Robust Institutional Support and Collaboration Between Summer Training Programs in Cancer and Biomedicine Drive the Pivot to a Virtual Format in Response to the COVID Pandemic

Summer internships serve important roles in training the next generation of biomedical researchers and healthcare providers through laboratory and clinical experiences that excite trainees about these fields and help them make informed decisions about career paths. The SARS-CoV-2 (COVID) pandemic and associated physical distancing restrictions precluded implementation of traditional in-person summer curricula and led to the cancellation of many internships across the USA. COVID-related disruptions also created opportunities for trainees to engage in remote research, become proficient in online learning platforms, and explore multidisciplinary topics. These skills are highly relevant to trainees as virtual interfaces occupy an increasingly mainstream role in their professional paths. The response to the COVID pandemic required real-time adaptations at all levels for major biomedical institutions including the University of Maryland Baltimore (UMB). Pivoting summer programs to a virtual format as part of this response provided a "teachable moment" to expose trainees to the innovation and resilience that are essential components of the biomedical profession. UMB summer programs, which span diverse biomedical disciplines from cancer research to diabetes, consolidated resources and identified mentors with online research projects to develop a robust virtual curriculum. Herein, data from a cancer-focused internship illustrate the collaborative adaptations to established components and creation of new learning modules in the transition to, and implementation of, online training. Outcomes are presented in the context of the COVID pandemic and significant societal issues that arose in the summer of 2020. The utility of virtual components and their impact on future programs is discussed.

Polycomb contraction differentially regulates terminal human hematopoietic differentiation programs

Background

Lifelong production of the many types of mature blood cells from less differentiated progenitors is a hierarchically ordered process that spans multiple cell divisions. The nature and timing of the molecular events required to integrate the environmental signals, transcription factor activity, epigenetic modifications, and changes in gene expression involved are thus complex and still poorly understood. To address this gap, we generated comprehensive reference epigenomes of 8 phenotypically defined subsets of normal human cord blood.

Results

We describe a striking contraction of H3K27me3 density in differentiated myelo-erythroid cells that resembles a punctate pattern previously ascribed to pluripotent embryonic stem cells. Phenotypically distinct progenitor cell types display a nearly identical repressive H3K27me3 signature characterized by large organized chromatin K27-modification domains that are retained by mature lymphoid cells but lost in terminally differentiated monocytes and erythroblasts. We demonstrate that inhibition of polycomb group members predicted to control large organized chromatin K27-modification domains influences lymphoid and myeloid fate decisions of primary neonatal hematopoietic progenitors in vitro. We further show that a majority of active enhancers appear in early progenitors, a subset of which are DNA hypermethylated and become hypomethylated and induced during terminal differentiation.

Conclusion

Primitive human hematopoietic cells display a unique repressive H3K27me3 signature that is retained by mature lymphoid cells but is lost in monocytes and erythroblasts. Intervention data implicate that control of this chromatin state change is a requisite part of the process whereby normal human hematopoietic progenitor cells make lymphoid and myeloid fate decisions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12915-022-01315-1.

Revealing the Sole Impact of Acceptor's Molecular Conformation to Energy Loss and Device Performance of Organic Solar Cells through Positional Isomers

Two new fused-ring electron acceptor (FREA) isomers with nonlinear and linear molecular conformation, m-BAIDIC and p-BAIDIC, are designed and synthesized. Despite the similar light absorption range and energy levels, the two isomers exhibit distinct electron reorganization energies and molecular packing motifs, which are directly related to the molecular conformation. Compared with the nonlinear acceptor, the linear p-BAIDIC shows more ordered molecular packing and higher crystallinity. Furthermore, p-BAIDIC-based devices exhibit reduced nonradiative energy loss and improved charge transport mobilities. It is beneficial to enhance the open-circuit voltage (V_OC ) and short-current current density (J_SC ) of the devices. Therefore, the linear FREA, p-BAIDIC yields a relatively higher efficiency of 7.71% in the binary device with PM6, in comparison with the nonlinear m-BAIDIC. When p-BAIDIC is incorporated into the binary PM6/BO-4Cl system to form a ternary system, synergistic enhancements in V_OC , J_SC , fill factor (FF), and ultimately a high efficiency of 17.6% are achieved.

