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Biomedical subjects

W A Turner

Publications and source records attributed to W A Turner.

At least 19 recordsLinked to original sources
PubMed1995

The effect of relative humidity on mouse allergen levels in an environmentally controlled mouse room.

To determine the effect of humidity on the levels of the mouse allergen Mus m 1, an experimental animal room was constructed to control environmental variables. The sex, strain, age, and number of mice was constant in the room, so that the average daily production of Mus m 1 would not vary greatly. Six different levels of relative humidity from 15% to 65% were maintained for a minimum of a week each. Daily collections of airborne particulates were eluted from filters and Mus m 1 content measured by immunological assay. Increasing relative humidity caused a decrease in Mus m 1 levels from a high of 3 ng/m3 at 15% humidity to a low of 0.5 ng/m3 at 65% humidity. Thus, reduction of airborne allergen levels can be achieved by careful attention to humidity control, especially during the winter heating season when humidity levels may be low. This experimental room can be used to measure the effect of other variables such as ventilation rate, caging, bedding, and work practices on the levels of mouse allergen in an animal facility.

Allergens↗
PubMed1986

Cytosol estrogen receptor content of female parietal peritoneum.

The ovarian and peritoneal mesothelium are believed to derive from the same embryonal coelomic epithelium. Neoplastic proliferation of these epithelia is sometimes grossly and histologically similar. Recently estrogen receptors have been identified in gynecologic neoplasms. With the use of standard techniques, the parietal peritoneum was assessed for estrogen receptor content in 17 women undergoing celiotomy for various reasons. All peritoneal specimens were negative for estrogen receptor content. This suggests a heterogeneous origin of the peritoneal surface epithelium and that peritoneum may not be müllerian in origin.

Chromatography, Paper↗
PubMed1986

Neuroendocrine carcinoma of the uterine cervix complicated by pregnancy: case report and review of the literature.

A case report of neuroendocrine carcinoma of the cervix complicating pregnancy is presented. This represents the fourth reported case. Clinical staging was FIGO IB, and treatment consisted of radical surgery and aggressive chemotherapy. Electron microscopy confirmed the diagnosis of neuroendocrine carcinoma. The pregnancy-associated cases and a review of neuroendocrine cervical carcinoma are discussed.

Adult↗
PubMed1986

Detection and quantitation of fetomaternal hemorrhage.

Failure to administer additional doses of Rh immune globulin (RhIG) to patients with excessive fetomaternal hemorrhage (FMH) is one of the causes of continued Rh isoimmunization. We compared the fetal cell ratio (FCR) with the other laboratory methods currently used at our hospital to quantitate FMH, ie, fetal cell preparation (FCP), RhIG cross-match with maternal serum, and indirect Coombs' testing 24 to 48 hours after administration of RhIG. The incidence of excessive FMH as detected by the various methods was 3.6% (cross-match), 9.6% (Coombs'), 18% (FCP), and 66% (FCR). The methods currently used do not accurately quantify FMH. The FCR is the most sensitive test but it has a high false-positive rate and thus does not appear to be clinically useful. We suggest that repeating the indirect Coombs' test may provide a practical alternative for determining the need for additional doses of RhIG.

Adolescent↗
PubMed1982

Cathepsin B activity in B16 melanoma cells: a possible marker for metastatic potential.

In solid s.c. tumors of a variant of the murine B16 melanoma with high metastatic potential (B16F10), there was a 2- to 7-fold elevation of lysosomal cathepsin B activity when compared to the B16F1 variant with low metastatic potential. The highest activities (based on either protein or DNA) of cathepsin B were found in tumors of less than 1 g. When B16F1 and B16F10 melanoma variants were grown in tissue culture, the metastatic differential in cathepsin B activity was lost as the cells were subcultured. However, this differential in cathepsin B activity could be restored by reestablishing the cultured cells as s.c. tumors. The activities of four other lysosomal enzymes (cathepsin D, beta-N-acetylglucosaminidase, beta-glucuronidase, and acid phosphatase) showed little evidence of a positive correlation with the metastatic potential of the B16 melanoma variants. Eighty to 90% of cathepsin B activity has been localized to a fraction containing viable tumor cells which was isolated by centrifugal elutriation. In contrast, only 50% of cathepsin D activity was in the viable tumor cell fraction, and from 30 to 70% of beta-N-acetylglucosaminidase, beta-glucuronidase, and acid phosphatase. Elevated levels of cathepsin B in the high metastatic B16F10 variant are consistent with the idea that cathepsin B may play a direct or a regulatory role in tumor metastasis.

Acetylglucosaminidase↗
PubMed1981

Respiratory disease in Utah coal miners.

Two hundred forty-two Utah underground coal miners volunteered to participate in a respiratory disease study. They were an older group (mean, 56 years of age) and had spent a mean of 29 years in the coal-mining industry. The prevalence of chronic bronchitis was 57%, and that of coal worker's pneumoconiosis, 25%; only one worker had progressive massive fibrosis. Significant impairment of pulmonary function was found among those with a history of cigarette smoking. Chronic bronchitis or coal worker's penumoconiosis among nonsmokers did not impair pulmonary function. There was a significant association among the nonsmokers between increasing exposure to coal dust and coal worker's pneumoconiosis, but not for changes in pulmonary function. Coal mine dust had a significant influence in causing the symptom complex of chronic cough and sputum production, and coal worker's pneumoconiosis.

