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Poly(A) polymerase distribution in normal and malignant lymphoid cells.

The incorporation of ATP on poly(A) primers catalyzed by poly(A) polymerase was investigated in normal and neoplastic lymphoid cells from animal and human sources. High levels of the enzyme were found in mouse thymus, in chicken bursa and thymus, as well as in neoplastic cells from patients affected by lymphoblastic and Burkitt's lymphomas. Low or very low quantities were found in peripheral blood lymphocytes, chronic lymphocytic leukemia cells, normal lymph nodes and solid lymphoid tissues of Hodgkin's disease. In general, the enzymatic content of neoplastic lymphoid cells reflected those of their normal counterpart. No effect of fasting or cortisone treatment on poly(A) polymerase in mouse spleen, thymus or liver was found. No particular relationships with B, T or non-T, non-B lineages were observed, but some relationship with DNA polymerase alpha was found. Therefore, it may be that poly(A) polymerase levels are related to the proliferative activity of the cellular populations.

Animals↗

Assessment of Rorschach dependency measures in female inpatients diagnosed with borderline personality disorder.

The psychometric properties and predictive validity of the Dependency Index (DI; Hilsenroth & Bornstein, 2002) and the Rorschach Oral Dependency Scale (ROD; Masling, Rabie, & Blondheim, 1967) were examined to determine if these implicit measures of dependency predict observable attachment-seeking behavior in 66 female inpatients diagnosed with borderline personality disorder. Results indicate that both scales produce excellent reliability estimates. The DI and ROD yield adequate base rates, and the distributions of scores approximate normal distributions. The DI was predictive of nursing staff observation of positive attachment/treatment compliance (r = .28, p = .02) but not excessive isolation. By contrast, the ROD predicted positive attachment/treatment compliance (r = .38, p = .002) and excessive isolation (r = -.35, p = .004). Texture responses predicted excessive isolation (r = -.25, p = .05). Discriminant validity was supported when neither dependency measure predicted hostile interactions or self-destructive behaviors. Hierarchical regression analyses revealed that the ROD demonstrated incremental validity over the DI and select Comprehensive System (Exner, 1993) variables associated with dependency.

Adult↗

Corticotropin releasing factor distribution in normal and Brattleboro rat brain, and effect of deafferentation, hypophysectomy and steroid treatment in normal animals.

Corticotropin-Releasing Factor (CRF) activity was determined (dispersed pituitary cell assay) in rat median eminence (ME), various hypothalamic nuclei, as well as in entire median basal hypothalamus (MBH) and extra-hypothalamic areas. Highest concentrations were seen in ME, with decreased concentrations noted proceeding dorsally and cephalad from ME. Potency (NIAMDD HE-RP-1, ME reference extract, equivalent to 1.0) estimates were: ME-2.2; arcuate n.-0.88; dorsomedial n.-041; ventromedial n.-0.35; periventricular n.-0.24; hypothalamus-0.05; thalamus-0.01; cortex-0.005. Measurable, but lesser amounts, than in the above cited nuclei, were present in supraoptic and paraventricular nuclei. CRF activity was not measurable in preoptic area, septum, olfactory bulb, striatum, mesencephalon, pons, medulla or cerebellum. Complete hypothalamic deafferentation was accompanied by an increase in CRF activity/mug protein in ME and MBH, associated with decreased AM plasma ACTH and corticosterone concentrations. CRF-like activity in ME and MBH increased following hypophysectomy and after dexamethasone pretreatment. These findings indicate that CRF is mainly synthesized in the ME and surrounding area, and this source of CRF is sensitive to feedback effects and that extrahypothalamic inputs affect CRF release. Female animals had higher ME CRF content than did male animals. Homozygous and heterozygous Brattleboro rats had significantly less CRF in ME and MBH than did control animals, with significant differences also noted between homozygous and heterozygous animals.

Adrenal Cortex Hormones↗

Histochemistry and acetylcholine receptor distribution in normal and denervated monkey extraocular muscles.

