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A panel of chimpanzee-human somatic cell hybrids was characterized by dual Alu-PCR of the chimpanzee DNA in the hybrid and subsequent hybridization of the labeled PCR products to human and chimpanzee chromosomes. In addition to the identification of the intact chimpanzee chromosomes retained in each hybrid, chromosome fragments were identified that will be useful in regional mapping. This technique also revealed the presence of centric inversions.  相似文献   
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Increased urinary excretion of urinary trypsin inhibitor (UTI) has been reported in various inflammatory conditions and in Alzheimer's subjects, but its diagnostic potential remains to be elucidated. A reliable and specific enzyme-linked immunosorbent assay (ELISA) test for the determination of the UTI in human urine was developed. This assay was performed using 96-well microtiter plates. The plate surface is coated with an anti-UTI polyclonal antibody, the urine sample was added in a dilution range, and the detection was achieved using the enzyme-conjugated antibody. The assay was quantified by the build-up of colored product upon the addition of the substrate. Recoveries were 93%, and the intra- and inter-assay CVs were 4.25% and 21%, respectively. The ELISA showed parallelism of standard and urine samples and no significant interference by the biological matrix. The usefulness of the assay has been demonstrated by applying it to urine samples from Alzheimer's disease patients, and comparing with negative controls. UTI urinary levels are significantly increased in Alzheimer's subjects.  相似文献   
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BACKGROUND: Both CXC and CC chemokines play an important role in leukocyte recruitment. However, a systematic examination of their production by human airway epithelial cells (HAECs) has not been carried out. The objective of this study was to investigate whether Th1- and Th2-type cytokines regulate chemokine production in HAECs. METHODS: HAECs were grown from both nasal and bronchial tissue and subsequently stimulated with either Th1- or Th2-type cytokines. RESULTS: Constitutive mRNA expression for gro-alpha, IL-8 and RANTES was seen in both human nasal and human bronchial epithelial cells. IL-4 was the strongest stimulus for both gene expression and protein production of the chemokines RANTES, IL-8 and gro-alpha, while both IL-13 and IFN-gamma were weaker inducers of these chemokines, with the exception of gro-alpha (IL-13 was a strong stimulus for gro-alpha production). TNF-alpha synergized with IL-4, and to a lesser extent with IFN-gamma and IL-13, to release RANTES, IL-8 and gro-alpha. IL-4 and to a lesser extent IL-13 and IFN-gamma stimulated the production of MCP-3 and -4, eotaxin and eotaxin-2 immunoreactivities. However, no induction of the mRNAs encoding these chemokines was observed, suggesting that they may be released from a preformed pool within the HAECs. CONCLUSION: These findings suggest that when released into the airways, Th2- and to a lesser extent Th1-type cytokines may stimulate recruitment of eosinophils and neutrophils through the release of CC (RANTES, MCP-3 and -4, eotaxin and eotaxin-2) and CXC chemokines (gro-alpha and IL-8).  相似文献   
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Epidemiological and pathogenetic evidences suggest a strong association between vascular risk factors and sporadic Alzheimer's disease (sAD). In agreement with the vascular hypothesis of AD, the role of various candidate genes for atherosclerosis has been investigated, leading to conflicting results. In order to clarify the significance of angiotensin-converting enzyme (ACE) gene insertion (I)/deletion (D) polymorphism in a group of patients with sAD, we conducted a case-control study including 149 cases and 149 age and sex matched controls. All subjects were genotyped for ACE and Apolipoprotein E (APOE). There were no significant differences in ACE genotype or allele frequencies between cases and controls, even after stratification for APOE4 carrier status. Our data suggest that the ACE I/D polymorphism is not associated to genetic susceptibility in sAD patients.  相似文献   
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The inflammatory and remodelling processes that underlie asthma result from a highly complex interaction between various cell types. Apart from inflammatory cells, such as eosinophils, activated T cells, mast cells and macrophages, structural tissue cells such as epithelial cells, fibroblasts and smooth muscle cells can also play an important effector role through the release of a variety of mediators, cytokines and chemokines. This results in an acute inflammatory response that is characterized by vascular leakage, mucus hypersecretion, epithelial shedding and widespread airway narrowing. At the same time, through the release of mediators, cytokines, chemokines and growth factors, epithelial and mesenchymal cells cause persistence of the inflammatory infiltrate and induce structural changes in the airway wall, such as increased thickness of the basement membrane, increased collagen deposition, changes in bronchial microcirculation, and smooth muscle hypertrophy and hyperplasia. The end result of airway inflammation and remodelling is an increased thickness of the airway wall, leading to a reduced baseline airway calibre and exaggerated airway narrowing.  相似文献   
7.
