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1.
This study examined functional properties and biocompatibility of glutaraldehyde-fixed bovine articular cartilage over several weeks of incubation at body temperature to investigate its potential use as a resurfacing material in joint arthroplasty. In the first experiment, treated cartilage disks were fixed using 0.02, 0.20 and 0.60% glutaraldehyde for 24 h then incubated, along with an untreated control group, in saline for up to 28 d at 37 °C. Both the equilibrium compressive and tensile moduli increased nearly twofold in treated samples compared to day 0 control, and remained at that level from day 1 to 28; the equilibrium friction coefficient against glass rose nearly twofold immediately after fixation (day 1) but returned to control values after day 7. Live explants co-cultured with fixed explants showed no quantitative difference in cell viability over 28 d. In general, no significant differences were observed between 0.20 and 0.60% groups, so 0.20% was deemed sufficient for complete fixation. In the second experiment, cartilage-on-cartilage frictional measurements were performed under a migrating contact configuration. In the treated group, one explant was fixed using 0.20% glutaraldehyde while the apposing explant was left untreated; in the control group both explants were left untreated. From day 1 to 28, the treated group exhibited either no significant difference or slightly lower friction coefficient than the untreated group. These results suggest that a properly titrated glutaraldehyde treatment can reproduce the desired functional properties of native articular cartilage and maintain these properties for at least 28 d at body temperature.  相似文献   

2.
Gut microbial colonization and immune response may be affected by milk feeding method. The objective of this study was to determine the effects of feeding high or low volumes of milk on fecal bacterial count, inflammatory response, blood metabolites and growth performance of Holstein female calves. Colostrum-fed calves (n = 48) were randomly assigned to either high milk (HM; n = 24) or low milk (LM; n = 24) feeding groups. Low milk-fed calves were fed pasteurized whole milk at 10% of BW until weaning. In HM group, milk was offered to calves at 20% of BW for the first 3 weeks of life. Then, milk allowance was decreased gradually to reach 10% of BW on day 26 and remained constant until weaning on day 51. Calves were allowed free access to water and starter throughout the experiment. Body weight was measured weekly, and blood samples were taken on days 14, 28 and 57. Fecal samples were collected on days 7, 14 and 21 of age for the measurement of selected microbial species. By design, HM calves consumed more nutrients from milk during the first 3 weeks and they were heavier than LM calves on days 21, 56 and 98. High milk-fed calves had greater serum glucose and triglyceride levels on day 14 with no significant difference between groups on days 28 and 57. Blood urea nitrogen was higher in LM calves on day 14, but it was lower in HM calves on day 28. Calves in LM group had significantly greater blood tumor necrosis factor-α (TNF-α) than HM calves throughout the experiment. Serum amyloid A (SAA) concentration was higher in LM calves on day 14. However, HM calves showed higher levels of SAA at the time of weaning. Feeding high volumes of milk resulted in lower serum cortisol levels on days 14 and 28 but not at the time of weaning in HM calves compared to LM counterparts. Lactobacillus count was higher in feces sample of HM calves. Conversely, the numbers of Escherichia coli was greater in the feces of LM calves. Calves in HM group showed fewer days with fever and tended to have fewer days treated compared to LM group. In conclusion, feeding higher amounts of milk during the first 3 weeks of life improved gut microbiota, inflammation and health status and growth performance of Holstein dairy calves.  相似文献   

