Sewage contamination in a tropical coastal area (São Sebastião Channel, SP, Brazil).

Urban effluent discharges in Brazilian coastal areas are a chronic problem and often lead to changes in the quality of the marine environment. São-Sebastião-Channel (SSC) is an important aquatic ecosystem to be monitored for urban sewage contamination due to the intense urban activities in that region, as well as the relative high biodiversity of marine organisms. In the area are present three submarine sewage outfalls, a commercial harbour and also the biggest oil terminal in Brazil. Total organic carbon (TOC), total nitrogen (TN), total sulphur (TS), steroids and linear alkylbenzenes (LABs) were measured in sediment samples collected in three strategic locations of the SSC in order to monitor urban sewage contamination. Total LAB and total sterols levels ranged from below DL-51.3 ng g(-1) and below DL-10.40 µg g(-1), respectively. Samples collected near sewage outfall in the central part of the SSC had higher concentrations of urban sewage-associated contaminants.

Time-frequency visualization of alcohol withdrawal tremors.

In this paper, we propose a signal processing method of assessing the severity tremors caused by alcohol withdrawal (AW) syndrome. We have developed an iOS application to calculate the Clinical Institute Withdrawal Assessment (CIWA) score which captures iPod movements using the built-in accelerometer in order to reliably estimate the tremor severity component of the score. We report on the characteristics of AW tremor, the accuracy of electronic assessment of tremor compared to expert clinician assessment, and the potential for using signal processing assessment to differentiate factitious from real tremor in patients seen in the emergency department, as well as in nurses mimicking a tremor. Our preliminary results are based on 84 recordings from 61 subjects (49 patients, 12 nurses). In general we found a linear relationship between energy measured by the accelerometer (in the 4.4-10 Hz range) and the expert rating of tremor severity. Additionally, we demonstrate that 75% of the recordings from patients with actual AW syndrome had a mean peak frequency higher than 7 Hz whereas only 17% of the nurses' factitious tremors were above 7 Hz, suggesting that tremor above 7 Hz could be a potential discriminator of real versus factitious tremors.

Micrometastasis in regional lymph nodes of extirpated colorectal carcinoma: immunohistochemical study using anti-cytokeratin antibodies AE1/AE3.

OBJECTIVE: The main objectives of this study were to identify, by immunohistochemistry, possible micrometastasis in the regional lymph nodes previously considered free by conventional histopathological examination, and to assess their influence on the survival of patients with colorectal cancer that had been extirpated in a radical manner. PATIENTS AND METHODS: From 38 patients with Dukes B staging (Colorectal Carcinoma Stage II (T3 N0 M0 or T4 N0 M0)) colorectal carcinoma, 383 lymph nodes were studied in paraffin blocks that had previously been considered free by conventional histopathological examination. These were submitted to immunohistochemical study using AE1/AE3 anti-cytokeratin monoclonal antibodies to identify neoplastic epithelial cells. RESULTS: Seven lymph nodes (1.82%) in six patients (15.78%) contained micrometastasis. The survival of the patients with extirpated colorectal carcinoma staged as Dukes B who had lymph node metastasis was less than in the group of patients without micrometastasis, although these values were not statistically significant. CONCLUSION: This immunohistochemical method can be employed successfully in the detection of neoplastic cells in lymph nodes previously considered free. In this study, there was a trend towards lower survival in node-positive patients but this did not reach statistical significance.

[Acute pancreatitis due to intramural hematoma of the duodenum by the use of anticoagulants]. / Pancreatite aguda devida a hematoma intramural do duodeno por uso de anticoagulante.

BACKGROUND: Spontaneous intramural hemorrhage of the duodenum due to anticoagulant therapy is rare and the treatment is controversial. OBJECTIVE: To present the acquired knowledge with the treatment of these disease. CASE REPORT: A 71-year-old women receiving for a 3 month period an anticoagulant therapy presented cervical bleeding of soft tissues and symptoms of acute pancreatitis and high small bowel obstruction. Early noninvasive diagnosis by computed tomographic scan was possible and conservative therapy proved successful in complete resolution of the pancreatitis and obstructive symptoms, with resumption of oral intake in the fourth day of treatment. The frequency of bleeding in high risk patients during warfarin therapy is reduced by less intense therapy, achieving a prothrombin time with an International Normalized Ratio of 2.0 to 3.0. RESULTS: The use of conservative treatment was helpful and the patient was discharged asymptomatic, 10 days after admission. CONCLUSION: It is suggested conservative treatment for intramural hematoma of the duodenum and recommended laparotomy only when complications occur.

