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C A Haas

Publications and source records attributed to C A Haas.

At least 37 records · Page 2Linked to original sources
PubMed1998

Hepatotoxicity related to intracavernous pharmacotherapy with papaverine.

OBJECTIVES: To determine the incidence of hepatotoxicity related to self-administration of intracavernous papaverine or papaverine/phentolamine (bimix). METHODS: From October 1994 through June 1996, we retrospectively reviewed the medical records of 71 consecutive patients diagnosed with organic erectile dysfunction (ED) and receiving intracavernous injection therapy. Inclusion criteria were documentation of normal baseline liver function tests (LFTs), a minimum of 6 months of follow-up that included LFTs, at least one self-injection every 2 weeks, and no other prior or concurrent treatment for ED. Thirty evaluable patients satisfied the inclusion criteria and formed group 1. Mean age was 63 years (range 40 to 77), mean follow-up was 18 months (range 6 to 32), and mean number of injections per month was 5.7 (range 3 to 12). An age-matched population of 20 patients (mean age 69 years, range 46 to 90) without ED but with similar comorbid risk factors formed the control group (group 2). All patients in group 2 had routine long-term follow-up of LFTs (mean 52 months, range 10 to 1 14). RESULTS: Two patients (6.67%) from group 1 had elevated LFTs during treatment: one experienced a mild elevation in alanine aminotransferase and the other developed transient elevations of total bilirubin and aspartate aminotransferase 6 months after beginning therapy. Both patients reported a history of alcohol abuse. Both patients remained asymptomatic. Neither patient required discontinuation of therapy. One patient (5%) from group 2 developed an elevation of total bilirubin at a follow-up of 12 months. CONCLUSIONS: Routine monitoring of LFTs is probably unnecessary during intracavernous pharmacotherapy. Patients with a history of alcohol abuse or liver disease, however, should be followed up more closely when papaverine is selected for intracavernous injection. In these patients, LFTs should be obtained before initiating treatment and at 6-month intervals.

Adult↗
PubMed1998

Stimulation of P2Y-purinoceptors on astrocytes results in immediate early gene expression and potentiation of neuropeptide action.

The action of adenosine-5'-O-(2-thiodiphosphate), a non-hydrolysable purine analogue and potent P2Y1-purinoceptor agonist, was studied on immediate early gene expression in rat astrocyte cultures. A rapid and transient increase in c-fos, junB, c-jun and Tis11 messenger RNA was observed in cultured astrocytes after treatment with adenosine-5'-O-(2-thiodiphosphate). Maximal induction of immediate early gene expression was obtained within 30 min of stimulation and c-fos was the most sensitive indicator of P2Y-purinoceptor activation. Calcitonin gene-related peptide has also been shown to be a potent inducer of c-fos messenger RNA in cultured astroglial cells. The combined stimulation of astrocytes with calcitonin gene-related peptide and adenosine-5'-O-(2-thiodiphosphate) resulted in the potentiated expression of c-fos messenger RNA. The superinduction of immediate early gene expression by calcitonin gene-related peptide and extracellular ATP in cultured astrocytes might result from intracellular signal transduction cross-talk, since adenosine-5'-O-(2-thiodiphosphate) was found to increase calcitonin gene-related peptide-induced cyclic AMP accumulation by 35%. Phorbol 12-myristate 13-acetate also increased calcitonin gene-related peptide-evoked cyclic AMP accumulation and led to the induction of immediate early gene expression, suggesting that protein kinase C might be at least in part involved in purinergic cross-talk. Our results demonstrate synergistic roles for extracellular ATP and calcitonin gene-related peptide in the transcriptional activation of astroglial cells.

Adenosine Diphosphate↗
PubMed1998

Axotomy-induced c-JUN expression in young medial septal neurons is regulated by nerve growth factor.

