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81.
This study characterizes methicillin-susceptible Staphylococcus aureus (MSSA) and methicillin-resistant S. aureus (MRSA) isolates recovered from nasal cultures of noninstitutionalized individuals in the United States obtained in 2001 to 2004 as part of the National Health and Nutrition Examination Survey. Every tenth MSSA isolate and all MRSA isolates were typed by pulsed-field gel electrophoresis (PFGE), screened for multiple toxin genes, and tested for susceptibility to 14 antimicrobial agents. USA200, USA600, and USA900 were the predominant PFGE types among MSSA isolates in both the 2001 to 2002 and the 2003 to 2004 time periods, although they accounted for only 51.3% of 316 MSSA isolates typed in 2001 and 2002 and only 43.4% of 237 MSSA isolates typed in 2003 and 2004. In contrast, USA100, USA800, and USA700 accounted for 80.0% of the 75 MRSA isolates typed in 2001 and 2002, while USA100, USA800, and USA300 accounted for 78.4% of 134 MRSA isolates typed in 2003 and 2004. The proportion of MRSA isolates that were USA300 increased significantly from the first to the second time period (P = 0.03). Most USA200 isolates (both MSSA and MRSA) carried the gene for toxic shock syndrome toxin; however, carriage of the genes encoding Panton-Valentine leukocidin, while common among MRSA of PFGE type USA300, was rare among MSSA USA300 in both time periods. Most MSSA isolates remained susceptible to all antimicrobial agents except erythromycin (79.1 and 76.0% susceptibilities in the 2001 to 2002 and the 2003 to 2004 periods, respectively). In contrast, the proportions of MRSA isolates that were susceptible to chloramphenicol, clindamycin, and erythromycin were lower in 2003 and 2004 than in 2001 and 2002, although none of these differences was statistically significant.  相似文献   
82.
OBJECTIVE: To investigate immunological changes during CD4-guided therapy interruption in HIV(+) patients who suspended HAART. PATIENTS: Seventeen patients aged > 18 years, who had received HAART for at least 12 months, and had a pre-interruption CD4+ cell count > 500 cells/microl, interrupted treatment. Median nadir CD4(+) cell count was 288 cells/microl. HIV plasma viral load at discontinuation was < 50 or > 50 copies/ml. Criteria for restarting treatment were: a CD4(+) T-lymphocyte count < 350 cells/microl on two separate occasions, a clinical manifestation of AIDS, and the patient's desire to resume HAART. Eleven patients were still off therapy after 12 months (group A); according to the first criterion, six patients restarted therapy within 12 months (group B). METHODS: Haematological, viro-immunological, cytofluorimetic and molecular assays were performed at baseline and every 2 months following standard methods. Statistical analysis was performed under Stata 7.0. RESULTS: In the first 2 months of treatment interruption, a significant increase in viral load and CD8(+) lymphocyte activation occurred. Then such parameters decreased and remained stable. In all patients, a decrease in CD4(+) lymphocytes took place as well, that affected in a similar manner naive, central memory, effector memory and terminally differentiated cells. Group B always presented lower amounts of CD4(+) effector memory lymphocytes. The expression of CD127 was always higher in group A. CONCLUSIONS: The loss of CD4(+) lymphocytes upon viral rebound is equal among naive and memory subsets. Patients with higher expression of CD127, who are likely to exert a better capacity to utilize endogenous interleukin-7 by T cells, could remain off therapy for longer periods.  相似文献   
83.
Psoriatic arthritis (PsA) is an inflammatory arthropathy associated with skin and/or nail psoriasis. TNF-α, in addition to its pro-inflammatory role, is an essential cytokine for the host's defense, and its depletion by treatment may facilitate the risk of viral infections or their reactivation. The aim of this study was to evaluate the efficacy and safety of TNF-α blockers in PsA patients with concurrent hepatitis C virus (HCV) infection. This is a multicenter study carried out in four Italian centers specialized in the diagnosis and treatment of PsA. At baseline and after 6 (T6) and 12 months (T12) of therapy, data concerning PsA activity and liver tests were registered. A total of 15 PsA patients with concomitant HCV infection were included in the study. At baseline, 13 patients had low viral load, and liver enzyme tests were within the normal range. During the observation period, these values remained stable. On the other hand, at baseline, a high viral load with slightly increased values of AST and ALT was detected in one patient. At T6 and T12, these values decreased. The remaining patient, at baseline, had low viral load, but with slightly increased AST and ALT values that normalized during the observation period. This is the greatest sample size available in the literature on this topic. The data suggests that anti-TNF-α agents are effective and safe in PsA patients with concomitant HCV. We suggest that the use of anti-TNF-α agents, accompanied by close monitoring, could be a therapeutic option.  相似文献   
84.
An association between Graves' disease (GD) and chronic hepatitis C (C-HC) has been observed both in the presence and the absence of recombinant interferon-alpha (rIFN-alpha) treatment. rIFN-alpha-induced GD is characterized by suppressed thyroid-stimulating hormone levels; normal or elevated free triiodothyronine (FT3) and free thyroxine (FT4) values; the presence of thyroid peroxidase antibodies, antithyroglobulin antibodies, and thyroid receptor antibodies; and high iodine thyroid uptake. In contrast, GD developed during C-HC without rIFN-alpha is less clearly defined. In this study, we examined two groups of patients: group A, 28 patients with C-HC treated with rIFN-alpha who developed GD after 1 to 9 months, and group B, 10 patients with C-HC who developed GD without a previous rIFN-alpha treatment. At the time of GD, both groups started methimazole therapy; thyroid function was reevaluated after 3, 6, 9, and 12 months. Group A patients continued IFN. After 12 months, all patients of group A were euthyroid, and 21 of them (75%) had already stopped methimazole treatment, whereas all patients of group B were euthyroid and only 2 (20%) had stopped methimazole. In conclusion, the data show a better course of GD, with a more precocious and significantly higher number of recoveries in patients with rIFN-alpha-induced GD than in rIFN-alpha-unrelated disease. Further studies are needed to establish whether the two types of GD differ not only from a clinical point of view but also because of different underlying pathogenetic mechanisms.  相似文献   
85.

