Chronic gastritis and Helicobacter pylori: a histopathological study of gastric mucosal biopsies

The aim of this study was to observe the histological features of chronic gastritis and associated effects due to Helicobacter pylori infection in 176 randomly selected antral biopsy specimens of chronic gastritis cases. The specimens were reviewed for the presence or absence of H.pylori. The activity (neutrophilic infiltration) of gastritis and the presence or absence of mucosa-associated lymphoid tissue (MALT) were also noted. Chi-square test (Pearson value) was used to analyze categorical variables. H.pylori was detected in 110 (62.5%) cases of chronic gastritis. There was a significant association between H.pylori infection and activity of chronic gastritis (p=0.002). Lymphoid aggregates were significantly more frequently noted in H.pylori-positive patients (68.2%) vs. H.pylori negative group (47%), (p=0.005). It is concluded that H.pylori is significantly associated with active chronic gastritis and with formation of mucosa-associated lymphoid tissue (MALT), which may develop into gastric lymphoma (MALT type).     

Ruptured AAA: open surgical management

Ruptured abdominal aorta aneurysm (rAAA) is the 13th leading cause of death in the United States. Despite many advances in the field of vascular surgery, the improvement in mortality rates of rAAA have been very modest. Although endovascular repair has surpassed open repair for elective AAA repair in the United States, open rAAA repair remains the most common therapy for this devastating vascular emergency. In this article, we discuss open surgical management for rAAA. We also describe a fast-track algorithm we have developed at the University of Massachusetts where open and endovascular repairs play equally important roles in management of rAAA.     

Involvement of nitric oxide pathway in the acute anticonvulsant effect of melatonin in mice

Melatonin, the major hormone produced by the pineal gland, is shown to have anticonvulsant effects. Nitric oxide (NO) is a known mediator in seizure susceptibility modulation. In the present study, the involvement of NO pathway in the anticonvulsant effect of melatonin in pentylenetetrazole (PTZ)-induced clonic seizures was investigated in mice. Acute intraperitoneal administration of melatonin (40 and 80 mg/kg) significantly increased the clonic seizure threshold induced by intravenous administration of PTZ. This effect was observed as soon as 1 min after injection and lasted for 30 min with a peak effect at 3 min after melatonin administration. Combination of per se non-effective doses of melatonin (10 and 20 mg/kg) and nitric oxide synthase (NOS) substrate L-arginine (30, 60 mg/kg) showed a significant anticonvulsant activity. This effect was reversed by NOS inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME, 30 mg/kg), implying an NO-dependent mechanism for melatonin effect. Pretreatment with L-NAME (30 mg/kg) and N(G)-nitro-L-arginine (L-NNA, 10 mg/kg) inhibited the anticonvulsant property of melatonin (40 and 80 mg/kg) and melatonin 40 mg/kg, respectively. Specific inducible NOS (iNOS) inhibitor aminoguanidine (100 and 300 mg/kg) did not affect the anticonvulsant effect of melatonin, excluding the role of iNOS in this phenomenon, while pretreatment of with 7-NI (50 mg/kg), a preferential neuronal NOS inhibitor, reversed this effect. The present data show an anticonvulsant effect for melatonin in i.v. PTZ seizure paradigm, which may be mediated via NO/L-arginine pathway by constitutively expressed NOS.     

Comparison of dapoxetine versus paroxetine in patients with premature ejaculation: a double-blind, placebo-controlled, fixed-dose, randomized study

PURPOSE: To compare the efficacy and safety of dapoxetine, paroxetine, and placebo for the oral pharmacotherapy of premature ejaculation. MATERIALS AND METHODS: Three hundred forty potent men with premature ejaculation were recruited to this study. Patients were randomly assigned to receive 60 mg dapoxetine (group 1, n = 115), or 20 mg paroxetine (group 2, n = 113) or placebo (group 3, n = 112) orally daily during a 12-week period for each agent. The efficacy of the 3 treatments was assessed every 2 weeks during treatment and at the end of study using responses to International Index of Erectile Function (IIEF), intravaginal ejaculatory latency time (IELT) evaluation, mean intercourse satisfaction domain, mean weekly coitus episodes and adverse drug effects. RESULTS: At the end of the 12-week treatment with dapoxetine, paroxetine, and placebo, the mean IELT was increased from 38, 31 and 34 seconds to 179, 370 and 55 seconds, respectively (P = 0.01 in group 1 and P = 0.001 in group 2). Baseline mean intercourse satisfaction domain values of International Index of Erectile Function of 10, 11, and 11 reached 14, 17 and 12 at the end of the 12-week treatment in groups 1, 2, and 3 respectively (P = 0.03 in groups 1, 2). The mean weekly intercourse episodes increased from pretreatment values of 1.4, 1.3, and 1.3 to 2.2, 2.5 and 1.4, for dapoxetine, paroxetine and placebo, respectively (P = 0.04 in groups 1, 2). The incidence of adverse effects with dapoxetine and paroxetine was significantly higher (P = 0.04 in groups 1, 2) compared to that of placebo. CONCLUSIONS: Paroxetine appears to provide significantly better results in terms of IELT and intercourse satisfaction versus dapoxetine. Each treatment was well tolerated.     