In the present study we investigated the axotomy-induced expression of the proto-oncogene c-jun in young rat medial septal neurons and its regulation by nerve growth factor. First, medial septal neurons were retrogradely labelled by Fast Blue injection into the hippocampus at postnatal day 1 (P1). Rats of different developmental ages (P6, P9, P14, P21, P28 and P42) were then subjected to bilateral fimbria-fornix transection resulting in the axotomy of septohippocampal projection neurons. After the lesion, c-JUN immunoreactivity was observed in the nuclei of axotomized medial septal neurons of all stages examined, suggesting that c-JUN induction is an age-independent feature of axotomized medial septal neurons. Double immunolabelling for choline acetyltransferase and c-JUN or parvalbumin and c-JUN, respectively, revealed that both cholinergic and GABAergic septohippocampal projection neurons express c-JUN after axotomy. In addition, a co-localization of immunostaining for c-JUN and the neuropeptide galanin was found after lesion, as both proteins were induced in the same medial septal neurons following fimbria-fornix transection. Next, the regulation of c-JUN expression in axotomized medial septal neurons was studied in organotypic cultures of the medial septum. Axotomized medial septal neurons in culture did not express c-JUN in contrast to the in vivo situation. With the concept that nerve growth factor suppresses c-JUN expression, slice cultures of the medial septum were treated with antibodies against nerve growth factor. This treatment caused a dose-dependent increase in c-JUN-positive cells in these slice cultures. Simultaneous addition of nerve growth factor and antibodies against nerve growth factor resulted in the reversal of this effect. These data suggest an age-independent induction of c-JUN in axotomized medial septal neurons and its regulation by nerve growth factor.

Acetylcholine↗
PubMed1998

Use of ureteral stents in the management of major renal trauma with urinary extravasation: is there a role?

Five patients with major (Grade IV) renal trauma required ureteral stent placement to facilitate urinary drainage. Three of these patients had stents placed for recurrent gross hematuria with flank pain. All three had obstructing blood clots present at the time of stent placement. The fourth patient had a stent placed because of persistent extravasation at 2 weeks postinjury. The last patient was considered at risk for persistent urinary extravasation because of a partial ureteropelvic junction obstruction and had a ureteral stent placed as part of the initial management. All patients were followed radiographically for resolution of extravasation. Long-term clinical follow-up consisted of serum creatinine evaluation and blood pressure monitoring. Urinary extravasation resolved in all five patients, as determined by radiologic evaluation, at a mean of 8 days after stent placement. Ureteral stents were left indwelling an average of 4 weeks. No patient developed hypertension, and all serum creatinine values were normal at a mean 26 months' follow-up. No patient developed urinoma or abscess, and none required open surgical exploration. Ureteral stents may be used safely and effectively to treat persistent or recurrent urinary extravasation resulting from major blunt renal trauma in appropriately selected patients. In addition, ureteral stents may avoid the need for surgical exploration in patients with Grade IV renal trauma who develop recurrent gross hematuria, flank pain, and persistent or recurrent extravasation secondary to clot obstruction.

Adolescent↗
PubMed1998

Traumatic renal artery occlusion: a 15-year review.

BACKGROUND: To better define what constitutes appropriate treatment for traumatic renal artery occlusion, we report our 15-year experience in managing this injury. METHODS: A retrospective chart review was performed to evaluate treatment outcomes and complications of 12 patients (13 injuries) who presented to our trauma centers with renal artery occlusion secondary to blunt injury. RESULTS: Five of 12 patients underwent attempted surgical revascularization with a median warm ischemia time of 5 hours (range, 4.5-36 hours). Of these five patients, one required nephrectomy for inability to establish arterial flow, three demonstrated no function, and one had return to 9% differential function on postoperative renal scan. Seven patients did not have attempted revascularization, and none of them experienced immediate complications. Hypertension developed in three patients (43%) who required nephrectomy to control blood pressure at a mean of 5 months after injury (range, 3-7 months). Four patients remained asymptomatic and normotensive at a mean follow-up of 11 months (range, 4 weeks to 2.6 years). CONCLUSION: Surgical revascularization for traumatic renal artery occlusion seldom results in a successful outcome. Patients who are observed must have close follow-up for hypertension.

Adolescent↗
PubMed1998

Traumatic renal artery occlusion: a review of the literature.

