Impacts of hydrophobicity and ionicity of phendione-based cobalt(II)/(III) complexes on binding with bovine serum albumin.

For efficient designing of metallodrugs, it is imperative to analyse the binding affinity of those drugs with drug-carrying serum albumins to comprehend their structure-activity correlation for biomedical applications. Here, cobalt(II) and cobalt(III) complexes comprising three phendione ligands, [Co(phendione)3]Cl2 (1) and [Co(phendione)3]Cl3 (2), where, phendione = 1,10-phenanthroline-5,6-dione, has been chosen to contrast the impact of their hydrophobicity and ionicity on binding with bovine serum albumin (BSA) through spectrophotometric titrations. The attained hydrophobicity values using octanol/water partition coefficient method manifested that complex 1 is more hydrophobic than complex 2, which could be attributed to lesser charge on its coordination sphere. The interaction of complexes 1 and 2 with BSA using steady state fluorescence studies revealed that these complexes quench the intrinsic fluorescence of BSA through static mechanism, and the extent of quenching and binding parameters are higher for complex 2. Further thermodynamics of BSA-binding studies revealed that complexes 1 and 2 interact with BSA through hydrophobic and hydrogen bonding/van der Waals interactions, respectively. Further, UV-visible absorption, circular dichroism and synchronous fluorescence studies confirmed the occurrence of conformational and microenvironmental changes in BSA upon binding with complexes 1 and 2. Molecular docking studies have also shown that complex 2 has a higher binding affinity towards BSA as compared to complex 1. This sort of modification of ionicity and hydrophobicity of metal complexes for getting desirable binding mode/strength with drug transporting serum albumins will be a promising pathway for designing active and new kind of metallodrugs for various biomedical applications.Communicated by Ramaswamy H. Sarma.

Claudin 4 in pancreatic ß cells is involved in regulating the functional state of adult islets.

The functional state (FS) of adult pancreatic islets is regulated by a large array of regulatory molecules including numerous transcription factors. Whether any islet structural molecules play such a role has not been well understood. Here, multiple technologies including bioinformatics analyses were used to explore such molecules. The tight junction family molecule claudin 4 (Cldn4) was the highest enriched amongst over 140 structural genes analysed. Cldn4 expression was ~75-fold higher in adult islets than in exocrine tissues and was mostly up-regulated during functional maturation of developing islet cells. Cldn4 was progressively down-regulated in functionally compromised, dedifferentiating insulin-secreting ß cells and in db/db type 2 diabetic islets. Furthermore, the genetic deletion of Cldn4 impaired significantly the FS without apparently affecting pancreas morphology, islet architectural structure and cellular distribution, and secretion of enteroendocrine hormones. Thus, we suggest a previously unidentified role for Cldn4 in regulating the FS of islets, with implications in translational research for better diabetes therapies.

Why do patients not kneel after total knee replacement? Is neuropathic pain a contributing factor?

AIMS: Despite kneeling being an important and valued function of the knee, a proportion of patients are unable to kneel following arthroplasty. We explore the reasons for this, and assess whether neuropathic pain is a contributing factor. METHODS: In this observational study, data was collected prospectively for 134 knees. At one year follow-up, patients completed a semi-structured questionnaire, the Oxford Knee Score (OKS), and the painDETECT score. Ability to kneel was assessed by question 7 of the OKS. Change in kneeling ability was assessed using Wilcoxon signed-rank test, normal data with independent t-test, and a regression and ANOVA analysis performed to assess predictors of kneeling ability. RESULTS: 88% of patients had tried kneeling post-operatively. There was no change in kneeling ability for the whole cohort from pre- to post-operatively (p = 0.313). Patient reasons for not kneeling varied. Male gender, younger age and a reduced pain score were all significantly associated with a greater ability to kneel postoperatively. There was a trend towards an improved ability with increased flexion. Mean pain scores for all kneeling abilities lay within the nociceptive rather than neuropathic range. CONCLUSION: Kneeling ability varies greatly post-knee replacement, and is multifactorial. Greater pain is a contributing factor to the inability to kneel postoperatively, but this appears to be nociceptive rather than neuropathic in nature.

