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1.

Background

Serum anti-Mullerian hormone (AMH) is currently considered the best marker of ovarian reserve and of ovarian responsiveness to gonadotropins in in-vitro fertilization (IVF). AMH assay, however, is not available in all IVF Units and is quite expensive, a reason that limits its use in developing countries. The aim of this study is to assess whether the "ovarian sensitivity index" precisely reflects AMH so that this index may be used as a surrogate for AMH in prediction of ovarian response during an IVF cycle.

Methods

AMH serum levels were measured in 61 patients undergoing IVF with a "long" stimulation protocol including the GnRH agonist buserelin and recombinant follicle-stimulating hormone (rFSH). Patients were divided into four subgroups according to the percentile of serum AMH and their ovarian stimulation was prospectively followed. Ovarian sensitivity index (OSI) was calculated dividing the total administered FSH dose by the number of retrieved oocytes.

Results

AMH and OSI show a highly significant negative correlation (r = -0.67; p = 0.0001) that is stronger than the one between AMH and the total number of retrieved oocytes and than the one between AMH and the total FSH dose.

Conclusions

OSI reflects quite satisfactory the AMH level and may be proposed as a surrogate of AMH assay in predicting ovarian responsiveness to FSH in IVF. Being very easy to calculate and costless, its use could be proposed where AMH measurement is not available or in developing countries where limiting costs is of primary importance.  相似文献   
2.
A common characteristic of the central nervous system (CNS) neurodegenerative disorders is neuroinflammation, marked by augmented numbers of activated and primed microglia, increased inflammatory cytokines and decreased anti-inflammatory molecules. CNS neuroinflammation is a critical component in the progression of several neurodegenerative diseases which sensitize the brain to produce an exaggerated response to immune stimuli in the periphery. Neuroinflammation might initiate from the periphery and peripheral conditions through disrupted blood-brain barrier powerfully influence various brain pathologies. Gastrointestinal tract (GIT) represents a vulnerable area through which pathogens influence the brain and induce CNS neuroinflammation. The pathogens may access the CNS through blood, the nasal olfactory pathways and the GIT. Potential GI pathogens, such as Helicobacter pylori, induce humoral and cellular immune responses that, owing to the sharing of homologous epitopes (molecular mimicry), cross-react with CNS components thereby contributing and possibly perpetuating neural tissue damage. GIT is strictly connected to the CNS and a bi-directional communication exists between them. The brain is involved in regulating the immune and gut system. Conversely, limited attention has been paid on the GIT role in the development and regulation of the CNS autoimmune diseases. The GIT is the primary immune organ with specialized immunoregulatory and anti-inflammatory functions, represented by the gastrointestinal immune system (GIS). This review focuses on the potential GIS and brain dialogue implicated in neurodegenerative diseases. Gaining a better understanding of the relationship between GIS and CNS could provide an insight on the pathogenesis and therapeutic strategies of these disorders.  相似文献   
3.

Background

Numerous studies have examined the effect of psychological variables on surgical recovery, but no definite conclusion has been reached yet. We sought to examine whether psychological factors influence early surgical recovery.

Methods

We performed a systematic search in PubMed, Scopus and PsycINFO databases to identify studies examining the association of preoperative psychological variables or interventions with objectively measured, early surgical outcomes.

Results

We identified 16 eligible studies, 15 of which reported a significant association between at least one psychological variable or intervention and an early postoperative outcome. However, most studies also reported psychological factors not influencing surgical recovery and there was significant heterogeneity across the studies. Overall, trait and state anxiety, state anger, active coping, subclinical depression, and intramarital hostility appeared to complicate recovery, while dispositional optimism, religiousness, anger control, low pain expectations, and external locus of control seemed to promote healing. Psychological interventions (guided relaxation, couple support visit, and psychiatric interview) also appeared to favor recovery. Psychological factors unrelated to surgical outcomes included loneliness, perceived social support, anger expression, and trait anger.

