Usefulness of glycoprotein IIb/IIIa inhibitors in unstable angina due to small vessel disease

We describe the role of abciximab in unstable angina due to small vessel disease in a 58-year-old patient who was submitted to percutaneous transluminal coronary angioplasty and stenting of an occluded venous graft.

Prenatal diagnosis of ATR-X syndrome in a fetus with a new G>T splicing mutation in the XNP/ATR-X gene

The molecular cause of the alpha-thalassemia/mental retardation syndrome (ATR-X) resides in mutations affecting the XNP/ATR-X gene. Recently molecular defects in the gene have been found in singular cases of a discrete number of X-linked mental retardation (XLMR). ATR-X-affected males are characterised by severe mental retardation, distinct facial dysmorphisms and genital abnormalities, besides a wide spectrum of pathological features and an extremely limited biological fitness. Given that molecular investigation of XNP/ATR-X mutations is made onerous by the length of the gene transcript, we carried out a prenatal diagnosis in a fetus at risk for ATR-X syndrome by initially determining the XNP/ATR-X gene haplotype before considering gene sequencing. Disease-associated haplotype analysis was performed selecting five genic (CA)n repeats that showed high heterozygosity (Het>0.7) in the general population. The fetus segregated an identical allelic pattern to that of the affected child of the family under investigation who shows features suggestive of the ATR-X syndrome. Subsequent mutational analysis of the gene revealed a novel IVS3+1G>T splicing mutation confirming the diagnosis.

Incremental prognostic value of technetium-99m-tetrofosmin exercise myocardial perfusion imaging for predicting outcomes in patients with suspected or known coronary artery disease

Technetium-99m (Tc-99m)-tetrofosmin is a radio isotope that has been shown to be an accurate alternative to thallium-201 for detecting coronary artery disease. However, its prognostic value is less well determined. To this end, 459 consecutive patients (mean age 58 +/- 10 years) with suspected or known coronary artery disease underwent exercise single-photon emission tomography Tc-99m-tetrofosmin scintigraphy. Follow-up, defined as the time from scanning until a soft event (revascularization procedures), a hard event (myocardial infarction and cardiac death), or patient response, lasted up to 78 months (median 38). An ischemic scintigraphic perfusion score, which takes into account both the extent and severity of reversible perfusion defects, was calculated to estimate the severity of perfusion abnormalities. Patients with normal scans were at low risk of events (yearly hard event rate 0.5% and soft event rate 0.9%). The rate of outcomes increased significantly with abnormal scans (yearly hard event rate 4.9% and soft event rate 10.3%). Statistical analysis using the Kaplan-Meyer survival curves showed a significant difference in event-free survival between patients with normal and abnormal scans. With use of Cox proportional-hazards analysis, after adjusting for prescan information, nuclear data provided incremental prognostic value for hard events (clinical and exercise data vs nuclear data; chi-square = 15.5 vs 33.4, p <0.001). Exercise single-photon emission tomographic scintigraphy using Tc-99m-tetrofosmin provides significant independent information on the subsequent risk of hard and soft events. The annual event rate for hard and soft events is <1% for patients with a normal scan. Furthermore, this tracer yields incremental prognostic information in addition to that provided by clinical and exercise data for hard events.

Different geographic origins of Hb Constant Spring [alpha(2) codon 142 TAA-->CAA]

BACKGROUND AND OBJECTIVES

The occurrence of Hb CS is usually limited to the geographic area which includes Southern China and South East Asia. In 1968 Hb CS was also found to occur in the Mediterranean area where it was originally described as Hb Athens. We investigated the independent origin of these termination codon mutations of the alpha 2-globin gene by determining the alpha-cluster haplotype and comparing the hematologic data from Hb CS-Hb H patients and their family members.

DESIGN AND METHODS

We studied one Hb CS-Hb H patient of Greek origin and a Sicilian family in which one individual was affected by Hb CS-Hb H. The haplotype of the Hb CS allele was determined and compared to the haplotype of an Hb CS-Hb H individual of Chinese origin.

RESULTS

The haplotype found for the Greek and Sicilian Hb CS was the same but differed significantly from the Asiatic Hb CS mutation.

