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C Kane

Publications and source records attributed to C Kane.

At least 19 recordsLinked to original sources
PubMed2001

Critical roles of a cyclic AMP responsive element and an E-box in regulation of mouse renin gene expression.

Mouse As4.1 cells, obtained after transgene-targeted oncogenesis to induce neoplasia in renal renin expressing cells, express high levels of renin mRNA from their endogenous Ren-1(c) gene. We have previously identified a 242-base pair enhancer (coordinates -2866 to -2625 relative to the CAP site) upstream of the mouse Ren-1(c) gene. This enhancer, in combination with the proximal promoter (-117 to +6), activates transcription nearly 2 orders of magnitude in an orientation independent fashion. To further delimit sequences necessary for transcriptional activation, renin promoter-luciferase reporter gene constructs containing selected regions of the Ren-1(c) enhancer were analyzed after transfection into As4.1 cells. These results demonstrate that several regions are required for full enhancer activity. Sequences from -2699 to -2672, which are critical for the enhancer activity, contain a cyclic AMP responsive element (CRE) and an E-box. Electrophoretic mobility shift assays demonstrated that transcription factors CREB/CREM and USF1/USF2 in As4.1 cell nuclear extracts bind to oligonucleotides containing the Ren-1(c) CRE and E-box, respectively. These two elements are capable of synergistically activating transcription from the Ren-1(c) promoter. Moreover, mutation of either the CRE or E-box results in almost complete loss of enhancer activity, suggesting the critical roles these two elements play in regulating mouse Ren-1(c) gene expression. Although the Ren-1(c) gene contains a CRE, its expression is not induced by cAMP in As4.1 cells. This appears to reflect constitutive activation of protein kinase A in As4.1 cells since treatment with the protein kinase A inhibitor, H-89, caused a significant reduction in Ren-1(c) gene expression and this reduction is mediated through the CRE at -2699 to -2688.

Animals↗
PubMed2001

A comparison of radical retropubic with perineal prostatectomy for localized prostate cancer within the Uniformed Services Urology Research Group.

OBJECTIVE: To review and compare the outcome of patients undergoing radical retropubic prostatectomy (RRP) or radical perineal prostatectomy (RPP) for clinically localized prostate cancer. PATIENTS AND METHODS: From 1988 to 1997, 1382 men who were treated by RRP and 316 by RPP were identified from databases of the Uniformed Services Urology Research Group. The following variables were assessed; age, race, prostate-specific antigen (PSA) level before surgery, clinical stage, biopsy Gleason sum, estimated blood loss (EBL), margin-positive rate, pathological stage, biochemical recurrence rate, short and long-term complication rates, impotence and incontinence rates. To eliminate selection bias, the analysis was concentrated on pairs of patients matched by race, preoperative PSA level, clinical stage and biopsy Gleason sum. RESULTS: In the 190 matched patients there were no significant differences between the RRP and RPP groups in either organ-confined (57% vs 55%), margin-positive (39% vs 43%), or biochemical recurrence rates (12.9% vs 17.6% at a mean follow-up of 47.1 vs 42.9 months), respectively. The mean EBL was 1575 mL in the RRP group and 802 mL in the RPP group (P < 0.001). The only significant difference in complication rates was a higher incidence of rectal injury in the RPP group (4.9%) than in the RRP group (none, P < 0.05). CONCLUSIONS: In similar populations of patients, RPP offers equivalent organ-confined, margin-positive and biochemical recurrence rates to RRP, while causing significantly less blood loss.

Adult↗
PubMed2000

Prostate cancer in men age 50 years or younger: a review of the Department of Defense Center for Prostate Disease Research multicenter prostate cancer database.

