Ontogeny of expression of insulin-like growth factor (IGF) and IGF binding protein mRNAs in the guinea-pig placenta and uterus

To determine the temporal and spatial distribution of insulin-like growth factor (IGF) and its family of binding proteins (IGFBPs), guinea-pig yolk sac and chorioallantoic placentae were collected at 15, 20, 25, 29, 44-45, 55 and 65-66 days of gestation. Messenger RNAs for IGF I, IGF II and IGFBP 1-6 were identified in tissue sections by in situ hybridization, using 35S-cRNA probes. Epithelial and mesenchymal cell types were identified by immunohistochemistry for cytokeratin and vimentin, respectively. At 15 days of gestation, IGF-II mRNA was expressed in ectoplacental mesoderm, cytotrophoblasts and syncytiotrophoblast, and IGFBP-5 mRNA was detected in the syncytiotrophoblast. In the mid-gestation placenta, IGFBP-5 mRNA was expressed in the marginal and interlobular syncytium and IGF-II mRNA in the labyrinth. Near term, when expansion of the labyrinth was complete, IGFBP-5 mRNA was coexpressed with IGF-II mRNA in the marginal and interlobular syncytium. These observations suggest that interaction between IGF-II and IGFBP-5 plays a role in the vascularization of the placenta by fetal vessels. IGF-II mRNA was not expressed in the maternal tissues at any gestational age. IGFBP-2, -3 and -5 mRNAs were expressed in the endometrial stroma at 7-12 days of gestation but, following establishment of the placenta, IGFBP mRNAs were more abundant in the myometrium than in the decidua. IGF-II mRNA was detected in trophoblasts invading the walls of maternal vessels, and the endothelium of the preplacental vessels expressed IGFBP-4 mRNA, while IGFBP-2 and IGFBP-5 mRNAs were present in the tunica media of mesometrial arteries that had not been invaded by trophoblast. These findings suggest that IGF-II produced by the trophoblast acts in an autocrine and/or paracrine fashion to promote trophoblast invasion and that this process is modulated by interaction with IGFBPs present in maternal tissues.

Fibrinolytic measurements in type 2 diabetic patients with acute cerebral infarction

The aim of this study was to investigate disturbances in fibrinolytic components in Type 2 diabetes patients with acute ischaemic stroke. Levels of plasminogen activator inhibitor-1 (PAI-1) activity and tissue PA (t-PA) antigen were measured in Type 2 diabetes subjects with (n=40) and without (r=80) acute stroke compared to non-diabetic subjects with (n=80) and without (n=80) acute ischaemic stroke. Diabetes was defined by WHO criteria and absence of diabetes by blood glucose <7.8 mmol(-1) and HbA(IC) <6% (reference range for assay 4.5-6.5%). Levels of t-PA antigen were lower in healthy controls (9.2 ng ml(-1) than in either stroke group (non-diabetic stroke patient: 12.6 ng ml(-1); diabetic patient with stroke: 13.5 ng ml(-1)(each at p<0.05)) and intermediate in diabetic patients without stroke (11.1 ng ml(-1), ns). In a regression model levels of t-PA were related to stroke, BMI and age but not to diabetes or sex. Diabetic subjects without stroke had higher PAI-1 activity levels than either non-diabetic group (17.7 U ml(-1) vs 12.1 U ml(-1) and 9.2 U ml(-1) (each at p<0.05)). Levels were intermediate in diabetic subjects with stroke (12.8 U ml(-1), ns). In a regression model levels of PAI-1 were related to Type 2 diabetes, female sex, and body mass index but not stroke or age. These data suggest that further suppression of fibrinolysis does not occur with ischaemic stroke in Type 2 diabetes. The findings contrast with the importance of impaired fibrinolysis in coronary artery disease previously reported in both Type 2 diabetic patients and non-diabetic subjects.

