Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

A novel synthetic small molecule DMFO targets Nrf2 in modulating proinflammatory/antioxidant mediators to ameliorate inflammation

Inflammation is a protective immune response against invading pathogens, however, dysregulated inflammation is detrimental. As the complex inflammatory response involves multiple mediators, including the involvement of reactive oxygen species, concomitantly targeting proinflammatory and antioxidant check-points may be a more rational strategy. We report the synthesis and anti-inflammatory/antioxidant activity of a novel indanedione derivative DMFO. DMFO scavenged reactive oxygen species (ROS) in in-vitro radical scavenging assays and in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. In acute models of inflammation (carrageenan-induced inflammation in rat paw and air pouch), DMFO effectively reduced paw oedema and leucocyte infiltration with an activity comparable to diclofenac. DMFO stabilised mast cells (MCs) in in-vitro A23187 and compound 48/80-induced assays. Additionally, DMFO stabilised MCs in an antigen (ovalbumin)-induced MC degranulation model in-vivo, without affecting serum IgE levels. In a model of chronic immune-mediated inflammation, Freund's adjuvant-induced arthritis, DMFO reduced arthritic score and contralateral paw oedema, and increased the pain threshold with an efficacy comparable to diclofenac but without being ulcerogenic. Additionally, DMFO significantly reduced serum TNFα levels. Mechanistic studies revealed that DMFO reduced proinflammatory genes (IL1β, TNFα, IL6) and protein levels (COX2, MCP1), with a concurrent increase in antioxidant genes (NQO1, haem oxygenase 1 (HO-1), Glo1, Nrf2) and protein (HO-1) in LPS-stimulated macrophages. Importantly, the anti-inflammatory/antioxidant effect on gene expression was absent in primary macrophages isolated from Nrf2 KO mice suggesting an Nrf2-targeted activity, which was subsequently confirmed using siRNA transfection studies in RAW macrophages. Therefore, DMFO is a novel, orally-active, safe (even at 2 g/kg p.o.), a small molecule which targets Nrf2 in ameliorating inflammation.

Oxidative Stress and NLRP3-Inflammasome Activity as Significant Drivers of Diabetic Cardiovascular Complications: Therapeutic Implications

It is now increasingly appreciated that inflammation is not limited to the control of pathogens by the host, but rather that sterile inflammation which occurs in the absence of viral or bacterial pathogens, accompanies numerous disease states, none more so than the complications that arise as a result of hyperglycaemia. Individuals with type 1 or type 2 diabetes mellitus (T1D, T2D) are at increased risk of developing cardiac and vascular complications. Glucose and blood pressure lowering therapies have not stopped the advance of these morbidities that often lead to fatal heart attacks and/or stroke. A unifying mechanism of hyperglycemia-induced cellular damage was initially proposed to link elevated blood glucose levels with oxidative stress and the dysregulation of metabolic pathways. Pre-clinical evidence has, in most cases, supported this notion. However, therapeutic strategies to lessen oxidative stress in clinical trials has not proved efficacious, most likely due to indiscriminate targeting by antioxidants such as vitamins. Recent evidence now suggests that oxidative stress is a major driver of inflammation and vice versa, with the latest findings suggesting not only a key role for inflammatory pathways underpinning metabolic and haemodynamic dysfunction in diabetes, but furthermore that these perturbations are driven by activation of the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome. This review will address these latest findings with an aim of highlighting the interconnectivity between oxidative stress, NLRP3 activation and inflammation as it pertains to cardiac and vascular injury sustained by diabetes. Current therapeutic strategies to lessen both oxidative stress and inflammation will be emphasized. This will be placed in the context of improving the burden of these diabetic complications.

Survey of psychotropic medication: usage in a large mental handicap hospital

The populations in the large mental handicap hospitals are known to be diverse, ranging from elderly non-psychiatric residential groups to acutely psychotic and behaviourally disturbed patients. At present demographic variables, medical and psychiatric characteristics of populations in these hospitals are changing in parallel with implementation of community care and resettlement programmes. In resettlement programmes, discharge priorities have been given to the easy to manage and less dependent residents while new challenging behavioural units and admission assessment wards are being opened to care for the multi-handicapped population.

