Microalbuminuria and pulse pressure in hypertensive and atherosclerotic men

To identify the biological covariates of microalbuminuria (albuminuria >/=15 microg/min) in nondiabetic subjects, brachial blood pressure, echocardiographic left ventricular mass, and other cardiovascular and metabolic parameters were evaluated in 211 untreated males (38 normal controls, 109 uncomplicated stage 1 to 3 essential hypertensives, and 64 patients with clinically stable atherosclerotic peripheral vascular disease either with [n=44] or without [n=20] essential hypertension) with normal cardiac and renal function. Compared with normoalbuminuric subjects, microalbuminuric subjects (n=67) were characterized by higher systolic blood pressure, comparable diastolic blood pressure, and, therefore, wider pulse pressure. Greater prevalence of hypertension, peripheral vascular disease, left ventricular hypertrophy, and reduced HDL cholesterol values further distinguished microalbuminuric from normoalbuminuric subjects in univariate comparisons. The risk of microalbuminuria increased by ascending pulse pressure quintiles in age-corrected logistic regression models, in which pulse pressure was more predictive than systolic pressure and was independent of mean pressure. When microalbuminuric status was regressed against a series of dichotomous (vascular and active smoker status) and continuous (age, pulse and mean pressure, left ventricular mass index, and HDL and LDL cholesterol) variables, only pulse pressure, left ventricular mass index, and smoking status were independent predictors. The association of increased albuminuria with wider pulse pressure, a correlate of the pulsatile hemodynamic load and conduit vessel stiffness as well as an important cardiovascular risk factor, may explain why microalbuminuria predicts cardiovascular events in nondiabetic subjects. The independence from concomitant vascular disease also suggests that wider pulse pressure, rather than representing a simple marker for atherosclerotic disease, influences albuminuria directly.

Myocardial "hybrid" revascularisation with minimally invasive direct coronary artery bypass grafting combined with coronary angioplasty: preliminary results of a multicentre study

OBJECTIVE

To expand the benefits of the minimally invasive direct coronary artery bypass (MIDCAB) concept to patients with multivessel disease, a hybrid procedure combining surgical revascularisation of the left anterior descending artery with interventional procedures for additional coronary lesions has recently been introduced. Preliminary results in patients undergoing this hybrid procedure are presented.

DESIGN AND PATIENTS

Since December 1996, 35 patients (29 male, 6 female, mean (SD) age 56.7 (17) years) underwent a hybrid revascularisation performed as a primary MIDCAB procedure for grafting of the left anterior descending artery with the left internal mammary artery, followed by staged angioplasty and stenting of additional coronary lesions.

RESULTS

After MIDCAB grafting the postoperative course was uneventful in all patients. Coronary reangiography after a median of seven days revealed patent and functioning left internal mammary artery grafts in all patients. Applying subsequent percutaneous transluminal coronary angioplasty and occasional stenting (n = 14), a total of 47 lesions were treated successfully. Procedure related complications did not occur. All patients remained free from angina and no stress ECG changes were recorded.

CONCLUSIONS

The preliminary results of this hybrid approach to myocardial revascularisation suggest that this is a safe and effective procedure for complete revascularisation in selected patients with multivessel disease. Elderly and reoperative patients with significant comorbidity may benefit especially from such hybrid procedures by avoiding cardiopulmonary bypass and mid sternotomy.

Incessant nonreentrant atrioventricular nodal tachycardia due to multiple nodal pathways treated by radiofrequency ablation of the slow pathways

In patients with dual AV nodal physiology, simultaneous anterograde fast and slow pathway conduction resulting in an unusual form of nonreentrant AV nodal tachycardia has been observed. We describe the case of a young patient with an incessant form of complex supraventricular tachycardia who underwent electrophysiologic evaluation, which showed simultaneous conduction via multiple AV nodal pathways that caused a unique form of incessant nonreentrant AV nodal tachycardia. Radiofrequency ablation of the spatially closed intermediate and slow pathways effectively treated the tachycardia. The electrophysiologic determinants of simultaneous conduction through the multiple nodal pathways and the apparently different behavior of the fast pathway before and after ablation are discussed.