Dexamethasone mimics the inhibitory effect of chronic pain on the development of tolerance to morphine analgesia and compensates for morphine induced changes in G proteins gene expression

It is previously reported that the HPA axis plays role in the inhibitory effect of pain on tolerance development to analgesic effect of opioids. The present study was designed to investigate whether the chronic co-administration of dexamethasone as a glucocorticoid is also able to prevent or reverse analgesic tolerance to morphine and to compare the expression of G(alphai/o) and G(beta) subunits of G proteins in the context of chronic dexamethasone, development of morphine tolerance and their combination. Analgesic tolerance to morphine was induced by chronic intraperitoneally (i.p.) administration of morphine 20 mg/kg to male Wistar rats weighing 200-240 g within 4 consecutive days and analgesia was assessed using tail-flick test. Chronic dexamethasone was applied using 4 daily i.p. injections. Lumbar spinal tissues were assayed for the expression of G(alphai/o) and G(beta) proteins using "semiquantitative PCR" normalized to beta-actin gene expression. Results showed that chronic administration of dexamethasone could reduce and reverse the development of tolerance in rats that received chronic i.p. injections of morphine. Chronic administration of dexamethasone significantly increased the expression of G(alphai/o), while chronic administration of morphine did not change its expression. The expression of G(beta), however, was increased after the chronic administration of morphine, but did not change after the administration of chronic dexamethasone. None of these increases were observed when morphine and dexamethasone were co-administered. We conclude that the development of tolerance to analgesic effect of morphine could be prevented and reversed by dexamethasone co-administration. The increase in G(alphai/o) genes expression produced by chronic dexamethasone may facilitate the opioid signaling pathway and compensate for morphine-induced tolerance.     

Modified retro-tubercle opening-wedge versus conventional high tibial osteotomy

Despite the fact that common surgical techniques for the treatment of genu varum usually correct the malalignment in the affected knee, these methods have significant complications and cause problems in the long term. Retro-tubercle opening-wedge high tibial osteotomy is among the newer techniques for the treatment of genu varum. The goal of this study was to compare the results of retro-tubercle opening-wedge high tibial osteotomy with those of medial opening-wedge osteotomy. In a randomized, controlled trial, 72 patients with varus knees who were scheduled for surgery were assigned into either the retro-tubercle opening-wedge high tibial osteotomy (n=34) or medial opening-wedge osteotomy groups (n=38). Groups were matched for age and sex. The position of the patella was compared with respect to the tuberosity and the upper tibial slope pre- and postoperatively. Patients were followed for an average of 13 months (range, 10-21 months). In the retro-tubercle opening-wedge high tibial osteotomy group, the length of the patellar tendon did not significantly differ pre- and postoperatively (P≥.5); however, in the medial opening-wedge osteotomy group, a statistically significant shortening was noted in patellar tendon postoperatively (P≤.05). Similarly, the tibial plateau inclination showed a statistically significant difference postoperatively in the medial opening-wedge osteotomy group, while the difference in the retro-tubercle opening-wedge high tibial osteotomy group did not reach statistical significance.     

Is Weight Loss Better Sustained with Long-Limb Gastric Bypass in the Super-Obese?

Background  

While some studies have shown that long-limb gastric bypass with Roux limb length of 150 to 200 cm can attain better weight loss outcomes in super-obese patients (BMI >50 kg/m²) than the standard limb gastric bypass with Roux limb length of 100 to 150 cm, other studies have not shown similar findings. Additionally, no study has demonstrated the optimal length of the Roux limb that will result in ideal weight loss. The purpose of this study is to compare the long-term weight loss and weight regain of standard limb length (SLL) and long limb length (LLL) gastric bypass in patients with BMI >50 kg/m².     

Revision of Failed Bariatric Procedures to Roux-en-Y Gastric Bypass (RYGB)

Bariatric surgery for morbid obesity has been established as an effective treatment method and has been shown to be associated with resolution of co-morbidities. Despite its success, some patients may require revision because of weight regain or mechanical complications. From September 2005 to December 2009, 42 patients underwent revisional Roux-en-Y gastric bypass (RYGB). All procedures were performed by one surgeon. Demographics, indications for revision, complications, and weight loss were reviewed. Thirty-seven patients were treated with laparoscopic (n = 36) or open (n = 1) RYGB after failed laparoscopic adjustable gastric banding. Four patient were treated with laparoscopic (n = 3) or open (n-1) RYGB after failed vertical banded gastroplasty, and one patient underwent open redo RYGB due to large gastric pouch. Conversion rate from laparoscopy to open surgery was 2.5% (one patient). Mean operative time was 145.83 ± 35.19 min, and hospital stay was 3.36 ± 1.20 days. There was no mortality. Early and late complications occurred in six patients (14.2%). The mean follow-up was 15.83 ± 13.43 months. Mean preoperative body mass index was 45.15 ± 7.95 that decreased to 35.23 ± 6.7, and mean percentage excess weight loss was 41.19 ± 20.22 after RYGB within our follow-up period. RYGB as a revisional bariatric procedure is effective to treat complications of restrictive procedures and to further reduce weight in morbidly obese patients.     

Study of short-pulse laser propagation in biological tissue by means of the boundary element method

Propagation of short pulses of light through biological tissues can be studied by numerically solving the diffusion equation. The boundary integral method was used to convert the differential equation to integral form and the result was solved using the boundary element method. The effects of different optical parameters of the tissue, i.e. scattering, absorption coefficients and anisotropic factor, on temporal evolution of the diffusely reflected pulse were studied. The results were compared with those obtained using the finite difference time domain method and the boundary integral method was found to be more precise and faster than the last method. The method can be used to investigate reflected pulses in the study of cell morphology and tumours in different types of tissue.