3.
The aim of this study was to investigate stem cell factor and c-kit gene expression and protein localization in the mesonephros and ovary of sheep fetuses at different days of gestation, using RNA in situ hybridization and immunohistochemical procedures. At days 24 and 26 of gestation, stem cell factor mRNA and protein were present in cells throughout the developing gonad and mesonephros. From day 28 to day 40 of gestation, stem cell factor mRNA and protein became increasingly localized to the cortical region of the ovary, where most germ cells were present as actively proliferating oogonia. From day 40 to day 90 of gestation, stem cell factor mRNA and protein localization were confined mainly to the ovarian cortex. Moreover, within the cortical region, stem cell factor mRNA was low or absent where follicles were first forming and highest in the outer ovarian cortex, where germ cells were undergoing mitosis or the early stages of meiosis. In contrast, stem cell factor protein was present in newly forming follicles, as well as in mitotic and meiotic germ cells, which is consistent with the presence of both membrane-bound and soluble forms of this ligand. However, by day 90 of gestation, both stem cell factor mRNA and protein were observed in the granulosa cells of most (> 90%) primordial follicles. C-kit mRNA and protein were observed from day 24 of gestation in both germ cells and somatic cells but, with increasing gestational age, preferentially in germ cells (for example, pre-meiotic germ cells and both isolated oocytes and follicle-enclosed oocytes). C-kit protein, but not mRNA, was also observed in germ cells that were undergoing meiosis. The results indicate that the cells containing stem cell factor mRNA within the ovary up to day 90 of gestation originated from the gonadal blastema and from cells that migrated from the mesonephros before day 28 of gestation. Since stem cell factor mRNA was absent in both mesonephric cells migrating after day 28 of gestation and in regions where follicles were first forming, it is suggested that these later migrating mesonephric cells are the progenitors of the granulosa cells in the first forming follicles. In conclusion, during follicle formation, c-kit mRNA is localized to germ cells whereas c-kit, together with stem cell factor protein, is localized to both germ cells and somatic cells, consistent with the hypothesis that the presence of this receptor-ligand pair is essential to prevent apoptosis.  相似文献   

4.
Revefenacin is a once-daily long-acting muscarinic antagonist (LAMA) in clinical development for the treatment of patients with chronic obstructive pulmonary disease (COPD). In a dose-ranging study, nebulized once-daily revefenacin had a long duration of action in patients after 7 days’ administration of doses up to 700 μg. In this multiple-dose study, the bronchodilation efficacy and adverse events profile were characterized in patients administered nebulized revefenacin once daily for 28 days. A total of 355 COPD patients (mean age 62 years, mean forced expiratory volume in 1 s [FEV1] 44% of predicted) were randomized in a double-blind, placebo-controlled parallel group study. Inhaled corticosteroids as well as short-acting bronchodilators were permitted. Once-daily treatments (44, 88, 175 or 350 μg revefenacin or matching placebo) were administered by a standard jet nebulizer, for 28 days. The primary endpoint was change from baseline in D28 trough FEV1, and secondary endpoints included weighted mean FEV1 over 0 to 24 h and rescue medication (albuterol) use. Safety evaluations included adverse events, laboratory assessments, electrocardiograms and 24-h Holter profiles. Revefenacin (88, 175 and 350 μg) significantly improved D28 trough FEV1 over placebo (187.4, 166.6 and 170.6 mL, respectively, all p < 0.001); 44 μg produced a sub-therapeutic response. At doses ≥88 μg, more than 80% of patients achieved at least a 100-mL increase from baseline FEV1 in the first 4 h post dose compared with 33% of placebo patients. For doses ≥88 μg, D28 24 h weighted mean differences from placebo for FEV1 were numerically similar to respective trough FEV1 values, indicating bronchodilation was sustained for 24 h post dose. Doses ≥88 μg reduced the average number of albuterol puffs/day by more than one puff/day. The 350 μg dose did not demonstrate additional efficacy over that observed with 175 μg revefenacin. Revefenacin was generally well tolerated, with minimal reports of systemic anti-cholinergic effects. These data suggest that 88 and 175 μg revefenacin are appropriate doses for use in longer-term safety and efficacy trials. Revefenacin offers the potential for the first once-daily LAMA for nebulization in patients with COPD who require or prefer a nebulized drug delivery option. ClinicalTrials.gov NCT02040792 . Registered January 16, 2014.  相似文献   