Two murine and human homologs of mab-21, a cell fate determination gene involved in Caenorhabditis elegans neural development

We report the cloning and genetic characterization of one human and two murine homologs of the mab-21 cell fate specification gene. mab-21 participates in the formation of sensory organs in the male nematode tail, and is essential for other developmental functions elsewhere in the Caenorhabditis elegans embryo. The expanding mab-21 gene family, which is strikingly conserved in evolution, includes two putative Drosophila members. The two mammalian genes, encoding 41 kDa nuclear basic proteins, are expressed in partially overlapping territories in the embryonic brain, eye and limbs, as well as in neural crest derivatives. Recent genetic data implicating mab-21 as a downstream target of TGF-beta signaling, together with the distribution of mab-21 transcripts in the mouse embryo, propose these novel genes as relevant factors in various aspects of vertebrate neural development.

Endothelin-1 release from atherosclerotic plaque after percutaneous transluminal coronary angioplasty in stable angina pectoris and single-vessel coronary artery disease

To assess the effects of percutaneous transluminal coronary angioplasty on endothelin-1 (ET-1) release, we assessed ET-1 concentrations at different sites of the coronary circulation in patients submitted to elective procedures. ET-1 levels immediately downstream from the plaque and ET-1 aortocoronary gradient increased significantly after the procedure, which was related to mechanical wall stress in patients only receiving balloons, but not in those undergoing stent percutaneous transluminal coronary angioplasty. No changes were found in the coronary sinus; these results suggest ET-1 release from the plaque rather than an ischemia/reperfusion-related production from the distal myocardium.

A homeobox gene, vax2, controls the patterning of the eye dorsoventral axis

We have identified a transcription factor specifically expressed in the developing vertebrate eye. We named this gene vax2 because of the high degree of sequence similarity to the recently described vax1. Both in the human and mouse genomes, vax2 is localized in the vicinity of the emx1 gene. This mapping assignment, together with the previously reported colocalization of Vax1 and Emx2 in mouse, indicates that the vax and the emx genes may be organized in clusters. vax2 has a remarkable expression domain confined to the ventral portion of the prospective neural retina in mouse, human, and Xenopus. The overexpression of either the frog Xvax2 or the human VAX2 in Xenopus embryos leads to an aberrant eye phenotype and, in particular, determines a ventralizing effect on the developing eye. The expression domain of the transcription factor Xpax2, normally confined to the ventral developing retina, extends to the dorsal region of the retina after overexpression of vax2. On the other hand, the expression of Xvent2, a molecular marker of the dorsal retina, is strongly reduced. Furthermore, vax2 overexpression induces a striking expansion of the optic stalk, a structure deriving from the ventralmost region of the eye vesicle. Altogether, these data indicate that vax2 plays a crucial role in eye development and, in particular, in the specification of the ventral optic vesicle.

Microalbuminuria and transcapillary albumin leakage in essential hypertension

Microalbuminuria (an increased urinary albumin excretion that is not detectable by the usual dipstick methods for macroproteinuria) predicts cardiovascular events in essential hypertensive patients. A possible reason for this behavior is that albumin leaks through exaggeratedly permeant glomeruli exposed to the damaging impact of subclinical atherogenesis. To evaluate this possibility, the transcapillary escape rate of albumin (TER(alb), the 1-hour decline rate of intravenous (125)I-albumin), a parameter that estimates the integrity of systemic capillary permeability, albuminuria, blood pressure, echocardiographic left ventricular mass, lipids, and body mass index were measured in 73 uncomplicated, glucose-tolerant men with essential hypertension and normal renal function; 53 were normoalbuminuric, and 20 were microalbuminuric. Twenty-one normotensive age-matched male subjects were the controls. TER(alb) was higher in hypertensives, a behavior explained in part by a positive correlation with blood pressure values, although body mass index, lipids, and left ventricular mass showed no association. Transcapillary albumin leakage values did not differ between normoalbuminuric and microalbuminuric patients and were unrelated to albuminuria. Blood pressure, particularly systolic, and cardiac mass were higher in microalbuminuric patients in whom albuminuria correlated with both cardiovascular variables and indicated the influence of the hemodynamic load on urinary albumin levels. Thus, TER(alb), a parameter influenced by the permeability surface area product for macromolecules and the filtration power across the vascular wall, is altered in essential hypertensives. However, this abnormality is dissociated from the amount of albuminuria, which is contrary to the hypothesis that a higher albumin excretion reflects a greater degree of systemic microvascular damage in essential hypertension.