RNA-Seq Analysis of Islets to Characterise the Dedifferentiation in Type 2 Diabetes Model Mice db/db.

Type 2 diabetes (T2D) is a global health issue and dedifferentiation plays underlying causes in the pathophysiology of T2D; however, there is a lack of understanding in the mechanism. Dedifferentiation results from the loss of function of pancreatic ß-cells alongside a reduction in essential transcription factors under various physiological stressors. Our study aimed to establish db/db as an animal model for dedifferentiation by using RNA sequencing to compare the gene expression profile in islets isolated from wild-type, db/+ and db/db mice, and qPCR was performed to validate those significant genes. A reduction in both insulin secretion and the expression of Ins1, Ins2, Glut2, Pdx1 and MafA was indicative of dedifferentiation in db/db islets. A comparison of the db/+ and the wild-type islets indicated a reduction in insulin secretion perhaps related to the decreased Mt1. A significant reduction in both Rn45s and Mir6236 was identified in db/+ compared to wild-type islets, which may be indicative of pre-diabetic state. A further significant reduction in RasGRF1, Igf1R and Htt was also identified in dedifferentiated db/db islets. Molecular characterisation of the db/db islets was performed via Ingenuity analysis which identified highly significant genes that may represent new molecular markers of dedifferentiation.

An overview of type 2 diabetes and importance of vitamin D3-vitamin D receptor interaction in pancreatic ß-cells.

One significant health issue that plagues contemporary society is that of Type 2 diabetes (T2D). This disease is characterised by higher-than-average blood glucose levels as a result of a combination of insulin resistance and insufficient insulin secretions from the ß-cells of pancreatic islets of Langerhans. Previous developmental research into the pancreas has identified how early precursor genes of pancreatic ß-cells, such as Cpal, Ngn3, NeuroD, Ptf1a, and cMyc, play an essential role in the differentiation of these cells. Furthermore, ß-cell molecular characterization has also revealed the specific role of ß-cell-markers, such as Glut2, MafA, Ins1, Ins2, and Pdx1 in insulin expression. The expression of these genes appears to be suppressed in the T2D ß-cells, along with the reappearance of the early endocrine marker genes. Glucose transporters transport glucose into ß-cells, thereby controlling insulin release during hyperglycaemia. This stimulates glycolysis through rises in intracellular calcium (a process enhanced by vitamin D) (Norman et al., 1980), activating 2 of 4 proteinases. The rise in calcium activates half of pancreatic ß-cell proinsulinases, thus releasing free insulin from granules. The synthesis of ATP from glucose by glycolysis, Krebs cycle and oxidative phosphorylation plays a role in insulin release. Some studies have found that the ß-cells contain high levels of the vitamin D receptor; however, the role that this plays in maintaining the maturity of the ß-cells remains unknown. Further research is required to develop a more in-depth understanding of the role VDR plays in ß-cell function and the processes by which the beta cell function is preserved.

Is there a weekend effect in hip fracture patients presenting to a United Kingdom teaching hospital?

