Evaluation of a point-of-care calcium device in bovine plasma and serum.

Hypocalcemia is a common metabolic disease in dairy cows, and it is defined as total calcium (tCa) blood concentration <2.0 mmol/L. The alternatives for the gold standard test to measure tCa in bovine blood are limited. Therefore, our objective was to compare the performance of the calcium (Ca) point-of-care compact analyzer (POC; ARKRAY Inc.) device with the gold standard method to measure bovine blood tCa concentration. Blood samples (n = 151) from dairy cows were collected within 24 h postpartum from multiparous and primiparous dairy cows for serum and plasma. Then, serum and plasma were stored at -80°C until further analyses with the gold standard method on an automatic analyzer (Cobas C501 analyzer; Roche Diagnostics) and the POC device. The tCa blood concentration was measured in the laboratory in plasma and serum samples using both methods within 10 mo of sample collection. Correlation coefficients (Spearman), coefficients of variation (CV, %), sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, Passing and Bablok regression, and Bland-Altman agreement test were performed between the gold standard and the POC device. The range and median tCa plasma concentrations measured with the POC device were 1.1 to 2.8 mmol/L and 2.4 mmol/L, respectively. The range and median tCa serum concentrations measured with the POC device were 1.1 to 2.7 mmol/L and 2.3 mmol/L, respectively. The tCa blood concentrations range and median with the gold standard were 1.1 to 2.6 mmol/L and 2.3 mmol/L. The hypocalcemia prevalence of our study population was 11.2%. The CV were 1.89% and 0.55% for low and high tCa in plasma samples measured with the POC, respectively. The CV were 2.57% and 1.58% for low and high tCa in serum, respectively. The Spearman correlation coefficient showed a strong correlation between the gold standard and the POC device for both serum and plasma tCa concentration. The sensitivity of the POC device for both plasma (41.1%) and serum (64.7%) Ca was poor. However, the specificity of the POC device was perfect in plasma (99.2%) and serum (99.2%). The PPV in plasma and serum were 87.5% and 91.6%, respectively. Negative predicted values were 93.0% and 95.6% in plasma and serum. The mean (95% CI) difference between the gold standard and the POC device in plasma and serum were 0.35 (-0.52, 1.23) mmol/L and 0.19 (-0.53, 0.92) mmol/L, respectively. Finally, we observed a strong correlation between the POC device and the gold standard method for tCa plasma and serum. However, the clinical application of the POC device should be carefully considered because its ability to detect cows with hypocalcemia in serum or plasma samples was poor. However, the device performed better than previously analyzed POC devices and needs further improvement to be a valuable tool for the dairy industry.

Widespread Wolbachia infection in an insular radiation of damselflies (Odonata, Coenagrionidae).

Wolbachia is one of the most common endosymbionts found infecting arthropods. Theory predicts symbionts like Wolbachia will be more common in species radiations, as host shift events occur with greatest frequency between closely related species. Further, the presence of Wolbachia itself may engender reproductive isolation, and promote speciation of their hosts. Here we screened 178 individuals belonging to 30 species of the damselfly genera Nesobasis and Melanesobasis - species radiations endemic to the Fiji archipelago in the South Pacific - for Wolbachia, using multilocus sequence typing to characterize bacterial strains. Incidence of Wolbachia was 71% in Nesobasis and 40% in Melanesobasis, and prevalence was also high, with an average of 88% in the Nesobasis species screened. We identified a total of 25 Wolbachia strains, belonging to supergroups A, B and F, with some epidemic strains present in multiple species. The occurrence of Wolbachia in both males and females, and the similar global prevalence found in both sexes rules out any strong effect of Wolbachia on the primary sex-ratio, but are compatible with the phenotype of cytoplasmic incompatibility. Nesobasis has higher species richness than most endemic island damselfly genera, and we discuss the potential for endosymbiont-mediated speciation within this group.

Calf care personnel on dairy farms and their educational opportunities.

