Vibrio cholerae Serogroup O139: Isolation from Cholera Patients and Asymptomatic Household Family Members in Bangladesh between 2013 and 2014

Background

Cholera is endemic in Bangladesh, with outbreaks reported annually. Currently, the majority of epidemic cholera reported globally is El Tor biotype Vibrio cholerae isolates of the serogroup O1. However, in Bangladesh, outbreaks attributed to V. cholerae serogroup O139 isolates, which fall within the same phylogenetic lineage as the O1 serogroup isolates, were seen between 1992 and 1993 and in 2002 to 2005. Since then, V. cholerae serogroup O139 has only been sporadically isolated in Bangladesh and is now rarely isolated elsewhere.

Methods

Here, we present case histories of four cholera patients infected with V. cholerae serogroup O139 in 2013 and 2014 in Bangladesh. We comprehensively typed these isolates using conventional approaches, as well as by whole genome sequencing. Phenotypic typing and PCR confirmed all four isolates belonging to the O139 serogroup.

Findings

Whole genome sequencing revealed that three of the isolates were phylogenetically closely related to previously sequenced El Tor biotype, pandemic 7, toxigenic V. cholerae O139 isolates originating from Bangladesh and elsewhere. The fourth isolate was a non-toxigenic V. cholerae that, by conventional approaches, typed as O139 serogroup but was genetically divergent from previously sequenced pandemic 7 V. cholerae lineages belonging to the O139 or O1 serogroups.

Conclusion

These results suggest that previously observed lineages of V. cholerae O139 persist in Bangladesh and can cause clinical disease and that a novel disease-causing non-toxigenic O139 isolate also occurs.     

Recombinant NAD-dependent SIR-2 Protein of Leishmania donovani: Immunobiochemical Characterization as a Potential Vaccine against Visceral Leishmaniasis

BackgroundThe development of a vaccine conferring long-lasting immunity remains a challenge against visceral leishmaniasis (VL). Immunoproteomic characterization of Leishmania donovani proteins led to the identification of a novel protein NAD+-dependent Silent Information regulatory-2 (SIR2 family or sirtuin) protein (LdSir2RP) as one of the potent immunostimulatory proteins. Proteins of the SIR2 family are characterized by a conserved catalytic domain that exerts unique NAD-dependent deacetylase activity. In the present study, an immunobiochemical characterization of LdSir2RP and further evaluation of its immunogenicity and prophylactic potential was done to assess for its possible involvement as a vaccine candidate against leishmaniasis.Conclusion/SignificanceThe immunobiochemical characterization strongly suggest the potential of rLdSir2RP as vaccine candidate against VL and supports the concept of its being effective T-cell stimulatory antigen.     

Investigating the Molecular Basis of Retinal Degeneration in a Familial Cohort of Pakistani Decent by Exome Sequencing

Purpose

To define the molecular basis of retinal degeneration in consanguineous Pakistani pedigrees with early onset retinal degeneration.

Methods

A cohort of 277 individuals representing 26 pedigrees from the Punjab province of Pakistan was analyzed. Exomes were captured with commercial kits and sequenced on an Illumina HiSeq 2500. Candidate variants were identified using standard tools and analyzed using exomeSuite to detect all potentially pathogenic changes in genes implicated in retinal degeneration. Segregation analysis was performed by dideoxy sequencing and novel variants were additionally investigated for their presence in ethnicity-matched controls.

Results

We identified a total of nine causal mutations, including six novel variants in RPE65, LCA5, USH2A, CNGB1, FAM161A, CERKL and GUCY2D as the underlying cause of inherited retinal degenerations in 13 of 26 pedigrees. In addition to the causal variants, a total of 200 variants each observed in five or more unrelated pedigrees investigated in this study that were absent from the dbSNP, HapMap, 1000 Genomes, NHLBI ESP6500, and ExAC databases were identified, suggesting that they are common in, and unique to the Pakistani population.

Conclusions

We identified causal mutations associated with retinal degeneration in nearly half of the pedigrees investigated in this study through next generation whole exome sequencing. All novel variants detected in this study through exome sequencing have been cataloged providing a reference database of variants common in, and unique to the Pakistani population.     

Facility Death Review of Maternal and Neonatal Deaths in Bangladesh

Objectives

To explore the experiences, acceptance, and effects of conducting facility death review (FDR) of maternal and neonatal deaths and stillbirths at or below the district level in Bangladesh.

Methods

This was a qualitative study with healthcare providers involved in FDRs. Two districts were studied: Thakurgaon district (a pilot district) and Jamalpur district (randomly selected from three follow-on study districts). Data were collected between January and November 2011. Data were collected from focus group discussions, in-depth interviews, and document review. Hospital administrators, obstetrics and gynecology consultants, and pediatric consultants and nurses employed in the same departments of the respective facilities participated in the study. Content and thematic analyses were performed.

Results

FDR for maternal and neonatal deaths and stillbirths can be performed in upazila health complexes at sub-district and district hospital levels. Senior staff nurses took responsibility for notifying each death and conducting death reviews with the support of doctors. Doctors reviewed the FDRs to assign causes of death. Review meetings with doctors, nurses, and health managers at the upazila and district levels supported the preparation of remedial action plans based on FDR findings, and interventions were planned accordingly. There were excellent examples of improved quality of care at facilities as a result of FDR. FDR also identified gaps and challenges to overcome in the near future to improve maternal and newborn health.

