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Abstract
Hypertension is the most common reversible risk factor for cardiovascular disease. It is especially common in African Americans. One of the factors that may contribute to the high rates of hypertension and target organ injury in African Americans is obesity. Hypertension and obesity are common among African Americans. Obesity is particularly common in African American women. About 75% of African American women are obese. Regulation of both body weight and blood pressure are complex, involving an interaction of genetic and environmental factors. Most research thus far has focused on blood pressure control systems studied in other forms of hypertension, including the sympathetic nervous system, the renin angiotensin system, and metabolic factors-primarily insulin resistance. Proposed mechanisms that are unique to obesity-associated hypertension include: 1) intrarenal physical forces associated with obesity-induced changes in the renal medulla; 2) genetic/metabolic factors; and 3) metabolic effects of abdominal visceral fat. The Jackson Heart Study provides a unique opportunity to address unresolved questions in the relationship of body weight, blood pressure, and cardiovascular disease.
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Jones DW, Gallimore MJ, Harris SL, Winter M. Antibodies to factor XII associated with lupus anticoagulant. Thromb Haemost 1999; 81:387-90. [PMID: 10102466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Falsely low levels of factor XII (FXII) have been documented in patients who are lupus anticoagulant positive (LA+). In addition, we have previously noted a surprisingly high incidence (20.9%) of apparently true FXII deficiency in patients who were LA+. We have hypothesised that this may be partly due to the presence of antibodies to FXII. The aim of the present study was to investigate whether LA+ patient plasmas contain antibodies directed either against FXII or FXII in association with phospholipids. Plasma samples from 60 blood donors, all LA negative, and 51 LA+ patients were tested using ELISA assays employing purified FXII, phosphatidylserine (PS) and phosphatidylethanolamine (PE). We have identified seven patients whose plasma contained either IgG or IgM that reacted with purified FXII in the absence of PS or PE. When PS was included in the assay system four additional patient plasmas were shown to contain either IgG or IgM that reacted with FXII. The plasma of one patient contained IgG that reacted with FXII both in the presence and absence of PS. There was no reactivity to FXII with either IgG or IgM when PE was included in the assay system. Affinity purified IgG from three patients whose plasma reacted with FXII in the ELISA assay in the absence of PS, gave a positive reaction in an immunoblot assay. These results suggest that FXII antibodies are present in a significant proportion of LA+ patients and may lead to an erroneous diagnosis of FXII deficiency.
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Jones DW. Exposure or absorption and the crucial question of limits for mercury. JOURNAL (CANADIAN DENTAL ASSOCIATION) 1999; 65:42-6. [PMID: 9973766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
Health Canada recently lowered the recommended maximum daily exposure of mercury from all sources for women of child-bearing age and for children less than 10 years. This new exposure guideline does not seem to be based on any new scientific finding of human toxicity. The average daily intake of methylmercury (mainly from fish) that may cause demonstrable health effects in the most sensitive individual is 300 micrograms/day, or 4.3 micrograms Hg/day/kg body weight. The new, lower Health Canada limit is 95% below the level that may cause health effects. A number of studies have looked at methylmercury in human breast milk (where maternal consumption of fish is high), but no strong evidence of toxicity has been reported. The amount of mercury released from dental amalgam is minimal; a person would have to have 490 amalgam surfaces for there to be enough mercury vapour and ionic mercury given off from amalgam fillings to meet the maximum exposure guidelines. The uptake of food-related organic mercury is six times higher than the uptake of mercury from amalgam; moreover, food-related mercury is significantly more toxic. Many studies of amalgam-related mercury are flawed by confusion between exposure and absorption for the various forms of mercury, a limited selection of data, the ignoring of confounding variables or the misclassification of data.
