In situ Raman spectroscopy and synchrotron X-ray diffraction studies on maleic acid under high pressure conditions.

Maleic acid was studied by Raman spectroscopy and powder synchrotron X-ray diffraction (XRD) under high pressure conditions by using a diamond anvil cell. The Raman spectroscopy measurements were performed from ambient pressure up to 9.2 GPa in the 100-3200 cm-1 spectral range. While the XRD measurements were performed up to 10.1 GPa. Here we present the pressure-dependence behavior from both the Raman modes and cell parameters. Maleic acid lattice parameters decrease anisotropically as a function of pressure and a reduction of 27% in the volume of the unit cell was observed. Modifications in the material's compressibility were observed at around 2 and 6 GPa.

Antibacterial properties and modulation analysis of antibiotic activity of NaCe(MoO4)2 microcrystals.

This study reports the antibacterial properties and modulation analysis of antibiotic activity by NaCe(MoO4)2 microcrystals as well as their structural and morphological characterization. Evaluation of the antibacterial and antibiotic-modulating activity was carried out using the broth microdilution method. The Minimum Inhibitory Concentrations (MICs) of the compounds were expressed as the geometric mean of the triplicate values obtained through the use of Resazurin. Compound concentrations in the plates ranged from 512 to 0.5 µg/mL. Regarding its direct antibacterial activity, NaCe(MoO4)2 had a MIC ≥ 1024 µg/mL against all studied strains. As for its modulatory effect, it presented synergism with the antibiotic Gentamicin against the S. aureus strain and with Norfloxacin against E. coli, causing a reduction of 75% and 60%, respectively, in the antibiotic quantity required to have the same effect on the strain in study.

Modulation of antibiotic effect by Fe2(MoO4)3 microstrutures.

In this study, we report the antibacterial activity and modulation of antibiotic activity by Fe2(MoO4)3 microstructures obtained by the hydrothermal route without use of surfactants or organic additives. This material was characterized by X-ray diffraction (XRD), Raman spectroscopy and scanning electron microscopy (SEM) images. The XRD pattern showed that the Fe2(MoO4)3 crystallize in a monoclinic structure without secondary phases. Raman spectroscopy confirms the formation of Fe2(MoO4)3. SEM images show that the Fe2(MoO4)3 obtained have ball-of-yarn shaped morphology. In the antibacterial assays, strains of Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus were assayed by microdilution method to evaluate the antibacterial and modulatory-antibiotic activity with antibiotics as gentamicin, norfloxacin and imipenem. Against all bacteria, the Minimum Inhibitory Concentration (MIC) was Fe2(MoO4)3 ≥ 1024 µg/mL. This high MIC result must be associated with the fact of the iron be an essential microelement to the bacterial growth. However, when the Fe2(MoO4)3 was assayed in association with the antibiotics was observed an antagonistic effect demonstrated by an enhance of the MIC. This fact is associated directly with the pro-oxidative properties of metallic oxides. These compounds enhance the production of free radicals, as H2O2 and superoxide ions that can affect the cell structures as cell membrane and cell wall. Other effect is associated with the possible coordination of the metal, performing bonds with the chemical structure of the antibiotics, reducing their activity. Our results indicated that nanocompounds as Fe2(MoO4)3 can not be used as antimicrobial products for clinical usage, neither directly and neither in association with antibiotics.

Physicochemical analysis of Permian coprolites from Brazil.

In this paper we performed the study of two coprolites (fossilized feces) collected from the exposed levels of the Pedra de Fogo Formation, Parnaiba Sedimentary Basin, and Rio do Rasto Formation, Paraná Sedimentary Basin, both of the Palaeozoic era (Permian age). They were characterized using X-ray diffractometry, infrared, Raman and energy dispersive spectroscopy techniques in order to aid our understanding of the processes of fossilization and to discuss issues related to the feeding habits of the animals which generated those coprolites, probably cartilaginous fishes. The results obtained using a multitechnique approach showed that although these coprolites are from different geological formations, 3000km away from each other, they show the same major crystalline phases and elemental composition. The main phases found were hydroxyapatite, silica, calcite and hematite, which lead to infer that those coprolites were formed under similar conditions and produced by a similar group of carnivore or omnivore fishes.

ß-Ag2MoO4 microcrystals: Characterization, antibacterial properties and modulation analysis of antibiotic activity.

