Analyzing global steroid metabolism in humans can shed light on the etiologies of steroid-related diseases. However, existing methods require large amounts of serum and lack the evaluation of accuracy. Here, we developed an LC/MS/MS method for the simultaneous quantification of 12 steroid hormones: testosterone, pregnenolone, progesterone, androstenedione, corticosterone, 11-deoxycortisol, cortisol, 17-hydroxypregnenolone, 17-hydroxyprogesterone, dehydroepiandrosterone, estriol, and estradiol. Steroids and spiked internal standards in 100 μl serum were extracted by protein precipitation and liquid-liquid extraction. The organic phase was dried by evaporation, and isonicotinoyl chloride was added for steroid derivatization, followed by evaporation under nitrogen and redissolution in 50% methanol. Chromatographic separation was performed on a reverse-phase PFP column, and analytes were detected on a triple quadrupole mass spectrometer with ESI. The lower limits of quantification ranged from 0.005 ng/ml for estradiol to 1 ng/ml for cortisol. Apparent recoveries of steroids at high, medium, and low concentrations in quality control samples were between 86.4% and 115.0%. There were limited biases (–10.7% to 10.5%) between the measured values and the authentic values, indicating that the method has excellent reliability. An analysis of the steroid metabolome in pregnant women highlighted the applicability of the method in clinical serum samples. We conclude that the LC/MS/MS method reported here enables steroid metabolome analysis with high accuracy and reduced serum consumption, indicating that it may be a useful tool in both clinical and scientific laboratory research.

Steroids that contain a 3-hydroxyl group (3-OH steroids) are widely distributed in nature. During analysis with ESI-MS, they easily become dehydrated while in the protonated form, resulting in the production of several precursor ions and leading to low sensitivity of detection. To address this analytical challenge, here, we developed a method for the quantitation of 3-OH steroids by LC-MS/MS coupled with post-column addition of lithium (Li) ions to the mobile phase. The Li ion has a high affinity for the keto group of steroids, stabilizing their structures during ionization and permitting detection of analytes exclusively as the lithiated form. This not only improved the intensities of the precursor ions, but also promoted the formation of typical lithiated fragment ions. This improvement made the quantitation by multiple reaction monitoring more sensitive and reliable, as evidenced by 1.53–188 times enhanced detection sensitivity of 13 steroids that contained at least one keto and two hydroxyl groups or one keto and one 5-olefinic double bond, among 16 different 3-OH steroids. We deployed our newly developed method for profiling steroids in mouse brain tissue and identified six steroids in one tissue sample. Among these, 16-hydroxyestrone, tetrahydrocorticosterone, and 17α-hydroxypregnenolone were detected for the first time in the mouse brain. In summary, the method described here enables the detection of lithiated steroids by LC-MS/MS, including three 3-OH steroids not previously reported in the mouse brain. We anticipate that this new method may allow the determination of 3-OH steroids in different brain regions.

Alcoholic liver disease (ALD) is the most prevalent type of chronic liver disease with significant morbidity and mortality worldwide. ALD begins with simple hepatic steatosis and progresses to alcoholic steatohepatitis, fibrosis, and cirrhosis. The severity of hepatic steatosis is highly associated with the development of later stages of ALD. This review explores the disturbances of alcohol-induced hepatic lipid metabolism through altered hepatic lipid uptake, de novo lipid synthesis, fatty acid oxidation, hepatic lipid export, and lipid droplet formation and catabolism. In addition, we review emerging data on the contributions of genetics and bioactive lipid metabolism in alcohol-induced hepatic lipid accumulation.

