Biomedical subjects

T M Daniel

Publications and source records attributed to T M Daniel.

At least 37 records · Page 2Linked to original sources

PubMed1997

Radiology of pulmonary turberculosis and human immunodeficiency virus infection in Gulu, Uganda.

Pulmonary tuberculosis is a major complication of human immunodeficiency virus (HIV) infection. The radiographic manifestations of pulmonary tuberculosis in HIV-infected patients are not typical of those seen in immunologically normal individuals. We sought to determine whether these manifestations provide clues to the pathogenesis of tuberculosis in HIV-infected persons. The radiographic manifestations of pulmonary tuberculosis were reviewed and classified in 82 HIV-positive and 53 HIV-negative tuberculous patients in Gulu, Uganda. Pulmonary presentations of tuberculosis were more acute in HIV-positive patients, and often included hilar or mediastinal adenopathy and pleural effusions, findings typical of primary tuberculosis in immunologically normal individuals. Many patients also had chronic forms of tuberculosis, either alone or in combination with acute disease. The findings of this study support the hypothesis that reactivation of latent infections and progression of pre-existent chronic disease produce a substantial portion of the tuberculosis burden of HIV-positive persons in Uganda. Tuberculosis control efforts should extend beyond efforts at decreasing transmission of new infections.

AIDS-Related Opportunistic Infections↗

PubMed1996

Induction of monocyte expression of tumor necrosis factor alpha by the 30-kD alpha antigen of Mycobacterium tuberculosis and synergism with fibronectin.

Native 30-kD antigen, also known as alpha antigen, is a fibronectin-binding protein that is secreted by live Mycobacterium tuberculosis. This antigen may play an important biological role in the host-parasite interaction since it elicits delayed type hypersensitivity response and protective immunity in vivo and T lymphocyte blastogenesis and IFN-gamma production in vitro. In the present study, we show that, TNF-alpha protein is produced in monocyte culture supernatants in response to 30-kD antigen and the level is as high as that to purified protein derivative of M. tuberculosis. This stimulatory effect was not due to contamination with either bacterial lipopolysaccharide or mycobacterial lipoarabinomannan. The preincubation of monocytes with plasma fibronectin significantly enhanced the release of TNF-alpha into the culture supernatants in response to 30-kD antigen. This effect was blocked by polygonal antibody to plasma fibronectin. In contrast, the monocytic cell line U937 failed to release TNF-alpha protein in the culture supernatants in response to 30-kD antigen with or without preincubation with plasma fibronectin. To determine whether this observation was due to differential binding of the 30-kD to fibronectin on these cells, a cell based ELISA was used. Pretreatment of monocytes with fibronectin enhanced their binding of the 30-kD antigen. U937 cells bound the 30-kD antigen weakly with or without fibronectin pretreatment. These results indicate that 30-kD antigen which is a known secretary antigen of M. tuberculosis is a stimulus for human monocytes to express TNF-alpha and that stimulatory effect may be mediated through plasma fibronectin.

Antigens, Bacterial↗

PubMed1996

Origin and interstate spread of a New York City multidrug-resistant Mycobacterium tuberculosis clone family.

OBJECTIVE: To determine whether isolates of Mycobacterium tuberculosis from New York and elsewhere that are resistant to four or more primary antimicrobial agents and responsible for widespread disease in the 1990s represent a newly emerged clone or a heterogeneous array of unrelated organisms. SETTING: New York City area and selected locations in the United States. PATIENTS: M tuberculosis isolates from 1953 patients in New York and multidrug-resistant isolates from six patients from other US communities. DESIGN: Convenience sample of all M tuberculosis strains (M tuberculosis isolates resistant to rifampin, streptomycin, isoniazid, and ethambutol, and sometimes ethionamide, kanamycin, capreomycin, or ciprofloxacin) submitted to the Public Health Research Institute Tuberculosis Center since 1991 and samples submitted to the Centers for Disease Control and Prevention from throughout the United States. The samples submitted were representative of the New York City strains of M tuberculosis. MAIN OUTCOME MEASURE: Characterization of resistant M tuberculosis strains studied by IS6110 and polymorphic GC-rich repetitive sequence (PGRS) hybridization patterns, multiplex polymerase chain reaction (PCR) analysis, and automated DNA sequencing of genes containing mutations associated with resistance to rifampin (rpoB), isoniazid (katG and inhA locus), and streptomycin (strA and rrs). RESULTS: Multidrug-resistant M tuberculosis isolates were recovered from 253 New York City patients and had the same or closely allied IS6110 and PGRS patterns, multiplex PCR type, and gene mutations associated with resistance to rifampin, isoniazid, and streptomycin. Isolates with these same molecular characteristics were recovered from patients in Florida and Nevada, health care workers in Atlanta, Ga, and Miami, Fla, and an individual who recently moved from New York City to Denver, Colo, and caused disease or skin test conversion in at least 12 people in a nursing home environment. CONCLUSIONS: The results document the molecular origin and spread of progeny of a closely related family of multidrug-resistant M tuberculosis strains that have recently shared a common ancestor and undergone clonal expansion. The multidrug-resistant phenotype in these organisms arose by sequential acquisition of resistance-conferring mutations in several genes, most likely as a consequence of antibiotic selection of randomly occurring mutants in concert with inadequately treated infections. Dissemination of these difficult-to-treat bacteria throughout New York City and to at least four additional US cities has adverse implications for tuberculosis control in the 21st century.

