Feng Xu
Trans. Amer. Math. Soc. 373 (2020), 3515-3539.
Abstract, references and article information

Yu. S. Mishura and H. S. Zhelezniak
Theor. Probability and Math. Statist. 99 (2020), 199-210.
Abstract, references and article information

M. M. Kapustei and P. V. Slyusarchuk
Theor. Probability and Math. Statist. 99 (2020), 101-111.
Abstract, references and article information

To celebrate the 30th anniversary of the Cultural Centre, the Leisure & Cultural Services Department will hold a fun day from noon to 5.30pm on November 9.

The centre’s venue partners, the Hong Kong Chinese Orchestra, the Hong Kong Philharmonic Orchestra, the Hong Kong Ballet and Zuni Icosahedron will use the latest technology in the foyer to present Western and Chinese music, a ballet performance and sound and scene recreation of the former Kowloon-Canton Railway Station.

At the piazza areas, more than 40 dancers will perform works by acclaimed and emerging choreographers and lead visitors to discover every corner of the centre.

Artist Enoch Cheng will curate "Unseen Scene" in the backstage area to display the magic behind a show through music, dance, projections and other special performances.

Additional programmes will include the Stage & Technology Workshop and the 30th anniversary exhibition "Traces of the Past & Future".

Besides free events on the fun day, the centre will hold a celebratory concert at 8pm on November 29 and 30. Pieces specially selected from the repertoire of the centre's opening concert 30 years ago will be presented.

Click here for details.

The East Kowloon Cultural Centre Public Artwork Commissioning Project is inviting artists, designers and architects to create an art landscape for the centre.

Presented by the Leisure & Cultural Services Department and organised by the Art Promotion Office, the project endeavors to capture and showcase the past, present and future of East Kowloon.

The commissioned artworks will represent five themes - memory, impression, moment, dream and imagination - aiming to display the district’s changing nature, and to manifest the local community’s cultural sustainability, aspirations and dreams.

Interested participants must submit their preliminary proposal with their curriculum vitae, documentation of their previous artwork and the artistic concept of the proposed artwork.

All proposals must be delivered to the centre’s Public Art Project Management Team at G/F, 50-54 Lok Ku Road, Sheung Wan before 7pm on May 4.

Participants shortlisted by the selection panel are required to submit detailed proposals before 7pm on June 30 for the next stage of the selection process.

Up to three proposals shall be chosen by the selection panel for commissioning and installing in the centre.

The Leisure & Cultural Services Department launched a one-stop online resources centre today for the public to view or participate in multi-faceted leisure and cultural activities from the comfort of their homes.

The online resources centre offers demonstrations of home exercises as well as videos of exercise demonstrations and Healthy Exercise for All Campaign interactive games.

The information portal carries knowledge on the plants and animals at the Zoological & Botanical Gardens, old and valuable trees at the department's major parks and colourful Hong Kong Flower Show archives.

The Museum of Art and the Heritage Museum are collaborating with the Google Arts & Culture Project to showcase exhibits in a digital format.

There are also virtual exhibitions that explore previous fascinating collections at the History Museum and the Science Museum.

While extensive content from intangible cultural heritage and modern arts integrating into life from Oi! is also included.

The Hong Kong Public Libraries offers vast e-resources allowing people to explore fun reading at home.

On the performing arts front, digital content covers concert archives from the Hong Kong Philharmonic Orchestra, Hong Kong Chinese Orchestra and Hong Kong Sinfonietta.

Secretary for Education Kevin Yeung said all the examination centres for the Hong Kong Diploma of Secondary Education (DSE) Examination are well prepared to provide a very safe environment for candidates to take the exams.

Mr Yeung made the statement when asked by reporters this morning about the arrangements schools have made to prepare for the DSE to be held on April 24.

He said: “In terms of the distance between the seats, in terms of all the procedures for cleansing, and also the detailed arrangements including the toilet arrangement and other things, all the schools, all the examination centres, are well prepared to provide a very safe environment for our candidates to take the examinations.”

Regarding school resumption, Mr Yeung said the Government has not made any firm decision nor set any deadline for schools to resume classes.

Chief Secretary Matthew Cheung today visited Queen Elizabeth School to inspect the preparatory work of an examination centre for the Hong Kong Diploma of Secondary Education (DSE) Examination.

Mr Cheung was briefed on anti-epidemic precautionary measures for candidates and examination personnel before they enter the centres.

They will be required to wear masks, make health declarations, undergo temperature checks, disinfect the soles of their shoes and clean their hands with alcohol-based sanitiser.

