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1.
Int J Nurs Stud ; 114: 103852, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33360666

RESUMO

BACKGROUND: A range of classification systems are in use for the measurement of nursing workload in Intensive Care Units. However, it is unknown to what extent the measured (objective) nursing workload, usually in terms of the amount of nursing activities, is related to the workload actually experienced (perceived) by nurses. OBJECTIVES: The aim of this study was to assess the association between the objective nursing workload and the perceived nursing workload and to identify other factors associated with the perceived nursing workload. METHODS: We measured the objective nursing workload with the Nursing Activities Score and the perceived nursing workload with the NASA-Task Load Index during 228 shifts in eight different Intensive Care Units. We used linear mixed-effect regression models to analyze the association between the objective and perceived nursing workload. Furthermore, we investigated the association of patient characteristics (severity of illness, comorbidities, age, body mass index, and planned or unplanned admission), education level of the nurse, and contextual factors (numbers of patients per nurse, the type of shift (day, evening, night) and day of admission or discharge) with perceived nursing workload. We adjusted for confounders. RESULTS: We did not find a significant association between the observed workload per nurse and perceived nursing workload (p=0.06). The APACHE-IV Acute Physiology Score of a patient was significantly associated with the perceived nursing workload, also after adjustment for confounders (p=0.02). None of the other patient characteristics was significantly associated with perceived nursing workload. Being a certified nurse or a student nurse was the only nursing or contextual factor significantly associated with the perceived nursing workload, also after adjustment for confounders (p=0.03). CONCLUSION: Workload is perceived differently by nurses compared to the objectively measured workload by the Nursing Activities Score. Both the severity of illness of the patient and being a student nurse are factors that increase the perceived nursing workload. To keep the workload of nurses in balance, planning nursing capacity should be based on the Nursing Activities Score, on the severity of patient illness and the graduation level of the nurse.

3.
Neurocrit Care ; 5(3): 186-92, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17290086

RESUMO

INTRODUCTION: Seizures are common in Intensive Care Unit (ICU) patients, and may increase neuronal injury. PURPOSE: To explore the possible value of synchronization likelihood (SL) for the automatic detection of seizures in adult ICU patients. METHODS: We included EEGs from ICU patients with a variety of diagnoses. The gold standard for further analyses was the consensus judgment of three clinical neurophysiologists who classified 150 scalp EEG epochs as "definitely epileptiform," "definitely non epileptiform," or "uncertain." SL estimates the statistical interdependencies between two time series, such as two EEG channels. We computed the average synchronization by calculating the SL between one channel and every other channel, and taking the mean of these values. RESULTS: The mean SL in the 38 "definitely epileptiform" epochs ranged from 0.095 to 0.386 (mean 0.189; SD 0.066). In the 34 "definitely nonepileptiform" epochs the mean SL ranged from 0.087 to 0.158 (mean 0.115; SD 0.016; p < 0.0005). The area under the ROC curve was 0.812 (95% Confidence Interval 0.725 to 0.898). CONCLUSION: The mean SL may distinguish between seizure and nonseizure epochs, and may prove helpful to monitor epileptic activity in ICU patients.


Assuntos
Sincronização Cortical , Eletroencefalografia/estatística & dados numéricos , Epilepsia/diagnóstico , Unidades de Terapia Intensiva , Estado Epiléptico/diagnóstico , Córtex Cerebral/fisiopatologia , Diagnóstico Diferencial , Epilepsia/etiologia , Epilepsia/fisiopatologia , Potenciais Evocados/fisiologia , Humanos , Funções Verossimilhança , Dinâmica não Linear , Variações Dependentes do Observador , Curva ROC , Processamento de Sinais Assistido por Computador , Estado Epiléptico/etiologia , Estado Epiléptico/fisiopatologia
4.
Ned Tijdschr Geneeskd ; 150(50): 2770-3, 2006 Dec 16.
Artigo em Holandês | MEDLINE | ID: mdl-17225791

RESUMO

A 32-year-old man who had undergone kidney transplantation presented with malaise, severe diarrhoea, nausea and vomiting, productive cough and shortness of breath. A 42-year-old woman with no relevant medical history presented with fever, weight loss and abdominal pain. Both patients had lactic acidosis and hypoglycaemia. Initially, the hyperlactataemia was thought to result from tissue hypoxia (sepsis) but it persisted after correction of the hypovolaemia; therefore, alternative causes were considered. Both patients were found to have T-cell lymphoma with liver infiltration. The male patient died before treatment could be initiated. The lactic acidosis resolved in the female patient following lymphoma treatment, but she died subsequently from the lymphoma. Lymphoreticular malignancies should be considered for cases of lactic acidosis with sufficient oxygen supply, particularly when hypoglycaemia is also present. The lactic acidosis and hypoglycaemia result from increased anaerobic glycolysis in tumour cells. Tumour reduction with chemotherapy can reduce the lactic acidosis.


