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1.
Variations in enzyme activity in stomach and pancreatic tissue and digesta in piglets around weaning
A study was performed to investigate the effect of weaning at 4 weeks of age on the activity of digestive enzymes in the stomach and pancreatic tissue and in digesta from 3 days prior to weaning to 9 days postweaning in 64 piglets. In stomach tissue the activity of pepsin and gastric lipase was determined. Pepsin activity declined abruptly after weaning but 5 days postweaning the weaning level was regained and in the gastric contents no change in pepsin activity was observed. Weaning did not influence the activity of gastric lipase. The activity of eight enzymes and a cofactor was measured in pancreatic tissue. The effect of weaning on the enzyme activity was highly significant for all enzymes except elastase. The activity of all enzymes remained at the weaning level during day 1–2 postweaning followed by a reduction of the activity. The activity of trypsin, carboxypeptidase A, amylase and lipase exhibited minimum activity 5 days postweaning. Trypsin activity increased to the preweaning level on day 7–9 whereas the activity of the others increased but did not reach the preweaning level. The activity of chymotrypsin, carboxypeptidase B and carboxyl ester hydrolase decreased during the entire experimental period. In digesta no effect of weaning was observed on the activity of amylase and trypsin. The activity of chymotrypsin was reduced after weaning in the proximal third of the small intestine and lipase and carboxyl ester hydrolase activity was reduced in the middle and distal parts of the small intestine after weaning. The present study shows that the activities of the digestive enzymes in the pancreatic tissue are affected by weaning. Even though the pancreatic secretion cannot be judged from these results they show that the enzymes respond differently to weaning. In general the activity of the digestive enzymes in pancreatic tissue is low on day 5 postweaning which in interaction with other factors may increase the risk of developing postweaning diarrhoea. 相似文献
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Hillert L Akerstedt T Lowden A Wiholm C Kuster N Ebert S Boutry C Moffat SD Berg M Arnetz BB 《Bioelectromagnetics》2008,29(3):185-196
Findings from prior studies of possible health and physiological effects from mobile phone use have been inconsistent. Exposure periods in provocation studies have been rather short and personal characteristics of the participants poorly defined. We studied the effect of radiofrequency field (RF) on self-reported symptoms and detection of fields after a prolonged exposure time and with a well defined study group including subjects reporting symptoms attributed to mobile phone use. The design was a double blind, cross-over provocation study testing a 3-h long GSM handset exposure versus sham. The study group was 71 subjects age 18-45, including 38 subjects reporting headache or vertigo in relation to mobile phone use (symptom group) and 33 non-symptomatic subjects. Symptoms were scored on a 7-point Likert scale before, after 1(1/2) and 2(3/4) h of exposure. Subjects reported their belief of actual exposure status. The results showed that headache was more commonly reported after RF exposure than sham, mainly due to an increase in the non-symptom group. Neither group could detect RF exposure better than by chance. A belief that the RF exposure had been active was associated with skin symptoms. The higher prevalence of headache in the non-symptom group towards the end of RF exposure justifies further investigation of possible physiological correlates. The current study indicates a need to better characterize study participants in mobile phone exposure studies and differences between symptom and non-symptom groups. 相似文献
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The ITGAV rs3738919 variant and susceptibility to rheumatoid arthritis in four Caucasian sample sets
Jade E Hollis-Moffatt Kerry A Rowley Amanda J Phipps-Green Marilyn E Merriman Nicola Dalbeth Peter Gow Andrew A Harrison John Highton Peter BB Jones Lisa K Stamp Pille Harrison B Paul Wordsworth Tony R Merriman 《Arthritis research & therapy》2009,11(5):R152
Introduction