INTERPRETATION AND CONCLUSIONS

The Hb CS mutation found in both Mediterranean patients arose independently in the Mediterranean area. The difference in clinical manifestation of the Hb CS-Hb H disease in both patients is less common but consistent with similar variation in the clinical expression of analogous Hb Icaria-Hb H disease patients.

New mutations in XNP/ATR-X gene: a further contribution to genotype/phenotype relationship in ATR/X syndrome. Mutations in brief no. 176. Online

The molecular causes of ATR-X syndrome reside in mutations involving the XNP/ATR-X gene, which maps in the Xq13.3 region. Mutational analysis of this gene in two unrelated affected patients allowed us to identify two new molecular defects in two distinct regions of the gene. The first is a A-->G splice mutation in the acceptor site of the intron 11 that removes most of the 3' part of the protein, including the helicase domains and the glutamic acid stretch. Three cryptic acceptor splice sites are activated by this point mutation with consequent production of three types of abnormal mRNA: two with intronic insertions and a smaller one, approximately 10% of the total transcript, which is shorter than normal mRNA by one amino acid residue (E). Since the physiopathological characteristics of the patient carrying the splice mutation do not exhibit severe urogential abnormalities despite the lack of the -COOH end of the protein, a residual function of this third transcript is to be suspected. The second encountered nucleotide change (G-->T) leads to an R246L amino acid substitution in the putative zinc finger DNA-binding domain in the -NH2 terminal part of the protein.

Evidence that a dodecamer duplication in the gene HOPA in Xq13 is not associated with mental retardation

A recent study suggested that a dodecamer duplication in exon 42 of the HOPA gene in Xq13 may be a significant factor in the etiology of X-linked mental retardation. In an effort to investigate this possibility, we determined the incidence of the dodecamer duplication in cohorts of non-fragile X males with mental retardation from three countries, cohorts of fragile X males from two countries, 43 probands from families with X-linked mental retardation and control cohorts from three countries. The duplication was found in 3.6-4.0% of male patients from two non-fragile X groups (Italy and South Carolina), in 1.2% from another non-fragile X group (South Africa), but in no male patients from families with X-linked mental retardation (South Carolina). The dodecamer duplication was also found in several white males with fragile X syndrome from France (5%) and South Africa (22.2%). Additionally, the duplication was found in 1.5% of South Carolinian newborn males, 2.5% South Carolinian male college students, 5% Italian male controls and 4.5% of the white South African controls. None of the black South African non-fragile X individuals with mental retardation, the fragile X or the control samples tested carried the duplication, suggesting that the duplication is rare in the black South African population. The incidence of the duplication was not significantly different between any of the groups in the study. Therefore, results of our studies in four different populations do not corroborate the findings of the previous study, and indicate that the HOPA dodecamer duplication does not convey an increased susceptibility to mental retardation.

Genetic variations in human fetal globin gene microsatellites and their functional relevance

Short tandem repeats are abundantly present within the genome. They are commonly used as polymorphic markers but their potential functional role is poorly documented. Several of these microsatellites have been described within the beta-globin locus and some could be involved in controlling gene expression. Our purpose was to investigate the extent and significance of the (TG)n(CG)m dinucleotide repeat polymorphisms in the two gamma-globin gene IVS2s. Two groups of subjects were studied: a group of 63 beta-thalassaemic patients presenting either with a severe Cooley's anaemia (n=50) or with thalassaemia intermedia (TI, n=13), and a control group of 60 unrelated healthy individuals. A high heterogeneity of the polymorphic repeats was demonstrated, extending the range of the published alleles from 13 to 22 and allowing a first attempt at making a phenotype/genotype correlation. One specific allele, (TG)13 in the Agamma-gene, was highly enriched in the TI patients (46.1% vs 2.9% of the Cooley's anaemia cases, P < 0.0002, and 23.3% in the normal controls, P < 0.008) and preferentially observed in TI patients with a high haemoglobin F (Hb F). Transient transfection assays in K562 cells, with the growth hormone gene as a reporter, showed a positive regulatory action mediated by a (TG)13-containing 243 nt IVS2 fragment. Finally, a first set of mobility shift experiments with erythroid (K562 and MEL) and nonerythroid (HeLa) cell lines showed binding of erythroid component(s) in this DNA region and the binding pattern was modified upon induction of MEL cells by DMSO. Thus, our in vivo and in vitro data raise the question of a possible contribution of the gamma-gene IVS2s polymorphic microsatellites to the variable Hb F synthesis in the major haemoglobinopathies: a well known, puzzling and still unanswered question.

