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J Rice

Publications and source records attributed to J Rice.

At least 55 records · Page 3Linked to original sources
PubMed1999

Mechanisms of altered excitation-contraction coupling in canine tachycardia-induced heart failure, II: model studies.

Ca2+ transients measured in failing human ventricular myocytes exhibit reduced amplitude, slowed relaxation, and blunted frequency dependence. In the companion article (O'Rourke B, Kass DA, Tomaselli GF, Kääb S, Tunin R, Marbán E. Mechanisms of altered excitation-contraction coupling in canine tachycardia-induced heart, I: experimental studies. Circ Res. 1999;84:562-570), O'Rourke et al show that Ca2+ transients recorded in myocytes isolated from canine hearts subjected to the tachycardia pacing protocol exhibit similar responses. Analyses of protein levels in these failing hearts reveal that both SR Ca2+ ATPase and phospholamban are decreased on average by 28% and that Na+/Ca2+ exchanger (NCX) protein is increased on average by 104%. In this article, we present a model of the canine midmyocardial ventricular action potential and Ca2+ transient. The model is used to estimate the degree of functional upregulation and downregulation of NCX and SR Ca2+ ATPase in heart failure using data obtained from 2 different experimental protocols. Model estimates of average SR Ca2+ ATPase functional downregulation obtained using these experimental protocols are 49% and 62%. Model estimates of average NCX functional upregulation range are 38% and 75%. Simulation of voltage-clamp Ca2+ transients indicates that such changes are sufficient to account for the reduced amplitude, altered shape, and slowed relaxation of Ca2+ transients in the failing canine heart. Model analyses also suggest that altered expression of Ca2+ handling proteins plays a significant role in prolongation of action potential duration in failing canine myocytes.

Action Potentials↗
PubMed1999

Description of the Genetic Analysis Workshop 11 Collaborative Study on the Genetics of Alcoholism.

Problem 1 of Genetic Analysis Workshop 11 consists of data from a family study of the genetics of alcoholism and related traits contributed by the six centers making up the National Institute for Alcohol Abuse and Alcoholism sponsored by the Collaborative Study on the Genetics of Alcoholism (COGA). The family data included 1,214 members of 105 pedigrees ascertained for having three or more individuals affected with alcoholism. Data available to workshop participants included clinical phenotypes, personality measures, smoking behavior, event-related potentials, platelet monamine oxidase B activity, and a genome scan of 296 markers.

Alcoholism↗
PubMed1999

Structural decomposition of genetic diversity in families with alcoholism.

Using genotypes of 280 marker loci on the 22 autosomes of 105 alcohol-dependent probands, their affected and unaffected sibs, as well as their parents, we iteratively constructed a genetic similarity function that enabled us to quantify the interindividual genetic distances d(x(i), xj) between feature vectors x(i), xj made up by the allelic patterns of individuals i, j with respect to loci l1, l2,...,ln. Based on this similarity function, we investigated the sib-sib similarities that are expected to deviate from "0.5" in affected sib pairs if the region of interest contains markers close to disease-causing genes. The reference value "0.5" was derived from the parents-offspring similarities, because these are independent of the affection status. The question of population admixture was addressed by means of multivariate structural analyses. These analyses led to four "natural" groups whose validity was tested through the father-mother similarities. Additionally, we determined the eigenvectors that optimally represented the genetic variation and found several marker configurations on chromosomes 1, 3, 7, 15, and 17 that reproducibly discriminated (p < or = 0.01) affected probands/sibs from unaffected sibs, while no such differences were found between affected probands and affected sibs.

Alcoholism↗
PubMed1999

The unstable distal radial fracture one year post Kapandji intrafocal pinning.

Kapandji pinning has been proposed as the treatment of choice for unstable Colles' fractures. The aim of this paper is to evaluate our experience treating unstable Colles' type fractures using this technique. Over a nine month period, 36 patients with Colles' type fractures were treated operatively at St. Vincent's Hospital. 22 of these fractures were deemed unstable and were treated using percutaneous intrafocal Kapandji pinning. 20 of these patients were recalled for review at a mean of 11.3 month post injury. At this stage the wrist was examined clinically and radiologically. Initial satisfactory correction of deformity was achieved by this technique. Between the time of wire removal and final review, however, there was significant recurrence of dorsal angulation (P < 0.05), but no significant radial shortening on radiographs. The patients had a satisfactory clinical result in spite of these radiological parameters.

