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Biomedical subjects

M M Machado

Publications and source records attributed to M M Machado.

17 recordsLinked to original sources

Multicentric pheochromocytoma and involvement of the inferior vena cava.

CONTEXT: Extension of pheochromocytomas to the inferior vena cava is rare. Multicentric tumors are rare as well, being present in up to 10% of cases. Surgery is the treatment of choice because of the long-term survival free of disease. DESIGN: Case report. CASE REPORT: We report on a case of right adrenal pheochromocytoma with extension to the supra-diaphragmatic vena cava, which underwent surgical excision through thoracophrenic laparotomy without the need for cardiopulmonary bypass. In a 6-year follow-up, another pheochromocytoma was found in the infra-renal Zuckerkandl's organ. Complete surgical excision of the tumor was performed by a median laparotomy and complete retroperitoneal dissection. In both cases, the total removal of the pheochromocytoma has been guaranteed by having margins free of tumor and a normal post-operative level of catecholamines. The pathological study revealed a malignant pheochromocytoma with margins free of neoplasia in both specimens.

Adrenal Gland Neoplasms↗

[Causes and prognosis of acute renal failure in elderly patients].

UNLABELLED: The prolonged life span of populations is the obvious reason for an increasing proportion of elderly patients with acute renal failure (ARF). The role of age as a factor indicative of a poor prognosis is a matter of controversy. OBJECTIVE: To evaluate this role we have analyzed the final outcome of elderly patients with ARF treated in our Nephrology Service. MATERIAL AND METHODS: Among 361 ARF cases prospectively studied during a two-year period (January 1995 to December 1996), 130 (36%) occurred in patients over 70 years of age. Etiology, clinical course and prognosis were analyzed. The average age was 76.0 +/- 4.7 years, varying from 70 to 94 years; 84 patients (65%) were male, and surgical causes accounted for 51% of geriatric ARF. RESULTS: The most frequent causes were: ischemic (volume depletion, arterial hypotension, and/or low cardiac output) in 48 patients (38%), sepsis in 40 (312%), nephrotoxic drugs in 46 (35%) and obstructive abnormalities in 10 (7.7%); in other 14 (11%) they were diagnosed more than a causal agent. Oliguria was present in 37. 2% (81 patients), and dialysis was needed in 50 patients (39%). The mortality in the population with age below 70 years was 43% and in the elderly patients was 53.8%; total mortality was similar in both groups of patients (p=0.085). Oliguria, need for dialysis, presence of surgical causes of ARF, and ARF acquired within the intensive care unit were associated with poor prognosis in elderly group. CONCLUSION: We concluded that the percentile of elderly patients with ARF is elevated; they presented mortality about of 50%, and this is not superior to the observed in the youngest population; oliguria, dialysis need, ICU cares and surgery are factors of unfavorable prognostic in these patients.

Acute Kidney Injury↗

Results of the routine use of a modified endoprosthesis to drain the common bile duct after laparoscopic choledochotomy.

BACKGROUND: One hundred eighty-one patients were submitted to laparoscopic common bile duct exploration. METHODS: A transcystic approach was used in 147 patients, choledochotomy in 14, and both in 20. The indications to perform a choledochotomy included stones larger than 20 mm, stones proximal to the cystic duct entrance, and cases in which the transcystic duct approach proved impossible or unsuccessful. RESULTS: The common bile duct was drained by a T-tube in four patients, by laparoscopic sphincterotomy in one, by laparoscopic choledochoduodenostomy in one, and by a 10 Fr endoprosthesis in 28. The stent placement was technically feasible in all patients but one. The biliary drainage was adequate. Mean hospital stay was 2.1 days. Complication was limited to one umbilical infection and one self-limited biliary leak. CONCLUSIONS: The procedure proved to be technically simple, safe, and efficient, and resulted in a low morbidity rate and short hospital stay.

Adolescent↗

Laparoscopic antegrade sphincterotomy.

The technique of laparoscopic antegrade sphincterotomy is described. This procedure was used to clear the common bile duct in 22 selected patients with documented choledocholithiasis. Indications for attempting laparoscopic antegrade sphincterotomy included multiple common bile duct stones, one or more common hepatic or intrahepatic stones, a dilated common bile duct requiring a drainage procedure, and suspicion of papillary stenosis. No major complications or mortality was observed. Mild hyperamylasemia was observed in two patients. However, both were asymptomatic, and serum amylase levels rapidly returned to normal. One patient was noted to have a drop in her hematocrit from a preoperative value of 39% to a postoperative value of 33%. Laparoscopic antegrade sphincterotomy added a mean of 17 min to the operative procedure. The mean postoperative stay was 1.4 days. The results of this study suggest that laparoscopic antegrade sphincterotomy may prove to be a useful modality in selected patients with complicated choledocholithiasis.

Adult↗

Extracellular matrix alterations during endochondral ossification in humans.

