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41.
42.
Carbamate derivatives of N-propargylaminoindans (Series I) and N-propargylphenethylamines (Series II) were synthesized via multistep procedures from the corresponding hydroxy precursors. The respective rasagiline- and selegiline-related series were designed to combine inhibitory activities of both acetylcholine esterase (AChE) and monoamine oxidase (MAO) by virtue of their carbamoyl and propargylamine pharmacophores. Each compound was tested for these activities in vitro in order to find molecules with similar potencies against each enzyme. Compounds with such dual AChE and MAO inhibitory activities are expected to have potential for the treatment of Alzheimer's disease. The observed SAR also offers insight into the requirements of the active sites on these enzymes. A carbamate moiety was found to be essential for AChE inhibition, which was absent in the corresponding hydroxy precursors. The propargyl group caused 2-70-fold decrease in AChE inhibitory activity (depending on the position of the carbamoyl group) of Series I, but had little or no effect in Series II. Thus, the 6- and 7-carbamyloxyphenyls in Series I were either equipotent to, or slightly (2- to 5-fold) less active as AChE inhibitors than, the corresponding compounds in Series II, while the 4-carbamyloxyphenyls were more potent. The presence of the carbamate moiety in 6- and 7-carbamyloxyphenyls of Series I, considerably decreased MAO-A and -B inhibitory activity, compared to that of the parent hydroxy analogues, while the opposite was true for Series II. Thus, the 6- and 7-carbamyloxyphenyls in Series I were 2-3 orders of magnitude weaker MAO inhibitors while the 4- carbamyloxyphenyls were equipotent with the corresponding compounds in Series II. In both series, N-methylation of the propargylamine enhanced the MAO (A and B equally) inhibitory activities and decreased the AChE inhibitory activity. Two candidates belonging to the indan and tetralin ring systems (24c, 27b) and one phenethylamine (53d) were identified as possible leads for further development based on the following criteria: (a) comparable AChE and MAO-B inhibitory activities, (b) good to moderate AChE inhibitory activity, and (c) lack of strong MAO-A selectivity. However, it is likely that these compounds will be metabolized to the corresponding phenols, with inhibitory activities against AChE and/or MAO-A or -B, different from those of the parent carbamates. Thus, the apparent enzyme inhibition will be a result of the combined inhibition of all of these individual metabolites. The results of our ongoing in vivo screening programs will be published elsewhere.  相似文献   
43.
Secretion of mucins and exudation of plasma are distinct processes of importance to innate immunity and inflammatory disease. Yet, little is known about their relation in human airways. The objective of the present study was to use the human nasal airway to determine mucinous secretion and plasma exudation in response to common challenge agents and mediators. Ten healthy volunteers were subjected to nasal challenge-lavage procedures. Thus, the nasal mucosa was exposed to increasing doses of histamine (40 and 400 microg ml(-1)), methacholine (12.5 and 25 mg) and capsaicin (30 and 300 ng ml(-1)). Fucose was selected as a global marker of mucinous secretion and alpha(2)-macroglobulin as an index of exudation of bulk plasma. All challenge agents increased the mucosal output of fucose to about the same level (P<0.01-0.05). Once significant secretion had been induced the subsequently increased dose of the challenge agent, in the case of histamine and methacholine, failed to further increase the response. Only histamine increased the mucosal output of alpha(2)-macroglobulin (P<0.01). We conclude that prompt but potentially rapidly depleted mucinous secretion is common to different kinds of airway challenges, whereas inflammatory histamine-type mediators are required to produce plasma exudation. Along with the acknowledged secretion of mucins, a practically non-depletable, pluripotent mucosal output of plasma emerges as an important component of the innate immunity of human airways.  相似文献   
44.

Aim

To collect cancer epidemiology data in South Eastern European countries as a basis for potential comparison of their performance in cancer care.

Methods

The South Eastern European Research Oncology Group (SEEROG) collected and analyzed epidemiological data on incidence and mortality that reflect cancer management in 8 countries – Croatia, Czech Republic, Hungary, Romania, Poland, Slovakia, and Serbia and Montenegro in the last 20-40 years.