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Chefer SI, Horti AG, Lee KS, Koren AO, Jones DW, Gorey JG, Links JM, Mukhin AG, Weinberger DR, London ED. In vivo imaging of brain nicotinic acetylcholine receptors with 5-[123I]iodo-A-85380 using single photon emission computed tomography. Life Sci 1998; 63:PL355-60. [PMID: 9870715 DOI: 10.1016/s0024-3205(98)00514-1] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The distribution and kinetics of 5-[123I]iodo-A-85380, a novel ligand for brain nicotinic acetylcholine receptors (nAChRs), were evaluated in the Rhesus monkey using single photon emission computed tomography (SPECT). Peak levels of radioactivity were measured in brain at 90 min after injection of the tracer. Accumulation of radioactivity was highest in the thalamus, intermediate in the frontal cortex and basal ganglia, and lowest in the cerebellum. The ratio of specific to nonspecific binding (V3") in the thalamus, estimated from the (thalamic-cerebellar)/cerebellar radioactivity ratio, reached a value of 6 at 4 h post-injection. Specific binding was reduced by subcutaneous injection of 1 mg/kg cytisine at 2.25 h after injection of radiotracer. At 2.5 h after cytisine administration, radioactivity in the thalamus was reduced by 84%, in the frontal cortex, by 76%, and in the basal ganglia, by 57% of the level measured at the time of cytisine administration, demonstrating that the binding was reversible. On the basis of these findings, together with other data indicating high affinity, receptor subtype selectivity, low nonspecific binding and lack of toxicity in animals, 5-[123I]iodo-A-85380 appears to be a promising ligand for SPECT imaging of nAChRs in the human brain.
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Jones DW. Dental cements: a further update. JOURNAL (CANADIAN DENTAL ASSOCIATION) 1998; 64:788-9. [PMID: 9879142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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Jones DW. Dental composite biomaterials. JOURNAL (CANADIAN DENTAL ASSOCIATION) 1998; 64:732-4. [PMID: 9854362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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Woolf-May K, Kearney EM, Jones DW, Davison RC, Coleman D, Bird SR. The effect of two different 18-week walking programmes on aerobic fitness, selected blood lipids and factor XIIa. J Sports Sci 1998; 16:701-10. [PMID: 10189075 DOI: 10.1080/026404198366335] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Forty-nine previously sedentary or low active individuals aged 40-71 years were allocated to three groups. The long walking group participated in an 18-week walking programme which consisted of walks lasting 20-40 min; the repetitive short walking group completed walks of between 10 and 15 min, up to three times a day, with no less than 120 min between each walk; and the control group maintained their low level of activity. Both walking programmes began at a prescribed 60 min x week(-1), which increased steadily up to 200 min x week(-1) by week 12. During the study, the long walking group walked for an estimated 2514 min (139 min x week(-1)), expending an estimated 67.5 MJ (3.72 MJ x week(-1)) at an estimated 73% of their age-predicted maximum heart rate and 68% of their estimated VO2max. The repetitive short walking group walked for an estimated 2476 min (135 min x week(-1)), expending an estimated 58.5 MJ (3.17 MJ x week(-1)) at an estimated 71% of their age-predicted maximum heart rate and 65% of their estimated VO2max. The results showed a statistically significant reduction in heart rate during a standardized step test (pre- vs post-intervention) in both walking groups, indicating an improvement in aerobic fitness, although the control group showed a higher average heart rate during the post-intervention test, indicating reduced fitness. When compared with the male subjects pre-intervention, the females possessed more favourable levels of high-density lipoprotein (HDL) cholesterol (P< 0.001), apolipoprotein (apo) AI (P < 0.001) and ratios of total cholesterol:HDL cholesterol (P< 0.02) and low-density lipoprotein (LDL) cholesterol: HDL cholesterol (P< 0.02). Compared with the controls post-intervention, the walking groups showed no statistically significant changes in total cholesterol, LDL cholesterol, HDL cholesterol, apo AI, apo AII, apo B, or the ratios of total cholesterol: HDL cholesterol, LDL cholesterol: HDL cholesterol, apo AI: apo B or apo AI: apo AII (P > 0.05). Relative to the walking groups, factor XIIa increased in the control group (P < 0.05). We conclude that, although both walking programmes appeared to improve aerobic fitness, there was no evidence of improvements in the blood lipids or associated apolipoproteins of the walking groups. Further analysis indicated that this apparent lack of change may have been related to the subjects' relatively good pre-intervention blood lipid profiles, which restricted the potential for change. The implications of the observed changes in the coagulation/fibrinolytic factors remain unclear.