Angiogenesis is an important process in the development of destructive synovial pannus in rheumatoid arthritis (RA). The ITGAV +gene encodes a cell cycle-associated antigen, integrin ανβ 3, which plays a role in RA angiogenesis. Previously, two independent studies identified an association between the major allele of the ITGAV single-nucleotide polymorphism (SNP) rs3738919 and RA. We therefore tested this association in an independent study using New Zealand (NZ) and Oxford (UK) RA case control samples.Methods
We compared genotype frequencies in 740 NZ Caucasian RA patients and 553 controls genotyped for rs3738919, using a polymerase chain reaction-restriction fragment length polymorphism assay. A TaqMan genotyping SNP assay was used to type 713 Caucasian RA patients and 515 control samples from Oxford for the rs3738919 variant. Association of rs3738919 with RA was tested in these two sample sets using the chi-square goodness-of-fit test. The Mantel-Haenszel test was used to perform a meta-analysis, combining the genetic results from four independent Caucasian case control cohorts, consisting of 3,527 cases and 4,126 controls. Haplotype analysis was also performed using SNPs rs3911238, rs10174098 and rs3738919 in the Wellcome Trust Case Control Consortium, NZ and Oxford case control samples.Results
We found no evidence for association between ITGAV and RA in either the NZ or Oxford sample set (odds ratio [OR] = 0.88, Pallelic = 0.11 and OR = 1.18, Pallelic = 0.07, respectively). Inclusion of these data in a meta-analysis (random effects) of four independent cohorts (3,527 cases and 4,126 controls) weakens support for the hypothesis that rs3738919 plays a role in the development of RA (ORcombined = 0.92, 95% confidence interval 0.80 to 1.07; P = 0.29). No consistent haplotype associations were evident.Conclusions
Association of ITGAV SNP rs7378919 with RA was not replicated in NZ or Oxford case control sample sets. Meta-analysis of these and previously published data lends limited support for a role for the ITGAV in RA in Caucasians of European ancestry. 相似文献5.
The aim with the present study was to assess possible age-related differences in the serum prolactin, cortisol and blood glucose responses to standardized surgical stress in humans. Relatively healthy men suffering from inguinal hernias were selected. The subjects were divided into a group of younger people (M=36.4 years, r=13–45, n=7) and one of older people (M=66.5 years, r=56–75, n=9). Surgery was carried out under general anesthesia. Blood was drawn before, during and following the operation. Blood pressure and pulse rate were also monitored. No differences were noticed in plasma prolactin, cortisol, and blood glucose during basal conditions. Even though plasma prolactin increased significantly in both groups during surgery, it was higher in the younger group (M= 56.2 μg/1) as compared with 28.7 μg/1 for the older group, p<.01. Plasma prolactin during surgery, but not under basal conditions, correlated inversely with age. No differences between groups were found during surgery in blood glucose and serum cortisol. This study indicates a diminished stress response in older subjects, possibly due to age-related neuroendocrine changes. 相似文献
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JB Parentes-Vieira PV Lopes-Costa CG Pires AR dos Santos JD Pereira-Filho BB da Silva 《International Seminars in Surgical Oncology : ISSO》2007,4(1):22
Background
The objective of this study was to evaluate angiogenesis according to CD34 antigen expression in estrogen receptor (ER)-positive and negative breast carcinomas.Methods
This study comprised 64 cases of infiltrating ductal carcinoma in postmenopausal women divided into two groups: Group A: ER-positive, n = 35; and Group B: ER-negative, n = 29. The anti-CD34 monoclonal antibody was used as a marker for endothelial cells. Microvessel count was carried out in 10 fields per slide using a 40× objective lens (magnification 400×). Statistical analysis of the data was performed using Student's t-test (p < 0.05).Results
The mean number of vessels stained with the anti-CD34 antibody in the estrogen receptor-positive and negative tumors was 23.51 ± 1.15 and 40.24 ± 0.42, respectively. The number of microvessels was significantly greater in the estrogen receptor-negative tumors (p < 0.001).Conclusion
ER-negative tumors have significantly greater CD34 antigen expression compared to ER-positive tumors.7.