[Isolated ileocecal tuberculosis simulating malignant neoplasia and Crohn's disease]. / Tuberculose ileocecal isolada simulando neoplasia maligna e doença de Crohn.

BACKGROUND: Isolated ileocecal involvement by tuberculosis in the absence of pulmonar disease is rare in Brasil, therefore causes a diagnostic dilemma as it mimics colonic malignancy and Crohn's disease. METHODS: Between 1969 and 1989, eight patients with isolated hypertrophic ileocecal tuberculosis were treated by surgery in the Gastroenterology Surgery Department of the HSPE-FMO. The most common complaint among them was abdominal pain (100%) with associated symptoms of weight loss (62.5%); nausea, vomiting, fever and general weekness appeared in half of the patients. A right iliac fossa mass was present in seven (87.5% ) of them. The mean duration of symptoms was 14.7 month (range 5-36 months). In all eight patients chest x-rays were negative for tuberculosis. Barium contrast studies showed abnormalities in all cases, but these could not be distinguished from carcinoma. Colonoscopy was helpful in establishing the diagnosis of suboclusive lesions of the ileocecal regions in three patients. Tuberculosis diagnosis was suspected in two of them because ofr the presence of granulomas in colonic biopsy material. RESULTS: Six patients were submitted to elective right hemicolectomy. The two remaining with suspect of tuberculosis were operated with signals of intestinal occlusion, and underwent a limited ileocaecal resection. The positive diagnosis of intestinal tuberculosis was made in all the patients by identification of acid-fast bacilli and by the presence of caseating granulomas in intestinal or lymph node tissue on histological examination. The outcome in all of them was favorable. They received treatment with three antituberculosis drugs over a twelve month period. CONCLUSION: Hypertrophic ileocecal tuberculosis must still be considered in the differential diagnosis of abdominal pathology localized in the right lower quadrant.

Tuberculose ileocecal isolada simulando neoplasia maligna e doença de Crohn / Isolated ileocecal tuberculosis simulating malignant neoplasia and Crohn's disease

OBJETIVO: No Brasil, a tuberculose ileocecal isolada, na ausência de tuberculose pulmonar ativa ou cicatrizada, é rara, sendo freqüentemente confundida com neoplasia e a doença de Crohn. MÉTODOS: Os autores apresentam oito doentes com essas características, tratados por cirurgia, em período de 20 anos. A dor abdominal na fossa ilíaca direita foi o principal sintoma (100 por cento), seguido da presença de perda de peso (62,5 por cento), febre, náuseas e vômitos e fadiga em 50 por cento dos doentes. Sete enfermos (87,5 por cento) apresentaram massa palpável na fossa ilíaca direita. A duraçäo média dos sintomas foi de 14,7 meses, variando de 5 a 36 meses. Todas as lesöes foram detectadas pelo enema opaco e mimetizavam aspecto neoplásico. A colonoscopia foi realizada em três doentes, evidenciando lesöes sub-oclusivas da regiäo íleo-cecal em dois; as biópsias foram sugestivas de tuberculose, näo sendo possível diferenciá-las da doença de Crohn. RESULTADOS: Seis enfermos com diagnóstico presuntivo de neoplasia foram submetidos a cirurgia eletiva, realizando-se neles a colectomia direita clássica. Os outros dois, com suspeita de tuberculose, foram operados na vigência de obstruçäo intestinal, sendo submetidos a ressecçäo limitada (ileocecectomia). O estudo anatomopatológico estabeleceu o diagnóstico final pelo encontro de necrose caseosa e de bacilos álcool ácido-resistentes no intestino ou nos linfonodos. A evoluçäo pós-operatória foi satisfatória, com pequena morbidade resolvida clinicamente. Posteriormente, todos os doentes receberam o esquema tríplice por 12 meses, variando a droga de acordo com a época do tratamento. CONCLUSÄO: Apesar de rara, a tuberculose hipertrófica ileocecal isolada freqüentemente é confundida com neoplasias e com a doença de Crohn, devendo ser lembrada no diagnóstico diferencial das lesöes localizadas no quadrante inferior direito do abdome

Primary non-Hodgkin lymphoma of the right colon: a retrospective clinical-pathological study.