Determinants of tPA antigen and associations with coronary artery disease and acute cerebrovascular disease

The aim of this study was to determine the association of tPA antigen levels with CAD and ischaemic stroke and whether associations are independent of levels of PAI-1 antigen. In subjects with CAD (n = 247) tPA was associated with the number of coronary arteries with > or = 50% stenosis, but this association was lost after adjustment for PAI-1, which was found to be the largest determinant of tPA levels in linear regression models and accounted for as much as 38% of the variation in levels. Levels of tPA were significantly higher in patients with a history of MI compared with those without, even after adjustment for covariates and PAI-1 (MI: 10.0 [9.4-10.6] ng/ml; no MI: 8.9 [8.5-9.4] ng/ml, p = 0.004). In a logistic regression model comparing patients with MI to patients without MI, the odds ratio for tPA levels in the upper quartile compared with the lowest quartile was 2.03 (1.33-3.10). Levels of tPA in subjects with ischaemic stroke (n = 338) were significantly higher than age matched healthy control subjects (n = 366) and again this difference remained after adjustment (patients: 10.4 [9.9-10.9] ng/ml; controls: 9.0 [8.7-9.3] ng/ml, p <0.0001). In a logistic regression model comparing patients with ischaemic stroke to healthy control subjects the odds ratio for tPA in the upper quartile compared with the lowest quartile was 4.23 (3.02-5.92). These data suggest that the associations of tPA with acute thrombosis are independent of levels of PAI-1 but the mechanisms whereby enhanced fibrinolysis may predispose to thrombosis remain unclear.

Vasodilator response to exogenous adrenocorticotropic hormone in fetal adrenal cortex precedes increased steroidogenesis in sheep at 105-112 days gestation

OBJECTIVE

To examine whether the increase in adrenal cortical blood flow induced by adrenocorticotropic hormone (ACTH) is linked to steroidogenesis, or if these effects can be separated.

STUDY DESIGN

Adrenal cortical responses to ACTH were measured in ovine fetuses at 105-112 days gestation, when the adrenal is hyporesponsive. Fetuses were given an intravenous infusion of ACTH(1-24) or of vehicle. We measured regional adrenal blood flows by the microsphere technique and plasma ACTH and cortisol levels by radioimmunoassay.

RESULTS

After 3 and 24 h of ACTH infusion, plasma cortisol concentrations had risen from 2.8+/-0.8 ng/ml to 8.4+/-0.3 and 78.0+/-15.8 ng/ml (means+/-S.E.M.). Adrenal cortical blood flow increased from 108+/-25 ml/min/100 g to 319+/-33 and 518+/-51 ml/min/100 g. Plasma cortisol levels and adrenal blood flow did not change in control fetuses.

CONCLUSION

Since there was a rapid blood flow response to ACTH, despite the expected delay in the rise of plasma cortisol, we suggest that vascular responses to ACTH are not tightly linked to adrenal metabolic activity in the ovine fetus at 0.7 gestation.

Immunohistochemical identification of epithelial and mesenchymal cell types in the chorioallantoic and yolk sac placentae of the guinea-pig

To define the epithelial and mesenchymal cell types of the guinea-pig placenta, immunostaining patterns were determined for the intermediate filament proteins cytokeratin and vimentin. Chorionic and yolk sac placentae were studied at 15, 20, 25, 29-30, 44-45, 55 and 65 days of gestation. Immunohistochemistry was performed on 5-microm thick sections of paraffin embedded tissue using specific antibodies against cytokeratin, a marker for epithelial cells, including trophoblast, and vimentin, a marker for mesenchymal cells and stromal decidua. Immunostaining was identified by the avidin-biotin-peroxidase technique with diaminobenzidine as the chromogen. Most of the surface of the placenta is covered by the columnar epithelium of the parietal yolk sac, beneath which is found a layer of chorionic giant cells. In the guinea-pig, a sheet of mesenchymal cells interposed between these cell layers immunostained for vimentin, a protein that is expressed only intracellularly, and had nuclei orientated parallel to the surface of the placenta. This cell layer is quite different from Reichert's membrane in the rat or mouse, which is acellular. Within the main placenta, cytokeratin immunostaining demonstrated that the trophoblasts lining the large maternal blood sinuses are different in character from the surrounding syncytiotrophoblast, confirming earlier ultrastructural observations. In the subplacenta, some trophoblast did not immunostain for cytokeratin and there was non-specific staining of cellular debris, so that immunostaining for vimentin provided the clearest indication of the maternal-fetal interface. In later stages of gestation (30-55 days), trophoblasts invading the walls of maternal arteries immunostained for cytokeratin and were vimentin negative. In early gestation, however, trophoblast invasion of the maternal vessels was indicated by cells that were immunoreactive for both cytokeratin and vimentin.

