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5
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EN
ObjectivesEpidemiological observations indicate that female flight attendants are exposed to some reproductive and endocrine system disturbances. The aim of the study was to determine the incidence of hyperprolactinemia among female flight attendants, and to identify factors affecting the secretion of prolactin in female flight attendants working within 1 time zone as well as on long-distance flights.Material and MethodsThe cross-sectional study covered 103 women aged 23–46 years. The study group (I) was divided into 2 subgroups: subgroup Ia comprising female flight attendants flying within 1 flight zone, and subgroup Ib composed of female flight attendants working on long-distance flights. The control group (II) included women of reproductive age who sought medical assistance due to marital infertility in whom the male factor was found to be responsible for problems with conception in the course of the diagnostic process. The assessment included: age, the body mass index, menstrual cycle regularity, the length of service, the frequency of flying, the prolactin, estradiol and progesterone concentrations, and the result of endometrial biopsy. Descriptive and inferential statistics methods were used to compile the data.ResultsThe incidence of hyperprolactinemia in the female flight attendants (46%) was significantly higher than in the control group (9%), p < 0.001. Differences between subgroups Ia and Ib regarding individual concentrations were not statistically significant (p = 0.425). Hyperprolactinemia among the female flight attendants working ≥15 years is present slightly more often than in those working <15 years: 46% vs. 45% (p > 0.05). No significant difference was revealed in the secretion of prolactin between the study participants spending <60 h/month flying and those spending ≥60 h/month flying (p > 0.05).ConclusionsHyperprolactinemia is more common in female flight attendants than in the general population. High values of prolactin concentration in flight attendants are rarely manifested in clinical symptoms. The frequency of flying and the length of service do not affect the development of hyperprolactinemia or the mean prolactin concentration.
EN
Objectives Welding processes that generate fumes containing toxic metals, such as hexavalent chromium (Cr(VI)), manganese, and nickel (Ni), have been implicated in lung injury, inflammation, and lung tumor promotion in animal models. Bronchiolar epithelium Clara cells/club cells, coordinate these inflammatory responses. Clara cells secretory protein (CC16) with ant-inflammatory role. Material and Methods The pulmonary toxicity of welding dust (WD) was assessed for Wistar rats exposed to 60 mg/m³ of respirable-size welding dust (mean diameter 1.17 μm for 1 and 2 weeks (6 h/day, 5 days/week)) or the aerosols of soluble form (SWD) in the nose-only exposure chambers. Additionally the effect of antiinflammatory betaine supplementation was assessed. Clara cells secretory protein, differential cell counts, total protein concentrations and cellular enzyme (lactate dehydrogenase – LDH) activities were determined in bronchoalveolar lavage fluid, and corticosterone and thiobarbituric acid reactive substances (TBARS) and prolactin concentrations were assessed in serum. Histopathology examination of lung, brain, liver, kidney, spleen was done. Additionally slices of brain and lung were exanimated in laser ablation inductively coupled plasma mass spectrometry. Results Both WD and SWD exposure evoked large bronchiolar infiltration shoved in histopathology examination. In this study, TBARS inversely correlated with a significant decrease of CC16 concentration that occurred after instillation of both WD and SWD indicating decreased anti- inflammatory potential in the lung. In WD exposed rats prolactin correlated with nuclear factor-kappa B (NF-κB), LDH, TBARS and serum levels Cr, Ni and inversely with c-Jun. In SWD exposed rats prolactin correlated with CC16 indicated effect of prolactin on the population of epithelial cells. Conclusions In the current study, deleterious effects of repeated inhalation stainless steel welding dust form on club (Clara) cell secretory protein (CC16) were demonstrated. Clara cells secretory protein relation with prolactin in exposed rats to welding dust were shown and explored whether the NF-κB and c-Jun/activator protein 1 related pathway was involved. Int J Occup Med Environ Health 2018;31(5):613–632
EN
Prolactin (PRL) acts in the body as a hormone secreted into the blood and as a cytokine. In this review after a brief presentation of the structure of PRL and its receptor, we have focused on local hormone secretion by endometrial and ovarian cancer cells. We have discussed the available information about the autocrine/paracrine hormone signaling pathway in the endometrium and ovary. More attention was focused on the role of PRL in endometrial and ovarian cancers. What is more, the clinical aspects related to the diagnosis and new therapeutic options in these tumors are described. At the end, we have included the suggestion that a number of interesting and important problems of both cancers concerning the pathology and treatment have not yet been discovered, which is a challenge for future research.