This study reports the antibacterial properties and modulation analysis of antibiotic activity by ß-Ag2MoO4 microcrystals as well as their structural and vibrational characterization. The silver molybdate was obtained by the conventional hydrothermal method, and the structural, vibrational and morphological properties of the sample were determined using X-ray diffraction, Raman spectroscopy and scanning electron microscopy images. ß-Ag2MoO4 microcrystals obtained show spinel-type cubic structure (Fd-3m) with irregular shapes. The evaluation of antibacterial and modulatory-antibiotic activity was performed using the microdilution method to determine the Minimum Inhibitory Concentration (MIC) of the ß-Ag2MoO4 and antibiotics alone and associated with the silver molybdate. The ß-Ag2MoO4 modulates the antibiotic activity against all bacteria assayed in a synergistic (as the norfloxacin and gentamicin against S. aureus and gentamicin against E. coli) or an antagonistic form (as the norfloxacin against E.coli and P. aeruginosa). The reversion of antibiotic resistance by combinations with Ag2MoO4 could be a novel strategy to combat infections caused by multiple drug resistance (MDR) pathogens. Our results indicate that these silver molybdates present a clinically relevant antibacterial activity and enhanced the antibiotic activity of some antibiotics against MDR strain of S. aureus and E. coli, being an interesting alternative to combat antibiotic-resistant bacterial infectious agents.

Spectroscopic studies of the fish fossils (Cladocyclus gardneri and Vinctifer comptoni) from the Ipubi Formation of the Cretaceous Period.

Fossils are mineralized remains or traces from animals, plants and other organisms aged to about 10(8)years. The chemical processes of fossilization are dated back from old geological periods on Earth. The understanding of these processes and the structure of the fossils are one of the goals of paleontology and geology in the sedimentary environments. Many researches have tried to unveil details about special kinds of biological samples; however, a lack of data is noticed for various other specimens. This study reports the investigations through infrared spectroscopy, X-ray fluorescence and X-ray diffraction measurements for two types of fish fossils from the Cretaceous Period. The sample of Cladocyclus gardneri and Vinctifer comptoni fossils were collected from the Ipubi Formation, being one of the less studied, among the formations that constitute the important Santana group in the Araripe Basin, Brazil. The results obtained through different techniques, showed that the C. gardneri fish fossil contains hydroxyapatite and calcite as constituents whereas its rock matrix was formed by calcite, quartz and pyrite. Regarding the V. comptoni, the measurements confirmed the presence of hydroxyapatite in the fossil and its rock matrix gypsum, pyrite, quartz and calcite. The above scientific data contributed to the understanding the fossil formation in the Ipubi Formation, an important environment of the Cretaceous Period, which is rich in well-preserved fossils from different species.

Temperature-dependent vibrational spectroscopic study and DFT calculations of the sorbic acid.

This work reports a temperature-dependent vibrational spectroscopic study of the sorbic acid (C6H8O2), as well as the mode assignment at ambient conditions, based on the density functional theory. Temperature-dependent vibrational properties have been performed in polycrystalline sorbic acid through both Raman and infrared spectroscopy in the 20-300 K and 80-300 K temperature ranges, respectively. These studies present the occurrence of some modifications in the Raman spectra that could be interpreted as a low temperature phase transition undergone by sorbic acid from the monoclinic phase to an unknown phase with conformational change of the molecules in the unit cell.

Spectroscopic studies of wood fossils from the Crato Formation, Cretaceous Period.

In this work we study two types of wood fossils (Gymnosperms, Araucariaceae) from the Crato Formation of Araripe Basin in Brazil, from the Cretaceous Period. The samples were characterized by Raman and infrared spectroscopies, X-ray diffraction and scanning electron microscopy. The results obtained by different techniques showed that although the rocks surrounding the fossils have predominantly the same constitution - calcite - however, the formation processes of these types of wood fossils are quite different. One of the fossils, denominated as light wood, is predominantly composed of gypsum, while the other fossil, the dark wood, is rich in amorphous carbon, possibly the kerogen type. Implications relative to the environment where the plants lived millions years ago are also given. Finally, the results highlight the constitution of one of the most important paleontological sites of the Cretaceous Period in the South America.

Pilonidal cyst: cause and treatment.

PURPOSE: The treatment of sacrococcygeal pilonidal cyst, despite being considered a well-defined clinical entity and opinion as to its acquired origin being almost unanimous, has some controversial aspects. Surgery is the principal method of treatment, and several techniques have been proposed. All of them try to reduce morbidity, to offer conditions of fast cicatrization, to have a low recurrence rate, and to offer cure. This study was undertaken to review the available data in the literature about the cause of the disease and to determine the current optimal method of treatment, evaluating morbidity, healing, recurrence, and cure. METHODS: Data available on the topic of pilonidal cyst in the English-language literature were obtained from Index Medicus and MEDLINE and were reviewed and analyzed. RESULTS: There is nearly a consensus that pilonidal cyst is acquired, hair being the agent that causes the disease. Presently, the most-used surgical procedure is excision of the cyst, with open or closed wound for healing. However, many authors prefer to use the method of incision and curettage. New surgical techniques are being proposed. CONCLUSION: The majority of authors conclude that sacrococcygeal pilonidal cyst is an acquired disease, although a minority believe it is congenital. Although excision is the method of choice for most surgeons, in our experience the incision and curettage procedure is the best surgical treatment with regard to morbidity, healing, recurrence, and cure of the disease.