Background: The restrictions taken to control the rapid spread of COVID-19 resulted in a sudden, unprecedented change in people’s lifestyle, leading to negative consequences on general health. This study aimed to estimate the impact of such changes on migraine severity during 2020 March–May lockdown. Methods: Patients affected by migraine with or without aura, diagnosed by expert physicians, completed a detailed interview comprehensive of: assessment of migraine characteristics; measure of physical activity (PA) levels; measure of the intake frequency of main Italian foods; the Insomnia Severity Index (ISI) questionnaire investigating sleep disorders. Results: We included 261 patients with a mean age of 44.5 ± 12.3 years. During social distancing, 72 patients (28%) reported a headache worsening, 86 (33%) an improvement, and 103 (39%) a stable headache frequency. A significant decrease of the PA levels during COVID-19 quarantine in the whole study sample was observed (median total metabolic equivalent task (METs) decreased from 1170 to 510; p < 0.001). Additionally, a significant difference was reported on median ISI scores (from 7 to 8; p < 0.001), which were increased in patients who presented a stable or worsening headache. Conclusions: Our study confirmed that the restrictions taken during the pandemic have affected the practice of PA levels and sleep quality in migraine. Hence, PA and sleep quality should be assessed to find strategies for an improvement in quality of life.  相似文献   
8.
Background: Vitamin D plays a pivotal role in calcium and phosphorus metabolism, also influencing bone tissue. Several studies have reported that vitamin D blood levels were significantly lower in people with obesity, probably due to its uptake by the adipose tissue. Clinical studies that investigated the changes of circulating levels of vitamin D following weight loss reported controversial data. A very low-calorie ketogenic diet is acknowledged as a reliable treatment to achieve a rapid weight loss. Therefore, we investigated the effect of weight loss, consequent to a very low-calorie ketogenic diet, on vitamin D blood concentrations. Methods: A cohort of 31 people with obesity underwent a very low-calorie ketogenic diet for 10–12 weeks. The serum concentrations of vitamin D, parathormone, calcium and phosphorous were measured before and after weight loss; they were compared to a control group of 20 non-obese, non-diabetic, age- and gender-matched persons. Results: Patients with obesity had a higher habitual intake of vitamin D than the control group (p < 0.05). However, the vitamin D blood levels of the obese group were significantly lower than those of the control group (p < 0.005) and they increased after weight loss (p < 0.001). At baseline, vitamin D blood concentrations of the persons with obesity were significantly correlated with both fat mass–kg (r = −0.40; p < 0.05) and body mass index (r = −0.47; p < 0.01). Following very low-calorie ketogenic diet, the change in vitamin D serum concentrations was correlated only with the change in fat mass–kg (r = −0.43; p < 0.01). Conclusion: This study confirmed that patients with obesity have lower vitamin D levels that normalize after significant weight loss, supporting the hypothesis that vitamin D is stored in the adipose tissue and released following weight loss.  相似文献   
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During the last 20 years, various conservative surgical techniques have been proposed to treat larynx cancer. On the basis of our various experiences and of the ultrastructural data on the tissues treated with radiowaves, we decided to also use radiosurgery in operations under direct microlaryngoscopy. We select 18 patients suffering from epidermoid carcinoma. These patients had been referred to our ENT clinic at the Polichnico of Palermo between 1999 and 2001. The authors describe the surgical procedures used and emphasize the advantages of radiosurgery in the treatment of larynx cancer.  相似文献   
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