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Background : The development of broad-range polymerase chain reaction (BR-PCR) and next-generation sequencing techniques has significant implications for antimicrobial stewardship by increasing clinicians' ability to provide a tailored antimicrobial regimen. We sought to explore the clinical utility of BR-PCR testing and its impact on antimicrobial treatment among an adult cohort in a large hospital system. Methods : We retrospectively evaluated samples that underwent BR-PCR testing between 2017 and 2021 and summarized their clinical characteristics and impact on antimicrobial therapy. We identified BR-PCR testing as having clinical utility if the results led to adjustment of antimicrobial choice or duration or to confirmation of the initial empiric regimen, while no clinical utility was assigned to results that were negative or clinically insignificant, unavailable due to loss to follow-up, or lacking clinical indication (treatment completed before the test results returned or conventional cultures revealed the causative pathogen). Results : Among 359 specimens, BR-PCR was positive for 107 (30%). Clinical utility was identified for 106 (29.5%) specimens, including 45 with negative BR-PCR results. The rates of clinical utility varied based on the type of sample tested, with the highest clinical utility associated with cranial samples (60%), followed by body fluid (56%) and endovascular (54%) samples, and the lowest with CSF (15%) and bone and joint (19%) samples. We also identified many BR-PCR tests that were not clinically indicated (23.4%). Conclusions : This study highlights the utility of BR-PCR testing to support antimicrobial stewardship initiatives. Further studies are needed to identify clinical scenarios in which it is appropriate to order BR-PCR testing and for a careful interpretation of negative BR-PCR results.

Cat scratch disease rarely presents as a breast or axillary mass mimicking carcinoma both clinically and radiologically. Diagnosing breast/axillary cat scratch disease is challenging due to its rarity and nonspecific findings. Here, we reported 2 patients with breast cat scratch disease and reviewed 14 patients with cat scratch disease involving breast/axilla from the past 30 years. It mainly affects women (median age: 48), consistently presenting as axillary lymphadenopathy, and demonstrates ipsilateral breast mass in half of patients (50%, 8/16). The breast mass was most commonly located in the upper outer quadrant (88%, 7/8), indicating the possibility of disease extension from axillary adenopathy. Around half of patients (56%, 9/16) reported cat exposure. Histologically, most patients (93%, 14/15) presented as necrotizing granulomas, with characteristic stellate-shaped necrosis in 5 patients. Although pathologic differential diagnoses between cat scratch disease and cancer are straightforward, distinguishing cat scratch disease from other granulomatous mastitis poses diagnostic challenges. Silver stains should be included in the diagnostic workup panel when highly suspecting cat scratch disease clinically. However, they were only able to highlight the causative microorganism in 54% (7/18) patients, and the gram stain was negative in all 12 tested patients. In contrast, polymerase chain reaction (PCR) for the causative microorganism was consistently positive in all 3 tested patients, while serologic test confirmed diagnosis in 85% (11/13) patients; 1 patient with negative serology showed a positive PCR result. Therefore, upfront PCR tests with or without serologic study should be considered to confirm the diagnosis of cat scratch disease in a timely manner., Competing Interests: Declaration of Conflicting InterestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Nocardiosis is a bacterial infection caused by organisms of the Nocardia genus. The disease typically involves the skin, central nervous system or pulmonary system. Very rarely nocardiosis can cause disease of other organs including bone and joints. Nocardiosis is typically a chronic, somewhat indolent infection, occurring in patients with defective cell mediated immunity. We describe a 78-year-old female with right shoulder septic arthritis resulting from Nocardia farcinica with associated involvement of her skin and lungs as well. She was treated with surgical debridement and combination antibiotic therapy. We also share a literature review of bone and joint infection caused by the N. farcinica species, highlighting its rarity. Understanding uncommon manifestations of nocardiosis allows for early recognition and treatment of the condition and optimal patient care., Competing Interests: None., (© 2022 The Authors.)

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a bat-derived betacoronavirus, that emerged around December 2019. In spite of the lesser genomic diversity of CoVs in general, a steady accumulation of mutations spread over its genome have been noted, resulting in the emergence of several clades and lineages. Majority of these mutations are random and non-functional changes; however a few variants of concern (VOC) and variants of interest (VOI) designated by the WHO since late 2020 have implications to diagnostics, pathogenicity and immune escape. This review discusses the various nomenclatures depicting the SARS-CoV-2 evolution, the designated VOCs and VOIs and the mutations characterizing these variants. The evolution of SARS-CoV-2 in India and the implications to vaccine efficacy and breakthrough infections is also addressed., (© 2022 Director General, Armed Forces Medical Services. Published by Elsevier, a division of RELX India Pvt. Ltd.)

Delhi, the national capital of India, experienced multiple severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreaks in 2020 and reached population seropositivity of >50% by 2021. During April 2021, the city became overwhelmed by COVID-19 cases and fatalities, as a new variant, B.1.617.2 (Delta), replaced B.1.1.7 (Alpha). A Bayesian model explains the growth advantage of Delta through a combination of increased transmissibility and reduced sensitivity to immune responses generated against earlier variants (median estimates: 1.5-fold greater transmissibility and 20% reduction in sensitivity). Seropositivity of an employee and family cohort increased from 42% to 87.5% between March and July 2021, with 27% reinfections, as judged by increased antibody concentration after a previous decline. The likely high transmissibility and partial evasion of immunity by the Delta variant contributed to an overwhelming surge in Delhi.