AIM: To compare mortality and time-to-surgery of patients admitted with hip fracture to our teaching hospital on weekdays vs weekends. METHODS: Data was prospectively collected and retrospectively analysed for 816 hip fracture patients. Multivariate logistic regression was carried out on 3 binary outcomes (time-to-surgery < 36 h; 30-d mortality; 120-d mortality), using the explanatory variables time-of-admission; age; gender; American Society of Anesthesiologist (ASA) grade; abbreviated mental test score (AMTS); fracture type; accommodation admitted from; walking ability outdoors; accompaniment outdoors and season. RESULTS: Baseline characteristics were not statistically different between those admitted on weekdays vs weekends. Weekend admission was not associated with an increased time-to-surgery (P = 0.975), 30-d mortality (P = 0.842) or 120-d mortality (P = 0.425). Gender (P = 0.028), ASA grade (P < 0.001), AMTS (P = 0.041) and accompaniment outdoors (P = 0.033) were significant co-variates for 30-d mortality. Furthermore, age (P < 0.001), gender (P = 0.011), ASA grade (P < 0.001), AMTS (P < 0.001) and accompaniment outdoors (P = 0.033) all significantly influenced mortality at 120 d. ASA (P < 0.001) and season (P = 0.014) had significant effect on the odds of undergoing surgery in under 36 h. CONCLUSION: Weekend admission was not associated with increased time-to-surgery or mortality in hip fracture patients. Demographic factors affect mortality in accordance with previous published reports.

Pigment epithelium-derived factor (PEDF) regulates metabolism and insulin secretion from a clonal rat pancreatic beta cell line BRIN-BD11 and mouse islets.

Pigment epithelium-derived factor (PEDF) is a multifunctional glycoprotein, associated with lipid catabolism and insulin resistance. In the present study, PEDF increased chronic and acute insulin secretion in a clonal rat ß-cell line BRIN-BD11, without alteration of glucose consumption. PEDF also stimulated insulin secretion from primary mouse islets. Seahorse flux analysis demonstrated that PEDF did not change mitochondrial respiration and glycolytic function. The cytosolic presence of the putative PEDF receptor - adipose triglyceride lipase (ATGL) - was identified, and ATGL associated stimulation of glycerol release was robustly enhanced by PEDF, while intracellular ATP levels increased. Addition of palmitate or ex vivo stimulation with inflammatory mediators induced ß-cell dysfunction, effects not altered by the addition of PEDF. In conclusion, PEDF increased insulin secretion in BRIN-BD11 and islet cells, but had no impact on glucose metabolism. Thus elevated lipolysis and enhanced fatty acid availability may impact insulin secretion following PEDF receptor (ATGL) stimulation.

Unilateral malignant struma ovarii in a case of bilateral ovarian teratoma with raised CA-125 level: a rare case with treatment dilemmas.

Struma ovarii are specialized form of mature ovarian teratoma comprised predominantly of thyroid tissue (>50%). Most of the struma ovarii are benign; rarely can they undergo malignant transformation. Elevated CA-125 levels with benign struma ovarii have been seen in only 5 cases in literature. The association of malignant struma ovarii and high CA-125 levels with pseudo-Meig syndrome has been reported in only 2 cases in English literature. We describe a case of a 46-year-old multigravida who presented with an abdominal mass and raised CA-125 levels. Radiological investigations revealed bilateral cystic adnexal masses with ossified elements on left side suggesting a teratoma. Intraoperative frozen section and final pathology revealed bilateral teratoma with follicular variant of papillary thyroid carcinoma arising in the left ovary. To the best of our knowledge, this is the first case of malignant struma ovarii in combination with bilateral teratoma. The dilemmas related to preoperative diagnoses with elevated CA-125 levels, mimicking an epithelial ovarian neoplasm; intraoperative frozen section consultation; management and follow-up issues in this rare malignancy are discussed.

Iron loading and oxidative stress in the Atm-/- mouse liver.