[The management of syncope in the hospital: the OESIL Study (Osservatorio Epidemiologico della Sincope nel Lazio)]

BACKGROUND

While syncope is generally considered a frequent finding in clinical practice, no clear epidemiological evidence is available about the relevance of such an event in the general population of Italy.

METHODS

The OESIL Study was designed and undertaken in 15 hospitals of the Italian region of Latium in order to assess the percentage of emergency-room visits and admissions due to syncope, as well as to analyze the in-hospital diagnostic work-up performed for this condition.

RESULTS

During a two-month observation period, 781 (372 males and 409 females, mean age 55.2 (22.8 years) consecutive patients came to the emergency rooms of the 15 hospitals included in the investigation due to a syncope spell (0.9% of emergency room visits); 450/781 patients (57.6%) were subsequently hospitalized (1.3% of all admissions): 48.0% of the admissions were admitted to a general medical ward, 29.3% to an observation ward, 13.3% to a cardiology section, 1.6% to a neurology section and 7.8% to other clinical sections (neurosurgery, general surgery). The mean duration of in-hospital stay was 6.9 (5.8 days; range 1-40 days). During the hospitalization period, 93.1% of patients underwent an ECG, 51.0% an EEG, 44.3% a CT scan of the central nervous system, 40.2% an echocardiogram and 19.5% a tilt-test. The syncope spell was considered to have a cardiovascular origin in 33.8% of the cases and a non-cardiovascular in 11.6% of the cases, while the origin was unknown in 54.4% of the cases.

CONCLUSIONS

Collected data support the idea that syncope represents a frequent event in the general population and is responsible for a significant percentage of emergency-room visits and hospital admissions. However, the performance of conventional diagnostic work-ups is far from being satisfactory.

Changing heat and moisture exchangers every 48 hours does not increase the incidence of nosocomial pneumonia

This prospective study was conducted to evaluate the risk of nosocomial pneumonia when changing heat and moisture exchangers every 48 hours in 1996 instead of every 24 hours in 1995 for patients needing continuous mechanical ventilation. Medical and surgical patients in the two periods did not differ in terms of demographic characteristics and markers of acute or underlying illnesses. The incidence density of nosocomial pneumonia was not different in the two groups. Extended heat and moisture exchanger use reduces circuit manipulation and cost.

The structure in solution of the b domain of protein disulfide isomerase

Protein disulfide isomerase (PDI) is a multifunctional protein of the endoplasmic reticulum, which catalyzes the formation, breakage and rearrangement of disulfide bonds during protein folding. It consists of four domains designated a, b, b and a. Both a and a domains contains an active site with the sequence motif -Cys-Gly-His-Cys-involved directly in thiol-disulfide exchange reactions. As expected these domains have structures very similar to the ubiquitous redox protein thioredoxin. A low-resolution NMR structure of the b domain revealed that this domain adopts a fold similar to the PDI a domain and thioredoxin [Kemmink, J., Darby, N.J., Dijkstra, K., Nilges, M. and Creighton, T.E. (1997) Curr. Biol. 7, 239-245]. A refined ensemble of solution structures based on the input of 1865 structural restraints shows that the structure of PDI b is well defined throughout the complete protein except for about 10 residues at the C-terminus of the sequence. 15N relaxation data show that these residues are disordered and not part of this structural domain. Therefore the domain boundaries of PDI can now be fixed with reasonable precision. Structural comparison of the PDI b domain with thioredoxin and PDI a reveals several features important for thiol-disulfide exchange activity.

Dissociation between albuminuria and insulinaemia in hypertensive and atherosclerotic men

To better understand the links between circulating insulin and albuminuria in essential hypertension, the plasma insulin response t alpha a 75 gram glucose load and albuminuria were evaluated in 53 glucose-tolerant essential hypertensives and 12 controls. To allow any direct pressure-independent albuminuric effect of insulin to emerge more clearly, those same parameters were also evaluated in 20 glucose-tolerant normotensive patients with stable atherosclerotic peripheral vascular disease, a condition in which hyperinsulinaemia could be anticipated on the basis of previous reports. In response to glucose ingestion, hyperinsulinaemia was evident in both hypertensive and normotensive atherosclerotic patients, while, on average, urine albumin was elevated only in the former. When plasma insulin, systolic and diastolic blood pressure (BP) (by 24-h ambulatory BP monitoring), plasma glucose, triglycerides and body mass index were entered into a multiple regression analysis, only systolic BP appeared to exert an independent effect on urine albumin. Post-glucose load plasma insulin did not differ between hypertensive patients with (n = 14) and without (n = 39) microalbuminuria (albuminuria > 20 micrograms/min). In further analyses, insulin and systolic BP values were divided in quartiles: albuminuria did not differ across insulin quartiles, while it was significantly higher in the top (n = 21) vs the bottom (n = 21) systolic BP quartile. Thus, hyperinsulinaemia and microalbuminuria were unrelated variables in these hypertensive and atherosclerotic patients. Blood pressure, particularly systolic, emerged as a primary predictor of urinary albumin excretion, although the importance of this parameter needs to be proved prospectively.

