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A Weller

Publications and source records attributed to A Weller.

At least 73 records · Page 4Linked to original sources
PubMed1995

Menstrual synchrony: only in roommates who are close friends?

This study examined menstrual synchrony among roommates residing in 20 university housing units. Menstrual synchrony was examined for roommates who were close friends and roommates who were not close friends, and by housing unit. The impact of personality, social-interaction and menstrual-related factors was also studied. To avoid limitations found in previous studies, (i) data were collected prospectively and (ii) over the entire academic year; (iii) high participation rate was obtained (86%); and (iv) women who used oral contraceptives were excluded. Menstrual synchrony was found among roommates who were close friends. Synchrony was not found for roommates who were not close friends, nor by housing units. The phenomenon of menstrual synchrony may more likely occur among close friends and women with intensive social contact than under the conditions common to university dormitories.

Adolescent↗
PubMed1995

Somatostatin levels during infancy, pregnancy, and lactation: a review.

This paper reviews research on somatostatin (SS) levels during infancy, pregnancy, and lactation. Neonates have elevated levels of circulating SS, which reach a peak at the age of 3 months and then decrease gradually, but remain elevated during the first years of life. SS response to feeding is not well developed in newborns. Elevated levels are also found during pregnancy, especially during the late phases. Influence of sucking on maternal SS plasma levels is varied and could be related to vagal stimulation. pH levels, and basal SS levels. SS has been found in high concentrations in maternal milk. Milk-borne SS appears to be protected from proteolysis by milk components, but apparently SS is not absorbed in its intact form through the duodenal wall and its effects could be indirect. More research is needed to determine the regulating role of milk-borne SS and the contribution of SS to development.

Breast Feeding↗
PubMed1995

Menstrual synchrony: agenda for future research.

While many studies have confirmed McClintock's (1971) finding of human menstrual synchrony, it is also clear that menstrual synchrony does not always occur. To better understand the mechanisms and functions of this phenomenon, this paper suggests directions for future research aimed at delineating the context and conditions under which menstrual synchrony occurs. It is proposed that the following research issues be explored: multiple sources of social influence; quality of social relationships; analyzing couple (or group) data; who synchronizes to whom?; group size; putative pheromones; age and age diversity; and contraceptive practices.

Adult↗
PubMed1995

The impact of social interaction factors on menstrual synchrony in the workplace.

The two objectives of this study were: (1) to examine the impact of social interaction variables (e.g., friendship, time working together, and activity) on the occurrence of menstrual synchrony; (2) to examine the menstrual synchrony of women who work together in an office. The sample consisted of 72 women soldiers in two army bases, and a civilian sample of 36 office workers. None of the samples showed significant synchrony. However, social interaction variables were found to be important factors contributing to the relative degree of synchrony. Friendship, mutual activity, and length of time working together were significantly related to the degree of synchrony.

Adolescent↗
PubMed1995

Examination of menstrual synchrony among women basketball players.

Based on the hypothesis that olfactory communication may underlie menstrual synchrony, we examined menstrual synchrony among eight professional basketball teams in the Israeli womens' major basketball league. We investigated whether team synchrony occurred, whether best friends among the teammates synchronized, and whether menstrual-related or social-interaction factors were associated with synchrony. Synchrony was not found among the teams nor among best friends. No meaningful relation was found between synchrony and menstrual-related or social-interaction variables.

Adolescent↗
PubMed1995

Cellular immune activity in response to increased training of elite oarsmen prior to Olympic competition.

This study investigated the changes in urinary neopterin, a biochemical marker of cellular immune activity, in elite male rowers undertaking a progressive increase in training prior to Olympic competition. Twenty-seven male rowers of the 1992 Great Britain team provided daily urine samples for a 4-week period of training that included 17 days of altitude training and 10 days of heat acclimatization. The mean (+/- S.D.) ratio of neopterin/creatinine in urine increased from pre-training values of 135 +/- 32 to a peak of 219 +/- 121 mumol neopterin per mol creatinine on day 19 of training (P < 0.05). Changes in the ratio of neopterin/creatinine with training were found to be transient and highly variable between subjects, ranging from no change to peak values five-fold greater than baseline. On the basis of the in vivo measurement of cell-mediated immunity employed in this study, we conclude that elite athletes engaged in high-intensity training prior to competition show either no change or a moderate increase in cellular immune activation.

Adult↗
PubMed1995

A simple model for studying the correction of in utero hypothyroidism in the rat.

Although the placenta is only a limited barrier for the transfer of thyroxine (T4) to the fetus, we have recently demonstrated that maternal T4 does not suffice to prevent the effects of in utero hypothyroidism. The current study presents a convenient and minimally invasive animal model to study whether maternal-fetal transfer of T4 administered to the pregnant rat corrects the newborn's in utero hypothyroidism. In this model pregnant rats receive the goitrogen methimazole in their drinking water from d 10 of gestation until birth, either alone or together with L-T4. Circulating T4 levels in the dams and newborn pups are measured from blood spotted on filter paper by RIA. Using blood T4 levels as the measure, in the present study we found similar effects for orally and intraperitoneally administered T4. This rat model will allow future studies of whether maternal-fetal T4 transfer can correct the detrimental neurobehavioral effects of intrauterine hypothyroidism.