The objective of this study was to analyze the results of surgical treatment of primary non-Hodgkin lymphomas of the right colon. Ten patients were operated on with curative intention. Dawson's criteria were used to characterize the colonic lymphoma as a primary lymphomas. In the staging of the tumor, the Ann Arbor classification for gastrointestinal lymphomas modified by Musshoff and Schmidt-Vollmer was used. The histological classification was made by using the International Working Formulation Group system. All patients were submitted to radical right colectomy and 6 of them received postoperative chemotherapy. The overall average survival was 39.2 months. Four of the patients are still alive, without active disease, with an average survival of 85.2 months. Six patients died due to relapse in the abdomen, with an average survival of 8.2 months. These results suggest that it is advantageous to patient survival to have them submitted for resection of their lesions at an initial stage of the disease (IE and IIE1). Chemotherapy must be used as a complementary treatment in locally advanced lesions, in an attempt to control the residual microscopic disease.

The role of surgery in the treatment of primary gastric lymphoma.

The present retrospective study of 23 patients with primary gastric lymphoma had the objective of determining the role of surgical treatment on survival. All patients were submitted to gastric resection with regional lymph node removal. Nine patients (39.1%) received supplementary treatment (chemotherapy and/or radiotherapy). According to the Kiel classification, the most frequent histological type was the centroblastic (29.1%), and most patients (60.9%) had a low-grade lymphoma. According to the Ann Arbor classification, modified by Musshoff and Schmidt-Vollmer, stages were IE in 52.1%, II1E in 8.7%, II2E in 13.1%, and IV in 26.1% of the cases. Mean survival was 29.3 months. The variables that influenced survival rates were age, advanced stage tumor, and receiving postoperative adjuvant therapy. Analysis of our cases suggests that complete lesion resection along with adjacent lymph nodes, and supplementary postoperative treatment is the best approach for a resectable primary gastric lymphoma.

Gastric necrosis and perforation as a complication of splenectomy. Case report and related references.

Necrosis of the stomach after isolated splenectomy with the formation of gastrocutaneous fistula is a rare event that occurs in less than 1% of splenectomies. It is more frequent when the removal of the spleen is done because of hematological diseases. Its mortality index can reach 60% and its pathogenesis is controversial, as it may be attributed both to direct trauma of the gastric wall and to ischemic phenomena. Although the stomach may exhibit exuberant arterial blood irrigation, anatomical variations can cause a predisposition towards the appearance of potentially ischemic areas, especially after ligation of the short gastric vessels around the major curvature of the stomach. Once this is diagnosed in the immediate postoperative period, it becomes imperative to reoperate. The surgical procedure will depend on the conditions of the peritoneal cavity and patient's clinic status. The objective of this study was to report on the case of a patient submitted to splenectomy because of closed abdominal traumatism, who then presented peritonitis and percutaneous gastric fistula in the post-operative period. During the second operation, perforations were identified in anterior gastric wall where there had been signs of vascular stress. The lesion was sutured after revival of its borders, and the patient had good evolution. Prompt diagnosis and immediate treatment of this unusual complication are needed to reduce its high mortality rate.

Jejunal perforation caused by abdominal angiostrongyliasis.

The authors describe a case of abdominal angiostrongyliasis in an adult patient presenting acute abdominal pain caused by jejunal perforation. The case was unusual, as this affliction habitually involves the terminal ileum, appendix, cecum or ascending colon. The disease is caused by the nematode Angiostrongylus costaricensis, whose definitive hosts are forest rodents while snails and slugs are its intermediate hosts. Infection in humans is accidental and occurs via the ingestion of snail or slug mucoid secretions found on vegetables, or by direct contact with the mucus. Abdominal angiostrongyliasis is clinically characterized by prolonged fever, anorexia, abdominal pain in the right-lower quadrant, and peripheral blood eosinophilia. Although usually of a benign nature, its course may evolve to more complicated forms such as intestinal obstruction or perforation likely to require a surgical approach. Currently, no efficient medication for the treatment of abdominal angiostrongyliasis is known to be available. In this study, the authors provide a review on the subject, considering its etiopathogeny, clinical picture, diagnosis and treatment.

