Preterm neonates in resource-poor settings frequently develop hypothermia. Plastic bags or wraps are a low-cost intervention for the prevention of hypothermia in infants in developed countries.

For preterm infants born in a resource-poor health facility, placement in a plastic bag at birth can reduce the incidence of hypothermia at 1 hour after birth. (Read the full article)

Term neonates in resource-poor settings frequently develop hypothermia. Plastic bags or wraps are a low-cost intervention for the prevention of hypothermia in preterm and low birth weight infants that may also be effective in term infants.

For term neonates born in a resource-poor health facility, placement in a plastic bag at birth can reduce the incidence of hypothermia at 1 hour after birth. (Read the full article)

Persons with sickle cell anemia are known to have increased medical expenses, but little is known about the effects of hydroxyurea treatment on costs. In adults with severe sickle cell anemia, hydroxyurea has been reported to reduce expenses from hospitalization.

In this randomized placebo-controlled prospective multicenter trial of hydroxyurea in very young children with sickle cell anemia, not selected for severity, hydroxyurea was associated with significant medical cost savings due to a reduction in hospitalization expenses. (Read the full article)

Pneumonia is the leading cause of death in young children worldwide. Anemia, widely prevalent globally, is not routinely assessed when treating pneumonia. The effect of anemia and high altitude on outcome of pneumonia is not well described.

Anemia at high altitude increases the risk of poor outcome with severe pneumonia. Children with severe pneumonia at high altitude present with more severe hypoxemia and have a longer time to recovery than children at low altitude. (Read the full article)

Bacteremia occurs in 2.2% of febrile infants who have a blood culture drawn. Regional data suggest that Escherichia coli, group B Streptococcus, and Staphylococcus aureus are leading causes; however, the geographic boundaries of these data limit universal applicability.

This is the first national study examining epidemiology of bacteremia in febrile infants admitted to a general inpatient unit. The most common pathogens were Escherichia coli (42%), group B Streptococcus (23%), and Streptococcus pneumoniae (6%). No Listeria monocytogenes was identified. (Read the full article)

There is a perception that Gram-negative bacilli (GNB) bloodstream infection is increasing in the NICU, and those infections caused by a multidrug-resistant (MDR) strain are a growing threat to hospitalized patients.

Exposure to broad-spectrum antibiotics is the most important risk factor for MDR GNB bacteremia, which is associated with higher mortality. Neonates with risk factors for bacteremia caused by a MDR GNB strain may benefit from empirical antimicrobial therapy with carbapenem. (Read the full article)

Existing data do not demonstrate a need for combination therapy after antimicrobial susceptibility data indicate adequate in vitro activity with β-lactam monotherapy. However, the role of empirical combination therapy for the treatment of Gram-negative bacteremia in children remains unsettled.

We conducted a retrospective, propensity-score matched study demonstrating no improvement in 10-day mortality of children who have Gram-negative bacteremia receiving empirical β-lactam and aminoglycoside combination therapy compared with β-lactam monotherapy, unless the bacteremic episode was attributable to a multidrug-resistant organism. (Read the full article)

Hypothermia treatment of neonatal encephalopathy reduces death and disability from 66% to 50%; additional neuroprotective therapies are needed. We previously found in animal models that adding 50% xenon to the breathing gas during cooling doubled neuroprotection.

This clinical feasibility study used 50% xenon for 3 to 18 hours in 14 cooled infants with cardiovascular, respiratory, and amplitude-integrated EEG monitoring. This depressed seizures, with no blood pressure reduction. Xenon is ready for randomized clinical trials in newborns. (Read the full article)

Obstructive sleep apnea syndrome (OSAS) prevalence in children with sickle cell anemia is not well described. Although these children often experience nocturnal oxygen desaturation, it is unclear whether they are more likely to have OSAS.

Children with sickle cell anemia have a high prevalence of OSAS with typical symptoms, beyond just nocturnal oxyhemoglobin desaturation. This study supports the need for increased efforts to screen for, diagnose, and treat OSAS in this vulnerable population. (Read the full article)

For newborn infants, extreme hyperbilirubinemia (≥24.5 mg/dL) is associated with risk for severe bilirubin encephalopathy. The causal factor of extreme hyperbilirubinemia is often not established. The genotype of Gilbert syndrome, the UGT1A1*28 allele, is considered a potential risk factor.

The UGT1A1*28 allele was not associated with risk for developing extreme hyperbilirubinemia. (Read the full article)

Total serum bilirubin levels ≥30 mg/dL have been labeled as "hazardous." Levels this high are rare, occurring in 3 to 10 per 100 000 births. Few studies have examined etiologies and long-term outcomes in these infants.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a major identifiable cause, but is under-assessed. Chronic, bilirubin-induced neurotoxicity is rare and only occurred in the setting of additional risk factors (prematurity, G6PD deficiency, sepsis) and at levels far above recommended exchange transfusion thresholds. (Read the full article)

Hydroxyurea is a treatment option for young patients with sickle cell disease (SCD). Establishing the safety of hydroxyurea is of paramount importance. The effect of hydroxyurea on immune function and immunizations in SCD has not been studied previously.

