Arg506 to Gln mutation in the factor V gene causes poor fibrinolytic response in children after venous occlusion

To determine to what extent the Arg506 to Gln mutation in the factor V gene influences the fibrinolytic response after 20 min venous occlusion (VO) we investigated a population of APC resistant children (n = 60) and a group of age-matched healthy controls (n = 25). After 20 min VO, symptomatic (n = 30) carriers of the common factor V mutation showed significantly reduced t-PA activities compared with asymptomatic (n = 30) carriers (p <0.0001) and healthy controls (p <0.0001). In contrast, PAI 1 activity was significantly (p <0.0001) higher before and after VO in children with the factor V mutation compared with healthy children. No difference was found between symptomatic and asymptomatic probands. A significantly lower PAI 1 antigen decrease along with a lower t-PA antigen release was found in the APC resistant children compared with the controls. No significant difference was seen between individuals with and without previous vascular insults. As the lack of t-PA activity after VO in symptomatic carriers is the most conspicuous result, we suggest that the factor V gene mutation itself might induce the fibrinolytic impairment by increasing the thrombin levels and thus increasing the recently described thrombin-activable fibrinolysis inhibitor (TAFI).

The Saccharomyces cerevisiae peroxisomal 2,4-dienoyl-CoA reductase is encoded by the oleate-inducible gene SPS19

beta-Oxidation is compartmentalized in mammals into both mitochondria and peroxisomes. Fatty acids with double bonds at even-numbered positions require for their degradation the auxiliary enzyme 2,4-dienoyl-CoA reductase, and at least three isoforms, two mitochondrial and one peroxisomal, exist in the rat. The Saccharomyces cerevisiae Sps19p is 34% similar to the human and rat mitochondrial reductases, and an SPS19 deleted strain was unable to utilize petroselineate (cis-C18:1(6)) as the sole carbon source, but remained viable on oleate (cis-C18:1(9)). Sps19p was purified to homogeneity from oleate-induced cells and the homodimeric enzyme (native molecular weight 69,000) converted 2,4-hexadienoyl-CoA into 3-hexenoyl-CoA in an NADPH-dependent manner and therefore contained 2,4-dienoyl-CoA reductase activity. Antibodies raised against Sps19p decorated the peroxisomal matrix of oleate-induced cells. SPS19 shares with the sporulation-specific SPS18 a common promoter region that contains an oleate response element. This element unidirectionally regulates transcription of the reductase and is sufficient for oleate induction of a promoterless CYC1-lacZ reporter gene. SPS19 is dispensable for growth and sporulation on solid acetate and oleate media, but is essential for these processes to occur on petroselineate.

Safety and efficacy of urapidil and sodium nitroprusside in the treatment of hypertensive emergencies

OBJECTIVE

To assess the safety and efficacy of urapidil compared to sodium nitroprusside in the treatment of hypertensive emergencies.

DESIGN

Randomized, prospective clinical study.

SETTING

Emergency department in a 2000-bed inner city hospital.

PATIENTS

Eighty-one patients with hypertensive emergencies defined as elevation of systolic blood pressure above 200 mmHg and/or diastolic blood pressure above 110 mmHg plus evidence of end-organ damage were included in the study protocol. The efficacy of therapy was defined as 1) blood pressure reduction below 180/95 mmHg within 90 min and 2) no re-elevation of blood pressure during a 4-h follow-up period in primary responders. The safety of both drugs was defined as the number of minor and major side effects during treatment.

INTERVENTIONS

Patients received either sodium nitroprusside (n = 35; continuous intravenous administration with a starting dose of 0.5 microgram/kg per min; increase in increments of 0.5 microgram/kg per min every 15 min until response to treatment or a maximum of 3 micrograms/kg per min) or urapidil (n = 46; intravenous bolus; starting dose: 12.5 mg; repetitive administration of 12.5 mg every 15 min until response or a maximum dose of 75 mg).