Purpose/objectives: Metastasis-directed therapy with stereotactic body radiotherapy (SBRT) in the setting of oligometastatic disease is a rapidly evolving paradigm given ongoing improvements in systemic therapies and diagnostic modalities. However, SBRT to targets in the abdomen and pelvis is historically associated with concerns about toxicity. The purpose of this study was to evaluate the safety and efficacy of SBRT to the abdomen and pelvis for women with oligometastases from primary gynecological tumors., Materials/methods: From our IRB-approved registry, all patients who were treated with SBRT between 2014 and 2020 were identified. Oligometastatic disease was defined as 1 to 5 discrete foci of clinical metastasis radiographically diagnosed by positron emission tomography (PET) and/or computerized tomography (CT) imaging. The primary endpoint was local control at 12 months. Local and distant control rates were estimated using the Kaplan-Meier method. Time intervals for development of local progression and distant progression were calculated based on follow up visits with re-staging imaging. Acute and late toxicity outcomes were determined based on Common Terminology Criteria for Adverse Events (CTCAE) version 5.0., Results: We identified 34 women with 43 treated lesions. Median age was 68 years (range 32-82), and median follow up time was 12 months (range 0.2-54.0). Most common primary tumor sites were ovarian (n=12), uterine (n=11), and cervical (n=7). Median number of previous lines of systemic therapy agents at time of SBRT was 2 (range 0-10). Overall, SBRT was delivered to 1 focus of oligometastasis in 29 cases, 2 foci in 2 cases, 3 foci in 2 cases, and 4 foci in 1 case. All patients were treated comprehensively with SBRT to all sites of oligometastasis. Median prescription dose was 24 Gy (range 18-54 Gy) in 3 fractions (range 3-6) to a median prescription isodose line of 83.5% (range 52-95). Local control by lesion at 12 and 24 months was 92.5% for both time points. Local failure was observed in three treated sites among two patients, two of which were at 11 months in one patient, and the other at 30 months. Systemic control rate was 60.2% at 12 months. Overall survival at 12 and 24 months was 85% and 70.2%, respectively. Acute grade 2 toxicities included nausea (n=3), and there were no grade > 3 acute toxicities. Late grade 1 toxicities included diarrhea (n=1) and fatigue (n=1), and there were no grade > 2 toxicities., Conclusion: SBRT to oligometastatic gynecologic malignancies in the abdomen and pelvis is feasible with encouraging preliminary safety and local control outcomes. This approach is associated with excellent local control and low rates of toxicity during our follow-up interval. Further investigations into technique, dose-escalation and utilization are warranted., Competing Interests: Authors’ disclosure of potential conflicts of interest The authors have nothing to disclose., (© 2021 Old City Publishing, Inc.)

Since the resurgence of chikungunya virus (CHIKV) in India in 2005, the Indian subcontinent sublineage of the Indian Ocean lineage (IOL) has continued transmission in India and also radiation from India causing additional outbreaks in surrounding countries. This study was undertaken for an in-depth understanding of the evolutionary dynamics of the IOL, the global transmission routes in the Indian context and possible association with mutational fitness. The whole genome sequencing of Indian isolates representing CHIKV outbreaks (2014-2018) from selected States of India was carried out, followed by phylogeography analysis of the IOL using the Bayesian Markov chain Monte Carlo method and selection pressure analysis. Phylogeography analysis of IOL strains revealed indigenous evolution in India at least at three time points, with specific mutations that conferred viral fitness in the Aedes vector species. Further dispersal of the strains from India was noted to neighbouring and distant countries with multiple exportations to Sri Lanka, Bangladesh and China. The study reveals India as an endemic reservoir for CHIKV and persistent global transmissions from India. Though natural selection does not appear to play a major role in establishment of the IOL, sustainable efforts towards vector control can help address the issues., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Studies conducted at neonatal intensive care units in Pune, western India, suggested early exposure to rotaviruses and predominance of unusual human-bovine-like G12P[11] strains. The whole genome sequencing and phylogenetic analyses of a naturally attenuated, culture adapted neonatal strain, (NIV-1740121) revealed multiple-gene reassortment events, containing ROTAVAC® vaccine strain, 116E-like VP4, VP6, NSP3, NSP5 genes, VP7 gene of G12 origin and VP3 gene of porcine ancestry in a human Wa-like backbone. Analysis of 3D structure modeling of the VP7 and VP4 proteins with respect to 116E suggested amino acid variations in the major neutralizing epitopes of VP7, contributed to a modified charge density. Visualization of receptor-glycan interaction structures of NIV-1740121 and 116E VP8* showed type I glycan binds with a similar conformation at the same active site as represented in the available crystal structure of G10P[11] VP8*. The study adds to the knowledge of age restricted tropism of P[11] strains in neonates., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The Kyasanur Forest Disease (KFD) has become a major public health problem in the State of Karnataka, India where the disease was first identified and in Tamil Nadu, Maharashtra, Kerala, and Goa covering the Western Ghats region of India. The incidence of positive cases and distribution of the Kyasanur Forest Disease virus (KFDV) in different geographical regions raises the need to understand the evolution and spatiotemporal transmission dynamics. Phylogeography analysis based on 48 whole genomes (46 from this study) and additionally 28 E-gene sequences of KFDV isolated from different regions spanning the period 1957-2017 was thus undertaken. The mean evolutionary rates based the E-gene was marginally higher than that based on the whole genomes. A subgroup of KFDV strains (2006-2017) differing from the early Karnataka strains (1957-1972) by ~2.76% in their whole genomes and representing spread to different geographical areas diverged around 1980. Dispersal from Karnataka to Goa and Maharashtra was indicated. Maharashtra represented a new source for transmission of KFDV since ~2013. Significant evidence of adaptive evolution at site 123 A/T located in the vicinity of the envelope protein dimer interface may have functional implications. The findings indicate the need to curtail the spread of KFDV by surveillance measures and improved vaccination strategies.

Background & Objectives: Since December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has globally affected 195 countries. In India, suspected cases were screened for SARS-CoV-2 as per the advisory of the Ministry of Health and Family Welfare. The objective of this study was to characterize SARS-CoV-2 sequences from three identified positive cases as on February 29, 2020., Methods: Throat swab/nasal swab specimens for a total of 881 suspected cases were screened by E gene and confirmed by RdRp (1), RdRp (2) and N gene real-time reverse transcription-polymerase chain reactions and next-generation sequencing. Phylogenetic analysis, molecular characterization and prediction of B- and T-cell epitopes for Indian SARS-CoV-2 sequences were undertaken., Results: Three cases with a travel history from Wuhan, China, were confirmed positive for SARS-CoV-2. Almost complete (29,851 nucleotides) genomes of case 1, case 3 and a fragmented genome for case 2 were obtained. The sequences of Indian SARS-CoV-2 though not identical showed high (~99.98%) identity with Wuhan seafood market pneumonia virus (accession number: NC 045512). Phylogenetic analysis showed that the Indian sequences belonged to different clusters. Predicted linear B-cell epitopes were found to be concentrated in the S1 domain of spike protein, and a conformational epitope was identified in the receptor-binding domain. The predicted T-cell epitopes showed broad human leucocyte antigen allele coverage of A and B supertypes predominant in the Indian population., Interpretation & Conclusions: The two SARS-CoV-2 sequences obtained from India represent two different introductions into the country. The genetic heterogeneity is as noted globally. The identified B- and T-cell epitopes may be considered suitable for future experiments towards the design of vaccines and diagnostics. Continuous monitoring and analysis of the sequences of new cases from India and the other affected countries would be vital to understand the genetic evolution and rates of substitution of the SARS-CoV-2., Competing Interests: None

