Effects of time on feed and post-mortem aging on palatability and lipid composition of crossbred Wagyu beef

Twenty-seven Wagyu-sired steers were fed for 90 (14 steers) or 170 (13 steers) days to study the effects of time on feed on palatability and fatty acid composition, and the effects of post-mortem aging time (2, 4 or 10 days) on palatability. Hot carcass weight, fat thickness, longissimus dorsi muscle area, yield grade, estimated kidney, pelvic and heart fat and maturity score were increased (p < 0.05) by an additional 80 days on the high concentrate feed, but marbling was not changed (p > 0.05). Feeding the high concentrate diet for 170 days increased Warner-Bratzler shear force values (p < 0.05) and tended to decrease tenderness (p > 0.05), flavor intensity and connective tissue scores. For the 90 day feeding group, 4 days of aging improved connective tissue score (p < 0.05) and tended to increase (p > 0.05) tenderness scores and decrease shear force, compared with 2 days of aging. For the 170 day feeding group, 10 days of aging improved (p < 0.05) shear force and all sensory attributes except flavor intensity, compared to 2 days of aging. An additional 80 days on feed decreased (p < 0.05) stearic acid and total saturated fatty acids (SFA) and generally increased (p < 0.05) monounsaturated fatty acids (MUFA), polyunsaturated fatty acids (PUFA), MUFA:SFA, and PUFA:SFA in subcutaneous fat and longissimus dorsi muscle. The cholesterol content of fat and muscle increased (p < 0.05) as time on feed increased. Ninety days on a high concentrate diet was adequate for yearling crossbred Wagyu steers to produce highly acceptable carcasses. The additional 80 days on feed produced little or no overall benefit and the steers became overfinished and less tender. Ten days post-mortem aging improved (p < 0.05) all palatability attributes except flavor intensity.

Quality of life in haemophilia A: Hemophilia Utilization Group Study Va (HUGS-Va)

This study describes health-related quality of life (HRQoL) of persons with haemophilia A in the United States (US) and determines associations between self-reported joint pain, motion limitation and clinically evaluated joint range of motion (ROM), and between HRQoL and ROM. As part of a 2-year cohort study, we collected baseline HRQoL using the SF-12 (adults) and PedsQL (children), along with self-ratings of joint pain and motion limitation, in persons with factor VIII deficiency recruited from six Haemophilia Treatment Centres (HTCs) in geographically diverse regions of the US. Clinically measured joint ROM measurements were collected from medical charts of a subset of participants. Adults (N = 156, mean age: 33.5 ± 12.6 years) had mean physical and mental component scores of 43.4 ± 10.7 and 50.9 ± 10.1, respectively. Children (N = 164, mean age: 9.7 ± 4.5 years) had mean total PedsQL, physical functioning, and psychosocial health scores of 85.9 ± 13.8, 89.5 ± 15.2, and 84.1 ± 15.3, respectively. Persons with more severe haemophilia and higher self-reported joint pain and motion limitation had poorer scores, particularly in the physical aspects of HRQoL. In adults, significant correlations (P < 0.01) were found between ROM measures and both self-reported measures. Except among those with severe disease, children and adults with haemophilia have HRQoL scores comparable with those of the healthy US population. The physical aspects of HRQoL in both adults and children with haemophilia A in the US decrease with increasing severity of illness. However, scores for mental aspects of HRQoL do not differ between severity groups. These findings are comparable with those from studies in European and Canadian haemophilia populations.

The relationship between ADHD and key cognitive phenotypes is not mediated by shared familial effects with IQ

BACKGROUND

Twin and sibling studies have identified specific cognitive phenotypes that may mediate the association between genes and the clinical symptoms of attention deficit hyperactivity disorder (ADHD). ADHD is also associated with lower IQ scores. We aimed to investigate whether the familial association between measures of cognitive performance and the clinical diagnosis of ADHD is mediated through shared familial influences with IQ.

