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1.
BJOG ; 125(1): 26-35, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28872775

RESUMO

BACKGROUND: Women following unilateral oophorectomy (UO) are occasionally encountered during assisted reproduction treatment. OBJECTIVE: To explore the impact of UO on ovarian reserve in assisted reproduction. SEARCH STRATEGY: An electronic database search was performed using PubMed, EBSCO, ISI, Trip, ClinicalTrial.gov and the Cochrane library followed by a manual search to identify published research between January 1978 and December 2015. SELECTION CRITERIA: Controlled studies that compared infertile women following UO undergoing IVF-ET treatment with women with two intact ovaries. DATA COLLECTION AND ANALYSIS: Two reviewers independently extracted the data concerning the impact of UO on ovarian reserve tests, ovarian response to controlled ovarian hyperstimulation and clinical pregnancy rate. Meta-analysis was performed using these measures. MAIN RESULTS: Twenty-one studies were eligible for quantitative analysis. They included 1045 and 18 172 IVF cycles in women with one and two intact ovaries, respectively. Basal FSH weighted mean difference (WMD) was significant (2.01 IU/l; 95% CI: 0.24-3.79, P = 0.026). Similarly, the WMD of serum E2 level on the day of hCG administration was significant (WMD: -431 pg/ml; 95% CI: -616 to -246, P < 0.001). However, the weighted overall odds ratio (OR) of clinical pregnancy between women with a single ovary and women with two ovaries was comparable (overall OR: 0.76; 95% CI: 0.57-1.00, P = 0.054). All eligible studies were retrospectively conducted and the heterogeneity among ovarian response measures was high. CONCLUSIONS: Available pooled data supports an adverse effect of UO on ovarian reserve involving the quantity but not the quality of the ovarian pool. TWEETABLE ABSTRACT: Review finds women with one ovary removed have less IVF capacity but the same pregnancy rate as women with two ovaries.


Assuntos
Transferência Embrionária , Fertilização in vitro , Reserva Ovariana/fisiologia , Ovariectomia/efeitos adversos , Feminino , Humanos , Infertilidade Feminina/terapia , Indução da Ovulação/métodos , Gravidez , Taxa de Gravidez
2.
J Endocrinol Invest ; 40(8): 831-839, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28290093

RESUMO

PURPOSE: To explore serum endocrine dynamics, specifically LH levels, following rLH supplementation to rFSH following GnRH-antagonist treatment in the advance reproductive age. METHODS: Women were prospectively and similarly treated employing rFSH and the flexible GnRH-antagonist protocol, while rLH was supplemented only to the study group. Serum FSH, LH, E2, and P were evaluated throughout the follicular phase. Three strategies were a priori planned to examine endocrine dynamics among women enrolled. RESULTS: While serum LH drop were similar before GnRH-antagonist stimulation, it dropped more times in the control group compared to the study group. Among women receiving rFSH only, serum LH levels dropped ≤2, ≤1 and ≤0.5 mIU/mL in 71.4, 46.4, and 28.6% of cases, while this occurred only in 38.7% (P = 0.01), 6.5% (P = 0.0004) and 3.2% (P = 0.007) of women receiving combined rFSH and rLH treatment, respectively. The same trend was found when serum LH dropped in at least two occasions following the GnRH-antagonist administration. Conversely, serum LH diagrams throughout the follicular phase did not differ between the two groups. Furthermore, individual area under the curve values of LH, E2, and P was similar between the two groups following GnRH-antagonist initiation. CONCLUSIONS: Different strategies to explore LH dynamics following the GnRH-antagonist administration have resulted in diverse results, implying the need for a consensus definition of LH threshold for adequate folliculogenesis and steroidogenesis. Such action would pave the way for understanding which groups of patients may benefit from rLH supplementation.


Assuntos
Sistema Endócrino/metabolismo , Estradiol/metabolismo , Hormônio Foliculoestimulante/metabolismo , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Antagonistas de Hormônios/uso terapêutico , Hormônio Luteinizante/administração & dosagem , Proteínas Recombinantes/administração & dosagem , Reprodução/efeitos dos fármacos , Adulto , Feminino , Fertilização in vitro , Fase Folicular/metabolismo , Humanos , Infertilidade Feminina/terapia , Indução da Ovulação , Gravidez , Estudos Prospectivos
3.
J Dairy Sci ; 97(9): 5800-5, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24952772

