Deciphering miRNA-lncRNA-mRNA interaction through experimental validation of miRNAs, lncRNAs, and miRNA targets on mRNAs in Cajanus cajan

Pigeon pea (Cajanus cajan) is widely cultivated for its nutritional and medicinal value yet remains an orphan crop as productivity has not been improved because of a lack of genome and non-coding genome information. Non-coding RNAs, like miRNAs and long non-coding RNAs (lncRNAs), are involved in regulation of growth, metabolism, development, and stress response, and have a critical role in post-transcriptional gene regulation (PTGR). We attempted to elucidate the roles of miRNAs and lncRNAs in pigeon pea through experimental validation of computationally predicted miRNAs and lncRNAs and targets of miRNAs on mRNAs. We experimentally validated 20 miRNAs and 11 lncRNAs. We predicted cleavage sites of three miRNA targets: serine/threonine-protein kinase, polygalacturonase, beta-galactosidase. We identified 469 targets of 265 miRNAs and their functional annotations using computational methods. We built a miRNA-mRNA-lncRNA network model, with the miRNAs targeting both mRNAs and lncRNAs, to obtain information on the interplay of these three molecules. A confirmed interaction through experimental validation was established between miRNA, namely cca-miR1535a targeting the mRNA for beta-galactosidase, as well as the lncRNA cca-lnc-020033. Our findings increase knowledge of the non-coding genome of pigeon pea and their roles in PTGR and in improving agronomic traits of this pulse crop.

Understanding the Acceptability of Broadly Neutralizing Antibodies for HIV Prevention Among At-Risk Populations and Feasibility Considerations for Product Introduction in India: Protocol for a Qualitative Study

BACKGROUND

Acceptability and preference research play a crucial role in the design, evaluation, and implementation of any new prevention product in any geographical setting. They also play a critical role in the development of clinical guidelines and policies. A wide range of acceptability studies have been conducted in diverse general and key populations for various new HIV prevention products worldwide. As clinical development strategies are being developed for clinical studies of broadly neutralizing antibodies (bNAbs) as potential HIV prevention products, appropriately tailoring them to address the type of HIV epidemic at hand would be critical for efficient uptake within in-country public health systems and decrease adoption and adherence challenges. Accomplishing this will require comprehensive acceptability and feasibility studies to inform multisectoral efforts that increase access to these products and national policies supportive of access to health care for those in most need. Thus, it is both opportune and important to undertake focused efforts toward informing product development strategies.

OBJECTIVE

This study aims to understand preferences for product attributes and key behavioral factors influencing adoption and uptake of bNAb prevention products among end-users including female sex workers, men who have sex with men, transgender women, people who inject drugs, and adolescent girls and young women in India and understand the key health system and programmatic perspectives toward the introduction of bNAb prevention products from health service providers and policy makers in India.

METHODS

A multisite study will be conducted in Delhi, Mumbai, and Chennai to capture the differences in perspectives among diverse end-users and key informants across the country. The study will use a multimethods design using focus group discussions, in-depth interviews, simulated behavioral experiments, and key informant interviews. A total of 30 focus group discussions, 45 in-depth interviews, 15 simulated behavioral experiments sessions, and 15 key informant interviews will be conducted across 3 sites.

RESULTS

The data collected and analyzed will enable insights on which specific product attributes matter the most to the populations and why some attributes are less preferred; contextual drivers of preferences and choices at individual, interpersonal, social, and structural levels; and relative positioning of bNAb products among other potential HIV prevention products. Insights from the health service providers and policy makers will provide a critical understanding of the need perception of the potential product in the existing product landscape and what additional efforts and resources are required for potential introduction, delivery, and uptake of the bNAb products in the Indian context.

CONCLUSIONS

Insights generated from the abovementioned objectives will represent perspectives of populations of interest across geographies in India, will provide an overview of the acceptability of bNAb products and the feasibility of their introduction in this region, and will inform product development strategies.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/47700.

Engagement of vulnerable communities in HIV prevention research in India: a qualitative investigation

BACKGROUND

Meaningful community engagement (CE) in HIV prevention research is crucial for successful and ethically robust study implementation. We conducted a qualitative study to understand the current CE practices in HIV prevention research and to identify expressed and implicit reasons behind translational gaps highlighted by communities and researchers.

METHODS

For this exploratory qualitative study, we recruited a purposive sample of participants from Indian government-recognised key populations such as men who have sex with men, transgender women, people who inject drugs and female sex workers; general population adults and adolescents/youth; and researchers. We conducted 13 virtual focus groups (n = 86) between July and October 2021. Data were explored from a critical realist perspective and framing analysis (i.e., examining how the participants framed the narratives).

RESULTS

Participants reported that study communities, especially those from key populations, were primarily involved in data collection, but not necessarily with optimal training. Involvement of communities before the start of the study (e.g., obtaining feedback on the study's purpose/design) or once the study is completed (e.g., sharing of findings) were highlighted as priorities for meaningful engagement. Participants suggested meaningful CE in all stages of the study: (1) before the study-to get inputs in finalising the study design, drafting comprehensible informed consent forms and culturally-appropriate data collection tools, and deciding on appropriate monetary compensation; (2) during the study-adequate training of community field research staff; and (3) after the study-sharing the draft findings to get community inputs, and involving communities in advocacy activities towards converting evidence into action, policy or programs. Timely and transparent communications with communities were explicitly stated as critical for gaining and maintaining trust. Mutual respect, reciprocity (e.g., appropriate monetary compensation) and robust community feedback mechanisms were considered critical for meaningful CE.