PURPOSE: Prostate cancer in men age 50 years or younger traditionally has accounted for approximately 1% of those diagnosed with prostate cancer. Prior studies of prostate cancer in men of this age led many clinicians to believe that they have a less favorable outcome than older men. Most of these studies were conducted before the advent of prostate specific antigen (PSA) screening programs. We evaluated a surgically treated cohort of men age 50 years or younger to determine whether disease recurred more frequently among them than in those 51 to 69 years old in the PSA era. MATERIALS AND METHODS: We reviewed the medical records of 477 men who underwent radical prostatectomy between 1988 and 1997. Age, ethnicity, preoperative PSA, clinical and pathological stage, margin and seminal vesicle involvement, and recurrence were compared between 79 men age 50 years or younger (study group) and 398, 51 to 69 years old (comparison group). Disease-free survival rates were compared using Kaplan-Meier and Cox regression techniques. RESULTS: There were 6 (7.6%) recurrences in the study group (79) and 107 (26.9%) in the comparison group (398). The disease-free survival curves were significantly different (log-rank p = 0.010). Age remained a significant prognostic factor (Wald p = 0.033) in multivariate Cox regression analyses that controlled for race, clinical and pathological stage, and pretreatment PSA. Similar results were found when the comparison group was limited to 116 patients 51 to 59 years old (log-rank p = 0.034, Wald p = 0.069). CONCLUSIONS: These data suggest that patients in the PSA era who underwent radical prostatectomy and were age 50 years or younger have a more favorable disease-free outcome compared to older men.

Adenocarcinoma↗
PubMed2000

Impact of body weight on urinary electrolytes in urinary stone formers.

OBJECTIVES: Obesity increases the risk of developing chronic medical conditions such as diabetes mellitus, hypertension, and coronary artery disease. We performed a retrospective review of a large data base on urinary stones to determine if differences are found in urine and serum chemistries among obese and nonobese stone-forming patients. The effect of body weight on stone recurrence among urinary stone formers was also determined. METHODS: A national data base containing serum biochemical profiles, 24-hour urine specimens, and standardized questionnaires was retrospectively evaluated from 5942 consecutive patients with urinary stone disease. Stone-forming patients were classified by body weight: nonobese men, less than 100 kg and nonobese women, less than 85 kg; intermediate men, 100 to 120 kg and intermediate women, 85 to 100 kg; and obese men, more than 120 kg and obese women, more than 100 kg. RESULTS: Obese stone formers comprised 6.8% (n = 404) of the patient population. The mean weight in the nonobese and obese groups was 81 kg versus 134 kg, respectively, for men and 64 kg versus 112 kg, respectively, for women. Obese patients represented 3.8% of the male and 12.6% of the female population. Obese patients had increased urinary excretion of sodium, calcium, magnesium, citrate, sulfate, phosphate, oxalate, uric acid, and cystine; obesity was associated with increased urinary volumes and urine osmolality compared with the nonobese patients. Obese men had increased concentration of urinary sodium, oxalate, uric acid, sulfate, and phosphate when corrected for urinary volume. Obese women had increased concentrations of sodium, uric acid, sulfate, phosphate, and cystine. The mean number of stone episodes in nonobese versus obese men was similar (3.55 and 3.56), whereas mean stone episodes were 2.93 and 3.38 (P = 0.045) for nonobese versus obese women. CONCLUSIONS: Among known stone formers, obesity is associated with unique changes in both serum and urinary chemistries. These changes are associated with an increased incidence of urinary stone episodes in obese women but not in obese men.

Adolescent↗
PubMed2000

Interleukin-1beta induces complement component C3 and IL-6 production at the basolateral and apical membranes in a human intestinal epithelial cell line.