The newly emerged 2019 novel coronavirus (CoV), named as severe acute respiratory syndrome CoV-2 (SARS-CoV-2), like SARS-CoV (now, SARS-CoV-1) and Middle East respiratory syndrome CoV (MERS-CoV), has been associated with high infection rates with over 36,405 deaths. In the absence of approved marketed drugs against coronaviruses, the treatment and management of this novel CoV disease (COVID-19) worldwide is a challenge. Drug repurposing that has emerged as an effective drug discovery approach from earlier approved drugs could reduce the time and cost compared to de novo drug discovery. Direct virus-targeted antiviral agents target specific nucleic acid or proteins of the virus while host-based antivirals target either the host innate immune responses or the cellular machineries that are crucial for viral infection. Both the approaches necessarily interfere with viral pathogenesis. Here we summarize the present status of both virus-based and host-based drug repurposing perspectives for coronaviruses in general and the SARS-CoV-2 in particular., Competing Interests: None

The number of whole-genome sequences of human rotavirus C (RVC) strains available in public databases is recently increasing. Thus far from India only a single whole genome of human RVC of a sporadic case was available. In this study, nearly full-length genome sequencing and phylogenetic analyses of three RVC strains isolated from three different gastroenteritis outbreaks during 2010-2014 in Western India was carried out. Further, an intra-genotypic lineage classification system for human RVCs based on the nucleotide divergence cut-off values was proposed by using the algorithm of the Rotavirus Classification Working Group. Two lineages could be defined for all the genes except the VP7 gene and the M3 VP3 genotype. Provisional classification of the lineages indicated the absence of reassortment events in the genomic constellation of Indian strains, contrary to earlier reports. The comparatively higher variability of the NSP1, NSP3, NSP5 and M2 VP3 genotype, emphasizes their utility in lineage classification.

The hemagglutinin (H) protein of measles viruses (MeV) mediates binding to the cellular receptors, CD46,human signaling lymphocyte activation molecule and nectin-4. Vaccine strains primarily contain H-proteins possessing MeV-H: Y481 and can utilize CD46. Reports suggest that a single amino acid change in MeV-H at position 481 in wild type strains renders them inefficient in utilizing CD46. The in-depth molecular mechanism by which substitutions at 481 and another reported critical residue position 546 affects CD46 binding affinity however remains elusive. We used molecular docking studies of CD46 with MeV-H possessing Y481 N/D to understand the in-depth molecular mechanism involved. It was found that loss in either of the hydrogen bond (H-bond) contacts (MeV-H:481-CD46:65, MeV-H:546-CD46:63) in the central contact region prevented efficient CD46 binding. Y481 N could form the specific H-bond, while G546S H-bond could be formed only in conjunction with Y481, revealing the significance of these residues in determining CD46 receptor binding potential. Elucidating the underlying molecular mechanism of receptor usage by the MeV has implications to understanding cellular tropism, viral pathogenesis and therapy., (Copyright © 2019. Published by Elsevier Ltd.)

Identification of amino-acid substitutions in the neuraminidase (NA) of low-pathogenic avian influenza (AI) H9N2 viruses is important to study the susceptibility to NA inhibitors (NAI). To identify mutations under NAI selective pressure, the virus was serially passaged with increasing levels of either oseltamivir or zanamivir in ovo, and the growth of the viruses in the presence and absence of NAI's compared. Mutations R292 K in the presence of oseltamivir and E119D in presence of zanamivir were observed within passage one and two respectively. The R292 K mutation reduced oseltamivir susceptibility significantly (2,523-fold) and moderately reduced susceptibility to zanamivir. The E119D mutation significantly reduced susceptibility to zanamivir (415-fold) and remained susceptible to oseltamivir. Genetic stability of the mutations assessed by serial passages of the mutant viruses in eggs without drug pressure resulted in the loss of these mutations, making the virus susceptible to both the drugs. Molecular modeling and dynamics simulations revealed that the R292 K mutation disrupted oseltamivir binding similar to other group 2 NAs, while a different mechanism was noted for zanamivir binding for both R292 K and E119D mutations. The study highlights the need for regular susceptibility screening of circulating AI viruses., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Measles viruses (MeV) circulating in India mainly belong to genoypes D4 and D8 of clade D. In the context of measles elimination goal 2020 in India, molecular clock and phylogeography studies would help to identify the timescales of evolution and track the transmission pathways of MeV. We used nucleoprotein gene sequences (n = 756) from GenBank, representing 86 countries (1973-2016), to study the spatiotemporal transmission dynamics of clade D. Genotype D4 was introduced into India around 1991 and genotype D8 around 1994. Recent transmissions of the D4 genotype of measles virus (MeV) were noted from India to the United States of America and East Asia region while D8 genotype importations from North America were noted in recent years., (Copyright © 2018. Published by Elsevier B.V.)

During 2015-2017, chikungunya virus (CHIKV) showed a resurgence in several parts of India with Karnataka, Maharashtra and New Delhi accounting for a majority of the cases. E2-E1 gene based characterization revealed Indian subcontinent sublineage strains possessing Aedes aegypti mosquito-adaptive mutations E1: K211E and E2:V264A, with the 211 site positively selected. Novel mutational sites E1: K16E/Q, E1: K132Q/T, E1: S355T, E2: C19R and E2:S185Y could be associated with epitopes or virulence determining domains. The study examines the role of host, vector and viral factors and fills gaps in our molecular epidemiology data for these regions which are known to possess a dynamic population.

An F35L mutation in the N-terminal domain of the polymerase acidic protein (PA-Nter), which contains the active site of the endonuclease, has been reported to result in higher polymerase activity in mouse-adapted strains of the 2009 pandemic influenza A H1N1 virus. We modeled wild and mutant complexes of uridine 5'-monophosphate (UMP) as the endonuclease substrate and performed molecular dynamics simulations. The results demonstrated that the F35L mutation could result in a changed orientation of a helix containing active site residues and improve the ligand affinity in the mutant strain. This study suggests a molecular mechanism of enhanced polymerase activity.