Adult↗
PubMed1999

Networks of persons with syphilis and at risk for syphilis in Louisiana: evidence of core transmitters.

BACKGROUND AND OBJECTIVES: Differences in sociodemographic attributes and healthcare access may explain differences in regional sexually transmitted disease rates but don't fully explain why syphilis persists disproportionately in certain populations. GOAL OF THIS STUDY: To understand the behavioral epidemiology of syphilis, we conducted a social network analysis of persons with syphilis and their contacts and developed and applied a definition of core transmitters. STUDY DESIGN: We interviewed 10 index persons with primary or secondary untreated syphilis and 80 of their named sexual and social contacts. RESULTS: Fourteen (16%) of 90 interviewed persons met the definition of core transmitters, 9 of whom had past or current syphilis. The other interviewed persons had only moderately risky behaviors. Seventy-eight (42%) of the network sexual contacts were connected directly or indirectly to a core transmitter. CONCLUSION: This analysis suggests that syphilis transmission is maintained by a community with a small percentage of high-risk persons centrally placed amidst a larger group with moderately risky behavior.

Adult↗
PubMed1999

Long-term outpatient dalteparin (fragmin) therapy for arterial and venous thrombosis: efficacy and safety--a preliminary report.

The availability of low molecular weight heparin (LMWH), with associated ease of home delivery and enhanced efficacy and safety, has rendered the long-term outpatient use of LMWH feasible. Although warfarin is usually used for long-term secondary prevention, it is not the drug of choice for a variety of conditions such as antiphospholipid thrombosis syndrome, sticky platelet syndrome, and patients with malignancy and other medical conditions who have failed adequate warfarin doses. We assessed the long-term efficacy and safety of outpatient dalteparin in a series of patients with conditions associated with prior warfarin failure or potential to warfarin therapy (antiphospholipid syndrome). The results of this study, detailed herein, demonstrate that long-term dalteparin is highly effective and safe when used as long-term therapy for secondary prevention in selected prothrombotic disorders.

Adult↗
PubMed1999

Implementation of condom social marketing in Louisiana, 1993 to 1996.

OBJECTIVES: This article describes the implementation and impact of the first statewide condom social marketing intervention in the United States. METHODS: A statewide social marketing program made condoms freely available in 93 public health clinics, 39 community mental health centers, 29 substance abuse treatment sites, and more than 1000 businesses in neighborhoods with high rates of sexually transmitted diseases (STDs) and HIV. Surveys about condom use were conducted annually. RESULTS: Between 1994 and 1996, more than 33 million condoms were distributed without significant opposition. Over time, self-reported condom use at the last sexual encounter increased among African American women (from 28% in 1994 to 36% in 1996), particularly African American women with 2 or more sex partners (from 30% to 48%). Condom use at the last sexual encounter increased among African American men (from 40% in 1994 to an average of 54% in 1996). The number of reported sex partners did not increase. CONCLUSIONS: Condom social marketing can be successfully implemented in the United States. The widespread availability of free condoms is associated with increased condom use, particularly among persons at high risk for STDs and HIV.

Adolescent↗
PubMed1999

DNA vaccines against haematological malignancies.

DNA vaccines against cancer have to activate an inadequate or damaged immune system in order to attack residual cancer cells. Although the potential problem of tolerance may be overcome by transplantation, provision of high levels of T-cell help is likely to be an important factor in stimulating effective immune pathways. The fusion gene approach appears to provide the required help, and offers a rational design for raising both antibody and T-cell mediated attack against lymphoma and myeloma, which express idiotypic antigen at the cell surface or as a secreted protein respectively. Intriguingly, preliminary data indicate that the fusion gene approach promotes antibody responses against a different cell surface tumour antigen, CEA. Strategies for using DNA vaccines to induce attack on processed peptides bound to MHC class I molecules are also being developed. We hope and anticipate that all categories of tumour antigen may be susceptible to this powerful new technology. The critical clinical requirement, however, will be to treat the presenting tumour with maintenance or restoration of immune capacity. We await results of the preliminary clinical trials with great interest.

