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J Thomas

Publications and source records attributed to J Thomas.

At least 181 records · Page 10Linked to original sources
PubMed2000

Increased susceptibility to gingival colonization by specific HACEK microbes in children with congenital heart disease.

It is well established that infective endocarditis (IE) involving the HACEK (Hemophilus, Actinobacillus, Cardiobacter, Eikenella, Kingella) group of microbes occurs in patients with congenital heart defects (CHD) and in those with prosthetic grafts. Dental caries and gingival disease have been presumed to be the focus of microbial shedding. The purpose of this study was to determine if children with CHD had a more severe gingival inflammatory condition and harbored the HACEK group of microbes to a greater extent than normal children. Two groups of 12 age and sex matched children were selected for this study. The experimental group consisted of twelve children with CHD, 1-1/2 to 8 years of age. The control group consisted of 12 healthy children 2 to 8 years of age. Each child had a gingival index score recorded as described by Massler. Subgingival cultures were obtained. Gingival samples were cultured for HACEK microbes and total Streptococcus (spp) using standard techniques. Fisher's exact test was performed with significance defined at P < 0.05. Children with CHD had more severe gingival inflammatory index than the control group (P < 0.05). 8/12 CHD patient had Actinobacillus actinomycetemcomitans (A.a.) as compared with 2/12 controls (P < 0.05). Furthermore, all cyanotic CHD patients (4/4) had A.a. whereas, only 2/12 controls did (P < 0.05). 4/12 CHD patients harbored Eikenella corrodens (E.c.) compared to 1/12 controls (N.S.). There was no significant difference in colonization with E.c. or A.a. between cyanotic and acyanotic patients. No significant difference in total Streptococcus (spp) was found between the two groups. This study suggests that children with CHD have a more severe gingival inflammatory index and are colonized with specific HACEK microbes more so than normal children.

Actinobacillus↗
PubMed2000

Treatment with subantimicrobial dose doxycycline improves the efficacy of scaling and root planing in patients with adult periodontitis.

BACKGROUND: In a previous study, subantimicrobial dose doxycycline (SDD) significantly improved clinical parameters associated with periodontal health in patients with adult periodontitis (AP) when used as an adjunct to a maintenance schedule of supragingival scaling and dental prophylaxis. In this double-blind, placebo-controlled, parallel-group, multicenter study, the efficacy and safety of SDD were evaluated in conjunction with scaling and root planing (SRP) in patients with AP. METHODS: Patients (n = 190) received SRP at the baseline visit and were randomized to receive either SDD 20 mg bid or placebo bid for 9 months. Efficacy parameters included the per-patient mean changes in clinical attachment level (CAL) and probing depth (PD) from baseline, the per-patient percentages of tooth sites with attachment loss (AL) > or = 2 mm and > or = 3 mm from baseline, and the per-patient percentage of tooth sites with bleeding on probing. Prior to analysis, tooth sites were stratified by the degree of disease severity evident at baseline RESULTS: In tooth sites with mild to moderate disease and severe disease (n = 183, intent-to-treat population), improvements in CAL and PD were significantly greater with adjunctive SDD than with adjunctive placebo at 3, 6, and 9 months (all P <0.05). In tooth sites with severe disease, the per-patient percentage of sites with AL > or = 2 mm from baseline to month 9 was significantly lower with adjunctive SDD than with adjunctive placebo (P<0.05). Improvements in clinical outcomes occurred without detrimental shifts in the normal periodontal flora or the acquisition of doxycycline resistance or multiantibiotic resistance. SDD was well tolerated, with a low incidence of discontinuations due to adverse events. CONCLUSIONS: The adjunctive use of SDD with SRP is more effective than SRP alone and may represent a new approach in the long-term management of AP.

Adult↗
PubMed2000

Long-term treatment with subantimicrobial dose doxycycline exerts no antibacterial effect on the subgingival microflora associated with adult periodontitis.