Introduction

Cancer survival is related not only to primary malignancy but also to concomitant nonmalignant diseases. The aim of this study was to investigate the prognostic capacity of four comorbidity indices [the Charlson comorbidity index (CCI), the Elixhauser method, the National Institute on Aging (NIA) and National Cancer Institute (NCI) comorbidity index, and the Adult Comorbidity Evaluation-27 (ACE-27)] for both cancer-related and all-cause mortality among colorectal cancer patients. A modified version of the CCI adapted for colorectal cancer patients was also built.

Methods

The study population comprised 468 cases of colorectal cancer diagnosed between 1 January 2000 and 31 December 2010 at a community hospital. Data were prospectively collected and abstracted from patients’ clinical records. Kaplan-Meier method and multivariate logistic regression models were performed for survival and risk of death analysis.

Results

Only moderate or severe renal disease [hazard ratio (HR) 2.71, 95 % confidence interval (CI) 1.11–6.63] and AIDS (HR 3.27, 95 % CI 1.23–8.68) were independently associated with cancer-specific mortality, with a population attributable risk of 5.18 and 4.36 %, respectively. For each index, the highest comorbidity burden was significantly associated with poorer overall survival (NIA/NCI: HR 2.14, 95 % CI 1.14–4.01; Elixhauser: HR 1.98, 95 % CI 1.09–1.42; ACE-27: HR 1.78, 95 % CI 1.07–1.23; CCI: HR 1.68, 95 % CI 1.05–1.42) and cancer-specific survival. The modified version of the CCI resulted in a higher predictive power compared with other indices studied (cancer-specific mortality HR?=?2.37, 95 % CI 1.37–4.08).

