Histological differences in full-thickness vs. lamellar corneal pig-to-rabbit xenotransplantation

To evaluate the differences in graft survival and histopathological characteristics between full-thickness and lamellar orthotopic corneal xenotransplantation in a pig-to-rabbit model, we orthotopically transplanted a full-thickness or the anterior half of a pig's cornea onto the OD of 16 rabbits. As a result, the median survival were 16.83 and 29.07 days for the full-thickness and lamellar xenografts, respectively ( P  = 0.0005). Histologically, the full-thickness corneal xenografts had massive infiltration by eosinophils, whereas the lamellar xenografts showed predominantly mononuclear infiltrates ( P  < 0.05). Given these preliminary findings, lamellar corneal xenografts in rabbits survived longer than the full-thickness xenografts and each type of graft demonstrated different rejection mechanisms.     

Evaluation of novel adjuvant Eimeria profilin complex on intestinal host immune responses against live E. acervulina challenge infection

The effects against avian coccidiosis of two novel adjuvants, Quil A/cholesterol/dimethyl dioctadecyl ammonium bromide/Carbopol (QCDC) and QCDC/Bay R1005 (R)/cytosine-phosphate-guanosine (CpG) oligodeoxynucleotides (CpG ODN [T]) (QCDCRT) emulsified with profilin, a conserved Eimeria recombinant protein, were determined in broiler chickens. Chickens were subcutaneously immunized with isotonic saline (control group), profilin (P), profilin emulsified with QCDC (P-Q), or profilin with QCDCRT (P-QR) at 2 and 9 days post-hatch and orally challenged with 1.0 x 10(4) sporulated oocysts of Eimeria acervulina (EA) at 7 days postimmunization. All profilin-immunized groups showed increased body weight gain when compared to the control group, and the P-QR group had significantly higher body weight gain than did those of the P and P-Q groups following EA challenge infection. All groups immunized with profilin showed significantly decreased intestinal lesions compared with the control group, with the P-QR group showing the lowest intestinal lesions among the profilin-treated groups. Finally, the P-QR group showed greater CD4+/CD8+ and TCR1+/TCR2+ splenocytes and higher antiprofilin serum antibody titers compared with the P and P-Q (or both) groups following EA challenge infection. These results further suggest that vaccination of chickens with profilin, in combination with the QCDCRT adjuvant, may provide a novel control strategy against EA infection in commercial flocks.     

Recent advances in immunomodulation and vaccination strategies against coccidiosis

Coccidiosis is a ubiquitous intestinal protozoan infection of poultry seriously impairing the growth and feed utilization of infected animals. Conventional disease control strategies rely heavily on chemoprophylaxis, which is a tremendous cost to the industry. Existing vaccines consist of live virulent or attenuated Eimeria strains with limited scope of protection against an ever-evolving and widespread pathogen. The continual emergence of drug-resistant strains of Eimeria, coupled with the increasing regulations and bans on the use of anticoccidial drugs in commercial poultry production, urges the need for novel approaches and alternative control strategies. Because of the complexity of the host immunity and the parasite life cycle, a comprehensive understanding of host-parasite interactions and protective immune mechanisms becomes necessary for successful prevention and control practices. Recent progress in functional genomics technology would facilitate the identification and characterization of host genes involved in immune responses as well as parasite genes and proteins that elicit protective host responses. This study reviews recent coccidiosis research and provides information on host immunity, immunomodulation, and the latest advances in live and recombinant vaccine development against coccidiosis. Such information will help magnify our understanding of host-parasite biology and mucosal immunology, and we hope it will lead to comprehensive designs of nutritional interventions and vaccination strategies for coccidiosis.     

