Fingolimod (FTY720), an FDA-approved sphingosine 1-phosphate (S1P) receptor agonist, restores endothelial hyperpermeability in cellular and animal models of dengue virus serotype 2 infection

Extensive vascular leakage and shock is a major cause of dengue-associated mortality. At present, there are no specific treatments available. Sphingolipid pathway is a key player in the endothelial barrier integrity; and is mediated through the five sphingosine-1-phosphate receptors (S1PR1-S1PR5). Signaling through S1PR2 promotes barrier disruption; and in Dengue virus (DENV)-infection, there is overexpression of this receptor. Fingolimod (FTY720) is a specific agonist that targets the remaining barrier-protective S1P receptors, without targeting S1PR2. In the present study, we explored whether FTY720 treatment can alleviate DENV-induced endothelial hyperpermeability. In functional assays, in both in vitro systems and in AG129 animal models, FTY720 treatment was found effective. Upon treatment, there was complete restoration of the monolayer integrity in DENV serotype 2-infected human microvascular endothelial cells (HMEC-1). At the molecular level, the treatment reversed activation of the S1P pathway. It significantly reduced the phosphorylation of the key molecules such as PTEN, RhoA, and VE-Cadherin; and also, the expression levels of S1PR2. In DENV2-infected AG129 mice treated with FTY720, there was significant improvement in weight gain, in overall clinical symptoms, and in survival. Whereas 100% of the DENV2-infected, untreated animals died by day-10 post-infection, 70% of the FTY720-treated animals were alive; and at the end of the 15-day post-infection observation period, 30% of them were still surviving. There was a significant reduction in the Evan's-blue dye permeability in the organs of FTY720-treated, DENV-2 infected animals; and also improvement in the hemogram, with complete restoration of thrombocytopenia and hepatic function. Our results show that the FDA-approved molecule Fingolimod (FTY720) is a promising therapeutic intervention in severe dengue.

Higher-temperature-adapted dengue virus serotype 2 strain exhibits enhanced virulence in AG129 mouse model

The factors that drive dengue virus (DENV) evolution, and selection of virulent variants are yet not clear. Higher environmental temperature shortens DENV extrinsic incubation period in mosquitoes, increases human transmission, and plays a critical role in outbreak dynamics. In the present study, we looked at the effect of temperature in altering the virus virulence. We found that DENV cultured at a higher temperature in C6/36 mosquito cells was significantly more virulent than the virus grown at a lower temperature. In a mouse model, the virulent strain induced enhanced viremia and aggressive disease with a short course, hemorrhage, severe vascular permeability, and death. Higher inflammatory cytokine response, thrombocytopenia, and severe histopathological changes in vital organs such as heart, liver, and kidney were hallmarks of the disease. Importantly, it required only a few passages for the virus to acquire a quasi-species population harboring virulence-imparting mutations. Whole genome comparison with a lower temperature passaged strain identified key genomic changes in the structural protein-coding regions as well as in the 3'UTR of the viral genome. Our results point out that virulence-enhancing genetic changes could occur in the dengue virus genome under enhanced growth temperature conditions in mosquito cells.

Impact of demographic profile on nutritional labelling usage by working women population of Varanasi, India

Nutritional labelling is the nutritional description of the food on the label to help the consumer in food selection. The present study aimed to assess the knowledge, attitude and practices adopted by the subjects and correlate them to have a better understanding of their nutritional background. Nutrition labels are a prominent first-glance article that needs to be very catchy and easy to interpret. The organizations responsible for formulating the rules and regulations must keep them updated and devise new formats of the display to enhance the usage of food labels up to the maximum possible level. A cross-sectional research study on 100 working women of Varanasi, aged between 20-50 years was conducted through a self-structured questionnaire to evaluate their KAP level. In view of the COVID-19 pandemic, the questionnaire was administered to the respondents through the online medium using Google forms. It can be inferred from the study that 58 % of the total respondents surveyed were aware of the labels, 61% of them had a positive attitude towards its usage but only 52% practised healthy shopping more often. About 70% of the participants preferred back-of-pack labelling rather than front-of-pack because the former provides elaborative information. The factors like qualification and occupation of women participants had negative associations with the satisfaction of the display format. The women having knowledge regarding traffic light labelling showed a positive association with the usefulness of the same. The average practice percentage adopted by the consumers had a negative association with factors like qualification, income, and occupation. The need for simplifying the display format and providing basic nutrition information to the population is highlighted in this study.

Berberine induces dose-dependent quiescence and apoptosis in A549 cancer cells by modulating cell cyclins and inflammation independent of mTOR pathway

AIM

Emerging studies have shown that application of low concentration of bioactive phytomolecules can confer anti-proliferative effects on tumour cells by inducing senescence pathways. The alkaloid berberine is recognized for its anti-cancer attributes but its potential to induce senescence in tumour cells is least understood.

MATERIALS AND METHODS

The present work assessed the mechanisms pertaining to dose-dependent anti-proliferative effects of berberine in the perspective of senescence and inflammation using human non-small cell lung cancer cell line (A549).