Assuntos
Acidose Láctica/etiologia , Hipoglicemia/etiologia , Linfoma de Células T/complicações , Acidose Láctica/diagnóstico , Adulto , Evolução Fatal , Feminino , Humanos , Hipoglicemia/diagnóstico , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundário , Linfoma de Células T/diagnóstico , Masculino
5.
Acta Anaesthesiol Scand ; 49(9): 1302-10, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16146467

RESUMO

BACKGROUND: Cardiac surgery can be complicated by pulmonary abnormalities, but it is unclear how various manifestations interrelate. METHODS: A prospective study in the intensive care unit was performed on 26 mechanically ventilated patients without cardiac failure within 3 h after elective cardiac surgery involving cardiopulmonary bypass. Oedema (extravascular lung water, EVLW) was measured by the thermal-dye technique and permeability by a dual radionuclide technique, yielding a pulmonary leak index (PLI). Radiographic, mechanical and gas exchange features were used to calculate the lung injury score (LIS), ranging between 0 and 4. Evidence for left lower lobe atelectasis was obtained from plain radiographs. The plasma colloid osmotic pressure (COP) was measured by an oncometer. RESULTS: The EVLW (normal, <7 ml/kg) was elevated in 36% of patients and the PLI (normal, <14.1 x 10(-3)/min) in 44%, but the variables did not interrelate directly. Patients with a supranormal EVLW had a lower COP than patients with normal EVLW. The duration of mechanical ventilation was prolonged in patients (20%) with EVLW > 10 ml/kg. There was no difference in EVLW and PLI in patients with LIS < 1 and LIS > 1 (31% of patients). In patients with radiographic evidence for atelectasis (46%), the positive end-expiratory pressure and inspiratory O2 fraction to maintain oxygenation were higher than in those without. CONCLUSIONS: After cardiac surgery, mild pulmonary oedema is relatively common, even in the absence of high filling pressures, and is mainly attributable to a low COP, irrespective of increased permeability in about one-half of patients. It may prolong mechanical ventilation at EVLW > 10 ml/kg. However, pulmonary radiographic and ventilatory abnormalities may result, at least in part, from atelectasis rather than increased permeability oedema.


Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Pneumopatias/etiologia , Atelectasia Pulmonar/etiologia , Edema Pulmonar/etiologia , Adulto , Idoso , Ponte Cardiopulmonar , Cuidados Críticos , Água Extravascular Pulmonar/fisiologia , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pneumopatias/patologia , Pneumopatias/fisiopatologia , Masculino , Pessoa de Meia-Idade , Pressão Osmótica , Permeabilidade , Estudos Prospectivos , Atelectasia Pulmonar/patologia , Atelectasia Pulmonar/fisiopatologia , Edema Pulmonar/patologia , Edema Pulmonar/fisiopatologia , Troca Gasosa Pulmonar/fisiologia , Radiografia , Testes de Função Respiratória
6.
Neth J Med ; 61(10): 337-40, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14708914

RESUMO

A 28-year-old female with a twin pregnancy at 29 6/7 weeks who was having premature uterine contractions developed acute respiratory failure due to sudden pulmonary oedema requiring mechanical ventilation. No evidence for venous thromboembolism, pulmonary infection or myocardial infarction was found. Subsequently a mild coagulopathy and foetal distress developed. Ultrasonography revealed oligohydramnios of one of the foetuses. A Caesarean section was performed and postoperatively mother and babies had an uneventful clinical course. By exclusion of other causes, we diagnosed severe maternal acute respiratory distress due to the amniotic fluid embolism syndrome in a twin pregnancy.


