Transmissibility of severe acute respiratory syndrome coronavirus 2 among household contacts of coronavirus disease 2019-positive patients: A community-based study in India.

BACKGROUND: This study identified the risk factors for severe acute respiratory syndrome coronavirus 2 infection among household contacts of index patients and determined the incubation period (IP), serial interval, and estimates of secondary infection rate in Kerala, India. METHODS: We conducted a cohort study in three districts of Kerala among the inhabitants of households of reverse transcriptase polymerase chain reaction-positive coronavirus disease 2019 patients between January and July 2021. About 147 index patients and 362 household contacts were followed up for 28 days to determine reverse transcriptase polymerase chain reaction positivity and the presence of total antibodies against SARS-CoV-2 on days 1, 7, 14, and 28. RESULTS: The mean IP, serial interval, and generation time were 1.6, 3, and 3.9 days, respectively. The secondary infection rate at 14 days was 43.0%. According to multivariable regression analysis persons who worked outside the home were protected (adjusted odds ratio [aOR], 0.45; 95% confidence interval [CI], 0.24-0.85), whereas those who had kissed the coronavirus disease 2019-positive patients during illness were more than twice at risk of infection (aOR, 2.23; 95% CI, 1.01-5.2) than those who had not kissed the patients. Sharing a toilet with the index patient increased the risk by more than twice (aOR, 2.5; 95% CI, 1.42-4.64) than not sharing a toilet. However, the contacts who reported using masks (aOR, 2.5; 95% CI, 1.4-4.4) were at a higher risk of infection in household settings. CONCLUSIONS: Household settings have a high secondary infection rate and the changing transmissibility dynamics such as IP, serial interval should be considered in the prevention and control of SARS-CoV-2.

Cytochrome P450 2C19 Polymorphisms and Its Association With Major Adverse Cardiac Events in Post-coronary Intervention Patients on Clopidogrel in the Tertiary Care Center.

Background Clopidogrel has become essential in managing coronary artery disease and other atherothrombotic diseases. It is an inactive prodrug that needs biotransformation in the liver by various cytochrome P (CYP) 450 isoenzymes for its active metabolite formation. However, 4-30% of patients on clopidogrel have shown no or decreased antiplatelet response. This condition is called 'clopidogrel non-responsiveness' or 'clopidogrel resistance.' This is attributed to genetic heterogeneity causing interindividual variation and increased risk of major adverse cardiac events (MACEs). This study aimed to assess MACEs and their association with CYP450 2C19 polymorphisms in post-coronary intervention patients on clopidogrel. Methods This prospective observational study was conducted on acute coronary syndrome patients, started on clopidogrel following coronary intervention. After considering inclusion and exclusion criteria, 72 patients were enrolled, and a genetic analysis was done. Based on genetic analysis, patients were divided into two groups, normal (CYP2C19*1) and abnormal phenotypes (CYP2C19*2 & *3). These patients were followed for two years, and the MACE during the first year and second year was compared between these two groups. Results Of 72 patients, 39 (54.1%) were normal, and 33 (45.8%) were abnormal genotypes. The mean age of patients is 67.71 ± 9.968. A total of 19 and 27 MACEs were seen during first- and second-year follow-ups. During the first-year follow-up, three (9.1%) patients with abnormal phenotypes developed ST-elevation myocardial infarction (STEMI), and none of the phenotypically normal patients developed STEMI (p-value = 0.183). Non-ST elevation myocardial infarction (NSTEMI) was seen in three (7.7%) normal and seven (21.2%) abnormal phenotype patients (p-value=0.19). Other events, such as thrombotic stroke, stent thrombosis, and cardiac death, were seen in two (6.1%) abnormal phenotypic patients (p-value=0.401). During the second-year follow-up, STEMI was seen in one (2.6%) normal and three (9.7%) abnormal phenotypic patients (p-value=0.183). NSTEMI was seen in four (10.3%) normal and nine (29%) abnormal phenotype patients (p=0.045). Comparison of total MACEs between normal and abnormal phenotypic groups at the end of the first year (p-value=0.011) and second year (p-value=<0.01) has statistical significance. Conclusion We can infer that the risk of developing a recurrent MACE in post-coronary intervention patients on clopidogrel is significantly high in the abnormal phenotypic group (CYP2C19*2 & *3) than in normal phenotypic patients.