RESUMO

Cryptosporidium parvum is considered one of the most common enteropathogens, responsible for the high incidence of diarrhea and deleterious implications on immunity and health in neonatal calves. The pomegranate is well known for its health-promoting properties. Two experiments were designed to test the antiparasitical and antidiarrheal effects of concentrated pomegranate extract (CPE) supplement in milk in neonatal Holstein calves. Forty-one calves were randomly divided into control (n=20) and treatment (n=21) groups. For the first experiment, the treatment group was supplemented with 3.75% CPE in the daily milk ration, between 3 and 14 d of age, whereas the control group received only milk. Fecal samples were collected between d 5 and 13 to quantify Cryptosporidium oocysts, and the duration and intensity of diarrhea were evaluated. Reduced fecal oocyst count and diarrhea intensity and duration were revealed in the 3.75% CPE calves. No difference was noted in average daily gain between groups. In a second experiment, which was designed to test the effect of a lower CPE concentration (0.6% of daily milk allocation), no effects on fecal oocyst count and average daily gain were observed. However, compared with control, the lower CPE group was characterized by a shorter duration of diarrhea and higher weight gain among males at 14 d of age. These results suggest that the CPE supplement-to-calf milk ratio may potentially alleviate intestinal morbidity caused by Cryptosporidium.


Assuntos
Antiprotozoários/farmacologia , Cryptosporidium parvum/efeitos dos fármacos , Lythraceae/química , Oocistos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Ração Animal/análise , Animais , Animais Recém-Nascidos , Antidiarreicos/farmacologia , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Criptosporidiose/tratamento farmacológico , Cryptosporidium parvum/isolamento & purificação , Diarreia/tratamento farmacológico , Diarreia/parasitologia , Diarreia/veterinária , Dieta/veterinária , Suplementos Nutricionais , Fezes/parasitologia , Feminino , Masculino , Aumento de Peso
4.
Chronobiol Int ; 37(2): 189-208, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31809592

RESUMO

Ecological artificial light at night (ALAN) has been increasingly associated with negative effects on the behavior and ecology of wild birds. However, the impacts of short-term bright ALAN on the temporal biology of companion animals and the underlying mediating mechanism are unknown. We evaluated impacts of 1X60-min/middle night ALAN (200 lux, λDominant = 460 nm) nightly with or without melatonin administration on growth performance, reproductive capacity, food and water intake, and stress responses in Australian budgerigars (Melopsittacus undulatus) under captivity. 36 birds were housed in pairs under natural photoperiod and were equally divided into three groups: control, natural conditions; ALAN, control + ALAN; and melatonin, ALAN + melatonin in the drinking water during the dark period. Birds were regularly monitored for body mass, egg production, and hatchability over four months. Food intake, water consumption, and daily rhythm of fecal corticosterone were also evaluated. ALAN increased mass gain, food intake, water consumption, and drastically decreased reproductive capacity, whereas stress responses were markedly augmented. Melatonin restored food and water intake to control levels but partly reversed mass gain. Melatonin failed to ameliorate the impaired reproductive capacity despite reducing the stress responses to basal levels. These results suggest that the ALAN-induced negative impacts cannot be attributed solely to direct effects of melatonin suppression or/and exacerbated stress responses and the involvement of other photoperiodic pathway components warrant further studies. Finally, the results of our study may be of importance for improving the housing conditions of companion animals at least as concern bright ALAN exposures.


Assuntos
Melatonina , Animais , Austrália , Aves , Ritmo Circadiano , Luz , Melatonina/farmacologia , Fotoperíodo
5.
Life Sci ; 63(9): 751-7, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9740312

RESUMO

The light-dark cycle is the major time cue for daily and seasonal scheduling of physiological activities. However, non-photic cues (e.g. environmental and social constraints) may also play a significant role. A natural model exists in the golden spiny mouse (Acomys russatus) which is nocturnal when maintained alone but diurnal when sharing a habitat with its congener, the common spiny mouse (A. cahirinus). We have recently observed that the presence of A. cahirinus provokes a major change in the daily rhythms of body temperature (Tb), and urine volume without affecting the melatonin rhythm and photoperiod-induced responses. The apparent lack of interaction between the daily and photoperiodic scheduling was further investigated by studying the significance of the pineal to the modification of A. russatus daily rhythms induced by the presence of A. cahirinus. Lesion of A. russatus pineal gland resulted in diminution of urinary 6-sulfatoxymelatonin (6-SMT) and modification of Tb and urine volume rhythms. However, the modification of Tb and urine volume rhythms provoked by the presence of A. cahirinus were similar in pineal lesioned and sham-operated A. russatus. The non-photic signals released by A. cahirinus did not significantly affect glucose utilization in the suprachiasmatic nucleus of pineal- as well as sham-lesioned A. russatus. Thus, the modification of the daily scheduling of A. russatus by the photoperiod involves the pineal and/or the melatonin rhythm whereas non-photic cues effect a direct (perhaps masking), pineal-independent response to the competitor.