CONCLUSIONS

The findings highlighted the translational gaps and priority areas for capacity building to strengthen CE in HIV prevention research. It is not only important to engage communities at various stages of research but to understand that trust, dignity, respect, and reciprocity are fundamentally preferred ways of meaningful community engagement.

Assessment of data intelligence algorithms in modeling daily reference evapotranspiration under input data limitation scenarios in semi-arid climatic condition

Crop evapotranspiration is essential for planning and designing an efficient irrigation system. The present investigation assessed the capability of four machine learning algorithms, namely, XGBoost linear regression (XGBoost Linear), XGBoost Ensemble Tree, Polynomial Regression (Polynomial Regr), and Isotonic Regression (Isotonic Regr) in modeling daily reference evapotranspiration (ET_o) at IARI, New Delhi. The models were developed considering full and limited dataset scenarios. The efficacy of the constructed models was assessed against the Penman-Monteith (PM56) model estimated daily ET_o. Results revealed the under full and limited dataset conditions, XGBoost Ensemble Tree gave the best results for daily ET_o modeling during the model training period, while in the testing period under scenarios S1(T_max) and S2 (T_max, and T_min), the Isotonic Regr models yielded superior results over other models. In addition, the XGBoost Ensemble Tree models outperformed others for the rest of the input data scenarios. The XGBoost Ensemble Tree algorithms reported the best values of correlation coefficient (r), mean absolute error (MAE), mean square error (MSE), root mean square error (RMSE), and mean absolute percentage error (MAPE). Thus, we recommend applying the XGBoost Ensemble Tree algorithm for precisely modeling daily ET_o in semi-arid climatic conditions.

P15.02 Loss of Williams Syndrome Transcription Factor (WSTF) leads to improved temozolomide sensitivity in human glioblastoma cells irrespective of MGMT expression

BACKGROUND

The prognosis for newly diagnosed adult glioblastoma multiforme (GBM) patients is poor even after standard therapy with a median survival of approximately 14–15 months. The DNA repair protein O 6 -methylguanine-DNA methyltransferase (MGMT) efficiently counteracts formation of the most lethal DNA adducts by temozolomide (TMZ) chemotherapy, and is thus associated with poor outcome in GBM patients. Williams Syndrome Transcription Factor (WSTF) has previously been suggested to regulate the DNA damage response pathway (DDR) in both an indirect (through chromatin remodeling together with SMARCA5 in the WICH complex) and direct manner (by phosphorylating H2AX at Tyr142). However, whether WSTF has any role in the development of resistance against chemotherapy through its ability to regulate the DDR in GBMs, is so far not known. In this study, we investigated whether loss of WSTF sensitizes different MGMT-proficient and -deficient GBM cell lines to TMZ treatment.

MATERIAL AND METHODS

We generated WSTF knockout clones from both MGMT-proficient (LN18, T98G) and -deficient GBM cell lines (U-251) using CRISPR/Cas9 gene-editing technology with lentiviral vectors. The PCR-based screening results combined with the T7 endonuclease mismatch assay for bi-allelic monoclonal knockouts were verified via sequencing and immunoblotting to identify candidate knockout clones. For each cell line, three knockout clones were chosen for further investigation. Colony formation assays were performed to determine the survival ability in response to TMZ treatment. Statistical analysis was performed using two-way ANOVA.

RESULTS

WSTF knockout clones showed a significant decrease in colony formation after TMZ-treatment compared to the corresponding WSTF-expressing control groups (non-target single guide RNA) (LN18: Clone 59 vs control: p= 0.0456, T98G: All three studied clones vs control: p <0.0001, U-251: Clone 7/35.1/70.2 vs control: p <0.0001/p= 0.0107/p= 0.0119). Furthermore, two out of three clones of T98G and U-251 (T98G Clone 13 and 128 vs control, p <0.0001, U-251 Clone 7 vs control, p= 0.0062; clone 70.2, p= 0.0052) showed significantly reduced plating efficiency compared to control cells.

CONCLUSION

WSTF is an important factor in both MGMT de- and proficient GBM cell lines for response against TMZ chemotherapy. The loss of WSTF leads to a significantly increased TMZ sensitivity in clinically relevant concentrations for all the studied cell lines. Ongoing studies are investigating the underlying mechanisms and potential alterations in the DDR pathway caused by WSTF loss.

Nickel Ferrite Nanoparticles as an Adsorbent for Immobilized Metal Affinity Chromatography of Proteins

A simple method of preparing amorphous nickel ferrite nanoparticles of about 5 nm diameter is described. These particles were characterized by dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM) and selected area electron diffraction (SAED). The nanoparticles were evaluated for their use as a magnetic material for immobilized metal affinity chromatography (IMAC). The ferrite nanoparticles bound to bovine serum albumin (BSA) and the binding fitted Langmuir isotherm model. A high capacity of 916 mg BSA/g dried nanoparticle was observed. Six proteins (Soybean trypsin inhibitor (STI), lactate dehydrogenase (LDH), papain, catalase, β-galactosidase and casein) were used and all were found to bind at >90% level (except papain which showed 84% binding). All the proteins except LDH and β-galactosidase could be eluted with 1 M imidazole and with % activity recovery of >80%. Papain could be purified from its dried crude latex by 5-fold and purified papain showed a single band on SDS-PAGE. These nanoparticles constitute a high capacity and are magnetic material useful for IMAC and do not require any pre-functionalization.

