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1.
A microassay requiring as few as 2 X 10(5) cells per assay was developed for systematic analysis of 9 purine enzymes in lymphocytes from equine peripheral blood, spleen, lymph node, thymus and bone marrow. The activities of adenosine deaminase (ADA), purine nucleoside phosphorylase (PNP), adenosine kinase (AK), deoxyadenosine kinase (dAK), deoxycytidine kinase (dCK), 5'-nucleotidase (5'-N), AMP deaminase, hypoxanthine-guanine phosphoribosyl transferase (HGPRT or HPRT), and adenine phosphoribosyl transferase (APRT) were measured by this microassay in lymphocytes from peripheral blood from four different breeds of horses (Arabian, Quarter Horse, Thoroughbred and Shetland Pony). There were no significant differences in the enzyme activities among the various breeds. Peripheral blood lymphocytes (PBL) from foals exhibited enzyme activities similar to those observed for adult animals. All lymphoid tissue contained similar levels of activity for each kinase (AK, dAK and dCK). Spleen had the highest activity for ADA, PNP, 5'-N, and HGPRT. The lowest activity for ADA, APRT, PNP and AMP deaminase was found in thymus. Enzymatic activities that varied the most among the tissue were 5'-N, ADA, APRT, HGPRT and AMP deaminase.  相似文献   

2.
Activities of adenosine deaminase (ADA), adenosine kinase (AK), adenine phosphoribosyltransferase (APRT), hypoxanthine guanine phosphoribosyltransferase (HGPRT), and purine nucleoside phosphorylase (PNP), all enzymes of the purine interconversion system, were determined in lymphocytes of 25 patients with chronic lymphatic leukemia (CLL) and in 23 controls. A statistically significant decrease of PNP activities and a reduction of ADA activities at borderline levels were found in the patients, whereas for the other enzymes assayed no deviation from normal values was observed.  相似文献   

3.
Heroin affects purine nucleotides catabolism in rats in vivo   总被引:7,自引:0,他引:7  
Yang YD  Zhang JZ  Sun C  Yu HM  Li Q  Hong M 《Life sciences》2006,78(13):1413-1418
To investigate the effect of heroin on purine nucleotides catabolism, a rat model of heroin administration and withdrawal was established. Concentrations of uric acid, creatinine, and urea nitrogen in plasma and ADA in plasma, brain, liver, and small intestine were tested. When two heroin administration groups were compared with the control group, the concentrations of plasma uric acid and ADA in plasma, brain, liver, and small intestine increased, whereas the plasma urea nitrogen concentrations in two heroin administration groups and the plasma creatinine concentration in the 3-day heroin administration group did not increase. It seemed that heroin exposure for a short time did not affect renal clearance rate notably. When two withdrawal groups were compared with two heroin administration groups, the concentrations of plasma uric acid and ADA in liver and small intestine decreased, but there was no significant reduction in ADA concentrations of the brain, while the plasma ADA concentrations in the two withdrawal groups were significantly higher than those of two heroin administration groups. When the two withdrawal groups were compared with the control group, there was no significant difference in the concentrations of plasma uric acid and ADA in liver and small intestine, while the concentrations of ADA in plasma and brain were still higher than those of the control group. The results imply that heroin administration may enhance the catabolism of purine nucleotides in the brain and other tissues by increased concentration of ADA and the effect may last for a long time in the brain.  相似文献   

4.

Background

It is well-known that tumor exerts nonmetastatic systemic effect on organism caused the development of paraneoplastic syndrome (PNS). Recent findings point to relationships between development of PNS and tumor-derived vascular endothelial growth factor (VEGF).

Aim

Comparative study of PNS manifestations in mice with transplanted two variants of Lewis lung carcinoma with different angiogenic potential.

Methods

Plasma VEGF level was determined by immunoenzyme method, hematological indices were estimated with the use of hematological analyzer, the weight and cellularity of spleen and thymus were registered and histological analysis of tissue section of these organs was performed.

