Morphology of the kidney of the platypus (Ornithorhynchus anatinus: Monotremata)

The platypus kidney shows morphological similarities to those of other mammals. Macroscopically, the cortex is easily distinguishable from the fairly wide medulla. Within the medulla, no clear border is observed between the inner and outer zones. Light and transmission electron microscopically, the glomeruli show quite similar architecture to those of other mammals; however, the glomerular lobulation is very clear. The glomerular tufts are rather simple, but capillary lumen varies widely in size, which is one of the unique features of the platypus kidney. The urinary tubule is generally similar to that of human and other mammals in shape and segmentation; however, the staining specificities of histochemical reactions and the shape of epithelial cells of the Henle's loop differ from those of other mammals. The most conspicuous features are: 1) although no protein casts are found in the tubular lumina, epithelial cells of the proximal convoluted tubule (PCT) have numerous electron-dense vesicles as in human nephrotic kidneys; and 2) the platypus Henle's loop consists of the thick epithelial cells similar to the mammalian type nephron of birds. As compared to those of other mammals such as humans and rats, our observations suggest that the platypus kidney is less developed, in terms of evolution.     

Long-term results after liver transplantation for primary hepatic epithelioid hemangioendothelioma

BACKGROUND: Hepatic epithelioid hemangioendothelioma (PHEHE) is a multifocal, low-grade malignant neoplasia characterized by its epithelial-like appearance and vascular endothelial histogenesis. The outcome of 16 patients treated with orthotopic liver transplantation (OLT) is the subject of this report. METHODS: A retrospective study of 16 patients with HEHE (7 men, 9 women) with ages ranging from 24 to 58 years (mean 37 +/- 10.6 years). Follow-up intervals ranged from 1 to 15 years (median of 4.5 years). RESULTS: Actual patient survival at 1, 3, and 5 years was 100, 87.5, and 71.3%, respectively. Disease-free survival at 1, 3, and 5 years was 81.3, 68.8, and 60.2%, respectively. The 90-day operative mortality was 0. Involvement of the hilar lymph nodes or vascular invasion did not affect survival. The 5-year survival of HEHE compares favorably with that of hepatocellular carcinoma at the same stage (stage 4A): 71.3 versus 9.8% (p = 0.001) CONCLUSIONS: The long-term survival obtained in this series justifies OLT for these tumors even in the presence of limited extrahepatic disease.     

General oncologic effects of the laparoscopic surgical approach. 1997 Frankfurt international meeting of animal laparoscopic researchers

The results from the majority of the reviewed studies support the hypothesis that abdominal surgery, performed via either a large incision or CO2 pneumoperitoneum, systemically encourages tumor growth in the postoperative period. A full laparotomy incision appears to have a significantly greater effect than CO2 pneumoperitoneum on postoperative tumor growth. Whether the large tumor observed in the surgical groups are the result of increased tumor cell proliferation or diminished tumor cell death remains unclear. There is some evidence pointing to both mechanisms. The loss of the postoperative tumor growth differences between the open and pneumo animals in the athymic mouse experiment suggests that cell-mediated immune function plays a role in tumor containment. The proliferation study results, however, suggest that other stimulatory influence(s) are also at work. Clearly, much research needs to be done regarding the etiology of these tumor growth differences. Other tumor cell lines need to be studied, and investigations regarding tumor growth in an intra-abdominal location need be performed as well. This body of research suggests that the manner in which the surgeon gains access to the abdominal cavity may have an impact on the propensity of tumor cells to implant, survive, and grow in the period immediately after surgery. If true, this may be the most compelling justification for the use of minimally invasive techniques for the curative resection of malignancies. However, it remains to be proven that human tumors will demonstrate differences in tumor growth similar to those noted in some of these animals models. Furthermore, it is not all clear that slight differences in tumor growth postoperatively will translate into significant differences in long-term survival or recurrence rates. At first glance, the existence of port-site tumors would appear to contradict totally the conclusions of many studies discussed in this synopsis. If laparoscopic methods are associated with decreased rates of tumor growth and establishment, then why do port-site tumors form? This is a complex issue calling for discussion that goes far beyond the scope of this article. However, several brief comment on this topic follow. The etiology of port tumors is unknown, although traumatization of the tumor during mobilization, resection, or removal is likely to play a significant role in the liberation of tumor cells from the primary. A relatively small protective benefit, in terms of slower tumor growth rates in laparoscopic patients, will likely not be sufficient to prevent a large inoculum of viable tumor cells in an abdominal wound from establishing a metastasis. Furthermore, as suggested earlier, the systemic effects on tumor growth may be different from the local (i.e., intra-abdominal or abdominal wound) effects. Finally, the true incidence of port tumors remains unknown. It has not been definitively established that the laparoscopic wound tumor incidence is significantly higher than the open rate, although this is the assumption of most surgeons. Several relatively large recently published laparoscopic series have reported port tumor incidences of 0 to 1.2%, which is in the same "ballpark" as the 0.6 1.0% abdominal wound tumor incidences mentioned in several open colectomy series. Clearly, much more research in this area is needed to understand port tumors better and to reconcile the port tumor results with the systemic tumor growth benefits that may be associated with minimally invasive methods.     

