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91.

Background

Histamine regulates function of osteoclasts and osteoblasts, however data regarding the influence of histamine H2 receptors antagonists on bone tissue are ambiguous. Factors that influence growing skeleton may have an important impact on the peak bone mass and future risk of fractures. The aim of our study was the assessment of influence of ranitidine, on growing bones.

Methods

The experiment was carried out on young male Wistar rats divided into two groups receiving either ranitidine (10 mg/kg ip) or vehicle.

Results

A significant decrease in femoral BMD in ranitidine-treated rats (R) compared to vehicle-treated ones (C) was detected (0.262 ± 0.009 g/cm2vs. 0.271 ±0.007 g/cm2, p < 0.05). In group R we observed elevated serum C-terminated telopeptide of type I collagen (CTX) level with concomitantly lowered serum osteocalcin (OC) concentration comparing to control group (151.2 ± 27.2 pg/ml vs. 101.5 ± 55.6, p < 0.05 and 229.1 ± 50.0 pg/ml vs. 292.0 ± 52.9, p < 0.05, respectively). Serum concentration of inorganic phosphorus was lower in group R than in group C (134 ± 13 mmol/L vs. 157 ± 28 mmol/L, p < 0.05).

Conclusions

Long-term administration of ranitidine increases bone resorption and decreases bone formation in growing rats leading to decrease in BMD.  相似文献   
92.
Tapentadol is a centrally acting analgesic with a dual mode of action as a μ-opioid receptor (MOR) agonist and a noradrenaline reuptake inhibitor (NRI). It was initially approved by the US Food and Drug Administration in November 2008 for the treatment of moderate-to-severe acute pain in adult patients, and in August 2011, for chronic pain in an prolonged release form in the same population. Due to its limited protein binding capacity, the absence of active metabolites and significant microsomal enzyme induction or inhibition, tapentadol has a limited potential for drug–drug interactions. It appears to be well-tolerated and effective in the treatment of moderate-to severe acute and chronic pain. Owing to its dual mechanism of action, it is hypothesized to be good option in the treatment of both nociceptive and neuropathic pain.  相似文献   
93.

Background

The removal of the olfactory bulbs has been attributed to behavioral changes and neuroplasticity manifesting themselves among others like increases in brain neurotrophin expression and neurogenesis. Earlier data presented that EMD386088, a 5-HT6 receptor partial agonist, exerts antidepressant-like properties after chronic administration in olfactory bulbectomy (OB) model as was it compared with amitriptyline (AMI). The aim of this study was to compare acute and chronic biochemical effects of EMD386088, administered in its antidepressant active (2.5 mg/kg) and non-active (1.25 mg/kg) doses, found in the open field test in OB rats, with those of AMI (10 mg/kg). The levels of 5-HT6 receptor protein and selected neurotrophins in prefrontal cortex (PFC) and hippocampus (Hp) of rats have been examined.

Methods

5-HT6 receptor protein and selected neurotrophins: brain-derived neurotrophic factor (BDNF), cAMP-response element binding protein (CREB), the product of the immediate early gene c-fos (cFos) protein levels were assessed using a Western blot analysis in PFC and Hp of bulbectomized rats after acute or chronic (14-day) EMD386088 or AMI intraperitoneal (ip) treatment.

Results

The acute treatment with EMD386088 caused significant increases in CREB and BDNF protein levels in PFC, and an increase in BDNF in Hp of OB rats, while AMI injection decreased CREB and did not change BDNF levels. After the chronic administration of EMD386088, the increasing levels of BDNF and CREB were still observed in PFC and Hp.

Conclusions

The antidepressant-like effect of EMD386088 may be associated with the neuroplasticity activation in PFC and Hp in rats.  相似文献   
94.

Objectives

To evaluate sensitization to chemicals present in work environment after an outbreak of contact dermatitis in workers of vehicle equipment factory, exposed to polyurethane foam, based on 4,4′-diphenylmethane diisocyanate (MDI).

Material and Methods

From among 300 employees, 21 individuals reporting work-related skin and/or respiratory tract symptoms underwent clinical examination, patch testing, skin prick tests, spirometry and MDI sIgE measurement in serum. Patch tests included isocyanates series, selected rubber additives, metals, fragrances, preservatives, and an antiadhesive agent.

