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81.

Objectives

To investigate the effect of cognitive support (an associative orienting instruction at encoding) on contextual memory in depressed patients.

Methods

Seventeen patients (age 20-40 years, 14 women) diagnosed with major depressive disorder (MDD) and 22 healthy controls matched for age, gender and education completed a recognition memory task for item (object) and context (location), with or without an incidental binding cue at encoding. In addition, participants completed the vocabulary subtest of the Wechsler Adult Intelligence Scale (WAIS III) and the Wisconsin Card Sorting Test (WCST). Salivary samples were collected at 7 AM, 4 PM and 10 PM on the day of testing for cortisol and DHEA level measurement.

Results

Depressed patients showed a deficit in contextual memory in the absence of a binding cue but did not differ from healthy controls in item memory or when a binding cue was present. Cortisol and cortisol/DHEA ratios were lower in depressed patients compared to healthy controls and correlated with memory deficits.

Conclusions

Contextual memory deficits in MDD patients can be reduced by providing cognitive support at encoding.  相似文献   
82.
The identification and characterization of cancer stem cells might lead to more effective control of neoplastic disease, by directing therapies to the most aggressive cells. For that reason, the identification of cancer stem cells (CSCs) in breast tumours is one of the priorities in breast cancer research, which has resulted in many studies attempting to identify their presence based on the expression of specific molecular markers. In this review, we describe the main molecular markers that have been identified as being able to recognise CSCs in breast carcinomas, the major molecular pathways that regulate CSCs and their association with the different molecular subtypes.  相似文献   
83.
This study explores experiential avoidance as a mediator in the relationship between coping (rational coping, avoidant coping and detached/ emotional coping) and psychopathology (depression, anxiety and stress). A battery of self-report questionnaires was used to assess coping, experiential avoidance and depression, anxiety and stress in 70 participants with a chronic pain from Portuguese primary health care units. Regression analyses were performed and showed preliminary evidence supporting the mediation role of experiential avoidance in a Portuguese sample with chronic pain. Results show that experiential avoidance partially or fully mediate the effects of rational coping and detached/emotional coping on depression and stress. Implications for clinical practice were discussed and suggest that psychopathology is not necessary direct product of coping and other processes, such as experiential avoidance, are likely involved.  相似文献   
84.
85.

Objective

To determine human papillomavirus (HPV) genotypes and the physical status of HPV-16 DNA among women from northern Portugal with cervical lesions.

Methods

The present retrospective study included samples of cervical exfoliated cells from 88 women (median age 42.0 ± 13.1 years) who attended the Gynecology Service at the Portuguese Institute of Oncology in Porto during 2010. After DNA extraction, HPV genotyping was performed by polymerase chain reaction (PCR) followed by restriction fragment length polymorphism analysis using the MY09/MY11 primers. The physical status of HPV-16 was determined by real-time PCR.

Results

Overall, 69.3% of the samples tested positive. The prevalence of HPV infection was 38.5% in normal samples, 57.7% in cervicitis samples, and 87.2% in all cervical lesions including invasive cancers. Sixteen genotypes were detected, the most prevalent ones being HPV-16 (42.9%), HPV-31 (12.2%), and HPV-58 (10.2%); HPV-18 was rare. The overall prevalence of HPV-16 integration was 31.6%. The physical status of HPV-16 did not differ significantly by histology.

Conclusion

The most frequent genotypes were HPV-16, -31, and -58. Integration of HPV-16 DNA seemed to be an early event in cervical carcinogenesis. Further studies are required to clarify the value of viral integration as a prognostic marker.  相似文献   
86.

Objective

To investigate the prevalence of vulvodynia in Portugal and factors associated with this condition.

Methods

In a cross-sectional study, an online survey was distributed by email and posted on a website and social networks. Women aged at least 18 years who were living in Portugal were eligible to complete the survey between June 1 and November 30, 2013. Participants had to have had symptoms for at least 6 months to be deemed to have vulvodynia.

Results

Overall, 1229 questionnaires were included in analyses. A total of 80 (6.5%) women had vulvodynia at the time of the survey, and 117 (9.5%) had had it previously; lifetime prevalence was 16.0%. Pregnancy and type of delivery were not associated with vulvodynia. Women who had ever taken oral contraceptives were significantly more likely to have ever had vulvodynia (P < 0.010). Candidiasis, genital herpes, urinary tract infections, depression, and premenstrual syndrome were associated with ever having had vulvodynia (P < 0.01). Pain syndromes were associated with ever having had vulvodynia, especially fibromyalgia and bladder pain syndrome (P < 0.001). Scoliosis and hysterectomy were also significantly associated (P < 0.01).

