Detection of polymorphism and sequence characterization of Toll-like receptor 7 gene of Indian goat revealing close relationship between ruminant species

In this study, approximately 3.4 kb nucleotide sequence of caprine TLR7 (Toll-like receptor 7) gene was generated from twelve different Indian goat breeds belonging to different geographical regions. Goat TLR7 gene ORF (Open Reading Frame) was found to be 3141 nucleotides long coding for 1046 amino acids similar to sheep. The sequence analysis at nucleotide level revealed goat TLR7 having 99.5% homology with sheep, followed by other livestock species. Simple Modular Architecture Research Tool (SMART) was used for the structural analysis of goat TLR7 that showed the presence of 22 leucine rich repeats (LRRs) along with single Toll/interleukin-1 receptor (TIR) domains. TIR domain, when compared, was found to be similar in ruminant species, goat, sheep, cattle, and buffalo. The phylogenetic analysis also revealed grouping of all ruminant species together, goat being closer to sheep followed by cattle and buffalo. A total of 22 polymorphic sites were observed in TLR7 gene of 24 goats representing 12 different breeds, out of which 19 were present within the coding region and three in 3'UTR. Out of the seven nonsynonymous SNPs, two were in ectodomains and one in TIR domain. Overall our results indicate substantial variation within goat TLR7 gene, which could be exploited for association with disease susceptibility.

Chronic alterations in rat brain α-adrenoceptors following traumatic brain injury

Norepinephrine (NE) has been implicated in cerebral plasticity and recovery of function after brain injury. To examine the status of noradrenergic mechanisms in the brain following traumatic brain injury (TBI), male Sprague-Dawley rats underwent right sensorimotor cortex contusions and were observed for the next 30 days for recovery of motor function by measurement of the time taken to perform a modified beam walking task! At 30 days, their brains were assayed by receptor autoradiography for αr- and α2-adrenoceptor binding with 1 nM [3H]prazosin and 1 nM [3H]paraminoclonidine, respectively. One day after contusion, TBI rats took 60% longer to run the beam than sham-lesioned controls. Run times were directly proportional (r = 0.784; P = 0.012) to lesion volume determined at 30 days. The motor deficit persisted for 8 days, after which TBI and control rats had similar run times, largely due to increased run times in sham rats. At 30 days, TBI rats had a generalized, bilateral decrease in [3H]prazosin binding across all brain areas read (F[l,13] = 9.23; P = 0.009) with specific 12%-21% decreases in the cortex contralateral to the lesion and bilaterally in the dorsomedial hypothalamic and three thalamic nuclei. On the other hand, [3H]paraminoclonidine binding did not differ from sham lesion controls in any brain area of TBI rats. Thus, unilateral TBI is followed by widespread, bilateral changes in α1-adrenoceptor binding which would leave the animal vulnerable to any factors which reduced the access of NE to its postsynaptic adrenoceptors. This is compatible with the observation that α1-antagonists and α2-agonists can transiently reinstate the motor deficit after recovery has occurred.

Selectivity enhancement for glutamate with a Nafion/glutamate oxidase biosensor

Response properties and selectivity are reported for glutamate biosensors constructed with a film of Nafion between the platinum anode and a layer of immobilized glutamate oxidase. The effects of enzyme loading, sample pH and temperature are established. Operation at pH 7.8 and 37 degrees C results in linearity up to 800 muM and a limit of detection of 0.3 muM. Nafion enhances selectivity for glutamate over test species that include ascorbic acid, uric acid and acetaminophen. Selectivity enhancement was greater over the anionic interferences because of electrostatic repulsion and the extent of this enhancement depends on the thickness of the Nafion layer. Even under ideal conditions, some interfering signal is observed when glutamate levels are ten-times less than ascorbate.

Establishment of an animal model of extracorporeal membrane oxygenation in rabbits

OBJECTIVE

This study was undertaken to establish an animal model of extracorporeal membrane oxygenation in rabbits.

METHODS

Ten New Zealand white rabbits weighing 2573±330 g were used in this study. Extracorporeal membrane oxygenation was established in these animals through cannulation of the right carotid artery and jugular vein for arterial perfusion and venous return. The components of the perfusion circuit were specially designed. Arterial blood pressure was measured with a blood pressure meter through cannulation of the right femoral artery. The heart rate and blood gas parameters were also monitored by electrocardiography and a blood gas analyzer (Radiometer ABL800, Bronshøj, Denmark), respectively.