He then visited the school hall to understand the preparation required for an examination centre, such as disinfection and widening the distance between candidates’ seats to 1.8m as much as possible.

The Chief Secretary also learnt about the arrangements for candidates during the sessional break and the use of washrooms to help ensure that social distancing is maintained.

Mr Cheung was pleased to know that the Education Bureau had earlier distributed masks to candidates and made available about 200,000 bottles of alcohol-based sanitiser for candidates at examination centres.

The bureau has also set fallback dates, should the DSE examination be halted if the epidemic situation worsens.

He thanked the bureau, relevant government departments, the Examinations & Assessment Authority, principals, teachers and school staff for the additional work they have done to protect the candidates’ health and safety.

He encouraged the some 50,000 candidates to tackle the examinations positively and optimistically and reminded them to heighten their anti-epidemic awareness and strictly follow examination arrangements.

Additionally, Mr Cheung appealed to all employers to allow their staff to follow flexible working hours to divert passenger flows on public transport during the morning peak hours between 7am and 8am, thus enabling candidates to reach examination centres on time.

Type 2 diabetes mellitus (T2DM) is characterized by impaired glucose-stimulated insulin secretion and increased peripheral insulin resistance. Unremitting endoplasmic reticulum (ER) stress can lead to beta-cell apoptosis and has been linked to type 2 diabetes. Although many studies have attempted to link ER stress and T2DM, the specific effects of ER stress on beta-cell function remain incompletely understood. To determine the interrelationship between ER stress and beta-cell function, here we treated insulin-secreting INS-1(832/13) cells or isolated mouse islets with the ER stress–inducer tunicamycin (TM). TM induced ER stress as expected, as evidenced by activation of the unfolded protein response. Beta cells treated with TM also exhibited concomitant alterations in their electrical activity and cytosolic free Ca2+ oscillations. As ER stress is known to reduce ER Ca2+ levels, we tested the hypothesis that the observed increase in Ca2+ oscillations occurred because of reduced ER Ca2+ levels and, in turn, increased store-operated Ca2+ entry. TM-induced cytosolic Ca2+ and membrane electrical oscillations were acutely inhibited by YM58483, which blocks store-operated Ca2+ channels. Significantly, TM-treated cells secreted increased insulin under conditions normally associated with only minimal release, e.g. 5 mm glucose, and YM58483 blocked this secretion. Taken together, these results support a critical role for ER Ca2+ depletion–activated Ca2+ current in mediating Ca2+-induced insulin secretion in response to ER stress.

(Geological Society of America) The annual meeting of The Geological Society of America's North-Central Section, originally scheduled to take place in Duluth, Minnesota, will be held virtually on May 18-19, 2020, with technical sessions in the morning and student programming in the afternoon. The online meeting is open and available to everyone for free. No registration is required.

Mozart once called the pipe organ the “king of instruments” and Hong Kong has musical royalty sitting in the heart of Tsim Sha Tsui.

It is hard to miss the pipe organ when you are inside the Cultural Centre Concert Hall. With its four manuals, 93 stops and 8,000 pipes, it can produce an exceptional array of timbre and volume.

“The pipe organ is the ‘pearl’ of a concert hall,” explained pipe organist Chiu Siu-ling.

“Its enormous range of sounds, coupled with a huge variety of tone colours, creates a remarkable musical experience equivalent to that of an orchestra. It is the king of instruments.”

Star performer

The four-storey tall pipe organ was hand-made by famed Austrian manufacturer Rieger Orgelbau and installed when the Cultural Centre was built 30 years ago. It has attracted several world-renowned performers to Hong Kong over the years.

“When we built it in 1989, it was the first, huge mechanically operated organ in Asia. I think it is still our biggest organ we have ever built in Asia,” Rieger pipe organ maintenance technician Gerhard Pohl said.

He added that the instrument is also remarkably versatile.

“There are many organs they are built just for one musical style. On this organ, you can play everything, even jazz music.”

Mr Pohl comes to Hong Kong once a year to give the 30-year-old organ its annual health check. In between visits by the manufacturer’s technicians, William Wen ensures the Cultural Centre’s star performer remains in tip-top condition.

Top tuner

Mr Wen is Hong Kong’s only pipe organ maintenance technician. He carries out routine checks on the instrument and tunes it every month.

“Keeping it in tune is my responsibility. I take care of it.”

Mr Wen was one of the first in Hong Kong to learn the instrument in the 1980s. He became interested in pipe organ maintenance after a visit to an organ manufacturing company in Europe.

