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Background: Nicotine reduces skin-flap survival. Pharmacologic therapy may represent an alternative treatment strategy to counteract nicotine effects in the flap surgery setting. In this study, we have compared the isolated and associated actions of the vasoactive drugs buflomedil and pentoxifylline in the viability of dorsal cutaneous flaps of rats treated with subcutaneous doses of nicotine., Methods: The survival of modified McFarlane skin flaps was assessed on post-operative day 7. Nicotine group received 4 mg/kg nicotine during 40 days pre-operatively and 7 days post-operatively. Nicotine+buflomedil group received nicotine and 6 mg/kg buflomedil 24 h pre-operatively and 7 days post-operatively. Nicotine+pentoxifylline group received nicotine and 20 mg/kg pentoxifylline in 15 pre-operatively and 7 post-operatively days. Nicotine+buflomedil+ pentoxifylline group received nicotine and both drugs administered as above. Control group received daily 1 ml normal saline during 40 days pre-operatively and 7 days post-operatively. Using image analysis, five different flap areas were quantified: Total, preserved, necrotic, ischaemic and viability. Viability areas comprised the sum of ischaemic and preserved areas., Results: Nicotine treated animals had lower percentage of viability areas (60.7% +/- 6.8) than the control group (73.7% +/- 9.5), p=0.016. The percentage of viability areas in the buflomedil (76.4% +/- 11.4), pentoxifylline (74.2% +/- 15.6) and buflomedil+ pentoxifylline (74.0% +/- 9.7) groups were larger than the nicotine group (p=0.002, p=0.011 and p=0.012, respectively). There were no significant differences in the viability areas when drugs were used isolated or in association. We further demonstrated that the increase in the viability area of the buflomedil and pentoxifylline groups (isolated or in association) was due to increase in ischaemic areas., Conclusions: Both drugs equally increased flap survival in nicotine treated animals. Viability areas increased due to larger ischaemic areas, probably as a reflex of the action of these drugs in sites of partial circulatory deficit.

The regional distribution of wall thickness and failure properties in human abdominal aortic aneurysm (AAA) was explored. Three unruptured and one ruptured AAA were harvested as a whole during necropsy. Thickness was measured at about every 1.5 cm(2) wall surface area for an average of 100 measurement sites per AAA. Multiple longitudinally oriented rectangular specimen strips were cut at various locations from each AAA for a total of 48 strips. The strips were subjected to uniaxial extension until failure. Wall thickness varied regionally and between AAA from as low as 0.23 mm at a rupture site to 4.26 mm at a calcified site (median=1.48 mm). Wall thickness was slightly lower in the posterior and right regions. The failure tension (ultimate) of specimen strips varied regionally and between AAA from 5.5 N/cm close to a blister site in the ruptured AAA to 42.3N/cm at the undilated neck of a 4 cm diameter unruptured AAA (median=14.8 N/cm). Failure stress (ultimate) varied from 33.6 to 235.1N/cm(2) (median=126.6N/cm(2)). There was no perceptible pattern in failure properties along the circumference. Failure tension of specimen strips at or close to blisters was mostly low. The rupture site in the ruptured aneurysm had the lowest recorded wall thickness of 0.23 mm with only slightly higher readings within a 1cm radius. The failure tension of the specimen strip close to the rupture site was low (11.1 N/cm) compared to its neighborhood in the ruptured aneurysm.

The aging process causes progressive deterioration in kidney structure and function. Aberrant generation of reactive oxygen species has been implicated in both age-related and ischemia-related tissue injury. Vitamin E (VE), one of the most powerful and effective exogenous antioxidants, prevents lipid peroxidation and protects against the effects of oxidative stress. The objective of this study was to determine the influence of age and VE on post-ischemic acute renal failure (ARF). Young adult, middle-aged and aged male Wistar rats were maintained on three different 30-day diets: Normal, VE absent and VE supplemented. On day 30, urinary protein and serum cholesterol and VE were measured. On day 31, rats were subjected to 60' clamping of the left renal artery plus right nephrectomy. Inulin clearance (InCl) was performed 48 h after renal ischemia. Malondialdehyde (MDA) was measured in the cortex of normal and 48-h post-ischemic kidneys. Urinary protein and serum cholesterol were higher in aged rats than in other rats. With aging, InCl decreased progressively. Vitamin E deficiency aggravated ARF. In middle-aged and aged rats, VE supplementation protected against ARF. In the absence of VE, MDA increased with age. In conclusion, our data suggest that ARF becomes more severe with age and that ischemia/reperfusion injury is exacerbated when antioxidant-scavenging ability of the kidney is impaired by VE deficiency. Supplementation with VE is essential for protecting aging kidneys against ischemic ARF.

