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1.
The distribution and three-dimensional architecture of collagen fibers were compared between pig, goat and chicken livers. Immunohistochemical staining revealed that collagen type I was identified in the interlobular connective tissue region and intralobular areas in pigs and goats. Type III collagen was also identified in the interlobular connective tissue region and intralobular sinusoidal walls. In the chicken liver, only the circumference region of the vessels was immunostained with collagen type I and III antibodies and the interlobular connective tissue wall could not be distinguished clearly. In the intralobular region, collagen type I antibody immunoreacted around the hepatic cells but collagen type III antibody immunoreacted weakly. In the NaOH macerated specimen, well-developed collagen bundles formed the prominent interlobular walls in pigs. In contrast, the wall in the goat liver comprised a thin layer of the bundles. In the chicken liver, there were no notable collagen septa between lobules. The intralobular collagen construction was quite different between the animals, indicating a fragile collagen fibril networks in pigs, a robust framework in goats and dense fabric-like septa in chickens. These results indicate that the distinct collagen frameworks may contribute to the histological strength of the livers in each of the animal species.  相似文献   

2.
During ageing process, multiple changes occur on nervous tissue composed of cells and extracellular matrix. Changes on nervous tissues are usually known as degenerative changes on axon structure and connective tissue covering the nerve such as a decrease in the number of fibre or general structural changes. For this purpose, we have studied age-dependent ultrastructural changes in the rat oculomotor nerve with electron microscopy and also demonstrated collagen structure of the neural sheaths with immunohistochemical techniques. This study was conducted in Gazi University Faculty of Medicine, Department of Anatomy with a total of nine Wistar albino rats. We observed strong collagen type I immunoreactivity in endoneurium and slight to moderate reactivity in fibroblast cytoplasm in 3-month- and 12-month-old groups and mild reactivity in 24-month-old group. Collagen type IV immunoreactivity was stronger in endoneurium and perineurium in the 3-month- and 12-month-old groups compared with collagen type I and fibroblast cytoplasm showed a very strong reactivity. On the other hand, in the 24-month-old group, there was slight reactivity in endoneurium and a strong reactivity in perineurium. NGF staining showed moderate to strong reactivity on Schwann cells of the 3-month-old group. The immunoreactivity decreased in the 12-month- and 24-month-old groups. In the 3-month-old rat group, Schwann cell cytoplasm, mitochondrial structure and neurofilaments were normal. In the 12-month-old group, there were no changes in organelle distribution, mitochondrial structure and neurofilaments, but there was an increase in the connective tissue. An inconsiderable number of degenerated myelinated nerves were observed. We detected an important decrease in the collagen type I immunoreactivity, which could suggest that the endoneurium, perineurium and epineurium are less resistant to the age-related collagen loss and that the peripheral nerve is protected by a weaker barrier in the old group. The collagen type IV immunoreactivity was significantly decreased with age. NGF synthesis decreases with age because of Schwann cell structural degeneration or for different reasons. Thus, this could explain the diminished capacity of regeneration and damage of the myelination of the peripheral nerve.  相似文献   

3.
The proportion of types I and III intramuscular collagen in longissimus muscles of Simmental bulls (n = 8) and steers (n = 8) 17 mo of age was studied. Longissimus samples taken 7 d after slaughter were evaluated for total collagen, types I and III collagen, heat-soluble collagen, sensory panel traits and Warner-Bratzler shear force. Intramuscular collagen (IMC) was isolated and digested with cyanogen bromide, and peptides were resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Percentage of type III IMC was calculated from the total of types I and III collagen as determined from the peak area of densitometric scans of the cyanogen bromide peptides alpha 1(I)CB8 and alpha 1(III)CB8. Longissimus muscles from steers had lower (P less than .05) Warner-Bratzler shear values, less (P less than .05) sensory panel-detectable connective tissue and more (P less than .05) tender panel ratings for muscle fiber tenderness and overall tenderness. Muscles from steers had more (P less than .05) heat-soluble collagen than those from bulls, but no differences (P greater than .05) were found for total collagen and percentage of type III collagen. Some intramuscular-collagen characteristics may have contributed to the less tender muscle of bulls. However, the proportion of types I and III collagen did not account entirely for the tenderness difference between steer and bull muscles. Because there were differences in collagen solubility in muscles from steers and bulls, other collagen characteristics such as crosslinking or fiber size may have been more important than collagen type.  相似文献   

