Epidermoid carcinoma of the anorectum: Review of 31 cases

Summary Thirty-one cases of epidermoid carcinoma found in 106 cases of carcinoma of the rectum and anal canal are reviewed. Clinical presentation and management are presented. Probable factors in the greater than usual incidence of epidermoid carcinomas of the anorectum are discussed. Indications for radiation therapy, local excision, and abdominoperineal and inguinal block dissection are presented.     

Effects of novel antipsychotics,amisulpiride and aripiprazole,on maternal behavior in rats

Rationale Rat maternal behavior, which entails complex motivational and social factors, is disrupted by the currently available typical and atypical antipsychotics. It is thought that this disruption reflects a side effect of antipsychotics, modeling the neuroleptic-induced negative or deficit state. Amisulpiride and aripiprazole are new atypical antipsychotics with mechanisms of action distinct from the current typical and atypical antipsychotics. The effects of these drugs on maternal behavior have not been explored. Objective In the present study, we systematically examined the behavioral effects of amisulpiride and aripiprazole on maternal behavior in postpartum female rats. Methods Various components of maternal behavior (pup retrieval, pup licking, nest building and pup nursing) were examined repeatedly over a period of 24 h after a single injection of three doses of amisulpiride (10, 30, and 100 mg/kg s.c.) and aripiprazole (3, 10, and 30 mg/kg). Results Amisulpiride at the lower doses (10 and 30 mg/kg) enhanced pup licking, and only at the highest dose disrupted the active components of maternal behavior such as pup retrieval and nest building. Its effect was delayed in onset and prolonged as compared to other antipsychotics. Aripiprazole, even at the highest dose (30 mg/kg) did not impair pup retrieval or pup licking. However, it did disrupt nest building and led to enhanced pup nursing. Conclusions The unique effects of these two drugs may be due to their unique actions at the mesolimbic dopamine synapses. The sparing of the major components of maternal behavior by aripiprazole may be related to its partial agonist effects, whereas the enhancement of pup licking by amisulpiride may be related to its dose-dependent preferential effect on the presynaptic autoreceptors. The potential clinical implications of these findings are discussed.     

Sensitization to amphetamine,but not PCP,impairs attentional set shifting: reversal by a D<Subscript>1</Subscript> receptor agonist injected into the medial prefrontal cortex

Rationale Repeated exposure to psychomotor stimulants can lead to sensitization to their effects, and sensitization has been implicated in the pathophysiology of schizophrenia and drug abuse. These disorders are characterized by cognitive deficits, particularly in prefrontally mediated executive function.Objective The present experiments were conducted to investigate the effects of sensitizing regimens of amphetamine and phencyclidine (PCP) on attentional set shifting.Methods Rats received injections of amphetamine, PCP or saline three times per week for 5 weeks. Four weeks later, rats were trained to dig for food in one of two bowls, each bowl having an odour and a texture. Only one dimension (odour or texture) correctly predicted which bowl was baited. Rats were then tested on a series of discriminations including those requiring an intra-dimensional shift (IDS), an extra-dimensional shift (EDS) or a reversal of previously relevant and irrelevant stimuli.Results Rats sensitized to amphetamine performed normally on the IDS, but were impaired on the EDS, as well as on reversal discriminations. PCP-sensitized rats were unaffected on any of the discriminations. In amphetamine-sensitized rats the deficit at the EDS stage was reversed by infusion of the D₁ receptor agonist SKF38393 into the medial prefrontal cortex (mPFC).Conclusions Results show that the amphetamine-sensitized state impairs prefrontally mediated attentional set shifting. This is consistent with cognitive deficits in schizophrenia and addiction, and with the evidence that amphetamine sensitization is accompanied by functional changes in the mPFC. These results further add to a growing literature showing that activating D₁ receptors in the mPFC improves aspects of cognition.     