Characteristics of Minor Ions and Electrons in Flux Transfer Events Observed by the Magnetospheric Multiscale Mission

In this study, the ion composition of flux transfer events (FTEs) observed within the magnetosheath proper is examined. These FTEs were observed just upstream of the Earth's postnoon magnetopause by the National Aeronautics and Space Administration (NASA) Magnetospheric Multiscale (MMS) spacecraft constellation. The minor ion characteristics are described using energy spectrograms, flux distributions, and ion moments as the constellation encountered each FTE. In conjunction with electron data and magnetic field observations, such observations provide important contextual information on the formation, topologies, and evolution of FTEs. In particular, minor ions, when combined with the field-aligned streaming of electrons, are reliable indicators of FTE topology. The observations are also placed (i) in context of the solar wind magnetic field configuration, (ii) the connection of the sampled flux tube to the ionosphere, and (iii) the location relative to the modeled reconnection line at the magnetopause. While protons and alpha particles were often depleted within the FTEs relative to the surrounding magnetosheath plasma, the He+ and O+ populations showed clear enhancements either near the center or near the edges of the FTE, and the bulk plasma flow directions are consistent with magnetic reconnection northward of the spacecraft and convection from the dayside toward the flank magnetopause.

Association of circulatory Tfh-like cells with neutralizing antibody responses among chronic HIV-1 subtype C infected long-term nonprogressors and progressors

HIV-1 vaccine functioning relies on successful induction of broadly neutralizing antibodies (bNAbs). CXCR3- circulatory T-follicular helper (cTfh) cells are necessary for inducing B-cells for generating bNAbs. Recent studies have suggested that CXCR3+ Tfh cells might also influence bNAb production. Plasma samples from 34 ART-Naïve HIV-1 infected individuals [long-term nonprogressors (LTNP)-19; Progressors-13] were tested against a heterologous virus panel (n = 11) from subtypes A, B, C, G, AC, BC and AE. Frequencies of CXCR3+ and CXCR3- cTfh-like cells in peripheral circulation were studied using flow cytometry. LTNP showed significantly lower CXCR3+ and higher CXCR3- cTfh-like cell frequencies, while neutralization breadth was observed to be broader in progressors. A positive correlation was observed between bNAb breadth and potency with CXCR3+PD-1+ cTfh-like cells in LTNP. Based on neutralization breadth, 9 HIV-1 infected individuals were classified as 'top neutralizers' and 23 as 'low neutralizers' and they did not show any correlations with CXCR3+ and CXCR3- cTfh-like cells. These preliminary data suggest that CXCR3+ similar to CXCR3- might possess significant functional properties for driving B-cells to produce bNAbs. Hence, an HIV vaccine which is capable of optimal induction of CXCR3+ cTfh cells at germinal centers might confer superior protection against HIV.

Evaluation of antiviral T cell responses and TSCM cells in volunteers enrolled in a phase I HIV-1 subtype C prophylactic vaccine trial in India

T cells play an important role in controlling viral replication during HIV infection. An effective vaccine should, therefore, lead to the induction of a strong and early viral-specific CD8⁺ T cell response. While polyfunctional T cell responses are thought to be important contributors to the antiviral response, there is evidence to show that polyfunctional HIV- specific CD8⁺ T cells are just a small fraction of the total HIV-specific CD8⁺ T cells and may be absent in many individuals who control HIV replication, suggesting that other HIV-1 specific CD8⁺ effector T cell subsets may be key players in HIV control. Stem cell-like memory T cells (T_SCM) are a subset of T cells with a long half-life and self-renewal capacity. They serve as key reservoirs for HIV and contribute a significant barrier to HIV eradication. The present study evaluated vaccine-induced antiviral responses and T_SCM cells in volunteers vaccinated with a subtype C prophylactic HIV-1 vaccine candidate administered in a prime-boost regimen. We found that ADVAX DNA prime followed by MVA boost induced significantly more peripheral CD8⁺ T_SCM cells and higher levels of CD8⁺ T cell-mediated inhibition of replication of different HIV-1 clades as compared to MVA alone and placebo. These findings are novel and provide encouraging evidence to demonstrate the induction of T_SCM and cytotoxic immune responses by a subtype C HIV-1 prophylactic vaccine administered using a prime-boost strategy.