Identification and characterization of CDS2, a mammalian homolog of the Drosophila CDP-diacylglycerol synthase gene

The general strategies of phototransduction in vertebrates and invertebrates share many similarities, but differ significantly in their underlying molecular machinery. The CDS gene encodes the CDP-diacylglycerol synthase (CDS) enzyme and is required for phototransduction in Drosophila. Using a bioinformatic approach, we have identified two novel transcripts (CDS1 and CDS2) highly homologous to the Drosophila CDS gene. We isolated and sequenced the CDS2 full-length cDNA and mapped the two genes to human chromosomes 20p13 (CDS2) and 4q21.1 (CDS1). Sequence analysis revealed that both genes are highly homologous to the Drosophila protein (64.4 and 58. 6% identity at the protein level between CDS and CDS2 and between CDS and CDS1, respectively). The mouse homologs for both genes were isolated and used in RNA in situ hybridization studies on adult and embryonic mouse tissue sections. These studies showed that Cds2 is highly expressed in the differentiating neuroblasts of the neural retina and in the central nervous system during embryonic development, while it was not detected in adult retina. Cds1, on the other hand, shows a high level of expression in the photoreceptor layer of adult retina, which strongly suggests a role for Cds1 in phototransduction. Knowledge of the expression pattern of these genes in mammals may shed light on the evolution of vision mechanisms and help in the evaluation of candidate genes for human retinopathies.

Fibrinogen and mortality in chronic critical limb ischaemia

OBJECTIVE

Plasma fibrinogen predicts cardiovascular events in patients with stable peripheral arterial occlusive disease, but its predictive value in patients with chronic critical limb ischaemia, a condition associated with a high risk of death, is unknown.

DESIGN

A prospective cohort study.

SETTING

Determination of fibrinogen and other potential predictors during clinic-based work-up of patients admitted for diagnostic and therapeutic evaluation.

SUBJECTS

A total of 108 patients (72 +/- 10 years, 78 males) with atherosclerotic occlusive disease and critical limb ischaemia (pain at rest and/or trophic lesions) followed up for a median period of 1.6 years). (range: 8 days-5.5 years; 218 patient-years).

MAIN OUTCOME MEASURES

Total mortality.

RESULTS

Forty-five deaths (71% cardiovascular) occurred during the follow-up. Baseline fibrinogen was higher in those who died in the early follow-up period (first 6 months), as were white cell count and serum creatinine, while haematocrit was lower. Plasma fibrinogen values correlated positively with white cell count, and negatively with haematocrit; other cardiovascular prognostic factors did not differ. Only plasma fibrinogen predicted survival independently in multivariate age-corrected Cox regression analysis. Relative risk of death doubled for each standard deviation above the mean and increased with each tertile increase in fibrinogen.

CONCLUSIONS

Fibrinogen predicted death in these elderly arteriopaths with critical limb ischaemia, particularly those who died in the first months following critical ischaemia. Inflammatory stimuli secondary to severely defective tissue oxygenation and possibly sepsis and necrosis, might have stimulated fibrinogen, an acute-phase reactant, thereby compromising organ perfusion through increased blood viscosity and/or promoting thrombosis.

EYA4, a novel vertebrate gene related to Drosophila eyes absent

We have isolated a family of four vertebrate genes homologous to eyes absent (eya), a key regulator of ocular development in Drosophila. Here we present the detailed characterization of the EYA4 gene in human and mouse. EYA4 encodes a 640 amino acid protein containing a highly conserved C-terminal domain of 271 amino acids which in Drosophila eya is known to mediate developmentally important protein-protein interactions. Human EYA4 maps to 6q23 and mouse Eya4 maps to the predicted homology region near the centromere of chromosome 10. In the developing mouse embryo, Eya4 is expressed primarily in the craniofacial mesenchyme, the dermamyotome and the limb. On the basis of map position and expression pattern, EYA4 is a candidate for oculo-dento-digital (ODD) syndrome, but no EYA4 mutations were found in a panel of ODD patients.

