The electrochemical corrosion of pure magnesium in 1 N NaCl

An electrochemical investigation was carried out to study the corrosion of pure magnesium in 1 N NaCl at different pH values involving electrochemical polarisation, scanning tunnel microscopy (STM), measurement of hydrogen gas evolution and measurement of the elements dissolved from the magnesium specimen which were determined by inductively coupled plasma atomic emission spectrophotometry (ICPAES). A partially protective surface film was a principal factor controlling corrosion. Film coverage decreased with increasing applied electrode potential. Application of a suitable external cathodic current density was shown to inhibit magnesium dissolution whilst at the same time the hydrogen evolution rate was relatively small. This showed that cathodic protection could be used to significantly reduce magnesium corrosion. A new definition is proposed for the negative difference effect (NDE). (C) 1997 Elsevier Science Ltd.

A new lipid from an Australian marine sponge, Callyspongia sp.

A specimen of the sponge Callyspongia sp. collected off the coast of New South Wales, Australia, has yielded the novel lipid (6Z,9Z,12Z,15Z)-1, 6, 9, 12, 15-octadecapenten-3-one, together with (4Z,7Z,10Z,13Z)-4, 7, 10, 13-hexadecatetraenoic acid.

Laboratory wear testing of polyurethane elastomers

A dry sand-rubber wheel abrasion test was used to investigate the wear behaviour of polyurethanes. The dry sand-rubber wheel abrasion test (DSRW test) is an approved ASTM test designed primarily for testing metals, therefore, in this study the set of test conditions was optimized for use with polyurethane elastomers. The wear performance of polyurethanes was assessed for the range of Shore hardness 85A to 65D, and a correlation was identified between the wear rate and the sample hardness. Polyurethane elastomers can be separated into three classes according to their hardness and wear performance, and each class shows a different dependence on the specimen temperature. This work has implications for use of the DSRW test for the prediction of field performance of polyurethanes. (C) Elsevier Science S.A.

Inflammatory epidermolysis bullosa acquisita - Case report

We report a case of an inflammatory variant of epidermolysis bullosa acquisita in a 53-year-old male, with itching blistering eruption on the trunk, armpits and limbs for six months. The skin biopsy specimen showed subepidermal blister with neutrophils. Direct immunofluorescence revealed linear depositions of IgG, IgA, IgM and C3 at the basement membrane; indirect immunofluorescence and salt split skin were negative. Antinuclear antibodies were also negative. Improvement of the blisters followed treatment with systemic corticotherapy and some lesions healed with milia. This is a rare presentation of epidermolysis bullosa acquisita, with inflammatory lesions at first.

Erythema elevatum diutinum presenting with a giant annular pattern

A 45-year-old woman presented with a 3-year history of cutaneous lesions. Clinical examination revealed red-yellow to brownish infiltrated papules coalescing into annular-shaped plaques of several sizes with a hyperpigmented center affecting the abdomen and lower limbs, as well as multiple firm nodules on the right palm, elbows, and knees (Fig. 1a-c). The patient also reported sporadic arthralgia and low fever. She had been treated for leprosy for 2 years with multidrug therapy (clofazimine, dapsone, and rifampicin), with complete remission of the lesions during treatment, but recurrence after discontinuation. Histologic examination of a biopsy specimen taken from the cutaneous lesions showed an interstitial inflammatory infiltrate with the presence of many neutrophils and occasional foamy histiocytes (Fig. 2a). A pattern of perivascular eosinophilic fibrosis was observed in a biopsy specimen from a nodule (Fig. 2b). Special stains for acid-fast bacilli and fungi were negative. Laboratory findings included elevated immunoglobulin A (IgA) serum levels (1016 mg/dL; normal range, 69-382 mg/dL), elevated beta-globulin, and strong tuberculin reactivity. Normal or negative tests included direct immunofluorescence, serum immunofixation, anti-streptolysin O, and chest radiography. Autoimmune disorders and inflammatory intestinal diseases were excluded. The patient was treated with dapsone, 100 mg/day, with great improvement of the clinical picture. Hyperpigmented residual macules and some fibrotic nodules remained after 3 months.