Assuntos
Ritmo Circadiano , Glândula Pineal/fisiologia , Animais , Temperatura Corporal , Masculino , Melatonina/análogos & derivados , Melatonina/fisiologia , Melatonina/urina , Muridae/fisiologia
6.
Oecologia ; 93(4): 518-523, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28313820

RESUMO

The effect of feeding of the mirid bug Capsodes infuscatus on fruit production of the geophyte Asphodelus ramosus was studied in a desert area in Israel. Plant and bug densities and percent loss of fruit production were measured in a relatively dry lower colluvial slope, an intermediate upper colluvial slope, and a relatively mesic wadi. Overall damage levels were very high, with 100% loss of fruit production in many plants. Within each habitat, the number of nymphs per plant clone was positively correlated with the number of ramets per clone and percent damage was positively correlated with number of nymphs per clone. However, percent damage was not correlated with number of plants per clone in any habitat. Although damage did significantly increase with plant density in the slope habitats, mean damage to fruit production per clone was lowest (50%) in the wadi where Asphodelus density was highest. As new ramets are tightly interwoven with their mother plants, occupation of new microsites depends on establishment of new clones from seeds. Therefore, the strong and density-dependent reduction in fruit production inflicted by Capsodes on the Asphodelus population on the slope has the potential to regulate the plant density in this habitat.

7.
Oecologia ; 101(3): 335-342, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28307055

RESUMO

The fruit-bat Rousettus aegyptiacus (Pteropodidae) in Israel consumes a variety of cultivated and wild fruits. The aim of this study was to explore some of its qualities as a dispersal agent for six fruit-bearing plant species. The feeding roosts of the fruit-bat are located an average of 30 m from its feeding trees and thus the bats disperse the seeds away from the shade of the parent canopy. The bat spits out large seeds but may pass some (2%) of the small seeds (<4 mg) through its digestive tract. However, neither the deposited seeds nor the ejected seeds (except in one case) had a significantly higher percentage germinating than intact seeds. Although the fruit-bat did not increase the percentage germinating, seeds of three plant species subject to different feeding behaviors (deposited in feces or spat out as ejecta) had a different temporal pattern of germination from the intact seeds. The combined seed germination distribution generated by these different treatments is more even over time than for each treatment alone. It is sugested that this increases asynchronous germination and therefore enhances plant fitness by spreading the risks encountered during germination, especially in eastern Mediterranean habitats where the pattern of rainfall is unpredictable.

8.
Oecologia ; 91(3): 365-370, 1992 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28313544

RESUMO

The spatial distribution of seedlings of the dominant perennial plant species (Pinus halepensis, Cistus salviifolius, Rhus coriaria) and may annual species was studied after a wild fire in an eastern Mediterranean pine forest. The spatial distribution of all seedlings is affected by the location of the old burned pine trees. Seedling density of Pinus and Cistus is higher at a distance from the burned pine canopy and lower near the burned pine trunk. It is also higher beneath small burned pine trees than under big ones. Rhus seedling density is higher under big burned pine trees and also near the burned trunks. Seedlings of Pinus, Cistus and Rhus growing under the burned canopy of big pine trees tend to be taller than seedlings under small ones or outside the burned canopy. Most annual species germinate and establish themselves outside the burned canopies, and only a few annual species are found beneath them. It is suggested that variation in the heat of the fire, in the amount of ash between burned pine trees of different sizes, and in the distance from the burned canopy are responsible for the observed pattern of seedling distribution. The possible ecological significance of the spatial pattern of seedlings distribution and their differential growth rate are discussed.

9.
J Chem Ecol ; 19(11): 2605-15, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24248715

RESUMO

The protein content of pulps of 26 fleshy fruit species from east Mediterranean habitats in Israel were estimated using two different methods: (1) the Kjeldahl procedure in which the total recovered nitrogen is multiplied by 6.25 to estimate total proteins, and (2) amino acid analysis by amino acid analyzer. The average protein content obtained by the Kjeldahl procedure was 5.75% (dry weight) while it was only 3.90% when amino acids were analyzed. The higher value of protein content by the Kjeldahl procedure is most likely the result of a relatively high proportion of nonprotein nitrogen compounds (31%) in these pulps. Therefore the 6.25 factor is not valid and a 4.05 factor may be more accurate for assessing the true protein content of these fleshy fruits. The data also suggest that the more accurate estimate of true protein (Y) from Kjeldahl total nitrogen (X) should be based on the highly significant linear regression between these two variables:Y=4.885X-0.6.

