Gene expression and cell proliferation in rat liver after 2,3,7,8-tetrachlorodibenzo-p-dioxin exposure.

Recently 4 genes (plasminogen activator inhibitor 2, interleukin 1 beta, clone 1, and clone 141) that are transcriptionally or posttranscriptionally responsive to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) have been cloned from a human skin keratinocyte cell line. We determined whether these genes were expressed in the livers of Sprague-Dawley rats following exposure to TCDD and whether there was a relationship between expression and hepatic cell proliferation. TCDD was administered by using a dose loading/maintenance regimen to achieve rapid quasi-steady-state TCDD liver concentrations of 0.

Stimulation of HIT-T15 insulinoma cells by glyceraldehyde does not require its metabolism.

The addition of the triose D-glyceraldehyde (5-20 mM) to HIT-T15 hamster insulinoma cells caused a rapid, marked depolarisation of the plasma membrane accompanied by a pronounced intracellular acidification, an increase in the cytosolic free calcium concentration [Ca2+]i and enhanced secretion of insulin. D-glyceraldehyde did not reduce the rate of efflux of 86Rb+ from loaded perifused cells. All of the above effects of D-glyceraldehyde were also observed in response to L-glyceraldehyde.

Computer-assisted DREZ microcoagulation: posttraumatic spinal deafferentation pain.

Our data demonstrate that approximately 23-29% of standard dorsal root entry zone (DREZ) microcoagulation procedures fail to relieve pain due to inadequate thermal lesions and that approximately 39% fail due to insufficient superior extent of lesions. The remaining failures are related to inadequate lesion placement, improper selection of patients, and, rarely, posttraumatic spinal deafferentation pain resulting from other non-DREZ mechanisms. Computer-assisted DREZ microcoagulation is a satisfactory procedure to treat intractable posttraumatic spinal deafferentation pain, brachial plexus avulsion pain, and lumbosacral nerve root avulsion pain.

Localized nodular myositis. A paraneoplastic phenomenon.

Localized nodular myositis was recognized in an elderly man six months prior to the diagnosis of Hodgkin's disease. Meticulous search of the muscle specimen failed to disclose tumorous involvement. The possible paraneoplastic nature of localized nodular myositis in this patient is discussed.

Serological detection of Helicobacter pylori by a flow microsphere immunofluorescence assay.

A flow cytometric immunofluorescence assay (FMIA) for the detection of immunoglobulin G antibodies to Helicobacter pylori was developed. A multicomponent antigen was prepared and used to coat carboxylated polystyrene microspheres for reaction with patient sera followed by fluorescein isothiocyanate-labelled goat anti-human immunoglobulin G. The reacted microspheres were collected with a flow cytometer, and fluorescence was quantitated relative to the cutoff value provided by pooled sera from patients in whom H.

Lactate transport in insulin-secreting beta-cells: contrast between rat islets and HIT-T15 insulinoma cells.

The transport of L- and D-lactate into rat pancreatic islets and HIT-T15 insulinoma cells was studied by measuring uptake of 14C-labelled substrate at room temperature and by following changes in intracellular pH (pHi) in islets and HIT-T15 cells loaded with 2',7'-bis(carboxyethyl)-5'(6')-carboxyfluorescein (BCECF). Uptake of L-lactate into HIT-T15 cells was rapid, reaching equilibrium after 5 min with an apparent Km value of 4.8 mM.

Stimulation of insulin secretion by glucose in the absence of diminished potassium (86Rb+) permeability.

Two inhibitors of the nucleotide-sensitive K+ (KATP) channel, tolbutamide and quinine, were utilized in order to assess the role of this channel in glucose-stimulated insulin release from perifused rat islets. In the absence of these drugs, the addition of 15 mM glucose elicited a marked biphasic stimulation of insulin secretion concomitant with a reduction in the rate of 86Rb+ efflux. In the presence of either 500 microM tolbutamide or 100 microM quinine, a reduced rate of efflux of 86Rb+ was observed together with an elevated rate of insulin release.

Choline transport in Fusarium graminearum A 3/5.

Fusarium graminearum A 3/5 possesses a high affinity system (Km = 32 +/- 8 microM; mean +/- SE) for uptake of choline, which was shown to be energy-dependent and constitutive. The maximum rate of choline uptake by this system was repressed by ammonia and glucose, showing a three-fold increase in maximum activity after nitrogen (2 h) or carbon (4 h) starvation. The system was highly specific for choline with only dimethylethanolamine (Ki = 198 +/- 29 microM), betaine aldehyde (Ki = 95 +/- 14 microM) and chlorocholine (Ki = 352 +/- 40 microM) acting as competitive inhibitors.

Traveller's coccidioidomycosis: case report of pulmonary infection diagnosed in Israel.

A 60-year-old temporary Israeli resident travelled to Arizona, developed an influenzalike infection, and returned with a space-occupying lesion in the lung. Since the patient was a heavy smoker, lung cancer was suspected and he was operated on. A granuloma was reported on frozen sections, and Coccidioides immitis was revealed on stained preparations and by microbiological investigation.

2-Ketoisocaproate transport in insulin-secreting cells.

The transport of the nutrient secretagogue 2-ketoisocaproate (KIC) was studied in isolated rat pancreatic islets and in the HIT-T15 insulinoma cell line using an oil-filtration technique. In both islets and HIT-T15 cells, KIC uptake was a slow process, not reaching equilibrium within 10 min KIC transport was not dependent upon Na+ in the medium, was not inhibited by alpha-cyano-4-hydroxycinnamate nor by 2-amino-2-norborane carboxylic acid (BCH) and did not appear to be electrogenic. Evidence was obtained to suggest that KIC uptake occurred via passive diffusion into the cell of the undissociated acid species.