Results

Manifestations of anemia, extramedullary hemopoiesis and tumor-associated inflammatory disease was observed in animals with high angiogenic LLC/R9 variant and was not registered in low angiogenic LLC. The emergence of PNS symptoms correlated with elevated level of circulating VEGF at the early stages of LLC/R9 growth.

Conclusion

Manifestation of the paraneoplastic hematological syndrome most likely is conditioned on the ability of cancer cell to secrete VEGF in a high rate.  相似文献   

5.

Objectives

This study provides psychometric data for the Spanish adaptation of the scale of Retirement Satisfaction Inventory (RSI). We explore the factor structure and psychometric properties a sample of Spanish early retirees. RSI measures the motivation to retirement, satisfaction with life in retirement and leisure activities.

Material and methods

The RSI scale (Floyd et al, 1992) was applied to a sample of 638 Spanish early-pensioners with a mean age of 61.28 (SD: 5.77) years and a mean age at early retirement of 53.89 years (SD: 2.71). An exploratory factorial analysis was performed using the SPSS statistics package, and a confirmatory factorial using the AMOS 6.0 module. The data collection process was carried out by means of the questionnaires by post method.

Results

The adaptation of the RSI to Spanish showed a three-scale structure:: the reasons for retirement, satisfaction with life in retirement, and leisure activities. These scales showed a structure with four, two and three main factors, respectively, which differ slightly from those reported in the original instrument.The confirmatory factorial analysis demonstrated the optimum fit of the model for the three scales.

Conclusions

The RSI adaptation to Spanish provides a tool that could asses the motivation towards retirement during the leaving work process, satisfaction with retirement life, and the leisure sources in the Spanish early retired population.  相似文献   

6.
Yadav D  Chandra R  Saxena R  Agarwal D  Agarwal M  Ghosh T  Agrawal D 《Gene》2011,487(2):166-169

Background

Difference in the capacity of xenobiotic metabolising enzymes might be an important factor in genetic susceptibility to cancer.

Methods

A case control study involving forty one gastric cancer patients and one hundred and thirty controls was carried out to determine the frequency of GSTM1 and GSTT1 null genotypes. The frequency of GSTM1 and GSTT1 null genotype was observed by carrying out multiplex PCR.

Results

There was no difference in the frequencies of the GSTM1 and GSTT1 null and the combined GSTM1 and GSTT1 null genotype between patients and control.

Conclusions

Our data suggest that GSTM1 and GSTT1 status may not influence the risk of developing gastric cancer.  相似文献   

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10.
Spontaneous and mutagen-induced 2,6-diaminopurine-resistant mutants of Chinese hamster ovary (CHO-K1) cells were isolated. Such mutants fell into two classes: spontaneous and ethylmethane-sulfonate-induced mutants had approximately 5% wild-type adenine phosphoribosyl transferase (APRT) activity, whereas ICR-170G-induced mutants had barely detectable APRT activity. Since it has been reported that human hypoxanthine-guanine phosphoribosyl transferase (HGPRT) (Lesch-Nyhan syndrome) and APRT mutants over-produce purines, we examined the control and rate of purine biosynthesis in the Chinese hamster mutants. End product inhibition by adenine could not be demonstrated in such mutants, indicating that the active feedback inhibitor is a nucleotide rather than the free purine base, HGPRT activity was normal in all mutants examined except in one isolate. Purine biosynthesis as measured by the accumulation of the purine biosynthetic intermediate phosphoribosyl formylglycineamide was not elevated in the mutants as might have been predicted from work with Lesch-Nyhan cells. The data also suggest that our strain of CHO-K1 is physically or functionally haploid for the APRT locus.  相似文献   

