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1.
Evidence exists that the functional differences between the left and right cerebral hemispheres are affected by age. One prominent hypothesis proposes that frontal activity during cognitive task performance tends to be less lateralized in older than in younger adults, a pattern that has also been reported for motor functioning. Moreover, functional cerebral asymmetries (FCAs) have been shown to be affected by sex hormonal manipulations via hormone therapy (HT) in older women. Here, we investigate whether FCAs in fine motor coordination, as reflected by manual asymmetries (MAs), are susceptible to HT in older women. Therefore, sixty-two postmenopausal women who received hormone therapy either with estrogen (E) alone (n = 15), an E-gestagen combination (n = 21) or without HT (control group, n = 26) were tested. Saliva levels of free estradiol and progesterone (P) were analyzed using chemiluminescence assays. MAs were measured with a finger tapping paradigm consisting of two different tapping conditions. As expected, postmenopausal controls without HT showed reduced MAs in simple (repetitive) finger tapping. In a more demanding sequential condition involving four fingers, however, they revealed enhanced MAs in favour of the dominant hand. This finding suggests an insufficient recruitment of critical motor brain areas (especially when the nondominant hand is used), probably as a result of age-related changes in corticocortical connectivity between motor areas. In contrast, both HT groups revealed reduced MAs in sequential finger tapping but an asymmetrical tapping performance related to estradiol levels in simple finger tapping. A similar pattern has previously been found in younger participants. The results suggest that, HT, and E exposure in particular, exerts positive effects on the motor system thereby counteracting an age-related reorganization.  相似文献   

2.
DHEA-S treatment is used as an anti-aging and anti-obesity hormone therapy in adults; however, it mechanisms of action are not clearly elucidated.The objective of the present work was to analyze the effect of a replacement therapy, which included a daily single oral dose of DHEA-S for three months, on the composition of human plasma fatty acids (FAs) in obese women.In the first study, a randomized, double-blind, placebo-controlled trial was conducted involving 61 postmenopausal women, who were assigned to receive 100 mg/day of DHEA-S (n = 41) or placebo (n = 20) orally for 3 months. In a second study, the effect of DHEA-S treatment on postmenopausal obese women (n = 41) was compared to that in premenopausal obese women (n = 20). Blood samples were collected at the beginning and at the end of the treatment. Plasma FAs were analyzed by gas chromatography.DHEA-S treatment produced significant changes in plasma FAs of both post- and premenopausal women with a reduction of total saturated FAs (SFA) as well as an increase in n − 6 polyunsaturated FA (PUFA). Particularly, in premenopausal women the DHEA-S treatment also increased the plasma n − 3 PUFA percentage. Regarding estimation of desaturase activity, our data showed that Δ6-desaturase was significantly decreased in postmenopausal women after DHEA-S treatment, whereas Δ5-desaturase was increased in the premenopausal group.In conclusion, DHEA-S treatment in obese women modifies plasma FA composition towards a potentially better metabolic profile, mainly by decreasing SFA and increasing n − 6 PUFA in both postmenopausal and premenopausal women.  相似文献   

3.
Several studies have reported that performance on spatial rotation tests is better at menses than at high estradiol phases of the menstrual cycle in women. These effects are debated because nearly all reports of menstrual cycle variability have relied on a single test, the Mental Rotations Test (MRT, Vandenberg and Kuse, 1978). In the present study, we investigated key features of the MRT that might be responsible for its association with estradiol levels. We hypothesized that associations could be demonstrated for other tasks that share the same characteristics. Forty-four women ages 20–38 years, matched on education and general ability, were assessed at low (n = 24) or high (n = 20) estradiol stages of the menstrual cycle on a set of spatial tests that varied in dimensionality, plane of rotation, angular disparity, and effortfulness. Saliva was used to quantify estradiol and progesterone. Low estradiol was found to be associated with significantly better accuracy on the MRT and also on a mental rotation task that required large angles of rotation but employed only two-dimensional object representations and rotations limited to the picture plane. In contrast, a task using identical stimuli that required only small angles of rotation did not show an estradiol effect. A group difference also was seen on a test of perceptual closure. The results confirm that the estradiol effect is not limited to the MRT, and identify the rotational element, but also aspects of figural perception, as possible processes that may be responsive to estrogens. These findings advance our understanding by showing an association between estradiol and discrete spatial processes. Implications for understanding the origins of the robust sex difference commonly observed on the MRT are discussed.  相似文献   