PL
Prolaktyna (PRL) działa w organizmie człowieka jako hormon wydzielany do krwi i jako cytokina. W pracy, po krótkim przedstawieniu struktury PRL i jej receptora, skoncentrowano się na lokalnym wydzielaniu hormonu przez endometrium i komórki jajnika. Omówiono dostępne informacje na temat auto- i parakrynnego działania hormonu w endometrium i jajniku. Zwrócono uwagę na rolę PRL w rakach endometrium i jajnika oraz na kliniczne aspekty dotyczące diagnostyki i nowych możliwości terapeutycznych w tych nowotworach, wynikające z badań nad osią PRL–PRLR. W zakończeniu zasugerowano, iż wiele interesujących problemów, ważnych z punktu widzenia patologii i kliniki obu nowotworów, nie zostało jeszcze odkrytych, stanowiąc wyzwanie dla przyszłych badań.
8
Content available Prolaktyna i inne regulatory wchłaniania wapnia
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EN
Absorption of calcium is regulated by many endogenous and exogenous factors. Prolactin is important regulator. Numerous studies indicate that prolactin can stimulate calcium transport in the small intestine in vitro and in vivo. This is especially important during the growing demand for calcium in pregnancy and in lactation. There is report the role of prolactin in maintaining calcium homeostasis.
PL
Wchłanianie wapnia regulują liczne czynniki endogenne i egzogenne, m.in. prolaktyna. Jak wynika z wielu badań, może ona stymulować transport wapnia w jelicie cienkim w warunkach in vitro oraz in vivo. Jest to szczególnie ważne w okresie wzrostu zapotrzebowania na wapń w okresie ciąży i laktacji. W licznych doniesieniach wskazano na rolę prolaktyny w zachowaniu homeostazy wapniowej.
EN
The aim of the present study was to evaluate the possible direct effects of GnRH, oxytocin (OT) and vasoactive intestinal peptide (VIP) on the release of LH and PRL by dispersed porcine anterior pituitary cells. Pituitary glands were obtained from mature gilts, which were ovariektomized (OVX) one month before slaughter. Gilts randomly assigned to one of the four groups were treated: in Group 1 (n=8) with 1 ml/100 kg b.w. corn oil (placebo); in Group 2 (n=8) and Group 3 (n=8) with estradiol benzoate (EB) at the dose 2.5 mg/100 kg b.w., respectively, 30-36 h and 60-66 h before slaughter; and in Group 4 (n=9) with progesterone (P4) at the dose 120 mg/100 kg b.w. for five consecutive days before slaughter. In gilts of Group 2 and Group 3 treatments with EB have induced the negative and positive feedback in LH secretion, respectively. Isolated anterior pituitary cells (106/well) were cultured in McCoy's 5a medium with horse serum and fetal calf serum for 3 days at 37°C under the atmosphere of 95% air and 5% CO2. Subsequently, the culture plates were rinsed with fresh McCoy's 5A medium and the cells were incubated for 3.5 h at 37°C in the same medium containing one of the following agents: GnRH (100 ng/ml), OT (10-1000 nM) or VIP (1-100 nM). The addition of GnRH to cultured pituitary cells resulted in marked increases in LH release (p<0.001) in all experimental groups. In the presence of OT and VIP we noted significant increases (p<0.001) in LH secretion by pituitary cells derived from gilts representing the positive feedback phase (Group 3). In contrast, OT and VIP were without any effect on LH release in Group 1 (placebo) and Group 2 (the negative feedback). Pituitary cells obtained from OVX gilts primed with P4 produced significantly higher amounts (p<0.001) of LH only after an addition of 100 nM OT. Neuropeptide GnRH did not affect PRL secretion by pituitary cells obtained from gilts of all experimental groups. Oxytocin also failed to alter PRL secretion in Group 1 and Group 2. However, pituitary cells from animals primed with EB 60-66 h before slaughter and P4 produced markedly increased amounts of PRL in the presence of OT. Neuropeptide VIP stimulated PRL release from pituitary cells of OVX gilts primed with EB (Groups 2 and 3) or P4. In contrast, in OVX gilts primed with placebo, VIP was without any effect on PRL secretion. In conclusion, the results of our in vitro studies confirmed the stimulatory effect of GnRH on LH secretion by porcine pituitary cells and also suggest a participation of OT and VIP in modulation of LH and PRL secretion at the pituitary level in a way dependent on hormonal status of animals.