Metabolic adaptation drives arsenic trioxide resistance in acute promyelocytic leukemia.

Acquired genetic mutations can confer resistance to arsenic trioxide (ATO) in the treatment of acute promyelocytic leukemia (APL). However, such resistance-conferring mutations are rare and do not explain most disease recurrence seen in the clinic. We have generated stable ATO-resistant promyelocytic cell lines that are less sensitive to all-trans retinoic acid (ATRA) and the combination of ATO and ATRA compared with the sensitive cell line. Characterization of these resistant cell lines that were generated in-house showed significant differences in immunophenotype, drug transporter expression, anti-apoptotic protein dependence, and promyelocytic leukemia-retinoic acid receptor alpha (PML-RARA) mutation. Gene expression profiling revealed prominent dysregulation of the cellular metabolic pathways in these ATO-resistant APL cell lines. Glycolytic inhibition by 2-deoxyglucose (2-DG) was sufficient and comparable to the standard of care (ATO) in targeting the sensitive APL cell line. 2-DG was also effective in the in vivo transplantable APL mouse model; however, it did not affect the ATO-resistant cell lines. In contrast, the resistant cell lines were significantly affected by compounds targeting mitochondrial respiration when combined with ATO, irrespective of the ATO resistance-conferring genetic mutations or the pattern of their anti-apoptotic protein dependency. Our data demonstrate that combining mitocans with ATO can overcome ATO resistance. We also show that this combination has potential for treating non-M3 acute myeloid leukemia (AML) and relapsed APL. The translation of this approach in the clinic needs to be explored further.

Universal screening for SARS-CoV-2 in pregnant women using a combination of antigen and RT-PCR testing.

Not available.

Management of relapse in acute promyelocytic leukaemia treated with up-front arsenic trioxide-based regimens.

The standard of care for patients with acute promyelocytic leukaemia (APL) relapsing after front-line treatment with arsenic trioxide (ATO)-based regimens remains to be defined. A total of 67 patients who relapsed after receiving ATO-based up-front therapy and were also salvaged using an ATO-based regimen were evaluated. The median (range) age of patients was 28 (4-54) years. While 63/67 (94%) achieved a second molecular remission (MR) after salvage therapy, three (4·5%) died during salvage therapy. An autologous stem cell transplant (auto-SCT) was offered to all patients who achieved MR, 35/63 (55·6%) opted for auto-SCT the rest were administered an ATO + all-trans retinoic acid maintenance regimen. The mean (SD) 5-year Kaplan-Meier estimate of overall survival and event-free survival of those who received auto-SCT versus those who did not was 90·3 (5·3)% versus 58·6 (10·4)% (P = 0·004), and 87·1 (6·0)% versus 47·7 (10·3)% (P = 0·001) respectively. On multivariate analysis, failure to consolidate MR with an auto-SCT was associated with a significantly increased risk of relapse [hazard ratio (HR) 4·91, 95% confidence interval (CI) 1·56-15·41; P = 0·006]. MR induction with ATO-based regimens followed by an auto-SCT in children and young adults with relapsed APL who were treated with front-line ATO-based regimens was associated with excellent long-term survival.

A phase II study evaluating the role of bortezomib in the management of relapsed acute promyelocytic leukemia treated upfront with arsenic trioxide.

The standard-of-care for patients with acute promyelocytic leukemia (APL) relapsing after upfront arsenic trioxide (ATO) therapy is not defined. The present study was undertaken to evaluate the safety of addition of bortezomib to ATO in the treatment of relapsed APL based on our previously reported preclinical data demonstrating synergy between these agents. This was an open label, nonrandomized, phase II, single-center study. We enrolled 22 consecutive patients with relapsed APL. The median age was 26.5 years (interquartile range 17.5 to 41.5). The median time from initial diagnosis to relapse was 23.1 months (interquartile range 15.6 to 43.8). All patients achieved hematological remission at a median time of 45 days (range 40-63). Nineteen patients were in molecular remission at the end of induction. Grade 3 adverse events occurred in eight instances with one patient requiring discontinuation of therapy for grade 3 neuropathy. Twelve (54.5%) patients underwent autologous transplantation (auto-SCT) in molecular remission while the rest opted for maintenance therapy. The median follow-up was 48 months (range 28-56.3). Of the patients undergoing auto-SCT, all except one was alive and relapse free at last follow-up. Of the patients who opted for maintenance therapy, three developed a second relapse. For treatment of APL relapsing after upfront ATO therapy, addition of bortezomib to a standard ATO-based salvage regimen is safe and effective. This trial was registered at www.clinicaltrials.gov as NCT01950611.