In previous studies, stimulation of cultured enterocytes with IL-1beta resulted in production of IL-6 and complement component C3. The cellular mechanisms of these responses in the enterocyte are not fully understood. We tested the hypothesis that IL-1beta-induced C3 and IL-6 production is differentially regulated at the apical and basolateral membranes of the enterocyte. Caco-2 cells (a transformed human colonic carcinoma cell line) were grown in a 2-chamber system to full differentiation. The cells were treated with IL-1beta either at the apical or basolateral membrane, and C3 and IL-6 mRNA levels and release of C3 and IL-6 into the apical and basal chambers were determined. The release of C3 was greatest into the basal chamber regardless of whether the cells were stimulated at the apical or basolateral membrane. In contrast, the production of IL-6 was greatest at the cell membrane that was stimulated with IL-1beta. Stimulation of the Caco-2 cells with IL-1beta resulted in increased mRNA levels for C3 and IL-6 with no major differences noted when the cells were treated at the apical or basolateral membrane. The results suggest that enterocyte production and release of at least some acute phase proteins and cytokines are differentially regulated at the apical and basolateral membrane of the enterocyte after stimulation with IL-1beta.

Acute-Phase Reaction↗
PubMed1999

Care provision and community adjustment of rural consumers with serious mental illness.

The purpose of this study was to examine the predictors of successful community living in a sample of rural individuals with severe and persistent mental illness (N = 40). Multimeasure/multisource indicators of consumer status, care provider attitudes, and care provider support provision were employed to predict community adjustment as measured by satisfaction with quality of life. Separate semistructured interviews were conducted with consumers, their case manager, and a family member or adult home provider. Reliability of the measures was established within acceptable limits. The multiple regression analyses showed that life stress and informal care-provider attitudes satisfied the inclusion criteria. R2 was .61 (F[2, 37] = 29.10, p < .001). Quality-of-life satisfaction was predicted primarily by consumer status characteristics.

Adult↗
PubMed1999

Health and self-care practices of persons with schizophrenia.

Data on the self-care and health-related practices and health status of 22 outpatients with schizophrenia were collected from interviews using a series of health survey instruments and a review of patient records. The patients practiced fewer health-promoting behaviors than nonpsychiatric samples described in the literature and were at risk for premature death primarily due to over-eating and smoking. They were most similar to persons with chronic physical illness in their perception of the locus of control of their health. More than half of the patients had physical conditions requiring medical management.

Adult↗
PubMed1998

Characterisation of new efaroxan derivatives for use in purification of imidazoline-binding sites.

The insulin secretagogue activity of certain imidazoline compounds is mediated by a binding site associated with ATP-sensitive K+ (K(ATP)) channels in the pancreatic beta-cell. We describe the effects of a series of structural modifications to efaroxan on its activity at this site. Substitution of amino-, nitro- or azide- groups onto the 5-position of the benzene ring of efaroxan did not significantly affect the functional interaction of the ligand with the islet imidazoline binding site. Modification of the imidazoline ring to an imidazole to generate 2-(2-ethyl-2,3-dihydrobenzo[b]furan-2-yl)-1H-imidazole (KU14R) resulted in loss of secretagogue activity. Indeed, this reagent appeared to act as an imidazoline antagonist since it blocked the secretory responses to imidazoline compounds and also inhibited the blockade of beta-cell K(ATP) channels by efaroxan in patch clamp experiments. Application of KU14R alone resulted in a modest reduction in K(ATP) channel opening, suggesting that it may display weak partial agonism, at least in patch-clamp experiments.

Adenosine Triphosphate↗
PubMed1998

The prevalence of measles antibody in human immunodeficiency virus-infected patients in northern California.

The seroprevalence of measles (rubeola) antibody in 619 human immunodeficiency virus (HIV)-infected adults was determined by a standard ELISA. Risk factors for a lack of antibody and presumed susceptibility to measles were examined. Whereas overall, 9.8% of patients (60) were found to lack antibody, 17.8% of those born within the United States in 1957 or later were antibody-negative. Multivariate analysis showed that absence of measles antibody was significantly associated with younger age (born in 1957 or later) (odds ratio [OR], 8.15; 95% confidence interval [CI], 3.7-21.5; P < .0001) and birth within the United States (OR, 4.72; 95% CI, 1.7-19.7; P = .0045). Neither minority status, stage of HIV infection, CD4 cell count, nor a history of opportunistic infection bore any relationship to the presence of antibody. While progression of HIV disease does not affect measles serostatus, younger HIV-infected patients, especially those born in the United States in 1957 or later, are at the greatest risk for measles.