Aortoesophageal fistula induced by atherosclerotic thoracic aortic aneurysm is rare, but is usually a fatal disorder, with few survivors reported. We report the case of a 72-year-old man with aortoesophageal fistula successfully treated in a two-stage operation. In the first stage, we performed resection and replacement of the aortic aneurysm with a prosthetic graft in situ, esophagectomy, cervical esophagostomy, and jejunostomy. After the patient recovered well postoperatively, a transmediastinal retrosternal interposition of the stomach was performed, with esophagogastroanastomosis in the cervical area, to re-establish the gastrointestinal tract. We include a discussion of the causes, diagnostic approach, management of the aorta and esophagus, and review of the literature.

Purpose: To determine anatomicomorphological changes in the infrarenal portion of the abdominal aorta, we performed 645 dissections of the segment in corpses undergoing necropsy., Methods: The aortas were removed from the corpses with a surgical technique; by means of a device that we designed, the external diameter of the artery was measured after luminal pressure was reestablished. This way, it was possible to avoid underestimation of the arterial diameter postmortem. The influence of age, sex, body size, arterial hypertension, chronic obstructive pulmonary disease, and coronary disease on the aortic diameter and the influence of different degrees of sclerosis on the infrarenal aorta wall were analyzed. Considering the diameters, aortas were regarded as "normal" when they did not present any ectasia, arteriomegaly, aneurysm, or hypoplasia., Results: The sample involved 645 subjects whose ages ranged from 19 to 97 years (mean age, 55.8 years). Of the 645 subjects, 65.5% (423) were men, 34.5% (222) were women, 81% (523) were white, and 19% (122) were of another race. The diameters of arteries showing no anomalous dilatation (ectasis, arteriomegaly, or aneurysm) varied according to subject age, sex, body length, and the degree of atherosclerosis on the aorta wall (P <.01). Aortic diameters of those subjects with arterial hypertension, coronary disease, and chronic obstructive pulmonary disease were compared with the aortic diameters of control subjects, and significant differences were not shown (P >.05). Twenty-nine aneurysms were found (4.5% prevalence). Four were ruptured aneurysms, and all occurred in aortas with diameters larger than 5.0 cm., Conclusion: The infrarenal aortic diameter enlarges with aging, and this enlargement occurs earlier in men than in women. Those subjects who had a longer body length and advanced sclerosis on the aorta wall had larger aortic diameters. There was a high prevalence of infrarenal aneurysms (4.5%), with rupture found solely in aortas with diameters larger than 5.0 cm.

The contribution of the sternocleidomastoid branch of the occipital artery, superior arterial pedicle (SAP), to the irrigation of the sternocleidomastoid muscle (SCM) was evaluated in fresh human cadavers by injecting Neoprene-latex for minute dissection. From its insertion in the mastoid process of the temporal bone, the SCM was divided into six levels. The Neoprene-latex injected into the SAP reached the upper three levels in all SCMs studied, which corresponds to the middle part of the studied SCM. In 43.3% of the SCM, this branch reached level four and in 36.6%, it reached level five., (Copyright 1999 Wiley-Liss, Inc.)

Ablation of the spleen leads to a significant risk of postsplenectomy invasive sepsis. This concept has become very important in the last three decades because of awareness of the spleen's important role in immunological functions. Hence, this has led many research centers to study hemostasis of the injured spleen in order to preserve its function. The objective of this study is to analyze the use of nylon mesh for preservation of the wounded spleen in the presence or absence of local contamination. Twenty dogs were operated, randomly divided into two groups and followed postoperatively for eight weeks. A standard splenic injury was produced in all animals and hemostasis accomplished by attaching nylon mesh to the organ. Postoperatively, in one of the groups the "wounded organ + mesh" was contaminated with a bacterial count proportional to the animal's weight. The other group was not contaminated, maintaining it as control. Both groups were studied as to interaction of contamination/preservation, i.e., body weight, surgical findings, splenic size and histology, blood and tissue culture and hematological data. The dogs adequately withstood the standardized trauma regardless of local contamination. And the nylon mesh effectively arrested bleeding in all animals. At sacrifice inoculated germs were confirmed in the contaminated group by histological methods or tissue cultures. A cellular infiltrate of lymphocytes and plasmocytes was present close to the mesh only in the latter. The mesh attached to the injured spleen did not lead to abscesses, intrasplenic or intraperitoneal fluid collections. Based on analysis of the data, we can infer that local contamination of the injured spleen and the presence of non-absorbable material (nylon mesh) did not markedly alter the overall behavior of the dogs compared to the uncontaminated group.

