Biomedical subjects

R A Erdman

Publications and source records attributed to R A Erdman.

At least 19 recordsLinked to original sources

PubMed2004

A new instrument for assessing quality of life in atopic dermatitis: international development of the Quality of Life Index for Atopic Dermatitis (QoLIAD).

BACKGROUND: Atopic dermatitis (AD) is a chronic or chronically relapsing inflammatory skin condition that can have a considerable impact on those affected. There are a number of instruments available to measure outcome in dermatological conditions but none have been developed specifically for AD. In addition, most measure symptoms and/or daily functioning, which are potential influences on quality of life (QoL) rather than assessments of the construct itself. OBJECTIVES: The aim of the current study was to develop a new instrument specifically designed to measure QoL in adults with AD-the Quality of Life Index for Atopic Dermatitis (QoLIAD). METHODS: The instrument was developed based on the needs-based model of QoL and was produced in several different countries simultaneously. Its content was derived from 65 in-depth interviews with relevant patients in the U.K., Italy and the Netherlands. The initial version of the measure was produced in U.K. English and translations were produced for the Netherlands, Italy, Germany, France and the U.S.A. using a dual translation panel methodology. A Spanish version was developed using the same adaptation process after the instrument was finalized. Field-test interviews were conducted with approximately 20 patients in each country to assess face and content validity. The instrument [in addition to the Dermatology Life Quality Index (DLQI) and the Psychological General Well-Being Schedule (PGWB)] was then administered to up to 300 AD patients in each country at two time points to finalize the instrument and test its psychometric properties. RESULTS: The initial version of the QoLIAD had 56 items that reflected the areas of need fulfillment identified in the qualitative interviews as having been affected by AD: mental and emotional stimulation, physical and emotional stability, security, sharing and belonging, self-esteem, personal development and fulfillment. Comments from patients in field-test interviews resulted in the removal of 14 items, to leave a 42-item instrument that was considered relevant and acceptable. The number of patients participating in the survey were 286 in the U.K., 46 in the Netherlands, 213 in France, 187 in Germany, 178 in the U.S.A. and 83 in Spain. Application of the Rasch model to these data identified the final 25-item QoLIAD. Unidimensionality was confirmed, with deviation of the total scale from the Rasch model evident at a single time point in one country only (the U.K.). All language versions, with the exception of the Dutch measure, had test-retest reliability coefficients in excess of 0.85. The test-retest in the Netherlands was 0.80. However, this country had the smallest sample size and the corresponding reliability for the DLQI was only 0.40. The QoLIAD had adequate internal consistency and the initial indications of construct validity were good. The levels of association with the DLQI indicated that the two instruments measure related but distinct constructs. CONCLUSIONS: The QoLIAD is a practical, reliable, valid and culturally applicable instrument for measuring the impact of AD and its treatment on QoL in clinical trials or in routine clinical practice.

Adolescent↗

PubMed2004

Changes in milk fat in response to dietary supplementation with calcium salts of trans-18:1 or conjugated linoleic fatty acids in lactating dairy cows.

Milk fat was investigated in lactating dairy cows fed diets supplemented with Ca salts of trans fatty acids (Ca-tFA) or Ca salts of conjugated linoleic acids (Ca-CLA). Forty-five Holstein cows (115 days in milk) were fed a control diet (51% forage; dry matter basis) supplemented with 400 g of EnerG II (Ca salts of palm oil fatty acids) for 2 wk; subsequently, 5 groups of 9 cows each were assigned for 4 wk to the control diet or diets containing 100 g of Ca-CLA or 100, 200, or 400 g of Ca-tFA in a randomized block design. Treatments had no effect on dry matter intake, milk production, protein, lactose, or somatic cell count. Milk fat percentage was reduced from 3.39% in controls to 3.30, 3.04, and 2.98%, respectively, by the Ca-tFA diets and to 2.54% by the Ca-CLA diet. Milk fat yield (1.24 kg/d in controls) was decreased by 60, 130, and 190 g/d with increasing dose of Ca-tFA and by 290 g/d with the Ca-CLA supplement. Consistent with increased endogenous synthesis of cis-9-containing CLA from precursors provided by the Ca-tFA diets, total CLA were similar in milk of cows fed Ca-CLA or Ca-tFA. Compared with controls, the Ca-CLA diet increased trans-10, cis-12-18:2 yield in milk, without altering levels of trans-18:1 isomers. In contrast, yields of most trans-18:1 isomers were elevated in milk of cows fed Ca-tFA diets, whereas yields of trans-10, cis-12-18:2 remained similar to control values. We conclude that milk fat depression can occur without an increase in trans-10, cis-12-18:2 in milk and that other components, perhaps the trans-10-18:1 isomer, may be involved.

