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51.

Introduction

Idiopathic dilated cardiomyopathy causes great impact but many aspects of its pathophysiology remain unknown.

Objective

To evaluate anatomical and histological aspects of hearts with idiopathic dilated cardiomyopathy and compare them to a control group, evaluating the behavior of the perimeters of the atrioventricular rings and ventricles and to compare the percentage of collagen and elastic fibers of the atrioventricular rings.

Methods

Thirteen hearts with cardiomyopathy and 13 normal hearts were analysed. They were dissected keeping the ventricular mass and atrioventricular rings, with lamination of segments 20%, 50% and 80% of the distance between the atrioventricular groove and the ventricular apex. The sections were subjected to photo scanning, with measurement of perimeters. The atrioventricular rings were dissected and measured digitally to evaluate their perimeters, later being sent to the pathology laboratory, and stained by hematoxylin-eosin, picrosirius and oxidized resorcin fuccin.

Results

Regarding to ventricles, dilation occurs in all segments in the pathological group, and the right atrioventricular ring measurement was higher in idiopathic dilated cardiomyopathy group, with no difference in the left side. With respect to collagen, both sides had lower percentage of fibers in the pathological group. With respect to the elastic fibers, there was no difference between the groups.

Conclusion

There is a change in ventricular geometry in cardiomyopathy group. The left atrioventricular ring does not dilate, in spite of the fact that in both ventricles there is lowering of collagen.  相似文献   
52.
Recurrent herpes labialis is a worldwide life-long oral health problem that remains unsolved. It affects approximately one third of the world population and causes frequent pain and discomfort episodes, as well as social restriction due to its compromise of esthetic features. In addition, the available antiviral drugs have not been successful in completely eliminating the virus and its recurrence. Currently, different kinds of laser treatment and different protocols have been proposed for the management of recurrent herpes labialis. Therefore, the aim of the present article was to review the literature regarding the effects of laser irradiation on recurrent herpes labialis and to identify the indications and most successful clinical protocols. The literature was searched with the aim of identifying the effects on healing time, pain relief, duration of viral shedding, viral inactivation, and interval of recurrence. According to the literature, none of the laser treatment modalities is able to completely eliminate the virus and its recurrence. However, laser phototherapy appears to strongly decrease pain and the interval of recurrences without causing any side effects. Photodynamic therapy can be helpful in reducing viral titer in the vesicle phase, and high-power lasers may be useful to drain vesicles. The main advantages of the laser treatment appear to be the absence of side effects and drug interactions, which are especially helpful for older and immunocompromised patients. Although these results indicate a potential beneficial use for lasers in the management of recurrent herpes labialis, they are based on limited published clinical trials and case reports. The literature still lacks double-blind controlled clinical trials verifying these effects and such trials should be the focus of future research.  相似文献   
53.
54.
The aim of this study was to evaluate the efficacy and the safety of liquid monopolar electrocoagulation in the endoscopic control of major haemorrhage from peptic ulcers. During the 24-month period of the trial, emergency endoscopy was performed on 480 patients consecutively admitted with acute upper gastrointestinal tract hemorrhage. Ulcers were seen in 168 cases (35%). Seventy-eight of these were included in the trial. Active bleeding was present in 21 cases and stigmata of recent bleeding were observed in 57. Immediate hemostasis was achieved in nine of 11 patients with active bleeding ulcers. However, active bleeding can stop spontaneously (as in four of 10 control patients), which reemphasizes the importance of randomized studies. There was a trend toward hemostatic benefit for the electrocoagulation-treated patients with actively bleeding ulcers. In the group of 31 patients with visible vessels, the electrocoagulation treatment reduced significantly both the rate of rebleeding and the emergency surgery. In the group of 26 patients with other stigmata of recent bleeding (fresh or altered clot, or black spots), only in two cases allocated to placebo treatment occurred rebleeding. These patients are at minimal risk of further bleeding. The results offer support to the contention that liquid monopolar electrocoagulation is a safe and effective method of reducing the incidence of further bleeding and emergency surgery. This new technique has the advantages of low cost, easy maintenance, durability, and portability.  相似文献   
55.
