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91.

Background:

Nulliparity is an endometrial cancer risk factor, but whether or not this association is due to infertility is unclear. Although there are many underlying infertility causes, few studies have assessed risk relations by specific causes.

Methods:

We conducted a pooled analysis of 8153 cases and 11 713 controls from 2 cohort and 12 case-control studies. All studies provided self-reported infertility and its causes, except for one study that relied on data from national registries. Logistic regression was used to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI).

Results:

Nulliparous women had an elevated endometrial cancer risk compared with parous women, even after adjusting for infertility (OR=1.76; 95% CI: 1.59–1.94). Women who reported infertility had an increased risk compared with those without infertility concerns, even after adjusting for nulliparity (OR=1.22; 95% CI: 1.13–1.33). Among women who reported infertility, none of the individual infertility causes were substantially related to endometrial cancer.

Conclusions:

Based on mainly self-reported infertility data that used study-specific definitions of infertility, nulliparity and infertility appeared to independently contribute to endometrial cancer risk. Understanding residual endometrial cancer risk related to infertility, its causes and its treatments may benefit from large studies involving detailed data on various infertility parameters.  相似文献   
92.
NRAS mutations occur in 3–5% of colorectal cancer. Differently from KRAS and BRAF mutations, the role of NRAS mutations as prognostic and predictive markers in metastatic colorectal cancer (mCRC) has been investigated to a lesser extent. A retrospective series suggested the role of NRAS mutations as predictors of resistance to anti‐EGFR monoclonal antibodies (MoAbs) in chemo‐refractory patients with mCRC. In our study, KRAS codons 12, 13, 61 and BRAF codon 600 mutational status were evaluated in mCRCs referred to our Institution from 2009 to 2012. NRAS codons 12, 13 and 61 mutational status was analyzed in KRAS/BRAF wt patients. We collected pathological and clinical features in the overall population and outcome data in a subset of NRAS mutated chemo‐refractory patients treated with anti‐EGFR MoAbs in advanced lines. NRAS was mutated in 47/786 (6%) mCRCs. NRAS and KRAS mutated tumors did not show significant differences in terms of clinical and pathological characteristics, except for a lower prevalence of mucinous histology (p = 0.012) and lung metastases (p = 0.012) among NRAS mutated tumors. In the uni‐ and multivariate model, NRAS mutations were associated with shorter overall survival (OS) compared to all wt patients (median OS 25.6 vs 42.7 months; univ: HR = 1.91, 95% CI 1.39–3.86, p = 0.0013; multiv: HR = 1.75, 95% CI 1.1.3–2.72, p = 0.013). None of the chemo‐refractory NRAS mutated patients evaluable for response to anti‐EGFRs achieved response. In conclusion, NRAS mutations have a relevant incidence in patients with mCRC and showed an association with specific clinical and pathological features. NRAS mutations affect mCRC patients' prognosis and predict lack of response to anti‐EGFRs.  相似文献   
93.
One challenge in biology is signal transduction monitoring in a physiological context. Intravital imaging techniques are revolutionizing our understanding of tumor and host cell behaviors in the tumor environment. However, these deep tissue imaging techniques have not yet been adopted to investigate the second messenger calcium (Ca2+). In the present study, we established conditions that allow the in vivo detection of Ca2+ signaling in three-dimensional tumor masses in mouse models. By combining intravital imaging and a skinfold chamber technique, we determined the ability of photodynamic cancer therapy to induce an increase in intracellular Ca2+ concentrations and, consequently, an increase in cell death in a p53-dependent pathway.  相似文献   
94.
Chimeric antigen receptor (CAR)-expressing T cells are a promising therapeutic option for patients with cancer. We developed a new CAR directed against the disialoganglioside GD2, a surface molecule expressed in neuroblastoma and in other neuroectoderm-derived neoplasms. The anti-GD2 single-chain variable fragment (scFv) derived from a murine antibody of IgM class was linked, via a human CD8α hinge-transmembrane domain, to the signaling domains of the costimulatory molecules 4-1BB (CD137) and CD3-ζ. The receptor was expressed in T lymphocytes by retroviral transduction and anti-tumor activities were assessed by targeting GD2-positive neuroblastoma cells using in vitro cytotoxicity assays and a xenograft model. Transduced T cells expressed high levels of anti-GD2 CAR and exerted a robust and specific anti-tumor activity in 4- and 48-hour cultures with neuroblastoma cells. Cytotoxicity was associated with the release of pro-apoptotic molecules such as TRAIL and IFN-γ. These results were confirmed in a xenograft model, where anti-GD2 CAR T cells infiltrating tumors and persisting into blood circulation induced massive apoptosis of neuroblastoma cells and completely abrogated tumor growth. This anti-GD2 CAR represents a powerful new tool to redirect T cells against GD2. The preclinical results of this study warrant clinical testing of this approach in neuroblastoma and other GD2-positive malignancies.  相似文献   
95.