To better define what constitutes appropriate treatment for traumatic renal artery occlusion, we analyzed our experience along with 147 other case reports from the literature. We recently reported our 15-year experience with 12 patients (13 injuries) who presented to our trauma centers with renal artery occlusion secondary to blunt trauma. This experience prompted a review of the literature. From this review, we identified an additional 19 cases of bilateral and 128 cases of unilateral renal artery occlusion that met our inclusion criteria. Of the 20 patients with bilateral renal artery occlusion, surgical revascularization was attempted in 16 and successful in 9 (56%). Of the 139 patients with unilateral renal artery occlusion, surgical revascularization was attempted in 34 and successful in 9 (26%). Evidence of decreased renal function was noted in 67% of those who had a successful revascularization for unilateral injury at a mean 1.8-year follow-up, whereas 12% experienced hypertension at a mean 3.1-year follow-up. Hypertension developed in 34 (32%) of the 105 patients who did not have revascularization attempted and was present by a mean 97 days postinjury. Surgical revascularization for unilateral renal artery occlusion seldom results in a successful outcome. Revascularization is indicated in patients with bilateral renal artery occlusion and in those with injury to a solitary kidney. Patients who are observed must be followed closely for development of hypertension.

Abdominal Injuries↗
PubMed1997

Basal expression, subcellular distribution, and up-regulation of the proto-oncogene c-JUN in the rat dentate gyrus after unilateral entorhinal cortex lesion.

The expression of the transcription factor c-JUN was investigated in the rat fascia dentata under normal conditions and after entorhinal cortex lesion. As shown by immunocytochemistry and in situ hybridization histochemistry c-JUN and its messenger RNA are present in the principal cell layers of the dentate gyrus and Ammon's horn (except hippocampal region CA2). Pre-embedding immunogold electron microscopy revealed an almost exclusive nuclear localization of c-JUN, where it is associated with chromatin. In addition, double immunolabelling for c-JUN and parvalbumin demonstrated that c-JUN immunoreactivity is primarily found in principal neurons since GABAergic parvalbumin-positive interneurons did not express c-JUN. After unilateral electrolytic lesion of the entorhinal cortex c-JUN was strongly up-regulated in the ipsilateral dentate gyrus within 2 h postlesion. This up-regulation was also present in the contralateral fascia dentata 12 h after entorhinal cortex lesion and returned to control levels on both sides 24 h postlesion. The cellular distribution of c-JUN did not change after entorhinal cortex lesion: parvalbumin-positive interneurons never contained c-JUN. These results point to a specific role of c-JUN in the granule cells of the fascia dentata in the normal animal and in rats with entorhinal cortex lesions. The selective induction of c-JUN after entorhinal lesion could be one of the first molecular steps that regulate transneuronal changes within granule cells after their denervation. A different mechanism has to be assumed for GABAergic interneurons known to receive an entorhinal innervation as well.

Animals↗
PubMed1997

Up-regulation of astrocyte-derived tenascin-C correlates with neurite outgrowth in the rat dentate gyrus after unilateral entorhinal cortex lesion.

The extracellular matrix protein tenascin-C has been implicated in the regulation of axonal growth. Using unilateral entorhinal cortex lesions, which induce a massive sprouting response in the denervated outer molecular layer of the rat fascia dentata, the role of tenascin-C for axonal growth was investigated in vivo. Monoclonal antibodies against the neurite outgrowth and anti-adhesive domains of the molecule were employed. Immunostaining was increased throughout the denervated outer molecular layer by day 2, reached a maximum around day 10, and was back to control levels by four weeks post lesion. Growth cone deflecting as well as neurite outgrowth promoting isoforms of tenascin-C were up-regulated after the lesion. Using electron microscopy, single intensely tenascin-C immunoreactive cells were identified as reactive astrocytes that phagocytose degenerated terminals. In situ hybridization histochemistry for tenascin-C messenger RNA revealed numerous cellular profiles in the denervated outer molecular layer of the ipsilateral and contralateral dentate gyrus two days post lesion. Tenascin-C messenger RNA-positive cells in the outer molecular layer were identified as astrocytes using double-labelling for tenascin-C messenger RNA and glial fibrillary acidic protein immunohistochemistry. Thus, a tenascin-C-rich substrate is present in the outer molecular layer during the time of sprouting and a sharp boundary is formed against the inner molecular layer. This pattern may contribute to the layer-specific sprouting response of surviving afferents after entorhinal lesion. Neurite outgrowth may be promoted within the denervated zone, whereas axons trying to grow into the denervated outer molecular layer, for example from the inner molecular layer, would be deflected by a tenascin-C-rich barrier.

Animals↗
PubMed1996

Selective expression of the immediate early gene c-jun in axotomized rat medial septal neurons is not related to neuronal degeneration.