Animal Feed↗

PubMed2004

Bovine somatotropin and rumen-undegradable protein effects in prepubertal dairy heifers: effects on body composition and organ and tissue weights.

The objectives of this study were to determine the effect of recombinant bovine somatotropin (bST) and added dietary rumen undegradable protein (RUP) on organ and tissue weights and body composition in growing dairy heifers. Thirty-two Holstein heifers were in the experiment, 8 killed initially at 3 mo of age, with the remaining 24 Holstein heifers randomly assigned to treatments (n = 6) consisting of 0.1 mg/kg of body weight per day of bST and 2% added dietary RUP (dry matter basis) applied in a 2 x2 factorial design. A total of 6 heifers per treatment group (3 each at 5 and 10 mo of age), were slaughtered to determine body composition and organ masses. Feed intake measured from group intakes were increased by 0.25 and 0.35 kg/d with bST and RUP, respectively. Administration of bST tended to increase the weights of visceral organs including heart, kidney, and spleen by 16, 16, and 38%, respectively. At 10 mo of age, there was a trend for increased empty body weights (EBW) and non-carcass components for heifers treated with bST, but there were no effects of RUP. Body components and organ weights, expressed as a percentage of BW were not affected by RUP or bST. Somatotropin increased ash weight at 10 mo without affecting amounts of protein, fat, and energy. Rates of ash deposition between 3 and 10 mo of age were increased 7 and 4 g/d by bST and RUP, respectively. There were no treatment effects on rates of body fat, protein, and energy deposition. Bovine somatotropin and RUP altered the metabolism of growing heifers in a manner that was consistent with increased rates of skeletal growth. This suggests that nutritional and endocrine manipulations could increase growth rates of skeletal tissues without increasing fat deposition in prepubertal dairy heifers.

Aging↗

PubMed2004

Bovine somatotropin and rumen-undegradable protein effects on skeletal growth in prepubertal dairy heifers.

The objectives of this study were to determine the effects of dietary rumen-undegradable protein (RUP) and bovine somatotropin (bST) during the period from weaning until puberty on body weight (BW) and skeletal growth rates and age at puberty. Fifty-one Holstein heifers at 90 d of age were randomly assigned to 4 treatment groups consisting of 0.1 mg/kg BW per day of bST and 2% added dietary RUP (dry matter basis) applied in a 2 x 2 factorial design (n = 13 per group, except bST with no RUP group, n = 12). From 90 to 314 d, bST increased average daily gain (ADG) by 0.07 kg/d and BW by 16.2 kg, while added RUP increased ADG by 0.10 kg/d and BW by 21.4 kg. Both bST and added RUP effects on BW and ADG were additive. Skeletal growth rates, as measured by withers height (WH) and hip height (HH) were increased by both bST and added RUP. Somatotropin and RUP increased WH by 1.8 and 2.7 cm and hip height by 2.5 and 4.0 cm, respectively, at 314 d of age. Growth curves showed that added RUP effects on rates of BW, WH, and HH growth were greatest from 90 to 150 d age and diminished thereafter, suggesting that protein was limiting during this time period. Conversely, bST effects tended to be greater as the heifers approached puberty, but only in the presence of added RUP. Age at puberty was not affected by treatment, averaging 314 d of age across treatments. From 314 to 644 d of age, rates of BW, WH, and HH growth were similar among treatment groups. However, treatment differences present at 314 d of age persisted through 644 d of age, more than 10 mo after treatments ceased. These results suggest that protein during the early postweaning period and bST during the 200 to 300 d of age period just prior to puberty could be used to accelerate simultaneous increases in both BW and skeletal growth rates in dairy heifers without reducing age at puberty.

Aging↗

PubMed2003

Lactation persistency: insights from mammary cell proliferation studies.