Antitubercular Agents↗

PubMed1996

Postpneumonectomy syndrome with an ipsilateral aortic arch after left pneumonectomy.

BACKGROUND: Previous reports have described bronchial obstruction after left pneumonectomy (so-called post-pneumonectomy syndrome) in the presence of a right aortic arch with the bronchus being compressed between the ascending aorta and thoracic spine. This study reports on 4 patients with left postpneumonectomy syndrome in the presence of a normally located left aortic arch and ascending thoracic aorta. METHODS: The case histories of 4 patients with this syndrome were reviewed and several features common to all 4 were noted. In each case, the obstruction was thought to be due to a clockwise rotation of the mediastinum with bronchial compression occurring between the right main pulmonary artery and thoracic spine. RESULTS: Three patients were treated by repositioning of the mediastinum, and all 3 obtained relief of their dyspnea. In these cases, permanent repositioning was ensured by the insertion of a prosthesis filled with saline solution. The fourth patient was successfully treated by resection of a portion of the adjacent thoracic vertebra. CONCLUSIONS: Postpneumonectomy syndrome can occur after a left pneumonectomy in the absence of a right aortic arch. We suggest that mediastinal repositioning with a prosthesis filled with saline solution is simple, is safe, and results in complete relief of preoperative symptoms.

Adult↗

PubMed1996

Bacille Calmette Guérin immunization of health care workers exposed to multidrug-resistant tuberculosis: a decision analysis.

SETTING: North American health care workers with exposure to multidrug-resistant tuberculosis. OBJECTIVE: To evaluate the relative utilities of bacille Calmette Guérin (BCG) immunization and post-infection chemoprophylaxis for the protection of health care workers exposed to multidrug-resistant Mycobacterium tuberculosis. DESIGN: Decision analysis using SMLTREE software and published data for probabilities. RESULTS: BCG vaccination was preferred by a small margin over post-infection chemoprophylaxis. Sensitivity analysis revealed that possible changes in probability values used tended to tilt the result towards use of BCG vaccination. The threshold for protective efficacy of BCG vaccination was 26%. CONCLUSIONS: BCG vaccination should be considered for health care workers in environments where there is a substantial risk of exposure to multidrug-resistant tuberculosis.

Antitubercular Agents↗

PubMed1996

Lung volume reduction surgery. Case selection, operative technique, and clinical results.

OBJECTIVE: A clinical study was undertaken to define optimal preoperative strategies and intraoperative techniques that would result in the least morbidity and maximum physiologic improvements in patients with end-stage emphysema selected for lung volume reduction surgery. BACKGROUND: Lung volume reduction surgery recently has been advocated as an alternative or a bridge to lung transplantation for patients with end-stage chronic obstructive pulmonary disease. The risks, benefits, and long-term results have not been clarified. METHODS: Twenty-six patients underwent lung volume reduction surgery with a 3-month follow-up on 17 patients. Preoperative and postoperative changes in pulmonary function parameters, quality of life, and oxygen requirement were analyzed. The value of preoperative localization of diseased lung segments and how this affects intraoperative resection is addressed. RESULTS: Forty-nine percent improvement in FEV1 (forced expiratory volume in 1 second) and 23% improvement in FVC (forced vital capacity) were seen after lung volume reduction surgery. Supplemental oxygen requirement was decreased and 79% of patients reported a much better quality of life. Mortality was 3.8% and air leak morbidity was 18%. CONCLUSIONS: Lung volume reduction surgery can predictably improve objective and subjective pulmonary function in selected patients with end-stage emphysema with low morbidity and mortality. Careful patient selection, accurate preoperative localization of diseased target areas, skilled anesthetic technique, meticulous operative approach, and intense postoperative support are essential to achieve favorable results.