Adipocytes take up long chain FAs through diffusion and protein-mediated transport, whereas FA efflux is considered to occur by diffusion. To identify potential membrane proteins that are involved in regulating FA flux in adipocytes, the expression levels of 55 membrane transporters without known function were screened in subcutaneous adipose samples from obese patients before and after bariatric surgery using branched DNA methodology. Among the 33 solute carrier (SLC) transporter family members screened, the expression of 14 members showed significant changes before and after bariatric surgery. One of them, Slc43a3, increased about 2.5-fold after bariatric surgery. Further investigation demonstrated that Slc43a3 is highly expressed in murine adipose tissue and induced during adipocyte differentiation in primary preadipocytes and in OP9 cells. Knockdown of Slc43a3 with siRNA in differentiated OP9 adipocytes reduced both basal and forskolin-stimulated FA efflux, while also increasing FA uptake and lipid droplet accumulation. In contrast, overexpression of Slc43a3 decreased FA uptake in differentiated OP9 cells and resulted in decreased lipid droplet accumulation. Therefore, Slc43a3 seems to regulate FA flux in adipocytes, functioning as a positive regulator of FA efflux and as a negative regulator of FA uptake.

Treatment of patients with chronic lymphocytic leukemia (CLL) with inhibitors of Bruton's tyrosine kinase (BTK), such as ibrutinib, is limited by primary or secondary resistance to this drug. Examinations of CLL patients with late relapses while on ibrutinib, which inhibits BTK's catalytic activity, revealed several mutations in BTK, most frequently resulting in the C481S substitution, and disclosed many mutations in PLCG2, encoding phospholipase C-γ2 (PLCγ2). The PLCγ2 variants typically do not exhibit constitutive activity in cell-free systems, leading to the suggestion that in intact cells they are hypersensitive to Rac family small GTPases or to the upstream kinases spleen-associated tyrosine kinase (SYK) and Lck/Yes-related novel tyrosine kinase (LYN). The sensitivity of the PLCγ2 variants to BTK itself has remained unknown. Here, using genetically-modified DT40 B lymphocytes, along with various biochemical assays, including analysis of PLCγ2-mediated inositol phosphate formation, inositol phospholipid assessments, fluorescence recovery after photobleaching (FRAP) static laser microscopy, and determination of intracellular calcium ([Ca2+]i), we show that various CLL-specific PLCγ2 variants such as PLCγ2S707Y are hyper-responsive to activated BTK, even in the absence of BTK's catalytic activity and independently of enhanced PLCγ2 phospholipid substrate supply. At high levels of B-cell receptor (BCR) activation, which may occur in individual CLL patients, catalytically-inactive BTK restored the ability of the BCR to mediate increases in [Ca2+]i. Because catalytically-inactive BTK is insensitive to active-site BTK inhibitors, the mechanism involving the noncatalytic BTK uncovered here may contribute to preexisting reduced sensitivity or even primary resistance of CLL to these drugs.

Nonalcoholic fatty liver disease (NAFLD) is a risk factor for type 2 diabetes (T2D). We aimed to identify the peripheral blood DNA methylation signature of hepatic fat. We conducted epigenome-wide association studies of hepatic fat in 3,400 European ancestry (EA) participants and in 401 Hispanic ancestry and 724 African ancestry participants from four population-based cohort studies. Hepatic fat was measured using computed tomography or ultrasound imaging and DNA methylation was assessed at >400,000 cytosine-guanine dinucleotides (CpGs) in whole blood or CD14+ monocytes using a commercial array. We identified 22 CpGs associated with hepatic fat in EA participants at a false discovery rate <0.05 (corresponding P = 6.9 x 10^–6) with replication at Bonferroni-corrected P < 8.6 x 10^–4. Mendelian randomization analyses supported the association of hypomethylation of cg08309687 (LINC00649) with NAFLD (P = 2.5 x 10^–4). Hypomethylation of the same CpG was also associated with risk for new-onset T2D (P = 0.005). Our study demonstrates that a peripheral blood–derived DNA methylation signature is robustly associated with hepatic fat accumulation. The hepatic fat–associated CpGs may represent attractive biomarkers for T2D. Future studies are warranted to explore mechanisms and to examine DNA methylation signatures of NAFLD across racial/ethnic groups.