11.
Activities of adenosine deaminase (ADA), 5′nucleotidase (5NT), xanthine oxidase (XO), superoxide dismutase (SOD), and catalase (CAT) enzymes were measured in cancerous and cancer-free adjacent bladder tissues from 36 patients.with bladder cancer and in control bladder tissues from 9 noncancer patients. Increased ADA and decreased XO, SOD, and CAT activities were found in cancerous bladder tissues compared with those of cancer-free adjacent tissues and of control bladder tissues. Differences were also found between enzyme activities in the bladder of different disease stages and grades. In the cancerous tissues, only positive intracorrelations were found, but in the cancer-free adjacent tissues and control tissues, both positive and negative correlations were established between enzyme activities. Results suggested that purine metabolism and salvage pathway activity of purine nucleotides were accelerated in the cancerous human bladder tissues via increased ADA and decreased XO activities, probably together with changes in some other related enzyme activities and, free radical metabolising-enzyme activities were depressed in cancerous bladder tissues, which indicated exposure of cancerous tissues to more radicalic stress.  相似文献   

12.

Introduction

Infection processes in gerontology centres (GC) are one of the main causes of mortality and aggravation of concomitant chronic diseases. An epidemiological surveillance system was set up to find out their magnitude and distribution.

Material and methods

A prevalence study was conducted during the years 2006-2009 in 4 GCs of the Matia Foundation. Prevalence was measured by making an annual cut-off, recording: infection type, demographic data, risk factors and antibiotic use. The incidence was measured for two years in one GC as a pilot centre, recording: infection type and antibiotic use.

Results

The prevalence in the GCs varied between 4.8% and 6.44%. The infection incidence density in the pilot study was between 3.45-5.77 infections per 1,000 resident days. The most common infection location and in this order were, respiratory, urinary and cutaneous. The incidence of respiratory infection is more statistically significant in the presence of dysphagia, malnutrition and COPD. However, no significant relationship was seen in the incidence of urinary infection with the different risk factors analysed.

Conclusions

The frequency and repercussions of nosocomial infections in GCs demonstrate the need for intervention plans and the development of adequate prevention measures.  相似文献   

13.
Tea, flavonoids and stroke in man and mouse   总被引:1,自引:0,他引:1  

Background and purpose

To evaluate the strength of the in vivo evidence of relationships between flavonoids and risk of stroke.

Methods

We reviewed the literature more broadly for flavonoids and stroke and conducted an evidence-based review of original publication experiments on tea or tea components on induced coronary occlusion in animal models and on the observational epidemiology on stroke and either tea or flavonoids in man. Each of the studies was evaluated by two independent reviewers. The evidence in total was compared with the Bradford Hill [1] and Stroke Therapy Academic Industry Roundtable (STAIR)1 quality-assessment criteria [2].

Results

The search of epidemiologic publications revealed 7 cohort studies on flavonoid intake and stroke and 7 cohort studies and 3 case control studies on tea and stroke. In studies of tea there was a consistent protective effect. However, the epidemiologic research on flavonoids and stroke was much less consistent. Eleven animal experiments were identified that examined tea or tea components and stroke relevant sequelae, eight of which reported on infarct volume. All studies demonstrated reduced infarct volumes in animals exposed either to tea extracts, theanine or tea catechins prior to or shortly after reperfusion.

Conclusions

Hill’s criteria of causality are largely met in the case of tea and stroke. A high level of consistency across preclinical studies, of the effect of tea components as single agents effective in reducing stroke volume after middle cerebral artery occlusion, is noted in all rodent models (rat, mouse, and gerbil). Reductions in infarct volume are seen with both tea extracts consumed orally and tea components introduced intra-peritoneally. Observational epidemiology supports this finding in man for tea - the studies are consistent across countries and type of tea and the relative risks are moderately strong. That is not the case for the body of evidence on flavonoid intakes and stroke.  相似文献   

14.
Chronic Obstructive Pulmonary Disease (COPD) is a progressive disease with dyspnoea perception as a main symptom. In severe stages, dyspnoea can constitute a risk factor for depression, anxiety and somatization disorders.

Objective

The objective was to evaluate the presence of these psychopathologies based on dyspnoea and severity stages in patients with COPD.

Materials and methods

Patients (n=51) were evaluated by means of the Hospital Anxiety and Depression Scale, the dyspnoea scale (MRC), the General Health Questionnaire (GHQ-28) and spirometric criteria.