BACKGROUND: The purpose of this study was to determine whether treatment with subantimicrobial dose doxycycline (SDD), 20 mg bid, exerted an antimicrobial effect on the microflora associated with adult periodontitis. METHODS: Following the approval of the protocol and informed consent forms by the respective IRBs at the University of Florida and West Virginia University, 76 subjects with adult periodontitis were entered and randomly assigned to receive SDD or placebo. A split-mouth design was utilized, with each subject receiving subgingival scaling and root planing (SRP) in two quadrants immediately following baseline data collection, while the remaining two quadrants were left unscaled (non-SRP). Microbial samples were collected prior to treatment, after 3, 6, and 9 months of treatment, and after 3 months of no treatment. The samples were examined by microscopy and by enumeration on selective and non-selective media. RESULTS: All treatments resulted in statistically significant decreases in the proportions of spirochetes and motile rods (P <0.05) and in an increase in the proportion of coccoid forms (P <0.0001) relative to baseline. No between-treatment differences were detected between the SDD and placebo treatments in either the SRP or non-SRP design, with the exception of the small and large spirochetal groups. The spirochetal proportions present in the SDD group were significantly lower (P<0.05) than the paired placebo group during the 9-month treatment and was preceded by a significant decrease (P<0.01) in the proportion of microbiologic sample sites that bled on probing. No between- treatment differences were detected in any of the other microbial parameters. CONCLUSION: The microbial differences observed were attributed to the anticollagenase and anti-inflammatory properties of SDD and not to an antimicrobial effect.

Adult↗
PubMed2000

Long-term use of subantimicrobial dose doxycycline does not lead to changes in antimicrobial susceptibility.

BACKGROUND: Adjunctive subantimicrobial dose doxycycline (SDD) with scaling and root planing leads to improved clinical parameters of adult periodontitis, but has raised questions about potential changes in antibiotic susceptibility of the host microflora. Our four studies assessed whether long-term SDD changes antibiotic susceptibility of the oral microflora in adults with periodontitis. METHODS: In studies 1 and 2, adult patients with periodontitis were randomized to receive SDD 10 mg qd, 20 mg qd, 20 mg bid, or placebo. In study 3, patients were randomized to receive SDD 20 mg bid or placebo. No medication was administered in study 4, a follow-up to study 3. Subgingival plaque samples were collected at baseline (all studies) and at 12, 15 to 18, and 24 months (study 1); 12, 18, and 27 months (study 2); 3, 6, and 9 months (study 3); and 3 months post-study 3 (study 4). Antimicrobial susceptibility of isolated bacteria was assessed by: 1) minimum inhibitory concentration (MIC) levels (studies 1 and 2); 2) cross-resistance to non-tetracycline antibiotics (studies 2 and 3); and 3) the proportion of doxycycline-resistant isolates (studies 3 and 4). RESULTS: Organism MIC levels remained constant among all treatment groups at 18 and 24 months compared with baseline (study 1). Observed changes in susceptibility at 12 and 18 months for the 20 mg groups were attributed to the limited number of isolates tested (study 1). There were no statistically significant differences in the proportion of doxycycline-resistant isolates among treatment groups (studies 3 and 4), and no evidence of multi-antibiotic resistance (studies 3 and 4) or cross-resistance (studies 2 and 3) at any timepoint. CONCLUSION: Long-term SDD does not contribute to changes in antibiotic susceptibility.

Actinomyces↗
PubMed2000

Clinical and psychopharmacologic factors influencing family burden in refractory schizophrenia. The Department of Veterans Affairs Cooperative Study Group on Clozapine in Refractory Schizophrenia.

BACKGROUND: This study compares the effect of clozapine and haloperidol and identifies other factors related to family burden as experienced by relatives of patients with refractory schizophrenia (DSM-III-R). METHOD: Of 423 patients participating in a multisite randomized clinical trial, 221 identified a family member who was actively involved in their care and who agreed to complete a standardized measure of family burden at 6 weeks and 3, 6, 9, and 12 months after randomization, simultaneous with comprehensive patient assessments. RESULTS: Patient factors most consistently correlated with greater family burden were symptom severity, days living in the community (i.e., not in the hospital), and frequency of family contact. Among family members, clozapine was associated with significantly (p = .048) greater reduction in feelings of dissatisfaction related to providing support to the patient, but not in objective measures of support, amount of worry the patient engendered, or days of missed employment or household activity. Although clozapine reduces symptoms, thus lowering family burden, it also increases days living in the community, which tends to increase family burden, perhaps canceling out the benefit to families of reduced symptoms. CONCLUSION: Clozapine has a small but significant effect on the experience of families of patients. This is the first study to demonstrate that effective pharmacotherapy may be of some benefit to families as well as to patients.