We previously reported that subnormothermic machine perfusion (sMP; 20°C) is able to improve the preservation of livers obtained from non-heart-beating donors (NHBDs) in rats. We have compared sMP and standard cold storage (CS) to preserve pig livers after 60 minutes of cardiac arrest. In the sMP group livers were perfused for 6 hours with Celsior at 20°C. In the CS group they were stored in Celsior at 4°C for 6 hours as usual. To simulate liver transplantation, both sMP- and CS-preserved livers were reperfused using a mechanical continuous perfusion system with autologus blood for 2 hours at 37°C. At 120 min after reperfusion aspartate aminotransferase levels in sMP versus CS were 499 ± 198 versus 7648 ± 2806 U/L (P < .01); lactate dehydrogenase 1685 ± 418 versus 12998 ± 3039 U/L (P < .01); and lactic acid 4.78 ± 3.02 versus 10.46 ± 1.79 mmol/L (P < .01) respectively. The sMP group showed better histopathologic results with significantly less hepatic damage. This study confirmed that sMP was able to resuscitate liver grafts from large NHBD animals.  相似文献   
56.
We studied the significance of microcirculation inflammation in kidney transplants, including 329 indication biopsies from 251 renal allograft recipients, who were mostly nonpresensitized (crossmatch negative). Glomerulitis (g) and peritubular capillaritis (ptc) were often associated with antibody‐mediated rejection (65% and 75%, respectively), but were also found in other diseases in the absence of donor‐specific antibody (DSA): T‐cell‐mediated rejection (ptc, g), glomerulonephritis (g) and acute tubular necrosis (ptc). To develop rules for reducing the nonspecificity of microcirculation inflammation and defining the best grading thresholds associated with DSA, we built and validated a decision tree to predict DSA. The decision tree revealed that g + ptc sum (addition of g‐score plus ptc‐score) was the best predictor of DSA, followed by time posttransplant, then C4d, which had a small role. Late biopsies with g + ptc > 0 showed higher frequency of DSA compared to early biopsies with g + ptc > 0 (79% vs. 27%). Microcirculation inflammation in early biopsies was often false positive (antibody‐independent). The decision tree predicted DSA with higher sensitivity and accuracy than C4d staining. Microcirculation inflammation sum score predicted graft failure independently of time, C4d and transplant glomerulopathy. Thus any degree of microcirculation inflammation in late kidney transplant biopsies strongly indicates presence of DSA and predicts progression to graft failure.  相似文献   
57.
OBJECTIVE: To describe a technical modification for constructing a vagina in girls with congenital adrenal hyperplasia caused by 21-hydroxylase deficiency, using a narrower skin base but rich subcutaneous tissue, aiming to obtain both longer and larger vaginal segments with better cosmesis of the external genitalia. PATIENTS AND METHODS: From August 1997 to February 2001, 28 girls (aged 5 months to 17 years) had a neovagina constructed using a posterior-based omega-shaped flap. Twenty-six patients had a low vagina entering into the urogenital sinus and two had a high vagina that entered the urogenital sinus. In those with a high vagina the flap procedure was combined with the Passerini-Glazel technique. All the patients were scheduled for vaginal "calibrations" during the first year after surgery and, according to the result, would then undergo vaginal dilatation. RESULTS: Six children were re-operated; five had plastic surgery to correct genital folds that had regained a scrotal aspect, whereas one with a high vagina developed a urethral stricture, with urinary dribbling and infection, and had the urethra reconstructed. These six children are currently well. No hormone therapy was given to one child for 1 year who is scheduled for further surgery for a re-virilized clitoris. Two patients were lost to follow-up. Up to the last visit, 19 girls had not developed a vaginal stricture and the cosmesis of their external genitalia was deemed good. CONCLUSION: The posterior-based omega-shaped flap enabled both the construction of wider vaginal segments with a low risk of developing stenosis in those with a low vagina, and increased vaginal dimension when associated with the Passerini-Glazel technique for those with a high vagina. However, despite good cosmesis of the external genitalia, the follow-up is too short to confirm whether this technique will meet all the expectations.  相似文献   
58.

Background

Renal transplant is the therapy of choice for patients with chronic renal disease. In recent years, improvement in immunosuppressive drugs reduced early graft loss associated with acute rejection. However, vascular thrombosis, accounting for 5% of early graft loss, can sensitize the recipient for human leukocyte antibodies, reducing the chance for a second transplant. The aim of this study was to identify risk factors for vascular thrombosis in a single transplant center, to design specific prevention protocol.

Methods

This was a retrospective, case-control study. From the Renal Transplant Unit database, we identified 21 cases of vascular thrombosis in recipients of kidneys from deceased donors. Recipients from the contralateral kidney from the same donor, without vascular complications, were assigned to the control group. Data analyzed included donor, recipient, transplant surgery, and post-operative follow-up. The local ethics committee approved the protocol.

