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Objective: To assess the regeneration of osteochondral defects in the joint cartilage of the knee induced by autologous platelet-rich plasma (PRP)., Methods: Osteochondral defects produced in the trochlear groove of both knees of ten sheep; defects of the right knees were filled with autologous PRP and the left knees were left unfilled. Macroscopic and microscopic evaluation was carried out 12 week later. The results were evaluated by the total score of both macroscopic and microscopic evaluations comparing the two sides through the Wilcoxon paired test., Results: Macroscopic appearance was not uniform among animals, nor was it different between the right and left knees (p=0.3125), and in no case the regenerated tissue was equal to the normal surrounding cartilage. At histological examination, apparently normal cartilage was not detected in any knee, but a poorly differentiated cartilage was present in 7 right knees, compared to 3 left knees. Fibrocartilaginous tissue was present in most of the remaining knees, with a significant difference in the overall score between right and left knees (p=0.0313)., Conclusion: The PRP as used in this study has reparative properties of the joint cartilage of sheep knees, mostly by stimulating the formation of a fibrocartilaginous tissue. Laboratory investigation.

To possibly reduce postoperative adhesions that occur after ocular myoplasties, we investigated the topical effects of 0.04% mitomycin C on the repaired areas of the medial rectus muscle using an equine renal capsule preserved in 98% glycerin for reinforcement of the sutures. Twenty-four rabbits, divided into two groups of 12 animals each [untreated (control) and treated group (MMC)], were submitted to surgical rupture of the medial rectus muscle of one eye and repair of the defect 24 h later with sutures and an equine renal capsule. Post-operative prophylactic treatment of the two groups consisted of the administration of eye drops containing neomycin, polymyxin B and dexamethasone at regular 6-h intervals for eight consecutive days and daily rinsing with physiological saline. MMC animals received additional treatment with topical 0.04% mitomycin C every 6 h for 14 consecutive days. Slit lamp biomicroscopy showed greater irritation of the ocular surface in MMC animals during the first days post operatively. Adhesions were observed at 15 and 30 days of assessment in the two groups, but were more extensive in control animals at 60 days. Histopathology revealed inflammatory exudation in both groups, which was greater in MMC animals. Mitomycin C (0.04%) instilled at 6-h intervals for 14 consecutive days reduced the occurrence of fibrosis in the myoplastic areas. However, the equine renal capsule was found to be of little benefit for the reinforcement of myoplasties.

Background: Chlorpromazine (CPZ), at high doses, has been shown to protect the central nervous system in experimental models of ischemia and reperfusion. The purpose of this study was: 1) to investigate the protection afforded by different doses of CPZ on the spinal cord of rabbits submitted to ischemia and reperfusion. 2) to correlate the motor impairment of the hind limbs and the percentage of damaged neurons in the anterior horns of the lumbar spinal cord in treated and untreated animals., Methods: Seventy-two New Zealand white rabbits were divided into 6 equal groups (n=12): sham operation, control and 4 study groups. Spinal cord ischemia was obtained by clamping the abdominal aorta caudally to the renal arteries for 30 min, after which it was released and the animals were observed for a period of 48 hrs. The control animals received 3 ml/kg of 0.9% NaCl, i.v., 10 min before aorta clamping. The experimental animals received CPZ, i.v., at doses of 2, 1 and 0.5 mg/kg, 10 min before aorta clamping. In one group 1 mg/kg of CPZ was given 10 min before aorta clamping and the same dose was repeated 2 hrs after the beginning of reperfusion. The spinal cord of the control animals and of those who received one CPZ dose of 2 mg/kg was processed for light microscopy examination., Results: Motor scores of the hind limbs, graded 0 to 4, obtained 48 hrs after the beginning of reperfusion showed that CPZ was effective at doses of 2 and 1 mg/kg. No significant difference was observed with the dose of 0.5 mg/kg. However, the best results were obtained with the dose of 2 mg/kg administered in a fractionated manner. Histological examination revealed that at the dose of 2 mg/kg, CPZ protected a significant number of neuronal cells and that motor recovery hardly occurred when the number of damaged neurons exceeded 50%., Conclusions: 1) The neuroprotective action of CPZ is dose-dependent in the ischemic spinal cord of rabbits. The lower protective dose is 1 mg/kg, which is too high for human beings. 2) There is an inverse correlation between motor recovery and percentage of damaged neurons, and the critical point seems to be between 30% and 50%.

