Underregistration of neonatal deaths: an empirical study of the accuracy of infantile vital statistics in Taiwan

The purpose of this study was to determine the percentage of peripheral blood T lymphocytes and the localization of ANAE enzyme at the electron microscopic level in Van cats by using an alpha-naphtyl acetate esterase procedure. Peripheral blood samples taken from 20 Van cats were used. The percentage of ANAE positive lymphocytes was 83.0%. Neutrophilic granulocytes gave a negative reaction, whereas monocytes, eosinophilic granulocytes showed a diffuse granular positivity. In the electron microscopic examination, ANAE positive reactions were seen in lysosomal granules found in lymphocytes.     

Ornithine decarboxylase over-expression stimulates mitogen-activated protein kinase and anchorage-independent growth of human breast epithelial cells

Inactivation of one X chromosome (X inactivation) in female mammals results in dosage compensation of X-chromosomally encoded genes between sexes. In the embryo proper of most mammals X inactivation is thought to occur at random with respect to the parental origin of the X chromosome. We determined on the cellular level the expression of the X-chromosomally encoded protein dystrophin in skeletal and cardiac muscle of female mice heterozygous for a null mutation of the dystrophin gene (mdx/+). In all muscles investigated (cardiac, anterior venter of digastric muscle, biceps brachii and tibialis anterior muscle) we found a mosaic expression of dystrophin-expressing versus non-expressing cells and determined their proportion with respect to the parental origin of the X chromosome. In all groups of mdx/+ mice the level and pattern of dystrophin expression were found to be dependent on the parental origin of the mdx mutation. Additionally, the extent of dystrophin expression was clearly dependent on the mouse strains (C57BL/10 and BALB/c) used to produce heterozygous mdx/+ mice. Variable differences and patterns of dystrophin expression in skeletal versus cardiac muscle were found that were strictly dependent on the parental source of the mdx mutation and the strain used to breed mdx/+ mice. Moreover, dystrophin expression was found to be different between the right side and the left side of the body in individual muscles, and this difference was clearly dependent on the parental origin of the X chromosome. Our data provide evidence that in the mouse embryo proper there is a non-random distribution of cells showing inactivation of the paternal versus the maternal X chromosome in skeletal and cardiac muscle, indicating a non-random X-inactivation. Besides gametic imprinting, strain-, tissue and position-dependent factors also appear to bias X inactivation.     

Ornithine decarboxylase and polyamines in familial adenomatous polyposis

The effects of concanavalin A (Con A) on liver cytokine gene expression was studied in mice. The CD4 mRNA expression in normal liver suggests the presence of CD4+ T cells. The administration of Con A induced interleukin (IL)-1beta, IL-2 and IL-2 receptor mRNAs, which implies lymphocyte activation in the liver. Interferon-gamma and tumor necrosis factor-alpha mRNA expressions were increased gradually. The present results showed that Con A induced liver cytokine genes. This cytokine gene induction might have been the result of lymphocyte activation in the liver.     

Amphetamine-induced disruption of latent inhibition depends on the nature of the stimulus

It is well documented that latent inhibition (LI), i.e. slower conditioning to a stimulus that had been repeatedly pre-exposed without consequences, compared to a non-pre-exposed stimulus, is prevented by amphetamine. Recently, we found that the effects of amphetamine on LI, as assessed in an off-baseline conditioned emotional response (CER) procedure, depend on the nature of the pre-exposed stimulus, irrespective of reinforcer intensity. Because these results contrast with a recent finding that a reduction in reinforcer intensity reversed amphetamine-induced attenuation of LI in an on-baseline CER procedure, the present study investigated the effects of amphetamine on LI as a function of the nature of the pre-exposed stimuli and shock intensity, using an on-baseline CER procedure. The effects of amphetamine on post-shock suppression of drinking as well as on activity, were monitored throughout the stages of the CER procedure. Experiment 1 used a 5 s steady light as the pre-exposed and conditioned stimulus, and two shock intensities in conditioning, and Experiment 2 used a 10 s flashing light and two shock intensities. Amphetamine disrupted LI with a steady light at both low and high shock intensities, but failed to disrupt LI with a flashing light at both shock intensities. In addition, the drug disrupted LI in Experiment 3, which increased the duration of the steady light to 10 s and used only low shock intensity, but failed to affect LI in Experiment 4 which used the flashing light on the background of darkness or of light, and only high shock intensity. The effects of amphetamine on LI were not related to its effects on behavioural suppression after footshock, or on activity.     