Administration, Oral↗
PubMed1995

Regulation of mesenchymal extracellular matrix protein synthesis by transforming growth factor-beta and glucocorticoids in tumor stroma.

We have here studied the composition and regulation of stromal extracellular matrix components in an experimental tumor model. Nude mice were inoculated with WCCS-1 cells, a human Wilms' tumor cell line. In the formed tumors the stroma was found to contain mesenchymal extracellular matrix proteins such as tenascin-C, fibulins-1 and 2 and fibronectin, but no nidogen. Nidogen was confined to basement membranes of tumor blood vessels. Since glucocorticoids have been shown to downregulate tenascin-C expression in vitro, we tested whether dexamethasone can influence biosynthesis of extracellular matrix components during tumor formation in vivo. A downregulation of tenascin-C mRNA and an upregulation of fibronectin mRNA expression by dexamethasone was noted. Transforming growth factor-beta 1 mRNA levels were unaffected by the dexamethasone treatment. Glucocorticoids can thus downregulate tenascin-C synthesis although local stimulatory growth factors are present. The competition between a negative and a positive extrinsic factor on synthesis of stromal extracellular matrix components was studied in a fibroblast/preadipocyte cell line. Transforming growth factor-beta 1 stimulated tenascin-C synthesis but did not affect fibronectin or fibulin-2 synthesis. Dexamethasone at high concentrations could completely suppress the effect of transforming growth factor-beta 1 on tenascin-C mRNA expression. Transforming growth factor-beta 1 could in turn overcome the downregulation of tenascin-C mRNA expression caused by a lower concentration of dexamethasone. We therefore suggest that the limited expression of tenascin-C in part is due to a continuous suppression by physiological levels of glucocorticoids, which can be overcome by local stimulatory growth factors when present in sufficient amounts.

Animals↗
PubMed1994

Learned changes in the rate of respiratory pumping in Aplysia fasciata in response to increases and decreases in seawater concentration.

In Aplysia fasciata, the sea hare, shock paired with moderate increases or decreases in the seawater concentration leads to pairing-specific increases in the respiratory pump rate in response to the same solutions an hour later. A common neural circuit underlies learned changes to increased and decreased seawater concentration, as shown by complete generalization of learning between these stimuli. Different neural circuitry controls learning after pairing a shock with pH 7 seawater, as shown by a lack of generalization of learning to this stimulus. Preexposure to strong changes in the seawater leads to sensitization of respiratory pumping. The hypothesis was tested that associative learning and sensitization arise from activation of common pathways. However, patterns of generalization of sensitization elicited by preexposure to altered seawaters differ from those produced by associative learning.

Animals↗
PubMed1993

Menstrual synchrony between mothers and daughters and between roommates.

Menstrual synchrony was examined in three groups of women: 1) mothers and their daughters; 2) women sharing a room in a private residence; and 3) women sharing a room in a dormitory. The intracouple difference in menstrual onset dates was the dependent measure. Mothers and daughters living in the same domicile displayed a significant degree of synchrony. Roommates in private residences were also synchronous, although not significantly more than roommates residing in dormitories.

Adolescent↗
PubMed1993

Human menstrual synchrony: a critical assessment/.

This review on menstrual synchrony in human females has four purposes: (a) to determine whether or not the phenomenon exists, and whether it differs in the various groups studied: roommates in dormitories, roommates in private residences, close friends, work groups, mothers-daughters; (b) to assess the magnitude of its effect, i.e., to what extent does the single factor of living together affect menstrual synchrony?; (c) to examine the effects of menstrual-related factors, social interaction factors, and personality on menstrual synchrony; (d) to assess whether the findings support a pheromonal or common environmental explanation of menstrual synchrony. Several methodological issues are also discussed.

Bias↗
PubMed1993

Attachment styles, coping strategies, and posttraumatic psychological distress: the impact of the Gulf War in Israel.

This study examines the association between adult attachment style and the way people reacted to the Iraqi missile attack on Israel during the Gulf War. One hundred forty Israeli students were interviewed 2 weeks after the war and classified according to their attachment style (secure, avoidant, or ambivalent) and residence area (dangerous vs. less dangerous). Ambivalent people reported more distress than secure people. Avoidant persons reported higher levels of somatization, hostility, and trauma-related avoidance than secure persons. These results characterized Ss living in dangerous areas. In addition, secure people used relatively more support-seeking strategies in coping with the trauma, ambivalent people used more emotion-focused strategies, and avoidant people used more distancing strategies. Findings are discussed in terms of attachment working models.

