Immobilisation of cyclodextrin glucanotransferase from <Emphasis Type="Italic">Bacillus circulans</Emphasis> ATCC 21783 on purified seasand

Cyclodextrin glucanotransferase (CGTase) from Bacillus circulans (ATCC 21783) was immobilised on a silica-based support: purified seasand. Although adsorption of 98% was achieved, considerable desorption was encountered. This problem was minimised by crosslinking the adsorbed enzyme with glutaraldehyde. The immobilised enzyme after crosslinking could be used repeatedly for cyclodextrin (CD) production in a batch process. The activity retention was 80% at the end of the eighth cycle. The immobilised enzyme showed a shift in the pH optimum towards the alkaline side and also an improvement in the pH stability compared to the free enzyme. It catalysed the formation of β-CD as a major product. A significant amount of α-CD production was also observed on prolonged incubation. Electronic Publication     

Vesicular arbuscular mycorrhizal fungi improves establishment of micropropagated Leucaena leucocephala plantlets

Investigations were carried out to achieve cent per cent transplantation success of micropropagated Leucaena leucocephala (a fast growing multipurpose leguminous tree species) plantlets using two vesicular arbuscular mycorrhizal fungi, Glomus fasciculatum and Glomus macrocarpum. Plantlets were obtained by rooting the shoots [obtained through; hypocotyl callus in presence of 10^-5M BAP + 10^-6M NAA; and axillary bud sprouting from cotyledonary and other nodes in presence of 10^-5M BAP, on Gamborg's B5 medium], on half strength B5 medium supplemented with 5×10^-6M IBA. Subsequent to the nodulation of their roots with Rhizobium (strain PRGL 001)in soilrite, these plantlets were tranferred to sterilized garden soil by laying inoculum of either Glomus fasciculatum or Glomus macrocarpum around their roots. Only 20% of the plantlets survived in soils lacking VAM fungus. In contrast, cent per cent of the plantlets of Leucaena leucocephala established very well and showed good growth in VAM inoculated soil. Roots of the later plantlets showed presence of both external and internal hyphae with well formed arbuscules and vesicles confirming the establishment of good mycorrhizal association. These studies convincingly demonstrate that the mycorrhizal association help in successful establishment of tissue culture raised plantlets of Leucaena leucocephala in the field conditions by alleviating the transplantation shock. This revised version was published online in June 2006 with corrections to the Cover Date.     

C-peptide as a Therapy for Kidney Disease: A Systematic Review and Meta-Analysis

C-peptide has intrinsic biological activity and may be renoprotective. We conducted a systematic review to determine whether C-peptide had a beneficial effect on renal outcomes. MEDLINE, EMBASE, and the Cochrane Central Databases were searched for human and animal studies in which C-peptide was administered and renal endpoints were subsequently measured. We identified 4 human trials involving 74 patients as well as 18 animal studies involving 35 separate experiments with a total of 641 animals. In humans, the renal effects of exogenously delivered C-peptide were only studied in type 1 diabetics with either normal renal function or incipient nephropathy. Pooled analysis showed no difference in GFR (mean difference, -1.36 mL/min/1.73 m2, p = 0.72) in patients receiving C-peptide compared to a control group, but two studies reported a reduction in glomerular hyperfiltration (p<0.05). Reduction in albuminuria was also reported in the C-peptide group (p<0.05). In diabetic rodent models, C-peptide led to a reduction in GFR (mean difference, -0.62 mL/min, p<0.00001) reflecting a partial reduction in glomerular hyperfiltration. C-peptide also reduced proteinuria (mean difference, -186.25 mg/day, p = 0.05), glomerular volume (p<0.00001), and mesangial matrix area (p<0.00001) in diabetic animals without affecting blood pressure or plasma glucose. Most studies were relatively short-term in duration, ranging from 1 hour to 3 months. Human studies of sufficient sample size and duration are needed to determine if the beneficial effects of C-peptide seen in animal models translate into improved long-term clinical outcomes for patients with chronic kidney disease. (PROSPERO CRD42014007472)     

