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121.
We monitored leaf phenology and xylogenesis of 12 Pedunculate oaks in northern Poland in 2014. We hypothesized that the individual trees, which differed in size, age and habitat (tree stand or gap), also diverged in terms of the seasonal patterns of leaf phenology and xylogenesis. The samples used for wood formation observations were collected most frequently during the early leaf phenophases (from March to end of June). The transverse sections of the cambial region were cut with a sledge microtome. We counted the number of cambial cells, measured the width of xylem increment and assessed the timing of xylogenesis and earlywood-vessel formation. We found significant differences in leaf phenology and timing of xylogenesis among individual trees. The smallest differences in wood formation among the trees were observed at the beginning of the vegetation season when the first earlywood vessels were detected (9 days). The dates of completion of the first tangential row of earlywood vessels varied by up to 30 days, while for the completion of the entire earlywood dates varied by up to 32 days. The highest productivity of cambial cells (13 cell layers) was observed around the time of bud swelling at mid-April. In the last days of April, the number of cambial cell layers decreased and subsequently increased again when the leaves were nearly fully expanded at the end of May. To summarize, we observed a high seasonal variability in the number of cambial cell layers. Differences in the time of cessation of cambial activity and xylogenesis amounted to 1 month. We conclude that: (1) oak tree-ring widths and earlywood-vessel sizes and numbers may not be sensitive indicators for early spring temperature and spring defoliation; (2) the missing association between leaf phenophases and xylogenesis as well as the phenological variability may be the reasons for the lack of a clear climatic effect on the above-mentioned parameters.  相似文献   
122.
Among many factors, lipid metabolism within the follicular environment emerges as an important indicator of oocyte quality. In the literature a crucial significance is described concerning follicular fluid (FF) composition as well as messenger RNA (mRNA) expression in follicular cells. The aim of this study was to describe the relationship between oocyte, FF and follicular cells with regard to lipid metabolism. The set of data originating from individual follicles comprised: lipid droplets (LD) number in oocytes (BODIPY staining), mRNA expression of seven genes in cumulus and granulosa cells (SCD, FADS2, ELOVL2, ELOVL5, GLUT1, GLUT3, GLUT8; real time polymerase chain reaction) and fatty acid (FA) composition in FF (gas chromatography). Obtained results demonstrate significant correlation between oocyte lipid droplets number and FA composition in FF. However, gene expression studies show significant correlation between LD number and GLUT1 gene only. Moreover, the present experiment revealed correlations between FA content in FF and expression of several genes (SCD, FADS2, ELOVL5, GLUT8) in granulosa cells, whereas only the SCD gene in cumulus cells. We suggest that the results of our experiment indicate the importance of glucose : lipid metabolism balance, which contributes to better understanding of energy metabolism conversion between oocytes and the maternal environment.  相似文献   
123.
This study evaluated the distribution and signal intensity of a prion protein resistant to proteolysis (PrP(res)) in the brainstem and cerebellum of cattle affected with classical and atypical forms of bovine spongiform encephalopathy (BSE) using a Western immunoblotting technique. In both classical and atypical cases of BSE, a stronger signal was detected in the more rostral brainstem regions relative to the obex. In classical and H-type cases a significant decrease in the PrP(res) signal was found in the cerebellum when compared to that in the obex, whereas L-type BSE cases were characterised by signals of similar intensity in these regions. The uniform distribution of PrP(res) in the region rostral to the obex suggests that when autolysed samples are being tested for BSE, both classical and atypical forms are detectable, even when this target site is missing or cannot be clearly identified. The findings indicate that both the obex and rostral brainstem can be used for BSE diagnosis whereas use of the more caudal brainstem regions and cerebellum is not recommended.  相似文献   
124.
Atypical bovine pestiviruses related to bovine viral diarrhoea virus (BVDV) have recently been detected in cattle from South America, Asia and Europe. The purpose of this study was to compare the clinical and virological aspects of dual infection with BVDV-1 (Horton 916) and an Asian atypical bovine pestivirus (Th/04_KhonKaen) in na?ve calves, in comparison to single infections. Milder clinical signs were observed in the animals infected with single Th/04_KhonKaen strain. Leukocytopenia and lymphocytopenia were observed in all infected groups at a similar level which correlated with the onset of viraemia. Co-infection with both viruses led to prolonged fever in comparison to single strain inoculated groups and simultaneous replication of concurrent viruses in blood and in the upper respiratory tract. Following the infections all the calves seroconverted against homologous strains. Atypical pestiviruses pose a serious threat to livestock health and BVDV eradication, since they may have the potential to be widely spread in cattle populations without being detected and differentiated from other BVDV infections.  相似文献   
125.
