Lack of evidence for tissue hypoxia as a contributing factor in anastomotic leak following colon anastomosis and segmental devascularization in rats.

PURPOSE: Current surgical dogma dictates that tissue ischemia and hypoxia are major contributing factors in anastomotic leak despite scant evidence. The aim of this study was to determine if tissue hypoxia is a feature of anastomotic leakage in rats following colon resection and segmental devascularization. METHODS: Rats were randomly assigned to undergo sham operation, segmental colon devascularization alone, colectomy alone, or segmental devascularization plus colectomy. Tissue hypoxia present at the colon anastomosis site across the various treatment groups was determined at sacrifice on postoperative day 6. Pimonidazole HCl was injected 30 min prior to sacrifice. Anastomotic tissues were examined and scored for healing versus leakage using an anastomotic healing score (AHS). Collagen content, hypoxia, enteric smooth muscle and periendothelial stromal patterning, and apoptosis were evaluated histologically. RESULTS: No differences in tissue hypoxia were noted in the 16% of anastomotic tissues with poor healing compared to the remaining 84% of rats whose anastomoses healed well. No significant changes were found in cell death in the submucosa of any group. Consistent with previous findings, poor healing was associated with lower collagen content. Submucosal thickness correlated with increased arteriole diameter (R 2 = 0.25, p < 0.005). CONCLUSIONS: These results demonstrate that tissue hypoxia is not a distinctive feature of anastomotic tissues that fail to heal and leak, even when their blood supply is interrupted. These findings suggest that compensatory factors may mitigate the effects of ischemia and hypoxia during healing of anastomotic tissues and that the process of leakage involves factors beyond their acute effects.

[Perinatal mortality 1 in Colima, Col. Case-control study]. / Mortalidad perinatal 1 en Colima, Col. Estudio de casos y controles.

UNLABELLED: Perinatal mortality 1 (PM1) includes deads occurred from 28th week of gestation to 1st week of extrauterine life. The aim of this study was to describe, from medical records, clinical-epidemiological characteristics of 19 perinatal mortality 19 cases and 36 controls occurred in 1998 at a General Hospital. RESULTS: Interruption of the fetal-placental circulation, cardiopathy and ventricular hemorrhages were the main causes of PM1. There were no differences in cases and controls about maternal age 27.6 +/- 7 vs 28.8 +/- 5 years (p = 0.52), gestational age by amenorrhea: 39.2 +/- 1.4 vs 39.0 +/- 1.4 weeks (p = 0.82) and weight: 2892 +/- 769 vs 3352 +/- 549 g (p 0.03) respectively. In our study, the risk of PM1 was increased when history of one to four parity was present (OR = 4.67, p = 0.03) and was decreased when history of nulliparity was present (OR = 0.21, p = 0.03). Ten cases of 19 were mortinates, nine were hebdomadal deads. There was no difference in their characteristics: maternal age 26.1 +/- 5 vs 29.6 +/- 8 years (p = 0.34), gestational age 37.7 +/- 3 vs 34.1 +/- 3 weeks (p = 0.05) and weight 3025 +/- 699 vs 2780 +/- 853 g (p = 0.53) respectively. Hebdomadal death occurred 44 +/- 5 hours after their born. Results demonstrate the importance of improving prenatal attention particularly on last weeks of gestation, even in normal pregnancies.

[Vital tooth autotransplantation]. / Autotrasplantes dentario vitales.

Ten cases of dental transplants belonging to the authors' set of cases were selected and they proved to be successful according to the factors these authors' believe to be important. The operations were carried out on young patients by transplanting the not fully formed third molar to the place of the first molar, following the technique described in the text. The success of a vital dental autotransplant depends on some factors: the tooth to be transplanted should have completed the amelogenesis so that two thirds of its root and the floor of the pulp chamber are also formed; the receiving alveolus must be prepared before the giving area, thus reducing the time in which the third molar remains dislocated out of its alveolus and the lack of communication between the two surgical beds.

Autogenic tooth transplantation: a report of ten cases.

Modifications in the surgical procedure for transplantation of the unerupted mandibular third molar to the first molar socket are presented, and the clinical and radiographic data on ten cases with a 3-year follow-up are described. The proposed method of treatment makes it possible to stabilize the transplant without a splint by using a suture crossed over the occlusal surface of the tooth.

Oral histoplasmosis associated with HIV infection: a comparative study.

OBJECTIVE: Histoplasmosis is a granulomatous fungal disease caused by Histoplasma capsulatum. The objective of the present paper was to describe the prevalence of oral histoplasmosis (OH) in two services from an endemic area in Argentina between 1991 and 2002 and to compare the clinicopathological profile of OH between HIV-positive and HIV-negative patients. METHODS: About 733 HIV+ (group A) and 14 260 patients (group B) were examined. Clinical diagnosis was confirmed by cytology, biopsy or culture. RESULTS: About 21 (3%) and 10 (0.07%) cases of OH were diagnosed in group A and B respectively. Most patients were male. A total of 90% of patients in group A were <45 years old whereas 70% of group B were more than 45 years old. Palate, gingiva and oropharynx were the most frequent locations. The importance of including histoplasmosis in the differential diagnosis of ulcerated oral lesions in immunocompromised patients was discussed.

Ultrastructural analysis and identification of membrane proteins in the free-living amoeba Difflugia corona

Syntaxin-1 and 25-kDa Synaptosome-associated Protein (SNAP-25) are present in the plasma membrane of several different secretory cell types and are involved in the exocytosis process. In this work, the free-living amoeba Difflugia corona was studied in relation to ultrastructure, structural membrane proteins, and proteins such as Syntaxin-1 and SNAP-25. Our results obtained by scanning electron microscopy in the amoeba without its theca, showed many membrane projections and several pore-like structures. Using immunocytochemistry, we found structural proteins Syntaxin-1 and SNAP-25.