Assuntos
Embolia Amniótica/complicações , Edema Pulmonar/etiologia , /etiologia , Adulto , Cesárea , Diagnóstico Diferencial , Embolia Amniótica/diagnóstico por imagem , Embolia Amniótica/terapia , Feminino , Humanos , Trabalho de Parto Prematuro/etiologia , Gravidez , Edema Pulmonar/terapia , Gêmeos , Ultrassonografia
7.
Perfusion ; 18(6): 369-71, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14714774

RESUMO

A 74-year-old male patient's circulation was supported by an intra-aortic balloon for a period of six days following multiple cardiac infarcts. On the sixth day, several 'leak in IAB circuit' alarms appeared. The nursing staff checked the tubing and refilled the balloon, as described in the manual, without notifying the medical staff or perfusionist. A few hours later, the balloon showed a leak, as blood was seen in the catheter tubing. This leak resulted in considerable damage to the device caused by a large amount of blood migrating back to the tubing and flooding the internal drive system, due to a failing 'blood detection' sensor. The balloon catheter was removed percutaneously and intra-aortic counterpulsation was discontinued. The patient died 20 days later of heart failure. This raises doubts over the adequacy of the protective sensors of such devices and, importantly, how to interpret the present user manuals and the instructions for troubleshooting.


Assuntos
Balão Intra-Aórtico , Idoso , Sangue , Falha de Equipamento , Humanos , Masculino
8.
Intensive Care Med ; 27(9): 1550-2, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11685351

RESUMO

Although the APACHE II score is the most widely used scoring system in intensive care units worldwide, its reliability and variability have not been extensively studied. Differences in case-mix may complicate comparison and interpretation of results. We hypothesised that a degree of variability might be inherent to use of the APACHE II scoring system, and decided to assess intra-observer variability in APACHE II scoring as a potential indicator of inherent score variability. APACHE II scores were assessed twice from the charts of 11 patients by 14 physicians, with a time interval of 4 (range 3.5-4.5) months between the two assessments. Intra-observer was found to be approximately 15%. These findings are in agreement with previous observations regarding inter-observer variability in APACHE II scoring, and strongly suggest that there is an inherent score variability of about 15%.


Assuntos
APACHE , Análise de Variância , Fatores de Confusão Epidemiológicos , Cuidados Críticos/normas , Grupos Diagnósticos Relacionados/classificação , Grupos Diagnósticos Relacionados/estatística & dados numéricos , Seguimentos , Guias como Assunto , Humanos , Capacitação em Serviço , Corpo Clínico Hospitalar/educação , Corpo Clínico Hospitalar/normas , Variações Dependentes do Observador , Sensibilidade e Especificidade , Índice de Gravidade de Doença
12.
Curr Opin Anaesthesiol ; 13(2): 99-103, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17016286

RESUMO

Corticosteroids are of key importance in controlling the immune system and in the maintenance of cardiovascular function. Thus, an adequate function of the adrenal cortex is essential for survival in critical illness. There is growing evidence that adrenocortical function can become impaired during critical illness, because of deleterious effects of cytokines, leading to a state of relative adrenal dysfunction. Under these circumstances, administration of corticosteroids is necessary for recovery of the patient. How such a state of adrenal dysfunction should be detected is still not clear, however, making it difficult to decide when to administer corticosteroids and to which patients.

13.
Fertil Steril ; 55(3): 608-11, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2001760

RESUMO

Polycystic ovary disease generally is associated with elevated androgen levels and elevated luteinizing hormone (LH) levels, whereas follicle-stimulating hormone (FSH) levels are (sub)normal. To assess the role of androgens on gonadotropin secretion, we investigated the effect of 6 weeks of testosterone (T) undecanoate, 120 to 160 mg/d orally, on the parameters of the pulsatile secretion of LH in a group of six eugonadal female-to-male transsexuals with normal menstrual cycles. The treatment suppressed menstrual activity in all patients. Serum T and estrone were significantly elevated after treatment with oral T undecanoate. The parameters of the pulsatile secretion of LH were not affected by androgen administration. Levels of FSH, estradiol, and progesterone also did not change significantly.


