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PubMed2001

Prediction of body fat by anthropometry in older Chinese people.

OBJECTIVE: To derive regression equations for fat percentage by using simple anthropometric measurements applicable in normal and immobile (cannot stand or walk) older people. RESEARCH METHODS AND PROCEDURES: The study population comprised 352 females and 261 males, apparently well and community-dwelling, aged 69 to 82 years. Fifty-one females and 27 males were recruited for external validation. Body weight, standing height, arm span, triceps and biceps skinfold thicknesses (SFTs), and midarm circumference were measured. The reference method of total body fat percentage was dual-energy X-ray densitometry. Predictive equations for fat percentages were derived by stepwise multiple linear regression on anthropometric indices and gender. RESULTS: Upper-limb SFTs, body mass index, and gender yielded the more predictive equation. The SEE was 4.1% weight. There was a significant trend of underestimation in overweight subjects, especially in females. The equation using SFTs and midarm circumference was less reliable but more applicable to older immobile people and those with significant kyphoscoliosis. CONCLUSIONS: The combination of body mass index and upper-limb SFTs gives reliable prediction of fat percentages in older Chinese people, except in the obese.

Absorptiometry, Photon↗

PubMed2003

Gene polymorphisms, bone mineral density and bone mineral content in young children: the Iowa Bone Development Study.

We examined the association of candidate gene polymorphisms with bone mineral density (BMD) and bone mineral content (BMC) in a cohort of 428 healthy non-Hispanic white children participating in the Iowa Bone Development Study, a longitudinal study of determinants of bone accrual in childhood. BMD and BMC measurements of the hip, spine and whole body were made using a Hologic 2000 Plus densitometer in 228 girls and 200 boys ages 4.5-6.5 years. Genotypes at 14 loci representing eight candidate genes [type I collagen genes (COL1A1 and COL1A2), osteocalcin, osteonectin, osteopontin, vitamin D receptor (VDR), estrogen receptor (ER), androgen receptor (AR)] were determined. Gender-specific and gender-combined prediction models for bone measures that included age, weight, height (and gender) were developed using multiple linear regression analysis. COL1A2 and osteocalcin genotypes were identified as having the strongest and most consistent association with BMD/BMC measures. Osteonectin, osteopontin and VDR translation initiation site polymorphisms were associated with some individual bone measures, but none of the associations was as consistent as those identified for the COL1A2 and osteocalcin genes. No association was identified with COL1A1 (RsaI and Sp1), VDR (BsmI) and ER polymorphisms (PvuII, XbaI, TA) and BMD/BMC. However, we identified significant gene-by-gene interaction effects involving the ER and both VDR and osteocalcin, which were associated with BMD/BMC. Our data suggest that genetic variation at multiple genetic loci is important in bone accrual in children. Moreover, the combination of genotypes as several loci may be as important as a single genotype for determining BMD and BMC.

Anthropometry↗

PubMed2002

Affective and psychotic symptoms relate to different types of P300 alteration in depressive disorder.

BACKGROUND: Previous findings of P300 alterations in depressive disorder have been controversial. We therefore used multivariate methods to study the relationship between P300 and affective and psychotic symptoms in depressive disorder. METHODS: The P300 of 22 psychotropic drug-free depressed out-patients was registered within an auditory oddball paradigm. Affective and psychotic symptoms were evaluated using the depression and psychoticism subscales of SCL-90. The relationship of P300 amplitude and latency with affective and psychotic symptoms was assessed with multiple linear regression analysis and ANOVA. P300 values of the depressed patients were also compared with those of 22 healthy controls. RESULTS: Psychotic symptoms were associated with an overall reduction in P300 amplitude, which was pronounced in the left temporocentral electrode chain (T3, C3, Cz). Psychotic symptoms were also associated with a prolonged P300 latency. Affective symptoms were associated with a relational amplitude reduction at the right temporal scalp sites. There were no statistically significant differences in P300 amplitude or latency between depressed and control-subjects. LIMITATIONS: Rather small number of study subjects. The psychotic scores were low in all subjects. Multiple statistical analyses were used, and no specific a priori hypothesis was tested. CONCLUSIONS: In depressive disorder, affective and psychotic symptoms are associated with different types of P300 alteration, which may indicate different underlying neurobiological processes.