Combination Lenalidomide/Bortezomib Treatment Synergistically Induces Calpain-Dependent Ikaros Cleavage and Apoptosis in Myeloma Cells.

Multiple myeloma had been successfully treated by combining lenalidomide and bortezomib with reports suggesting benefits of such a combination even in relapsed/refractory cases. Recently, it was demonstrated that Ikaros degradation by lenalidomide happens via proteasome-dependent pathway and this process is critical for the eradication of myeloma cells. On the basis of this, an antagonistic effect should be observed if a combination of both these agents were used, which however is not the observation seen in the clinical setting. Our study demonstrates that when these agents are combined they exhibit a synergistic activity against myeloma cells and degradation of Ikaros happens by a proteasome-independent calcium-induced calpain pathway. Our study identifies the crucial role of calcium-induced calpain pathway in inducing apoptosis of myeloma cells when this combination or lenalidomide and bortezomib is used. We also report that this combination enhanced the expression of CD38 compared with lenalidomide alone. Thus, data from our study would establish the rationale for the addition of daratumumab along with this combination to further enhance therapeutic activity against multiple myeloma. IMPLICATIONS: Lenalidomide and bortezomib combination degrades IKZF1 in multiple myeloma through a calcium-dependent calpain and caspase pathway. VISUAL OVERVIEW: http://mcr.aacrjournals.org/content/molcanres/18/4/529/F1.large.jpg.

Stromal cells downregulate miR-23a-5p to activate protective autophagy in acute myeloid leukemia.

Complex molecular cross talk between stromal cells and the leukemic cells in bone marrow is known to contribute significantly towards drug-resistance. Here, we have identified the molecular events that lead to stromal cells mediated therapy-resistance in acute myeloid leukemia (AML). Our work demonstrates that stromal cells downregulate miR-23a-5p levels in leukemic cells to protect them from the chemotherapy induced apoptosis. Downregulation of miR-23a-5p in leukemic cells leads to upregulation of protective autophagy by targeting TLR2 expression. Further, autophagy inhibitors when used as adjuvants along with conventional drugs can improve drug sensitivity in vitro as well in vivo in a mouse model of leukemia. Our work also demonstrates that this mechanism of bone marrow stromal cell mediated regulation of miR-23a-5p levels and subsequent molecular events are relevant predominantly in myeloid leukemia. Our results illustrate the critical and dynamic role of the bone marrow microenvironment in modulating miRNA expression in leukemic cells which could contribute significantly to drug resistance and subsequent relapse, possibly through persistence of minimal residual disease in this environment.

Evaluation of nonneutralizing antibodies against factor VIII in severe haemophilia A patients from India.

: Haemophilia A is treated by replacement therapy with factor VIII (FVIII) concentrate. This strategy of treatment is ineffective in some patients due to the development of neutralizing antibodies (NNAs) against FVIII. The inhibitors have been identified to act against the functional domains of FVIII. The presence of NNAs against FVIII has also been identified. There is limited data on the prevalence and significance of NNA in haemophilia. To identify the presence of NNA in severe haemophilia A in our population, patients who were recruited from community-based camps were evaluated for FVIII activity. The patient's samples were further analysed for inhibitor activity with Nijmegen-Bethesda Assay and for NNAs using an in-house ELISA. 312 severe haemophilia patients were analysed for inhibitors and NNA. In-house ELISA picked up antibodies in 56 patients (17.9%). Of these 42 (13.7%) had inhibitory antibodies and in 14 patients (4.5%) there was no evidence of FVIII inhibitory activity. A substantial number of patients with severe haemophilia A have NNA. Continuous long-term follow-up is required in this cohort to evaluate the significance of this observation.

Prevalence of FVIII inhibitors in severe haemophilia A patients: Effect of treatment and genetic factors in an Indian population.