Heterocyclic homoprostanoid derivative attenuates monoarthritis in rats: An in vitro and in vivo preclinical paradigm

From our lab, among the nineteen heterocyclic homoprostanoids (HHPs), three derivatives (compounds 3, 3b and 3c) exerted antioxidant and anti-inflammatory activity. Present study is an extension of the earlier work, and, is designed to establish their therapeutic potential in monoarthritis in rats. In addition, their possible mechanism of action would be investigated. A battery of in vitro tests such as lipopolysaccharide (LPS)-induced nitrite (NO)/reactive oxygen species (ROS) and NO/interleukin (IL)-6 generation in murine macrophages and whole blood (WhB), respectively were conducted. Later, in vitro cyclooxygenase (COX) enzyme inhibitory activity was also evaluated. All the tested compounds showed comparable efficacy against ROS and NO in LPS-stimulated murine macrophages. However, compound 3 did not exert inhibitory effect on LPS-induced NO/IL-6 generation in WhB assay. Compounds (3b and 3c) inhibited the NO generation in LPS-stimulated WhB. However, only compound 3b reversed the raised IL-6 levels in this assay. None of the test compounds inhibited COX iso-enzymes in the in vitro assay. All three HHPs showed comparable efficacy against carrageenan-induced paw inflammation. However, none of them exhibited any dose-dependent effect in this model. Based upon previous reports, compound 3c was explored against adjuvant-induced monoarthritis (AIA) in male Sprague-Dawley rats, where it exerted promising therapeutic effect. In addition to radiological and histological examinations of tibio-tarsal joint, various parameters such as chronic inflammation/pain, clinical score, interleukin (IL)-6 levels and complete blood cell profile were evaluated in AIA rats. Chronic treatment with 3c halted the disease progression in rats, improved the overall health of animals, as demonstrated by haematological, clinical scoring and joint examinations (radiological and histopathological). Inhibitory effect on elevated IL-6 in AIA rats suggested the possible mechanism of 3c on cytokine signalling. Overall, the study supports the anti-arthritic potential of compound 3c.

In vivo Evaluation of Two Thiazolidin-4-one Derivatives in High Sucrose Diet Fed Pre-diabetic Mice and Their Modulatory Effect on AMPK, Akt and p38 MAP Kinase in L6 Cells

We had previously demonstrated the anti-diabetic potential and pancreatic protection of two thiazolidin-4-one derivatives containing nicotinamide moiety (NAT-1 and NAT-2) in STZ-induced diabetic mice. However, due to the limitations of the STZ model, we decided to undertake a detailed evaluation of anti-diabetic potential of the molecules on a high sucrose diet (HSD) fed diabetic mouse model. Further, in vitro mechanistic studies on the phosphorylation of AMPK, Akt and p38 MAP kinase in L6 myotubes and anti-inflammatory studies in RAW264.7 mouse monocyte macrophage cells were performed. 15 months of HSD induced fasting hyperglycaemia and impaired glucose tolerance in mice. Treatment with NAT-1 and NAT-2 (100 mg/kg) for 45 days significantly improved the glucose tolerance and lowered fasting blood glucose levels compared to untreated control. An improvement in the elevated triglycerides and total cholesterol levels, and favorable rise in HDL cholesterol were also observed with test drug treatment. Also, no major changes were observed in the liver (albumin, AST and ALT) and kidney (creatinine and urea) parameters. This was further confirmed in their respective histology profiles which revealed no gross morphological changes. In L6 cells, significant phosphorylation of Akt and p38 MAP kinase proteins were observed with 100 μM of NAT-1 and NAT-2 with no significant changes in phosphorylation of AMPK. The molecules failed to exhibit anti-inflammatory activity as observed by their effect on the generation of ROS and nitrite, and nuclear levels of NF-κB in LPS-stimulated RAW264.7 cells. In summary, the molecules activated Akt and p38 MAP kinase which could have partly contributed to their anti-hyperglycaemic and hypolipidemic activities in vivo.

Dose-related antihyperglycemic and hypolipidemic effects of two novel thiazolidin-4-ones in a rodent model of metabolic syndrome

BACKGROUND

The replacement of the thiazolidinedione moiety with a thiazolidinone may yield antidiabetic compounds with similar pleiotropic effects. Hence, the aim of the present study was to explore the dose-related antihyperglycemic and hypolipidemic effects of two synthesized novel thiazolidin-4-one derivatives, one with a nicotinamide and the other with a p-chlorophenoxyacetamide substitution at the N3 position of the thiazolidinone ring (NAT1 and PAT1, respectively), in a rodent model of metabolic syndrome (MetS).