Calibration of a reflectance pulse oximeter in fetal lambs for arterial oxygen saturations below 70%

OBJECTIVE

To calibrate a reflectance pulse oximeter developed at the Division of Perinatal Physiology, University Hospital of Zurich, for monitoring of oxygen saturations below 70%.

METHODS

Oxygen saturation measured noninvasively with the reflectance pulse oximeter in fetal sheep was compared with oxygen saturation of arterial blood samples measured by a conventional two-wavelength oximeter. Oxygen saturation was varied by stepwise reduction of the inspired oxygen concentration of the ewe.

RESULTS

A total of 58 data pairs was obtained from five fetuses, with a range of 10.9-73.5% for the reference method and 6.8-69.2% for the pulse oximetry oxygen saturation values. There was good correlation between the results obtained by the two methods (r2 = .89, P < .0001), with a 95% confidence interval of +/- 12.5%. The pulse oximeter showed a precision of 6.2% oxygen saturation.

CONCLUSION

The Zurich reflectance pulse oximeter offers valid measurements of oxygen saturation levels down to 10% oxygen saturation, and is therefore suitable for monitoring the fetus during delivery.

Platelet GP IIIa PlA and GP Ib variable number tandem repeat polymorphisms and markers of platelet activation in acute stroke

A number of polymorphisms of the platelet glycoprotein (GP) Ib-V-IX and IIb/IIIa complexes have been described, and the PlA polymorphism of GP IIIa has been associated with coronary thrombosis. We determined the levels of beta-thromboglobulin (beta-TG) and platelet factor 4 (PF4) and the genotype distributions of PlA and a variable number tandem repeat (VNTR) polymorphism of GP 1b in subjects with acute stroke (n=609) and healthy control subjects (n=435). Levels of beta-TG were higher in patients both initially (47.4 [44.7 to 50.2] ng/mL, P<0.0001) and after 3 months (42.9 [40.3 to 45.7] ng/mL, P=0.03) compared with control subjects (39.4 [37.7 to 41.2] ng/mL). Initial levels of beta-TG were significantly higher in those who subsequently died (58.7 [52.3 to 65.8] ng/mL) compared with those still alive (42.7 [40.1 to 45.5] ng/mL, P<0.0001). In a logistic regression model, beta-TG remained an independent predictor of poststroke mortality, with an odds ratio for an increase in 10 ng/mL of 1.12 (1.03 to 1.21, P=0.006). In subjects who had never smoked, there was a significant difference in the genotype distributions of patients with atherothrombotic stroke (A1/A1=147, A1/A2=70, and A2/A2=2) compared with controls (A1/A1=165, A1/A2=47, and A2/A2=5, P=0.03). The PlA distribution of subjects with atherothrombotic stroke before the age of 50 years (A1/A1=19 and A1/A2+A2/A2=18) was also significantly different from age- and sex-matched controls (A1/A1=54 and A1/A2+A2/A2=20, P=0.02). We found no association of VNTR with stroke or poststroke mortality. These data indicate that there is a persistent state of enhanced platelet activation in subjects with acute stroke, which is associated with poststroke mortality. The increased frequency of the PlA2 allele in young subjects with atherothrombotic stroke lends further support for a role of the PlA polymorphism in acute thrombosis.

Polymorphisms of platelet glycoproteins in relation to macrovascular disease in type 2 diabetes mellitus