Animals↗
PubMed1998

Mammography use helps to explain differences in breast cancer stage at diagnosis between older black and white women.

BACKGROUND: Older black women are less likely to undergo mammography and are more often given a diagnosis of advanced-stage breast cancer than older white women. OBJECTIVE: To investigate the extent to which previous mammography explains observed differences in cancer stage at diagnosis between older black and white women with breast cancer. DESIGN: Retrospective cohort study using the Linked Medicare-Tumor Registry Database. SETTING: Population-based data from three geographic areas of the United States included in the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program (Connecticut; metropolitan Atlanta, Georgia; and Seattle-Puget Sound, Washington). PARTICIPANTS: Black and white women 67 years of age and older in whom breast cancer was diagnosed between 1987 and 1989. MEASUREMENTS: Medicare claims were used to classify women according to mammography use in the 2 years before diagnosis as nonusers (no previous mammography), regular users (> or =2 mammographies done at least 10 months apart), or peri-diagnosis users (mammography done only within 3 months before diagnosis). Information on mammography use was linked with SEER data to determine cancer stage at diagnosis. Stage was classified as early (in situ or local) or late (regional or distant). RESULTS: Black women were more likely to not undergo mammography (odds ratio [OR], 3.00 [95% CI, 2.41 to 3.75]) and to be given a diagnosis of late-stage disease (OR, 2.49 [CI, 1.59 to 3.92]) than white women. When women were stratified by previous mammography use, the black-white difference in cancer stage occurred only among nonusers (adjusted OR, 2.54 [CI, 1.37 to 4.71]). Among regular users, cancer was diagnosed in black and white women at similar stages (adjusted OR, 1.34 [CI, 0.40 to 4.51]). In logistic modeling, previous mammography alone explained about 30% of the excess late-stage disease in black women. In a separate model, previous mammography explained 12% of the excess late-stage disease among black women after adjustment for sociodemographic and comorbidity information. CONCLUSION: Differences in breast cancer stage at diagnosis between older black and white women are related to previous mammography use. Increased regular use of mammography may result in a shift toward earlier-stage disease at diagnosis and narrow the observed differences in stage at diagnosis between older black and white women.

Black or African American↗
PubMed1998

Pregnancy is not associated with the progression of HIV disease in women attending an HIV outpatient program.

The objective of this study was to determine whether pregnancy is associated with an acceleration of human immunodeficiency virus (HIV) disease progression in women who have a pregnancy while HIV infected. A retrospective review of all women aged 15-35 years who attended an HIV outpatient program from January 1989 through August 1995, was undertaken. The 192 women who had a term pregnancy after testing positive for HIV were compared with 164 women who were not pregnant during the same period. The main outcome measures were death, the occurrence of a first acquired immunodeficiency syndrome (AIDS)-defining condition, or a condition indicative of symptomatic HIV. Disease progression was assessed using the Kaplan-Meier method and multivariate proportional hazards models. Compared with nonpregnant women, women with a term pregnancy were significantly more likely to be African-American (88% vs. 78%, p < 0.05), younger than 22 years of age (51 % vs. 11%, p < 0.001), and to have entered the clinic with a higher median CD4 count (519 vs. 433 cells/microl, p < 0.001). After adjusting for entry CD4 count and other factors, pregnancy was not associated with progression to any of the study outcomes. Thus, in women attending a publicly funded clinic, pregnancy does not appear to accelerate the progression of HIV disease.

Acquired Immunodeficiency Syndrome↗
PubMed1998

Durable remission of locally advanced breast cancer with multimodality management.

