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971.
972.
OBJECTIVES: A population-based study was used to describe healthcare seeking behavior for menopausal symptoms and treatment among women 40-65 years old in the United States. METHODS: Participants were recruited into the Menopause Epidemiology Study from the KnowledgePanel(SM), which is selected by random digit dialing and probability sampling from the US population. From this source, 6201 women 40-65 years old were contacted and 4402 women participated. From the 3135 peri- and postmenopausal women, detailed information was obtained on menopausal symptoms, healthcare seeking, medication usage, and symptom relief from the medication. RESULTS: Many women (60%) reported seeking health care for their menopausal symptoms. More than half of these women sought health care in the past 12 months. Vasomotor symptoms were the most frequently reported menopause symptoms across all races/ethnicities, and the most common symptoms discussed with a health care professional. One-third of the women (34%) used only hormone therapies, 12% used complementary and/or alternative medicines, and 16% used both for treatment of menopausal symptoms. CONCLUSIONS: This study has shown that a large number of women consult healthcare providers for menopausal symptoms, indicating these symptoms are bothersome. Yet, in the United States, there is considerable variation in the symptomatology, healthcare seeking, and use of therapies for menopausal symptoms across cultures. To alleviate these symptoms women have tried alternative treatments as well as hormone therapies, yet many women did not get complete relief of specific symptoms.  相似文献   
973.
Anti-IgE treatment of eosinophil-associated gastrointestinal disorders   总被引:3,自引:1,他引:2  
BACKGROUND: Eosinophil-associated gastrointestinal disorders (EGIDs) are commonly associated with atopy and are being recognized with increasing frequency. Current therapy for EGIDs is inadequate. OBJECTIVE: We sought to determine the efficacy of anti-IgE therapy in EGIDs and investigate the role of IgE in disease pathogenesis. METHODS: Nine subjects with EGIDs received omalizumab every 2 weeks for 16 weeks while other therapy was held constant. Blood absolute eosinophil counts, tissue eosinophil counts, symptom scores, and free IgE levels were serially measured. Allergen skin testing and flow cytometry for basophil activation and FcepsilonRI were determined at baseline and at week 16. RESULTS: Omalizumab was associated with a decrease in absolute eosinophil count at both the week 16 (34%, P = .004) and combined weeks 12 to 16 (42%, P = .012) time points. Tissue eosinophils decreased in the duodenum (59%) and gastric antrum (69%) but did not reach statistical significance (P = .074 and .098, respectively). Esophageal eosinophil counts remained unchanged. Basophil and dendritic cell FcepsilonRI expression and free IgE levels were all significantly decreased (P < .005). Omalizumab increased the concentration of allergen required to trigger half-maximal basophil activation by 170-fold. Allergen skin test wheal and erythema responses decreased by 78% and 82%, respectively. Symptom scores were decreased at both the midstudy (63%) and end of study (70%) time points (P < .005 for both). CONCLUSION: These results demonstrate that IgE-mediated processes contribute to the generation of eosinophilic inflammation in EGIDs and suggest that anti-IgE therapy might be effective in these disorders. CLINICAL IMPLICATIONS: Anti-IgE might be a potential therapy for EGIDs.  相似文献   
974.
The American Academy of Allergy, Asthma & Immunology and the American College of Allergy, Asthma and Immunology Executive Committees formed the Omalizumab Joint Task Force with the purpose of reviewing the Genentech Xolair (omalizumab) clinical trials and postmarketing surveillance data on anaphylaxis and anaphylactoid reactions. Using the definition of anaphylaxis proposed at a 2005 multidisciplinary symposia, the Omalizumab Joint Task Force concluded that 35 patients had 41 episodes of anaphylaxis associated with Xolair (omalizumab) administration between June 1, 2003, and December 31, 2005. With 39,510 patients receiving Xolair (omalizumab) during the same period of time, this would correspond to an anaphylaxis-reporting rate of 0.09% of patients. Of those 36 events for which the time of reaction was known, 22 (61%) reactions occurred in the first 2 hours after one of the first 3 doses. Five (14%) of the events after the fourth or later doses occurred within 30 minutes. Considering the timing of these 36 events, an observation period of 2 hours for the first 3 injections and 30 minutes for subsequent injections would have captured 75% of the anaphylactic reactions. The OJTF report provides recommendations for physicians who prescribe Xolair (omalizumab) on (1) the suggested wait periods after administration and (2) patient education regarding anaphylaxis.  相似文献   
975.
Recent reports have noted a discernible increase in the number of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) infections in patients without traditional risk factors. In the United States, the most prominent CA-MRSA strain encodes Panton-Valentine leukocidin (PVL) cytotoxin genes, belongs to pulsed field gel electrophoresis type USA300 and multilocus sequence type 8, and carries staphylococcal cassette chromosome mec (SCCmec) type IV. At present, molecular characterization of MRSA strains, such as USA300, can be time-consuming and is often beyond the technical capability of many clinical laboratories, making routine identification difficult. We analyzed the chromosomal regions flanking the SCCmec element in 44 USA300 MRSA isolates and identified a signature "AT repeat" sequence within the conserved hypothetical gene SACOL0058 located 1.4 kb downstream of the 3' end of the J1-SCCmec chromosomal junction. Only USA300 isolates tested contained a sequence of > or =6 AT repeats in combination with PVL (e.g., related USA500 or Iberian strains had > or =6 AT repeats but were PVL negative). Using a locked nucleic acid primer specific for > or =6 AT repeats in combination with primers to detect PVL, we developed a multiplex PCR assay specific for the identification of USA300 strains. Multiplex results were 100% concordant with DNA sequencing, suggesting that the method has promise as a means of rapidly identifying USA300 isolates.  相似文献   
976.
