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PubMed1986

Validation and application of single breath cardiac output determinations in man.

Cardiac outputs by single breath (Qsb) and Fick (Qf) procedures were compared in five healthy males during supine rest and exercise with Qf ranging from 6-19 L X min-1. The prolonged exhalation (SB) was not controlled. The Qsb calculations incorporated an equation of the CO2 dissociation curve and a "moving spline" sequential curve-fitting technique to calculate the instantaneous R from points on the original expirogram. The resulting linear regression equation for all 38 comparisons obtained (r = +0.76, p less than 0.001, mean difference +/- S.D. = 2.93 +/- 2.72 L X min-1) indicated a 24% underestimation of Qf. A substantial portion of the variability during exercise (n = 28) was due to a difference in alveolar ventilation between the time of the mixed expired (E) gas collection and the SB maneuver. When Qsb was corrected (Qsb) by a linear regression based on the difference between Re and Rsb during exercise and by adding 2.44 L X min-1 at rest (the mean difference), the relationship was greatly improved (Qsb = 0.14 + 0.99 Qf, r = +0.93, mean difference +/- S.D. = 0 +/- 1.47 L X min-1). A subsequent study during upright rest and exercise to 80% of VO2max in 6 subjects indicated a close linear relationship between Q'sb and VO2 for all 95 values obtained (r = +0.94), with slope and intercept close to published studies utilizing invasive cardiac output measurements. Considerations of measured blood gases in relation to estimated values suggested that underestimates of Qf arose, at least in part, from arterial desaturation during the SB maneuver. Detailed computational procedures are provided for implementing this improved Qsb procedure.

Adult↗

PubMed2003

[Body mass index and triceps skinfold correlation in children from Paulínia city, São Paulo, SP].

UNLABELLED: Body mass index (BMI) has been considered a criterion to define and analyse obesity in adults and children. BACKGROUND: the purpose of this study was to evaluate the correlation between BMI and triceps skinfold (TSF). METHODS: there were studied 4,236 children (3.1-10.9y); 48.3%M:51.6%F, from four studies made in Paul nia, SP-Brazil. Height, weight and TSF (Holtain caliper) were measured. For each children BMI was calculated and transformed in SDS, according to North American data (Frisancho, 1993). Multiple linear regression analysis (stepwise) was used for the whole population and in three groups according to BMI: A) SDS < or = -1.0; B) -1.0 < SDS< 1.0) SDS(3) 1.0. Data were processed with SPSS software. RESULTS: in group A, the TSF (7.8 +/- 2.3) variability was lower when compared with the groups B (10.1 +/- 4.0) and C (17.8 +/- 6.2). In multiple linear regression with the whole population, R = 0.478 for TSF. In groups B and C, R = 0.364 and 0.368 respectively for TSF, and in group A it was only 0.032. CONCLUSIONS: these observations demonstrated a height correlation between BMI and TSF in children with obesity risk (group C). Therefore, we conclude that, in Brazil BMI can be used for children's research of obesity in population studies, instead of TSF.

Body Mass Index↗

PubMedDate not supplied

Predictors of erythropoietin responsiveness in chronic hemodialysis patients.