Induction and maintenance of bi-functional (IFN-γ + IL-2+ and IL-2+ TNF-α+) T cell responses by DNA prime MVA boosted subtype C prophylactic vaccine tested in a Phase I trial in India

Effective vaccine design relies on accurate knowledge of protection against a pathogen, so as to be able to induce relevant and effective protective responses against it. An ideal Human Immunodeficiency virus (HIV) vaccine should induce humoral as well as cellular immune responses to prevent initial infection of host cells or limit early events of viral dissemination. A Phase I HIV-1 prophylactic vaccine trial sponsored by the International AIDS Vaccine Initiative (IAVI) was conducted in India in 2009.The trial tested a HIV-1 subtype C vaccine in a prime-boost regimen, comprising of a DNA prime (ADVAX) and Modified Vaccine Ankara (MVA) (TBC-M4) boost. The trial reported that the vaccine regimen was safe, well tolerated, and resulted in enhancement of HIV-specific immune responses. However, preliminary immunological studies were limited to vaccine-induced IFN-γ responses against the Env and Gag peptides. The present study is a retrospective study to characterize in detail the nature of the vaccine-induced cell mediated immune responses among volunteers, using Peripheral Blood Mononuclear Cells (PBMC) that were archived during the trial. ELISpot was used to measure IFN-γ responses and polyfunctional T cells were analyzed by intracellular multicolor flow cytometry. It was observed that DNA priming and MVA boosting induced Env and Gag specific bi-functional and multi-functional CD4⁺ and CD8⁺ T cells expressing IFN-γ, TNF-α and IL-2. The heterologous prime-boost regimen appeared to be slightly superior to the homologous prime-boost regimen in inducing favorable cell mediated immune responses. These results suggest that an in-depth analysis of vaccine-induced cellular immune response can aid in the identification of correlates of an effective immunogenic response, and inform future design of HIV vaccines.

Induction of circulating T follicular helper cells and regulatory T cells correlating with HIV-1 gp120 variable loop antibodies by a subtype C prophylactic vaccine tested in a Phase I trial in India

A Phase I HIV-1 vaccine trial sponsored by the International AIDS Vaccine Initiative (IAVI) was conducted in India in 2009 to test a subtype C prophylactic vaccine in a prime-boost regimen comprising of a DNA prime (ADVAX) and MVA (TBC-M4) boost. The trial demonstrated that the regimen was safe and well tolerated and resulted in enhancement of HIV-specific immune responses. Preliminary observations on vaccine-induced immune responses were limited to analysis of neutralizing antibodies and IFN-γ ELISPOT response. The present study involves a more detailed analysis of the nature of the vaccine-induced humoral immune response using specimens that were archived from the volunteers at the time of the trial. Interestingly, we found vaccine induced production of V1/V2 and V3 region-specific antibodies in a significant proportion of vaccinees. Variable region antibody levels correlated directly with the frequency of circulating T follicular helper cells (Tfh) and regulatory T cells (Treg). Our findings provide encouraging evidence to demonstrate the immunogenicity of the tested vaccine. Better insights into vaccine-induced immune responses can aid in informing future design of a successfulHIV-1 vaccine.

Broad neutralization response in a subset of HIV-1 subtype C-infected viraemic non-progressors from southern India

Broadly neutralizing antibodies (bnAbs) have been considered to be potent therapeutic tools and potential vaccine candidates to enable protection against various clades of human immunodeficiency virus (HIV). The generation of bnAbs has been associated with enhanced exposure to antigen, high viral load and low CD4+ T cell counts, among other factors. However, only limited data are available on the generation of bnAbs in viraemic non-progressors that demonstrate moderate to high viraemia. Further, since HIV-1 subtype C viruses account for more than 50 % of global HIV infections, the identification of bnAbs with novel specificities is crucial to enable the development of potent tools to aid in HIV therapy and prevention. In the present study, we analysed and compared the neutralization potential of responses in 70 plasma samples isolated from ART-naïve HIV-1 subtype C-infected individuals with various disease progression profiles against a panel of 30 pseudoviruses. Among the seven samples that exhibited a neutralization breadth of ≥70 %, four were identified as 'elite neutralizers', and three of these were from viraemic non-progressors while the fourth was from a typical progressor. Analysis of the neutralization specificities revealed that none of the four elite neutralizers were reactive to epitopes in the membrane proximal external region (MPER), CD4-binding site and V1V2 or V3 glycan. However, two of the four elite neutralizers exhibited enhanced sensitivity towards viruses lacking N332 glycan, indicating high neutralization potency. Overall, our findings indicate that the identification of potent neutralization responses with distinct epitope specificities is possible from the as yet unexplored Indian population, which has a high prevalence of HIV-1 subtype C infection.

Perennial occurrence of heterotrophic, indicator and pathogenic bacteria in the coastal Bay of Bengal (off Visakhapatnam) - Impact of physical and atmospheric processes

In order to examine the health of the coastal waters off Visakhapatnam in terms of prevalence and abundance of heterotrophic (H), indicator and pathogenic (P) bacterial counts (BC) and influence of physical processes on them, time-series observations were conducted during January (winter), March (spring), July (summer) and October (post-monsoon). We noticed the impact of physical forces on substantial variations in abundance and distribution of the HBC, total coliforms, Enterococcus faecalis and Pseudomonas aeruginosa in the study region. Based on our results Escherichia coli and other PBC were not much influenced by the physical conditions. It has been noticed that the perennial existence of the high abundance of IBC and PBC above the standard limits during the entire study period leading to an alarming situation in the coastal waters off Visakhapatnam.

