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John Thomas

Publications and source records attributed to John Thomas.

10 recordsLinked to original sources
PubMed2003

Effects of subantimicrobial-dose doxycycline in the treatment of moderate acne.

OBJECTIVE: To determine if treatment with subantimicrobial-dose (SD) doxycycline hyclate (20-mg tablets taken twice daily) improved clinical outcome, had any detectable effect on skin flora, led to overgrowth or colonization of skin by opportunistic pathogens, or resulted in an increase in antibiotic resistance by the surface skin microflora in patients with moderate acne compared with placebo. DESIGN: Multicenter, double-blind, randomized, placebo-controlled, parallel-group trial. SETTING: Two university-based clinics. SUBJECTS: Adults (N = 51) with moderate facial acne. INTERVENTIONS: Patients were randomized to receive SD doxycycline (Periostat; CollaGenex Pharmaceuticals Inc, Newtown, Pa) or placebo twice daily for 6 months. MAIN EFFICACY OUTCOMES: Primary: changes from baseline in numbers of inflammatory, noninflammatory, and total lesions. Secondary: changes from baseline of individual counts of papules, pustules, and nodules and global assessments of clinical improvement by patient and physician. RESULTS: Forty patients completed 6 months of treatment. At 6 months, the SD doxycycline group had a significantly greater percent reduction in the number of comedones (P<.01), inflammatory and noninflammatory lesions combined (P<.01), and total inflammatory lesions (P<.05) than did the placebo group. They also had significantly greater improvement according to the clinician's global assessment (P =.03). There were no significant differences in microbial counts between groups and no evidence of change in antibiotic susceptibility or colonization by potential pathogens. The treatment was well tolerated. CONCLUSIONS: Twice-daily SD doxycycline treatment significantly reduced the number of inflammatory and noninflammatory lesions in patients with moderate facial acne, was well tolerated, had no detectable antimicrobial effect on the skin flora, and did not result in any increase in the number or severity of resistant organisms.

Acne Vulgaris↗
PubMed2003

Results of surgical treatment for cerebral metastases.

Cerebral metastases are commonly encountered, with an incidence ranging from 20 to 30% of cancer cases. Medical and radiation therapy confer median survival ranging from 3 to 6 months only. A retrospective review of patients undergoing surgery with radiotherapy from January 1997 to January 2000 involved 26 patients (13 males, 13 females), with a mean age of 53.1 years (range 30-69 years). The mean follow-up was 15.8 months (range 1.5-27 months). The primary cancer was breast in nine cases, eight were lung cancers, six colonic cancers, two unknown primaries and one was a soft tissue sarcoma. Patients with extracranial secondaries numbered 17 (61.5%). Patients stayed on average for 15.4 days. No intracranial complications occurred postoperatively. No mortalities occurred in the first month and 11 patients (42.3%) were alive at 1 year. Two patients underwent a radiosurgical boost and six patients underwent adjuvant chemotherapy. Overall median survival was 9 months (95% confidence interval 7.3-12.9 months). Factors which may favour longer survival were female sex (median of 12 vs 6.1 months), younger patients (median of 12 vs 5.8 months) and breast cancer (median of 9 months). Surgical treatment appears beneficial, with subgroups such as breast cancer possibly doing better.

Adult↗
PubMed2003

Usefulness of sonographic guidance during percutaneous biopsy of mesenteric masses.

OBJECTIVE: The objective of our study was to determine the usefulness of sonographic guidance for biopsy of mesenteric masses. MATERIALS AND METHODS: Twenty-five sonographically guided percutaneous biopsies of mesenteric masses were performed in 23 patients. Biopsies were performed with an 18-, 20-, or 22-gauge self-aspirating needle or core biopsy device. Final pathology results and patient medical records were reviewed for biopsy accuracy and complications. A biopsy was considered successful if a specific benign or malignant diagnosis was rendered by the pathologist or if surgical-pathologic confirmation was obtained. RESULTS: Open surgical biopsy was performed after sonographically guided biopsy in 13 patients and led to 12 concordant diagnoses (nine true-positives and three true-negatives) and one discordant diagnosis (false-negative). Specific pathologic diagnosis was rendered for the 10 percutaneous biopsies that were not confirmed by surgical biopsy: five biopsies matched known primary malignancies, consistent with metastases; four biopsies revealed primary tumors, and one biopsy revealed chronic inflammation (nine true-positives and one true-negative). Two biopsies were nondiagnostic because of insufficient material (n = 1) and necrotic tumor (n = 1). In the biopsies with diagnostic tissue specimens, sonographically guided biopsy achieved a sensitivity of 95% (18/19) and specificity of 100% (4/4) for allowing neoplastic tissue to be distinguished from nonneoplastic tissue. Complications included a mesenteric hematoma and abdominal wall cellulitis. CONCLUSION: Percutaneous biopsy of mesenteric masses is a useful and safe procedure.

Adult↗
PubMed2002

Preoperative combined nested reverse transcriptase polymerase chain reaction for prostate-specific antigen and prostate-specific membrane antigen does not correlate with pathologic stage or biochemical failure in patients with localized prostate cancer undergoing radical prostatectomy.