Results

Clinical examination revealed current eczema in the area of hands and/or forearms in 10 workers. Positive patch test reactions were found in 10 individuals, the most frequent to diaminodiphenylmethane and 4-phenylenediamine (7 persons). Reactions to an antiadhesive agent were assessed as irritant (5 workers). Except for sensitization to common aeroallergens, no significant abnormalities were found in the remaining tests. Occupational allergic contact dermatitis was diagnosed in 7 workers, irritant contact dermatitis in 10 and coexisiting allergic and irritant contact dermatitis in 3 workers.

Conclusions

In workers manufacturing products from polyurethane foam, attention should be paid to the risk of developing contact dermatitis. Skin problems in our study group were attributable probably to insufficient protection of the skin.  相似文献   
95.

Objectives

Workers of X-ray departments are occupationally exposed to long-term low levels of ionizing radiation (LLIR), which may affect their humoral immunity. The aim of the study was to assess the influence of LLIR on the number and proportion of B cells (CD19+), B1 cells (CD5+CD19+) and memory B cells (CD27+CD19+) in peripheral blood of such workers.

Materials and Methods

In the study group of 47 X-ray departments workers and the control group consisting of 38 persons, the number and percentage of CD19+, CD5+CD19+, CD27+CD19+ cells as well as CD5+CD19+/CD19+ and CD27+CD19+/CD19+ cell ratios were assessed using flow cytometry. Additionally, the study group was divided into 2 groups by the length of employment below and over 15 years and analysis adjusted for age and smoking habit was performed.

Results

The total number of CD19+ cells showed significant increase in the group of workers in comparison with the persons from the control group, whereas the percentage of CD5+CD19+ cells as well as CD27+CD19+/CD19+ and CD5+CD19+/CD19+ cell ratios were lower. Percentage, number of CD5+CD19+ cells and CD5+CD19+/CD19+ cell ratio were significantly lower in the workers with length of employment longer than 15 years in comparison with those employed below 15 years. Moreover, we found positive associations between the number of CD19+ cells and employment as well as smoking habit, whereas the number of CD5+CD19+ cells was positively associated with cigarette smoking alone. Percentage of CD5+CD19+ cells as well as CD5+CD19+/CD19+ and CD27+CD19+/CD19+ cell ratios were negatively correlated with employment.

Conclusions

The study suggests association between the suppressive influence of low level ionizing radiation on circulating in peripheral blood, especially of B1 cells as well as of memory B cells, in workers of X-ray units, which is adverse in relation to microbiological threat.  相似文献   
96.
Abstract