Cross-Linked Enzyme Aggregates for Applications in Aqueous and Nonaqueous Media

Extensive cross-linking of a precipitate of a protein by a cross-linking reagent (glutaraldehyde has been most commonly used) creates an insoluble enzyme preparation called cross-linked enzyme aggregates (CLEAs). CLEAs show high stability and performance in conventional aqueous as well as nonaqueous media. These are also stable at fairly high temperatures. CLEAs with more than one kind of enzyme activity can be prepared, and such CLEAs are called combi-CLEAs or multipurpose CLEAs. Extent of cross-linking often influences their morphology, stability, activity, and enantioselectivity.

Protein-Coated Microcrystals, Combi-Protein-Coated Microcrystals, and Cross-Linked Protein-Coated Microcrystals of Enzymes for Use in Low-Water Media

Protein-coated microcrystals (PCMC) are a high-activity preparation of enzymes for use in low-water media. The protocols for the preparation of PCMCs of Subtilisin Carlsberg and Candida antarctica lipase B (CAL B) are described. The combi-PCMC concept is useful both for cascade and non-cascade reactions. It can also be beneficial to combine two different specificities of a lipase when the substrate requires it. Combi-PCMC of CALB and Palatase used for the conversion of coffee oil present in spent coffee grounds to biodiesel is described. Cross-linked protein-coated microcrystals (CL-PCMC) in some cases can give better results than PCMC. Protocols for the CLPCMC of Subtilisin Carlsberg and Candida antarctica lipase B (CAL B) are described. A discussion of their applications is also provided.

The impact of user fees on health services utilization and infectious disease diagnoses in Neno District, Malawi: a longitudinal, quasi-experimental study

Background

User fees have generally fallen out of favor across Africa, and they have been associated with reductions in access to healthcare. We examined the effects of the introduction and removal of user fees on outpatient attendances and new diagnoses of HIV, malaria, and tuberculosis in Neno District, Malawi where user fees were re-instated at three of 13 health centres in 2013 and subsequently removed at one of these in 2015.

Methods

We conducted two analyses. Firstly, an unadjusted comparison of outpatient visits and new diagnoses over three periods between July 2012 and October 2015: during the period with no user fees, at the re-introduction of user fees at four centres, and after the removal of user fees at one centre. Secondly, we estimated a linear model of the effect of user fees on the outcome of interest that controlled for unobserved health centre effects, monthly effects, and a linear time trend.

Results

The introduction of user fees was associated with a change in total attendances of −68 % [95 % CI: −89 %, −12 %], similar reductions were observed for new malaria and HIV diagnoses. The removal of user fees was associated with an increase in total attendances of 352 % [213 %, 554 %] with similar increases for malaria diagnoses. The results were not sensitive to control group or model specification.

Conclusions

User fees for outpatient healthcare services present a barrier to patients accessing healthcare and reduce detection of serious infectious diseases.

Electronic supplementary material

The online version of this article (doi:10.1186/s12913-016-1856-x) contains supplementary material, which is available to authorized users.

Lipase coated clusters of iron oxide nanoparticles for biodiesel synthesis in a solvent free medium

Methyl or ethyl esters of long chain fatty acids are called biodiesel. Biodiesel is synthesized by the alcoholysis of oils/fats. In this work, lipase from Thermomyces lanuginosus was precipitated over the clusters of Fe3O4 nanoparticles. This biocatalyst preparation was used for obtaining biodiesel from soybean oil. After optimization of both immobilization conditions and process parameters, complete conversion to biodiesel was obtained in 3h and on lowering the enzyme amount, as little as 1.7U of lipase gave 96% conversion in 7h. The solvent free media with oil:ethanol (w/w) of 1:4 and 40°C with 2% (w/w) water along with 20% (w/w) silica (for facilitating acyl migration) were employed for reaching this high % of conversion. The biocatalyst design enables one to use a rather small amount of lipase. This should help in switching over to a biobased production of biodiesel.

Network meta-analysis of treatments for type 2 diabetes mellitus following failure with metformin plus sulfonylurea

Aims The efficacy and safety of sodium-glucose linked transporters (SGLT2s) plus metformin and a sulfonylurea (MET + SU) for the treatment of type 2 diabetes mellitus (T2DM) in patients who fail to achieve glycemic control with MET + SU, relative to other triple therapies licensed in the EU, were estimated. Methods A systematic literature review and network meta-analysis (NMA) of randomized controlled trials (RCTs) involving anti-diabetes treatments added to MET + SU were conducted.

RESULTS

Of 2236 abstracts identified through a systematic literature review, 30 RCTs published between 2003 and 2013 were included. RCTs ranged from 12 to 52 weeks in duration, included 28 to 1274 patients, were of parallel design, and most were open-label. Comparators included placebo (reference treatment), SGLT2 inhibitors, dipeptidyl peptidase-4 (DPP-4) inhibitors, thiazolidinediones (TZDs), alpha-glucosidase inhibitors (AGIs), meglitinides, glucagon-like peptide 1 (GLP-1) analogues, and basal, bolus, and biphasic insulin, all added on to MET + SU, as well as basal and biphasic insulin added to MET and monotherapy. The mean change (%) in HbA1c levels compared to placebo was -0.86 for SGLT2 inhibitors, -0.68 for DPP-4 inhibitors, -0.93 for TZDs, and -1.07 for GLP-1 analogues, respectively. Only SGLT2 inhibitors and GLP-1 analogues led to a weight loss (-1.71 kg and -1.14 kg, respectively) and decrease in systolic blood pressure (SBP; -3.73 mmHg and -2.90 mmHg, respectively), while all other treatments showed either an increase or no changes in weight or SBP. Conclusion SGLT2 inhibitors are at least as effective as other classes of antidiabetic agents at controlling HbA1c levels, while providing the additional benefits of weight loss and reducing SBP. Additionally, since the risk of hypoglycemia is similar or reduced with SGLT2 inhibitors, patients do not have to trade off efficacy for tolerability. Similar findings were observed for GLP-1 analogues.