Absorption of rectally administered phenytoin: a pilot study.

OBJECTIVE: To test the hypothesis that rectally administered phenytoin is absorbed in healthy volunteers. DESIGN: This single-center, open-label crossover pilot study compared rectal absorption with intravenous administration of phenytoin injectable solution (7 mg/kg) in healthy volunteers. Twelve serial blood samples were taken from each volunteer beginning at time zero until 36 hours following administration. These were analyzed for presence of phenytoin by immunoassay. SETTING: The study took place at St. Paul's Hospital, a tertiary care center. PARTICIPANTS: Funding permitted for a sample size of five healthy participants, two men and three women, aged 21-45 years. Selection was by volunteer sample. Inclusion criteria were as follows: no known medical conditions, not receiving medication, no history of adverse drug reactions or allergies, not known to be pregnant, and normal liver function as determined per study protocol. MAIN OUTCOME MEASURES: Signs of absorption as indicated by presence of phenytoin in blood samples, maximum concentrations (Cmax), time to Cmax (tmax), AUC, and apparent bioavailability. RESULTS: Maximum mean concentrations of 2.4+/-1.1 mg/L (mean +/- SD) following rectal administration and 11.2+/-1.6 mg/L following intravenous administration were achieved during the first one to two hours (tmax in both treatment arms). Mean apparent bioavailability of the rectally administered phenytoin was 24.4+/-13.4% (15.8-44.1%). CONCLUSIONS: Results from this pilot study demonstrate that rectal absorption of phenytoin begins within 30 minutes following single-dose administration and was reported by four out of five volunteers to be the preferred route. Further studies are required before extrapolation can be made to the patient population.

Pouchitis: extracolonic manifestation of ulcerative colitis?

Pouchitis is the most frequent complication of ileal pouch-anal anastomosis for treatment of ulcerative colitis. There are several possible explanations. Among them, we focus on the one that considers pouchitis as an extracolonic manifestation of ulcerative colitis. The aim of this study was to investigate the association between pouchitis and extra-intestinal manifestations (EIM), which are frequent in these patients. Sixty patients underwent restorative proctocolectomy with an ileal J pouch (IPAA) from September 1984 to December 1998. Pouchitis was defined by clinical, endoscopic, and histologic criteria. The following extra-intestinal manifestations were studied: articular, cutaneous, hepatobiliary, ocular, genitourinary, and growth failure. Thirteen patients, of which 10 were female (76.9%), developed one or more episodes of pouchitis. Twelve patients of this group (92.3%) presented some kind of extra-intestinal manifestation, 4 pre-operatively (exclusively), 2 post-operatively (exclusively), and 6 both pre- and post-operatively (1.7 per patient). Twenty patients (42.7%) of the 47 without pouchitis did not present extra-intestinal manifestations; 10/35 (28. 5%) of females had pouchitis, compared to 3/35 (12.0%) of men. Pouchitis was more frequent among females, though not statistically significant. EIM increases the risk of pouchitis. Pouchitis is related to EIM in 92.3 % of cases, corroborating the hypothesis that it could be an extracolonic manifestation of ulcerative colitis.

[Ambulatory anorectal surgery under local anesthesia: analysis of 351 procedures]. / Cirurgia proctológica ambulatorial sob anestesia local: análise de 351 operações.

Three hundred and twenty-eight patients with anorectal diseases were submitted ambulatory surgery, under local anesthesia, in a three-year period. Three hundred and fifty one operations were performed in outpatient service. Local anesthesia by Hook-Needle Puncture technique was used in 37 operations and the rest of them by classical technique through infiltration of both lateral anal quadrants. Hemorrhoids, fistulas, fissures and pilonidal cysts were the most frequent diseases treated (71.6%). The incidence of early and late complications was 19.6% and 4.8%, respectively. The most common complication was severe pain (16.1%). Five patients (1.5%) required hospitalization due postoperative complications. The surgery on an outpatient basis was a well-accepted procedure for two hundred eighty-eight patients (88%). The main benefit reported by patients was the possibility of recovery at home, which is more comfortable. The ambulatory anorectal surgery under local anesthesia is a safe and effective method, with the additional advantage of the costs saved and increase of available beds for more complex surgery.

[Primary lymphomas of the large intestine]. / Linfomas primários do intestino grosso.