10.
Artigo em Inglês | MEDLINE | ID: mdl-10779728

RESUMO

The Great White Pelican Pelecanus onocrotalus is an endangered migratory bird, threatened by diminishing natural feeding sites and by persecution by fishermen. The majority of the migrating White Pelican (71000) stop-over in Israel during their autumn migration to Africa. As part of a larger study, aimed to assess the necessity of feeding during the stop-over in Israel, we examined the blood chemistry of captive and migrating White Pelicans. Blood was sampled from captive birds maintained on a fish diet, after food deprivation for 48 h and from wild birds brought from the field during migration. Food deprivation resulted in increased plasma levels of triglycerides and in lower levels of urea, potassium and calcium. In migrating birds, increased plasma levels of urea and CPK and lower levels of creatinine were revealed. In general, the coefficient of variation in the blood chemistry of migrating pelicans was higher than in the captive birds, that is to say, that these birds were in a variable physiological condition. The blood profile of migrating and wintering pelicans did not indicate a state of dehydration but did indicate energy deficiency. The less extreme changes in blood chemistry of the 48 h food-deprived compared to migrating pelicans suggest that the former did not reach a state of starvation. We conclude that for White Pelicans the stop-over in Israel is a must in order to rest and replenish their fuel reserves for completion of their autumn migration to Africa.


Assuntos
Aves/sangue , Aves/fisiologia , Animais , Dieta , Peixes , Privação de Alimentos/fisiologia , Israel
11.
J Exp Zool ; 284(1): 100-6, 1999 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10368937

RESUMO

A most important function of the circadian system is to ensure that behaviors and metabolism are appropriately timed with respect to the light/dark cycle and photoperiod. Ecological constraints can perturb the daily schedules; would they also impair photoperiodic adaptations? A natural model exists in the golden spiny mouse (Acomys russatus), which is nocturnal, but driven into diurnal activity when sharing the habitat with its congener, A. cahirinus. We show here that the presence of A. cahirinus alters the diurnal rhythms of body temperature and urine volume, delays excretion of the major melatonin metabolite, 6-sulfatoxymelatonin (6-SMT), and increases 2-deoxyglucose uptake by the suprachiasmatic nuclei in A. russatus. Nevertheless, a clear photoperiod effect on urine volume and 6-SMT rhythms was observed. These results indicate that the circadian system can adapt to major changes in daily scheduling without impairing daylength measurement, and consequently seasonal adaptation.


Assuntos
Adaptação Fisiológica , Metabolismo Energético , Melatonina/metabolismo , Muridae/fisiologia , Comportamento Social , Animais , Ritmo Circadiano , Feminino , Melatonina/análogos & derivados , Atividade Motora , Fotoperíodo , Estações do Ano , Urina
12.
J Chem Ecol ; 28(7): 1393-410, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12199503

RESUMO

This study describes the chemical ecology of a tritrophic interaction among species endemic to the island of Hawaii, USA: a tree (Sophora chrysophylla: mamane), an endangered bird (Loxioides bailleui; palila), and moth larvae (Cydia spp.). Palila and Cydia both specialize on the seed embryos of mamane but avoid eating the seed coats. Palila actively seek out and feed mamane embryos and Cydia larvae to their nestlings. Because mamane embryos contain potentially toxic levels of alkaloids, including broadly toxic quinolizidine alkaloids, and because insects often sequester alkaloids from their food plants, we focus on the questions of why palila forage upon mamane embryos and why they supplement their diet with Cydia larvae. Our data show that mamane embryos contain high amounts of potentially toxic alkaloids, but are well balanced nutritionally and contain lipids, carbohydrates, proteins, amino acids, and minerals at levels that are likely to be sufficient for maintenance and breeding. Mamane seed coats contain lower levels of alkaloids and nutrients, somewhat higher levels of phenolics, and much higher levels of nondigestible fiber. Taken together, these results suggest that palila have evolved tolerance to high levels of alkaloids and that they forage upon embryos primarily because of their availability in the habitat and high nutritional reward. Our data also suggest that Cydia are used by palila because they are readily accessible, nontoxic, and nutritious; the larvae apparently do not sequester alkaloids while feeding upon mamane seeds. Our results are interpreted with respect to the likelihood of current and historical coadaptive responses in this ecologically isolated and simplified island setting.


Assuntos
Aves , Comportamento Alimentar , Mariposas/química , Sementes/química , Sophora/química , Adaptação Fisiológica , Alcaloides/análise , Animais , Evolução Biológica , Dieta , Larva , Estado Nutricional , Reprodução , Sophora/fisiologia
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