As dairy herd sizes become larger and the organization of the business more complex, targeting communication and education to enhance animal care becomes more difficult. The purpose of this study was to describe selected demographics of calf care employees on large (>500 animals) and small (<501 animals) dairy farms that raise their own calves. Two to 8 individuals per farm involved with calf care, including owners, veterinarians, and calf managers, feeders, and treaters, were interviewed in either English or Spanish. Interviews were conducted in person on 53 dairy farms located in Arizona, Idaho, New York, Oregon, and Washington State. The number of preweaned calves on the farm ranged from 9 to 1,500 (median = 93). A total of 224 individuals were interviewed across 8 job titles. As farm size increased, personnel structure became more complex. Farms with >100 preweaned calves were 15 times more likely to have a calf manager title compared with farms with ≤100 preweaned calves. Eight farms designated the same person as calf manager, treater, and feeder, all with ≤100 preweaned calves. Thirty-two (60%) of the farms had at least 1 full-time calf feeder. Almost 30% of owners and over 40% of veterinarians interviewed were over 50 yr of age, whereas over 40% of the calf managers, feeders, and treaters were under 30 yr of age. Seventy-three percent of feeders and 72% of treaters spoke Spanish at home. For languages in which interviewees were comfortable speaking, more than 30% of owners and 33% of veterinarians were comfortable communicating in Spanish. For calf care employees, 60% of calf managers, 42% of feeders, and 38% of treaters were bilingual (English and Spanish), but most (72%) preferred to be interviewed in Spanish. The level of education varied by job title for those interviewed, but most of the calf care team had high school or less education. However, some diversity was observed in educational background within job title with almost 38% of the calf managers having at least some college education. The majority of feeders (88%) and treaters (83%) reported being trained by another employee and 66 and 58%, respectively, had not received any continuing education in the previous year. With the amount of diversity seen on these farms, understanding employees' educational backgrounds, language, and generational differences may be valuable when developing training for new procedures for animal health or other aspects of animal care.

Escherichia coli O157:H7--Discerning Facts from Fiction: An Integrated Research and Extension Project for Multiple Audiences.

The O157:H7 (EcO157) epidemiology of Shiga-toxin-producing Escherichia coli (STEC) in cattle is complex, and myths about pre-harvest control are perpetuated. The objectives of this project were to identify perpetuated misinformation and inform four audiences about evidence-based risks and pre-harvest control of EcO157 by addressing: (i) EcO157 epidemiology and pre-harvest control; (ii) how food safety policy is created; and (iii) how to present accurate information about EcO157. An environmental scan using a daily Internet search helped identify themes for education. A literature review of pre-harvest control measures contributed to the development of educational materials (fact sheets, website, web presentations and conferences). Conference 1 was a webinar with 315 registrants, 10 countries including 41 US states and four Canadian provinces. Most participants felt confident in using their new knowledge, more than half felt confident enough to answer EcO157 questions from the public and many would recommend the recorded version of the webinar to colleagues. Conference 2 was live in the Washington, DC, area with most participants employed by the US government. All agreed that they better understood pre-harvest control, how food safety policy was made, and were confident they could create an effective message about STEC pre-harvest control. Videos were posted and received 348 Internet visitors within 2 months. Conference 3 was a webinar with a live audience and Twitter feeds, targeting people who give nutrition advice. Almost all ranked the programme good to excellent and relevant to their work. About 25% indicated that they would share: 'grass-fed beef is not safer than grain-fed', 25% would share information on effectiveness of cattle vaccines, and 14% would share information on message mapping. Across all conferences, major changes in knowledge included the following: there is no additional risk of EcO157 shedding from grain-fed versus grass-fed cattle, pre-harvest vaccination is efficacious, and production systems (pasture versus confinement) do not affect EcO157 shedding rates.

Ureteric stents: investigating flow and encrustation.

Blockages of the ureter, e.g. due to calculi (kidney stones), can result in an increase in renal pelvic pressure. This may be relieved by inserting a stent (essentially a permeable hollow tube). However, a number of complications are associated with stent use. Stents can result in reflux (backflow of urine along the ureter), which will promote recurrent urinary infection and possible renal parenchymal damage. Furthermore, long-term stent use is associated with infection and precipitation of salts from the urine, which can lead to a build-up of crystalline deposits on the stent surface, making stent removal difficult and painful. This paper examines factors governing urine flow in a stented ureter, the implications for reflux, and the processes by which the stent surface encrusts, in particular focusing on the influence of bacterial infection. An interdisciplinary approach is adopted, involving a combination of theoretical investigations and novel experiments.