Cultured Hippocampal Pyramidal Neurons Express Two Kinds of GABAA Receptors

We combined a study of the subcellular distribution of the alpha1, alpha2, alpha4, beta1, beta2/3, gamma2, and delta subunits of the GABAA receptor with an electrophysiological analysis of GABAA receptor currents determine the to types of receptors expressed on cultured hippocampal pyramidal neurons. The immunocytochemistry study demonstrated that alpha1, alpha2, beta2/3, and gamma2 subunits formed distinct clusters of various sizes, which were colocalized with clusters of glutamate decarboxylase (GAD) immunoreactivity at rates ranging from 22 to 58%. In contrast, alpha4, beta1, and delta subunits were distributed diffusely over the cell soma and neuronal processes of cultured neurons and did not colocalize with the synaptic marker GAD. Whole-cell GABA receptor currents were moderately sensitive to GABAA and were modulated by diazepam. The whole-cell currents were also enhanced by the neurosteroid allopregnanolone (10 nM). Tonic currents, measured as changes in baseline current and noise, were sensitive to Zn2+, furosemide, and loreclezole; they were insensitive to diazepam. These studies suggest that two kinds of GABAA receptors are expressed on cultured hippocampal neurons. One kind of receptor formed clusters, which were present at GABAergic synapses and in the extrasynaptic membrane. The alpha1, alpha2, beta2/3, and gamma2 subunits were contained in clustered receptors. The second kind was distributed diffusely in the extrasynaptic membrane. The alpha4, beta1, and delta subunits were contained in these diffusely distributed receptors. The properties of tonic currents recorded from these neurons were similar to those from recombinant receptors containing alpha4, beta1, and delta subunits.     

Catch-up growth in children with late-diagnosed coeliac disease

Anthropometric parameters and catch-up growth were prospectively evaluated in fifty late-diagnosed children with coeliac disease aged 2.25-10 years after 1-4 years of adhering to a strict gluten-free diet (GFD). The anthropometric parameters were expressed as Z scores relative to National Centre for Health Statistics standards using Epi Info 2000 (weight-for-height Z score (WHZ) and height-for-age Z score (HAZ)). Catch-up growth was evaluated by repeated measures. ANOVA, overall significance by an F test and pair-wise comparisons for estimated marginal means using the least significant difference. At the time of enrolment, no significant difference was observed in WHZ and HAZ between children diagnosed before (group 1) or after (group 2) 4 years of age. On follow-up, HAZ was significantly higher in group 1 after the first and third years of the GFD (P=0.04 and 0.02, respectively), with a non-significant increase after completing 4 years of the GFD (P=0.22). Feeding the GFD resulted in an overall significant (F=3.99, P=0.011) increase in HAZ up to 4 years of follow-up. However, the catch-up in height was incomplete, with stunting in sixteen (55.4%) of twenty-nine children after 3 years and in seven (46.6%) of fifteen children after 4 years on the GFD. Pair-wise comparisons demonstrated a linear catch-up growth during the initial follow-up on GFD. Treatment with the GFD did not result in an overall significant increase in WHZ up to 4 years of follow-up (F=1.01, P=0.42). Our results suggest that, in children with late-diagnosed coeliac disease, treatment with a GFD leads to a normalisation of body mass and a significant but incomplete recovery in HAZ during 4 years of follow-up.     

Calciphylaxis in pediatric end-stage renal disease

Calciphylaxis is a rare, but life-threatening complication of end-stage renal disease (ESRD) that has been reported mostly in adult patients. The exact etiology is unknown, but the disease is commonly associated with a high calcium-phosphorus product and elevated levels of parathyroid hormone (PTH). We herein review the published reports on calciphylaxis in ESRD patients less than 18 years old and report the case of a patient with severe calciphylaxis who presented with lower extremity pain, muscle tenderness and difficulty in walking. The serum PTH was low, and the calcium-phosphorus product was normal. The diagnosis of calciphylaxis was confirmed by a muscle biopsy. Treatment with low calcium peritoneal dialysate and substitution of calcium-based phosphorus binders with sevelamer (Renagel) was unsuccessful. The patients clinical condition progressed to extensive soft tissue calcification and ulcerating skin lesions. Nine months after the onset of symptoms, the patient died of cardiopulmonary arrest.