Results

The increase in dyspnoea level and disease severity lead to a progressive worsening of anxiety, depressive and somatic symptoms with clinical relevance (P<0.05). There was a significant correlation between those parameters (P<0.05).

Conclusions

The early detection and treatment of these psychopathologies associated with dyspnoea and progression of the disease must be taken into account in this complex pathology.  相似文献   

15.
16.

Background

Frailty is a syndrome with important epidemiological and clinical implications in older adults. One of the most accepted definitions of frailty is that of Fried and Walston, who operationalised it according to five well defined criteria. However, their criteria are not readily applicable in primary care, where practitioners need tools to identify patients who require priority access to more specialised resources. With that objective in mind, our research group published the Frailty Instrument of the Survey of Health, Ageing and Retirement in Europe (SHARE-FI). The present paper reports the results of the Spanish sample.

Methods

In the wave 1 of SHARE (2004), the Spanish sample was composed of 1,279 women and 933 men, all living in the community (mean age: 65.6 years). For each sex, a latent class analysis was used to summarise the five (adapted) frailty criteria into three incremental frailty classes. We tested the association of the frailty classes against a biopsychosocial range of wave 1 variables; the predictive validity of the frailty classes was tested using mortality data from the second wave of SHARE (2006-2007), which were available for 846 women and 660 men.

Results

The frailty classes had the expected cross-sectional associations. The age-adjusted Odds ratio for mortality (with 95% confidence interval) associated with the frail class was 3.2 (1.0-10.2) for women and 8.3 (3.1-22.1) for men.

Discussion

SHARE-FI is a valid and freely accessible instrument, which is intended to facilitate the adoption of the frailty paradigm in primary care.  相似文献   

17.

Objectives

Retrospective evaluation of the SPECT/CT role in the Sentinel Lymph Node identification.

Patients and methods

Thirty-two patients underwent a lymphoscintigraphy with SPECT/CT imaging. Those patients presented several cancer types (16 melanoma, one squamous cell carcinoma, three breast cancers, eight vulvar cancers, three cervical cancers).

Results

The scintigraphic detection rate was 81% with planar imaging while this rate was 89% with SPECT/CT. The SPECT/CT provided an additional quantitative information in 66% cases. Moreover, the quality of the interpretation was better in two different conditions (planar interpretation followed by routine and blinded SPECT/CT interpretation) with SPECT/CT. In our study, the false negative rate is 4.5%.

Conclusions

SPECT/CT provides quantitative and qualitative informations in the sentinel lymph node detection. Therefore, it can be a valuable tool for the surgeon to find and harvest the sentinel lymph node especially where the lymphatic drainage pattern can be unusual or hard to predict (cervical or trunk localisation). It's a new tool for preoperative detection and it can decrease the false negative rate.  相似文献   

18.
Alzheimer's disease (AD) is expected to affect more than 22 million people worldwide by 2025, causing devastating suffering and enormous costs to families and society. AD is a multifactorial disease, with a complex pathological mosaic. In rodents, AD-like dementia can be induced by cerebral microinjection of Aβ peptide, leading to amyloid deposits, amnesia and various features of neurodegeneration. Marapuama (Ptychopetalum olacoides) is regarded as a “brain tonic” in the Amazon region and shows a nootropic profile in rodents.

Aim of the study

Because a specific extract (POEE) of Marapuama was shown to possess promnesic and anti-amnesic properties, the aim of this study was to verify if POEE is also effective against Aβ1-42-induced cognitive deficit in mice. Additionally, Aβ deposits (Congo red), GFAP immunoreactivity (immunohistochemistry), and neurodegenerative changes in the hippocampal pyramidal layer (Nissl) were examined as measures of Aβ1-42-induced neurodegeneration.

Materials and methods

CF1 mice were subjected to the experimental Alzheimer model with the Aβ1-42 i.c.v. administration. The effects of POEE 800 mg/kg were evaluated over 14 consecutive days of treatment.