METHODS

Metabolic syndrome was induced in Wistar rats by neonatal administration of monosodium glutamate (i.p.) on 4 consecutive days followed by high-sucrose diet feeding for 6 months. The effects of NAT1 (33 and 66 mg/kg) and molar equivalent doses of PAT1 (40 and 80 mg/kg) on relevant biochemical parameters were evaluated. Because MetS is a state of chronic low-grade inflammation, we also evaluated the effects of these compounds on proinflammatory markers, namely interleukin (IL)-6, tumor necrosis factor (TNF)-α, reactive oxygen species (ROS), and nitric oxide (NO).

RESULTS

Both NAT1 and PAT1 attenuated hyperglycemia, hypertriglyceridemia, hypoalphalipoproteinemia, and glucose intolerance. PAT1 exhibited superior antihyperglycemic and antihypoalphalipoproteinemic effects than NAT1. However, NAT1 had a better triglyceride-lowering effect. At the lower dose tested, both compounds significantly reduced elevated malondialdehyde levels. In addition, PAT1 (80 mg/kg) restored hepatic superoxide dismutase enzyme levels. There was a tendency for NAT1 and PAT1 to inhibit elevated hepatic IL-6 and TNF-α levels, but the differences did not reach statistical significance. In addition, PAT1 exhibited in vitro anti-inflammatory activity by reducing proinflammatory ROS and NO levels in RAW264.7 macrophages.

CONCLUSIONS

The novel thiazolidin-4-ones NAT1 and PAT1 could be potential pleiotropic drug candidates targeting MetS.

Frequency of Epstein--Barr virus infection as detected by messenger RNA for EBNA 1 in histologically proven gastric adenocarcinoma in patients presenting to a tertiary care center in South India

BACKGROUND

Epstein-Barr virus (EBV)-associated gastric carcinoma is a relatively uncommon entity detected in approximately 10% of gastric adenocarcinoma.

OBJECTIVE

The purpose of this study is to estimate the frequency of EBV-associated gastric carcinoma and also to assess the nature of presentation, any significant difference between this subgroup and EBV-negative gastric adenocarcinomas with respect to age and sex predilection, lymph nodal status, site of presentation.

MATERIALS AND METHODS

We prospectively analyzed 100 cases of gastric adenocarcinoma who underwent either a partial or total gastrectomy during the period from March 2010 to August 2011. The tumour and the corresponding normal gastric tissue from the same patient were analyzed for the presence of Epstein-Barr nuclear antigen 1 (EBNA1) messenger ribonucleic acid (mRNA) by real-time polymerase chain reaction (PCR).

RESULT

EBV was detected in 6% cases of gastric adenocarcinoma. All the positive patients were males. The majority of cases involved the proximal stomach and there was variable lymph nodal involvement.

CONCLUSION

Our study endorses that there is an association between EBV infection and gastric adenocarcinoma in the Indian population. There was no significant difference between this subgroup and EBV-negative gastric adenocarcinomas with respect to age and sex predilection, lymph nodal status and site of presentation. Short-term follow-up of this subgroup of patients seems to indicate a good overall prognosis after appropriate treatment. However, a larger study with long-term follow-up is needed to further establish the role of EBV in gastric adenocarcinoma in this study population.

Multi-target drugs to address multiple checkpoints in complex inflammatory pathologies: evolutionary cues for novel "first-in-class" anti-inflammatory drug candidates: a reviewer's perspective

Inflammation is a complex, metabolically expensive process involving multiple signaling pathways and regulatory mechanisms which have evolved over evolutionary timescale. Addressing multiple targets of inflammation holistically, in moderation, is probably a more evolutionarily viable strategy, as compared to current therapy which addresses drug targets in isolation. Polypharmacology, addressing multiple targets, is commonly used in complex ailments, suggesting the superior safety and efficacy profile of multi-target (MT) drugs. Phenotypic drug discovery, which generated successful MT and first-in-class drugs in the past, is now re-emerging. A multi-pronged approach, which modulates the evolutionarily conserved, robust and pervasive cellular mechanisms of tissue repair, with AMPK at the helm, regulating the complex metabolic/immune/redox pathways underlying inflammation, is perhaps a more viable strategy than addressing single targets in isolation. Molecules that modulate multiple molecular mechanisms of inflammation in moderation (modulating TH cells toward the anti-inflammatory phenotype, activating AMPK, stimulating Nrf2 and inhibiting NFκB) might serve as a model for a novel Darwinian "first-in-class" therapeutic category that holistically addresses immune, redox and metabolic processes associated with inflammatory repair. Such a multimodal biological activity is supported by the fact that several non-calorific pleiotropic natural products with anti-inflammatory action have been incorporated into diet (chiefly guided by the adaptive development of olfacto-gustatory preferences over evolutionary timescales) rendering such molecules, endowed with evolutionarily privileged molecular scaffolds, naturally oriented toward multiple targets.