Bronchitis↗
PubMed1981

A course in electronics and instrumentation.

In response to the continued development of electronic instrumentation in all disciplines of clinical laboratory science, we have designed a new format for teaching electronic instrumentation. This course provides basic concepts in electronics, including safety precautions, the use of electronic testing equipment, methods for determining precision and accuracy of instruments, interpretation of the operating manual, and preventive maintenance. Students apply concepts by actually maintaining and adjusting improperly functioning instruments, using systematic techniques for trouble-shooting and adjustment. Student examinations indicate that the objectives are being met.

Electronics, Medical↗
PubMed1979

Common origin of pigment cells.

The fundamentally diverse vertebrate pigment cells, melanophores, xanthophores, and iridophores, contain pigmentary organelles known, respectively, as melanosomes, pterinosomes, and reflecting platelets. Their pigments are mealanins pteridines, and purines. Mosaic pigment cells containing more than one type of organelle have been observed and mosaic organelles containing more than one type of pigment have been discovered. It is proposed that the various pigment cells are derived from a stem cell that contains a primordial organelle of endoplasmic reticular origin. This primordial organelle can differentiate into any of the known pigmentary organelles.

Animals↗
PubMed1978

The effects of lumicolchicine, colchicine and vinblastine on pigment migration in fish chromatophores.

The effects of lumicolchicine, colchicine, vinblastine and cold temperature on the pigment migration in melanophores and xanthophores of Fundulus heteroclitus and Oryzias latipes were examined by light and electron microscopy. Xanthophores of both species which contain numerous microfilaments and a poorly developed microtubule system were extremely sensitive to the alkaloids. Lumicolchicine and colchicine induced irreversible dispersion while vinblastine caused permanent aggregation of the pigments. Treatment in lumicolchicine or colchicine at 5 mM for 60 minutes did not disrupt microtubules of melanophores to an appreciable degree, however, melanosome aggregation was partially inhibited by these drug in Oryzias. When melanophores were kept in the cold in the presence of colchicine at 1 mM, almost all microtubules were disrupted and their repolymerization at room temperature was nearly completely inhibited by colchicine. These melanophores lacking in microtubules responded to epinephrine with slow aggregation. Vinblastine at 0.1 mM induced partial aggregation of melanosomes and disruption of microtubules but most melanophores were still able to respond with pigment migration. Vinblastine at 1 mM made all melanophores punctate and immobile. Large vinblastine-induced crystals were frequently seen in the dendritic processes. The results of the present investigation suggest that cytoplasmic microtubules in fish melanophores facilitate melanosome migration only in directional orientation and appear not be responsible for the motive force.

Animals↗
PubMed1978

Synthesis of diastereoisomeric 4-dimethylamino-3-phenyl-2-butanols and related esters for antimicrobial evaluation.

4-Dimethylamino-3-phenyl-2-butanone was reduced to the corresponding diastereoisomeric alcohols, which were separated by fractional crystallization of the corresponding hydrochloride salts. The configuration of the diastereoisomeric alcohols was determined by PMR spectroscopy. The assignments were confirmed by a consideration of the mass spectral data obtained for the two alcohols. Acylation of the alcohols gave the corresponding esters. Antimicrobial evaluation of the compounds prepared showed that 4-dimethylamino-3-phenyl-2-butanone had a promising level of antifungal activity while the other derivatives showed either a low level of potency or were inactive.

Anti-Bacterial Agents↗
PubMed1977

Trysinase positive oculocutaneous albinism in the goldfish, Carassius auratus l., and ultrastructural and biochemical study of the eye.

Ultrastructural studies, and cytochemical and biochemical determinations of tyrosinase activity were conducted on the pigment epithelium of albino and xanthic goldfish eyes. In eyes of xanthic goldfish, two types of melanosomes are present, spherical and elongated. Melanized melanosomes are absent in the eyes of the albino goldfish, but elongated lamellar premelanosomes are observed. Internal vesicles are present in both melanosome types in the pigment epithelium of the xanthic goldfish but are absent in premelanosomes of the albino. There are also differences in the distribution of lipid droplets, smooth endoplasmic reticulum and Golgi complexes with the latter two being more abundant in the albino. Tyrosinase was not identified cytochemically; however, the enzyme was demonstrated biochemically in the pigment epithelia of both albino and xanthic goldfish. The enzyme is associated with the particulate and soluble fractions fo both types of eyes. Particulate albino tyrosinase may be solubilized by triton X-100 treatment. Tyrosinase inhibitors are present in the particulate fractions of both albino and xanthic goldfish eyes. Thus, in the goldfish, ocular albinism appears to be a multiple defect at the molecular and ultrastructural levels.

Albinism↗