Molecular bioimprinting of lipases with surfactants and its functional consequences in low water media

Lipases from Thermomyces lanuginosa (TLL), Candida rugosa (CRL) and Burkholderia cepacia (BCL) were obtained in the 'open lid' form by adding surfactant molecules like n-octyl-β-d-glucopyranoside (OG), hexadecyl trimethyl ammonium bromide (CTAB), Bis(2-ethylhexyl) sulfosuccinate sodium salt (AOT) and triton X-100 for this purpose. The enzymes were 'dried' by precipitating with 4× (v/v) excess of organic solvents. The imprint surfactant molecules were removed by extensive washing with organic solvents. TLL imprinted with 0.05% CTAB showed 11-fold increase in the transesterification activity and was a better preparation to kinetically resolve (±)-1-phenylethanol. Fluorescence emission spectra confirmed that Trp89 of the lid was indeed affected during bioimprinting. With CRL, bioimprinting with OG gave 7-fold increase in the transesterification rates and resulted in reversal of enantioselectivity of CRL and gave R-phenylethyl acetate instead of the S-product as with the unimprinted precipitate. Bioimprinted BCL was also a 7-fold better catalyst for transesterification as well as enantioselectivity.

The family 6 Carbohydrate Binding Module (CtCBM6) of glucuronoxylanase (CtXynGH30) of Clostridium thermocellum binds decorated and undecorated xylans through cleft A

CtCBM6 of glucuronoxylan-xylanohydrolase (CtXynGH30) from Clostridium thermocellum was cloned, expressed and purified as a soluble ~14 kDa protein. Quantitative binding analysis with soluble polysaccharides by affinity electrophoresis and ITC revealed that CtCBM6 displays similar affinity towards decorated and undecorated xylans by binding wheat- and rye-arabinoxylans, beechwood-, birchwood- and oatspelt-xylan. Protein melting studies confirmed thermostable nature of CtCBM6 and that Ca(2+) ions did not affect its structure stability and binding affinity significantly. The CtCBM6 structure was modeled and refined and CD spectrum displayed 44% β-strands supporting the predicted structure. CtCBM6 displays a jelly roll β-sandwich fold presenting two potential carbohydrate binding clefts, A and B. The cleft A, is located between two loops connecting β4-β5 and β8-β9 strands. Tyr28 and Phe84 present on these loops make a planar hydrophobic binding surface to accommodate sugar ring of ligand. The cleft B, is located on concave surface of β-sandwich fold. Tyr34 and Tyr104 make a planar hydrophobic platform, which may be inaccessible to ligand due to hindrance by Pro68. Site-directed mutagenesis revealed Tyr28 and Phe84 in cleft A, playing a major role in ligand binding. The results suggest that CtCBM6 interacts with carbohydrates through cleft A, which recognizes equally well both decorated and un-decorated xylans.

Increasing importance of protein flexibility in designing biocatalytic processes

Enzymes require some flexibility for catalysis. Biotechnologists prefer stable enzymes but often this stabilization comes at the cost of reduced efficiency. Enzymes from thermophiles have low flexibility but poor catalytic rates. Enzymes from psychrophiles are less stable but show good catalytic rates at low temperature. In organic solvents enzymes perform poorly as the prior drying makes the enzyme molecules very rigid. Adding water or increasing reaction temperature improves flexibility and catalytic rates. In case of hydrolases, flexibility and enantioselectivity have interdependence. Understanding the complex role of protein flexibility in biocatalysis can help in designing biotechnological processes.

Enzyme promiscuity: using the dark side of enzyme specificity in white biotechnology

Enzyme promiscuity can be classified into substrate promiscuity, condition promiscuity and catalytic promiscuity. Enzyme promiscuity results in far larger ranges of organic compounds which can be obtained by biocatalysis. While early examples mostly involved use of lipases, more recent literature shows that catalytic promiscuity occurs more widely and many other classes of enzymes can be used to obtain diverse kinds of molecules. This is of immense relevance in the context of white biotechnology as enzyme catalysed reactions use greener conditions.

Determinants of glycaemic control in a practice setting: the role of weight loss and treatment adherence (The DELTA Study)

AIMS

Examine the association between weight loss and adherence with glycaemic goal attainment in patients with inadequately controlled T2DM.

MATERIALS AND METHODS

Patients ≥ 18 years with T2DM from a US integrated health system starting a new class of diabetes medication between 11/1/10 and 4/30/11 (index date) with baseline HbA1c ≥ 7.0% were included in this cohort study. Target HbA1c and weight change were defined at 6-months as HbA1c < 7.0% and ≥ 3% loss in body weight. Patient-reported medication adherence was assessed per the Medication Adherence Reporting Scale. Structural equation modelling was used to describe simultaneous associations between adherence, weight loss and HbA1c goal attainment.

