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21.
Human brucellosis is a significant public health problem in many Mediterranean countries including Greece. The conventional serological methods, as well as blood cultures, have serious limitations, especially in chronic, relapsing, and focal forms of the disease. Four different PCR assays were applied in 4,926 buffy coat, whole-blood, and serum samples received from 200 patients admitted with brucellosis to the Infectious Diseases Hospital, Thessaloniki, Greece, for the rapid diagnosis of acute infection and relapses and compared to blood culture and serological tests (i.e., Wright's seroagglutination test, Coombs' antibrucella test, and the complement fixation test). The four PCR assays had excellent sensitivity and specificity and were able to detect all of the cases of acute disease. Buffy coat and whole blood were the optimal specimens. All four PCR assays were negative in all follow-up samples from 183 patients who had completed a successful treatment and were positive in all follow-up samples from 17 patients who had relapses in the first year after therapy, including the times of the relapses. In conclusion, PCR is a very useful tool for the rapid diagnosis of acute brucellosis and a good marker for the posttreatment follow-up and the early detection of relapses.  相似文献   
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Arterial hypertension is considered a risk factor for erectile dysfunction. The aim of the study was to evaluate the prevalence of erectile dysfunction in hypertensive compared with normotensive individuals of similar demographic characteristics in Greece. Furthermore, the effect of age, hypertension severity, hypertension duration, and antihypertension medication on erectile function of these subjects was investigated. The study population consisted of 634 consecutive young and middle-aged men (31-65 years) that visited our outpatient clinic. From them, 358 patients had arterial hypertension and 276 were normotensive. Erectile dysfunction was evaluated with the International Index for Erectile Function questionnaire. Erectile dysfunction was found in 35.2% of patients with essential hypertension compared with 14.1% of normotensive subjects (chi(2) = 35.92, P < .001). Patients with essential hypertension had more severe erectile dysfunction than their normotensive counterparts (chi(2) = 17.1, P < .001). Hypertension duration, hypertension severity, antihypertension medication, and age were positively correlated with erectile dysfunction. The prevalence of erectile dysfunction is higher in patients with essential hypertension compared with normotensive subjects of similar demographic characteristics. Erectile dysfunction is related to age in both groups, whereas duration and severity of hypertension as well as antihypertension drugs affect erectile function of hypertensive patients. Erectile dysfunction affects patient quality of life, underlining the need for vigorous research of this condition and appropriate management.  相似文献   
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It has been hypothesized that chronic hyperinsulinemia, a major metabolic consequence of physical inactivity and excess weight, might increase breast cancer risk by direct effects on breast tissue or indirectly by increasing bioavailable levels of testosterone and estradiol. Within the European Prospective Investigation into Cancer and Nutrition (EPIC), we measured serum levels of C-peptide--a marker for pancreatic insulin secretion--in a total of 1,141 incident cases of breast cancer and 2,204 matched control subjects. Additional measurements were made of serum sex hormone binding globulin (SHBG) and sex steroids. Conditional logistic regression models were used to estimate breast cancer risk for different levels of C-peptide. C-peptide was inversely correlated with SHBG and hence directly correlated with free testosterone among both pre and postmenopausal women. C-peptide and free estradiol also correlated positively, but only among postmenopausal women. Elevated serum C-peptide levels were associated with a nonsignificant reduced risk of breast cancer diagnosed up to the age of 50 years [odds ratio (OR)=0.70, (95% confidence interval (CI), 0.39-1.24); ptrend=0.05]. By contrast, higher levels of C-peptide were associated with an increase of breast cancer risk among women above 60 years of age, however only among those women who had provided a blood sample under nonfasting conditions [OR=2.03, (95% CI, 1.20-3.43); ptrend=0.01]. Our results do not support the hypothesis that chronic hyperinsulinemia generally increases breast cancer risk, independently of age. Nevertheless, among older, postmenopausal women, hyperinsulinemia might contribute to increasing breast cancer risk.  相似文献   
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Rationale This review provides insight for the judicious selection of nicotine dose ranges and routes of administration for in vivo studies. The literature is replete with reports in which a dosaging regimen chosen for a specific nicotine-mediated response was suboptimal for the species used. In many cases, such discrepancies could be attributed to the complex variables comprising species-specific in vivo responses to acute or chronic nicotine exposure. Objectives This review capitalizes on the authors’ collective decades of in vivo nicotine experimentation to clarify the issues and to identify the variables to be considered in choosing a dosaging regimen. Nicotine dose ranges tolerated by humans and their animal models provide guidelines for experiments intended to extrapolate to human tobacco exposure through cigarette smoking or nicotine replacement therapies. Just as important are the nicotine dosaging regimens used to provide a mechanistic framework for acquisition of drug-taking behavior, dependence, tolerance, or withdrawal in animal models. Results Seven species are addressed: humans, nonhuman primates, rats, mice, Drosophila, Caenorhabditis elegans, and zebrafish. After an overview on nicotine metabolism, each section focuses on an individual species, addressing issues related to genetic background, age, acute vs chronic exposure, route of administration, and behavioral responses. Conclusions The selected examples of successful dosaging ranges are provided, while emphasizing the necessity of empirically determined dose–response relationships based on the precise parameters and conditions inherent to a specific hypothesis. This review provides a new, experimentally based compilation of species-specific dose selection for studies on the in vivo effects of nicotine.  相似文献   
26.
Barr AM  Fish KN  Markou A 《Neuropharmacology》2007,52(4):1114-1123
Postmortem brain loss of reelin is noted in schizophrenia patients. Accordingly, heterozygous reeler mutant mice have been proposed as a putative model of this disorder. Little is known, however, about the involvement of the two receptors for reelin, Very-Low-Density Lipoprotein Receptor (VLDLR) and Apolipoprotein E Receptor 2 (ApoER2), on pre-cognitive processes of relevance to deficits seen in schizophrenia. Thus, we evaluated sensorimotor gating in mutant mice heterozygous or homozygous for the two reelin receptors. Mutant mice lacking one of these reelin receptors were tested for prepulse inhibition (PPI) of the acoustic startle reflex prior to and following puberty, and on a crossmodal PPI task, involving the presentation of acoustic and tactile stimuli. Furthermore, because schizophrenia patients show increased sensitivity to N-methyl-d-aspartate (NMDA) receptor blockade, we assessed the sensitivity of these mice to the PPI-disruptive effects of the NMDA receptor antagonist phencyclidine. The results demonstrated that acoustic PPI did not differ between mutant and wildtype mice. However, VLDLR homozygous mice displayed significant deficits in crossmodal PPI, while ApoER2 heterozygous and homozygous mice displayed significantly increased crossmodal PPI. Both ApoER2 and VLDLR heterozygous and homozygous mice exhibited greater sensitivity to the PPI-disruptive effects of phencyclidine than wildtype mice. These results indicate that partial or complete loss of either one of the reelin receptors results in a complex pattern of alterations in PPI function that includes alterations in crossmodal, but not acoustic, PPI and increased sensitivity to NMDA receptor blockade. Thus, reelin receptor function appears to be critically involved in crossmodal PPI and the modulation of the PPI response by NMDA receptors. These findings have relevance to a range of neuropsychiatric disorders that involve sensorimotor gating deficits, including schizophrenia.  相似文献   
27.
BACKGROUNDHepatectomy with inflow occlusion results in ischemia-reperfusion injury; however, pharmacological preconditioning can prevent such injury and optimize the postoperative recovery of hepatectomized patients. The normal inflammatory response after a hepatectomy involves increased expression of metalloproteinases, which may signal pathologic hepatic tissue reformation. AIMTo investigate the effect of desflurane preconditioning on these inflammatory indices in patients with inflow occlusion undergoing hepatectomy.METHODSThis is a single-center, prospective, randomized controlled trial conducted at the 4th Department of Surgery of the Medical School of Aristotle University of Thessaloniki, between August 2016 and December 2017. Forty-six patients were randomized to either the desflurane treatment group for pharmacological preconditioning (by replacement of propofol with desflurane, administered 30 min before induction of ischemia) or the control group for standard intravenous propofol. The primary endpoint of expression levels of matrix metalloproteinases and their inhibitors was determined preoperatively and at 30 min posthepatic reperfusion. The secondary endpoints of neutrophil infiltration, coagulation profile, activity of antithrombin III (AT III), protein C (PC), protein S and biochemical markers of liver function were determined for 5 d postoperatively and compared between the groups.RESULTSThe desflurane treatment group showed significantly increased levels of tissue inhibitor of metalloproteinases 1 and 2, significantly decreased levels of matrix metalloproteinases 2 and 9, decreased neutrophil infiltration, and less profound changes in the coagulation profile.  During the 5-d postoperative period, all patients showed significantly decreased activity of AT III, PC and protein S (vs baseline values, P < 0.05). The activity of AT III and PC differed significantly between the two groups from postoperative day 1 to postoperative day 5 (P < 0.05), showing a moderate drop in activity of AT III and PC in the desflurane treatment group and a dramatic drop in the control group. Compared to the control group, the desflurane treatment group also had significantly lower international normalized ratio values on all postoperative days (P < 0.005) and lower serum glutamic oxaloacetic transaminase and serum glutamic pyruvic transaminase values on postoperative days 2 and 3 (P < 0.05).   Total length of stay was significantly less in the desflurane group (P = 0.009).CONCLUSIONDesflurane preconditioning can lessen the inflammatory response related to ischemia-reperfusion injury and may shorten length of hospitalization.  相似文献   
28.

