Heat treatment of bovine colostrum. I: effects of temperature on viscosity and immunoglobulin G level

The objective of this study was to identify the critical temperature, at or below which heat-treatment of bovine colostrum would produce no significant changes in viscosity, IgG concentration, or Ig activity. Results of preliminary work, using a Rapid Visco Analyzer (RVA) to heat 50-mL aliquots from 6 unique batches of bovine colostrum at 59, 60, 61, 62, and 63 degrees C, suggested that colostrum could be heated to 60 degrees C for up to 120 min without changing viscosity or IgG concentration. This finding was confirmed by heating 50-mL aliquots from 30 unique batches of colostrum in an RVA for 120 min at 60 and 63 degrees C. Heating colostrum to 63 degrees C resulted in an estimated 34% decrease in IgG concentration and 33% increase in viscosity. However, there was no difference in IgG concentration between preheat-treated (73.4 +/- 26.5 mg/mL) and post-heat-treated (74.5 +/- 24.3 mg/mL) samples after heating colostrum to 60 degrees C in an RVA for 120 min. Similarly, viscosity was unaffected after heating colostrum to 60 degrees C in an RVA for 120 min. High quality colostrum (> or =73.0 mg/mL) suffered greater losses of IgG and greater viscosity changes when heated to 63 degrees C than did moderate quality colostrum (<73.0 mg/mL). However, the effects of colostrum quality were minor if high quality colostrum was only heated to 60 degrees C. The results of a bovine viral diarrhea serum neutralization assay suggested that antibody activity was unchanged after heating colostrum to either 60 or 63 degrees C. However, these results were interpreted as being inconclusive due to a high proportion of missing results because of the congealing of many samples after heat treatment. The results of this study indicate that 50-mL volumes of bovine colostrum can be heat treated at 60 degrees C for up to 120 min in an RVA without affecting IgG concentration or viscosity.

A phase II trial of ZD6474 in patients with hereditary metastatic medullary thyroid cancer

5533

Background: Medullary thyroid carcinoma (MTC) is the most common cause of death in patients with hereditary syndromes caused by specific mutations in the RET protooncogene. RET activation is the oncogenic event, which results in intrinsic RET receptor tyrosine kinase activity, but other pathways, such as VEGFR- and EGFR-dependent signaling, also participate in tumor growth and development. ZD6474 is a once-daily oral agent that selectively targets RET, VEGFR and EGFR tyrosine kinases. The clinical activity of ZD6474 was evaluated in patients with hereditary MTC. Methods: In this open-label Phase II study, patients with unresectable, measurable, locally advanced or metastatic hereditary MTC and a RET germline mutation received once-daily oral doses of ZD6474 300 mg. The primary objective was to assess the objective tumor response (RECIST). Secondary objectives included assessments of biochemical response (determined by changes in plasma levels of calcitonin [CTN]) and safety/tolerability of ZD6474. An exploratory objective was to measure plasma levels of carcinoembryonic antigen (CEA). Results: As of 30 November 2005, 16 patients (6 male/10 female; median age 50 years, range 22–77) had entered the study and received initial treatment with ZD6474 300mg. The median duration of treatment was 136 days (range 16–353). Fifteen patients were evaluable for tumor response, CTN, and CEA. Objective tumor assessments have demonstrated partial responses in 3 patients (n = 2 confirmed; n = 1 unconfirmed), stable disease in 10 patients (n = 8, ≥8 and <24 weeks; n = 2, ≥24 weeks) and progressive disease in 2 patients. A >50% decrease from baseline in plasma CTN levels has been maintained for at least 4 weeks in 12/15 patients; a decrease in plasma CEA levels of the same magnitude and duration has been observed in 6/15 patients. Common adverse events (AEs) were diarrhea (n = 12) and nausea, rash and fatigue (each n = 11). CTC grade 3 AEs attributable to ZD6474 were QTc interval prolongation (n = 3), and diarrhea, skin rash and hypertension (each n = 2). Conclusions: ZD6474 shows promising evidence of clinical activity in patients with hereditary MTC. These are preliminary data and patients are still being recruited to this ongoing study.