Cross-reactivities with Cryptosporidium spp. by chicken monoclonal antibodies that recognize avian Eimeria spp

In a previous study, we have developed several chicken monoclonal antibodies (mAbs) against Eimeria acervulina (EA) in order to identify potential ligand molecules of Eimeria. One of these mAbs, 6D-12-G10, was found to recognize a conoid antigen of EA sporozoites and significantly inhibited the sporozoite invasions of host T lymphocytes in vitro. Furthermore, some of these chicken mAbs showed cross-reactivities with several different avian Eimeria spp. and the mAb 6D-12-G10 also demonstrated cross-reactivities with the tachyzoites of Neospora caninum and Toxoplasma gondii. Cryptosporidium spp. are coccidian parasites closely related to Eimeria spp., and especially C. parvum is an important cause of diarrhea in human and mammals. In the present study, to assess that the epitopes recognized by these chicken mAbs could exist on Cryptosporidium parasites, we examined the cross-reactivity of these mAbs with Cryptosporidium spp. using an indirect immunofluorescent assay (IFA) and Western blotting analyses. In IFA by chicken mAbs, the mAb 6D-12-G10 only showed a immunofluorescence staining at the apical end of sporozoites of C. parvum and C. muris, and merozoites of C. parvum. Western blotting analyses revealed that the mAb 6D-12-G10 reacted with the 48-kDa molecular weight band of C. parvum and C. muris oocyst antigens, 5D-11 reacted the 155 kDa of C. muris. Furthermore, these epitopes appeared to be periodate insensitive. These results indicate that the target antigen recognized by these chicken mAbs might have a shared epitope, which is present on the apical complex of apicomplexan parasites.     

Performance of growing-finishing pigs fed diets containing Roundup Ready corn (event nk603), a nontransgenic genetically similar corn, or conventional corn lines

Two studies were conducted at two locations to evaluate growth performance and carcass characteristics of growing-finishing pigs fed diets containing either glyphosate-tolerant Roundup Ready (event nk603) corn, a nontransgenic genetically similar control corn (RX670), or two conventional sources of nontransgenic corn (RX740 and DK647). A randomized complete block design (three and four blocks in Studies 1 and 2, respectively) with a 2 x 4 factorial arrangement of treatments (two genders and four corn lines) was used. Study 1 used 72 barrows and 72 gilts (housed in single-gender groups of six; six pens per dietary treatment) with initial and final BW of approximately 22 and 116 kg, respectively. Study 2 used 80 barrows and 80 gilts (housed in single-gender groups of five; eight pens per dietary treatment) with initial and final BW of approximately 30 and 120 kg, respectively. Pigs were housed in a modified open-front building in Study 1 and in an environmentally controlled finishing building in Study 2. The test corns were included at a fixed proportion of the diet in both studies. Animals had ad libitum access to feed and water. Pigs were slaughtered using standard procedures and carcass measurements were taken. In Study 1, overall ADG, ADFI (as-fed basis), and gain:feed (G:F) were not affected (P > 0.05) by corn line. In Study 2, there was no effect of corn line on overall ADFI (as-fed basis) or G:F ratio. In addition, overall ADG of barrows fed the four corn lines did not differ (P > 0.05); however, overall ADG of gilts fed corn DK647 was greater (P < 0.05) than that of pigs fed the other corn lines. There was no effect (P > 0.05) of corn line on carcass yield or fatness measurements in either study. Differences between barrows and gilts for growth and carcass traits were generally similar for both studies and in line with previous research. Overall, these results indicate that Roundup Ready corn (nk603) gives equivalent animal performance to conventional corn for growing pigs.     

Cytology of Cork Layer Formation of Citrus and Limited Growth of Elsinoe fawcettii in Scab Lesions

Ultrastructural aspects of host–parasite interactions were investigated in fruits and leaves of citrus (satsuma mandarin) infected with Elsinoe fawcettii. Fungal infection induced host tissues to form cork layers bordering the necrotic areas below the infected sites. The cork layers were composed of compact host cells with convoluted cell walls and alternating lamellations, indicating ligno–suberized tissues in the wound periderm. No host tissues below the cork layers were invaded by hyphae. Hyphae grew intercellularly and intracellularly, often causing hypertrophy and compartmentalization of infected host cells. Also, host cells adjacent to invading hyphae showed accumulation of electron-dense materials and the formation of host cell wall protuberances in intercellular spaces. Hyphae had concentric bodies that showed an electron-transparent core surrounded by an electron-dense layer with radiating filamentous structures on their surface. One or more intrahyphal hyphae were found in the cytoplasm of intercellular or intracellular hyphae. These results suggest that the ligno–suberized cork layers in the wound periderm of citrus act as a protective barrier, which leads to restricted growth of E. fawcettii in bordered scab lesions. The fungus is thought to form concentric bodies and intrahyphal hyphae as a survival mechanism against the water- and nutrient-deficient environments that occur in the cork layers of necrotic host parts.     