The impact of dialysis intensity on erythropoietin (EPO) requirements is unclear. Previous work suggests that increased dialysis is associated with increased erythropoietin responsiveness (ERSP), but average dialysis intensity has increased since those publications. We hypothesized that ERSP would be independent of delivered Kt/V(urea) at current intensities of hemodialysis. We prospectively studied 135 stable chronic hemodialysis patients who receive iron and subcutaneous EPO dosed according to current guidelines. We collected biochemical, hematologic, and single pool urea kinetics data. ERSP was expressed as units per kilogram per week of EPO administered. Simple and multiple linear regression were used to identify characteristics predictive of ERSP. The mean age of the patients was 62 +/- 17 years (range, 17-90 years); 68 of 135 (50.3%) were women, and 120 of 135 (88.9%) were Caucasian. Mean delivered Kt/V(urea) was 1.60 +/- 0.49, with 102 of 135 (75.6%) of patients with a delivered Kt/V(urea) > 1.3. Univariate linear regression showed seven significant independent predictors of erythropoietin requirements. Low serum albumin (p < 0.001), low serum calcium (p = 0.002), high serum phosphate (p = 0.004), and high serum iPTH (p = 0.007) were all associated with lower levels of ERSP. Lower ERSP was also correlated with lower hemoglobin and lower serum iron and transferrin saturation. Delivered dialysis (Kt/ V(urea)) was not a significant predictor of ERSP (p = 0.61). Multivariate regression confirmed low serum albumin (p < 0.01), high serum phosphate (p = 0.001), high immunoreactive parathyroid hormone (p = 0.025), and low transferrin saturation (p < 0.0005) as predictors of low ERSP, and also found high serum ferritin to be correlated with low ERSP (p = 0.016). We found no relationship between erythropoietin responsiveness and intensity of hemodialysis in this population of patients with a mean delivered Kt/V(urea) of 1.6. This may indicate a threshold effect beyond which more dialysis will not improve ERSP. However, markers of an underlying inflammatory state and of secondary hyperparathyroidism were associated with decreased response to erythropoietin.

Adolescent↗

PubMed2000

Rate of visual field loss in progressive glaucoma.

OBJECTIVE: To investigate the rate of visual field (VF) loss in progressive glaucoma. SETTING: Outpatient department, nonreferral base. METHODS: A cohort of 34 patients with normal-pressure glaucoma (NPG), 68 patients with primary open-angle glaucoma (POAG), and 125 patients with ocular hypertension (OHT) were followed up for an average of 9 years. Visual fields were obtained annually with automated perimetry. The rate of VF loss as a percentage per year was calculated. RESULTS: Twenty-three eyes with NPG, 31 with POAG, and 10 with OHT showed progression of VF loss. The mean (+/-SD) rates of VF deterioration were 3.7%+/-3.3% per year in NPG, 2.5%+/-1.8% in POAG, and 2.3%+/-1.3% in OHT converting to POAG, and did not differ significantly. No difference in the rate of VF loss was found between eyes with and without optic disc hemorrhages (2.7%+/-2.9% and 3.1%+/-2.1%, respectively). The rate of VF loss was not related to the initial VF status. The rate of VF loss between the superior and inferior hemifields was correlated in patients with NPG (r(s) = 0.67, P = .04). Comparison of visual field loss with linear regression analysis showed significant slopes in only 37.5% of eyes with progression, which had a progression rate of 4.2%+/-3.0%. CONCLUSIONS: The rate of VF loss did not differ between patients with NPG and POAG. The rate of deterioration was related neither to initial VF status nor to the presence of disc hemorrhages. Linear regression is applicable only in a portion of the patients who have progression of VF loss.

Aged↗

PubMed1984

Statistical evaluation of inter- and intra-laboratory variations of the Ames test, as related to the genetic stability of Salmonella tester strains.

A statistical analysis was performed on the data resulting from an international collaborative study of the Ames test according to a standardized experimental protocol, which involved the comparative testing of 4NQO (4 doses), in 3 separate experiments for each of the 38 participating laboratories, by using a common reference (R) culture and in-house laboratory (L) cultures of 5 strains of S. typhimurium. Despite some toxicity phenomena recorded at the highest dose of 4NQO, the majority of the dose-response curves in individual laboratories were linear on a bi-log scale and their mean values fitted a linear regression framework. Scattering of data around mean values of laboratories was Gaussian-like even at the highest dose of 4NQO, toxic effects being expressed as a dose-related increase of variance. A weighted least-square analysis could therefore take into account toxic effects without resorting to a sophisticated non-linear model incompatible with log transformation. Various analytical approaches--e.g. the weighted estimates of linear regression parameters, a multifactor (laboratory, experiment, dose, culture of each strain) analysis of variance with all the possible interactions, the assessment of correlations in individual laboratories and of coefficients of variation for induced and spontaneous mutability--could detect some statistically significant differences between L and R cultures. However, at a critical evaluation on an individual basis, only few of these differences, without any peculiar involvement of given strains, were convincing in view of the existence of real phenomena of genetic drift. Therefore, on the whole, the genetic drift of Salmonella tester strains appears to lend a negligible contribution to the considerable inter- and intra-laboratory variability detected in this study. With a background variability between replications averaging 26%, a dose-related variability was evident both between experiments (28-54%) and between laboratories (44-127%).

