1. The daily torpor was measured by oxygen uptake in Djungarian hamsters during adaptation to a short photoperiod (SP: 10L, 14D) at 20 degrees C. In these constant conditions the torpor presented metabolic characteristics and a daily time course independent of the duration of adaptations to SP. 2. The frequency of torpor bouts increased during SP exposure and its maximum was reached after about 130 days. The frequency of torpor was greater in males than in females. 3. The incidence of torpor was increased by constant dark exposure and this is discussed as a protective mechanism for the individual animal's ability to survive. 4. The temporal organization of daily torpor was demonstrated to be directly synchronized by the day-night cycle and to be controlled by an endogenous circadian function.

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IntroductionNumerous biological parameters are physiologically modified during normal pregnancy, in particular hematology. The knowledge of these modifications of the maternal body by biologists and clinicians allows the screening of possible anomalies. In Morocco, the reference values of the complete blood count test for pregnant woman are missing, as are those specific to different trimesters of pregnancy. The aim of this study is to look for the reference values for healthy pregnant women of the Northwest region of Morocco, to compare them to those of non-pregnant women (control) and to those of the literature.MethodsBlood samples were taken voluntarily from 3898 healthy pregnant women from 18 to 46 years old who presented themselves at the center of health Kalaa and at the service of gynecology obstetrics of the Provincial Hospital Center of M'diq (Morocco), for prenatal care. To establish the reference intervals of the CBC for non-pregnant women, a control group was constituted by 7035 healthy women from 18 to 50 years old selected according to the Moroccan law of blood donation. The CBC was measured on a Sysmex KX21N® analyzer. For each sample a systematic blood smear was done to determine the leukocyte differential.ResultsA statistically significant difference between the pregnant women and control group was noted (p < 0.05) for all the hematological parameters: red blood cells, hematocrit, hemoglobin, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, leukocytes, neutrophils, basophils, eosinophils, lymphocytes, monocytes, platelets and mean platelet volume. So, the comparison of the averages established between the first, second and third trimester of pregnancy showed the existence of a significant variation with regard to all the parameters of the CBC test looked for (p < 0.001).ConclusionThe present study provides additional baseline data for basic hematological parameters in healthy pregnant Moroccan women and concluded that pregnancy in women has the tendency to alter some hematological indices. For these reasons, there is an interest to take these modifications into account for optimal maternal and fetal medical care.

Nocturnal secretion of melatonin from the pineal gland may affect central and peripheral timing, in addition to its well-known involvement in the control of seasonal physiology. The Syrian hamster is a photoperiodic species, which displays gonadal atrophy and increased adiposity when adapted to short (winter-like) photoperiods. Here we investigated whether pineal melatonin secreted at night can impact daily rhythmicity of metabolic hormones and glucose in that seasonal species. For that purpose, daily variations of plasma leptin, cortisol, insulin and glucose were analyzed in pinealectomized hamsters, as compared to sham-operated controls kept under very long (16 h light/08 h dark) or short photoperiods (08 h light/16 h dark). Daily rhythms of leptin under both long and short photoperiods were blunted by pinealectomy. Furthermore, the phase of cortisol rhythm under a short photoperiod was advanced by 5.6 h after pinealectomy. Neither plasma insulin, nor blood glucose displays robust daily rhythmicity, even in sham-operated hamsters. Pinealectomy, however, totally reversed the decreased levels of insulin under short days and the photoperiodic variations in mean levels of blood glucose (i.e., reduction and increase in long and short days, respectively). Together, these findings in Syrian hamsters show that circulating melatonin at night drives the daily rhythmicity of plasma leptin, participates in the phase control of cortisol rhythm and modulates glucose homeostasis according to photoperiod-dependent metabolic state.

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IntroductionAmong the most useful biological examinations in common medical practice, blood count is the most prescribed. The reference intervals of the hematological parameters of this examination are of major importance for clinical orientations and therapeutic decisions. In Morocco, the reference values used by the laboratories of medical biology and used by doctors are ones collected from Caucasian and European individuals. These values could be different in the Moroccan population. Besides, reference intervals of the blood count specific to the various Moroccan regions are missing. We decided to determine the reference intervals from a population of healthy adults of the Tangier-Tetouan region by following the procedures recommended by the IFCC-CLSI guidelines in 2008 and comparing them to those of the literature.MethodsBlood samples were taken from 15840 adult volunteers (8402 men from 18 to 55 years old and 7438 women from 18 to 50 years old) from the regional transfusion center of Tangier and Tetouan during a period between November 2014 and May 2016. The complete blood count was measured by the Sysmex KX21N® analyzer. For each sample a systematic blood smear was done to determine the leukocyte differential. The data analysis was made by the software SPSS 20.0 by using percentiles 2.5th and 97.5th.ResultsA significant difference between both sexes was noted (p<0,001) for all the hematological parameters (red blood cells, hematocrit, hemoglobin, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, leukocytes, neutrophils, basophils, eosinophils, monocytes, platelets and mean platelet volume) except for the numeration of lymphocytes (p = 0.552). The values of this study were compared with those reported in Arabic, Caucasian and African populations. Said comparisons showed the existence of significant differences.ConclusionThis study tries to accentuate the necessity of proceeding with the establishment of reference intervals specific to the blood count of the Moroccan population to avoid errors of diagnosis, allow clinicians to interpret with greater specificity the hematological examinations and to improve the quality of medical care distributed to patients.

1. In Phodopus sungorus the frequency and characteristics of daily torpor were not affected by a decrease in temperature. The seasonal cycle of daily torpor is essentially under photoperiodic control. 2. Testicular regression is a necessary condition for daily torpor occurrence. Testosterone and 5 alpha-dihydrotestosterone administration totally inhibited daily torpor in hamsters which were exposed to short days. The temporal inhibition of torpor by steroids had no effect on the seasonal time measuring mechanism governing daily torpor. 3. Castration influenced certain aspects of the daily torpor display. Castrated hamsters showed a delay in terminating torpor season lending further support to the hypothesis that recrudescence of the testis plays a role in terminating the daily torpor season. Castration, when performed before or on the day of transfer to short photoperiod led to an increase in the frequency of torpor bouts and reduce SP exposure duration which is necessary for the daily torpor season beginning.

To characterize rod and cone distribution and composition in two diurnal mouse-like rodents, retinas from adult Arvicanthis ansorgei and Lemniscomys barbarus were processed for immunohistochemistry using multiple rod- and cone-specific antibodies. Antibodies tested included rhodopsin, cone opsins, pan-arrestin and cone arrestin, recoverin, and cGMP dependent ion channel. In both species, retinas were composed of approximately 33% cones, and most antibodies gave similar staining patterns. Data show these two diurnal rodents possess large numbers of cones, organised in a strict anatomical array. This suggests that diurnal rodents in general possess elevated cone numbers and could constitute valuable models for investigating cone pathophysiology.