Adult↗

PubMed2005

Predicting in vivo soft tissue masses of the lower extremity using segment anthropometric measures and DXA.

The purpose of this study was to derive and validate regression equations for the prediction of fat mass (FM), lean mass (LM), wobbling mass (WM), and bone mineral content (BMC) of the thigh, leg, and leg + foot segments of living people from easily measured segmental anthropometric measures. The segment masses of 68 university-age participants (26 M, 42 F) were obtained from full-body dual photon x-ray absorptiometry (DXA) scans, and were used as the criterion values against which predicted masses were compared. Comprehensive anthropometric measures (6 lengths, 6 circumferences, 8 breadths, 4 skinfolds) were taken bilaterally for the thigh and leg for each person. Stepwise multiple linear regression was used to derive a prediction equation for each mass type and segment. Prediction equations exhibited high adjusted R2 values in general (0.673 to 0.925), with higher correlations evident for the LM and WM equations than for FM and BMC. Predicted (equations) and measured (DXA) segment LM and WM were also found to be highly correlated (R2 = 0.85 to 0.96), and FM and BMC to a lesser extent (R2 = 0.49 to 0.78). Relative errors between predicted and measured masses ranged between 0.7% and -11.3% for all those in the validation sample (n = 16). These results on university-age men and women are encouraging and suggest that in vivo estimates of the soft tissue masses of the lower extremity can be made fairly accurately from simple segmental anthropometric measures.

Absorptiometry, Photon↗

PubMed2006

[Myocardial remodeling and immunologic activation in patients with heart failure].

INTRODUCTION AND OBJECTIVES: Immune response-mediated regulation of myocardial collagen remains poorly understood. Our objective was to investigate the relationship between ventricular remodeling and immunologic activation in patients with heart failure (HF) by comparing dilated and ischemic cardiomyopathy. METHODS: We studied 94 patients with HF and dilated cardiomyopathy (n=46) or ischemic cardiomyopathy (n=48). We recorded left ventricular (LV) volumes, E/A ratio, and ejection fraction. Plasma concentrations of tumor necrosis factor alpha (TNFalpha), soluble TNFa receptor I (sTNF-RI), sTNF-RII, interleukin-6 (IL-6) and IL-10 were measured. The serum procollagen type-III amino-terminal propeptide (PIIINP) level was also obtained. RESULTS: Ventricular volumes were greater in the dilated cardiomyopathy than in the ischemic cardiomyopathy group (P< .05). However, sTNF-RI, sTNF-RII and PIIINP levels were higher in the ischemic group (P< .05). In this group, there were significant correlations between ventricular volumes and IL-10 and sTNF-RII levels. There was also a significant correlation between PIIINP and sTNF-RII levels (r=0.30; P< .05). In the dilated cardiomyopathy group, there was a significant correlation between ventricular volumes and IL-10 level, and between PIIINP level and IL-6 (r=0.32; P< .05) and sTNF-RII levels (r=0.32; P< .05). Multiple linear regression analysis, which included cytokine levels, age, sex and ventricular function, showed that the sTNF-RII level was an independent predictor of the PIIINP level (adjusted r(2)=0.16; P< .0001) and of ventricular volumes (LV end-systolic volume index, adjusted r(2)=0.034; P< .05; and LV end-diastolic volume index, adjusted r(2)=.048; P< .05) in both groups. CONCLUSIONS: In HF, there is an interaction between proinflammatory cytokines and the extracellular matrix. Immunologic implications vary according to disease etiology. The elevation in proinflammatory cytokine and PIIINP levels is greater in patients with ischemic cardiomyopathy. Multiple regression analysis showed that the sTNF-RII level was an independent predictor of ventricular remodeling.

