Immunogenicity and protective efficacy of inactivated SARS-CoV-2 vaccine candidate, BBV152 in rhesus macaques

The COVID-19 pandemic is a global health crisis that poses a great challenge to the public health system of affected countries. Safe and effective vaccines are needed to overcome this crisis. Here, we develop and assess the protective efficacy and immunogenicity of an inactivated SARS-CoV-2 vaccine in rhesus macaques. Twenty macaques were divided into four groups of five animals each. One group was administered a placebo, while three groups were immunized with three different vaccine candidates of BBV152 at 0 and 14 days. All the macaques were challenged with SARS-CoV-2 fourteen days after the second dose. The protective response was observed with increasing SARS-CoV-2 specific IgG and neutralizing antibody titers from 3^rd-week post-immunization. Viral clearance was observed from bronchoalveolar lavage fluid, nasal swab, throat swab and lung tissues at 7 days post-infection in the vaccinated groups. No evidence of pneumonia was observed by histopathological examination in vaccinated groups, unlike the placebo group which exhibited interstitial pneumonia and localization of viral antigen in the alveolar epithelium and macrophages by immunohistochemistry. This vaccine candidate BBV152 has completed Phase I/II (NCT04471519) clinical trials in India and is presently in phase III, data of this study substantiates the immunogenicity and protective efficacy of the vaccine candidates.

Proactive preparedness for Cat Que virus: An Orthobunyavirus existing in India

Background & objectives:

The presence of Cat Que virus (CQV) in Culex mosquitoes and pigs has been reported in China and Vietnam. Due to the spread of similar species of the Culex mosquitoes in India, there is a need to understand the replication kinetics of this virus in mosquito models. As a part of preparedness and to identify the presence of this CQV in humans and swine, this study was carried out to develop diagnostic tests.

Methods:

Serological and molecular diagnostic assays were developed for testing the mosquito population, human and swine serum samples. In this line, RNA-dependent RNA polymerase (L), glycoprotein (M) and nucleocapsid (S) genes-based reverse transcription-polymerase chain reaction (RT-PCR) assays were developed for CQV. Real-time RT-PCR was used for screening of retrospectively collected human serum samples (n=1020) with acute febrile illness during 2014-2017. Simultaneously, an in-house anti-CQV swine and human IgG ELISAs were also developed to detect anti-CQV IgG antibody. Human serum samples (n=883) with post-onset of disease (POD) >4 days and swine serum samples (n=459) were tested for the presence of anti-CQV IgG antibodies. CQV NIV 612,045 isolate was used for susceptibility and replication kinetics experiment using three different species of mosquitoes to understand its behaviour in Indian mosquitoes.

Results:

All human serum samples (n=1020) screened for the presence of CQV using real-time RT-PCR were found to be negative. Anti-CQV IgG antibody positivity was recorded in two of 883 human serum samples tested. Virus susceptibility experiments indicated that three species of mosquito, namely Aedes aegypti, Culex quinquefasciatus and Cx. tritaeniorhynchus supported multiplication of CQV by intrathoracic as well as artificial membrane/oral feeding routes.

Interpretation & conclusions:

Anti-CQV IgG antibody positivity in human serum samples tested and the replication capability of CQV in mosquitoes indicated a possible disease causing potential of CQV in Indian scenario. Screening of more human and swine serum samples using these assays is required as a proactive measure for understanding the prevalence of this neglected tropical virus.

Zika virus Pathogenesis in Infant Mice after Natural Transmission by the Bite of Infected Mosquitoes

OBJECTIVES

The objective of this study was to understand natural disease progression in infant CD1 mice after the bite of Aedes aegypti mosquitoes infected by the Zika virus (ZIKV, MR-766 strain).

METHODS

A. aegypti mosquitoes were experimentally infected with ZIKV MR-766 strain via the oral feeding route. Infected mosquitoes were allowed to feed on infant CD1 mice. Sick mice were euthanized, and their organs were collected and subjected to real-time RT-PCR, histo-pathology, and immunohistochemistry.

RESULTS

Clinical symptoms appeared in mice after 4-5 days of being bitten by mosquitoes, following which they were euthanized. Real-time RT-PCR analysis showed the presence of viral RNA in various organs such as the brain, liver, kidney, spleen, lungs, and intestines of the mice. The brain tissue specimens showed higher viral loads as determined by threshold values (Ct value) in the real-time RT-PCR assay. Histopathological and immunohistochemistry studies also revealed the presence of the virus and associated lesions in the brain, indicating that ZIKV shows tropism for neuronal tissue.