Prevention of Parastomal Hernia Using Pre-peritoneal Mesh - Long Term Outcome of a Prospective Study

BACKGROUND

Parastomal hernia is a frequent complication after stoma formation. The objective of this prospective study was to find long-term outcome of prophylactic mesh placement in the pre-peritoneal space in order to prevent parastomal hernia.

METHODS

Patients undergoing elective formation of permanent stoma were included in the study. A polypropylene mesh was placed in the pre-peritoneal space without any anchoring stitches and bowel was taken out through a central circular hole made in the mesh. These patients were followed up for 5 years-by clinical examination and CT scan when needed.

RESULTS

A total of 42 patients were included in the study. These patients were followed up for a median period of 60 months (range 32-100 months). Twelve patients died before the 5-year follow up due to causes unrelated to stoma. As two patients were unable to be contacted, 28 patients remained in the long-term follow up. Three cases of parastomal hernia were detected after 5 years. None of these patients required repairing of the parastomal hernia. However, a previous study conducted 3 years ago found 4 cases of parastomal hernia that was treated by resiting the stomas. Therefore the total number of parastomal hernia detected in our series is 7 (incidence 25%).

CONCLUSION

Putting a pre-peritoneal polypropylene mesh is an easy, quick and inexpensive method, and easy to learn. The outcome is better than creating stomas without mesh, but further studies are needed to explore potential benefits of different types of mesh and their methods of positioning and anchoring.

Prevention of Parastomal Hernia Using Pre-peritoneal Mesh - Long Term Outcome of a Prospective Study

BACKGROUND

Parastomal hernia is a frequent complication after stoma formation. The objective of this prospective study was to find long-term outcome of prophylactic mesh placement in the pre-peritoneal space in order to prevent parastomal hernia.

METHODS

Patients undergoing elective formation of permanent stoma were included in the study. A polypropylene mesh was placed in the pre-peritoneal space without any anchoring stitches and bowel was taken out through a central circular hole made in the mesh. These patients were followed up for 5 years-by clinical examination and CT scan when needed.

RESULTS

A total of 42 patients were included in the study. These patients were followed up for a median period of 60 months (range 32-100 months). Twelve patients died before the 5-year follow up due to causes unrelated to stoma. As two patients were unable to be contacted, 28 patients remained in the long-term follow up. Three cases of parastomal hernia were detected after 5 years. None of these patients required repairing of the parastomal hernia. However, a previous study conducted 3 years ago found 4 cases of parastomal hernia that was treated by resiting the stomas. Therefore the total number of parastomal hernia detected in our series is 7 (incidence 25%).

CONCLUSIONS

Putting a pre-peritoneal polypropylene mesh is an easy, quick and inexpensive method, and easy to learn. The outcome is better than creating stomas without mesh, but further studies are needed to explore potential benefits of different types of mesh and their methods of positioning and anchoring.

Novel 2,5-disubstituted-1,3,4-oxadiazoles as anti-inflammatory drugs

OBJECTIVE

1,3,4-oxadiazole ring is a versatile moiety with a wide range of pharmacological properties. The present work deals with the synthesis and evaluation of the anti-inflammatory activity of two novel 2,5-disubstituted-1,3,4-oxadiazoles (OSD and OPD).

MATERIALS AND METHODS

Carrageenan-induced rat hind paw edema was employed as an acute model of inflammation. For evaluating sub-acute anti-inflammatory activity, carrageenan-induced inflammation in rat air pouch was employed. Complete Freund's adjuvant-induced arthritis in rats was used as a model of chronic inflammation. To evaluate in vitro anti-inflammatory activity, lipopolysaccharide (LPS)-stimulated RAW264.7 cells were used.

RESULTS

OSD (100 mg/kg) reduced carrageen-induced paw edema by 60%, and OPD (100 mg/kg) produced a modest 32.5% reduction. OSD also reduced leukocyte influx and myeloperoxidase in carrageenan-induced rat air pouch model. In complete Freund's adjuvant-induced arthritis model, both OSD and OPD (200 mg/kg for 14 days) reduced paw edema and NO levels. In LPS-stimulated RAW264.7 cells, OSD and OPD inhibited formation of nitric oxide and reactive oxygen species, with OPD showing a better activity in comparison to OSD.

