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21.
In the original version of this article, the title was incorrect. Please find the correct title given here. The publisher deeply regrets this error. The original article to which this Erratum refers was published in Human Mutation 22:179–180 Human Mutation(2003) 22(2) 179–180  相似文献   
22.
The left ventricular subendocardial and subepicardial layers of six perfused rabbit hearts were tested for enzymatic and non-enzymatic antioxidant defences and for lipid peroxidation. The subendocardium showed significantly lower catalase activity and contents of non-protein thiol compounds and vitamin E associated with a higher degree of lipid peroxidation. The activities of Cu,Zn- and Mn-superoxide dismutases, glutathione reductase, -glutamylcysteine synthetase and -glutamyl transpeptidase showed no significant transmural differences, and Se-independent glutathione peroxidase activity was not detectable in either layer. Comparable results were observed in another group of six unperfused rabbit hearts. In five H2O2-perfused rabbit hearts, lipid peroxidation was higher, and myocardial creatine phosphokinase activity lower, in the subendocarium than in the subepicardium. In this group, only the subendocardium had significantly higher lipid peroxidation levels than the control hearts. Thus, a lower antioxidant capacity and a greater oxidative stress are present in the rabbit subendocardium. These findings could provide insight into the problem of subendocardial vulnerability to free radical-mediated processes, such as occurs in ischaemia-reperfusion injury.  相似文献   
23.
INTRODUCTION: Blue rubber bleb nevus syndrome (BRBNS) is a rare congenital systemic angiodysplasia with multiple vascular malformations in the skin, gastrointestinal tract and, less often, in other internal organs and the brain. CASE REPORT: A 36-year-old man with past history of BRBNS was admitted to our hospital for progressive dyspnea and fatigue. Primary pulmonary hypertension (PPH) was diagnosed. He then developed acute abdominal pain and dyspnea, dying in a few hours due to sudden cardiac arrest. Postmortem examination demonstrated angiomatous lesions located in the skin, small bowel, heart, lungs, liver and thyroid. The lesions were slightly raised, soft and compressible and microscopically consisted of dilated vascular channels lined by a flattened endothelium. The vascular wall was formed by several layers of smooth muscle cells, intermixed with abundant aggregates of elastic lamellae and thin collagen fibers. Luminal thrombi were a frequent finding. In the small bowel, we identified the presence of an abnormally large artery directly opening into a thin-walled venous channel. The most striking finding in the lungs was the presence of thrombi of varying age in the lumen of segmental and elastic arteries, as well as muscular arteries and arterioles. Severe medial hypertrophy of muscular arteries and muscolarization of arterioles were also present. Intimal proliferative lesions and plexiform lesions were never observed. CONCLUSION: The pulmonary findings are consistent with recurrent thromboembolic events from shunts in the visceral lesions. To our knowledge, this is the first report of BRBNS with visceral arterovenous (AV) fistulae complicated by thromboembolic pulmonary hypertension (PH).  相似文献   
24.
The pol and gag gene fragments of small ruminant lentivirus field isolates collected in the last decade in Italy were amplified, sequenced, and analyzed. Phylogenetic analysis revealed that the majority of ovine isolates form a distinct cluster more similar to caprine lentivirus prototypes than to the visna virus prototype. These findings confirm and extend those reported by Leroux et al. (Arch. Virol., 142:1125-1137, 1997). Moreover, we observed that a variable region of Gag, included in the fragment analyzed, corresponded to one of the three major capsid antigen epitopes, which suggests that the antibody response to this epitope may be type specific. To test this hypothesis, two recombinant peptides, derived from the Icelandic prototype K1514 and this novel genotype, were expressed and used in an enzyme-linked immunosorbent assay to screen a panel of ovine and caprine sera collected from different geographical locations in Italy. Several sera reacted in a type-specific manner, indicating that in a diagnostic setting the combination of at least these two type-specific peptides is necessary to cover a wide range of infections. Additionally, these results support the hypothesis of cross-species transmission based on the phylogenetic analysis described above. This has implications for the control and eradication of small ruminant lentivirus infections.  相似文献   
25.
A questionnaire-based retrospective clinical and immunological survey was conducted in 73 males with a definite diagnosis of X-linked agammaglobulinemia based on BTK sequence analysis. Forty-four were sporadic and 29 familial cases. At December 2000, the patients' ages ranged from 2 to 33 years; mean age at diagnosis and mean duration of follow-up were 3.5 and 10 years respectively. After the mid-1980s all but 2 were on intravenous immunoglobulin (IVIG) substitution therapy, with residual IgG >500 mg/dl in 94% of the patients at the time of enrollment. Respiratory infections were the most frequent manifestation both prior to diagnosis and over follow-up. Chronic lung disease (CLD) was present in 24 patients, in 15 already at diagnosis and in 9 more by 2000. The cumulative risk to present at diagnosis with CLD increased from 0.17 to 0.40 and 0.78 when the diagnosis was made at the ages of 5, 10, and 15 years respectively. For the 9 patients who developed CLD during follow-up, the duration of follow-up, rather than age at diagnosis; previous administration of intramuscular immunoglobulin; and residual IgG levels had a significant effect on the development of CLD. Chronic sinusitis was present in 35 patients (48%), in 15 already at diagnosis and in 20 by 2000. Sistemic infections such as sepsis and meningitis/meningoencephalitis decreased over follow-up, probably due to optimal protection provided by high circulating IgG levels reached with IVIG.  相似文献   
26.
