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91.
ObjectivesInstitutionalized older adults have a high prevalence of frailty and disability, which may make them more vulnerable to the negative consequences of coronavirus disease 2019 (COVID-19). We investigated the impact of COVID-19 on the level of frailty, physical, and cognitive performance in nursing home residents.DesignNested case-control study.Setting and ParticipantsThe study included nursing home residents who were infected with COVID-19 (case group, n = 76), matched by age to a control group (n = 76).MethodsParticipants’ sociodemographic and medical data were collected, and they were also assessed for physical function (handgrip and walking speed), cognitive performance (Mini-Mental State Examination) and frailty (Frail-NH scale) before the first wave of the COVID-19 pandemic (October to December 2019, pre-COVID-19) and after (June to July 2020, post-COVID-19). COVID-19 symptoms and clinical course were recorded for the cases.ResultsBetween the pre- and post-COVID-19 assessments, we found a 19% greater deterioration in handgrip, a 22% greater decrease in walking speed, and a 21% greater increase in Frail-NH scores in cases compared with controls. In both cases and controls, on the other hand, there was a significant 10% decrease in Mini-Mental State Examination scores over the study period. Multivariable logistic regression showed that COVID-19 survivors had a 4-fold increased chance of developing frailty compared with controls (odds ratio 4.95, 95% confidence interval 1.13–21.6, P = .03), but not cognitive decline.Conclusions and ImplicationsCOVID-19 can accelerate the aging process of institutionalized older adults in terms of physical performance and frailty by around 20%. However, we found similar levels of decline in cognitive performance in both cases and controls, likely because of the burden of social isolation and containment measures on neuropsychological health.  相似文献   
92.
Whether gestational immunization of HIV-infected mothers with the 23-valent pneumococcal polysaccharide vaccine (PPV) confers maternal and infant early life, passive protection is not known. We evaluated safety, immunogenicity and placental transfer of antibodies in 44 HIV-infected women. Pneumococcal IgG antibodies against serotypes 1, 3, 5, 6B, 9V, and 14 were measured in mothers (pre-vaccination and at delivery), and infants (at birth, 1, 2, 3, and 6 months). PPV was safe and immunogenic in mothers. Newborns received 46–72% of maternal antibody titers. Overall, infants had antibody levels lower than protective by 2 months of age. Alternative pneumococcal vaccination of HIV-infected pregnant women should be explored with the aim of prolonging passive protection in their infants.  相似文献   
93.
Summary

Normal rat serum shows antibacterial activity because of the presence of endogenous substances. The aim of this research was to study some aspects of the interaction between this biological fluid and some antibiotics, in order to demonstrate possible synergistic activity. Serum is able to lower the minimum inhibitory concentration of gentamicin and ofloxacin against some Gram-negative microorganisms. This can be explained by the presence of lysozyme, antibodies, β-lysin and other complementary factors that are able to cooperate with these antibiotics.  相似文献   
94.
Our objective was to evaluate the in vitro functional profile of T cells from uninfected neonates born from HIV-1-infected pregnant women who controlled (G1) or not (G2) the virus replication. We demonstrated that the lymphoproliferation of T cell to polyclonal activators was higher in the G2 as compared with G1. Nevertheless, no detectable proliferative response was observed in response to HIV-1 antigens in both neonate groups. Cytokine dosage in the supernatants of these polyclonally activated T cell cultures demonstrated that, while IL-10 was the dominant cytokine produced in G1, Th17-related cytokines were significantly higher in G2 neonates. The higher Th17 phenotype tendency in G2 was related to high production of IL-23 by lipopolysaccharide-activated monocyte-derived dendritic cells from these neonates. Our results demonstrated immunological disorders in uninfected neonates born from viremic HIV-1-infected mothers that can help to explain why some of these children have elevated risk of clinical morbidity and mortality due to pathological hypersensitivity.  相似文献   
95.
96.

Background:

Dislocation is one of the most common complications of total hip arthroplasty with a reported dislocation rate of 3.2%. Despite increased experience with hip replacement, the overall rate has not yet changed. The aim of this paper is to review the most recent literature published on this topic and indexed in Medline, in order to clarify the main risk factors, and to standardize a treatment protocol of such an important complication of prosthetic surgery.

Materials and Methods:

Medline database was searched using key words: “hip dislocation”, “hip instability” from 1980-2007. Studies were eligible for review and included if they met the following criteria: (1) publication in English, (2) clinical trials (3) review papers.

Results:

The risk of first-time dislocation as a function of time after the surgery is not well understood. Most, but not all, series have demonstrated that the risk of dislocation is highest during the first few months after hip arthroplasty; however, first-time late dislocation can also occur many years after the procedure. Several risk factors were described, including the surgical approach, the diameter of the head, impingement, component malposition, insufficient abductor musculature. In addition, there are also many treatment options, such as long-term bracing after closed reduction, component reorientation, capsulorraphy, trochanteric advancement, increasing offset, exchange of the modular head and the polyethylene liner, insertion of constrained liner.