Strategies for the application of metal-organic frameworks in catalytic reactions

Efficient catalysts play crucial roles in various organic reactions and polymerization. Metal–organic frameworks (MOFs) have the merits of ultrahigh porosity, large surface area, dispersed polymetallic sites and modifiable linkers, which make them promising candidates for catalyzation. This review primarily summarizes the recent research progress on diverse strategies for tailoring MOFs that are endowed with excellent catalytic behavior. These strategies include utilizing MOFs as nanosized reaction channels, metal nodes decorated as catalytic active sites and the modification of ligands or linkers. All these make them highly attractive to various applications, especially in catalyzing organic reactions or polymerizations and they have proven to be effective catalysts for a wide variety of reactions. MOFs are still an evolving field with tremendous prospects; therefore, through the research and development of more modification and regulation strategies, MOFs will realize their wider practical application in the future.

Metal–organic frameworks (MOFs) are promising candidates for catalyzation. This review primarily summarized the recent research progress in diverse strategies for tailoring MOFs which are endowed with more excellent catalytic behavior.

A turn-on NIR fluorescence sensor for gossypol based on Yb-based metal-organic framework

The development of analytical method for selective and sensitive detection of gossypol (Gsp), an extraction from the cotton plants, is important but still challenging in food safety and medical field. Herein, we reported a turn-on near infrared (NIR) fluorescence detection strategy for Gsp based on a metal-organic framework (MOF), QBA-Yb, which was prepared from 4,4'-(quinolone-5, 8-diyl) benzoate with Yb(NO₃)₃·5H₂O by solvothermal synthesis. The Gsp acted as another "antenna" to sensitize the luminescence of Yb³⁺, leading to the turn-on NIR emission upon 467 nm excitation. As Gsp concentration increased, the NIR emission at 973 nm enhanced gradually, thus enabling highly sensitive Gsp detection in a turn-on way. The experiment and theoretical calculation results revealed the presence of strong hydrogen bonds between Gsp molecules and the MOF skeleton. The developed QBA-Yb probe showed excellent characteristics for detection of Gsp molecules, accompanied by wide linear range (5-160 μg/mL), low detection limit (0.65 μg/mL) and short response time (within 10 min). We have further demonstrated that the QBA-Yb probe was successfully applied for the determination of Gsp in real samples of cottonseeds.

[Prenatal diagnosis and clinical outcomes of 297 fetuses with conotruncal defects]

Objective: To analyze the prenatal diagnosis results and pregnancy outcomes of conotruncal defects (CTD) fetuses, and to explore the correlation between the CTD and chromosome diseases. Methods: A total of 297 cases of invasive prenatal diagnosis and chromosome analysis were collected at the Prenatal Diagnosis Center of Guangzhou Women and Children's Medical Center due to CTD from January 1st, 2011 to December 31th, 2019. According to ultrasonic diagnosis, CTD fetuses were divided into 6 subtypes: tetralogy of Fallot (109 cases), pulmonary atresia (30 cases), transposition of the great arteries (77 cases), double outlet right ventricle (53 cases), truncus arteriosus (14 cases) and interrupted aortic arch (14 cases). According to whether they were combined with intracardiac or extracardiac abnormalities, they were divided into simple group (134 cases), combined with other intracardiac abnormalities group (86 cases), combined with extracardiac abnormalities group (20 cases), combined with intracardiac and extracardiac abnormalities group (37 cases) and only combined with ultrasound soft marker group (20 cases), the last 4 groups were referred as non-simple types. The chromosome test results and pregnancy outcomes of each type and group were analyzed retrospectively. Results: Among the 297 CTD fetuses, the chromosome abnormality rate was 17.5% (52/297). There were 21 cases of abnormal chromosome number, 28 cases of pathogenetic copy number variantions and 3 cases of mosaics. All the 19 cases of micropathogenic fragments smaller than 5 Mb were detected by chromosomal microarray analysis (CMA). Among all the subtypes of CTD, the chromosomal abnormality rate of truncus arteriosus was the highest, at 7/14; while the rate of transposition of the great arteries was the lowest, at 5.2% (4/77). There were significant differences in the rate of chromosomal abnormalities between simple and non-simple types [10.4% (14/134) vs 23.3% (38/163); χ²=8.428, P=0.004]. In each group, the chromosomal abnormality rate was the highest in the combined with intracardiac and extracardiac abnormalities group, at 37.8% (14/37), and the lowest in the simple group, at 10.4% (14/134). There was no significant difference in the rate of chromosomal abnormalities in all subtypes of simple group (all P>0.05). Among 112 cases of live birth, 1 case was 22q11.2 microdeletion syndrome, 5 cases of postnatal clinical diagnosis and prenatal ultrasound diagnosis were not completely consistent, 5 cases died after birth. Conclusions: The incidence of chromosomal abnormalities is high in fetuses with CTD. CTD fetuses with concurrent extrapardiac malformations are more likely to incorporate chromosomal abnormalities. CMA technology could be used as a first-line genetic detection method for CTD. After excluding chromosomal abnormalities, most of the children with CTD have good prognosis.