Aged↗

PubMed2002

The role of early adverse experience and adulthood stress in the prediction of neuroendocrine stress reactivity in women: a multiple regression analysis.

Sensitization of stress-responsive neurobiological systems as a possible consequence of early adverse experience has been implicated in the pathophysiology of mood and anxiety disorders. In addition to early adversities, adulthood stressors are also known to precipitate the manifestation of these disorders. The present study sought to evaluate the relative role of early adverse experience vs. stress experiences in adulthood in the prediction of neuroendocrine stress reactivity in women. A total of 49 women (normal volunteers, depressed patients, and women with a history of early abuse) underwent a battery of interviews and completed dimensional rating scales on stress experiences and psychopathology, and were subsequently exposed to a standardized psychosocial laboratory stressor. Outcome measures were plasma adrenocorticotropin (ACTH) and cortisol responses to the stress test. Multiple linear regression analyses were performed to identify the impact of demographic variables, childhood abuse, adulthood trauma, major life events in the past year, and daily hassles in the past month, as well as psychopathology on hormonal stress responsiveness. Peak ACTH responses to psychosocial stress were predicted by a history of childhood abuse, the number of separate abuse events, the number of adulthood traumas, and the severity of depression. Similar predictors were identified for peak cortisol responses. Although abused women reported more severe negative life events in adulthood than controls, life events did not affect neuroendocrine reactivity. The regression model explained 35% of the variance of ACTH responses. The interaction of childhood abuse and adulthood trauma was the most powerful predictor of ACTH responsiveness. Our findings suggest that a history of childhood abuse per se is related to increased neuroendocrine stress reactivity, which is further enhanced when additional trauma is experienced in adulthood.

Adrenocorticotropic Hormone↗

PubMed2000

Influence of body composition on quantitative ultrasound parameters of the os calcis in a population-based sample of pre- and postmenopausal women.

Body mass is known to be related to measures of bone mineral density (BMD) as well as to parameters of quantitative ultrasound (US). To examine the effect of the body compartment's fat mass and lean body mass on quantitative ultrasonic bone parameters, data from a sample of 3241 German women were analyzed. Anthropometric measures, including skinfold thickness, were obtained from standardized measurements, and fat and lean body mass were derived from classical regression formulas based on skinfold measurements. Ultrasonic bone measurements were performed on the right os calcis, and speed of sound (SOS) and broadband ultrasound attenuation (BUA) were determined. Women were grouped into pre- and postmenopausal status; postmenopausal women were further stratified into ever and never hormone-replacement user. Correlation analysis indicated lean body mass to be stronger correlated with BUA than fat mass in both pre- (r = 0.23; P = 0.0001) and postmenopausal women with (r = 0.19; P = 0.0001) and without hormone replacement therapy (HRT) (r = 0.26; p = 0.0001). SOS demonstrated very small or no associations with body mass or its components. Multiple linear regression models were used to describe the relationship among body weight, fat mass, and lean body mass on BUA after adjustment for confounding variables. Both in pre- and postmenopausal women lean body mass was more strongly related to BUA than fat mass. However, body mass measures explained only small amounts of the overall variance in BUA (R(2) = 1-3% in premenopausal women; R(2) = 1% postmenopausal with HRT; R(2) = 4-5% in postmenopausal women without HRT). In conclusion, the strong influence of body mass and its components previously reported for BMD was not observed for quantitative ultrasonic bone parameters.

Adult↗

PubMed2006

Estimation of visual outcome without treatment in patients with subfoveal choroidal neovascularization in pathologic myopia.