Amylin, a pancreatic hormone and neuropeptide, acts principally in the hindbrain to decrease food intake and has been recently shown to act as a neurotrophic factor to control the development of AP->NTS and ARC->PVN axonal fiber outgrowth. Amylin is also able to activate ERK signaling specifically in POMC neurons independently of leptin. To investigate the physiological role of amylin signaling in POMC neurons, the core component of the amylin receptor, calcitonin receptor (CTR) was depleted from POMC neurons using an inducible mouse model. The loss of CTR in POMC neurons leads to increased body weight gain, increased adiposity, and glucose intolerance in male knockout mice, characterized by decreased energy expenditure (EE) and decreased expression of uncoupling protein 1 (UCP1) in brown adipose tissue (BAT). Furthermore, a decreased spontaneous locomotor activity and absent thermogenic reaction to the application of the amylin receptor agonist were observed in male and female mice. Together, these results show a significant physiological impact of amylin/calcitonin signaling in CTR-POMC neurons on energy metabolism and demonstrate the need for sex-specific approaches in obesity research and potentially treatment.

Nonalcoholic steatohepatitis has emerged as a major cause of liver diseases with no effective therapies. Here, we evaluate the efficacies and pharmacokinetics of B1344, a long-acting PEGylated FGF21 analog, in a nongenetically modified nonhuman primate species that underwent liver biopsy, and demonstrate the potential for efficacies in humans. B1344 is sufficient to selectively activate signaling from the βKlotho/FGFR1c receptor complex. In cynomolgus monkeys with nonalcoholic fatty liver disease, administration of B1344 via subcutaneous injection for eleven weeks caused a profound reduction of hepatic steatosis, inflammation and fibrosis, and amelioration of liver injury and hepatocyte death as evidenced by liver biopsy and biochemical analysis. Moreover, improvement of metabolic parameters was observed in the monkey, including reduction of body weight and improvement of lipid profiles and glycemic control. To determine the role of B1344 in the progression of murine NAFLD independent of obesity, administration of B1344 were performed in mice fed with methionine and choline deficiency diet. Consistently, B1344 administration prevented the mice from lipotoxicity damage and nonalcoholic steatohepatitis at a dose-dependent manner. These results provide preclinical validation for an innovative therapeutics to NAFLD, and support further clinical testing of B1344 for treating nonalcoholic steatohepatitis and other metabolic diseases in humans.

Barttin is the accessory subunit of the human ClC-K chloride channels, which are expressed in both the kidney and inner ear. Barttin promotes trafficking of the complex it forms with ClC-K to the plasma membrane and is involved in activating this channel. Barttin undergoes post-translational palmitoylation that is essential for its functions, but the enzyme(s) catalyzing this post-translational modification is unknown. Here, we identified zinc finger DHHC-type containing 7 (DHHC7) protein as an important barttin palmitoyl acyltransferase, whose depletion affected barttin palmitoylation and ClC-K-barttin channel activation. We investigated the functional role of barttin palmitoylation in vivo in Zdhhc7−/− mice. Although palmitoylation of barttin in kidneys of Zdhhc7−/− animals was significantly decreased, it did not pathologically alter kidney structure and functions under physiological conditions. However, when Zdhhc7−/− mice were fed a low-salt diet, they developed hyponatremia and mild metabolic alkalosis, symptoms characteristic of human Bartter syndrome (BS) type IV. Of note, we also observed decreased palmitoylation of the disease-causing R8L barttin variant associated with human BS type IV. Our results indicate that dysregulated DHHC7-mediated barttin palmitoylation appears to play an important role in chloride channel dysfunction in certain BS variants, suggesting that targeting DHHC7 activity may offer a potential therapeutic strategy for reducing hypertension.

Jennifer Vogel
May 1, 2020; 69:1032-1041
Pharmacology and Therapeutics

VOLUME 295 (2020) PAGES 4079–4092There was an error in the abstract. “The pyridinium cation hampers uptake of OPs into the central nervous system (CNS)” should read as “The pyridinium cation hampers uptake into the central nervous system (CNS).”