We set out to determine the genotype distributions of the PI(A) polymorphism of platelet glycoprotein IIIa, the HPA-3 polymorphism of platelet glycoprotein IIb, and the variable number tandem repeat (VNTR) polymorphism of platelet glycoprotein Ib in subjects with Type 2 diabetes mellitus (Type 2 DM) with (n = 125) and without (n = 90) a clinical history of macrovascular disease. In 215 white European subjects with Type 2 DM, presence of coronary artery disease was determined as a clinical history of angina, myocardial infarction (MI), coronary angioplasty or coronary artery by-pass grafting. Presence of peripheral vascular disease was defined as a clinical history of intermittent claudication with confirmatory vascular ultrasound or angiography, intermittent claudication with undetectable foot pulses and no history of arthralgia or surgery for leg ischaemia, confirmed by reference to medical case notes. Polymorphisms were detected by polymerase chain reaction amplification of DNA. There was no difference in the genotype distributions of subjects with and without macrovascular disease. In subjects with a first MI before the age of 60 years (n = 26), there was a 38% incidence of PI(A2) compared to 29% in subjects free from clinically evident macrovascular disease, but this difference did not reach statistical significance. This study does not support the hypothesis that polymorphisms of platelet glycoproteins, in particular the PI(A) polymorphism of platelet glycoprotein IIIa, play an important role in the pathogenesis of macrovascular disease in subjects with Type 2 DM.

Levels of activated FXII in survivors of myocardial infarction--association with circulating risk factors and extent of coronary artery disease

Little data is available regarding the activated form of factor XIIa (FXIIa) in survivors of myocardial infarction. 292 Caucasian patients characterised for extent of coronary atheroma by angiography and for a past history of myocardial infarction and 77 healthy controls were included in the study. To investigate the relationship between coronary artery disease, activated factor XII and other circulating factors, we studied levels of FXIIa, cholesterol, triglycerides, fasting insulin, fibrinogen, FVII:C, t-PA antigen and PAI-1 antigen. Factor XIIa levels were higher in all patients [2.5 (2.3-2.6) ng/ml] and in patients with a history of MI [2.6 (2.4-2.9) ng/ml] than in controls [1.9 (1.7-2.1) ng/ml], p < 0.0001. In patients, FXIIa levels positively correlated with FVII:C, BMI, cholesterol, insulin, PAI-1 antigen, t-PA antigen and triglycerides. In controls FXIIa levels only correlated with PAI-1 antigen and triglycerides. FXIIa levels were strongly associated with extent of coronary stenosis: 2.8 (2.6-3.1) ng/ml and 2.6 (2.3-2.9 ng/ml) in those with 2 and 3 vessels stenosed compared to 2.1 (1.9-2.3) ng/ml in those with 0 vessel stenosed (p = 0.0004). Activated FXII relates to both extent of coronary atheroma and to a past history of myocardial infarction and clusters with features of insulin resistance.

Association of the platelet Pl(A) polymorphism of glycoprotein IIb/IIIa and the fibrinogen Bbeta 448 polymorphism with myocardial infarction and extent of coronary artery disease

BACKGROUND

Platelets and fibrinogen play an integral role in the development of thrombosis and are implicated in the process of atherosclerosis. The fibrinogen Bbeta 448 polymorphism and the Pl(A) polymorphism of platelet glycoprotein IIIa are reported to be independently associated with coronary artery disease. The aim of this study was to determine the association of the fibrinogen Bbeta 448 and the platelet glycoprotein IIIa Pl(A) polymorphisms in relation to extent of coronary atheroma as characterized by angiography and a past history of myocardial infarction (MI) as assessed by World Health Organization criteria.

METHODS AND RESULTS

Caucasian patients (n=405) admitted for routine angiography for investigation of chest pain or suspected coronary artery disease were recruited. Caucasian control subjects (n=216) were recruited from local Family Health Services Authority general practice registers. Fibrinogen levels were higher (P=.04) in male patients (3.24 g/L; CI, 3.14 to 3.35) than male control subjects (3.06 g/L; CI, 2.91 to 3.21). There was a trend toward a difference (P=.06) in fibrinogen genotype distributions between female patients (1/1=93, 1/2=31, and 2/2=1) and female control subjects (1/1=67, 1/2=34, and 2/2=5). In logistic regression models the Pl(A2) genotype was associated with MI (odds ratio, 1.66; CI, 1.15 to 2.39; P=.007) and stenosis of more than one vessel (odds ratio, 1.5; CI, 1.01 to 2.26; P=.04). In men suffering an MI before the age of 47 years there was a 50% incidence of the Pl(A2) allele (P=.05), and in these subjects there was evidence of an interaction with cholesterol (P=.04).

CONCLUSIONS

We found evidence of an association of the Pl(A2) polymorphism in MI and multiple-vessel stenosis. The association with MI was strongest in young men, in whom there was also evidence of an interaction with cholesterol.