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Heinz A, Ragan P, Jones DW, Hommer D, Williams W, Knable MB, Gorey JG, Doty L, Geyer C, Lee KS, Coppola R, Weinberger DR, Linnoila M. Reduced central serotonin transporters in alcoholism. Am J Psychiatry 1998; 155:1544-9. [PMID: 9812115 DOI: 10.1176/ajp.155.11.1544] [Citation(s) in RCA: 198] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Dysfunction of monoamine uptake mechanisms has been implicated in the pathogenesis of alcohol dependence. The authors explored whether serotonergic dysfunction is associated with anxiety and depression, which increase the risk of relapse in alcoholics. METHOD The availability of serotonin and dopamine transporters in 22 male alcoholics and 13 healthy male volunteers was measured with the use of [123I] beta-CIT and single photon emission computed tomography, and psychopathological correlates were assessed. RESULTS A significant reduction (a mean of about 30%) in the availability of brainstem serotonin transporters was found in the alcoholics, which was significantly correlated with lifetime alcohol consumption and with ratings of depression and anxiety during withdrawal. CONCLUSIONS The findings support the hypothesis of serotonergic dysfunction in alcoholism and in withdrawal-emergent depressive symptoms.
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Abstract
OBJECTIVE To evaluate a method for the assessment of the consistency of unset resin composite. METHODS Fourteen commercial resin composites were selected, which had a range of consistencies as assessed subjectively. The material was placed in a cylindrical mold with 8 mm diameter and 8 mm depth, and a glass rod with 4.37 mm diameter driven into the composite at 24.4 mm min-1 for 6 s, i.e., to a depth of 2.44 mm. The maximum force reached during the 6 s period was recorded, and used as a measure of consistency. RESULTS Consistency values ranged from 0.33 N to 31.3 N, with the highest values being found for some of the recently introduced 'packable' materials. The reliability of the test was high. SIGNIFICANCE The test may be useful as a standard method of assessing resin composite consistency.
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Jones DW. A brief overview of dental ceramics. JOURNAL (CANADIAN DENTAL ASSOCIATION) 1998; 64:648-50. [PMID: 9812434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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Heinz A, Knable MB, Wolf SS, Jones DW, Gorey JG, Hyde TM, Weinberger DR. Tourette's syndrome: [I-123]beta-CIT SPECT correlates of vocal tic severity. Neurology 1998; 51:1069-74. [PMID: 9781531 DOI: 10.1212/wnl.51.4.1069] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To examine in vivo the density of brain monoaminergic transporters in Tourette's syndrome (TS). BACKGROUND TS is a heritable neuropsychiatric disorder characterized by chronic vocal and motor tics and is often associated with obsessive-compulsive symptoms. Hyperstimulation of dopamine receptors and dysfunction of serotonergic transmission have been implicated in its pathogenesis, but direct evidence of involvement of these neurochemical systems has been limited. METHODS Symptom severity and the availability of presynaptic monoaminergic transporters in the basal ganglia, midbrain, and thalamus were measured using SPECT and the radioligand [I-123]2beta-carbomethoxy-3beta-(4-iodophenyl)tropane ([I-123]beta-CIT) in 10 patients with TS and in 10 age- and sex-matched normal volunteers. RESULTS A significant negative correlation was found between a measure of overall tic severity and beta-CIT binding in the midbrain (r = -0.73, p = 0.02) and the thalamus (r = -0.82, p < 0.01). When examined post hoc, these correlations were determined largely by vocal tic severity. No other significant correlations were found between symptom severity and beta-CIT binding in the striatum or cortex. CONCLUSIONS These findings indicate that serotonergic neurotransmission in the midbrain and serotonergic or noradrenergic neurotransmission in the thalamus may be important factors in the expression of TS and may suggest novel targets for treatment.