Chandipura virus (CHPV) is found to be associated with sporadic encephalitis outbreaks in humans in India since 1965. We report here, the investigation of CHPV activity during the period of June-August 2015 in the state of Gujarat, which revealed 24.44% positivity among 45 referred encephalitis cases. Phylogenetic study of the G gene sequences of strains from Gujarat 2015 along with available sequences of additional strains from different geographical locations and isolation years (1965-2015), indicated the relatedness of the 2015 strain to a group of the CHPV prototype strain of 1965 and the earliest outbreak strains of 2003. Analyses of selection pressure in the G gene revealed positively selected sites within the signal peptide region and a putative CHPV epitope. These results indicate a probable role of G protein-based immune selection and underline the need for continued surveillance to monitor genetic and antigenic variations in the CHPV., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Epidemiological findings suggest short sleep duration is associated with overweight and obesity across the lifespan. In adults, experimental sleep loss increases caloric intake more than total daily energy needs, thus leading to weight gain. To date, little is known about the relationship between sleep restriction and dietary intake in preschool children. Healthy children (n = 10; 41.2 ± 5.4 months; 5 females) followed a strict sleep schedule for 5 days before each experimental condition: 1 day of baseline sleep (nap and scheduled bedtime/wake time) and 1 day of sleep restriction (no-nap and ~2.3 h bedtime delay). Standardized parent-report dietary intake measures were obtained on baseline, sleep restriction and sleep recovery (ad libitum sleep opportunity in the 24-h following sleep restriction) days. As designed, children slept ~3 h less on the sleep restriction than the baseline day (P < 0.001), with no significant differences in sleep between baseline and recovery days (verified with actigraphy). Repeated-measures anovas indicated differences across conditions in total kilocalories, sugar, carbohydrate and fat intake (all P < 0.05; no differences in protein). Post hoc tests revealed that compared with baseline, children consumed 21% more kilocalories, 25% more sugar and 26% more carbohydrates on the day of sleep restriction, as well as 14% more kilocalories and 23% more fat on the day of sleep recovery (all P < 0.05). Findings suggest that acute sleep loss increases dietary intake in preschoolers both on the day of and the day after sleep restriction. Increased kilocalorie intake may promote weight gain over time and be a mechanism through which short sleep contributes to childhood obesity risk., (© 2016 European Sleep Research Society.)

Background: Because of the increasing complexities of providing imaging for pediatric health care services, a more reliable process to manage the daily delivery of care is necessary. Objective We describe our Daily Readiness Huddle and the effects of the process on problem identification and improvement., Materials and Methods: Our Daily Readiness Huddle has four elements: metrics review, clinical volume review, daily readiness assessment, and problem accountability. It is attended by radiologists, directors, managers, front-line staff with concerns, representatives from support services (information technology [IT] and biomedical engineering [biomed]), and representatives who join the meeting in a virtual format from off-site locations. Data are visually displayed on erasable whiteboards. The daily readiness assessment uses queues to determine whether anyone has concerns or outlier data in regard to S-MESA (Safety, Methods, Equipment, Supplies or Associates). Through this assessment, problems are identified and categorized as quick hits (will be resolved in 24-48 h, not requiring project management) and complex issues. Complex issues are assigned an owner, quality coach and report-back date. Additionally, projects are defined as improvements that are often strategic, are anticipated to take more than 60 days, and do not necessarily arise out of identified issues during the Daily Readiness Huddle. We tracked and calculated the mean, median and range of days to resolution and completion for complex issues and for projects during the first full year of implementing this process., Results: During the first 12 months, 91 complex issues were identified and resolved, 11 projects were in progress and 33 completed, with 23 other projects active or in planning. Time to resolution of complex issues (in days) was mean 37.5, median 34.0, and range 1-105. For projects, time to completion (in days) was mean 86.0, median 84.0, and range 5-280., Conclusion: The Daily Readiness Huddle process has given us a framework to rapidly identify issues, bring accountability to problem-solving, and foster improvement. It has also had a positive effect on team-building and coordination.

Avian influenza viruses of subtype H5N1 circulating in animals continue to pose threats to human health. The binding preference of the viral surface protein hemagglutinin (HA) to sialosaccharides of receptors is an important area for understanding mutations in the receptor binding site that could be the cause for avian-to-human transmission. In the present work, we studied the effect of two receptor binding site mutations, S221P singly and in combination with another mutation K216E in the HA protein of influenza A H5N1 viruses. Docking of sialic acid ligands corresponding to both avian and human receptors and molecular dynamics simulations of the complexes for wild and mutant strains of H5N1 viruses were carried out. The H5N1 strain possessing the S221P mutation indicated decreased binding to α2,3-linked sialic acids (avian receptor, SAα2,3Gal) when compared to the binding of the wild-type strain that did not possess the HA-221 mutation. The binding to α2,6-linked sialic acids (human receptor, SAα2,6Gal) was found to be comparable, indicating that the mutant strain shows limited dual receptor specificity. On the other hand, the S221P mutation in synergism with the K216E mutation in the binding site, resulted in increased binding affinity for SAα2,6Gal when compared to SAα2,3Gal, indicative of enhanced binding to human receptors. The in-depth study of the molecular interactions in the docked complexes could explain how co-occurring mutations in the HA viral protein can aid in providing fitness advantage to the virus, in the context of host receptor specificity in emerging variants of H5N1 influenza viruses.

The cap binding domain of the polymerase basic 2 (PB2) subunit of influenza polymerases plays a critical role in mediating the 'cap-snatching' mechanism by binding the 5' cap of host pre-mRNAs during viral mRNA transcription. Monitoring variations in the PB2 protein is thus vital for evaluating the pathogenic potential of the virus. Based on selection pressure analysis of PB2 gene sequences of the pandemic H1N1 (pH1N1) viruses of the period 2009-2014, we identified a site, 344V/M, in the vicinity of the cap binding pocket showing evidence of adaptive evolution and another co-evolving residue, 354I/L, in close vicinity. Modelling of the three-dimensional structure of the pH1N1 PB2 cap binding domain, docking of the pre-mRNA cap analogue m7GTP and molecular dynamics simulation studies of the docked complexes performed for four PB2 variants observed showed that the complex possessing V344M with I354L possessed better ligand binding affinity due to additional hydrogen bond contacts between m7GTP and the key residues His432 and Arg355 that was attributed to a displacement of the 424 loop and a flip of the side chain of Arg355, respectively. The co-evolutionary mutations identified (V344M, I354L) were found to be established in the PB2 gene of the pH1N1 viral population over the period 2010-2014. The study demonstrates the molecular basis for the enhanced m7GTP ligand binding affinity with the 344M-354L synergistic combination in PB2. Furthermore, the insight gained into understanding the molecular mechanism of cap binding in pH1N1 viruses may be useful for designing novel drugs targeting the PB2 cap binding domain.

Acute flaccid paralysis (AFP) associated with coxsackievirus type B3 (CV-B3) of the species Enterovirus B is an emerging concern worldwide. Although CV-B3-associated AFP in India has been demonstrated previously, the genomic characterization of these strains is unreported. Here, CV-B3 strains detected on the basis of the partial VP1 gene in 10 AFP cases and five asymptomatic contacts identified from different regions of south-western India during 2009-2010 through the Polio Surveillance Project were considered for complete genome sequencing and characterization. Phylogenetic analysis of complete VP1 gene sequences of global CV-B3 strains classified Indian CV-B3 strains into genogroup GVI, along with strains from Uzbekistan and Bangladesh, and into a new genogroup, GVII. Genomic divergence between genogroups of the study strains was 14.4 % with significantly lower divergence (1.8 %) within GVI (n = 12) than that within GVII (8.5 %) (n = 3). The strains from both AFP cases and asymptomatic contacts, identified mainly in coastal Karnataka and Kerala, belonged to the dominant genogroup GVI, while the GVII strains were recovered from AFP cases in north interior Karnataka. All study strains carried inter-genotypic recombination with the structural region similar to reference CV-B3 strains, and 5' non-coding regions and non-structural regions closer to other enterovirus B types. Domain II structures of 5' non-coding regions, described to modulate virus replication, were predicted to have varied structural folds in the two genogroups and were attributed to differing recombination patterns. The results indicate two distinct genomic compositions of CV-B3 strains circulating in India and suggest the need for concurrent analysis of viral and host factors to further understand the varied manifestations of their infections.