4.
Sex differences in electroencephalographic (EEG) correlates of creativity were studied using verbal and figural divergent tasks to be performed in accordance with the instructions to “give any solution” or “give an original solution.” The common effect was a greater activity of the right hemisphere, which did not depend on the sex, task type, or instructions for performance of the tasks. The α2 and β2 rhythms were the main EEG frequency correlates of creative thinking; the degree and sign of their reactivity depended on the aforementioned factors. Although the creative abilities in men and women were similar under test conditions, the EEG correlates of both figural and verbal tasks were sex-dependent. A high reactivity of the α2 rhythm was more marked during verbal creative thinking in women; and that of the β2 rhythm, during figural creative thinking in men. The instruction-related improvement of the critical selection of solutions was to a greater extent reflected by changes in the cortical activity, more pronounced in the frontal cortex in the women. Thus, the same creative productivity in men and women was mediated by different strategies of performance of both figural and verbal tasks, and the sex-related differences in these strategies remained even when the motivation for creativity was changed.  相似文献   

5.
An ovulatory follicular wave was induced by ablation of follicles ≥6 mm and treatment with prostaglandin F2α (PGF) on Day 10 (ovulation = Day 0). Follicle and hormone dynamics of the induced waves were compared among three age groups: young (5-6 y, n = 14 waves), intermediate (10-14 y, n = 16), and old (≥18 y, n = 15). During the common-growth phase of the induced wave (Days 12-17), diameter of the future ovulatory follicle was not different among ages, but the young group had more (P < 0.05) follicles that reached ≥10 mm. The number was correlated (r = +0.7; P < 0.0001) within mares between consecutive interovulatory intervals, indicating repeatability. Concentrations of LH increased in all age groups during Days 12-17, but were greatest (P < 0.002) in the young group and continued to be greater (P < 0.0001) throughout the ovulatory LH surge. During several days before Day −1, there were no age-related effects on systemic estradiol concentrations, diameter of the preovulatory follicle, or B-mode echo texture or color-Doppler signals of blood flow in the follicle wall. Interpretations were: (1) greater number of follicles in the young group reflected a greater follicle reserve, (2) greater LH concentrations throughout the ovulatory surge in the young group reflected a more positive response to an extraovarian/environmental influence after removal of the negative effect of progesterone, and (3) lower LH concentrations in the older groups were adequate for the preovulatory changes in the follicle.  相似文献   

6.
The presence of a thin endometrium has an important role in allowing the best conditions for hysteroscopic surgery. Here, we explored the efficacy of a 14-day administration of nomegestrol acetate, a progestogen with high progestogen potency effects, in rapid endometrial preparation to operative hysteroscopy.A total of 86 fertile women selected for operative hysteroscopy received for 14 days either 5 mg day−1 of nomegestrol acetate (n = 43; group A) or 4 mg day−1 of folic acid (n = 43; group B), starting on day 1 of the subsequent menstrual cycle. Before treatments on days 12-14 of the menstrual cycle, all patients underwent endometrial thickness measurement; ultrasonography of the ovaries to measure the appearance of a dominant follicle; diagnostic hysteroscopy with endometrial biopsy; plasma estradiol (E2), progesterone (P), luteinising hormone (LH) and follicle-stimulating hormone (FSH) levels measurements. On the day of surgery, patients repeated endometrial and ovarian ultrasonography and, E2, P, LH and FSH measurement.At enrolment, endometrial thickness, mean follicular diameter and E2, P, LH and FSH concentrations did not differ between groups. At the time of operative hysteroscopy (i.e., after 14 days’ treatment) group A, but not group B, showed significant (all P < 0.001) reduction of endometrial thickness, mean diameter of dominant follicle, E2, P and LH concentrations. Endometrial preparation was judged more effective in group A than B, since the endometrial mucosa in all of the women of group A appeared to be very thin, hypotrophic, regular and pale. In conclusion, administration of nomegestrol acetate was effective in reducing endometrial thickness, also acting on the hypothalamus-pituitary-ovarian axis, thus allowing highly favourable operative hysteroscopic conditions.  相似文献   