5.
This study was conducted to determine the efficacy of feeding melengestrol acetate (MGA) for 14 days and administering prostaglandin F(2)alpha (PGF) 17 days after MGA to synchronize or induce estrus in yearling beef heifers. The study involved 56 Angus (n = 19), Hereford (n = 15) and Simmental (n = 22) heifers that were assigned by breed and pubertal status to either MGA+PGF or to control groups. Heifers in the synchronized group were fed 0.5 mg MGA per head per day for 14 days from a grain carrier and were injected with 25 mg, i.m. PGF 17 days after the last daily feeding of MGA. Control heifers were fed from a grain carrier without MGA and were not treated with PGF. Heifers were classified as pubertal when concentrations of progesterono in the serum exceeded 1 ng/ml in 1 of 2 samples collected prior to the initiation of treatments. Blood samples were collected 7 days before and on the day that treatment with MGA or carrier began and 7 days before and on the day that PGF was administered. Progesterone concentrations in the serum were elevated ( > 1 ng/ml) in 61% (17 28 ) of the MGA+PGF-treated heifers and in 61% (17 28 ) of the control heifers prior to feeding MGA. However, concentrations of progesterone in the serum at the time PGF was administered differed (P<0.05) between MGA+PGF and control groups. Concentrations of progesterone in the serum exceeded 1 ng/ml in 100% (28 28 ) of the MGA+PGF-treated heifers and in 71% (20 28 ) of control heifers at the time PGF was administered (P<0.05). All heifers were inseminated 12 hours after the first detected estrus. Twenty-two of 28 (79%) of the MGA+PGF-treated heifers exhibited estrus within 6 days after PGF compared with 9 of 28 (32%) of control heifers (P<0.05). The conception rate at first service did not differ between MGA+PGF and control groups (64% and 67%, respectively). Synchronized pregnancy rates were higher (P<0.05) for MGA+PGF-treated heifers than for control heifers (14 28 , 50% vs 6 28 , 21%). Increased concentrations of progesterone in serum at the time PGF was administered and higher pregnancy rates during the synchronized period among MGA+PGF-treated heifers demonstrate the efficacy of this treatment for use in estrus synchronization. Moreover, this treatment may have a potential effect on inducing puberty in breeding age heifers.  相似文献   

6.
In healthy male top athletes several functions were measured after either a westbound flight over six time-zones (WEST: Frankfurt–Atlanta; n=13) or an eastbound flight over eight time-zones (EAST: Munich–Osaka; n=6). Under either condition the athletes performed two standardized exercise training units in the morning and in the afternoon within 24 h, investigations were done as controls in Germany and on day 1, 4, 6, and 11, after arrival. The primary aim of the study was to evaluate the effect of time-zone transitions on the 24h profiles of blood pressure (BP) and heart rate (HR) using an ambulatory BP device (SpaceLabs 90207), for up to 11 d after arrival at the destination. As additional parameters, we studied jet-lag symptoms, training performance, and training coordination by using visual analog scales. Finally, oral temperature and grip strength were measured, and saliva samples were analyzed for cortisol and melatonin. The study showed that all functions were disturbed on the first day after arrival at the destination, jet-lag symptoms remained until day 5–6 after WEST and day 7 after EAST, training performance was worst within the first 4 d after WEST. In accordance with earlier reports, cortisol, melatonin, body temperature, and grip strength were affected in their 24h profiles and additionally modified by the training units. Surprisingly, BP and HR were not only affected on the first day but also the time-zone transition led to an increase in BP after WEST and a decrease in BP after EAST. However, the training units seemed to influence the BP profile more than the time-zone transitions. HR rhythm was affected by both time-zone transitions and exercise. It is concluded that not only jet-lag symptoms but also alterations in physiological functions should be considered to occur in highly competitive athletes due to time-zone transition and, therefore, an appropriate time of reentrainment is recommended.  相似文献   