Less than two hours after meeting Madison Bumgarner, top Giants prospect Joey Bart found himself catching one of Bumgarner's bullpen sessions after the veteran left-hander approached him and said, "Let's go on No. 1."

Like so many pitchers in Major League camps, Orioles hurlers have extra sets of eyes on them this spring. The Edgertronic cameras, perched on tripods, are set about a stride's length beyond the backfield bullpen mounds at the club's Ed Smith Stadium complex, as conspicuous as the coaches standing cross-armed behind them.

The whitening and loss of brown adipose tissue (BAT) during obesity and aging promote metabolic disorders and related diseases. The imbalance of Ca²⁺ homeostasis accounts for the dysfunction and clearance of mitochondria during BAT whitening. Capsaicin, a dietary factor activating TRPV1, can inhibit obesity induced by high-fat diet (HFD), but whether capsaicin inhibits BAT loss and the underlying mechanism remain unclear. In this study, we determined that the inhibitory effects of capsaicin on HFD-induced obesity and BAT whitening were dependent on the participation of SIRT3, a critical mitochondrial deacetylase. SIRT3 also mediated all of the beneficial effects of capsaicin on alleviating reactive oxygen species generation, elevating mitochondrial activity, and restricting mitochondrial calcium overload induced by HFD. Mechanistically, SIRT3 inhibits mitochondrial calcium uniporter (MCU)-mediated mitochondrial calcium overload by reducing the H3K27ac level on the MCU promoter in an AMPK-dependent manner. In addition, HFD also inhibits AMPK activity to reduce SIRT3 expression, which could be reversed by capsaicin. Capsaicin intervention also inhibited aging-induced BAT whitening through this mechanism. In conclusion, this study emphasizes a critical role of the AMPK/SIRT3 pathway in the maintenance of BAT morphology and function and suggests that intervention in this pathway may be an effective target for preventing obesity- or age-related metabolic diseases.

Premier League Clubs Association (PLCA) vice-chairman Carvel Stewart says that the Red Stripe Premier League (RSPL) could return in July at the earliest. The nation’s top flight has been on hiatus since March, with four games left in the regular...

Welcome to the festive talk evidence, giving you a little EBM to take you into the new year. As always Duncan Jarvies is joined by Helen Macdonald (resting GP and editor at The BMJ) and Carl Heneghan (active GP, director of Oxford University’s CEBM and editor of BMJ Evidence)* This month: (1.20) Carl tells us about new research on treating...

Giulio Marchesini
Aug 1, 2001; 50:1844-1850
Pathophysiology

An application earlier this year by Mahoe Gaming Enterprises Limited (MGEL) has not benefited from any preferential treatment by the Betting, Gaming and Lotteries Commission (BGLC). That was the finding of ex-commissioner of the Integrity...

More than 1 million international students were in the United States in 2015-16, a significant share of them in science, technology, engineering, or math (STEM) fields. While countries increasingly are vying for this population, these individuals face a complex choice upon graduation: to stay or leave? This article examines international STEM students in the United States and the motivations underlying their postgraduation plans.

Although in many countries immigrants fill labor gaps in fields such as agriculture and construction, few legal migration pathways exist for low-skilled workers. As states meet to negotiate a Global Compact for Safe, Orderly, and Regular Migration, this policy brief takes stock of the channels available for such workers to move legally and take up work abroad, highlighting promising practices and policy gaps.

Immigration has driven economic and social development in Australia for more than two centuries. Even as more than one-fourth of the country’s population is foreign born and Australia ranks third among top refugee resettlement countries worldwide, controversy surrounding its hardline treatment of asylum seekers arriving by boat has cast a shadow on its reputation as a welcoming country, as this article explores.