Rectal and Pouch Recurrences After Surgical Treatment for Familial Adenomatous Polyposis

Familial adenomatous polyposis (FAP) is a genetic disease characterized by multiple adenomatous colorectal polyps and different extracolonic manifestations (ECM). The present work is aimed to analyze the outcome after surgical treatment regarding complications and cancer recurrence. Charts from patients treated between 1977 and 2006 were retrospectively analyzed. Clinical and endoscopic data, results of treatment, pathological reports and information about recurrence were collected. Eighty-eight patients (41 men [46.6%] and 47 women [53.4%]) were assisted. At diagnosis, associated colorectal cancer (CRC) was detected in 53 patients (60.2%), whose average age was higher than those without CRC (40.0 vs. 29.5 years). At colonoscopy, polyposis was classified as attenuated in 12 patients (14.3%). Surgical treatment consisted in total proctocolectomy with ileostomy (PCI, 15 [17.4%]), restorative proctocolectomy (RPC, 27 [31.4%]), total colectomy with ileal-rectum anastomosis (IRA, 42 [48.8%]), palliative segmental resection (1 [1.2%]) and internal bypass (1 [1.2%]). Two patients were not operated on due to religious reasons and advanced disease. Complications occurred in 25 patients (29.0%), more commonly after RPC (48.1%). There was no operative mortality. Local or distant metastases were detected in six (11.3%) patients with CRC treated to cure. During the follow-up of 36 IRA, cancer developed in the rectal cuff in six patients (16.6%), whose average age was higher than in patients without rectal recurrence (45.8 vs. 36.6 years). Five of them have had colonic cancer in the resected specimen. Among the 26 patients followed after RPC, cancer in the ileal pouch developed in 1 (3.8%). (1) Within the present series, FAP patients presented a high incidence of associated CRC and diagnosis was generally established after the third decade of life; (2) operative complications occurred in about one third of the patients, being more frequent after the confection of an ileal reservoir; (3) rectal cancer after IRA was detected in 16.6% of patients and it was associated with greater age and previous colonic carcinoma; (4) both continuous and long-term surveillance of the rectal stump and ileal pouch are necessary during follow-up.

Laparoscopic right hemihepatectomy for hepatolithiasis

Background Liver resection is the definitive treatment for unilateral hepatolithiasis [1]. Recently, laparoscopic major hepatectomias have become more common and are being performed in highly specialized centers [2-4]. However, few laparoscopic liver resections for hepatolithiasis have been reported. Chen et al. [5] reported two cases of laparoscopic left lobectomy for hepatolithiasis, but to our knowledge, right hepatectomy has never been reported to date. This video demonstrates technical aspects of a totally laparoscopic right hepatectomy in a patient with hepatolithiasis. Methods A 21-year-old woman with right-sided nonoriental primary intrahepatic stones [1] was referred for surgical treatment. The operation followed four distinct phases: liver mobilization, dissection of the right portal vein and right hepatic artery, extrahepatic dissection of the right hepatic vein, and parenchymal transection with harmonic shears and linear staplers for division of segment 5 and 8 branches of the middle hepatic vein. No Pringles` maneuver was used. In contrast to liver resection for other indications, the right bile duct was enlarged and filled with stones. It was divided during parenchymal transection and left open. After removal of the surgical specimen, the biliary tree was flushed with saline until stone clearance, under radioscopic surveillance, was complete. The right hepatic duct then was closed with running suture. Results The operative time was 240 min, and the estimated blood loss was 120 ml, with no blood transfusion. The hospital stay was 5 days. At this writing, the patient is well and asymptomatic 7 months after the procedure. Conclusion Laparoscopic liver resection is safe and feasible for patients with hepatolithiasis and should be considered for those suffering from intrahepatic stones.

