Evaluation of implantable Doppler probe continuous monitoring of hepatic artery anastomosis after liver transplantation.

BACKGROUND: Thrombosis of hepatic artery anastomosis (HAT) after liver transplantation is a catastrophic and dreaded complication. Early identification of HAT can salvage the situation. To monitor the anastomosis, conventional daily transcutaneous Doppler is performed. However, it has disadvantages of being noncontinuous, operator-dependent and technically difficult. Implantable Doppler probes wrapped around the anastomosed vessel giving continuous signal may be an important tool; however, very few studies are performed to study its efficacy after intra-abdominal vascular anastomosis, and its role is not clearly established. METHODS: Patients who underwent deceased donor liver transplant surgery were part of the study. On hepatic arterial anastomosis, implantable Doppler probe was fixed for monitoring. Conventional daily transcutaneous Doppler was also performed and the results were compared. RESULTS: A total of 40 hepatic arterial anastomoses were studied. The incidence of HAT was 10.53%. For the implantable Doppler probe monitoring, sensitivity and negative predictive value was 100%, whereas specificity was 94.44% and positive predictive value was 66.66% with an overall accuracy of 95%. A mean of 10 h of lead time was gained by implantable Doppler probe monitoring. CONCLUSION: Our study showed that there was high sensitivity and negative predictive value of implantable Doppler probe monitoring system, which makes it ideal for post-operative vascular anastomoses surveillance monitoring; however, abnormal positive finding on implantable Doppler probe monitoring needs to be confirmed by conventional transcutaneous Doppler. The implantable Doppler probe monitoring, because of its round the clock and continuous nature gives us a good lead time in identifying vascular complication, which translates into graft salvage and reduction in morbidity and mortality.

Unraveling doping induced anatase-rutile phase transition in TiO2 using electron, X-ray and gamma-ray as spectroscopic probes.

The present work reports the microscopic details of anatase (A) to rutile (R) phase transformation in a Mn-doped TiO2 system. Titanium dioxide (TiO2) powder was synthesized at three different dopant percentages, namely 1, 5, and 10 atom% of Mn, by a coprecipitation technique. Time differential perturbed angular correlation (TDPAC) spectroscopy was used to identify the formation of the rutile-like phase (R*) during the phase-transition process and revealed interface nucleation to be promoted by the Mn dopant. Electron paramagnetic resonance (EPR) spectroscopy, synchrotron-based X-ray absorption near edge structure (XANES), and extended X-ray absorption fine structure (EXAFS) studies showed that Mn exhibited a mixed valence states of 2+ and 4+ at different stages of the annealing process. The rutile onset temperature gradually decreased with the increase in the Mn content. The present report proposes the mechanism for the phase transformation and details the effect of Mn on the A to R phase-transformation process. This can assist in gaining a fundamental understanding of the A to R phase-transformation process and the role of the dopant in stabilizing one phase over the other.

Novel dual incretin agonist peptide with antidiabetic and neuroprotective potential.

Glucose-dependent insulinotropic hormone (GIP) and glucagon-like peptide-1 (GLP-1) are incretin hormones that exert an array of beneficial actions on metabolism and cognitive function. GLP-1-based therapeutics have been highly successful in terms of obesity and diabetes management, however GIP therapies have found no clinical utility to date. In the present study we describe, for the first time, the therapeutic effectiveness of a novel GIP/GLP-1 hybrid peptide based on the amino acid sequences of GIP, GLP-1 and the clinically approved GLP-1 mimetic, exendin-4. The hybrid peptide, N-ac(d-Ala2)GIP/GLP-1-exe, was enzymatically stable for up to 12 h when incubated with DPP-4. N-ac(d-Ala2)GIP/GLP-1-exe significantly (P < 0.001) stimulated insulin secretion from BRIN-BD11 cells and isolated mouse islets, and evoked dose-dependent increases (P < 0.001) in cAMP production in both GIP-R and GLP-1-R transfected cells. In mice, injection of the hybrid in combination with glucose significantly (P < 0.001) reduced glucose and increased insulin concentrations, with metabolic actions evident (P < 0.05) 8 h post-injection. Twice-daily injection of N-ac(d-Ala2)GIP/GLP-1-exe to high fat fed (HFF) mice for 28 days significantly (P < 0.05-P < 0.001) reduced body weight, HbA1c, circulating glucose and insulin concentrations. Furthermore, both oral and i.p. glucose tolerance were improved (P < 0.001) and insulin sensitivity enhanced. The hybrid peptide also increased (P < 0.05-P < 0.001) beta cell number, islet area, pancreatic insulin content and islet insulin secretory responsiveness in HFF mice. Finally, N-ac(d-Ala2)GIP/GLP-1-exe treated mice exhibited improved (P < 0.01) recognition memory which was accompanied by enhanced (P < 0.05-P < 0.001) hippocampal neurogenesis, synapse formation and reduced neuronal oxidative stress. These data demonstrate for the first time the beneficial actions of the novel GIP/GLP-1 hybrid, N-ac(d-Ala2)GIP/GLP-1-exe, on glucose homeostasis and memory function in diabetes.