In monkey extraocular muscles (EOM), a battery of histochemical reactions delineates three muscle fiber types, coarse, fine, and granular. Normal EOM are compared with EOM denervated by intracranial oculomotor nerve section. The experimentally denervated EOM fibers did not show the constellation of histologic responses typical of denervated limb muscle, making a diagnosis of a denervation process in EOM muscle very difficult. Although the denervated fine and granular fibers (but not the coarse fibers) develop diffuse extrajunctional acetylcholine receptors (AChR) following experimental denervation, this is not a reliable criterion of denervation because not all of those fibers developed it and they did not show it beyond a 12-week period following nerve section; moreover, myopathic mechanisms have previously been shown capable of provoking diffuse extrajunctional AChR in limb-muscle fibers.

Acetylcholine↗

Ascorbate induced changes in glycosaminoglycan synthesis and distribution of normal and SV40-transformed fibroblasts.

The effect of ascorbate on the glycosaminoglycans synthesized by normal and simian virus 40(SV40)-transformed human skin fibroblasts was examined. Cells were incubated in the presence or absence of ascorbate, and radiolabelled with [3H]glucosamine and [35S]sulphate for 48 h, 3 days after reaching confluence. Glycosaminoglycans were analysed in the medium, a collagenase extract, and in the trypsin/cell-associated fraction. Hyaluronic acid was the main 3H-labelled glycosaminoglycan in all but the collagenase extracts, and showed a large decrease in normal fibroblast cultures, but a significant increase in SV40-transformed fibroblast cultures following feeding with ascorbate. Incorporation of [3H]glucosamine into sulphated glycosaminoglycans was reduced in normal fibroblast cultures but increased slightly in SV40-transformed cultures following ascorbate supplementation. [35S]sulphate incorporation remained essentially unaltered in both cell cultures. Ascorbate stimulated the deposition of glycosaminoglycans into the insoluble matrix of normal fibroblasts while reducing the deposition in SV40-transformed fibroblast cultures. The observed changes may in part be related to ascorbate-induced deposition of collagen in normal fibroblast cultures and the inability of the transformed fibroblast cells to deposit an extensive extracellular matrix, in addition to possible changes in the specific activity of the UDP-N-acetyl-[3H]hexosamine pool.

Ascorbic Acid↗

Estimating population or group sensitivity and its precision from a set of individual d'.

A commonly used method of estimating population sensitivity is the so-called averaged d' method. In this method, the arithmetic mean of a set of individual d' is usually taken as a population sensitivity estimator. This practice ignores the fact that the individual d' itself is an estimator with an inherent variance. For observations with different levels of precision, the arithmetic mean is not the best estimator of a population parameter. It may lead to an estimate with a large variation. Another fact, which is often ignored, is that the variance of individual d' involves both between- and within-subject variations in a random effects model when population sensitivity and its level of precision are estimated. Failing to account for both components of variance leads to an underestimate of variation and an overestimate of precision for the estimator. In this paper a lognormal distribution rather than a normal distribution is assumed for individual sensitivity. An iterative weighting procedure is proposed for estimating population sensitivity on the log scale on the basis of a random effects model. An ordinary weighting procedure is proposed for estimating group sensitivity on the log scale on the basis of a fixed effects model. The levels of precision of population and group sensitivity estimators are also given. Numerical examples illustrate the estimation procedures.

Behavioral Research↗

Changes in in vivo optical properties and light distributions in normal canine prostate during photodynamic therapy.

The optical absorption and transport scattering coefficients of normal prostate tissue have been measured in vivo in dogs. The measurements were made at 630 nm before and during treatment by Photofin photodynamic therapy using interstitial optical fiber fluence-rate detectors. Corresponding measurements were made ex vivo, at 1 week after treatment, in the contralateral lobe. The optical properties were derived by applying a diffusion theory model to the fluence rates measured at two different source-detector fiber distances. While the in vivo pretreatment and in vivo contralateral post-treatment absorption and scattering values are self-consistent and in agreement with published data, significant changes were observed in the light fluence rates, and hence in the derived optical properties, during light irradiation. The possible causes of such changes are considered, and the implications for light dosimetry in photodynamic therapy are discussed.