Children with SCD receiving hydroxyurea have lower lymphocyte, CD4, and memory T-cell counts compared with those receiving placebo, but still in the range for healthy children. Despite slower response to measles vaccine, measles, mumps, and rubella and pneumococcal vaccines are effective. (Read the full article)

Direct antiglobulin titer (DAT) positive, blood group A or B newborns born to group O mothers have a high incidence of hyperbilirubinemia, attributable to increased hemolysis.

DAT ++ readings were associated with a higher incidence of hyperbilirubinemia and a greater degree of hemolysis than DAT ± or DAT + counterparts. DAT strength should be taken into consideration when planning treatment strategies or follow-up of ABO-heterospecific newborns. (Read the full article)

Childhood bacteremia caused by vaccine-preventable organisms has substantially declined over the last decade. Recognition of bacteremia in children is difficult, and delayed administration of antibiotics is associated with poor outcomes. Adults with health care–associated Gram-negative bacteremia experience delays in receiving appropriate antibiotics.

Bacteremia in children presenting to the emergency department is increasingly health care associated and resistant to empirical antibiotics. These infections are associated with increased length of stay. Rates of Gram-negative bacteremia have increased, and children with Gram-negative bacteremia experience delayed antibiotic administration. (Read the full article)

Guidelines for postdischarge monitoring of hyperbilirubinemia for neonates of white descent are available from the American Academy of Pediatrics; however, such information for healthy term and late preterm Chinese neonates is lacking.

A classification model for predicting the risk of significant hyperbilirubinemia in Chinese neonates was developed that combines a transcutaneous bilirubin–based nomogram with clinical risk factors. It classified newborns into 6 risk groups, which can guide clinicians in planning appropriate follow-up strategies. (Read the full article)

Objectives. The aim of this study was to assess the safety of early oral switch (EOS) prior to 14 days for low-risk Staphylococcus aureus bacteremia (LR-SAB), which is the primary treatment strategy employed at our institution. Usually recommended therapy is 14 days of intravenous (IV) antibiotics.

Methods. All patients with SAB at our hospital were identified between 1 January 2014 and 31 December 2018. Those meeting low-risk criteria (healthcare-associated, no evidence of deep infection or demonstrated involvement of prosthetic material, and no further positive blood cultures after 72-hours) were included in the study. The primary outcome was occurrence of a SAB-related complication within 90 days.

Results. There were 469 SAB episodes during the study period, 100 (21%) of whom met inclusion criteria. EOS was performed in 84 patients. In this group, line infection was the source in 79%, methicillin-susceptible S. aureus caused 95% of SABs and 74% of patients received IV flucloxacillin. The median duration of IV and oral antibiotics in the EOS group was 5 (IQR 4-6) and 10 days (IQR 9-14), respectively. Seventy-one percent of patients received flucloxacillin as their EOS agent. Overall, 86% of oral step-down therapy was with beta-lactams. One patient (1%) undergoing EOS had SAB relapse within 90 days. No deaths attributable to SAB occurred within 90 days.

Conclusions. In this low MRSA prevalence LR-SAB cohort, EOS was associated with a low incidence of SAB-related complications. This was achieved with oral beta-lactam therapy in most patients. Larger prospective studies are needed to confirm these findings.

Methicillin-resistant Staphylococcus aureus (MRSA) has grown to become a major burden on healthcare systems. The cumulation of limited therapeutic options and worsened patient outcomes with persistent MRSA bacteremia has driven research in optimizing its initial management. The guidelines published by the Infectious Disease of America currently recommend combination therapy for refractory MRSA bacteremia, but the utility of combining antibiotics from the start of therapy is under investigation. The alternative strategy of early use of a β-lactam antibiotics in combination with vancomycin upon initial MRSA bacteremia detection has shown promise. While this concept has gained international attention, providers should give this strategy serious consideration prior to implementation. The objective of this review is to examine retrospective and prospective evidence for early combination with vancomycin and β-lactam antibiotics, as well as explore potential consequences of combination therapy.

Background

Optimal concentrations of unbound antimicrobials are essential for maximum microbiological effect. Although hypoalbuminemia and albumin fluid resuscitation are common in critical care, the effects of different albumin concentrations on the unbound concentrations of highly protein-bound antimicrobials are not known. The aim of this study was to compare effects of different albumin states on total and unbound concentrations of ertapenem and ceftriaxone using an ovine model.

Methods

Design

Prospective, three phase intervention observational study.

Subjects

Healthy Merino sheep.

Interventions

Eight sheep were subject to three experimental phases; normoalbuminemia, hypoalbuminemia using plasmapheresis and albumin replacement using a 25% albumin solution. In each phase, ceftriaxone 40 mg/kg and ertapenem 15 mg/kg were given intravenously. Blood samples were collected at pre-defined intervals and analyzed using an ultra-high-performance liquid chromatography tandem mass spectrometry method. Pharmacokinetic parameters such as area under the curve (AUC_0-24), plasma clearance (CL) and apparent volume of distribution in the terminal phase (V_d) were estimated and compared between the phases.