Occlusion of the thoracic aorta is meant to improve cerebral and cardiac perfusion in the moribund, exsanguinating trauma patient. Yet clinical and experimental experience shows no evident benefit from this critical maneuver, and hind limb paralysis (HLP) is a feared complication. Our study is intended to verify whether aortic occlusion can decrease further blood loss and therefore be useful during treatment of hemorrhagic shock. Four groups of 10 dogs were submitted to hemorrhagic shock and treated with blood (40 mL/kg) and saline (35 mL/kg). Group I was then submitted to intermittent intra-aortic occlusion (IIAO), Groups II and III to IIAO and to a second bleeding (rebleeding), and Group IV to rebleeding only, without IIAO. All dogs received volume replacement during this rebleeding phase and were kept alive for 8 days. Five dogs died and seven had HLP in the three groups submitted to IIAO. Death and HLP occurred even in the dogs of Group I, which were not submitted to a second bleeding. IIAO reduced blood loss from 139 mL/kg to 48 mL/kg. There were no complications or deaths among the 10 dogs in Group IV. Although efficient in reducing blood loss, IIAO was associated with a 16% mortality and 23% of HLP, whereas volume replacement alone was tolerated without complications or death. We conclude that IIAO is dangerous while treating severe hemorrhagic shock even after volume replacement and hemodynamic stabilization.

A total of 117 differentiated thyroid adenocarcinomas that had been removed by total thyroidectomy were studied. Seventy (60%) were papillary, 36 (30%) were follicular, and 11 (10%) were Hürthle cell adenocarcinomas. The mean length of follow-up was 57.7 months. Adverse prognostic factors according to multivariate analysis were adjacent tissue infiltration (p = 0.0004), histologic type (p = 0.0049), and patient age (p = 0.033). The nuclear DNA content of tumor cells and of morphologically normal adjacent tissue was assessed by image cytometry, and correlations between nuclear DNA content and prognostic factors were examined. Fifty-four (75%) adenocarcinomas were classified as aneuploid, 9 (13%) as diploid, and 9 (12%) as borderline. Thirty-four (60%) specimens of morphologically normal adjacent tissue were classified as aneuploid, 18 (32%) as diploid, and 5 (8%) as borderline. The correlation between tumor ploidy and selected prognostic factors was statistically significant for patient age (p = 0.004) and histologic type (p = 0.033). Despite the fact that ploidy could not be identified as a prognostic factor, we suggest that, because of its correlation with age and histologic type, it might prove prognostic if the number of patients were increased. We also emphasize the importance of evaluating morphologically normal adjacent tissue because of the high rates of aneuploidy in these areas.

An electron microscopic study of the elastic fibre and elastic related fibres of the fascia transversalis of the human inguinal triangle was performed in 20 male patients aged 13 to 81 a with right indirect inguinal hernia submitted to surgical repair. The 3 fibre types comprising the elastic system (oxytalan, elaunin, and elastic fibres) tend to be ordered in a precise manner and sequence among the fibrils, fibres, and collagen fibre bundles, respectively. The present findings show that with aging, there is a decrease in the oxytalan fibres and an increase in the amorphous substance of the elastic fibres. The authors concluded that the decrease in oxytalan fibres as a function of age may be responsible for alteration in the resistance of the transversalis fascia.

Liver failure is a serious complication when small bowel bypass is used for control of obesity. To analyse the changes in liver microscopic morphology and liver fatty acids content, 42 rabbits divided in two groups were studied. The 21 animals of group I had 50% of the distal jejuno-ileum excluded and anastomosed to the cecum. The proximal 50% were anastomosed to the distal 5 cm of the ileum. The 21 animals of group II were used as controls and were submitted to a laparotomy and small bowel manipulation. Liver histology and fatty acids content were studied at the time of these operations and in the 21st postoperative day. No signficant histologic changes were noticed in both groups. A significant decrease in liver fatty acids content was observed in groups I and II. However, the decrease in group II was less pronounced than in group I. This last observation appears to support the theory of liver lipid metabolism impairment after small bowel bypass, even in the absence of obesity.

The authors present the case of a 31 year old woman admitted with abdominal pain, fever, weight loss and malignant hypertension. The ultrasonographic examination showed an image suggesting chronic nephropathy. On the 3rd day of hospitalization an exploratory laparotomy was performed with the diagnosis of acute abdomen. There was purulent peritonitis and a segment of ileum with multiple perforations, which was resected. The anatomopathologic finding of the surgical specimen revealed polyarteritis nodosa. The patient developed multiple organ failure and evolved to death. The difficulty in establishing the diagnosis is commented and, the authors according with some studies suggest treatment with plasmapheresis because the conventional therapy with methylprednisolone and cyclophosphamide proved to be insufficient in severe cases.