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T L Johnson

Publications and source records attributed to T L Johnson.

At least 37 records · Page 2Linked to original sources
PubMed1995

Update on the surgical pathology of the vulva.

Recent developments in the surgical pathology of the vulva include updated classifications of non-neoplastic epithelial disorders and vulvar intraepithelial neoplasias. Several histologic variants of vulvar squamous cell carcinoma (SCC) with distinct clinicopathologic features have been described. The concept of superficially invasive vulvar SCC continues to be a complex issue. The use of standardized surgical pathology reports and checklists are recent developments in surgical pathology.

Basal Cell Carcinoma↗
PubMed1994

Complexes of yeast RNA polymerase II and RNA are substrates for TFIIS-induced RNA cleavage.

In the absence of DNA, purified yeast RNA polymerase II can bind RNA to form a binary complex. RNA in such RNA-RNA polymerase complexes undergoes reactions previously thought to be unique to nascent RNA in ternary complexes with DNA, including TFIIS-dependent cleavage and elongation by 3'-terminal addition of NMP from NTP. Both of these reactions are inhibited by alpha-amanitin. Hence, by several criteria the RNA in binary complexes is bound to the polymerase in a manner quite similar to that in ternary complexes in which the catalytic site for nucleotide addition is positioned at or near the 3'-OH terminus of the RNA. These findings are consistent with a model for the RNA polymerase ternary complex in which the RNA is bound at the 3' terminus through two protein-binding sites located up to 10 nt apart.

Amanitins↗
PubMed1994

Prevalence of HPV 16 and 18 DNA sequences in CIN III lesions of adults and adolescents.

Adolescents may be more susceptible to cervical human papillomavirus (HPV) infections and may have more rapid progression of cervical intraepithelial neoplastic (CIN) lesions than adults. We evaluated Papanicolaou (Pap) smears and cervical tissue specimens from a consecutive series of 25 adolescent (age 15-20 yr) and 17 adult (age 35-40 yr) patients with a histologic diagnosis of CIN III. The study patients were all Detroit residents enrolled in a health maintenance organization (HMO) affiliated with Henry Ford Hospital. The cervical tissue specimens were evaluated for HPV 6b/11, HPV 16, and HPV 18 using agarose gel electrophoresis and Southern hybridization following polymerase chain reaction (PCR) DNA amplification. While the small sample size precluded testing for statistical significance, HPV 16 and/or HPV 18 DNA was detected in specimens from 21/25 (84%) adolescents compared to 12/17 (71%) adults (odds ratio [OR] = 2.2; 95% confidence interval [CI] = 0.49-9.74). The relationship between adolescence and HPV infections appears to be stronger for HPV 18 and mixed HPV 16/18 infections (OR = 5.6; 95% CI = 0.7-42.4) than for HPV 16 infections (OR = 1.93; 95% CI = 0.4-8.8). None of the cervical specimens contained HPV 6b/11 DNA. Oral contraceptive (OC) use was associated with HPV infection in patients with CIN III, but there was no association between cigarette smoking and HPV infection. The effect of OC use on the relationship of age and HPV could not be evaluated due to small sample size. The effects of previous sexually transmitted disease (STD) on the relationship of age and HPV were assessed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Diagnosis of low back pain, secondary to prostate metastasis to the lumbar spine, by digital rectal examination and serum prostate-specific antigen.

OBJECTIVE: To present a case in which the initial diagnosis of spinal metastasis secondary to prostate cancer was established from findings of the digital rectal examination (DRE) and serum prostate-specific antigen (PSA) analysis. CLINICAL FEATURES: A 79-yr-old black male was seen after suffering from low back pain for 1 month. Urinary frequency and nocturia were associated symptoms. Abnormal findings on the DRE and serum PSA determination suggested a preliminary diagnosis of spinal metastases secondary to prostate cancer. Subsequent referral for biopsy and bone scan yielded the final diagnosis of prostate adenocarcinoma with spinal metastasis. Radiographs of the lumbosacral spinal region were inconclusive and results of routine laboratory tests (CBC, ESR, U/A) were within normal limits. INTERVENTION AND OUTCOME: The patient was referred for medical palliation of his condition. A bilateral orchiectomy was performed along with oral antiandrogen administration. At a consultation 8 months postoperatively, he reported to be free of pain. CONCLUSION: At least 40% of newly diagnosed cases of prostate cancer can be expected to have metastasized at the time of initial discovery. Routine use of DRE and serum PSA in patients complaining of low back pain who are at high risk for prostate cancer is recommended. However, mass screening with DRE or PSA in asymptomatic males is not recommended. There are no prospective studies showing evidence that mass screening for prostate cancer will reduce the mortality or morbidity rates from the disease.