Results

Thrombosis and control groups were comparable for recipient characteristics, cold ischemia time, organ side (right or left), and site of arterial anastomosis. We observed an increased risk for vascular thrombosis in kidneys with multiple veins (odds ratio, 11.32; P = .03). Organ retrieval surgery complications, such as vascular lesions or heterogeneous perfusion, despite normal pre-implantation biopsy, were considered risk factors for vascular thrombosis within the first post-operative day (odds ratio, 7.1; P = .03).

Conclusions

In this series, multiple renal vein and organ retrieval surgery complications were risk factors for early vascular thrombosis.  相似文献   
59.
The “J shape” curve linking the risk of poor bone health to alcohol intake is now well recognized from epidemiological studies. Ethanol and nonethanol components of alcoholic beverages could influence bone remodeling. However, in the absence of a solid underlying mechanism, the positive association between moderate alcoholic intake and BMD remains questionable because of confounding associated social factors. The objective of this work was to characterize the short‐term effects of moderate alcohol consumption on circulating bone markers, especially those involved in bone resorption. Two sequential blood‐sampling studies were undertaken in fasted healthy volunteers (age, 20–47 yr) over a 6‐h period using beer of different alcohol levels (<0.05–4.6%), solutions of ethanol or orthosilicic acid (two major components of beer), and water ± calcium chloride (positive and negative controls, respectively). Study 1 (24 subjects) assessed the effects of the different solutions, whereas study 2 (26 subjects) focused on ethanol/beer dose. Using all data in a “mixed effect model,” we identified the contributions of the individual components of beer, namely ethanol, energy, low‐dose calcium, and high‐dose orthosilicic acid, on acute bone resorption. Markers of bone formation were unchanged throughout the study for all solutions investigated. In contrast, the bone resorption marker, serum carboxy terminal telopeptide of type I collagen (CTX), was significantly reduced after ingestion of a 0.6 liters of ethanol solution (>2% ethanol; p ≤ 0.01, RM‐ANOVA), 0.6 liters of beer (<0.05–4.6% ethanol; p < 0.02), or a solution of calcium (180 mg calcium; p < 0.001), but only after calcium ingestion was the reduction in CTX preceded by a significant fall in serum PTH (p < 0.001). Orthosilicic acid had no acute effect. Similar reductions in CTX, from baseline, were measured in urine after ingestion of the test solutions; however, the biological variability in urine CTX was greater compared with serum CTX. Modeling indicated that the major, acute suppressive effects of moderate beer ingestion (0.6 liters) on CTX were caused by energy intake in the early phase (~0–3 h) and a “nonenergy” ethanol component in the later phase (~3 to >6 h). The early effect on bone resorption is well described after the intake of energy, mediated by glucagon‐like peptide‐2, but the late effect of moderate alcohol ingestion is novel, seems to be ethanol specific, and is mediated in a non–calcitonin‐ and a non–PTH‐dependent fashion, thus providing a mechanism for the positive association between moderate alcohol ingestion and BMD.  相似文献   
60.
The purpose of the current study was to compare the workout volume (sets x resistance x repetitions per set) completed during two upper body resistance exercise sessions that incorporated 1 minute versus 3 minute rest intervals between sets and exercises. Twelve trained men completed two experimental sessions that consisted of 5 upper body exercises (i.e. barbell bench press, incline barbell bench press, pec deck flye, barbell lying triceps extension, triceps pushdown) performed for three sets with an 8-RM load. The two experimental sessions differed only in the length of the rest interval between sets and exercises; one session with a 1-minute and the other session with a 3-minute rest interval. The results demonstrated that for each exercise, significantly greater workout volume was completed when resting 3 minutes between sets and exercises (p < 0.05). These results indicate that during a resistance exercise session, if sufficient time is available, resting 3 minutes between sets and exercises allows greater workout volume for the upper body exercises examined.

Key points

  • The length of the rest interval between sets is an important variable when designing a resistance exercise program and may vary depending on the characteristic being emphasized (i.e. maximal strength, hypertrophy, localized muscular endurance, power).
  • Although acknowledged, this variable is rarely monitored precisely in field settings.
  • Previous studies that examined rest interval lengths from 1 to 5 minutes between sets for single exercises demonstrated significant differences in repetition performance and the exercise volume completed.
  • There is a need for further research to compare the workout volume (sets x resistance x repetitions per set) completed over an entire resistance exercise session with different rest intervals between sets.
  • The results of the current study indicate that during a resistance exercise session, if sufficient time is available, resting 3 minutes between sets and exercises allows greater workout volume for the upper body exercises examined.
Key words: Recovery, fatigue, strength, muscle endurance, weight training, strength training  相似文献   
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