Identification of biomarkers for early diagnosis of diabetic nephropathy disease using direct flow through mass spectrometry.

BACKGROUND AND AIMS: Albuminuria is not an effective marker for early diagnosis of diabetic renal complication with several subjects progressing to chronic kidney disease without any albuminuria. A biomarker that can predict early changes of the diabetic kidney will be useful in effective management of type 2 diabetes. Mass spectrometry based metabolomics approach offers tremendous promise for the identification of novel metabolite biomarkers. METHODS: A case-control approach was carried out to identify renal biomarkers among Asian Indian subjects in a hospital setting. A total of 29 subjects were included in the study that included groups of diabetic controls, diabetic subjects with eGFR >90 ml/min/1.72 m2 and diabetic subjects with eGFR between 60 and 89 ml/min/1.72 m2 and eGFR between 15 and 30 ml/min/1.72 m2. We employed an un-targeted mass spectrometry method for the identification of plasma metabolites. RESULTS: A total of 1414 and 975 metabolites were identified in the positive and negative ion mode respectively. 19 metabolites were up regulated and 18 metabolites were down regulated in CKD2 and CKD4 groups when compared to control. Correlation analysis of the differential metabolites revealed Pregnenolone sulfate, creatinine and ganglioside GA1 to be negatively correlated and hexyl glucoside, all-trans-carophyll yellow and PG to be positively correlated with eGFR. CONCLUSION: We have identified Pregnenolone sulfate, GA1, PG and all-trans-Carophyll yellow as biomarkers for early identification of diabetic nephropathy. These markers could aid in better management of diabetic nephropathy that may result delaying the progression of the disease.

Molecular detection of human metapneumovirus and human bocavirus on oropharyngeal swabs collected from young children with acute respiratory tract infections from rural and peri-urban communities in South India.

BACKGROUND: Acute respiratory tract infections (ARTIs) are one of the major causes of morbidity and mortality among young children in developing countries. Information on the incidence of human metapneumovirus (hMPV) and human bocavirus (HBoV) infections in developing countries, especially among rural children, is very limited. OBJECTIVES: This study was conducted to identify whether these viruses were associated with ARTI among children ≤5 years of age in rural and peri-urban populations in South India. METHODS: The study was cross-sectional with prospective sample collection. Oropharyngeal swabs were collected from children ≤5 years of age presenting with ARTI. None of the children in this study were known to have any immunosuppressive conditions. The two viruses, hMPV and HBoV, were identified using semi-nested polymerase chain reaction (PCR) assays and one-step PCR assays, respectively. The lower limits of detection of hMPV and HBoV were 6.69 × 10(5) plasmid copies and 5.77 × 10(3) plasmid copies, respectively, per 5 µL PCR reaction input. RESULTS: The frequency of hMPV infection in children was higher than that of HBoV infection. The different frequencies of hMPV in patients in various age groups with upper and lower respiratory tract infections were compared, and the variance was found to be insignificant. In the 38 children who were hMPV positive, the majority (73.7%) were from rural communities. The overall hMPV-positive rate was higher in the rural population than in the peri-urban population, but the difference was statistically insignificant. The youngest age at which hMPV-positive status was recorded was 5 months. CONCLUSION: This study demonstrated that hMPV was associated with a significant number (i.e. >10%) of ARTIs in children in South India, whereas a relatively smaller number of HBoV infections was observed.

Analysis of sequence diversity of human metapneumovirus collected from young children with acute respiratory tract infections in South India.

BACKGROUND: Human metapneumovirus (hMPV), which has a global distribution, is an important cause of acute respiratory tract infections, especially in children and immunocompromised patients. METHODS: We investigated the genetic variability of partial nucleoprotein (N) gene sequences of hMPV strains identified among young children in South India. The sequences of the N gene were compared with previously reported sequences available in the GenBank repository. RESULTS: The results showed that strains are localized in a geographically circumscribed area (topotype). The results also demonstrates that viruses from the same genetic lineage can circulate concurrently within a given location during a given season. The close clustering of the majority of our hMPV isolates indicates that the N gene sequences in the virus population are relatively homogeneous, and suggests temporal rather than geographic variations in the evolutionary pattern. In our study, the majority of the strains belonged to genetic lineage B2 (71.1 %), followed by A2b (18.4 %), A2a (7.9 %), and B1 (2.6 %), demonstrating the presence of 4 of the 5 known genotypes of hMPV. Global alignment of the nucleotide sequences showed that the strains are closely related to sequences from Canada, The Netherlands, and Australasia. Differences at the nucleotide level and the amino acid level were identified. The results provide evidence for the diversity of the N gene of hMPV in samples collected from South India compared with global strains. When investigated for selective pressure, the sequences showed 1 positively selected site and 19 negatively selected sites. CONCLUSION: These data should prove useful in further investigations of the evolutionary dynamics of hMPV infection.