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1.
BACKGROUND: Nitric oxide (NO) plays a key role in wound repair and S-nitrosothiols like S-nitrosoglutathione (GSNO) are well known NO donors. METHODS: Animals were separated in two groups and submitted to excisional wounds on the dorsal surface at the first day. GSNO (100 microm)-containing hydrogels were topically applied on the wound bed in the GSNO group, daily, during the first 4 days. Control group was topically treated with hydrogel without GSNO for the same period. Wound contraction and re-epithelialization were measured. Animals were sacrificed 21 days after wounding. Samples of lesion and normal tissue were formalin-fixed, paraffin embedded for histological analysis. RESULTS: Wound contraction, measured 14 and 21 days after wounding, was greater in the GSNO group than in the control group (P<0.05 for both). The re-epithelialized wound area, measured 14 days after wounding, was higher in the GSNO group than in the control group (P<0.05). A higher amount of inflammatory cells was observed in superficial and deep areas of the granulation tissue of the control group compared to the GSNO group. Twenty-one days after wounding, thin red-yellow collagen fibers arranged perpendicularly to the surface were found in the granulation tissue of the control group, whereas in the GSNO-treated group collagen fibers were thicker and arranged parallel to the surface. Increased number of mast cells was observed in the GSNO group compared with that in the control group. Vascularization and myofibroblast distribution were similar in both groups. CONCLUSION: Topical application of GSNO-containing hydrogel during the early phases of rat cutaneous wound repair accelerates wound closure and re-epithelialization and affects granulation tissue organization.  相似文献   
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Patients with chronic constipation fulfilling the Thompson criteria can show paradoxical sphincter contraction. Aim of this study was to evaluate rectal sensorimotor characteristics in patients with constipation with or without paradoxical sphincter contraction. Thirty female patients with chronic constipation and 22 female controls were investigated with anal manometry and rectal barostat. Paradoxical sphincter contraction was shown with manometry as a paradoxical increase of anal pressure during straining. Visceral sensitivity and compliance were tested by intermittent and continuous pressure-controlled distension. Patients were classified according to their sensations and compliance into normal, hypersensitive, reduced compliant, insensitive or excessive compliant rectum. Postprandial rectal response (PRR) and phasic volume events (PVEs) were registered for 1 h after a 600-kCal meal. Paradoxical sphincter contraction was found in 13 (43%) patients. In these patients, rectal sensitivity scores were higher (P = 0.045) than in patients without paradoxical contractions, but rectal compliance was not different. In 90% of patients an abnormal rectal sensitivity or compliance was found: excessively compliant in 35%, reduced compliant in 10%, hypersensitive in 27% and hyposensitive in 17%. Both patients with constipation (11%; P = 0.042) and controls (25%; P = 0.002) exhibited the presence of a postprandial rectal response. This response was not significantly different between idiopathic constipation, paradoxical sphincter contraction and controls. Patients with rectal hypersensitivity had lower response than other patients (P = 0.04). Patients with constipation had fewer basal PVEs compared controls (P = 0.03). Postprandial PVEs increased in both patients (P = 0.014) and controls (P < 0.001). Postprandial rectal response and PVE were not different in patients with or without paradoxical sphincter contraction. A total of 90% of female patients with idiopathic constipation show an abnormality in rectal sensation or compliance. The postprandial rectal response was comparable between patients with constipation and controls, however, PVEs were diminished. Patients with paradoxical sphincter contraction had higher rectal sensitivity but an unaltered compliance and postprandial rectal response. Future trials should investigate whether the classification of rectal abnormalities in patients with constipation has clinical importance.  相似文献   
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BACKGROUND: Herpesviruses are a significant cause of human morbidity. Traditional approaches to the identification of these viruses require infectious or at least antigenic virus. Multiplex PCR (mPCR) is capable of simultaneously amplifying a range of targets from a single preparation of nucleic acids and when combined with a suitable detection assay, it is capable of discriminating each of the amplicons. OBJECTIVES: Several methods have been described in the literature, however, they lack one or more significant design features required to suitably control a routinely applied nucleic acid amplification assay. We aimed to design a multiplex herpesvirus PCR that could co-amplify eight human herpesvirus targets plus an internal control (IC) molecule in a single tube. STUDY DESIGN: Primers were designed to target the DNA polymerase genes of each of the human herpesviruses. Synthetic controls were developed to act as templates for the evaluation of assay sensitivity and specificity and for development of an in-house competitive quantitative PCR. Amplicon was discriminated using a simplified enzyme linked amplicon hybridisation assay (ELAHA). RESULTS AND CONCLUSIONS: For routine diagnostic use we reduced the number of herpesviral targets from 8 to 6 in order to maintain adequate clinical sensitivity. The ELAHA proved more sensitive than agarose gel electrophoresis. Additionally, 36 cytomegalovirus positive patients were examined with an in-house quantitative PCR-ELAHA which was developed to confirm that that the mPCR's co-detection limit of 10(2) copy of synthetic template per millilitre was relevant for use in detecting virus from clinical samples. The mPCR-ELAHA was then applied to the screening of 174 patient specimens resulting in a specificity of 98% and a sensitivity of 93%. This preliminary study demonstrated that the mPCR-ELAHA was a complete approach to the detection of herpesviruses from a range of clinical samples and disease states.  相似文献   
4.