METHOD

Multivariate familial models were run on data from 1265 individuals aged 6-18 years, comprising 920 participants from ADHD sibling pairs and 345 control participants. Cognitive assessments included a four-choice reaction time (RT) task, a go/no-go task, a choice-delay task and an IQ assessment. The analyses focused on the cognitive variables of mean RT (MRT), RT variability (RTV), commission errors (CE), omission errors (OE) and choice impulsivity (CI).

RESULTS

Significant familial association (rF) was confirmed between cognitive performance and both ADHD (rF=0.41-0.71) and IQ (rF=-0.25 to -0.49). The association between ADHD and cognitive performance was largely independent (80-87%) of any contribution from etiological factors shared with IQ. The exception was for CI, where 49% of the overlap could be accounted for by the familial variance underlying IQ.

CONCLUSIONS

The aetiological factors underlying lower IQ in ADHD seem to be distinct from those between ADHD and RT/error measures. This suggests that lower IQ does not account for the key cognitive impairments observed in ADHD. The results have implications for molecular genetic studies designed to identify genes involved in ADHD.

Comparing total health care costs and treatment patterns of HIV patients in a managed care setting

The objective of this study was to investigate total health care costs and time to occurrence of hospitalization in HIV-infected patients treated according to the 1998 DHHS guidelines in a managed care setting. The study also investigated which patients do not receive guideline treatment. We used a retrospective cross-sectional study design using medical and pharmacy claims data. Data from 1,791 HIV-infected patients using antiretroviral agents between 1 February 1998 and 31 July 1999, including demographic characteristics, medication guideline use, medication adherence and cost of care, were examined. Factors associated with total health care costs and time-to-inpatient admission (as a proxy for patient outcomes) were assessed. Patients receiving guideline (HAART) therapy (55%) had higher prescription and total health care costs but lower medical costs. Patients not receiving treatment according to guidelines were more likely to be female, older, have comorbidities, lower medication adherence and no AIDS-defining illness. Treatment with HAART guidelines was associated with longer time-to-inpatient admission controlling for other factors. In a short-term cross-sectional analysis, patients treated with HAART guidelines had better outcomes based on time-to-inpatient admission but higher prescription and total health care costs. Some patients are at risk for not receiving care according to national treatment guidelines and may be targeted for intervention programmes.

Characterization of susceptibility and carrier status of burbot, Lota lota (L.), to IHNV, IPNV, Flavobacterium psychrophilum, Aeromonas salmonicida and Renibacterium salmoninarum

In this study, susceptibility and potential carrier status of burbot, Lota lota, were assessed for five important fish pathogens. Burbot demonstrated susceptibility and elevated mortality following challenge with infectious haematopoietic necrosis virus (IHNV) by immersion and to Aeromonas salmonicida by intraperitoneal (i.p.) injection. IHNV persisted in fish for at least 28 days, whereas A. salmonicida was not re-isolated beyond 17 days post-challenge. In contrast, burbot appeared refractory to Flavobacterium psychrophilum following intramuscular (i.m.) injection and to infectious pancreatic necrosis virus (IPNV) by immersion. However, i.p injection of IPNV resulted in re-isolation of virus from fish for the duration of the 28 day challenge. Renibacterium salmoninarum appeared to induce an asymptomatic carrier state in burbot following i.p. injection, but overt manifestation of disease was not apparent. Viable bacteria persisted in fish for at least 41 days, and bacterial DNA isolated by diagnostic polymerase chain reaction was detected from burbot kidney tissue 90 days after initial exposure. This study is the first to investigate susceptibility of burbot to selected fish pathogens, and this information will aid in efforts to culture and manage this species.