Cell populations in the bone marrow of guinea pig fetuses with intrauterine growth retardation

Bone marrow smears and blood samples were examined in guinea pig fetuses in which intrauterine growth retardation (IUGR) had been induced by uterine artery ligation and compared with those of control (well-grown) fetuses from uterine horns with intact circulation. Differential bone marrow cell counts were obtained from a count of 300 cells per smear and blood samples were assayed for hemoglobin concentration and 2,3-diphosphoglycerate (DPG). Results of blood assays showed no difference in hemoglobin concentration. DPG levels were reduced in the IUGR guinea pigs (P < .05), which could be a consequence of decreased glucose availability or represent an adaptation to reduced oxygen availability. Comparisons of bone marrow counts revealed an increase in total erythrocyte precursors (P < .05) and a decrease in total granulocytic precursors (P < .05) in IUGR fetuses. Within the erythroid lineage there was a significant increase in late (orthochromatic) erythroblasts (P < .005) in the IUGR animals compared with control animals. The granulocytic lineage of the IUGR fetuses showed a significant decrease in mature neutrophils (P < .05) and eosinophilic precursors (P < .05) compared with controls. These data suggest that the hypoxic stress of uterine artery ligation leads to an increase in medullary erythropoiesis. In concert with a previous study that showed a reduction in hepatic erythropoiesis, these data suggest a precocious shift of the anatomic site of erythropoiesis from the liver to the bone marrow under conditions of hypoxia.

von Willebrand factor and factor VIII: C in acute cerebrovascular disease. Relationship to stroke subtype and mortality

BACKGROUND

Elevated von Willebrand factor (vWF) is a risk factor in the development of acute myocardial infarction. The importance of vWF and factor VII:C in the pathogenesis of cerebrovascular disease (CVD) is poorly defined.

METHODS AND RESULTS

We studied 208 cases of stroke whose pathological type was defined by cranial computed tomography. Cerebral infarcts were grouped according to the Oxfordshire Community Stroke Project (OCSP) clinical classification. The results in patients were compared with 184 healthy reference subjects. In patients, vWF and FVIII:C levels were determined initially and after three months. Patients were followed prospectively for six months or until death. Levels of vWF and FVIII:C were elevated initially (1.86 IU/ml and 2.20 U/ml respectively) and after 3 months (1.51 IU/ml and 1.90 U/ml) compared with a healthy reference population (1.26 IU/ml and 1.49 U/ml p = 0.0001). In the initial sample, vWF was associated with age (p = 0.01). FVIII:C was related to age (p = 0.04), gender (p = 0.007 higher for females) and a history of diabetes mellitus (2.56 U/ml vs. 2.16 U/ml in non-diabetics, p = 0.008). Initial vWF levels were higher in subjects with large vessel disease (TACI/PACI) group compared with the small vessel disease (LACI) group [2.12 IU/ml, (n = 112) vs. 1.48 IU/ml (n = 59) respectively, p = 0.0001] and similarly in initial FVIII:C levels (2.43 U/ml vs. 1.87 U/ml, p = 0.0001). Analysis of six-month case fatality, vWF levels were associated with risk of death [p = 0.01, OR 1.73 (1.12, 2.66) for an increase of I U/ml], even after allowing for stroke type.

CONCLUSION

The relationship of vWF with stroke mortality has not previously been described. Although we have not demonstrated a causal role for vWF in the pathogenesis of CVD, elevated circulating levels of vWF may be associated with increased risk of death following stroke. A prospective study would be required to establish whether vWF is predictive for the development of CVD.

Vascular homeostasis, adhesion molecules, and macrovascular disease in non-insulin-dependent diabetes mellitus

Diabetes mellitus is characterized by fasting hyperglycaemia and the development of chronic vascular complications. While microvascular disease has been strongly related to glycaemic control, the major cause of mortality in diabetes is due to macrovascular disease affecting the cardiac and cerebrovascular circulations, which appear to have a more complex pathogenesis. Diabetes is associated with a 3-5-fold increase in death from myocardial infarction and similar figures pertain to stroke. The processes involved in atherothrombotic disease are complex and include variation in lipid metabolism, vascular responses, cell/cell interactions, and in the fluid and cellular phases of coagulation and fibrinolysis. The complex interactions between all of these processes are crucially altered by the metabolic milieu that characterizes diabetes mellitus, tipping the delicate balance towards atheroma formation, platelet aggregation and thrombus formation. This article will review these mechanisms and the effects of diabetes in the pathogenesis of vascular disease.