Evaluation of a mutation screening strategy for sporadic cases of ATR-X syndrome

We report on the evaluation of a strategy for screening for XNP/ATR-X mutations in males with mental retardation and associated dysmorphology. Because nearly half of the mutations in this gene reported to date fall into a short 300 bp region of the transcript, we decided to focus in this region and to extend the mutation analysis to cases with a negative family history. This study includes 21 mentally retarded male patients selected because they had severe mental retardation and a typical facial appearance. The presence of haemoglobin H or urogenital abnormalities was not considered critical for inclusion in this study. We have identified six mutations which represents a mutation detection rate of 28%. This figure is high enough for us to propose this strategy as a valid first level of screening in a selected subset of males with mental retardation. This approach is simple, does not require RNA preparation, does not involve time consuming mutation detection methods, and can thus be applied to a large number of patients at a low cost in any given laboratory.

Network analyses of Y-chromosomal types in Europe, northern Africa, and western Asia reveal specific patterns of geographic distribution

In a study of 908 males from Europe, northern Africa, and western Asia, the variation of four Y-linked dinucleotide microsatellites was analyzed within three "frames" that are defined by mutations that are nonrecurrent, or nearly so. The rapid generation and extinction of new dinucleotide length variants causes the haplotypes within each lineage to diverge from one another. We constructed networks of "adjacent" haplotypes within each frame, by assuming changes of a single dinucleotide unit. Two small and six large networks were obtained, the latter including 94.9% of the sampled Y chromosomes. We show that the phenetic relationships among haplotypes, represented as a network, result largely from common descent and subsequent molecular radiation. The grouping of haplotypes of the same network thus fits an evolutionarily relevant criterion. Notably, this method allows the total diversity within a sample to be partitioned. Networks can be considered optimal markers for population studies, because reliable frequency estimates can be obtained in small samples. We present synthetic maps describing the incidence of different Y-chromosomal lineages in the extant human populations of the surveyed areas. Dinucleotide diversity also was used to infer time intervals for the coalescence of each network.

Molecular basis of alpha-thalassemia in Sicily

To evaluate the allelic frequency and genetic diversity of alpha-thalassemia defects in Sicily, both epidemiological and patient-oriented studies were carried out. For the epidemiological study, phenotypic data were collected on more than 1000 Sicilian individuals. Among them, 427 were explored at the molecular level for nine alpha-thalassemic variants known to be common in the Mediterranean region. Our data reveal an allele frequency of 4.1% for alpha(+)-thalassemia matching that of beta-thalassemia in this region. The presence of alpha0-thalassemia (--MEDI and --CAL) was observed only in the group of referred patients. Newly acquired nucleotide sequence data on the deletional breakpoint of --CAL allowed us to design a simple PCR-based procedure for exploring this allele. The data also provide additional information concerning the genetic mechanisms involved in such large deletions.

Celiac disease in Down's syndrome with HLA serological and molecular studies

The association between Down's syndrome (DS) and celiac disease (CD) has been confirmed by several authors. The sensitivity and specificity of antigliadin antibodies (AGAs), the clinical features of subjects with DS and CD (DS-CD+), the incidence of CD, and the results of serological and molecular class I and II HLA typing were determined in a sample of 57 Sicilian subjects with DS. Six (10.5%) and 17 subjects (29.8%) showed high levels of IgA AGAs and IgG AGAs, respectively. AGAs sensitivity and specificity were lower than in the population without DS. Ten people with DS were submitted to jejunal biopsy, and seven (12.2%) showed CD according to ESPGAN criteria. All seven patients were put on gluten-free diet, followed by rapid disappearance of symptoms. Class I and II HLA serological and molecular typing was carried out in seven DS-CD + subjects, 22 people with DS without CD (DS-CD-), five subjects with CD without DS, and 20 controls. Between DS-CD + and DS-CD- subjects, no statistically significant difference regarding serum HLA class I antigens was found. DQA1*0101 allele appears significantly in DS-CD + patients and deserves to be searched for in a larger sample to assess its meaning in the DS-CD association.