CONCLUSIONS

OSD was the better of the two compounds in in vivo models of inflammation. The o-phenol substitution at position 2 of oxadiazole ring in OSD may be responsible for its better in vivo anti-inflammatory activity. The ability of the compounds to inhibit LPS-induced pro-inflammatory mediator release suggests an anti-inflammatory mechanism targeting LPS-TLR4-NF-κB signalling pathway, which needs to be explored in detail. The disparate efficacy in vitro and in vivo also requires in-depth evaluation of the pharmacokinetics of these novel oxadiazoles.

Goblet cells carcinoid with mucinous adenocarcinoma of the vermiform appendix: a step towards the unitary intestinal stem cell theory?

Associations of various histotypes in appendiceal neoplasms may help elucidate the histogenesis of such uncommon tumors. We present the fourth published case of Goblet Cell Carcinoid (GCC) associated with mucinous adenocarcinoma of the appendix. This association has been described only for GCC and not for classic appendix carcinoids which are thought to originate from neuroendocrine-committed cells. The GCC-mucinous association adds more towards the theory of a pluripotent intestinal stem cell with amphicrine possibilities of differentiation.

Modulatory effects of sesamol in dinitrochlorobenzene-induced inflammatory bowel disorder in albino rats

BACKGROUND

Inflammatory bowel disease (IBD) is a chronic inflammatory condition of gastrointestinal tract of immune, genetic and environmental origin. In the present study, we examined the effect of sesamol (SES), the main anti-oxidative constituent of Sesamum indicum (sesame seed) Linn. in the dinitrochlorobenzene (DNCB)-induced model for IBD in rats.

METHODS

The groups were divided into normal control, DNCB control, SES and sulfasalazine (SS). On day 24, the rats were killed, colon removed and the macroscopic, biochemical and histopathological evaluations were performed.

RESULTS

The levels of MPO, TBARS and nitrite increased significantly (p < 0.05) in the DNCB group, whereas reduced significantly in the SES, SS treated groups. Serum nitrite levels were found to be insignificant between the different groups. IL-6 and TNF-α levels were significantly high in the DNCB group.

CONCLUSIONS

We conclude the mucosal protective effect of SES on colon due to its potent antioxidant actions. Further investigation is required in a chronic model of different rodent strain for its role involved in the cytokine pathway.

"Left-sided" Chilaiditi sign? A large gastric perforation with secondary pancreatitis

BACKGROUND

Although the Chilaiditi sign correctly underestimates the radiological presence of air-under-the-diaphragm, in few cases it has lead to delays in the diagnosis of underlying pneumoperitoneum. In this article we report the case of a young lady presenting with acute pancreatitis and radiographic findings of "left-sided" Chilaiditi sign with underlying a large gastric perforation.

CASE REPORT

A 35 year old Caucasian female presented to the Emergency Department with a twenty-four hour history of severe epigastric pain radiating into her back. Stable observations, mildly raised white cell count, increased amylase and subdiaphragmatic radiolucency were interpreted as acute pancreatitis with Chilaiditi sign and treated accordingly. Twenty-four hours later the deterioration of the clinical conditions required a CT scan and an emergency laparotomy that lead to the diagnosis of a large gastric perforation. However, after several days she died of a disseminated intravascular coagulation in the Intensive Care Unit.

CONCLUSIONS

In our case the young age of the patient and lack of underlying comorbidities initially compensated the severity of the perforation until it became evident from the absent resolution of the pancreatitis. Bearing this in mind, radiological appearances similar to Chilaiditi sign with significant symptoms or signs should be investigated with a CT scan in order to reach promptly a correct diagnosis.