Adult↗

PubMed1996

Thoracoscopic sympathectomy.

Thoracoscopic sympathectomy has become the most widely used approach to cervicothoracic sympathectomy. Appropriate selection of cases and a knowledge of the regional anatomy are essential in achieving good clinical results. The physiology and anatomy of the upper thoracic sympathectomy system and the indications, contraindications, and complications of the operation are described. The technique of the operation as done at the University of Virginia is then presented in a step-by-step manner.

Ganglia, Sympathetic↗

PubMed1995

Isolation and characteristics of Mycobacterium avium complex from water and soil samples in Uganda.

SETTING: Mycobacterium avium complex organisms have not been isolated from late stage AIDS patients in Uganda. This could possibly be due to the absence of M. avium complex in the Uganda environment. OBJECTIVE AND DESIGN: Determine whether M. avium complex organisms could be isolated from water and soils collected in the living environment of Ugandan AIDS patients. RESULTS: Representatives of the M avium complex were isolated from 3 of 7 (43%) water and 3 of 7 (43%) soil samples collected in Kampala, Uganda. The average number of colony-forming units per ml water was 3.3 and average colony-forming units per gram of soil was 7825. In terms of growth characteristics, antimicrobial susceptibility patterns, and the presence or absence of plasmids and IS901, Ugandan M. avium complex isolates were similar to those isolated from the US and European AIDS patients and their environment. CONCLUSIONS: M. avium complex organisms sharing genetic and physiological characteristics of M. avium complex isolates recovered from patients with AIDS can be isolated from water and soil samples in Uganda.

Colony Count, Microbial↗

PubMed1995

Stroke rate is markedly reduced after carotid endarterectomy by avoidance of protamine.

PURPOSE: Postoperative neurologic injury remains a significant risk of carotid endarterectomy. Mechanisms include embolization of debris and formation of thrombus on the newly endarterectomized surface. We hypothesized that the risk of postoperative neurologic injury would be lower in those patients who did not receive protamine for reversal of heparin anticoagulation. METHODS: We reviewed 348 consecutive primary carotid endarterectomies performed since January 1, 1986, to determine the relationship between surgical outcomes and reversal of heparin anticoagulation. Patients undergoing additional simultaneous cardiovascular procedures were excluded. One hundred ninety-three patients received protamine after completion of the endarterectomy. The remaining 155 patients did not receive any protamine. RESULTS: All patients in both groups survived to discharge. There were no strokes in those patients who did not receive any protamine; however, the stroke rate in the protamine group was 2.6% (5 of 193), p < 0.045. The incidence of hematoma requiring reexploration was 1.0% (2 of 193) and 1.9% (3 of 155) in the protamine and no-protamine groups, respectively (p = NS). Intraoperative shunting was used more frequently in the no-protamine group (84% vs 67%, p < 0.001), and patch angioplasty was performed more frequently in the protamine group (35% vs 15%, p < 0.001). However, neither shunting nor patching significantly influenced stroke rates. CONCLUSIONS: We conclude that carotid endarterectomy without reversal of heparin anticoagulation is associated with a reduced postoperative stroke rate without a significant increase in morbidity rates.

Aged↗

PubMed1995

Anterior lung herniation: another aspect of the seatbelt syndrome.

Shoulder harnesses can be a source of thoracic injury in motor vehicle crashes. Sternal and rib fractures are most commonly reported. We present a case of a traumatic anterior lung herniation secondary to shoulder harness trauma in a motor vehicle crash victim with multiple injuries. A brief review of lung hernias is provided as well as a brief discussion of the thoracic manifestations of the seatbelt syndrome.

Accidents, Traffic↗

PubMed1995

Chemoprophylaxis of multidrug-resistant tuberculous infection in HIV-uninfected individuals using ciprofloxacin and pyrazinamide. A decision analysis.