Achilles tendon rupture. Surgical or non-surgical treatment

Opinions differ about the proper treatment of Achilles tendon rupture. 38 patients with acute total rupture of the Achilles tendon were included in a comparative study of operative as against non-operative treatment. 21 of the patients were treated operatively and 17 non-operatively. The follow-up time was 6-53 months. Three of the non-operated patients but none of the operated group experienced major complications. Ten of the non-operated patients and 14 of the non-operated group experienced minor complications. In the non-operated patients the plantar-flexion range was significantly reduced in the injured foot compared with the other foot (p = 0.03). Because of more re-ruptures and reduced muscle strength in the non-operative group, operative treatment is recommended for active persons. Non-operative treatment may be considered for older people.     

The isolated choroid plexus cyst

A 48-year-old asymptomatic male hepatitis B virus carrier presented with a 2-day history of fever, chills, right upper quadrant abdominal pain, and jaundice. Shock was detected on admission. Emergency abdominal computed tomography (CT) scanning without contrast enhancement showed the features of acute pancreatitis. Hemobilia, edematous pancreatitis, cholestasis and cholecystitis were found on exploratory laparotomy. Neither stone nor active bleeding were detected on intraoperative choledochoscopic examination. Postoperative T-tube cholangiography one month later revealed non-opacification of the left intrahepatic duct. The patient's abdominal pain and hemobilia recurred. Celiac angiography and CT scanning with contrast showed two hepatocellular carcinomas (HCC) in the left lobe of the liver. This is the first case report in the English literature of HCC presenting as jaundice, hemobilia, and acute pancreatitis.     

Patients treated by cardiologists have a lower in-hospital mortality for acute myocardial infarction

Local anesthetics suppress excitability by interfering with ion channel function. Ensheathment of peripheral nerve fibers, however, impedes diffusion of drugs to the ion channels and may influence the evaluation of local anesthetic potencies. Investigating ion channels in excised membrane patches avoids these diffusion barriers. We investigated the effect of local anesthetics with voltage-dependent Na+ and K+ channels in enzymatically dissociated sciatic nerve fibers of Xenopus laevis using the patch clamp method. The outside-out configuration was chosen to apply drugs to the external face of the membrane. Local anesthetics reversibly blocked the transient Na+ inward current, as well as the steady-state K+ outward current. Half-maximal tonic inhibiting concentrations (IC50), as obtained from concentration-effect curves for Na+ current block were: tetracaine 0.7 microM, etidocaine 18 microM, bupivacaine 27 microM, procaine 60 microM, mepivacaine 149 microM, and lidocaine 204 microM. The values for voltage-dependent K+ current block were: bupivacaine 92 microM, etidocaine 176 microM, tetracaine 946 microM, lidocaine 1118 microM, mepivacaine 2305 microM, and procaine 6302 microM. Correlation of potencies with octanol:buffer partition coefficients (logP0) revealed that ester-bound local anesthetics were more potent in blocking Na+ channels than amide drugs. Within these groups, lipophilicity governed local anesthetic potency. We conclude that local anesthetic action on peripheral nerve ion channels is mediated via lipophilic drug-channel interactions. IMPLICATIONS: Half-maximal blocking concentrations of commonly used local anesthetics for Na+ and K+ channel block were determined on small membrane patches of peripheral nerve fibers. Because drugs can directly diffuse to the ion channel in this model, these data result from direct interactions of the drugs with ion channels.     

Chemical shift imaging of particle filtration in sandstone cores

Recent developments have led to increased interest in the application of borehole nuclear magnetic resonance (NMR) as a probe of petrophysical properties. Of particular importance in this connection is the measurement of the longitudinal relaxation time, T1. As T1 is controlled by the pore surface area, its value may be strongly influenced by the invasion of submicron-sized clay particles found in drilling muds. We have studied this effect by the application of phase encode magnetic resonance imaging (MRI) techniques. The extent to which T1 values are affected by particulate invasion is found to depend strongly on the mud characteristics. With thinned spud muds there is a region deep within the core where T1 values are significantly reduced due to an initial spurt of clay particles. In better formulated muds this effect is greatly reduced.