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101.
102.
AIM: To compare the site, age and gender of cases of colorectal cancer (CRC) and polyps in a single referral center in Rome, Italy, during two periods.METHODS: CRC data were collected from surgery/pathology registers, and polyp data from colonoscopy reports. Patients who met the criteria for familial adenomatous polyposis, hereditary non-polyposis colorectal cancer syndrome or inflammatory bowel disease were excluded from the study. Overlap of patients between the two groups (cancers and polyps) was carefully avoided. The χ2 statistical test and a regression analysis were performed.RESULTS: Data from a total of 768 patients (352 and 416 patients, respectively, in periods A and B) who underwent surgery for cancer were collected. During the same time periods, a total of 1693 polyps were analyzed from 978 patients with complete colonoscopies (428 polyps from 273 patients during period A and 1265 polyps from 705 patients during period B). A proximal shift in cancer occurred during the latter years for both sexes, but particularly in males. Proximal cancer increased > 3-fold in period B compared to period A in males [odds ratio (OR) 3.31, 95%CI: 2.00-5.47; P < 0.0001). A similar proximal shift was observed for polyps, particularly in males (OR 1.87, 95%CI: 1.23-2.87; P < 0.0038), but also in females (OR 1.62, 95%CI: 0.96-2.73; P < 0.07).CONCLUSION: The prevalence of proximal proliferative colonic lesions seems to have increased over the last decade, particularly in males.  相似文献   
103.
Summary. Background: A pulmonary embolism (PE) is thought to be associated with atrial fibrillation (AF). Nevertheless, this association is based on weak data. Objectives: To assess whether the presence of AF influences the clinical probability of PE in a cohort of patients with suspected PE and to confirm the association between PE and AF. Patients/methods: We retrospectively analyzed the data from two trials that included 2449 consecutive patients admitted for a clinically suspected PE. An electrocardiography (ECG) was systematically performed and a PE was diagnosed by computer tomography (CT). The prevalence of AF among patients with or without a PE was compared in a multivariate logistic regression model. Results: The prevalence of PE was 22.8% (519/2272) in patients without AF and 18.8% (25/133) in patients with AF (P = 0.28). After adjustment for confounding factors, AF did not significantly modify the probability of PE (odds ratio [OR] 0.68, 95% confidence interval [CI] 0.42–1.11). However, when PE suspicion was based on new‐onset dyspnea, AF significantly decreased the probability of PE (OR 0.47, 95% CI 0.26–0.84). If isolated chest pain without dyspnea was the presenting complaint, AF tended to increase the probability of PE (OR 2.42, 95% CI 0.97–6.07). Conclusions: Overall, the presence of AF does not increase the probability of PE when this diagnosis is suspected. Nevertheless, when PE suspicion is based on new‐onset dyspnea, AF significantly decreases the probability of PE, as AF may mimic its clinical presentation. However, in patients with chest pain alone, AF tends to increase PE probability.  相似文献   
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Antivirulence strategies targeting bacterial behavior, such as adhesion and biofilm formation, are expected to exert low selective pressure and have been proposed as alternatives to biocidal antibiotic treatments to avoid the rapid occurrence of bacterial resistance. Here, we tested this hypothesis using group 2 capsule polysaccharide (G2cps), a polysaccharidic molecule previously shown to impair bacterium-surface interactions, and we investigated the nature of bacterial resistance to a nonbiocidal antibiofilm strategy. We screened an Escherichia coli mutant library for an increased ability to form biofilm in the presence of G2cps, and we identified several mutants displaying partial but not total resistance to this antibiofilm polysaccharide. Our genetic analysis showed that partial resistance to G2cps results from multiple unrelated mutations leading to modifications in surface physicochemical properties that counteract the changes in ionic charge and Lewis base properties induced by G2cps. Moreover, some of the identified mutants harboring improved biofilm formation in the presence of G2cps were also partially resistant to other antibiofilm molecules. This study therefore shows that alterations of bacterial surface properties mediate only partial resistance to G2cps. It also experimentally validates the potential value of nonbiocidal antibiofilm strategies, since full resistance to antibiofilm compounds is rare and potentially unlikely to arise in clinical settings.  相似文献   
106.

Purpose of Review

This review aims to examine gender differences in both the epidemiology and pathophysiology of hypertension and to explore gender peculiarities on the effects of antihypertensive agents in decreasing BP and CV events.

Recent Findings

Men and women differ in prevalence, awareness, and control rate of hypertension in an age-dependent manner. Studies suggest that sex hormones changes play a pivotal role in the pathophysiology of hypertension in postmenopausal women. Estrogens influence the vascular system inducing vasodilatation, inhibiting vascular remodeling processes, and modulating the renin-angiotensin aldosterone system and the sympathetic system. This leads to a protective effect on arterial stiffness during reproductive age that is dramatically reversed after menopause.