Assuntos
Hormônio Luteinizante/metabolismo , Testosterona/análogos & derivados , Transexualidade/metabolismo , Estrona/sangue , Feminino , Humanos , Fluxo Pulsátil , Radioimunoensaio , Testosterona/sangue , Testosterona/farmacocinética , Testosterona/farmacologia
14.
J Clin Endocrinol Metab ; 69(1): 151-7, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2471710

RESUMO

Polycystic ovarian disease (PCOD) is associated with elevated serum LH and (sub)normal FSH levels, while serum androgen levels are often elevated. To clarify the role of androgens in this abnormal pattern of gonadotropin secretion, LH secretion was studied in 1) 9 eugonadal female to male transsexual subjects before and during long term (6 months) testosterone (T) administration (250 mg/2 weeks, im), and 2) in a woman with an androgen-secreting ovarian tumor both before and after surgical removal of the tumor. Finally, we studied the effects of high serum androgen levels on ovarian histology in 3) 26 transsexual subjects after long term (9-36 months) T administration (250 mg/2 weeks, im) to assess whether T-induced ovarian abnormalities are similar to those that occur in women with PCOD. Long term T treatment in the nine female to male transsexual subjects resulted in increases in the mean serum T level from 1.7 +/- 0.8 (+/- SD) to 40.8 +/- 31.9 nmol/L (P less than 0.01), the mean serum dihydrotestosterone level from 0.6 +/- 0.2 to 3.3 +/- 1.5 nmol/L (P less than 0.02), and the mean serum free T level from 9.5 +/- 5.2 to 149 +/- 46 pmol/L (P less than 0.02). Mean serum estrone and estradiol levels were similar before and during T treatment. The mean serum LH level decreased from 6.3 +/- 2.0 to 2.9 +/- 1.1 U/L (P less than 0.01), and the mean FSH levels decreased from 6.6 +/- 2.0 to 3.7 +/- 2.2 U/L (P less than 0.02). Pulsatile LH secretion before and during T treatment was studied in five subjects. Neither the mean nadir LH interval nor the LH pulse amplitude changed significantly in these five subjects. The serum T level in the woman with the androgen-secreting ovarian tumor was 9.6 nmol/L, and it declined to normal after removal of the tumor. Her mean serum LH and FSH levels, the mean nadir LH interval, and LH pulse amplitude were in the normal range before and after removal of the tumor. Studies of ovarian histopathology in 26 transsexual subjects after long term androgen treatment revealed multiple cystic follicles in 18 subjects (69.2%), diffuse ovarian stromal hyperplasia in 21 subjects (80.8%), collagenization of the tunica albuginea in 25 subjects (96.2%), and luteinization of stromal cells in 7 subjects (26.9%). Findings consistent with criteria for the pathological diagnosis of polycystic ovaries, that is 3 of the 4 findings listed above, were present in 18 of the 26 subjects (69.2%).(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Hormônio Luteinizante/sangue , Ovário/efeitos dos fármacos , Testosterona/administração & dosagem , Transexualidade/sangue , Androgênios/sangue , Di-Hidrotestosterona/sangue , Estrona/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Hormônio Luteinizante/metabolismo , Neoplasias Ovarianas/sangue , Ovário/patologia , Síndrome do Ovário Policístico/induzido quimicamente , Síndrome do Ovário Policístico/patologia , Coloração e Rotulagem , Esteroides/sangue , Testosterona/sangue , Testosterona/farmacologia
15.
Psychoneuroendocrinology ; 14(1-2): 97-102, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2499904

RESUMO

It has been suggested that there is a difference in the interaction between sex steroids and gonadotropin secretion between transsexual and heterosexual women. In this study we tested whether there is a difference in the pulsatile release characteristics of luteinizing hormone (LH) and in ovarian steroid concentrations between 16 female-to-male (f-to-m) transsexuals and eight eugonadal heterosexual women during the early follicular phase of the menstrual cycle. Blood samples for LH determination were collected every 10 min for 7 hr in the transsexual group, and every 10 min for 6 hr in the heterosexual group. There were no significant differences between the transsexual and heterosexual group in mean serum LH concentration (6.9 +/- 2.4 U/l vs. 7.5 +/- 2.6 U/l), mean LH nadir interval (77 +/- 37 min vs. 70 +/- 16 min), and mean LH pulse amplitude (2.9 +/- 1.1 U/l vs. 3.0 +/- 1.1 U/l). Serum estrone, 17-beta-estradiol, testosterone, progesterone and FSH concentrations also did not differ between the two groups. There also was not a higher prevalence of polycystic ovarian disease in our f-to-m transsexual group than in the general population.