HIV infection and invasive cervical carcinoma in an Italian population: the need for closer screening programmes in seropositive patients

OBJECTIVE

To evaluate in an Italian population the prevalence, characteristics at first diagnosis and outcome of HIV-seropositive individuals with cervical carcinoma referred to a tertiary-care institution.

DESIGN

A retrospective evaluation of all patients referred for invasive cervical carcinoma from 1991 to 1994.

SETTING

The departments of obstetrics and gynaecology, and radiotherapy at San Gerardo Hospital, University of Milan, Italy.

PATIENTS

A total of 340 women were treated over a 3-year period (186 aged < 50 years). Six patients were found to be HIV-seropositive.

INTERVENTIONS

Seropositive patients were treated according to current institutional protocols, irrespective of HIV status. Four underwent radiotherapy and two radical hysterectomy as primary treatment.

RESULTS

Although five HIV-seropositive patients were known to be infected 13-81 months before diagnosis of cervical cancer, none had received a PAP smear in the last year and only one in the last 2 years. HIV patients were younger than general population (P = 0.02), with a significant history of intravenous drug use (P = 0.000001) and with more advanced disease (P = 0.04). Two HIV-positive patients also received polychemotherapy (one adjuvant and one salvage treatment) and both completed the planned treatment. Within 24 months two patients had died of cancer and one of AIDS; one is alive with AIDS and cancer and two are free of disease.

CONCLUSIONS

This study confirms that in a southern European population, HIV-seropositive women present to tertiary-care institutions with more advanced disease and have a poorer prognosis than the general population. Strict screening programs for cervical dysplasia and cancer are warranted for HIV-seropositive patients.

Pre-operative cervical preparation before first trimester missed abortion: a randomized controlled comparison between single or double intracervical administration of PGE2 gel

The aim of this study was to evaluate whether a single intracervical application of prostaglandin E2 (PGE2) gel is as effective as a repeated administration with respect to the % of curettage for a missed abortion and to incidence of side effects. 32 consecutive patients with ultrasonographic diagnosis of missed abortion from 6th-13th week of gestation were randomly allocated to either single (group A) or repeated, 2 h apart (group B), intracervical application of PGE2 gel. No differences were observed in cervical dilatation before the administration of the gel between the two groups. In group B, evaluation of cervical dilatation 2 h after the first administration of PGE2 gel and before the second one did not show significant changes as compared to baseline values. The degree of cervical dilatation before surgery was significantly improved as compared to the initial dilatation in both groups; no significant difference was observed between the two study groups. A single administration of PGE2 gel followed by surgery 5 h later has the same effectiveness on cervical dilatation but fewer side effects than repeated administration of the drug 2 h apart.

Induction of labor with intravaginal prostaglandin E2 gel

OBJECTIVE

The aim of our study was to evaluate the optimum dose of intravaginal prostaglandin E2 gel for induction for labor in nulliparous women with a relatively ripe cervix (modified Bishop score 4 or 5).

METHOD

One hundred and sixty-seven nulliparous women at term with indications for the induction of labor were treated randomly with two doses of intravaginal 2.0 (group A) or 3.0 mg (group B) of prostaglandin PGE2 gel every 12 h. Data were analyzed by chi 2-test and Student's t-test.

RESULTS

Of 87 patients 64 went into labor after gel application in group A, compared with 68/80 in group B (73.5% vs. 85.0%) (P = NS). A second gel administration was needed for 9 women in group A and 6 women in group B. More side effects (both local and systemic) were noted in group B than in group A (28.7% vs. 14.9%) (P = 0.03). In particular, more local (hyperstimulation or hypertonus) side effects were noted in group B (13.7% vs. 2.3%) (P = 0.01).