An rK39 immunochromatographic test and immunofluorescent-antibody test (IFAT) for serodiagnosis of canine leishmaniasis were evaluated. The two tests showed correlation for all but one of the sera obtained from 68 dogs confirmed as leishmaniasis cases and 40 dogs (22 healthy dogs and 18 dogs with other diseases) from areas where the disease is not endemic. Specificity was 100% for both tests, while sensitivity was 97% for the rapid test and 99% for IFAT.  相似文献   
27.
Among therapeutic approaches that have been investigated, targeting of receptors implicated in managing neuroinflammation has been described. One such family of receptors comprises the formyl peptide receptors (FPRs) whose ligands could play a role in host defense. The murine FPR gene family includes at least six members while in humans there are only three. The two most important members are the Fpr1 and Fpr2. Fpr1encodes murine FPR1, which is considered the murine orthologue of human FPR. Resveratrol, a non-flavonoid polyphenol rich in red wine and grapes, apart from its beneficial health effects and anti-inflammatory properties, has been reported to reduce neuroinflammation in different neurodegenerative disease models. Resveratrol anti-inflammatory responses involve the activation of the protein deacetylase sirtuin 1 (SIRT1) gene. In this work we have investigated in an LPS-based murine model of neuroinflammation the role of FPR1, examining not only if this receptor undergoes a reduction of its expression during neuroinflammation, but also whether treatment with resveratrol was able to modulate its expression leading to an amelioration of neuroinflammatory picture in a murine model of neuroinflammation. Results of this work showed that FPR1 together with SIRT1 resulted upregulated by resveratrol treatment and that this increase is associated with an amelioration of the neuroinflammatory picture, as demonstrated by the induction of IL-10 and IL1-RA expression and the downregulation of proinflammatory mediators, such as TNF-α and IL-1β. The expression and the modulation of FPR1 by resveratrol may be evaluated in order to propose a novel anti-inflammatory and pro-resolving therapeutic approach for the reduction of the detrimental effects associated with neuro-inflammation based neurodegenerative diseases and also as a promising strategy to promote human health by a diet rich in antioxidative bioactive compounds.  相似文献   
28.
BackgroundTo diagnose periprosthetic joint infection (PJI) preoperatively, ultrasound-guided joint aspiration (US-JA) may not be performed when effusion is minimal or absent. We aimed to report and investigate the diagnostic performance of ultrasound-guided periprosthetic biopsy (US-PB) of synovial tissue to obtain joint samples in patients without fluid around the implants.MethodsOne-hundred nine patients (55 men; mean age: 68 ± 13 years) with failed total hip arthroplasty (THA) who underwent revision surgery performed preoperative US-JA or US-PB to rule out PJI.ResultsSixty-nine of 109 patients had joint effusion and underwent US-JA, while the remaining 40 with dry joint required US-PB. Thirty-five of 109 patients (32.1%) had PJI, while 74/109 (67.9%) had aseptic THA failure. No immediate complications were observed in both groups. Technical success of US-PB was 100%, as the procedure was carried on as planned in all cases. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of US-JA were 52.2%, 97.8%, 92.3%, 80.3%, and 82.6%, while for US-PB, they were 41.7%, 100%, 100%, 80%, and 82.5%, respectively, with no significant difference (P = .779). Using the final diagnosis as reference standard, we observed a moderate agreement with both US-JA (k = 0.56) and US-PB (k = 0.50).ConclusionWe present a novel US-guided technique to biopsy periprosthetic synovial tissue of failed THA to rule out PJI. We found similar diagnostic performance as compared with traditional US-JA. This supports future larger studies on this procedure that might be applied in patients without joint effusion.  相似文献   
29.
In secondary mitral regurgitation, the concept that the mitral valve (MV) is an innocent bystander, has been challenged by many studies in the last decades. The MV is a living structure with intrinsic plasticity that reacts to changes in stretch or in mechanical stress activating biohumoral mechanisms that have, as purpose, the adaptation of the valve to the new environment. If the adaptation is balanced, the leaflets increase both surface and length and the chordae tendineae lengthen: the result is a valve with different characteristics, but able to avoid or to limit the regurgitation. However, if the adaptation is unbalanced, the leaflets and the chords do not change their size, but become stiffer and rigid, with moderate or severe regurgitation. These changes are mediated mainly by a cytokine, the transforming growth factor‐β (TGF‐β), which is able to promote the changes that the MV needs to adapt to a new hemodynamic environment. In general, mild TGF‐β activation facilitates leaflet growth, excessive TGF‐β activation, as after myocardial infarction, results in profibrotic changes in the leaflets, with increased thickness and stiffness. The MV is then a plastic organism, that reacts to the external stimuli, trying to maintain its physiologic integrity. This review has the goal to unveil the secret life of the MV, to understand which stimuli can trigger its plasticity, and to explain why the equation “large heart = moderate/severe mitral regurgitation” and “small heart = no/mild mitral regurgitation” does not work into the clinical practice.  相似文献   
30.
With hindsight, the main weakness behind the ineffective response to the coronavirus disease 2019 (COVID-19) pandemic in some countries has been the failure to understand, and take account of, the multilayered systemic interdependencies that spread the effects of the pandemic across social, technological, economic and health-care dimensions. For example, to respond to the COVID-19 pandemic, all people were required to rapidly adjust to social distancing and travel restrictions. Such a complex behavioural response entails adaptation to achieve a full recovery from the systemic shock. To capitalize on the positive effects of disruption to the status quo, much more complex socioeconomic modelling needs to be considered when designing and evaluating possible public health interventions that have major behavioural implications. We provide a simple example of how this reasoning may highlight generally unacknowledged connections and interdependencies and guide the construction of scenarios that can inform policy decisions to enhance the resilience of society and tackle existing societal challenges.  相似文献   
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