Structural and mechanistic basis of anti-termination of Rho-dependent transcription termination by bacteriophage P4 capsid protein Psu

The conserved bacterial transcription terminator, Rho, is a potent target for bactericidal agents. Psu, a bacteriophage P4 capsid protein, is capable of inducing anti-termination to the Rho-dependent transcription termination. Knowledge of structural and mechanistic basis of this anti-termination is required to design peptide-inhibitor(s) of Rho from Psu. Using suppressor genetics, cross-linking, protein foot-printing and FRET analyses, we describe a conserved disordered structure, encompassing 139–153 amino acids of Rho, as the primary docking site for Psu. Also a neighbouring helical structure, comprising 347–354 amino acids, lining its central channel, plays a supportive role in the Rho–Psu complex formation. Based on the crystal structure of Psu, its conformation in the capsid of the P4 phage, and its interacting regions on Rho, we build an energy-minimized structural model of the Rho:Psu complex. In this model, a V-shaped dimer of Psu interacts with the two diagonally opposite subunits of a hexameric Rho, enabling Psu to form a ‘lid’ on the central channel of the latter. We show that this configuration of Psu makes the central channel of Rho inaccessible, and it causes a mechanical impediment to its translocase activity

Tidal Forces in Kerr-AdS and Grey Galaxies

In a recent paper [arXiv:2305.08922], it has been proposed that the endpoint of the Kerr-AdS superradiant instability is a Grey Galaxy. The conjectured solutions are supposed to be made up of a black hole with critical angular velocity in the centre of AdS, surrounded by a large flat disk of thermal bulk gas that revolves around the black hole. In the analysis of the proposed solutions so far, gravitational effects due to the black hole on the thermal gas have been neglected. A way to estimate these effects is via computing tidal forces. With this motivation, we study tidal forces on objects moving in the Kerr-AdS spacetime. To do so, we construct a parallel-transported orthonormal frame along an arbitrary timelike or null geodesic. We then specialise to the class of fast rotating geodesics lying in the equatorial plane, and estimate tidal forces on the gas in the Grey Galaxies, modelling it as a collection of particles moving on timelike geodesics. We show that the tidal forces are small (and remain small even in the large mass limit), thereby providing additional support to the idea that the gas is weakly interacting with the black hole.Comment: 24 pages, 2 figure

DYNAMIC STACK PORT SERDES POWER UTILIZATION FOR A SUSTAINABLE DATA STACK

Multiple network switches may be stacked, one atop another, and then interconnected through each switch’s two stack ports (SPs). Within such a stack arrangement, techniques are presented herein that support dynamically reducing the power utilization of a switch’s SP Serializer/Deserializer (SerDes) blocks without interrupting any data traffic. Under aspects of the presented techniques, a switch may transition between different power saving modes, which may include a normal mode (encompassing powering down the SerDes blocks of both of the switch’s SPs), an optimized mode (encompassing reducing the speed of the SP SerDes blocks), and a smart mode (encompassing dynamically powering up and down one of the switch’s SPs based on a budgeting of the network traffic). Under further aspects of the presented techniques, the selection of a power saving mode may be based on a switch’s configuration (such as a standalone arrangement, part of a half-ring topology, or part of a full-ring topology) and a switch’s input traffic bandwidth

Study of compliance and impact of infant and young child feeding counseling in Patna district, Bihar

Background: The infant and young child feeding (IYCF) practices have crucial role for physical and mental development of the child. Objective: To study the compliance to IYCF practices and impact of IYCF counseling in and around Patna district. Methods: Cross-sectional study was done in a hospital-based survey to find out compliance, and impact of IYCF practice counseling among infants and children attending a tertiary level hospital, Patna. Children in the age group, 6-24 months in and around Patna, were studied. Results: About 24% of the mothers initiated breastfeeding within an hour after birth. Exclusive breastfeeding for 6 months was practiced only by 36% of the mothers. Nearly, 43% of the mothers started complementary feeding at 6 months, and 45% of the infants were breastfed for 2 years. In the present study, 26% of mothers were using as age-appropriate complementary feeding and 35% of the mothers were feeding actively their child both during and after illness. Conclusion: Despite 3 years of counseling, compliance to IYCF practice in our area is low, and thus, the impact of IYCF counseling is poor in our area. Low knowledge score of mothers, lesser number of antenatal care visit is found to be an important factor responsible for low compliance