Conclusion

The prevalence of vulvodynia in Portugal is similar to that elsewhere. Three main groups of factors might lead to vulvodynia: local inflammatory factors, general pain susceptibility, and pelvic nerve interference.  相似文献   
87.
88.
Poly-N-acetyl-glucosamine (PNAG) is a staphylococcal surface polysaccharide influencing biofilm formation that is also under investigation for its vaccine potential. Antibodies that bind to PNAG with either low (<15%) or high (>90%) levels of acetate are superior at opsonic and protective activity compared with antibodies that bind to PNAG with only high levels (>70%) of acetate. PNAG is synthesized by four proteins encoded within the intercellular adhesin (ica) locus icaADBC. In Staphylococcus epidermidis, icaB encodes a deacetylase needed for the surface retention of PNAG and optimal biofilm formation. In this study, we confirmed that icaB plays a similar role in Staphylococcus aureus and found that an icaB mutant of S. aureus expressed significantly less surface-associated PNAG, was highly susceptible to antibody-independent opsonic killing that could not be enhanced with antibody raised against deacetylated PNAG (dPNAG), and had reduced survival capacity in a murine model of bacteremia. In contrast, an icaB-overexpressing strain produced primarily surface-associated PNAG, was more susceptible to opsonophagocytosis with antibody to dPNAG, and had increased survival in a murine bacteremia model. The highly acetylated secreted PNAG was more effective at blocking opsonic killing mediated by a human monoclonal antibody (mAb) to native PNAG than it was at blocking killing mediated by a human mAb to dPNAG, which by itself was a more effective opsonin. Retention of dPNAG on the surface of S. aureus is key to increased survival during bacteremia and also provides a molecular mechanism explaining the superior opsonic and protective activity of antibody to dPNAG.  相似文献   
89.
Long-term treatment of mouse cancer cells with interferon-alpha (IFN-alpha) converts parental B16 melanoma cells to B16alpha vaccine cells. Inoculation of syngeneic mice with B16alpha vaccine cells triggers immunity to the parental B16 tumor that is mediated by host macrophages, T cells, and natural killer (NK) cells. Lymph node cells from mice inoculated with irradiated B16alpha vaccine cells, but not with irradiated parental cells, proliferate when cultured in vitro, suggesting long-term in vivo activation of lymphoid cells. Long-term IFN-alpha treatment of B16alpha vaccine cells induced both interleukin-15 (IL-15) mRNA and IL-15 protein. The bulk of the induced IL-15 remained cell associated, either cytoplasmic or associated with the cell membrane. Immunofluorescence microscopy studies showed that the cell-associated IL-15 was broadly distributed throughout the cytoplasm. These observations suggest that long-term IFN-alpha treatment may induce primarily the truncated isoform of IL-15. Vaccination with irradiated B16alpha vaccine cells may promote tumor immunity by releasing high levels of cell-associated IL-15 when spontaneously lysed or directly killed by innate immune cells. The release of accumulated cell-associated IL-15 may then trigger a host T cell response to tumor antigens and cause host development of immunity to the B16 tumor cells.  相似文献   
90.
Several reports have identified P[6] specificities in humans and in animals in different countries of the world, but few sequence data are available in public databases. In this work we have characterized the VP4 strains bearing P[6] specificity and NSP4 genotypes among diarrheic young children and diarrheic and non-diarrheic neonates from three studies previously conducted in Belém, Northern region of Brazil. As the to VP8* fragment, we observed a close relationship to both human prototypes of lineage P[6]-Ia (bootstrap of 99%) and porcine sublineages Ib and Ic (89.2-98.1% aa similarity and mean of 95%). With regards to the NSP4, the samples clustered into genotypes A and B. Of note, of the 27 P[6] strains analyzed in the present study and classified as genotype B, 8 (29.6%) were more similar to porcine prototypes when VP8* and NSP4 genes are compared, and were recovered, one from a neonate and seven from diarrheic children. These preliminary findings reinforce that further investigations are needed to assess the relative frequencies of P[6] strains in our region, as well as to investigate the potential for interspecies transmission involving humans and animals, particularly pigs.  相似文献   
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