Mab21, the mouse homolog of a C. elegans cell-fate specification gene, participates in cerebellar, midbrain and eye development

A multitude of regulatory genes are involved in phylogenetically conserved developmental cascades required for the patterning, cell-type specification, and differentiation of specific central nervous system (CNS) structures. Here, we describe the distribution of a mouse transcript encoding a homolog of the C. elegans mab-21 gene. In the nematode tail, mab-21 is required for the short-range patterning and cell-fate determination events mediated by egl-5 and mab-18, two homeobox genes homologous to Abd-B and Pax6, respectively. In mouse midgestation embryogenesis, Mab21 is expressed at its highest levels in the rhombencephalon, cerebellum, midbrain, and prospective neural retina. Our data and the genetic interactions previously documented in the nematode suggest that Mab21 may represent a novel, important regulator of mammalian cerebellum and eye development.

Structural alterations of alpha-crystallin during its chaperone action

The small heat-shock protein, alpha-crystallin, has chaperone ability whereby it stabilises proteins under stress conditions. In this study, alterations in the structure of alpha-crystallin during its interaction with a variety of substrate proteins (insulin, alpha-lactalbumin, ovotransferrin and serum albumin) under stress conditions have been examined using visible absorption, 31P-NMR and 1H-NMR and fluorescence spectroscopy. The fluorescence and 31P-NMR data imply that during the chaperone action of alpha-crystallin under reducing conditions, there is a slight increase in hydrophilicity of its N-terminal region and an alteration in flexibility of its C-terminal region, but overall, alpha-crystallin does not undergo a gross structural change. The fluorescence data suggest that substrate proteins interact with alpha-crystallin in a molten globule or intermediately folded state. The same conclusion is made from 1H-NMR spectroscopic monitoring of the interaction of alpha-crystallin with substrate proteins, e.g. the insulin B chain. The stoichiometry of interaction between alpha-crystallin and the various substrate proteins reveals that steric factors are important in determining the efficiency of interaction between the two proteins, i.e. on a molar subunit basis, alpha-crystallin is a more efficient chaperone protein with smaller substrate proteins. Comparison is also made between the high-molecular-mass (HMM) complexes formed between alpha-crystallin and ovotransferrin when reduced and heat stressed. Under heating conditions, fluorescence spectroscopy indicates that the HMM complex has a greater exposure of hydrophobicity to solution than that formed by reduction. Furthermore, in interacting with heated ovotransferrin, the C-terminal extension of the alphaB-crystallin subunit preferentially loses its flexibility suggesting that it is involved in stabilising bound ovotransferrin. By contrast, this extension is only partially reduced in flexibility in the HMM complex formed after reduction of ovotransferrin. The functional role of the C-terminal extensions in the chaperone action and the overall quaternary structure of alpha-crystallin is discussed.

Sulfhydryl redox state affects susceptibility to ischemia and sarcoplasmic reticulum Ca2+ release in rat heart. Implications for ischemic preconditioning

We investigated the effect of sulfhydryl and disulfide reagents on ischemic preconditioning and on sarcoplasmic reticulum Ca2+ release. Isolated working rat hearts were subjected to ischemic preconditioning (three 3-minute periods of global ischemia) or to control aerobic perfusion, which was followed by 30 minutes of global ischemia and 120 minutes of retrograde reperfusion. Necrosis was evaluated on the basis of lactate dehydrogenase release and triphenyltetrazolium chloride staining. In parallel experiments, sarcoplasmic reticulum Ca2+ release and [3H]-ryanodine binding were determined before the sustained ischemia. Ischemic preconditioning was associated with protection versus ischemic injury, decreased Ca2+ release and reduced [3H]-ryanodine binding. The disulfide reducing agent dithiothreitol (1 mmol/L) removed the protection provided by ischemic preconditioning, if added to the perfusion buffer either before or after the preconditioning procedure. In preconditioned hearts, dithiothreitol increased sarcoplasmic reticulum Ca2+ release and ryanodine binding, whereas in control hearts it had no effect on either tissue injury or sarcoplasmic reticulum function. Perfusion of control hearts with the sulfhydryl blocking agents 4,4'-dithiodipyridine (25 micromol/L) and N-ethylmaleimide (16 micromol/L) increased the resistance to ischemia and reduced sarcoplasmic reticulum Ca2+ release and [3H]-ryanodine binding. These effects were not additive with those induced by preconditioning. Sulfhydryl and disulfide reagents produced similar effects on Ca2+ release and [3H]-ryanodine binding if added in vitro to preparations obtained from control and preconditioned hearts. We conclude that ischemic preconditioning is associated with the oxidation of sulfhydryl groups involved in the modulation of sarcoplasmic reticulum Ca2+ release.