Adolescent↗
PubMed1997

Therapy for persistent hyperinsulinemic hypoglycemia of infancy. Understanding the responsiveness of beta cells to diazoxide and somatostatin.

The neonatal disorder persistent hyperinsulinemic hypoglycemia of infancy (PHHI) arises as the result of mutations in the subunits that form the ATP-sensitive potassium (KATP) channel in pancreatic beta cells, leading to insulin hypersecretion. Diazoxide (a specific KATP channel agonist in normal beta cells) and somatostatin (octreotide) are the mainstay of medical treatment for the condition. To investigate the mechanism of action of these agents in PHHI beta cells that lack KATP currents, we applied patch clamp techniques to insulin-secreting cells isolated from seven patients with PHHI. Five patients showed favorable responses to medical therapy, and two were refractory. Our data reveal, in drug-responsive patients, that a novel ion channel is modulated by diazoxide and somatostatin, leading to termination of the spontaneous electrical events that underlie insulin hypersecretion. The drug-resistant patients, both of whom carried a mutation in one of the genes that encode KATP channel subunits, also lacked this novel K+ channel. There were no effects of diazoxide and somatostatin on beta cell function in vitro. These findings elucidate for the first time the mechanisms of action of diazoxide and somatostatin in infants with PHHI in whom KATP channels are absent, and provide a rationale for development of new therapeutic opportunities by K+ channel manipulation in PHHI treatment.

Blood Glucose↗
PubMed1997

Verapamil, a phenylalkylamine Ca2+ channel blocker, inhibits ATP-sensitive K+ channels in insulin-secreting cells from rats.

Radioisotopic and electrophysiological techniques were used to assess the effects of verapamil, a phenylalkylamine Ca2+ channel blocker, on K+ permeability of insulin-secreting cells. Verapamil provoked a concentration-dependent inhibition of 86Rb (42K substitute) outflow from prelabelled and perifused rat pancreatic islets. This property appears to be inherent to the phenylalkylamine Ca2+ channel blockers since gallopamil, a methoxyderivative of verapamil, but not nifedipine, a 1,4-dihydropyridine Ca2+ channel blocker, inhibited 86Rb outflow. The experimental data further revealed that verapamil interacted with a Ca2+-independent, glucose- and glibenclamide-sensitive modality of 86Rb extrusion. Moreover, verapamil prevented the increase in 86Rb outflow brought about by BPDZ 44; a potent activator of the ATP-sensitive K+ channel. Single-channel current recordings by the patch clamp technique confirmed that verapamil elicited a dose-dependent inhibition of the ATP-dependent K+ channel. Lastly, under experimental conditions in which verapamil clearly inhibited the ATP-sensitive K+ channels, the drug did not affect 45Ca outflow, the cytosolic free Ca2+ concentration or insulin release. It is concluded that the Ca2+ entry blocker verapamil inhibits ATP-sensitive K+ channels in pancreatic beta cells. This effect was not associated with stimulation of insulin release.

Adenosine Triphosphate↗
PubMed1997

Characterization of ion channels in stimulus-secretion coupling in pancreatic islets.

The regulation of insulin secretion from beta-cells of the pancreatic islets of Langerhans is a highly integrated process involving several plasma membrane ion channels. The key to our understanding of the normal process is the hypothesis that glucose-induced closure of K+ channels leads to a depolarization of the cell membrane potential and the opening of voltage-gated Ca2+ channels. Support for this is provided by direct electrophysiological recordings of ion channel activity, and by recent data that have revealed how gene defects in ion channel subunits leads to the loss of regulated insulin secretion. Here, we review the general features of stimulus-response coupling in beta-cells, and how novel initiatives are providing key insights into beta-cell pathogenesis.

Adenosine Triphosphate↗
PubMed1997

Travels with HIV: the compliance and health of HIV-infected adults who travel.