4-Nitroquinoline-1-oxide↗

PubMed1976

Changes in composition and metabolic activity of the skeletal parts of the extremity of the adult rat following below-knee amputation.

Below-knee amputation in adult male rats resulted in characteristic quantitative and qualitative changes of the tibia stump and of the femur in the amputated leg. These changes were followed for periods of 1 to 32 weeks after the amputation. The femur of the amputated leg underwent a significant reduction of its total bone mass and a significant decrease of its percentage ash content, whereas its percentage water and organic contents increased significantly. The bone specific activity was initially decreased and began to increase after the 10th week post surgery with a positive linear regression. The amputated tibia underwent a significant, though declining, increase of its percentage water and organic contents and a likewise significant decrease of its percentage ash content. The specific activity of the amputated tibia was significantly higher than that of the tibia from the non-amputated leg, the difference showing a negative linear regression. The specific activity of the femur was decreased initially and increased later on.

Amputation, Surgical↗

PubMed1999

[Variability in resource utilization in primary care].

OBJECTIVE: To measure variability in the use of primary care resources and identify factors that explain the differences. DESIGN: An ecological observation study. SETTING: Primary care. PARTICIPANTS: The 1996 index of frequency of attendance was chosen as the indicator of primary care resource use throughout the territory managed by INSALUD. INTERVENTIONS: The analysis was conducted on a provincial basis, using the statistical technique of multiple linear regression. The index of frequency of attendance was chosen as dependent variable; and demographic, social and economic, mortality, organisation, and offer and accessibility indicators were chosen as explanatory or independent variables. MEASUREMENTS AND RESULTS: There was wide variability in frequency of attendance in the areas managed by INSALUD during 1996, with a variation coefficient of 20.5%. The simple linear regression analysis showed that the population's income explained 55% of variability. Income, the number of doctors per 1,000 inhabitants and the percentage of children under 3 explained 70% of the variability of frequency of attendance at primary care. CONCLUSIONS: There are differences between provinces in primary care health resource use. Attendance for primary care consultation in INSALUD is more frequent in provinces with a low social and economic level, more doctors per 1000 inhabitants and more children under 3.

Age Factors↗

PubMed2000

Effects of hospital policies based on 1996 group B streptococcal disease consensus guidelines. The Active Bacterial Core Surveillance Team.

OBJECTIVE: To determine whether the 1996 consensus guidelines for prevention of early-onset group B streptococcal disease developed by the Centers for Disease Control and Prevention, ACOG, and the American Academy of Pediatrics are affecting obstetric practice and disease occurrence. METHODS: Personnel in hospitals with obstetric services in seven surveillance areas completed surveys about their programs, patient populations, and group B streptococcal disease prevention policies. Survey results were linked to group B streptococcal disease cases identified by active surveillance in 1996 and 1997. An early onset case was defined as a case in which group B streptococci were isolated from a sterile site in the 1st 6 days of life. The number of cases in 1996 and 1997 were compared using a paired t test. Linear regression was used to assess hospital characteristics associated with group B streptococcal disease cases. RESULTS: Of 177 hospitals, 165 (93%) responded, and 96 (58%) of those had group B streptococcal disease prevention policies. Hospitals that established or revised their policies in 1996 had a lower mean number of cases in 1997 than in 1996 (0.58 versus 1.29, P = .006). Linear regression analysis, controlling for number of births, indicated that a hospital's having more black mothers and location in particular states were associated with more cases of disease. Citing the 1996 ACOG reference as the source for hospital group B streptococcal disease prevention policy was associated with fewer cases of group B streptococcal disease (P = .038). CONCLUSION: The publication and adoption of the guidelines were associated with decreasing occurrence of group B streptococcal disease.