INTRODUCTION: Factor replacement therapy in treatment of haemophilia A is complicated by the production of neutralising antibodies known as inhibitors. The formation of inhibitors is multifactorial being associated with both genetic and environmental factors. AIM: To document the prevalence of inhibitors in severe haemophilia in the community where most patients receive only infrequent episodic replacement therapy and evaluate the factors which could be contributing to it. METHODS: Community based camps were conducted in different parts of the country. Patients were assessed through a structured questionnaire and blood samples were obtained for laboratory evaluation of inhibitors and defined immunological parameters. RESULTS: Inhibitors were present in 87/447 (19.5%) of the evaluated patients. High-titre inhibitor (>5 Bethesda Units [BU]) was identified in 31 (35.6%) patients. HLA DRB1-13-positive cases (RR = 2.04; 95% CI 1.06-3.911; P = 0.033) had an increased risk of inhibitor formation which was retained in the high-titre subset. A decreased risk of inhibitor formation was noted with heterozygous IL4-590 C/T allele (RR = 0.22; 95% CI 0.108-0.442: P = 0.000). There were no significant correlations between any of the evaluated environmental factors and the development of inhibitors in this study. CONCLUSION: The overall prevalence of inhibitors in patients with severe haemophilia A is similar to that reported among patients receiving regular replacement therapy. The data from this study, limited by its retrospective and cross-sectional study design, would suggest that genetic rather than environmental are more likely to impact the development of inhibitors.

Arsenic Trioxide Enhances the NK Cell Cytotoxicity Against Acute Promyelocytic Leukemia While Simultaneously Inhibiting Its Bio-Genesis.

Natural killer cells (NK) contribute significantly to eradication of cancer cells, and there is increased interest in strategies to enhance it's efficacy. Therapeutic agents used in the treatment of cancer can impact the immune system in a quantitative and qualitative manner. In this study, we evaluated the impact of arsenic trioxide (ATO) used in the management of acute promyelocytic leukemia (APL) on NK cell reconstitution and function. In patients with APL treated with single agent ATO, there was a significant delay in the reconstitution of circulating NK cells to reach median normal levels from the time of diagnosis (655 days for NK cells vs 145 and 265 days for T cells and B cells, respectively). In vitro experiments demonstrated that ATO significantly reduced the CD34 hematopoietic stem cell (HSC) differentiation to NK cells. Additional experimental data demonstrate that CD34+ sorted cells when exposed to ATO lead to a significant decrease in the expression of IKZF2, ETS1, and TOX transcription factors involved in NK cell differentiation and maturation. In contrast, exposure of NK cells and leukemic cells to low doses of ATO modulates NK cell receptors and malignant cell ligand profile in a direction that enhances NK cell mediated cytolytic activity. We have demonstrated that NK cytolytic activity toward NB4 cell line when exposed to ATO was significantly higher when compared with controls. We also validated this beneficial effect in a mouse model of APL were the median survival with ATO alone and ATO + NK was 44 days (range: 33-46) vs 54 days (range: 52-75). In conclusion, ATO has a differential quantitative and qualitative effect on NK cell activity. This information can potentially be exploited in the management of leukemia.

Mechanisms and management of coagulopathy in acute promyelocytic leukemia.

Acute promyelocytic leukemia (APL) is a subtype of leukemia which is associated with unique and distinctive coagulopathy. In the absence of treatment it is rapidly fatal and even after initiation of therapy the major cause of early mortality is related to hemorrhagic complications. The coagulopathy can be exacerbated with the start of treatment. In the absence of early hemorrhage related deaths the probability of cure exceeds 90% in low and intermediate risk patients and 80% even in high risk patients, highlighting the importance of understanding the pathophysiology of this complication and instituting prompt and appropriate management strategies. The coagulopathy in APL is complex and results from a combination of thrombocytopenia, disseminated intravascular coagulation and hyperfibronlysis. Recently the effect of all-trans retinioc acid (ATRA) induced ETosis on exacerbating coagulopathy in the first few days after starting therapy with this agent raises the potential for potentially novel strategies to reduce the risk of hemorrhage. Currently management is mainly related to rapid initiation of therapy with ATRA along with appropriate and adequate replacement of blood products to correct the coagulopathy. There is limited role for the use of low dose anti-coagulants and anti-fibrinolytic agents in the initial management of this disease. There is limited data on the use of rFVIIa or the use of global tests of hemostasis in the management of this condition.

Retraction: Association Between 5-HTR2C -759C/T (rs3813929) and -697G/C (rs518147) Gene Polymorphisms and Risperidone-Induced Insulin Resistance Syndrome in an Indian Population.