RESULTS

The rabbit model of extracorporeal membrane oxygenation was established successfully. The hemodynamic and blood gas parameters were changed within an acceptable range during the extracorporeal membrane oxygenation process. The specially designed miniature membrane oxygenator was sufficient to meet the extracorporeal membrane oxygenation needs in this animal model.

CONCLUSION

The rabbit model of extracorporeal membrane oxygenation established through right carotid artery and jugular vein cannulation is feasible, easily operated and economical. It is an ideal model for further research of the pathophysiology and organ protection offered through the application of extracorporeal membrane oxygenation.

First Report of Chrysanthemum chlorotic mottle viroid in Chrysanthemum in China

During the spring of 2008, a chrysanthemum plant showing mild mottle on young leaves was observed in a garden in Beijing, China. After the plant was moved into a greenhouse, symptoms became severe with obvious yellowing and complete chlorosis on new leaves. In addition, when a survey was conducted for chrysanthemum diseases in 2010, plants with mild chlorotic spots on leaves were also found occasionally in a commercial field in Hainan, China. These symptoms resembled symptoms induced by Chrysanthemum chlorotic mottle viroid (CChMVd). Therefore, total RNA of 13 samples collected from Beijing (cultivar unknown) and Hainan (cv. Golden) was extracted according to Li et al. (2) and tested for CChMVd by northern blot hybridization using DIG-labeled CChMVd cRNA probe (1). All samples were CChMVd positive, and the healthy control was negative. The viroid was further confirmed by reverse transcription (RT)-PCR using CChMVd specific primers (forward: 5'-AGGTCGTA(T)AAACTTCCCCTCTAAA(G)CG-3', homologous to nucleotides 134 to 159; and reverse: 5'-TCCAGTCGAGACCTGAAGTGGGTTTC-3', complementary to nucleotides 133 to 108) (1). Two amplified products of approximately 400 bp were cloned into the pGEM-T vector (Promega, Madison, WI) and transformed into E. coli DH5α competent cells. Two positive clones were obtained from each isolate and sequenced. Four sequences obtained have been submitted to GenBank (Accession Nos. HQ891014 to HQ891017). Sequence analysis revealed that the obtained sequences shared 96.49 to 96.99% similarity with the reference sequence CChMVd (GenBank Accession No. NC003540). All the clones are 399 nucleotides long and are thought to be the symptomatic type based on their UUUC sequence at positions 82 to 85 in the CChMVd tetraloop (1). In addition, both isolates were mechanically inoculated to three healthy chrysanthemum plants of the unknown cultivar from Beijing. All inoculated plants developed chlorosis after 5 weeks and CChMVd infections were confirmed by northern blot hybridization and RT-PCR. CChMVd is an important pathogen that may potentially cause losses to the chrysanthemum industry. It is necessary to survey for CChMVd infection in various chrysanthemums cultivated in China. To our knowledge, this is the first report of CChMVd in chrysanthemum in China. References: (1) P. M. De la Pena et al. Proc. Natl. Acad. Sci. USA. 96:9960, 1999. (2) S. F. Li et al. Ann. Phytopathol. Soc. Jpn. 61:381, 1995.

Cell apoptosis of taste buds in circumvallate papillae in diabetic rats

Diabetes mellitus may result in taste disturbance. The present study has revealed that cell apoptosis of taste buds in circumvallate papillae may contribute to the taste disturbance in a rat model of type2 diabetes. Type2 diabetes was induced in Wistar rats by feeding them with a high-fat diet (30% fat), and a single intraperitoneal injection of streptozotocin (30 mg/kg). The increased cell apoptosis of taste buds in circumvallate papilla sections was detected by TUNEL staining in diabetic rats, and the ultrastructure was further examined by transmission electronic microscopy. Immunohistochemical and Western blot analyses revealed the downregulation of Bcl-2, upregulation of Bax, and increased activation of caspase-9 and -3, in diabetic rats, indicating that the apoptosis of taste bud cells may be mediated via the intrinsic mitochondrial pathway in diabetics.