STUDY OBJECTIVE: To evaluate the use of ciprofloxacin and pyrazinamide for the prophylaxis of individuals infected with multiply drug-resistant strains of Mycobacterium tuberculosis. DESIGN: Decision analysis, using software (SMLTREE). Probabilities based on published studies, with sensitivity analysis for each probability. SETTING: Health-care workers infected with multidrug-resistant strains of M tuberculosis. INTERVENTIONS: Prophylaxis with ciprofloxacin and pyrazinamide. MEASUREMENTS AND RESULTS: We calculated the utilities of taking or not taking prophylaxis with ciprofloxacin and pyrazinamide. The decision analysis favored the use of ciprofloxacin-pyrazinamide prophylaxis by a small margin. CONCLUSION: Ciprofloxacin-pyrazinamide prophylaxis should be considered for health-care workers infected with multiply drug-resistant M tuberculosis.

Adult↗

PubMed1994

Use of video-assisted thoracic surgery in the treatment of chylothorax.

Chylothorax, a potentially lethal disorder that may cause profound respiratory, nutritional, and immunologic complications, has become increasingly common in recent years. Medical therapy has been found to have a significant failure rate. Therefore, surgical treatment of complicated chylothorax has become a mainstay of care. Between 1987 and 1993, ten patients at the University of Virginia Hospital were treated with video-assisted thoracic surgery for complicated chylothorax. Twelve thoracoscopic procedures were performed. Patients ranged in age from 7 months to 82 years. Causes included iatrogenic (2), congenital (2), caval thrombosis (2), amyloid (2), blunt trauma (1), and metastatic carcinoid tumor (1). In 10 cases, video-assisted thoracic surgery was employed as the principal mode of therapy: 8 using talc pleurodesis alone, 1 using talc pleurodesis and clipping of the thoracic duct with application of fibrin glue, and 1 requiring clipping of a pleural defect with application of fibrin glue. In 2 cases, a video-assisted thoracic operation was used in conjunction with pleuroperitoneal shunting: a previously placed pleuroperitoneal shunt that was malfunctioning was repositioned thoracoscopically after a pleural adhesiolysis, and a pleural adhesiolysis was performed thoracoscopically before placement of a pleuroperitoneal shunt. In all cases the effusion resolved after the video-assisted thoracic operation without further intervention. Video-assisted thoracic surgery offers an effective means of treating chylothorax, regardless of cause, allowing the advantage of access to thoracic structures without the morbidity of more extensive procedures.

Adult↗

PubMed1994

Clinical evaluation of the diagnostic value of measuring IgG antibody to 3 mycobacterial antigen preparations in the capillary blood of children with tuberculosis and control subjects.

SETTING: Department of Paediatrics in a University Hospital. OBJECTIVE: To evaluate ABC-ELISA as serodiagnostic tests for tuberculosis in children. DESIGN: An avidin-biotin-peroxidase conjugated anti-human immunoglobulin (ABC) enzyme-linked immunosorbent assay (ELISA) was established to measure serum immunoglobulin G (IgG) antibodies to polymerized old tuberculin (OT), tuberculin purified protein derivative (PPD) and the 30,000 dalton (30 kDa) native antigen of Mycobacterium tuberculosis, in 122 tuberculosis patients and 187 healthy children. RESULTS: In those patients who had received less than 3 months of chemotherapy the sensitivities of the tests based on OT, PPD and the 30 kDa antigen were 40.3%, 50.0% and 36.1% respectively; the positive predictive values were 92.6%, 94.7% and 93.8% respectively and the negative predictive values were 58.6%, 62.9% and 57.2% respectively. CONCLUSION: The ABC-ELISA may be useful for the diagnosis of pulmonary and extrapulmonary tuberculosis in groups of children with a high prior probability of tuberculosis. Antibodies to the 30 kDa antigen persisted longer than did those to OT and PPD.

Age Factors↗

PubMed1994

Reduced sensitivity of tuberculosis serodiagnosis in patients with AIDS in Uganda.