Results

The most common cancer type in men in all countries was lung cancer, followed by colorectal and prostate cancer, with the exception of the Czech Republic, where prostate cancer and colorectal cancer were more common. The most frequent cancer in women was breast cancer followed by colorectal cancer, with the exceptions of Romania and Central Serbia where cervical cancer was the second most common. Cancer mortality data from the last 20-40 years revealed two different patterns in men. In Romania and in Serbia and Montenegro, there was a trend toward an increase, while in the other countries mortality was declining, after increasing for a number of years. In women, a steady decline was observed over many years in the Czech Republic, Hungary, and Slovakia, while in the other countries it remained unchanged.

Conclusions

There are striking variations in the risk of different cancers by geographic area. Most of the international variation is due to exposure to known or suspected risk factors which provides a clear challenge to prevention. There are some differences in incidence and mortality that cannot be explained by exposure to known risk factors or treatment availabilities.On a global scale, cancer has become a major public health problem and an increasingly important contributor to the burden of disease. Based on the most recent available international data, there were an estimated 12.7 million new cancer cases, 7.6 million deaths from cancer, and 28 million persons alive with cancer within five years from the initial diagnosis (1-3). The most common cancers in the world were lung (1.61 million cases), breast (1.38 million), and colorectal cancer (1.24 million) (3). Because of its poor prognosis, lung cancer was also the most common cause of death (1.38 million), followed by gastric (737 000 deaths), and liver cancer (695 000 deaths) (1-4).Priority setting for cancer control and cancer services in any region needs to be based on knowledge of the cancer burden and the local mix of predominant cancer types (5). According to estimates of global cancer burden made by the International Agency for Research on Cancer (IARC), the incidence and mortality rates from many specific types of cancer and all cancers combined vary widely by geographic locality (6). Moreover, the IARC also estimated that over half of newly diagnosed cases and two-thirds of cancer deaths occur in low and medium-income countries (6). There are striking variations in the pattern of cancer by site from region to region (7). The large differences in incidence and mortality in different countries may reflect a combination of differences in prevalence of underlying risk factors, differences in host susceptibility, and/or variations in cancer detection, reporting, classification systems, treatment, and follow-up. Among European countries, wide differences in the quality of cancer care are observed, especially when comparison is made between “old” and “new” EU members or between developed and developing countries (8). Cancer survival is significantly lower in Eastern European countries, including the new Member States, than in the EU 15 (9-12). Transitional countries and middle income countries are frequently left forgotten “in between” and the cancer problem in these countries is among the worst and fastest growing (8).In this report, we provide an analysis, which we propose as a foundation for detailed evaluation of cancer care in selected Central, Southern and Eastern European countries, represented by members of the South Eastern European Research Oncology Group (SEEROG). Our epidemiological analysis indicates the scale of the problem of oncological care in individual countries and shows current trends in the incidence of particular cancers. Comparison of status of oncology between countries in Eastern, Southern, and Central European region has never been undertaken before and key barriers to deliver appropriate quality of care have not previously been identified.  相似文献   
45.
This article describes the history, structure, and contributions of the Center for Prostate Disease Research. It divides the organization into the clinical program at Walter Reed Army Medical Center, the basic science program in Rockville, MD, and the multi-center national database. The emphasis of this article is not the achievements of the individual programs but their synergy, establishing a comprehensive multidisciplinary prostate center.  相似文献   
46.