Nursing outside hospitals: the working experience of community nurses. Educational characteristics and job perceptions

The community nursing practice research project reports the results of a mailed questionnaire survey of nurses employed outside hospitals and nursing homes in Victoria in 1985. Two 10 per cent random samples stratified across practice areas were selected from listings of community nurses providing detailed employment information to the Victorian Nursing Council. An 84 per cent response rate was obtained from these listings yielding 689 responses. This paper reports that part of the study relevant to job entry, job satisfaction, job mobility and perceived career options as well as educational preparation. One half of community nurses entered community nursing after five years of hospital experience. The major reasons for choosing employment in community health nursing were its conditions of work, its autonomy and a dissatisfaction with hospital nursing, rather than a specific orientation to community nursing. These can be appreciated in terms of competing demands by the nurse's family life and her sense of growing professional maturity. Job satisfaction was high, with 87 per cent of nurses in the study population being satisfied or very satisfied. Only one quarter considered opportunities for career advancement to exist in their practice area. In the event only one fifth of nurses regarded promotion as important. The high levels of job satisfaction and the low importance attached to promotion are explicable given the nature of female employment and dissatisfaction with hospital nursing. Despite this high level of job satisfaction, one third of nurses believed they would not be nursing in five years time. Less than one third of nurses felt there was adequate opportunity for advancement in their practice area.(ABSTRACT TRUNCATED AT 250 WORDS)

Right-sided spatial difficulties in ADHD demonstrated in continuous movement control

Children with Attention Deficit Hyperactivity Disorder (ADHD) often show spatial attentional deficits, exhibiting a subtle rightwards bias, possibly due to dysfunction within the right hemisphere fronto-parietal network. Approximately 50% of children with ADHD also show signs of movement dysfunction. The nature of this movement dysfunction and possible interactions with spatial attention difficulties has not been clearly described. This study compared 31 children with and 31 children without ADHD on a movement kinematic task that tested hand-drawing movement precision. Participants used an electronic pen on a digitizing tablet. The pen tip position was sampled as X and Y coordinates at 200Hz. The task was to join targets of either 10 or 20mm diameter that were separated by a distance of 62.5 or 125 mm. Constant error in the X and Y planes, peak absolute velocity and acceleration, movement time, the number of pauses and pause time were analysed. Apart from a significantly increased rate of acceleration across all conditions, the children with ADHD demonstrated no temporal difficulties with the task; rather they showed subtle spatial difficulties, possibly suggestive of cerebellar involvement. The children with ADHD showed difficulties in accuracy of movement towards the right. They were less accurate in the X plane when moving towards the right-sided targets over the long distance. Greater variability in target accuracy was shown when moving towards the small target on the right side. The children with ADHD made significantly more pauses on the left target, when preparing the right movement, than the control group. These results suggest that the subtle spatial bias towards the right that has been demonstrated in ADHD in spatial attention also extends into the continuous movement domain.

Experiences of technology integration in home care nursing

The infusion of health care technologies into the home leads to substantial changes in the nature of work for home care nurses and their patients. Nurses and nursing practice must change to capitalize on these innovations. As part of a randomized field experiment evaluating web-based support for home care of patients with chronic heart disease, we engaged nine nurses in a dialogue about their experience integrating this modification of care delivery into their practice. They shared their perceptions of the work they needed to do and their perceptions and expectations for patients and themselves in using technologies to promote and manage self-care. We document three overarching themes that identify preexisting factors that influenced integration or represent the consequences of technology integration into home care: doing tasks differently, making accommodations in the home for devices and computers, and being mindful of existing expectations and skills of both nurses and patients.

Imaging amyloid deposition in Lewy body diseases

BACKGROUND

Extrapyramidal motor symptoms precede dementia in Parkinson disease (PDD) by many years, whereas dementia occurs early in dementia with Lewy bodies (DLB). Despite this clinical distinction, the neuropsychological and neuropathologic features of these conditions overlap. In addition to widespread distribution of Lewy bodies, both diseases have variable burdens of neuritic plaques and neurofibrillary tangles characteristic of Alzheimer disease (AD).

OBJECTIVES

To determine whether amyloid deposition, as assessed by PET imaging with the beta-amyloid-binding compound Pittsburgh Compound B (PiB), can distinguish DLB from PDD, and to assess whether regional patterns of amyloid deposition correlate with specific motor or cognitive features.

METHODS

Eight DLB, 7 PDD, 11 Parkinson disease (PD), 15 AD, and 37 normal control (NC) subjects underwent PiB-PET imaging and neuropsychological assessment. Amyloid burden was quantified using the PiB distribution volume ratio.