Results

The protein and albumin concentrations were significantly different between phases. Hypoalbuminemia resulted in a significantly lower AUC_0-24 and higher CL of total and unbound concentrations of ceftriaxone compared to the other phases. Whereas albumin replacement led to higher AUC_0-24 and lower CL compared to other phases for both drugs. The V_d for total drug concentrations for both drugs were significantly lower with albumin replacement.

Conclusions

For highly protein-bound drugs such as ceftriaxone and ertapenem, both hypoalbuminemia and albumin replacement may affect unbound drug exposure.

Vinod K. Bhutani
Jan 1, 1999; 103:6-14
ARTICLES

As per reports, in India, every year 10,000 children are being born with thalassemia which approximately accounts for 10% of the total world incidence of thalassemia-affected children and one in eight of thalassemia carriers live in India.

There is only one cure for Thalassemia major at present, which is a bone marrow transplant with a suitable donor.

The injured student, identified as Shadab Farooq, is from Jammu & Kashmir, and a first-year student of mass communication at Jamia.

Let’s face it – the EDA industry needs new people and new ideas. One of the best places to find both is academia, and a presentation at the Cadence Theater at the recent Design Automation Conference (DAC 2015) described collaboration models that are working today.

The presentation was titled “Industry/Academia Engagement Models – From PhD Contests to R&D Collaborations.” It included these speakers, shown from left to right in the photo below:

• Prof. Xin Li, Electrical and Computer Engineering, Carnegie-Mellon University (CMU)
• Chuck Alpert, Senior Software Architect, Cadence
• Prof. Laleh Behjat, Department of Electrical and Computer Engineering, University of Calgary

Alpert, who was filling in for Zhuo Li, Software Architect at Cadence, was the vice chair of DAC 2015 and will be the general chair of DAC 2016 in Austin, Texas. “My team at Cadence really likes to collaborate with universities,” he said. “We’re a big proponent of education because we really need the best and brightest students in our industry.”

Contests Boost EDA Research

One way that Cadence collaborates with academia is participation in contests. “It’s a great way to formulate problems to academia,” Alpert said. “We can have the universities work on these problems and get some strategic direction.”

For example, Cadence has been involved with the annual CAD contest at the International Conference on Computer-Aided Design (ICCAD) since the contest was launched in 2012. This is the largest worldwide EDA R&D contest, and it is sponsored by the IEEE Council on EDA (CEDA) and the Taiwan Ministry of Education. Its goals are to boost EDA research in advanced real-world problems and to foster industry-academia collaboration.

Contestants can participate in one of more problems in the three areas of system design, logic synthesis and verification, and physical design. The 2015 contest has attracted 112 teams from 12 regions. Cadence contributes one problem per year in the logic synthesis area. Zhuo Li was the 2012 co-chair and the 2013 chair. The awards will be given at ICCAD in November 2015.

Another step that Cadence has taken, Alpert said, is to “hire lots of interns.” His own team has four interns at the moment. One advantage to interning at Cadence, he said, is that students get to see real-world designs and understand how the tools work. “It helps you drive your research in a more practical and useful direction,” he said.

The Cadence Academic Network co-sponsors the ACM SIGDA PhD Forum at DAC, and Xin Li and Zhuo Li are on the organizing committee. This event is a poster session for PhD students to present and discuss their dissertation research with people in the EDA community. This year’s forum was “packed,” Alpert said, and it’s clear that the event needs a bigger room.

Finally, Alpert noted, Cadence researchers write and publish technical papers at DAC and other conferences, and Cadence people serve on the DAC technical program committee. “We try to be involved with the academic community on a regular basis,” Alpert said. “We want the best and the brightest people to go into EDA because there is still so much innovation that’s needed. It’s a really cool place to be.”

Research Collaboration Exposes Failure Rates

Xin Li presented an example of a successful research collaboration between CMU and Cadence. The challenge was to find a better way to estimate potential failure rates in memory. As noted in a previous blog post, PhD student Shupeng Sun met this challenge with a new statistical methodology that won a Best Poster award at the ACM SIGDA PhD Forum at DAC 2014.

The new methodology is called Scaled-Sigma Sampling (SSS). It calculates the failure rate and accounts for variability in the manufacturing process while only requiring a few hundred, or a few thousand, sample circuit blocks. Previously, millions of samples were required for an accurate validation of a new design, and each sample could take minutes or hours to simulate. It could take a few weeks or months to run one validation.

The SSS methodology requires greatly reduced simulation times. It makes it possible, Li noted, to run simulations overnight and see the results in the morning.

Li shared his secret for success in collaborations. “I want to emphasize that before the collaboration, you have to understand the goal. If you don’t have a clear goal, don’t collaborate. Once you define the goal, stick to it and make it happen.”

Contest Provides Learning Experience

Last year Laleh Behjat handed two of her new PhD students a challenge. “I told them there is an ISPD [International Symposium for Physical Design] contest on placement, and I expect you to participate and I expect you to win. Not knowing anything about placement, I don’t think they realized what I was asking them.”

The 2015 contest was called the Blockage-Aware Detailed Routing-Driven Placement Contest. Results were announced at the end of March at ISPD. And the University of Calgary team, despite its lack of placement experience, took second place.