[Table: see text]

Measurement of the electric form factor of the neutron at Q2=0.5 and 1.0 GeV2/c2

The electric form factor of the neutron was determined from measurements of the d-->(e-->,e'n)p reaction for quasielastic kinematics. Polarized electrons were scattered off a polarized deuterated ammonia (15ND3) target in which the deuteron polarization was perpendicular to the momentum transfer. The scattered electrons were detected in a magnetic spectrometer in coincidence with neutrons in a large solid angle detector. We find G(n)(E)=0.0526+/-0.0033(stat)+/-0.0026(sys) and 0.0454+/-0.0054+/-0.0037 at Q(2)=0.5 and 1.0 (GeV/c)(2), respectively.

Can patients with osteoporosis, who should benefit from implementation of the national service framework for older people, be identified from general practice computer records? A pilot study that illustrates the variability of computerized medical records and problems with searching them

Although UK general practice is highly computerized, comprehensive use of these computers is often limited to registration data and the issue of repeat prescriptions. The recording of diagnostic data is patchy. This study examines whether patients with, or at risk of, osteoporosis can be readily identified from general practice computer records. It reports the findings of a pilot study designed to show the variability of recording the diagnosis of osteoporosis and osteopenia, as well as how useful surrogate markers might be to identify these patients. The study also illustrates the difficulties that even skilled practitioners in a primary care research network experience in extracting clinical data from practice information systems. Computer searches were carried out across six practices in a general practice research network in the south-east of England. Two of these practices had previously undertaken research projects in osteoporosis and were consequently expected to have excellent data quality in osteoporosis. These two practices had a combined list size of 27,500 and the remaining practices had a combined practice population of 43,000 patients. The data were found to be variable with over 10-fold differences between practices in the recorded prevalence of osteoporosis diagnosis as well as its surrogate markers-such as fragility fractures, long-term steroid prescription, etc. There was no difference in data quality between the two practices that had conducted osteoporosis research and the rest of the group, other than in the areas of diagnostic recording and prescribing for osteoporosis and recording of fractures. Issues were raised by the practices that struggled to identify patients at risk of osteoporosis about the limitations of Read classification in this disease area. Practices need further assistance if the patients at risk are to be identified. Without urgent action, it will be difficult for practices to identify the patients who are likely to benefit from Standard 6-'Falls' of the National Service Framework for Older People. These findings also have broader implications as UK general practice moves towards the implementation of a quality-based contract.

The Effect of Eicosapentaenoic Acid on Rat Lymphocyte Proliferation Depends Upon Its Position in Dietary Triacylglycerols

Animal and human studies have shown that greatly increasing the amount of fish oil [rich in long-chain (n-3) PUFA] in the diet can decrease lymphocyte functions. The effects of a more modest provision of long-chain (n-3) PUFA and whether eicosapentaenoic acid (20:5) and docosahexaenoic acid (22:6) have the same effects as one another are unclear. Whether the position of 20:5 or 22:6 in dietary triacylglycerols (TAG) influences their incorporation into immune cells and their subsequent functional effects is not known. In this study, male weanling rats were fed for 6 wk one of 9 diets that contained 178 g lipid/kg and that differed in the type of (n-3) PUFA and in the position of these in dietary TAG. The control diet contained 4.4 g alpha-linolenic acid (18:3)/100 g total fatty acids. In the other diets, 20:5 or 22:6 replaced a portion (50 or 100%) of 18:3, and were in the sn-2 or the sn-1(3) position of dietary TAG. There were significant dose-dependent increases in the proportion of 20:5 or 22:6 in spleen mononuclear cell phospholipids when 20:5 or 22:6 was fed. These increases were at the expense of arachidonic acid and were largely independent of the position of 20:5 or 22:6 in dietary TAG. Spleen lymphocyte proliferation increased dose dependently when 20:5 was fed in the sn-1(3) position of dietary TAG. There were no significant differences in interleukin-2, interferon-gamma or interleukin-10 production among spleen cells from rats fed the different diets. Prostaglandin E(2) production by spleen mononuclear cells was decreased by inclusion of either 20:5 or 22:6 in the diet in the sn-1(3) position. Thus, incorporation of 20:5 or 22:6 into spleen mononuclear cell phospholipids is not influenced by the position in dietary TAG. However, the pattern of incorporation may be influenced, and there are some differential functional effects of the position of long-chain (n-3) PUFA in dietary TAG. A moderate increase in the intake of 20:5 at the sn-1(3) position of dietary TAG increases lymphocyte proliferation.