MEASUREMENTS AND RESULTS

Blood pressure was measured every 2.5 min by using a non-invasive oscillometric blood pressure measurement unit. Response to treatment within 90 min was observed in 75 (93%) patients (urapidil: n = 41 [89%]; nitroprusside: n = 34 [97%]; p = 0.18). During the follow-up period 8/34 (24%) patients in the nitroprusside group and 1/41 (2%) patients in the urapidil group exhibited blood pressure re-elevation. Major side effects were observed in seven patients receiving nitroprusside and two patients in the urapidil group (p = 0.04).

CONCLUSION

Urapidil is equally effective, compared to sodium nitroprusside, in the treatment of hypertensive emergencies. Due to a smaller number of adverse events, urapidil is a reasonable alternative to nitroprusside in the treatment of hypertensive emergencies.

Statistical evaluation of epiluminescence microscopy criteria in the differential diagnosis of malignant melanoma and pigmented basal cell carcinoma

Pigmented basal cell carcinoma (PBCC) is a tumour with distinct clinical features which occasionally may be difficult to differentiate from malignant melanoma (MM). The purpose of this study was to re-examine the epiluminescence microscopy (ELM) criteria for PBCC and to determine their statistical significance in the differential diagnosis of MM. Fifty histologically verified pigmented skin lesions (25 PBCCs and 25 MMs) were investigated using ELM for the presence of ELM criteria; their significance was determined by calculating the odds ratios. We found that individual ELM criteria have different weights of significance in the differential diagnosis of PBCC (leaf-like distribution of diffuse pigmentation, gradual thinning at the periphery and telangiectasia) and MM (pigment network, black and grey pigmentation, radial streaming, pseudopods, brown globules and black dots). Selected patterns of ELM criteria adjusted to the distinct types of pigmented skin lesions are characteristic features for preoperative diagnosis. The prevalence of distinct ELM criteria in PBCC and MM is of critical value in differentiating between the two types of lesions.

A simple and reliable reverse-phase high-performance liquid chromatographic procedure for determination of paclitaxel (taxol) in human serum

A simple, fast, and reliable isocratic (mobile phase: acetonitrile/methanol/water [48/11/41], reverse-phase (C18 column) high-performance liquid chromatography method for the determination of paclitaxel concentration in human serum is presented. The procedure uses a new and convenient one-step sample-purification procedure that requires only 400 microliters of sample and uses N-heptylbenzamide as an internal standard. Paclitaxel is detected by UV absorbance measurement at 227 nm. The method has a broad linear range (0.01 to 10 mg/l, or 0.012 to 11.7 mumol/l; r > 0.999), and the detection limit is 0.01 mg/l (0.012 mumol/l). The deviation from target value is < or = 1.5%, and coefficients of variation are < or = 13.8% within runs and < or = 15.3% between runs. Recovery paclitaxel is > or = 92.6%. No interferences were observed from endogenous compounds or from more than 30 drugs that may be administered with paclitaxel. Docetaxel, which is not concurrently administered, coeluted with paclitaxel. Compared with previously published high-performance liquid chromatography procedures for the determination of paclitaxel, the particular advantage of the method presented here is its simple and rapid single-step sample-purification procedure, which makes a high recovery of paclitaxel from serum samples possible and results in a pure extract, avoiding interferences from endogenous compounds. The method is suitable for pharmacological studies and routine analysis.

