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91.
The objective of the study is to assess the effects of emphysema on peak oxygen uptake ( $ \dot{V}{\text{O}}_{{ 2 {\text{peak}}}} $ ) during a cardiopulmonary exercise test in patients with chronic obstructive pulmonary disease (COPD). We measured $ \dot{V}{\text{O}}_{{ 2 {\text{peak}}}} $ and oxygen pulse in 80 patients with stable COPD exercising maximally. Oxygen saturation was measured by pulse oximetry (SpO2), and the ventilatory response assessed by the ratio of tidal volume (V T) at peak to slow vital capacity (SVC) at baseline, and by the percent increase of peak V T over baseline. Computed tomography imaging (CT scan) served as the reference diagnostic standard for emphysema. Based on the panel-grading (PG) method, emphysema was rated absent or mild (PG ≤ 30, n = 54), or moderate to severe (PG > 30, n = 26). Multiple quantile regression was applied to estimate the effects of PG > 30 on $ \dot{V}{\text{O}}_{{ 2 {\text{peak}}}} $ . At peak exercise, the patients with PG > 30 had significantly lower $ \dot{V}{\text{O}}_{ 2} $ , oxygen pulse and SpO2, and featured a blunted ventilatory response with respect to those with PG ≤ 30 (p < 0.001). With multiple quantile regression, the effects of PG > 30 on $ \dot{V}{\text{O}}_{{ 2 {\text{Peak}}}} $ were only partially explained by the degree of lung hyperinflation, a substantial component being imputable to impairment of lung diffusing capacity. In conclusion, chronic obstructive pulmonary disease patients with moderate to severe emphysema feature significantly lower exercise tolerance than those with no or mild emphysema. Our findings underscore the need of tailoring therapeutic interventions for COPD to the predominant clinical phenotype to improve exercise capacity.  相似文献   
92.
93.
Objective: To evaluate the diagnostic accuracy of cervicovaginal fetal fibronectin (fFN) in predicting preterm delivery (PTD) in symptomatic and asymptomatic women with cervical length (CL)?≤?20?mm.

Methods: A retrospective cohort study on pregnant singleton women admitted for CL?≤?20?mm, with or without uterine contractions, between 22 and 34 weeks. For each group, symptomatic and asymptomatic, the following outcomes were evaluated: PTD before 37 and 34 weeks, delivery within 48?h, 7, 14 and 21 days after fibronectin sampling.