Adult↗
PubMed2000

[Cacchi and Ricci's disease. Radiology, epidemiology and biology].

OBJECTIVES: Medullary sponge kidney corresponds to the precaliceal dilatation of renal tubules. The purpose of this article is to draw attention to some of the radiological, epidemiological and laboratory features of this disease. MATERIAL AND METHOD: 500 cases of radiopaque renal stones, corresponding to 310 men and 190 women, were reviewed. One or several urographies, early urographic films, and blood calcium phosphate and 24-hour urinary calcium phosphate and oxalate assessments were available for all subjects. We have added to this series an identical study on 100 cases of stones in North African subjects. RESULTS: From a radiographic point of view, this study shows the value of early urography films, performed between the 2nd and 4th minutes after intravenous injection of iodinated contrast agent, which visualize abnormal opacification of the renal pyramids, before or at the same time as that of the bases of the calices. A radiological sign, not reported in the medical literature, is a clear border between abnormal opacification of the papillae and that of the calices, observed in one or several papillocaliceal zones, which facilitates the diagnosis of medullary sponge kidney. In this series of 500 cases of renal stones, the radiological diagnosis of medullary sponge kidney was established in 103 cases: 20.6%. The distribution varies according to sex, 54 out of 310 (12.59%) in men, 53 out of 190 (27.89%) in women; difference p < 0.001. We found only 3 cases of medullary sponge kidney in the series of 100 cases of radiopaque stones in North African subjects. In terms of laboratory parameters, 24-hour urine tests showed hypercalciuria in 61 out of 103 cases (59.22%), or hyperoxaluria in 66 out of 103 cases (64.08%), while 41 out of 103 cases (39.81%) presented both disorders. Urinary calcium oxalate assessments were normal in 20 out of 103 cases (19.42%). Hyperparathyroidism was never detected in combination with medullary sponge kidney. CONCLUSION: This study shows the value of early urography films for the diagnosis of medullary sponge kidney and demonstrates a useful diagnostic radiological sign: a clear border between abnormal urographic opacification of the papillae and calices. It shows the much higher frequency of medullary sponge kidney in patients with radiopaque stones, with a higher rate in women than in men, and a low frequency in North African subjects, that needs to be confirmed. This study also emphasizes the frequency of hypercalciuria and especially hyperoxaluria, and even the combination of these two disorders in medullary sponge kidney.

Female↗
PubMed2000

Medication continuation and compliance: a comparison of patients treated with clozapine and haloperidol.

BACKGROUND: This study compares medication continuation and regimen compliance with the atypical antipsychotic medication clozapine versus the conventional antipsychotic haloperidol. METHOD: Data from a 15-site double-blind, randomized clinical trial (N = 423) were used to compare patients with DSM-III-R schizophrenia assigned to clozapine or haloperidol in terms of duration of participation while taking the randomly assigned study drug (continuation) and the proportion of prescribed pills that were taken (compliance). Multiple regression analysis was used to determine the relationship of baseline characteristics and measures of clinical change to continuation for the entire sample and for patients assigned to each medication. RESULTS: Patients assigned to clozapine continued taking the study drug for a mean of 35.5 weeks as compared with only 27.2 among patients assigned to haloperidol (F = 4.45, df = 1,422; p = .0001). No differences were found between the groups in the proportion of prescribed pills that were returned at any timepoint. Among patients assigned to haloperidol, poorer continuation was associated with being older and greater continuation with receiving public support. Among patients on clozapine treatment, continuation was poorer among African American patients and greater among patients who showed reduced clinical symptoms and akathisia. Continuation with clozapine was greater even after adjusting for these factors. CONCLUSION: Continuation with medication is greater with clozapine than haloperidol and is partly explained by greater symptom improvement and reduced side effects. No differences were found in regimen compliance.

Adult↗
PubMed2000

Intergenerational effects of high socioeconomic status on low birthweight and preterm birth in African Americans.

