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The bactericidal action of three formulations of a povidone-iodine (PVI) complex in vitro, in vivo, and in the presence of competing organic matter was evaluated. Bacterial organisms included Staphylococcus aureus ATCC 25923 and 25 clinical isolates of Staph. aureus, designated KU 1-25. For the in vitro studies, 1.0 mL of bacterial inoculum containing 10(7) organisms was introduced into 9.0 mL of chemically stable 10% and 1% PVI formulations in sterile culture tubes, and 1.0-mL samples were withdrawn at set intervals. Samples were plated by using standard techniques and incubated for 24 hours, after which colony-forming units were counted. For in vivo studies, 0.1 mL of 10(6) Staph. aureus ATCC 25923 or KU inoculum was deposited on the dorsum of the hand of healthy human subjects. This area was wiped with a cotton swab saturated with 1%, 2.5%, or 10% PVI formulations. Samples were taken at 15 and 30 seconds after application of the iodophor. To test the bactericidal activity of the three formulations in the presence of a competing substrate, a swab soaked with sterile sheep's blood was applied to the skin and allowed to dry. The percentage of 10(4) Staph. aureus inoculum recovered allowed for comparison of the three products. In vitro, the 1% PVI formulation was bactericidal for 10(7) Staph. aureus within two minutes, as compared with the four minutes required by 10% PVI. On the skin contaminated with 10(6) organisms, the rates of killing within 30 seconds were comparable for both solutions.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
BACKGROUND: Patients with varicose veins seek medical assistance for many reasons, including esthetic ones. The development of suitable and more flexible instruments, along with less invasive techniques, enables the establishment of new therapeutic procedures. OBJECTIVE: To compare endovenous great saphenous vein photocoagulation with an 810 nm diode laser and the conventional stripping operation in the same patient. METHODS: Twenty patients selected for operative treatment of primary great saphenous vein insufficiency on duplex scanning were assigned to a bilateral random comparison. In all cases, both techniques were performed, one on each lower limb. Clinically, evaluation was assessed on the seventh, thirtieth, and sixtieth postoperative days. Patients underwent examination with duplex ultrasonography and air plethysmography during the follow-up. RESULTS: Patients who received endovenous photocoagulation presented with the same pain but fewer swellings and less bruising than the stripping side. Most patients indicated that the limb operated on by laser received more benefits than the other. There was only one recanalization and no adverse effects. The venous filling time showed better hemodynamics in both techniques. CONCLUSION: The endovenous great saphenous vein photocoagulation is safe and well tolerated and presents results comparable to those of conventional stripping.  相似文献   
4.
Familial amyloid polyneuropathy (FAP) is characterized by deposition of mutated transthyretin (TTR) in the peripheral nervous system. Prior to amyloid fibrils, nonfibrillar TTR aggregates are deposited inducing oxidative stress with increased nitration (3-NT). As the major source of TTR is the liver, liver transplantation (LT) is used to halt FAP. Given the shortage of liver donors, domino LT (DLT) using FAP livers is performed. The correlation between TTR deposition in the skin and nerve was tested in biopsies from normal individuals, asymptomatic carriers (FAP 0) and FAP patients; in FAP 0, nonfibrillar TTR was observed both in the skin and nerve in the same individuals; in patients, amyloid was detected in both tissues. The occurrence of amyloidosis in recipients of FAP livers was evaluated 1-7 years after DLT: TTR deposition occurred in the skin 3 years after transplantation either as amyloid or aggregates; in one of the recipients, fibrillar TTR was present in the epineurium 6 years after DLT. Deposits were scarce and 3-NT immunostaining was irrelevant. Nerve biopsies from DLT recipients had no FAP-related neuropathy. Our findings suggest that TTR amyloid formation occurs faster than predicted and that TTR of liver origin can cross the blood-nerve barrier. Recipients of FAP livers should be under surveillance for TTR deposition and tissue damage.  相似文献   
5.
A clinical isolate of Staphylococcus aureus interpreted as resistant to penicillin by the Autobac 1 susceptibility testing method (i.e., light-scattering index of 0.77) was found to be susceptible to penicillin by both the disk diffusion and broth dilution techniques. The growth rate of the clinical isolate during a 4-h incubation interval was similar to that of a known sensitive reference strain (S. aureus ATCC 25923) used as a control organism for the Autobac test. The bactericidal effect of penicillin was evaluated by measuring the rate of killing over a 4-h interval. The percentages of organisms surviving exposure to 5.0 or 2.5 U of penicillin G per ml (number of organisms recovered at 3 h/number of organisms introduced as inoculum) were 68 and 76%, respectively, for the clinical isolate and 15 and 21%, respectively, for the reference strain. After 24 h of incubation, penicillin was bactericidal for both strains. The need to increase the time of incubation for those S. aureus isolates resistant to penicillin after 3 h of standard incubation time in the Autobac system is discussed.  相似文献   
6.