Animals↗

Home storage temperatures and consumer handling of refrigerated foods in Sweden.

The lack of data on consumer refrigeration temperatures and storage times limits our ability to assess and manage risks associated with microbial hazards. This study addressed these limitations by collecting data on temperatures and storage handling practices of chilled foods. Consumers from 102 households in Uppsala, Sweden, were instructed to purchase seven food items (minced meat, fresh herring fillets, soft cheese, milk, sliced cooked ham, vacuum-packed smoked salmon, and ready-to-eat salad) and to store them using their normal practices. They were interviewed the next day, and food temperatures were measured. In general, there were no significant relations between temperature and characteristics of the respondents (e.g., sex, age, education, age of the refrigerator). Mean storage temperatures ranged from 6.2 degrees C for minced meat to 7.4 degrees C for ready-to-eat salad. Maximum temperatures ranged from 11.3 to 18.2 degrees C. Data were not significantly different from a normal distribution, except for ready-to-eat salad, although distributions other than the normal fitted data better in most cases. Five percent to 20% of the food items were stored at temperatures above 10 degrees C. Most respondents knew the recommended maximum temperature, but less than one fourth claimed to know the temperature in their own refrigerator. Practical considerations usually determined where food was stored. For products with a long shelf life, stated storage times were different for opened and unopened packages. The current situation might be improved if consumers could be persuaded to use a thermometer to keep track of refrigerator temperature.

Adult↗

Immunohistochemistry of CA 125. Unusual expression in normal tissues, distribution in the human fetus and questions around its application in diagnostic pathology.

CA 125 is known as the marker that is most strongly associated with epithelial gynecological tumors. Compared to the number of publications on its use in serum assays, the application in immunohistochemistry is still limited. The availability of many good antibodies that perform well in formalin-fixed paraffin-embedded tissue opens good possibilities for a wider use. Outside the gynecological tract several other structures may react positive for CA 125. Among these are the lung and breast but also the epithelial cells of the conjunctiva and to some extent prostate glandular epithelium. In the fetus reactions can be found in the serosal linings of body cavities but also in the esophagus and skin. In diagnostic pathology CA 125 plays a role in identifying the primary locations of metastatic carcinoma of unknown origin. It is recommended to use CA 125 antibodies not in a solitary setting but in combination with CEA, BRST-2 and Vimentin to discriminate best between the most frequent sites of origin of metastatic carcinoma. Regular analysis of sensitivity/specificity ratios in a balanced population, representing the composition of the patient population seen in daily practice, should be performed to evaluate the position of CA 125 in diagnostic immunohistochemistry.

CA-125 Antigen↗

Implications of nonuniform tumor doses for radioimmunotherapy.

UNLABELLED: This article describes a method of assessing the biologic consequences of nonuniform dose distributions produced in tumors by biologically targeted radionuclide therapy. The analysis is based on a simple mathematical model that assumes all tumor cells are uniformly radiosensitive. METHODS: Using the linear-quadratic radiobiologic model, it is possible to represent an absorbed dose distribution by a biologically effective dose (BED) volume histogram (BVH). The Laplace transform of the BVH yields an equivalent uniform biologically effective dose. This is a one-number value that fully describes the biologic effect of a nonuniform absorbed dose distribution. In this article, for the purposes of exposition, nonuniform BED distributions are represented by normal distributions. RESULTS: Nonuniform absorbed dose distributions are inefficient in sterilizing tumors and become proportionately less effective as the mean dose increases. The loss in effectiveness is most severe for radiosensitive tumors. CONCLUSION: Several approaches may alleviate the consequences of dosimetric nonuniformity. These include the use of smaller targeting molecules, radionuclides with longer emission ranges, fractionated administration of biologically targeted radionuclide therapy and combined modality treatments.

Drug Administration Schedule↗