RESULTS

Cortical amyloid burden was higher in the DLB group than in the PDD group, comparable to the AD group. Amyloid deposition in the PDD group was low, comparable to the PD and NC groups. Relative to global cortical retention, occipital PiB retention was lower in the AD group than in the other groups. For the DLB, PDD, and PD groups, amyloid deposition in the parietal (lateral and precuneus)/posterior cingulate region was related to visuospatial impairment. Striatal PiB retention in the DLB and PDD groups was associated with less impaired motor function.

CONCLUSIONS

Global cortical amyloid burden is high in dementia with Lewy bodies (DLB) but low in Parkinson disease dementia. These data suggest that beta-amyloid may contribute selectively to the cognitive impairment of DLB and may contribute to the timing of dementia relative to the motor signs of parkinsonism.

Ulnocarpal arthrodesis for the treatment of radial agenesis in a dog

Forelimb deformity caused by radial agenesis was diagnosed in a one-year-old Shih Tzu dog. In contrast to most of the previously reported cases of radial agenesis, the humeroulnar joint was inherently stable. The deformity was treated by means of a one-stage ulnocarpal arthrodesis with the application of an eight hole dorsolateral arthrodesis bone plate and autogenous corticocancellous bone graft from the ilial wing. Radiographic evaluation at the eighth and sixteenth post-operative week showed evidence of union of the arthrodesis. At sixteen weeks post-operatively, the dog had much improved limb function. In humans afflicted with radial agenesis, ulnocarpal arthrodesis is used to restore forearm function by minimizing pain and decreasing the magnitude of angular deformity and instability at the level of the ulnocarpal joint. However, to our knowledge, this is the first report of treatment of radial agenesis in the dog by means of a one-stage, ulnocarpal arthrodesis.

Dopaminergic genotype biases spatial attention in healthy children

In everyday life, our sensory system is bombarded with visual input and we rely upon attention to select only those inputs that are relevant to behavioural goals. Typically, humans can shift their attention from one visual field to the other with little cost to perception. In cases of 'unilateral neglect', however, there is a persistent bias of spatial attention towards the same side as the damaged cerebral hemisphere. We used a visual orienting task to examine the influence of functional polymorphisms of the dopamine transporter gene (DAT1) on individual differences in spatial attention in normally developing children. DAT1 genotype significantly influenced spatial bias. Healthy children who were homozygous for alleles that influence the expression of dopamine transporters in the brain displayed inattention for left-sided stimuli, whereas heterozygotes did not. Our data provide the first evidence in healthy individuals of a genetically mediated bias in spatial attention that is related to dopamine signalling.

The application of microbore UPLC/oa-TOF-MS and 1H NMR spectroscopy to the metabonomic analysis of rat urine following the intravenous administration of pravastatin

The metabonomic effects of hepatotoxic doses of pravastatin on the urinary metabolic profiles of female rats have been investigated using ultra performance liquid chromatography (UPLC)-oa-TOF-MS and, independently, by (1)H NMR spectroscopy. UPLC was performed using a 1 mm microbore column packed with 1.7 microm particles. Examination of the data obtained from the individual animals, aided by statistical interpretation of the data, made it possible to identify potential markers for toxicological effects, with both NMR and UPLC-MS analysis highlighting distinct changes in the urinary metabolite profiles. These markers, which included elevated taurine and creatine, as well as bile acids, were consistent with hepatotoxicity in some animals, and this hypothesis was supported by histopathological and clinical chemistry findings. The analytical data from both techniques could be used to define a metabolic "trajectory" as toxicity developed and to provide an explanation for the lack of hepatotoxicity for one of the animals. The two analytical approaches (UPLC-MS and NMR) were found to be complementary whilst the use of a 1mm i.d. x 100 mm column reduced the amount of sample required for analysis to 2 microL, compared with 10 microL for a 2.1mm i.d. x 100 mm column. The 1mm i.d. column also provided increased signal-to-noise without loss of chromatographic efficiency.