A multimodal Darwinian strategy for alleviating the atherosclerosis pandemic

The conflict between our 'primitive' genes and 'modern' lifestyle probably lies at the root of several disorders that afflict modern man. Atherosclerosis, which is relatively unknown among contemporary hunter-gatherer populations, has reached pandemic proportions in recent times. Being an evolutionary problem with several inter-related pathologies, current therapeutic strategy for treating atherosclerosis has inherent limitations. Reviewing evolution-linked risk factors suggests that there are four aspects to the etiology of atherosclerosis namely, decreased intestinal parasitism, oversensitivity of evolutionarily redundant mast cells, chronic underactivation of AMPK (cellular energy sensor) and a deficiency of vitamin D. A combination of these four causes appear to have precipitated the atherosclerosis pandemic in modern times. Man and worms co-existed symbiotically in the past. Massive de-worming campaigns could have disrupted this symbiosis, increasing nutritional availability to man (pro-obesity) at the cost of decreased immunotolerance (pro-atherogenicity). A reduction in helminth-induced chronic TH2 activation could also have enhanced TH1 polarization, eventually disrupting the reciprocal regulation of TH1/TH2 balance and resulting in atherosclerosis. The riddance of helminth infestations may have rendered mast cells immunologically redundant, making them oversensitive to inflammatory stimuli, thereby playing a pro-atherogenic role. AMPK activation exerts pleiotropic anti-atherogenic effects, such as suppression of fatty acid, cholesterol, protein synthesis, reduction of vascular smooth muscle proliferation, etc. As energy deficit is the chief stimulus for AMPK activation, the over-nourished modern man appears to be suffering from chronic underactivation of AMPK, legitimising the unrivalled supremacy of metformin, the oldest prescribed antidiabetic drug. The fact that humans evolved in the sunny tropics suggests that humans are selected for high vitamin D levels. Vitamin D deficiency is now linked to several conditions including increased risk of CV disorders, diabetes, etc. The manifold decrease in vitamin D levels in modern man justifies a need for supplementation. We therefore hypothesize that a judicious combination of mast cell stabilization, AMPK activation, vitamin D supplementation, and moderation in hygiene practices could be an evolution-based multimodal strategy for both preventing and mitigating the pandemic of atherosclerosis.

Dystroglycan function is a novel determinant of tumor growth and behavior in prostate cancer

BACKGROUND

Dystroglycan is a ubiquitously expressed cell adhesion molecule frequently found to be altered or reduced in adenocarcinomas, however the mechanisms or consequences of dystroglycan loss have not been studied extensively.

METHODS

We examined the consequence of overexpression or RNAi depletion of dystroglycan on properties of in vitro growth migration and invasion of LNCaP, PC3, and DU145 prostate cancer cell lines.

RESULTS

Using LNCaP cells we observed cell density-dependent changes in β-dystroglycan with the appearance of several lower molecular weight species ranging in size from 43 to 26 kDa. The bands of 31 and 26 kDa were attributed to proteolysis, whereas bands between 43 and 38 kDa were a consequence of mis-glycosylation. The localization of β-dystroglycan in LNCaP colonies in culture also varied, cells with a mesenchymal appearance at the periphery of the colony had more pronounced membrane localization of dystroglycan. Whereas some cells demonstrated nuclear dystroglycan. Increased dystroglycan levels were inhibitory to growth in soft agar but promoted Matrigel invasion, whereas reduced dystroglycan levels promoted growth in soft agar but inhibited invasion. Similar results were also obtained for PC3 and DU145 cells.

CONCLUSIONS

This study suggests that changes in β-dystroglycan distribution within the cell and/or the loss of dystroglycan during tumorigenesis, through a combination of proteolysis and altered glycosylation, leads to an increased ability to grow in an anchorage independent manner, however dystroglycan may need to be re-expressed for cell invasion and metastasis to occur.

Benign esophagorespiratory fistula: a case series and a novel technique of definitive management

Benign esophagorespiratory fistula is a relatively rare condition in adults that poses a technical challenge to manage. This case series describes our experience in the treatment of benign esophagorespiratory fistula in 12 adults. A retrospective review of case records of 12 patients with benign esophagorespiratory fistula was done. There were eight tracheoesophageal fistulae and four bronchoesophageal fistulae. Among them, four fistulae were congenital, one was secondary to corrosive injury, three were due to foreign body (dentures), one was secondary to erosion because of prolonged endotracheal intubation, one was secondary to penetrating trauma, and two were infective in etiology. Of the 12 patients, there were nine males and three females. The mean age of presentation was 30.16 years (range 15-53 years). Nine patients had a definitive surgical intervention. The esophageal end of the fistula was managed by primary closure of the esophageal defect and reinforcement with pleural or intercostal muscle flap or a subtotal esophagectomy. The respiratory end of the fistula was dealt with by primary closure of the defect or by a novel technique of neomembranous airway formation, whereby the tracheal defect was closed with the help of a vascularized patch of the esophageal wall. The technique of this neomembranous airway formation is described in detail, and to our knowledge, this is the first time that this technique is being reported in the English literature. This technique is a novel method for definitive repair and can be considered as an option for repair of esophagorespiratory fistula with large defects.

15-lipoxygenase-1 in colorectal cancer: a review

OBJECTIVE

Enzymes involved in the oxidative metabolism of n-6 polyunsaturated fatty acids, like lipoxygenase (LOX) and cyclooxygenase (COX), are significant in the pathogenesis of colorectal cancer. Of these enzymes, 15-LOX-1 is expressed in colon. Aim of this article is to describe the role and regulation of 15-LOX-1 in colorectal cancer and highlight its importance in cancer therapeutics.