Assuntos
Identidade de Gênero/fisiologia , Hormônios Esteroides Gonadais/sangue , Identificação Psicológica/fisiologia , Hormônio Luteinizante/sangue , Transexualidade/sangue , Adulto , Estradiol/sangue , Estrona/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Masculino , Ovário/fisiopatologia , Síndrome do Ovário Policístico/sangue , Progesterona/sangue , Testosterona/sangue , Transexualidade/cirurgia
16.
J Clin Endocrinol Metab ; 68(1): 200-7, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2491861

RESUMO

We investigated the effects of long term testosterone (T) administration on pulsatile gonadotropin secretion in agonadal women and the effects of estradiol (E2) on gonadotropin secretion in eugonadal women in the follicular phase of the menstrual cycle. We studied 4 groups: A) 28 eugonadal women in the early follicular phase of the menstrual cycle, B) 11 hypogonadal women, C) 13 agonadal female to male (f-t-m) transsexuals treated for at least 3 months with 120-160 mg T undecanoate (TU)/day, orally, and D) 5 agonadal f-to-m transsexuals treated for at least 6 months with 250 mg of a mixture of testosterone esters, im (im T-esters), every 2 weeks. The eugonadal women in the early follicular phase had a mean serum E2 level of 193 +/- 94 (+/- SD) pmol/L, significantly higher (P less than 0.01) than that in the hypogonadal women (60 +/- 24 pmol/L), whereas there was no difference in the mean serum T levels (1.8 +/- 0.7 vs. 2.3 +/- 1.5 nmol/L). the higher serum E2 level in the eugonadal women was associated with a significantly lower mean serum LH level (6.9 +/- 2.6 vs. 44.6 +/- 17.6 U/L; P less than 0.01) and LH pulse amplitude (2.8 +/- 1.0 vs. 12.6 +/- 4.8 U/L; P less than 0.01), whereas the mean nadir LH interval did not differ between the two groups (75 +/- 29 vs. 81 +/- 49 min). The mean serum T level in the agonadal f-to-m transsexuals treated with oral TU was significantly higher (P less than 0.01) than that in the hypogonadal women (9.7 +/- 4.7 vs. 2.3 +/- 1.5 nmol/L). In spite of this elevated T level there was no difference in the mean serum LH level (38.4 +/- 14.7 vs. 44.6 +/- 17.6 U/L), LH pulse amplitude (14.3 +/- 5.7 vs. 12.6 +/- 4.8 U/L), or nadir LH interval (72 +/- 27 vs. 81 +/- 49 min) in these groups. Also, the mean serum E2 (64 +/- 16 vs. 60 +/- 24 pmol/L and FSH levels (62 +/- 17 vs. 64 +/- 28 U/L) did not differ between these groups. Treatment of the agonadal f-to-m transsexuals with im T-esters resulted in mean serum T and E2 levels of 34.4 +/- 27.0 nmol/L and 121 +/- 54 pmol/L, respectively, both significantly higher (P less than 0.01) than those in groups B and C.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Gonadotropinas/sangue , Hipogonadismo/fisiopatologia , Testosterona/farmacologia , Transexualidade/fisiopatologia , Adulto , Estradiol/sangue , Estrogênios/sangue , Estrogênios/fisiologia , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio Foliculoestimulante/metabolismo , Fase Folicular , Gonadotropinas/metabolismo , Humanos , Hipogonadismo/sangue , Hormônio Luteinizante/sangue , Hormônio Luteinizante/metabolismo , Masculino , Pessoa de Meia-Idade , Transexualidade/sangue
17.
Clin Endocrinol (Oxf) ; 29(2): 179-88, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2854762