Case Report: Severe Rhabdomyolysis Caused by Plasmodium vivax Malaria in the Brazilian Amazon

Severe rhabdomyolysis (creatine phosphokinase = 29.400U/L) developed in a 16-year-old boy from Manaus. Brazil, after he started treatment with chloroquine for infection with Plasmodium vivax Treatment led to myoglobinuria and acute renal failure After hemodialysis. the patient improved and a muscle biopsy specimen showed no myophosphorylase or deaminase deficiency. This case of rhabdomyolysis associated with P vivax infection showed no comorbidities The pathogenesis is still unclear

Hodgkin`s Lymphoma Presenting as Dominant Gastric Lesion in Immunocompetent Patients: Report of 5 Cases With EBV Analysis

Primary Hodgkin`s lymphoma (HL) of the stomach is an extremely rare entity. Most cases of gastric involvement by HL are observed in the setting of disseminated disease. The nonspecific nature of the symptoms and endoscopic findings, which include a large malignant-looking ulcer and mass or wall thickening, together with the considerable histological overlap between HLs and some non-HLs or undifferentiated carcinoma, make the surgical resection diagnosis extremely difficult. An accurate diagnosis is important as treatment and outcome differ significantly for these neoplasms. In small endoscopic gastric biopsies and even in postoperative specimens, the precise histological diagnosis of HL is particularly challenging. Here, the authors report 5 cases of 2 women and 3 men aged 22 to 68, with gastric involvement by classic HLs-3 primary gastric HLs and 2 as part of widespread disease. All 5 patients presented with digestive symptoms. At endoscopy, the lesions presented as ulcerated and elevated lesions, with or without mucosal thickening. Four patients were misdiagnosed in the preoperative biopsy or in the gastrectomy specimen. Association with Epstein-Barr virus (EBV) was detected in 4 cases, with a predominance of subtype A EBV. These cases illustrate the significant difficulties, both clinical and pathological, in achieving the diagnosis of HL involving the stomach in immunocompetent patients.

Submucosal Injection of 0.4% Hydroxypropyl Methylcellulose Facilitates Endoscopic Mucosal Resection of Early Gastrointestinal Tumors

Background and Aims: Submucosal injection of a viscoelastic solution prolongs submucosal lift, thus, facilitating endoscopic mucosal resection. Our objective was to assess the safety and clinical effectiveness of 0.4% hydroxypropyl methylcellulose (HPMC) as a submucosal injectant for endoscopic mucosal resection. Patients and Methods: A prospective, open-label, multicenter, phase 2 study was conducted at 2 academic institutions in Brazil. Eligible participants included patients with early gastrointestinal tumors larger than 10 mm. Outcomes evaluated included complete resection rates, volume of HPMC injected, duration of the submucosal cushion as assessed visually, histology of the resected leisons, and complication rates. Results: Over a 12-month period, 36 eligible patients with superficial neoplastic lesions (stomach 14, colon 11, rectum 5, esophagus 3, duodenum 3) were prospectively enrolled in the study. The mean size of the resected specimen was 20.4 mm (10 to 60 mm). The mean volume of 0.4% HPMC injected was 10.7 mL (range 4 to 35 mL). The mean duration of the submucosal fluid cushion was 27 minutes (range 9 to 70 min). Complete resection was successfully completed in 89%. Five patients (14%) developed immediate bleeding requiring endoclip and APC application. Esophageal perforation occurred in 1 patient requiring surgical intervention. There were no local or systemic adverse events related to HPMC use over the follow-up period (mean 2.2 mo). Conclusion: HPMC solution (0.4%) provides an effective submucosal fluid cushion and is safe for endoscopic resection of early gastrointestinal neoplastic lesions.

Predictive Factors for Positive Surgical Margins and Their Locations After Robot-Assisted Laparoscopic Radical Prostatectomy