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Jones DW. Dental cements: an update. JOURNAL (CANADIAN DENTAL ASSOCIATION) 1998; 64:569-70. [PMID: 9785686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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Heinz A, Higley JD, Gorey JG, Saunders RC, Jones DW, Hommer D, Zajicek K, Suomi SJ, Lesch KP, Weinberger DR, Linnoila M. In vivo association between alcohol intoxication, aggression, and serotonin transporter availability in nonhuman primates. Am J Psychiatry 1998; 155:1023-8. [PMID: 9699688 DOI: 10.1176/ajp.155.8.1023] [Citation(s) in RCA: 134] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
OBJECTIVE Studies on brain serotonin metabolism in human and nonhuman primates have indicated that dysfunction of serotonin transmission may play a role in the biological vulnerability to dependence on alcohol. Among young men, low sensitivity to alcohol intoxication predicts subsequent alcohol abuse and dependence. METHOD The authors used single photon emission computed tomography and the radioligand [(I)123]beta-CIT ([(I)123]methyl 3beta-(4-iodophenyl) tropane-2-carboxylate) to measure the availability of serotonin transporters in 11 male rhesus monkeys, and the monkeys were genotyped for a functional polymorphism of the serotonin transporter gene. The 11 monkeys had experienced parental separation after birth; their behavior and 5-hydroxyindoleacetic acid (5-HIAA) concentrations in CSF had been assessed regularly. RESULTS In the 5-year-old monkeys, there was a significant negative correlation between beta-CIT binding to serotonin transporters in the brainstem and 5-HIAA concentrations in CSF. Animals with greater beta-CIT binding and low CSF 5-HIAA concentrations displayed greater aggressiveness and were less sensitive to alcohol-induced intoxication. The genetic constitution of the serotonin transporter promoter gene did not significantly contribute to the availability of brainstem serotonin transporters as measured by beta-CIT binding. CONCLUSIONS In adult nonhuman primates who underwent early developmental stress, variables indicating a low serotonin turnover rate were associated with behavior patterns similar to those predisposing to early-onset alcoholism among humans.
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Abstract
This article provides a view of government reaction in Canada to public concern over the use of dental amalgam. It also addresses the basis of the irrational fears the general public may have regarding the impact of external factors on their health.
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Heinz A, Knable MB, Coppola R, Gorey JG, Jones DW, Lee KS, Weinberger DR. Psychomotor slowing, negative symptoms and dopamine receptor availability--an IBZM SPECT study in neuroleptic-treated and drug-free schizophrenic patients. Schizophr Res 1998; 31:19-26. [PMID: 9633833 DOI: 10.1016/s0920-9964(98)00003-6] [Citation(s) in RCA: 76] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Anhedonia and psychomotor slowing in schizophrenia have been attributed to a dysfunction of dopaminergic neurotransmission. To differentiate between disease and drug-induced negative symptoms, we examined eight drug-free and eight neuroleptic-treated schizophrenic patients. Positive and negative symptoms and extrapyramidal side effects were assessed using standardized rating scales (PSAS, AMDP, SANS). 'Reaction time' and 'motor speed' were measured using a computer-aided system and striatal dopamine D2/D3 receptor availability was assessed using [I-123]IBZM SPECT. Psychomotor reaction time, parkinsonism, affective flattening and avolition were increased in treated patients relative to the untreated cohort and were negatively correlated with dopamine D2/D3 receptor availability. Significant positive correlations were found between parkinsonism and affective flattening and between psychomotor slowing and avolition. Positive symptoms were not significantly associated with striatal IBZM binding. These findings support the hypothesis that neuroleptic-induced dopamine D2/D3 blockade in the striatum can mimic certain negative symptoms, such as affective flattening and avolition, and indicates that psychomotor testing may be helpful in differentiating between disease and drug-induced negative symptoms.