Quantification of vascularity in nodular melanoma and Spitz's nevus

Spitz's nevi are acquired benign melanocytic skin tumors. Usually they are differentiated from nodular melanoma by clinical and histopathological criteria. Since Spitz's nevi are one of the most common simulators of nodular melanomas their bizarre histopathology may cause diagnostic confusion and make it difficult to differentiate these two melanocytic tumors. One of the histologic features shared by Spitz's nevus and nodular melanoma is prominent vascularity. The ability of malignant melanoma to induce angiogenesis is well established whereas benign melanocytic tumors do not have a prominent overall vascularity. The purpose of this study was to find out whether the degree of vascularity of nodular melanomas differs significantly from that of benign Spitz's nevi. In this study the number of microvessels and the vessel area were determined in 23 Spitz's nevi and 16 nodular melanomas. The number of microvessels and the vessel area were determined on Ulex Europaeus agglutinin I-stained sections by computer-assisted image analysis. Two methods of measurement were used, namely systematic and selective sampling. Measurement of the whole tumor specimen (systematic sampling) revealed a vessel count of 10.83/field (SD +/-5.97) for Spitz's nevi whereas nodular melanomas exhibited a significantly lower (p=0.04) vessel count of 6.44/field (SD +/-3.85). This difference was even more pronounced when the vessel area (Spitz's nevi: 17.85x10-4mm2, SD +/-10.32; nodular melanomas: 7.88x10-4mm2, SD +/-5.23) was investigated (p < 0.001). The difference in vessel area and vessel count was insignificant for areas exhibiting the greatest vascularity (selective sampling). Measurement of vessel count and vessel area lead us to conclude that Spitz's nevi have a significantly higher vascularity than do nodular melanomas. Our results thus indicate that angiogenesis in these pigmented lesions is not correlated with malignancy.

Molecular biology of the hexokinase isoenzyme pattern that distinguishes pathogenic Entamoeba histolytica from nonpathogenic Entamoeba dispar

The electrophoretic patterns of hexokinase and phosphoglucomutase have been widely used to distinguish Entamoeba histolytica from Entamoeba dispar isolates. Although E. histolytica and E. dispar, previously called pathogenic and nonpathogenic Entamoeba histolytica, differ clearly in sequences of many homologous genes, a conversion between the two has been reported by several laboratories, in each case showing the conversion of hexokinase (ATP, D-hexose 6-phosphotransferase, EC 2.7.1.1) isoenzyme patterns. An apparent mobility shift of this enzyme may either be due to posttranslational modification or processing, or to the appearance of a new isoform encoded by a second gene. In this study we observed that the four observed bands in the isoenzyme patterns of pathogenic and nonpathogenic forms of Entamoeba were correlated with four different cDNAs, and that the four recombinant hexokinases produced in Escherichia coli comigrated with their natural counterparts. Polymerase chain reaction (PCR) experiments did not reveal hidden genes which might be responsible for conversion phenomena. These results strongly support the redefinition of pathogenic and nonpathogenic Entamoeba histolytica as two closely related species Entamoeba histolytica and Entamoeba dispar.

Double-blind trial of botulinum A toxin for the treatment of focal hyperhidrosis of the palms

We performed a randomized double-blind study within-group comparison in 11 patients to study the effect of subcutaneous injections of botulinum A toxin in focal hyperhidrosis of the palms. A total dose of 120 mU (mouse units) of botulinum A toxin (Dysport) was injected into six different sites on one palm, whereas the other was injected with sterile saline. Objective quantification of sweat production was performed using digitized ninhydrin-stained sheets. Three weeks after treatment, the mean reduction of sweat production in the botulinum A toxin-treated palms was 26% (P < 0.001), after 8 weeks 26% (P = 0.002) and after 13 weeks 31% (P < 0.001). Subjective assessment of sweat production by the patients using a visual analogue scale showed a 38% improvement in the botulinum A toxin-treated palms at 3 weeks (P = 0.002), 40% at 8 weeks (P = 0.002) and 38% at 13 weeks (P = 0.002). Neither the objective measurement nor the subjective rating showed a statistically significant reduction of sweating in the placebo-treated palms. Three patients reported reversible minor weakness of powerful handgrip after injection at the toxin-treated site, lasting between 2 and 5 weeks.

Blood glucose concentration after cardiopulmonary resuscitation influences functional neurological recovery in human cardiac arrest survivors

Experimental data suggest that postischemic blood glucose concentration plays an important role in modulating both ischemic cerebral infarction and selective neuronal necrosis. This study investigated the association between functional neurological recovery and blood glucose concentrations in human cardiac arrest survivors. A group of 145 nondiabetic patients were evaluated after witnessed ventricular fibrillation cardiac arrest. Data regarding cardiac arrest were collected according to an internationally accepted protocol immediately after arrival. Blood glucose was measured on admission and 6, 12, and 24 h thereafter. To control for duration of cardiac arrest and cardiogenic shock, both known to influence outcome as well as blood glucose, levels, Spearman rank partial correlation was used. In this multivariate analysis, a high admission blood glucose level tended to be associated with poor neurological outcome (rs = -0.16, n = 142, p = 0.06). The association between high median blood glucose levels over 24 h and poor neurological outcome was strong and statistically significant (rs = -0.2, n = 145, p = 0.015). High blood glucose concentrations occurring over the first 24 h after cardiac arrest have deleterious effects on functional neurological recovery. Whether cardiac arrest survivors might benefit from reduction of blood glucose levels needs further investigation.