7.
In healthy male top athletes several functions were measured after either a westbound flight over six time-zones (WEST: Frankfurt-Atlanta; n=13) or an eastbound flight over eight time-zones (EAST: Munich-Osaka; n=6). Under either condition the athletes performed two standardized exercise training units in the morning and in the afternoon within 24 h, investigations were done as controls in Germany and on day 1, 4, 6, and 11, after arrival. The primary aim of the study was to evaluate the effect of time-zone transitions on the 24h profiles of blood pressure (BP) and heart rate (HR) using an ambulatory BP device (SpaceLabs 90207), for up to 11 d after arrival at the destination. As additional parameters, we studied jet-lag symptoms, training performance, and training coordination by using visual analog scales. Finally, oral temperature and grip strength were measured, and saliva samples were analyzed for cortisol and melatonin. The study showed that all functions were disturbed on the first day after arrival at the destination, jet-lag symptoms remained until day 5-6 after WEST and day 7 after EAST, training performance was worst within the first 4 d after WEST. In accordance with earlier reports, cortisol, melatonin, body temperature, and grip strength were affected in their 24h profiles and additionally modified by the training units. Surprisingly, BP and HR were not only affected on the first day but also the time-zone transition led to an increase in BP after WEST and a decrease in BP after EAST. However, the training units seemed to influence the BP profile more than the time-zone transitions. HR rhythm was affected by both time-zone transitions and exercise. It is concluded that not only jet-lag symptoms but also alterations in physiological functions should be considered to occur in highly competitive athletes due to time-zone transition and, therefore, an appropriate time of reentrainment is recommended.  相似文献   

8.
The effect of germination temperature, duration of high-intensitylight, and day temperature in modifying the influence of nighttemperature on the flowering process of the M-8 strain of Uplandcotton was examined. In general, night temperatures above 28°C caused the first floral branch to be formed at a higher node.The magnitude of the reaction was conditioned by the other environmentalfactors studied. Germination temperature had a slight but significanteffect on subsequent floral responses to night temperature.Plants given eight-hour periods of high-intensity light eachday were delayed more by high night temperature than those exposedto 14 or 24 hours of high light. At high day temperatures (28–32°C) the inhibiting influence of the high night temperature wasgreatly increased. High day temperatures delayed floral initiationif the night temperature was high (28–32°C) but causeda lowering of position of first floral branch when the nighttemperature was low (20–22°C). The enhancement offlowering by 32°C days and 22°C nights was expressednot only in the low node of first floral branch, but also inthe shorter time from planting to floral initiation.  相似文献   

9.
Sexually mature domestic cats were hormonally stimulated to induce superovulation; embryo recovery was accomplished by laparotomy. Embryos were frozen by conventional embryo freezing methods used in the domestic cattle embryo transfer industry. Thawing was achieved in a 28 degrees C or 37 degrees C waterbath or in ambient air. Overnight culture of the frozen-thawed embryos in a supplemented Nutrient Mixture F-10 (Ham's) or Earle's Balanced Salt Solution with 20% heat-treated newborn calf serum resulted in five successful term litters from recipient queens. Embryo recipients who became pregnant had been treated with a subcutaneous injection of follicle-stimulating hormone (FSH-P) once every 24 hr for 6 days in the amount of 0.2 mg/day for the first 5 days and 0.1 mg on the sixth day, followed by two intramuscular 750 IU injections of human chorionic gonadotropin 24 hr apart, beginning on the same day as the sixth injection of FSH-P.  相似文献   

10.
Task-switching between foraging and building in workers of Nasutitermes exitiosus (Termitidae), a subterranean termite, was followed using mark-recapture. Foragers were collected from wood-filled drums and marked with Nile blue (ca. 12,500 per colony), whereas builders were collected from damaged sections of mounds and marked with Neutral red (ca. 18,500 per colony). Two protocols were followed: the first marked foragers and then damaged the mound; the second reversed this order. In the first protocol few foragers switched to building, i.e. blue-marked workers in mound samples, measured either as numbers (81 ± 28) or proportion of originally marked (0.66 ± 0.20 %); whereas more than double blue-marked foragers remained foraging (222 ± 64 workers or 1.76 ± 0.44 %). In the second protocol few builders had switched to foraging, i.e. red-marked workers found in the first drum sample (82 ± 33 workers or 0.29 ± 0.09 %). Up to eight drums were sampled for foragers over about 80 days; the numbers of blue-marked workers decreased slowly (ca. 1.6 workers per day) whereas those of red-marked workers increased slowly (ca. 2.4 workers per day). These results suggest that relatively few termite workers switch directly between foraging and building. The possibility of builders being recruited from other tasks is discussed. Received 24 March 2005; revised 27 June 2005; accepted 2 July 2005.  相似文献   