Commercially available palladium salts as practical and green single-component catalysts in the coordination polymerization of 1-chloro-2-phenylacetylenes in air

Commercially available Pd salts serve as single-component catalysts for coordination polymerization of 1-chloro-2-phenylacetylenes, which affords a new design concept of metal catalysts for coordination polymerization of disubstituted alkynes.

[Effect of metformin and rosiglitazone in non-obese polycystic ovary syndrome women with insulin resistance]

Objective: To investigate effects of metformin and rosiglitazone in non-obese polycystic ovary syndrome (PCOS) women with insulin resistance. Methods: Totally 200 non-obese PCOS women with insulin resistance in West China Second Hospital of Sichuan University were enrolled into this study from Sep. 2013 to Jun. 2016, and were randomly divided into two treatment groups: metformin group (1 500 mg/d) and rosiglitazone group (4 mg/d). The treatment lasted for 6 months. Their clinical and biochemical parameters were collected and compared. Results: In both groups, menstrual cycles [metformin group (37±4) days, rosiglitazone group (35±4) days] were shorter after treatment for 6 months (both P<0.01). After treatment for 6 months, body mass index [metformin group (21.6±1.6) kg/m², rosiglitazone group (21.7±1.7) kg/m²] decreased in both groups (both P<0.01); decreased LH/FSH ratio (metformin group 1.67±0.80, rosiglitazone group 1.70±0.83) was also observed (both P<0.05). After treatment for 6 months, fasting insulin level [metformin group (13.5±5.1) mU/L, rosiglitazone group (12.7±5.6) mU/L] and homeostasis model assessment-insulin resistance index (metformin group 3.0±1.2, rosiglitazone group 2.8±1.2) were decreased in both groups (all P<0.01). Conclusions: For non-obese PCOS insulin resistance patients, screening of anthropometric and metabolic parameters is necessary. For PCOS with insulin resistance, lifestyle plus insulin sensitizers such as metformin could improve their clinical symptoms, correct the biochemical and metabolic dysfunction.

The production of single cell protein from biogas slurry with high ammonia-nitrogen content by screened Nectaromyces rattus

In this study, a novel method was proposed to obtain single cell protein (SCP) in yeast by using biogas slurry as culture medium. The results show that Nectaromyces rattus was the most efficient at producing SCP among the 7 different yeasts studied. Acetic acid was a better pH regulator than hydrochloric acid. After culture with the initial NH₄⁺-N concentration 2,000 mg/L, C/N ratio 6:1, the initial pH 5.50 and rotation speed of 200 rpm, a total cell dry weight of 12.58 g/L with 35.96% protein content was obtained. Nineteen amino acids accounted for 46.85% of cell dry weight, and proline content was as high as 12.0% of the cell dry weight. However, sulfur-containing amino acids, including methionine and cystine, were deficient. Further research should focus on the high cell density culture to increase SCP production.

[Preliminary practice of multidisciplinary cooperative vaccination management model for pediatric patients with hematological and oncological diseases]

Objective: To preliminarily establish the multidisciplinary cooperative vaccination management model for pediatric patients with hematological and oncological diseases, and to explore its feasibility. Methods: In this prospective study a total of 150 children with hematological and oncological diseases visited immunization clinic of Shanghai Children's Medical Center from March 2017 to August 2018 were enrolled in this study. After establishing the multidisciplinary team, designing vaccination plan, staff training, implementation and quality control, a multidisciplinary immunization clinic was set up and the vaccination plan were implemented. The implementation rate of vaccination immunization, the HBsAb level and serum hepatitis B surface antibody (HBsAb) level before and after treatment, the HBsAb level and serum immunoglobulin G antibody (IgG) levels of measles, mumps, rubella (MMR) before and 6 months after immunization, the vaccine-related adverse reactions were assessed prospectively. Chi-square test or Fisher exact test was used to compare the differences of antibody level. Results: A total of 124 cases had been vaccinated as planned, with a coverage rate of 82.7%. Among these cases, the difference of HBsAb positive rate before and after treatment was significant (62.9% (78/124) vs.13.7% (17/124), χ²= 63.489, P<0.01). In 64 cases that completed three doses of hepatitis B immunization, there was a significant difference in HBsAb positive rate before and 6 months after immunization (6.3% (4/64) vs. 98.4% (63/64), P<0.01). In 40 cases that completed MMR immunization, the IgG antibody positive rate for measles (22.5% (9/40) vs. 82.5% (33/40), χ²=31.746,P<0.01), mumps (22.5% (9/40) vs.82.5% (33/40), χ²=28.872,P<0.01), rubella (25.0% (10/40) vs.62.5% (25/40), χ²=11.429, P<0.01) before and 6 months after immunization were significantly different. Of the 421 doses of immunization, 25 (5.9%) doses reported controlled systemic or local adverse event. Conclusions: The immunization of pediatric patients with hematological and oncological diseases is of great importance. The newly-developed multidisciplinary cooperation immunization model for Chinese children with hematological and oncological diseases is feasible, and the immunization protocol is safe and has a certain effect.