Ataxia-Telangiectasia (A-T) is an autosomal recessive disorder resulting in a myriad of abnormalities, including progressive neurodegeneration and cancer predisposition. At the cellular level, A-T is a disease of chronic oxidative stress (OS) causing damage to proteins, lipids, and DNA. OS is contributed to by pro-oxidative transition metals such as iron that catalyze the conversion of weakly reactive oxygen species to highly reactive hydroxyl radicals. Iron-associated OS has been linked to neurodegeneration in Alzheimer's and Parkinson's diseases and development of lymphoid tumors (which afflict ∼30% of A-T patients). To investigate iron regulation in A-T, iron indexes, regulatory genes, and OS markers were studied in livers of wild-type and Ataxia telangiectasia mutated (Atm) null mice on control or high-iron diets. Atm(-/-) mice had increased serum iron, hepatic iron, and ferritin and significantly higher Hepcidin compared with wild-type mice. When challenged with the high-iron diet, Bmp6 and Hfe expression was significantly increased. Atm(-/-) mice had increased protein tyrosine nitration and significantly higher Heme Oxygenase (decycling) 1 levels that were substantially increased by a high-iron diet. Ferroportin gene expression was significantly increased; however, protein levels were unchanged. We demonstrate that Atm(-/-) mice have a propensity to accumulate iron that is associated with a significant increase in hepatic OS. The iron-induced increase in hepcidin peptide in turn suppresses ferroportin protein levels, thus nullifying the upregulation of mRNA expression in response to increased OS. Our results suggest that increased iron status may contribute to the chronic OS seen in A-T patients and development of disease pathology.

Is a raised CA 19-9 level diagnostic for a cholangiocarcinoma in patients with no history of sclerosing cholangitis ?

BACKGROUND/AIM: A cholangiocarcinoma, the second most common primary hepatic malignancy, can present with diagnostic dilemmas. The aim of this study is to assess the role of CA 19-9 in patients with a cholangiocarcinoma without primary sclerosing cholangitis. METHODS: The prospectively collected information on patients with biopsy-proven cholangiocarcinomas who had the CA 19-9 level measured was obtained (n = 68) from our computer database and medical records. These patients were compared with patients who had benign liver tumours (n = 25) and benign bile duct strictures (n = 13) who also had their CA 19-9 concentration measured. RESULTS: Sensitivity and specificity of CA 19-9 in the diagnosis of a cholangiocarcinoma were 77.9 and 76.3%, respectively, when using a cut-off value of 35 kU/l, while sensitivity and specificity were 67.5 and 86.8%, respectively, when the cut-off value was raised to 100 kU/l. The specificity was found to be higher in patients with peripheral cholangiocarcinomas (96%) using a CA 19-9 cut-off value >100 kU/l. A CA 19-9 value >600 kU/l was associated with non-resectable tumours (p = 0.05). CONCLUSIONS: This study demonstrates that CA 19-9 is a useful adjunct in the diagnosis of cholangiocarcinomas without primary sclerosing cholangitis, especially in the diagnosis of peripheral cholangiocarcinomas. However, it does not provide a reliable guide for the pathological staging of these tumours.

A study on the effects of some reinforcers to improve performance of employees in a retail industry.

Two field experiments were conducted in the Business Information Technology Department of a major retail industry to analyze the impact of positive task performance reinforcers. The employees were divided into two broad groups - those performing complex tasks and those performing relatively simpler tasks. The first group was further divided into two subgroups, one being reinforced with money and paid leave and the other with feedback. Both the subgroups showed a significant improvement in performance behavior. However, feedback had a stronger effect on task performance even after the reinforcement was withdrawn. The second group of employees was allowed to choose reinforcers of their liking. Two simple techniques, a casual dress code and flexible working hours chosen by them, had a positive effect on their performance, which continued even after 6 months into the intervention. Besides, the procedure for the second group required no monetary or work-time loss to the employer.

Conventional versus piggyback technique of caval implantation; without extra-corporeal veno-venous bypass. A comparative study.