SETTING: The diagnostic utility of serodiagnosis of tuberculosis in HIV-infected persons was studied in Kampala, Uganda. OBJECTIVE: This study was undertaken to evaluate the utility of a recently described serologic assay for the diagnosis of tuberculosis in HIV-infected patients. DESIGN: The study was undertaken as a cross-sectional survey of 349 subjects, including human immunodeficiency virus-infected and uninfected patients with tuberculosis and control subjects. Serum from each subject was assayed by enzyme-linked immunosorbent assay (ELISA) for IgG antibody to the 30,000 dalton antigen of Mycobacterium tuberculosis. RESULTS: Test sensitivity dropped from 0.62 in non HIV-infected tuberculous patients to 0.28 in HIV-infected patients. CONCLUSIONS: ELISA serodiagnosis of tuberculosis may have a markedly decreased utility in populations where HIV infection is prevalent.

AIDS-Related Opportunistic Infections↗

PubMed1993

Thoracoscopic diagnosis and treatment of mediastinal masses.

Evaluation of mediastinal masses often involves an array of imaging procedures and percutaneous biopsy techniques. Despite this, surgical intervention with an open biopsy is often required, especially to diagnose mediastinal malignancies. We report 22 patients with mediastinal masses who were managed with thoracoscopic biopsy, as opposed to open biopsy. All of these patients either had unsuccessful fine-needle aspiration or were unacceptable candidates for percutaneous aspiration. The patients ranged in age from 11 months to 67 years with a mean age of 17.2 +/- 3.6 years. Thoracoscopy provided an accurate tissue diagnosis in 19 of the 22 patients (86%) without need for an open diagnostic procedure. In 1 patient, histoplasmosis was suspected from the thoracoscopic biopsy, but open thoracotomy was needed for confirmation. Of the 19 patients with a positive tissue diagnosis, 3 patients had bronchogenic cysts that were completely resected by thoracoscopy. The mean duration of chest tube drainage was 2.3 +/- 0.2 days, and there were no complications or procedure-related deaths. The average length of hospitalization was 6.0 +/- 0.8 days. We believe that thoracoscopy is a safe, rapid, and effective modality for the diagnosis of mediastinal masses. Accurate tissue diagnoses are obtained in most patients without the need for additional procedures. In addition, we have demonstrated that complete excision of certain benign lesions during thoracoscopy is possible.

Adolescent↗

PubMed1993

Diagnostic thoracoscopy for pleural disease.

The most common use for diagnostic thoracoscopy in pleural disease is to clarify whether or not an effusion is malignant. General anesthesia with single-lung ventilation when combined with new endoscopic instrumentation produces a high diagnostic yield. These anesthetic and surgical techniques when used with talc pleurodesis yield a 90% success rate in treating benign and malignant pleural effusions.

Anesthesia, General↗

PubMed1993

Mycobacterium avium antigenuria in patients with AIDS and disseminated M. avium disease.

A 22,500-Da antigen apparently specific to Mycobacterium avium, Mycobacterium intracellulare, and Mycobacterium scrofulaceum has been identified by Western immunoblotting. By use of a dot immunoassay, this antigen was found in the urine of 64% of patients with AIDS and disseminated M. avium disease. It was not found in the urine of healthy control subjects. Detection of antigenuria might provide the basis for rapid diagnosis of M. avium disease in patients with AIDS.

Acquired Immunodeficiency Syndrome↗

PubMed1993

Successful transplantation of marginally acceptable thoracic organs.

OBJECTIVE: This study evaluates the efficacy of personally inspecting marginal thoracic organ donors to expand the donor pool. SUMMARY BACKGROUND DATA: The present donor criteria for heart and lung transplantation are very strict and result in exclusion of many potential thoracic organ donors. Due to a limited donor pool, 20-30% of patients die waiting for transplantation. METHODS: The authors have performed a prospective study of personally inspecting marginal donor organs that previously would have been rejected by standard donor criteria. RESULTS: Fourteen marginal hearts and eleven marginal lungs were inspected. All 14 marginal hearts and 10 of the marginal lungs were transplanted. All cardiac transplant patients did well. The mean ejection fraction of the donor hearts preoperatively was 39 +/- 11% (range 15-50%). Postoperatively, the ejection fraction of the donor hearts improved significantly to 55 +/- 3% (p < 0.002). Nine of the ten lung transplant patients did well and were operative survivors. Our donor pool expanded by 36% over the study period. CONCLUSIONS: The present donor criteria for heart and lung transplantation are too strict. Personal inspection of marginal thoracic donor organs will help to maximize donor utilization.

Heart↗