A persistent lactation is dependent on maintaining the number and activity of milk secreting cells with advancing lactation. When dairy cows are milked twice daily, the increase in milk yield from parturition to peak lactation is due to increased secretory activity per cell rather than to accretion of additional epithelial cells. After peak lactation, declining milk yield is due to loss of mammary epithelial cells by apoptosis. During lactation, only 0.3% of mammary cells proliferate in a 24-h period. Yet this proliferative rate is sufficient to replace most mammary epithelial cells by the end of lactation. Management practices can influence lactation persistency. Administration of bovine somatotropin may enhance persistency by increasing cell proliferation and turnover, or by reducing the rate of apoptosis. Increased photoperiod may also increase persistency of lactation by mechanisms that are as yet undefined. Increased milking frequency during the first weeks of lactation increases milk yield, even after return to less frequent milking, with increases of approximately 8% over the entire lactation. A mammary cell proliferation response to frequent milking during early lactation appears to be involved. Conversely, advanced pregnancy, infrequent milking, and mastitis increase death of epithelial cells by apoptosis. Regulation of mammary cell renewal provides a key to increasing persistency. Investigations to characterize epithelial cells that serve as the proliferative population in the bovine mammary gland have been initiated. Epithelial cells that stain lightly in histological sections are evident through all phases of mammary development and secretion and account for nearly all proliferation in the prepubertal gland. Characterization of these cells may provide a means to regulate mammary cell proliferation and thus to enhance persistency, reduce the effects of mastitis, and decrease the necessity for a dry period.

Animals↗

PubMed2003

Effect of feeding supplemental fibrolytic enzymes or soluble sugars with malic acid on milk production.

Two trials were conducted to evaluate effects of feeding supplemental fibrolytic enzymes or soluble sugars and malic acid on milk production. In trial 1, 257 cows at four sites were fed a basal diet consisting of no more than 60% of forage DM as corn silage and less than 40% as alfalfa hay. Cows were assigned randomly within site, parity, and two stages of lactation to: 1) control; 2) enzyme A; 3) enzyme B; and 4) soluble sugars and malic acid. There was a 14-d pretreatment and an 84-d treatment period. Enzyme solutions were sprayed on either the forage component or the TMR each day while mixing feed. Trial 2 was similar, except 122 cows at one site in the United Kingdom were fed diets containing forage that was 75% corn silage and 25% grass silage, and all cows began the study between 25 to 31 DIM. Mean milk productions for 233 cows that completed trial 1 were 32.9, 32.5, 32.4, and 32.9 kg/d for control, enzyme A, enzyme B, and soluble sugars and malic acid, respectively. Mean milk productions for 116 cows that completed trial 2 were 28.2, 27.9, 28.8, and 28.4 kg/d, respectively. In vitro analyses of the activities of enzyme solutions indicated that all major cellulose and hemicellulose degrading activities were present; however, the pH optima (approximate pH = 4 to 5) were more acidic, and the temperature optimum (approximately 50 degrees C) was greater than normal pH and temperature in the rumen. If fibrolytic activity in the rumen is a major mechanism of action of supplemental fibrolytic enzymes, it appears that considerable activity of these preparations was lost due to conditions in the rumen. In conclusion, feeding supplemental fibrolytic enzymes or malic acid with soluble sugars had no effect on milk production under the conditions used in this study.

Animal Nutritional Physiological Phenomena↗

PubMed2003

Milk yield and mammary growth effects due to increased milking frequency during early lactation.

Increased milking frequency (IMF) at the beginning of lactation has been shown to increase milk yield not only during IMF but also after its cessation. The objectives of this experiment evaluated the effects of increased milking frequency initiated during early lactation on mammary growth and effects on milk yield (MY). Thirty-one cows were divided into treatment groups: 1) 2X: cows milked twice daily (2X) beginning at parturition (d 1), 2) IMF1: cows milked four times daily (4X) from d 1 to 21 postpartum (PP) and 3) IMF4: cows milked 2X d 1 to 3 and 4X d 4 to 21 PP. The 4X cows were milked immediately before 2X cows and again approximately 3 h later, at the end of the normal milking routine. All cows were milked 2X from d 21 to 305 postpartum. Milk yields were 34.5, 37.8 and 37.6 kg/d during wk 1 to 44 for 2X, IMF1 and IMF4, respectively. Mammary biopsies from four cows per treatment were obtained on d 7 and 14 PP to evaluate mammary cell proliferation. Tritiated-thymidine incorporation tended to increase on d 7 in IMF1 cows, and arithmetic means of the percentage of cells expressing Ki-67 proliferation antigen were consistent with a proliferative response to IMF though not significant. Blood was sampled three times per wk during the first 2 wk and then once per wk during wk 3, 4, 5, 6, 8, and 10. Plasma insulin-like growth factor-1 (IGF-1) averaged 20.1 ng/ml in IMF cows vs. 24.2 in 2X but was not accompanied by a change in bST. Prolactin was also not affected by treatment. Neither milk yield nor potential effects on mammary cell proliferation were correlated with systemic IGF-1. Implementing an IMF routine increases MY during treatment and elicits a carryover effect on the remainder of lactation. Milk yield responses after an IMF routine may be the result of increased mammary cell proliferation.

