Histomorphometric evaluation of intrahepatic changes following portal overflow in the rat.

Intrahepatic changes after an end-to-side renoportal arteriovenous shunt were studied in 60 rats. Portal and vena caval pressures did not increase from 3 weeks to 1 year. The number and diameters of the portal and hepatic vein lumens were determined through morphometric evaluation to calculate the relative areas. The proportion of area composed by the portal veins increased 3 weeks after shunt creation (P less than 0.001), reaching its highest level at 1 year (0.08% in control rats vs. 2.45% +/- 0.1% at 1 year). The proportionate area for hepatic veins also increased after 3 weeks (P less than 0.001), reaching its highest value by 12 weeks (0.49% in controls vs. 1.73% +/- 0.08% at 12 weeks). Our results suggest that there was a dramatic drop in the intrahepatic vascular resistance, especially at the portal bed, which may have compensated for the portal overflow. The theories regarding forward overflow compensatory mechanisms are discussed.     

Copper, Zinc and Lead Bioaccumulation in Marine Snail, Strombus gigas, from Guacanayabo Gulf, Cuba

Levels of copper, zinc and lead were determined in sediments and edible muscle of marine snail Strombus gigas collected from Guacanayabo Gulf, Cuba. The concentration range of each metal in marine snail muscle on mg kg⁻¹ wet weight varied as follows: Cu = 6.4–32.6, Zn = 20.4–31.1 and Pb = 0.2–2.3; and in corresponding sediments (on mg kg⁻¹ dry weight) as: Cu = 157–186, Zn = 56–94 and Pb = 20–37. The average biota-sediment accumulation factors (BSAFs) obtained for studied metals are less than unity in all cases, indicating that only a little fraction of metal content in the sediments is bioavailable, independently of their possible enrichments in the sediments. The concentrations of copper and lead in some of the marine snails are above typical public health recommended limits.     

Development and use of the lens epithelial explant system to study lens differentiation and cataractogenesis

Over the last two decades much progress has been made in identifying and characterizing many of the molecules involved in understanding normal lens biology and its pathology. Much of this has been made possible through the establishment and use of the lens epithelial explant system. This simplistic tissue culture model, comprised of a sheet of lens epithelium on its native substratum, has been used effectively to study many cellular processes, including lens epithelial cell proliferation, fiber cell differentiation, cell apoptosis as well as epithelial-to-mesenchymal transformation of cells. In doing so, a number of key growth factors and cytokines, including members of the FGF, Wnt and TGFβ family have been shown to play essential roles in many of these cellular events. This has led to further studies exploring the signaling pathways downstream of these molecules in the lens, paving the way for the development of a number of in situ models (primarily transgenic mouse lines) to further explore in more detail the nature of these molecular and cellular interactions. To reciprocate, the lens epithelial explant system is increasingly being used to further characterize the nature of many complex phenotypes and pathologies observed in these in situ models, allowing us to selectively isolate and examine the direct impact of an individual molecule on a specific cellular response in lens cells. There is no question that the lens epithelial explant system has served as a powerful tool to further our understanding of lens biology and pathology, and there is no doubt that it will continue to serve in such a capacity, as new developments are realized and putative treatments for aberrant lens cell behavior are to be trialed.     

Toxicidad en el intestino delgado inducida por 5-fluorouracilo en un paciente con carcinoma colorrectal

5-Fluorouracil-induced gastro-intestinal toxicity predominantly affects the upper and the lower gastro-intestinal tract. Although 5-fluorouracil (5-FU) can cause severe small-bowel toxicity, this has been reported only in 6 patients with colon carcinoma receiving 5-FU-based therapy. The presentation was extensive ulceration and inflammation of the small bowel with no involvement of the colon. We report another case of this toxicity, and discuss the diagnosis and mechanisms by which 5-FU can induce small-bowel toxicity.     

The reassessment of chronic patients previously diagnosed as schizophrenic

Sixty-one outpatients with clinical diagnoses of schizophrenia or schizoaffective disorder were systematically reevaluated with a structured historical diagnostic interview, the Schedule for Affective Disorders and Schizophrenia-Lifetime Version, and with a review of their charts. Research diagnoses were then constructed by applying Research Diagnostic Criteria (RDC) to the interview data and seven diagnostic systems to the chart data. Of the 61 patients, 43 (70.5%) were again recognized to be schizophrenic by the RDC applied to the interview data and 39 (63.5%) met chart criteria. Fifty-one patients (83.6%) were rediagnosed as schizophrenic by at least one of these approaches (excluding the NHSI chart criteria). There was, however, great variation in rediagnostic assignment because of variations in the diagnostic criteria and chart data. Many of the patients who did not meet criteria for schizophrenia met criteria for affective disorder. Patients were assigned to one of four categories according to whether interview or chart rediagnosis was positive or negative for schizophrenia. This categorization was used to search for factors that might account for patients who did not receive a rediagnosis of schizophrenia.     

SMART—An Integrated Wireless System for Monitoring Unattended Patients

Monitoring vital signs and locations of certain classes of ambulatory patients can be useful in overcrowded emergency departments and at disaster scenes, both on-site and during transportation. To be useful, such monitoring needs to be portable and low cost, and have minimal adverse impact on emergency personnel, e.g., by not raising an excessive number of alarms. The SMART (Scalable Medical Alert Response Technology) system integrates wireless patient monitoring (ECG, SpO₂), geo-positioning, signal processing, targeted alerting, and a wireless interface for caregivers. A prototype implementation of SMART was piloted in the waiting area of an emergency department and evaluated with 145 post-triage patients. System deployment aspects were also evaluated during a small-scale disaster-drill exercise.     

An experimental model for the study of hepatic transport and metabolism of toxic compounds.

The usefulness of isolated liver cells for the study of hepatocellular transport and metabolism is demonstrated, using 1-naphthol and 2,2'-dichlorobiphenyl as model compounds. More than 60% of both substances is rapidly taken up by the cells. Naphthol is conjugated with sulphate and with glucuronic acid. These conjugates are released from the cells. Conjugation of dichlorobiphenyl and release of the conjugates is about 25 times slower than that of naphthol.