Polymorphisms of the factor VII gene and circulating FVII:C levels in relation to acute cerebrovascular disease and poststroke mortality

BACKGROUND AND PURPOSE

FVII:C has been shown to be an independent risk factor for myocardial infarction and is related to environmental and genetic factors. This study sought to investigate FVII:C levels and factor VII (FVII) gene polymorphisms in relation to stroke and disease outcome.

METHODS

To examine the association of FVII:C and the Msp I and promoter insertion polymorphisms of the FVII gene in acute stroke, 317 patients and 198 age-matched control subjects were studied.

RESULTS

FVII:C levels were significantly lower in patients at onset than 3 months later (119% versus 135%, respectively; P < .0005). Levels were significantly lower in patients at onset than in control subjects (124% [95% confidence interval, 120% to 129%] versus 141% [95% confidence interval, 135% to 148%], respectively; P < .0005) but were not significantly different at 3 months (135% [95% confidence interval, 128% to 141%] versus 141% [95% confidence interval, 135% to 148%], respectively). We found no difference in genotype distribution for either polymorphism between patients and control subjects, no difference in FVII:C level or genotype distribution between pathological types of stroke, and no relationship with poststroke mortality. Both polymorphisms were significantly associated with FVII:C levels in patients and control subjects. In a multiple regression model for patients, Msp I genotype, cholesterol, and smoking remained as independent predictors of FVII:C levels, accounting for 32% of interindividual variation.

CONCLUSIONS

These results suggest that neither FVII:C levels nor FVII gene polymorphisms are associated with cerebrovascular disease. There were no genotype-specific correlations of environmental factors with FVII:C, but there was evidence of an acute-phase or consumptive fall in FVII:C levels at the time of stroke, whereas levels increased to those similar for healthy age-matched control subjects by 3 months, when the acute phase had presumably subsided.

Plasminogen activator inhibitor-1 (PAI-1) 4G/5G promoter polymorphism and levels in subjects with cerebrovascular disease

The exact role of the fibrinolytic system in the pathogenesis of stroke remains to be established. Elevated circulating levels of plasminogen activator inhibitor-1, the principle inactivator of the fibrinolytic system, have been related to the development of myocardial infarction. There is evidence that a polymorphism in the promoter region of the PAI-1 gene is associated with circulating PAI-1 levels. We studied a common single nucleotide insertion/deletion (4G/5G) polymorphism by PCR in 558 patients with stroke, the pathological type of which was established by cranial computed tomography, and in 172 controls. 4G/5G genotype and PAI-1 activity were investigated in relation to 1) stroke type and 2) mortality occurring within four weeks, three months and six months of the stroke. No difference in genotype frequency was observed when all cases of stroke were compared with controls nor between the clinically determined subtypes of cerebral infarction. PAI-1 activity was significantly higher in patients with stroke (n = 245) both at presentation (11.6 U/ml) and after three months (11.8 U/ml), in paired samples, than in control subjects (8.8 U/ml, p < 0.0001). Thirty-seven (6.2%), 86 (14.5%) and 122 (20.5%) patients had died within one, three and six months of admission, respectively. PAI-1 activity was independently associated with all-cause mortality at one and three months after stroke (p = 0.02 and p = 0.03 respectively), but not after six months. In this population the 4G/5G promoter polymorphism is not associated with an increased risk of stroke. PAI-1 levels were elevated at the time of acute stroke which persisted after three months. PAI-1 level but not genotype was associated with early mortality following stroke.