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Jones DW, Gallimore MJ, Winter M. An automated chromogenic peptide substrate assay for coagulation factor XII. Blood Coagul Fibrinolysis 1998; 9:183-7. [PMID: 9622217 DOI: 10.1097/00001721-199803000-00010] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We have developed an automated chromogenic peptide substrate assay for factor XII (FXIIcs) on a Cobas Mira S Plus clinical chemistry analyser using a new commercially available kit. This was used to determine factor XII (FXII) levels in plasma samples from 320 blood donors, 206 patients with a history of venous thrombosis and 74 lupus anticoagulant positive (LA+) patients. Results were compared with those obtained in a clotting assay for FXII (FXIIct) and an immunochemical assay (FXIIag). A satisfactory correlation coefficient of 0.92 and a regression line equation of y = 7.898 + 0.871x was obtained between FXIIcs and FXIIct in the 320 blood donors. Levels of FXII below the calculated normal range were found in nine blood donors (2.8%) and 16 venous thrombosis patients (7.8%). The blood donors and patients with venous thrombosis with low FXIIcs values had FXII levels below our lower limits of normal for both FXIIct and FXIIag; all were lupus anticoagulant negative. When FXII levels were determined in the 74 LA+ patients, 27 (36.5%) gave markedly lower FXII values in the FXIIct when compared with the FXIIcs. FXIIag levels corresponded with FXIIcs. The automated FXIIcs assay is therefore lupus anticoagulant insensitive and allows us to measure FXII levels accurately and routinely in large numbers of patient samples.
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Gallimore MJ, Jones DW, Winter M. Factor XII determinations in the presence and absence of phospholipid antibodies. Thromb Haemost 1998; 79:87-90. [PMID: 9459329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Factor XII (FXII) levels were determined in plasma samples from 29 normal donors, 10 patients with inherited FXII deficiency (all lupus anticoagulant [LA] negative) and 67 LA positive patients, using clotting (FXIIct), chromogenic substrate (FXIIcs) and immunochemical (FXIIag) assays. Excellent correlations were obtained in the three FXII assays with the LA negative samples and between the FXIIcs and FXIIag assays in the LA positive samples. Correlations between both the FXIIcs and FXIIag with FXIIct in the LA positive patients were poor. Of 67 LA positive samples studied, 25 (37.3%) showed lower values in the FXIIct assay; 13 (19.4%) of these patients were pseudo FXII deficient with values of FXII below the lower limit of normal. These results indicate that a diagnosis of FXII deficiency can be made inappropriately in the presence of phospholipid antibodies and that such a diagnosis should not be made by FXIIct assay alone.
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Jones DW, Gallimore MJ, Winter M. Factor XII determinations and lupus anticoagulants. Blood Coagul Fibrinolysis 1997; 8:531-2. [PMID: 9491272 DOI: 10.1097/00001721-199711000-00008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Carter ND, Jenkinson TR, Wilson D, Jones DW, Torode AS. Joint position sense and rehabilitation in the anterior cruciate ligament deficient knee. Br J Sports Med 1997; 31:209-12. [PMID: 9298555 PMCID: PMC1332521 DOI: 10.1136/bjsm.31.3.209] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Impaired joint position sense (JPS) has been shown in anterior cruciate ligament (ACL) deficient and osteoarthritic knees. The relation between JPS and function is uncertain. The aim of this study was to determine further if ACL deficient knees show abnormal JPS and the effect of exercise therapy on JPS, and also to assess the relation between JPS, functional stability, and strength. METHODS Fifty patients (46 men and four women, mean age 26.3 years) with unilateral ACL deficient knees were assessed on admission and after rehabilitation (5 hours a day for four weeks). JPS was assessed by reproduction of passive positioning using a visual analogue incorporating a goniometer. Knee stability was analysed by self report questionnaire (score 0-280) and functional activity test (single leg hop and figure of eight run). Isokinetic dynamometry was performed to evaluate quadriceps and hamstring peak torque strength. Controls were either age and sex matched individuals or the contralateral knee. Statistical analysis was by Wilcoxon signed rank test and Spearman rank order correlation coefficient. RESULTS JPS was impaired in ACL deficient knees. The mean (SD) errors in