OBJECTIVE: To clarify prognostic factors of long-term visual outcome without treatment in patients with myopic choroidal neovascularization (CNV) and estimate a regression equation to predict visual acuity at 5 years after CNV onset. METHODS: Fifty-four eyes of 54 consecutive patients with high myopia and subfoveal CNV who did not receive treatment were identified using clinical records from 1988 to 2004. Photodynamic therapy not approved for myopic CNV in Japan during this period. The association of best-corrected visual acuity (BCVA) at 5 years after CNV onset with patient age, refractive error, axial length, initial BCVA, myopic retinopathy grade, duration of persistent hemorrhage, CNV size at onset, and size of hemorrhage around the CNV was analyzed using Spearman's correlation and multiple linear regression analysis. RESULTS: BCVA at 5 years after onset was significantly associated with patient age, CNV size, and initial BCVA (P<0.05, Spearman's correlation). The regression equation estimating BCVA at 5 years after CNV onset was based on age and initial BCVA (R2=0.43). When subjects were divided into groups according to age (<40 and >or=40 years), CNV size, axial length and duration of persistent hemorrhage influenced BCVA at 5 years in patients under 40 years; while only initial BCVA was an influence in those at least 40 years old. CONCLUSIONS: We developed a linear predictive model to estimate BCVA at 5 years after onset of myopic CNV without treatment based on the identified prognostic factors. This information might be important for managing patients with myopic CNV.

Adult↗

PubMed1998

Slowing on quantitative spectral EEG is a marker for rate of subsequent cognitive and functional decline in early Alzheimer disease.

The relation between quantitative spectral electroencephalogram (qEEG) parameters and subsequent rate of cognitive, functional, and behavioral decline in 82 consecutive patients with early probable Alzheimer disease (NINCDS-ADRDA criteria) was examined in a prospective study. The qEEG was performed at initial examination and global cognitive function, activities of daily living, and behavior were assessed at initial evaluation and after a period of 6 months. Using multiple linear regression analysis, higher frontocentral and parieto-occipital theta values, lower parieto-occipital beta values, and lower peak frequency were significantly associated with more decline in global cognitive function over the follow-up period. In addition, lower parieto-occipital beta values were significantly related to more decline in activities of daily living. These associations were independent of demographic (age, sex, and education) and disease characteristics [initial Cambridge Examination for Mental Disorders of the Elderly Cognitive test (CAMCOG) or Mini-Mental State Examination scores, estimated duration of symptoms, estimated prior rate of decline, and dementia severity]. In a separate multiple logistic regression analysis, prediction of rapidly progressive decline, defined as 8 or more points decline in CAMCOG scores (n = 21), could be made with parieto-occipital and frontocentral beta values. The results suggest that slowing on qEEG is a marker for subsequent rate of cognitive and functional decline in mildly demented AD patients, independent of demographic or disease characteristics.

Activities of Daily Living↗

PubMed2006

[Insulin resistance in type 1 diabetic children and adolescents -- a simplified method of estimation].

BACKGROUND AND AIM OF THE STUDY: Our own studies confirm the hypothesis, that insulin resistance of various degree is often observed in children and adolescents with type 1 diabetes mellitus (T1DM). The knowledge of this parameter characterizing individual patients may be of great value not only for better understanding of the disease course but also as a potential source of specific treatment. Reliable estimation of insulin resistance with hyperinsulinemic euglycemic clamp is a complex, laborious and costly procedure. These facts were enough to motivate us to make an attempt to elaborate an indirect, simplified method of insulin resistance assessment in T1DM children, that would be based on patients characteristics and on clinical parameters of the disease course. MATERIALS AND METHODS: 142 children and adolescents with T1DM (79 boys, 63 girls) aged 7.7-20.3 years (mean age - 13.7+/-3.3 years) were included into the study. Duration of diabetes was 0.5-12.5 years (mean 2.7+/-2.3 years). The stage of puberty was assessed by the Tanner scale. Euglycemic-hyperinsulinemic clamp by de Fronzo was performed to estimate insulin resistance. Glucose disposal rate (M index) determined during the last 30 min of the test estimated insulin resistance. Looking for clinical and metabolic factors characterizing insulin resistance: a) the plasma cholesterol, HDL-Ch, triglycerides and HbA1c were examined, b) the height, weight, waist circumference and blood pressure were measured, c) body mass index and daily dose of insulin were calculated. For statistical analysis the multiple regression was used (forward stepwise method). RESULTS: In the study group M index ranged from 2.1 to 17.4 mg/kg/min (mean 7.27+/-2.62 mg/kg/min). The boys presented better insulin sensitivity than girls (7.79 vs. 6.62, p=0.008). The insulin resistance depended on the patients' age (r=-0.46, p<0.001) and stage of puberty (p<0.001). A correlation between M index and insulin dose (r=-0.34, p<0.05) and HbA1c (r=-0.17; p=0.04) were found. There was a significant relationship between M index and parameters of adiposity, lipids and blood pressure. All significant clinical parameters of insulin resistance were subjected to the analysis. Multiple linear regression analysis was performed. The model with the strongest correlation with index M was used to work out the formula: M index = 17.065 + 1.547 x (gender: boys=1, girls=0) - 0,183 x (age) - 0,117 x (Waist circumference) - 2,019 x (Daily insulin dose) - 0,016 x (LDL-CH) + 0,041 x (DBP). CONCLUSION: In T1DM children and adolescents it is possible to estimate for daily use extent of insulin resistance on the basis of clinical features.