Impact of the renin-angiotensin-aldosterone system on blood pressure response to intravenous enalaprilat in patients with hypertensive crises

The purpose of the study was to evalute the impact of the renin-angiotensin-aldosterone (RAA) system on blood pressure (BP) response in patients with hypertensive emergencies and urgencies treated with intravenous enalaprilat. Thirty-five patients with a systolic BP (SBP) >210 mm Hg and/or diastolic BP (DBP) >110 mm Hg received 5 mg enalaprilat intravenously. The extent of systolic and DBP reduction was correlated with pretreatment concentrations of angiotensin II (ANGII) (SBP: r = -0.47; P = 0.006; DBP: r = -0.55; P = 0.001) and plasma renin activity (PRA) (SBP: r = -0.49; P = 0.003; DBP: r = 0.48; P = 0.007). Non-responders to enalaprilat exhibited significant lower pretreatment levels of PRA, angiotensin-converting enzyme (ACE) and ANG II compared to responders (PRA: 5.5 +/- 3.7 vs 1.1 +/- 2.2 ng/ml/h, P < 0.001; ACE: 12.8 +/- 3.5 vs 8.2 +/- 4.8 U/l, P = 0.003; ANG 11:8.7 +/- 6.2 vs 5.0 +/- 3.8 pg/ml, P = 0.04). In patients with severe hypotension following application of enalaprilat ANG II concentrations were significantly higher compared to patients with mean arterial BP reduction <25% (12.3 +/- 6.7 vs 5.6 +/- 4.0 pg/ml,P = 0.013). These data indicate that PRA and ANG II are the major determinants for BP response to enalaprilat. This relation between BP response and RAA system activity have important clinical implications for the treatment of patients with severe hypertension. Primary therapeutic failure indicates that the RAA system contributes very little to the hypertensive status of the patient. Thus, repetitive application on an ACE inhibitor in primary responders is clinically unhelpful and may result in an unnecessary delay of an effective BP reduction. In contrast, high ANG II concentrations are associated with a considerable risk for severe hypotension after enolanalaprilat application. Therefore, the status of the RAA system determines the efficacy as well as the safety of ACE inhibitor treatment in patients with severe hypertension.

Embryonic lethality and impairment of haematopoiesis in mice heterozygous for an AML1-ETO fusion gene

Acute myeloid leukaemia (AML) is a major haematopoietic malignancy characterized by the proliferation of a malignant clone of myeloid progenitor cells. A reciprocal translocation, t(8;21)(q22;q22), observed in the leukaemic cells of approximately 40% of patients with the M2 subtype of AML disrupts both the AML1 (CBFA2) gene on chromosome 21 and the ETO (MTG8) gene on chromosome 8 (refs 3-5). A chimaeric protein is synthesized from one of the derivative chromosomes that contains the N terminus of the AML1 transcription factor, including its DNA-binding domain, fused to most of ETO, a protein of unknown function. We generated mice that mimic human t(8;21) with a "knock-in' strategy. Mice heterozygous for an AML1-ETO allele (AML1-ETO/+) die in midgestation from haemorrhaging in the central nervous system and exhibit a severe block in fetal liver haematopoiesis. This phenotype is very similar to that resulting from homozygous disruption of the AML1 (Cbfa2) or Cbfb genes, indicating that AML1-ETO blocks normal AML1 function. However, yolk sac cells from AML1-ETO/+ mice differentiated into macrophages in haematopoietic colony forming unit (CFU) assays, unlike Cbfa2-/- or Cbfb-/-cells, which form no colonies in vitro. This indicates that AML1-ETO may have other functions besides blocking wild-type AML1, a property that may be important in leukaemogenesis.