Measurements of GnE/GnM from the 2H(e-->,en-->)1H Reaction to Q2=1.45 (GeV/c)2

We report new measurements of the ratio of the electric form factor to the magnetic form factor of the neutron, G(n)(E)/G(n)(M), obtained via recoil polarimetry from the quasielastic 2H(e-->,e(')n-->)1H reaction at Q2 values of 0.45, 1.13, and 1.45 (GeV/c)(2) with relative statistical uncertainties of 7.6% and 8.4% at the two higher Q2 points, which points have never been achieved in polarization measurements.

High resolution spectroscopy of the 12Lambda B hypernucleus produced by the (e,e'K+) reaction

High-energy, cw electron beams at new accelerator facilities allow electromagnetic production and precision study of hypernuclear structure, and we report here on the first experiment demonstrating the potential of the (e,e'K+) reaction for hypernuclear spectroscopy. This experiment is also the first to take advantage of the enhanced virtual photon flux available when electrons are scattered at approximately zero degrees. The observed energy resolution was found to be approximately 900 keV for the (12)(Lambda)B spectrum, and is substantially better than any previous hypernuclear experiment using magnetic spectrometers. The positions of the major excitations are found to be in agreement with a theoretical prediction and with a previous binding energy measurement, but additional structure is also observed in the core excited region, underlining the future promise of this technique.

In vivo gene transfer studies on the regulation and function of the vasopressin and oxytocin genes

Novel genes can be introduced into the germline of rats and mice by microinjecting fertilized one-cell eggs with fragments of cloned DNA. A gene sequence can thus be studied within the physiological integrity of the resulting transgenic animals, without any prior knowledge of its regulation and function. These technologies have been used to elucidate the mechanisms by which the expression of the two genes in the locus that codes for the neuropeptides vasopressin and oxytocin is confined to, and regulated physiologically within, specific groups of neurones in the hypothalamus. A number of groups have described transgenes, derived from racine, murine and bovine sources, in both rat and mouse hosts, that mimic the appropriate expression of the endogenous vasopressin and genes in magnocellular neurones (MCNs) of the supraoptic and paraventricular nuclei. However, despite considerable effort, a full description of the cis-acting sequences mediating the regulation of the vasopressin-oxytocin locus remains elusive. Two general conclusions have nonetheless been reached. First, that the proximal promoters of both genes are unable to confer any cell-specific regulatory controls. Second, that sequences downstream of the promoter, within the structural gene and/or the intergenic region that separates the two genes, are crucial for appropriate expression. Despite these limitations, sufficient knowledge has been garnered to specifically direct the expression of reporter genes to vasopressin and oxytocin MCNs. Further, it has been shown that reporter proteins can be directed to the regulated secretory pathway, from where they are subject to appropriate physiological release. The use of MCN expression vectors will thus enable the study of the physiology of these neurones through the targeted expression of biologically active molecules. However, the germline transgenic approach has a number of limitations involving the interpretation of phenotypes, as well as the large cost, labour and time demands. High-throughput somatic gene transfer techniques, principally involving the stereotaxic injection of hypothalamic neuronal groups with replication-deficient adenoviral vectors, are now being developed that obviate these difficulties, and which enable the robust, long-lasting expression of biologically active proteins in vasopressin and oxytocin MCNs.