Results: 128 women admitted for CL?≤?20?mm were identified. Of these, 43 had uterine contractions, while 85 were asymptomatic. A positive fFN test was detected in 33% of symptomatic patients and it was significantly associated with PTD?p?Conclusions: In women with contractions and CL?≤?20?mm, fFN is an effective marker of PTD. Sensitivity and specificity rates for PTD within 7–14 days are higher than those reported in studies including women with CL?>?20?mm. In asymptomatic women, fFN appeared not as effective in predicting PTD.  相似文献   
94.
95.
Donkeys, an endangered species, have recently gained a new application with the use of their milk to feed humans with allergic processes. The Ragusana donkey breed from Sicily is used to produce milk for humans with allergic diseases. In order to evaluate the hygienic, nutritional and management measures on a farm of Ragusana donkeys, complete blood counts, extended biochemical profiles and serum protein electrophoresis, as part of metabolic profile test (MPT), were performed in Ragusana donkeys. Fifty-four donkeys were studied and grouped according to their age, (1) 29 females and a single stallion (n=30), (2) young females, 1 – 3 years old (n=10) and (3) young of both sexes under 1 year old (n=14). The RBC count, RDW value, Lymp, and Mono counts, and PDW values were statistically greater in donkeys under one year old than in adult donkeys, while the Seg Neu count was lower. The CPK, ALP, iPhos, and HCO3, values were statistically higher in the group of donkeys under 1 year of age than adult donkeys while Cl and LDH values were statistically lower in donkeys under 1 year than adult donkeys. Additionally, statistically significant increased values for CPK, ALP, Alb, Chol, iPhos, HCO3, and UIBC in young donkeys under 1 year when compared with young donkeys, 1 – 3 years were observed. A statistically significant decreased value for Urea and an increased value for Crea in young donkeys, 1 – 3 years old were found as compared to adults. The serum protein fractions recognised by electrophoresis were: albumin, alpha globulin (subdivided into alpha-1 and alpha-2-globulins), beta globulin, and gamma globulin. In the alpha-1-globulin region three small peaks were constantly noticed, and alpha-2-globulins were statistically different between the three groups being greater in young donkeys under 1 year of age. The results obtained were used both to establish reference ranges and a data bank for the farm of Ragusana donkeys for future needs in assessing the metabolic status and health of the animals.  相似文献   
96.
Immunization of the female reproductive tract is important for protection against sexually transmitted diseases and other pathogens of the reproductive tract. However, intravaginal immunization with soluble antigens generally does not induce high levels of secretory immunoglobulin A (IgA). We recently developed safe mucosal adjuvants by genetically detoxifying Escherichia coli heat-labile enterotoxin, a molecule with a strong mucosal adjuvant activity, and here we describe the use of the nontoxic mutant LTK63 to induce a response in the mouse vagina against ovalbumin (Ova). We compared intravaginal and intranasal routes of immunization for induction of systemic and vaginal responses against LTK63 and Ova. We found that LTK63 is a potent mucosal immunogen when given by either the intravaginal or intranasal route. It induces a strong systemic antibody response and IgG and long-lasting IgA in the vagina. The appearance of vaginal IgA is delayed in the intranasally immunized mice, but the levels of vaginal anti-LTK63 IgA after repeated immunizations are higher in the intranasally immunized mice than in the intravaginally immunized mice. LTK63 also acts as a mucosal adjuvant, inducing a serum response against Ova, when given by both the intravaginal and intranasal routes. However, vaginal IgA against Ova is stimulated more efficiently when LTK63 and antigen are given intranasally. In conclusion, our results demonstrate that LTK63 can be used as a mucosal adjuvant to induce antigen-specific antibodies in vaginal secretions and show that the intranasal route of immunization is the most effective for this purpose.  相似文献   
97.

Background

Automated interpretations systems for anti-nuclear antibody (ANA), anti-double stranded DNA antibody (dsDNAab), and anti-neutrophil cytoplasmic antibody (ANCA) assessment by indirect immunofluorescence (IIF) have been recently introduced. The aim of this study was to compare the diagnostic performance of the automated IIF reading system AKLIDES with both traditional visual interpretation of IIF by laboratory experts and confirmatory tests.

Methods

Visual and automated autoantibody interpretations of IIF findings using AKLIDES pattern recognition algorithms were performed for ANA on HEp-2 cells (n = 182), dsDNAab on Crithidia luciliae (n = 44) and ANCA on human neutrophils (n = 46). All serum samples tested by IIF for ANCA and dsDNAab were also assessed with the corresponding enzyme-linked immunosorbent assays (ELISAs). Out of the 182 sera tested for ANA by IIF, 116 were also assessed for antibodies to extractable nuclear antigens (ENA) by ELISA and dot immunoassay (DIA).

Results

ANA testing showed an excellent agreement between visual and AKLIDES reading (98.9%). The overall agreement of dsDNAab testing on C. luciliae substrate slides was 91.0%, whereas ANCA showed a concordance of 89.1%. There was a remarkable agreement of AKLIDES findings for dsDNAab with confirmatory tests.