Epiluminescence microscopy of small pigmented skin lesions: short-term formal training improves the diagnostic performance of dermatologists

BACKGROUND

Epiluminescence microscopy (ELM) makes subsurface structures of the skin accessible for in vivo examination and provides additional criteria for the clinical diagnosis of pigmented skin lesions (PSLs). We demonstrated that ELM increases diagnostic sensitivity in dermatologists formally trained in the use of this technique but decreases diagnostic ability in dermatologists not formally trained in its application.

OBJECTIVE

Our purpose was to determine the effects of short formal ELM training on the diagnostic performance of 11 previously untrained dermatologists.

METHODS

One hundred image-pairs of randomly selected histologically proven PSLs, photographed with (ELM) and without oil immersion (surface microscopy), were presented by slide projection to the testees. To evaluate the effects on diagnostic performance before and after short-term training, we used the receiver-operator characteristics technique.

RESULTS

Without training the use of ELM did not enhance diagnostic accuracy, but rather decreased it in 8 of 11 testees. In contrast, after 9 hours of formal training in ELM the diagnostic performance of the testees was significantly enhanced with an average gain of 8.4%.

CONCLUSION

Our data confirm that formal training is required for the useful application of the ELM technique.

Obsessive-compulsive disorder with and without tics in an epidemiological sample of adolescents

OBJECTIVE

This study was undertaken to discriminate subtypes of obsessive-compulsive disorder in adolescents.

METHOD

Forty individuals with obsessive-compulsive spectrum disorders were ascertained from an epidemiological sample of 861 adolescents. Interviews were conducted by child psychiatrists using semistructured diagnostic interviews, including a clinician-rated Yale-Brown Obsessive Compulsive Scale. Discriminant analysis was performed to compare the scores on the Yale-Brown scale of groups with and without comorbid tics and to compare boys and girls.

RESULTS

Adolescents with tics were more prone to aggressive and sexual images and obsessions than were adolescents without tics; these differences could not be wholly attributed to sex differences.

CONCLUSIONS

The subtypes among unreferred adolescents are similar to those of adult patients with obsessive-compulsive disorder with and without Gilles de la Tourette syndrome. Subtypes evident in adulthood may be established relatively early in the natural course of obsessive-compulsive disorder.

Systemic activation of coagulation and fibrinolysis during varicose vein stripping

BACKGROUND

Elevation of activation markers of blood coagulation (thrombin-antithrombin complex [TAT], prothrombin fragment 1 + 2 [F1 + 2], D-Dimer] has not only been found in clinically overt thrombosis but also reflects a prethrombotic state.

OBJECTIVE

The purpose of our study was to evaluate whether varicose vein stripping, an operative procedure with an extremely low risk of postoperative thromboembolism, induces a prethrombotic state by activation of the hemostatic system.

METHODS

In a prospective, observational study we compared the baseline and postoperative values of TAT, F1 + 2, and D-Dimers in 15 patients undergoing varicose vein stripping and in 11 control patients undergoing surgical procedures associated with only minor soft tissue trauma.

RESULTS

A highly significant postoperative elevation of TAT (P < 0.001), F1 + 2 (P = 0.006), and D-Dimer (P < 0.001) was observed in the varicose vein stripping group. No significant postoperative change of the respective parameters was detected in the control group.

CONCLUSION

We therefore conclude that varicose vein stripping induces a significant hemostatic system activation although postoperative thrombotic events are rare.