Such contests provide a good learning tool, according to Behjat. Graduate students in EDA, she said, “have to be good programmers. They have to work in teams and be collaborative, be able to innovate, and solve the hardest problems I have seen in engineering and science. And they have to think outside the box.” A contest can bring out all these attributes, she said.

Further, Behjat noted, contest participants had access to benchmarks and to a placement tool. They didn’t have to write tools to find out if their results were good. Industry sponsors, meanwhile, got access to good students and new approaches for solving problems.

“You can see Cadence putting a big amount of time, effort and money to get students here and get them excited about doing contests,” she said. She advised students in the theater audience to “talk to people in the Cadence booth and see if you can have more ideas for collaboration.”

Richard Goering

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Indian actor Rishi Kapoor, who starred in celebrated Bollywood movies such as "Bobby" and "Mera Naam Joker", died on Thursday after a two-year battle with leukemia, his family said.

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Diamond-Blackfan anemia: A genetic condition affecting the bone marrow that leads to anemia (low numbers of red blood cells) and often, birth defects. It affects five to 10 out of every million babies born in the U.S. A number of genetic mutations have been identified that can cause Diamond-Blackfan anemia, and it is inherited in an autosomal dominant pattern, meaning that only one copy of the defective gene is needed to cause the disorder. In about 45% of cases, those affected inherit a defective gene from one parent. In the remaining cases, a new mutation (change in the gene) occurs in people who do not have the condition in their family.

Symptoms and signs of Diamond-Blackfan anemia usually are seen during the first year of life and relate to the anemia and shortage of oxygen delivery to tissues from the low numbers of red blood cells. These symptoms include pallor, fatigue, and weakness. People with this disorder are at increased risk for developing myelodysplastic syndrome, another bone marrow disorder, acute myeloid leukemia (AML), and a type of bone cancer known as osteosarcoma. The birth defects that can accompany the bone marrow disorders are seen in about half of those affected and can vary in severity. Associated birth defects can include small head size (microcephaly); wide-set eyes (hypertelorism); droopy eyelids (ptosis); a low frontal hairline; a broad, flat bridge of the nose; small, low-set ears; and small lower jaw (micrognathia). Cleft palate and/or cleft lip may also be present. Slow growth, eye problems, and kidney problems are sometimes associated with the condition. Red blood cell transfusions and corticosteroid medications are the main treatments for Diamond-Blackfan anemia. Stem cell transplants have been performed successfully in some children with the condition.

ABSTRACT

Many HIV prevention strategies are currently under consideration where it is highly informative to know the study participants’ times of infection. These can be estimated using viral sequence data sampled early in infection. However, there are several scenarios that, if not addressed, can skew timing estimates. These include multiple transmitted/founder (TF) viruses, APOBEC (apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like)-mediated mutational enrichment, and recombination. Here, we suggest a pipeline to identify these problems and resolve the biases that they introduce. We then compare two modeling strategies to obtain timing estimates from sequence data. The first, Poisson Fitter (PF), is based on a Poisson model of random accumulation of mutations relative to the TF virus (or viruses) that established the infection. The second uses a coalescence-based phylogenetic strategy as implemented in BEAST. The comparison is based on timing predictions using plasma viral RNA (cDNA) sequence data from 28 simian-human immunodeficiency virus (SHIV)-infected animals for which the exact day of infection is known. In this particular setting, based on nucleotide sequences from samples obtained in early infection, the Poisson method yielded more accurate, more precise, and unbiased estimates for the time of infection than did the explored implementations of BEAST.

IMPORTANCE The inference of the time of infection is a critical parameter in testing the efficacy of clinical interventions in protecting against HIV-1 infection. For example, in clinical trials evaluating the efficacy of passively delivered antibodies (Abs) for preventing infections, accurate time of infection data are essential for discerning levels of the Abs required to confer protection, given the natural Ab decay rate in the human body. In such trials, genetic sequences from early in the infection are regularly sampled from study participants, generally prior to immune selection, when the viral population is still expanding and genetic diversity is low. In this particular setting of early viral growth, the Poisson method is superior to the alternative approach based on coalescent methods. This approach can also be applied in human vaccine trials, where accurate estimates of infection times help ascertain if vaccine-elicited immune protection wanes over time.

ABSTRACT

Simian immunodeficiency virus (SIV)-infected nonhuman primates can serve as a relevant model for AIDS neuropathogenesis. Current SIV-induced encephalitis (SIVE)/neurological complications of AIDS (neuroAIDS) models are generally associated with rapid progression to neuroAIDS, which does not reflect the tempo of neuroAIDS progression in humans. Recently, we isolated a neuropathogenic clone, SIVsm804E-CL757 (CL757), obtained from an SIV-infected rhesus macaque (RM). CL757 causes a more protracted progression to disease, inducing SIVE in 50% of inoculated animals, with high cerebral spinal fluid viral loads, multinucleated giant cells (MNGCs), and perivascular lymphocytic cuffing in the central nervous system (CNS). This latter finding is reminiscent of human immunodeficiency virus (HIV) encephalitis in humans but not generally observed in rapid progressor animals with neuroAIDS. Here, we studied which subsets of cells within the CNS were targeted by CL757 in animals with neurological symptoms of SIVE. Immunohistochemistry of brain sections demonstrated infiltration of CD4⁺ T cells (CD4) and macrophages (Ms) to the site of MNGCs. Moreover, an increase in mononuclear cells isolated from the brain tissues of RMs with SIVE correlated with increased cerebrospinal fluid (CSF) viral load. Subset analysis showed a specific increase in brain CD4⁺ memory T cells (Br-mCD4), brain-Ms (Br-Ms), and brain B cells (Br-B cells). Both Br-mCD4s and Br-Ms harbored replication-competent viral DNA, as demonstrated by virus isolation by coculture. However, only in animals exhibiting SIVE/neuroAIDS was virus isolated from Br-Ms. These findings support the use of CL757 to study the pathogenesis of AIDS viruses in the central nervous system and indicate a previously unanticipated role of CD4s cells as a potential reservoir in the brain.