11.
The aim of this study was to establish baseline ultrasound data concerning the mule conceptus during gestation. Ten multiparous Trotter mares were artificially inseminated with chilled semen from an Amiatino jack donkey. Daily transrectal ultrasonography was carried out from the day of ovulation until Day 50 of gestation to determine the following: first detection of the embryonic vesicle (EV), mobility phase, EV diameter, day of EV fixation, changes in EV shape, date of yolk sac regression and embryo crown-rump length. Monthly ultrasonic assessments from Day 50 of gestation to term were carried out. These assessments included an evaluation of fetal well-being and the growth of the mule conceptus, which were monitored using the following variables: cardiac activity, fetal activity and presentation, fetal fluid echogenicity, combined thickness of the utero-placenta unit and fetal orbital and aortic diameter. Mule EV first detection was observed earlier (37% at Day 8) than that observed in the equine pregnancy. EV diameter at first detection was 4.6 ± 1.1 mm. At Day 10, 75% of EVs were detected. EV fixation occurred on Day 17.1 ± 1.1, with a mean EV diameter of 2.5 ± 0.2 cm. EV growth rate was 4.04 mm/day from Days 11 to 16, 0.4 mm/day from Days 16 to 28 and 1.78 mm/day from Days 28 to 45 of pregnancy. The embryo proper was first detected on Day 19.9 ± 1.9 (average length 2.4 ± 1.4 mm), and the embryonic heartbeat was first detected on Day 24 ± 2.4. The fetal carotid pulse was observed at six months of gestation and provided a good means by which to estimate fetal cardiac activity in advanced gestation. The fetal heart rate was recorded from Month 2 of gestation to term. The mean ± SD of the combined uteroplacental thickness was assessed at the cervical-placental junction and at the ventral abdomen in mares between Months 2 and 5 until term, respectively. An abnormal fetal-placental unit and fetal inactivity was observed in association with abortion. Mule-conceptus biometric measurements correlated significantly with the gestational age, and these data were used to predict an unusually large mule fetus, which might result in dystocia. In conclusion, we can assume that early diagnosis of pregnancy failure and assessment of fetal biophysical profile and growth charts could improve the chances of gestation completion in mule-pregnant mares. The early detection of mares at risk for an abnormal pregnancy or delivery may increase the success of prompt treatments, therefore preventing costly emergency procedures and allowing proper obstetrical and neonatal assistance.  相似文献   

12.
Normal embryonic development depends on the maintenance of a population of normal healthy cells within each embryo. The aim of this study was to use a combination of apoptotic measures to assess differences in embryo quality after IVF with semen samples with high percentages of abnormal spermatozoa. Semen samples were obtained and cryopreserved from four Holstein bulls before (5 day prior) and after (2 week-post-insult; 2 week-PI and day 20; 3 week-PI) a scrotal insulation period of 48 h (day 0). The swim-up sperm separation method was used. The post-thaw morphology revealed a decrease (P < 0.01) in the percentages of normal spermatozoa in the 3 week-PI samples in comparison with the pre-insult samples for Bulls I and III (74-22.3 and 67.7-0.5%, respectively). The percentage of vacuolated spermatozoa increased significantly for Bull II. After 18 h of sperm-oocyte co-incubation, zygotes were cultured and subpopulations were removed from culture at day 8 and subjected to either the TUNEL or caspase assay. On day 8, caspase intensity increased significantly for both Bull I (217+/-147) and Bull III (229+/-98) for the 3 week-PI embryo groups compared to the equivalent embryo groups for Bull II (98+/-115) and Bull IV (90+/-111). In conclusion, the inability to consistently measure apoptosis with TUNEL alone complicated the assessment of differences in embryo quality. Thus, it is uncertain exactly when during early pre-implantation development the differences in embryo quality are first manifest. Despite discrepancies, our results clearly indicated a difference in the embryo quality between embryos obtained after IVF with semen samples from bulls that had an intense response to scrotal insulation.  相似文献   