Conclusion:

Preventing hip dislocation is obviously the best strategy. Surgeons must take into account patient and surgical risk factors. For patients at high risk for dislocation the surgeon should accurately restore leg length and femoral offset; the use of larger femoral heads, posterior transosseous repair of the capsulotendinous envelope if posterior approach is chosen or the use of a lateral approach should be considered. Proper patient education and postoperative care are very important.  相似文献   
97.
BACKGROUND: Involvement of the oral mucosa can occur in lepromatous leprosy; however, lesions in the oral mucosa of paucibacillary patients have not been previously observed. OBJECTIVE: The objective of this study is to determine whether clinical and subclinical lesions exist in oral mucosa in nontreated paucibacillary leprosy patients, using clinical and histopathological examination. MATERIALS AND METHODS: A clinical and histopathological study involving 30 untreated paucibacillary leprosy patients was conducted. All patients underwent biopsies of the buccal mucosa, soft palate, and tongue. When acid-fast bacilli in association with inflammatory infiltrate, granulomatous or not, were encountered, it was considered "specific" involvement of the oral mucosa; and "nonspecific" involvement when the bacilli were not encountered. RESULTS: Eight nonspecific chronic inflammatory reactions and 1 granulomatous inflammatory process without acid-fast bacilli were detected. CONCLUSIONS: Paucibacillary leprosy patients do not exhibit specific, clinical or subclinical, involvement in the oral mucosa; nonspecific alterations occur even in the absence of signs and symptoms.  相似文献   
98.
99.

Objective

This study investigated the effect of passive ultrasonic irrigation (PUI) on diffusion of hydroxyl ions through radicular dentine.

Materials and methods

After chemomechanical preparation of root canals in 60 human teeth, the cementoenamel junction and the apical 3 mm of each root were covered with fast-setting adhesive. Four final irrigation protocols were applied (n?=?10): group (G)1: irrigation with EDTA?+?NaOCl; G2: EDTA?+?PUI?+?NaOCl; G3: EDTA+(NaOCl?+?PUI); G4: (EDTA?+?PUI)?+?(NaOCl?+?PUI). Ten teeth irrigated with distilled water followed by PUI (G5) served as the negative control. After drying, the canals were filled with calcium hydroxide paste (CH), sealed and kept in individual vials containing 10 mL of distilled water with known pH values. At 7, 14, and 21 days, the pH of the water in the vials was measured. The pH values in various groups were analyzed with two-way ANOVA (irrigation protocol and time period as factors) and Holm-Sidak multiple comparison test (α?=?0.05).

Results

Changes in pH was not significantly different among groups (P?=?0.651) but was significant different among different time periods (P?<?0.0001). For all groups, ion diffusion was higher at 14 and 21 days than at 7 days.

Conclusions

PUI has no effect on diffusion of hydroxyl ions through radicular dentine. When CH is used as temporary filling material, a waiting period of at least 14 days is required to create an alkaline environment within the radicular dentine.

Clinical relevance

The use of PUI during final irrigation phase does not improve the action of CH when it is used as temporary filling material.
  相似文献   
100.
BackgroundDelayed surgery (ie, >48 hours from arrival in hospital) and pre-fracture disability are thought to be long-term risk factors for mortality in patients with hip fracture (HF). However, the combined effect on mortality of these two conditions has not been satisfactorily assessed in previous studies.ObjectiveTo assess the combined effect of pre-fracture disability and delayed surgery on 12-month mortality in a population of elderly patients after HF surgical treatment.DesignRetrospective cohort study with 12-month follow-up.SettingAn orthogeriatric unit (OGU) in a university hospital in Italy.MethodsAll patients (n = 390) admitted to an OGU from March 2007 to December 2010 who underwent proximal HF surgery and who were not transferred to other hospitals were considered for the analyses. Pre-fracture disability was defined as having an impairment in more than one activity of daily living (ADL). The 12-month mortality was assessed by a Kaplan–Meyer analysis and by a Cox proportional hazards regression models adjusting for relevant potential confounders.ResultsAfter adjusting for potential confounders, patients with both delayed surgery and pre-fracture disability had a significantly higher 12-month mortality (hazard ratio [HR] = 5.80; 95% confidence interval [CI] = 2.11–15.92) than patients with neither delayed surgery nor disability (reference group). Patients with disability but not delayed surgery had a nearly 4-fold increased mortality risk (HR, 3.98; 95% CI 1.41–11.27) than patients in the reference group.ConclusionsPatients with both pre-fracture disability and delayed HF surgical treatment had a nearly six-fold increased 12-month mortality risk than did patients with neither disability nor delayed surgery.  相似文献   
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