Adolescent↗

PubMed2001

HIV and other predictors of serum beta-carotene and retinol in pregnancy: a cross-sectional study in Zimbabwe.

BACKGROUND: Vitamin A status during pregnancy is important to maternal and infant health. OBJECTIVE: Our goal was to identify predictors of serum beta-carotene and retinol. DESIGN: This was a cross-sectional study of 1669 women (22-35 wk of gestation) in Harare, Zimbabwe, who were receiving prenatal care. The statistical effects of age, season, gestational age, gravidity, HIV-1 infection, malaria parasitemia, and serum alpha1-antichymotrypsin (ACT) on serum beta-carotene (log10 transformed) and retinol were estimated by using multiple linear regression analyses. RESULTS: HIV infection was found in 31.5% of the women; 0.4% had malaria. Serum beta-carotene concentrations (geometric x: 0.19 micromol/L) were lower in HIV-infected women than in uninfected women (10beta = 0.78; 95% CI: 0.72, 0.84) and increased with age (10beta = 1.05; 1.02, 1.07) in gravida 1 but not in gravida > or =2 (P for interaction = 0.00002). Serum retinol (x: 0.92 micromol/L) increased with age (beta = 0.004; 0.0001, 0.008) in uninfected women but not in HIV-infected women (P for interaction = 0.02) and was 0.05-micromol/L (0.02, 0.09) lower in HIV-infected women than in uninfected women at 24 y of age. Furthermore, gestational age, season, use of prenatal supplements, and malaria were predictors of serum beta-carotene. Serum retinol was lower in women carrying male (beta = -0.04; -0.08, -0.00005) and multiple (beta = -0.21; -0.35, -0.08) fetuses. Serum ACT concentrations of 0.3-0.4, 0.4-0.5, and >0.5 g/L were associated with 3%, 11%, and 44% lower serum beta-carotene and 0.04-, 0.15-, and 0.41-micromol/L lower serum retinol. Serum ACT (g/L) was higher in women with malaria than in those without (beta = 0.10; 0.03, 0.16) and in gravida 1 than in gravida > or =2 (beta = 0.012; 0.003, 0.021), but was not higher in HIV-infected women than in uninfected women (beta = 0.001; -0.008, 0.011). CONCLUSIONS: HIV infection, malaria, gravidity, and gestational age were predictors of serum beta-carotene and retinol. Serum ACT was an important predictor of both and was associated with gravidity and gestational age.

Acute-Phase Reaction↗

PubMed2006

Association of tumor necrosis factor alpha polymorphism, but not the shared epitope, with increased radiographic progression in a seropositive rheumatoid arthritis inception cohort.

