Glyphosate is an inhibitor of plant cytochrome P450: functional expression of Thlaspi arvensae cytochrome P45071B1/reductase fusion protein in Escherichia coli

Radiofrequency (RF) energy has many advantages in thermal tumor ablation protocols. With the recent development of open MRI systems, interventional MRI procedures, including thermal ablation, have become the focus of great research interest. However, the significant interference between RF generators and MR imagers has prevented simultaneous imaging and RF ablation and, until now, has limited the role of RF-based thermal therapy in interventional MRI. Here, a simple switching circuit designed with consideration of patient safety provides compatibility between open MRI systems and RF thermal lesion generators. The experimental results show that the switching circuit allows imaging during RF ablation and opens new opportunity for MR-guided thermal therapy.     

Apoptosis induced by sulindac sulfide in epithelial and mesenchymal cells from human abdominal neoplasms

A tadpole of bullfrog, Rana catesbeiana, is originally covered with the larval skin over its entire body. Drastic changes arise in both the epidermis and the subcutaneous connective tissue at an early developmental stage, producing the precursor of adult type skin (pre-adult skin). It was found that calcium is a useful probe to detect the region where the precursor formation has occurred because its deposition in the upper part of subcutaneous collagen bundles coincides with the appearance of the pre-adult skin. Whole-mount in situ staining of tadpoles with alizarin red S revealed the initiation site of the premetamorphic transformation of the larval skin into the adult precursor and its ensuing region-dependent expansion. The pre-adult skin first emerged at TK II to III (TK, Taylor and Kollros staging) t lateral sides of the body, which led us to postulate that 'the center for premetamorphic skin transformation' is formed at the specific site in this region. This center moved dorsally and then ventrally, then reached to the most proximal region of the tail, yielding a unique sequential conversion pattern by around TK V when the conversion was completed in the trunk. The present study also visualized the process of the hindlimb skin transformation.     

GB virus C/hepatitis G virus infection among patients with hepatocellular carcinoma in the inshore area of the Yangtze River, China

The latest meeting of the AAMC's Forum on the Future of Academic Medicine, on April 29, 1998, opened with a talk by Francis S. Collins, MD, PhD, director of the National Human Genome Research Institute, who reviewed the significant progress that the Human Genome Project (HGP) has made and speculated on how genetic discoveries and technologies would transform health-related research and ultimately the practice of medicine. The HGP's findings will offer clear improvements in diagnosis and prevention, and eventually in treatments, and the relationship between the academic medical center and the pharmaceutical industry will change--but remain good--as that industry applies the findings of the HGP. He stressed the need for the public and health care providers to develop a greater understanding of genetic issues, and urged changes in medical education to accomplish this. Forum members and Dr. Collins discussed the ethics and economics in patient care resulting from genetic research; forum members also asked whether academic medical centers could profit from genetic research findings. The second speaker was John Eisenberg, MD, administrator of the Agency for Health Care Policy and Research, which fosters health care research and disseminates to clinicians and others the findings of such research. Among other topics, Dr. Eisenberg described the new emphasis on health care outcomes and quality and described how his agency promotes research in these areas. Forum members asked who would pay for the information systems needed to communicate the findings of health services research and also noted that there is an expanding definition of health that places new pressures on already stressed academic medical centers, their missions, and their curricula, which must change. Michael Whitcomb, MD, of the AAMC, noted that the view that medical schools can't change their curricula has been proved wrong, and that 24 medical schools are working with the AAMC's Medical Schools Objectives Project on curricular reform. The forum closed with discussion of a few broader issues affecting academic medical centers.     

Pharmacokinetic parameters of sisomicin

Sisomicin in doses of 1 mg/kg was administered intramuscularly to 10 healthy volunteers, and 1 week later the same volunteers received sisomicin at the same dose intravenously. A peak serum concentration of sisomicin of 3.08 mug/ml was obtained 1 h after intramuscular injection, and a peak serum concentration of 7.12 mug/ml was achieved 30 min after a 30-min intravenous infusion. The sisomicin elimination data were analyzed according to a two-compartment model. Pharmacokinetic parameters derived from the intramuscular and intravenous studies were quite similar.     

