946 resultados para Gram-positive and Gram-negative microorganisms


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Here we present a possible way to relate the method of covariantizing the gauge-dependent pole and the negative dimensional integration method for computing Feynman integrals pertinent to the light-cone gauge fields. Both techniques are applicable to the algebraic light-cone gauge and dispense with prescriptions to treat the characteristic poles.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Marfan syndrome (MFS) is an autosomal dominant trait due to mutations in the fibrillin gene (FBN1). The MFS expressivity is variable, and its diagnosis relies completely on clinical criteria. Atypical cases and Marfan- like (marfanoid) clinical presentations are commonly found. The metacarpophalangeal pattern profile (MCPP), a radiological method in which the 19 tubular hand bones are assessed, has been used in the diagnosis of various syndromes. To investigate whether the MCPP was adequate to discriminate between MFS and Marfan-like subjects, we studied 38 patients who were referred to our service because they had an MFS diagnosis, diagnostic hypothesis, or differential diagnosis or had arachnodactyly with dolichostenomelia. Two groups were formed: 1) MFS: 21 patients with a mean age of 18.3 (10.8 S.D.) years and 2) Marfan-like syndromes: 16 patients who did not meet the current criteria, with a mean age of 14.6 (4.6 S.D.) years. The MCPP was performed in each case following the classical technique, and a characteristic mean profile was obtained for group I (MFS), with Z scores ranging from 0.69 to 2.73 (1.80 ± 0.50; mean ± S.D.). In group I, three cases had no correlation with the typical MFS pattern. In group II, three cases had an MFS pattern. The correlation with the mean MCPP of MFS permitted the differential diagnosis of MFS and marfanoid syndromes with 86% sensitivity, 81% specificity, and 86% positive and 81% negative predictive values. The results suggest that MCPP can be used effectively as an auxiliary tool in the nosology of these conditions and, because there is no change in MCPP with age, can be helpful in early diagnosis.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The problem of existence and uniqueness of polynomial solutions of the Lamé differential equation A(x)y″ + 2B(x)y′ + C(x)y = 0, where A(x),B(x) and C(x) are polynomials of degree p + 1,p and p - 1, is under discussion. We concentrate on the case when A(x) has only real zeros aj and, in contrast to a classical result of Heine and Stieltjes which concerns the case of positive coefficients rj in the partial fraction decomposition B(x)/A(x) = ∑j p=0 rj/(x - aj), we allow the presence of both positive and negative coefficients rj. The corresponding electrostatic interpretation of the zeros of the solution y(x) as points of equilibrium in an electrostatic field generated by charges rj at aj is given. As an application we prove that the zeros of the Gegenbauer-Laurent polynomials are the points of unique equilibrium in a field generated by two positive and two negative charges. © 2000 American Mathematical Society.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Kaposi's sarcoma (KS) became a critical health issue with the emergence of acquired immunodeficiency syndrome (AIDS) in the 1980s. Four clinical-epidemiological forms of KS have been described: classical KS, endemic KS,iatrogenic KS, and AIDS-associated KS. In 1994, Kaposi's sarcoma-associated herpesvirus (KSHV) or human herpesvirus type 8 was identified by Chang and colleagues, and has been detected worldwide at frequencies ranging from 80 to 100%. The aim of the present study was to evaluate the frequency of KSHV infection in KS lesions from HIV-positive and HIV-negative patients in Brazil, as well as to review the current knowledge about KS transmission and detection. For these purposes, DNA from 51 cases of KS was assessed by PCR: 20 (39.2%) cases of classical KS, 29 (56.9%) of AIDS-associated KS and 2 (3.9%) of iatrogenic KS. Most patients were males (7.5:1, M/F), and mean age was 47.9 years (SD = ± 18.7 years). As expected, HIV-positive KS patients were younger than patients with classical KS. On the other hand, patients with AIDS-associated KS have early lesions (patch and plaque) compared to classical KS patients (predominantly nodular lesions). This is assumed to be the result of the early diagnose of KS in the HIV-positive setting. KSHV infection was detected by PCR in almost all cases (48/51; 94.1%), irrespectively of the clinical-epidemiological form of KS. These results show that KSHV is associated with all forms of KS in Brazilian patients, a fact that supports the role of this virus in KS pathogenesis. © 2006 Brazilian Journal of Medical and Biological Research.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The presence of Staphylococcus aureus in the nasal cavities and pericatheter skin of peritoneal dialysis patients put them at high risk of developing peritonitis. However, it is not clear whether the presence of coagulase-negative staphylococci (CNS) in the nasal passages and skin of patients is related to subsequent occurrence of peritoneal infection. The aim of the present study was to verify the relationship between endogenous sources of S. aureus and CNS and occurrence of peritonitis in patients undergoing peritoneal dialysis. Thirty-two patients on peritoneal hemodialysis were observed for 18 months. Staphylococcus species present in their nasal passage, pericatheter skin and peritoneal effluent were identified and compared based on drug susceptibility tests and dendrograms, which were drawn to better visualize the similarity among strains from extraperitoneal sites as well as their involvement in the causes of infection. Out of 288 Staphylococcus strains isolated, 155 (53.8%) were detected in the nasal cavity, 122 (42.4%) on the skin, and 11 (3.8%) in the peritoneal effluent of patients who developed peritonitis during the