PURPOSE: We report a prospective study examining the ability of preoperative nested reverse transcriptase polymerase chain reaction (RT-PCR) for prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSM) to predict pathologic stage and biochemical recurrence in patients with clinically localized prostate cancer treated with radical prostatectomy. PATIENTS AND METHODS: One hundred forty-one patients were entered onto the study. Preoperative evaluation included clinical T stage, serum PSA, biopsy Gleason score, and serum RT-PCR for PSA/PSM. Univariate and multivariate logistic regression models, Kaplan-Meier estimates, and Cox proportional hazards modeling were used to identify predictors of pathologic stage and biochemical failure. RESULTS: Seventy-three patients (51.8%) were RT-PCR positive for PSA, PSM, or both. In the multivariate logistic regression model, only initial PSA was an independent predictor of pathologic stage as defined by organ-confined disease (odds ratio [OR], 1.06; 95% confidence interval [CI], 1.00 to 1.13; P =.026) or organ-/specimen-confined disease (OR, 1.09; 95% CI, 1.02 to 1.16; P =.009). Overall Kaplan-Meier biochemical relapse-free survival (bRFS) was 85% at 59 months. Multivariate analysis of predictors for bRFS with the Cox proportional hazards model indicated that only initial PSA (OR, 1.05; 95% CI, 1.02 to 1.09; P =.004) and biopsy Gleason score (OR, 3.57; 95% CI, 1.37 to 9.58; P =.009) were independent predictors of biochemical failure. RT-PCR status did not predict pathologic stage or biochemical failure. Repeat analysis excluding 27 patients who received preoperative androgen-deprivation therapy did not change the results. CONCLUSION: Combined nested RT-PCR for PSA and PSM is not an independent predictor of pathologic stage or biochemical failure in patients with localized prostate cancer undergoing radical prostatectomy. This assay has no clinical utility in this patient population.

Antigens, Surface↗
PubMed2002

Management of stage I nonseminomatous germ-cell tumors.

Following orchiectomy in patients with stage 1 nonseminomatous germ-cell tumors (NSGCT), there are three treatment options. Retroperitoneal lymph-node dissection (RPLND) is currently the treatment of choice in the United States and can be both diagnostic and therapeutic but is associated with surgical morbidities. Surveillance is the least invasive but carries the highest potential for relapse and can be timely and costly for both patient and physician. Primary chemotherapy avoids the morbidity of surgery while achieving similar survival rates, albeit with potentially significant side effects. The advantages and disadvantages of each treatment modality are discussed.

Germinoma↗
PubMed2002

Anatomy of the intrinsic hand muscles revisited: part II. Lumbricals.

The authors discuss the anatomic variations and the precise origins and insertions of the lumbrical muscles, after dissecting 14 fresh cadavers (56 lumbrical muscles) and reviewing the scant published literature. They compare the findings with those of other investigators, and they describe the lumbrical muscle insertions discovered during the dissections. The authors conclude that descriptions of the origins and insertions of the lumbrical muscles have been oversimplified or not investigated at all, that lumbricals originate variably from the flexor digitorum profundus tendon and may even be bipinnate, and that three different major destinations exist for distal insertion of these intrinsic muscles: bone, volar plate, and extensor apparatus. Previous descriptions have focused only on the lumbrical continuation to the lateral band of the extensor mechanism.

Aged↗
PubMed2002

Mechanisms of mobilization of hematopoietic progenitors with granulocyte colony-stimulating factor.

Hematopoietic progenitor cells can be mobilized from the bone marrow to the blood by a wide variety of stimuli, including hematopoietic growth factors, chemotherapy, and chemokines. Increasingly, mobilized peripheral blood hematopoietic progenitor cells instead of bone marrow hematopoietic progenitor cells have been used to reconstitute hematopoiesis after myeloablative therapy because of their reduced engraftment times and relative ease of collection. A striking feature of hematopoietic progenitor cell mobilization is the ability of hematopoietic growth factors with distinct cellular targets and biologic activities to mobilize a similar spectrum of pluripotent and lineage-committed hematopoietic progenitor cells into the blood. Recent studies have identified some of the key adhesive interactions that regulate hematopoietic progenitor cell trafficking in the bone marrow. In addition, pathways linking mobilizing agents to hematopoietic progenitor cell mobilization have begun to be elucidated. This review summarizes these advances, emphasizing the mechanisms regulating granulocyte colony-stimulating factor-induced mobilization.

Animals↗
PubMed2002

Anatomy of the intrinsic hand muscles revisited: part I. Interossei.

In this article, the anatomic variations in interosseous muscle insertions are described based on a review of the literature and 14 fresh cadaver hand dissections. The findings are correlated and compared with those of a number of other investigators, and the clinical implications are discussed (i.e., in the correction of ulnar deviation in arthritis patients and in the treatment of congenital anomalies of the hand). It is concluded that descriptions of insertion sites of the intrinsic muscles have been oversimplified by previous researchers, and a number of variations are identified through the cadaver dissections. The differing and confusing nomenclature used by other investigators is discussed and simplified. The results of this study indicate that not only are there important distal insertions onto bone and the extensor apparatus, but there is also an additional insertion onto the volar plate ("assemblage nucleus"), as Zancolli reported. It was found that the palmar interossei, generally thought to insert only onto the extensor apparatus, could also insert onto bone and onto the volar plate. Classic teaching is that all dorsal interossei (except the third) have two heads and that all palmar interossei have only one head. In this study, however, 38 percent of the palmar interossei and 75 percent of the dorsal interossei had more than one head. The complexity of the interossei is apparent when as many as three different muscle heads are present, each with a different distal destination.

Aged↗