On the role of the starved codon and the takeoff site in ribosome bypassing in Escherichia coli.

Translating ribosomes can skip over stretches of messenger RNA and resume protein chain elongation after a "bypassed" region. We have previously shown that limitation for isoleucyl-tRNA can initiate a ribosome bypass when an AUA codon is in the ribosomal A-site. We have now generalized this effect to other "hungry" codons calling for four different limiting aminoacyl-tRNA species, suggesting that a pause at any A-site will have this effect. We have assessed bypassing in a large family of reporters with nearly every different triplet in the "takeoff site", i.e. the P-site on the 5' side of the hungry codon, and an identical "landing site" codon 16 nucleotides downstream. The different takeoff sites vary over a factor of 50 in bypassing proficiency. At least part of this variation appears to reflect stability of the codon Colon, two colons anticodon interaction at the takeoff site, as indicated by the following: (a) the bypassing proficiency of different tRNAs shows a rough correlation with the frequency of A Colon, two colons U as opposed to G Colon, two colons C pairs in the codon Colon, two colons anticodon association; (b) specific tRNAs bypass more frequently from codons ending in U than from their synonym ending in C; (c) an arginine tRNA with Inosine in the wobble position which reads CGU, CGC, and CGA bypasses much more frequently from the last codon than the first two synonyms.

Neuropsychological function in Gulf War veterans: relationships to self-reported toxicant exposures.

BACKGROUND: The present study was aimed at (1) exploring evidence of central nervous system (CNS) dysfunction among Gulf War (GW) veterans on neuropsychological tests and (2) examining whether performance on neuropsychological tests was related to specific neurotoxicant exposures experienced in the Gulf. METHODS: The GW-deployed groups were selected using stratified random sampling methods from two distinct cohorts of GW veterans. A comparison group that had been called up for GW service but deployed to Germany rather than the Gulf also was examined. Neuropsychological function was assessed using a pre-determined battery chosen to include tests known to be highly sensitive to the behavioral effects of the neurotoxicants thought to have been present in the Gulf. RESULTS: Self-reported exposures were related to neuropsychological test performance controlling for post-traumatic stress disorder, major depression, and other known covariates of neuropsychological test performance. Results showed that GW-deployed veterans performed more poorly than the Germany-deployed veterans on several specific neuropsychological tests, but after adjustment for multiple comparisons, only the differences in mood complaints remained significant. Within the GW-deployed group, self-reported exposure to chemical warfare agents was associated with poorer performance on cognitive tests involving specific functional domains. CONCLUSIONS: Results provide evidence that there are subtle differences in CNS function among GW-deployed veterans who report chemical warfare agent exposure while in the GW theater.

Deuterium/hydrogen isotope ratio measurement of water and organic samples by continuous-flow isotope ratio mass spectrometry using chromium as the reducing agent in an elemental analyser.

A rapid continuous-flow technique for quantitative determination of hydrogen isotope ratios in water and organic materials at natural abundance levels is described. Water and organic samples were reduced in a helium stream at temperatures in excess of 1000 degrees C over chromium metal. delta(2)H per thousand values of water and organic samples were determined by calibration against International Atomic Energy Agency reference materials V-SMOW and SLAP water. The accuracy of the method was demonstrated through the analysis of the intermediate water standard GISP and IAEA water intercomparison materials OH-1, OH-2 and OH-3. Values obtained using this technique compared well with reference values (maximum difference 2.2 per thousand). The precision of water analyses was less than 2.3 per thousand (1 sigma or 1 standard deviation) in all cases. No apparent memory effect was observed when measuring samples at the natural abundance level. The application of the technique to organic molecules and the salts of organic acids was successfully demonstrated by measuring the delta(2)H per thousand values of an n-hexadecane laboratory reference and anhydrous calcium formate versus water calibration materials.