Methanol and hexane extracts obtained from above-and below-ground organs of the cup plant Silphium perfoliatum. L. (Asteraceae) were analyzed by gas chromatography–mass spectrometry (GC-MS). Eighty-five components were identified in the extracts. Moreover, evaluation of the content of total secondary metabolites (flavonoids, o.-dihydroxyphenols, and glycoside-bonded oleanolic acid) was made in the methanol extract. It was found that leaf, inflorescence, and rhizome extracts of S. perfoliatum. were characterized by antibacterial action toward Gram-positive (Enterococcus faecalis., Staphylococcus aureus.) and Gram-negative (Escherichia coli., Pseudomonas aeruginosa. bacteria). All the extracts showed extremely high activity toward Staphylococcus aureus. FDA 209P strains (MIC values: 1.00 mg/mL for rhizome alcohol and hexane extracts; 2.50 mg/mL for leaf and inflorescence alcohol extracts and for leaf hexane extracts; 5.00 mg/mL for inflorescence hexane extracts). In general, alcohol extracts had slightly stronger antibacterial properties compared with lipophilic ones. Among the alcohol extracts, those made of S. perfoliatum. rhizomes had the highest activity compared with the leaf and inflorescence extracts.  相似文献   
97.
The purpose of this study was to determine the frequencies of hereditary and familial breast cancers among Lower Silesian women. The questionnaires, dealing with cancer episodes in first-and second-degree relatives, were sent to 5,000 females, who were diagnosed with breast cancer between 1984 and 2005. Twenty-five percent of the questionnaires were completed and returned. Their analysis and further counseling revealed that 24.9% of the responders met the criteria for familial breast cancer (FBC), including 10.5% definitive cases. Mutations in BRCA1 were detected in 32.5% and 1.9% of patients with definitive and suspected FBC, respectively. They all represented three of the abnormalities of the BRCA1 gene: 300T/G, 4153delA and 5382insC. No mutations of BRCA2 were found in material studied. Although a fraction of FBCs identified in our study was similar to those described in other European countries and in the United States, the percentages of genetic mutations seen on routine tests were relatively low. Consequently, the standardized analysis of oncological pedigree seems to be a more valuable diagnostic tool if patients with familial aggregations of breast cancer are targeted in a prophylactic context only.  相似文献   
98.
Bariatric surgery is the most effective method to achieve weight loss in obese subjects. The aim of this study was to evaluate some adipocytokines and insulin, as well as parameters of metabolic syndrome of the obese patients, for three and six months after vertical banded gastroplasty, in the time of dynamic weight loss. Seven males and two females aged 28 to 49 years, with long lasting simple obesity and the presence of metabolic syndrome, were studied. After surgical treatment the values of the body mass index, waist circumference, systolic and diastolic blood pressure, total cholesterol, LDL cholesterol, triglycerides, and blood concentrations of leptin decreased significantly. Before surgical operation of all obese patients no statistically significant correlations between studied parameters were noted. Three and six months later a lot of correlations between studied parameters appeared. In conclusion, (a) vertical-banded gastroplasty is a valuable method in treatment of obese subjects, leading to a significant decrease in body weight and improvement in some parameters of metabolic syndrome in a few months after surgery, (b) adipocytokines, together with an unknown gastric factor, may be key factors in the control of some features of the metabolic syndrome.  相似文献   
99.
The purpose of the present study was to demonstrate the epidemiological characteristics of colorectal cancers (CRCs) diagnosed in Lower Silesia between 1984 and 2003. Data from the Lower Silesian Cancer Registry on the incidence of CRC in the Lower Silesian province were subjected to analysis. The age adjusted incidence of CRC in both genders increased markedly. A higher relative increase of incidence was recorded for colon cancer. The age-specific incidence of either colon or rectal cancer increased markedly with age in both genders. No constant time-trend toward the earlier diagnosis of CRC was noted in the period studied. Although the number of CRC surgeries performed at the Regional Comprehensive Cancer Center in Wroclaw has increased over time, most of the cases that were diagnosed were treated outside that reference center. If an intensive increase in new case numbers, demonstrated in both the locations by 2003, is not moderated, the incidence of colorectal malignancies in Lower Silesia would become one of the highest in Europe.  相似文献   
100.
A series of N2-{2-[4-aryl(benzyl)-1-piperazinyl(piperidinyl)]ethyl}pyrrolo[3,4-d]pyridazinones 4 and related derivatives 5 were synthesized as potential analgesic agents. The structures of the new compounds were elucidated by micro, spectral and X-ray analysis. Analgesic activity of the compounds was investigated in the phenylbenzoquinone induced ‘writhing’ and ‘hot plate’ test in mice and at radioligand binding assay. At ‘writhing’ test all compounds, without exception, were more active than acetylsalicylic acid (ASA) with ED50 values ranging from 0.04 to 11 mg/kg (i.p.) (ED50 for ASA - 39.15 mg/kg). Analgesic effect at the ‘hot plate’ test was observed for three compounds 4c,e,f at the dose 3-5 times higher then that of morphine (ED50-3.39 mg/kg). At radioligand binding assay of 4c,e,f only compound 4f exhibited affinity for the μ-opioid receptors similar to that of Tramadol. The acute toxicity of the pyrrolopyridazinones 4, 5 were also studied and non toxic effect was observed at the 2000 mg/kg (5a 1420 mg/kg) i.p. dose level. On the basis of the available pharmacological data S-A relationship is discussed. The preferred conformational characteristic of 4, taken 4c as an example, was also described.  相似文献   
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