Guideline Adherence↗

PubMed2000

Direct impact of non-fatal occupational injuries.

OBJECTIVE: The objectives of this study were to describe the pattern of certain direct impacts of non-fatal injuries among workers insured by the General Organization of Social Insurance, admitted to hospitals in Al-Khobar City, and to determine factors influencing these direct impacts. METHODS: This cohort study consisted of 65, 915 insured male workers in various industries, followed to determine those who were admitted to 2 private hospitals selected randomly in Al-Khobar City. A data-collection sheet was used to collect the necessary data from patients and their medical records on admission to the hospital. RESULTS: The majority of admissions (78%) were for periods of less than a week. Absence from work was longer than 3 weeks in 35.5% and shorter than 1 week in 25% of admissions. The majority of the cases (65%) visited clinics from 2 to 7 times. Direct medical cost per admission was less than SR2,000 in 64% of the cases in one of the hospitals (one United States dollar = 3.75 Saudi Riyals). Multiple linear regression analysis for period of absence from work, length of hospitalization, and number of clinic visits showed these direct impact variables to be inter-related. Injury outside the work place (road traffic accidents), and the hospital which the injured worker was referred to, were the other main risk factors determining the direct impact of the injury. Multiple linear regression for direct medical cost was positively associated and predicted by the younger age of the worker. CONCLUSIONS: The direct impact of occupational injuries in this study, though less than the same reported from Western countries, were responsible for significant medical charges, human suffering and loss of productivity. Efforts made by different industries to prevent occupational injuries should be encouraged and continued, and the General Organization of Social Insurance may monitor their success by conducting similar studies.

Absenteeism↗

PubMed2002

Clinical and demographic predictors of exercise capacity in end-stage renal disease.

Patients on maintenance hemodialysis therapy for end-stage renal disease have reduced exercise tolerance. Multiple processes related to uremia and hemodialysis have been implicated in the pathophysiology of this impairment. However, limited data are available to identify the separate and combined effects of clinical factors on the degree of impairment for individuals within this population. For this purpose, data from 193 patients who had undergone exercise testing for two clinical trials were retrospectively analyzed. Univariate and multiple linear regression analyses were used to identify demographic and clinical correlates of peak exercise oxygen uptake (VO2). Peak VO2 averaged 18.5 +/- 6.4 mL/min/kg. On univariate analysis, peak VO2 correlated positively with male sex and hemoglobin, serum albumin, and serum creatinine concentrations and correlated negatively with dialytic age and diagnosis of diabetes or chronic heart failure. In a multiple linear regression model, sex, hemoglobin concentration, age, and diagnosis of diabetes each remained statistically significant. Together, factors included in the model accounted for 41% of the variability in peak VO2 (P = 0.0001). Among factors not correlating significantly with peak VO2 were resting blood pressure, serum carnitine level, and urea clearance assessed by Kt/V. Findings show the range of exercise impairment among clinically stable ambulatory hemodialysis patients, which may be sufficient to interfere with normal daily activities for many of these patients. Although this impairment may be broadly attributable to physiological consequences of uremia, the degree of impairment for individual patients is predicted by demographic factors, coexistent disease, and factors potentially modified by medical therapeutics.

Adult↗

PubMed2006

Addressing glucose sensitivity measured by F-18 FDG PET in lung cancers for radiation treatment planning and monitoring.