Belongingness in Early Secondary School: Key Factors that Primary and Secondary Schools Need to Consider

It is unknown if, and how, students redefine their sense of school belongingness after negotiating the transition to secondary school. The current study used longitudinal data from 266 students with, and without, disabilities who negotiated the transition from 52 primary schools to 152 secondary schools. The study presents the 13 most significant personal student and contextual factors associated with belongingness in the first year of secondary school. Student perception of school belongingness was found to be stable across the transition. No variability in school belongingness due to gender, disability or household-socio-economic status (SES) was noted. Primary school belongingness accounted for 22% of the variability in secondary school belongingness. Several personal student factors (competence, coping skills) and school factors (low-level classroom task-goal orientation), which influenced belongingness in primary school, continued to influence belongingness in secondary school. In secondary school, effort-goal orientation of the student and perception of their school’s tolerance to disability were each associated with perception of school belongingness. Family factors did not influence belongingness in secondary school. Findings of the current study highlight the need for primary schools to foster belongingness among their students at an early age, and transfer students’ belongingness profiles as part of the hand-over documentation. Most of the factors that influenced school belongingness before and after the transition to secondary are amenable to change.     

Genetic Association of SNPs near ATOH7, CARD10, CDKN2B,CDC7 and SIX1/SIX6 with the Endophenotypes of Primary Open Angle Glaucoma in Indian Population

Primary open angle glaucoma (POAG) belonging to a group of optic neuropathies, result from interaction between genetic and environmental factors. Study of associations with quantitative traits (QTs) is one of the successful strategies to understand the complex genetics of POAG. The current study attempts to explore the association of variations near/in genes like ATOH7, SIX1/SIX6 complex, CDKN2B, CARD10, and CDC7 with POAG and its QTs including vertical cup to disc ratio (VCDR), central corneal thickness (CCT), intra ocular pressure (IOP), and axial length (AL). Case-control study design was carried out in a sample size of 97 POAG cases and 371 controls from South India. Model-based (additive, recessive, dominant) association of the genotypes and their interaction was carried out between cases and controls using chi-square, linear and logistic regression methods. Nominal significance (P<0.05) was observed for QTs like i) VCDR with SNPs rs1900004 (ATOH7); rs1192415 (CDC7); rs10483727 (SIX1/SIX6), rs9607469 (CARD10); ii) CCT with rs1192415; iii) IOP with rs1900004 and iv) AL with rs1900004 and rs1063192 (CDKN2B). We were able to replicate previously known interactions between ATOH7-SIX6 and SIX6-CDKN2B along with few novel interactions between ATOH7—CDC7 and SIX6 with genes including CARD10 and CDC7. In summary, our results suggest that a probable interaction among the candidate genes for QTs, play a major role in determining the individual’s susceptibility to POAG.     

Normative Database of Retinal Oximetry in Asian Indian Eyes

Objective

To study the oxygen saturation profile in normal Asian Indian eyes.

Design

A cross sectional prospective study.

Subjects

Ninety eight consecutive patients presenting to our hospital with best corrected distance visual acuity (BCVA) of 20/20 and a normal ophthalmic examination were included in the study. Patients having any ocular or systemic disease were excluded from the study.

Materials and Methods

Oximetry was performed on all subjects with the Oxymap T1 retinal oximeter (Oxymap hf, Reykjavik, Iceland).

Main Outcome Measures

The images were analysed for oxygen saturation and diameter.