CONCLUSIONS

This study demonstrates ZIKV pathogenesis in infant CD1 mice and that these mice are highly susceptible to natural infection with this ZIKV strain.

Patents on Endophytic Fungi

BACKGROUND

Endophytic fungi are taxonomically and ecologically heterogeneous group of organisms, mainly belonging to the Ascomycotina and Deuteromycotina. Endophytes usually produce the enzymes necessary for the colonization of plant tissues. Endophytes are able to utilize components of plant cells without disturbing host metabolism, which is confirmed by isozyme analysis and studies on substrate utilization. The patents related to enzymes and metabolites produced by endophytic fungi are associated with their ecological significance. Application of metabolites and growth promoting factors produced from endophytic fungi, in the pharmaceutical and agricultural industries, is now well established. The patents on secretion of extracellular enzymes in vitro by endophytic fungi needed for cell wall degradation, support the hypothesis that fungal endophytes represent a group of organisms specialized to live within plant tissue.

OBJECTIVE

This review presents the patents granted on different aspects of endophytic fungi for the last 11 years. This expresses the scenario and impact of these patents regarding significance in human society.

CONCLUSION

In the last few years, research and inventions regarding the different aspects of endophytic fungi beneficial for host plant as well as for human beings have been carried out, which is supported by the increasing number of patents granted on endophytic fungi.

Isolation of Tioman virus from Pteropus giganteus bat in North-East region of India

Bat-borne viral diseases are a major public health concern among newly emerging infectious diseases which includes severe acute respiratory syndrome, Nipah, Marburg and Ebola virus disease. During the survey for Nipah virus among bats at North-East region of India; Tioman virus (TioV), a new member of the Paramyxoviridae family was isolated from tissues of Pteropus giganteus bats for the first time in India. This isolate was identified and confirmed by RT-PCR, sequence analysis and electron microscopy. A range of vertebrate cell lines were shown to be susceptible to Tioman virus. Negative electron microscopy study revealed the "herringbone" morphology of the nucleocapsid filaments and enveloped particles with distinct envelope projections a characteristic of the Paramyxoviridae family. Sequence analysis of Nucleocapsid gene of TioV demonstrated sequence identity of 99.87% and 99.99% nucleotide and amino acid respectively with of TioV strain isolated in Malaysia, 2001. This report demonstrates the first isolation of Tioman virus from a region where Nipah virus activity has been noticed in the past and recent years. Bat-borne viruses have become serious concern world-wide. A Survey of bats for novel viruses in this region would help in recognizing emerging viruses and combating diseases caused by them.

Persistence of viral RNA in chikungunya virus-infected Aedes aegypti (Diptera: Culicidae) mosquitoes after prolonged storage at 28°C

Experiments were conducted to determine the persistence of chikungunya viral (CHIKV) RNA in experimentally infected Aedes aegypti mosquitoes stored for prolonged periods at 28°C. Intra-thoracically inoculated mosquitoes with confirmed positivity were killed by quick freezing at -80°C, applied to sticky tape, and stored at 28°C with 80 ± 5% relative humidity (RH). At weekly intervals, five mosquitoes were removed from the tape randomly and assayed individually for detection of viral RNA by reverse transcriptase-polymerase chain reaction (RT-PCR). CHIKV RNA was detected up to 12 weeks in dry mosquitoes by RT-PCR. Virus could not be isolated either in cell culture or in the suckling Swiss-albino mouse system at any stage. This study demonstrated the persistence of CHIKV viral RNA up to 12 weeks when stored at 28°C with RH 80 ± 5%. This finding will have significance in CHIKV surveillance programs in mosquito populations or field-based studies in countries where maintenance of a cold chain is a concern.

Venereal transmission of chikungunya virus by Aedes aegypti mosquitoes (Diptera: Culicidae)

Experiments were conducted to demonstrate the role of male Aedes aegypti mosquitoes in the maintenance and transmission of chikungunya virus (CHIKV) to female mosquitoes. We demonstrated that infected male mosquitoes are capable of infecting females during mating. The infection rate in female mosquitoes was 11% when virgin female mosquitoes were allowed to coinhabit with infected males. The body suspension of venereally infected female mosquitoes induced illness in infant Swiss albino mice, which demonstrated the infectivity of the venereally transmitted virus. The presence of CHIKV in the brains of the ill mice was confirmed by a reverse transcription-polymerase chain reaction specific for partial sequences of nonstructural protein 4 and envelope 1 genes. In the light of the recent report of transovarial transmission of CHIKV in mosquitoes, although at a lower level, this finding has significance because it may help in transmission of the virus to females venereally to start a new infection cycle.