Chemical sensitivity and chronic fatigue in Gulf War veterans: a brief report.

The foci of this brief report are to (1) describe the prevalence of chemical sensitivity (CS) and chronic fatigue (CF) symptomatology and of presumptive multiple CS and CF syndrome diagnoses, and (2) explore the potential overlap between one purported case definition (i.e., chronic multi-symptom illness) and these unexplained symptom syndromes in a well-characterized group of Gulf War veterans. The number of subjects with CS and CF symptomatology and presumptive multiple CS and CF syndrome diagnoses was higher in the Gulf War-deployed group compared with a group deployed to Germany during the Gulf War. However, the percent differences were not significant when comparing the presumptive diagnoses of multiple CS and CF syndrome. The characteristic differences between the groups and the overlap with chronic multi-symptom illness are also discussed.

Feasibility of using GFP-expressing Escherichia coli, coupled with fluorimetry, to determine protozoan ingestion rates.

The feasibility of using a live Escherichia coli population, which had been engineered to express the green fluorescent protein (GFP), coupled with fluorimetry, was tested as a means for determining protozoan ingestion rates. Its potential use was based on evidence that once cells are acidified, e.g. in a food vacuole, the fluorescence is lost. Of the 29 protozoa tested, over 85% ingested the GFP-expressing E. coli and a detailed experiment with the ciliate Tetrahymena pyriformis was carried out, principally to assess the performance of the live bacterium against two commonly used surrogate prey, i.e. fluorescently labelled bacteria (FLB) and fluorescently labelled microspheres (FLMs). A decrease in GFP-expressing E. coli fluorescence and, hence, concentration, was recorded by fluorimetry and epifluorescence microscopy, with calculated ingestion rates being equivalent. A higher ingestion rate was determined by counting the number of fluorescent E. coli within the ciliate over 120 s, but this was equivalent to that obtained for the stained E. coli using the same direct method of analysis. However, the ciliate was shown to process the stained and unstained E. coli cells differently, with only the latter resulting in an increase in ciliate abundance.

Ursodeoxycholic acid alone or with chenodeoxycholic acid for dissolution of cholesterol gallstones: a randomized multicentre trial. The British-Italian Gallstone Study group.

BACKGROUND: Combination therapy using ursodeoxycholic acid plus chenodeoxycholic acid has been advocated for dissolution of cholesterol gallstones because the two bile acids have complementary effects on biliary lipid metabolism and cholesterol solubilization. AIM: To compare the clinical efficacy of combination therapy with ursodeoxycholic acid monotherapy. PATIENTS AND METHODS: A total of 154 symptomatic patients with radiolucent stones (< or = 15 mm) in functioning gallbladders were enrolled from six centres in England and Italy. They were randomized to either a combination of chenodeoxycholic acid plus ursodeoxycholic acid (5 mg.day/kg each) or to ursodeoxycholic acid alone (10 mg.day/kg). Dissolution was assessed by 6-monthly oral cholecystography and ultrasonography for up to 24 months. RESULTS: Both regimens reduced the frequency of biliary pain and there was no significant difference between them in terms of side-effects or dropout rate. Complete gallstone dissolution on an intention-to-treat basis was similar at all time intervals. At 24 months this was 28% with ursodeoxycholic acid alone and 30% with combination therapy. The mean dissolution rates at 6 and 12 months were 47% and 59% with ursodeoxycholic acid, and 44% and 59% with combination therapy, respectively. CONCLUSION: There is no substantial difference in the efficacy of combined ursodeoxycholic acid and chenodeoxycholic acid and that of ursodeoxycholic acid alone in terms of gallstone dissolution rate, complete gallstone dissolution, or relief of biliary pain.

Distribution of tyrosine hydroxylase-containing neurons and fibers in the brain of the budgerigar (Melopsittacus undulatus): general patterns and labeling in vocal control nuclei.