Hydrogen peroxide test for intraoperative bile leak detection.

BACKGROUND: Bile leakage (BL) is a common complication following liver surgery, ranging from 3 to 27% in different series. To reduce the incidence of post-operative BL various BL tests have been applied since ages, but no method is foolproof and every method has their own limitations. In this study we used a relatively simpler technique to detect the BL intra-operatively. Topical application of 1.5% diluted hydrogen peroxide (H2O2) was used to detect the BL from cut surface of liver and we compared this with conventional saline method to know the efficacy. METHODS: A total of 31 patients included all patients who underwent liver resection and donor hepatectomies as part of Living Donor Liver Transplantation. After complete liver resection, the conventional saline test followed by topical diluted 1.5% H2O2 test was performed on all. RESULTS: A BL was demonstrated in 11 patients (35.48%) by the conventional saline method and in 19 patients (61.29%) by H2O2 method. Statistically compared by Wilcoxon signed-rank test showed significant difference (P = 0.014) for minor liver resections group and (P = 0.002) for major liver resections group. CONCLUSION: The topical application of H2O2 is a simple and effective method of detection of BL from cut surface of liver. It is an easy, non-invasive, cheap, less time consuming, reproducible, and sensitive technique with no obvious disadvantages.

p19(Arf) is required for the cellular response to chronic DNA damage.

The p53 tumor suppressor is a stress sensor, driving cell cycle arrest or apoptosis in response to DNA damage or oncogenic signals. p53 activation by oncogenic signals relies on the p19(Arf) tumor suppressor, while p53 activation downstream of acute DNA damage is reported to be p19(Arf)-independent. Accordingly, p19(Arf)-deficient mouse embryo fibroblasts (MEFs) arrest in response to acute DNA damage. However, p19(Arf) is required for replicative senescence, a condition associated with an activated DNA damage response, as p19(Arf)-/- MEFs do not senesce after serial passage. A possible explanation for these seemingly disparate roles for p19(Arf) is that acute and chronic DNA damage responses are mechanistically distinct. Replicative senescence may result from chronic, low-dose DNA damage responses in which p19(Arf) has a specific role. We therefore examined the role of p19(Arf) in cellular responses to chronic, low-dose DNA-damaging agent treatment by maintaining MEFs in low oxygen and administering 0.5 G y γ-irradiation daily or 150 µM hydroxyurea, a replication stress inducer. In contrast to their response to acute DNA damage, p19(Arf)-/- MEFs exposed to chronic DNA damage do not senesce, revealing a selective role for p19(Arf) in senescence upon low-level, chronic DNA damage. We show further that p53 pathway activation in p19(Arf)-/- MEFs exposed to chronic DNA damage is attenuated relative to wild-type MEFs, suggesting a role for p19(Arf) in fine-tuning p53 activity. However, combined Nutlin3a and chronic DNA-damaging agent treatment is insufficient to promote senescence in p19(Arf)-/- MEFs, suggesting that the role of p19(Arf) in the chronic DNA damage response may be partially p53-independent. These data suggest the importance of p19(Arf) for the cellular response to the low-level DNA damage incurred in culture or upon oncogene expression, providing new insight into how p19(Arf) serves as a tumor suppressor. Moreover, our study helps reconcile reports suggesting crucial roles for both p19(Arf) and DNA damage-signaling pathways in tumor suppression.