METHODS

For our electronic literature research in PubMed and MEDLINE, key words related to 15-LOX-1 and colorectal cancer were used to find articles for this review.

RESULTS

From the evidences, we believe that 15-LOX-1 has anti-carcinogenic effects in colorectal cancer, dependent or independent of its metabolites, and is manifested through downstream pathways involving cGMP, PPAR, p53, p21 and NAG-1, increasing apoptosis and decreasing proliferation in cancer cells. Regulation of 15-LOX-1 expression is achieved at transcription level by global histone acetylation and may also be dependent on GATA-6, IL-4 and IL-13. Positive relationship exists between 15-LOX-1 and survival in colorectal cancer.

CONCLUSION

Evidences strongly support that therapeutic modulation of 15-LOX-1 may be a key to the treatment of colorectal cancer. However, it is still undecided whether the up-regulation of 15-LOX-1 alone can be sufficient to treat colorectal cancer and further studies are awaited.

Octreotide in chemotherapy induced diarrhoea in colorectal cancer: a review article

BACKGROUND

Chemotherapy-induced diarrhoea (CID) is well known in cancer management. The risk is greater when the primary cancer is colorectal. This article aims towards assessing the role of octreotide in CID through an extensive literature search.

METHODS

After searching through PUBMED, MEDLINE and the Cochrane library, only those studies which were published over the last 20 years in English and where at least the majority of the cohort were colorectal patients, were included. Two randomized trials, four non-randomized studies and two case-series publications were thus considered.

RESULTS

It was seen in both the randomized studies, that octreotide had much better outcome as compared to loperamide in treating severe CID. Among 88 patients from the non-randomized studies with severe CID, the primary cancer was colorectal in 79 patients. 61 patients had drug-resistant CID. Within a maximum of 96 hours, octreotide reduced CID by > or = 2 grades in 91% of 88 patients and in 88.52% patients with drug-resistant CID.

CONCLUSION

Octreotide is effective in treating severe CID, resistant to other modes of treatment. It is associated with a few minor adverse effects. Though expensive, octreotide could be considered as first line medication in CID of grades 3 or above. Its use in lower grades of CID would not be cost effective.

Effects of 21 days of bed rest, with or without artificial gravity, on nutritional status of humans

Spaceflight and bed rest models of microgravity have profound effects on physiological systems, including the cardiovascular, musculoskeletal, and immune systems. These effects can be exacerbated by suboptimal nutrient status, and therefore it is critical to monitor nutritional status when evaluating countermeasures to mitigate negative effects of spaceflight. As part of a larger study to investigate the usefulness of artificial gravity as a countermeasure for musculoskeletal and cardiovascular deficits during bed rest, we tested the hypothesis that artificial gravity would have an effect on some aspects of nutritional status. Dietary intake was recorded daily before, during, and after 21 days of bed rest with artificial gravity (n = 8) or bed rest alone (n = 7). We examined body composition, hematology, general blood chemistry, markers of oxidative damage, and blood levels of selected vitamins and minerals before, during, and after the bed rest period. Several indicators of vitamin status changed in response to diet changes: serum alpha- and gamma-tocopherol and urinary 4-pyridoxic acid decreased (P < 0.001) and plasma beta-carotene increased (P < 0.001) in both groups during bed rest compared with before bed rest. A decrease in hematocrit (P < 0.001) after bed rest was accompanied by a decrease in transferrin (P < 0.001), but transferrin receptors were not changed. These data provide evidence that artificial gravity itself does not negatively affect nutritional status during bed rest. Likewise, artificial gravity has no protective effect on nutritional status during bed rest.

Parastomal hernia: Is prevention better than cure? Use of preperitoneal polypropylene mesh at the time of stoma formation

BACKGROUND

This is a prospective study of prophylactic mesh placement in the preperitoneal space at the time of stoma formation to prevent parastomal hernia.

METHODS

Patients undergoing elective permanent stoma formation and resiting of a stoma were included. Patients with peritoneal contamination were excluded. A 6x6-cm polypropylene mesh was placed in the preperitoneal space (no stitches), and a circular hole was made to let the bowel come through with ease and the stoma was constructed. At follow-up, the patients were examined standing and lying down for parastomal hernia. In the event of clinical uncertainty, a CT scan was done.

RESULTS

A total of 42 patients (20 women, 22 men, mean age 61 years) were eligible for the study. The patients were followed up for a mean of 31 months (range 9-68 months). There were 29 end-colostomies and 8 end-ileostomies and 5 stomas resited. Four parastomal hernias were detected during the follow-up period (9.52%). One required repair due to an ill-fitting stoma bag and leakage. The other three were asymptomatic. One patient developed stomal necrosis which required a new segment of bowel to be brought out through the same opening and the underlying mesh was left undisturbed.