Assessment of myocardial injury by serum tumour necrosis factor alpha measurements in acute myocardial infarction

Clinical and experimental data have shown that after acute myocardial infarction there is a significant release of tumour necrosis factor alpha. Therefore, an attempt was made to correlate changes in serum tumour necrosis factor alpha concentrations with indices of infarct extent in patients with acute myocardial infarction. In 50 patients with acute myocardial infarction, blood samples for evaluation of tumour necrosis factor alpha and alpha-hydroxybutyrate-dehydrogenase were collected every 6 h until 120 h after admission. Infarct extent was estimated by clinical parameters such as the occurrence of heart failure and rhythm disturbances, by enzymatic methods such as cumulative release of alpha-hydroxybutyrate-dehydrogenase and imaging techniques, by late resting single photon emission tomography--201 thallium scintigraphy--using an extent score and by echocardiography using a wall motion index. The maximum change in serum tumour necrosis factor alpha after infarction (delta TNF) was calculated by subtracting tumour necrosis factor alpha concentration on admission from peak tumour necrosis factor alpha concentration. The average peak tumour necrosis factor alpha level was observed 84 h after admission (median: 12 pg.ml-1). Between the 72nd and the 96th h no significant changes in tumour necrosis factor alpha values were observed. Analysis of the data showed that larger delta (TNF) values were found to be associated significantly with signs of heart failure (P = 0.003), the presence of rhythm disturbances (P = 0.001), increased enzymatic infarct extent indicated by cumulative release of alpha-hydroxybutyrate-dehydrogenase (r = 0.74; P < 0.001), large myocardial perfusion defects measured with 201 thallium scintigraphy (r = 0.80; P < 0.001), and a considerable number of left ventricular wall motion abnormalities (r = 0.57; P < 0.001). In conclusion, delta (TNF) is a reliable method of assessing damage severity in the myocardium after acute myocardial infarction. As only two blood samples are necessary within 84 h, the method may be one of the more convenient for the assessment of infarct size in clinical practice.

The CBFbeta subunit is essential for CBFalpha2 (AML1) function in vivo

The CBFbeta subunit is the non-DNA-binding subunit of the heterodimeric core-binding factor (CBF). CBFbeta associates with DNA-binding CBFalpha subunits and increases their affinity for DNA. Genes encoding the CBFbeta subunit (CBFB) and one of the CBFalpha subunits (CBFA2, otherwise known as AML1) are the most frequent targets of chromosomal translocations in acute leukemias in humans. We and others previously demonstrated that homozygous disruption of the mouse Cbfa2 (AML1) gene results in embryonic lethality at midgestation due to hemorrhaging in the central nervous system and blocks fetal liver hematopoiesis. Here we demonstrate that homozygous mutation of the Cbfb gene results in the same phenotype. Our results demonstrate that the CBFbeta subunit is required for CBFalpha2 function in vivo.

Creatine kinase-mb fraction and cardiac troponin T to diagnose acute myocardial infarction after cardiopulmonary resuscitation

OBJECTIVES

This study sought to evaluate the diagnostic value of the biochemical markers creatine kinase (CK), creatine kinase-MB fraction (CK-MB) and cardiac troponin T (cTNT) to diagnose acute myocardial infarction (AMI) after cardiopulmonary resuscitation (CPR).

BACKGROUND

Elevations of CK and CK-MB after CPR are a frequent finding and might be associated with ischemic myocardial injury, as well as physical trauma to the chest.

METHODS

Patients who had cardiac arrest and primary successful resuscitation were included in the study. The diagnosis of AMI was confirmed or ruled out by means of typical electrocardiographic findings, thallium-201 myocardial scintigraphy or autopsy, if death occurred during the hospital period, in 39 primary survivors of sudden cardiac death. In 24 patients (62%) the diagnosis of AMI was established. Serum cTNT, CK and CK-MB were measured, and the CK-MB/CK ratio was calculated on admission and after 12 h.

RESULTS

On admission all markers of myocardial injury proved to be weak methods for the diagnosis of AMI. After 12 h cTNT as well as CK-MB exhibited a similar diagnostic performance; CK and the CK-MB/CK ratio proved to be worthless. Sensitivity and specificity for a cTNT cutoff value of 0.6 ng/ml, 12 h after cardiac arrest, were 96% and 80%, respectively. For a CK-MB cutoff value of 26 U/liter, sensitivity was 96% and specificity was 73%.

CONCLUSIONS

Cardiac TNT and CK-MB are valuable tools in detecting AMI as the cause of sudden cardiac death. However, there is a considerable lack of sensitivity and specificity. Cardiac injury is probably caused not only by AMI, but also by myocardial damage related to CPR efforts.