7.
Kisspeptin, the product of the hypothalamic KISS1 gene, is a main regulator of the hypothalamic-pituitary-gonadal axis and could be a link between metabolism and reproduction through its interaction with leptin. Kisspeptin could be involved in gonadotropin regulation and responsive to leptin levels from the first stages of life, exhibiting, as does leptin, sexual dimorphism. To test our hypothesis, we have analyzed plasma kisspeptin levels and their possible relationship with gonadotropins and leptin in a cohort composed of newborns (n = 86) and adults (n = 55). Plasma kisspeptin, gonadotropin and leptin levels were measured by RIA and multiplexed bead immunoassays, respectively. We have built a multivariate linear regression model (analyzing kisspeptin and LH separately as dependent variables) by stepwise analysis, incorporating the variables that had shown significant correlation in the univariate analysis. Cord blood samples exhibited high kisspeptin levels 127.01(113-141.02 pmol/l), but these were not sexually dimorphic. The adult population exhibited sexual dimorphism (3.72(2.95-4.49) vs. 1.77(1.23-2.31) pmol/l women vs. men, p < 0.05). Leptin levels showed sexual dimorphism in cord blood samples and also in the adult population. Furthermore, there was a significant interaction between LH and kisspeptin levels and kisspeptin was negatively correlated with age. The high kisspeptin levels observed in cord blood, with no sexual dimorphism, suggest a placental source. The sexual dimorphism exhibited in adulthood supports the notion that there are different sources and/or differential kisspeptin regulation between men and women.  相似文献   

8.
Social relationships in domestic fowl are commonly assumed to rely on social recognition and its pre-requisite, discrimination of group-mates. If this is true, then the unnatural physical and social environments in which commercial laying hens are typically housed, when compared with those in which their progenitor species evolved, may compromise social function with consequent implications for welfare. Our aims were to determine whether adult hens can discriminate between unique pairs of familiar conspecifics, and to establish the most appropriate method for assessing this social discrimination. We investigated group-mate discrimination using two learning tasks in which there was bi-directional exchange of visual, auditory and olfactory information. Learning occurred in a Y-maze task (p < 0.003; n = 7/8) but not in an operant key-pecking task (p = 0.001; n = 1/10). A further experiment with the operant-trained hens examined whether failure was specific to the group-mate social discrimination or to the response task. Learning also failed to occur in this familiar/unfamiliar social discrimination task (p = 0.001; n = 1/10). Our findings demonstrate unequivocally that adult laying hens kept in small groups, under environmental conditions more consistent with those in which sensory capacities evolved, can discriminate group members: however, appropriate methods to demonstrate discrimination are crucial.  相似文献   