The distribution of tyrosine hydroxylase (TH) was mapped out in cells and fibers of the budgerigar (Melopsittacus undulatus) brain. Special attention was given to vocal control and auditory nuclei because budgerigars are a psittacine species in which both males and females are capable of lifelong vocal learning (Farabaugh et al. [1994] J. Comp. Psychol 108:81-92). The results show that TH staining in the central nucleus of the anterior archistriatum (AAc) resembled that of surrounding archistriatal fields, except for portions of the ventral archistriatum, which exhibited substantially more TH+ fibers. Fewer fibers and fiber baskets are present in the central nucleus of the lateral neostriatum (NLc) than in surrounding fields. Both the oval nuclei of the ventral hyperstriatum (HVo) and anterior neostriatum (NAo) exhibit less fiber staining than surrounding fields whereas fiber staining in the medial NAo (NAom) and magnicellular nucleus of the parolfactory lobe (LPOm) resemble that of surrounding fields. Staining in primary telencephalic auditory nuclei was extremely low. The only sex difference observed was slightly increased TH staining in LPOm of females compared with surrounding fields on some tissue sections. These findings are in contrast to previous findings in zebra finch (Poephila guttata), a close ended vocal learning songbird in which TH staining in vocal nuclei increases during development and remains greater than surrounding fields throughout adulthood. The present results therefore support the view that catecholamines act to inhibit vocal plasticity in adult vocal learning species. Several unique features of TH-immunoreactive (ir) cell groups were observed in the brainstem including sparsely scattered TH-ir somata immediately adjacent to the third ventricle, within the tectum, basal forebrain, archistriatum, and caudal neostriatum, and in the hippocampus. These latter populations have not been described in other avian species and resemble features of the catecholamine system generally found in either reptiles or mammals.

Local-regional control in breast cancer patients with a possible genetic predisposition.

PURPOSE: Local control rates for breast cancer in genetically predisposed women are poorly defined. Because such a small percentage of breast cancer patients have proven germline mutations, surrogates, such as a family history for breast cancer, have been used to examine this issue. The purpose of this study was to evaluate local-regional control following breast conservation therapy (BCT) in patients with bilateral breast cancer and a breast cancer family history. METHODS AND MATERIALS: We retrospectively reviewed records of all 58 patients with bilateral breast cancer and a breast cancer family history treated in our institution between 1959 and 1998. The primary surgical treatment was a breast-conserving procedure in 55 of the 116 breast cancer cases and a mastectomy in 61. The median follow-up was 68 months for the BCT patients and 57 months for the mastectomy-treated patients. RESULTS: Eight local-regional recurrences occurred in the 55 cases treated with BCT, resulting in 5- and 10-year actuarial local-regional control rates of 86% and 76%, respectively. In the nine cases that did not receive radiation as a component of their BCT, four developed local-regional recurrences (5- and 10-year local-regional control rates of BCT without radiation: 49% and 49%). The 5- and 10-year actuarial local-regional control rates for the 46 cases treated with BCT and radiation were 94% and 83%, respectively. In these cases, there were two late local recurrences, developing at 8 years and 9 years, respectively. A log rank comparison of radiation versus no radiation actuarial data was significant at p = 0.009. In the cases treated with BCT, a multivariate analysis of radiation use, patient age, degree of family history, margin status, and stage revealed that only the use of radiation was associated with improved local control (Cox regression analysis p = 0.021). The 10-year actuarial rates of local-regional control following mastectomy with and without radiation were 91% and 89%, respectively. CONCLUSIONS: Patients with a possible genetic predisposition to breast cancer had low 5-year rates of local recurrence when treated with breast conserving surgery and radiation, but the local failure rate exceeded 50% when radiation was omitted. Our data are consistent with the hypothesis that patients with an underlying genetic predisposition develop cancers with radiosensitive phenotypes.

Effect of thalidomide on gastrointestinal toxic effects of irinotecan.

Irinotecan is the only accepted second-line treatment for colorectal cancer in the USA. Doses are, however, frequently limited by associated late-onset diarrhoea. Thalidomide has antiangiogenic and immunomodulatory properties and is being investigated as an antineoplastic. We did a pilot study of combination therapy with thalidomide and irinotecan for metastatic colorectal cancer. In an interim analysis of nine patients, thalidomide had almost eliminated the dose-limiting gastrointestinal toxic effects of irinotecan, especially diarrhoea and nausea (each p<0.0001), and eight of nine patients were able to complete the chemotherapy course.