Further delineation of the sequences required for the expression and physiological regulation of the vasopressin gene in transgenic rat hypothalamic magnocellular neurones

We have introduced transgenes into rats with a view to defining genomic regions that mediate the cell-specific and physiological regulation of the vasopressin gene. These transgenes consist of the rat vasopressin structural gene with a reporter inserted into exon III, flanked by different lengths of upstream and downstream sequences. 11-VCAT-3 is flanked by 11 kbp of upstream sequences and 3 kbp of downstream sequences. The previously described 5-VCAT-3 is flanked by 5 kbp of upstream and 3 kbp of downstream sequences. 3-VCAT-3 has 3 kbp of upstream and 3 kbp of downstream sequences, and 3-VCAT-0.2 is flanked by 3 kbp of upstream and 0.2 kbp of downstream sequences. All four transgenes elicit the same expression patterns; low basal expression is seen in the magnocellular supraoptic and paraventricular nuclei, and is negligible in the suprachiasmatic nucleus. Expression increases markedly in vasopressin magnocellular cells following dehydration. The sequences responsible for the cell-specific expression and physiological regulation of our transgenes thus reside within the confines of the smallest construct studied, 3-VCAT-0.2.

The use of a new continuous wireless cardiorespiratory telemonitoring system by elderly patients at home

The diagnosis and management of increasing numbers of patients with chronic diseases in the community require new technologies and strategies of care. We have used a new wireless cardiorespiratory telemonitoring system to monitor 14 elderly patients with a variety of chronic diseases at home. The electrocardiogram (ECG), heart rate and variability, and breathing were recorded on two separate occasions for 24 h. There was no difference in the data recorded when a research nurse applied the monitoring system and when the patients applied it themselves. The ECG and heart rate were recorded for 98% of the monitored time, and the frequency and periodicities of breathing were recorded for 74% and 61% of sleep and rest time by visual and automatic analysis, respectively. The results show that 24 h activity and cardiorespiratory telemonitoring can be performed by elderly patients at home. Significant unsuspected abnormalities of breathing and heart rhythm, amenable to treatment, were also detected.

Compliance and effectiveness of 1 year's home telemonitoring. The report of a pilot study of patients with chronic heart failure

Patients with a diagnosis of heart failure, registered at the study practice, were recruited into the study. First, they had a cardiologist's assessment. They were then randomised into telemonitored patients who measured pulse, BP, weight and video consulted, and controls.

AIM

To examine the acceptability, effectiveness and reliability of home telemonitoring.

RESULTS

A high proportion of those invited took part (n=20/24). Compliance with measuring weight, pulse and BP remained high throughout the study. The data collection system and secure web-server were reliable. The telemonitoring group complied better with collecting prescriptions for their cardiac drugs. Video consulting started with enthusiasm, but became less useful. There were no significant differences in the quality of life (GHQ) and Chronic Heart Failure (Guyatt) questionnaire scores between the telemonitored group and the controls.

CONCLUSIONS

Home telemonitoring is an acceptable reliable intervention. Baseline rates for compliance with self-monitoring are set out in this study. Benefit in terms of compliance with medication and self-monitoring is still seen after 1 year. Video consulting over ordinary telephone lines did not show sustained benefit, and was not complied with.

Reducing recurrence in child protective services: impact of a targeted safety protocol

Statewide implementation of a child safety assessment protocol by the Illinois Department of Children and Family Services (DCFS) in 1995 is assessed to determine its impact on near-term recurrence of child maltreatment. Literature on the use of risk and safety assessment as a decision-making tool supports the DCFS's approach. The literature on the use of recurrence as a summative measure for evaluation is described. Survival analysis is used with an administrative data set of 400,000 children reported to DCFS between October 1994 and November 1997. An ex-post facto design tests the hypothesis that the use of the protocol cannot be ruled out as an explanation for the observed decline in recurrence following implementation. Several alternative hypotheses are tested: change in use of protective custody, other concurrent changes in state policy, and the concurrent experience of other states. The impact of the protocol to reduce recurrence was not ruled out.