PURPOSE: To address glucose sensitivity in lung cancers before and after radiation treatment (Tx). METHODS AND MATERIALS: Twelve patients were each studied with two pre-Tx positron emission tomography (PET) scans and 3 patients each with one post-Tx PET scan, with glucose concentration [Glc] and maximum standard uptake value (SUV) recorded. The pre-Tx glucose sensitivity, g from SUV1/SUV2= {[Glc]1/[Glc]2}g and Tx index, tau from SUVpost-Tx/SUVpre-Tx = {[Glc]post-Tx/[Glc]pre-Tx}tau was calculated by linear regression. Pre-Tx SUVs were corrected to post-Tx Glc with g (SUV'pre-Tx) for a pure Tx effect, R = ln(SUVpost-Tx/SUV'pre-Tx). RESULTS: There were no significant differences in SUV but [Glc] were different (96.4 +/- 10.9 vs. 88.3 +/- 10.5, p = 0.015) between two pre-Tx PET scans. Linear regression yielded g = -0.79 and tau = -1.78 to -2.41 (p < 0.0005 in all). The %DeltaSUV after Tx for 3 patients without vs. with g correction were different by -12%, 0%, and + 7%, suggesting varying effects from glucose. R values were also different and mean R (-0.81 +/- 0.38) was significantly different from zero (p = 0.03), consistent with successful Tx as confirmed by clinico-radiologic follow-up. CONCLUSIONS: The extra dimension of glucose sensitivity, g besides SUV incorporated in the combined Tx-derived tau may be a useful global Tx evaluation index even with differing [Glc].

Aged↗

PubMed1992

International cooperative study on the relationship between dietary factors and blood pressure: a preliminary report from the Cardiovascular Diseases and Alimentary Comparison (CARDIAC) Study. The CARDIAC Cooperative Study Research Group.

1. To investigate the epidemiological relationship of dietary factors to blood pressure (BP) and major cardiovascular diseases, we carried out the international cooperative Cardiovascular Diseases and Alimentary Comparison (CARDIAC) Study, which so far involves 48 centers in 20 countries as of August 1991. From each population, 100 men and 100 women aged 50-54 years were randomly selected for BP measurement, 24-h urine collection, blood tests, and medical interview. Various biological markers of diets from urine and blood were analyzed centrally in the Izumo CARDIAC center. 2. Cross center analysis using simple linear regression revealed strong significant correlations of body mass index (BMI) to systolic BP (SBP; p < 0.01) and diastolic BP (DBP; p < 0.001) in men. 24-h urinary sodium (Na) excretion in men also showed significant correlations with SBP (p < 0.05) and DBP p < 0.05) even after controlling for the effect of BMI (SBP; p < 0.05, DBP; p < 0.05). 3. Within center analysis using multiple linear regression implied that BMI and Na strongly adversely affect BP, whereas magnesium may have beneficial influence on BP. 4. Multicolinearities among 24h urinary sodium, calcium, and urea nitrogen were noted in men.

Body Mass Index↗

PubMed1998

Cortical Lewy bodies and Alzheimer-type changes in patients with Parkinson's disease.

We investigated the role of cortical Lewy bodies (LB) and Alzheimer-type changes in cognitive impairment in patients with idiopathic Parkinson's disease (PD). We evaluated 44 cases for the extent of neuropathological lesions with a CERAD neuropathological assessment battery and the stage of dementia using Reisberg's global deterioration scale (GDS). Substantia nigra, amygdala, hippocampus and cerebral cortex were examined for LB and Alzheimer-type changes. For detection of LB, the cortical areas were stained with polyclonal antibodies against ubiquitin and tau. We found at least one cortical LB in 93% of cases. Furthermore, 43% of the cases had histological findings of definite Alzheimer's disease (AD). The association between cognitive impairment and the number of cortical LB and Alzheimer-type changes in the amygdala, hippocampus and six selected gyri from cerebral cortex were analyzed using stepwise linear regression. In this analysis the total number of cortical LB, and the amount of neurofibrillary tangles in the temporal cortex remained statistically significant. When the cases with neuropathological changes consistent with a diagnosis of AD were excluded, the correlation between the total number of cortical LB and cognitive impairment was more obvious. A stepwise linear regression analysis in these cases found the total number of cortical LB to be the statistically significant predictor of cognitive impairment. This study revealed that LB densities in the cortex, especially in the temporal neocortex, correlated significantly with the cognitive impairment in PD independent of or in addition to Alzheimer-type pathology.

Aged↗

PubMed1987

Factors regulating the formation of chylomicrons and very-low-density lipoproteins by the rat small intestine.