He recalled that in the ‘80s, organists in Hong Kong were few and far between. He was called upon to test the Cultural Centre organ before the grand opening, making him one of the first organists to play it.

“It was dark in the hall, so at first, I only noticed the organ’s keys. When I got closer, I was astounded by just how big the instrument was.”

Mr Wen takes up to five hours per maintenance visit to thoroughly check the pipes and tune the organ. He explained that the organ is regularly updated and was fitted with an electrical coupler system, providing greater flexibility in switching between lighter and stronger key actions as desired by the player.

“It has been updated a few times. In 2010, the organ was installed with an electrical coupler system. I used to get someone to press the keys for me while I would tune it from inside. But now, I just need a mobile phone on which I can tune it by myself.”

Musical legacy

To promote organ music and nurture local organists, the Cultural Centre has been organising the “King of the Instruments” Pipe Organ Education Series annually since 1999. Now the programme’s principal instructor, Ms Chiu has been teaching from the outset.

“People are not allowed to touch the instrument in a lot of other concert halls, and they seldom hold pipe organ concerts. This is actually not good for the organ. It has to be played to keep it in good condition or the keys and parts will become hard and old. This inspires me teach and let more and more musicians learn and play the instrument,” Ms Chiu explained.

More than 300 organists have so far been trained on the Cultural Centre’s organ. But it has also played something other than music - it has played Cupid too.

Like-minded musicians

Pipe organist Simon Chan met his wife, Shirley Cheng, through the programme.

“I joined the Pipe Organ Education Series in 2000. After that, I continued learning the organ with Ms Chiu and eventually became one of the course tutors. I met my wife in 2003 on the course.”

Ms Cheng was also a student on the course. She switched majors from information technology to music and that fateful decision led to meeting her husband.

“He asked me to watch him play. He was playing a big piece which was powerful and loud, and that was when I fell for his charms.”

The couple decided to embark on a life journey together and now hope to pass on their love of music and the pipe organ to their children.

“I wish for my kids to learn music too and to find out more about the pipe organ. This instrument brought their father and mother together and I want them to know our story,” said Ms Cheng.

The organist-music teacher duo also hopes to share the joy of the pipe organ with the rest of the community.

Children gain a valuable insight into Hong Kong’s waterworks by directing the flow of water at an attraction designed to emulate the water cycle at the Water Supplies Department’s brand new H2OPE Centre.

They learn how rain passes through catchwaters in mountains and is filtered and distributed to people’s homes at the attraction, one of the 54 games or displays at the water education centre.

Kids can also try their hand at a fishing simulator to learn about tips and advice on fishing in reservoirs and discover ways to recycle and save water at other exhibits of the 720-sq m centre, which opened in December.

“It is extremely fun. We do not have this at school. I know how to save water now,” student Kim Lam said.

“Usually, we sit in a classroom and answer questions. But now we can learn about water in Hong Kong by playing games. It is excellent,” fellow student Alan Zeng added.

Children can also watch immersive videos at the centre’s 3D dome theatre.

Deeper understanding

The department hopes the centre will raise public awareness about water conservation.

“Its exhibits, live demonstrations and interactive games help visitors gain more insight into Hong Kong’s water resources,” Water Supplies Department Senior Engineer Irene Tong explained.

People can also visit the city’s important waterworks facilities such as the Waterworks Heritage Trails and the High Island Reservoir in Sai Kung, by joining the department’s Excursion with Water Save Dave. 

Water Save Dave is the department’s mascot to help promote a water conservation culture in the community.

Water Supplies Department Engineer Fion Chan said: “Water Save Dave is blue and shaped like a water drop to encourage us to cherish every single drop of water.

“We hope that guided tours of waterworks facilities will raise the public’s awareness about water resources and conservation.”

Do you know which main gases are contained in the composition of air? Under climate change and global warming, carbon dioxide ...

Fundraising efforts, along with a generous donation from Beyond Meat, founded by Ethan Brown ’08, helps restaurant P.S. Kitchen, owned by April Tam Smith ’10 and Graham Smith ’21, provide meals to healthcare workers.

We take you through the steps to clear your old devices from Sophos Central, so you've got more time to focus on the devices that matter.

