Biomedical subjects

T Rogers

Publications and source records attributed to T Rogers.

At least 19 recordsLinked to original sources

PubMed2006

The performance of three serum creatinine-based formulas in estimating GFR in former kidney donors.

Studies addressing long-term consequences of living with one kidney have used serum creatinine-based formulas that have not been validated in former kidney donors. Therefore, we evaluated the performance of Cockcroft-Gault (CG), Modification of Diet in Renal Disease (MDRD) and Mayo Clinic formulas in predicting iohexol glomerular filtration rate (iGFR) after donation in 112 randomly selected former kidney donors. Mean time from donation was 12.2 +/- 8.5 years. Serum creatinine was 1.1 +/- 0.2 mg/dL and iohexol GFR was 72 +/- 12 mL/min/1.73 m(2). The majority, 83.9%, of donors had a GFR >60 mL/min. CG formula overestimated GFR by 3.35 +/- 13.6 mL/min and was within 10% of iohexol GFR in only 43.7% of cases. MDRD formula underestimated iohexol GFR by 6.45 +/- 9.5 mL/min and was within 10% of actual GFR in half of the cases. In contrast, the Mayo Clinic equation was the most biased at 14.71 +/- 12.3 mL/min and was within 10% of measured GFR in only a fifth of the cases. Only MDRD and CG formulas provide estimates of GFR in former kidney donors that are within a clinically acceptable range of actual GFR. In conclusion, the majority of former kidney donors have excellent kidney function and the MDRD formula should be the recommended GFR estimating model in this population.

Biomarkers↗

PubMed2005

Economic evaluation of voriconazole compared with conventional amphotericin B for the primary treatment of aspergillosis in immunocompromised patients.

OBJECTIVE: The objective of this study was to conduct an economic evaluation of voriconazole compared with conventional amphotericin B deoxycholate (CAB) using data from a recently reported randomized comparative trial in patients with various underlying immunosuppressive conditions. This trial demonstrated the superiority of voriconazole in terms of clinical response, survival and safety when used as primary therapy for invasive aspergillosis. METHODS: A decision analytic model was designed using an expert panel and populated primarily with efficacy and resource utilization data collected prospectively during the clinical trial. The analysis was carried out from the perspective of the health care system and all costs are reported in 2002 US dollars. RESULTS: Average total treatment costs per patient were 10% lower in the voriconazole arm ($30 664) than in the CAB arm ($34 144), resulting from reduced consumption of hospital resources and fewer changes in antifungal therapy. In the base case analysis, voriconazole provided an average saving of $3481 per treated patient, resulted in a lower cost per survivor ($43 310 versus $58 971) and a lower cost per successfully treated patient ($58 100 versus $108 124) compared with CAB. Sensitivity analyses demonstrated that the cost savings observed were maintained over a wide range of alternative values for both unit costs and resource utilization, including length of hospital stay, time spent in intensive care units, bed day costs and the cost of lipid formulations of amphotericin B. CONCLUSION: Incremental cost-effectiveness analysis indicated the dominance of voriconazole because of both lower costs and greater efficacy.

Amphotericin B↗

PubMed2004

Combination therapy for the treatment of hepatitis C in the veteran population: higher than expected rates of therapy discontinuation.

AIM: To compare the efficacy of high-dose induction with standard dose interferon therapy for the treatment of chronic hepatitis C virus at the Dallas Veterans Affairs Medical Center. METHODS: Patients were randomized to receive 5 million units daily interferon-alpha2b for 4-weeks followed by 44-weeks for genotype 1 or 20 weeks for non-genotype 1 of standard dose therapy (3 million units three times a week) or standard dose therapy for total treatment duration. Daily weight-based ribavirin was used for entire therapy interval. RESULTS: Forty-five patients were enrolled in the trial with genotype 1 comprising 75.6% of the sample. Cirrhosis or bridging-fibrosis was present in 69% of the patients. Of the 29 liver biopsies available for Knodell scoring, 41% and 51% had scores of 6-10 and 11-15, respectively. Rates of sustained virological response did not differ significantly between the two treatment groups. Therapy type and/or early intervention for depression did not affect the rate of therapy discontinuation, which was 26.6%. CONCLUSION: The rate of sustained virological response was similar between the two treatment groups and higher than anticipated among patients with cirrhosis or bridging-fibrosis. The rate of therapy discontinuation was also higher than anticipated but was not attributable to therapy type or untreated depression.

Adult↗

PubMed2004

Influence of biological and ecological factors on hematological values in wild Little Penguins, Eudyptula minor.