9.
《Hormones and behavior》2011,59(5):929-935
Prior research shows that menopause is associated with changes in cognition in some older women. However, how estrogen loss and subsequent estrogen treatment affects cognition and particularly the underlying brain processes responsible for any cognitive changes is less well understood. We examined the ability of estradiol to modulate the manipulation of information in working memory and related brain activation in postmenopausal women. Twenty healthy postmenopausal women (mean age (SD) = 59.13 (5.5)) were randomly assigned to three months of 1 mg oral 17-β estradiol or placebo. At baseline and three months later each woman completed a visual verbal N-back sequential letter test of working memory during functional magnetic resonance imaging (fMRI). The fMRI data showed that women who were treated with estradiol for three months had increased frontal activation during the more difficult working memory load conditions compared to women treated with placebo. Performance on the verbal working memory task showed no difference between estradiol and placebo treated subjects. These data are consistent with prior work showing increases in frontal activation on memory tasks after estrogen treatment. However, this is the first study to show that estrogen-induced increases in brain activity were tied to cognitive load during a verbal working memory task. These data suggest that estradiol treatment effects on cognition may be in part produced through modulation of frontal lobe functioning under difficult task conditions.  相似文献   

10.
Negative childhood family environments have been associated with stress-related physical and psychological health consequences across the lifespan. The present study examined the relation between adverse relationships in the family of origin and physiological stress response, as measured by salivary cortisol, in emerging adulthood. Seventy-six university students (age range = 18-22) selected from intact married families-of-origin characterized by either negative (n = 39) or positive (n = 37) relationship quality engaged in a challenging role play task. Results from multilevel models indicated that those from negative families exhibited significantly lower salivary cortisol across the task than those from positive families. This relation did not change in strength or direction after controlling for experiences with abuse or recent anxiety or depressive symptoms. These findings suggest the significance of early family relationships on the long-term activity of the HPA axis.  相似文献   

11.
Copper(I) cyanide reacts with various liquid amines and sulfides (L) under solvent-less conditions to form (CuCN)Ln, n = 0.5, 0.57, 0.75, 0.8, 1, 1.25, 1.5, 2. New X-ray structures are reported for L = Py (Py = pyridine, n = 0.57), 2-MePy (n = 1), 3-EtPy (n = 1.5), 2-ClPy (n = 1), 3-ClPy (n = 2), 3-MeOPy (n = 2), 4-tBuPy (n = 1.5), piperidine (n = 1.25), N-methylmorpholine (n = 1), N,N-dimethylcyclohexylamine (n = 1), 1-methylimidazole (n = 3), Me2S (n = 1), and tetrahydrothiophene (n = 1). The amine structures (except for the monomeric 1-methylimidazole complex) reveal 1D CuCN chains decorated with 0-2 L per metal atom. Chain structures observed include zigzag, helical and figure-8 helical. The CuCN-sulfide structures show sulfur-bridging of CuCN chains. In some cases (CuCN)L?1.5 species are transformed to (CuCN)L under vacuum. Thermal analysis shows facile release of ligand, yielding CuCN. Most of the (CuCN)Ln products are photoluminescent, emitting in the visible region. In some cases, coordination of very similar amines results in remarkably different emission spectra.  相似文献   

12.

Background

In neuropsychiatric diseases with basal ganglia involvement, higher cognitive functions are often impaired. In this exploratory study, we examined healthy young adults to gain detailed insight into the relationship between basal ganglia volume and cognitive abilities under non-pathological conditions.

Methodology/Principal Findings

We investigated 137 healthy adults that were between the ages of 21 and 35 years with similar educational backgrounds. Magnetic resonance imaging (MRI) was performed, and volumes of basal ganglia nuclei in both hemispheres were calculated using FreeSurfer software. The cognitive assessment consisted of verbal, numeric and figural aspects of intelligence for either the fluid or the crystallised intelligence factor using the intelligence test Intelligenz-Struktur-Test (I-S-T 2000 R). Our data revealed significant correlations of the caudate nucleus and pallidum volumes with figural and numeric aspects of intelligence, but not with verbal intelligence. Interestingly, figural intelligence associations were dependent on sex and intelligence factor; in females, the pallidum volumes were correlated with crystallised figural intelligence (r = 0.372, p = 0.01), whereas in males, the caudate volumes were correlated with fluid figural intelligence (r = 0.507, p = 0.01). Numeric intelligence was correlated with right-lateralised caudate nucleus volumes for both females and males, but only for crystallised intelligence (r = 0.306, p = 0.04 and r = 0.459, p = 0.04, respectively). The associations were not mediated by prefrontal cortical subfield volumes when controlling with partial correlation analyses.