The first structure of polarity suppression protein, Psu from enterobacteria phage P4, reveals a novel fold and a knotted dimer

Psu is a capsid decoration protein of bacteriophage P4 and acts as an antiterminator of Rho-dependent transcription termination in bacteria. So far, no structures have been reported for the Psu protein or its homologues. Here, we report the first structure of Psu solved by the Hg2+ single wavelength anomalous dispersion method, which reveals that Psu exists as a knotted homodimer and is first of its kind in nature. Each monomer of Psu attains a novel fold around a tight coiled-coil motif. CD spectroscopy and the structure of an engineered disulfide-bridged Psu derivative reveal that the protein folds reversibly and reassembles by itself into the knotted dimeric conformation without the requirement of any chaperone. This structure would help to explain the functional properties of the protein and can be used as a template to design a minimal peptide fragment that can be used as a drug against Rho-dependent transcription termination in bacteria

Direct actions of adiponectin on changes in reproductive, metabolic, and anti-oxidative enzymes status in the testis of adult mice

Accepted manuscriptObesity is a major health problem that is linked to decreased sperm count. It is hypothesized that an obesity-associated reduction in adiponectin secretion may be responsible for impairment of spermatogenesis. Therefore, the aim of the study was to evaluate the direct role of adiponectin in spermatogenesis and steroid synthesis in adult mice. This study showed that adiponectin receptors (AdipoR1 and AdipoR2) were localized in Leydig cells and seminiferous tubules in the testis of adult mice. The result of the in vitro study showed the direct action of adiponectin on spermatogenesis by stimulating cell proliferation (PCNA) and survival (Bcl2) and by suppressing cell apoptosis. Treatment of testis with adiponectin also enhanced transport of the energetic substrates glucose and lactate to protect cells from undergoing apoptosis. Adiponectin treatment further showed a significant reduction in oxidative stress and nitric oxide. Our findings suggest that adiponectin effectively facilitates cell survival and proliferation, as well as protects from apoptosis. Thus, adiponectin treatment may be responsible for enhancing sperm counts. Interestingly, this study showed the stimulatory effect of adiponectin in spermatogenesis but showed an inhibitory effect on testosterone and estradiol synthesis in the testes. Based on the present study, it is hypothesized that systemic adiponectin treatment may be a promising therapeutic strategy for the improvement of spermatogenesis and sperm count.University Grants Commission, New-Delhi, India. The authors would like to thank DeAnn Hubberd and Madison Hedrick from the Science Communications Department at the University of Arkansas for Medical Sciences for their work editing this manuscript. This work was also supported by Centre of Advanced Study, Department of Zoology, Banaras Hindu University, Varanasi, Indiainfo:eu-repo/semantics/acceptedVersio

Students’ Choice and Motivation for Journalism Education in Indian Private Universities

The study of journalism and Students' choice for learning has hardly recognised in the age of technology and proliferation of media industries. India has witnessed unprecedented growth of private vocational journalism institutes, where Students' choice for learning in journalism education remains inadequate attention. The paper brings an attempt to explore the Students' choice for learning and their future aspirations. The empirical survey results indicate that aspirations of the diverse Students' communities in private institutions can not only be met through interdisciplinary approach and cultural specific pedagogies, but social inclusiveness in media education can bridge the gap between supply and demand in the media sector