Genes involved in sex hormone pathways are candidates for influencing bone strength. Polymorphisms in these genes were tested for association with heel quantitative ultrasound (QUS) parameters in middle‐aged and elderly European men. Men 40–79 yr of age were recruited from population registers in eight European centers for the European Male Aging Study (EMAS). Polymorphisms were genotyped in AR, ESR1, ESR2, CYP19A1, CYP17A1, SHBG, SRD5A2, LHB, and LHCGR. QUS parameters broadband ultrasound attenuation (BUA) and speed of sound (SOS) were measured in the heel and used to derive BMD. The relationships between QUS parameters and polymorphisms were assessed using linear regression adjusting for age and center. A total of 2693 men, with a mean age of 60.1 ± 11.1 (SD) yr were included in the analysis. Their mean BUA was 80.0 ± 18.9 dB/Mhz, SOS was 1550.2 ± 34.1 m/s, and BMD was 0.542 ± 0.141 g/cm2. Significant associations were observed between multiple SNPs in a linkage disequilibrium (LD) block within CYP19A1, peaking at the TCT indel with the deletion allele associating with reduced ultrasound BMD in heterozygotes (β =?0.016, p = ?0.005) and homozygotes (β = ?0.029, p = 0.001). The results for BUA and SOS were similar. Significant associations with QUS parameters were also observed for the CAG repeat in AR and SNPs in CYP17A1, LHCGR, and ESR1. Our data confirm evidence of association between bone QUS parameters and polymorphisms in CYP19A1, as well as modest associations with polymorphisms in CYP17A1, ESR1, LHCGR, and AR in a population sample of European men; this supports a role for genetically determined sex hormone actions in influencing male bone health.  相似文献   
47.
Increased levels of soluble P-selectin (sP-selectin) have been shown in a number of different disorders, e.g. diabetes mellitus (DM) and cardiovascular disease (CVD). Several studies have attempted to demonstrate the association of the most intensively examined variant of P-selectin gene polymorphism (Thr715Pro) with sP-selectin levels in healthy subjects and in CVD, but contradictory data have been reported. To clarify the effect of Pro715 allele on the sP-selectin levels in type 2 DM, we analysed this polymorphism in diabetic patients and compared these data with sP-selectin levels. Type 2 DM patients (n = 119), 48 BMImatched non diabetic individuals - consisting mostly of overweight subjects - and 57 healthy volunteers were included in the study. TheThr715Pro polymorphism was analysed by PCR-RFLP, while sP-selectin levels were measured by ELISA. Significantly elevated sP-selectin levels were found in both DM and in overweight subjects compared to healthy controls. We confirmed previous reports that in healthy Pro715 allele carriers lower sPselectin levels could be measured; however, this difference was only significant in case of lean subjects. No significant difference was detected in sP-selectin level among DM and overweight individuals according to this genotype. However, significant difference was observed in sP-selectin levels in older DM patients compared to younger ones, but these levels were not accounted for by the Thr715Pro polymorphism. We suggest that in type 2 DM individuals, the significantly elevated sP-selectin levels are not due to the Thr715Pro P-selectin gene polymorphism.  相似文献   
48.
The purpose of this study was to investigate whether detectable protein biomarker overexpression is a prerequisite for the presence of increased gene copy number or activating mutations and responsiveness to the epidermal growth factor receptor (EGFR) inhibitors gefitinib and erlotinib in patients with lung adenocarcinomas. EGFR status was prospectively analyzed in tumor biopsy samples by three methods: protein expression (n = 117) by standardized immunohistochemistry (IHC), gene copy number (n = 97) by fluorescent in situ hybridization (FISH), and mutation analysis by sequencing (n = 126). Fifty-nine percent of the samples were positive by IHC, 40% were positive by FISH, and 13.5% contained activating kinase domain mutations. Thirty-four percent of the FISH-positive and 27% of the mutant samples were also IHC-negative. All EGFR mutant patients had major clinical responses (five complete response and five partial response) to gefitinib or erlotinib treatment, although three of these tumors were IHC-negative and four were FISH-negative. In a retrospective analysis of samples from nine patients with excellent therapeutic responses (three complete response, five partial response, one stable disease) to erlotinib or gefitinib, mutations were identified in eight cases, but IHC was negative in four of these tumors. These results indicate that molecular diagnostic methods appear to be most important for the identification of lung adenocarcinoma patients who may benefit from EGFR inhibitor treatments.  相似文献   
49.
In this paper, the authors report on a new, modified laparoscopic technique to remove a large bladder diverticulum. A 26-year-old male with a urinary problem underwent an ultrasound, as well as intravenous urography and cystoscopy examinations, which showed a large bladder diverticulum. The diverticulum was operated upon laparoscopically. The extraperitoneal laparoscopic intervention was facilitated by balloon placed into the diverticulum. The new technique for the laparoscopic diverticulumectomy procedure was successful and the operating time was 140 minutes. There were no perioperative complications. In conclusion, the laparoscopic removal of the bladder diverticulum is a safe and minimally invasive intervention. The introduction of a balloon into the diverticulum makes the operation easier.  相似文献   
50.
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