Conclusions/Significance

The findings of our exploratory analysis indicate that figural and numeric intelligence aspects, but not verbal aspects, are strongly associated with basal ganglia volumes. Unlike numeric intelligence, the type of figural intelligence appears to be related to distinct basal ganglia nuclei in a sex-specific manner. Subcortical brain structures thus may contribute substantially to cognitive performance.  相似文献   

13.
The present study aimed to assess the efficacy of reduced doses of cloprostenol for synchronizing estrus and ovulation in hair sheep. With the aim to evaluate the luteolytic activity of reduced cloprostenol doses, a first experiment was performed using a relatively large (group H: 126 μg; n = 8), medium (group M: 68.25 μg; n = 6) and small (group L: 38.5 μg; n = 6) cloprostenol dose. Luteolysis was assessed at Days 3 and 6 after injection (Day 0) by progesterone concentrations (P4) and transrectal ultrasonography (US). In Experiment 2, sheep were randomly assigned to the same three doses to evaluate a protocol for estrous synchronization using two injections administered 9 days apart. A third trial was performed with ewes treated (9 days apart) with the large dose (H = 126 μg; n = 12) and with a small dose adjusted for facilitating volume management (LA = 43.75 μg; n = 12). Presence of estrous cycling was determined in all the ewes by US and P4 assay, at Days −9, −6, −2, 0 (Day of second cloprostenol injection), 8 and 11. Bleeding and US were done every 4 h from 16 h of the beginning of the estrus during the third trial to assess the preovulatory LH surge and timing of ovulation. Additionally, blood samples were drawn at Days 0, 1, 2 and 3 to assess estradiol (Experiments 2 and 3) and P4 (Experiment 2) concentrations during the ovarian follicular phase. In all experiments, percentage of animals showing luteolysis, preovulatory follicular dynamics and function and percentage of ewes showing behavioral estrus in response to treatment was similar among groups. Timing of estrus for group H was earlier than group L (28.6 ± 1.8 h compared with 37.1 ± 2.4 h; P < 0.05). In the third trial, the preovulatory LH peak was higher in the LA group than group H, in terms of maximum mean concentration during the surge (27.7 ± 1.8 ng/mL compared with 21.3 ± 2.2 ng/mL; P < 0.05) and area under the curve (AUC; 183.4 ± 12.7 ng/mL compared with 127.7 ± 10.9 ng/mL; P < 0.01). However, timing of ovulation was similar for H and LA groups. Thereafter, ovulation rate and luteal function at Day 11 were similar. Current results demonstrate that reduced doses of cloprostenol may be applied in a practical manner for reproductive management of sheep, with the additional advantage of reducing treatment costs.  相似文献   

14.
To compare frequency and functional activity of peripheral blood (PB) Th(c)17, Th(c)1 and Treg cells and the amount of type 2 cytokines mRNA we recruited SLE patients in active (n = 15) and inactive disease (n = 19) and healthy age- and gender-matched controls (n = 15). The study of Th(c)17, Th(c)1 and Treg cells was done by flow cytometry and cytokine mRNA by real-time PCR. Compared to NC, SLE patients present an increased proportion of Th(c)17 cells, but with lower amounts of IL-17 per cell and also a decreased frequency of Treg, but with increased production of TGF-β and FoxP3 mRNA. Ιn active compared to inactive SLE, there is a marked decreased in frequency of Th(c)1 cells, an increased production of type 2 cytokines mRNA and a distinct functional profile of Th(c)17 cells. Our findings suggest a functional disequilibrium of T-cell subsets in SLE which may contribute to the inflammatory process and disease pathogenesis.  相似文献   

15.
16.