OBJECTIVE: To determine whether the tumor necrosis factor alpha (TNFA) -308 guanine-to-adenosine polymorphism and/or the shared epitope (SE) is associated with radiographic damage in patients with early rheumatoid arthritis (RA). METHODS: The cohort consisted of 189 patients with early seropositive RA (median 5.6 months since symptom onset) who had active disease, no previous disease-modifying antirheumatic drug treatment, and >or=2 sets of scored radiographs of the hands/wrists and forefeet. TNFA -308 polymorphism was analyzed by polymerase chain reaction pyrosequencing. The SE was defined as presence of any 1 of the following HLA-DRB1 alleles: *0101, *0102, *0401, *0404, *0405, *0408, *0410, *1001, *1402, or *1406. Radiographic progression was assessed by the total Sharp score. RESULTS: Using a weighted least-squares regression analysis, patients with the -308 TNFA AA plus AG genotypes (n=49) had significantly higher rates of progression in erosion scores (median 0.84 versus 0.48 units/year), joint space narrowing (JSN) scores (0.42 versus 0.04), and total Sharp scores (1.70 versus 0.61) compared with patients with the TNFA GG genotype (n=140). Presence of the SE (n=137) was associated with significantly lower progression rates (per year) for total Sharp scores (median 0.9 versus 1.25 units/year) and JSN scores (0.04 versus 0.41), but not for erosion scores (0.50 versus 0.61) compared with patients without the SE (n=52). In a least-squares multiple linear regression model, the presence of the AA plus AG genotypes was associated with a significantly higher progression rate after adjusting for the presence of the SE, interaction between the SE and the AA plus AG genotypes, baseline log C-reactive protein level, Health Assessment Questionnaire Disability Index, total Sharp score, swollen joint count, and presence of osteophytes (osteoarthritis). There was a strong linkage disequilibrium between DRB1*0301 and TNFA polymorphism (D'=0.84, r2=0.45, P<0.001). CONCLUSION: This study showed an association between the TNFA -308 polymorphism and progression of radiographic damage in patients with early seropositive RA. This association appeared to be independent of the SE, but might be dependent on other genetic variants in linkage disequilibrium with the -308 TNFA A allele and DRB1*0301. Further studies should be conducted to validate these results in both longitudinal observational cohorts and randomized clinical trials.

Arthritis, Rheumatoid↗

PubMed2005

Neuropsychological function in nondemented carriers of presenilin-1 mutations.

BACKGROUND: Prospective and case-control studies have demonstrated that memory loss and executive dysfunction occur early in Alzheimer disease (AD). OBJECTIVE: To investigate these observations by the study of persons at risk for autosomal dominant forms of AD. METHODS: Neuropsychological and genetic tests were performed on 51 nondemented at-risk members of 10 Mexican families with two distinct presenilin-1 (PS1) mutations. Test scores were compared between PS1 mutation carriers (MCs; n = 30) and noncarriers (NCs; n = 21) by analyses of variance, co-varying for family and specific mutation. Regression analyses were performed, taking into account age relative to the median age at dementia diagnosis in the family (adjusted age), gender, Beck Depression Inventory (BDI) scores, education, and number of APOE epsilon4 alleles. Subjects were divided into age tertiles and scores compared within these groups. Composite scores for Verbal Memory, Executive Function/Working Memory, Language, and Visuospatial Function were created, and these scores compared between MCs and NCs. RESULTS: MCs performed worse than NCs on the Mini-Mental State Examination, Trails Making Tests A and B, Delayed Recall of a 10-Word List, and Wechsler Adult Intelligence Scale WAIS Block Design. In multiple linear regression analyses, BDI score, gender, and number of APOE epsilon4 alleles did not consistently affect test scores. The differences seen between MCs and NCs were due to differences in the oldest tertile. MCs had lower Visuospatial and Executive Function/Working Memory but not Verbal Memory or Language composite scores. CONCLUSIONS: This study is consistent with findings in sporadic Alzheimer disease of early problems with memory, visuospatial function, and particularly with executive function in PS1 mutation carriers. Depression, gender, and presence of an APOE epsilon4 allele did not demonstrate large influences on neuropsychological performance.