Summary

Data on the efficacy of antihypertensive therapy between genders are conflicting, and the underrepresentation of aged women in large clinical trials could influence the results. Therefore, further clinical research is needed to uncover potential gender differences in hypertension to promote the development of a gender-oriented approach to antihypertensive treatment.
  相似文献   
107.
BACKGROUND: Mixed cryoglobulinemia (MC) is a systemic vasculitis secondary to circulating immune complex deposition in the small vessels. In the overwhelming majority of patients, hepatitis C virus (HCV) infection represents the triggering factor of the disease. MC is characterized by multiple organ involvement, mainly skin, liver, renal, peripheral nerves, and less frequently by widespread vasculitis and cancer. OBJECTIVES: To investigate the demographic, clinical, serologic features, and survival in a large series of MC patients. METHODS: The study included 231 MC patients recruited between 1972 and 2001 at the Rheumatology Unit of the University of Pisa. All patients underwent wide clinicoserologic and virologic assessment. Cumulative survival rates were computed by the Kaplan-Meier method; moreover, the prognostic relevance of the main variables was investigated by Cox model analysis. RESULTS: In 92% of cases, the presence of HCV infection was demonstrated (anti-HCV antibody, 92%; HCV RNA, 90%), whereas hepatitis B virus (HBV) represented the possible causative agent in only 1.8% of patients (HBV DNA). Clinically, the MC syndrome followed a relatively benign clinical course in over 50% of cases, whereas a moderate-severe clinical course was observed in one third of patients whose prognosis was severely affected by renal and/or liver failure. In a limited, but significant, percentage (15%) of individuals, the disease was complicated by a malignancy, ie, B-cell lymphoma, and less frequently by hepatocellular carcinoma, or thyroid cancer. The survival study by the Kaplan-Meier method revealed a significantly lower cumulative 10th-year survival, calculated from time of diagnosis, in MC patients compared with expected death in the age- and sex-matched general population. Moreover, significantly lower survival rates were observed in males and in subjects with renal involvement. The multivariate analysis by the Cox proportional hazard regression model further supported the above findings: an increased mortality risk of 98% was observed for male gender (male/female hazard ratio, 1.978) and of 197% in patients with, compared with those without, renal involvement (hazard ratio, 2.967). At the end of the follow-up, 97 patients were deceased, and in 79 of 97 patients, the causes of death were ascertained: nephropathy (33%), malignancies (23%), liver involvement (13%), and diffuse vasculitis (13%) were the most frequent causes of death. CONCLUSIONS: Careful patient monitoring is recommended for a timely diagnosis of life-threatening MC complications, mainly nephropathy, widespread vasculitis, and B-cell lymphoma or other malignancies.  相似文献   
108.
Bone marrow examination revealed a lipid-laden histiocytosis in seven patients undergoing long-term total parenteral nutrition necessitated by extensive short-bowel surgical resection. Clinical abnormalities occurred during this treatment which required bone marrow examination. These included hepatosplenomegaly and peripheral blood cytopenia; the median time to the detection of these abnormalities was 64 months.   The most striking change within the bone marrow was the presence of many pigment-laden histiocytes which had the typical morphology of sea-blue histiocytes seen in the so-called idiopathic sea-blue histiocyte syndrome. The occurrence of sea-blue histiocytosis in the bone marrow in association with long-term parenteral nutrition for short-bowel syndrome has not, to our knowledge, been reported previously and should now be considered in the differential diagnosis of bone marrow sea-blue histiocytosis.  相似文献   
109.
110.
Loss-of-function variants in ANKRD11 were identified as the cause of KBG syndrome, an autosomal dominant syndrome with specific dental, neurobehavioural, craniofacial and skeletal anomalies. We present the largest cohort of KBG syndrome cases confirmed by ANKRD11 variants reported so far, consisting of 20 patients from 13 families. Sixteen patients were molecularly diagnosed by Sanger sequencing of ANKRD11, one familial case and three sporadic patients were diagnosed through whole-exome sequencing and one patient was identified through genomewide array analysis. All patients were evaluated by a clinical geneticist. Detailed orofacial phenotyping, including orthodontic evaluation, intra-oral photographs and orthopantomograms, was performed in 10 patients and revealed besides the hallmark feature of macrodontia of central upper incisors, several additional dental anomalies as oligodontia, talon cusps and macrodontia of other teeth. Three-dimensional (3D) stereophotogrammetry was performed in 14 patients and 3D analysis of patients compared with controls showed consistent facial dysmorphisms comprising a bulbous nasal tip, upturned nose with a broad base and a round or triangular face. Many patients exhibited neurobehavioural problems, such as autism spectrum disorder or hyperactivity. One-third of patients presented with (conductive) hearing loss. Congenital heart defects, velopharyngeal insufficiency and hip anomalies were less frequent. On the basis of our observations, we recommend cardiac assessment in children and regular hearing tests in all individuals with a molecular diagnosis of KBG syndrome. As ANKRD11 is a relatively common gene in which sequence variants have been identified in individuals with neurodevelopmental disorders, it seems an important contributor to the aetiology of both sporadic and familial cases.  相似文献   
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