Coronary collateral circulation behaviour and myocardial viability in chronic total occlusion treated with coronary angioplasty

AIMS

We explored the role of microcirculation integrity following the chronic occlusion of an infarct-related artery to assess the behaviour of collateral circulation during and after reperfusion by coronary angioplasty

METHODS AND RESULTS

Eighteen patients with a proximally occluded left anterior descending artery and firm evidence of intercoronary collateral circulation were studied with selective coronary angiography and selective intracoronary myocardial contrast echocardiography, before coronary angioplasty, and at 5 and 15 min and 12 h later. Myocardial enhancement during myocardial contrast echocardiography was evaluated with a semiquantitative score (0-3), which was correlated to basal and 6 months' regional left ventricular wall motion results. 16/18 procedures were successfully performed; four patients with an inadequate acoustic window were excluded. Restenosis was evident at the 6 months' follow-up in two patients. Basal myocardial contrast echocardiography indicated that 81/192 segments from the left anterior descending coronary artery and 90/192 from the right coronary artery were perfused; no perfusion was observed in 21 segments either before or after coronary angioplasty. After coronary angioplasty, the angiographic intercoronary collateral circulation immediately disappeared, and myocardial contrast echocardiography revealed that there was a progressive reduction of segments perfused by the right coronary artery and an increase in segments perfused by the left anterior descending coronary artery. Regional left ventricular wall motion analysis demonstrated that there was abnormal motion in 51/192 segments. There was no improvement in segments with score 0 and abnormal motion after 6 months (100% sensitivity), but 16/17 segments with score 3 did show an improvement (98% specificity). The predictive value of intermediate scores (1-2) in detecting long-term improvement, was only 43%.

CONCLUSION

These data show that the adaptive mechanism observed in the behaviour of epicardial and microvascular circulation after reperfusion of a chronic occluded infarct-related artery can vary. In addition, this study clearly shows that microvascular integrity detected by myocardial contrast echocardiography can provide myocardial viability.

A competitive enzyme-linked immunosorbent assay for measuring the levels of serum antibody to Haemophilus influenzae type b

A competitive ELISA method is described for the measurement of total antibodies to the capsular polysaccharide of Haemophilus influenzae type b (HibCPS) in human sera. The competitive method showed an excellent correlation to the radioantigen binding assay (RABA, or Farr assay) and improved correlation of sera with low titers with respect to the more conventional noncompetitive method. Overestimation of samples in the low concentration range was no longer observed with the competitive ELISA method. The free HibCPS competition allowed us to eliminate the day-to-day background variation typical of some sera; thus, only values representing the true anti-HibCPS response were determined. The use of precoated microplates, which could be stored up to 8 months, greatly improved the speed of the procedure. An overall correlation coefficient of 0. 9660 was found when 407 serum samples with a wide variety of anti-HibCPS antibody levels were tested with the competitive ELISA and RABA. The regression line was very close to the ideal line, with a slope of 1.0045 and an intercept of -0.1996. A subset of 96 serum samples representative of all pre- and postimmunization samples was used to compare the competitive ELISA with a previously described ELISA method. The competitive method performed in two laboratories in different countries showed a better correlation with the RABA. The correlation factors were 0.9770 and 0.9816, respectively, while a factor of 0.9547 was found with the previously described noncompetitive procedure, which was better for this method than previously reported (r = 0.917). Therefore, the competitive ELISA is proposed for the assay of anti-HibCPS titers in sera from vaccinated subjects.