Japanese encephalitis virus (JEV) isolates from India phylogenetically belong to two genotypes, III and I. We used envelope gene sequences from GenBank, representing different states of India and other countries, to study the spatiotemporal transmission histories of these two JEV genotypes separately. Genotype III was found to have been successively introduced in the 1930s, 1950s and 1960s, followed by genotype I twice around 2003-2006. Changes in JEV disease patterns in India over the last five decades could thus be attributed to multiple introductions of JEV strains from neighboring Asian countries along with increased transmission potential due to altered ecological settings.

The envelope protein hemagglutinin (HA) of influenza viruses is primarily associated with host antibody and receptor interactions. The HA protein is known to maintain a functional balance with neuraminidase (NA), the other major envelope protein. Prior to 2007-2008, human seasonal H1N1 viruses possessing the NA H274Y mutation, which confers oseltamivir resistance, generally had low growth capability. Subsequently, secondary mutations that compensate for the deleterious effect of the NA H274Y mutation have been identified. The molecular mechanism of how the defect could be counteracted by these secondary mutations is not fully understood. We studied here the effect of three such mutations (T86K, K144E and R192K) in the HA protein, which are located at either the HA receptor binding site or in the H1N1 antigenic sites. Molecular docking and dynamics studies showed that, of the three mutations, the R192K mutation could have mediated neutralizing antibody escape and decreased receptor binding affinity, either or both of which may have contributed to increased viral fitness. The study suggests the molecular basis of enhanced viral fitness induced by secondary mutations in the evolution of oseltamivir-resistant influenza strains., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Patterns in virus dispersal and epidemiology of viral diseases can be revealed by phylogeographic studies. Currently knowledge about phylogeography of Dengue virus (DENV) Types 1 and 2 is limited. We carried out the phylogeographic analyses for DENV-1 and DENV-2, by the Bayesian Markov Chain Monte Carlo (MCMC) approach, with emphasis on Indian isolates in relation to the global evolutionary dynamics of the viruses. More than 250 E-gene sequences of each virus, available in GenBank, were used for the analyses. The study was focused on understanding the most likely geographical origin for the major genotypes and sub-lineages of DENV-1/DENV-2 and also the possible pathways in the dispersal of the virus. The results showed that for DENV-1, Southeast Asia was the most likely geographical origin and India was determined to be the ancestral location of the Cosmopolitan genotype circulating in India, Sri Lanka, West and East Africa, Caribbean region, East and Southeast Asia. For DENV-2, the ancestral source could not be precisely inferred. Further, in spite of the earliest isolate from Trinidad-1953 of the American genotype, it was depicted that India may have been the probable ancestor of this genotype. India was also determined to be the ancestral location of a subgroup of the Cosmopolitan genotype. It was noted that DENV-1 and DENV-2 were introduced into India during 1940s and 1910s respectively. Subsequently, dispersal of both the viruses between India and different regions including West, East and Central Africa, Southeast and East Asia and Caribbean was inferred. Overall, the current study provides insight into the spatial as well as temporal dynamics of dengue virus serotypes 1 and 2., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A nosocomial outbreak of Crimean Congo hemorrhagic fever (CCHF) was reported among humans in Ahmadabad district, Gujarat, India during January, 2011. In the present study we provide the complete genomic sequences of four CCHFV isolates derived from two human patients and two pools of Hyalomma anatolicum ticks during the period of this outbreak and the complete S segment sequence of two retrospective human serum samples, positive for CCHFV in 2010. Sequence-based molecular characterization of the Indian CCHFV showed that they possessed the functional motifs known to occur in the S, M and L gene segment products as in other CCHF viruses. The S segment of the six Indian CCHF viruses showed 99.8% nucleotide identity. Notably both tick isolates shared 100% nucleotide identity with one of the Indian human isolates of 2011. Phylogenetic analysis based on the S segment demonstrated that the Indian CCHFV isolates formed a distinct cluster in the Asian-Middle East group IV of CCHF viruses. The S segment was closest to a Tajikistan strain TADJ/HU8966 of 1990 (98.5% nucleotide identity) and was of South-Asia 2 type while the M segment was of type M2. Both M and L segments were closest to an Afghanistan strain Afg09-2990 of 2009 (93% and 98% nucleotide identity, respectively). The Indian isolates were thus identified as a South-Asia 2/M2 far-east virus combination and the differing parental origin in the S and L/M segments is suggestive that it may be an intra-genotypic reassortant. Molecular clock studies further revealed that the ancestry of the viruses was not very recent and dated back to about 33years on the basis of the S segment while it was about 15years based on the M segment. Thus though the 2011 outbreak may not have resulted from a very recent introduction, considering that so far there is no evidence of multiple circulating strains in the country, the possibility of a recent re-introduction of the virus from any of the neighboring countries cannot be ruled out. The study thus warrants the need for continued surveillance and increased sampling of CCHFV in different parts of the country., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The objective of this study was to examine the prevalence of obesity and overweight in urban school children in Kochi, Kerala, South India. Three schools from the city were selected representing upper, middle and lower socioeconomic groups and the children aged 6-15 years of age were interviewed. The prevalence of obesity was 3.0% for boys and 5.3% for girls. The prevalence of obesity (7.5%) and overweight (21.9%) were highest among high income group and lowest (1.5% and 2.5%) among low income group. Prevalence of obesity and overweight was found to be higher in the high income group and among girls.