Unprecedented Application of Covalent Organic Frameworks for Polymerization Catalysis: Rh/TPB-DMTP-COF in Polymerization of Phenylacetylene and Its Functional Derivatives

Covalent organic frameworks (COFs) are applied widely in organic catalysis; however, no precedent has been reported in polymerization catalysis. Herein, we report the new application of COFs for polymerization catalysis. Different amounts of homogeneous Rh catalyst are incorporated into the COF via post-treatment to give a series of TPB-DMTP-COF-X wt % Rh (b-e) containing varying amounts of Rh from 2.74 to 11.38 wt %. In contrast to the known Rh catalysts, TPB-DMTP-COF-X wt % Rh (b-e) display an uncommon synergistic effect and exceptional steric confinement effect of nanochannels. Therefore, they possess the advantages of both homogeneous catalysts in high activity and selectivity and heterogeneous catalysts in stability and recyclability with extremely high activity up to 1.3 × 10⁷ g·mol_Rh^-1·h^-1 and cis-selectivity up to 99% and can be readily recycled and reused five times in the polymerization of phenylacetylene and its derivatives, affording cis-transoidal polyphenylacetylene and its derivatives having helical structures, aggregation-induced emission properties, or fluorescence properties with narrow molecular weight distributions.

Cytomegalovirus-Specific Immunity Recovers More Slowly after Cord Blood Transplantation Compared with Matched Sibling Donor Allogeneic Transplantation

BACKGROUND

Rapid quantitative recovery of NK cells but slower recovery of T-cell subsets along with frequent viral infections are reported after umbilical cord blood (UCB) compared with matched sibling donor (MSD) hematopoietic cell transplantation (HCT). However, it remains unclear whether increased propensity for viral infections is also a result of slower recovery of virus-specific immunity after UCB as compared to MSD HCT.

OBJECTIVES

We examined the differences in the function of virus-specific peripheral blood mononuclear cells (PBMC) after UCB (N=17) vs. MSD (N=9) using previously collected patient blood samples at various time points after HCT.

METHODS

Interferon-gamma (IFN-γ) enzyme-linked immune absorbent spot (ELISpot) assay was used to quantify the PBMC frequencies that secrete IFN-γ in response to 11 immunopeptides from 5 common viruses. We included the patients who received the same reduced intensity conditioning regimen without ATG, no systemic glucocorticoids and had no relapse or acute/chronic graft-versus-host disease within 1 year after HCT.

RESULTS

The CMV-reactive PBMC frequencies were higher in CMV seropositive vs. seronegative patients after HCT. Among CMV seropositive patients, the frequency of CMV-reactive PBMC was lower after UCB compared to MSD throughout one year of HCT. We observed no differences in virus-specific PBMC responses towards HHV6, EBV, BK, and adenovirus antigens between UCB and MSD.

CONCLUSION

Our data demonstrate that the reconstitution of CMV-specific immunity is slower in CMV seropositive recipients of UCB vs. MSD HCT in contrast to other viruses which had similar recoveries. These study findings support implementation of more potent prophylactic strategies for preventing CMV reactivation in CMV seropositive patients receiving UCB HCT.

Effects of Expanded Graphite, Aluminum Hydroxide, and Kaolin on Flame Retardancy and Smoke Suppression of Polyurethane Composites

Polyurethane is a widely used polymer that has good abrasion resistance and low-temperature resistance. However, polyurethane composite materials are highly inflammable and thus require the use of flame retardants. This study selected green and environment-friendly flame retardants such as expanded graphite, aluminum hydroxide, and kaolin to be used as individual or paired retardants to produce polyurethane composites. By analyzing the potential and mechanical properties of the polyurethane composites, it was found that the composite material with the flame retardant composed of graphite and modified kaolin had better flame retardancy, smoke suppression performance, and high thermal stability.