BACKGROUND: Boys and young men with hemophilia treated with factor infusions before 1985 had a substantial risk of acquiring the human immunodeficiency virus (HIV) and the acquired immunodeficiency syndrome. This study was designed to assess the effects of HIV and hemophilia per se on neurological function in a large cohort of subjects with hemophilia, and to investigate the relationships between neurological disease and death during follow-up. METHODS: Three hundred thirty-three boys and young men (207 HIV seropositive and 126 HIV seronegative) were evaluated longitudinally in a multicenter, multidisciplinary study. Neurological history and examination were conducted at baseline and annually for 4 years. The relationship between neurological variables, HIV serostatus, CD4+ cell counts, and vital status at the conclusion of the study was examined using logistic regression models. RESULTS: The risks of nonhemophilia-associated muscle atrophy, behavior change, and gait disturbance increased with time in immune compromised HIV-seropositive subjects compared with HIV seronegative or immunologically stable HIV-seropositive subjects. The risk of behavior change in immune compromised HIV-seropositive hemophiliacs, for example, rose to 60% by year 4 versus 10% to 17% for the other study groups. Forty-five subjects (13.5%), all of whom were HIV seropositive, died by year 4. Subjects who died had had increased risks of hyperreflexia, nonhemophilia-associated muscle atrophy, and behavior change. CONCLUSIONS: These results indicate that immune compromised, HIV-seropositive hemophiliacs have high rates of neurological abnormalities over time and that neurological abnormalities were common among subjects who later died. By contrast, immunologically stable HIV-seropositive subjects did not differ from the HIV-seronegative participants. Hemophilia per se was associated with progressive abnormalities of gait, coordination, and motor function.  相似文献   
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SUMMARY This double-blind, randomised, cross-over study investigated the antihypertensive efficacy of ramipril and enalapril was completed by 30 patients with mild-to-moderate essential hypertension. After a four-week placebo run-in phase, the patients received either 2.5mg ramipril or 10mg enalapril once daily for four weeks. The dosages were increased to 5mg ramipril and 20mg enalapril for a further four weeks. After a placebo washout phase of four weeks, the patients were crossed over to the alternative treatment. The decrease in average 24-hour ambulatory diastolic blood pressure from week 0 to week 8 was 1.6mmHg greater with ramipril than enalapril (90% confidence interval 0.6-2.7mmHg). The corresponding reduction in for systolic blood pressure was also greater with ramipril than enalapril by 2.4mmHg (90% confidence interval: 0.5-4.2mmHg). For the difference in the drop of 24-hour ambulatory diastolic blood pressure between ramipril and enalapril the lower level of the 90% confidence interval (CI) is above the clinically relevant difference of -3mmHg. This is an indication that ramipril (2.5 and 5mg dose) is at least as effective as enalapril (10 and 20mg dose) in decreasing blood pressure in patients with mild-to-moderate essential hypertension. The duration of adequate antihypertensive effect was relatively long for both ramipril and enalapril; however, ramipril tended to have a more prolonged antihypertensive effect. Ramipril had a higher diastolic and systolic trough/peak ratio than enalapril, resulting in a more uniform antihypertensive effect over the 24-hour treatment period. Both ramipril and enalapril were well tolerated and the two treatment groups had similar safety profiles.  相似文献   
9.
Real-time PCR assays for detection of bocavirus in human specimens   总被引:10,自引:0,他引:10       下载免费PDF全文
The recently discovered human bocavirus (HBoV) is the first member of the family Parvoviridae, genus Bocavirus, to be potentially associated with human disease. Several studies have identified HBoV in respiratory specimens from children with acute respiratory disease, but the full spectrum of clinical disease and the epidemiology of HBoV infection remain unclear. The availability of rapid and reliable molecular diagnostics would therefore aid future studies of this novel virus. To address this, we developed two sensitive and specific real-time TaqMan PCR assays that target the HBoV NS1 and NP-1 genes. Both assays could reproducibly detect 10 copies of a recombinant DNA plasmid containing a partial region of the HBoV genome, with a dynamic range of 8 log units (10(1) to 10(8) copies). Eight blinded clinical specimen extracts positive for HBoV by an independent PCR assay were positive by both real-time assays. Among 1,178 NP swabs collected from hospitalized pneumonia patients in Sa Kaeo Province, Thailand, 53 (4.5%) were reproducibly positive for HBoV by one or both targets. Our data confirm the possible association of HBoV infection with pneumonia and demonstrate the utility of these real-time PCR assays for HBoV detection.  相似文献   
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