Surgical treatment for colorectal endometriosis.

The authors studied the surgical treatment of patients with intestinal endometriosis. A total of 10 patients, with a median age range of 43 years, underwent an operation. Cramp abdominal pain (100%), diarrhea (30%), constipation and enterorrhagia (20%) dominated the clinical picture. At the time of surgery, four patients presented intestinal obstructive symptoms. Five (50%) patients reported gynecological complaints. Four patients were infertile and five had prior surgical gynaecological events. Seven cases presented sigmoid involvement, and three had involvement of the cecal appendix. Pre-operative diagnosis was carried out in two patients only. Surgical indications were due to suspicion of cancer (4 patients), appendicitis (3 patients), diverticular disease (1 patient) and unmanageable pain (2 patients). The following procedures were performed: left colectomy (2 cases), rectosigmoidectomy (3 cases), sigmoidectomy (3 cases), colostomy (2 cases) and three appendicectomy cases associated with concomitant gynecological interventions. No postoperative complications or deaths were observed. The authors emphasize that intestinal stenotic lesions should be treated by means of extirpation while the parietal nodule should be treated by exeresis. Intestinal endometriosis should be suspected in cases of lower abdomen recurrent pain in premenopausal infertile women or with previous surgical, gynecological events associated with intestinal symptoms or distal colon stenosis.

Immobilized yeast bioreactor systems for continuous beer fermentation

Two different types of immobilized yeast bioreactors were examined for continuous fermentation of high-gravity worts. One of these is a fluidized bed reactor (FBR) that employs porous glass beads for yeast immobilization. The second system is a loop reactor containing a porous silicon carbide cartridge (SCCR) for immobilizing the yeast cells. Although there was some residual fermentable sugar in the SCCR system product, nearly complete attenuation of the wort sugars was achieved in either of the systems when operated as a two-stage process. Fermentation could be completed in these systems in only half the time required for a conventional batch process. Both the systems showed similar kinetics of extract consumption, and therefore similar volumetric productivity. As compared to the batch fermentation, total fusel alcohols were lower; total esters, while variable, were generally higher. The yeast biomass production was similar to that in a conventional fermentation process. As would be expected in an accelerated fermentation system, the levels of vicinal diketones (VDKs) were higher. To remove the VDKs, the young beer was heat-treated to convert the VDK precursors and processed through a packed bed immobilized yeast bioreactor for VDK assimilation. The finished product from the FBR system was found to be quite acceptable from a flavor perspective, albeit different from the product from a conventional batch process. Significantly shortened fermentation times demonstrate the feasibility of this technology for beer production.

Spontaneous perforations of the small intestine.

BACKGROUND AND METHODS: The present study describes the procedures used by the authors in the management of 34 patients with spontaneous perforation of the small intestine. RESULTS: Only one (2.9%) of the patients had the perforation cause diagnosed before laparotomy; 27 (80%) cases showed ileal perforative lesions while seven (20%) had jejunal lesions; 31 (91.1%) patients presented single perforations and three (8.8%) had multiple ones. Intestinal resection followed by anastomosis or ileostomy and colostomy, was carried out in 21 (61.7%) cases, and 13 (38.2%) patients were submitted to exeresis with edge restoration and lesion suture. The cause of perforation could be identified in 29 (86.3%) cases while in five (14.7%) patients the cause was considered idiopathic. Eighteen (53%) patients recovered from surgery and were discharged; there were 16 (47%) deaths resulting from a number of complications. CONCLUSIONS: Since the prognosis regarding this disease depends on the peritoneal infection severity level, the patient's organic resistance, and most of all, the time interval spent until the treatment is initiated, the authors emphasize the need to have a laparotomy performed as early as possible considering that this procedure provides the best chances of survival and health recovery.