Experience with 55 Silon pouches

The application of a Silon pouch usually indicates a desperate if not impossible situation in which the abdominal contents cannot be returned to the abdominal cavity and therefore require some type of covering. Since 1968, we have had experience with 55 Silon pouches in infants and children. Almost all of these pouches were applied to newborns. There were 22 deaths in this series (40%), although 12 of these deaths were in the diaphragmatic hernia group and were almost all due to respiratory failure unrelated to the pouch itself. There were nine deaths in the gastroschisis and omphalocele group (28%) and in all these instances infection (especially Candida) was the underlying cause. While much debate exists as to how the Silon pouch should be handled after its application our series demonstrated that the longer it stayed in place the greater the chance of infection. Furthermore if broad spectrum antibiotics were used for a prolonged period of time, Candida overgrowth of the pouch followed by Candida sepsis and death were almost inevitable.     

Application of rearrangements of T cell receptor gene in the diagnosis of mediastinal T-lymphoblastic lymphoma: a case report

Liver veno-occlusive disease is a severe toxic effect observed after bone marrow transplantation. Clinical manifestations are jaundice, painful liver enlargement, and fluid-sodium retention. Histologically there is non-thrombotic obliteration of the centro-lobular veins associated with centro-lobular necrosis. This severe complication of bone marrow transplantation occurs early and is caused by a toxic processing effect. Incidence is variable, 2 to 50% in reported series, depending on patients, type of marrow provessing and on diagnostic criteria (which hinders comparison between studies). According to most studies, veno-occlusive disease regresses spontaneously. Mortality, depending on the severity of the symptoms, varies from 20 to 50%. Pathogenesis remains under debate: the initial event would occur in the sinusoid endothelium creating a state of local hypercoagulability by release of tissue factors favoring deposit of coagulation factors, especially factor VIII, in the subendothelial region of the veinules. There is also a direct toxic effect on centro-lobular hepatocytes which is further aggravated by ischemia and venous stasis. use of heparin to prevent veno-occlusive disease was proposed by the Besan?on group in 1985 after they observed a low incidence (1 case in 65) in patients who were given low doses of heparin to maintain patent central catheters. The same team confirmed in 1992 the low incidence in a large retrospective series of 444 patients given either an autograft (3 cases in 253 patients, i.e. 1.2%), or an allograft (5 cases in 191 patients, i.e. 2.6%). Two single-center studies, one in Seattle and the other at the Saint-Antoine hospital in Paris, published in 1990 and 1991, did not show any difference in patients given heparin or not. Inversely, a randomized study published by Attal in 1992 including 161 patients showed a significant difference in the incidence of veno-occlusive disease between patients given heparin (2.5%) and those who were not given heparin (13.7%; p < 0.01). All these studies show that with low doses (100-150 U/kg) the risk is very very low. The mechanism of action of heparin would appear to be related to its protective effect on the endothelium rather than its hemostasis effect. The vascular protective effect of prostaglandin E1 suggests it might also be useful in preventing veno-occlusive disease.     

Estrogen modulation: tiered testing for human hazard evaluation. American Industrial Health Council, Reproductive and Developmental Effects Subcommittee

Recent concerns about the potential of certain chemicals to modulate estrogen-regulated processes have led to questions as to how chemicals should be tested for such effects. Therefore, AIHC has developed a comprehensive, resource-efficient, and flexible tiered strategy for estrogen modulation (EM) testing. Levels of evaluation include Tier 0, in which exposure, along with alerts based on structure-activity, persistence, bioaccumulation, and other data, are assessed to prioritize chemicals for preliminary testing. In Tier I, short term in vitro, ex vivo, and/or in vivo assays are used to obtain a preliminary indication of EM potential. Among these, an in vivo response assay is considered the most reliable at this time. However, none of these tests are intended for risk assessment, but rather to aid in choosing chemicals for further testing and in guiding the extent of that testing. Tier II is aimed at risk assessment and involves whole animal tests that contain EM-sensitive end points (e.g., two-generation reproduction study). Tier III consists of hypothesis-driven research reserved for situations where targeted research can reduce levels of uncertainty. This tiered approach provides a framework for the strategic and effective application of EM test methods to address specific information needs on a case by case basis.