[Efficacy and safety of hepatitis B re-vaccination in children after completion of chemotherapy and(or) hematopoietic stem cell transplantation]

Objective: To assess the anti-hepatitis B surface antibody (HBsAb) titers in children after completion of chemotherapy and (or) hematopoietic stem cell transplantation (HSCT), evaluate the efficacy and safety of the current hepatitis B re-vaccination schedule. Methods: A total of 239 children who completed their chemotherapy and (or) HSCT and visited the vaccination clinic of Shanghai Children's Medical Center from March 2017 to July 2019 were enrolled in this study. According to the previous diseases, patients were divided into leukemia group (85 cases), lymphoma group (30 cases), solid tumor group (49 cases) and non-malignant hematological disease group (75 cases). According to the treatment of previous diseases, the patients were divided into chemotherapy group (126 cases), HSCT group (89 cases) and chemotherapy plus HSCT group (24 cases). HBsAb titers were assessed both at the time of diagnosis and after completion of treatment and some children who were HBsAb seronegative were re-vaccinated with 3 doses of hepatitis B vaccine, the vaccine-related adverse reactions were monitored. HBsAb titers were measured again one month after the completion of inoculation. HBsAb titers were defined as negative at levels <10 U/L and positive at ≥ 10 U/L. Chi-square test or Fisher exact test was used to compare the difference of negative conversion rate of hepatitis B antibody between groups, and Logistic regression was used to explore the risk factors of hepatitis B antibody negative conversion. Results: Among 239 patients, there were 143 males and 96 females. At the time of diagnosis, 179 patients (74.9%) were HBsAb seropositive and 60 patients (25.1%) were HBsAb seronegative. After completion of chemotherapy and (or) HSCT, 133 of 179 children with HBsAb seropositive (74.3%) at diagnosis became HBsAb seronegative. Univariate analysis showed significant differences at the negative conversion rates of HBsAb between different disease groups (χ²=10.211，P=0.015), different treatments groups (χ²=14.899，P<0.01) and different HBsAb titers groups before treatment (χ²=32.117，P<0.01). Logistic regression showed that HSCT (chemotherapy group as the reference, odds ratio (OR）=2.999, 95% confidence interval (CI) 1.276-7.050，P=0.012) and HBsAb titers<328.2 U/L before treatment (HBsAb titers≥328.2 U/L group as the reference, OR=6.397， 95% CI3.159-12.954，P<0.01) were risk factors for negative conversion of HBsAb. Among 48 patients whose HBsAb was seronegative after completion of chemotherapy and (or) HSCT and re-vaccinated with hepatitis B vaccine, 47 (97.9%) cases became HBsAb seropositivie. No serious adverse effects or complications were reported among these patients. Conclusions: After completion of chemotherapy and (or) HSCT, most children completely lose their protective humoral immunity against hepatitis B. Hepatitis B re-vaccination schedule can be efficiently and safely applied in those patients.

2D shear wave elastography combined with age and serum biomarkers prior to kasai surgery predicts native liver survival of biliary atresia infants

BACKGROUND

The prognosis of patients with biliary atresia (BA) after Kasai portoenterostomy (KPE) varies, and precisely predicting the outcomes of KPE before surgery is still challenging.

METHODS

A total of 158 patients who underwent KPE in our hospital were included in this study. The patients in the training cohort were recruited from January 2012 to October 2017 (n = 118), and then, those in the validation cohort were recruited from November 2017 to April 2019 (n = 40). Combined nomogram models were developed based on two-dimensional shear wave elastography (2D SWE) values and other biomarkers. The utility of the proposed models was evaluated by C-index.

RESULTS

2D SWE played a potentially important role in predicting native liver survival (NLS) of BA patients with a C-index of 0.69 (0.63 to 0.75) in the training cohort and 0.76 (0.67 to 0.85) in the validation cohort. The nomogram A based on 2D SWE values, age, gamma-glutamyl transferase (GGT) and aspartate aminotransferase-to-platelet ratio (APRI) had a better C-index in the training cohort [0.74 (0.68-0.80) vs. 0.66 (0.60-0.73), P = 0.017] and in the validation cohort [0.78 (0.70-0.86) vs. 0.60 (0.49-0.71), P = 0.002] than the nomogram B (without 2D SWE). Using risk score developed from nomogram A, we successfully predicted 88.0% (22/25) of patients in the training cohort and 75.0% (9/12) in the validation cohort to have survival time of less than 12 months after KPE.

CONCLUSION

The combined nomogram model based on 2D SWE values, age, GGT and APRI prior to KPE can effectively predict NLS in BA infants.