Campylobacter in poultry: filling an ecological niche

Epidemiological studies indicate that Campylobacter species may be responsible for the majority of cases of sporadic gastroenteritis in humans. These studies also suggest that poultry may be one of the most common sources of the bacteria for humans. Campylobacter and related genera in the family Campylobacteraceae are oral and intestinal commensals of vertebrates and some nonvertebrates, a characteristic that complicates rational approaches to controlling Campylobacter contamination of poultry. This review will discuss the phylogeny, genomics, and physiology of campylobacters with the intention of revealing how these organisms have evolved to fill their intestinal ecological niche in poultry and how their physiology must be understood in order to enact effective control strategies.     

Characterization of serum immunoglobulin M of grouper and cDNA cloning of its heavy chain

Immunoglobulin M (IgM) from the whole serum of grouper fish, Epinephelus coioides was purified by affinity chromatography using protein A-Sepharose column. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) under reducing conditions revealed that the relative molecular masses (Mr) of the equimolar heavy and light chains of IgM were 78,000 and 27,000, respectively. The cDNAs encoding IgM heavy chain comprising its variable (VH) and constant (CH) regions have been cloned and sequenced from a grouper kidney cDNA library by antibody screening method. Five VH (130-142 amino acids) and four CH (450-454 amino acids) families were identified. The variable and constant regions were conserved with their putative domains. All the four constant region domains (CH1-CH2-CH3-CH4) contained each three conserved cysteine residues, which are considered to form the inter- and intra-chain disulfide bridges. There were three carbohydrate acceptor sites in the constant region. In general, the pattern of IgM gene organization seems to resemble that of other teleosts. Moreover, the CH genes in grouper IgM occur as multifamily as reported in Atlantic salmon and common carp.     

Hypolipemic effect of water extracts of Picrorrhiza kurroa in high fat diet treated mouse

A hypolipemic effect of the water extract of Picrorrhiza kurroa (PR) was observed in a high fat diet feeding hyperlipemic mouse at doses of 50, 100 and 200 mg/kg, orally, once a day for 12 weeks. Liver weight, serum aspartate transferase (AST), alanine transferase (ALT), low density lipoprotein (LDL), triglyceride and total cholesterol levels were significantly reduced by the treatment. On the contrary, serum HDL level seems not affected by P. kurroa water extract.     

C-reactive protein concentration in dogs with chronic valvular disease

The purpose of the study reported here was to determine whether dogs with chronic valvular disease have increased plasma C-reactive protein concentration, compared with that in clinically normal dogs. Blood was collected from 47 dogs with physical and echocardiographic evidence of chronic valvular disease and from 20 healthy controls. C-reactive protein concentration was determined with a commercial canine C-reactive protein enzyme immunoassay. Compared with controls, dogs with chronic valvular disease had higher plasma concentration of C-reactive protein (median 2.17 microg/mL [range, 0.86-33.8 microg/mL]) versus 1.43 microg/mL [range, 0.84-4.99 microg/mL]; P < .001). C-reactive protein concentration was not related to the presence of congestive heart failure or murmur grade. The results of this study suggest that increased concentration of C-reactive protein is found in dogs with chronic valvular disease.     

Engineering cooperativity in biomotor-protein assemblies

A biosynthetic approach was developed to control and probe cooperativity in multiunit biomotor assemblies by linking molecular motors to artificial protein scaffolds. This approach provides precise control over spatial and elastic coupling between motors. Cooperative interactions between monomeric kinesin-1 motors attached to protein scaffolds enhance hydrolysis activity and microtubule gliding velocity. However, these interactions are not influenced by changes in the elastic properties of the scaffold, distinguishing multimotor transport from that powered by unorganized monomeric motors. These results highlight the role of supramolecular architecture in determining mechanisms of collective transport.     

Transient homologous chromosome pairing marks the onset of X inactivation

Mammalian X inactivation turns off one female X chromosome to enact dosage compensation between XX and XY individuals. X inactivation is known to be regulated in cis by Xite, Tsix, and Xist, but in principle the two Xs must also be regulated in trans to ensure mutually exclusive silencing. Here, we demonstrate that interchromosomal pairing mediates this communication. Pairing occurs transiently at the onset of X inactivation and is specific to the X-inactivation center. Deleting Xite and Tsix perturbs pairing and counting/choice, whereas their autosomal insertion induces de novo X-autosome pairing. Ectopic X-autosome interactions inhibit endogenous X-X pairing and block the initiation of X-chromosome inactivation. Thus, Tsix and Xite function both in cis and in trans. We propose that Tsix and Xite regulate counting and mutually exclusive choice through X-X pairing.     

Detection of Brucella canis and Leptospira interrogans in canine semen by multiplex nested PCR

Brucella canis and Leptospira interrogans are pathogenic bacteria that cause brucellosis and leptospirosis in dogs around the world. Both diseases can be diagnosed serologically, but the direct detection of these organisms in canine semen is needed when it is used for artificial reproduction. We have been attempting the artificial reproduction of guide dogs for greater breeding efficiency and for this purpose have developed a multiplex nested PCR technique for the detection of B. canis and L. interrogans in the semen and cryoprotective agent (CPA). Our results demonstrated the high sensitivity and simplicity of this technique in the detection of these organisms in canine semen and that will be useful in routine diagnosis. Since they have been found to stay alive in canine semen and CPA up to 48 hr, canine semen for breeding purposes should be checked for contamination by the PCR assay.     

Effect of traditional acupuncture on proximal colonic motility in conscious dogs

Acupoints on the Large Intestine Meridian and specific acupoints related with large intestine have been empirically used to treat large intestinal disease. However, the relationship between acupoints related with large intestine and their functions has not been investigated fully. We investigated whether large intestine-related acupoints affect colonic motility in conscious dogs implanted with electrodes at the proximal colon. Manual acupuncture was applied at the following acupoints: 7 main points on the Large Intestine Meridian (LI1, LI2, LI3, LI4, LI5, LI6, and LI11), ST25, BL25 or GV1. Acupuncture at the Large Intestine Meridian acupoints, ST25 and BL25 had no significant effects on the proximal colonic motility. However, acupuncture at GV1 depressed the proximal colonic motility by decreasing the total duration and the frequency of contractile states, which may contribute to the therapeutic effects of GV1. This study also revealed that there was no clear correlation between Large Intestine Meridian and the proximal colonic motility in conscious dogs.