The Chandipura virus (CHPV) belonging to the Vesiculovirus genus and Rhabdoviridae family, has recently been associated with a number of encephalitis epidemics, with high mortality in children, in different parts of India. No full length genome sequences of CHPV isolates were available in GenBank and little is known about the molecular markers for pathogenesis. In the present study, we provide the complete genomic sequences of four isolates from epidemics during 2003-2007. These sequences along with the deduced sequence of the prototype isolate of 1965 were analysed using phylogeny, motif search, homology modeling and epitope prediction methods. Comparison with other rhaboviruses was also done for functional extrapolations. All CHPV isolates clustered with the Isfahan virus and maintained several functional motifs of other rhabdoviruses. A notable difference with the prototype vesiculovirus, Vesicular Stomatitis Virus was in the L-domain flanking sequences of the M protein that are known to be crucial for interaction with host proteins. With respect to the prototype isolate, significant additional mutations were acquired in the 2003-2007 isolates. Several mutations in G mapped onto probable antigenic sites. A mutation in N mapped onto regions crucial for N-N interaction and a putative T-cell epitope. A mutation in the Casein kinase II phosphorylation site in P may attribute to increased rates of phosphorylation. Gene junction comparison revealed changes in the M-G junction of all the epidemic isolates that may have implications on read-through and gene transcription levels. The study can form the basis for further experimental verification and provide additional insights into the virulence determinants of the CHPV.

The indigenous transmission of the 2009 pandemic H1N1 (pH1N1) virus in India made it as one of the major sub-types in circulation. Genetic characterization indicated that the viruses predominantly clustered in clade 7, the globally most widely circulating pH1N1 clade. It is imperative to continue monitoring the genetic make-up of the pH1N1 viruses to understand their adaptability and evolutionary dynamics in the country. We characterized 31 full genomes and 94 hemagglutinin (HA) sequences of the pH1N1 viruses from various regions of India (May 2009-October 2010). Among the newly identified mutations reported in the pH1N1 viruses that could alter the viral fitness, E374K in the HA was increasingly noted in 35 Indian isolates beyond September 2009 and its co-occurrence with D97N or V30A was also observed in the more recent isolates. Molecular clock analysis based on all Indian isolates and closely related global representatives indicated higher substitution rates (∼ 7.1 × 10(-3) subs/site/year) when compared to an earlier report. Several independent introductions were noted within the country along with considerable evidence of indigenous evolution during the latter period of the study. The estimate for the mean age of the common ancestor of all the pandemic isolates dated to around August 2008 correlating well with the global estimate. Evidence for adaptive evolution in the HA was observed in the clade 7 isolates at the 'Ca' antigenic site that may have implications for future re-evaluation of the vaccine composition. The study thus warrants the need for continued surveillance and genetic characterization of whole genome sequences to detect any possible reassortment events that might further contribute to the viral fitness of the pH1N1 viruses., (Copyright © 2011 Elsevier B.V. All rights reserved.)

The Envelope glycoprotein (E-protein) of Japanese encephalitis virus (JEV) is the major structural component on the virion surface and is a primary target for the host immune system. Two monoclonal antibodies (MAbs) NHA-I (IgG2b) and NHA-II (IgM) against JEV (Indian strain 733913) were earlier developed in the authors' laboratory and found to be cross-reactive to nuclear histones. However, the epitope specificity of these MAbs has remained unknown. The present study was carried out to delineate the epitopes recognised by these MAbs on the E-protein of JEV strain 733913. The variable regions of the NHA-I and NHA-II were sequenced and the tertiary structures predicted. Molecular docking of the MAbs with the structural model of the JEV E-protein demonstrated that NHA-I binds to a predicted antigenic determinant (residue position 18-33) in domain-I. To understand the epitope specificity and check for possible cross-reactivity of these MAbs, comparative analysis of interactions with the known crystallographic structure of the West Nile virus (WNV) E-protein was also carried out. The studies predicted a differential binding of NHA-I but not of NHA-II between JEV and WNV. Mutagenesis studies could help analyse the specificity of NHA-I. The NHA-II appears to be cross-reactive as it docked in the groove region between domains I and III of both the JEV and WNV E-proteins. In laboratory assays, namely, ELISA and immunofluorescence assay both the MAbs reacted equally with JEV while the NHA-I did not show any reactivity with WNV. In silico results were thus validated by laboratory experiments. The present study would help in better understanding of virus-host interactions at the molecular level, and also be useful for the future design of vaccines as well as peptide based diagnostics., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Antigenic drift and shift involving the surface proteins of Influenza virus gave rise to new strains that caused epidemics affecting millions of people worldwide over the last hundred years. Variations in the membrane proteins like Hemagglutinin (HA) and Neuraminidase (NA) necessitates new vaccine strains to be updated frequently and poses challenge to effective vaccine design. Though the HA protein, the primary target of the human immune system, has been well studied, reports on the antigenic variability in the other membrane protein NA are sparse. In this paper we investigate the molecular basis of antigenic drift in the NA protein of the Influenza A/H3N2 vaccine strains between 1968 and 2009 and proceed to establish correlation between antigenic drift and antigen-antibody interactions. Sequence alignments and phylogenetic analyses were carried out and the antigenic variability was evaluated in terms of antigenic distance. To study the effects of antigenic drift on the protein structures, 3D structure of NA from various strains were predicted. Also, rigid body docking protocol has been used to study the interactions between these NA proteins and antibody Mem5, a 1998 antibody.

The molecular characteristics of hepatitis A virus (HAV) have been studied widely though there is a paucity of data on the correlation with virological and serological findings. In the present study, the whole genome of an Indian HAV strain associated with Guillain-Barré syndrome (GBS) was characterized vis-à-vis two other Indian HAV genotype IIIA strains, associated with a self-limiting disease. The percentage nucleotide divergence displayed by the Indian strains (CP-IND, PN-IND, and GBS-IND) varied from 3 to 6, whereas the percentage amino acid divergence varied from 0.1 to 0.7 as compared to the other HAV IIIA strains (n = 5) available in the GenBank. The GBS-IND strain showed an increased rate of nonsynonymous substitutions as well as a larger number of unique and heterologous amino acid substitutions compared to the HAV IIIA GenBank strains. These amino acid substitutions in the GBS-IND strain were detected in a nonstructural protein (2C-251F) and the B-cell epitope regions of structural proteins (VP1-29E, VP1-91S, VP3-50Y, and VP4-5S). In a comparative analysis of HAV strains, homology-based models of the capsid proteins indicated a localized alteration in the surface charge distribution on the VP1 protein of GBS-IND strain and involvement of its unique amino acid substitutions in the predicted antigenic determinants. Overall, the study suggests that the unique amino acid substitutions in the GBS-IND strain may have contributed to neutralization escape of the virus leading to a longer duration of viremia.