RESULTS

Inclusion criteria were met by 477 patients; mean (SD) age 59.1 (11.6) years; 50.9% were female; 30.4% were treatment naïve; baseline HbA1c 8.6% (1.6); weight 102.0 kg (23.0). Most patients (67.9%) reported being adherent to the index diabetes medication. At 6 months mean weight change was -1.3 (5.1) kg (p = 0.39); 28.1% had weight loss of ≥ 3%. Mean HbA1c change was -1.2% (1.8) (p< 0.001); 42.8% attained HbA1c goal. Adherent patients (OR 1.70; p = 0.02) and diabetes therapies that lead to weight loss (metformin, GLP-1) were associated with weight loss ≥ 3% (OR 2.96; p< 0.001). Weight loss (OR 3.60; p < 0.001) and adherence (OR 1.59; p < 0.001) were associated with HbA1c goal attainment.

CONCLUSIONS

Weight loss ≥ 3% and medication adherence were associated with HbA1c goal attainment in T2DM; weight loss was a stronger predictor of goal attainment than medication adherence in this study population. It is important to consider weight-effect properties, in addition to patient-centric adherence counselling, when prescribing diabetes therapy.

Can people with type 2 diabetes live longer than those without? A comparison of mortality in people initiated with metformin or sulphonylurea monotherapy and matched, non-diabetic controls

AIMS

Clinical and observational studies have shown an increased risk of cardiovascular events and death associated with sulphonylureas versus metformin. However, it has never been determined whether this was due to the beneficial effects of metformin or detrimental effects of sulphonylureas. The objective of this study was therefore to compare all-cause mortality in diabetic patients treated first-line with either sulphonylurea or metformin monotherapy with that in matched individuals without diabetes.

METHODS

We used retrospective observational data from the UK Clinical Practice Research Datalink (CPRD) from 2000. Subjects with type 2 diabetes who progressed to first-line treatment with metformin or sulphonylurea monotherapy were selected and matched to people without diabetes. Progression to all-cause mortality was compared using parametric survival models that included a range of relevant co-variables.

RESULTS

We identified 78,241 subjects treated with metformin, 12,222 treated with sulphonylurea, and 90,463 matched subjects without diabetes. This resulted in a total, censored follow-up period of 503,384 years. There were 7498 deaths in total, representing unadjusted mortality rates of 14.4 and 15.2, and 50.9 and 28.7 deaths per 1000 person-years for metformin monotherapy and their matched controls, and sulphonylurea monotherapy and their matched controls, respectively. With reference to observed survival in diabetic patients initiated with metformin monotherapy [survival time ratio (STR) = 1.0], adjusted median survival time was 15% lower (STR = 0.85, 95% CI 0.81-0.90) in matched individuals without diabetes and 38% lower (0.62, 0.58-0.66) in diabetic patients treated with sulphonylurea monotherapy.

CONCLUSIONS

Patients with type 2 diabetes initiated with metformin monotherapy had longer survival than did matched, non-diabetic controls. Those treated with sulphonylurea had markedly reduced survival compared with both matched controls and those receiving metformin monotherapy. This supports the position of metformin as first-line therapy and implies that metformin may confer benefit in non-diabetes. Sulphonylurea remains a concern.

Association between first-line monotherapy with sulphonylurea versus metformin and risk of all-cause mortality and cardiovascular events: a retrospective, observational study

AIMS

To evaluate the risk of all-cause mortality and major adverse cardiovascular events (MACE) for patients exposed to first-line monotherapy with sulphonylurea or metformin.

METHODS

Data were from the Clinical Practice Research Datalink (CPRD). Patients with type 2 diabetes were selected if initiated with metformin or sulphonylurea monotherapy as their first-line glucose-lowering regimen 2000-2012. The primary endpoint was all-cause mortality; the secondary endpoint was MACE (myocardial infarction or stroke). Times to endpoints were compared using Cox proportional hazards models. Additional analyses were performed on subsets matched directly on key characteristics and by propensity score.

RESULTS

In the main analysis, 76 811 patients were prescribed metformin monotherapy (mean follow-up 2.9 years) and 15 687 sulphonylurea monotherapy (mean follow-up 3.1 years). A total of 2604 patients were included in each arm of the directly matched cohorts and 8836 in the propensity-matched. With respect to all-cause mortality, using all three analytical approaches the hazard ratio (HR) was significantly increased for sulphonylurea compared with metformin: adjusted HR = 1.580 (95% CI 1.483-1.684) for the main analysis, 1.902 (1.733-2.088) for those matched on propensity score, and 1.272 (1.021-1.584) for the directly matched cohort analysis. For MACE, the respective HRs were 1.196 (1.090-1.313), 1.202 (1.001-1.442) and 0.814 (0.578-1.148), respectively.

CONCLUSIONS

All-cause mortality was significantly increased in patients prescribed sulphonylurea compared with metformin monotherapy. Whilst residual confounding and confounding by indication may remain, this study indicates that first-line treatment with sulphonylurea monotherapy should be reconsidered.