Immunohistochemical methods were employed to examine alterations in the cartilage extracellular matrix constituents associated with endochondral ossification in humans. The distributions of chondroitin 4- and 6-sulfate and keratan sulfate proteoglycan (PG) determinants, cartilage PG link protein, collagen types I and II, and fibronectin were determined in iliac crest growth-plate specimens using the avidin-biotin-horseradish peroxidase system. Collagen type II was distributed throughout the growth plate, providing a framework within which chondrocytes divided and formed clusters of differentiating (hypertrophic) cells. The septa between these clusters and their subchondral extensions into underlying bone trabeculae were rich in PG, PG link protein, and collagen type II and resembled the extracellular matrix of reserve cartilage. The territorial matrix associated with the differentiating cells within the clusters contained reduced amounts of collagen type II, PG link protein, and possibly cartilage PG. Collagen type I and fibronectin were detected within the cytoplasm of the maturing and degenerating cells, and fibronectin localized intensely to the pericellular matrix envelopes of these cells. These alterations presumably facilitate the degradation of the matrix associated with the cell clusters by invading vascular tissue, while the septa, which retain the characteristics of more typical cartilage matrix, are not degraded and firmly anchor the cartilage to the subchondral bone.

Adolescent↗

Influence of acute hypophysectomy on the natriuresis of dogs submitted to expansion of the extracellular fluid volume.

Three days after creating an access to the turcica on the sphenoid bone, twelve anesthetized mongrel dogs, after control collections, were submitted to extracellular volume expansion with saline. Thereafter, maintained constant the rate of saline infusion, the dura-mater covering the pituitary gland was incised in all dogs, the hypohysis being removed in seven and remaining untouched in the other five dogs. Pharmacological doses of pitressin, glycocorticoids and mineralocorticoids were administered to all dogs. It was shown, for the same filtered sodium load(p is greater than 0.05), that hypophysectomy produces a significant reduction (p is less than 0.05) in urinary sodium excretion previously elevated by the extracellular volume expansion, while durostomy only, without removal of th hypophysis, did not change (p is greater than 0.05) the rate of sodium excretion. Thus, the pituitary gland could be considered as contributing to natriuresis during extracellular volume expansion, all other factors related to this expansion remaining constant in both, hypophysectomized and sham operated dogs.

Animals↗

Natural and experimental infection of planorbids from the Island of Santa Catarina (Brazil).

Studies of eight localities on the Island of Santa Catarina revealed the presence of three species of the molluscan family Planorbidae: Biomphalaria tenagophila, Drepanotrema cimex and Biomphalaria oligoza, the first one being naturally infected by Cercaria ocellifera, a furcocercaria with morphological characteristics of Cercaria caratinguensis, and by an unknown furcocercaria. Drepanotrema cimex was infected by a furcocercaria with characteristics of C. caratinguensis and by C. macrogranulosa. No natural infection was found in B. oligoza. B. tenagophila showed no susceptibility to the experimental infection by the BH-MG strain of Schistosoma mansoni from Belo Horizonte and maintained at laboratory in B. glabrata snails.

Animals↗

[Protein/creatinine index in isolated samples of urine for evaluation of 24-hour proteinuria].

The correct determination of the 24 hours proteinuria (PU24) in the non-hospitalized patients is frequently subject to collection errors. To overcome this problem it has been proposed the use of the proteinuria ratio (PR), obtained by dividing the concentrations of protein/creatinine in random urine samples. In the present investigation PR and PU24 were correlated in 42 patients (22 male and 20 female), aged between 14 and 63 years. Each patient was submitted to a 2 hours creatinine clearance (Ccr), to determination of PU24 and to evaluation of PR in the urine samples. The measures of PU24 were correlated with the values of PR. On linear regression analysis the equation y = 0,517 + 0,759x was obtained, with r = 0,914, suggesting good correlation between PU24 and PR. Values of r greater than 0,9 were always obtained, independently of the values of Ccr and PU24. The results indicate that PR in random urine samples may be practical and reliable in the follow-up of nephrological patients.

Adolescent↗

[Prevalence of anti-HIV antibodies in dialysis patients].

Patients treated with chronic dialysis have a high risk of acquiring viral infections and blood transfusions are commonly considered to be the vehicle of transmission. In Brazil this source is implicated in infection of 15 percent of patients developing acquired immunodeficiency syndrome (AIDS). So, we evaluated the relative risk of our patients in dialysis becoming infected with human immunodeficiency virus (HIV), the virus associated with the AIDS. An enzyme immunoassay showed 6 of 104 patients on dialysis to have antibodies to HIV. In five infection with HIV was confirmed by Western blot tests. Investigation of other risk factors for AIDS showed that blood transfusion was the most likely cause of contamination. There was no correlation between HIV and HBV infections. Only one patient had leucopenia and low OKT4/T8 ratio and she died 90 days after sorologic diagnosis of HIV infection; the cause of death was encephalopathy and sepsis. Two patients died after 4 and 16 months victims of cardiocirculatory problems (non-AIDS related causes). Three patients remain asymptomatic on chronic hemodialysis 20, 36 and 37 months after diagnosis of HIV infection.

Acquired Immunodeficiency Syndrome↗