Lipomas colorretais: correlaçäo anatomoclínica de 29 casos / Colorectal lipomas: anatomoclinical study of 29 cases

Objetivo. Avaliar a ocorrência de lipomas colorretais, métodos diagnósticos e conduta terapêutica, com o intuito de estabelecer normas no atendimento dos portadores desta afecçäo. Casuística e Métodos. Revisadas autópsias feitas em período de 6 anos e estudados os prontuários de portadores de lipomas colorretais tratados entre 1965 e 1993, com ênfase ao quadro clínico, conduta diagnóstica e terapêutica. Os 29 portadores de lipomas intestinais submucosos foram distribuídos em três grupos. O grupo I, cujos lipomas foram detetados em necrópsias; o grupo II, com doentes sintomáticos, e um terceiro grupo de enfermos assintomáticos, com lipomas encontrados acidentalmente em peças cirúrgicas ressecadas por neoplasias ou durante procedimentos diagnósticos. Resultados. 0,6 por cento dos autopsiados apresentaram lipomas colorretais, situados, preferencialmente, no cólon direito, predominando em mulheres (70,0 por cento). No grupo II, a enterorragia foi o sintoma mais freqüente (54,5 por cento), seguida pela dor abdominal em cólica e por alteraçöes do hábito intestinal. A intussuscepçäo ocorreu em três doentes (27,3 por cento). Ao contrário da literatura, os lipomas sintomáticos localizaram-se, preferencialmente, no cólon esquerdo, sendo seu tamanho médio de 6,1cm. Os diagnósticos foram realizados por meio do enema opaco e, mais recentemente, pela colofibroscopia e tomografia computadorizada. Neste grupo, foram realizadas ressecçöes em dez doentes, sendo cinco amplas, três locais e duas endoscópicas. Um paciente eliminou, espontaneamente, seu lipoma. Lipomas múltiplos foram detetados em 30 por cento dos autopsiados e em 25 por cento do grupo assintomático. Nestes dois grupos, nenhum dos tumores era maior que 2,0cm de diâmetro. Conclusöes. Lipomas colorretais säo raros, quer na clínica diária, quer em autópsias. Antes do advento da colofibroscopia e da tomografia, a maioria dos doentes era submetida a ressecçäo extensa, na suposiçäo de doença maligna. Posteriormente, a polipectomia endoscópica e a ressecçäo local passaram a ser nossa conduta preferencial.

[Colorectal lipomas: anatomoclinical study of 29 cases]. / Lipomas colorretais: correlação anatomoclínica de 29 casos.

OBJECT: To evaluate the incidence of colorectal lipomas, its diagnostic methodology and therapeutic management. CASUISTIC AND METHODS: The reviewed necropsies performed in a six years period and the patients' records from colorectal lipomas cases treated up to 1965 until 1993 were studied enhancing the clinical presentation, their diagnosis and therapy. The 29 cases of submucosal intestinal lipomas were disposed in three groups. The first group with ten patients lipomas were detected at necropsies. The second group with 11 symptomatic patients and group three with 8 asymptomatic patients which lipomas were discovered accidentally in surgical specimens resected due to neoplasm or in the course of diagnostical procedure. RESULTS: 0.56% of patients who were submitted to necropsy disclosed colorectal lipomas situated preferentially in right colon and in female. Enterourhage was the most often symptom (54.5%) in the group two, followed by cramp abdominal pain. Intussusception appeared in three patients (27.3%). Contrary to the medical literature, the symptomatic lipomas were preferentially situated in left colon and its mean size was 6.1 cm. The diagnosis were performed through opaque enema and more recently by colofibroscopy and CT scan. Resections were performed in all patients: five were enlarged, three were local and other three were endoscopic resections. Multiple lipomas were detected in 30% of patients who were submitted to necropsy and in 25% of asymptomatic group. In both groups no tumor was larger than 2.0 cm of diameter. CONCLUSIONS: Colorectal lipomas are rare in both clinical presentation and necropsy. Before the advent of CT scan and colofibroscopy the majority of the patients were submitted to wide resections, in the assumption of malignancy. Afterwards the endoscopic polipectomy and local resection became our preferential management.

Principles of protein folding--a perspective from simple exact models.

General principles of protein structure, stability, and folding kinetics have recently been explored in computer simulations of simple exact lattice models. These models represent protein chains at a rudimentary level, but they involve few parameters, approximations, or implicit biases, and they allow complete explorations of conformational and sequence spaces. Such simulations have resulted in testable predictions that are sometimes unanticipated: The folding code is mainly binary and delocalized throughout the amino acid sequence. The secondary and tertiary structures of a protein are specified mainly by the sequence of polar and nonpolar monomers. More specific interactions may refine the structure, rather than dominate the folding code. Simple exact models can account for the properties that characterize protein folding: two-state cooperativity, secondary and tertiary structures, and multistage folding kinetics--fast hydrophobic collapse followed by slower annealing. These studies suggest the possibility of creating "foldable" chain molecules other than proteins. The encoding of a unique compact chain conformation may not require amino acids; it may require only the ability to synthesize specific monomer sequences in which at least one monomer type is solvent-averse.