Adaptation, Psychological↗
PubMed1993

Invasiveness of medical procedures and state anxiety in women.

The authors studied state anxiety in women awaiting three different medical examinations: abdominal ultrasonography, mammography, and hysterosalpingography. These procedures differ in degree of intrusiveness and cause, respectively, low, intermediate, and high levels of pain and discomfort. The evidence supported the hypothesis that the degree of anxiety will correspond to the level of invasiveness. In addition, the study examined the impact of demographic variables on degree of anxiety. The results suggest that to plan appropriate strategies for stress reduction, the medical team treating women should be aware of the degree of the procedure's invasiveness.

Adult↗
PubMed1992

Cloning of the mouse endothelial selectins. Expression of both E- and P-selectin is inducible by tumor necrosis factor alpha.

E-selectin (ELAM-1) and P-selectin (GMP-140, PADGEM, CD62) have both been described as human endothelial cell adhesion molecules for neutrophils and monocytes. Cell surface appearance of these two proteins on human umbilical vein endothelial cells can be regulated by different mechanisms: E-selectin is transcriptionally induced, within hours, by tumor necrosis factor alpha (TNF-alpha) while P-selectin is transported from storage granules to the plasma membrane within minutes upon induction by various stimulating agents. We have obtained cDNA clones covering the full-length coding sequence of the homologous mouse proteins for both endothelial selectins. We show that synthesis of mouse P-selectin, like that of E-selectin, is transiently induced by TNF-alpha in several endothelioma cell lines derived from different mouse tissues. This induction was monitored on both the RNA as well as the protein level. The TNF induced, newly synthesized P-selectin protein was detected on the cell surface. Protein expression of P-selectin increased with a slightly lower rate than expression of E-selectin. In organ cultures of lung tissue from TNF-injected mice, the synthesis of P-selectin was clearly elevated compared to control mice. The bovine P-selectin homolog recognized by cross-reaction with anti-mouse P-selectin antibodies was also TNF-inducible in primary capillary endothelial cells from adrenal cortex and in aorta-derived endothelial cells. Thus, P-selectin can be regulated on two different levels. While the transport of stored P-selectin to the cell surface is controlled by regulated secretion of storage granules, the synthesis and surface expression can be induced by TNF-alpha similarly to that of E-selectin.

Amino Acid Sequence↗
PubMed1992

Plastic surgery on children with Down syndrome: parents' perceptions of physical, personal, and social functioning.

Plastic facial surgery is being carried out on children with Down syndrome with the objective of improving these children's physical, personal, and social functioning. This study investigated the effect of such surgery on parents' perceptions, both of the current status of their children's functioning and of changes in this functioning. Perceptions of parents of children who had undergone this surgery in Israel in the years 1982 and 1983 were compared with perceptions of parents of children who had not undergone the operation. This comparison produced little evidence for the positive impact of the surgery on parents' perceptions of their children's physical, personal, and social functioning.

Activities of Daily Living↗
PubMed1992

Expression of tenascin in the developing and adult cerebellar cortex.

Since tenascin may influence neuronal cell development, we studied its expression pattern using immunocytochemistry, in situ hybridization, Northern blot analysis, and immunochemistry in the developing and adult mouse cerebellar cortex. Tenascin immunoreactivity was detectable in all layers of the developing cerebellar cortex. In the external granular layer, only the radially oriented processes of Golgi epithelial cells were immunoreactive, whereas the densely packed cell bodies were immunonegative. Tenascin was hardly detectable at contact sites between migrating granule cells and processes of Golgi epithelial cells. Axons of granule cells in the molecular layer were immunoreactive, whereas their cell bodies in the internal granular layer lacked detectable levels of tenascin. By in situ hybridization, only Golgi epithelial cells and astrocytes of the internal granular layer and prospective white matter, but not nerve cells, could be shown to synthesize detectable levels of tenascin mRNA in the developing mouse cerebellar cortex. Thus, tenascin in the cerebellar cortex seems to be a glia-derived molecule that becomes adsorbed to neuronal surfaces in a topographically restricted pattern in situ. Levels of tenascin protein and mRNA decreased significantly with increasing age. In the adult, tenascin immunoreactivity was weak and mainly restricted to the molecular layer and tenascin mRNA was confined to Golgi epithelial cells, indicative for a functional heterogeneity in differentiated cerebellar astrocytes. Quantitative immunoblot analysis revealed that the 225 and 240 kDa components of tenascin were developmentally downregulated at a faster rate than the 190 and 200 kDa components, corresponding to the faster downregulation of the 8 kilobase (kb) mRNA species compared to the 6 kb mRNA species as revealed by Northern blot analysis. These observations indicate a differentially regulated expression of the tenascin components. We hypothesize that glia-derived tenascin modifies the functional properties of nerve cell surfaces and that tenascin is involved in such different morphogenetic events as neurite growth and oligodendrocyte distribution.

Animals↗