Repeated dose toxicity and developmental toxicity of diisopropanolamine to rats

The repeated dose oral and dermal toxicity of diisopropanolamine (DIPA) was evaluated in rats and compared to the reported toxicity of the related secondary alcohol amine, diethanolamine (DEA). Fischer 344/DuCrl rats were given up to 750 mg/kg/day by dermal application, 5 days/week, for 4 weeks; or up to 1,000 mg DIPA/kg/day by drinking water for 13 weeks to evaluate potential toxic effects. Time-mated female CRL:CD(SD) rats were given up to 1,000 mg/kg/day by gavage on gestation days (GD) 6-20 for evaluation of maternal and fetal effects. In the dermal toxicity study, no adverse treatment-related in-life effects other than mild irritation at the site of dermal application at >or= 500 mg/kg/day were observed. There were no systemic effects in rats given up to 750 mg/kg/day. In the subchronic oral toxicity study, the most significant effects were an increase in absolute and relative kidney weights, unaccompanied by histopathologic changes, at >or= 500 mg/kg/day DIPA. The latter effect was ameliorated following a 4-week recovery period. In the developmental toxicity study, there were no maternal or developmental effects at any dose level evaluated. The toxicity of DIPA contrasts with that of DEA which has been shown to affect a number of organ systems when repeatedly administered orally or dermally at similar or lower dosages.

Psychosis of Alzheimer's disease: Gender differences in regional perfusion

We sought to determine whether the presence of psychotic symptoms in patients with Alzheimer's disease is associated with abnormal regional cerebral function. Perfusion single photon emission computed tomography images from 51 AD patients with psychotic symptoms were compared to images of 52 AD patients without such symptoms. Group comparisons were made with a voxel-based method, Statistical Parametric Mapping. We found that perfusion was lower in female patients with psychotic symptoms in right infero-lateral prefrontal cortex and in inferior temporal regions compared to female patients without such symptoms. In contrast, perfusion was higher in male patients with psychotic symptoms in the right striatum compared to male patients without such symptoms. Comparison groups did not differ in age or in dementia severity, as estimated by the Mini-Mental State Examination (MMSE). These results support the role of right hemisphere prefrontal and lateral temporal cortex in the psychosis of AD in women but not in men, and raise the possibility that these dysfunctional processes have a gender-specific regional pathophysiology in AD.

Single photon emission computed tomography perfusion differences in mild cognitive impairment

OBJECTIVE

To relate cerebral perfusion abnormalities to subsequent changes in clinical status among patients with mild cognitive impairment (MCI).

METHODS

Perfusion single photon emission computed tomography (SPECT) images were acquired in 105 elderly patients without dementia with MCI, using 99mTc-HMPAO. Clinical outcome after a 5-year follow-up period was heterogeneous.

RESULTS

Baseline SPECT data differed in those patients with MCI who were later diagnosed with Alzheimer's disease (the converter group) from those patients with MCI who experienced clinically evident decline but did not progress to a diagnosis of Alzheimer's disease within the follow-up period (the decliner group), from patients with MCI who had no clinical evidence of progression (the stable group), and from a group of 19 normal subjects (the control group). The most consistent decreases in relative perfusion in converters compared with the normal, stable and decliner groups were observed in the caudal anterior cingulate, and in the posterior cingulate. In addition, converters showed increased relative perfusion in the rostral anterior cingulate in comparison to the stable and decliner groups. A group of patients with Alzheimer's disease were also included for purposes of comparison. The group of patients with Alzheimer's disease at baseline differed from each of the other groups, with temporoparietal regions showing the most significant reductions in perfusion.

CONCLUSIONS

These results suggest that clinical heterogeneity in MCI is reflected in SPECT perfusion differences, and that the pattern of perfusion abnormalities evolves with increasing clinical severity.

Leukocyte transglutaminase 2 expression limits atherosclerotic lesion size

OBJECTIVE

Transglutaminase 2 (TG2), a broadly expressed regulator of protein cross-linking, wound healing, and tissue fibrosis, mediates apoptotic cell ingestion and transforming growth factor-beta release by macrophages and thereby can limit leukocyte-mediated inflammation. In atherosclerosis, oxidative stress and accumulation of unesterified cholesterol stimulate atherosclerotic lesion cell apoptosis. Cell death in advanced atherosclerotic lesions promotes lesion expansion and vulnerable plaques prone to rupture. Hence, we tested the hypothesis that leukocyte TG2 expression limits atherosclerosis.