Results

The data show that 14 days of oral treatment with POEE (800 mg/kg) was effective in preventing Aβ-induced cognitive impairment, without altering the levels of BDNF and with parallel reductions in Aβ deposits and astrogliosis. CA1 hippocampus loss induced by Aβ1-42 was also diminished in POEE-treated mice.

Conclusion

This study offers evidence of functional and neuroprotective effects of two weeks treatment with a Ptychopetalum olacoides extract against Aβ peptide-induced neurotoxicity in mice. Given the multifactorial nature of neurodegeneration, the considerable potential for an AChE inhibitor displaying associated neuroprotective properties such as here reported warrants further clinic evaluation.  相似文献   

19.
Purine salvage pathways in the apicomplexan parasite Toxoplasma gondii   总被引:7,自引:0,他引:7  
We have exploited a variety of molecular genetic, biochemical, and genomic techniques to investigate the roles of purine salvage enzymes in the protozoan parasite Toxoplasma gondii. The ability to generate defined genetic knockouts and target transgenes to specific loci demonstrates that T. gondii uses two (and only two) pathways for purine salvage, defined by the enzymes hypoxanthine-xanthine-guanine phosphoribosyltransferase (HXGPRT) and adenosine kinase (AK). Both HXGPRT and AK are single-copy genes, and either one can be deleted, indicating that either one of these pathways is sufficient to meet parasite purine requirements. Fitness defects suggest both pathways are important for the parasite, however, and that the salvage of adenosine is more important than salvage of hypoxanthine and other purine nucleobases. HXGPRT and AK cannot be deleted simultaneously unless one of these enzymes is provided in trans, indicating that alternative routes of functionally significant purine salvage are lacking. Despite previous reports to the contrary, we found no evidence of adenine phosphoribosyltransferase (APRT) activity when parasites were propagated in APRT-deficient host cells, and no APRT ortholog is evident in the T. gondii genome. Expression of Leishmania donovani APRT in transgenic T. gondii parasites yielded low levels of activity but did not permit genetic deletion of both HXGPRT and AK. A detailed comparative genomic study of the purine salvage pathway in various apicomplexan species highlights important differences among these parasites.  相似文献   

20.

Background

The aim of this work was to evaluate the hepatoprotective ability of allopurinol to prevent the liver injury induced by carbon tetrachloride (CCl4).

Methods

Acute liver damage was induced with CCl4 (4 g/kg, by gavage); allopurinol (50 mg/kg, by gavage) was given 1 h before and 1 h after CCl4 intoxication and two daily doses for the previous three days. Cirrhosis was established by CCl4 administration (0.4 g/kg, i. p. three times a week, eight weeks); allopurinol was administered (100 mg/kg, by gavage, daily) during the long-term of CCl4 treatment. Alanine aminotransferase (ALT), γ-glutamyl transpeptidase (γ-GTP), xanthine oxidase (XO), lipid peroxidation, reduced and oxidized glutathione (GSH, GSSG, respectively), hydroxyproline and histopathologycal analysis were performed. Nuclear factor-κB (NF-κB), pro-inflammatory and anti-inflammatory cytokines, transforming growth factor-β (TGF-β) and metalloproteinase-13 (MMP-13) were analyzed by Western blots.

Results

Acute injury increased ALT and γ-GTP activities, additionally enhanced NF-κB nuclear translocation and cytokines production such as tumor necrosis factor-α, interleukine-1β, and interleukine-6. Allopurinol partially prevented these effects, while increased interleukine-10. Acute and chronic CCl4 treatments altered the levels of XO activity, lipid peroxidation, and GSH/GSSG ratio, while these remained within normal range with allopurinol administration. Necrosis, fibrosis and TGF-β production induced in chronic injury were partially prevented by allopurinol, interestingly, this drug induced MMP-13 activity.

Conclusions

Allopurinol possesses antioxidant, anti-inflammatory and antifibrotic properties, probably by its capacity to reduce NF-κB nuclear translocation and TGF-β expression, as well as to induce MMP-13.General significanceAllopurinol might be effective treatment of liver diseases.  相似文献   

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