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1.
Case reports of 151 patients above the age of 70 years, treated with colon diseases of surgical interest, have been compared to those of 220 patients treated with similar diagnoses, but in younger ages. The case reports were evaluated on the basis of the available literary data, and interpreted from the points of view of the geriatric pathology. It is concluded that a correct interpretation of surgical pathologies of the colon in the elderly cannot disregard the knowledge of the age-dependent involutive processes concerning particularly this part of the digestive tract, and also other organs and systems in global sense. Aging of the mucosa of colon, after all, represents a more or less expressed reduction of its barrier function against oncogenic factors and pathogenic microorganisms. The degenerative lesions involving continuously the micro- and macrocirculation of the splanchnic regions result in a more frequent occurrence of complications (ischemia, perforations). The instability of the bioimmunological equilibrium and the presence of accompanying diseases complicate further the clinical picture which displays usually a few symptoms even during the evolutive phases of the diseases. Once the diagnosis has been achieved, the therapeutic strategies should be modified individually without giving up the main principles, however, always considering the possible expectations as regards the quality of life of each patients for the remaining life.  相似文献   
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OBJECTIVE: HIV infections in children are characterized by high viral load and, in some perinatally infected newborns, delayed appearance of viral markers. Both phenomena may be related to different levels of immune activation affecting viral replication. This study was designed to investigate the relationship between immune activation and viral replication in pediatric HIV infection, and the role of pre-existent immune activation in facilitating HIV transmission to the fetus/newborn. DESIGN: Plasma levels of soluble L-selectin (s-LS), an immune activation marker, were determined in 100 infants with perinatally transmitted HIV infection, compared with 106 age-matched HIV-exposed uninfected controls. Included in the analysis were samples from 31 HIV-infected (10 PCR+ and 21 PCR-) and 35 uninfected newborns aged < 2 days. METHODS: To determine s-LS levels, a solid phase ELISA was performed on plasma samples of patients and controls. Results: s-LS levels in uninfected children were higher than those in normal adults. HIV-infected patients had more rapidly increasing values in the first 6 months of life compared with uninfected infants. Plasma s-LS levels correlated with HIV viral loads (r, 0.50). Among newborns in the first 2 days of life, s-LS levels were lowest in those with negative PCR tests, compared with PCR-positive or uninfected infants. CONCLUSIONS: These results suggest that higher immune activation in children contributes to higher viral loads, and that the level of pre-existent immune activation may have a role in determining which infants have detectable virus in peripheral blood at birth.  相似文献   
3.
Cytomegalovirus (CMV) infection is common among infants of HIV-infected mothers in resource-limited settings. We examined the prevalence and timing of infant CMV infection during the first year of life using IgG antibody and avidity among HIV-exposed infants in Malawi and correlated the results with the presence of detectable CMV DNA in the blood. The Breastfeeding, Antiretrovirals and Nutrition (BAN) study randomized 2,369 mothers and their infants to maternal antiretrovirals, infant nevirapine, or neither for 28 weeks of breastfeeding, followed by weaning. Stored plasma specimens were tested for CMV IgG and antibody avidity from a random subset of infants who had been previously tested with blood CMV PCR and had available specimens at birth and at 24 and 48 weeks of age. Ninety-four of 127 infants (74.0%) tested at 24 weeks of age had CMV IgG of low or intermediate avidity, signifying primary CMV infections. An additional 22 infants (17.3%) had IgG of high avidity; 19 of them had CMV DNA detected in their blood, indicating infant infections. Taken together, these results show that the estimated prevalence of CMV infection at 24 weeks was 88.9%. By 48 weeks of age, 81.3% of infants had anti-CMV IgG; most of them (70.9%) had IgG of high avidity. The CMV serology and avidity testing, combined with the PCR results, confirmed a high rate of primary CMV infection by 6 months of life among breastfeeding infants of HIV-infected mothers. The CMV PCR in blood detected most, but not all, infant CMV infections.  相似文献   
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Objectives

Little is known about the effects of commonly used lubricants on detection of biomarkers of semen exposure. We investigated the in vitro effect of Gynol®, K-Y Jelly®, Replens®, Astroglide®, Carbopol, and Silicorel on quantitative detection of prostate specific antigen (PSA).

Study Design

A predetermined concentration of each of the gels was added to serially diluted semen samples. Additionally, serial dilutions of each of the gels were added to three different semen dilutions (high, medium, or low). The resulting samples were tested for PSA on the Abbott ARCHITECT System.

Results

When using the Abbott ARCHITECT system, the only products that inhibited PSA detection were Gynol® and Replens®. The inhibition caused by Gynol® was dose-dependent, but that of Replens was dose-independent. K-Y Jelly®-spiked samples had higher PSA values than controls.

Conclusions

Caution is warranted when using the Abbott quantitative assay for PSA detection as a biomarker of semen exposure in settings where Gynol®, Replens® or K-Y Jelly® might also have been used. Neither Astroglide® nor Silicorel inhibited PSA detection. Additional studies evaluating other vaginal products, including microbicides, and their effects on other assays, are needed. In vivo studies will be especially important to optimize PSA detection from clinical samples.