The aim of this study was to investigate how the relationship between chylomicron and very-low-density lipoprotein (VLDL) transport of fatty acid into lymph was affected by the total amount of lipid transported via the intestinal lymphatics in the rat. Two different experimental conditions were employed. First, intestinal lymph fistula rats were infused with four different levels of [3H]oleic acid (15, 30, 60 and 120 mumol per h) at a constant rate for 8 h. Lymphatic transport of [3H]oleic acid via chylomicrons and VLDLs was measured in lymph collected during the seventh h. Within the dose range studied chylomicron increased exponentially, while the output in VLDL reached a plateau at a total lymph [3H]oleic acid output of approx. 60 mumol/h. A linear regression analysis of the ln(chylomicron/VLDL) versus the total output in lymph yielded a coefficient of correlation of 0.95. Second, we utilized the fact that intraduodenal infusion of the nonionic detergent Pluronic L-81 (L-81) inhibits chylomicron transport and that this inhibition is reversed by the cessation of L-81 infusion (unblocking). A linear regression analysis of the ln(chylomicron/VLDL) versus total lymph [3H]oleic acid output during the first 4 h of unblocking gave a coefficient of correlation of 0.79. Statistical analysis of the regression equations from the two experiments showed that for the same lymphatic [3H]oleic acid output, the chylomicron/VLDL ratio was significantly lower in the L-81 experiment, indicating that the relative rates of formation of chylomicron to VLDL were different under these two experimental conditions. However, the principal pattern was the same, i.e., chylomicron production increased, while VLDL production became saturated when the amount of oleic acid transported to the lymph was increased.

Animals↗

PubMed1988

Methodologic considerations in measuring glycosylated hemoglobin in epidemiologic studies.

Multiple linear regression was used to predict an incubated glycosylated hemoglobin value from the unincubated value and blood glucose. Hemoglobin A1 (HbA1) was measured by a disposable microcolumn technique in a large, geographically defined population of diabetic persons in southern Wisconsin. During the study, incubation of blood samples to remove pre-A1c was implemented. Multiple linear regression using data from a group of 788 patients yielded the equation: incubated HbA1 = 0.897 (non-incubated HbA1)-0.00332 (blood glucose) + 0.388. This equation was "validated" by substituting the calculated value of incubated HbA1 for the actual value in a multinomial logistic regression with diabetic retinopathy as the dependent variable. Little change in the model resulted from the substitution. Further validation was obtained from an independent sample of diabetic persons. Calculated values of incubated HbA1 were an average of 0.4% lower than the actual values.

Age Factors↗

PubMed2005

Carotid artery intimal medial thickness, brachial artery flow-mediated vasodilation and cardiovascular risk factors in diabetic and non-diabetic indigenous Australians.

BACKGROUND: Indigenous Australians are at high risk for cardiovascular disease and type 2 diabetes. Carotid artery intimal medial thickness (CIMT) and brachial artery flow-mediated vasodilation (FMD) are ultrasound imaging based surrogate markers of cardiovascular risk. This study examines the relative contributions of traditional cardiovascular risk factors on CIMT and FMD in adult Indigenous Australians with and without type 2 diabetes mellitus. METHOD: One hundred and nineteen Indigenous Australians were recruited. Physical and biochemical markers of cardiovascular risk, together with CIMT and FMD were measured for all subjects. RESULTS: Fifty-three Indigenous Australians subjects (45%) had type 2 diabetes mellitus. There was a significantly greater mean CIMT in diabetic versus non-diabetic subjects (p=0.049). In the non-diabetic group with non-parametric analyses, there were significant correlations between CIMT and: age (r=0.64, p<0.001), systolic blood pressure (r=0.47, p<0.001) and non-smokers (r=-0.30, p=0.018). In the diabetic group, non-parametric analysis showed correlations between CIMT, age (r=0.36, p=0.009) and duration of diabetes (r=0.30, p=0.035) only. Adjusting for age, sex, smoking and history of cardiovascular disease, Hb(A1c) became the sole significant correlate of CIMT (r=0.35, p=0.01) in the diabetic group. In non-parametric analysis, age was the sole significant correlate of FMD (r=-0.31, p=0.013), and only in non-diabetic subjects. Linear regression analysis showed significant associations between CIMT and age (t=4.6, p<0.001), systolic blood pressure (t=2.6, p=0.010) and Hb(A1c) (t=2.6, p=0.012), smoking (t=2.1, p=0.04) and fasting LDL-cholesterol (t=2.1, p=0.04). There were no significant associations between FMD and examined cardiovascular risk factors with linear regression analysis CONCLUSIONS: CIMT appears to be a useful surrogate marker of cardiovascular risk in this sample of Indigenous Australian subjects, correlating better than FMD with established cardiovascular risk factors. A lifestyle intervention programme may alleviate the burden of cardiovascular disease in Indigenous Australians by reducing central obesity, lowering blood pressure, correcting dyslipidaemia and improving glycaemic control. CIMT may prove to be a useful tool to assess efficacy of such an intervention programme.

