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21.
African-born immigrant women, and particularly refugees and asylum seekers, are at risk for reproductive health disparities but inadequately use relevant gynecologic services. We sought to elucidate perspectives on gynecologic care in a population of Congolese and Somali immigrants. We conducted a secondary qualitative analysis of focus group data using a grounded theory approach and the Integrated Behavioral Model as our theoretical framework. Thirty one women participated in six focus groups. Participant beliefs included the states of pregnancy and/or pain as triggers for care, preferences included having female providers and those with familiarity with female genital cutting. Barriers included stigma, lack of partner support, and lack of resources to access care. Experiential attitudes, normative beliefs, and environmental constraints significantly mediated care preferences for/barriers to gynecologic health service utilization in this population. Centering of patient perspectives to adapt delivery of gynecologic care to immigrants and refugees may improve utilization and reduce disparities.  相似文献   
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Bovine Viral Diarrhoea Virus (BVDV) is widely distributed in cattle industries and causes significant economic losses worldwide annually. A limiting factor in the development of subunit vaccines for BVDV is the need to elicit both antibody and T-cell-mediated immunity as well as addressing the toxicity of adjuvants. In this study, we have prepared novel silica vesicles (SV) as the new generation antigen carriers and adjuvants. With small particle size of 50 nm, thin wall (∼6 nm), large cavity (∼40 nm) and large entrance size (5.9 nm for SV-100 and 16 nm for SV-140), the SV showed high loading capacity (∼ 250 μg/mg) and controlled release of codon-optimised E2 (oE2) protein, a major immunogenic determinant of BVDV. The in vivo functionality of the system was validated in mice immunisation trials comparing oE2 plus Quil A (50 μg of oE2 plus 10 μg of Quil A, a conventional adjuvant) to the oE2/SV-140 (50 μg of oE2 adsorbed to 250 μg of SV-140) or oE2/SV-140 together with 10 μg of Quil A. Compared to the oE2 plus Quil A, which generated BVDV specific antibody responses at a titre of 104, the oE2/SV-140 group induced a 10 times higher antibody response. In addition, the cell-mediated response, which is essential to recognise and eliminate the invading pathogens, was also found to be higher [1954-2628 spot forming units (SFU)/million cells] in mice immunised with oE2/SV-140 in comparison to oE2 plus Quil A (512–1369 SFU/million cells). Our study has demonstrated that SV can be used as the next-generation nanocarriers and adjuvants for enhanced veterinary vaccine delivery.  相似文献   
25.
Biliary stenting is clinically effective in relieving both malignant and non-malignant obstructions. However, there are high failure rates associated with tumor ingrowth and epithelial overgrowth as well as internally from biofilm development and subsequent clogging. Within the last decade, the use of prophylactic drug eluting stents as a means to reduce stent failure has been investigated. In this review we provide an overview of the current research on drug eluting biliary stents. While there is limited human trial data regarding the clinical benefit of drug eluting biliary stents in preventing stent obstruction, recent research suggests promise regarding their safety and potential efficacy.  相似文献   
26.
S W Cook  N Mody  J Valle    R Hull 《Infection and immunity》1995,63(5):2082-2086
Proteus mirabilis bacteria are a common cause of hospital-acquired urinary tract infection. In a previous study, we described a P. mirabilis fimbrial protein, UCA, that adhered to human uroepithelial cells. Genes sufficient for expression of UCA adherence were cloned into Escherichia coli K-12. E. coli bacteria that contained the uca recombinant plasmid adhered to human uroepithelial cells. In addition, the ucaA gene encoding the structural component of UCA pili was subcloned, and its DNA sequence was determined. Amino acid sequence homology (30 to 50%) was found between mature UcaA protein and pilins from pathogenic bacteria representing several genera, including E. coli F17, G, and type 1C pilins, Haemophilus M43 pilin, and a Bordetella pilin.  相似文献   
27.
Virtually all cystic fibrosis (CF) patients become infected with Pseudomonas aeruginosa, and once the infection is established, the organism is rarely cleared. One of the P. aeruginosa virulence factors, exoenzyme S, has been shown to correlate with increased morbidity and mortality both in rat models of chronic pulmonary inflammation and in human CF patients. It has previously been shown that exoenzyme S is a potent stimulus for the proliferation of T cells in greater than 95% of adults, which could contribute to the pathogenesis of CF. The goal of this study was to determine the mechanism of T-cell stimulation by exoenzyme S in an effort to shed light on the immune response and contribute to understanding its role in P. aeruginosa pathogenesis. The current studies demonstrate that exoenzyme S stimulates naive T cells, since fetal blood lymphocytes proliferated and adult lymphocytes that expressed CD45RA proliferated. The percentage of T cells activated by exoenzyme S after a 4-h culture (as measured by CD69 surface expression) was intermediate in magnitude compared to levels induced by a panel of superantigens and mitogens. To determine the mechanism of activation, the requirement for accessory cells was investigated. The proliferative response to exoenzyme S was dependent on the presence of accessory cells but was not blocked by an anti-DR antibody. Exoenzyme S activated both CD4+ and CD8+ T cells, but CD4+ T cells were preferentially activated. The Vβ repertoire of donor T cells showed no preferential activation or preferential expansion after stimulation by exoenzyme S, suggesting that it is not a superantigen. Taken together, our data suggest that exoenzyme S is a T-cell mitogen but not a superantigen. Activation of a large percentage of T lymphocytes by exoenzyme S may produce a lymphocyte-mediated inflammatory response that should be considered in the pathogenesis of CF.  相似文献   
28.