Animals↗

PubMed2002

Relation of growth hormone response to growth hormone-releasing hormone to estimation of milk production via deuterium oxide dilution in beef cattle.

Current methods of estimating milk production in beef cows can be time-consuming, labor-intensive, and subject to high variability. The weigh-suckle-weigh (WSW) method requires repeated separation of offspring from their dams. Machine milking requires that animals be acclimated to the equipment prior to the estimation. The objective of Exp. 1 was to validate a deuterium oxide (D2O) dilution method of estimating milk production in cattle. In Exp. 1, Holstein calves (n = 5) averaging 29+/-2 d of age and 52.6+/-2.5 kg (+/- SE) were used as the model. Blood was collected for baseline D2O measurements followed by an injection of 300 mg D2O/kg BW. Syringes were weighed before and after the injection to gravimetrically determine the dose. Another blood sample was collected after D2O was allowed to equilibrate with body water for 2 h, and on each of the next five consecutive days, prior to feeding. Actual milk intake was measured by disappearance (i.e., amount of milk replacer offered to the calf minus the amount refused). Deuterium oxide in plasma was measured by mass spectrometry and milk intake was computed from the disappearance curve of D2O in blood plasma for each calf. Accumulated milk intake estimated by D2O dilution was highly correlated (y = 0.9x + 0.6; R2 = 0.99; P < 0.001) with actual milk intake. The objectives of Exp. 2 were to determine whether 1) D2O dilution was comparable to a standard measure of milk production in beef heifers and 2) growth hormone (GH) response to GH-releasing hormone (GHRH) in heifers at weaning is predictive of subsequent milk production. Deuterium oxide dilution and WSW were compared using 14 first-calf Angus heifers and their calves. Deuterium oxide dilution was used to estimate milk production of 40 first-calf Angus heifers that had been challenged with GHRH at weaning. Results indicate that the D2O dilution method is correlated (R2 = 0.89; P = 0.04) to the WSW estimation of milk production. Growth hormone response to GHRH in weanling heifers is positively related (R2 = 0.22; P = 0.03) to their subsequent milk production. Deuterium oxide dilution in calves offers an additional approach to the estimation of milk production of the dam in typical beef cattle production settings.

Animals↗

PubMed2001

Different Rab GTPases associate preferentially with alpha or beta GDP-dissociation inhibitors.

GDIs (GDP-dissociation inhibitors) bind to Rab GTPases and mediate their membrane targeting and recycling. In vitro, most Rabs can bind to either of the major isoforms of GDI, leading to the assumption that the proportion of each specific Rab/GDI complex in vivo reflects the relative abundance of the alpha versus beta forms of GDI. Here we show that when human teratocarcinoma cells (Ntera2) are induced to differentiate into postmitotic neurons (NT2N), there is a major change in the proportion of GDIalpha relative to GDIbeta. Under these conditions, certain Rab GTPases associate preferentially with either GDIalpha or GDIbeta, irrespective of the relative abundance of the GDI isoform. These findings suggest that heretofore unrecognized functional specificity may exist between the two major forms of GDI.

Animals↗

PubMed2001

Feelings of being disabled as a predictor of mortality in men 10 years after percutaneous coronary transluminal angioplasty.