Effects of cyclosporin A on induced HIT cell alkalinization.

We studied whether therapeutic doses of cyclosporin A (CsA) modify the effects of nutrient and non-nutrient stimuli on pHi, in the insulin-secreting beta-cell line HIT-T15. Glucose caused a transient acidification, followed by alkalinization. CsA failed to block this alkalinization.

Familial posterior helical ear pits and Wiedemann-Beckwith syndrome.

Multiple cases of posterior helical ear pits (PHEP) with apparent autosomal dominant inheritance in a very large family are reported. There are at least 2 cases of Wiedemann-Beckwith syndrome (WBS) within this family. Three other instances of familial PHEP and/or WBS are presented.

Giant lymph node hyperplasia (Castleman's disease): a clinical study of eight patients.

We report on 8 patients with giant lymph node hyperplasia (GLNH), diagnosed over a 10-year period. The age of the patients at diagnosis, the clinical presentation and the histological subtype varied, indicating that GNLH is a heterogeneous condition. One case was associated with liver cirrhosis, and in another patient bacterial endocarditis was diagnosed post mortem.

Structural and functional conservation between the high-affinity K+ transporters of Saccharomyces uvarum and Saccharomyces cerevisiae.

In Saccharomyces cerevisiae, high-affinity K+ uptake is dependent upon a 180-kDa plasma membrane protein encoded by TRK1 (c-TRK1) [Gaber et al., Mol. Cell.

The role of RAP1 in the regulation of the MAT alpha locus.

The RAP1 gene of Saccharomyces cerevisiae encodes an abundant DNA-binding protein, also known as GRF1, TBA, or TUF, that binds to many sites in the yeast genome in vitro. These sites define a consensus sequence, [sequence: see text], and deletion analyses of genes that contain this sequence have implicated the involvement of RAP1 in numerous cellular processes, including gene activation and repression. The MAT alpha locus, required for determination of the alpha cell type in yeast cells, contains a RAP1 binding site; this site coincides with the MAT alpha upstream activating sequence (UAS) and is necessary for expression of the two genes encoded by the MAT alpha locus, MAT alpha 1 and MAT alpha 2.

Acute stimulation of pancreatic islets by inhibitors of lactic acid transport.

The transport of L-lactate into rat pancreatic islets and RINm5F insulinoma cells was inhibited by alpha-cyano-4-hydroxycinnamate, alpha-fluorocinnamate, quercetin and by p-chloromercuribenzene-sulphonic acid. The addition of each of these compounds to perifused islets resulted in an immediate, marked stimulation of insulin release. Enhanced insulin secretion was accompanied by a similarly rapid and pronounced increase in the rate of 45Ca2+ efflux from pre-loaded, perifused islets.

Studies of the mechanism of activation of HIT-T15 cells by lactate.

L-Lactate, D-lactate, propionate and acetate (all 20 mM) caused a marked intracellular acidification in HIT-T15 cells loaded with 2'7'-bis(carboxyethyl)-5'(6')-carboxyfluorescein (BCECF), followed by recovery to more alkaline values. The effects of L- and D-lactate, but not propionate or acetate, were inhibited by 5 mM alpha-fluorocinnamate. Both L- and D-lactate caused a marked depolarisation and rise in cytosolic [Ca2+] in HIT cells as assessed by oxonol-V and quin2 fluorescence, respectively.

Na+/H+ exchange is responsible for intracellular pH regulation in insulin-secreting HIT-T15 cells.

The addition of glucose to suspensions of HIT-T15 insulinoma cells caused a small, transient acidification followed by a gradual, progressive alkalinisation, as assessed by the fluorescent pH-sensitive dye 2',7'-biscarboxyethyl-5'-(6')-carboxyfluorescein (BCECF). Treatment of cells with acetate or lactate produced an immediate, marked acidification followed by recovery and a subsequent alkalinisation. In contrast, addition of NH4Cl caused a rapid rise in intracellular pH (pHi) and recovery to resting values.

Chromosome abnormality in Kallmann syndrome.

We report on an individual with Kallman syndrome (KS) and a balanced de novo translocation (7;12)(q22,q24). None of 6 full sibs, 3 half-sibs, or parents have KS or this chromosome translocation. This is the only known report of KS with a chromosome abnormality.

Activation of insulin-secreting cells by pyruvate and halogenated derivatives.

Addition of pyruvate to rat islets perifused in the presence of 5 mM-glucose elicited an immediate pronounced biphasic stimulation of insulin secretion. At lower concentrations of glucose (2.5 mM), only the initial, transient, phase of secretion was observed.

Familial duodenal atresia: a report of two families and review.

We report on 2 families with recurrence of uncomplicated duodenal atresia. The presence of consanguinity in one family, the frequent occurrence of consanguinity in parents of affected children previously reported, and the equal sex ratio suggest autosomal recessive inheritance.

Glucose increases cytosolic calcium concentration and inositol lipid metabolism in HIT-T15 cells.

We have investigated the effects of glucose on cytosolic free calcium concentration in the insulin-secreting cell line HIT-T15. Addition of glucose (10 mM) caused a 20-75% increase in cytosolic [Ca2+] within 5 minutes compared to controls in the absence of glucose. A maximal increase in cytosolic [Ca2+] was obtained with 5 mM glucose.