The 8q24 region is a gene desert, although chromosomal aberrations and somatic amplification involving this region, including translocations involving the protooncogene c-MYC, have been frequently reported in people with cancer. To investigate the role of variants in 8q24 region, the authors analyzed data from a prospective study (n = 10,372 participants who were followed for 11 years) in which a large number of health events (>1,500) occurred (1993-1998). They genotyped all subjects for 5 candidate single nucleotide polymorphisms (rs672888, rs1447295, rs9642880, rs16901979, and rs6983267) that were identified in previous genome-wide scans. Although significant associations with individual single nucleotide polymorphisms were small in magnitude, the authors observed higher increases in the risks of different types of cancer with specific haplotypes, particularly when subjects were homozygous for the haplotype: for breast cancer and homozygotes for haplotype CAGCT, hazard ratio = 3.40, 95% confidence interval: 1.24, 9.21; for prostate cancer and grouped rare haplotypes, hazard ratio = 7.43, 95% confidence interval: 3.00, 18.37; and for brain cancer and homozygotes for haplotype CGGCT, hazard ratio = 13.48, 95% confidence interval: 3.00, 59.53. Significant associations were also observed between haplotypes and deaths from cardiovascular diseases and cerebrovascular diseases; the most stable association was between homozygotes for haplotypes CGTCG and CAGCT and total deaths in men (hazard ratio = 3.5, 95% confidence interval: 1.8, 6.9, and hazard ratio = 2.8, 95% confidence interval: 1.3, 6.4, respectively). In conclusion, the authors have observed a strong pleiotropic effect of the 8q24 region in a large prospective study. This observation can shed light on the mechanisms underlying reported associations between 8q24 variants and disparate chronic diseases.  相似文献   
96.
97.
Erythropoietin: Novel Approaches to Neuroprotection in Human Brain Disease   总被引:9,自引:0,他引:9  
With the increased life expectancy in western industrialized countries, the incidence and prevalence of brain diseases dramatically increased. Stroke and a wide spectrum of neuropsychiatric illnesses such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, traumatic head injury, and schizophrenia all lead to severe disability. However, targeted effective therapies for treatment of these diseases are lacking. Even more frustrating is the fact that we do not yet clearly understand the basic mechanisms underlying the disease processes in these conditions. We propose a hypothesis of loss of neuronal function via a final common deleterious pathway in this clinically very heterogeneous disease group. This review presents a novel neuroprotective concept for treatment of brain disease: Erythropoietin (EPO). EPO is a natural body-own-protein hormone that has been used for treatment of anemia for more than a decade. The neuroprotective approach using EPO in brain disease represents a totally new frontier. The “Göttingen EPO-stroke trial” represents the first effective use in man of a neuroprotective therapy in an acute brain disease while the experimental EPO therapy to combat cognitive decline in patients with schizophrenia will be introduced as an example of a neuroprotective strategy for a chronic brain disease.  相似文献   
98.
Ghrelin modulates somatotroph, lactotroph, corticotroph, and insulin secretion and glucose metabolism. To clarify the influence of gender and age on the endocrine actions of ghrelin in humans, we studied the effects of ghrelin (1.0 micro g/kg iv) or placebo on GH, prolactin (PRL), ACTH, cortisol, insulin, glucagon, and glucose levels in 18 young subjects (YS) and 16 elderly subjects (ES) of both genders. The GH response to GHRH (1.0 micro g/kg iv) was also studied. The GH response to ghrelin in YS was higher (P < 0.01) than in ES and both higher (P < 0.01) than to GHRH, without gender-related differences. In YS ghrelin also induced: 1) gender-independent increase (P < 0.01) in PRL, ACTH, and cortisol levels; 2) gender-independent increase in glucose levels (P < 0.01); 3) decrease (P < 0.01) in insulin levels in male YS; and 4) no change in glucagon. In ES, ghrelin induced gender-independent PRL, ACTH, and cortisol responses (P < 0.01). In ES ghrelin elicited gender-independent transient decrease in insulin (P < 0.01) coupled with increase in glucose levels (P < 0.05). In conclusion, the GH-releasing effect of ghrelin is independent of gender but undergoes age-related decrease. The effect of ghrelin on lactotroph and corticotroph secretion is age and gender independent. In both ES and YS, ghrelin influences insulin secretion and glucose metabolism.  相似文献   
99.
Neuropeptides are common mediators of the nervous and the immune systems. We investigated whether two families of peptides, calcitonin (CT) and somatostatin, posses human monocyte chemotactic activity. CT-related peptides induce a significant chemotactic response, and the potency order is: salmon CT greater than human CT greater than CT much greater than carbo-CT; CT gene-related peptide is completely inactive. This rank potency order differs from that in other systems (e.g. bone and nervous system). The chemotactic response of monocytes obtained from patients chronically treated with either salmon CT or carbo-CT is impaired, thus suggesting a phenomenon of down-regulation of a common receptor on monocytes. While somatostatin-(1-14) is completely inactive on monocyte chemotaxis, the synthetic analog SMS 201995 is extremely potent. Also, in this case the prolonged treatment of patients with SMS 201995 leads to an impaired chemotactic response.  相似文献   
100.
The effects of two intensities of formalin on behaviour and β-Endorphin (β-EP) concentration in the brain and pituitary were studied in male and female rats. The animals were familiarized with the Hole-Board apparatus for 3 days, and then, after a subcutaneous injection of formalin (50 μl, 0.1 or 10%) or Sham-injection (Control) in the hindpaw, they were tested in the Hole-Board for 60 min. Licking, Flexing and Paw-Jerk of the injected limb were recorded. β-EP concentration was determined in the hypothalamus (HYP), the periaqueductal gray matter (PAG), the anterior pituitary (AP) and the neurointermediate lobe (NIL). Licking and Flexing durations were greater in females than males only with formalin 10%. Sex differences in β-EP concentration between the Control groups were found in all tissues except the HYP; β-EP levels were higher in females in the PAG and NIL, but greater in the AP in males. β-EP concentration increased in males in the HYP and NIL with formalin 10%; in females, a decrease was found in the HYP with formalin 0.1%. The present results suggest that: (a) there are differences between males and females in the responses to formalin pain, and the nature (pattern and duration) of the sex differences varies according to the pain intensity; (b) there are differences in β-EP concentration between the two sexes in control animals, and male and female rats also exhibit differences in the modifications of β-EP in response to formalin-induced pain.  相似文献   
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