Results

The mean age was 33 years (Range: 18-63; SD: 12.4). The average arteriolar saturation was 90.3 ± 6.6% and the venous saturation was 56.9% ± 6.3. The average A-V (arterio-venous) difference was 33.2% ± 5.2. There was an increase in arteriolar (R² = 0.264; p=0.001) and venous saturation (R² = 0.151; p=0.001) with age. There was no significant change in the arterio-venous saturation difference (AVSD). The inferotemporal quadrant had the lowest saturations. Age correlated positively with ocular perfusion pressure (OPP)(R² = 0.07; p=0.007). OPP correlated positively with global arteriolar saturation (R²=0.057, p=0.018).

Conclusion

This study provides the normative database for an Indian population and is comparable to previous studies. Age, vessel diameter and OPP were the significant factors that influenced the saturation. Arteriolar and venous saturations increased with age while the AVSD did not change significantly.     

Low Incidence of Renal Dysfunction among HIV-Infected Patients on a Tenofovir-Based First Line Antiretroviral Treatment Regimen in Myanmar

Background

Since 2004, Médecins Sans Frontières-Switzerland has provided treatment and care for people living with HIV in Dawei, Myanmar. Renal function is routinely monitored in patients on tenofovir (TDF)-based antiretroviral treatment (ART), and this provides an opportunity to measure incidence and risk factors for renal dysfunction.

Methods

We used routinely collected program data on all patients aged ≥15 years starting first-line TDF-based ART between January 2012 and December 2013. Creatinine clearance (CrCl) was assessed at base line and six-monthly, with renal dysfunction defined as CrCl < 50ml/min/1.73m². We calculated incidence of renal dysfunction and used Cox regression analysis to identify associated risk factors.

Results

There were 1391 patients, of whom 1372 had normal renal function at baseline. Of these, 86 (6.3%) developed renal dysfunction during a median time of follow-up 1.14 years with an incidence rate of 5.4 per 100 person-years: 78 had CrCl between 30–50ml/min/1.73m² and were maintained on TDF–based ART, but 5 were changed to another regimen: 4 because of CrCl <30ml/min/1.73m². Risk factors for renal dysfunction included age ≥45 years, diagnosed diabetes, underlying renal disease, underweight and CD4 count <200cells/mm³. There were 19 patients with baseline renal dysfunction and all continued on TDF-based ART: CrCl stayed between 30–49 ml/min/1.73m² in five patients while the remainder regained normal renal function.

Conclusions

In a resource-poor country like Myanmar, the low incidence of renal toxicity in our patient cohort suggests that routine assessment of CrCl may not be needed and could be targeted to high risk groups if resources permit.     

Spectrum of <Emphasis Type="Italic">CREBBP</Emphasis> mutations in Indian patients with Rubinstein-Taybi syndrome

Rubinstein-Taybi syndrome (RSTS), a developmental disorder comprising abnormalities that include mental retardation, an unusual facial appearance, broad thumbs and big toes is frequently associated with molecular lesions in the CREB-binding protein gene, CREBBP. The objective of the present study was to identify and analyse CREBBP mutations in Indian RSTS patients on which there are no data. Direct sequencing of CREBBP performed in 13 RSTS patients identified the three zinc fingers (CH1, CH2, CH3) and HAT domain as mutational hotspots in which ten novel pathogenic mutations were localized. Functional analysis revealed that three of these mutations affecting amino acids Glu1459, Leu1668 and Glu1724 were critical for histone acetyltransferase activity. Twenty-eight novel CREBBP single-nucleotide polymorphisms (SNPs) were also identified in the Indian population. Linkage disequilibrium studies revealed associations between (i) SNP (rs129974/c.3836-206G>C) and mutation (p.Asp1340Ala); (ii) (rs130002) with mutation (p.Asn435Lys) and (iii) SNPs rs129974, rs130002 and SNP (c.3836-206G>C) signifying a disease affection status. In conclusion, the present study reports the highest detection rate of CREBBP mutations (76.9%) in RSTS patients to date, of which ten are predicted to be pathogenic and three critical for histone acetyltransferase activity. Moreover, identification of the association of CREBBP polymorphisms with disease susceptibility could be an important risk factor for the pathogenesis of RSTS.