Clinical hematology and biochemistry are recognized as useful aids in health diagnosis in birds. The Little Penguin (Eudyptula minor) is endemic to Australia and numbers are declining due to a number of factors including declining health. This 2-year study on both Bowen and Lion Island populations aimed at assessing the potential causes of their declining health. Blood was collected from a total of 294 adult Little Penguins. R.B.C., Hb, P.C.V., M.C.V., M.C.H., M.C.H.C., W.B.C. and differential counts, thrombocytes and T.P.P. were measured. Multiple regression was used to identify relationships between hematological values and the following predictor variables: site, season, sex, time held prior to sampling and body condition. Values obtained showed some differences compared to the values for other penguin species reported in the literature. P.C.V., R.B.C., Hb, M.C.H.C. and T.P.P. showed major differences in comparison with a previous study on little penguins. Considering the influence of predictor variables, it appeared that: P.C.V., R.B.C., M.C.V., M.C.H., M.C.H.C. varied according to seasons; P.C.V., R.B.C., M.C.H., T.P.P. were correlated to body condition; P.C.V. was higher in birds on Bowen Island compared to birds on Lion Island; and T.P.P. was higher in females. These ecological and biological predictor variables have a strong influence upon hematological values. As a consequence, they must be taken into consideration when interpreting results of future studies.

Animals↗

PubMed2004

Quality control limits for voriconazole disk susceptibility tests on Mueller-Hinton agar with glucose and methylene blue.

An international collaborative study was performed in order to propose quality control limits for voriconazole disk diffusion tests on Mueller-Hinton agar with 2% glucose and 0.5 micro g of methylene blue per ml. The supplement may be added to the agar before autoclaving, or Mueller-Hinton agar plates may be flooded with a glucose-methylene blue solution. Replicate tests on both types of agar plates with 1- micro g voriconazole disks generated data to propose zone size limits for tests of Candida parapsilosis ATCC 22019 (28 to 37 mm), Candida albicans ATCC 90028 (31 to 42 mm), and Candida krusei ATCC 6258 (16 to 25 mm). Candida tropicalis ATCC 750 was not useful for this purpose.

Agar↗

PubMed2003

Quality control limits for fluconazole disk susceptibility tests on Mueller-Hinton agar with glucose and methylene blue.

An international collaborative study was performed in order to propose quality control limits for fluconazole disk diffusion susceptibility tests on Mueller-Hinton agar with 2% glucose and 0.5 micro g of methylene blue per ml. The supplements may be added before autoclaving the agar, or Mueller-Hinton agar plates may be flooded with a glucose-methylene blue solution. Replicate tests on both types of agar plates generated data to propose zone size limits for tests of Candida parapsilosis ATCC 22019 (22 to 33 mm), C. tropicalis ATCC 750 (26 to 37 mm), and C. albicans ATCC 90028 (28 to 39 mm). C. krusei ATCC 6258 was not useful for this purpose.

Agar↗

PubMed2001

Hereditary motor and sensory neuropathy-russe: new autosomal recessive neuropathy in Balkan Gypsies.

A novel peripheral neuropathy of autosomal recessive inheritance has been identified in Balkan Gypsies and termed hereditary motor and sensory neuropathy-Russe (HMSN-R). We investigated 21 affected individuals from 10 families. Distal lower limb weakness began between the ages of 8 and 16 years, upper limb involvement beginning between 10 and 43 years, with an average of 22 years. This progressive disorder led to severe weakness of the lower limbs, generalized in the oldest subject (aged 57 years), and marked distal upper limb weakness. Prominent distal sensory loss involved all modalities, resulting in neuropathic joint degeneration in two instances. All patients showed foot deformity, and most showed hand deformity. Motor nerve conduction velocity was moderately reduced in the upper limbs but unobtainable in the legs. Sensory nerve action potentials were absent. There was loss of larger myelinated nerve fibers and profuse regenerative activity in the sural nerve. HMSN-R is a new form of autosomal recessive inherited HMSN caused by a single founder mutation in a 1 Mb interval on chromosome 10q.

Adolescent↗

PubMed2001

Cognitive-behavioral therapy with gay, lesbian, and bisexual clients.

Cognitive-behavioral therapy (CBT) can be adapted to a wide range of clinical difficulties and presenting problems that face lesbians, gay men, and bisexual persons. The following article presents general guidelines for and two case examples of the use of CBT. The first case is a gay male struggling with social phobia. This case is an example of how to adapt a structured, empirically supported cognitive-behavioral treatment focusing on social phobia to situations that are associated with his sexual orientation. The second is a woman struggling with multiple issues including coming out. This case provides an example of how to add specific cognitive-behavioral techniques to coming-out issues within the context of a more eclectic, longer-term therapy.