The above article from the Journal of Clinical Pharmacology, first published online on 22 September 2017 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement among the authors, the journal Editor in Chief, Joseph Bertino, and Wiley Periodicals, Inc. The retraction has been agreed upon due to the article having been submitted by the lead author without agreement from all co-authors. Having been alerted to this irregularity, the journal was also advised by the Senior Author of inaccuracies in the genotyping data. Reference Das, S., Dey, J. K., Prabhu SS, N., David, S., Kumar, A., Braganza, D. and Shanthi FX, M. (2017), Association Between 5-HTR2C -759C/T (rs3813929) and -697G/C (rs518147) Gene Polymorphisms and Risperidone-Induced Insulin Resistance Syndrome in an Indian Population. The Journal of Clinical Pharmacology. doi:10.1002/jcph.1012.

Diffuse large B cell lymphoma in wiskott-Aldrich syndrome: a case report and review of literature.

Wiskott-Aldrich syndrome (WAS) is an X linked rare primary immunodeficiency syndrome with an increased propensity for infection, autoimmunity and malignancy. Here we report a male child, who was diagnosed with WAS at 1 year of age following evaluation for symptomatic thrombocytopenia and eczematous skin lesions. He presented later with lymphadenopathy, which was consistent with diffuse large B cell lymphoma on histopathology. He received 6 cycles of R-CHOP chemotherapy for the same and is presently in remission after 6 months. We review the major publications of lymphoma in WAS and discuss the pathological findings, treatment and prognosis of lymphoma in WAS.

Activation of the cellular unfolded protein response by recombinant adeno-associated virus vectors.

The unfolded protein response (UPR) is a stress-induced cyto-protective mechanism elicited towards an influx of large amount of proteins in the endoplasmic reticulum (ER). In the present study, we evaluated if AAV manipulates the UPR pathways during its infection. We first examined the role of the three major UPR axes, namely, endoribonuclease inositol-requiring enzyme-1 (IRE1α), activating transcription factor 6 (ATF6) and PKR-like ER kinase (PERK) in AAV infected cells. Total RNA from mock or AAV infected HeLa cells were used to determine the levels of 8 different ER-stress responsive transcripts from these pathways. We observed a significant up-regulation of IRE1α (up to 11 fold) and PERK (up to 8 fold) genes 12-48 hours after infection with self-complementary (sc)AAV2 but less prominent with single-stranded (ss)AAV2 vectors. Further studies demonstrated that scAAV1 and scAAV6 also induce cellular UPR in vitro, with AAV1 vectors activating the PERK pathway (3 fold) while AAV6 vectors induced a significant increase on all the three major UPR pathways [6-16 fold]. These data suggest that the type and strength of UPR activation is dependent on the viral capsid. We then examined if transient inhibition of UPR pathways by RNA interference has an effect on AAV transduction. siRNA mediated silencing of PERK and IRE1α had a modest effect on AAV2 and AAV6 mediated gene expression (∼1.5-2 fold) in vitro. Furthermore, hepatic gene transfer of scAAV2 vectors in vivo, strongly elevated IRE1α and PERK pathways (2 and 3.5 fold, respectively). However, when animals were pre-treated with a pharmacological UPR inhibitor (metformin) during scAAV2 gene transfer, the UPR signalling and its subsequent inflammatory response was attenuated concomitant to a modest 2.8 fold increase in transgene expression. Collectively, these data suggest that AAV vectors activate the cellular UPR pathways and their selective inhibition may be beneficial during AAV mediated gene transfer.

Management of hemophilia in patients with inhibitors: the perspective from developing countries.

Data are limited on inhibitors in people with hemophilia (PWH) in developing countries. There is a perception that the overall prevalence of inhibitors, ranging from 7 to 19% in different reports, may be lower in these countries as compared with that reported from developed countries. This is possible given the fact that most patients are treated after 2 years of age with plasma-derived clotting factor concentrates. Whether genetic or other environmental factors also contribute to this needs further evaluation. There is a need to develop laboratory infrastructure and establish quality control programs for laboratory tests for inhibitors in developing countries. Management options vary widely given the socioeconomic diversity among these countries. Significant individualization of approach to management is therefore required depending on the available resources, particularly with regard to the use of bypassing agents. The limited data on immune tolerance induction with some low-dose regimens deserve further evaluation. Even in resource-constrained environments, education and a policy of systematic screening of patients associated with judicious use of bypassing agents can significantly improve the care of PWH who develop inhibitors.