Research Event

Event participants

Osamah Al Rawhani, Deputy Director, Sana’a Center for Strategic Studies
Moderator: Nadim Houry, Executive Director, Arab Reform Initiative

Sodium–glucose cotransport 2 inhibitors (SGLT2i) lower plasma glucose but stimulate endogenous glucose production (EGP). The current study examined the effect of dapagliflozin on EGP while clamping plasma glucose, insulin, and glucagon concentrations at their fasting level. Thirty-eight patients with type 2 diabetes received an 8-h measurement of EGP ([3-³H]-glucose) on three occasions. After a 3-h tracer equilibration, subjects received 1) dapagliflozin 10 mg (n = 26) or placebo (n = 12); 2) repeat EGP measurement with the plasma glucose concentration clamped at the fasting level; and 3) repeat EGP measurement with inhibition of insulin and glucagon secretion with somatostatin infusion and replacement of basal plasma insulin and glucagon concentrations. In study 1, the change in EGP (baseline to last hour of EGP measurement) in subjects receiving dapagliflozin was 22% greater (+0.66 ± 0.11 mg/kg/min, P < 0.05) than in subjects receiving placebo, and it was associated with a significant increase in plasma glucagon and a decrease in the plasma insulin concentration compared with placebo. Under glucose clamp conditions (study 2), the change in plasma insulin and glucagon concentrations was comparable in subjects receiving dapagliflozin and placebo, yet the difference in EGP between dapagliflozin and placebo persisted (+0.71 ± 0.13 mg/kg/min, P < 0.01). Under pancreatic clamp conditions (study 3), dapagliflozin produced an initial large decrease in EGP (8% below placebo), followed by a progressive increase in EGP that was 10.6% greater than placebo during the last hour. Collectively, these results indicate that 1) the changes in plasma insulin and glucagon concentration after SGLT2i administration are secondary to the decrease in plasma glucose concentration, and 2) the dapagliflozin-induced increase in EGP cannot be explained by the increase in plasma glucagon or decrease in plasma insulin or glucose concentrations.

Purpose: The aim of this retrospective multicentric study was to develop and evaluate a prognostic FDG PET/CT radiomics signature in early-stage non-small cell lung cancer (NSCLC) patients treated with stereotactic radiotherapy (SBRT). Material and Methods: Patients from 3 different centers (n = 27, 29 and 8) were pooled to constitute the training set, whereas the patients from a fourth center (n = 23) were used as the testing set. The primary endpoint was local control (LC). The primary tumour was semi-automatically delineated in the PET images using the Fuzzy locally adaptive Bayesian algorithm, and manually in the low-dose CT images. A total of 184 IBSI-compliant radiomic features were extracted. Seven clinical and treatment parameters were included. We used ComBat to harmonize radiomic features extracted from the four institutions relying on different PET/CT scanners. In the training set, variables found significant in the univariate analysis were fed into a multivariate regression model and models were built by combining independent prognostic factors. Results: Median follow-up was 21.1 (1.7 – 63.4) and 25.5 (7.7 – 57.8) months in training and testing sets respectively. In univariate analysis, none of the clinical variables, 2 PET and 2 CT features were significantly predictive of LC. The best predictive models in the training set were obtained by combining one feature from PET, namely information correlation 2 (IC2) and one from CT (Flatness), reaching a sensitivity of 100% and a specificity of 96%. Another model combining 2 PET features (IC2 and Strength), reached sensitivity of 100% and specificity of 88%, both with an undefined hazard ratio (HR) (p<0.001). The latter model obtained an accuracy of 0.91 (sensitivity 100%, specificity 81%), with a HR undefined (P = 0.023) in the testing set, however other models relying on CT radiomics features only or the combination of PET and CT features failed to validate in the testing set. Conclusion: We showed that two radiomic features derived from FDG PET were independently associated with LC in patients with NSCLC undergoing SBRT and could be combined in an accurate predictive model. This model could provide local relapse-related information and could be helpful in clinical decision-making.

Background: Accurate definition of the extent and severity of left-ventricular assist device (LVAD) infection may facilitate therapeutic decision making and targeted surgical intervention. Here, we explore the value of ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) for guidance of patient management. Methods: Fifty-seven LVAD-carrying patients received 85 whole-body ¹⁸F-FDG PET/CT scans for the work-up of device infection. Clinical follow-up was obtained over a period of up to two years. Results: PET/CT showed various patterns of infectious involvement of the 4 LVAD components: driveline entry point (77% of cases), subcutaneous driveline path (87%), pump pocket (49%) and outflow tract (58%). Driveline smears revealed staphylococcus or pseudomonas strains as the underlying pathogen in a majority of cases (48 and 34%, respectively). At receiver-operating characteristics analysis, an ¹⁸F-FDG standardized uptake value (SUV) >2.5 was most accurate to identify smear-positive driveline infection. Infection of 3 or all 4 LVAD components showed a trend towards lower survival vs infection of 2 or less components (P = 0.089), while involvement of thoracic lymph nodes was significantly associated with adverse outcome (P = 0.001 for nodal SUV above vs below median). Finally, patients that underwent early surgical revision within 3 months after PET/CT (n = 21) required significantly less inpatient hospital care during follow-up when compared to those receiving delayed surgical revision (n = 11; p<0.05). Conclusion: Whole-body ¹⁸F-FDG PET/CT identifies the extent of LVAD infection and predicts adverse outcome. Initial experience suggests that early image-guided surgical intervention may facilitate a less complicated subsequent course.