OBJECTIVE: To examine the independent prognostic value of the four subscales of the Heart Patients Psychological Questionnaire (HPPQ) on mortality in male and female patients 10 years following percutaneous transluminal coronary angioplasty (PTCA). METHODS: The HPPQ, which measures well-being, feelings of being disabled, despondency, and social inhibition, was administered to 356 patients (23% women) post-PTCA. The patients were followed for a median of 10 years. Clinical and demographic variables were sampled from medical records. RESULTS: During the follow-up period, 104 patients (29%) had died. Women scored significantly worse on all psychological subscales compared with men. Fifty-nine (72%) women and 92 (34%) men had a score indicating at least mild to moderate feelings of being disabled. Men scoring high on feelings of being disabled were at increased risk of mortality compared with men having a low score, adjusted for other cardiac risk factors (chi(2)=7; P=.008). No differences were found between women with low or high scores on feelings of being disabled (relative risk (RR): 1.2; 95% confidence interval (CI): 0.5-3.3). None of the other HPPQ subscales were related to mortality. CONCLUSION: Feelings of being disabled measured at least 1 year after hospital discharge is a significant predictor of mortality in men 10 years post-PTCA, but not in women. This finding adds to the increasing knowledge that psychosocial variables influence morbidity and mortality in cardiac patients.

Adult↗

PubMed2001

Evaluation of the Dutch version of the migraine quality of life instrument (MSQOL) and its application in headache coping.

The Dutch version of the MSQOL was evaluated psychometrically and applied in a convenience sample of 90 migraine patients from the Dutch Society of Headache Patients. Internal consistency and test-retest reliability of the Dutch MSQOL were good (> 0.90) and comparable with those of the original English version. The measure also had good validity, with its scores associated as expected with headache intensity, psychological well-being and level of patient functioning. Respondents who employ more passive methods of coping with their headaches, such as 'worrying', 'retreating' and 'resting', had worse quality of life. 'Worrying' was particularly associated with diminished quality of life, suggesting that cognitive interventions might be of benefit to migraineurs who use this method of coping.

Adaptation, Psychological↗

PubMed2001

Effects of brown midrib corn silage on the energy balance of dairy cattle.

Effects of genotype and level of intake on net energy for lactation values of corn silage were evaluated by indirect calorimetry in two experiments using lactating and dry, nonpregnant dairy cows. In experiment 1, six multiparous Holstein cows in early lactation were fed experimental diets containing either brown midrib (bm3) or isogenic normal corn silage. Dietary treatments were isogenic and bm3 diets fed ad libitum, and the bm3 diets restricted-fed. Dry matter (DM) intake was 2.4 kg/d greater for cows fed the bm3 diet ad libitum compared with cows fed the isogenic diet. Apparent digestibilities of DM, organic matter, neutral detergent fiber, and acid detergent fiber were greater for cows restricted-fed bm3 than the isogenic diet. In experiment 2, six dry, nonpregnant Holstein cows were fed maintenance diets containing either bm3 or isogenic corn silage. Apparent digestibilities of DM, organic matter, neutral detergent fiber, and acid detergent fiber were greater for cows fed bm3 compared with isogenic corn silage. Digestible energy and metabolizable energy were greater for maintenance diets containing bm3 compared with isogenic corn silage, respectively. These data indicate increased milk production seen in other studies is a result of increased DMI rather than an increase in energy efficiency. Increased organic matter digestibility of bm3 corn silage resulted in greater digestible energy and metabolizable energy values in cows fed at maintenance energy intake. However, calculated net energy for lactation values of bm3 and isogenic corn silages were similar at both productive and maintenance levels of feeding.

Animals↗

PubMed2001

Effect of somatotropin on thyroid hormones and cytokines in lactating dairy cows during ad libitum and restricted feed intake.

Twelve Holsteins in first lactation were used to investigate the relationship between energy balance and effects of bovine somatotropin (bST) on thyroid hormone metabolism and cytokine concentrations in serum. Six cows were fed for ad libitum intake and six cows were feed restricted to induce negative energy balance during two treatment periods of 6 d. During treatment periods, cows were administered vehicle or 40 mg of bST/d according to a crossover design. Between treatment periods was a 15-d recovery period, during which all cows were fed ad libitum. Cows that were fed ad libitum remained in positive energy balance during control and bST treatments, whereas cows that were fed for restricted intake were in negative energy balance during control and bST treatment periods. In both dietary groups, bST decreased energy balance. Milk production and the fat percentage of milk increased during bST treatment in both dietary groups. Fat-corrected milk yield was increased 13% by bST treatment. Serum concentrations of IGF-I did not differ between dietary groups but were greater during bST than control periods. Serum thyroxine concentration was decreased by bST treatment. Serum triiodothyronine and reverse-triiodothyronine were not altered by hormone treatment, but circulating concentrations of thyroid hormones were apparently reduced by dietary restriction. Neither hepatic nor mammary thyroxine 5'-deiodinase was affected by bST treatment. Plasma concentration of tumor necrosis factor-alpha, a potential regulator of thyroxine 5'-deiodinase, was not affected by bST treatment. Short-term treatment with bST did not influence thyroid hormone metabolism in lactating cows in positive or negative energy balance.