Beneficial metabolic actions of a stable GIP agonist following pre-treatment with a SGLT2 inhibitor in high fat fed diabetic mice.

The purpose of the present study was to examine if a stable glucose-dependent insulinotropic polypeptide (GIP) agonist could exert beneficial metabolic control in diabetic mice which had been pre-treated with sodium-glucose-cotransporter-2 (SGLT2) inhibitor dapagliflozin (DAPA). High fat fed mice administered low dose streptozotocin (STZ) received vehicle, DAPA once-daily over 28 days, or DAPA once-daily for 14 days followed by (DAla(2))GIP once-daily for 14 days. Energy intake, body weight, glucose and insulin concentrations were measured at regular intervals. Glucose tolerance, insulin tolerance test, dual-energy X-ray absorptiometry (DEXA) and pancreatic histology were examined. Once-daily administration of (DAla(2))GIP for 14 days in high fat fed diabetic mice pre-treated with DAPA demonstrated significant decrease in body weight, blood glucose and increased insulin concentrations which were independent of changes in energy intake. Similarly, glucose tolerance, glucose-stimulated insulin secretion, insulin sensitivity and HOMA-ß were significantly enhanced in (DAla(2))GIP-treated mice. DEXA analysis revealed sustained percentage body fat loss with no changes in lean mass, bone mineral content and density. Pancreatic immunohistochemical analysis revealed decreased islet number and increases in islet area, beta cell area and pancreatic insulin content. The DAPA-induced increase in alpha cell area was also reversed. Additional acute in vitro and in vivo experiments confirmed that the impaired action of (DAla(2))GIP under hyperglycaemic-induced conditions was significantly reversed by DAPA treatment. These data demonstrate that (DAla(2))GIP can exert beneficial metabolic control in high fat fed diabetic mice pre-treated with DAPA. The results highlight possibility of a targeted and personalized approach using a GIP agonist and SGLT2 inhibitor for the treatment of type 2 diabetes.

Sustained treatment with a stable long-acting oxyntomodulin analogue improves metabolic control and islet morphology in an experimental model of type 1 diabetes.

AIM: To assess the therapeutic benefits of regulatory peptides other than insulin, which have to date received limited consideration in the context of type 1 diabetes. METHODS: We assessed the effects of subchronic administration of the stable, oxyntomodulin (Oxm) analogue, (d-Ser(2) )Oxm[Lys(38) -γ-glu-PAL], for 28 days in streptozotocin (STZ)-induced insulin-deficient diabetic mice. RESULTS: Twice-daily injection with (d-Ser(2) )Oxm[Lys(38) -γ-glu-PAL] significantly countered the excessive food and fluid intake in STZ-induced diabetic mice, and maintained normal body weight. Lean body mass was normalized, whilst fat mass was significantly increased compared with control STZ-induced diabetic mice. In addition, circulating glucose was significantly reduced by the Oxm analogue, whilst plasma and pancreatic insulin concentrations were increased and glucagon decreased by day 28. Plasma lipid profile was normalized by (d-Ser(2) )Oxm[Lys(38) -γ-glu-PAL] administration and circulating amylase was not significantly altered by induction of diabetes or Oxm analogue therapy. This was associated with significantly improved glucose tolerance and insulin secretion. Peripheral insulin sensitivity was also significantly improved by Oxm analogue treatment. Histological examination of pancreata showed beneficial elevations of total islet and ß-cell area, associated with an increase in the number of smaller-sized islets. Further analysis revealed enhanced islet cell proliferation relative to apoptosis in Oxm analogue-treated mice. CONCLUSION: These studies emphasize the potential of stable Oxm-based peptides, such as (d-Ser(2) )Oxm[Lys(38) -γ-glu-PAL], as therapeutic agents for insulin-deficient type 1 diabetes.

Stable oxyntomodulin analogues exert positive effects on hippocampal neurogenesis and gene expression as well as improving glucose homeostasis in high fat fed mice.