In the present study, we use the anatomically well defined septohippocampal projection to study the molecular events involved in the reaction of neurons to axotomy. The expression of three immediate early genes (c-fos, c-jun, and jun B) was investigated in rat septohippocampal neurons after axotomy by bilateral fimbria-fornix transection (FFT). Moreover, the extent of retrograde degeneration in the septal complex was assessed by analyzing DNA fragmentation. In a postoperative time course analysis, a strong increase of c-jun immunoreactivity (IR) was observed in the nuclei of neurons in the medial septum/diagonal band complex (MSDB) 2 and 6 d postaxotomy, which was followed by a decline after 12 d and 3 weeks, respectively. Nine weeks after FFT, c-jun IR had disappeared. The c-jun-positive MS neurons were identified as former septohippocampal projection cells by double-labeling with the retrogradely transported tracer Fluoro-Gold injected into the hippocampus before axotomy. In line with the immunocytochemical data, there was a massive induction of c-jun mRNA in the axotomized MS neurons as visualized by in situ hybridization histochemistry. c-fos mRNA and c-fos or jun B IR were not detectable in either unoperated or lesioned medial septal neurons. Experiments using the TdT-mediated deoxyuridine triphosphate nick-end-labeling technique, designed to detect nuclear DNA fragmentation in degenerating neurons, complemented this study. During the postoperative time range studied, MS neurons did not exhibit DNA fragmentation. We conclude that MSDB neurons survive axotomy by FFT and display characteristic changes in gene expression.

Acetylcholine↗
PubMed1995

Calcitonin gene-related peptide and ATP induce immediate early gene expression in cultured rat microglial cells.

Factors affecting gene expression in microglial cells were investigated using the induction of immediate early genes in cultured microglia as a model. In particular, the actions of calcitonin gene-related peptide (CGRP) and ATP, both of which have been proposed as signalling molecules in the activation of glial cells, were evaluated using Northern blotting and in situ hybridization methods. In the presence of CGRP, c-fos and junB mRNAs accumulated in microglial cultures, whereas no significant change in c-jun and TIS11 mRNAs occurred. A similar pattern of immediate early gene activation was obtained when adenylate cyclase was stimulated with forskolin. CGRP also stimulated cyclic AMP accumulation with a half-maximal effect in the range 2-5 nM, suggesting a possible role for cyclic AMP as a mediator of the effects of CGRP on gene expression. In contrast to the selective induction of c-fos and junB by CGRP and forskolin, ATP led to the accumulation of all four immediate early genes studied, i.e., c-fos, junB, c-jun, and TIS11. Similar results were obtained when protein kinase C was stimulated with phorbol ester indicating that the induction of immediate early gene expression by ATP and CGRP involves different intracellular mechanisms. The action of ATP was mimicked by ADP and the poorly hydrolyzable analogues, ADP beta S and 2-methylthio ATP, but not by beta, gamma-methylene ATP, AMP, or adenosine, indicating that the receptor mediating the actions of ATP on microglial gene expression is probably of the P2Y-purinoreceptor type. The results suggest roles for CGRP and ATP as transcriptional activators in microglial cells.

Adenosine Triphosphate↗
PubMed1995

Evaluation of a potassium chloride extract of Brucella abortus in an ELISA for detecting Brucella antibodies in bulk tank milk samples from cows.

An enzyme-linked immunosorbent assay (ELISA) was developed using as antigen a potassium chloride extract of Brucella abortus strain 1119-3 for detecting Brucella antibodies in bulk tank samples of cow's milk. Three-hundred-thirty-four Milk Ring Test (MRT) suspicions milk samples originating from cattle herds in 13 states and 106 BRT negative milk samples were analyzed. Fifty-four of 334 MRT suspicious milk samples were positive on ELISA; bacteriologic examinations revealed B. abortus field strain was isolated from cows in 15 herds, B. abortus strain 19 was isolated from cows in 16 herds and serologic suspects were reported in 6 of the other 23 herds. Two-hundred-fifty-eight (85.6%) of the 301 MRT suspicious samples were negative on ELISA; field investigations and/or serologic tests on cattle failed to disclose Brucella infection in these herds. Suspicious ELISA reactions were detected in 22 MRT suspicious bulk tank milk samples; serologic suspects were reported in 8 of the 22 herds. No false positive ELISA reactions were detected in the 106 MRT negative bulk tank milk samples collected from dairy herds in 7 states.

Animals↗
PubMed1994

Constitutive upregulation of calcium channel currents in rat phaeochromocytoma cells: role of c-fos and c-jun.