4.
The efficacy of carbon fibres and plasma-preserved tendon allografts for gap repair in the superficial digital flexor tendon in the mid-metatarsal region was evaluated in 12 crossbred calves. Experimental tenectomies were performed, followed by implantation of carbon fibres in group I (12 legs) and plasma-preserved tendon allografts in group II (12 legs). Gross observations in group I showed filling of the defect with granulation tissue with more vascularity on day 7, which was less prominent at day 14. On day 30, the neotendon formed was slightly thicker and comparable to normal tendon in appearance and texture. On day 90, it exhibited all the characteristics of a fully developed tendon. Whereas, in group II increased vascularity at the site and encapsulation of the graft with connective tissue in early periods was observed. The gap between graft and host was filled with fibrous connective tissue. Peritendinous adhesions were maximum on day 7 which were gradually reduced in both groups. Microscopically, an acute inflammatory reaction in the periphery of carbon fibres was observed on day 7. Immature fibroblasts were arranged in a haphazard pattern at this stage. By day 14, numerous newly formed capillaries and comparatively more mature fibroblasts were present in between and around the carbon fibres which were aligning parallel to the longitudinal axis of the tendon. By day 30 the healing tissue exhibited longitudinal orientation of collagen fibres and was at a more advance stage of maturation. By day 90, the neotendon formed simulated the picture of normal tendon. In the grafted tendon group, there was normal healing tissue at the functional sites between host and grafted tendon. The fibroblastic activity appeared to be both extrinsic and intrinsic in origin. The connective tissue had invaded the graft to a variable distance and there was resorption of graft which was replaced by newly formed connective tissue on day 90. Scanning electron microscopic observation revealed formation of neotendon between carbon fibre strands, resulting in thickening of the implant. In later stages parallel collagen fibres resembling normal tendon were observed in both groups.  相似文献   

5.
The removal of the adrenal glands produced a great increase in the number and size of the cytoplasmic processes of the ACTH-immunoreactive cells that sometimes establish contact with those of the neighbouring immunoreactive cells. In addition, in this experimental group, the ACTH-cell percentage and the mean cell, cytoplasmic, and nuclear areas were greatly increased in comparison with those found in control animals. Several regenerated adrenocortical nodules were observed in the small-bowel segment of rats transplanted with neonatal adrenal glands. The percentage and morphometrical values of the pituitary ACTH-reactive cells of this experimental group, although slightly increased relative to the rats with intact adrenals, were greatly decreased in relation to those of the adrenalectomized animals. It is concluded that the neonatal adrenal tissue regenerated after its transplantation into adult rats, a process that modified the percentage, the morphological characteristics, and the morphometrical values of the ACTH-immunoreactive cells of the adrenalectomized rats.  相似文献   

6.
Captive reptiles are routinely identified as reservoirs of Salmonella spp. and the number of reports about reptile-associated salmonellosis is increasing. In the present study, Salmonella were detected in 86 of 159 (54.1%) faecal reptile samples cultured. The percentage of Salmonella positive samples was significantly lower in turtles as compared with lizards and snakes, as Salmonella were only detected in one sample from a single turtle out of 38 turtles investigated. In all, 42 different Salmonella serovars were found. All isolated Salmonella belonged to the species enterica, predominantly to the subspecies I (n=46) and IIIb (n=30), but also to subspecies II (n=3), IIIa (n=6) and IV (n=2). All isolates were sensitive to the antimicrobials examined. A comparison between the reptile owners indicated that either no Salmonella were found, or that Salmonella could be isolated from all or nearly all animals of the respective owners. A significantly higher percentage of Salmonella positive reptiles was detected in the group of owners who purchase reptiles in comparison with pure breeders. A total of 88.9% of Salmonella isolates were found in samples of reptiles bought in pet shops and 58.8% in samples from wild-caught animals. The high percentage of Salmonella in reptiles in our study confirms the risk for the transmission of the infection to humans.  相似文献   