Adult↗

PubMed2001

Gentamicin causes endocytosis of Na/Pi cotransporter protein (NaPi-2).

BACKGROUND: Renal toxicity is a major side-effect of aminoglycoside antibiotics and is characterized by an early impairment in proximal tubular function. In a previous study, we have shown that gentamicin administration to the rat causes an early impairment in sodium gradient-dependent phosphate (Na/Pi) cotransport activity. The purpose of our current study was to determine the molecular mechanisms of the impairment in Na/Pi cotransport activity, specifically the role of the proximal tubular type II Na/Pi cotransporter. METHODS: Rats were treated for one, two, and three days with two daily injections of 30 mg/kg body weight gentamicin or the vehicle. RESULTS: Gentamicin caused a progressive decrease in superficial cortical apical brush-border membrane (SC-BBM) Na/Pi cotransporter activity (856 +/- 93 in control vs. 545 +/- 87 pmol/mg BBM protein in 3-day gentamicin, P < 0.01). Western blot analysis showed a parallel and progressive decrease in SC-BBM Na/Pi cotransporter protein abundance, a 50% decrease after one day of treatment, a 63% decrease after two days of treatment, and an 83% decrease after three days treatment with gentamicin. In contrast, gentamicin treatment had no effect on Na/Pi cotransport activity or Na/Pi cotransporter protein abundance in BBM isolated from the juxtamedullary cortex (JMC-BBM). Immunofluorescence microscopy showed a major decrease in the expression of Na/Pi cotransporter protein in the apical membrane of the proximal convoluted tubule, with progressive intracellular accumulation of Na/Pi protein. Colocalization studies showed that in gentamicin-treated rats, Na/Pi protein was colocalized in the early endosomes and especially in the lysosomes. Northern blot analysis of cortical RNA interestingly showed no reduction in Na/Pi cotransporter mRNA abundance even after three days of gentamicin treatment. CONCLUSION: We conclude that gentamicin inhibits Na/Pi cotransport activity by causing a decrease in the expression of the type II Na/Pi cotransport protein at the level of the proximal tubular apical BBM and that inhibition of Na/Pi cotransport activity is most likely mediated by post-transcriptional mechanisms.

Animals↗

PubMed2001

Glycosphingolipids modulate renal phosphate transport in potassium deficiency.

BACKGROUND: Potassium (K) deficiency (KD) and/or hypokalemia have been associated with disturbances of phosphate metabolism. The purpose of the present study was to determine the cellular mechanisms that mediate the impairment of renal proximal tubular Na/Pi cotransport in a model of K deficiency in the rat. METHODS: K deficiency in the rat was achieved by feeding rats a K-deficient diet for seven days, which resulted in a marked decrease in serum and tissue K content. RESULTS: K deficiency resulted in a marked increase in urinary Pi excretion and a decrease in the V(max) of brush-border membrane (BBM) Na/Pi cotransport activity (1943 +/- 95 in control vs. 1184 +/- 99 pmol/5 sec/mg BBM protein in K deficiency, P < 0.02). Surprisingly, the decrease in Na/Pi cotransport activity was associated with increases in the abundance of type I (NaPi-1), and type II (NaPi-2) and type III (Glvr-1) Na/Pi protein. The decrease in Na/Pi transport was associated with significant alterations in BBM lipid composition, including increases in sphingomyelin, glucosylceramide, and ganglioside GM3 content and a decrease in BBM lipid fluidity. Inhibition of glucosylceramide synthesis resulted in increases in BBM Na/Pi cotransport activity in control and K-deficient rats. The resultant Na/Pi cotransport activity in K-deficient rats was the same as in control rats (1148 +/- 52 in control + PDMP vs. 1152 +/- 61 pmol/5 sec/mg BBM protein in K deficiency + PDMP). These changes in transport activity occurred independent of further changes in BBM NaPi-2 protein or renal cortical NaPi-2 mRNA abundance. CONCLUSION: K deficiency in the rat causes inhibition of renal Na/Pi cotransport activity by post-translational mechanisms that are mediated in part through alterations in glucosylceramide content and membrane lipid dynamics.

Animals↗

PubMed2001

Perceptual grouping in two visually reliant species: humans (Homo sapiens) and Australian sea lions (Neophoca cinerea).