Adult↗

PubMed1997

Determination of gestational age in sheep and goats using transrectal ultrasonographic measurement of placentomes.

Three experiments were conducted to determine gestational age in the ewe and doe by measuring placentomes with a B-mode ultrasonograph and a 5 MHz transducer. Transrectal measurements were obtained by placing the female over a bale of hay. In Experiment 1, ewes (n = 12) and does (n = 15) were examined by transrectal ultrasonography every week from breeding to parturition to determine the growth pattern of placentomes during pregnancy. In Experiment 2, placentomes from 132 ewes and 169 does were measured between 30 and 90 d of gestation. A linear regression relationship between fetal age in days and placentome size in mm was calculated and adjusted for does (gestational age = 28.74 + 1.80PL + e, r(2) = 70.34) and for ewes (age = 47.98 + 0.62PL + e, r(2) = 15.59). In Experiment 3, the placentomes of 63 does were measured to validate this relationship by using linear regression. Gestational age was determined correctly in 66% of the does, with a range of +/- 7 d and in 96% with a margin of +/- 14 d. In conclusion, transrectal ultrasonography allowed for the measurement of placentome size, which increased rapidly during the first 70 to 90 d of gestation in ewes and does. In ewes, however, there was a poor correlation of placentome size with gestational age, while in goats, measurement of placentomes could be used along with pregnancy diagnosis by transrectal ultrasonography as an indication of gestation age.

Journal Article↗

PubMed2001

Familial dyslipidemic hypertension syndrome: familial combined hyperlipidemia, and the role of abdominal fat mass.

Familial combined hyperlipidemia (FCHL) is the most frequent genetic lipid abnormality in humans, with a 5- to 10-fold increased risk of early myocardial infarction. Familial combined hyperlipidemia has been proposed as the leading cause of dyslipidemia in familial dyslipidemic hypertension (FDH). It was the objective of this study to quantify and analyze the simultaneous occurrence of hypertension and hyperlipidemia in FCHL families. We assessed blood pressure (BP) and hyperlipidemia in 27 families with FCHL (235 relatives and 140 spouses, aged 30 to 60 years). Hypertension was defined as a BP more than 140/90 mm Hg, or the use of antihypertensive medication. Multiple backward linear regression analysis was used to derive a biological formula describing BP in FCHL families. One-third of 27 FCHL families were diagnosed with FDH. Sixty-four of 235 (27.2%) relatives had dyslipidemic hypertension (DH), compared to 20 of 140 (14.3%) spouses (P = .005); odds ratio = 2.25 (95% confidence interval 1.29-3.91). Multiple linear regression analysis showed that age, FCHL status, and waist circumference significantly contributed to systolic blood pressure (SBP) in female FCHL relatives. In conclusion, in FCHL we defined age, waist circumference, and hyperlipidemia as predictors of SBP. This study indicates that visceral adipose tissue strongly contributes to the high prevalence of DH in FCHL families. Reduction of visceral fat should be tested as a potential therapeutic intervention for hyperlipidemia and hypertension in FCHL individuals.

Abdomen↗