Nehman Lauder
Oct 1, 2005; 23:191-192
Case Studies

Warren Clayton
Mar 1, 2009; 27:52-58
Features

Ingrid Kruse
Apr 1, 2006; 24:91-93
Practical Pointers

Luigi Uccioli
Oct 1, 1995; 18:1376-1378
Short Report

Gregory G. Schwartz
May 1, 2020; 43:1077-1084
Emerging Therapies: Drugs and Regimens

William J. Jeffcoate
Apr 1, 2018; 41:645-652
Perspectives in Care

OBJECTIVE

Topical oxygen has been used for the treatment of chronic wounds for more than 50 years. Its effectiveness remains disputed due to the limited number of robust high-quality investigations. The aim of this study was to assess the efficacy of multimodality cyclical pressure Topical Wound Oxygen (TWO2) home care therapy in healing refractory diabetic foot ulcers (DFUs) that had failed to heal with standard of care (SOC) alone.

The last decade brought 236,658 attendees to the American Dental Association's annual meeting. The ADA will continue to build on that momentum with the ADA FDC Annual Meeting from Oct. 15-18 in Orlando, Florida.

Indianapolis -- Seven-year-old Jordan Randle made a big promise after visiting Give Kids A Smile for the first time during the national kickoff event Feb. 7 in Indianapolis.

Overfill of medication or obturation materials in endodontic treatment can cause permanent neurologic injury, and there are steps clinicians can take to help prevent that, according to an article published in the May issue of The Journal of the American Dental Association.

OBJECTIVE

To determine the effect of tirzepatide, a dual agonist of glucose-dependent insulinotropic polypeptide and glucagon-like peptide 1 receptors, on biomarkers of nonalcoholic steatohepatitis (NASH) and fibrosis in patients with type 2 diabetes mellitus (T2DM).

Swedish asylum policy has taken a restrictionist turn since the country received a record-breaking number of asylum seekers in 2015 and after electoral gains by the nationalist, anti-immigration Sweden Democrats pushed the governing coalition to a harder line. Still, other aspects of the country’s migration policy remain welcoming, as this country profile explores.

This delicious Argentinian confection (also known as Spanish Caramel/milk jam) is a thick caramel milk-based sauce to die for and is so easy to make at home. Use as a filling for tartlets or cakes, serve over ice cream, as a filling for crepes, as a sauce over baked pears or apples or simply eat from a spoon!

Though Colombians displaced by a decades-long civil war found a welcome refuge in Ecuador, life has become more difficult for them in recent years, in part as a result of the influx of Venezuelans seeking safety. This article draws on surveys of migrants in Quito, comparing and contrasting the experiences of Colombians and Venezuelans, and assessing their perceptions of discrimination, victimization, trust in institutions, and hopes for the future.

Large-scale displacement from Venezuela and Nicaragua is reshaping the migration landscape in much of Latin America and the Caribbean. This report, accompanied by the launch of a new Migration Portal offering research and analysis on the region, examines the immigration and integration policy responses of 11 countries, including pathways to legal status and measures to integrate newcomers into schools, health-care systems, and labor markets.

Digging a little deeper into the data from international tests reveals ways in which differences in the content students can access widens math achievement gaps.

Digging a little deeper into the data from international tests reveals ways in which differences in the content students can access widens math achievement gaps.

"A special challenge of hard rock exploration is to identify targets of interest within complex geological settings. Interpretation of the geology can be made from direct geological observations and knowledge of the area, and from 2D or 3D seismic surveys. These interpretations can be developed into 3D geological models that provide the basis for predictions as to likely targets for drilling and/or mining. To verify these predictions we need to simulate 3D seismic wave propagation in the proposed geological models and compare the simulation results to seismic survey data. To achieve this we convert geological surfaces created in an interpretation software package into discretised block models representing the different lithostratigraphic units, and segment these into discrete volumes to which appropriate density and seismic velocity values are assigned. This approach allows us to scale models appropriately for desired wave propagation parameters and to go from local to global geological models and vice versa. Then we use these digital models with forward modelling codes to undertake numerous 3D acoustic wave simulations. Simulations are performed with single shot and with exploding reflector (located on extracted geological surface) configurations" -- Summary.

Dodd, Reg, 1940-

Social problems -- United States.

Volcanoes.

Business enterprises -- Computer networks -- Management.

1733.

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