Kurylo, van Nest, and Knepper (1997 Journal of Comparative Psychology 111 126-134) have recently shown that hooded rats are able to judge the global orientation of an array of elements if orientation is signalled by the perceptual-grouping principle of proximity, but not if it is signalled by element alignment. Using a procedure designed to overcome some potential problems with the experiment of Kurylo et al, we found the same distinction in the perceptual processing of Australian sea lions. The sea lions were able to judge the orientation of arrays containing strong proximity and similarity information, but performed at chance levels judging arrays in which element alignment signalled global orientation. Human subjects were able to judge all three pattern types quickly and accurately. This is strong evidence of a qualitative distinction in the way in which perceptual grouping operates in humans and the non-human species tested. Whether this distinction is a consequence of evolutionary or experiential factors is a question for future research, but the mere fact of a qualitative difference holds important implications for our understanding of perceptual grouping.

Animals↗

PubMed2001

Acceptability of short-course rifampin and pyrazinamide treatment of latent tuberculosis infection among jail inmates.

STUDY OBJECTIVES: To determine whether short-course treatment of latent tuberculosis infection (LTBI) with 2 months of rifampin and pyrazinamide (2RZ) is well tolerated and leads to increased treatment completion among jail inmates, a group who may benefit from targeted testing and treatment for LTBI but for whom completion of > or = 6 months of isoniazid treatment is difficult because of the short duration of incarceration. DESIGN: Prospective cohort. SETTING: Large, urban county jail. PATIENTS: All inmates admitted to the Fulton County Jail who had positive tuberculin skin test results, normal findings on chest radiography, and expected duration of incarceration of at least 60 days. INTERVENTION: Inmates were offered 2RZ via daily directly observed therapy for 60 doses as an alternative to isoniazid therapy. MEASUREMENTS AND RESULTS: We measured the completion of 2RZ treatment and toxicity due to 2RZ treatment during incarceration. From December 14, 1998, through December 13, 1999, 1,360 new inmates had positive tuberculin skin test results and normal findings on chest radiography, and 168 new inmates had an expected duration of incarceration of > or = 60 days. One hundred sixty-six inmates (> 99%) were HIV-negative. Eighty-one inmates (48%) completed 60 doses of 2RZ treatment while incarcerated. Seventy-four inmates (44%) were released before completion. Treatment was stopped in 1 inmate (< 1%) for asymptomatic elevation of asparginine aminotransferase (> or = 10 times normal) and in 12 inmates (7%) for minor complaints. Twenty-one inmates had completed isoniazid treatment in the year before the availability of 2RZ, and 9 inmates completed isoniazid treatment in the year during the availability of 2RZ. CONCLUSIONS: 2RZ was acceptable to and well tolerated by inmates, and led to a marked increase in the number of inmates completing treatment of LTBI during incarceration.

Adult↗

PubMed2001

The evolution of the Fenway Community Health model.

Fenway Community Health was founded by community activists in 1971 in the Fenway neighborhood of Boston, Mass, and within a decade had rapidly expanded its medical services for gay men in response to the AIDS epidemic. Increased expertise and cultural competence in lesbian, gay, bisexual, and transgender (LGBT) care led to expansion of medical services to address broader community concerns, ranging from substance use to parenting issues to domestic and homophobic violence, as well as specialized programs for lesbians, bisexuals, and transgendered individuals. Fenway began as a grassroots neighborhood clinic. In 1975, the center recorded 5000 patient care visits; in 2000, Fenway's clinical departments recorded 50,850 visits by 8361 individuals, including more than 1100 individuals receiving HIV-associated care. The center now has more than 170 staff people responsible for clinical programs, community education, research, administration, planning, and development. Over the past few years, Fenway's annual budget has exceeded $10 million. Fenway has established standards for improved cultural competence about LGBT health issues for other health providers and has developed programs to educate the general community about specific LGBT health concerns. This health center may provide a model of comprehensive LGBT health services that have a local impact.

Acquired Immunodeficiency Syndrome↗

PubMed2001

A spoonful of sugar...: improving adherence to tuberculosis treatment using financial incentives.

OBJECTIVE: To determine whether incentives increase adherence to directly observed therapy (DOT) for tuberculosis (TB) treatment. METHODS: The TB program gave a five-dollar grocery coupon for each DOT appointment kept to 55 patients who had missed at least 25% of DOT doses over a 4-week period. Treatment completion rates were compared with an historic control group of 52 patients who began treatment a year earlier, who would have been eligible for incentives but did not receive them. RESULTS: Incentive program patients were more likely than control patients to complete therapy within 32 weeks (OR 5.73, 95%CI 2.25-14.84) and 52 weeks (OR 7.29, 95%CI 2.45-22.73). CONCLUSION: Patient incentives can increase adherence to DOT in TB programs.