Discussion

FDR of maternal and neonatal deaths is feasible in district and upazila health facilities. FDR not only identifies the medical causes of a maternal or neonatal death but also explores remediable gaps and challenges in the facility. FDR creates an enabled environment in the facility to explore medical causes of deaths, including the gaps and challenges that influence mortality. FDRs mobilize health managers at upazila and district levels to forward plan and improve healthcare delivery.     

First report of bacterial leaf blight of jute (Corchorus capsularis L.) caused by Xanthomonas campestris pv. capsularii in India

Xanthomonas campestris pv. capsularii causing blight on jute (Corchorus capsularis) leaves was reported for the first time in India. The symptom of the disease initially observed was appearance of small angular brown leaf spots and later as blighted areas on leaf lamina. The disease-causing pathogen was isolated and identified on the basis of its colony morphology, PCR, sequencing and subsequent BLASTn analysis.     

Human Wharton's Jelly stem cell conditioned medium and cell‐free lysate inhibit human osteosarcoma and mammary carcinoma cell growth in vitro and in xenograft mice

Human Wharton's jelly stem cells (hWJSCs) were shown to inhibit the growth of human mammary carcinomas. It is not known whether cell‐free secretions or lysates of hWJSCs do the same on different cancers. They may be less controversial than cells to regulatory bodies for clinical application. We examined the influence of hWJSC conditioned medium (hWJSC‐CM) and cell‐free lysate (hWJSC‐CL) on two osteosarcoma cell lines (MG‐63, SKES‐1) in vitro and on human mammary carcinomas in immunodeficient mice. When exposed to hWJSC‐CL, increased vacuolations in MG‐63 and increased membrane fragmentation in SKES‐1 cells were observed, with greater cell death in SKES‐1. Exposure of SKES‐1 and MG‐63 cells to hWJSC‐CL showed significant decreases in cell proliferation of 46.48 ± 6.66% and 24.32 ± 5.67% respectively compared to controls. MG‐63 and SKES‐1 cells were annexin V‐FITC positive and SKES‐1 TUNEL positive following treatment with hWJSC‐CM and hWJSC‐CL. MG‐63 cells were positive and SKES‐1 cells negative for anti‐BECLIN‐1 and anti‐LC3B following treatment with hWJSC‐CM and hWJSC‐CL. RT‐PCR showed that the pro‐apoptotic BAX gene and the autophagy‐related ATG‐5 and BECLIN‐1 genes were up‐regulated while the anti‐apoptotic BCL2 and SURVIVIN genes were down‐regulated in MG‐63 and SKES‐1 cells treated with hWJSC‐CM and hWJSC‐CL. Injections of hWJSCs and hWJSC‐CM into mammary carcinomas in immunodeficient mice resulted in decreased tumor sizes and weights of 24.86 ± 6.05% to 37.03 ± 5.91% and 47.14 ± 7.36% to 55.09 ± 5.87% respectively at 6 weeks compared to controls. hWJSC‐CM and hWJSC‐CL inhibit mammary carcinoma and osteosarcoma cells via apoptosis and autophagy. J. Cell. Biochem. 114: 366–377, 2013. © 2012 Wiley Periodicals, Inc.     

Condurango-glycoside-A fraction of Gonolobus condurango induces DNA damage associated senescence and apoptosis via ROS-dependent p53 signalling pathway in HeLa cells

Gonolobus condurango plant extract is used as an anticancer drug in some traditional systems of medicine including homeopathy, but it apparently lacks any scientific validation. Further, no detailed study is available to suggest whether condurango-glycoside-A (CGA), a major ingredient of condurango serves as a potent anticancer compound. Therefore, we investigated apoptosis-inducing ability of CGA against cervix carcinoma cells (HeLa). β-galactosidase-activity and DNA damage were critically studied at different time points; while induced DNA-damage was observed at 9–12th hours, senescence of cells appeared at a later stage (18th hour after CGA treatment), implicating thereby a possible role of DNA damage in inducing pre-mature cell senescence. Concurrently, the number of cells undergoing apoptosis increased along with increase in reactive oxygen species (ROS) generation. Expression of p53 was also up-regulated, indicating that apoptosis could have been mediated through p53 pathway. DCHFDA (4′,6-Diamidino-2-phenylindole dihydrochloride) assay, acridine orange/ethidium bromide staining and annexin V/PI assay results collectively confirmed that apoptosis was induced by increased ROS generation. Reduction in proliferation of cells was further evidenced by the cell cycle arrest at G0/G1 stage. Expression profiles of certain relevant genes and proteins like p53, Akt, Bcl-2, Bax, cytochrome c and caspase 3 also provided evidence of ROS mediated p53 up-regulation and further boost in Bax expression and followed by cytochrome c release and activation of caspase 3. Overall results suggest that CGA initiates ROS generation, promoting up-regulation of p53 expression, thus resulting in apoptosis and pre-mature senescence associated with DNA damage.