We treated 20 women with locally advanced breast cancer between January 1991 and September 1996. The treatment regimen included 4 cycles of intensive doxorubicin (30 mg/m2/d on 3 consecutive days every 2 weeks with G-CSF support), followed by appropriate surgery, followed by high dose therapy with cyclophosphamide, carboplatin and thiotepa (STAMP V, CTCb). Of the 20 patients, seven presented with inflammatory breast cancer, three with Stage IIIB, seven with stage IIIA, one with multifocal Stage IIB and two with Stage IV M1 (ipsilateral supraclavicular lymph node involvement) (including one who had an inflammatory primary) disease. Six patients had not undergone mastectomy at the time of entering the protocol. These six received the doxorubicin in a neoadjuvant fashion and were thus evaluable for tumor response. The remaining 14 received doxorubicin as adjuvant therapy prior to intensification and transplantation. All patients underwent local-regional radiation therapy and were placed on oral tamoxifen. Doxorubicin was well tolerated in this schedule with all but three patients receiving all their cycles on schedule. Both BM and PBPC were easily collected after this regimen and, when reinfused, resulted in the prompt recovery of granulocytes (median 11 days to 500 absolute granulocyte count) and platelets (median 13 days to 20,000 platelets). The six patients who received doxorubicin prior to mastectomy all had major clinical responses, but were found to have microscopic focii of breast cancer in the mastectomy specimens. The overall treatment was well tolerated with the exception of one treatment-related death (5%). The overall and relapse free survival are 70% and 58% respectively with a median follow-up of 40 months (range 12-74 months). When the Stage IV patients are censored, the relapse-free survival rate is 69%. In the bone marrow transplant phase of treatment, the major non-hematologic toxicities were stomatitis (70%) and anorexia requiring parental nutrition (75%).

Adult↗
PubMed1998

Femoral cementing techniques in total hip replacement.

Clinical studies have shown that second-generation femoral cementing techniques at total hip replacement result in a superior fixation of the femoral stem. In an effort to determine what benefits further developments in cementing techniques would provide, we compared the morphology of the cement mantles produced by traditional finger-packing and gun-insertion techniques. The porosity of the cement mantles was quantified using computerised image analysis. The finger-packing technique caused large air inclusions that resulted in large pores in the substance of the cement mantle, whereas the cement-gun technique did not result in any individual pore with an equivalent diameter greater than 3 mm. The mean porosity of cement mantles prepared using the finger-insertion technique was 8.3%, whereas the mean porosity in gun-prepared mantles was 1.7%. The use of a cement gun significantly reduced the porosity of femoral cement mantles (P = 0.02). Reduction of defects in the substance of the cement mantle may account for the increased survival of femoral prostheses inserted when second-generation techniques were used. Further reduction of the porosity of the cement mantle could not be expected to produce as dramatic a clinical improvement in prosthesis fixation.

Arthroplasty, Replacement, Hip↗
PubMed1998

Modeling the cellular basis of altered excitation-contraction coupling in heart failure.

Ca transients measured in failing human ventricular myocytes exhibit reduced amplitude and slowed relaxation [Beuckelmann, D.J., Nabauer, M., Erdmann, E., 1992. Intracellular calcium handling in isolated ventricular myocytes from patients with terminal heart failure. Circulation 85, 1046-1055; Gwathmey, J.K., Copelas, L., MacKinnon, R., Schoen, F.J., Feldman, M.D., Grossman, W., Morgan, J.P., 1987. Abnormal intracellular calcium handling in myocardium from patients with end-stage heart failure. Circ. Res. 61, 70-76; Kaab, S., Nuss, H. B., Chiamvimonvat, N., O'Rourke, B., Pak, P.H., Kass, D.A., Marban, E., Tomaselli, G.F., 1996. Ionic mechanism of action potential prolongation in ventricular myocytes from dogs with pacing-induced heart failure. Circ. Res. 78(2); Li, H.G., Jones, D.L., Yee, R., Klein, G.J., 1992. Electrophysiologic substrate associated with pacing-induced hert failure in dogs: potential value of programmed stimulation in predicting sudden death. J. Am. Coll. Cardiol. 19(2), 444-449; Vermeulen, J.T., McGuire, M.A., Opthof, T., Colonel, R., Bakker, J.M.T.d., Klopping, C., Janse, M.J., 1994. Triggered activity and automaticity in ventricular trabeculae of failing human and rabbit hearts. Cardiovasc. Res. 28, 1547-1554.] and blunted frequency dependence [Davies, C.H., Davia, K., Bennett, J.G., Pepper, J.R., Poole-Wilson, P.A., Harding, S.E., 1995. Reduced contraction and altered frequency response of isolated ventricular myocytes from patients with heart failure. Circulation, 92, 2540-2549; Hasenfuss, G., Reinecke, H., Studer, R., Meyer, M., Pieske, B., Holtz, J., Holubarsch, C., Posival, H., Just, H., Drexler, H., 1994. Relation between myocardial function and expression of sarcoplasmic reticulum Ca-ATPase in failing and nonfailing human myocardium. Circ. Res. 75, 434-442; Hasenfuss, G., Reinecke, H., Studer, R., Pieske, B., Meyer, M., Drexler, H., Just, H., 1996. Calcium cycling proteins and force-frequency relationships in heart failure. Basic Res. Cardiol. 91, 17-22; Monte, F.D., O'Gara, P., Poole-Wilson, P.A., Yacoub, M., Harding, S.E., 1995. Cell geometry and contractile abnormalities of myocytes from failing human left ventricle.