Conclusion

Visual and automated interpretations of IIF findings for ANA, ANCA, and dsDNAab demonstrated a good agreement when assessing patients with suspected autoimmune diseases. Automated interpretation systems such AKLIDES may improve laboratory efficiency and support standardization of IIF in clinical laboratories.  相似文献   
98.
Hormone replacement therapy (HRT) in young postmenopausal women is a safe and effective tool to counteract climacteric symptoms and to prevent long-term degenerative diseases, such as osteoporotic fractures, cardiovascular disease, diabetes mellitus and possibly cognitive impairment. The different types of HRT offer to many extent comparable efficacies on symptoms control; however, the expert selection of specific compounds, doses or routes of administration can provide significant clinical advantages. This paper reviews the role of the non-oral route of administration of sex steroids in the clinical management of postmenopausal women. Non-orally administered estrogens, minimizing the hepatic induction of clotting factors and others proteins associated with the first-pass effect, are associated with potential advantages on the cardiovascular system. In particular, the risk of developing deep vein thrombosis or pulmonary thromboembolism is negligible in comparison to that associated with oral estrogens. In addition, recent indications suggest potential advantages for blood pressure control with non-oral estrogens. To the same extent, a growing literature suggests that the progestins used in association with estrogens may not be equivalent. Recent evidence indeed shows that natural progesterone displays a favorable action on the vessels and on the brain, while this might not be true for some synthetic progestins. Compelling indications also exist that differences might also be present for the risk of developing breast cancer, with recent trials indicating that the association of natural progesterone with estrogens confers less or even no risk of breast cancer as opposed to the use of other synthetic progestins. In conclusion, while all types of hormone replacement therapies are safe and effective and confer significant benefits in the long-term when initiated in young postmenopausal women, in specific clinical settings the choice of the transdermal route of administration of estrogens and the use of natural progesterone might offer significant benefits and added safety.  相似文献   
99.
Recently adipose tissue has become a research topic also for the searching for an alternative stem cells source to use in cell based therapies such as tissue engineer. In fact Adipose Stem Cells (ASCs) exhibit an important differentiation potential for several cell lineages such as chondrogenic, osteogenic, myogenic, adipogenic and endothelial cells. ASCs populations isolated using standard methodologies (i.e., based on their adherence ability) are very heterogeneous but very few studies have analysed this aspect. Consequently, several questions are still pending, as for example, on what regard the existence/ or not of distinct ASCs subpopulations. The present study is originally aimed at isolating selected ASCs subpopulations, and to analyse their behaviour towards the heterogeneous population regarding the expression of stem cell markers and also regarding their osteogenic and chondrogenic differentiation potential. Human Adipose derived Stem Cells (hASCs) subpopulations were isolated using immunomagnetic beads coated with several different antibodies (CD29, CD44, CD49d, CD73, CD90, CD 105, Stro-1 and p75) and were characterized by Real Time RT-PCR in order to assess the expression of mesenchymal stem cells markers (CD44, CD73, Stro-1, CD105 and CD90) as well as known markers of the chondrogenic (Sox 9, Collagen II) and osteogenic lineage (Osteopontin, Osteocalcin). The obtained results underline the complexity of the ASCs population demonstrating that it is composed of several subpopulations, which express different levels of ASCs markers and exhibit distinctive differentiation potentials. Furthermore, the results obtained clearly evidence of the advantages of using selected populations in cell-based therapies, such as bone and cartilage regenerative medicine approaches.  相似文献   
100.
ObjectivesTo compare fosfomycin susceptibility testing with the commercial agar dilution (AD) test, AD Fosfomycin (Liofilchem, Roseto degli Abruzzi, Italy) and the reference AD method, using a collection of multidrug-resistant (MDR) Enterobacterales and Pseudomonas aeruginosa clinical isolates.MethodsThe collection included 119 carbapenemase-producing Enterobacterales, 53 Enterobacterales producing acquired AmpC-type and/or extended-spectrum β-lactamases and 38 carbapenemase-producing P. aeruginosa, including representatives of different high-risk clones. AD Fosfomycin and AD reference method (ISO 20776-1:2019) were performed starting from the same microbial suspension. Results were interpreted according to EUCAST clinical breakpoints (10.0). Essential agreement (EA), category agreement (CA) and error rates were calculated as described by the International Organization for Standardization.ResultsOf 172 Enterobacterales, 143 (83.1%, including 92.9% (52 of 56) of the NDM-producers and 84.2% (48 of 57) of the KPC-producers) were susceptible to fosfomycin using reference AD. A CA of 91.9% (158 of 172; 95% CI 87.1%–95.3%) and an EA of 92.5% (136 of 147; 95% CI 87.4%–96.0%), respectively, were calculated for the commercial AD Fosfomycin test, with 9.8% (14 of 143) of major errors and no very major errors (0 of 29). Overall, 86.8% (33 of 38) of P. aeruginosa showed a fosfomycin MIC ≤128 mg/L using reference AD. An EA of 84.8% (95% CI 66.3%–92.0%) was calculated for the commercial AD Fosfomycin test, with a CA of 100% (95% CI 93.6%–100%) when considering a tentative breakpoint at 128 mg/L.ConclusionsAD Fosfomycin showed an overall good concordance compared with reference AD.  相似文献   
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