reproducing angles were 9.4 (3.1) degrees and 7.1 (2.3) degrees for the ACL deficient knee and control knee respectively (P < 0.0005). There was no improvement in JPS after rehabilitation (9.4 (3.1) degrees and 8.5 (3.2) degrees before and after rehabilitation respectively, P = 0.14). There was improvement as ascertained from the questionnaire (on admission 202 (32.1), after rehabilitation 243 (25.4), P < 0.0001) and functional activity testing (hop: on admission 148.7 (37.3) cm, after rehabilitation 169.8 (31.1) cm, P < 0.0005; figure of eight: on admission 48.4 (16.6) seconds, after rehabilitation 41.6 (3.4) seconds, P < 0.0001). Quadriceps strength improved (peak torque on admission 198.5 (58.9) Nm, after rehabilitation 210.5 (54.2) Nm, P < 0.05), but not hamstring strength (peak torque on admission 130.6 (28.1) Nm, after rehabilitation 135.5 (27.7) Nm, P = 0.24). JPS did not correlate with the functional activity tests (hop and figure of eight run), the responses to the questionnaire, or strength. There was no correlation between the responses to the questionnaire and functional activity tests or muscle strength. CONCLUSIONS JPS was impaired in ACL deficient knees. Although knee stability improved with exercise therapy, there was no improvement in JPS. The role of JPS in the stability of ACL deficient knees remains unclear.
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Kulynych JJ, Luevano LF, Jones DW, Weinberger DR. Cortical abnormality in schizophrenia: an in vivo application of the gyrification index. Biol Psychiatry 1997; 41:995-9. [PMID: 9129779 DOI: 10.1016/s0006-3223(96)00292-2] [Citation(s) in RCA: 78] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
To investigate the hypothesis that patients with schizophrenia exhibit gross cortical abnormalities of developmental origin, we utilized the gyrification index (GI) (ratio of inner to outer cortical contours), a measure of overall cortical folding, in an in vivo magnetic resonance imaging study of young, strongly right-handed male patients and controls. The two groups did not differ with respect to whole-brain volume, age, or handedness. In an examination confined to the left hemisphere, mean GI values were significantly reduced in the patient group in both anterior and posterior regions. Neither age nor length of illness were found to be significant predictors of GI variance in the patients group, suggesting that GI reductions do not result from an ongoing atrophic process. Rather, these results are consistent with the hypothesis of neurodevelopmental abnormalities in schizophrenia that result in an overall reduction in cortical folding.
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Jones DW, Charlton A. Traders' views on sale of cigarettes to children. BMJ (CLINICAL RESEARCH ED.) 1997; 314:1047. [PMID: 9112872 PMCID: PMC2126439 DOI: 10.1136/bmj.314.7086.1047a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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Heinz A, Jones DW, Gorey JG, Knable MB, Lee KS, Saunders RC, Weinberger DR. Analysis of the metabolites of [I-123] beta-CIT in plasma of human and nonhuman primates. Synapse 1997; 25:306-8. [PMID: 9068129 DOI: 10.1002/(sici)1098-2396(199703)25:3<306::aid-syn10>3.0.co;2-u] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
[I-123] beta-CIT is a single photon emission computed tomography (SPECT) radioligand that has been used for in vivo studies of the dopamine and serotonin transporters. Two metabolite peaks of beta-CIT have been observed by high performance liquid chromatography (HPLC), but neither has been chemically identified. One major metabolite is clearly hydrophilic. Previous reports have not agreed on the amount of the second metabolite and the extent to which it may cross the blood-brain barrier. To clarify this controversy, we have studied beta-CIT metabolites using a protein precipitation method and an organic extraction method followed by HPLC separation. Plasma from both human and nonhuman (rhesus) primates was analyzed. Concentrations of the second metabolite were substantially lower in rhesus than in human for nearly equal parent concentrations. Furthermore, in rhesus the second metabolite is partially soluble in the organic solvent ethyl acetate, whereas in human it is essentially insoluble. These observations account for the contradictions in the literature. The hydrophilic nature of the human metabolite renders it unlikely that it crosses the blood-brain barrier in sufficient quantities to interfere with the quantitative assessment of dopamine transporter densities.