Models of cooperativity in protein folding.

What is the basis for the two-state cooperativity of protein folding? Since the 1950s, three main models have been put forward. 1. In 'helix-coil' theory, cooperativity is due to local interactions among near neighbours in the sequence. Helix-coil cooperativity is probably not the principal basis for the folding of globular proteins because it is not two-state, the forces are weak, it does not account for sheet proteins, and there is no evidence that helix formation precedes the formation of a hydrophobic core in the following pathways. 2. In the 'sidechain packing' model, cooperativity is attributed to the jigsaw-puzzle-like complementary fits of sidechains. This too is probably not the basis of folding cooperativity because exact models and experiments on homopolymers with sidechains give no evidence that sidechain freezing is two-state, sidechain complementarities in proteins are only weak trends, and the molten globule model predicted by this model is far more native-like than experiments indicate. 3. In the 'hydrophobic core collapse' model, cooperativity is due to the assembly of non-polar residues into a good core. Exact model studies show that this model gives two-state behaviour for some sequences of hydrophobic and polar monomers. It is based on strong forces. There is considerable experimental evidence for the kinetics this model predicts: the development of hydrophobic clusters and cores is concurrent with secondary structure formation. It predicts compact denatured states with sizes and degrees of disorder that are in reasonable agreement with experiments.

Ligation alters the pathway of urea-induced denaturation of the catalytic trimer of Escherichia coli aspartate transcarbamylase.

We have examined the pathway and energetics of urea-induced dissociation and unfolding of the catalytic trimer (c3) of aspartate transcarbamylase from Escherichia coli at low temperature in the absence and presence of carbamyl phosphate (CP; a substrate), N-(phosphonacetyl)-L-Asp (PALA; a bisubstrate analog), and 2 anionic inhibitors, Cl- and ATP, by analytical gel chromatography supplemented by activity assays and ultraviolet difference spectroscopy. In the absence of active-site ligands and in the presence of ATP, c3 dissociates below 2 M urea into swollen c chains that then gradually unfold from 2 to 6 M urea with little apparent cooperativity. Linear extrapolation to 0 M urea of free energies determined in 3 independent types of experiments yields estimates for delta Gdissociation at 7.5 degrees C of about 7-10 kcal m-1 per interface. delta Gunfolding of dissociated chains when modeled as a 2-state process is estimated to be very small, on the order of -2 kcal m-1. The data are also consistent with the possibility that the unfolding of the dissociated monomer is a 1-state swelling process. In the presence of the ligands CP and PALA, and in the presence of Cl-, c3 dissociates at much higher urea concentrations, and trimer dissociation and unfolding occur simultaneously and apparently cooperatively, at urea concentrations that increase with the affinity of the ligand.

Side-chain entropy and packing in proteins.

What role does side-chain packing play in protein stability and structure? To address this question, we compare a lattice model with side chains (SCM) to a linear lattice model without side chains (LCM). Self-avoiding configurations are enumerated in 2 and 3 dimensions exhaustively for short chains and by Monte Carlo sampling for chains up to 50 main-chain monomers long. This comparison shows that (1) side-chain degrees of freedom increase the entropy of open conformations, but side-chain steric exclusion decreases the entropy of compact conformations, thus producing a substantial entropy that opposes folding; (2) there is side-chain "freezing" or ordering, i.e., a sharp decrease in entropy, near maximum compactness; and (3) the different types of contacts among side chains (s) and main-chain elements (m) have different frequencies, and the frequencies have different dependencies on compactness. mm contacts contribute significantly only at high densities, suggesting that main-chain hydrogen bonding in proteins may be promoted by compactness. The distributions of mm, ms, and ss contacts in compact SCM configurations are similar to the distributions in protein structures in the Brookhaven Protein Data Bank. We propose that packing in proteins is more like the packing of nuts and bolts in a jar than like the pairwise matching of jigsaw puzzle pieces.