Release of neuropeptides during intracellular stimulation of single identified Aplysia neurons in culture.

An important criterion for classifying a substance as a neurotransmitter is that it is released in an activity-dependent fashion. We have utilized cell culture of individual neurons of Aplysia to demonstrate the release of the neuropeptides SCPA and SCPB (small cardioactive peptides A and B). Neurons B1 and B2 were isolated from the buccal ganglion of Aplysia and maintained in cell culture. The cells grew new processes, which were immunoreactive to antibodies for the neuropeptide SCPB. These processes contained SCPA and SCPB that were detectable by bioassay on snail heart. The cells synthesized the SCPs from radiolabeled precursors and transported the peptides to their neurites. Single cells released SCPs in a calcium-dependent fashion upon intracellular electrical stimulation. Taken together, these results provide critical evidence that SCPs are neurotransmitters. The results also indicate that the cell culture of individual identified neurons can be used to investigate the release of peptides.     

Antimalarial medications in dermatology. A review

Antimalarial medications are effective for the treatment of a variety of dermatologic conditions. Their use is often curtailed by concern for adverse reactions, including ophthalmologic side effects; however, recent evidence points to a greater margin of safety with these medications than was previously appreciated. This article reviews the pharmacology of antimalarial medications as well as indications and safe guidelines for their use in the treatment of dermatologic conditions.     

Removal of Blue Periocular Lower Eyelid Veins by Ambulatory Phlebectomy

BACKGROUND: Prominent periocular veins, primarily of the lower eyelid, are a relatively frequent cosmetic problem. Reported treatment techniques have included electrosurgical, sclerotherapy, and longer-wavelength lasers. OBJECTIVE: Ambulatory phlebectomy can be performed on reticular veins of the leg. This technique has been applied over the past few years to periocular reticular veins in order to observe the results and side effects. METHODS: Using a hook specifically designed for reticular veins, we treated 10 patients who had larger reticular periocular eyelid veins. One or several punctures with an 18-gauge needle were made in the center of the targeted length of vein. The reticular vein was then gently dissected by undermining with the stem of the Ramelet phlebectomy hook. RESULTS: All 10 patients tolerated the procedure well. In 8 of 10 patients there was complete elimination with a single procedure. Surprisingly, no significant hematoma was seen in any patient, although two patients had a small hematoma lasting less than 1 week. Two patients had only partial success, as a small segment of vein was difficult to extract. This was eliminated with a second phlebectomy performed 2 months later in both cases. Edema that is usually seen after sclerotherapy was not noted in any of these patients. CONCLUSIONS: Ambulatory phlebectomy appears to be a safe and effective means of permanently eradicating periocular veins.     

In situ demonstration of Epstein-Barr viral genomes in viral-associated B cell lymphoproliferations.

Thirteen cases of benign and malignant Epstein-Barr viral (EBV)-associated B cell lymphoproliferations were examined by in situ hybridization studies performed on formalin-fixed, paraffin-embedded tissue sections. EBV nucleic acids were identified in a minority of lymphoid cells in five of six cases of benign infectious mononucleosis studied in tonsil or lymph node specimens. No evidence of EBV was found in two splenectomy specimens from patients with infectious mononucleosis. EBV nucleic acids were identified in one case of fatal, infectious, mononucleosislike immunoblastic proliferation, and were especially concentrated in areas where there were sheets of immunoblasts associated with necrosis. EBV nucleic acids were identified in all four cases of EBV-associated post-transplant lymphoproliferations, including three cases of non-Hodgkin's lymphoma in which a majority of the neoplastic cells contained EBV nucleic acids.     

A rearranged lambda 2 light gene chain retards but does not exclude kappa and lambda 1 expression

Mice transgenic for the lambda 2 light chain of MOPC315 were established. In newborn transgenics (TG), lambda 2 was the only light chain found on B cells. However, by day 21, lambda 2 high kappa low as well as lambda 2 low kappa high double expresser populations were emerging. lambda 2 was found on an increased fraction of serum immunoglobulins (Ig), this fraction declined with age. Correspondingly, kappa and lambda 1 expression was suppressed in young mice but increased with age. In adult mice kappa or lambda 1 were often co-expressed with lambda 2 in single serum Ig molecules. Most B cell hybridomas from and adult TG secreted lambda 2,kappa mixed molecules and had rearranged their kappa chain genes. One lambda 2,lambda 1 hybridoma and even a lambda 2,kappa,lambda 1 hybridoma were also found. In conclusion, isotypic exclusion in lambda 2 TG is complete in newborns but becomes increasingly leaky with age. Antigen probably expands the lambda 2 low kappa high B cell population; this population is most likely the major source of serum Ig in adult lambda 2 TG mice. In contrast, the lambda 2 high kappa low population, a major fraction of which is CD5+ Mu low delta low, appears only infrequently to develop into antibody-secreting plasma cells.     