Aims

Asymmetric dimethylarginine (ADMA) is an endogenous competitive inhibitor of nitric oxide (NO) synthase, an enzyme responsible for the generation of NO. Plasma concentrations of ADMA increase in the elderly and in postmenopausal women. In fact, an elevated ADMA level is a risk factor of cardiovascular disease. Aerobic exercise has a beneficial effect on cardiovascular disease. However, the relationship between ADMA and aerobic fitness is unknown. The aim of this study was to determine whether plasma ADMA concentrations correlate with aerobic fitness levels in postmenopausal women.

Main methods

Thirty healthy postmenopausal women aged 50–76 years participated in this study. We measured plasma concentrations of ADMA and oxygen consumption at the ventilatory threshold (VO2VT) as an index of aerobic fitness. Subjects were divided into the low aerobic fitness (Low fitness) and high aerobic fitness (High fitness) groups, and the dividing line was set at the median VO2VT value.

Key findings

VO2VT was significantly higher in the High fitness group than in the Low fitness group (P < 0.01). The plasma ADMA concentrations in the High fitness group were significantly lower than those in the Low fitness group (P < 0.05). There was a negative correlation between plasma ADMA concentrations and VO2VT (r = − 0.532, P < 0.01).

Significance

We found that plasma ADMA concentrations were associated with aerobic fitness in postmenopausal women. The results of this study suggest that habitual aerobic exercise may decrease plasma ADMA concentrations.  相似文献   

17.
Previously we demonstrated that pre-ovulatory LH and post-ovulatory progesterone (P4) concentrations in plasma were low and embryo development was retarded when sows were induced to ovulate during lactation by submitting them to intermittent suckling (IS). The present study investigated whether this was due to: (1) stage of lactation when IS was initiated, and (2) continuation of IS post-ovulation. Multiparous Topigs40 sows were studied under three conditions: conventional weaning at Day 21 of lactation (C21; n = 30), intermittent suckling from Day 14 of lactation (IS14; n = 32), and intermittent suckling from Day 21 of lactation (IS21; n = 33). Sows were separated from piglets for 12 h daily during IS. IS sows were either weaned at ovulation or 20 d following ovulation. One-third (21/63) of the IS21 and C21 sows had already ovulated or had large pre-ovulatory follicles at Day 21 and were excluded from further study. Initiation of IS at Day 14 instead of Day 21 of lactation tended to reduce P4 at 7 d post-ovulation (P = 0.07), did not affect pregnancy rate, and tended to reduce embryo survival (P = 0.06). Continuation of IS during pregnancy resulted in lower P4 at 7 and 12 d post-ovulation, tended to reduce embryo weight and pregnancy rate (P < 0.10), whereas embryo survival was not affected. This study presents data for a population of sows in which follicle growth and ovulation are easily triggered under suckling conditions. Further, when these sows are bred during lactation, initiation of IS at 21 rather than 14 d of lactation with weaning at ovulation yields the most desirable reproductive performance.  相似文献   

18.
Hybrid density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations have been carried out for ozone-water clusters O3(H2O)n (n = 1-4) in order to obtain hydration effects on the absorption spectrum of ozone. The first water molecule in n = 1 is bound to the ozone molecule by an oxygen orientation form in which the oxygen atom of H2O orients the central oxygen atom of O3. In n = 2, the water dimer is bound to O3 and then the cyclic structure is formed as the most stable structure. For n = 3 (or n = 4), the cyclic water trimer (or tetramer) is bound by a hydrogen bond to the ozone molecule. The TD-DFT calculations of O3(H2O)n (n = 0-4) show that the first and second excitation energies of O3 are blue-shifted by the interaction with the water clusters. The magnitude of the spectral shift is largest in n = 2, and the shifts of the excitation energies are +0.07 eV for S1 and +0.13 eV for S2 states. In addition to the spectral shifts (S1 and S2 states), it is suggested that a charge-transfer band is appeared as a low-lying excited state above the S1 and S2 states. The origin of the spectrum shifts was discussed on the basis of theoretical results.  相似文献   