Assessment of Secondary Metabolites in In vitro Regenerated Plantlets of Oroxylum indicum (L.) Vent

Flavonoids  baicalein and baicalein-7-o-glucoside were estimated in in vitro raised (six months old) as well as nature grown (12 months old) plants of Oroxylum indicum (L.) Vent. Multiple shoot formation and elongation were obtained from axillary and apical bud explants of O. indicum on MS containing BAP (1 mg/l)  and AgNO3 (2 mg/l). Rooting of the regenerated  shoots  was achieved  on medium (half strength) containing IBA (1 mg/l) and AgNO3 (1 mg/l). A quantitative HPLC analysis of methanolic extract of leaf and root  indicated the enhancement of baicalein-7-o glucoside in in vitro raised root and leaf of Oroxylum indicum.  Key words: Assessment, Secondary metabolites, Regenerated plantlets, Oroxylum indicum D.O.I. 10.3329/ptcb.v20i1.5961 Plant Tissue Cult. & Biotech. 20(1): 21-28, 2010 (June)

Cost of neutropenic complications of chemotherapy

BACKGROUND

Cost of neutropenic complications of myelosuppressive chemotherapy has been reported to be substantial. Prior research, however, has focused on initial hospitalization only and has failed to account for follow-on care.

PATIENTS AND METHODS

Using a US health-care claims database, all adult cancer patients who received a course of chemotherapy were identified. For each such patient, each unique cycle of chemotherapy within the course and each occurrence of neutropenic complications within these cycles were characterized. Patients developing neutropenic complications in a given cycle (neutropenia patients), starting with the first, were matched (1:1) to those who did not develop neutropenic complications in that cycle (comparison patients), and health-care costs (i.e. expenditures) were tallied for each matched pair.

RESULTS

Neutropenia patients (n = 373) and comparison patients were similar in terms of baseline characteristics. Costs of neutropenia-related care were $12,397 (95% confidence interval $10,274-$14,754) higher for neutropenia versus comparison patients [$14,407 ($12,357-$16,743) versus $2010 ($1490-$2553)]. Among neutropenia patients, mean cost of initial hospitalization for neutropenic complications was $7813 ($6537-$9379); cost of all subsequent neutropenia-related care averaged $6594 ($5217-$8272).

CONCLUSIONS

Neutropenic complications of myelosuppressive chemotherapy are costly. Prior research focusing on initial hospitalization only may have underestimated the cost of these complications by as much as 40%.

Preparedness for clinical practice: reports of graduating residents at academic health centers

CONTEXT

Medical educators are seeking improved measures to assess the clinical competency of residents as they complete their graduate medical education.

OBJECTIVE

To assess residents' perceptions of their preparedness to provide common clinical services during their last year of graduate medical education.

DESIGN, SETTING, AND PARTICIPANTS

A 1998 national survey of residents completing their training in 8 specialties (internal medicine, pediatrics, family practice, obstetrics/gynecology, general surgery, orthopedic surgery, psychiatry, and anesthesiology) at academic health centers in the United States. A total of 2626 residents responded (response rate, 65%).

MAIN OUTCOME MEASURES

Residents' reports of their preparedness to perform clinical and nonclinical tasks relevant to their specialties.

RESULTS

Residents in all specialties rated themselves as prepared to manage most of the common conditions they would encounter in their clinical career. However, more than 10% of residents in each specialty reported that they felt unprepared to undertake 1 or more tasks relevant to their disciplines, such as caring for patients with human immunodeficiency virus/acquired immunodeficiency syndrome or substance abuse (family practice) or nursing home patients (internal medicine); performance of spinal surgery (orthopedic surgery) or abdominal aortic aneurysm repair (general surgery); and management of chronic pain (anesthesiology).

CONCLUSIONS

Overall, residents in their last year of training at academic health centers rate their clinical preparedness as high. However, opportunities for improvement exist in preparing residents for clinical practice.

