Biomedical subjects

M B Anderson

Publications and source records attributed to M B Anderson.

57 records · Page 4Linked to original sources

PubMedDate not supplied

Effects of cadmium cell viability, trophoblastic development, and expression of low density lipoprotein receptor transcripts in cultured human placental cells.

Previously, we have demonstrated that cadmium inhibits progesterone release in cultured human trophoblast cells. In the present study, we investigated potential mechanism(s) by which cadmium may elicit this effect. Cytotrophoblasts were obtained via enzymatic dispersion, purified by density gradient centrifugation, and cultured with increasing concentrations of cadmium. Cadmium-induced suppression of progesterone release seemed to be independent of cell death, as no significant decline in viability was observed with cadmium treatment. Further, immunocytochemical localization of cellular boundaries and nuclei indicated approximately 94% syncytial maturity was attained by both untreated and cadmium-treated cells, demonstrating that cadmium did not inhibit syncytial development. However, the abundance of LDL receptor (LDL-R) mRNA transcripts, as determined by competitive RT-PCR, was reduced (P < 0.05) by cadmium exposure in an apparent dose-dependent manner. Thus, the LDL-R, by which cholesterol substrate is supplied to the syncytiotrophoblast, is one site at which cadmium may interfere with placental progesterone production.

Apoptosis↗

PubMedDate not supplied

False positive cervicovaginal cytology. A follow-up study.

OBJECTIVE: To determine what percentage of cervical cytologic diagnoses initially classified as false positives (based on a negative cervical biopsy within three months of the cervical cytologic smear) are recategorized as histologic false negatives when subsequent studies reveal abnormalities. STUDY DESIGN: A three-year review of 1,242 cervicovaginal biopsies with corresponding cytology in the preceding three months revealed 68 cases (5.5%) where the cytology was positive for a squamous intraepithelial lesion but the biopsy was within normal limits or showed benign cellular changes. Follow-up cytologic and/or histologic diagnoses were obtained for 53 of the 68 cases from the patients' hospital and physician office records. RESULTS: Of the 53 cases with follow-up, 24 (45%) were found to have a subsequent squamous intraepithelial lesion (indicating a sampling error at the time of the initial biopsy), and 9 showed atypical squamous cells of undetermined significance. In addition, 9 of the 20 patients (45%) who had negative follow-up studies had benign abnormalities on the initial, noncorrelating biopsy that may have contributed to the discrepancy. CONCLUSION: This study emphasized the importance of diligent follow-up of patients with noncorrelating studies since they represent a population at high risk for the subsequent detection of premalignant conditions.

Biopsy↗

PubMedDate not supplied

Techniques for bronchial anastomosis.

BACKGROUND: Many techniques have been described to optimize the construction of the bronchial anastomosis in lung transplantation. Over the past 60 months we have performed 86 bronchial anastomoses in 70 patients receiving single lung or bilateral single lung transplants. METHODS: No anastomosis was wrapped and no attempt was made at revascularization of bronchial arteries. A continuous nonabsorbable suturing technique was used in all cases. Standard triple-drug immunotherapy with cyclosporine, azathioprine, and prednisone (starting at day 7) was used for each patient. RESULTS: There were no anastomotic leaks, and seven stenoses were identified in five patients (7%). All complications were managed conservatively with stenting, and there were no related deaths. Mean time to stent placement was 109 days. One patient had bilateral stents placed prophylactically during an episode of severe infection for questionable anastomotic viability but without evidence of airway necrosis or obstruction. This patient died of infection at 16 days. Another patient died with stents in place at 71 days. In the four remaining patients, all stents have been removed after a mean of 310 days. These patients were followed up with serial bronchoscopy and were without evidence of recurrent obstruction at 2, 34, 35, and 36 months. Six of seven stenoses occurred in patients with cystic fibrosis. In each patient where stenosis developed the anastomosis was telescoped. Since abandoning the telescoping technique in the remaining 50 anastomoses (14 in patients with cystic fibrosis), no dehiscence or stenosis was encountered. CONCLUSIONS: These data suggest that elaborate techniques aimed at construction of the bronchial anastomosis are not necessary. Moreover, attempts at telescoping may be detrimental. Patients with cystic fibrosis may be a population at higher risk for anastomotic complications. Airway complications can be managed conservatively with good results and little risk to the patient.

Adult↗