Adolescent↗

PubMed2003

Factors associated with perceptions of, and decisional balance for, condom use with main partner among women at risk for HIV infection.

We examined factors associated with women's perceived advantages (pros), perceived disadvantages (cons), and decisional balance (standardized pros score minus standardized cons score) for condom use with main partner. Data from 1,938 young sexually active women who lived in five U.S. cities where the risk for human immunodeficiency virus is high were analyzed by using logistic, ordinal, and multiple linear regression analysis. For the pros scale of condom use, 27% of the women had low scores, and 33% had moderate scores. For the cons scale, 27% had moderate scores, and 5% had high scores. Of the total, 47% had a negative score on the decisional balance measure. Older age, living with a spouse or partner, or binge drinking was associated with lower pros scores and with a negative score on the decisional balance measure. Income from public assistance was associated with higher pros scores. Income from a spouse or partner or a history of sexually transmitted disease was associated with lower pros scores. Multiple sex partners or being at risk for HIV infection (based on perceptions of the main partner's behaviors) was associated with higher cons scores. Income from a job was associated with a positive score on the decisional balance measure. Our analysis identified the characteristics of women who have low pros scores, high cons scores, and negative decisional balance scores. The regression results can inform our work in HIV prevention on whether to focus on the pros, the cons, or both to obtain positive decisional balance scores and increase condom use in situations that warrant protective behaviors.

Adolescent↗

PubMed2005

[Angiogenesis and regulatory factors in rats with BPH induced by testosterone].

OBJECTIVE: To study angiogenesis and regulatory factors in the proliferated prostatic tissues of Sprague Dawley (SD) rats with BPH induced by testosterone. METHODS: Sixteen castrated SD rats, aged 8 weeks and weighing 200 approximately 250 g, were equally randomized into a model group and a control group, and the BPH model was established by subcutaneous injection of testosterone. Immunohistochemistry and MIAS (micro-image analysis system) were used to test the manifestations of MVD (microvessel density), VEGF (vascular endothelium growth factor), flk-1, endostatin, MMP-2 (matrix metalloproteinase-2) and TIMP-2 (tissue inhibitor of metalloproteinase-2) in the prostatic tissues of both the model and the control groups. Multiple linear regression with the stepwise method was adopted to analyze the data. RESULTS: The manifestations of MVD, VEGF, flk-1, MMP-2, MMP-2/TIMP-2 and VEGF/endostatin in the model group were higher, while that of endostatin was lower than in the control group (P < 0.01), and the manifestation of TIMP-2 showed no statistical difference between the two groups. The regression analysis indicated that MVD was positively correlated to VEGF, VEGF/endostatin and MMP-2/TIMP-2 (r = 0.974, 0.986, 0.982, P < 0.05) and negatively correlated to endostatin (r = - 0.975, P < 0.05) . CONCLUSION: Testosterone could induce BPH in SD rats by increasing MVD and promoting the multiplication of vascular endothelial cells after regradation of basement membrane.

Animals↗

PubMed2000

Factors influencing phenytoin-induced gingival enlargement.

AIM: To ascertain the prevalence and severity of phenytoin-induced gingival enlargement (PIGE) as well as the relationship between PIGE and risk factors. METHOD: An outpatient population of patients on phenytoin treatment and attending the epilepsy clinic at Prince Mshiyeni Memorial Hospital (PMMH) in Durban, South Africa, was requested to participate. A structured questionnaire was used to collect data on patients' demographics, social habits (e.g., drinking and smoking), dental and oral hygiene practices and medication history. Gingival enlargement, dental plaque and gingival bleeding was also measured to assess gingival health. Venous blood was collected for serum folate and phenytoin serum levels measurements. A regression analyses was then undertaken to ascertain the association between PIGE and the risk factors. Factors tested for correlation were serum phenytoin and folate levels, age, bacterial plaque, gingival inflammation, toothbrushing, smoking and alcohol consumption. The association between PIGE and the risk factors was assessed either individually, i.e., as a single entity or in combination--multifactorially. RESULTS: Of the 134 patients studied, 62% had PIGE scores > or = 1, while 8% had a PIGE score of zero. With the exception of plaque, which showed a moderate association with PIGE (r=0.4), no other factor on its own was statistically significantly related to PIGE. In the multiple linear regression analysis, factors which on their own did not have a strong influence became more important. Bacterial plaque (p=0.0001), younger age (p=0.01) and higher free serum phenytoin levels (p= 0.03), were associated with PIGE. Although known to be associated with periodontal diseases, smoking and alcohol, (p=0.03 and p=0.04 respectively), appeared to give some protection against PIGE. CONCLUSION: Risk factors associated with PIGE may have a synergistic effect. Bacterial plaque, however, appears the most important determinant of PIGE severity. This latter finding emphasises the importance of instituting a preventive plaque-control programme, particularly in young patients on phenytoin therapy.