IMPORTANCE While the use of combination antiretroviral therapy effectively suppresses systemic viral replication in the body, neurocognitive disorders as a result of HIV infection of the central nervous system (CNS) remain a clinical problem. Therefore, the use of nonhuman primate models is necessary to study mechanisms of neuropathogenesis. The neurotropic, molecular clone SIVsm804E-CL757 (CL757) results in neuroAIDS in 50% of infected rhesus macaques approximately 1 year postinfection. Using CL757-infected macaques, we investigate disease progression by examining subsets of cells within the CNS that were targeted by CL757 and could potentially serve as viral reservoirs. By isolating mononuclear cells from the brains of SIV-infected rhesus macaques with and without encephalitis, we show that immune cells invade the neuroparenchyma and increase in number in the CNS in animals with SIV-induced encephalitis (SIVE). Of these cells, both brain macrophages and brain memory CD4⁺ T cells harbor replication-competent SIV DNA; however, only brain CD4⁺ T cells harbored SIV DNA in animals without SIVE. These findings support use of CL757 as an important model to investigate disease progression in the CNS and as a model to study virus reservoirs in the CNS.

Simian-human immunodeficiency virus (SHIV) infection of rhesus monkeys is an important preclinical model for human immunodeficiency virus type 1 (HIV-1) vaccines, therapeutics, and cure strategies. SHIVs have been optimized by incorporating HIV-1 Env residue 375 mutations that mimic the bulky or hydrophobic residues typically found in simian immunodeficiency virus (SIV) Env to improve rhesus CD4 binding. We applied this strategy to three SHIV challenge stocks (SHIV-SF162p3, SHIV-AE16, and SHIV-325c) and observed three distinct outcomes. We constructed six Env375 variants (M, H, W, Y, F, and S) for each SHIV, and we performed a pool competition study in rhesus monkeys to define the optimal variant for each SHIV prior to generating large-scale challenge stocks. We identified SHIV-SF162p3S/wild type, SHIV-AE16W, and SHIV-325cH as the optimal variants. SHIV-SF162p3S could not be improved, as it already contained the optimal Env375 residue. SHIV-AE16W exhibited a similar replicative capacity to the parental SHIV-AE16 stock. In contrast, SHIV-325cH demonstrated a 2.6-log higher peak and 1.6-log higher setpoint viral loads than the parental SHIV-325c stock. These data demonstrate the diversity of potential outcomes following Env375 modification in SHIVs. Moreover, the clade C SHIV-325cH challenge stock may prove useful for evaluating prophylactic or therapeutic interventions against clade C HIV-1.

IMPORTANCE We sought to enhance the infectivity of three SHIV stocks by optimization of a key residue in human immunodeficiency virus type 1 (HIV-1) Env (Env375). We developed the following three new simian-human immunodeficiency virus (SHIV) stocks: SHIV-SF162p3S/wild type, SHIV-AE16W, and SHIV-325cH. SHIV-SF162p3S could not be optimized, SHIV-AE16W proved comparable to the parental virus, and SHIV-325cH demonstrated markedly enhanced replicative capacity compared with the parental virus.

HIV-1 persists in cellular reservoirs that can reignite viremia if antiretroviral therapy (ART) is interrupted. Therefore, insight into the nature of those reservoirs may be revealed from the composition of recrudescing viremia following treatment cessation. A minor population of macrophage-tropic (M-tropic) viruses was identified in a library of recombinant viruses...