7.
以小花碱茅成熟种子为外植体,研究了脱颖处理和不同激素配比对愈伤组织诱导和分化的影响,成功建立了其组织培养植株再生体系。结果表明,种子脱颖处理显著提高了种子发芽率,降低了污染率;诱导愈伤组织的最佳培养基为添加5.0 mg/L 2,4-D的MS培养基,诱导率可达55.2%,2周可见白色愈伤组织;最佳芽分化培养基为添加1.0 mg/L 6-BA和0.5 mg/L NAA的MS培养基,分化率可达31.7%,同时伴随根毛的发生,生根率达81.7%,诱导时间为2周;分化后的再生苗移植于1/2MS培养基上,100%生根,炼苗移栽后可全部成活。从小花碱茅种子诱导愈伤组织到植株再生共需16周左右。小花碱茅组织培养植株再生体系的建立为进一步探究小花碱茅耐盐碱分子机制奠定了基础。  相似文献   

8.
Following weaning at 24 +/- 1 d of age, crossbred boars were subjected to removal of the cranial cervical ganglia (GX, n = 8) or sham surgery (SHAM, n = 8). At 213 +/- 1 d of age, a catheter was inserted into a jugular vein or vena cava, and all boars were housed in environmentally controlled rooms at 22 degrees C with an equatorial photoperiod. After 2 wk of exposure to this photic environment, samples of plasma and serum were collected at hourly intervals for 24 h. The plasma was assayed for adrenocorticotropic hormone (ACTH) and the serum was assayed for cortisol and melatonin by RIA. The time-trends for all three hormones were described by regression models, which were tested for heterogeneity of regression between SHAM and GX treatments. The circadian rhythm of cortisol in serum was similar for SHAM and GX treatments. The profiles of ACTH were also similar between the two treatments, but circadian changes in concentrations of ACTH paralleling those of cortisol were not evident in either treatment. Overall, concentrations of ACTH were reduced (P = .06) for GX boars compared to SHAM boars. The time-trends of melatonin in serum differed (P less than .001) for GX and SHAM treatments, with a nocturnal rise in melatonin evident in some SHAM boars but not in GX animals. Four SHAM boars had profiles of melatonin that obviously entrained to the light-dark cycle. None of the boars in GX treatment had elevated concentrations of melatonin in serum during the dark period, relative to concentrations during the light.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

9.
Duvaucel geckos (Hoplodactylus duvaucelii) are large endemic lizards that have been extirpated from the New Zealand mainland due to introduced mammalian predators. This species has subsequently become the subject of species translocation conservation management in an endeavour to increase the number of populations and as a part of island ecological restoration. Blood sampling of a captive adult male after tail autotomy led to the discovery of a Rickettsia-like organism within this gecko's erythrocytes. We conclude that this infection was acquired at the gecko's source location, a remote island closed to the general public and lacking potential invasive parasite reservoir reptiles. The likely vector is the native mite Geckobia naultina. This finding represents valuable new baseline information about the health parameters of this threatened species. Particularly in the light of the paucity of reported blood parasitism in New Zealand reptiles, the conservation management of this species through relocation and captive-breeding, and the on-going concerns regarding the introduction of novel parasites to New Zealand.  相似文献   

10.
Meat tenderness is a major factor affecting the consumers’ assessment of meat quality. Collagen is an abundant connective tissue protein and is a contributing factor to variation in meat tenderness and texture. It is found in three specific regions in muscle and in various forms and types. Collagen molecules are bound together through intermolecular crosslinks that help provide structure and strength. These crosslinks are initially reducible, but over time are replaced by mature, thermally stable, and less soluble crosslinks. These mature crosslinks, rather than the total amount of collagen, are the key factors in collagen-related toughness. The proportion of mature to reducible crosslinks increases with age, resulting in older animals that often have less tender meat than younger animals. Collagen crosslinks are also affected by growth rate, nutrition, and genetics. Collagen plays major roles in cooked meat as well. As collagen fibrils are heated during cooking, they shrink, resulting in a fluid loss and less tender meat. They also act to hold muscle fibers together after shrinkage. Post-mortem degradation of collagen and the use of collagenases appear to play a role in providing the desired tenderness and texture by altering the connective tissue structure. Collagen is very important in maintaining acceptable texture; however, high amounts of crosslinks can greatly decrease tenderness and consumer acceptability.  相似文献   