Acidosis is a key driver for many diseases, including cancer, sepsis, and stroke. The spatiotemporal dynamics of dysregulated pH across disease remains elusive and current diagnostic strategies do not provide localization of pH alterations. We sought to explore if PET imaging using hydrophobic cyclic peptides that partition into the cellular membrane at low extracellular pH (denoted as "pHLIC") can permit accurate in vivo visualization of acidosis. Methods: Acid-sensitive cyclic peptide c[E4W5C] pHLIC was conjugated to bifunctional maleimide-NO2A and radiolabeled with copper-64 (t1/2 = 12.7 h). C57BL/6J mice were administered LPS (15 mg/kg) or saline (vehicle) and serially imaged with [⁶⁴Cu]Cu-c[E4W5C] over 24 h. Ex vivo autoradiography was performed on resected brain slices and subsequently stained with cresyl violet to enable high-resolution spatial analysis of tracer accumulation. A non- pH-sensitive cell-penetrating control peptide (c[R4W5C]) was used to confirm specificity of [⁶⁴Cu]Cu-c[E4W5C]. CD11b (macrophage/microglia) and TMEM119 (microglia) immunostaining was performed to correlate extent of neuroinflammation with [⁶⁴Cu]Cu-c[E4W5C] PET signal. Results: [⁶⁴Cu]Cu-c[E4W5C] radiochemical yield and purity was >95% and >99% respectively, with molar activity >0.925 MBq/nmol. Significantly increased [⁶⁴Cu]Cu-c[E4W5C] uptake was observed in LPS-treated mice (vs. vehicle) within peripheral tissues including blood, lungs, liver, and small intestines (P < 0.001-0.05). Additionally, there was significantly increased [⁶⁴Cu]Cu-c[E4W5C] uptake in the brains of LPS-treated animals. Autoradiography confirmed increased uptake in the cerebellum, cortex, hippocampus, striatum, and hypothalamus of LPS-treated mice (vs. vehicle). Immunohistochemical (IHC) analysis revealed microglial/macrophage infiltrate, suggesting activation in brain regions containing increased tracer uptake. [⁶⁴Cu]Cu-c[R4W5C] demonstrated significantly reduced uptake in the brain and periphery of LPS mice compared to the acid-mediated [⁶⁴Cu]Cu-c[E4W5C] tracer. Conclusion: Here, we demonstrate that a pH-sensitive PET tracer specifically detects acidosis in regions associated with sepsis-driven pro-inflammatory responses. This study suggests that [⁶⁴Cu]Cu-pHLIC is a valuable tool to noninvasively assess acidosis associated with both central and peripheral innate immune activation.

The accuracy of lutetium-177 (¹⁷⁷Lu) radiotracer concentration measurements using quantitative clinical software was determined by comparing in vivo results for a digital solid-state cadmium-zinc-telluride SPECT/CT (single photon emission computed tomography / x-ray computed tomography) system to in vitro sampling. First, image acquisition parameters were assessed for an International Electrotechnical Commission (IEC) body phantom emulating clinical count rates loaded with a "lung" insert and 6 hot spheres with a 12:1 target-to-background ratio of ¹⁷⁷Lu solution. Then, the data of 28 whole-body SPECT/CT scans of 7 patients who underwent ¹⁷⁷Lu prostate membrane antigen (¹⁷⁷Lu-PSMA) radioligand therapy was retrospectively analyzed. Three users analyzed SPECT/CT images for in vivo urinary bladder radiotracer uptake using quantitative software (Q.Metrix, GE Healthcare). In vitro radiopharmaceutical concentrations were calculated using urine sampling obtained immediately after each scan, scaled to standardized uptake values (SUVs). Any in vivo/in vitro identity relations were determined by linear regression (ideally slope=1, intercept=0), within a 95 % confidence interval (CI). Phantom results demonstrated lower quantitative error for acquisitions using the 113 keV ¹⁷⁷Lu energy peak rather than including the 208 keV peak, given that only low-energy collimation was available in this camera configuration. In the clinical study, 24 in vivo/in vitro pairs were eligible for further analysis, having rejected 4 as outliers (via Cook’s distance calculations). All linear regressions (R2 ≥ 0.92, P<0.0001) provided identity in vivo/in vitro relations (95 % CI), with SUV averages from all users giving a slope of 1.03±0.09, an intercept of –0.25±0.64 g/mL, and an average residual difference of 20.4 %. Acquiring with the lower energy ¹⁷⁷Lu energy peak, solid-state SPECT/CT imaging provides an accuracy to within ~20 % for in vivo urinary bladder radiotracer concentrations. This non-invasive in vivo quantitation method can potentially improve diagnosis, improve patient management and treatment response assessment, and provide data essential to ¹⁷⁷Lu dosimetry.