We examined the effects of travel on the health of a group of HIV-infected adults (n = 89) cared for in a public hospital HIV clinic. In a period of 2 years, 45% travelled to a median of 3 US destinations for at least one week and 20% travelled to at least one international destination for a mean duration of 20 days. At the time of completion of the survey, the majority of these patients were severely immunosuppressed (median CD4+ count, 120/mm3). A physician was consulted concerning travel before 53% of the trips, but only one person consulted a travel medicine expert. All but one patient (98%) who was receiving medical therapy carried sufficient supplies of medication; 95% estimated their compliance with medication at 75% or better. None of the travellers to developing countries received gamma globulin, but one received yellow fever vaccine. Fifteen travellers (43%) became ill either during their trip or immediately thereafter; 3 required hospitalization. While most illnesses were not severe, 4 patients developed potentially life-threatening infections including coccidioidomycosis, cryptococcosis, PCP, and bacterial pneumonia. This survey provides information by which the clinician can anticipate the health care needs of HIV-infected patients who travel. HIV-infected patients should be more aware of the necessity for medical counsel prior to travel.

AIDS-Related Opportunistic Infections↗
PubMed1996

Role of proximal promoter elements in regulation of renin gene transcription.

Mouse As4.1 cells, obtained after transgene-targeted oncogenesis to induce neoplasia in renal renin-expressing cells, express high levels of renin mRNA from the endogenous Ren-1(c) gene. We have used these cells to characterize the role of the Ren-1(c) proximal promoter (+6 to -117) in the regulation of renin gene transcription. It was found that 4.1 kilobases (kb) of Ren-1(c) 5'-flanking sequence, in combination with the proximal promoter, are required for strong activation (approximately 2 orders of magnitude over the basal level of the promoter alone) of the chloramphenicol acetyltransferase reporter in transfection assays. Within the 4.1-kb fragment, a 241-base pair region was identified that retains full activity in an orientation-independent manner in combination with the promoter. The resulting transcripts initiate at the normal renin start site. Electrophoretic mobility shift assays identified a sequence at approximately position -60 in the promoter region that binds nuclear proteins specific for renin-expressing As4.1 cells. Mutations in this sequence, which disrupt binding of nuclear protein(s), completely abolish activation of transcription by the 4. 1-kb fragment. Activation of transcription by the 241-base pair enhancer was still observed, although it was diminished in magnitude (60-fold over the mutated promoter alone). We present a model derived from the current data that suggests that regulation of renin expression is achieved through cooperation of transcription factors binding at the proximal promoter element and a distal enhancer element to abrogate or override the effects of an intervening negative regulatory region.

Animals↗
PubMed1996

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Cost-Benefit Analysis↗
PubMed1996

Sequential granulocyte colony-stimulating factor increases cisplatin cytotoxicity in human epithelial ovarian cancer cell lines.

BACKGROUND: To determine the effect of granulocyte colony-stimulating factor (G-CSF) on tumor growth and cisplatin cytotoxicity in human epithelial ovarian cancer. METHODS: Six human epithelial ovarian cancer cell lines were treated with media (control) for 24 hr, G-CSF for 24 hr, cisplatin for 24 hr, simultaneous cisplatin and G-CSF for 24 hr, media (control) for 48 hr, cisplatin for 24 hr and sequential media for 24 hr, cisplatin for 24 hr, and sequential G-CSF for 24 hr. Following incubation, the percentage cell lysis was determined by particle concentration fluorescein immunoassay chemosensitivity assay. RESULTS: G-CSF resulted in tumor cell growth (7-19%) in three cell lines. Simultaneous G-CSF decreased cisplatin cytotoxicity in five cell lines (7-45%). Sequential G-CSF increased cisplatin cytotoxicity in all six cell lines (5-108%). CONCLUSIONS: G-CSF may result in ovarian cancer proliferation. Simultaneous G-CSF may decrease cisplatin cytotoxicity, while sequential G-CSF appears to increase cisplatin cytotoxicity.

Cell Division↗