Background: The Influenza A pandemic H1N1 2009 (H1N1pdm) virus appeared in India in May 2009 and thereafter outbreaks with considerable morbidity and mortality have been reported from many parts of the country. Continuous monitoring of the genetic makeup of the virus is essential to understand its evolution within the country in relation to global diversification and to track the mutations that may affect the behavior of the virus., Methods: H1N1pdm viruses were isolated from both recovered and fatal cases representing major cities and sequenced. Phylogenetic analyses of six concatenated whole genomes and the hemagglutinin (HA) gene of seven more isolates from May-September 2009 was performed with reference to 685 whole genomes of global isolates available as of November 24, 2009. Molecular characterization of all the 8 segments was carried out for known pathogenic markers., Results: The first isolate of May 2009 belonged to clade 5. Although clade 7 was the dominant H1N1pdm lineage in India, both clades 6 and 7 were found to be co-circulating. The neuraminidase of all the Indian isolates possessed H275, the marker for sensitivity to the neuraminidase inhibitor Oseltamivir. Some of the mutations in HA are at or in the vicinity of antigenic sites and may therefore be of possible antigenic significance. Among these a D222G mutation in the HA receptor binding domain was found in two of the eight Indian isolates obtained from fatal cases., Conclusions: The majority of the 13 Indian isolates grouped in the globally most widely circulating H1N1pdm clade 7. Further, correlations of the mutations specific to clade 7 Indian isolates to viral fitness and adaptability in the country remains to be understood. The D222G mutation in HA from isolates of fatal cases needs to be studied for pathogenicity.

This study reports the phylogeny, selection pressure, genotype replacement and molecular clock analyses of many previously unstudied dengue type 2 virus (DENV-2) strains, isolated in India over a time span of almost 50 years (1956-2005). Analysis of complete envelope (E) gene sequences of 37 strains of DENV-2 from India, together with globally representative strains, revealed that the American genotype, which circulated predominantly in India during the pre-1971 period, was then replaced by the Cosmopolitan genotype. Two previously unreported amino acid residues, one in the American (402I) and one in the Cosmopolitan (126K) genotypes, known to be involved functionally in the cellular tropism of the virus, were shown to be under positive selection pressure. The rate of nucleotide substitution estimated for DENV-2 was 6.5x10(-4) substitutions per site year(-1), which is comparable with earlier estimates. The time to the most recent common ancestor of the pre-1971 Indian strains and the American genotype was estimated to be between 73 and 100 years (1905-1932), which correlates with the historical record of traffic between India and South America and suggests transportation of the virus from the Americas. Post-1971 Indian isolates formed a separate subclade within the Cosmopolitan genotype. The estimated time to the most recent common ancestor of the Indian Cosmopolitan strains was about 47 years, with further estimates indicating the migration of DENV-2 from India to countries across the Indian ocean between 1955 and 1966. Overall, the present study increases our understanding of the events leading to the establishment and dispersal of the two genotypes in India.

Widespread infection of highly pathogenic avian influenza A H5N1 was reported from backyard and commercial poultry in West Bengal (WB), an eastern state of India in early 2008. Infection gradually spread to Tripura, Assam and Sikkim, the northeastern states, with 70 outbreaks reported between January 2008 and May 2009. Whole genome sequence analysis of three isolates from WB, one isolate from Tripura along with the analysis of hemagglutinin (HA) and neuraminidase (NA) genes of 17 other isolates was performed during this study. In the HA gene phylogenetic tree, all the 2008-09 Indian isolates belonged to EMA3 sublineage of clade 2.2. The closest phylogenetic relationship was found to be with the 2007-09 isolates from Bangladesh and not with the earlier 2006 and 2007 Indian isolates implying a third introduction into the country. The receptor-binding pocket of HA1 of two isolates from WB showed S221P mutation, one of the markers predicted to be associated with human receptor specificity. Two substitutions E119A (2 isolates of WB) and N294S (2 other isolates of WB) known to confer resistance to NA inhibitors were observed in the active site of neuraminidase. Several additional mutations were observed within the 2008-09 Indian isolates indicating genetic diversification. Overall, the study is indicative of a possible endemicity in the eastern and northeastern parts of the country, demanding active surveillance specifically in view of the critical mutations that have been observed in the influenza A H5N1 viruses.

Background: A focal H5N1 outbreak in poultry was reported from Manipur, a north-eastern state, of India, in 2007. The aim of this study was to genetically characterize the Manipur isolate to understand the relationship with other H5N1 isolates and to trace the possible source of introduction of the virus into the country., Results: Characterization of the complete genome revealed that the virus belonged to clade 2.2. It was distinctly different from viruses of the three EMA sublineages of clade 2.2 but related to isolates from wild migratory waterfowl from Russia, China and Mongolia. The HA gene, had the cleavage site GERRRRKR, earlier reported in whooper swan isolates from Mongolia in 2005. A stop codon at position 29 in the PB1-F2 protein could have implications on the replication efficiency. The acquisition of polymorphisms as seen in recent isolates of 2005-07 from distinct geographical regions suggests the possibility of transportation of H5N1 viruses through migratory birds., Conclusion: Considering that all eight genes of the earlier Indian isolates belonged to the EMA3 sublineage and similar strains have not been reported from neighbouring countries of the subcontinent, it appears that the virus may have been introduced independently.

Chikungunya (CHIK) virus reemerged during 2005-07 as an important pathogen causing massive disease outbreaks affecting India and several countries of the Indian Ocean. Knowledge of the evolutionary rates and divergence times of the CHIK virus may help to better understand the disease epidemiology. Considering the limited availability of such information, we estimated the substitution rates and the ancestral times for all the CHIK genotypes and also the time to the most recent common ancestor (tMRCA) of the 2005-07 isolates. Using whole genomes and partial E1 gene datasets, we applied the Bayesian Markov Chain Monte Carlo (MCMC) framework that explicitly accounts for lineage-specific evolutionary rates through the use of 'relaxed' molecular clock models. Under a constant population relaxed clock model, the evolutionary timescale of CHIK viruses in this study was estimated to be in the last 300 years. The progenitor of the 2005-07 viruses was found to have existed around 9 years ago, and to have originated from Central Africa. The presence of a strain in India in 2000 that bears 99% identity with a Ugandan strain of 1982, which correlates with the tMRCA of the Indian and Indian Ocean isolates, confirms our earlier report that the progenitor of the 2005-07 isolates originates from Uganda's neighbourhood. The 'A226V' mutation that existed in the Indian Ocean isolates since late 2005 was found to occur only in the 2007 isolate from India. The study confirms the epidemiological data, specifically with regard to the re-emergence of CHIKV and throws light on the evolutionary dynamics of CHIK viruses.