Insulin binding to trophoblast plasma membranes and placental glycogen content in well-controlled gestational diabetic women treated with diet or insulin,in well-controlled overt diabetic patients and in healthy control subjects

Summary Insulin binding to trophoblast plasma membranes and the placental glycogen content were measured in twelve healthy women, in eleven well-controlled gestational diabetic women who were treated either with diet alone (n=4) or with insulin (n=7) and in 18 women with well-controlled overt diabetes mellitus (six White B; four White C; eight White D). The competitive binding assay was carried out with 22 concentrations of unlabelled insulin. Binding data were analysed by a non-linear direct model fitting procedure assuming one non-cooperative binding site. Maximum specific binding was unchanged in the total collective of gestational diabetic women, but was decreased by 30% in those treated with diet (6.2±2.2%) and increased by 90% in insulin-treated women (16.4±10.2%) as compared to the control subjects (8.7±2.5%). The diet-treated women had only 40% as many and those treated with insulin had more than twice as many receptors compared to control subjects on a per mg protein basis and if expressed per total placenta. In patients with overt diabetes mellitus maximum specific binding (18.5±10.6 %) was higher (p<0.05) due to more receptors compared to control subjects but was similar to the insulin-treated gestational diabetic patients. Maximum specific binding and receptor concentrations did not correlate linearly with maternal plasma insulin levels. Receptor affinities were virtually similar in all groups (1.8·10⁹ l/mol). The placental glycogen content was reduced (p<0.05) to about 80% of that of control subjects in the diet-treated collective, whereas it was unchanged compared to control subjects in the insulin-treated gestational diabetic women despite a 40% increase (p<0.001) of the maternal-to-cord serum glucose ratio. In overt diabetic patients the maternal-to-cord serum glucose ratio and the placental glycogen content were higher (p<0.05) than in the control subjects. We conclude that trophoblast plasma membranes from gestational diabetic women treated with diet alone express less and those from women treated with insulin express more insulin receptors than those from a healthy control group in vitro. These differences could not have been disclosed without consideration of the mode of treatment. Trophoblast plasma membranes from overt diabetic women have more insulin receptors than those from healthy control subjects.     

Modulatory synaptic actions of an identified histaminergic neuron on the serotonergic metacerebral cell of Aplysia

Possible sources of excitatory synaptic input to the serotonergic metacerebral cell (MCC) were determined by stimulating various neurons in the cerebral ganglion. Firing of the previously identified histaminergic neuron C2 was found to produce synaptic input to the MCC. The synaptic input consists of fast excitatory-inhibitory synaptic potentials on a background of a slow EPSP. The slow EPSP appears to be monosynaptic and chemically mediated since it persists in a solution of high divalent cations; broadening of the presynaptic spike enhances the EPSP; the size of the EPSP is a function of the Mg2+ and Ca2+ concentrations of the bathing solution; and the EPSP can be mimicked by application of histamine to the MCC. The slow EPSP, in addition to firing the MCC, can increase the excitability of the cell, even under conditions in which C2 is fired at a rate too slow to produce a measurable EPSP when the MCC is at rest potential. This property appears to be due to the fact that the slow EPSP results from an apparent decrease of membrane conductance so that the size of the EPSP increases markedly as the cell is depolarized, and the EPSP appears to be highly voltage-dependent so that it is small or absent close to the rest potential of the MCC. When the MCC is voltage-clamped, application of histamine to the bath results in an inward current that disappears when the MCC is hyperpolarized. The potential at which the histamine-induced current reverses or disappears is dependent on the concentration of external potassium, suggesting that, at least in part, the slow EPSP is due to a decrease of potassium conductance. The data on C2 are consistent with its being an element of the neuronal system that mediates a state of food arousal in Aplysia.     

Duplications of the alimentary tract. Clinical characteristics, preferred treatment, and associated malformations.

Duplications of the alimentary tract are unusual congenital anomalies that frequently present a diagnostic as well as therapeutic challenge to the surgeon. Because these lesions occur so infrequently, they are often not suspected until encountered intraoperatively. Due to the complicated anatomy and common blood supply shared between the duplication and associated native bowel, appropriate management requires a familiarity with the anatomy and clinical characteristics of this entity. To better define the range of patient characteristics, clinical presentation, and preferred therapy, 20 enteric duplications were reviewed in 17 patients treated at the Children's Hospital Medical Center from 1956 to 1986. Ages of patients ranged from 1 day to 11 years; 60% were less than 2 years of age at initial presentation. Seven duplications in six patients involved alimentary tract structures of foregut derivation (esophagus, stomach, and Parts I and II of duodenum), with a predominance of girls (4 of 6). Most of these patients (67%) presented with moderate to severe acute respiratory distress and a mass present on chest radiograph. In 67% of the patients, the correct diagnosis was established before operation. None required emergency operative intervention. By contrast, 13 duplications in 11 patients were of midgut or hindgut derivation (Parts III and IV of the duodenum, jejunum, ileum, and colon). In this group of patients, 62% of the duplications involved the cecum, 23% involved the ileum, and 16%, the jejunum. Seventy-eight per cent of the patients were boys. The most common symptoms were nausea and vomiting, and the most common sign was a palpable abdominal mass. Emergency operative intervention was required of eight of 11 patients with duplications involving the small bowel and colon. Three patients presented with an intussusception, four with signs and symptoms consistent with acute appendicitis, one with a small bowel obstruction, and two with gastrointestinal hemorrhage due to the presence of ectopic gastric mucosa within the duplication. It was found that two important points must be considered in regard to the management of enteric duplications: (1) the common blood supply shared between the duplication and native bowel must be carefully protected to avoid undue sacrifice of normal bowel, and (2) the presence of heterotopic gastric mucosa in 35% of patients negates internal drainage.(ABSTRACT TRUNCATED AT 400 WORDS)     

Bilateral suprascapular nerve entrapment syndrome due to an anomalous transverse scapular ligament

A rare case is reported of a young woman who suffered from suprascapular nerve entrapment syndrome (SNES) of the right side and two years later developed the same syndrome on the left. At the first operation an anomalous bifid transverse ligament was found and cut. The combination of pressure effect from the congenital defect together with frequent protraction of the shoulder due to her work as a physical education teacher caused triggering of the SNES. The clinical course, electromyographic findings, and differential diagnosis are reported. Cutting of the anomalous ligament on both sides brought relief from pain, weakness, and atrophy of the shoulder muscles, enabling the patient to return to work.