METHODS AND RESULTS

We transplanted TG2-/- or TG2+/+ bone marrow into lethally irradiated low-density lipoprotein receptor (LDLR)-/- mice and evaluated diet-induced atherosclerosis after 16 weeks. We subsequently studied cultured TG2-/- and congenic TG2+/+ mouse macrophages for selected atherogenesis regulatory functions. Atherosclerotic aortic valve lesions in LDLR-/- recipients of TG2-/- bone marrow were larger and more subintimal lesional macrophage penetration than in TG2+/+ marrow recipients. Lesion intimal TG2 expression appeared robust in TG2+/+ but not TG2-/- marrow recipients. Cultured TG2-/- macrophages demonstrated diminished phagocytosis of apoptotic leukocytes, unaltered endocytosis, and degradation of oxidized LDL but decreased retinoic acid induction of the reverse cholesterol transport and apoptotic cell uptake mediator ABCA1.

CONCLUSIONS

We conclude that macrophage TG2 expression promotes both apoptotic cell clearance and ABCA1 expression in vitro and limits atherosclerotic lesion size in vivo.

Effects of pasteurization of potato slurry by-product fed in corn-or barley-based beef finishing diets1

Pasteurization of vegetable by-products such as potato slurry (PS) before feeding may be necessary to prevent the spread of pathogens and beef carcass blemishes. We hypothesized that pasteurization would increase ruminal fermentability of PS starch. Four ruminally cannulated crossbred beef steers (initial BW = 432) were used in a 4 x 4 Latin square experiment with a 2 x 2 factorial arrangement of treatments to examine the main effects and interactions of pasteurization (54.4 degrees C for 2 h) of PS and grain type (GT; dry-rolled corn and barley) on ruminal and total tract digestion of beef finishing diets. Diets contained 7% alfalfa hay and 14% PS (DM basis) and were fed ad libitum three times daily. Corn-based diets had 71.7% corn, whereas barley-based diets had 60% barley and 11.7% corn. Pasteurization resulted in greater (P = 0.004) soluble, rapidly degradable starch (34.3 vs. 26.7% for pasteurized and nonpasteurized PS, respectively). Ruminal fluid pH was more acidic (P < 0.07) for corn-based diets than for barley-based diets (P = 0.07) at 0200 and 2100 (sample time x GT; P < 0.05). Ruminal fluid pH was more acidic (P = 0.06) at 1400 for corn-based diets containing pasteurized PS compared with other dietary treatments (sample time x pasteurization x GT; P = 0.04). Minimum and maximum ruminal pH were greater (P < 0.10) for barley-based diets than for corn-based diets. Ruminal fluid pH was < 6.0 for a greater (P = 0.04) proportion of the day for corn-based compared with barley-based diets. In vitro incubation measurements revealed that pasteurization of PS resulted in lower (P = 0.06) ruminal fluid ammonia N concentration. Ruminal fluid ammonia N concentration was lower (P = 0.11) for barley-based diets than for corn-based diets. Steers fed barley-based diets had greater (P = 0.02) DMI and lesser (P < 0.05) total tract digestibility of DM and ADF compared with steers fed corn diets. Pasteurization increased (P = 0.10) total tract starch digestibility. Results indicate pasteurization increased rapidly degradable starch, ruminal starch fermentability, and total tract starch digestibility of PS. Grain type interacted with pasteurization such that feeding corn-based diets containing pasteurized PS resulted in periodic reductions in ruminal pH. Feeding management may be more critical when feeding pasteurized PS in beef finishing diets.