Animals↗

PubMed2001

Ruminal fermentation and intestinal flow of nutrients by lactating cows consuming brown midrib corn silages.

Rumen characteristics and digestive kinetics of brown midrib corn silage were evaluated with five late-lactation (221 DIM +/- 20 d) multiparous cows fitted with ruminal and duodenal cannula. Dietary treatments were applied by using a single reversal design with two 21-d periods where either brown midrib (BM3) or isogenic (ISO) corn silage were included in a total mixed ration formulated to be 40% concentrate and 60% corn silage on a dry matter (DM) basis. Rumen and total tract digestibilities of DM, organic matter, neutral detergent fiber, acid detergent fiber, starch, and N were determined and rumen characteristics evaluated. Apparent rumen DM and organic matter digestibilities were greater for the BM3 corn silage (7.1 and 4.7 percentage units, respectively). Dietary intake and duodenal flow of starch were greater and rumen and total tract starch digestibilities were lower for BM3 corn silage diets than ISO corn silage diets. However, more starch (1.1 kg/d) was apparently digested and absorbed postruminally in cows fed the BM3 corn silage diets. Duodenal flow of neutral detergent fiber was 0.9 kg/d lower, and ruminal (15.9 percentage units) and total tract digestibilities (4.4 percentage units) were higher for BM3 treatment compared with the ISO treatment. Digestive patterns of ADF were similar for the BM3 and ISO treatments. Ruminal pH was lower in the cows fed the BM3 corn silage than those fed the ISO corn silage. As a result of a tendency for decreased N excretion in urine and slight increases in N intake due to increased DM intake, N balance tended to be greater for the BM3 treatment compared with the ISO treatment. These results may partially explain the benefits of feeding BM3 corn silage to cows during early lactation, as the observed increases in fiber component digestibility and improved N economy may combine to enhance DM intake and better support the nutritional demands of milk production for the high producing dairy cow.

Animal Nutritional Physiological Phenomena↗

PubMed2000

Rab24 is an atypical member of the Rab GTPase family. Deficient GTPase activity, GDP dissociation inhibitor interaction, and prenylation of Rab24 expressed in cultured cells.

The function of Rab24 is currently unknown, but other members of the Rab GTPase family are known to participate in various protein trafficking pathways. Rab proteins are thought to cycle on and off vesicle membranes in conjunction with changes in their guanine nucleotide state. The present studies indicate that Rab24 possesses several unusual characteristics that distinguish it from other Rab proteins. 1) Based on [(32)P]orthophosphate labeling of protein-bound nucleotide, Rab24 exists predominantly in the GTP state when expressed in cultured cells. The low GTPase activity is related to the presence of serine instead of glutamine at the position cognate to Ras Gln-61. 2) Posttranslational geranylgeranylation of Rab24, determined by metabolic labeling or detergent partitioning assays, is inefficient when compared with other Rabs ending with the common CXC and CC carboxyl-terminal motifs. This is partly due to the presence of two histidines distal to the target cysteines, but also involves other unidentified features. 3) Most of the Rab24 in the cytoplasmic compartment of cultured cells is not associated with Rab GDP dissociation inhibitors. These findings indicate that, if Rab24 functions in vesicular transport processes, it may operate through a novel mechanism that does not depend on GTP hydrolysis or GDP dissociation inhibitor-mediated recycling.

Amino Acid Sequence↗

PubMed2000

[Regional differences in prehospital time delay for patients with acute myocardial infarction; Rotterdam and Groningen, 1990-1995].