The inner capsid protein VP6 of group A rotavirus possesses group and subgroup epitope specificities. Avian rotaviruses have a unique VP6 that is antigenically different from its mammalian counterpart. The lack of information on the VP6 protein of chicken rotavirus strain, CH2, at the genetic and antigenic level was a major motivation for this work. Sequencing of the complete cDNA of the VP6 gene of CH2, revealed a nucleotide (amino acid) identity that varied from 78.3 to 98.5% (86.4-98.2%) when compared with other avian rotaviruses. Regardless of its host origin dissimilarity, CH2 VP6 showed a close sequence homology (97.4-98.2%) with turkey and pigeon rotaviruses. Homology-based modeling of the CH2 VP6 from the corresponding crystal structure of the bovine rotavirus, RF strain, demonstrated that the hypervariable region (residue 228-240) does have a critical role in strain specific antigenic characteristics of avian and mammalian rotaviruses. A predicted conformational epitope encompasses experimentally characterized group and subgroup epitopes suggesting that it is a major antibody binding site on the VP6 protein. The VP6 structure modeling and conformational epitope prediction together with enzyme immuno assay of SG MAbs placed CH2 in SGI/II. The study may be helpful in designing peptides for group A rotavirus diagnostic assays and to achieve heterotypic protection against rotavirus serotypes.

An outbreak of highly pathogenic avian influenza A (H5N1) virus in poultry was reported from Nandurbar and Jalgaon districts of Maharashtra and adjoining areas of Uchhal in Gujarat and Burhanpur in Madhya Pradesh in India from January to April, 2006. In the present study, the full genome of two previously uncharacterized strains of H5N1 viruses isolated at the National Institute of Virology (NIV), Pune, from post-mortem tissues of chicken collected from Navapur, Nandurbar district during the outbreak, has been presented. All the genes belong to clade 2.2 of the Z genotype and are close to the 2006 isolates from Iran, Afghanistan, Mongolia, Italy, and Krasnodar. In a study reported earlier, based on the partial gene sequences of HA, the authors (Pattnaik et al.) hypothesized that the viruses in Jalgaon and Navapur, causing outbreaks 12 days apart, were introduced at different times from different sources. However, our Navapur isolates are closer to the isolate reported from Jalgaon than that from Navapur. Molecular markers suggest that the isolates are sensitive to both drugs Oseltamivir and Amantadine. Amino acid residues responsible for pathogenesis, glycosylation, and receptor binding have also been discussed. The relationship between the Indian viruses and those in the East Africa/West-Asia flyway of migratory birds and the position of Nandurbar in this route suggests that the viruses in India may have been introduced through migratory birds although the role of trade as a possible route of introduction of the virus cannot be ruled out.

Intraventricular hemorrhage is a common complication of prematurity. Posthemorrhagic ventricular dilation (PHVD) has a high rate of disability and no safe and effective treatment. Its pathogenesis is poorly understood, largely because of the lack of a satisfactory animal model. We have developed a model of neonatal PHVD in the rat. Seven-day-old (P7) Wistar rat pups were given 80-microl injections of citrated rat blood or artificial cerebrospinal fluid (CSF) into alternate lateral ventricles on P7 and P8. Intracranial pressure was monitored and increased briefly by over 8-fold. Some rats received further 10-microl intraventricular injections of India ink on P21. Animals were weighed daily and simple neurologic tests performed. On P21 (or P22 if India ink had been injected), the rats were perfusion-fixed and blocks processed for paraffin histology. Sixty-five percent of pups injected with blood and 50% injected with artificial CSF developed dilated lateral ventricles, with patchy loss of ependyma, marked astrocytic gliosis, and rarefaction of periventricular white matter. India ink injection revealed slow transit of CSF from the dilated lateral ventricles but eventual passage into the subarachnoid space. Pups that had received intraventricular injections but did not develop ventricular dilation nonetheless had lighter brains than littermate controls (p < 0.001). Body weights were not significantly different from controls. Hydrocephalic animals had reduced motor performance as assessed by a grip traction test (p = 0.0002). This model is well suited to studying the pathogenesis of PHVD.

Objective: To survey physicians' anticoagulation preferences in patients with chronic atrial fibrillation who are undergoing elective surgery., Materials and Methods: A survey was performed that asked physicians to provide pre- and postoperative anticoagulation preferences for two clinical scenarios of patients with chronic atrial fibrillation (high stroke risk, low stroke risk) undergoing elective surgery. In addition to the interruption of warfarin therapy, perioperative anticoagulation options were as follows: a) in-hospital full dose intravenous heparin; b) outpatient full dose subcutaneous unfractionated heparin or low molecular weight heparin (LMWH); c) low dose unfractionated heparin or LMWH (postoperative only); d) nothing other than stopping warfarin preoperatively and restarting it postoperatively; or e) another anticoagulant strategy., Results: In the high stroke risk scenario, the proportions of respondents preferring anticoagulation options a, b, d and e in the preoperative period were 24%, 20%, 54% and 2%, respectively; the proportions preferring options a, b, c, d and e in the postoperative period were 35%, 13%, 15%, 35% and 1%, respectively. In the low stroke risk scenario, the proportions of respondents preferring options a, b, d and e in the preoperative period were 7%, 10%, 80% and 3%, respectively; the proportions preferring options a, b, c, d and e in the postoperative period were 11%, 9%, 10%, 68% and 2%, respectively., Conclusions: In patients with chronic atrial fibrillation who underwent elective surgery, perioperative anticoagulant management preferences varied widely in patients at high risk for stroke, but were more uniform and less aggressive in patients at low risk for stroke.

Study Objective: To determine physicians' anticoagulation preferences in patients with a mechanical heart valve who are undergoing elective surgery, and to determine the effect of different risks of thromboembolism (TE) and postoperative bleeding on anticoagulation preferences., Design: Mail survey of physicians who prescribe anticoagulant therapy., Methods and Results: Physicians were asked to provide anticoagulation preferences in four clinical scenarios of patients with a mechanical heart valve who are undergoing elective surgery. Physicians were asked to select from three preoperative anticoagulation options (two aggressive, one less aggressive) and four postoperative anticoagulation options (two aggressive, two less aggressive). IV heparin was the most frequently selected anticoagulation option. Depending on the scenario, it was preferred by 39 to 79% of respondents for preoperative anticoagulation therapy, and by 44 to 84% of respondents for postoperative anticoagulant therapy. The risk of TE had a strong influence on anticoagulation preferences: more respondents preferred aggressive anticoagulant management in high-risk compared with low-risk TE scenarios (p < 0.001). Anticoagulation preferences were not influenced by the risk of bleeding: the proportion of respondents who preferred aggressive anticoagulant management did not differ in high-risk and low-risk bleeding scenarios (p > 0.05). Of respondents who preferred IV heparin for postoperative anticoagulation therapy, the risk of bleeding influenced the timing of heparin initiation: fewer respondents preferred early heparin initiation (within 12 h after surgery) in high-risk compared with low-risk bleeding scenarios (p < 0.01)., Conclusions: (1) Preoperative and postoperative IV heparin were the most frequently selected anticoagulation options. (2) The risk of TE, but not the risk of bleeding, influenced the aggressiveness of anticoagulant management. (3) If IV heparin was selected, the risk of bleeding influenced the timing of heparin initiation.