Adolescent↗

PubMed2004

Influence of lumbosacral cerebrospinal fluid density, velocity, and volume on extent and duration of plain bupivacaine spinal anesthesia.

BACKGROUND: The current study was designed to investigate the influence of lumbosacral cerebrospinal fluid (CSF) density, velocity, and volume on the extent and duration of plain bupivacaine spinal anesthesia. METHODS: Forty-one patients scheduled to undergo orthopedic surgery with spinal block were enrolled. Lumbosacral CSF volumes were calculated from low thoracic, lumbar, and sacral axial magnetic resonance images. CSF velocity at the L3-L4 level was derived from phase-contrast magnetic resonance images. Spinal anesthesia was performed in the lateral decubitus position. CSF (2 ml) was sampled to measure CSF density before injection of 3 ml plain bupivacaine (0.5%). Statistical correlation coefficients (rho) between CSF characteristics and measurements of spinal anesthesia were assessed by Spearman rank correlation. In addition, stepwise multiple linear regression models were used to select important predictors of measures of spinal anesthesia. RESULTS: There was a significant correlation between CSF density and peak sensory block level (rho = 0.33, P = 0.034). Lumbosacral CSF volume inversely correlated with peak sensory block level (rho = -0.65, P < 0.0001) and positively correlated with onset time of complete motor block (rho = 0.42, P = 0.008). CSF volume also inversely correlated with time required for regression of the sensory block to L1 (rho = -0.35, P = 0.026) and L2 (rho = -0.33, P = 0.039). There was a significant inverse correlation between peak diastolic CSF velocity and duration of motor blockade (rho = -0.44, P = 0.005). Multiple regression analysis revealed that weight and CSF volume significantly contributed to the peak sensory block level (R2 = 0.46). CONCLUSIONS: These findings indicate that CSF density and volume influence the spread of spinal anesthesia with plain bupivacaine and that CSF volume also influences the duration of spinal anesthesia. CSF velocity might also influence the duration of plain bupivacaine spinal anesthesia.

Adult↗

PubMed1981

Regression of cardiac oxygen consumption on ventricular pressure-volume area in dog.

Left ventricular systolic pressure-volume area (PVA) has been reported to be a reliable predictor of cardiac oxygen consumption rate per beat (VO2) in a given heart with a stable inotropic background. PVA is the specific area in the pressure-volume (PV) diagram, consisting of the area (EW) within the PV loop and the area (PE) bound by the end-systolic and end-diastolic PV lines and the relaxation segment of the PV loop. EW and PE correspond to the external mechanical work and the end-systolic elastic potential energy in the ventricular wall, respectively. We determined the optimal combination of EW and PE for the best prediction of VO2, using the linear multiple regression analysis. From EW, PE, and VO2, data of many isovolumic and ejecting contractions, the optimal coefficients of EW and PE were 1.67 +/- 0.43 (SD; 7 hearts) and 1.74 +/- 0.49 (10(-5) ml O2/mmHg . ml), virtually identical to each other, corroborating that PVA, i.e., a simple sum of EW and PE, can reliably predict VO2 of a given heart in a stable contractile state.

Animals↗