Action Potentials↗
PubMed1998

Failure to demonstrate parent-of-origin effect in transmission of bipolar II disorder.

BACKGROUND: Parent-of-origin effect (POE) is suggested in transmission of bipolar disorder. Bipolar II disorder (BPII) should be considered separately. METHODS: The gender difference of transmitting parents, prevalence rate in children, and age at onset of patients in relation to the sex of the transmitting parent, were examined in 220 BPII patients. RESULTS: No evidence suggesting involvement of POE was found. CONCLUSION: POE is not involved in transmission of BPII. LIMITATION: Number of subjects is not sufficient. Rate of interviewed subjects differs between mothers and fathers. CLINICAL RELEVANCE: Female BPII patients do not transmit the disease more often than male patients.

Adult↗
PubMed1998

Interprosthetic fracture of the femoral shaft.

Experience in the management of a complication of ipsilateral hip and knee arthroplasty is described. The cases of four female patients who sustained a femoral shaft fracture after ipsilateral hip and knee arthroplasty are reported. All fractures were treated operatively, and in all cases internal fixation devices failed. This complication of multiple joint arthroplasty presents a difficult management problem. Rigid fixation has a high failure rate for this type of fracture. Surface knee arthroplasty provides a better opportunity for internal fixation than a knee arthroplasty with a stemmed femoral component.

Aged↗
PubMed1998

DNA vaccines with single-chain Fv fused to fragment C of tetanus toxin induce protective immunity against lymphoma and myeloma.

Vaccination with idiotypic protein protects against B-cell lymphoma, mainly through anti-idiotypic antibody. For use in patients, DNA vaccines containing single-chain Fv derived from tumor provide a convenient alternative vaccine delivery system. However, single-chain Fv sequence alone induces low anti-idiotypic response and poor protection against lymphoma. Fusion of the gene encoding fragment C of tetanus toxin to single-chain Fv substantially promotes the anti-idiotypic response and induces strong protection against B-cell lymphoma. The same fusion design also induces protective immunity against a surface Ig-negative myeloma. These findings indicate that fusion to a pathogen sequence allows a tumor antigen to engage diverse immune mechanisms that suppress growth. This fusion design has the added advantage of overcoming potential tolerance to tumor that may exist in patients.

Animals↗
PubMed1998

Hematologic abnormalities associated with influenza A infection: a report of 3 cases.

Influenza A is associated with leukopenia, although it is not reported to cause isolated thrombocytopenia, anemia, or pancytopenia. The authors report three pediatric patients with transient cytopenias associated with influenza A infection, all of whom had evidence for influenza A infection by direct immunofluorescence from nasopharyngeal aspirates. In all patients, cytopenias were transient and improved as their viral symptoms resolved. All patients improved spontaneously. This is the first report of transient pancytopenia, anemia, or thrombocytopenia associated with influenza A infection. Given the high frequency of influenza A infections during the winter months, it is important to recognize the associated hematologic findings.

Anemia↗