As socioeconomic status (SES) increases, the incidence of low birthweight and preterm birth decreases irrespective of social class. However, low birthweight remains twice as high for African-American women as for white women even when SES is controlled. This study examines to what extent second generation high SES African-American women experience improvement in birthweight and gestational age. One hundred eighty-nine former Meharry students were surveyed. Identified were 934 births that are the children and grandchildren of these students who matriculated at Meharry. These infants are compared with a cohort of white mothers from a study in the School of Public Health at Yale University. Low birthweight was reduced in the third generation high SES African-American children (6.9%) from the second generation (11.4%) but remained higher than white children (3.3%). Results showed that African-American third generation children remained at higher risk for low birthweight than were white children (relative risk [RR], 1.78; 95% confidence interval [CI], 1.03, 3.09). Similar results were observed for preterm delivery where the increased risk to third generation African-American children was 3.16 (1.89, 5.27). Persistent strong ethnic differences in birthweight in this high SES cohort (OR = 3.16, 95% CI, 1.89-5.27) support a conclusion that African-American women have birthweight distributions that are somewhat lighter than white women. This may explain a portion of current ethnic differences in birthweight. It is also possible that persistent psychosocial and behavioral factors continue to negatively influence birthweight, even in second generation high SES African-American mothers. This explanation will require identification of powerful risk factors, which are largely unrelated to those presently under investigation.

Adult↗
PubMed2000

Biochemical and molecular approaches to understanding protein import into peroxisomes.

Peroxisomes are eukaryotic organelles that perform diverse and variable functions. Although genetic studies in yeasts and mammals have identified approximately 20 genes (PEX genes) required for the biogenesis of this important organelle, biochemical studies of protein targeting and import have lagged behind and in many cases we have no idea of the function of the PEX gene products (peroxins). Using an import assay in vitro derived from sunflower cotyledon cells and recombinant proteins, we have obtained translocation intermediates on the peroxisome import pathway and are using cross-linking to identify interacting partners. We have also used antibodies raised against human PEX14 to inhibit the import of matrix proteins in this system. To obtain homologous antibodies for inhibition experiments, to immunoprecipitate cross-linked products and to enable us to study the import pathways of peroxins we have cloned and characterized plant orthologues of three PEX genes, PEX6, PEX10 and PEX14.

ATPases Associated with Diverse Cellular Activitie↗
PubMed2000

Bioavailability study of oral liquid and tablet forms of alpha-difluoromethylornithine.

The purpose of this study was to assess the bioavailability of two oral preparations of difluoromethylornithine (DFMO). The current preparation of DFMO is a liquid with a concentration of 0.2 gram/ml that must be drawn up into a syringe and dispensed into a small medicine glass. This form of DFMO causes wastage of the medication. The liquid form also makes compliance and blinding difficult. Recently, a new coated tablet preparation has become available from Ilex Oncology Services (San Antonio, TX). The coated tablets are 0.25 gram and are scored. The tablet form should increase compliance by making it much easier for the subject to take the medication. This report compares the bioavailability of both preparations with the goal of demonstrating equivalence of the preparations. Ten normal subjects entered the cross-over study in which the order in which they would receive the liquid or tablet preparation of DFMO was randomized. The study was designed with the objective of establishing the bioequivalence of a tablet preparation of DFMO at daily dose 0.5 gram/m2 and a liquid preparation of DFMO at the same daily dose. The mean area under the time-by-concentration curves (microM x hours) for the liquid and tablet preparations was 368.2 and 370.4, respectively. The peak concentrations for the liquid and tablet preparations were 47.3 and 48.2 microM, respectively. No statistically significant differences were seen in these parameters, in time to peak concentration, or in serum half-life.

Administration, Oral↗
PubMed2000

Ten years of liver transplantation at Groote Schuur Hospital.