KEY FINDINGS

Amongst the different tested bioactive phytomolecules, berberine treatment suppressed the proliferation of A549 cells regardless of the concentration applied. Application of low doses of berberine induced a weak SA-β-gal activity and p21^WAF1 expression but did not show evidence of SASP activation due to absence of NF-κB activation and expression of proinflammatory genes. However, treatment with higher dose of berberine showed no evidence of SA-β-gal activity or p21^WAF1 expression, but instead induced apoptosis and suppressed the expression of cell cyclins. The proliferative capacity of berberine treated cells was at par with control cells and no SA-β-gal activity could be observed in first generation of berberine treated cells. mTOR pathway showed no distinct activation on account of berberine treatment thereby further emphasizing that low dose of berberine induced quiescence and not senescence in A549 cells.

SIGNIFICANCE

Taken together, our observations indicate that despite its strong anti-proliferative effects, low dose berberine treatment may only induce transient changes akin to quiescence that needs to be considered before implying pro-senescence attributes of berberine in cancer therapeutics.

Two-step hybrid calibration of remote microphones

A two-step, hybrid procedure to calibrate the remote microphones is presented. The calibration obtained in this manner can be directly applied to the measured pressure spectrum without resorting to any modeling or assumptions about the shape of the calibration curve. To demonstrate an application of the methodology, measurements of wall pressure fluctuations underneath a zero pressure gradient turbulent boundary layer were made. The calibrated pressure spectrum is shown to be qualitatively and quantitatively consistent with previous experimental studies and an empirical model, indicating the accuracy of the hybrid calibration technique.

Multifocal musculoskeletal tuberculosis in children: appearances on computed tomography

PURPOSE AND PATIENTS

The incidence of skeletal tuberculosis (TB), which once accounted for a majority of cases of extrapulmonary tuberculosis, has fallen significantly in recent years with the advent of effective drug therapy. Disseminated bone involvement in TB is very uncommon but it may still occur in countries where TB is endemic. We present the imaging findings of four children ranging in age from 2 to13 years, each of whom had multiple osseous stigmata of tuberculous infection. They presented to us over a period of 9 months.

RESULTS AND CONCLUSION

Three of four children had calvarial lesions, with involvement of the bony orbit in one, and large abscesses were present in the chest wall and the mediastinum of another. Lesions along the dorsal spine were demonstrated in three cases, two of which showed epidural extensions. Bone lesions in the thoracic cage accompanying those in the spine were also seen in two children, one of whom had a solitary destructive focus in a rib distant from the site of vertebral involvement. Bone lesions involving the first metacarpal in one case and the scapular wing in two others are also described. The diagnosis in each of the cases was confirmed by the identification of epitheloid giant cells and caseous necrosis or tubercle bacilli in fine needle aspirates or on tissue culture studies.

Fetus in fetu. Rare cause of a lump in an adult's abdomen

Fetus in fetu is a rare entity. The patient usually presents in childhood. A case in which the patient presented in adulthood, with a lump in the abdomen, is reported. Computed tomography findings were diagnostic of this condition and a prospective diagnosis could be made. Computed tomography also helped to differentiate it from mature teratoma.

Imaging findings in rabies encephalitis

SUMMARY

Rabies encephalitis is perhaps one of the few infectious diseases that command attention and fear not only from the layman but also from physicians. The unique mode of transmission, the virtually exclusive neurotransmission shown by the agent, and the complete hopelessness of the established disease sets rabies apart from other zoonoses transmitted to man. Rabies encephalitis is a fatal disease and its diagnosis is usually based on the clinical presentations and findings. Hence, imaging in rabies is seldom done, and imaging findings in rabies encephalitis have rarely been described. We present the imaging findings in two confirmed cases of rabies encephalitis in which antemortem diagnosis was obtained by corneal impression smears showing the presence of viral antigens. The differential diagnosis of the imaging findings as well as the role and the relevance of imaging in the diagnosis of this disease are discussed. The current literature on the subject is also reviewed.

Cerebral cryptococcosis: atypical appearances on CT

Cryptococcal infection is common in immunocompromised patients, often presenting with meningitis or meningoencephalitis. We report an unusual presentation of cryptococcal infection in an immunocompetent patient presenting with headache and hemiplegia. CT demonstrated a large ring-enhancing lesion in the parietal region with intralesional calcification.

Genetic heterogeneity in the Indian Mus musculus

This study deals with the characterization of 10 populations of M. musculus from different geographical locations in India. The genetics of Indian wild mice has been completely obscure and this is the first report on allozyme variations in the natural population. We have used a set of 24 biochemical genetic markers to measure levels of diversity within and among populations. The allelic frequency data indicate extreme genetic variability, which is further enhanced by the presence of novel alleles. Overall the species shows a high level of heterogeneity. The highly polymorphic central populations of M. musculus cannot be assigned to any one particular subspecies. The allelic profiles, however, indicate a gradual differentiation toward the castaneus and batcrianus subspecies lineages.

Metabolic changes induced by organophosphates in the piscine organs

Two common fish of commercial importance viz., Channa punctatus and Heteropneustes fossilis were exposed to sublethal concentrations of malathion and dimethoate (rogor). The exposure to malathion showed a gradual decrease in glycogen content in the liver and kidney of C. punctatus whereas the cholesterol level was increased. The protein content decreased initially, but thereafter a gradual increase was observed. However, in the exposure of H. fossilis to dimethoate, there was an increase in the glycogen content both in the liver and kidney during the second week. Thereafter a decrease was noted. The protein content showed insignificant changes. The specific activity of SDH showed a sharp rise initially for 2 weeks followed by a steep decline in both the tissues. The significance of these results are discussed in light of piscine metabolism.