Adenocarcinoma↗
PubMed1993

Gentamicin toxicosis in a North American cougar.

This report documents nephrotoxicosis in a North American cougar (Felis concolor) caused by gentamicin overdose and describes a method of calculating drug dosages by metabolic scaling for species in which pharmacokinetic studies have not been performed. Determining drug dosages by metabolic scaling can decrease the likelihood of administering inappropriate drug doses in exotic animals.

Alopecia↗
PubMed1993

Cytologic features of metastatic transitional cell carcinoma.

Cytologic preparations containing metastatic transitional cell carcinoma (MTCC) from 18 sites in 16 patients were reviewed to determine characteristic morphologic features. The patient group included 13 males and 3 females with a mean age of 66 years. Primary TCC occurred in the bladder (14), kidney (1), and ureter (1); nearly all the primary tumors were poorly differentiated and most were invasive at the time of diagnosis. The cytologic specimens were derived from lymph nodes (6), liver (4), serous fluids (2), pelvic soft tissue (2), subcutaneous nodules (2), and lung (1). One patient presented with MTCC in Pap smears. Cytologically MTCC presented as loosely cohesive, moderate to markedly pleomorphic cells which occurred singly and in syncytial clusters. The malignant cells were usually large with abundant granular or fibrillar cytoplasm and the cell borders were generally distinct. Most nuclei were large and hyperchromatic with irregularly distributed granular chromatin and prominent nucleoli. The most distinctive features were the presence of spindled, pyramidal, and/or racquet-shaped malignant cells with eccentric nuclei and cytoplasmic features of both squamous and glandular differentiation including endoplasmic/ectoplasmic interfaces and intracytoplasmic vacuoles. Although clinical history is most useful in the diagnosis of MTCC, these morphologic features in cytologic preparations of malignant epithelial neoplasms may be helpful. In the absence of a known primary TCC, it is doubtful that a definite cytologic diagnosis could be made; however, the characteristic cell shapes and cytoplasmic features may be suggestive of MTCC.

Aged↗
PubMed1993

Worsening tricuspid regurgitation following pericardiectomy for constrictive pericarditis.

We describe two cases of worsening tricuspid regurgitation following surgical pericardiectomy for constrictive pericarditis. Both patients demonstrated hemodynamic profiles characteristic of constrictive pericarditis on cardiac catheterization. They also had moderate tricuspid regurgitation as judged by Doppler echocardiography. The worsening tricuspid regurgitation observed was a result of postoperative right ventricular dilatation. These cases demonstrate the importance of determining tricuspid valvular function in patients with constrictive pericarditis prior to pericardiectomy; however, the hemodynamic changes that result in worsening tricuspid regurgitation may not be present for weeks.

Aged↗
PubMed1992

Use of an implant for intraosseous infusion as supportive therapy for a Vietnamese pot-bellied pig with urethral obstruction caused by a polyp.

A Vietnamese pot-bellied pig with a urethral polyp was supported by total parenteral nutrition given through an intraosseous implant. Peripheral vascular access was difficult to establish and maintain in this anorectic pig, so a pediatric intraosseous implant was placed in the left tibia. Surgical repair of the urethra was not considered possible, and alternative techniques of a functional bypass were unacceptable to the owners, so euthanasia was elected. Histologic examination of the urethra revealed a polypoid structure believed to be similar to benign congenital polyps described in young boys.

Animals↗
PubMed1992

Effects of combining transforming growth factor beta and 1,25-dihydroxyvitamin D3 on differentiation of a human osteosarcoma (MG-63).