Antitubercular Agents↗

PubMed2001

Salmonella typhi liver abscess.

We report on the first case of a typhoid liver abscess treated at the Chris Hani Baragwanath Hospital in Johannesburg, which responded well to percutaneous catheter drainage and intravenous ampicillin therapy.

Diagnosis, Differential↗

PubMed2000

A simple high performance liquid chromatographic method for the quantification of total cotinine, total 3'-hydroxycotinine and caffeine in the plasma of smokers.

A simple isocratic HPLC procedure has been developed for the quantification of caffeine and the nicotine metabolites cotinine, 3'-hydroxycotinine, cotinine glucuronide and 3'-hydroxycotinine glucuronide in the plasma of smokers. The glucuronide conjugates were determined indirectly via initial basic hydrolysis of the analyte sample followed by quantification of the resulting deconjugation product. Plasma was basified, extracted with dichloromethane, evaporated, the residue dissolved water and an aliquot part was analyzed by HPLC. The method utilized a Partisil-10 SCX cation-exchange column and an isocratic mobile phase of sodium phosphate buffer: methanol (92:8 v/v, 0.1 M, adjusted to pH 4.8 with triethylamine) at a flow rate of 1.5 ml/min. UV detection was at 254 nm. All solutes were separated with good resolution, and quantification was determined using an internal standard of N,N-diethylnicotinamide. The retention times were: caffeine 5.1 min, 3'-hydroxycotinine 7.2 min, N,N-diethylnicotinamide 9.5 min, and cotinine 15.5 min. Detection limits for caffeine, 3'-hydroxycotinine, cotinine, and total cotinine were 10 ng/ml; the detection limit for total 3'-hydroxycotinine was 20 ng/ml. The inter-day and intra-day variations for all analytes were between 1 and 8%. This analytical method is suitable for the determination of caffeine and nicotine metabolite levels in large numbers of clinical samples.

Caffeine↗

PubMed2000

A novel locus for autosomal recessive peripheral neuropathy in the EGR2 region on 10q23.

During our studies of Romany (Gypsy) families with hereditary motor and sensory neuropathy-Lom, we have identified a large kindred with two independently segregating autosomal recessive neuropathies. The novel disorder, named "hereditary motor and sensory neuropathy-Russe" (HMSNR), presented as a severe disabling form of Charcot-Marie-Tooth disease with prominent sensory loss, moderately reduced motor nerve conduction velocity, and a high threshold for electrical nerve stimulation. A genome scan in two branches of the large kindred detected linkage to the 10q22-q23 region containing the early growth response 2 gene (EGR2), a transcription factor with a key role in peripheral nerve myelination. The results of sequence analysis and the detection of an intragenic polymorphism allowed us to exclude EGR2 as the HMSNR gene. Further analysis done using linkage and recombination mapping refined the position of the HMSNR gene to a small interval on 10q23.2, flanked by markers D10S581 and D10S1742, telomeric to EGR2. In this interval, a conserved seven-marker haplotype is shared by all disease chromosomes, suggesting a single founder mutation. The homozygosity region is contained in bacterial-artificial-chromosome contig 1570 of the Sanger Centre physical map and has an estimated physical size of approximately 500 kb.

Charcot-Marie-Tooth Disease↗

PubMed2000

Common perceptions about strokes.

The frequency with which strokes occur and the devastating effects they can have make provision of general stroke information an essential element of public health education. This survey study sought to explore the general public's knowledge about various aspects of strokes. A questionnaire consisting of 4 open-ended, free-recall questions and 27 yes/no questions about the physiological processes, risk factors, warning signs, and functional consequences of strokes was administered orally to 190 individuals at a regional shopping mall. Additional items provided information about respondents' ages, ethnicity, educational status, and personal experiences with strokes. Free recall results indicated that approximately two-thirds of the survey respondents could provide correct or partially correct explanations of stroke physiology and could name at least one stroke warning sign; over 90% of respondents could name at least one stroke risk factor and one functional consequence of stroke. Most respondents reported acquiring information about strokes through personal acquaintances, popular media, or general life experiences rather than from professionals or as part of their formal schooling. Suggestions about needed content in general educational programs came from respondents' misconceptions about physiological processes, risk factors, warning signs, and functional consequences of strokes.

Activities of Daily Living↗