13.
The aim of the study was to analyze the kinetics of short-term changes in bone turnover. We studied in a randomized crossover design the effects of 6 days of bed rest on eight healthy male subjects (mean body wt: 70.1 +/- 5.7 kg; mean age: 25.5 +/- 2.9 yr). The metabolic ward period was divided into three parts: 4 ambulatory days, 6 days of either bed rest or non-bed rest periods, and 1 recovery day. The diet was identical in both bed rest and non-bed rest phases. Continuous urine collection started on the first day in the metabolic ward to analyze excretion of bone resorption markers, namely C-telopeptide (CTX) and N-telopeptide (NTX), creatinine, urea, and 3-methylhistidine. On the second ambulatory day and on the fifth day of bed rest or during the non-bed rest phase, blood was drawn to analyze bone formation markers and amino acid concentrations. Urinary calcium excretion was increased as early as the first day of bed rest (P < 0.01). CTX and NTX excretion stayed unchanged during the first 24 h of bed rest compared with the non-bed rest period. However, already on the second day, both resorption markers had increased significantly. NTX excretion increased by 28.7 +/- 14.0% (P < 0.01), whereas CTX excretion rose by 17.8 +/- 8.3% (P < 0.001). Creatinine, urea, and 3-methylhistidine excretion did not change. We conclude that 24 h of bed rest are sufficient to induce a significant rise in osteoclast activity in healthy subjects.  相似文献   

14.
After 16 h nocturnal deprivation of food, male Wistar rats were irradiated by a single whole body dose of 2.40 Gy X-rays. Both the irradiated and sham-irradiated (control) rats were pair-fed for the first six days after irradiation, but for the rest of the time they were fed ad libitum. Lipoprotein lipase activity (LPLA) in the adipose tissue fell between 24 and 48 h; LPLA in the heart fell at 24 h and 21 days and rose on the 14th days. The serum triacylglycerol concentration rose between 24 and 72 h. Comparison with the fed control group showed LPLA in adipose tissue to be reduced at 6 and 72 h and on the 28th day and raised between the 7th and the 14th day. In the heart it was raised at 1 h and between 72 h and the 14th day, it was reduced on the 21st day and rose on the 35th day. The triacylglycerol concentration was raised between 48 and 72 h and on the 28th day. Pair-feeding after non-lethal X-irradiation allowed more exact differentiation of the specific effect of ionizing radiation on LPLA in the adipose tissue and heart at the early post-irradiation intervals.  相似文献   

15.
The aim of the current study was to describe the use of a pool of different antisera raised against pregnancy-associated glycoproteins (PAGs; purified from both ovine and caprine placentas) for early pregnancy diagnosis in ovine species. Sixty-three pluriparous Sarda ewes (Ovis aries) were synchronized. Blood samples were withdrawn on Days 18, 24, 26, 28, 30, and 50 after mating. These samples were assayed for progesterone (radioimmunoassay [RIA] including an extraction step) and for pregnancy-associated glycoproteins (RIA-706 and RIA-srPool). Progesterone concentrations were under 1.0 ng/mL in all nonpregnant Sarda ewes. In pregnant ewes, mean progesterone concentrations ranged from 2.4 ng/mL (Day 24, single pregnancies) to 4.4 ng/mL (Day 28, multiple pregnancies). During all periods of examination, PAGs remained lower than 0.8 ng/mL in nonpregnant ewes. On Day 18 of pregnancy, PAG concentrations could be detected in 26 of 43 (60.5%) and in 41 of 43 (95.3%) pregnant ewes using the RIA-706 and RIA-srPool methods, respectively. From Day 24 to Day 50, using both RIA methods, PAGs could be detected in all pregnant ewes. On Day 24, the best threshold for pregnancy diagnosis was obtained by use of RIA-srPool, maximal concentration in nonpregnant ewes being 0.3 ng/mL and minimal concentration in pregnant ewes being 4.8 ng/mL. In general, progesterone and PAG concentrations were higher in multiple pregnancies than in single pregnancies. However, because of large individual variations, single pregnancies could not be differentiated from multiple pregnancies.  相似文献   