study. The most frequent Staphylococcus species were CNS (78.1%), compared with S. aureus (21.9%). Among CNS, S. epidermidis was predominant (64.4%), followed by S. warneri (15.1%), S. haemolyticus (10.7%), and other species (9.8%). Seven (64%) out of 11 cases of peritonitis analyzed presented similar strains. The same strain was isolated from different sites in two (66%) out of three S. aureus infection cases. In the six cases of S. epidermidis peritonitis, the species that caused infection was also found in the normal flora. From these, two cases (33%) presented highly similar strains and in three cases (50%), it was difficult to group strains as to similarity. Patients colonized with multidrug-resistant S. epidermidis strains were more predisposed to infection. Results demonstrated that an endogenous source of S. epidermidis could cause peritonitis in peritoneal dialysis patients, similarly to what has been observed with S. aureus.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Objective : The aim of the present study was to evaluate the antimicrobial activity of endodontic sealers against microorganisms. Materials and Methods : The agar diffusion method was used. A double base layer of Mueller Hinton agar was done. The microorganisms used were: Candida albicans, Enterococcus faecalis, Escherichia coli and Staphylococcus aureus. The wells were obtained by removing a standardized portion of the agar. After the distribution of the sealers, Petri plates were incubated for 24 h. Inhibition halos formed around the wells were measured. Results : Epiphany did not show any antimicrobial activity on the tested microorganisms (without inhibition halo). The AH Plus showed the greatest inhibition halo on C. albicans followed by EndoREZ on S. aureus. EndoREZ also showed greater inhibition halo in comparison to AH Plus on E. faecalis and E. coli. Conclusion : It could be concluded that AH Plus and EndoREZ showed antimicrobial activity against all the tested microorganisms. No antimicrobial activity was observed for Epiphany.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Chiroptera, the second largest mammalian order, presents different reproductive strategies and unique reproductive features. However, there are few reports regarding male reproductive accessory glands (RAGs) in Chiroptera. Thus, the aim of the present study was to characterise the RAGs of the exclusively neotropical bat Artibeus planirostris (Chiroptera: Phyllostomidae) macroscopically, microscopically and ultrastructurally. The RAGs were composed of a prostatic complex with two regions (ventral and dorsal) and paraurethral and bulbourethral glands, but no seminal vesicles. The ventral region had an undefined epithelium, with secretory and basal cells, and its secretions were periodic acid-Schiff (PAS) positive. The dorsal region received both deferens ducts, had a columnar pseudostratified epithelium with secretory and basal cells. There were two types of secretions from the dorsal region: one that was basophilic and another that was mixed PAS positive and PAS negative. The paraurethral glands were dispersed in the connective tissue of the urethra, whereas the bulbourethral glands were located in the penile root. Histological and ultrastructural data confirmed the prostatic nature of the ventral and dorsal regions and the holocrine nature of the ventral region, with the latter finding never having been described previously for the prostate gland. Our findings demonstrate the wide discrepancy of RAGs between A. planirostris and other mammals in terms of their composition, structure and morphology. © CSIRO 2013.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The purpose of this study was to evaluate the effectiveness of glycolic propolis (PRO) and ginger (GIN) extracts, calcium hydroxide (CH), chlorhexidine (CLX) gel and their combinations as ICMs (ICMs) against Candida albicans, Enterococcus faecalis, Escherichia coli and endotoxins in root canals. Material and Methods: After 28 days of contamination with microorganisms, the canals were instrumented and then divided according to the ICM: CH+saline; CLX, CH+CLX, PRO, PRO+CH; GIN; GIN+CH; saline. The antimicrobial activity and quantification of endotoxins by the chromogenic test of Limulus amebocyte lysate were evaluated after contamination and instrumentation at 14 days of ICM application and 7 days after ICM removal. Results and Conclusion: After analysis of results and application ofthe Kruskal-Wallis and Dunn statistical tests at 5% significance level, it was concluded that all ICMs were able to eliminate the microorganisms in the root canals and reduce their amount of endotoxins; however, CH was more effective in neutralizing endotoxins and less effective against C. albicans and E. faecalis, requiring the use of medication combinations to obtain higher success.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The objective of this study was to evaluate the microbial susceptibility to ß-lactams and metronidazole, and evaluate the production of ß-lactamases by microorganisms isolated from patients with chronic or aggressive periodontitis. The samples were obtained from 50 patients with periodontitis and microorganisms were isolated onto selective and nonselective culture media, identified by biochemical methods and tested for susceptibility to antimicrobial agents (amoxicillin, amoxicillin/clavulanate, cefoxitin, imipenem, metronidazole, penicillin G). The isolates were resistant to at least 1 mg/ml of any drug tested were evaluated to verify the production of ß-lactamases by the method of double layer (or biological) and chromogenic cephalosporin using nitrocefin. The results evidenced resistance to amoxicillin and penicillin G, while the susceptibility to association amoxicillin/clavulanate, imipenem and cefoxitin was widely disseminated among the organisms. Resistance to these drugs showed a clear correlation with the production of ß-lactamase in the majority of microbial groups.