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1.
Oecologia ; 170(2): 341-53, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22526940

RESUMO

Climate change is driving species range shifts worldwide. However, physiological responses related to distributional changes are not fully understood. Oceanographers have reported an increase in ocean temperature in the northwest Iberian Peninsula that is potentially related to the decline in some cold-temperate intertidal macroalgae in the Cantabrian Sea, namely Fucus serratus. Low tide stress could also play a role in this decline. We performed one mensurative (in situ) and two manipulative (in culture) experiments designed to evaluate the interactive effects of some physical factors. The first experiment analysed field response to low tide stress in marginal (mid-Cantabrian Sea and northern Portugal) versus central (Galicia) populations of F. serratus. Then a second experiment was performed that utilized either harsh or mild summer conditions of atmospheric temperature, irradiance, humidity, and wind velocity to compare the responses of individuals from one marginal and one central population to low tide stress. Finally, the combined effect of sea temperature and the other factors was evaluated to detect interactive effects. Changes in frond growth, maximal photosynthetic quantum yield (F(v)/F(m)), temperature, and desiccation were found. Three additive factors (solar irradiation, ocean and air temperatures) were found to drive F. serratus distribution, except under mildly humid conditions that ameliorated atmospheric thermal stress (two additive factors). Mid-Cantabrian Sea temperatures have recently increased, reaching the inhibitory levels suggested in this study of F. serratus. We also expect an additive secondary contribution of low tide stress to this species decline. On the northern Portugal coast, ocean warming plus low tide stress has not reached this species' inhibition threshold. No significant differential responses attributed to the population of origin were found. Mechanistic approaches that are designed to analyse the interactive effects of physical stressors may improve the levels of confidence in predicted range shifts of species.


Assuntos
Fucus/crescimento & desenvolvimento , Aquecimento Global , Estresse Fisiológico , Biologia Marinha , Dinâmica Populacional , Portugal , Estações do Ano , Temperatura
2.
Reprod Biomed Online ; 22 Suppl 1: S43-51, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21575849

RESUMO

This single-centre, randomized, parallel group, comparative study aimed to identify potential benefits of mid-follicular recombinant human LH (r-HLH) supplementation in women aged 35-39 years undergoing ovarian stimulation for intracytoplasmic sperm injection (ICSI). The main endpoint was the number of metaphase II oocytes retrieved. After pituitary suppression with a gonadotrophin-releasing hormone agonist, ovarian stimulation was initiated with recombinant human FSH (r-HFSH; 300-450 IU/day). On stimulation day 6, patients were randomized to receive r-HFSH alone or r-HFSH + r-HLH (r-HLH 150 IU/day) for the remainder of the stimulation period. Final follicular maturation was triggered with 250 µg of recombinant human chorionic gonadotrophin. After assessing oocyte nuclear maturity, oocyte were fertilized by ICSI and afterwards embryo quality was analyzed. Of the 131 women enrolled, 68 were allocated to r-HFSH alone and 63 to r-HFSH + r-HLH. No significant differences were observed in markers of either oocyte or embryo quality or quantity. However, higher rates of implantation and live birth per started cycle were observed with r-HLH supplementation than with r-HFSH alone. Although additional large studies are required to further investigate these findings, r-HLH supplementation for women aged 35-39 years undergoing ICSI is recommended as it may have a beneficial action on implantation.

3.
Reprod Biomed Online ; 19(6): 879-87, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20031032

RESUMO

This single-centre, randomized, parallel group, comparative study aimed to identify potential benefits of mid-follicular recombinant human LH (r-HLH) supplementation in women aged 35-39 years undergoing ovarian stimulation for intracytoplasmic sperm injection (ICSI). The main endpoint was the number of metaphase II oocytes retrieved. After pituitary suppression with a gonadotrophin-releasing hormone agonist, ovarian stimulation was initiated with recombinant human FSH (r-HFSH; 300-450 IU/day). On stimulation day 6, patients were randomized to receive r-HFSH alone or r-HFSH + r-HLH (r-HLH 150 IU/day) for the remainder of the stimulation period. Final follicular maturation was triggered with 250 mug of recombinant human chorionic gonadotrophin. After assessing oocyte nuclear maturity, oocyte were fertilized by ICSI and afterwards embryo quality was analyzed. Of the 131 women enrolled, 68 were allocated to r-HFSH alone and 63 to r-HFSH + r-HLH. No significant differences were observed in markers of either oocyte or embryo quality or quantity. However, higher rates of implantation and live birth per started cycle were observed with r-HLH supplementation than with r-HFSH alone. Although additional large studies are required to further investigate these findings, r-HLH supplementation for women aged 35-39 years undergoing ICSI is recommended as it may have a beneficial action on implantation.