RESUMO

Both gonadal steroids and endogenous opioid peptides (EOPs) exert an inhibitory effect on gonadotrophin secretion. It is thought that the negative feedback action of the gonadal steroids, testosterone (T) and oestradiol (E2), on the gonadotrophin secretion is mediated by EOPs. To assess the effects of EOPs and oestrogen and their interrelationship on pulsatile LH secretion we studied two groups of eugonadal men. The subjects of the first group were tested on three different occasions, firstly under basal conditions, secondly during infusion of the opiate receptor blocker naloxone (NAL) (bolus 5 mg + 2.1 mg/h for 7 h), and finally during NAL infusion after 6 weeks administration of the oestrogen receptor blocker tamoxifen (10 mg twice daily). The subjects of the second group were studied before and after 6 weeks administration of tamoxifen. NAL infusion produced a significant increase in mean serum LH levels (4.8 +/- SD 1.5 to 6.2 +/- 1.8 U/l) and LH pulse frequency (3.7 +/- 1.6 to 5.3 +/- 1.2 pulses/7 h). No change was seen in mean LH pulse amplitudes (3.5 +/- 1.5 vs 3.4 +/- 1.0 U/l). After tamoxifen administration alone there was a significant increase in mean LH level (from 5.7 +/- 1.3 to 10.1 +/- 2.4 U/l), LH pulse amplitude (from 3.8 +/- 0.9 to 4.6 +/- 0.9 U/l) and LH pulse frequency (from 4.2 +/- 1.5 to 5.8 +/- 1.7 pulses/7 h). A significant rise in mean serum LH levels was observed during NAL infusion after previous tamoxifen administration in comparison to the infusion of NAL alone (from 6.2 +/- 1.8 to 10.5 +/- 6.2 U/l). LH pulse frequency (5.3 +/- 1.2 vs 6.3 +/- 1.3 pulses/7h) and amplitude (3.4 +/- 1.0 vs 3.6 +/- 1.5 U/l) however, did not change. Mean serum LH level and LH pulse frequency after opiate receptor and oestrogen receptor blockade together did not differ from the results obtained after oestrogen receptor blockade alone. NAL however was expected not only to block opioid-mediated oestrogen action but also androgen action and therefore to have additional effect on LH secretion, whereas tamoxifen was supposed to block only oestrogen action. From these data we conclude that EOPs exert a negative feedback effect on LH secretion by slowing the GnRH pulse generator. Because there was no additional effect of opiate receptor blockade after oestrogen receptor blockade on pulsatile LH secretion we infer that androgens may be impeded in their negative feedback action in the presence of the antioestrogen tamoxifen.


Assuntos
Hormônio Luteinizante/metabolismo , Naloxona/farmacologia , Receptores Opioides/efeitos dos fármacos , Tamoxifeno/farmacologia , Adulto , Retroalimentação , Humanos , Hormônio Luteinizante/sangue , Masculino , Fatores de Tempo
18.
J Clin Endocrinol Metab ; 66(2): 355-60, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3339109

RESUMO

We studied the role of estrogens on LH pulse modulation in men in two ways. Firstly, we compared LH pulse frequency and amplitude in 13 normal men before and after 6 weeks administration of the antiestrogen tamoxifen (10 mg twice daily). Secondly, we compared LH pulse frequency and amplitude between a group of 10 agonadal men not receiving sex steroid treatment and a group of 9 agonadal men (male to female transsexuals) continuously treated with 50 micrograms ethinyl estradiol/day. Tamoxifen administration to normal men resulted in a significant rise in the mean serum LH level from 5.7 +/- 1.3 (+/- SD) to 10.1 +/- 2.4 U/L, which was associated with significant increases in LH pulse frequency (from 4.2 +/- 1.5 to 5.8 +/- 1.7/7 h) and LH pulse amplitude (from 3.8 +/- 0.9 to 4.6 +/- 0.7 U/L). In the group of agonadal men the mean LH pulse frequency was 6.8 +/- 1.5/7 h, while it was 5.9 +/- 1.7/7 h in the estrogen-treated agonadal group (P = NS). The mean serum LH level and LH pulse amplitude were, however, significantly lower in the estrogen-treated agonadal men than in the agonadal men (14.7 +/- 7.0 vs. 34.3 +/- 8.6 and 4.1 +/- 1.8 vs. 7.4 +/- 1.8 U/L, respectively). We conclude that estrogens reduce basal LH levels and LH pulse amplitude. With regard to the modulation of LH pulse frequency our data provide contradictory results. While an antiestrogen increased LH pulse frequency in normal men, estrogen alone produced no change in LH pulse frequency in agonadal men. The study design in the agonadal men ignores the possible interaction of the two major testicular hormones (estradiol and testosterone) on gonadotropin secretion. Therefore, a possible explanation for this discrepancy in the effects of antiestrogen and estrogen could be an interaction between estrogens and androgens on gonadotropin secretion at the level of the LHRH pulse generator.