INTRODUCTION: Liver transplantation has evolved from an experimental procedure to being the treatment of choice for many patients with end-stage liver disease, and is performed on a routine basis in most major centres throughout the world. However, certain situations peculiar to developing countries have a major impact on liver transplant programmes in these countries. We present the results of the liver transplant programme in Cape Town. PATIENTS AND METHODS: All patients undergoing orthotopic liver transplantation at Groote Schuur Hospital and Red Cross War Memorial Children's Hospital were included in this report. Standard surgical techniques were used for procuring the donor liver, the recipient hepatectomy and the subsequent implantation of the liver. All patients received standardised peri-operative management; in particular, the immunosuppressive protocol consisted of cyclosporin, steroids and azathioprine. Since October 1988, 83 patients have undergone 89 orthotopic liver transplants. There were 44 adults and 39 children, the age range being from 6 months to 56 years. The commonest indications for hepatic transplantation in adults included cryptogenic cirrhosis, auto-immune hepatitis and primary sclerosing cholangitis. In children biliary atresia was the commonest cause of liver failure. RESULTS: Of the 81 patients transplanted, 50 are alive and well with follow-up ranging from 2 months to 9.5 years. The cumulative graft survival rate was 72% at 1 year and 61% at 5 years. Six patients have undergone re-transplantation and 4 patients have had combined liver/kidney transplants. De novo hepatitis due to hepatitis B virus (HBV) has occurred in 8 patients following transplantation. Subsequent investigation has shown that 5 of the donors of these livers were hepatitis B core antibody (HBcAb)-positive, while information on the remaining 3 was not available. Tuberculosis (TB) has been a significant problem in 4 patients, with 2 deaths precipitated by anti-TB drug-induced hepatitis. Post-transplant lymphoproliferative disorder was also responsible for significant postoperative morbidity. CONCLUSION: Orthotopic liver transplantation has been established at Groote Schuur Hospital as the treatment of choice for selected patients with chronic end-stage liver disease. However, hepatitis B and TB appear to present a problem. The particularly high prevalence of HBV carrier status in our donor population may necessitate the use of living donors in the future.

Adolescent↗
PubMed2000

Comparison of videothoracoscopy and axillary thoracotomy for the treatment of spontaneous pneumothorax.

Surgical treatment of spontaneous pneumothorax can be done through a thoracotomy or a video-thoracoscopic approach. Although the videothoracoscopic technique is currently popular it is not obviously superior to a more traditional axillary thoracotomy approach. We compared our recent experience with both techniques to determine the optimal surgical treatment for spontaneous pneumothoraces. A retrospective review of 79 patients treated surgically (34 thoracotomy and 45 thoracoscopy) for spontaneous pneumothoraces was done. Patients were treated between 1991 and 1997. Patients older than 60 years of age and those with spontaneous pneumothoraces secondary to generalized pulmonary emphysema were excluded. There were no operative deaths. Recurrence rate [thoracotomy, two of 34; thoracoscopy, three of 45 (P < 0.89)], air leak exceeding 7 days [thoracotomy, three of 34; thoracoscopy, three of 45 (P < 0.73)], operating room times [thoracotomy, 54 +/- 26 minutes; thoracoscopy, 53 +/- 16 minutes (P < 0.59)], and postoperative length of stay [thoracotomy, 5.7 +/- 4.3 days; thoracoscopy, 4.7 +/- 4.4 days (P < 0.26)] were not significantly different for the two techniques. We conclude that axillary thoracotomy and videothoracoscopy are equally effective surgical treatments for spontaneous pneumothoraces. A large randomized trial would be needed to determine whether one approach is truly superior to the other.

Adult↗
PubMed2000

[Cystine lithiasis: study of a series of 116 cases].

INTRODUCTION: Cystine stones is a rare disease, related to a genetic metabolic disease. Its management must treat both the stones and their complications, and prevent recurrences by controlling cystinuria. OBJECTIVE: The objective of this study was to define the natural history of cystine stones, identify reliable diagnostic criteria and propose a simple treatment regimen. MATERIAL AND METHOD: The authors studied the clinical, biochemical and radiological data of a retrospective series of 116 cases, treated by the same urologist between 1953 and 1999. RESULTS: Cystinuria is often diagnosed in young adults on the basis of urine biochemistry (Brand's reaction, urinary cystine assay) or spectrophotometric analysis of the stones or urinary crystals. This assessment, not performed routinely, must be guided by a family history, recurrent stones or following failure of lithotripsy. The appearance of the stones, macroscopically a waxy yellow, radiologically only slightly opaque with a large component in the renal pelvis associated with a small round caliceal stones, is highly suggestive. Radiological assessment by IVU is generally sufficient. Treatment of the disease is medical and surgical: dietary measures, alkalinization of the urine and possibly drug treatments, are associated with extracorporeal lithotripsy or surgical treatment. These modalities eliminate cystine stones in 70% of cases. Recurrent stones are observed in 42% of cases followed for more than 5 years, mainly due to the presence of residual fragments (60% of recurrences). Surveillance and dietary measures must be maintained for life. Surveillance is based on biannual radiographic follow-up (plain x-rays +/- ultrasound) to detect and consequently treat small stones. A test for cystinuria must be proposed to all relatives of affected patients. CONCLUSION: This disease presents very polymorphic clinical features and clinical course. It can be responsible for impaired renal function and must therefore be investigated in the presence of suggestive clinical signs or history to avoid a delayed diagnosis, as treatment modalities are available to decrease the frequency of recurrence and which can potentiate treatment by surgical or lithotripsy. However, there are no predictive factors of deterioration of the disease, and biannual surveillance, for life, is essential to detect and treat small stones.