16.
It has been demonstrated that the number and differentiating potential of bone marrow mesenchymal stem cells (MSCs) decrease with age. Therefore, the search for alternative sources of MSCs is of significant value. In the present study, MSCs were isolated from umbilical cord blood (UCB) by combining gradient density centrifugation with plastic adherence. Cultured cells were treated with ascorbate acid-2-phosphate, dexamethasone, beta-glycerophosphate dexamethasone, insulin, 1-methyl-3-isobutylxamthine, indomethacin, beta-mercaptoethanol, butylated hydroxyanisole, FGF-4 and HGF. Differentiating characterization of UCB-derived MSCs were detected by cytochemistry, immunocytochemistry, radioimmunoassay, RT-PCR and urea assay. The results showed UCB-derived MSCs could differentiate into osteoblasts, adipocytes and neuron-like cells. When MSCs were cultured with FGF-4 and HGF, approximately 63.6% of cells became small, round and epithelioid on day 28 by morphology. Compared with the control, levels of AFP in the supernatant liquid increased significantly from day 12 and were higher on day 28 (P<0.01). Albumin increased significantly from day 16 (P<0.01). Urea was first detected on day 20 (P<0.01), and continued to increase on day 28 (P<0.01). Cells first expressed CK-18 on day 16 through immunocytochemistry analysis. RT-PCR analysis showed that differentiated cells could express a number of hepatocyte-specific genes in a time-dependent manner. Glycogen storage was first seen on day 24. Our results suggest that UCB-derived MSCs can differentiate not only into osteoblasts, adipocytes and neuron-like cells, but also into hepatocytes. Human UCB-derived MSCs are a new source of cell types for cell transplantation and therapy.  相似文献   

17.

Rationale

Bronchopulmonary dysplasia is one of the most serious complications observed in premature infants. Thanks to microarray technique, expression of nearly all human genes can be reliably evaluated.

Objective

To compare whole genome expression in the first month of life in groups of infants with and without bronchopulmonary dysplasia.

Methods

111 newborns were included in the study. The mean birth weight was 1029g (SD:290), and the mean gestational age was 27.8 weeks (SD:2.5). Blood samples were drawn from the study participants on the 5th, 14th and 28th day of life. The mRNA samples were evaluated for gene expression with the use of GeneChip® Human Gene 1.0 ST microarrays. The infants were divided into two groups: bronchopulmonary dysplasia (n=68) and control (n=43).

Results

Overall 2086 genes were differentially expressed on the day 5, only 324 on the day 14 and 3498 on the day 28. Based on pathway enrichment analysis we found that the cell cycle pathway was up-regulated in the bronchopulmonary dysplasia group. The activation of this pathway does not seem to be related with the maturity of the infant. Four pathways related to inflammatory response were continuously on the 5th, 14th and 28th day of life down-regulated in the bronchopulmonary dysplasia group. However, the expression of genes depended on both factors: immaturity and disease severity. The most significantly down-regulated pathway was the T cell receptor signaling pathway.

Conclusion

The results of the whole genome expression study revealed alteration of the expression of nearly 10% of the genome in bronchopulmonary dysplasia patients.  相似文献   

18.