Multidrug resistance (MDR) in cancer arises from cross-resistance to structurally- and functionally-divergent chemotherapeutic drugs. In particular, MDR is characterized by increased expression and activity of ATP-binding cassette (ABC) superfamily transporters. Sphingolipids are substrates of ABC proteins in cell signaling, membrane biosynthesis, and inflammation, for example, and their products can favor cancer progression. Glucosylceramide (GlcCer) is a ubiquitous glycosphingolipid (GSL) generated by glucosylceramide synthase, a key regulatory enzyme encoded by the UDP-glucose ceramide glucosyltransferase (UGCG) gene. Stressed cells increase de novo biosynthesis of ceramides, which return to sub-toxic levels after UGCG mediates incorporation into GlcCer. Given that cancer cells seem to mobilize UGCG and have increased GSL content for ceramide clearance, which ultimately contributes to chemotherapy failure, here we investigated how inhibition of GSL biosynthesis affects the MDR phenotype of chronic myeloid leukemias. We found that MDR is associated with higher UGCG expression and with a complex GSL profile. UGCG inhibition with the ceramide analog d-threo-1-(3,4,-ethylenedioxy)phenyl-2-palmitoylamino-3-pyrrolidino-1-propanol (EtDO-P4) greatly reduced GSL and monosialotetrahexosylganglioside levels, and co-treatment with standard chemotherapeutics sensitized cells to mitochondrial membrane potential loss and apoptosis. ABC subfamily B member 1 (ABCB1) expression was reduced, and ABCC-mediated efflux activity was modulated by competition with nonglycosylated ceramides. Consistently, inhibition of ABCC-mediated transport reduced the efflux of exogenous C6-ceramide. Overall, UGCG inhibition impaired the malignant glycophenotype of MDR leukemias, which typically overcomes drug resistance through distinct mechanisms. This work sheds light on the involvement of GSL in chemotherapy failure, and its findings suggest that targeted GSL modulation could help manage MDR leukemias.

Premature infants have a higher incidence of indirect hyperbilirubinemia than term infants. Management of neonatal indirect hyperbilirubinemia in late preterm and term neonates has been well addressed by recognized, consensus-based guidelines. However, the extension of these guidelines to the preterm population has been an area of uncertainty because of limited evidence. This leads to variation in clinical practice and lack of recognition of the spectrum of bilirubin-induced neurologic dysfunction (BIND) in this population. Preterm infants are metabolically immature and at higher risk for BIND at lower bilirubin levels than their term counterparts. Early use of phototherapy to eliminate BIND and minimize the need for exchange transfusion is the goal of treatment in premature neonates. Although considered relatively safe, phototherapy does have side effects, and some NICUs tend to overuse phototherapy. In this review, we describe the epidemiology and pathophysiology of BIND in preterm neonates, and discuss our approach to standardized management of indirect hyperbilirubinemia in the vulnerable preterm population. The proposed treatment charts suggest early use of phototherapy in preterm neonates with the aim of reducing exposure to high irradiance levels, minimizing the need for exchange transfusions, and preventing BIND. The charts are pragmatic and have additional curves for stopping phototherapy and escalating its intensity. Having a standardized approach would support future research and quality improvement initiatives that examine dose and duration of phototherapy exposure with relation to outcomes.

Pre-eclampsia (PE)-induced fetal programming predisposes offspring to health hazards in adult life. Here, we tested the hypothesis that pre-eclamptic fetal programming elicits sexually dimorphic inflammatory and cardiovascular complications to endotoxemia in adult rat offspring. PE was induced by oral administration of L-NAME (50 mg/kg per day for seven consecutive days) starting from day 14 of conception. Cardiovascular studies were performed in conscious adult male and female offspring preinstrumented with femoral indwelling catheters. Compared with non-PE male counterparts, intravenous administration of lipopolysaccharide (LPS, 5 mg/kg) to PE male offspring caused significantly greater 1) falls in blood pressure, 2) increases in heart rate, 3) rises in arterial dP/dtmax, a correlate of left ventricular contractility, and 4) decreases in time- and frequency-domain indices of heart rate variability (HRV). By contrast, the hypotensive and tachycardic actions of LPS in female offspring were independent of the pre-eclamptic state and no clear changes in HRV or dP/dtmax were noted. Measurement of arterial baroreflex activity by vasoactive method revealed no sex specificity in baroreflex dysfunction induced by LPS. Immunohistochemical studies showed increased protein expression of toll-like receptor 4 in heart as well as in brainstem neuronal pools of the nucleus of solitary tract and rostral ventrolateral medulla in endotoxic PE male, but not female, offspring. Enhanced myocardial, but not neuronal, expression of monocyte chemoattractant protein-1 was also demonstrated in LPS-treated male offspring. Together, pre-eclamptic fetal programming aggravates endotoxic manifestations of hypotension and autonomic dysfunction in male offspring via exacerbating myocardial and neuromedullary inflammatory pathways.

An aberrant bi-apical Follicucullus specimen (Albaillellaria, Radiolaria) has been discovered from an upper Guadalupian (Middle Permian) chert block of the Kamiaso Unit of the Mino terrane, central Japan. If this specimen was formed with double malformation, it would be the oldest record of this phenomenon in radiolarians and the first record of its kind in Albaillellaria.

An exceptionally well-preserved specimen of the articulated rhodophyte Permocalculus, compared with P. tenellus sensu Elliott, 1955, is described from fine-grained Upper Permian limestones of the Khuff Formation of Saudi Arabia. Longitudinal medullary and sheaf-like cortical filaments extend through the uniserial series of elongate-globular, concave- and convex-terminating, interlocking segments for which they are interpreted to have functioned in articulation. The filaments tend to splay and branch laterally into the cortex where they terminate at the pores. At the terminal aperture, the filaments extend as bifurcating and possibly trifurcating branches and may serve as the origin of a new segment. Numerous elongate-globular chambers, up to five in each row and intimately involved with the filaments, are developed in the outer medulla and are considered to represent reproductive sporangia. The specimen is considered to have occupied predominantly low-energy, normal to slightly elevated salinity, shallow conditions within the subtidal regime of a lagoon.