Assuntos
Hormônio Foliculoestimulante Humano/administração & dosagem , Hormônio Luteinizante/administração & dosagem , Folículo Ovariano/fisiologia , Indução da Ovulação/métodos , Adulto , Implantação do Embrião/efeitos dos fármacos , Feminino , Fase Folicular , Humanos , Recuperação de Oócitos/métodos , Folículo Ovariano/efeitos dos fármacos , Gravidez , Resultado da Gravidez , Injeções de Esperma Intracitoplásmicas
4.
Hum Reprod ; 16(12): 2525-32, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11726569

RESUMO

BACKGROUND: Until recently, human menopausal gonadotrophin (HMG), a urinary extract containing a fixed combination of LH and FSH, was the only source of exogenous LH for women with hypogonadotrophic hypogonadism undergoing ovulation induction with gonadotrophins. Recombinant human LH (rLH) is now available for clinical use, providing a new treatment option but clinical data on its use are scanty. Therefore, the aim of the present study was to investigate the efficacy and safety of rLH combined with recombinant FSH (rFSH) to induce follicular development and ovulation in World Health Organization (WHO) group I anovulatory women. METHODS: We included in this multicentre study 38 hypogonadotrophic anovulatory (WHO group I) women. Patients received 150 IU/day rFSH and 75 IU/day rLH (with the possibility of dose adjustment) as a single s.c. injection for up to three cycles with a total of 84 treatment cycles. RESULTS: Sufficient follicular growth was observed in 79 (94%) out of 84 initiated cycles. The 75 IU rLH dose was found to be effective in most treatment cycles (94%) and only five cycles in three patients required daily dose increase. Overall, HCG was administered to trigger ovulation in 67 (80%) of the 84 cycles while it was withheld in 12 cycles (14%) due to ovarian hyper-response and five cycles (6%) were cancelled for insufficient follicular growth. The pregnancy rate per started treatment cycle and per cycle given HCG was 18 and 22.4% respectively. Pregnancy was achieved by 15 (39.5%) of the 38 patients. Mild to moderate ovarian hyperstimulation syndrome occurred in three patients. Local tolerance was good. CONCLUSIONS: This study confirms that combined rFSH and rLH treatment induces follicular growth, ovulation and pregnancy in a good proportion of hypogonadotrophic anovulatory patients and is well tolerated. The doses of 150 IU rFSH and 75 IU rLH daily seem the most appropriate but in a small minority of patients doses >75 IU rLH/day may be necessary.


Assuntos
Hormônio Foliculoestimulante/uso terapêutico , Infertilidade Feminina/terapia , Hormônio Luteinizante/uso terapêutico , Folículo Ovariano/fisiologia , Indução da Ovulação , Adulto , Anovulação/tratamento farmacológico , Anovulação/etiologia , Gonadotropina Coriônica/administração & dosagem , Feminino , Hormônio Foliculoestimulante/administração & dosagem , Hormônio Foliculoestimulante/efeitos adversos , Humanos , Hipogonadismo/complicações , Hipogonadismo/tratamento farmacológico , Hormônio Luteinizante/administração & dosagem , Hormônio Luteinizante/efeitos adversos , Síndrome de Hiperestimulação Ovariana/epidemiologia , Síndrome de Hiperestimulação Ovariana/etiologia , Gravidez , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Espanha , Organização Mundial da Saúde
5.
Rev Neurol ; 29(12): 1093-9, 1999.
Artigo em Espanhol | MEDLINE | ID: mdl-10652728

RESUMO

OBJECTIVE: The ability of natural human interferon beta (n-hIFN beta) to reduce multiple sclerosis (MS) activity was investigated in 60 patients with relapsing-remitting MS (RRMS). PATIENTS AND METHODS: Patients were randomized to receive either 9 MIU (33 micrograms) of n-hIFN beta by subcutaneous route, three times per week, on alternate days, during one year, or no treatment (control group) during the first six months and then switched to the same treatment for the following six months. Disease activity was monitored monthly by both magnetic resonance imaging (MRI) and clinical parameters. An intergroup analysis (first 6 months of the study) showed fewer active lesions and lower exacerbation rate in the treatment group than in the control group. Similarly, there were more exacerbation-free patients in the treatment group during this time. RESULTS: When switched to treatment, the control group showed a significant reduction in the number of active lesions (p = 0.00001) and the exacerbation rate decreased by half. Exacerbation-free patients more than doubled (p = 0.006) and the median time to first exacerbation was significantly prolonged (96 vs > 180 days; p = 0.019). Treatment was extended for 12 additional months at a dose of 6 MIU (22 micrograms) once a week and disease activity persisted under control in 88% of patients. Treatment with n-hIFN beta was well tolerated, adverse events being mild and self-limiting. Sera were analyzed for anti-IFN beta antibodies and neutralizing activity was found in 12% of the patients after two years. CONCLUSION: The results of this phase II study show, that n-hIFN beta promotes a significant reduction of disease activity in RRMS as shown by both MRI and clinical variables, and that the treatment is well tolerated, with low antigenicity.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Interferon beta/uso terapêutico , Esclerose Múltipla/tratamento farmacológico , Doença Aguda , Adolescente , Adulto , Anticorpos/imunologia , Progressão da Doença , Feminino , Humanos , Injeções Subcutâneas , Interferon beta/imunologia , Masculino , Pessoa de Meia-Idade , Prevenção Secundária
6.
Am J Kidney Dis ; 32(3): 454-63, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9740162