1. Northern blot analysis and cell transfection were used in conjunction with whole-cell current recordings to examine the involvement of the immediate early genes, c-fos and c-jun, in the expression of calcium channel currents. 2. Phaeochromocytoma cells (PC12 clone) were exposed to nerve growth factor (NGF) and to depolarizing concentrations of KCl for 60 min every day. Cells challenged with NGF developed extensive networks of neurites within 3 days. Cells depolarized periodically retained their undifferentiated morphology even after 5 days of treatment. 3. The maximal amplitude of high-voltage-activated calcium currents (ICa) increased from the control level of 117.8 +/- 48.3 (mean +/- S.D.) to 387.2 +/- 90.1 pA within 3 days of NGF treatment. omega-Conotoxin (5-10 microM) inhibited 24.6 +/- 8.5% of ICa in undifferentiated cells and 57.8 +/- 6.9% in NGF-treated cells. 4. The levels of c-fos and c-jun mRNAs increased transiently during each daily exposure to NGF. The level of c-fos mRNA also increased transiently during repeated KCl-induced depolarizations but c-jun mRNA remained low or absent. 5. Naive PC12 cells were transiently co-transfected with expression plasmids that contained the full length of c-fos and c-jun cDNA. After 2 days following transfection, the PC12 cells could be grouped according to the size of ICa. In 56% of cells, ICa was similar to control currents (106.1 +/- 37.4 pA). In the remaining 44% of cells, ICa showed a 2.2-fold enhancement with respect to control cells. Transfection of only c-fos had no effect on ICa but, in 24% of cells transfected with c-jun, ICa was 176.6 +/- 124.6 pA. Since periodic membrane depolarization induced c-fos but not c-jun mRNA, c-jun transfection was combined with a high-K+ treatment over 3 days. In 18% of treated cells, ICa was 3.7 times larger than control currents. Morphological differentiation was not observed in transfected cells. 6. In PC12 cells co-transfected with c-fos and c-jun or treated with high K+ after transfection of c-jun, omega-conotoxin (5-10 microM) inhibited 68.7 +/- 11.9% of ICa when the current amplitude was in the range of 200-600 pA. since similar concentrations of omega-conotoxin blocked 19.2 +/- 5.4% of ICa in control cells, the current increase induced by c-fos and c-jun was supported by up to 11-fold enhancement of the omega-conotoxin-sensitive component of ICa.(ABSTRACT TRUNCATED AT 400 WORDS)

Adrenal Gland Neoplasms↗
PubMed1993

Differential expression of immediate early genes after transection of the facial nerve.

Facial motoneurons respond to peripheral transection of the facial nerve with a number of molecular changes. In order to obtain insight into the transcriptional mechanisms underlying the changes induced by axotomy, the expression of a number of immediate early genes was investigated after facial nerve lesion in the rat. Some immediate early genes (such as c-fos, c-jun or jun B) are known to encode transcription factors that bind to DNA at sites that regulate gene expression and they could therefore contribute to long-term changes in motoneurons. Northern blot analysis of RNA extracted from the facial nucleus from postoperative intervals covering hours and days revealed that axotomy results in a unique pattern of immediate early gene induction in the facial nucleus. c-Jun, jun B and 12-O-tetradecanoylphorbol-13-acetate-induced sequence (TIS) 11 messenger RNA, also present in low amounts in the unoperated nucleus, were strongly induced in a long-term fashion after nerve injury. Increased levels of these messenger RNAs were first detectable at 5 h, reaching a maximum (300-500% compared to control) within 24 h followed by a gradual decline during the following week. Elevated levels were maintained at least up to eleven days compared to the unoperated side. On the other hand, c-fos messenger RNA was neither expressed in the unoperated nucleus, nor was c-fos messenger RNA induced by axotomy at any of the time-points studied. Another member of the TIS family of immediate early genes TIS 7 (PC4), however, was detectable at low levels in normal facial nucleus, but its expression was unaffected by lesion. The three axotomy-induced messenger RNAs, c-jun, jun B and TIS 11, were all localized in the facial motoneurons by in situ hybridization histochemistry indicating that their induction occurs as part of the retrograde reaction of the motoneurons in response to lesion. These data suggest that c-jun, jun B and TIS 11 may play a role in triggering the regeneration programme of motoneurons.

Animals↗