OBJECTIVE

Debate continues regarding the influence of dietary fats and sugars on the risk of developing metabolic diseases, including insulin resistance and nonalcoholic fatty liver disease (NAFLD). We investigated the effect of two eucaloric diets, one enriched with saturated fat (SFA) and the other enriched with free sugars (SUGAR), on intrahepatic triacylglycerol (IHTAG) content, hepatic de novo lipogenesis (DNL), and whole-body postprandial metabolism in overweight males.

OBJECTIVE

We evaluated the effect of optimizing metformin dosing on glycemia and body weight in type 2 diabetes.

To identify genomic alterations contributing to the pathogenesis of high-risk chronic lymphocytic leukemia (CLL) beyond the well-established role of TP53 aberrations, we comprehensively analyzed 75 relapsed/refractory and 71 treatment-naïve high-risk cases from prospective clinical trials by single nucleotide polymorphism arrays and targeted next-generation sequencing. Increased genomic complexity was a hallmark of relapsed/refractory and treatment-naïve high-risk CLL. In relapsed/refractory cases previously exposed to the selective pressure of chemo(immuno)therapy, gain(8)(q24.21) and del(9)(p21.3) were particularly enriched. Both alterations affect key regulators of cell-cycle progression, namely MYC and CDKN2A/B. While homozygous CDKN2A/B loss has been directly associated with Richter transformation, we did not find this association for heterozygous loss of CDKN2A/B. Gains in 8q24.21 were either focal gains in a MYC enhancer region or large gains affecting the MYC locus, but only the latter type was highly enriched in relapsed/refractory CLL (17%). In addition to a high frequency of NOTCH1 mutations (23%), we found recurrent genetic alterations in SPEN (4% mutated), RBPJ (8% deleted) and SNW1 (8% deleted), all affecting a protein complex that represses transcription of NOTCH1 target genes. We investigated the functional impact of these alterations on HES1, DTX1 and MYC gene transcription and found derepression of these NOTCH1 target genes particularly with SPEN mutations. In summary, we provide new insights into the genomic architecture of high-risk CLL, define novel recurrent DNA copy number alterations and refine knowledge on del(9p), gain(8q) and alterations affecting NOTCH1 signaling. This study was registered at ClinicalTrials.gov with number NCT01392079.

Tlarge granular lymphocyte leukemia (T-LGLL) is characterized by the expansion of several large granular lymphocyte clones, among which a subset of large granular lymphocytes showing constitutively activated STAT3, a specific CD8⁺/CD4^– phenotype and the presence of neutropenia has been identified. Although STAT3 is an inducer of transcription of a large number of oncogenes, so far its relationship with miRNAs has not been evaluated in T-LGLL patients. Here, we investigated whether STAT3 could carry out its pathogenetic role in T-LGLL through an altered expression of miRNAs. The expression level of 756 mature miRNA was assessed on purified T large granular lymphocytes (T-LGLs) by using a TaqMan Human microRNA Array. Hierarchical Clustering Analysis of miRNA array data shows that the global miRNome clusters with CD8 T-LGLs. Remarkably, CD8 T-LGLs exhibit a selective and STAT3-dependent repression of miR-146b expression, that significantly correlated with the absolute neutrophil counts and inversely correlated with the expression of Fas ligand (FasL), that is regarded as the most relevant factor in the pathogenesis of neutropenia. Experimental evidence demonstrates that the STAT3-dependent reduction of miR-146b expression in CD8 T-LGLs occurs as a consequence of miR-146b promoter hypermethylation and results in the disruption of the HuR-mediated post-transcriptional machinery controlling FasL mRNA stabilization. Restoring miR-146b expression in CD8 T-LGLs lead to a reduction of HuR protein and, in turn, of FasL mRNA expression, thus providing mechanistic insights for the existence of a STAT3-miR146b-FasL axis and neutropenia in T-LGLL.

Megakaryoblastic leukemia 1 (MKL1) is a coactivator of serum response factor and together they regulate transcription of actin cytoskeleton genes. MKL1 is associated with hematologic malignancies and immunodeficiency, but its role in B cells is unexplored. Here we examined B cells from monozygotic triplets with an intronic deletion in MKL1, two of whom had been previously treated for Hodgkin lymphoma (HL). To investigate MKL1 and B-cell responses in the pathogenesis of HL, we generated Epstein-Barr virus-transformed lymphoblastoid cell lines from the triplets and two controls. While cells from the patients with treated HL had a phenotype close to that of the healthy controls, cells from the undiagnosed triplet had increased MKL1 mRNA, increased MKL1 protein, and elevated expression of MKL1-dependent genes. This profile was associated with elevated actin content, increased cell spreading, decreased expression of CD11a integrin molecules, and delayed aggregation. Moreover, cells from the undiagnosed triplet proliferated faster, displayed a higher proportion of cells with hyperploidy, and formed large tumors in vivo. This phenotype was reversible by inhibiting MKL1 activity. Interestingly, cells from the triplet treated for HL in 1985 contained two subpopulations: one with high expression of CD11a that behaved like control cells and the other with low expression of CD11a that formed large tumors in vivo similar to cells from the undiagnosed triplet. This implies that pre-malignant cells had re-emerged a long time after treatment. Together, these data suggest that dysregulated MKL1 activity participates in B-cell transformation and the pathogenesis of HL.