The weight-lowering and gluco-regulatory actions of oxyntomodulin (Oxm) have been well-documented however potential actions of this peptide in brain regions associated with learning and memory have not yet been evaluated. The present study examined the long-term actions of a stable acylated analogue of Oxm, (dS(2))Oxm(K-γ-glu-Pal), together with parent (dS(2))Oxm peptide, on hippocampal neurogenesis, gene expression and metabolic control in high fat (HF) mice. Groups of HF mice (n = 12) received twice-daily injections of Oxm analogues (both at 25 nmol/kg body weight) or saline vehicle (0.9% wt/vol) over 28 days. Hippocampal gene expression and histology were assessed together with evaluation of energy intake, body weight, non-fasting glucose and insulin, glucose tolerance, insulin sensitivity and lipids. Oxm analogues significantly reduced body weight, improved glucose tolerance, glucose-mediated insulin secretion, insulin sensitivity, islet architecture and lipid profile. Analysis of brain histology revealed significant reduction in hippocampal oxidative damage (8-oxoguanine), enhanced hippocampal neurogenesis (doublecortin) and improved hippocampal and cortical synaptogenesis (synaptophysin) following treatment. Furthermore, Oxm analogues up-regulated hippocampal mRNA expression of MASH1, Synaptophysin, SIRT1, GLUT4 and IRS1, and down-regulated expression of LDL-R and GSK3ß. These data demonstrate potential of stable Oxm analogues, and particularly (dS(2))Oxm(K-γ-glu-Pal) to improve metabolic function and enhance neurogenesis, synaptic plasticity, insulin signalling and exert protective effects against oxidative damage in hippocampus and cortex brain regions in HF mice.

Tracking sesamin synthase gene expression through seed maturity in wild and cultivated sesame species--a domestication footprint.

Sesamin and sesamolin are the major oil-soluble lignans present in sesame seed, having a wide range of biological functions beneficial to human health. Understanding sesame domestication history using sesamin synthase gene expression could enable delineation of the sesame putative progenitor. This report examined the functional expression of sesamin synthase (CYP81Q1) during capsule maturation (0-40 days after flowering) in three wild Sesamum species and four sesame cultivars. Among the cultivated accessions, only S. indicum (CO-1) exhibited transcript abundance of sesamin synthase along with high sesamin content similar to S. malabaricum, while the other cultivated sesame showed low expression. The sesamin synthase expression analysis, coupled with quantification of sesamin level, indicates that sesamin synthase was not positively favoured during domestication. The sesamin synthase expression pattern and lignan content, along with phylogenetic analysis suggested a close relationship of cultivated sesame and the wild species S. malabaricum. The high genetic identity between the two species S. indicum and S. malabaricum points towards the role of the putative progenitor S. malabaricum in sesame breeding programmes to broaden the genetic base of sesame cultivars. This study emphasises the need to investigate intraspecific and interspecific variation in the primary, secondary and tertiary gene pools to develop superior sesame genotypes.

Endocrine regulation of testosterone production by Leydig cells in the catfish, Clarias batrachus: probable mediators of growth hormone.

Growth hormone (GH), in the recent past, has been recognized as a potent steroid stimulating hormone independent of gonadotropin (GtH). However, the mode and mechanism of its steroidogenic action in the testis is not yet elucidated, particularly in fish. The present study was designed to understand the mode and mechanism of steroidogenic action of growth hormone in testis of the catfish, Clarias batrachus through in vivo and in vitro Leydig cell culture studies using the signaling molecule inhibitors. Exogenous administration of GtH, GH and insulin to the male catfish increased testicular and circulating testosterone level. In vitro treatment of Leydig cells with these hormones also increased testosterone production. The steroidogenic action of GH appeared to be indirect and mediated through Leydig cell produced insulin-like growth factor I (IGF-I), as the treatments with actinomycin D, cycloheximide and anti-IGF-I abolished the GH-induced testosterone production by Leydig cells. The GH-induced stimulation in IGF-I production by the isolated Leydig cells further substantiates this notion. GH appears to employ cAMP/PKA and tyrosine kinase signaling pathways to induce IGF-I production, as the adenylyl cyclase inhibitor (SQ 22,536), cAMP-dependent protein kinase (PKA) blocker (H-89) and tyrosine kinase inhibitor (lavendustin A) abolished the GH-induced IGF-I production and in turn testosterone by the Leydig cells. This study suggests that GH exerts independent androgenic effect in the catfish testis indirectly through augmenting the Leydig cell production of IGF-I.