Injuries to the central nervous system (CNS) trigger an inflammatory reaction with potentially devastating consequences. In this report we compared the characteristics of the inflammatory response on spinal cord injury (SCI) caused by a stab wound between the T7 and T9 vertebrae and spontaneous experimental autoimmune encephalomyelitis (EAE). SCI and EAE were compared in two types of myelin basic protein Ac1-11-specific T-cell receptor transgenic mice: T/R+ mice harbor regulatory T cells, and T/R- mice lack regulatory T cells. Our results show that 8 days after SCI, T/R- mice developed a strong T-cell infiltrate in the spinal cord, with remarkable down-modulation of CD4 expression that was accompanied by a local increase in Mac-3+ and F4/80+ reactivity and diffuse local and distal astrogliosis. In contrast, T/R+ mice exhibited a modest increase in CD4+ cells localized to the site of injury, without CD4 down-modulation; focal astrogliosis was restricted to the site of the lesion, although Mac-3+ and F4/80+ cells were also present. Similarly to T/R- mice that underwent SCI, T cells displaying down-modulated CD4 expression were found in the CNS of older T/R- mice afflicted by spontaneous EAE. Overall, our results suggest that common mechanisms regulate T-cell accumulation in CNS lesions of different causes, such as mechanic lesion or autoimmune-mediated damage.  相似文献   
7.
We investigated the effects of oral L-glutamine (Gln) supplementation, associated or not with physical exercises, in control of glycemia, oxidative stress, and strength/power of knee muscles in elderly women. Physically active (n = 21) and sedentary (n = 23) elderly women aged 60 to 80 years were enrolled in the study. Plasma levels of D-fructosamine, insulin, reduced (GSH) and oxidized (GSSG) glutathione, iron, uric acid, and thiobarbituric acid-reactive substances (TBARs) (lipoperoxidation product), as well as knee extensor/flexor muscle torque peak and average power (isokinetic test), were assessed pre- and post-supplementation with Gln or placebo (30 days). Higher plasma D-fructosamine, insulin, and iron levels, and lower strength/power of knee muscles were found pre-supplementation in the NPE group than in the PE group. Post-supplementation, Gln subgroups showed higher levels of GSH, GSSG, and torque peak, besides lower D-fructosamine than pre-supplementation values. Higher muscle average power and plasma uric acid levels were reported in the PE + Gln group, whereas lower insulin levels were found in the NPE + Gln than pre-supplementation values. TBARs levels were diminished post-supplementation in all groups. Gln supplementation, mainly when associated with physical exercises, improves strength and power of knee muscles and glycemia control, besides boosting plasma antioxidant capacity of elderly women.  相似文献   
8.
Most nutrition studies looking at the association of food with cardiometabolic markers rely on food frequency questionnaires, which are prone to recall bias. Pentadecanoic acid, heptadecanoic acid and trans-palmitoleic acid are fatty acids that are not synthesized endogenously but are obtained from the diet, particularly dairy, making them reasonable biomarkers of dairy consumption. We investigated the association of dairy fatty acid biomarkers with glycated hemoglobin (HbA1c) and cardiovascular risk factors in type 2 diabetes (T2D). In a clinical trial, 111 participants with T2D (age 58.5 ± 8.9 years, HbA1c 8.09 ± 0.96%) were randomized into three groups: a control group that maintained baseline dairy intake, a low-fat (LF) group that incorporated ≥3 servings/day of LF dairy and a high-fat (HF) group that incorporated ≥3 servings/day of HF dairy. We compared the fatty acids (FA) composition between the three groups at 24 weeks. Pentadecanoic acid and trans-palmitoleic acid increased in the HF group by 14.1% ± 5.4% and 17.5% ± 5.1%, respectively, but not in the control and LF groups (p = 0.0474 and p = 0.0025 for group-by-time interaction, respectively). Those increases were positively associated with changes in total cholesterol, very-low-density lipoprotein cholesterol VLDL-C and triglycerides but were not associated with changes in HbA1c from baseline to 24 weeks. These results suggest that the intervention was successful and that participants were likely compliant, which supports the validity of the main trial.  相似文献   
9.
Two districts in Recife (Santo Amaro and Campo Grande) and two districts in Olinda (Sapucaia and Salgadinho), were selected for a comparative study of bancroftian filariasis in Greater Recife. Selection parameters included similar socio-economic, demographic, and endemic levels of lymphatic filariasis. In the districts studied, streets were chosen randomly. These clusters consisted of 110 people each. A population sample was stratified by sex and age: 0-4, 5-9, 10-14, 15-19, 20-29, 30-39, 40-49, 50-59 and 60 years old and over. The parasitological data were obtained by measuring thick blood smears (60 micro l), collected from 8:00 to 12:00 PM and processed and stained with hematoxylin. The data were described in tables, and logarithimic expression graphics were used to analyze parasitic densities. In general, Recife showed a prevalence of 13.5%, and Olinda 12.3%. Mean parasitic densities were 41 and 70 microfilariae/60 micro l (mf/60 micro l), respectively. Higher microfilaremic rates were observed in Recife for the 20-29-year age bracket and in Olinda in the 30-39-year bracket. The authors concluded that the disease has returned to former endemic levels, and the data described call for a reevaluation of control campaigns carried out by the Brazilian National Health Foundation, since the endemic has already reached serious proportions.  相似文献   
10.
Lymphatic filariasis is caused by the nematodes Brugia malayi, Brugia timori, and Wuchereria bancrofti. The disease occurs in developing countries and is more frequent in urban areas. An estimated 4 billion people live in at-risk areas. In Brazil the endemic is caused by W. bancrofti and was first documented in 1878. It was first detected in Recife in 1952. Currently, Recife and Belém are the only cities in Brazil where the endemic is considered a public health problem. The objectives of this study are to discuss the epidemiology and control of lymphatic filariasis and review its control since it was reported by Rachou in 1952. We analyze the "campanhista" or campaign-oriented model employed by the Sucam/FNS institutional program, as well as several proposed innovative methods. We present available strategies for control of filariasis through primary health care services, decentralization to the local level (or "municipalization"), and community-based health programs.  相似文献   
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