Non-archetypal Type II-like and atypical strains of Toxoplasma gondii infecting marsupials of Australia

Australia is geographically isolated and possesses a remarkable diversity of wildlife species. Marsupials are highly susceptible to infection with the cosmopolitan parasite Toxoplasma gondii. Of 46 marsupials screened for T. gondii by multilocus PCR-DNA sequencing at polymorphic genes (B1, SAG3, GRA6, GRA7), 12 were PCR-positive; the majority (67%; 9/12) were infected by non-archetypal Type II-like or atypical strains. Six novel alleles were detected at B1, indicating greater diversity of genotypes than previously envisaged. Two isolates lethal to marsupials, were avirulent to mice. The data support the conclusion that Australia's isolation may have favoured the persistence of non-archetypal ancestral genotypes.

Temporal expression of alternatively spliced forms of tissue factor pathway inhibitor in mice

BACKGROUND

Mouse tissue factor pathway inhibitor (TFPI) is produced in three alternatively spliced isoforms that differ in domain structure and mechanism for cell surface binding. Tissue expression of TFPI isoforms in mice was characterized as an initial step for identification of their physiological functions.

METHODS AND RESULTS

Sequence homology demonstrates that TFPIalpha existed over 430 Ma while TFPIbeta and TFPIgamma evolved more recently. In situ hybridization studies of heart and lung did not reveal any cells exclusively expressing a single isoform. Although our previous studies have demonstrated that TFPIalpha mRNA is more prevalent than TFPIbeta or TFPIgamma mRNA in mouse tissues, western blot studies demonstrated that TFPIbeta is the primary protein isoform produced in adult tissues, while TFPIalpha is expressed during embryonic development and in placenta. Consistent with TFPIbeta as the primary isoform produced within adult vascular beds, the TFPI isoform in mouse plasma migrates like TFPIbeta in SDS-PAGE and mice have a much smaller heparin-releasable pool of plasma TFPIalpha than humans.

CONCLUSIONS

The data demonstrate that alternatively spliced isoforms of TFPI are temporally expressed in mouse tissues at the level of protein production. TFPIalpha and TFPIbeta are produced in embryonic tissues and in placenta while adult tissues produce almost exclusively TFPIbeta.

Favoring Trauma as an Etiological Factor in Denture Stomatitis

The etiology of denture stomatitis remains controversial. Trauma due to unstable dentures has been suggested as an etiological factor. Therefore, we tested the hypothesis that the prevalence of denture stomatitis is reduced when mandibular dentures are stabilized by implants. Data were collected at a one-year follow-up from 173 edentulous elders who had randomly received mandibular implant overdentures or conventional dentures. The diagnosis of denture stomatitis was determined according to the Newton classification. Elders wearing conventional dentures were almost 5 times more likely to have denture stomatitis than those wearing mandibular two-implant overdentures ( P < 0.0001, Fisher’s exact test). Adjusted odds ratios showed that only the type of the prosthesis (AOR = 4.54, 95% CI 2.20 to 9.40) and nocturnal wear (AOR = 3.03, 95% CI 1.24 to 7.40) predict the frequency of denture stomatitis. Thus, implant overdentures may reduce oral mucosal trauma and control denture stomatitis.

Gene transfer of antisense B7.1 attenuates acute rejection against splenic allografts in rats

Blockade of CD80-CD28 costimulatory pathway induces unresponsiveness of T cells to alloantigens and protects allografts against immune rejection in numerous animal models. The aim of this study was to investigate whether blocking expression of B7.1 (CD80) on donor splenocytes by an antisense technique protected splenic allografts against immune rejection. Splenic grafts from Wistar-Furth rats were intra-arterially transfused with an antisense B7.1 expression vector, before they were transplanted into Sprague-Dawley rats. The rats were sacrificed at scheduled times, and the splenic allografts histologically examined. Antisense gene transfer resulted in marked down-regulation of B7.1 in donor spleens, hyporesponsiveness of recipient T cells, and attenuated acute immune rejection against splenic allografts. No obvious damage to skin, liver, or gut due to graft-versus-host disease was detected in the recipients. In conclusion, blocking expression of B7.1 in donor spleens by antisense gene therapy represented a potential alloantigen-specific immunosuppressive strategy to inhibit acute rejection against splenic allografts.