Invading one step at a time: the role of invadopodia in tumor metastasis.

The ability to degrade extracellular matrix is critical for tumor cells to invade and metastasize. Recent studies show that tumor cells use specialized actin-based membrane protrusions termed invadopodia to perform matrix degradation. Invadopodia provide an elegant way for tumor cells to precisely couple focal matrix degradation with directional movement. Here we discuss several key components and regulators of invadopodia that have been uniquely implicated in tumor invasion and metastasis. Furthermore, we discuss existing and new therapeutic opportunities to target invadopodia for anti-metastasis treatment.

Prevalence of hepatitis C virus genotypes and impact of T helper cytokines in achieving sustained virological response during combination therapy: a study from Central India.

Characterisation of host immune response to hepatitis C virus (HCV) genotypes may have an important prognostic and therapeutic implication. Genotype-3 was more prevalent in the examined cohort and demonstrated a significantly higher response to combination therapy than genotype-1. Sustained virological response (SVR) was 94.74% in genotype-3 and 45.45% in genotype-1. The patients who achieved SVR reported higher levels of circulating T helper 1 cytokines in comparison to subjects with no SVR in both the studied groups. Besides providing local prevalence, our study might also assist in understanding the host immune mechanisms involved to achieve SVR during combination therapy in chronic HCV patients.

Intake and utilization of sorghum and maize green fodder in spotted deer under captivity.

PURPOSE: The feeding value and nutritional adequacy of two cereal fodder, viz. sorghum (Sorghum vulgare) and maize (Zea mays), were evaluated in spotted deer (Axis axis) and compared with that in sheep in two consecutive feeding trials of 35 days each. METHODS: Four spotted deer (2 years of age, 68.3 kg average body weight) and six sheep (1.5 years of age, 18.0 kg average body weight) were fed on the above two fodder types as sole feed. Nutrient digestibility and evaluations were made through two digestion studies that ended with each feeding period. RESULT: Both sorghum and maize fodder provided 11% CP and 4.4 kcal DE per gram of TDN in the two species studied. A lower intake of DM (40.6 vs 47.5 g/kg(0.75)) and other nutrients was observed in deer during maize feeding period. It was similar but lower in sheep compared to deer. The digestibility of nutrients from both fodder types was higher in deer (66-77%) than sheep (45-62%). Numerically, most of the nutrients from sorghum fodder were better digested than maize except CP and EE. Maize fodder provided a higher percentage of NDF (70.85% vs 67.90%) and ADF (37.22% vs 30.74%) with a digestibility depression of about two units in deer and three to five units in sheep. Deer and sheep lost body weight during both the sorghum (2.0 and 0.7 kg) and the maize (2.5 and 0.4 kg) feeding periods. CONCLUSION: Although the nutritive value of cereal fodder seemed optimum, a lower voluntary feed intake in both deer and sheep contributed to inadequate nutrient intake compared to standard recommendation.

Diagnosis of gastrointestinal tuberculosis: Using cytomorphological, microbiological, immunological and molecular techniques - A study from Central India.

The present study included three groups: (A) age and gender matched control (n=24) with no previous signs of M. tuberculosis complex (MTBC) infection, (B) patients (n=28) diagnosed with gastro-intestinal TB (GITB), (C) patients (n=50) with clinical and histo-pathological signs of GITB, but were culture and AFB negative. Real time assay performed using fluorescence resonance energy transfer hybridization probes showed a positivity index of 36 % in group C, i.e. 18 were found reactive from the total 50 cases studied. In addition, immune characterization of these 18 cases showed depleted CD(4) (+) count and increased levels of IFN-γ and TNF-α cytokines. No positive case was found in group A, while in group B, out of total 28 cases studied 27 were found positive. A combinatorial diagnostic approach for rapid detection and characterization of GITB might provide specific therapeutic strategies for prevention and treatment of the infection in future.