Conclusions

The comorbidity assessment tools provided better prognostic prevision of prospective outcome of colorectal cancer patients than single comorbid conditions.  相似文献   
86.
Myelodysplastic syndromes (MDS) are common in elderly patients. Recombinant human erythro-poietin (rHuEPO) has been widely used to treat anemia in lower risk MDS patients, but few data are known about rHuEPO treatment in the very elderly patient group. In order to investigate the role of rHuEPO treatment in terms of response, overall survival (OS), and toxicity in a very elderly MDS patient group, 93 MDS patients treated with rHuEPO when aged ≥80 years were selected among MDS cases enrolled in a retrospective multicenter study by the cooperative group Gruppo Romano Mielodisplasie (GROM) from Jan 2002 to Dec 2010. At baseline, median age was 82.7 (range 80–99.1) with a median hemoglobin (Hb) level of 9 g/dl (range 6–10.8). The initial dose of rHuEPO was standard (epoetin alpha 40,000 IU/week or epoetin beta 30,000 IU/week) in 59 (63.4 %) pa-tients or high in 34 (36.6 %) (epoetin alpha 80,000 IU/week) patients. We observed an erythroid response (ER) in 59 (63.4 %) patients. No thrombotic event was reported. Independent predictive factors for ER were low transfusion requirement before treatment (p?=?0.004), ferritin <200 ng/ml (p?=?0.017), Hb >8 g/dl (p?=?0.034), and a high-dose rHuEPO treatment (p?=?0.032). Median OS from rHuEPO start was 49.3 months (95 % CI 27.5–68.4) in responders versus 30.6 months (95 % CI 7.3–53.8) in resistant patients (p?=?0.185). In conclusion, rHuEPO treatment is safe and effective also in the very elderly MDS patients. However, further larger studies are warranted to evaluate if EPO treatment could be worthwhile in terms of quality of life and cost-efficacy in very old patients.  相似文献   
87.
There is worldwide growing awareness of alpha 1-antitrypsin deficiency (AATD), a major hereditary disorder in Caucasians. The gold standard for laboratory diagnosis of AATD is thin-layer isoelectrofocusing (IEF), which is labor intensive and should be performed in reference laboratories. The aim of this study was to find an easy, fast, and cheap method for detecting alpha1-antitrypsin S and Z variants, the most frequent variants associated with AATD. The novel method herein described is based on SexAI/Hpy99I RFLP. We studied samples from 90 subjects enrolled in the Italian National Registry for AATD, previously typed by isoelectrofocusing. We found a complete agreement among our results, IEF, and genotypes obtained by standard methods. We concluded that this novel method combines efficiency, ease, swiftness, and low cost.  相似文献   
88.

Background  

Osteoclasts (OCs) are involved in rheumatoid arthritis and in several pathologies associated with bone loss. Recent results support the concept that some medicinal plants and derived natural products are of great interest for developing therapeutic strategies against bone disorders, including rheumatoid arthritis and osteoporosis. In this study we determined whether extracts of Emblica officinalis fruits display activity of possible interest for the treatment of rheumatoid arthritis and osteoporosis by activating programmed cell death of human primary osteoclasts.  相似文献   
89.
90.
ABSTRACT Objective: The purpose of this study was to understand the processes and interactions that African American tobacco control organizations use to engage African American communities in tobacco control efforts. Design and Sample: The study used grounded theory methods to interpret participant's perspectives on tobacco control. The study sample consisted of African American tobacco control program directors from African American tobacco control organizations throughout the United States. Measures: Data collection involved 1 interview per participant using a semistructured interview at a location selected by the participant. Each interview lasted approximately 30–90 min. Results: The results showed that organizations used specific strategies to involve African Americans in tobacco control. The tobacco control organizations built community capacity using 3 processes: developing relationships and partnerships, raising awareness, and creating collective power. Conclusion: Contextual, cultural processes, and historical references used by African American tobacco control organizations provide insight into how to engage African American communities in tobacco control efforts and achieve tobacco‐related health parity. Public health professionals and nurses should be aware of these and other strategies that may increase the involvement of African American communities in tobacco control.  相似文献   
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