Cytogenetic risk stratification at diagnosis has long been one of the most useful tools to assess prognosis in acute lymphoblastic leukemia (ALL). To examine the prognostic impact of cytogenetic abnormalities on outcomes after allogeneic hematopoietic cell transplantation, we studied 1731 adults with Philadelphia-negative ALL in complete remission who underwent myeloablative or reduced intensity/non-myeloablative conditioning transplant from unrelated or matched sibling donors reported to the Center for International Blood and Marrow Transplant Research. A total of 632 patients had abnormal conventional metaphase cytogenetics. The leukemia-free survival and overall survival rates at 5 years after transplantation in patients with abnormal cytogenetics were 40% and 42%, respectively, which were similar to those in patients with a normal karyotype. Of the previously established cytogenetic risk classifications, modified Medical Research Council-Eastern Cooperative Oncology Group score was the only independent prognosticator of leukemia-free survival (P=0.03). In the multivariable analysis, monosomy 7 predicted post-transplant relapse [hazard ratio (HR)=2.11; 95% confidence interval (95% CI): 1.04-4.27] and treatment failure (HR=1.97; 95% CI: 1.20-3.24). Complex karyotype was prognostic for relapse (HR=1.69; 95% CI: 1.06-2.69), whereas t(8;14) predicted treatment failure (HR=2.85; 95% CI: 1.35-6.02) and overall mortality (HR=3.03; 95% CI: 1.44-6.41). This large study suggested a novel transplant-specific cytogenetic scheme with adverse [monosomy 7, complex karyotype, del(7q), t(8;14), t(11;19), del(11q), tetraploidy/near triploidy], intermediate (normal karyotype and all other abnormalities), and favorable (high hyperdiploidy) risks to prognosticate leukemia-free survival (P=0.02). Although some previously established high-risk Philadelphia-negative cytogenetic abnormalities in ALL can be overcome by transplantation, monosomy 7, complex karyotype, and t(8;14) continue to pose significant risks and yield inferior outcomes.

Despite substantial progress in treatment of T-cell acute lymphoblastic leukemia (T-ALL), mortality remains relatively high, mainly due to primary or acquired resistance to chemotherapy. Further improvements in survival demand better understanding of T-ALL biology and development of new therapeutic strategies. The Notch pathway has been involved in the pathogenesis of this disease and various therapeutic strategies are currently under development, including selective targeting of NOTCH receptors by inhibitory antibodies. We previously demonstrated that the NOTCH1-specific neutralizing antibody OMP52M51 prolongs survival in TALL patient-derived xenografts bearing NOTCH1/FBW7 mutations. However, acquired resistance to OMP52M51 eventually developed and we used patient-derived xenografts models to investigate this phenomenon. Multi-level molecular characterization of T-ALL cells resistant to NOTCH1 blockade and serial transplantation experiments uncovered heterogeneous types of resistance, not previously reported with other Notch inhibitors. In one model, resistance appeared after 156 days of treatment, it was stable and associated with loss of Notch inhibition, reduced mutational load and acquired NOTCH1 mutations potentially affecting the stability of the heterodimerization domain. Conversely, in another model resistance developed after only 43 days of treatment despite persistent down-regulation of Notch signaling and it was accompanied by modulation of lipid metabolism and reduced surface expression of NOTCH1. Our findings shed light on heterogeneous mechanisms adopted by the tumor to evade NOTCH1 blockade and support clinical implementation of antibody-based target therapy for Notch-addicted tumors.

Immunotherapeutic strategies targeting the rare leukemic stem cell compartment might provide salvage to the high relapse rates currently observed in acute myeloid leukemia (AML). We applied gene expression profiling for comparison of leukemic blasts and leukemic stem cells with their normal counterparts. Here, we show that the T-cell receptor chain alternate reading frame protein (TARP) is over-expressed in de novo pediatric (n=13) and adult (n=17) AML sorted leukemic stem cells and blasts compared to hematopoietic stem cells and normal myeloblasts (15 healthy controls). Moreover, TARP expression was significantly associated with a fms-like tyrosine kinase receptor-3 internal tandem duplication in pediatric AML. TARP overexpression was confirmed in AML cell lines (n=9), and was found to be absent in B-cell acute lymphocytic leukemia (n=5) and chronic myeloid leukemia (n=1). Sequencing revealed that both a classical TARP transcript, as described in breast and prostate adenocarcinoma, and an AML-specific alternative TARP transcript, were present. Protein expression levels mostly matched transcript levels. TARP was shown to reside in the cytoplasmic compartment and showed sporadic endoplasmic reticulum co-localization. TARP-T-cell receptor engineered cytotoxic T-cells in vitro killed AML cell lines and patient leukemic cells co-expressing TARP and HLA-A*0201. In conclusion, TARP qualifies as a relevant target for immunotherapeutic T-cell therapy in AML.