OBJECTIVE: To describe pre-hospital delay times in patients with acute myocardial infarction (AMI) in two regions in the Netherlands: Groningen (a region with high mortality for coronary heart disease (CHD)) and Rotterdam (a region with low CHD mortality). DESIGN: Descriptive. METHOD: The pre-hospital treatment delay of AMI patients in Rotterdam in 1990-1991 versus 1993-1995 was compared and also compared between Groningen en Rotterdam (1993-1995). In each region 3 hospitals participated (1 academic, 2 regional). The data were collected with a structured interview within 7 days after onset of symptoms in hospitalized AMI patients (n = 924) or by interviewing relatives of deceased patients (n = 40). The median patient, general practitioner (GP) and ambulance delays were calculated. RESULTS: Total median pre-hospital delay was 2.5 hours (5-95-percentile: 50 min-36 hours). Median patient delay time was shorter in Groningen than in Rotterdam (respectively 30 and 45 min) and the same applied to doctor delay times (respectively 38 and 72 min). In Rotterdam doctor delay time decreased by 23 min between 1990-1991 and 1993-1995. Median ambulance delay was 30 min in Rotterdam and 35 min in Groningen. Total pre-hospital delay times of self referred patients were 32-78 min shorter than those of patients who consulted a GP before admission. CONCLUSION: Reduction of pre-hospital delay in Rotterdam between 1990-1991 and 1993-1995 was due to faster decision time by the GP. The short pre-hospital treatment delay in Groningen in hospitalized patients suggests that relatively more AMI patients die outside hospital which may contribute to the high CHD mortality in this region.

Emergency Medical Services↗

PubMed2000

Mammary lipogenic enzyme activity, trans fatty acids and conjugated linoleic acids are altered in lactating dairy cows fed a milk fat-depressing diet.

The objectives of the present study were to examine the effect of a milk fat-depressing (MFD) diet on: 1) the activity of mammary acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS), 2) ACC mRNA relative abundance and 3) distributions of conjugated linoleic acids (CLA) and trans-18:1 fatty acids (tFA) in milk fat. Twelve lactating Holstein cows were used in a single reversal design. Two diets were fed: a control diet (60:40% forage/concentrate) and an MFD diet (25:70% forage/concentrate, supplemented with 5% soybean oil). The MFD diet decreased (P: < 0 0.001) milk fat by 43% and ACC and FAS activity by 61 and 44%, respectively. A reduced ACC mRNA relative abundance (P: < 0.001) corresponded with the lower ACC activity. The fatty acids synthesized de novo were decreased (P: < 0. 002), whereas tFA were increased from 1.9 to 15.6% due predominantly to a change in trans-10-18:1 isomer (P: < 0.001). With the MFD diet, the trans-7, cis-9 and trans-10, cis-12 CLA isomers were elevated (P: < 0.001), in contrast to the decrease in trans-11-18:1 (P: < 0. 001) and cis-9, trans-11-18:2. The data were consistent with a dietary effect on mammary de novo FA synthesis mediated through a reduction in ACC and FAS activity and in ACC mRNA abundance. The results were compatible with a role of trans-10, cis-12 CLA in milk fat depression, but alterations noted in tFA and other CLA isomers suggest that they also may be important during diet-induced milk fat depression.

Acetyl-CoA Carboxylase↗

PubMed2000

Effects of photoperiodic manipulation during the dry period of dairy cows.

Thirty-four lactating Holstein cows were dried off 60 d prior to their expected calving date, paired by calving date, and randomly assigned to one of two photoperiod treatments: long-day photoperiod (n = 18; 16 h light: 8 h dark/d) or a short-day photoperiod (n = 16; 8 h light: 16 h dark/d) to determine if manipulation of photoperiod during the dry period would impact milk yield in the subsequent lactation. At parturition, calf weight, height, and length were measured and the cows were moved into ambient lighting conditions (November 1996 to January 1997 and November 1997 to January 1998, 39 degrees latitude) with the rest of the University of Maryland herd. After parturition, milk yield and composition were measured for 16 wk. Prolactin concentrations were higher by 11.7 ng/ml in the long-day photoperiod treatment group than for the cows on a short-day photoperiod. During lactation cows previously exposed to a short-day photoperiod produced 3.2 kg/d more milk than long-day photoperiod cows. Energy-corrected milk yield was greater in short-day photoperiod than in long-day photoperiod cows. Treatment did not affect calf growth, milk composition, or plasma insulin growth factor I concentrations. In conclusion, manipulation of photoperiod during the dry period of dairy cows may be a useful management tool for increasing milk yield in the subsequent lactation.

Animals↗