Residents' preferences and preparation for caring for underserved populations

Access to care by low-income persons and residents of rural and poor inner-city areas is a persistent problem, yet physicians tend to be maldistributed relative to need. The objectives were to describe preferences of resident physicians to locate in underserved areas and to assess their preparedness to provide service to low-income populations. A national survey was made of residents completing their training in eight specialties at 162 US academic health center hospitals in 1998, with 2,626 residents responding. (Of 4,832 sampled, 813 had invalid addresses or were no longer in the residency program. Among the valid sample of 4,019, the response rate was 65%.) The percentage of residents ranking public hospitals, rural areas, and poor inner-city areas as desirable employment locations and the percentage feeling prepared to provide specified services associated with indigent populations were ascertained. Logistic regressions were used to calculate adjusted percentages, controlling for sex, race/ethnicity, international medical graduate (IMG) status, plans to subspecialize, ownership of hospital, specialty, and exposure to underserved patients during residency. Only one third of residents rated public hospitals as desirable settings, although there were large variations by specialty. Desirability was not associated with having trained in a public hospital or having greater exposure to underserved populations. Only about one quarter of respondents ranked rural (26%) or poor inner-city (25%) areas as desirable. Men (29%, P <.01) and noncitizen IMGs (43%, P <.01) were more likely than others to prefer rural settings. Residents who were more likely to rate poor inner-city settings as desirable included women (28%, P =.03), noncitizen IMGs (35%, P =.01), and especially underrepresented minorities (52%, P <.01). Whereas about 90% or more of residents felt prepared to treat common clinical conditions, only 67% of residents in four primary care specialties felt prepared to counsel patients about domestic violence or to care for human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) or substance abuse patients (all 67%). Women were more likely than men to feel prepared to counsel patients about domestic violence (70% vs. 63%, P =.002) and depression (83% vs. 75%, P <.01). Underrepresented minority residents were more likely than other residents to feel prepared to counsel patients about domestic violence (P <.01) and compliance with care (P =.04). Residents with greater exposure to underserved groups were more prepared to counsel patients about domestic violence (P =.01), substance abuse (P =.01), and to treat patients with HIV/AIDS (P =.01) or with substance abuse problems (P <.01). This study demonstrates the need to expose graduate trainees to underserved populations and suggests a continuing role of minorities, women, and noncitizen physicians in caring for low-income populations.

Inhibition of TGF-beta-induced apoptosis by ethinyl estradiol in cultured, precision cut rat liver slices and hepatocytes

Ethinyl estradiol (EE) is a strong promoter of hepatocarcinogenesis in the rat. Treatment with EE and other hepatic promoters induces transient growth stimulation followed by growth inhibition (mitosuppression) in hepatocytes. Previously, we identified several genes whose transcript levels were increased during EE-induced mitosuppression, including transforming growth factor beta (TGF-beta), which inhibits growth and induces apoptosis in hepatocytes. Various hepatic promoters, including phenobarbital and several peroxisomal proliferators, have been shown to inhibit TGF-beta-induced apoptosis in rat hepatocytes. The goal of this study was to investigate whether EE is also an inhibitor of TGF-beta-induced apoptosis in rat hepatocytes. Several approaches to detect apoptosis were used, including the TUNEL assay, detection of high molecular weight DNA fragmentation by field inversion gel electrophoresis and determination of cytosolic cytochrome c levels by western analysis. TGF-beta-induced apoptosis in cultured, precision cut liver slices and hepatocytes of female rats. EE (</=3 microM) completely inhibited TGF-beta-induced apoptosis in these systems in the absence of cytotoxicity. These findings add EE to the list of several hepatic promoters that both induce TGF-beta while simultaneously inhibiting its ability to cause apoptosis.

Enhanced levels of several mitochondrial mRNA transcripts and mitochondrial superoxide production during ethinyl estradiol-induced hepatocarcinogenesis and after estrogen treatment of HepG2 cells

Ethinyl estradiol (EE) is a strong hepatic promoter and weak complete hepatocarcinogen. Among the effects on rat liver caused by chronic exposure to non-hepatotoxic doses of EE is an initial, transient increase in hepatocyte growth followed by a subsequent inhibition (mitosuppression) of basal and/or induced liver growth. To investigate the mechanism of EE-induced mitosuppression, we performed a differential display and identified 10 genes whose expression was increased 2- to 4-fold in EE-induced, mitosuppressed livers (Chen et al., Carcinogenesis, 17, 2783-2786, 1996). We found that one of these clones was homologous to nuclear genome-encoded mitochondrial ATP synthase subunit E. Here, we describe the identification of two additional cDNAs representing transcripts whose levels were elevated during EE-induced mitosuppression as mitochondrial DNA-encoded cytochrome c oxidase subunit III and ATP synthase 6. In addition, we found that EE, estradiol and the estradiol catechol metabolites, 4-OH-estradiol and 2-OH-estradiol, increased the levels of these and other mitochondrial genome-encoded transcripts in human hepatoma HepG2 cells. We also observed that this increase can be blocked by inhibition of cytochrome P450-mediated estrogen metabolism, and that this increase is accompanied by increased mitochondrial superoxide production, which reflects increased respiratory chain activity.