Cancer Survival is related to tumor volume. FDG PET measurement of tumor volume holds promise but is not yet a clinical tool. Measurements come in two forms: the total lesion volume (TLV) based on the number of voxels in the tumor and secondly the total lesion glycolysis (TLG) which is the TLV multiplied by the average SUL per voxel of the tumor (SUL is the standardize uptake value normalized for lean mass). In this study we measured tumor volume in patients with malignant pleural mesothelioma (MPM). METHODS: A threshold-based program in IDL was developed to measure tumor volume in FDG PET images. 19 patients with malignant pleural mesothelioma (MPM) were studied before and after two cycles (6 weeks) of chemo-immunotherapy. Measurements included the total lesion volume (TLV), Total Lesion Glycolysis (TLG), the sum of the SULs in the tumor (SUL- total), a measure of total FDG uptake, and the average SUL per voxel. RESULTS: Baseline MPM volumes (TLV) ranged from 11 to 2610 cc. TLG values ranged from 32 to 8552 SUL-cc and were strongly correlated with TLV. While tumor volumes ranged over 3 orders of magnitude, the average SUL per voxel, SUL-average, stayed within a narrow range of 2.4 to 5.3 units. Thus, TLV was the major component of TLG while SUL-average was a minor component and was essentially constant. Further evaluation of SUL-average showed that in this cohort it’s two components SUL-total and tumor volume changed in parallel and were strongly correlated, r= 0.99, p<.01. Thus, whether the tumors were large or small, the FDG uptake as measured by SUL-total was proportional to the total tumor volume. Conclusion: TLG equals TLV multiplied by the average SUL per voxel, essentially TLV multiplied by a constant. Thus TLG, commonly considered a measure of "metabolic activity" in tumors, is also in this cohort a measure of tumor volume. The constancy of SUL per voxel is due to FDG uptake being proportional to tumor volume. Thus, in this study, the FDG uptake was also a measure of volume.

C-X-C chemokine receptor 4 is a transmembrane chemokine receptor involved in growth, survival, and dissemination of cancer, including aggressive B-cell lymphoma. Magnetic resonance imaging (MRI) is the standard imaging technology for central nervous system involvement of B-cell lymphoma and provides high sensitivity but moderate specificity. Therefore, novel molecular and functional imaging strategies are urgently required. Methods: In this proof-of-concept study, 11 patients with lymphoma of the CNS (CNSL, n = 8 primary and n = 3 secondary involvement) were imaged with the CXCR4-directed positron emission tomography (PET) tracer ⁶⁸Ga-Pentixafor. To evaluate the predictive value of this imaging modality, treatment response, as determined by MRI, was correlated with quantification of CXCR4 expression by ⁶⁸Ga-Pentixafor PET in vivo before initiation of treatment in 7 of 11 patients. Results: ⁶⁸Ga-Pentixafor-PET showed excellent contrast characteristics to the surrounding brain parenchyma in all patients with active disease. Furthermore, initial CXCR4 uptake determined by PET correlated with subsequent treatment response as assessed by MRI. Conclusion: ⁶⁸Ga-Pentixafor-PET represents a novel diagnostic tool for central nervous system lymphoma with potential implications for theranostic approaches as well as response and risk assessment.

31 October 2019

Trade between Central and Eastern Europe and sub-Saharan Africa has increased significantly in the last decade and a half. There is a strong case to be made for greater economic re-engagement, especially in terms of investment, that has the potential to support inclusive growth in both regions.

Research Event