A comparative assessment of culture and serology in the diagnosis of brucellosis in dairy cattle.

To investigate the usefulness of culture for the confirmation of brucellosis in cattle, a comparison of culture and serology was undertaken on 248 animals in four dairy herds where the disease was active. Paired supramammary (SM), retropharyngeal (RP), and internal iliac (IL) lymph nodes were cultured, and five serological tests were deployed: the microserum agglutination test (MSAT), complement fixation test (CFT), the indirect (iELISA) and competitive ELISA, and the fluorescence polarisation assay (FPA). Brucella abortus was isolated from 86.8% of animals on combined culture of all three lymph nodes. Individually, the highest isolation rate was from the RP (90.5% of culture positives). Of culture positive animals, 13.7% and 6.2% were positive from the RP and SM alone, respectively. Approximately half of the positive cultures yielded <10 colonies/culture plate. Although 80.9% of animals were positive in at least one serological test, only 45.2% were positive in all five. For culture-positive animals, the MSAT was the most sensitive test (71.8%). Of the culture-negative animals 67.7% were positive in at least one test, while 12.9% were positive in all five. Titres were higher in animals culture-positive from the SM, and there was a direct correlation between higher titres and higher colony counts in SM cultures. Only 8.9% of animals were both culture-negative and seropositive (in at least one test), while 16.5% were culture-positive and seronegative in all five tests. The results highlight and validate the sensitivity of bacteriological culture in confirming a diagnosis of bovine brucellosis. While the MSAT and FPA were the most sensitive serological tests, a significant percentage of infected animals were undetectable using these standard serological assays.

Extracellular nucleotides affect pericyte-mediated regulation of rat in situ vasa recta diameter.

AIM: We hypothesized that extracellular nucleotides, established as being released from renal tubular epithelial cells, act at pericytes to regulate vasa recta capillary diameter. METHODS: A rat live kidney slice model and video imaging techniques were used to investigate the effects of extracellular nucleotides on in situ (subsurface) vasa recta diameter at pericyte and non-pericyte sites. In addition, RT-qPCR was used to quantify P2 receptor mRNA expression in isolated vasa recta. RESULTS: Extracellular ATP, UTP, benzylbenzyl ATP (BzATP) or 2-methylthioATP (2meSATP) evoked a significantly greater vasoconstriction of subsurface vasa recta at pericytes than at non-pericyte sites. The rank order of agonist potency was BzATP = 2meSATP > ATP = UTP. The vasoconstriction evoked at pericyte sites by ATP was significantly attenuated by the P2 receptor antagonists suramin, pyridoxal phosphate-6-azo(benzene-2,4-disulfonic acid) (PPADS) or Reactive Blue-2 (RB-2). UTP-evoked vasoconstriction at pericytes was attenuated by suramin or RB-2 but not PPADS. Interestingly, suramin or PPADS, when applied in the absence of a P2 receptor agonist, evoked a weak but significant vasoconstriction of vasa recta at pericyte sites, suggesting tonic vasodilation by nucleotides. Significant levels of P2X(1, 3 and 7) and P2Y(4 and 6) receptor mRNA were detected in vasa recta. CONCLUSION: Extracellular nucleotides act at pericytes to cause vasoconstriction of in situ vasa recta. Pharmacological characterization, supported by RT-qPCR data, suggests that P2X(1 and 7) and P2Y(4) receptors mediate nucleotide-evoked vasoconstriction of vasa recta by pericytes. We propose that nucleotides released from renal tubular epithelial cells, in close proximity to vasa recta capillaries, are key in regulating renal medullary blood flow.

Reasons for variations in the use of open access gastroscopy by general practitioners.

This study aimed to investigate the wide variation between general practitioners (GPs) in their use of open access gastroscopy by assessing (i) their partnership share, workload, and the aggregated practice request rate; (ii) correlations with their professional and practice characteristics; and (iii) a comparison with referral rates to medicine, surgery, and all specialties. All 145 GPs and their practice managers were sent a questionnaire and hospital held data on all requests for open access gastroscopy over one year were reviewed. During the year, the 145 GPs made 1210 requests for open access gastroscopy, varying from one to 44 per GP. There were 987,880 practice consultations altogether, an average of 22,451 per practice or 7127 per whole time practitioner. Requests for open access gastroscopy formed 2.4% of all referrals, an average of one per 1000 consultations, or eight per GP. Of a total of 49,123 referrals to all specialties (371 per GP) 4218 (8.5%) were to medicine, and 6444 to surgery (13.1%). The following factors did not correlate with requests: vocational training, a concurrent hospital post, length of service, or receipt of the deprivation allowance by the practice. When the open access gastroscopy referral rate was aggregated for each practice the variation between practices was narrowed to essentially twofold. Requests for open access gastroscopy form a small proportion of all referrals (2.4%). Aggregated practice request rates are relatively uniform compared with the wide variation between individual GPs, suggesting a disproportionate gastroenterology workload between partners. The open access gastroscopy service does not seem to be subject to misuse from most GPs if a variation in practice usage is used as a measure.

Health beliefs and childbirth: is it an illness or a normal life event?

Midwives' health beliefs related to childbirth are often the cause of conflict in the workplace. A review of the literature on the medical model and the normal life event model of childbirth demonstrates the divergence of these beliefs. The medical model considers childbirth an illness, the outcome is measured in perinatal and maternal mortality rates and the mother is a passive patient. The normal life event model considers childbirth a normal process, the outcome is measured in holistic terms and the mother is an active participant.

Health beliefs and children--is it an illness or a normal life event?

Midwives' health beliefs related to childbirth are often the cause of conflict in the workplace. A review of the literature on the medical model and the normal life event model of childbirth demonstrates the divergence of these beliefs. The medical model considers childbirth an illness--the outcome is measured in perinatal and maternal mortality rates and the mother is a passive patient. The normal life event model considers childbirth a normal process--the outcome is measured in holistic terms and the mother is an active participant.

Ceftazidime, a broad spectrum cephalosporin with activity against Ps. aeruginosa.

Ceftazidime is one of the oximinoaminothiazolyl cephalosporins with resistance to most B-lactamases from gram-negative bacteria, and a very wide spectrum of activity including Ps. aeruginosa. MIC's of less than 0.1 mg/l are seen routinely against E. coli, K. pneumoniae, E. cloacae, Proteus spp. both indole positive and negative, Serratia sp., and Providence sp. The mean MIC against clinical isolates of Ps. aeruginosa is less than 2 mg/l. It is bactericidal at concentrations close to the MIC and its activity is unimpaired in the presence of serum. Ceftazidime is well distributed in the body, penetrating into all body fluids at concentrations excess of the MIC's of most pathogenic bacteria. It has a half-life of about 1.5 hours, is excreted almost exclusively by the kidney and is not bound to serum proteins. More than 12,000 patients have now been treated with the antibiotic, with an overall success rate of more than 93%.