Leukocytes, cell adhesion molecules and ischemic acute renal failure

Ischemic acute renal failure (ARF) is a common clinical syndrome, associated with high morbidity and mortality, for which there is no specific therapy. Polymorphonuclear neutrophils (PMN) recruited during reperfusion have been implicated as mediators of renal parenchymal injury in ischemic ARF. Leukocyte adhesion molecules appear to facilitate PMN recruitment in this setting. Complementary studies using monoclonal antibodies, antisense oligonucleotides and gene "knock-out" indicate that blockade of CD11/CD18 integrins and intercellular adhesion molecule-1 (ICAM-1) attenuates ARF in some experimental models of renal ischemia. These exciting observations may herald the development of novel anti-adhesion strategies for use in human disease.     

The National Cancer Data Base report on gastric carcinoma

BACKGROUND: The National Cancer Data Base (NCDB) represents a national electronic registry system now encompassing almost 60% of incident cancers in the United States. In combination with other programs of the American College of Surgeons Commission on Cancer, the NCDB offers a working example of voluntary, accurate, and cost-effective "outcomes management" on a both a local and a national scale. METHODS: For the accession years 1985-1993, the NCDB has obtained information on demographics, patterns of care, disease stage, treatment, and outcome for a convenience sample of 57,407 gastric carcinoma cases (1.6% of total NCDB cases). In addition to describing trends, this report focuses on 5-year relative survival for a cohort of 1987-1988 cases staged according to the third edition of the American Joint Committee on Cancer's TNM classification, as well as patterns of care for a cohort of 1992-1993 cases. RESULTS: Stage-stratified 5-year relative survival for the 1987-1988 cohort was as follows: IA, 71%; IB, 56%; II, 37%; IIIA, 18%; IIIB, 11%; IV, 5%. Without noteworthy changes in stage distribution, demographics, or other factors, the proportion of patients treated by total gastrectomy is increasing slightly, but proximal gastrectomy for proximal cancers remains surprisingly popular. The proportion of cases receiving postoperative adjuvant treatment has declined slightly. Presumably because of advanced age and/or medical infirmity, a substantial proportion of U.S. patients with disease at every stage receive no treatment for cancer. CONCLUSIONS: This analysis of patterns of care has revealed unexplained variations in treatment and opportunities for improvement. Treatment of the elderly, infirm patient with gastric carcinoma appears problematic.     

Cardiac arrest before repair or extracorporeal membrane oxygenation cannulation does not increase the mortality rate associated with congenital diaphragmatic hernia

Despite recent advances in the management of high-risk congenital diaphragmatic hernia (CDH), mortality remains high. Deaths occur later because infants with inadequate pulmonary parenchyma are treated aggressively but eventually succumb to respiratory failure. In an attempt to identify absolute predictors of mortality the authors examined retrospectively their experience with CDH to determine if cardiac arrest before repair or initiation of extracorporeal membrane oxygenation (ECMO) invariably increased mortality. The authors reviewed the charts of 119 infants who had high-risk CDH treated between 1981 and 1994. They were divided into two groups: those that suffered cardiopulmonary arrest (CA, n = 21) before CDH repair or ECMO cannulation; and those that did not (NCA, N = 98). The authors compared mortality rate, ventilatory parameters, duration of, and complications on ECMO, as well as length of hospitalization between groups. Twenty-one infants suffered CA before initiation of ECMO support or CDH repair. Three infants (14%) suffered CA before arrival at our institution; seven (33%) after, and 11 (53%) both before and after arrival. There was no difference between the CA and NCA groups in terms of birth weight, gestational age, race and gender mix, or pregnancy and delivery complications. Five-minute Apgar scores were significantly lower in the CA group compared with the NCA group (4.6 v 5.7, P = .04). The CA group also had significantly worse "best postductal" blood gas and ventilatory parameters. There was no significant difference in length of hospitalization, time from admission to ECMO cannulation or CDH repair, or incidence of complications while on ECMO between the two groups. CA cases were more likely to require ECMO support (76% v 48%, P = .02) and to stay on ECMO for a more prolonged period than NCA cases (5.8 v 3.8 days, P = NS). However, there was no significant difference in overall survival between CA and NCA cases (43% v 51%, P = NS). Cardiopulmonary arrest before repair of CDH or ECMO cannulation is not a univariate independent predictor of mortality and therefore should not preclude these high-risk infants from maximum intensive care therapy, including ECMO cannulation.     

Elevated plasma testosterone and gonadotropin levels in infertile males with hyperthyroidism

During the time period, 1 July 1969-30 June 1974, a total of 7056 patients were moved on the C-9A Nightingale on an "urgent" or "priority" basis. In support of the request for urgent airlift, an average of 21 C-9A aircraft were launched monthly. The domestic aeromedical evacuation missions were highly flexible and productive, yet inexpensive when compared with other means of moving patients. A means for determining precedence for the pickup and movement of patients is essential for an aeromedical evacuation system. When the patient is properly evaluated and the urgency for flight movement determined, unnecessary, costly, hazardous, or special flights are avoided. More than 50% of the "urgent" patients airlifted during this 5-year span originated in the central part of the United States. The Northeast and Far West were each responsible for less than 10% of the patients requiring urgent evacuation over the same period. More than 50% of the urgent patients moved were in the categories of newborn complications, burns, and neurological problems. During this period, no patient was moved on an urgent basis for a psychiatric problem--aeromedical evacuation simply becomes a very effective tool in ensuring complete health care for seriously ill patients.