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Hormonal Influences (hormonal + influence)
Selected AbstractsHormonal influences on lipoprotein(a) metabolismDIABETES OBESITY & METABOLISM, Issue 3 2002R. W. C. Pang First page of article [source] Resolution of Menstrually Related Migraine Following Aggressive Treatment for Breast CancerHEADACHE, Issue 3 2010Todd A. Smitherman PhD (Headache 2010;50:485-496) Hormonal influences associated with the female menstrual cycle play strong roles in both migraine and particular types of breast cancer, but there is limited literature on the effects of breast cancer treatment regimens in women with migraine. The present case describes resolution of menstrually related migraine following aggressive treatment for infiltrating ductal carcinoma (neoadjuvant chemotherapy, single radical mastectomy, and locoregional radiation therapy) that was maintained with supplemental treatment using tamoxifen, an anti-estrogenic agent. This novel case is presented to stimulate further research into the hormonal mechanisms underlying migraine. [source] Influence of hormones and hormone metabolites on the growth of schwann cells derived from embryonic stem cells and on tumor cell lines expressing variable levels of neurofibromin,DEVELOPMENTAL DYNAMICS, Issue 2 2008Therese M. Roth Abstract Loss of neurofibromin, the protein product of the tumor suppressor gene neurofibromatosis type 1 (NF1), is associated with neurofibromas, composed largely of Schwann cells. The number and size of neurofibromas in NF1 patients have been shown to increase during pregnancy. A mouse embryonic stem cell (mESC) model was used, in which mESCs with varying levels of neurofibromin were differentiated into Schwann-like cells. NF1 cell lines derived from a malignant and a benign human tumor were used to study proliferation in response to hormones. Estrogen and androgen receptors were not expressed or expressed at very low levels in the NF1+/+ cells, at low levels in NF1+/,cells, and robust levels in NF1,/,cells. A 17,-estradiol (E2) metabolite, 2-methoxy estradiol (2ME2) is cytotoxic to the NF1,/, malignant tumor cell line, and inhibits proliferation in the other cell lines. 2ME2 or its derivatives could provide new treatment avenues for NF1 hormone-sensitive tumors at times of greatet hormonal influence. Developmental Dynamics 237:513,524, 2008. © 2008 Wiley-Liss, Inc. [source] Recurrent erythema multiforme triggered by progesterone sensitivityJOURNAL OF CUTANEOUS PATHOLOGY, Issue 11 2010Teresa J. Nasabzadeh Determining the underlying etiology of recurrent erythema multiforme (EM) can be a difficult endeavor. Although infection with herpes simplex virus (HSV) has been implicated in some cases, the precise trigger of a given patient's recurrent EM often remains elusive. We discuss the case of a woman with a recurrent blistering eruption that was clinically and histopathologically consistent with EM. An investigation into the etiology of the patient's EM suggested that HSV was not the causative factor but instead pointed toward a hormonal influence that we interpret as autoimmune progesterone dermatitis (APD). This case is presented to highlight the importance of considering hormonal triggers in women with recurrent EM that consistently flares during the luteal phase of the menstrual cycle, the point at which serum progesterone levels peak. A brief review of the literature regarding the diagnosis, histopathology, etiology and treatment of APD is further provided. Nasabzadeh TJ, Stefanato CM, Doole JE, Radfar A, Bhawan J, Venna S. Recurrent erythema multiforme triggered by progesterone sensitivity. [source] Stress, the hippocampus, and epilepsyEPILEPSIA, Issue 4 2009Marian Joëls Summary Stress is among the most frequently self-reported precipitants of seizures in patients with epilepsy. This review considers how important stress mediators like corticotropin-releasing hormone, corticosteroids, and neurosteroids could contribute to this phenomenon. Cellular effects of stress mediators in the rodent hippocampus are highlighted. Overall, corticosterone,with other stress hormones,rapidly enhances CA1/CA3 hippocampal activity shortly after stress. At the same time, corticosterone starts gene-mediated events, which enhance calcium influx several hours later. This later effect serves to normalize activity but also imposes a risk for neuronal injury if and when neurons are concurrently strongly depolarized, for example, during epileptic activity. In the dentate gyrus, stress-induced elevations in corticosteroid level are less effective in changing membrane properties such as calcium influx; here, enhanced inhibitory tone mediated through neurosteroid effects on ,-aminobutyric acid (GABA) receptors might dominate. Under conditions of repetitive stress (e.g., caused from experiencing repetitive and unpredictable seizures) and/or early life stress, hormonal influences on the inhibitory tone, however, are diminished; instead, enhanced calcium influx and increased excitation become more important. In agreement, perinatal stress and elevated steroid levels accelerate epileptogenesis and lower seizure threshold in various animal models for epilepsy. It will be interesting to examine how curtailing the effects of stress in adults, for example, by brief treatment with antiglucocorticoids, may be beneficial to the treatment of epilepsy. [source] 5,-Reductase type 2 gene variant associations with prostate cancer risk, circulating hormone levels and androgenetic alopeciaINTERNATIONAL JOURNAL OF CANCER, Issue 4 2007Vanessa M. Hayes Abstract Controversy exists over the significance of associations between the SRD5A2 (5,-reductase type 2) polymorphisms, A49T and V89L, and risk of prostate