Twelve breast fibroadenomas were analyzed cytogenetically and only four were found to have clonal alterations. The presence of chromosomal alterations in fibroadenomas must be the consequence of the proliferating process and must not be related to the etiology of this type of lesion. In contrast, the few fibroadenomas that exhibit chromosomal alterations are likely to be those presenting a risk of neoplastic transformation. Clonal numerical alterations involved chromosomes 8, 18, 19, and 21. Of the chromosomal alterations found in the present study, only monosomy of chromosomes 19 and 21 has been reported in breast fibroadenomas. The loss of chromosome 21 was the most frequent alteration found in our sample. The study of benign proliferations and their comparison with chromosome alterations in their malignant counterparts ought to result in a better understanding of the genes acting on cell proliferation alone, and of the genes that cause these cells to exhibit varied behaviors such as recurrences, spontaneous regression and fast growth.

Twenty samples of stomach cancers were analyzed by conventional cytogenetic and histopathological techniques. Nineteen tumors were diagnosed as adenocarcinomas and one as an adenosquamous carcinoma. Multiple and complex chromosomal abnormalities were found in the cases evaluated cytogenetically. This heterogeneity of chromosomal changes appears to indicate a certain correlation with tumor progression. Histological analysis showed a distinctive growth pattern of gastric cancer samples and a potential for invasiveness and recurrence for all tumors as well as a poor prognosis.

Accessory breasts are a clearly hereditary anomaly. They enlarge during pregnancy and lactation as a consequence of high blood levels of estrogen and prolactin, and are subject to all the diseases that occur in normal breasts. Cytogenetic analysis was performed on one accessory breast. The monossomy of chromosome 16 was the main alteration found in this material. Nonscheduled cell proliferations may produce chromosome alterations, most of them with no clinical meaning. When relevant genes are altered, major proliferations or progression to malignancy may occur.

Primary intracranial germ cell tumors are the result of the transformation of primordial cells that are unable to migrate to their normal place. These tumors are rare, accounting for less than 5% of all intracranial tumors and less than 3% of childhood neoplasias. In this paper, we have studied cytogenetically two primary intracranial germ cell tumors, a pineal region germinoma, and a mature teratoma in the right lateral ventricle. Neither tumor presented polyploidy or isochromosome 12p, considered to be characteristic of gonadal germ cell tumors. In the five reports in the literature, only one intracranial germ cell tumor presented i(12p). Perhaps i(12p) negative cases characterize a subtype of germ cell tumors.

Cytogenetic analysis was performed on cultures of primary ependymal tumors with different degrees of malignancy (I-IV) obtained from four patients, none of whom had received therapy before karyotypic evaluation. The most common abnormalities were monosomy 17 and 22 in four cases and losses of sex chromosomes in three cases. Structural rearrangements of chromosome 2 were a finding for all cases and involved loss of material at 2q32-34. Other structural chromosome abnormalities detected involved chromosomes 4, 6, 10, 11, 12, and X. We also reviewed data on 22 cases previously reported.

An experimental model of secondary hemochromatosis is described. Saccharated iron was administered i.v. to rats for 7 months in total doses in the range 1.0-1.7 g per kg body weight. After the completion of iron loading, the biochemical measurements revealed elevation of alanine aminotransferase (ALT), slight reduction of plasma glucose concentration, and significant reduction of both plasma and liver ascorbic-acid levels. The mean liver iron concentration was 50 times higher in iron-loaded animals than in controls. High concentrations of inorganic iron were also observed in spleen, pancreas, and heart. Histologic analysis revealed marked hepatic fibrosis in most animals in the experimental group. These results demonstrate this animal model presents some pathologic findings observed in human transfusional hemochromatosis. Additionally, hydroxyl free radicals were detected by electron paramagnetic resonance (EPR) spectroscopy in the iron-overloaded liver tissue processed at pH 5.0. No free radicals were detected at pH 7.4. These results suggest the possible participation of hydroxyl free radicals in the cellular toxicity of iron overload.

The cytogenetic findings based on G-banding in a pineocytoma detected in a 29-year-old woman are reported. The chromosomal study showed numerical alterations involving chromosomes X, 5, 8, 11, 14, and 22, structural alterations of chromosomes 1, 3, 12, and 22, as well as various markers. Tumors of the pineal region are infrequent, and this is the first report of a pineocytoma studied cytogenetically.

Alkaline reflux gastritis is a clinical syndrome that results from a mucosal injury by duodenal contents. In this study, the amount of duodenogastric reflux was assessed in patients who previously underwent proximal gastric vagotomy (PGV group; n = 11) and PGV plus duodenoplasty (PGV+D group; n = 10) as a treatment for duodenal ulcer. The control group (A) consisted of 11 healthy volunteers without endoscopic abnormalities. A quantitative index of duodenogastric reflux was obtained in each case by determining the percentage of the injected dose of 99mTechnetium-DISIDA that was recovered by continuous aspiration of gastric juice in fasting subjects. In the PGV group, the percentage of administered 99mTechnetium-DISIDA recovered from the stomach (median: 0.69%; range: 0.09%-3.61%) did not differ significantly (P > 0.05) from that of the PGV+D group (median: 0.49%; range: 0.09%-3.91%) and from that of the A group (median: 1.47%; range: 0.22%-3.01%). The results show that proximal gastric vagotomy plus duodenoplasty did not increase duodenogastric reflux.