It is rarely considered that age-related common vascular co-morbidities may affect therapeutic outcomes of antiangiogenic therapy in cancer. Indeed, the accepted model of human disease consists of 4- to 8-week-old (young) tumor-bearing, but otherwise healthy, experimental mice, yet human cancers are diagnosed and treated in later decades of life when atherosclerosis and vascular diseases are highly prevalent. Here we present evidence that tumor growth and angiogenesis are profoundly altered in mice affected by natural aging and with genetically induced atherosclerosis (in ApoE(-/-) mice). Thus, transplantable tumors (Lewis lung carcinoma and B16F1) grew at higher rates in young (4 to 8 weeks old) ApoE(+/+) and ApoE(-/-) nonatherosclerotic syngeneic recipients than in their old (12 to 18 months old) or atherosclerotic (old/ApoE(-/-)) counterparts. These age-related changes were paralleled by reduced tumor vascularity, lower expression of tumor endothelial marker 1, increased acute tumor hypoxia, depletion of circulating CD45(-)/VEGFR(+) cells, and impaired endothelial sprouting ex vivo. Exposure of tumor-bearing mice to metronomic therapy with cyclophosphamide exerted antimitotic effects on tumors in young hosts, but this effect was reduced in atherosclerotic mice. Collectively, our results suggest that vascular aging and disease may affect tumor progression, angiogenesis, and responses to therapy.  相似文献   
977.
TAR DNA-binding protein 43 (TDP-43) is a major pathological protein of sporadic and familial frontotemporal lobar degeneration with ubiquitin-positive, tau-negative inclusions (FTLD-U) with or without motor neuron disease (MND). Thus, TDP-43 defines a novel class of neurodegenerative diseases called TDP-43 proteinopathies. We performed ubiquitin and TDP-43 immunohistochemistry on 193 cases of familial and sporadic FTLD with or without MND. On selected cases, immunoelectron microscopy and biochemistry were performed. Clinically defined frontotemporal dementias (FTDs) included four groups: 1) familial FTD with mutations in progranulin (n = 36), valosin-containing protein (n = 5), charged multivesicular body protein 2B (n = 4), and linked to chromosome 9p (n = 7); 2) familial cases of FTD with unknown gene association (n = 29); 3) sporadic FTD (n = 72); and 4) familial and sporadic FTD with MND (n = 40). Our studies confirm that the spectrum of TDP-43 proteinopathies includes most cases of sporadic and familial FTLD-U with and without MND and expand this disease spectrum to include reported families with FTD linked to chromosome 9p but not FTD with charged multivesicular body protein 2B mutations. Thus, despite significant clinical, genetic, and neuropathological heterogeneity of FTLD-U, TDP-43 is a common pathological substrate underlying a large subset of these disorders, thereby implicating TDP-43 in novel and unifying mechanisms of FTLD pathogenesis.  相似文献   
978.
Bacterium-induced diarrhea results in 2 to 2.5 million deaths in the world each year. The mechanism needs to be further understood. Staphylococcus aureus infection has a close relation with diarrhea; its cell wall component peptidoglycan (PGN) has strong biological activity on immune cells and possibly plays a role in S. aureus-induced diarrhea. The present study showed that oral PGN-induced diarrhea in mice in a dose-dependent manner. Intestinal epithelial cells absorbed PGN via the intracellular pathway. Intestinal mast cells were activated after PGN gavage. Toll-like receptor (TLR)2 expression was detected in mast cells in the intestine as well as in the murine mast cell line p815 cells. Blocking TLR2 or nucleotide-binding oligomerization domain (NOD)1 with related antibodies or RNA interference abolished PGN-induced p815 cell activation. The mast cell mediator histamine and serotonin had synergistic effects in PGN-induced diarrhea. In summary, oral PGN can induce diarrhea in mice, and TLR2 and NOD1 mediate the PGN-induced mast cell activation that plays a critical role in diarrhea induction. Blockade of TLR2 or NOD1 or treating mice with a mast cell stabilizer can efficiently inhibit PGN-induced-diarrhea, providing potential therapeutic significance.  相似文献   
979.
West Nile virus (family Flaviviridae, genus Flavivirus, WNV) persistently infects many mosquito tissues, and it has been associated with cytopathological changes in midgut muscles and salivary glands. However, the effects of WNV infection on mosquito fitness (survival and reproduction) are not known. We conducted a life table study of individually housed female Culex tarsalis Coquillett. After an initial bloodmeal from a WNV-infected or uninfected chicken, mosquitoes were provided sucrose and offered weekly opportunities to feed on a hanging blood drop. WNV transmission status was determined by testing the remaining blood drop for virus after mosquito feeding. Dead mosquitoes and eggs were collected daily. Mosquito legs and bodies were tested for WNV, and eggs were counted and allowed to hatch. Two replicates of this experiment were performed, with a total of 62 mosquitoes that fed on a WNV-infected chicken (of which 21 became infected) and 43 mosquitoes that fed on an uninfected chicken. Fecundity of WNV-infected mosquitoes was significantly lower than that of uninfected mosquitoes, especially during the first oviposition. WNV infection was associated with smaller egg rafts, whereas increasing wing length and WNV titer in the legs had a positive effect on egg raft size. Additionally, infected mosquitoes had lower egg hatch rates than did uninfected mosquitoes. There were no significant differences in survival between infected and uninfected mosquitoes. Blood feeding rates were higher in infected mosquitoes than in uninfected mosquitoes. A small amount of virus (average, 378; range, 5-5000 plaque-forming units) was transmitted to the blood drops fed upon by infected mosquitoes. Although WNV infection negatively impacts mosquito reproduction, facets of mosquito biology that are critical to virus transmission success were either not affected (survival) or changed in such a way as to result in enhanced vectorial capacity (blood feeding).  相似文献   
980.
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