Conclusion

Although the heterogeneity of the available evidence precludes any safe conclusions, psychological variables appear to be associated with early surgical recovery; this association could bear important implications for clinical practice. Large clinical trials and further analyses are needed to precisely evaluate the contribution of psychology in surgical recovery.  相似文献   
4.
The epitope H contains an O-linked N-acetylglucosamine residue in a specific conformation and/or environment recognized by the monoclonal antibody H (mAbH). mAbH stains two bands with Mr x10(-3) of 209 and 62 in lysates of cultured rat astrocytes. In addition, in extracts of cultured MCF-7 breast carcinoma cell line cells it stains cytokeratin 8 and five polypeptides originating from Triton X-100-soluble (Mr x10(-3) of 232, 67 and 37) and from the Triton X-100-insoluble (Mr x10(-3) of 51 and 50) fractions, respectively. In our previous studies we used the mAbH to investigate by immunostaining the expression of the epitope H in normal human brains, human brains with a variety of lesions, astrocytic tumors, infiltrating ductal breast carcinomas, fibroadenomas, and mitochondria-rich normal, metaplastic and neoplastic cells. In order to gain further insight into the expression patterns of the epitope H in human tissues we used the mAbH to investigate the immunohistochemical expression of the epitope H in normal human endometrium, including 30 cases of proliferative endometrium, 30 cases of early secretory endometrium, 30 cases of mid secretory endometrium, 30 cases of late secretory endometrium and 30 cases of decidual tissues. The main results were the following: 1) The decidual stromal cells presented in all cases high cytoplasmic expression of the epitope H; 2) The pre-decidual stromal cells presented in all cases of late secretory endometrium significant cytoplasmic expression of the epitope H ranging from moderate to high expression; 3) The non pre-decidual stromal cells of the functional endometrial layer presented in all cases insignificant cytoplasmic expression of the epitope H ranging from null to low expression; 4) The stromal cells of the basal layer of the endometrium and decidua did not express the epitope H in any case; 5) The endometrial stromal granulocytes did not express the epitope H in any case and 6) The blood vessel wall cells (endothelial and smooth muscle) of the endometrium through the whole duration of the menstrual cycle and of the decidua presented high cytoplasmic expression of the epitope H. It is concluded that decidualized and pre-decidualized human normal endometrial stromal cells show increased expression of the O-linked N-acetylglucosamine containing epitope H compared to non-decidualized endometrial stromal cells. These findings suggest that the expression of the epitope H may be under positive progesteronic control in normal human endometrium. Further investigation of the antigens bearing the epitope H might help to gain further insight into the histophysiology and the pathology of human endometrium.  相似文献   
5.
SU11248 sunitinib malate sutent® is a selective inhibitor of certain protein tyrosine kinases including VEGF-R types 1–3 PDGF-R-a and -b, c-kit, and RET. Its antitumor activity may result from both inhibition of angiogenesis and direct antiprofilerative effects on certain tumor types. In several phase I/II/III studies, sutent® was found to be effective as second and first line treatment in metastatic renal cell carcinoma (RCC). In fact, with a 37% response rate and an additional 48% stable disease sutent became the drug of choice for first line treatment in RCC. Sutent® was also effective as second line treatment in patients with gastrointestinal stromal tumors (GIST) with 8% response rate, 70% stable disease and a 20-month median survival. Prolonged stable disease was also documented in neuroendocrine tumors. In addition, a phase II study in multitreated women with breast cancer, sutent® demonstrated a moderate activity with 16% clinical benefit. Finally, in non-small cell lung cancer (NSCLC) in patients’ progressing on chemotherapy sutent® was able to achieve a 10% response rate, a level of activity similar to those documented by other agents approved for lung cancer. The agent is being tested in other tumors with a modified schedule of dosage.  相似文献   
6.
7.
Risedronate and teriparatide have opposite actions on the osteoblast-osteoclast dipole and are expected to influence the RANK/RANKL/osteoprotegerin (OPG) system. We aimed to evaluate changes in serum OPG and RANKL after risedronate or teriparatide administration in postmenopausal osteoporotic women. Seventy-four postmenopausal Caucasian women (age 64.1+/-1.0 years) were studied. Women with osteopenia served as controls (group 1, n=30). Women with osteoporosis were randomly assigned to either risedronate 35 mg once weekly (group 2, n=21) or teriparatide 20 microg once daily (group 3, n=23) for six months. Blood samples for serum RANKL, OPG, N-terminal propeptide of type 1 collagen (P1NP), and C-terminal telopeptide of type 1 collagen (CTx) were obtained before treatment and three and six months after treatment. P1NP and CTx levels remained unchanged in group 1, decreased in group 2 (p<0.001), and increased in group 3 women (p<0.001) throughout the treatment. OPG levels remained unchanged while RANKL decreased gradually in all groups (p<0.001). There was no correlation between OPG or RANKL and P1NP or CTx. Our data suggest that neither antiresorptive nor osteoanabolic therapy causes specific alterations of serum OPG/RANKL levels; therefore, these cytokines cannot substitute for the established markers of bone turnover in the monitoring of response to osteoporosis treatment.  相似文献   
8.
9.
The reversed cubic phases (QII) are a class of self-assembled amphiphile–water structures that are rich in diversity and structural complexity. These nanostructured liquid crystalline materials are generating much interest owing to their unique surface morphology, biological relevance and potential technological and medical applications. The structure of QII phases in binary amphiphile–water systems is affected by the molecular structure of surfactant, water content, temperature and pressure. The presence of additives also plays an important role. The structure and phase behaviour of ternary QII phases, which are comprised of two miscible amphiphiles and water, significantly differ from the binary system alone. The modulation of the phase behaviour through the addition of a second amphiphile offers an opportunity to control the size and shape of the nanostructures using a ‘bottom-up’ approach. In this mini-review, we discuss the structure of reversed cubic phases of amphiphile–water systems and highlight the modulation of cubic-phase structure in ternary-phase systems. We also extend this review to bulk cubic phases and the corresponding nanoscale dispersions, cubic-phase nanoparticles.  相似文献   
10.
Paul  REL  Lafond  T  Müller-Graf  CDM  Nithiuthai  S  Brey  PT  Koella  JC 《BMC evolutionary biology》2004,4(1):1-13

Background

Theoretical studies suggest that direct and indirect selection have the potential to cause substantial evolutionary change in female mate choice. Similarly, sexual selection is considered a strong force in the evolution of male attractiveness and the exaggeration of secondary sexual traits. Few studies have, however, directly tested how female mate choice and male attractiveness respond to selection. Here we report the results of a selection experiment in which we selected directly on female mating preference for attractive males and, independently, on male attractiveness in the guppy, Poecilia reticulata. We measured the direct and correlated responses of female mate choice and male attractiveness to selection and the correlated responses of male ornamental traits, female fecundity and adult male and female survival.

Results

Surprisingly, neither female mate choice nor male attractiveness responded significantly to direct or to indirect selection. Fecundity did differ significantly among lines in a way that suggests a possible sexually-antagonistic cost to male attractiveness.

Conclusions

The opportunity for evolutionary change in female mate choice and male attractiveness may be much smaller than predicted by current theory, and may thus have important consequences for how we understand the evolution of female mate choice and male attractiveness. We discuss a number of factors that may have constrained the response of female choice and male attractiveness to selection, including low heritabilities, low levels of genetic (co)variation in the multivariate direction of selection, sexually-antagonistic constraint on sexual selection and the "environmental covariance hypothesis".
  相似文献   
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