11.
Seventy-two subcutaneous implants were examined to evaluate connective tissue response to Teflon-ensheathed carbon fibers and whole blood clots. Carbon fibers significantly (P less than or equal to 0.001) increased vascularization and collagen formation within the Teflon sheath. Carbon fibers provide a potentially strong scaffold that would physically support cell migration during wound healing. However, obvious foreign body reactions occurred, which indicate that further studies on the biologic features of carbon fiber are needed before carbon fibers become entirely acceptable for long-term implantation. Compared with no-clot controls, Teflon tubes containing only whole blood clots stimulated a significant (P less than or equal to 0.001) wound-healing response, including organized collagen fiber formation. Other variables tested in this study such as length and diameter of the Teflon tubes did not significantly influence connective tissue responses.  相似文献   

12.
The dry and wet weights of the uterus (caruncular and intercaruncular areas) and cervix were measured in non-pregnant (n = 5) and pregnant (n = 25) ewes post mortem; for the latter, five were obtained for each of the 5 months of gestation. The total collagen tissue content was measured in both areas of the uterus and cervix by hydroxyproline analysis and image analysis of Haematoxylin-Van Gieson stained tissue sections. Both wet and dry uterine weights increased significantly with gestational age (P < 0.001). The water content of uterine and cervical tissue remained constant, at between 83 per cent to 85 per cent and 76 per cent to 80 per cent, respectively. There was a close correlation between the two methods used to determine the collagen content (r = 0.96, P < 0.001), and between the increasing weight of the uterus during pregnancy and the total collagen content of tissues (r = 0.97, P < 0.001). At all stages, the total collagen content of the cervix [mean (SEM) 96.2 (5.4) mg g(-1)] was significantly greater (P < 0.001) than that of the caruncular mean [mean (SEM) 24.3 (1.4) mg g(-1)], and the intercaruncular areas [mean (SEM) 29.0 (1.0) mg g(-1)]. The changes in uterine and cervical weights and collagen content of the tissues were similar to those reported in other related species.  相似文献   

13.
This study assessed the effects of suckled sucrose and parenteral carprofen treatment on behavioural measurements of discomfort and serum haptoglobin concentration in lambs following rubber ring castration and/or tail docking. Twenty-eight male and 20 ewe lambs were allocated to either a male or ewe lamb control group (n=4) or to one of three male and two ewe lamb treatment groups (n=8). Male lambs in one treatment group received carprofen subcutaneously (0.5 mg/kg) 30 minutes before castration and docking. Lambs in all other treatment groups suckled sucrose or colostrum immediately before castration and/or tail docking. Behavioural measurements of discomfort were made following castration or tail docking in treatment groups and also in control animals which were not castrated or tail docked. Blood sampling of animals in treatment groups for analysis of serum haptoglobin, an acute phase protein used as an indicator of an acute inflammatory response, was performed before castration or docking and at 24 and 48 hours after castration or docking. Control lambs were blood sampled at 0, 24 and 48 hours following behavioural assessment Neither suckled sucrose nor carprofen treatment altered discomfort behaviour associated with castration or tail docking. Haptoglobin levels following castration or tail docking remained close to the detection limits of the assay and were similar to those recorded in control animals.  相似文献   

14.
用林蛙蝌蚪作实验动物,研究光照和褪黑激素(MT)浓度的变化对蝌蚪头部三角区、尾肌基部、尾肌基部(尾基)尾上鳍、尾肌中部、尾中部尾上鳍和尾尖黑色素颗粒聚集程度的影响,探索利用蝌蚪进行MT定量生物检测的条件。结果表明:控光(黑暗)条件下,头部三角区、尾肌基部、尾基尾上鳍色素细胞色素颗粒较自然光照组聚集程度明显(P<0.05),而尾尖不明显(P>0.05);在相同浓度的MT溶液中,头部三角区处理时间越长,其色素颗粒聚集程度越大(P<0.05),而尾中部尾上鳍不明显(P>0.05);在相同的实验条件下,在0.1～1.0ng/mL浓度范围内,MT浓度与蝌蚪色素细胞黑色素颗粒聚集程度相关,且下午时外源性MT对蝌蚪影响较大。因此,用林蛙蝌蚪作MT定量生物检测方法的模型动物是可行的,且其头部三角区和尾肌基部是较佳的观察、比较部位。  相似文献   