RESUMO

Recombinant human growth hormone (rhGH; Saizen, Serono, Spain) has been recently used as an anabolic agent in several catabolic states, including malnourished chronic dialysis patients. However, up-to-date, comparative studies with control groups of dialysis patients have not been reported. The aim of the present study was to assess the effects of rhGH on nutritional status in a group of malnourished adult chronic dialysis patients undergoing both continuous ambulatory peritoneal dialysis (CAPD) and hemodialysis (HD). The patients were randomly assigned to the control group (nine patients; 6 women, 3 men; mean age, 58.3 +/- 5.6 years; seven undergoing CAPD, two undergoing HD) or the rhGH group (eight patients; three women, five men; mean age, 63.9 +/- 3.1 years; four undergoing CAPD, four undergoing HD). Both groups were similar at baseline. All patients were given dietary prescriptions (35 kcal/kg/d and 1 g protein/kg ideal body weight/d) during 4 weeks. In the rhGH group, rhGH was administered at 0.2 IU/kg/d subcutaneously (SC) during this period. Anthropometric and analytic parameters were assessed before (0 weeks) therapy and at 2 and 4 weeks after starting therapy. The rhGH group showed an increase of 1.238 kg in body weight from 64.3 +/- 4.3 (mean +/- standard error of the mean [SEM]) to 65.6 +/- 4.9 kg (P < 0.05). Serum insulin-like growth factor type 1 (IGF-1) concentrations increased from 216.6 +/- 42.5 to 581.2 +/- 171.5 ng/mL (4 weeks; P < 0.01) and transferrin levels increased from 271.2 +/- 16.3 to 314.5 +/- 21.2 mg/dL (4 weeks; P < 0.05). A significant reduction in blood urea nitrogen (BUN) level was observed (62.1 +/- 1.8 v 46.8 +/- 3.8 mg/dL; 4 weeks; P < 0.05). Mean daily protein intake, determined by individual dietary survey, at 0 and 4 weeks, remained constant in both groups. In conclusion, weight gain and IGF-1 and transferrin level increases and BUN level decreases, despite the constant oral intake, suggest that short-term rhGH administration is associated with an anabolic reaction in malnourished dialysis patients.


Assuntos
Hormônio do Crescimento/uso terapêutico , Falência Renal Crônica/terapia , Diálise Peritoneal Ambulatorial Contínua , Diálise Renal , Adulto , Idoso , Nitrogênio da Ureia Sanguínea , Peso Corporal/efeitos dos fármacos , Feminino , Seguimentos , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Projetos Piloto , Transferrina/metabolismo
7.
Hum Reprod ; 12(5): 980-6, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9194651

RESUMO

The efficacy and safety of highly purified follicle stimulating hormone (FSH) associated with human chorionic gonadotrophin (HCG) was studied in 60 men with hypogonadotrophic hypogonadism. Of these men, 16 suffered from Kallmann's syndrome, 19 from idiopathic hypogonadotrophic hypogonadism and 25 from hypopituitarism. Basal testosterone concentrations were found to be far below the normal range. At baseline, 26 patients were able to ejaculate and all of them showed azoospermia, while the remaining patients were aspermic. All patients self-administered s.c. injections of FSH (150 IU x three/week) and HCG (2500 IU x two/week) for at least 6 months and underwent periodic assessments of testicular function. Testosterone concentrations increased rapidly during treatment and all but one patient reached normal values. Testicular volume showed a sustained increase reaching almost 3-fold its baseline value. At the end of treatment, 48 patients (80.0%) had achieved a positive sperm count. The maximum sperm concentration during treatment was 24.5 +/- 8.1 x 10(6)/ml (mean +/- SEM). The median time to induce spermatogenesis was 5 months. Eleven patients reported adverse events, generally not related to treatment. Three patients experienced gynaecomastia. No local reactions at injection site were observed. In conclusion, the s.c. self-administration of highly purified FSH + HCG was well tolerated and effective in stimulating spermatogenesis and steroidogenesis in these patients.


Assuntos
Gonadotropina Coriônica/uso terapêutico , Hormônio Foliculoestimulante/uso terapêutico , Hipogonadismo/tratamento farmacológico , Espermatogênese/efeitos dos fármacos , Adulto , Gonadotropina Coriônica/administração & dosagem , Gonadotropina Coriônica/farmacologia , Quimioterapia Combinada , Ejaculação/efeitos dos fármacos , Hormônio Foliculoestimulante/administração & dosagem , Hormônio Foliculoestimulante/farmacologia , Humanos , Hipogonadismo/fisiopatologia , Injeções Subcutâneas , Masculino , Prognóstico , Estudos Prospectivos , Autoadministração , Contagem de Espermatozoides/efeitos dos fármacos , Espermatogênese/fisiologia , Testículo/anatomia & histologia , Testículo/efeitos dos fármacos , Testículo/fisiologia , Testosterona/sangue , Testosterona/metabolismo , Fatores de Tempo
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