Background: Positive surgical margin (PSM) after radical prostatectomy (RP) has been shown to be an independent predictive factor for cancer recurrence. Several investigations have correlated clinical and histopathologic findings with surgical margin status after open RP. However, few studies have addressed the predictive factors for PSM after robot-assisted laparoscopic RP (RARP). Objective: We sought to identify predictive factors for PSMs and their locations after RARP. Design, setting, and participants: We prospectively analyzed 876 consecutive patients who underwent RARP from January 2008 to May 2009. Intervention: All patients underwent RARP performed by a single surgeon with previous experience of > 1500 cases. Measurements: Stepwise logistic regression was used to identify potential predictive factors for PSM. Three logistic regression models were built: (1) one using preoperative variables only, (2) another using all variables (preoperative, intraoperative, and postoperative) combined, and (3) one created to identify potential predictive factors for PSM location. Preoperative variables entered into the models included age, body mass index (BMI), prostate-specific antigen, clinical stage, number of positive cores, percentage of positive cores, and American Urological Association symptom score. Intra-and postoperative variables analyzed were type of nerve sparing, presence of median lobe, percentage of tumor in the surgical specimen, gland size, histopathologic findings, pathologic stage, and pathologic Gleason grade. Results and limitations: In the multivariable analysis including preoperative variables, clinical stage was the only independent predictive factor for PSM, with a higher PSM rate for T3 versus T1c (odds ratio [OR]: 10.7; 95% confidence interval [CI], 2.6-43.8) and for T2 versus T1c (OR: 2.9; 95% CI, 1.9-4.6). Considering pre-, intra-, and postoperative variables combined, percentage of tumor, pathologic stage, and pathologic Gleason score were associated with increased risk of PSM in the univariable analysis (p < 0.001 for all variables). However, in the multivariable analysis, pathologic stage (pT2 vs pT1; OR: 2.9; 95% CI, 1.9-4.6) and percentage of tumor in the surgical specimen (OR: 8.7; 95% CI, 2.2-34.5; p = 0.0022) were the only independent predictive factors for PSM. Finally, BMI was shown to be an independent predictive factor(OR: 1.1; 95% CI, 1.0-1.3; p = 0.0119) for apical PSMs, with increasing BMI predicting higher incidence of apex location. Because most of our patients were referred from other centers, the biopsy technique and the number of cores were not standardized in our series. Conclusions: Clinical stage was the only preoperative variable independently associated with PSM after RARP. Pathologic stage and percentage of tumor in the surgical specimen were identified as independent predictive factors for PSMs when analyzing pre-, intra-, and postoperative variables combined. BMI was shown to be an independent predictive factor for apical PSMs. (C) 2010 European Association of Urology. Published by Elsevier B. V. All rights reserved.

Evolution of Laparoscopic Colorectal Surgery in Brazil Results of 4744 Patients From the National Registry

Background: Since its introduction, laparoscopic colorectal surgery has raised intense debate and controversies regarding its safety and effectiveness. Methods: This multicentric registry reports the experience of 28 Brazilian surgical teams specializing in laparoscopic colorectal surgery. Results: Between 1992 and 2007, 4744 patients (1994 men-42% and 2750 women-58%) were operated upon, with ages ranging from 13 to 94 years (average 57.5y). Benign diseases were diagnosed in 2356 patients (49.6%). Most diseases were located in 50.7% of the left and sigmoid colon, 28.2% in the rectum and anal canal. 8.0% in the right colon, and diffuse 7.0%. There were 181 (3.8%) intraoperative complications (from 0% to 14%). There were 261 (5.5%) reported conversions to laparotomy (from 0% to 16.5%), mainly during the early experience (n = 119 - 59.8%). Postoperative complications were registered in 683 (14.5%) patients (from 5.0% to 50%). Mortality occurred in 43 patients (0.8%). Surgeons who performed less than 50 cases reported similar rates of intraoperative (4.2% vs. 3.8%,- P = 0.7), postoperative complications (20.8% vs. 14.3%; P = 0.07), and mortality (1.0% vs. 0.9%; P = 0.5) but the conversion rate was higher (10.4% vs. 5.4%; P = 0.04). Two thousand three hundred and eighty-nine (50.4%) malignant tumors were operated upon, and histologic classification showed 2347 (98%) adenocarcinomas, 30 (0.6%) spinocelular carcinomas, and 12 (0.2%) other histologic types. Tumor recurrence rate was 16.3% among patients followed more than I year. After an average follow-Lip of 52 months, 19 (0.8%) parietal recurrences were reported, 18 of which were in port sites and I in a patient with disseminated disease. There was no incisional recurrence in the ports used to withdraw the pathologic specimen. Compared with other registries, there was a 75% increase in the number of groups pet-forming laparoscopic colorectal surgery and a decrease in conversions (from 10.5%. to 5.5%) and mortality (from 1.5% to 0.9%) rates. Conclusions: (1) The number of patients operated upon increased expressively during the last years; (2) operative indications for benign and malignant diseases were similar, and diverticular disease of the colon comprised 40% of the benign ones; (3) conversion and mortality rates decreased over time; (4) Surgeon`s experience did not influence the complication rates, but was associated with a lower conversion; and (5) oncologic outcome expressed by recurrence rates showed results similar to those reported in conventional surgery.