cancer. These potentially functional polymorphisms may alter life-long exposure to androgens with subsequent effects on male health and aging. The aim of this study was to examine the association of these variants with prostate cancer risk, plasma hormone levels and androgenetic alopecia. Subjects include 827 cases and 736 controls from an Australian population-based case,control study of prostate cancer. Information on prostate cancer risk factors and patterns of balding were collected. Plasma levels of testosterone, 3,-diol glucuronide (3,-diolG), dehydroepiandrosterone sulfate, androstenedione, sex hormone-binding globulin and estradiol were measured for controls. No associations with the V89L polymorphism were found. Carriers of the rarer A49T A allele were at a 60% higher risk of prostate cancer (OR = 1.60; 95% CI 1.09,2.36; p = 0.02) and 50% lower risk of vertex and frontal balding (p = 0.03) compared with men homozygous for the more common G allele. Although we found little evidence of association between this variant and plasma levels of 5 measured androgens, circulating 3,-diolG levels were 34% lower in A49T A allele carriers (p < 0.0001). Our study provides evidence that the SRD5A2 A49T A variant is associated with an increased risk of prostate cancer, lower levels of circulating 3,-diolG and decreased risk of baldness. These findings raise important questions with respect to previous assumptions concerning hormonal influences on prostate cancer risk in ageing males. © 2006 Wiley-Liss, Inc. [source] Striatal susceptibility to a dopaminergic neurotoxin is independent of sex hormone effects on cell survival and DAT expression but is exacerbated by central aromatase inhibitionJOURNAL OF NEUROCHEMISTRY, Issue 3 2007Simon McArthur Abstract The aim of this study was to investigate further the hormone-dependent processes underlying sex differences in neurotoxic responses within the rat nigrostriatal dopaminergic (NSDA) pathway after partial lesioning with 6-OHDA, a state thought to mimic the early stages of Parkinson's disease where, in humans and animal models alike, males appear to be more susceptible. Contrary to our hypotheses, hormone manipulations (gonadectomy ± oestrogen or androgen treatment) failed to alter survival of tyrosine hydroxylase immunoreactive cells in the substantia nigra pars compacta (SNc) after lesioning; this indicates that, unlike inherent sex differences in toxin-induced striatal dopamine depletion, sex differences in cell loss were not hormonally generated, and that hormone-dependent changes in dopamine depletion can occur independently of cell survival. In addition, hormonally induced changes in striatal expression of the dopamine transporter (DAT), an important factor for 6-OHDA toxicity, did not correlate with hormonal influences on striatal dopamine loss and, in males, central inhibition of aromatase prior to 6-OHDA infusion exacerbated striatal dopamine loss with no effect on SNc tyrosine hydroxylase-immunoreactive survival, suggesting locally generated oestrogen is neuroprotective. These results support the novel view that sex steroid hormones produced peripherally and centrally play a significant, sex-specific role within the sexually dimorphic NSDA pathway to modulate plastic, compensatory responses aimed at restoring striatal dopamine functionality, without affecting cell loss. [source] Center of body mass and the evolution of female body shapeAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 2 2003Bogus, aw Paw, owski Among primates, the genus Homo has a unique sexual dimorphism in general body shape. The stenotypic female "hourglass figure" has often been attributed to sexual selection. Sexual dimorphism both in shape and in position of the center of body mass (CoM) emerges during puberty and is related to hormonal influences. These are only the proximal and not the ultimate causes of this feature. This article explores the hypothesis that the evolutionary (i.e., ultimate) reason for female body shape and male preference for a lower waist-to-hip ratio (WHR) is due to the acquisition of bipedal locomotion and different biomechanical constraints on each sex. The demands of pregnancy and subsequently carrying infants may have more tightly constrained CoM in females than in males. A lower-position of CoM relative to height (RCoM=(CoM/height)*100%) would contribute to better stability during pregnancy and infant carrying. Using body measurements from 119 female students, we show that RCoM correlates negatively with only maximal thigh circumference and positively with only WHR and shoulder width. The relationship between RCoM and traits that best characterize female body shape seems to confirm a hypothesis of biomechanical selection pressure that may have acted on Homo female morphology, thus contributing to sexual dimorphism. Am. J. Hum. Biol. 15:144,150, 2003. © 2003 Wiley-Liss, Inc. [source] Insulin treatment in children and adolescentsACTA PAEDIATRICA, Issue 4 2004RM Williams The management of diabetes in children presents a number of challenges. The ideal is to achieve optimal glycaemic control using an insulin regimen that is acceptable to the child and family, which improves glycaemic control, whilst avoiding hypoglycaemia. The paediatric population differ from their adult counterparts in several ways, such as variability of exercise and eating patterns, and the hormonal influences of puberty, which means that the insulin regimen must be tailored to suit an individual child and their family. Conclusion: This review will focus on the particular difficulties of managing diabetes in children and, in particular, the problem of avoiding hypoglycaemia while maintaining adequate glycaemic control. [source] | |||||||||||||