Gender-specific associations of the fibrinogen B beta 448 polymorphism, fibrinogen levels, and acute cerebrovascular disease

Fibrinogen is an independent risk factor for the development of stroke. Factors influencing circulating levels of fibrinogen include age, smoking, gender, and genetic factors. The aim of this study was to determine the relationship between a polymorphism at position 448 of the B beta fibrinogen gene, fibrinogen levels, gender, and the risk of stroke. Fibrinogen levels were determined in 305 patients with stroke, taken within 10 days of the acute event and 3 months later, and in 197 control subjects. Initial fibrinogen levels in patients (4.49 g/L) were significantly higher than at 3 months (3.85 g/L, P < .0001), consistent with resolution of the acute-phase response. At 3 months, levels were only significantly higher than for control subjects in the male patients (3.86 g/L versus 3.31 g/L, P < .0001). Fibrinogen levels were associated with B beta 448 genotype in male patients at 3 months (1/1 = 3.62 g/L, 1/2 + 2/2 = 4.27 g/L, P = .01). There was a significant difference in the genotype distribution in female patients and control subjects (patients: 1/1 = 95, 1/2 = 34, 2/2 = 6; control subjects: 1/1 = 61, 1/2 = 50, 2/2 = 3, P = .008). These data suggest that the mechanisms linking fibrinogen and the development of cerebrovascular disease are different in males and females. In male patients, the increase in fibrinogen levels may be influenced by environmental factors, while in females there may be a functional difference in the fibrinogen molecule unrelated to fibrinogen levels.

Case management in psychiatric inpatient recapture

A 2-year reduction of $5.25 million in inpatient costs, representing a decrease of 74%, resulted from implementation of a Psychiatric Management Initiative at Munson Army Community Hospital. Case management was a major component. Management in the military Civilian Health and Medical Program of the Uniformed Services (CHAMPUS) system has major differences from the civilian sector. The military case manager functions as a "guest" in the civilian psychiatric hospitals with no authority to direct care. The practice involves trend analysis, team work, innovative treatment alternatives, and active discharge planning with follow-up. This program was successful in the recapture of CHAMPUS costs despite constraints by CHAMPUS regulations. Costs went from $3,555,285 in fiscal year 1993 down to $600,743 in fiscal year 1995.

Beta-fibrinogen gene-455 G/A polymorphism and fibrinogen levels. Risk factors for coronary artery disease in subjects with NIDDM

OBJECTIVE

To investigate the association of a G/A polymorphism at position -455 of the beta-fibrinogen gene and fibrinogen levels in the development of coronary artery disease (CAD) in subjects with NIDDM.

RESEARCH DESIGN AND METHODS

In 187 Caucasian subjects with NIDDM, presence of CAD was taken as a clinical history of angina, myocardial infarction, coronary angioplasty, or coronary artery bypass grafting, confirmed from medical case notes.

RESULTS

Fibrinogen levels were significantly higher in subjects with CAD (n = 38, 3.41 [3.12-3.73] g/l) than those without (n = 149, 2.99 [2.87-3.11] g/l, P = 0.004 [geometric mean, 95% CI]). Comparing the genotype frequencies by chi 2 testing, there was a significant difference between subjects with CAD (GG = 0.84, GA + AA = 0.16) and those without (GG = 0.64, GA + AA = 0.36, P = 0.02). In a logistic regression model, including age, BMI, cholesterol, sex, smoking, triglycerides, and plasminogen activator inhibitor antigen as covariates, genotype and fibrinogen levels were significantly associated with CAD. The odds ratio for having CAD in individuals homozygous for the G allele compared with those possessing the A allele was 1.77 (1.08-2.90), P = 0.03; and for an increase of 1 g/l in fibrinogen levels was 1.60 (1.00-2.60), P = 0.05.

CONCLUSIONS

These data suggest a relationship between the -455 G/A beta-fibrinogen gene polymorphism and the development of CAD in subjects with NIDDM. This relationship was not associated with variations in fibrinogen levels, suggesting that this polymorphism may be in linkage with a polymorphism within the coding region of the beta-fibrinogen gene, which results in an alteration in the stability of the fibrin clot.