Objectives

An immunohistological study of an infected immature permanent human tooth after a regenerative endodontic procedure (REP) was conducted in order to determine the histologic outcome of this procedure. Besides observed signs of angiogenesis and neurogenesis, repair and/or regeneration of the pulp-dentin complex was also investigated.

Materials and methods

A REP was performed on tooth 45 of a 10-year-old girl. Eleven months post-treatment, the tooth had to be removed for orthodontic reasons. The following investigations were performed: immunohistology and radiographic quantification of root development. After hematoxylin-eosin (HE) staining, the following immunomarkers were selected: neurofilament (NF), pan cytokeratin (PK), osteocalcin (OC), and CD34.

Results

The REP resulted in clinical and radiographic healing of the periradicular lesion and quantifiable root development. The HE staining matches with the medical imaging post-REP: underneath the mineral trioxide aggregate a calcified bridge with cell inclusions, connective pulp-like tissue (PLT) with blood vessels, osteodentin against the root canal walls, on the root surface cementum (Ce), and periodontal ligament (PDL). The PDL was PK+. The blood vessels in the PLT and PDL were CD34+. The Ce, osteodentin, and stromal cells in the PLT were OC+. The neurovascular bundles in the PLT were NF+.

Conclusions

Immunohistologically, REP of this infected immature permanent tooth resulted in an intracanalar connective tissue with a regulated physiology, but not pulp tissue.

Clinical relevance

REP of an immature permanent infected tooth may heal the periapical infection and may result in a combination of regeneration and repair of the pulp-dentin complex.
  相似文献   
29.
A fatal case is reported of Balantidium coli pneumonia in a 71-y-old woman suffering from anal cancer. The diagnosis was made by the discovery of motile trophozoites in a wet mount from bronchial secretions. The usual habitat of the parasite is the colon; lung balantidiasis is very rare.  相似文献   
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