Morphological characteristics of C1 and C2 adrenergic neurone groups in marmoset monkey brainstem by using antibody against phenylethanolamine-N-methyltransferase

This work describes a mapping study of phenylethanolamine-N-methyltransferase (PNMT) immunoreactive neurones and fibres in the medulla oblongata of the marmoset monkey, Callithrix jacchus. Two groups of PNMT-immunoreactive neurones were found in the marmoset monkey medulla oblongata: a ventrolateral (C1 group) and a dorsomedial PNMT-immunoreactive cells group (C2 group). The PNMT-immunoreactive cells in the ventrolateral group C1 were found to be located around the lateral reticular nucleus. The PNMT-immunoreactive somata within the ventrolateral medulla are round to oval, and mostly multipolar with branched processes. In the dorsomedial group C2, PNMT-immunoreactive cell bodies appeared near the obex. The majority of the dorsomedial PNMT-immunoreactive neurones were observed in the nucleus tractus solitarius; although some were present in the dorsal motor nucleus of the vagus. The PNMT-immunoreactive somata in the dorsomedial medulla were small and round or ovoid. These results provide information upon the adrenergic system in the medulla oblongata of a species that presents a useful model of a small primate brain, the marmoset monkey.     

无辣品种(系)中的辣椒素合成酶的基因缺失有利于用SCAR标记早期检测辣度

用辣椒品种ECW123R(C.annuum)与CM334(C.annuum)杂交,对其121个F2代单株进行的检测表明,辣椒素合成酶基因(CS)与C位点的共分离控制了辣味的表达.故我们认为CS与C紧密连锁.对四个辣味型品种和四个无辣味型品种的测序分析表明,无辣味型品种在CS的5'上游区有一长度为2529bp的缺失(基因序列)存在.我们已研究出该C位点的分子标记,可在植株苗期检测其辣度.根据该缺失序列,我们开发了5个SCAR标志,其中有两个为共显性.这些SCAR标记对早期检测无辣味型个体既方便又准确.     

Doublecortin-immunoreactive neuronal precursors in the dentate gyrus of spontaneously hypertensive rats at various age stages: comparison with Sprague-Dawley rats

Spontaneously hypertensive rats (SHRs) are widely accepted in medical research because this model has been used for studies in neurodegenerative diseases such as vascular dementia and stroke. In the present study, we observed newly generated neuronal precursors using doublecortin (DCX, a marker of neural proliferation and differentiation) in the subgranular zone of the dentate gyrus in SHRs compared to Sprague-Dawley rats (SDRs) at various age stages. DCX immunoreactivity, immunoreactive cell numbers and its protein level in the dentate gyrus of the SHRs were higher than those in the SDRs at postnatal month 1 (PM 1). At PM 8, DCX immunoreactivity, immunoreactive cell numbers and protein levels in both groups were markedly decreased compared to those at PM 1; however, they were higher than those in the SDRs. They were decreased in the both groups with age: DCX immunoreactive cells in the SDRs were few at PM 12. Our results indicate that newly generated neuronal precursors are more abundant in SHRs than in SDRs during their life.     

Differences in lipid peroxidation and Cu,Zn-superoxide dismutase in the hippocampal CA1 region between adult and aged dogs

Reactive oxygen species have been long associated with oxidative stress relevant to many pathological damages. In brain, 4-hydroxy-2E-nonenal (HNE), a major cytotoxic end product of lipid peroxidation, is produced. In contrast, superoxide dismutase (SOD), one of the major antioxidant enzymes, protects neurons from oxidative stress. The aim of this study is to observe differences in the distribution of HNE and Cu,Zn-superoxide dismutase (SOD1) in the hippocampal CA1 region of adult (2-3 years of age) and aged (10-12 years of age) dogs. The HNE immunoreactivity and protein level in the CA1 region were significantly high in the aged dogs compared to those in the adult dogs. SOD1 immunoreactivity and its protein level were also higher in the aged dogs than those in the adult dogs. However, there were not significant differences in NeuN (a neuron-specific soluble nuclear antigen) immunoreactivity in CA1 neurons between the adult and aged dogs. These differences may be associated with oxidative stress in aged dogs compared to that in adult dogs.