Identification and characterization of a novel serine-threonine kinase gene from the Xp22 region

Eukaryotic protein kinases are part of a large and expanding family of proteins. Through our transcriptional mapping effort in the Xp22 region, we have isolated and sequenced the full-length transcript of STK9, a novel cDNA highly homologous to serine-threonine kinases. A number of human genetic disorders have been mapped to the region where STK9 has been localized including Nance-Horan (NH) syndrome, oral-facial-digital syndrome type 1 (OFD1), and a novel locus for nonsyndromic sensorineural deafness (DFN6). To evaluate the possible involvement of STK9 in any of the above-mentioned disorders, a 2416-bp full-length cDNA was assembled. The entire genomic structure of the gene, which is composed of 20 coding exons, was determined. Northern analysis revealed a transcript larger than 9.5 kb in several tissues including brain, lung, and kidney. The mouse homologue (Stk9) was identified and mapped in the mouse in the region syntenic to human Xp. This location is compatible with the location of the Xcat mutant, which shows congenital cataracts very similar to those observed in NH patients. Sequence homologies, expression pattern, and mapping information in both human and mouse make STK9 a candidate gene for the above-mentioned disorders.

Transvascular and urinary leakage of albumin in atherosclerotic and hypertensive men

Increased urine albumin is associated with atherosclerotic disease and predicts cardiovascular morbidity and mortality in nondiabetic populations. This finding is frequently postulated to reflect the impact of atherosclerotic damage on glomerular and systemic capillary permeability, an interesting but as yet untested hypothesis. The transcapillary escape rate of albumin (TERalb, the 1-hour decline rate of intravenous 125I-albumin, a measure of capillary macromolecular permeability), albuminuria, lipid levels, echocardiographic wall thickness, and insulin responses to oral glucose were measured in 30 untreated dipstick-negative lean men and clinically stable atherosclerotic peripheral vascular disease; tolerance to oral glucose was a requirement for inclusion in the study. Because hypertension per se might influence TERalb, the sample included either normotensive (n=18, 118+/-6/72+/-7 mm Hg) or hypertensive (n=12, 141+/-7/84+/-6 mmHg by 24-hour blood pressure monitoring) arteriopathic patients; 11 normal age- and gender-matched subjects (121+/-7/76+/-5 mmHg) were used as control subjects. TERalb was higher in patients (10.7+/-3.2 versus 7.4+/-1.7%/h, P<0.013), a difference that persisted after postload glucose, insulin, and lipid levels were accounted for by covariance analysis; atherosclerosis and hypertension together did not further impair vascular permeation to albumin. In contrast with TERalb, albuminuria was elevated only in the hypertensive subgroup; the 2 variables showed no relationship, even when the data were analyzed separately in normotensive and hypertensive subgroups. Urine albumin correlated positively with 24-hour blood pressure and wall thickness. Thus, systemic capillary permeability is altered in nondiabetic atherosclerotic patients independently from blood pressure levels, but this abnormality is not reflected by proportionate changes in albuminuria.

Characterization of Cxorf5 (71-7A), a novel human cDNA mapping to Xp22 and encoding a protein containing coiled-coil alpha-helical domains

The human X chromosome is known to contain several disease genes yet to be cloned. In the course of a project aimed at the construction of a transcription map of the Xp22 region, we fully characterized a novel cDNA, Cxorf5 (HGMW-approved symbol, alias 71-7A), previously mapped to this region but for which no sequence information was available. We isolated and sequenced the full-length transcript, which encodes a predicted protein of unknown function containing a large number of coiled-coild domains, typically presented in a variety of different molecules, from fibrous proteins to transcription factors. We showed that the Cxorf5 cDNA is ubiquitously expressed, undergoes alternative splicing, and escapes X inactivation. Furthermore, we precisely mapped two additional Cxorf5-related loci on the Y chromosome and on chromosome 5. By virtue of its mapping assignment to the Xp22 region, Cxorf5 represents a candidate gene for at least four human diseases, namely spondyloepiphiseal dysplasia late, oral-facial-digital syndrome type 1, craniofrontonasal syndrome, and a nonsyndromic sensorineural deafness.