Chondrocyte calcium-sensing receptor expression is up-regulated in early guinea pig knee osteoarthritis and modulates PTHrP, MMP-13, and TIMP-3 expression

OBJECTIVE

Growth plate chondrocytes up-regulate calcium-sensing receptor (CaR) expression as they mature to hypertrophy. In cells other than chondrocytes, extracellular calcium-sensing via the CaR functions partly to promote expression of parathyroid hormone-related protein (PTHrP), a critical regulator of endochondral development. Moreover, PTHrP is up-regulated in human osteoarthritis (OA) and surgically induced rabbit OA cartilages and may promote both chondrocyte proliferation and osteophyte formation therein. Hence, we examined chondrocyte CaR-mediated calcium-sensing in OA pathogenesis.

METHODS

We studied spontaneous knee OA in male Hartley guinea pigs. We also evaluated cultured bovine knee chondrocytes and immortalized human articular chondrocytes (CH-8 cells), employing the CaR calcimimetic agonist NPS R-467 or altering physiologic extracellular calcium (1.8 mM).

RESULTS

Immunohistochemistry revealed that CaR expression became up-regulated in the superficial zone at 4 months of age in the guinea pig medial tibial plateau cartilage as early OA developed. CaR expression later became up-regulated in the middle zone. PTHrP content, measured by immunoassay, was significantly increased in the medial tibial plateau cartilage as OA developed and progressed. In cultured chondrocytic cells, CaR-mediated extracellular calcium-sensing, stimulated by the calcimimetic NPS R-467, induced PTHrP and matrix metalloproteinase (MMP)-13 expression and suppressed expression of tissue inhibitor of metalloproteinase (TIMP)-3 dose-dependently, effects shared by elevated extracellular calcium (3 mM). Extracellular calcium-sensing appeared essential for PTHrP and interleukin (IL)-1 to induce MMP-13 and for PTHrP 1-34 to suppress TIMP-3 expression.

CONCLUSIONS

Chondrocyte CaR expression becomes up-regulated early in the course of spontaneous guinea pig knee OA. Chondrocyte CaR-mediated extracellular calcium-sensing promotes PTHrP expression, modulates the effects of PTHrP and IL-1, and promotes MMP-13 expression and TIMP-3 depletion. Our results implicate up-regulated extracellular calcium-sensing via the CaR as a novel mediator of OA progression.

Diethylene glycol monobutyl ether (DGBE): two- and thirteen-week oral toxicity studies in Fischer 344 rats

Standard toxicologic endpoints, supplemented by additional examinations, were studied for groups of 10 Fischer 344 rats/sex given drinking water formulated to supply 0, 50, 250, or 1000 mg diethylene glycol monobutyl ether (DGBE)/kg/day for 13 weeks. These dose levels were based upon initial investigations using drinking water formulated to supply 0, 1000, 1500 or 2000 mg DGBE/kg/day for two weeks. All rats survived the respective treatment intervals with no adverse treatment-related in-life effects, including no alterations in a functional observational battery. In both studies, rats given > or = 1000 mg/kg/day consumed less water and feed and weighed slightly less than controls. For rats given > or = 1000 mg DGBE/kg/day, the liver and red blood cells (RBC) were the primary target organs although the effects were slight. In the 13-week study, rats given 1000 mg/kg/day had statistically significant increased relative liver weight (7-10%) and hepatic cytochrome P450s (24-39%) and UGT (approximately 16%) levels along with slight, statistically significant, decreases in serum total protein, cholesterol and aspartate aminotransferase. Histopathologically, very slight hepatocyte hypertrophy and increased individual hepatocyte degeneration were found in females only. At 1000 mg/kg/day, the RBC count, hemoglobin (Hgb) and hematocrit (Hct) were minimally, but statistically significantly, decreased (5.1-8.7%) but RBC morphology, RBC indices, reticuloctye count and bone marrow and spleen histopathology were unaffected. Absolute and relative kidney weights statistically significantly increased (6-13%) with an equivocal increase in minor histopathologic changes typical of early spontaneous nephropathy. There were no adverse effects on urinalysis, clinical chemistry, sperm parameters or testis histopathology. At 250 mg/kg/day, there were equivocal decreases (approximately 2-3%) in RBC count, Hgb and Hct that were statistically significant for the RBC count and Hgb, but these changes were within the historical control range. This dose level was considered the no adverse effect level (NOAEL).