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Jones DW. Pennsylvania hospital continues to reduce seclusion and restraints. JOINT COMMISSION PERSPECTIVES. JOINT COMMISSION ON ACCREDITATION OF HEALTHCARE ORGANIZATIONS 1997; 17:17. [PMID: 10177139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Haverford State Hospital in Haverford, Penn, was one of three hospitals profiled in case studies of organizations that have made efforts to reduce their use of seclusion and restraints in the January/February 1996 issue of Perspectives. As a result of this article, the hospital received numerous requests for assistance and information about its practices from other health care organizations. Haverford State Hospital is a 300-bed inpatient care facility for the seriously and persistently mentally ill. During 1996, it continued its efforts to reduce the use of seclusion and restraints. In this On Site column, David W.P.Jones, assistant superintendent for quality assurance and risk management at Haverford State Hospital, shares information on the hospital's progress and provides some additional data.
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Bartley AJ, Jones DW, Weinberger DR. Genetic variability of human brain size and cortical gyral patterns. Brain 1997; 120 ( Pt 2):257-69. [PMID: 9117373 DOI: 10.1093/brain/120.2.257] [Citation(s) in RCA: 263] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The development of the primate brain is determined by an interaction of genetic programmes and environmental events. We examined quantitatively the contribution of each of these factors to adult human brain hemisphere volume and global cortical gyral patterns by comparing 3-D MRI renderings of brains of 10 pairs of monozygotic (MZ) and nine pairs of same-sex dizygotic (DZ) twins. Brain volume was highly correlated in MZ pairs [unbiased intraclass correlation coefficient, ICC(U) = 0.95, P < 0.00001], but not in DZ pairs [ICC(U) = 0.35, P = 0.09]. Structural equation modelling indicated a 94% heritability of brain volume. Gyral patterns appeared visually more similar in MZ than in DZ pairs. This was confirmed statistically by a cross-correlation analysis of rendered images of lateral and mesial cortical surfaces. MZ twins exhibited significantly greater similarity than did DZ twins in comparisons of gyral patterns; DZ twins were not more alike than unrelated pairings. Ipsilateral hemispheres were significantly more alike than contralateral hemispheres within MZ pairs, but not within DZ pairs. Contralateral hemispheres within an individual were more alike than contralateral hemispheres between twins in the DZ pairs, but not in the MZ pairs. Heritability for gyral-sulcal patterns, as reflected in the cross-correlation data, was low and ill defined. These results indicate that human cerebral size is determined almost entirely by genetic factors and that overall cortical gyral patterns, though significantly affected by genes, are determined primarily by nongenetic factors.
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Whelton PK, Kumanyika SK, Cook NR, Cutler JA, Borhani NO, Hennekens CH, Kuller LH, Langford H, Jones DW, Satterfield S, Lasser NL, Cohen JD. Efficacy of nonpharmacologic interventions in adults with high-normal blood pressure: results from phase 1 of the Trials of Hypertension Prevention. Trials of Hypertension Prevention Collaborative Research Group. Am J Clin Nutr 1997; 65:652S-660S. [PMID: 9022561 DOI: 10.1093/ajcn/65.2.652s] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Phase 1 of the Trials of Hypertension Prevention was conducted in 2182 adults, aged 35-54 y, with diastolic blood pressure of 80-89 mm Hg to test the feasibility and blood pressure-lowering effects of seven nonpharmacologic interventions (weight loss, sodium reduction, stress management, and supplementation with calcium, magnesium, potassium, and fish oil). At 6 and 18 mo, weight loss and sodium reduction were well-tolerated and produced significant declines in systolic and diastolic blood pressures (-2.9/-2.4 and -2.1/-1.2 mm Hg for weight loss and sodium reduction, respectively, at 18 mo). None of the other interventions lowered blood pressure significantly at either the 6- or 18-mo follow-up visits. These results suggest that both weight loss and sodium reduction provide an effective means to prevent hypertension. The long-term effects of both of these interventions are being tested in phase 2 of the trial.
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