Angiomatoid fibrous histiocytoma of the arm treated by radiotherapy for local recurrence--case report.

The Angiomatoid Fibrous Histiocytoma is a rare tumor of soft tissues, which occurs mainly in children and young adults, with low malignancy grade. It has the capacity of local recurrence, but rarely metastizes. It is frequently difficult to differentiate this from vascular tumors, namely hemangioendotheliomas and angiosarcomas, or simply organized hematomas.

Neurotensin induces calcium oscillations in cultured amacrine cells.

The peptide, neurotensin, is found in a class of amacrine cells synapsing chiefly with other amacrine cells in the chicken retina (Li & Lam, 1990; Watt et al., 1991). To investigate the possible effects of neurotensin, we have used Ca2+ imaging to measure cytosolic Ca2+ concentrations in cultured chick amacrine cells.

Variation in GABA mini amplitude is the consequence of variation in transmitter concentration.

Miniature postsynaptic currents (minis) in cultured retinal amacrine cells, as in other central neurons, show large variations in amplitude. To understand the origin of this variability, we have exploited a novel form of synapse in which pre- and postsynaptic receptors sample the same quantum of transmitter. At these synapses, mini amplitudes measured simultaneously in the 2 cells show a strong correlation, accounting for, on average, more than half of the variance in amplitude.

The kinetics of quantal transmitter release from retinal amacrine cells.

Exocytosis of transmitter at most synapses is a very fast process triggered by the entry of Ca2+ during an action potential. A reasonable expectation is that the fast step of exocytosis is followed by slow steps readying another vesicle for exocytosis but the identity and kinetics of these steps are presently unclear. By voltage clamping both pre- and postsynaptic neurons in an isolated pair of retinal amacrine cells, we have measured evoked synaptic currents and responses to single vesicles of transmitter (minis).

Electrogenic Na-Ca exchange clears Ca2+ loads from retinal amacrine cells in culture.

Calcium influx into cultured retinal amacrine cells is followed by a small, slow, inward current that we show here results from the operation of electrogenic Na-Ca exchange. The activity of the exchanger is shown to correlate with the magnitude of the Ca2+ load and to depend on both the Ca2+ and Na+ gradients. Li+ is unable to substitute for Na+ and in the absence of Na+, slow tail currents are almost entirely suppressed.

Women's narratives in primary care medical encounters.

Objective: This study asked how women's narratives of social and emotional problems are dealt with in primary care encounters. Our conceptual work extended perspectives from narrative analysis to focus on elements of ideology, social control, underlying structure, and features of discourse that appear marginal to medicine's technical tasks.

Method: Based on a critical review of both quantitative and qualitative techniques in research on patient-doctor communication, we developed an interpretive method with criteria to guide sampling, transcription, interpretation, and presentation of findings.

Control of transmitter release from retinal amacrine cells by Ca2+ influx and efflux.

Cultured retinal amacrine cells show quantal GABAergic synaptic transmission. Voltage clamping pre- and post-synaptic cells of an isolated pair has allowed us to examine the entry and removal of Ca2+ at synaptic terminals. Brief presynaptic Ca2+ currents elicit an initial postsynaptic current that probably reflects the roughly synchronous exocytosis of docked vesicles.

Synaptic transmission between pairs of retinal amacrine cells in culture.

We have examined synaptic transmission between isolated pairs of chick GABAergic amacrine cells, maintained in sparse culture and identified by their binding of an amacrine cell-selective antibody. Using the perforated-patch method to whole-cell clamp both cells of a pair, postsynaptic currents were examined for step depolarizations of the "presynaptic" cell. Synaptic transmission, frequently reciprocal, was calcium dependent and reversibly blocked by bicuculline.

The effects of glycine and GABA on isolated horizontal cells from the salamander retina.

1. Horizontal cells, identified by their morphology, were isolated from the salamander retina and examined in whole cell patch clamp. 2.

Dual effect of glycine on horizontal cells of the tiger salamander retina.

1. The effects of glycine on horizontal cells have been examined by microelectrode recording from superfused retinas isolated from the salamander. 2.

Endoscopic papillotomy under ultra-sonographic control.

A new endoscopic method for performing endoscopic sphincterotomy is described. Only after correct positioning of the papillotomy device has been ascertained can papillotomy be carried out. We have used ultra-sonographic examination to confirm the correct placement of the papillotomy device.

The lateral spread of signal between bipolar cells of the tiger salamander retina.

When mapped with a small spot of light, the central receptive fields of bipolar cells in the salamander retina are much larger than the extent of bipolar cell dendrites. Furthermore responses of bipolar cells to distant spots of light are considerably delayed relative to proximal spots. Using quantitative modelling, electrical coupling between bipolar cells is examined and rejected as a sufficient explanation of the data.

Effect of experimental schistosomiasis on 14C-4-cholesterol esterification by mouse liver homogenate.

The effect of experimental schistosomiasis mansoni on cholesterol esterification by mouse liver homogenate was studied using 14C-4-cholesterol. The reaction was carried out in 0.85 ml containing 10 nCi labelled cholesterol (164 nmol as an albumin-stabilized emulsion) with 30 mg tissue homogenate in 176 mM sodium phosphate buffer, pH 7.

Structure of the receptive fields of bipolar cells in the salamander retina.

1. The receptive-field structure of bipolar cells in the salamander retina has been examined using isolated retinae from dark-adapted eyes. 2.

Signal clipping by the rod output synapse.

The properties of synapses between retinal neurons make an essential contribution to early visual processing. Light produces a graded hyperpolarization in photoreceptors, up to 25 mV in amplitude, and it is conventionally assumed that all of this response range is available for coding visual information. We report here, however, that the rod output synapse rectifies strongly, so that only potential changes within 5 mV of the rod dark potential are transmitted effectively to postsynaptic horizontal cells.

Effects of ethanol on postnatal cell acquisition in the rat cerebellum.

Cell generation and cell survival were investigated in the cerebellum of young rats exposed to 10% v/v ethanol in drinking water throughout gestation and lactation. At 12 days postpartum, cell cycle parameters in the external granular layer showed no significant change from control values, and the cell acquisition rate was unaffected. However, the external granular layer appeared thicker in ethanol-treated than in control 12-day-old animals, and a significant increase in cell death in the internal granular layer was observed.

The effect of ethanol on the cellular composition of the cerebellum.

Pregnant Wistar rats were fed on a diet of food pellets and a 10% (v/v) solution of ethanol in water during pregnancy and up to 21 days postnatally. Control groups were given food pellets and water ad libitum. Areal analysis of the cerebellum of neonates showed a significant reduction of 9.

A study of alcohol effects on the brain during gestation and lactation.

Pregnant Wistar rats were maintained on a diet of food pellets and a 10% (v/v) solution of ethanol in water during pregnancy and up to 21 days postpartum. Control groups were given food pellets and water ad libitum. The consumption of food and liquid was monitored throughout this period, so that daily food- and ethanol-derived caloric intake, daily liquid intake, and dose of alcohol ingested could be determined.

Minireview: the health implications of water treatment with ozone.

Ozone is a highly efficient disinfectant which may have significant advantages in water treatment compared to chlorine. It has, however, been shown that mutagenic and possibly carcinogenic byproducts may be produced under certain conditions of ozonation. Light chlorination following ozonization may meet the highest standards of disinfection.