Conventional orthotopic liver transplantation (CON-LT) involves resection of recipient cava, usually with extra-corporeal circulation (veno-venous bypass, VVB), while in the piggyback technique (PC-LT) the cava is preserved. Along with a temporary portacaval shunt (TPCS), better haemodynamic maintenance is purported with PC-LT. A prospective, consecutive series of 384 primary transplants (2000-2003) were analysed, 138 CON-LT (with VVB) and 246 PC-LT (54 without TPCS). Patient/donor characteristics were similar in the two groups. PC-LT required less usage of fresh-frozen plasma and platelets, intensive care stay, number of patients requiring ventilation after day 1 and total days spent on ventilator. The results were not different when comparing, total operating and warm ischaemia time (WIT), red cell usage, requirement for renal support, day 3 serum creatinine and total hospital stay. TPCS had no impact on outcome other than WIT (P = 0.02). Three patients in PC-LT group (three of 246;1.2%) developed caval outflow obstruction (P = 0.02). There was no difference in short- or long-term graft or patient survival. PC-LT has an advantage over CON-LT unsing VVB with respect to intraoperative blood product usage, postoperative ventilation requirement and ITU stay. VVB is no longer required and TPCS may be used selectively in adult transplantation.

Multivariate and univariate analysis of prognostic factors following resection in HCC: the Birmingham experience.

BACKGROUND: The aim of this study was to look into our experience of resection for hepatocellular carcinomas (HCCs) in a tertiary Hepatobiliary and Liver Transplant Unit in the UK. METHODS: A retrospective analysis of our prospective database was carried out. RESULTS: 715 cases of HCC were seen. 100 (13.9%) underwent hepatic resection and 159 (22.2%) orthotopic liver transplant. The 1-, 3- and 5-year overall survival following resection was 75.3, 37.0 and 21.5% respectively. Factors affecting long-term survival included resection margin (p < 0.001), recurrence (p < 0.007), alpha-fetoprotein >50 (p < 0.001) and serum albumin (p < 0.03). On multivariate analysis, recurrence (p < 0.001) and histological grade (p < 0.044) were significant. The 1- and 3-year recurrence rates were 27.3 and 72.5% respectively. Histological grade (p < 0.007), alpha-fetoprotein >50 (p < 0.033), female gender (p < 0.016) and portal vein involvement (p < 0.016) were significant in recurrence. CONCLUSIONS: Resection data from the East may not be comparable to the West owing to the higher transplant activity in the latter. Liver function tests and imaging would be sufficient to assess liver function prior to hepatic resection. HCC with cirrhosis should be assessed by a transplant unit prior to any treatment. The MELD (Model for End-Stage Liver Disease) score would be a valuable preoperative tool in the assessment of cirrhotics.

Transesophageal Echocardiographic Examination of Left Subclavian Artery Branches.

This preliminary study demonstrates the feasibility of examining the proximal segments of the branches of the left subclavian artery during probe withdrawal toward the end of a routine transesophageal echocardiographic study. The branches identified most commonly were the vertebral and the internal mammary arteries.

Traumatic Rupture of Atherosclerotic Plaque Producing Aortic Isthmus Dissection.

Traumatic rupture of aortic isthmus atherosclerotic plaque resulting in dissection has not been documented through the use of either invasive or noninvasive diagnostic modalities. We describe an elderly patient in whom transesophageal echocardiography and three-dimensional reconstruction of multiplane transesophageal two-dimensional images clearly demonstrated the traumatic dissection to be due to rupture of a large atherosclerotic plaque located in the aortic isthmus. The patient had experienced blunt trauma to the chest from the impact of the steering wheel during an automobile accident.

Three-Dimensional Echocardiographic Assessment of Aortic Dissection.

In the present study, we report our experience of using three-dimensional reconstruction of transesophageal two-dimensional echocardiographic images in the assessment of aortic dissection (22 patients), aortic rupture (1 patient), aortic aneurysm without dissection (2 patients), and aortic tumor (1 patient).

Examination of Left External and Internal Carotid Arteries During Transesophageal Echocardiography.

The present study demonstrates the feasibility of delineating the carotid bulb and the proximal portions of the left external and left internal carotid arteries during transesophageal examination. This was accomplished by slowly and carefully withdrawing the probe from the esophagus into the pharynx.