AIM: To quantify the chronological sequence of changes in the morphology and immunoreactivity for neurotransmitters in the pylorus of an animal model of infantile hypertrophic pyloric stenosis and phenylketonuria. METHOD: Thirty specimens of pylorus from hph-1 mice and age/sex matched controls (age range: 10-180 days) were examined using conventional histology and immunohistochemistry for a variety of antigens: protein gene product 9.5, a pan neuronal marker; vasoactive intestinal polypeptide; nitric oxide synthase two antigens coalesced to the same inhibitory neurons in humans; substance P, a potent excitatory neurotransmitter; and calcitonin gene related peptide, a neurotransmitter implicated in the somatic afferent innervation of the stomach. The changes in the morphology of the muscle layers were quantified and statistically analysed for each age group (10, 20, 40, 90 and 180 days). RESULTS: Between 10 and 90 days of age, all muscle layers of the hph-1 mice were hypertrophied, for example, 10 days, hph-1 longitudinal muscle mean diameter = 3.4, control = 1.8; hph-1 circular muscle width = 11.5, control = 4.7. The hph-1 mice were significantly smaller during this period (40 days, hph-1 weight = 10 g, control = 25 g). There was no change in the pattern of expression of the antigens examined within the hph-1 mice compared with the controls. CONCLUSION: Hph-1 mice develop a transient smooth muscle hypertrophy of the pylorus attended by gastric distension and failure to gain weight. These changes resolve as the pyloric muscle hypertrophy resolves.  相似文献   
126.
The efficiency of tranfer of maternal immunity and its infuence on the kids' health was observed in a herd in which kids (n=20) had whole contact with the dam (n=13). The factors associated with dam, kid and human, which influence the efficiency of passive transfer were observed. It was estimated that the single-born kids reached higher serum gamma-globulin level (mean 23.14 g/dm3) than twin kids (mean 18.2 g/dm3) (p < 0.05). The gamma-globulin level was the highest in single-born kids at 48 h, and in twin kids in 24 h of life. The IgG class antibodies to herd-homologous strains of Pasteurella multocida and Escherichia coli were estimated using ELISA in sera, colostrum and milk whey samples of dams and sera of kids. It was found that maternal antibodies specific to these two facultative pathogens decreased in kids sera rapidly and the self humoral immune response occurred within the period of observation. Two kids delivered by goats with lowest hierarchic position in the herd showed failure of passive transfer, and died at the 10th and 12th weeks of life due to chronic infections induced by both above mentioned bacterial strains.  相似文献   
127.
Mucins secreted by goblet cells (GC) are the major components of mucus layer coating and protecting gut epithelium. The study aimed at determining the effect of non‐essential amino acids (NEAA) and threonine (Thr) levels on GC number and mucus layer thickness measured in different parts of the gut. A two‐factorial experiment was conducted on 72 pigs (initial BW 12.5 kg) using as factors: Thr level (5.1, 5.7, 6.3 and 6.9 g standardized ileal digestible [SID] Thr/kg) and wheat gluten (WG) level used as a source of NEAA (20.4, 40.4 and 60.4 g WG protein in WG20, WG40 and WG60 diets respectively). All diets covered the requirement for essential AA, except for Thr, and they were fed to six pigs for 20 days. Thr level affected only the count of GC containing acidic mucins in the proximal colon, which was higher in pigs fed a diet with 5.1 g SID Thr/kg in comparison with diet containing 6.3 g SID Thr/kg. In the villi, WG40 and/or WG60 increased the GC number containing acidic mucins and lowered that with neutral mucins in the middle jejunum. In the crypts, higher WG levels decreased the GC number with acidic mucins in the duodenum, ileum and proximal colon and increased that with neutral and mixed mucins in the duodenum and ileum. The mucus layer was thicker in the proximal and middle jejunum in WG20 pigs, whereas in the proximal colon it was thicker in WG60 pigs. The lowest GC count was found in the middle jejunum and the highest in the duodenum and proximal colon. The mucus layer was the thinnest in the proximal and middle jejunum and the thickest in the ileum. The results did not show the negative effect of a moderate Thr deficiency and the positive effect of non‐essential AA supplementation on GC functions.  相似文献   
128.