Laparoscopic resection of uncinate process of the pancreas

Solid pseudopapillary neoplasm of the pancreas is an uncommon but distinctive pancreatic neoplasm with low metastatic potential [1]. Therefore, whenever feasible, an organ-preserving operation should be performed. As previously reported, women with solid pseudopapillary neoplasm of the pancreas may be best treated by more conservative procedures [2]. Recently, laparoscopic pancreatic resections became more common and are being performed in highly specialized centers. There are only six cases of laparoscopic resection for solid pseudopapillary neoplasm of pancreas published in the English literature and, to our knowledge, laparoscopic resection of uncinate process of the pancreas has never been reported [3-6]. This video demonstrates the technical aspects of a totally laparoscopic resection of the uncinate process of the pancreas in a patient with solid pseudopapillary neoplasm. A 26-year-old woman with a 4-cm solid pseudopapillary pancreatic neoplasm was referred for surgical treatment. According to preoperative echoendoscopy, there was a safe margin between neoplasm and main pancreatic duct. The patient was placed in supine position with the surgeon standing between her legs. Four trocars, one 10-mm and three 5-mm, were used. At inspection, the inferior vena cava, transverse colon, duodenum, and pancreas are clearly identified. A Kocher maneuver was performed with complete exposure of pancreatic head and uncinate process. The uncinate process was dissected from the superior mesenteric vein and venous branches were divided between metallic clips or by use of laparoscopic coagulation shears (LCS; Ethicon Endo Surgery Industries, Cincinnati, OH, USA). Blood supply of the duodenum was preserved by ligature of small pancreatic branches from inferior pancreatoduodenal artery. Transection of pancreatic parenchyma was performed using laparoscopic coagulation shears, which is an effective tool for cutting the pancreas [7, 8]. Surgical specimen was removed through a suprapubic incision inside a retrieval bag. A hemostatic absorbable tissue (Surgicel; Ethicon Inc., Cincinnati, OH) was placed in the cutting pancreatic surface, and one round 19F Blake abdominal drain (Ethicon) was left in place. Operative time was 180 minutes and blood loss estimated in 40 ml with no blood transfusion. Hospital stay was 4 days. The patient did not have postoperative pancreatitis or pancreatic leakage, and the abdominal drain was removed on the tenth postoperative day. Final pathology confirmed the diagnosis of solid pseudopapillary neoplasm of pancreas with free surgical margins. The patient was well and asymptomatic 2 months after the procedure. Laparoscopic resection of uncinate process of the pancreas is safe and feasible and should be considered for patients suffering from pancreatic neoplasms.

Eruptive xanthoma with unexpected granuloma annulare-like microscopic appearance - Case report

Eruptive xanthoma with unexpected granuloma annulare-like microscopic appearance - Case report Abstract: Eruptive xanthoma and granuloma annulare are dermatological diseases with different clinical findings that, sometimes, exhibit histopathological similarities with potential for misinterpretation. We report a case of an eruption of yellow-orange papules with erythematous borders in a 34-year-old male with high levels of serum triglycerides and cholesterol. The skin biopsy specimen has diagnosed granuloma annulare. Review of the histologic material revealed eruptive xanthoma. Remission of the eruption after treatment of dyslipidemia confirmed the diagnosis of the eruptive xanthoma and motivated research about the histological similarities and differences between these diseases.

A Simple Technique for Large Tumor Removal During Laparoscopic Liver Resection

Experience with laparoscopic liver resections has increased in recent years, and so have the number of patients operated on by minimally invasive techniques. Specimen extraction is an important step of laparoscopic liver resection. The size of the specimen, is Usually a limitation for the use Of laparoscopy. The aim of this paper is to describe a new technique combining Pfannenstiel suprapubic incision and obstetric forceps to remove a large specimen from laparoscopic liver resections. The present technique allows an expeditious extraction of intact specimens, even huge ones, through a standard suprapubic Pfannenstiel incision. This technique has additional functional and cosmetic advantages over other techniques of specimen retrieval. We believe that the described technique is feasible, can be easily and rapidly performed, and facilitates laparoscopic liver resection by reducing the technical difficulties for specimen removal and may also be used in other abdominal laparoscopic interventions that deal with large surgical specimens.