Combination therapy with metformin plus sulphonylureas versus metformin plus DPP-4 inhibitors: association with major adverse cardiovascular events and all-cause mortality

AIMS

To compare the risk of major adverse cardiovascular events (MACE) and mortality for combination therapies with metformin and either sulphonylurea (SU) or dipeptidyl peptidase-4 inhibitor (DPP-4i).

METHODS

Data were from the UK Clinical Practice Research Datalink (CPRD). Patients with type 2 diabetes were selected if initiated with combination therapies comprising metformin plus SU or DPP-4i 2007-2012. The co-primary endpoints were all-cause mortality and MACE (myocardial infarction or stroke). Times to endpoints were compared using Cox proportional hazards models. Additional analyses were performed on subsets matched directly on key characteristics and by propensity score.

RESULTS

A total of 33 983 patients were prescribed SU and 7864 DPP-4i, and 5447 patients in each cohort could be matched directly and 6901 by propensity score. In the main analysis, there were 716 MACE events and 1217 deaths. Crude event rates for MACE were 11.3 events per 1000 person-years (pkpy) for SU, versus 5.3 pkpy for DPP-4i. For all-cause mortality, rates were 16.9 versus 7.3 pkpy, respectively. Following adjustment, there was a significant increase in the adjusted hazard ratio (aHR) for all-cause mortality in those exposed to SU across all analytical models: aHR = 1.357 (95% CI 1.076-1.710) for all subjects, 1.850 (1.245-2.749) directly matched and 1.497 (1.092-2.052) propensity-matched. For MACE, aHR was 1.710 (1.280-2.285) for all subjects, 1.323 (0.832-2.105) directly matched and 1.547 (1.076-2.225) propensity-matched.

CONCLUSIONS

There was a reduction in all-cause mortality for patients treated with metformin combined with DPP-4i versus metformin plus SU, and a similar trend for MACE.

Lipase catalyzed transesterification of castor oil by straight chain higher alcohols

Biolubricants from Castor oil were produced enzymatically by transesterification with higher alcohols using a lipase mixture of immobilized Mucor miehei (RMIM) and immobilized Candida antarctica lipase B (Novozym 435) under low water conditions. The conversions were in the range of 80-95% under the optimized conditions.

The impact on utilities of differences in body weight among Canadian patients with type 2 diabetes

OBJECTIVE

The objective of this study was to estimate utility values for hypothetical health states that describe differences in weight and quality of life associated with type 2 diabetes mellitus (DM) from Canadians with type 2 DM. The impact on utility values was examined separately for participants with a body mass index (BMI) of 18 to less than 25 kg/m(2) ('healthy'), 25 to less than 30 ('overweight'), and 30 or more ('obese').

METHODS

The health state descriptions were modified from a published diabetes utility study. Health states included a base-case type 2 DM health state (at participants' current weight), and six health states where the weight and attendant quality of life impact varied (base case ±3%, ±5%, and ±7% weight). Utilities were elicited using the time trade-off technique. Linear regression modeling was used to estimate the utility increment or decrement associated with a one unit difference in BMI.

RESULTS

Among 96 participants, the mean age was 55 years and 51% were men. The mean BMI was 32 kg/m(2) and 84% wanted to lose weight. The mean (SD) utility for the base-case state was 0.911 (0.013). Mean utilities (utility decrements) were 0.907 (-0.004), 0.865 (-0.046) and 0.806 (-0.105) for the health states describing an increased weight of 3%, 5% and 7%, respectively; and 0.923 (+0.012), 0.940 (+0.029) and 0.949 (+0.038) for the health states describing a decreased weight of 3%, 5% and 7%, respectively. For every increase of 1 kg/m(2) BMI there was an associated decrease in utility of 0.0472 (95% CI: 0.0375, 0.0569) and for every decrease of 1 kg/m(2) BMI there was an associated increase in utility of 0.0171 (95% CI: 0.0103, 0.0238).

CONCLUSIONS

The preferences of Canadian patients with type 2 DM for diabetes-related health states varied according to the weight, and quality of life impact, associated with that health state. Increased weight had a greater effect on utilities than decreased weight.

Green synthesis of nanocomposites consisting of silver and protease alpha chymotrypsin

The synergy of ultrasonication and the exposure to light radiation was found to be necessary in the formation of nanocomposites of silver and a protease alpha chymotrypsin. The reaction was carried out in aqueous medium and the process took just less than 35 min. Ultrasonication alone formed very negligible number of nanoparticles of <100 nm size whereas light alone produced enough number but the size of the particles was >100 nm. The effects of pH (in the range of 3-5, 9-10), ultrasonication time periods (0-30 min), ultrasonication intensity (33-83 W cm(-2)), energy of light radiation (short UV, long UV and Fluorescent light) and time period of exposure (5-60 min) to different light radiations were studied. The formation of nanocomposites under these effects was followed by surface plasmon resonance (SPR) spectra, dynamic light scattering (DLS), transmission electron microscopy (TEM). Ag-chymotrypsin nanocomposites of sizes ranging from 13 to 72 nm were formed using the synergy of ultrasonication and exposure to short UV radiation. Results show that ultrasonication promoted nuclei formation, growth and reduction of polydispersity by Ostwald ripening.