15.
A morphometric ultrastructural study was performed to confirm the presence of an abnormality of the collagen fibrils in a rabbit with a connective tissue defect similar to Ehlers-Danlos syndrome. Median fibril diameter and perimeter were not altered but their ranges were significantly increased. As indicated by the median fibril ‘form factor’, fibrils were significantly more irregular in shape; the range of irregularity in shape was also increased. Fibril periodicity was unchanged. The results are discussed in relation to collagen fibril structure and fibril abnormalities in similar diseases in man and other animals.  相似文献   

16.
This work investigates whether the reproductive performance of Mediterranean goats achieved using melatonin implants at around the spring equinox is affected by the protocol followed, i.e. implanting females only, males only, both sexes or neither sex. In a first experiment, Murciano-Granadina females (n = 419, 510 and 631 for three consecutive years) were divided into four groups: treated with melatonin (FM) and not treated with melatonin (FC), mounted by males treated with melatonin (MM) or not (MC). In a second experiment, performed during 2009, the same protocols were used with 635 Payoya females and the results compared with those obtained for the same year for the Murciano-Granadina breed. Fertility (percentage of goats kidding), litter size (number of kids born per female kidded) and productivity (number of kids per female in each mating group) were calculated. In the first experiment, better reproductive performances were obtained when females (overall fertility: 71.1% vs 57.0% for the FM and FC animals; productivity 1.37 ± 0.04 kids per female vs 1.12 ± 0.03 kids per female for the FM and FC animals; p < 0.01) or males (overall fertility: 65.9% vs 58.4 for the MM and MC animals; productivity 1.28 ± 0.03 kids per female vs 1.13 ± 0.04 kids per female for MM and MC groups, respectively; p < 0.01) were implanted with melatonin. Moreover, the interaction sex × melatonin treatment had a significant effect (p < 0.05) on productivity. In the second experiment, for the Murciano-Granadina breed, the greatest increase in the number of kids born per female was obtained when the females were treated with melatonin, in either the FM/MC or FM/MM protocols (0.54 extra kids and 0.53 extra kids per female, respectively) (p < 0.01). In the Payoya breed, the greatest increase was obtained using the FM/MC protocol (0.19 extra kids per female). Thus, improved reproductive performances are obtained when female Murciano-Granadina and Payoya goats are implanted with melatonin, although important differences in reproductive performance are seen between the breeds.  相似文献   

17.
茧衣对印染废水中染料的吸附和染料再生利用   总被引：1，自引：0，他引：1  
茧衣在酸性条件下含有大量正电荷,对阴离子染料具有很好的吸附作用。研究了不同条件下茧衣对印染废水中的染料活性艳蓝X-BR140%的吸附和再生能力。茧衣对活性艳蓝X-BR140%的吸附作用随pH降低而增加,pH1.5和pH2.0时,茧衣对染料的吸附率分别达到99.22%和99.03%;废水中染料的浓度越高,茧衣对染料的吸附率越大;茧衣对染料的最佳吸附温度为60℃;在pH1.5时,茧衣对染料的吸附率在5min内达到98.94%。再生茧衣在使用过程中基本不损失,且茧衣吸附的染料可以用乙醇处理再生利用,再生染料与原始染料的吸收光谱一致,即染料在再生处理过程中未发生变化。研究认为,茧衣对印染废水中染料的吸附及染料的再生利用具有潜在的应用开发价值。  相似文献   