Assuntos
Estrogênios/fisiologia , Hormônio Luteinizante/sangue , Tamoxifeno/farmacologia , Adulto , Estradiol/sangue , Eunuquismo/sangue , Humanos , Masculino , Periodicidade , Valores de Referência , Testosterona/sangue
19.
Psychoneuroendocrinology ; 13(3): 279-83, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3406325

RESUMO

This study tested whether there is a difference in the pulsatile LH secretion between male-to-female transsexuals and eugonadal heterosexual men. The mean serum LH concentrations, the LH pulse frequency, and the LH pulse amplitude were compared between a group of eight male-to-female transsexuals and a group of 22 heterosexual men. Blood samples for LH determinations were collected every 10 min for seven hours. 17-beta-estradiol and testosterone were measured at the beginning of each test. There were no significant differences between the heterosexual and transsexual group in LH pulse frequency (3.9 +/- 1.3 vs. 3.9 +/- 1.7), LH pulse amplitude (3.7 +/- 1.3 U/l vs. 3.0 +/- 0.5 U/l), mean serum LH concentration (5.2 +/- 1.4 U/l vs. 5.4 +/- 1.1 U/l), 17-beta-estradiol (0.07 +/- 0.01 nmol/l vs. 0.08 +/- 0.02 nmol/l), or testosterone (22.9 +/- 3.7 nmol/l vs. 21.8 +/- 8.0 nmol/l). We conclude that the pulsatile release characteristics of LH do not allow a distinction between eugonadal heterosexual men and eugonadal male-to-female transsexuals.


Assuntos
Hormônio Luteinizante/sangue , Transexualidade/sangue , Adulto , Estradiol/sangue , Humanos , Masculino , Testosterona/sangue
20.
J Clin Endocrinol Metab ; 64(4): 763-70, 1987 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3102546

RESUMO

This study evaluated the effects of estrogens and androgens on LH pulse frequency and amplitude in male subjects. To assess the role of estrogens we compared the serum LH pulse frequency and amplitude between 3 groups: 8 agonadal subjects receiving no steroid treatment; 6 agonadal subjects continuously treated with 50 micrograms ethinylestradiol/day; and 17 eugonadal men. Mean serum LH levels and LH pulse amplitude were significantly lower in the agonadal subjects receiving estrogens (14.8 +/- 5.4 (SD) U/L and 4.1 +/- 1.5 U/L, respectively) than in the group of agonadal subjects not receiving sex steroid treatment (35.7 +/- 8.4 U/L and 7.3 +/- 2.0 U/L, respectively). The mean LH pulse frequency was 7.1 +/- 1.5/7 h in the group not receiving sex steroid treatment and 6.0 +/- 1.4/7 h in the group receiving estrogens (P NS). The LH pulse frequency in the eugonadal men (3.8 +/- 1.3/7 h) was significantly lower than the frequency in both groups of agonadal subjects. The LH pulse amplitude was of the same magnitude in the estrogen-treated agonadal subjects and in eugonadal men (4.1 +/- 1.5 U/L and 3.5 +/- 1.2 U/L, respectively). The role of androgens was studied in 15 eugonadal male subjects (who presented for female role reassignment) by determining the effects of a novel nonsteroidal androgen receptor blocker, Anandron, on basal and LH-releasing hormone (LHRH)-stimulated serum LH/FSH levels; LH pulse frequency and amplitude; sex steroid and sex hormone-binding globulin levels; and serum PRL levels during an 8-week period. Basal and LHRH-stimulated LH levels and testosterone rose progressively during the first 6 weeks and reached a plateau thereafter, while estradiol levels continued to increase somewhat. The LH pulse amplitude and frequency had increased after 6 weeks (3.1 +/- 0.6 vs. 4.5 +/- 1.2 U/L and 4.4 +/- 2.4 vs. 6.6 +/- 1.1 pulses/7 h, respectively). Basal FSH levels were not affected while LHRH-stimulated FSH levels progressively decreased from 2 to 6 weeks, after which they did not change. Along with the rise of estradiol levels an increase of sex hormone-binding globulin and PRL levels occurred.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Antagonistas de Androgênios/farmacologia , Estrogênios/farmacologia , Imidazóis/farmacologia , Imidazolidinas , Hormônio Luteinizante/metabolismo , Transexualidade/sangue , Adulto , Hormônio Foliculoestimulante/sangue , Hormônios Esteroides Gonadais/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Orquiectomia , Globulina de Ligação a Hormônio Sexual/metabolismo
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