CONCLUSIONS

The results of the 2-year follow-up in this study (incidence of parastomal herniation 9.5%) along with available evidence in the literature (incidence 0-8.3%), compared to the results of repair make a strong case for the use of a mesh at the time of initial surgery for the formation of any permanent stoma to prevent parastomal herniation.

Mechanical and Swelling Behavior of Double Networked Natural Rubber Cured Using a New Binary Accelerator System

The concept of double networks, which impart chain orientation to elastomers, is a rather new idea. Double networks were induced in natural rubber vulcanizates cured with different accelerator systems. Double networked natural rubber with different extensions cured with N-cyclohexyl benzothiazyl sulphenamide (CBS) and 1-phenyl 5-ortho -tolyl 2,4 dithiobiuret was studied and the effect of extension on the mechanical properties and swelling was analyzed. The extent of chain orientation was analyzed through anisotropic swelling studies. The modulus, tensile strength and tear strength showed an increase with increased residual extension ratio. The effect was more predominant in the longitudinal direction than in the transverse direction. The ultimate tensile elongation showed a slight deterioration. It was revealed that the formation of double networks with higher residual extension ratios restricted the entry of the solvent. Based on the studies it was concluded that residual extension has a profound effect in determining the final properties of vulcanizates.

Primary splenic flexure volvulus

Primary splenic flexure volvulus is a rare entity. We report an acute presentation of primary splenic flexure volvulus with gangrene in a 24-year-old man. Radiograph showed a massively-dilated large bowel loop with a coffee-bean sign. At emergency laparotomy, a distended and gangrenous splenic flexure was found, with absence of all three ligamentous attachments of the splenic flexure.

Prevention of parastomal hernia using preperitoneal mesh: a prospective observational study

OBJECTIVE

Parastomal hernia is a common complication after stoma formation. The objective of the study was to see whether placing prophylactic preperitoneal mesh could reduce the incidence of parastomal hernia.

METHOD

Patients having elective bowel surgery requiring permanent stoma were included in this study. The time required for mesh insertion, day of stoma function, and early complications were recorded. Follow up was at 6 weeks, 3-monthly for the first year and at 6-monthly intervals thereafter.

RESULTS

Eighteen patients fulfilled the inclusion criteria and were followed up for 6-28 months (mean 16.05). The time taken for mesh placement was 12-22 min (mean 14). One patient had to have revision surgery on day 1 for stomal necrosis - the mesh was left in situ in that instance. This patient developed superficial laparotomy wound infection. During the follow up, no patients developed parastomal hernia, stomal prolapse, stenosis, retraction, fistula or obstruction.

CONCLUSION

The early results, in this group of patients, show that prophylactic polypropylene mesh insertion at the time of permanent stoma formation is encouraging and long-term results are awaited.

A missing denture's misadventure!

We report a late onset, benign, tracheoesophageal fistula in a 51-year-old man, due to an accidentally swallowed denture. In view of the extensive peri-esophageal sepsis and fibrosis, he was managed by a subtotal esophagectomy and a cervical esophagogastric anastomosis. The tracheal defect was closed with the help of an intercostal muscle flap. This report also highlights the difficulty in identifying swallowed prosthetic dental material radiologically, when no metallic component is present. This fact was also responsible for the delay in diagnosis, eventually leading to the rare complication of a tracheoesophageal fistula.

Postoperative mortality following oesophagectomy and problems in reporting its rate

BACKGROUND

There have been three previous reviews of the world literature describing postoperative mortality rate following oesophagectomy. The first documented rates in the first half of the last century, the second the period 1960-1979 and the third the interval 1980-1988. The aim of this review was to document the rate for the period 1990-2000.

METHODS

Reports were sourced through PubMed and/or Medline listings.

RESULTS

The number of papers included in the review was 312, involving 70,756 patients. The overall mortality rate was 6.7 per cent. The 30-day mortality rate was 4.9 per cent and the in-hospital mortality rate 8.8 per cent. Survival rates, where reported, were 62.7 per cent at 1 year and 27.9 per cent at 5 years.

CONCLUSION

Operative mortality rates following oesophagectomy have continued to fall. However, the true rate is almost certainly higher than that reported here, for a variety of reasons. The 1-year survival of patients was only reported in about a quarter of the papers. It may be a more meaningful figure than postoperative mortality rate.