18.
Sixteen tenorrhaphies were performed at mid-metatarsal region in eight buffalo calves. A 2-cm long gap was created in the superficial digital flexor (SDF) tendon in all animals. The gap was immediately repaired with acellular grafts in animals of group I, 1% glutaraldehyde-preserved tendon allografts in group II, and in group III the defect was repaired with autografts (control group). The contralateral limb in each animal was operated after an interval of 60 days and the animals underwent the same procedure according to the designed groups. Gross observation revealed filling of host tendon-graft junction with fibrous connective tissue. Increased vascularity was seen in group I when compared with group II and III. Graft was resorbed in animals of group I and III, whereas partial absorption of graft was seen in group II. Histological observations on day 30 revealed restoration of cellularity in acellular graft and fragmentation and resorption of glutaraldehyde-preserved graft. Graft was replaced by newly formed fibrous connective tissue. Tissue reaction around polygalactin suture consisted of plasma cells, lymphocytes and macrophages. On day 90, most of the acellular graft was replaced by newly formed fibrous connective tissue. In group II the majority of graft portion remained at the site and was in a state of resorption. In the control group it was difficult to distinguish between the host tendon and the graft. Scanning electron microscopical observation showed densely packed neoformed tissue at host tendon-graft junction. Hydrolysis and invasion of connective tissue between polygalactin suture filaments, resorption of graft with cavity formation and dissolution of ground substance were observed.  相似文献   

19.
Background: Ehlers-Danlos syndrome comprises a group of rare inherited connective tissue diseases characterized by skin hyperextensibility, joint laxity, skin and vessel fragility, and poor wound healing.
Objective: The purpose of this report was to describe the clinical, histologic, and ultrastructural findings in 2 dogs with collagenopathies consistent with Ehlers-Danlos syndrome.
Methods: Two dogs were examined clinically; skin extensibility index was calculated. Skin biopsies obtained from the dorsum were examined by light and electron microscopy.
Results: Both dogs had clinical signs of skin hyperextensibility and fragility, lower skin elasticity, vessel fragility, and poor wound healing. One dog had a hip dislocation, and the other had bilateral medial patellar luxation (grade II), subcutaneous hematomas produced by minimal trauma, and generalized periodontitis. Histologic and ultrastructural examination confirmed abnormalities in the structure and arrangement of collagen fibrils. Fibroblasts were characterized by variable dilatation of the rough endoplasmic reticulum, and anomalous elastic fibers (elaunin fibers) were present in the dermis.
Conclusion: Although the primary defects underlying collagenopathies in animals are still unknown, analysis of the ultrastructural changes in collagen fibrils and clinical findings could facilitate better characterization of these disorders in dogs.  相似文献   

20.
Induction and recovery from inhalation anesthesia of Dumeril's monitors (Varanus dumerili) using isoflurane, sevoflurane, and nitrous oxide (N2O) were characterized using a randomized crossover design. Mean times to induction for isoflurane in 100% oxygen (O2), sevoflurane in 100% O2, sevoflurane in 21% O2:79% nitrogen (N2; room air), and sevoflurane in 66% N2O:34% O2 were 13.00 +/- 4.55, 11.20 +/- 3.77, 10.40 +/- 2.50, and 9.40 +/- 2.80 min, respectively, at 26 degrees C (n = 10). Mask induction with sevoflurane was significantly faster than with isoflurane. There was no significant difference between the induction time for sevoflurane in O2 or in room air, but sevoflurane combined with N2O resulted in significantly faster inductions than were obtained with sevoflurane in 100% O2. All treatments resulted in a significantly higher respiratory rate than in undisturbed animals. There were no significant differences in respiratory rate among lizards receiving O2, isoflurane in 100% O2, sevoflurane in room air, and sevoflurane combined with N2O, but animals receiving sevoflurane in O2 had a lower respiratory rate than those receiving pure O2. The sequence of complete muscle relaxation during induction was consistent and not significantly different among the four treatments: front limbs lost tone first, followed by the neck and the hind limbs; then the righting reflex was lost and finally tail tone. There were no significant differences in recovery times between isoflurane and sevoflurane or between sevoflurane in 100% O2 and sevoflurane combined with N2O. Similar recovery times were observed in animals recovering in 100 and 21% O2.  相似文献   

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