Review article: epidemiology of gall-bladder disease--role of intestinal transit.

Recent epidemiological studies have suggested that hyperinsulinaemia may be a central factor in the pathogenesis of cholesterol gallstones, explaining a probable link with physical inactivity as well as abdominal adiposity. There is also increasing evidence for the hypothesis that enrichment of bile with DCA. 'the colonic bile acid', leads to enrichment of bile with cholesterol. Biliary DCA can be raised and lowered by slowing down and speeding up colonic transit, respectively. Slow transit is characteristic of non-obese British women with gallstones and of non-obese peasants in a gallstone-prone mountain community. High biliary DCA predicts recurrence of gallstones and so does laxative usage, a pointer to constipation and therefore to slow transit. In some studies, at least, a high fibre intake is protective against gallstones. Much else besides fibre influences colonic function. Future studies of gallstone aetiology should include measurements of colonic function. Measures that speed up colonic transit should be tested for their ability to prevent gallstone formation in high-risk individuals.

Risk factors for the development of gallstone recurrence following medical dissolution. The British-Italian Gallstone Study Group.

OBJECTIVE: To assess risk factors for gallstone recurrence following non-surgical treatment. DESIGN: A prospective follow-up of a multicentre cohort of post-dissolution gallstone patients. SETTING: Six gastroenterology units in the UK and Italy. PARTICIPANTS: One hundred and sixty-three patients with confirmed gallstone dissolution following non-surgical therapy (bile acids or lithotripsy plus bile acids), followed up by ultrasound scan and clinical assessment at 6-monthly intervals for up to 6 years (median, 25 months; range, 6-70 months). OUTCOME MEASURES: Subject-related variables (sex, age, height, weight, body mass index), gallstone-related variables (number, diameter, presence of symptoms, months to complete stone clearance), treatment modalities (bile acid therapy, extracorporeal shock wave lithotripsy) and follow-up related variables (weight change, use of non-steroidal anti-inflammatory agents, statins, pregnancies and/or use of oestrogens) were assessed by univariate and multivariate analysis as putative risk factors for gallstone recurrence. RESULTS: Forty-five gallstone recurrences were observed during the follow-up period. Multiple primary gallstones and length of time to achieve gallstone dissolution were the only variables associated with a significant increase in the recurrence rate. Appearance of biliary sludge during follow-up was also significantly related to development of gallstone recurrence. Use of statins or non-steroidal anti-inflammatory agents did not confer protection against recurrence. CONCLUSIONS: Patients with primary single stones are the best candidates for non-surgical treatment of gallstones, because of a low risk of gallstone recurrence. The positive association of recurrence with biliary sludge formation and time to dissolution of primary stones may provide indirect confirmation for the role of impaired gallbladder motility in the pathogenesis of this condition.

Central venous catheter placement in patients with disorders of hemostasis.

BACKGROUND: Patients requiring central venous access frequently have disorders of hemostasis. The aim of this study was to identify factors predictive of bleeding complications after central venous catheterization in this group of patients. METHODS: A retrospective analysis of all central venous catheters placed over a 2-year period (1997 to 1999) at our institution were performed. The age, sex, clinical diagnosis, most recent platelet count, prothrombin international normalized ratio (INR), activated partial thromboplastin time (aPTT), catheter type, the number of passes to complete the procedure, and bleeding complications were retrieved from the medical records. RESULTS: In a 2-year period, 2,010 central venous catheters were placed in 1,825 patients. Three hundred and thirty placements were in patients with disorders of hemostasis. In 88 of the 330 patients, the underlying coagulopathy was not corrected before catheter placement. In these patients, there were 3 bleeding complications requiring placement of a purse string suture at the catheter entry site. In the remaining 242 patients, there was 1 bleeding complication. Of the variables analyzed, only a low platelet count (<50 x 10(9)/L) was significantly associated with bleeding complications. CONCLUSION: Central venous access procedures can be safely performed in patients with underlying disorders of hemostasis. Even patients with low platelet counts have infrequent (3 of 88) bleeding complications, and these problems are easily managed.