Wiholm C Lowden A Kuster N Hillert L Arnetz BB Akerstedt T Moffat SD 《Bioelectromagnetics》2009,30(1):59-65
Radiofrequency (RF) emission during mobile phone use has been suggested to impair cognitive functions, that is, working memory. This study investigated the effects of a 2 1/2 h RF exposure (884 MHz) on spatial memory and learning, using a double-blind repeated measures design. The exposure was designed to mimic that experienced during a real-life mobile phone conversation. The design maximized the exposure to the left hemisphere. The average exposure was peak spatial specific absorption rate (psSAR10g) of 1.4 W/kg. The primary outcome measure was a "virtual" spatial navigation task modeled after the commonly used and validated Morris Water Maze. The distance traveled on each trial and the amount of improvement across trials (i.e., learning) were used as dependent variables. The participants were daily mobile phone users, with and without symptoms attributed to regular mobile phone use. Results revealed a main effect of RF exposure and a significant RF exposure by group effect on distance traveled during the trials. The symptomatic group improved their performance during RF exposure while there was no such effect in the non-symptomatic group. Until this new finding is further investigated, we can only speculate about the cause. 相似文献
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We have previously reported that human subjects undergoing surgery for inguinal hernias exhibit an age-related attenuation in the plasma prolactin response, with no differences during resting conditions. We suggested that these differences were due to age-related neuroendocrine changes, but that peripheral factors may play a role as well. In the present study, we have assessed the pituitary response to 500 micrograms of thyrotropin-releasing hormone (TRH) in the very same subjects previously studied during surgery. Blood samples were drawn immediately prior to, as well as 10, 20, 40 and 60 minutes following the intravenous administration of TRH. There was a clear-cut age-related attenuation in the pituitary prolactin response with no difference in the thyrotropin (TSH) response. Maximum prolactin response in the young subjects was 31.7 micrograms/l and 19.2 micrograms/l in old subjects (F(4) = 3.5, p less than .01, two-way ANOVA). These results indicate that the age-related differences in the prolactin response to stress are mainly due to pituitary changes. However, prolactin-secreting cells are under the control of the hypothalamus. Therefore, the possibility must be considered that aging or other concurrent factors could be exerting their influence via the hypothalamus and not necessarily directly at the pituitary level. 相似文献
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Glauber P Arêas R?de BB Schuab Felipe PG Neves Rosana R Barros 《Memórias do Instituto Oswaldo Cruz》2014,109(7):935-939
Streptococcus pyogenes is responsible for a variety of infectious
diseases and immunological complications. In this study, 91 isolates of S.
pyogenes recovered from oropharynx secretions were submitted to
antimicrobial susceptibility testing, emm typing and pulsed-field
gel electrophoresis (PFGE) analysis. All isolates were susceptible to ceftriaxone,
levofloxacin, penicillin G and vancomycin. Resistance to erythromycin and clindamycin
was 15.4%, which is higher than previous reports from this area, while 20.9% of the
isolates were not susceptible to tetracycline. The macrolide resistance phenotypes
were cMLSB (10) and iMLSB (4). The ermB gene was predominant,
followed by the ermA gene. Thirty-two emm types and
subtypes were found, but five (emm1, emm4,
emm12, emm22, emm81) were detected in
48% of the isolates. Three new emm subtypes were identified
(emm1.74, emm58.14, emm76.7).
There was a strong association between emm type and PFGE clustering.
A variety of PFGE profiles as well as emm types were found among
tetracycline and erythromycin-resistant isolates, demonstrating that antimicrobial
resistant strains do not result from the expansion of one or a few clones. This study
provides epidemiological data that contribute to the development of suitable
strategies for the prevention and treatment of such infections in a poorly studied
area. 相似文献
10.
Jade E Hollis-Moffatt Michael Chen-Xu Ruth Topless Nicola Dalbeth Peter J Gow Andrew A Harrison John Highton Peter BB Jones Michael Nissen Malcolm D Smith Andre van Rij Gregory T Jones Lisa K Stamp Tony R Merriman 《Arthritis research & therapy》2010,12(3):1-11