Longitudinal changes in bone lead concentration: implications for modelling of human bone lead metabolism

In this study, 539 occupationally exposed subjects received in vivo bone lead measurements using 109Cd excited K X-ray fluorescence (109Cd K XRF). Of these subjects, 327 had previously been measured five years earlier. Measurements were made from both tibia and calcaneus samples, taken to reflect cortical and trabecular bone, respectively. Changes in tibia lead concentration related negatively to initial tibia lead concentration and positively to both lead exposure between the measurement dates and initial calcaneus lead concentration. This finding confirmed and strengthened the interpretation of an earlier study involving fewer subjects. With the larger data set it was possible to examine subgroups of subjects. This showed that people aged less than 40 years had a shorter half-life for the release of lead from the tibia (4.9, 95% CI 3.6-7.8 years) than did those older than 40 (13.8, 95% CI 9.7-23.8 years). Similarly, less intensely exposed subjects (lifetime average blood lead < or = 25 micrograms dL-1) had a shorter tibia lead half-life (6.2, 95% CI 4.7-9.0 years) than those with a lifetime average blood lead > 25 micrograms dL-1 (14.7, 95% CI 9.7-29.9 years). Age and measures of lead exposure were strongly correlated; nevertheless, age matched subgroups with high and low intensity exposures showed clearance rates that were significantly different at the 10% level, with the lower exposure intensity again being associated with the faster clearance. These findings imply that current models of human lead metabolism should be examined with a view to adjusting them to account for kinetic rates varying with age and probably also with exposure level.

Production of transgenic rodents by the microinjection of cloned DNA into fertilized one-cell eggs

Transgenic technologies that enable rapid movement between genotype and phenotype through specific loss-of-function, overexpression, or misexpression phenotypes will be crucial in the elucidation of gene sequences emerging from genome projects. This article describes detailed procedures for the generation of transgenic mice and rats by the injection of cloned DNA into the pronuclei of fertilized one-cell eggs.

Gene transfer strategies for the physiologist

Foreign genes can be introduced into whole animals using methods of germline transgenesis and somatic gene delivery. While germline transgenesis can generate useful animal models for genetic studies, it can be costly, time-consuming and requires the use of a large number of animals. An alternative means of gene transfer is to deliver genes to somatic cells using non-viral and viral technologies. Non-viral methods such as naked DNA injection, electroporation and liposome/cation lipid-mediated gene transfer are relatively inefficient. In contrast, viruses are effective vehicles that carry foreign genes into a cell rapidly and efficiently. Here we illustrate the usefulness of adenoviral vectors to express a potent and specific inhibitor of cAMP-dependent protein kinase (PKA) to study the role of cyclic 3',5'-cyclic AMP (cAMP) in the osmotic regulation of the vasopressin gene in a transgenic rat model. The ability to modify endogenous systems within specific cells in a whole animal model allows gene effects to be studied with physiological relevance. The combination of molecular biology and integrative physiology is a powerful application that can aid in the elucidation of how gene function can translate into complex systems in an organism.

Alcohol-related aggression in the general population

OBJECTIVE

This study estimates the relationships between drinking in the event and drinking patterns and different levels of aggression severity.

METHOD

A telephone survey of 1,001 adults (542 women) age 18 and over was conducted (response rate of 67%) using computer assisted telephone interviewing (CATI). Respondents were asked whether they had been personally involved in a serious argument, an incident involving threat, or physical aggression in the past year and whether anyone had been drinking alcohol in the most recent incident. Respondents also reported their typical alcohol consumption patterns.

RESULTS

The proportion of respondents reporting involvement in serious arguments, threats or physical aggression was 19.8%, 11.8% and 12.0%, respectively. Someone in the incident had been drinking in 38.1% of serious arguments, 56.5% of threats and 67.9% of incidents of physical aggression. When gender, age, education, marital status and employment status were controlled for, high quantity drinking (as measured by the largest number of drinks consumed on one drinking occasion in the past year), overall estimated annual volume of alcohol consumed, and frequency of consuming five drinks per occasion were significantly greater for physical aggression, compared with arguments and no aggression. However, drinker status (abstainer/drinker) and frequency of drinking were not significantly associated with involvement in aggression. In a logistic regression analysis controlling for demographic variables, a composite measure of alcohol consumption was highly significant for physical aggression versus no aggression and for physical versus verbal aggression. Physical aggression was also associated with being younger, separated/ divorced and a student.

CONCLUSIONS

The results suggest that alcohol intoxication, rather than mere alcohol consumption, is associated with aggression. Moreover, alcohol intoxication is more strongly associated with physical aggression than with verbal aggression.