Transforming growth factor beta (TGF beta) and 1,25-dihydroxyvitamin D3 (1,25D3), when added simultaneously to a human osteosarcoma cell line, MG-63, induce alkaline phosphatase activity 40-70-fold over basal levels, 6-7-fold over 1,25D3 treatment alone, and 15-20-fold over TGF beta treatment alone. TGF beta and 1,25D3 synergistically increased alkaline phosphatase specific activity in both matrix vesicles and plasma membrane isolated from the cultures, but the specific activity was greater in and targeted to the matrix vesicle fraction. Inhibitor and cleavage studies proved that the enzymatic activity was liver/bone/kidney alkaline phosphatase. Preincubation of MG-63 cells with TGF beta for 30 min before addition of 1,25D3 was sufficient for maximal induction of enzyme activity. Messenger RNA for liver/bone/kidney alkaline phosphatase was increased 2.1-fold with TGF beta, 1.7-fold with 1,25D3, and 4.8-fold with the combination at 72 h. Human alkaline phosphatase protein as detected by radioimmunoassay was stimulated only 6.3-fold over control levels with the combination. This combination of factors was tested for their effect on production of three other osteoblast cell proteins: collagen type I, osteocalcin, and fibronectin. TGF beta inhibited 1,25D3-induced osteocalcin production, whereas both factors were additive for fibronectin and collagen type I production. TGF beta appears to modulate the differentiation effects of 1,25D3 on this human osteoblast-like cell and thereby retain the cell in a non-fully differentiated state.

Alkaline Phosphatase↗
PubMed1992

Detection of HPV 16/18 DNA in cervical adenocarcinoma using polymerase chain reaction (PCR) methodology.

Twenty-two tissue samples of primary adenocarcinoma (adenoCA) of the uterine cervix were evaluated for the presence of HPV 16/18 DNA using the polymerase chain reaction (PCR). PCR was used to specifically amplify the E6-E7 gene region of HPV 16/18 DNA. The amplification products were analyzed using gel electrophoresis and Southern dot blotting with 32p labeled type-specific oligonucleotide probes. HPV 18 DNA was identified in 13/22 (59%) and HPV 16 DNA was identified in 5/22 (23%) of the tumors. There were no tumors with mixed infections. In three patients, two different specimens were evaluated, and there was concordance of HPV typing. The presence of squamous carcinoma in situ, koilocytosis and younger patient age were associated with an increased incidence of HPV 16/18 DNA detection. HPV 16/18 DNA was not detected in six metastatic adenoCA to cervix (four endometrial, two ovarian). We conclude that HPV 16/18 DNA is present in a significant proportion of primary adenoCA of the cervix, and we have identified some clinicopathologic associations. The detection of HPV DNA may be useful in distinguishing primary from metastatic adenoCA of the cervix.

Adenocarcinoma↗
PubMed1992

Ulcer recurrence following duodenal ulcer healing with omeprazole, ranitidine, or placebo: a double-blind, multicenter, 6-month study. The Omeprazole Duodenal Ulcer Study Group.

The present study determined whether the rate of relapse of duodenal ulcer was reduced after ulcer healing with omeprazole compared with ranitidine or placebo. It was made up of a double-blind, randomized, controlled multiple-center trial set within the United States. Patients were candidates if their duodenal or pyloric channel ulcer successfully healed in one of two large multicenter U.S. trials; one compared omeprazole, 20 mg once daily, before breakfast with ranitidine, 150 mg twice daily, and the other compared the same dose of omeprazole with placebo. Two hundred forty (73.8%) of the 325 patients with complete ulcer healing within 4 weeks of starting therapy who were eligible to enter the follow-up study were enrolled. There was no intervention. Endoscopic assessment of ulcer status was performed at 2, 4, and 6 months and whenever patients had symptoms thought to represent return of an ulcer. The lifetable relapse rates for duodenal ulcer according to initial ulcer therapy with omeprazole, ranitidine, or placebo were 76.7% [95% confidence interval (CI), 64%-89.3%], 59.8% (95% CI, 47.8-71.7%), and 50.4% (95% CI, 15.7%-85.2%), respectively. These rates were not statistically significantly different. Seventeen percent of recurrent ulcers occurred at a site different from that of the original ulcer. It is concluded that despite the more rapid rate of duodenal ulcer healing with omeprazole therapy, the rate of ulcer relapse appears similar and independent of whether ulcer healing was accelerated with omeprazole or ranitidine.

Adult↗
PubMed1991

Tuberculous Addison's disease.

Addison's disease is a possible diagnosis in any patient who presents with weakness, weight loss, hyperpigmentation, hyponatremia, and hypotension. Laboratory findings, including depressed levels of cortisol and aldosterone, help to confirm the diagnosis. Computed tomography may reveal adrenal calcification and abnormal-sized adrenal glands. In most cases, autoimmune destruction of the adrenal cortex is the cause of Addison's disease; however, as in the patient described here, tuberculosis is a possible cause.