19.
After menopause, critically estrogen low levels result in modifications in vaginal wall. This cross-sectional study aims to determine whether there is a change in the number of vessels in the lamina propria of the vagina after menopause in parallel to the ER-alpha expression on the vaginal wall. Twelve women who underwent a genital surgery for genital prolapse up to grade II were selected. They were divided into two groups: a premenopausal group (PG) consisting of six women who were 18–40 years old with FSH levels =12 mIU/ml and regular cycles, and a menopausal group (MG) consisting of six women at least one year after menopause who were <65 years old with FSH levels =40 mIU/ml. Slides were stained for ER-alpha immunohistochemistry, and an endothelial cell marker CD3 was used to label vessels which were identified by using a system for morphometry. The number of vessels was significantly higher in the PG than in the MG both on the anterior wall (PG: 1.055 ± 145.8 vessels/mm2, MG: 346.6 ± 209.9 vessels/mm2, p < 0.0001) and on the posterior wall (PG: 1064 ± 303.3 vessels/mm2, MG: 348.6 ± 167.3 vessels/mm2, p = 0.0005). The ER-alpha score was significantly higher in the PG than the score for the MG on both the anterior and posterior walls (PG: 6.0 ± 0.52, MG: 2.5 ± 0.89, p = 0.007; PG: 5.8 ± 0.79, MG: 2.7 ± 0.95, p = 0.03, respectively). There was a positive correlation between the ER-alpha score and the vessel concentration on the anterior (r = 0.6656, p = 0.018) and posterior (r = 0.6738, p = 0.016) vaginal walls. Age was strongly negatively correlated with vessel concentration on the vaginal walls (respectively r = -0.9033, p < 0.0001, r = -0.7440, p = 0.0055). Therefore, postmenopausal women with genital prolapse have a smaller number of vessels on the vaginal wall compared to normoestrogenic controls with the same pathological condition. Hypoestrogenism and advancing age are factors that are associated to these changes.  相似文献   

20.
The full length surface antigen 2 (SAG2) gene of the protozoan parasite Toxoplasma gondii was cloned and intracellularly expressed in the Pichia pastoris expression system. The molecular weight of the expressed recombinant SAG2 (36 kDa) was much larger than the native SAG2 (22 kDa). This discrepancy in size was due to hyperglycosylation, as deglycosylation assay reduced the size of the recombinant SAG2 to 22 kDa. Despite being hyperglycosylated, the recombinant SAG2 reacted strongly with pooled anti-Toxoplasma human serum, pooled anti-Toxoplasma mouse serum and a SAG2-specific monoclonal antibody. The glycosylated recombinant SAG2 was further evaluated in Western blot and in-house enzyme-linked immunosorbent assay (ELISA) using 80 human serum samples, including confirmed early acute (IgM positive, IgG negative; n = 20), acute (IgM positive, IgG positive; n = 20) and chronic (IgM negative, IgG positive; n = 20) toxoplasmosis patients, and toxoplasmosis negative control patients (n = 20). Results of the Western blot showed that the recombinant SAG2 reacted with all 60 samples of the toxoplasmosis cases but not with the Toxoplasma-negative samples. The sensitivity of in-house ELISA was 80%, 95% and 100% for early acute, acute and chronic patients’ serum samples, respectively. Vaccination study showed that serum from mice immunised with the glycosylated recombinant SAG2 reacted specifically with the native SAG2 of T. gondii. The mice were significantly protected against lethal challenge with live T. gondii RH strain tachyzoites (P < 0.01) and their survival time was increased compared to controls. Therefore, the present study shows that the P. pastoris-derived recombinant SAG2 was specific and suitable for use as antigen for detecting anti-Toxoplasma IgG and IgM antibodies. The vaccination study showed that recombinant SAG2 protein was immunoprotective in mice against lethal challenge.  相似文献   

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