Adolescent↗
PubMed2000

[Hydroposturotherapy and residual lithiasis after lithotripsy].

OBJECTIVE: The authors report the results of hydroposturotherapy on elimination of residual stone fragments after extracorporeal lithotripsy. MATERIALS AND METHODS: 417 subjects with residual stone fragments after one or several lithotripsy sessions, who failed to eliminate any fragments over a period of 3 to 6 months, or even 12 months, before starting treatment, were submitted to intensive water intake and appropriate daily hydrotherapy. Hydrotherapy was adapted to each case and, in the case of residual lower caliceal stones, the subjects were placed in the vertical position, head downwards with the feet in the air, to facilitate migration of stone fragments. RESULTS: The subjects examined their urine at each micturition and collected any fragments expelled. Overall, in the population of 417 subjects treated in this way for three weeks, partial or complete expulsion was obtained in 282 cases (67.6%). Stone expulsion was obtained in 218 of the 305 cases (71.5%) of residual lower caliceal stones and 64 of the 112 cases (57.1%) of middle or upper caliceal stones. Stone expulsion, when obtained, usually started by the first, second or third day of treatment. CONCLUSION: This study shows that hydroposturotherapy can improve the elimination of residual stone fragments following extracorporeal lithotripsy.

Adolescent↗
PubMed2000

Candid-B cream in the treatment of candidiasis with inflammatory dermatoses--National Study Group.

Physicians (n = 84) across the country prescribed candid-B cream (clotrimazole 1% + beclomethasone dipropionate 0.025%) on 822 patients suffering from candidiasis with inflammatory diseases to evaluate the efficacy and safety of the combination. The results showed reduction in severity was more than 80% for all symptoms/signs except scaling and lichenification where the reduction was 76.05% and 66.03% respectively. Only one patient complained of adverse reaction. So in the treatment of coexisting candidiasis and inflammatory dermatoses the combination of clotrimazole 1% + beclomethasone 0.025% (candid-B cream) was found to be highly effective.

Administration, Topical↗
PubMed2000

Liver transplantation in children--the Red Cross War Memorial Children's Hospital experience.

Liver transplantation for infants and children has been available in South Africa for more than a decade. Current concerns have shifted from an initial target of early post-transplant survival to quality of life in the long term. Since 1985, 175 infants and children have been assessed, with 104 accepted for transplantation. Fifty have had orthotopic liver transplants (OLTx), 48 (3 retransplants) in Cape Town and 2 abroad. Biliary atresia was the most frequent diagnosis (52%) followed by acute liver failure (ALF) (16%). Waiting list mortality has remained high (15%), particularly for the ALF group (50%). Thirty-four patients survive 1 month--14 years post-transplant. Early post OLTx mortality was low (7%) but late morbidity and mortality (23%) were mainly due to viral infection: de novo hepatitis B (5 patients, 2 deaths), EBV-related post-transplantation lymphoproliferative disease (PTLPD) (6 patients, 4 deaths) and CMV disease (9 patients, 4 deaths). Tuberculosis prophylaxis, required in 6 cases, resulted in major morbidity in 1. Hypertension requiring medication along with some compromise of renal function has been present in all but 2 patients. However, all those of school-going age (20) attend school normally and remain in good health and only 3 of the survivors have abnormal liver function tests. Successful liver transplantation is possible in a developing country with limited resources. Scarcity of virus-free donors (HBV and HIV) leading to waiting list mortality and infrequent retransplantation along with long-term consequences of immunosuppression (infection, lymphoma and renal toxicity) remain problems.

Child↗
PubMed2000

Lectures.

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Journal Article↗