Addison Disease↗
PubMed1991

Cytologic and clinicopathologic features of abnormal nipple secretions: 225 cases.

A case review of 225 patients with abnormal breast nipple secretions (NS) was done to determine diagnostically useful clinical and cytologic features. The cytologic specimens and medical records from all patients and 45 concurrent breast biopsies were reviewed. Nipple discharge was attributed to fibrocystic disease (FCD) in 81 cases, physiologic disturbances in 62, papillomas in 18, ductal carcinoma (CA) in 5, miscellaneous benign disorders in 14, and unknown causes in 45. Although cytologic examination of NS was very specific in identifying malignancy, the sensitivity of cytology was low. Carcinoma was diagnosed or suspected cytologically in only three of the five CA cases, with no false-positive cytopathologic interpretations. Malignant NS were usually unilateral, hemorrhagic, mass-associated, and in older patients. Males with nipple discharge had a significantly higher incidence of breast cancer (two of nine; 22%) than women with abnormal NS (3 of 216; 1.5%). Papilloma NS were generally unilateral and hemorrhagic; FCD and physiologic NS were mostly serous or milky. Benign NS were not cytologically distinguishable. We conclude that cytologic examination of NS is a specific but insensitive method to identify underlying malignancy. Additional clinical features, including patient age, laterality and character of NS, and radiographic findings, were found to be diagnostically useful.

Adult↗
PubMed1991

Cytologic features of collagenous spherulosis of the breast.

Collagenous spherulosis is generally classified as a component of benign proliferative breast disease. Previous reports have described the histologic features of collagenous spherulosis, but we are unaware of cytologic descriptions of the condition. In this report, the cytologic features of collagenous spherulosis are described and the differential diagnosis is discussed.

Adult↗
PubMed1991

U.S. experience with omeprazole in duodenal ulcer. Multicenter double-blind comparative study with ranitidine. The Omeprazole DU Comparative Study Group.

To assess the comparative efficacy of omeprazole 20 mg, a proton pump inhibitor, versus ranitidine 150 mg twice a day, an H2-receptor antagonist, in healing duodenal ulcers we performed a randomized, double-blind, multicenter trial in 309 patients with endoscopically diagnosed ulcers. Patients were treated for up to four weeks and were seen at week 2 and at week 4, if unhealed at week 2, for determination of ulcer status by endoscopy, review of daily self-assessment symptom diaries, and clinical laboratory including fasting serum gastrin. Gastrin levels were repeated two weeks after cessation of study medication. Evaluation of baseline demographic and laboratory parameters demonstrated no significant differences between the two groups at entry. At week 2, 42% of the omeprazole and 34% of the ranitidine-treated patients were healed (P = NS). At week 4, there was a 19% advantage in ulcer healing for the omeprazole-treated patients in comparison to those treated with ranitidine (82% vs 63%, respectively, P less than 0.05). Healing of ulcers greater than or equal to 1.0 cm occurred in 83% of those treated with omeprazole versus 37% treated with ranitidine (P less than 0.01). There were no significant differences in rate of pain relief or incidence of clinical laboratory abnormalities. Mean fasting serum gastrin value during treatment increased over the baseline in both groups, (P less than 0.05). The percent change was significantly greater with omeprazole but few patients had elevations above the upper limit of normal for the assay. Both drugs were well tolerated. Omeprazole 20 mg demonstrated superiority in healing duodenal ulcers at four weeks in comparison to ranitidine 150 mg twice daily and was more effective in healing ulcers greater than or equal to 1.0 cm.

Double-Blind Method↗
PubMed1991

Chromosomal assignment in mouse of matrix Gla protein and bone Gla protein genes.

Matrix Gla protein (MGLAP) and bone Gla protein (BGLAP) are calcium-binding, vitamin K-dependent proteins produced by cells of the osteoblastic lineage. Sequence homology suggests that the genes for these proteins evolved from a common ancestor. Somatic whole cell hybrids and karyotypically simple microcell hybrids were used to map Mglap to mouse Chromosome 6 and Bglap to mouse Chromosome 3. Human MGLAP has previously been mapped to chromosome 12p, a region with homology to mouse Chromosome 6, and human BGLAP has been mapped to chromosome 1q, a region with homology to mouse Chromosome 3. It appears that BGLAP is the third calcium-binding protein that maps to human chromosome 1q and mouse Chromosome 3.

1-Carboxyglutamic Acid↗