Using a new antibody developed against the C-terminus of the cannabinoid receptor (CB1), the immunostaining in the hippocampus revealed additional axon terminals relative to the pattern reported previously with an N-terminus antibody. Due to a greater sensitivity of this antibody, a large proportion of boutons in the dendritic layers displaying symmetrical (GABAergic) synapses were also strongly immunoreactive for CB1 receptors, as were axon terminals of perisomatic inhibitory cells containing cholecystokinin. Asymmetrical (glutamatergic) synapses, however, were always negative for CB1. To investigate the effect of presynaptic CB1 receptor activation on hippocampal inhibition, we recorded inhibitory postsynaptic currents (IPSCs) from principal cells. Bath application of CB1 receptor agonists (WIN55,212-2 and CP55,940) suppressed IPSCs evoked by local electrical stimulation, which could be prevented or reversed by the CB1 receptor antagonist SR141716A. Action potential-driven IPSCs, evoked by pharmacological stimulation of a subset of interneurons, were also decreased by CB1 receptor activation. We also examined the effects of CB1 receptor agonists on Ca2+-independent miniature IPSCs (mIPSC). Both agonists were without significant effect on the frequency or amplitude of mIPSCs. Synchronous gamma oscillations induced by kainic acid in the CA3 region of hippocampal slices were reversibly reduced in amplitude by the CB1 receptor agonist CP 55,940, which is consistent with an action on IPSCs. We used CB1-/- knock-out mice to confirm the specificity of the antibody and of the agonist (WIN55,212-2) action. We conclude that activation of presynaptic CB1 receptors decreases Ca2+-dependent GABA release, and thereby reduces the power of hippocampal network oscillations.  相似文献   
29.
Many children with autism spectrum disorder (ASD) have notable difficulties in motor, speech and language domains. The connection between motor skills (oral-motor, manual-motor) and speech and language deficits reported in other developmental disorders raises important questions about a potential relationship between motor skills and speech-language deficits in ASD. To this end, we examined data from children with ASD (n?=?1781), 2–17 years of age, enrolled in the Autism Speaks—Autism Treatment Network (AS-ATN) registry who completed a multidisciplinary evaluation that included diagnostic, physical, cognitive and behavioral assessments as part of a routine standard of care protocol. After adjusting for age, non-verbal IQ, Attention Deficit Hyperactivity Disorder (ADHD) medication use, and muscle tone, separate multiple linear regression analyses revealed significant positive associations of fine motor skills (FM) with both expressive language (EL) and receptive language (RL) skills in an impaired FM subgroup; in contrast, the impaired gross motor (GM) subgroup showed no association with EL but a significant negative association with RL. Similar analyses between motor skills and interpersonal relationships across the sample found both GM skills and FM skills to be associated with social interactions. These results suggest potential differences in the contributions of fine versus gross motor skills to autistic profiles and may provide another lens with which to view communication differences across the autism spectrum for use in treatment interventions.  相似文献   
30.
Whether brain matter volume is correlated with cognitive functioning and higher intelligence is controversial. We explored this relationship by analysis of data collected on 193 healthy young and older adults through the “Leipzig Study for Mind–Body–Emotion Interactions” (LEMON) study. Our analysis involved four cognitive measures: fluid intelligence, crystallized intelligence, cognitive flexibility, and working memory. Brain subregion volumes were determined by magnetic resonance imaging. We normalized each subregion volume to the estimated total intracranial volume and conducted training simulations to compare the predictive power of normalized volumes of large regions of the brain (i.e., gray matter, cortical white matter, and cerebrospinal fluid), normalized subcortical volumes, and combined normalized volumes of large brain regions and normalized subcortical volumes. Statistical tests showed significant differences in the performance accuracy and feature importance of the subregion volumes in predicting cognitive skills for young and older adults. Random forest feature selection analysis showed that cortical white matter was the key feature in predicting fluid intelligence in both young and older adults. In young adults, crystallized intelligence was best predicted by caudate nucleus, thalamus, pallidum, and nucleus accumbens volumes, whereas putamen, amygdala, nucleus accumbens, and hippocampus volumes were selected for older adults. Cognitive flexibility was best predicted by the caudate, nucleus accumbens, and hippocampus in young adults and caudate and amygdala in older adults. Finally, working memory was best predicted by the putamen, pallidum, and nucleus accumbens in the younger group, whereas amygdala and hippocampus volumes were predictive in the older group. Thus, machine learning predictive models demonstrated an age‐dependent association between subcortical volumes and cognitive measures. These approaches may be useful in predicting the likelihood of age‐related cognitive decline and in testing of approaches for targeted improvement of cognitive functioning in older adults.  相似文献   
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