The aim of the study was to evaluate the influence of dietary supplementation with inulin extract from chicory root and dried chicory root on the protein profile of the renal cortex and medulla of growing pigs. The experiment was carried out on renal cortex and medulla tissue collected from 24 50‐day‐old PIC x Penarlan P76 crossbred piglets (males). Animals were divided into three dietary groups (n = 8) and fed with a control diet, diet supplemented with 2% inulin extract from chicory root and a diet supplemented with 4% dried chicory root. Kidney samples were collected after 40 days of feeding, and renal cortex and medulla proteins were separated by two‐dimensional electrophoresis. Protein identification was performed using MALDI‐TOF mass spectrometry. The diet supplemented with 2% chicory inulin induced significant expression changes of 20 and 26 protein spots in the renal cortex and medulla respectively. Supplementation with 4% dried chicory root triggered changes in the expression of 44 and 24 proteins in the renal cortex and medulla respectively. Both forms of chicory inulin‐type fructans effectively affected the expression of proteins involved in energy metabolism, heat shock proteins and other chaperones, cytoskeletal and cytoskeleton‐related proteins, as well as other proteins. Additionally, changes in transferrin abundance in both experimental groups suggested the significance of chicory fructan supplementation for iron absorption and bioavailability. In conclusion, 2% inulin extract from chicory root and 4% dried chicory root exerted a similar effect on changes in renal protein expression; however, more pronounced alterations were induced by dried chicory root. Nevertheless, further studies are needed for better understanding the mechanism underlying the effect of chicory inulin‐type fructans and their fermentation end products on the kidneys of growing pigs.  相似文献   
129.
Ionizing radiation (IR) is applied to inactivate nuclear genome in the salmonid eggs to induce androgenetic development. However, it has been considered that doses of IR used to damage maternal chromosomes may also affect morphology of the eggs and decrease their developmental potential. Thus, the main goal of the present research was to assess alterations in the rainbow trout (Oncorhynchus mykiss) eggs caused by the high dose of IR administered during androgenesis. In the present research, rainbow trout eggs were irradiated with 350 Gy of X‐rays, inseminated and exposed to the high hydrostatic pressure (HHP) shock to develop as androgenetic doubled haploids (DHs). The distribution of lipid droplets in the irradiated and non‐irradiated rainbow trout eggs, survival rates and morphology of larvae from androgenetic and control groups were compared. It has been observed that non‐irradiated and irradiated eggs exhibited altered distribution of lipid droplets. Most of the eggs before IR treatment displayed rather equal distribution of the oil droplets. In turn, majority of eggs studied after irradiation had coalesced lipid droplets, a pattern found in eggs with reduced quality. Incidences of abnormally developed larvae were more frequently observed among fish that hatched from the irradiated eggs. Observed changes suggest X‐rays applied for the genetic inactivation of rainbow trout eggs may lead to decrease of their developmental competence.  相似文献   
130.
The study was aimed at determining the osteotropic effects of diets containing snail meat as a sole protein source. In our experiment, we tested three different diets incorporating snail meat originating from Helix pomatia (HP), Cornu.aspesa maxima (CAM) and Cornu.aspersum aspersum (CAA) and compared these to a control diet (CON) in which casein was the source of protein. In all diets, the protein content amounted to 10%, as calculated on a dry weight basis. In the study, forty male Wistar rats with an initial body mass of 50 ± 2 g were randomly placed within the control and three experimental groups. After 28 days of experimental feeding, the rats were sacrificed, and the body mass, total skeletal density and body composition were recorded. Moreover, blood serum (osteocalcin, CTX) and isolated tibia (pQCT, DXA, 3D micro‐CT, 3‐point bending test) were stored for further analysis. The results reveal that a diet incorporating snail meat significantly decreased BMC (bone mineral content), as well as area of total skeleton and isolated tibia, and was without influence on BMD (bone mineral density). Furthermore, the 3D micro‐CT analysis of trabecular compartment documented a reduced Tb.Th (trabecular thickness), as well as Tb.N (trabecular number), and an increased Tb.Sp (trabecular separation). Beyond the aforementioned, the snail‐based diets had an influence upon the architectonical properties of the tibia—decreasing its resistance to mechanical loading. Finally, snail meat, when used as an alone source of protein, negatively influenced the metabolism of the bone tissue in growing animals—making bone smaller and weaker.  相似文献   
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