[Deep venous thrombosis: epidemiologic, diagnostic and therapeutic aspects]

Deep vein thrombosis (DVT) has a high social and economic cost disease being its prevalence in the general population elevated and producing possibly fatal (pulmonary embolism) or disabling (post-thrombotic syndrome) complications. Thus, it appears of great importance to know the epidemiological and clinical characteristics of DVT in order to perform the best diagnosis, therapy and prophylaxis. The study population is composed by 146 patients (84 males and 62 females, mean age 60.9 +/- 15.3 years, range 19.92 years), arrived in our Vascular Echography Laboratory with the clinical suspect of DVT confirmed by means of echo color Doppler. The most frequent clinical signs were skin hyperthermia in 118 patients (80.8%) and edema in 116 patients (79.5%), while the most common symptom was pain, 89 patients (61.0%). Eleven patients (7.5%) were asymptomatic. The echo criteria utilized were direct thrombus visualization, vessel diameter higher than the contralateral, reduced or absent vessel wall ability to be compressed, reduced or absent color Doppler venous flow, lack or reduction of respiratory flow modulation, visualization of collateral circulation. DVT was located in 131 patients (89.7%) in inferior limbs (proximal in 122 patients, isolated distal in 9 patients), in 14 patients (9.6%) in superior limbs and in 3 patients (2.1%) in the internal jugular vein. In 130 patients a risk factor or a predisposing condition was identified: secondary DVT; in 16 patients the DVT was considered idiopathic. The most frequent risk factors were: previous surgery 28.1%, immobilization 19.9% trauma 17.1%, tumors 9.6%. A hypercoagulation was detected in 4 patients: antithrombin III deficit in 2, post-splenectomy thrombocytosis in 1 and antiphospholipid antibodies syndrome in the last one. The Pisa territory epidemiologic data showed a male 0.51 and female 0.38/1000 subject/year DVT incidence, with significantly higher values in older than 45-54 males and 55-64 females. One hundred and thirty one patients were treated with 5-11 day heparin infusion and thereafter with warfarin at least for 6 months, 1 year or indefinitely depending on thromboembolic risk. Six patients with distal DVT and 9 patients with hemorrhagic risk were treated with subcutaneous calcic or low weight heparin. In 1 patient with a mobile thrombus judged as at very high risk of embolization, a caval filter was positioned. Anticoagulant therapy complications were: 2 minor bleedings, 1 alopecia, 1 thrombocytopenia. Two patients died for neoplastic complications. Fifty-seven patients completed a 6-month follow-up and were submitted to a control each study that evidenced: total recanalization in 15 (26.3%), partial recanalization in 25 (43.9%) and no recanalization in 17 patients (29.8%). In 6 patients there was a DVT relapse and in 9 pulmonary embolization: almost all these patients were in the partial recanalization group.

Epithelial V-like antigen (EVA), a novel member of the immunoglobulin superfamily, expressed in embryonic epithelia with a potential role as homotypic adhesion molecule in thymus histogenesis

Thymus development depends on a complex series of interactions between thymocytes and the stromal component of the organ. To identify regulated genes during this codependent developmental relationship, we have applied an RNA fingerprinting technique to the analysis of thymus expansion and maturation induced in recombinase-deficient mice injected with anti-CD3 antibodies. This approach led us to the identification of a gene encoding a new member of the immunoglobulin superfamily, named epithelial V-like antigen (EVA), which is expressed in thymus epithelium and strongly downregulated by thymocyte developmental progression. This gene is expressed in the thymus and in several epithelial structures early in embryogenesis. EVA is highly homologous to the myelin protein zero and, in thymus-derived epithelial cell lines, is poorly soluble in nonionic detergents, strongly suggesting an association to the cytoskeleton. Its capacity to mediate cell adhesion through a homophilic interaction and its selective regulation by T cell maturation might imply the participation of EVA in the earliest phases of thymus organogenesis.

Aneuploidy and diploidy rates in sperm of five men after three-colour hybridization: indication of X chromosome-associated autosome 2 aneuploidy

The frequencies of aneuploidy and diploidy for chromosomes 2, X and Y in sperm nuclei of five nonsmoking normal donors were assessed by three-colour fluorescence in situ hybridization. We detected neither significant interindividual variability nor age effect (age range of the study group: 26-38 yr) on the mean frequencies of aneuploid and diploid sperm. Nullisomic sperm were observed more frequently than disomic sperm. In addition, sex chromosomal meiotic nondisjunction occurred at a higher rate than autosomal nondisjunction, and disomic sperm for the sex chromosomes were formed mainly by errors in the second meiotic division. Our data indicate that diploidy occurs at a very low frequency in comparison with aneuploidy. Furthermore, the overall proportion of X-bearing sperm nuclei aneuploid for chromosome 2 is significantly higher than that of Y-bearing sperm (0.14% vs. 0.05%, respectively; p < 0.001). This finding adds further evidence that autosomal aneuploidy can be preferentially associated with the presence of one of the two gonosomes.