Primary colorectal lymphomas are rare tumors that comprise 0.5 to 2% of large bowel malignancies and 10 to 20% of gastrointestinal lymphomas. Between 1982-1993 ten patients were treated in the Colorectal Unit of the "Hospital das Clínicas" of the University of São Paulo, representing 2% of the neoplasms in this period. Age varied from 22 to 76 years, with median around 50 years, and male/female ratio 8:2. Weight loss, right iliac palpable mass and bowel habit alterations were the most common symptoms. Definitive diagnostic was only set with histological evaluation of the surgical specimen in all colon tumors. Four patients had advanced disease classified as stages III or IV. The tumors were located in ileocecal region (7 cases), transverse colon (1 case), sigmoid colon (1 case) and rectum (1 case). Colon lymphomas were treated by radical surgical resection and chemotherapy; the patient with rectal lymphoma received radiotherapy and chemotherapy because of local tumor spread. Histological data showed 6 large cell lymphomas and 4 small cleaved cells lymphomas. Lymphnodal involvement and tumor size were the main prognostic factors in the series: 80% of the patients in advanced stage (III or IV) and 66% of those with tumors larger than 10 cm died during the first year of the follow-up.

Restaging of colorectal cancer based on the identification of lymph node micrometastases through immunoperoxidase staining of CEA and cytokeratins.

The present study was performed to identify tumor cells in lymph nodes from colorectal adenocarcinomas considered free of disease by the classic hematoxylin-eosin stain, based on the detection of the carcinoembryonic antigen (CEA) and cytokeratins in neoplastic epithelial cells. For this purpose, 603 lymph nodes from 46 lesions were stained by the peroxidase-antiperoxidase technique. Tumor cells were detected in 22 nodes from 12 patients, mainly in the subcapsular sinuses, permitting a restaging of these patients into two groups: those now considered to have metastatic disease and those free of metastases. However, the 5-year follow-up showed no statistical differences in survival between the two groups.

[Malacoplakia of the large intestine, bladder and retroperitoneum: a case report]. / Malacoplasia do intestino grosso, bexiga e retroperitônio: relato de um caso.

The authors present a case of malakoplakia, involving colon, rectum, bladder and retroperitoneum. This rare pathology, generally associated to Escherichia coli infections, result in a granulomatous disease, that can involve one or more organs. Nowadays, it is believed that the illness is due to a failure in the bactericide activity of the macrophage. This case, the first reported in our country, was treated clinically with ascorbic acid and trimethoprim-sulfamethoxazole, and is also unique in the world literature.

Epidermoid carcinoma of the anal canal. Results of treatment by combined chemotherapy and radiation therapy.

Thirty consecutive patients with epidermoid carcinomas of the anal canal larger than 2 cm were treated with the concomitant application of radiation and two cycles of chemotherapy (5FU and mitomycin-C) between January 1982 and January 1988. Twenty-eight patients were treated with curative intention and two for palliation only. All patients were reexamined after a period of one to 2 months, under light general anesthesia, and any residual tumor or scar tissue was biopsied. Control biopsy was positive in eight patients. Three of six patients who had abdominoperineal excision died from locoregional recurrence; the remaining are alive and cancer free after 1 to 4 years. Two patients had local excision; one is alive and the other died of other cancer metastasis four years later. Seventeen patients who had negative biopsies are alive and free of disease after 1 to 5 years; two died of unrelated causes, two died with distant metastasis (present prior to treatment), and one died with locoregional recurrence. Locoregional failures occurred in four patients (13.3 percent) in the entire series. Individualization of each patient, adjustment of doses, and carefully executed radiation and chemotherapy are the most important points for the success of treatment.

Stapled anastomosis in colorectal surgery.

The authors review their experience with stapled anastomosis in colorectal and ileorectal resections for malignant and benign lesions of the large bowel. They describe the technique and results in a series of 49 patients (24 with cancer of the rectum and rectosigmoid junction; six with familial polyposis, associated with cancer in four; 12 with chagastic megacolon; three, Crohn's disease; two, ulcerative colitis; and one each, diverticular sigmoiditis and ischemic sigmoiditis). Anterior resection was performed in 38 patients and total colectomy with ileorectal anastomosis in 11. Main complications and mortality are presented. They conclude that stapled anastomosis is an efficient method for intestinal reconstruction after resection for malignant and benign lesions of the large bowel.

[Nodular lymphoid hyperplasia of the duodenum: study of 3 cases]. / Hiperplasia linfóide nodular do duodeno: estudo de 3 casos

We have studied three cases of patients with lymphoid nodular duodenal hyperplasia, two of them being in the child group. We observed giardiasis in one of the cases of this child group. Also vague dyspeptical complaints in all cases were noticed. The diagnostics were based on the results obtained with endoscopy, later confirmed by hystological tests. We found two cases with absence of IgA without alterations in IgG and IgM when using immunoeletrophoresis.