Implications

Researchers should consider the potential for specific lubricants or any vaginal products to affect the particular assay used for semen biomarker detection. The Abbott ARCHITECT’s total PSA assay should not be used with the product Replens. Caution is warranted when using the assay in settings where Gynol or K-Y jelly may have been used.  相似文献   
7.

Objectives

There is currently no information on whether products evaluated in HIV microbicide trials affect the detection of the semen biomarkers prostate-specific antigen (PSA) or Y chromosome DNA.

Study Design

We tested (in vitro) dilutions of tenofovir (TFV), UC781 and the hydroxyethylcellulose (HEC) placebo gels using the Abacus ABAcard and the quantitative (Abbott Architect total PSA) assays for PSA and Y chromosome DNA by real-time polymerase chain reaction.

Results

TFV gel and the HEC placebo adversely affected PSA detection using the ABAcard but not the Abbott Architect total PSA assay. UC781 adversely affected both the ABAcard and Abbott Architect total PSA assays. While there were some quantitative changes in the magnitude of the signal, none of the products affected positivity of the Y chromosome assay.

Conclusions

The presence of TFV or HEC gels did not affect quantitative PSA or Y chromosome detection in vitro. Confirmation of these findings is recommended using specimens obtained following use of these gels in vivo.

Implications

Researchers should consider the potential for specific microbicides or any products to affect the particular assay used for semen biomarker detection. The ABAcard assay for PSA detection should not be used with TFV UC781, or HEC.  相似文献   
8.
Background: This narrative review presents the association between metabolic syndrome (MetS), along with its components, and cognition-related disorders, as well as the potential reversal role of diet against cognitive impairment by modulating MetS. Methods: An electronic research in Medline (Pubmed) and Scopus was conducted. Results: MetS and cognitive decline share common cardiometabolic pathways as MetS components can trigger cognitive impairment. On the other side, the risk factors for both MetS and cognitive impairment can be reduced by optimizing the nutritional intake. Clinical manifestations such as dyslipidemia, hypertension, diabetes and increased central body adiposity are nutrition-related risk factors present during the prodromal period before cognitive impairment. The Mediterranean dietary pattern stands among the most discussed predominantly plant-based diets in relation to cardiometabolic disorders that may prevent dementia, Alzheimer’s disease and other cognition-related disorders. In addition, accumulating evidence suggests that the consumption of specific dietary food groups as a part of the overall diet can improve cognitive outcomes, maybe due to their involvement in cardiometabolic paths. Conclusions: Early MetS detection may be helpful to prevent or delay cognitive decline. Moreover, this review highlights the importance of healthy nutritional habits to reverse such conditions and the urgency of early lifestyle interventions.  相似文献   
9.
Studies of HIV-1-infected humans indicate that the thymus can be infected by HIV-1. In some of these patients, there is a significant CD4(+) T cell decline and a faster disease progression. This phenomenon is more evident in pediatric patients who depend heavily on their thymus for generation of new T cells. We hypothesize that HIV-1 causes T cell regenerative failure within the thymus, which has a profound impact on disease progression. Building on our established human thymopoiesis model, we include dynamic interactions between different HIV-1 strains (R5 and X4) and thymocytes. Our results predict that thymic infection with different HIV-1 strains induces thymic dysfunction to varying degrees, contributing to differences in disease progression as observed in both HIV-1-infected children and adults. Thymic infection in children is more severe than in adults, particularly during X4 infection. This outcome is likely due to both a higher viral load and a more active thymus in pediatric patients. Our results also indicate that a viral strain switch from R5 to X4 induces further deterioration in thymopoiesis. We predict that both viral and host factors play key roles in controlling thymic infection, including strain virulence and health status of the thymus.  相似文献   
10.
BACKGROUND: Ghrelin is a novel peptide associated with energy balance, obesity, and perhaps gonadal function. The present study was designed in order: (i) to compare plasma ghrelin levels between women with PCOS, women who presented only with hyperandrogenaemia and healthy controls; and (ii) to investigate the relationship between circulating ghrelin and the heterogeneity of clinical and biochemical manifestations of PCOS. METHODS: Two hundred and fifty-nine women with PCOS, 25 women who had only hyperandrogenaemia and 46 controls, were studied. Women with PCOS were further divided, based on the presence of chronic anovulation, biochemical hyperandrogenaemia, clinical hyperandrogenism, and polycystic ovary morphology on ultrasound evaluation. In all women, the basal levels of gonadotrophins, androgens, 17-OH-progesterone, sex hormone-binding globulin, glucose, insulin and ghrelin were measured. RESULTS: Women with PCOS had lower ghrelin levels, compared to both women with hyperandrogenaemia and controls; women with hyperandrogenaemia had lower ghrelin levels, compared to controls, but not significantly so. While PCOS-associated hyperandrogenaemia was inversely related to ghrelin levels, anovulation and polycystic ovary morphology were associated with higher concentrations. Ghrelin levels were negatively correlated with 17-OH-progesterone levels. CONCLUSIONS: In PCOS, circulating ghrelin and androgens are inversely related and it is possible that this peptide is involved in steroidal synthesis and/or action. It is also likely that different clinical and biochemical manifestations of the syndrome are also associated with different ghrelin concentrations.  相似文献   
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