Role of adiponectin as a modulator of testicular function during aging in mice

The mechanisms by which testicular functions decline with aging remain largely speculative. Our recent finding showed the importance of adiponectin in the regulation of testicular functions, whereas its concentration declines during male infertility. Thus, the aim of present study was to explore the potential role of adiponectin during aging. The changes in adiponectin, adiponectin-receptors, and insulin receptor proteins expression in the testis were evaluated and compared with the testicular parameters, mass, and testosterone level in the mice from early post-natal to late senescence period. Further, the current study has examined the effect of exogenous adiponectin treatment on testicular functions in aged mice. The results showed a significant decline in adiponectin/adiponectin-receptors expression simultaneously with a significant decline in testicular mass, insulin receptor expression and testosterone synthesis in the testis of aged mice. Exogenous treatment of adiponectin to aged mice resulted in marked improvements in testicular mass, histological features (cells proliferation), insulin receptor expression, testicular glucose uptake, anti-oxidative enzymes activity and testosterone synthesis as compared with the control. Based on these findings, it may be concluded that a marked decline in adiponectin synthesis and action results in decreased insulin sensitivity (development of insulin resistance) and increased oxidative stress which consequently suppresses testicular functions during aging. This study further showed that treatment with adiponectin ameliorates reduced testicular functions by enhanced expression of insulin receptor in the testis of senescent mice. It is thus hypothesized that systemic adiponectin treatment could be a promising therapeutic strategy for improvement of testosterone production and sperm counts during aging.Mayank Choubey greatly acknowledges financial assistance in the form of a Senior Research Fellowship (SRF) from Indian Council of Medical Research (ICMR File No. RBMH/FW/2018/1), New Delhi, India. This work was also supported by University Grant Commission (UGC), New Delhi and Centre of Advanced Study, Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi, India

Protein Profile of Human Lung Epithelial Cells (A549) Revealing Deviation in Cytoskeleton Proteins in Response to Zinc Oxide Nanoparticles Exposure

Zinc oxide nanoparticles (ZnO NPs) are widely used in biomedicine and scientific research because of their high dissolution property and bioavailability. On the contrary, this property also increases the intracellular reactivity, accessibility and cytotoxicity. These nano-bio interactions could induce undesirable changes in the proteome of the interacting cells, especially in the lung cells as these are the primary contact site. However, the potential effects of ZnO NPs exposure on proteome remain unclear. Proteomics data will substantiate the detailed mechanism of cellular interactions and modulatory effects of ZnO NPs on cells. Quantitative proteomic profiling was done using MALDI-TOF/TOF and MS/MS to identify differential protein expression on exposure to NPs among non exposed and exposed cells. Twenty-two proteins, with approximately 1.5 fold differential expression in cells exposed to ZnO NPs as compared to control cells were identified. Differentially expressed proteins were further classified using PANTHER software on the basis of functional gene ontology term: molecular function, biological process and cellular component. ToppGene suite was used to study protein-protein interaction and network was enriched with STRING. This study is a systematic analysis of protein modulation of the A549 cells exposed to ZnO NPs indicating alterations in the cytoskeleton

Prevalence, Response to Cysticidal Therapy, and Risk Factors for Persistent Seizure in Indian Children with Neurocysticercosis

Background. Neurocysticercosis (NCC) is the commonest cause of childhood acquired epilepsy in developing countries. The use of cysticidal therapy in NCC, except “single lesion NCC,” is still debated in view of its doubtful usefulness and potential adverse effects. Methods. Children presenting with first episode of seizure or acute focal neurological deficit without fever were screened for NCC and received appropriate therapy (followup done for 1 year to look for the response and side effects). Results. The prevalence of NCC was 4.5%. Most common presenting feature was generalized seizure and commonest imaging finding was single small enhancing lesion in the parietal lobe. Abnormal EEG and CSF abnormalities were found in almost half of the children. The response to therapy was very good with infrequent recurrence of seizure and adverse effects of therapy were encountered rarely. No risk factors for persistent seizure could be identified. Conclusion. Present study shows that the response to cysticidal therapy is very good in NCC as seizure recurrence was observed in only 5%, 4.2%, and 4.2% of cases at 3-month, 6-month, and 1-year followup. Adverse effects of therapy were observed in 20% of cases during therapy but they were mild and self-limiting