An increased prevalence of chronic gastritis has been reported in patients with chronic Chagas' disease (American trypanosomiasis), which is regarded to be model of intrinsic denervation of the gastrointestinal tract. In order to investigate whether this condition is associated with a reduction of prostaglandin levels in gastric mucosa, we studied 14 Chagas' disease patients with megaesophagus and/or megacolon and compared them with 10 control subjects. All patients and controls underwent an upper gastrointestinal tract endoscopy where biopsies were collected from the antrum for histology and for 6-keto-PGF 1 alpha radioimmunoassay. In the Chagas' disease group, the proportion of patients with either moderate or severe gastritis (7/14) was significantly higher (p < 0.01) than in the control group (0/10). Values for antral 6-keto-PGF 1 alpha in Chagas' disease patients (median: 80.75 ng/g; range 36.5-245.6 ng/g) were slightly lower than those obtained in controls (median: 116.2 ng/g; range: 13.1-269 ng/g), but the difference was not statistically significant (p > 0.10). These results confirm previous observations suggestive of an increased prevalence of chronic gastritis in Chagas' disease, but do not support the view that chronic destruction of the intramural neurons of the gut, which is known to occur in this condition, is associated with a reduction of prostaglandin levels in gastric antral mucosa.

Seventeen consecutive cases of cryptococcal meningitis diagnosed at Hospital das Clínicas of Ribeirão Preto Medical School (São Paulo State Brazil) between 1969 and 1985 were reviewed. For analysis the patients were separated in 3 groups: I. three patients without immunodeficiency; II. six patients with associated disease: cancer (3), diabetes (2) and alcoholism (1); III. Eight renal transplant recipients that developed cryptococcosis after 18 to 67 months of immunosupression with steroids and azathioprine. The median interval between onset of symptoms and diagnosis of infection was greater in Group II (53 days) than in Groups I (25 days) or III (28 days). Neck stiffness, cranial nerve involvement and papilledema were more frequent in Group I than in Group II or III, but fever and focal neurological signs were observed only in patients of two last groups. Cerebrospinal fluid examination showed a mild lymphocytic pleocytosis in most patients, but transplant cases had polymorphonuclear cells more frequently. Late mortality was higher in patients with underlying disease and the prognosis was better for transplant patients that received effective antifungal therapy. Besides cryptococci, autopsy findings in 8 cases revealed granuloma formation in tissues, except in patients of Group II (2 cases). The differences between the groups suggest that clinical characteristics, evolution and postmortem findings of the cryptococcal meningitis are changed according to type of immunodeficiency presented by the patient.

The upper gastrointestinal tract was investigated endoscopically in 30 patients with paracoccidioidomycosis. Esophagus, stomach and duodenum showed, respectivelly, 40%, 53% and 43% of endoscopic alterations. The histopathological examination of biopsy tissue revealed no specific lesions in esophagus and stomach, but P. brasiliensis was observed in three cases of duodenal lesions: two cases with mucosal diffuse erosions and one case of duodenal polyp. It is concluded that duodenal paracoccidioidomycosis is not rare and could be revealed by endoscopic examination in patients with disseminated disease.

Cytogenetic analysis of an untreated sarcomatous meningioma from a patient submitted to two surgeries separated by 1 year are reported. The material from the first surgery was mostly hypodiploid, with a modal chromosome number of 42. Alterations of chromosome 22 were found in 80.6% of the cells. Four chromosome markers were found involving chromosomes 1, 2, 6, and 22, and numerical alterations involving chromosomes 8, 9, 10, 13, 14, 15, 18, 19, 20, 21, and Y. Although the modal chromosome number of the material from the second surgery was 45 (17.9% of the cells), 43.1% of its cells were hyperdiploid, 73% of these being in the triploid-tetraploid range. Dicentric and ring chromosomes were very frequent. Alterations involving chromosome 22 were still present. There was a recurrent trisomy of chromosome 3. To our knowledge, this is the first cytogenetic description, with banding techniques, of a malignant meningioma.

A case of an syphilitic intraspinal gumma is reported. A 48 years-old woman developed severe spastic crural paraparesis of two months duration, associated with sensory and sphincteric disturbances. Myelography revealed an intraspinal tumor at T3 level. Surgical exploration by dorsal laminectomy showed a syphilitic gumma attached to the spinal cord. Clinical observations and laboratory studies are discussed. Revision and comments on previous reports are presented.