20
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EN
Prolactin - a hormone secreted in a circadian rhythm acts as a regulator of growth and development of the mammary glands. It has been observed that working at night increases breast cancer risk in women. Night shift work, probably carcinogenic to humans (Group 2A IARC), can disrupt a circadian rhythm, and thus potentially alter the rhythm of prolactin secretion. The aim of our work was to review epidemiological evidence on the association between prolactin and the risk of breast cancer and the influence of work at night on prolactin secretion. Search was done in the Medline database by keywords (shift work, work at night, risk of breast cancer and prolactin). The increased proliferation of breast cells activated by prolactin can promote the development of cancer. The results of the largest epidemiological prospective studies suggest the association between prolactin levels and the risk of breast cancer in women. So far, only seven studies have investigated the association between work at night and prolactin secretion. In three studies lower concentrations of prolactin have been observed in night shift workers. No relationship between the night shift work duration and prolactin level in women have been reported. Night shift work can modify the profile of prolactin secretion in night workers, probably decreasing the secretion of this hormone at night. It is therefore unlikely that prolactin plays an important role in the development of breast cancer in women working at night. This conclusion is based on the results of a few epidemiological studies. Med Pr 2013;64(2):245–257
PL
Prolaktyna jest hormonem wydzielanym w rytmie okołodobowym, pełniącym funkcję regulatora wzrostu i rozwoju gruczołów piersiowych. W przypadku pracy w nocy - uznanej za czynnik prawdopodobnie rakotwórczy u ludzi - obserwuje się zwiększone ryzyko zachorowania na raka piersi u kobiet pracujących w nocy. Praca nocna może powodować zaburzenia rytmu okołodobowego, więc potencjalnie może modyfikować rytm wydzielania prolaktyny. Celem niniejszej pracy był przegląd badań epidemiologicznych dotyczących związku między prolaktyną a ryzykiem zachorowania na raka piersi oraz wpływu pracy nocnej na wydzielanie prolaktyny u pracowników. Publikacje dotyczące tej tematyki wyszukiwano w bazie Medline z użyciem słów kluczowych (praca zmianowa, praca w nocy, ryzyko raka piersi a poziom prolaktyny). Wzmożona proliferacja komórek gruczołu piersiowego aktywowana prolaktyną może być przyczyną rozwoju nowotworu. Wyniki dużych badań prospektywnych wskazują na istniejącą zależność między wysokim stężeniem prolaktyny a zwiększonym ryzykiem zachorowania na raka piersi u kobiet. Jak dotąd przeprowadzono tylko 7 badań, w których analizowano wydzielanie prolaktyny u osób pracujących w nocy. W 3 badaniach, w których oznaczano stężenia prolaktyny kilkakrotnie w nocy, obserwowano niższe stężenia hormonu u osób pracujących w czasie zmiany nocnej. Nie zaobserwowano zależności między długością stażu pracy na zmiany nocne kobiet a stężeniem prolaktyny. Praca w nocy może modyfikować profil nocnej sekrecji prolaktyny u pracowników, z najprawdopodobniej zmniejszeniem wydzielania tego hormonu w nocy. Jest więc mało prawdopodobne, aby prolaktyna odgrywała istotną rolę w rozwoju raka piersi u kobiet pracujących na zmiany nocne. Wniosek ten powstał jednak w oparciu o wyniki nielicznych badań epidemiologicznych. Med. Pr. 2013;64(2):245–257
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