Background  

Assessing RNA quality is essential for gene expression analysis, as the inclusion of degraded samples may influence the interpretation of expression levels in relation to biological and/or clinical parameters. RNA quality can be analyzed by agarose gel electrophoresis, UV spectrophotometer, or microcapillary electrophoresis traces, and can furthermore be evaluated using different methods. No generally accepted recommendations exist for which technique or evaluation method is the best choice. The aim of the present study was to use microcapillary electrophoresis traces from the Bioanalyzer to compare three methods for evaluating RNA quality in 24 fresh frozen invasive breast cancer tissues: 1) Manual method = subjective evaluation of the electropherogram, 2) Ratio Method = the ratio between the 28S and 18S peaks, and 3) RNA integrity number (RIN) method = objective evaluation of the electropherogram. The results were also related to gene expression profiling analyses using 27K oligonucleotide microarrays, unsupervised hierarchical clustering analysis and ontological mapping.  相似文献   

19.
The effects of one intraperitoneal injection of 60–65 mg/kg of 3-acetylpyridine (3-AP) on the levels of aspartate, glutamate, GABA, taurine, glycine, and alanine in the cerebellum, medulla, telencephalon, and diencephalon-mesencephalon of the rat were studied at various times (4–28 days) after injection. In the first 4–7 days, the levels of glutamate, GABA, glycine, and alanine in the cerebellum were 10–30% higher in the 3-AP-treated rats than in the control animals. By day 14, the levels of these four amino acids were normal (in the case of glutamate and glycine) or below normal (for GABA and alanine). By day 21, the values for GABA and alanine returned to normal. In the first 7 days, the level of aspartate in the cerebellum was the same in both the 3-AP- and saline-injected groups. From days 14 to 28, the level of aspartate in the cerebellum was 10–20% lower in the 3-AP-injected group than in the saline-treated animals. The level of taurine in the cerebellum was 15–30% lower in the 3-AP group than in the control group from days 7 to 28. The pattern of changes observed in the medulla in the first 7 days was similar to that found in the cerebellum for this period. However, unlike the data for the cerebellum, the level of aspartate in the medulla was unchanged by the 3-AP injection from day 14 to day 28, and the level of glutamate in the medulla remained higher (10–15%) from days 14 to 28 in the 3-AP-injected animals with respect to control values. The levels of taurine in the medulla were lower (10–15%) from day 7 to day 28 in the 3-AP injected group with respect to control values. The injection of 3-AP did not alter the levels of aspartate, glutamate, GABA, taurine, glycine, or alanine in the telencephalon on days 7, 14, 21, or 28 and in the diencephalon-mesencephalon on day 21 with respect to control levels.  相似文献   

20.
Blood counts from more than 1000 young-of-the-year rainbow trout, Salmo gairdneri (Richardson), were examined to determine if static exposure to malachite green at 1·35,13·5, or 21·0 mg/1 for 25–30 min or 42·0 or 72·0 mg/1 for 5 min caused chronic leucopaenia. The major changes in fish exposed for 25–30 min came during the first 24 h. After an initial lag of 3·4 h, total leucocyte-thrombocyte counts in both treated and control fish rapidly declined. Recovery was essentially complete 1·4 days after exposure, and no leucopaenia was noted after 14 or 28 days. Thrombocytosis developed during the first 24 h in fish exposed to the higher concentrations. Lymphopaenia and neutrophilia also developed, but abated after the 4th post-treatment day. Leucocyte numbers in control and exposed groups were virtually the same by the 14th day. The total leucocyte-thrombocyte counts in fish exposed for 5 min declined after 24 h, but counts were not as depressed as those in fish exposed for 30 min.
Because leucocyte changes similar to those in exposed fish were evident in the controls in both experiments, we believe that the leucocyte changes in rainbow trout exposed to malachite green were a result of a nonspecific vertebrate stress syndrome, rather than of specific leucocytotoxic effect of this chemical.  相似文献   

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