Effect of fetal growth restriction on system A amino acid transporter activity in the maternal facing plasma membrane of rat syncytiotrophoblast

To determine whether reduced maternofetal transfer of neutral amino acids in growth-restricted fetal rats is due to decreased system A transporter activity, we measured Na(+)-dependent MeAIB uptake by membrane vesicles from placentas of fetuses growth-restricted due to uterine artery ligation and control placentas (sham ligation). Na(+)-dependent uptake of methylamino-isobutyric acid (MeAIB) was linear over 15-60 s in vesicles from both ligated and sham-ligated sides of the uterus. Na(+)-dependent uptake of MeAIB at 30 s did not differ in paired measurements on vesicles from ligated and sham-ligated horns, 0.063 +/- 0.004 versus 0.056 +/- 0.005 nmol/mg of vesicle protein. The kinetics of Na(+)-dependent MeAIB uptake were similar in paired measurements on vesicles from ligated and sham-ligated horns, with overall K(m) = 4.4 +/- 0.5 mM and Vmax = 0.93 +/- 0.08 nmol/mg vesicle protein per 30 s. Uptake of tracer was inhibited 85-95% by known substrates for the system A amino acid transporter (alanine > or = serine > MeAIB > glycine = proline). We conclude that the system A transporter is present in the maternal facing plasma membrane of rat syncytiotrophoblast, but that the activity of this system, per mg of vesicle protein, is unaffected in fetal growth restriction induced by a decrease in maternal placental blood flow in late pregnancy.

The influence of Helicobacter pylori status on circulating levels of the coagulation factors fibrinogen, von Willebrand factor, factor VII, and factor VIII

BACKGROUND

Helicobacter pylori (H. pylori) infection has been associated with an increased risk of developing ischemic heart disease (IHD). It has been suggested that a persisting low-grade acute phase response results from the chronic inflammation caused by H. pylori infection, which may give rise to increased circulating levels of certain coagulation factors.

MATERIALS AND METHODS

One hundred three (53 male) nonconsecutive, randomly selected white subjects with symptoms of dyspepsia were recruited for study from an outpatient endoscopy clinic at Leeds General Infirmary. The presence of H. pylori was determined by histological and microbiological investigation, a rapid urease test, and a 13carbon urea breath test (13C-UBT). Fibrinogen was measured by the Clauss method, factor VIII:C (FVIII:C) and factor VII:C (FVII:C) were measured by clotting rate assays, and the von Willebrand factor (vWF) was determined by an enzyme-linked immunosorbent assay.

RESULTS

No difference was found in levels of coagulation factors according to H. pylori status. Multiple regression models were used to account for the effect of covariates and H. pylori status on levels of FVII:C, FVIII:C, vWF, and fibrinogen, and again H. pylori status was not a significant determinant of levels of any of these coagulation factors. No difference occurred in full blood count, platelet count, white cell count, or plasma viscosity in individuals who were H. pylori-positive compared with those who were negative.

CONCLUSIONS

H. pylori infection is not associated with increased circulating levels of fibrinogen, FVII:C, vWF.Ag, or FVIII:C or hemorrheology in this patient group.

Angiotensin-converting enzyme insertion/deletion polymorphism and cerebrovascular disease

BACKGROUND AND PURPOSE

There is evidence that an allelic variation in the angiotensin-converting enzyme (ACE) gene may confer an increased risk of vascular disease. The roles of the ACE insertion/deletion polymorphism and circulating ACE levels are unknown in cerebrovascular disease.

METHODS

We studied an insertion/deletion polymorphism within intron 16 of the ACE gene by polymerase chain reaction and plasma ACE activity in 467 cases of stroke, the pathological type of which was established by cranial CT, and 231 control subjects. ACE genotype and activity were related to stroke type and mortality at 4 weeks and 3 months.

RESULTS

No difference in genotype frequency was observed between all subjects with stroke and control subjects or between control subjects and subjects with cerebral infarction or cerebral hemorrhage. Plasma ACE activity was significantly lower in stroke patients at presentation (64.1 IU/L) than in control subjects (79.6 IU/L; P<.0001). Twenty-one patients (4.5%) with cerebral infarction died within 4 weeks and 56 patients (12%) within 3 months. These patients had significantly lower plasma ACE activity than patients who survived. There was some evidence that risk of death within 4 weeks increased with the number of D alleles (P=.02). Among survivors, plasma ACE activity showed a mean increase of 6.9 IU/L (95% confidence interval, 3.0 to 10.8) between levels at presentation and at 3 months (73.6 IU/L), the latter being similar to ACE activity in control subjects.

CONCLUSIONS

Low ACE activity at sroke presentation and possession of the D allele may be associated with increased risk of early death from acute cerebral infarction.