CONCLUSION

The vaginal administration of 2.0 mg of PGE2 gel seems to be equally effective as 3.0 mg in terms of labor success rate with a significant lower incidence of side effects.

Inter-ethnic polymorphism of the beta-globin gene locus control region (LCR) in sickle-cell anemia patients

Sequence polymorphisms within the 5'HS2 segment of human locus control region is described among sickle cell anemia patients. Distinct polymorphic patterns of a simple sequence repeat are observed in strong linkage disequilibrium with each of the five major beta s haplotypes. Potential functional relevance of this polymorphic region in globin gene expression is discussed.

Presence of an African beta-globin gene cluster haplotype in normal chromosomes in Sicily

African admixture in Sicily has been long suspected because of the presence of the sickle gene. Nevertheless, the degree of African admixture cannot be derived from the study of HbS frequency, since this gene was most likely expanded by the selective pressure of malaria, for a long time endemic to the region. We have examined 142 individuals from the Sicilian town of Butera (12% sickle trait) to search for other markers of the globin gene cluster less likely to be selected for by malaria. The TaqI polymorphism in the intervening sequences between the two gamma genes is informative. We have found only two instances of this African marker (TaqI(-)) among 267 normal chromosomes, demonstrating that the admixture occurred at a much lower level than previously thought.

Genetic epidemiology of beta-thalassemia in Sicily: do sequences 5' to the G gamma gene and 5' to the beta gene interact to enhance HbF expression in beta-thalassemia?

The present epidemiological study of the molecular characteristics of beta-thalassemia in Sicily was prompted by the disparate phenotypic expression (in clinical status and absolute HbF level) observed in two beta-thalassemic homozygotes who were also homozygous for the beta-like globin gene cluster haplotype III. We suspected that polymorphisms within haplotype III could be the cause for the discrepancy. Based on the association of particular conformations of the (AT)xT(y) motif (-540 5' to the beta gene) with milder forms of thalassemia and sickle cell anemia, 38 homozygous beta-thalassemia patients were studied to define their haplotypes, the -158 site 5' to the G gamma gene (linked to haplotype III) and the structure of the (AT)xT(y) motif. We found that the patient who was phenotypically mild and homozygous for beta-thalassemia, haplotype III, and the -158 C----T mutation was homozygous for the rare (AT)9T5 motif. In contrast, the patient homozygous for beta-thalassemia, haplotype III, and the -158 mutation, but exhibiting a severe clinical course, was homozygous for the (AT)7T7 configuration. Others have suggested that (AT)9T5 is a negative regulatory protein binding sequence, and it is a silent carrier state for beta-thalassemia. The usual configuration (AT)7T7, has considerably less affinity for regulatory protein binding, and it is the most common configuration in Sicilian beta-thalassemics (67 of the 78 chromosomes studied). Within the 38 patients studied, seven were informative because they had various combinations of the (AT)9T5 and (AT)7T7 motif, and the -158 C----T mutation. The results in these patients suggest that only the co-presence of the (AT)9T5 configuration and a C----T change at -158 5' to the G gamma gene is associated with high HbF expression and a mild clinical phenotype. We postulate that these two regions of the beta-like globin gene cluster interact, when endowed with the proper sequences, to enhance the expression of HbF secondary to anemia.

Nucleotide variations in the 3' A gamma enhancer region are linked to beta-gene cluster haplotypes and are unrelated to fetal hemoglobin expression

Molecular cloning and sequence analysis of a nondeletion form of Sicilian beta o hereditary persistence of fetal hemoglobinemia (HPFH) (mutation in IVS2 nt1 position) homozygous for haplotype III revealed the presence of four sequence variations: C----T at -158 5' to G gamma, T----C at +2285, C----A at +2476, and A----G at +2676, all 3' to A gamma. The latter three variations in the putative A gamma enhancer are identical to those observed in the case of Seattle HPFH. However, a severe beta o-thalassemia case from Algeria (mutation in IVS1 nt1 position), also homozygous for haplotype III, revealed the same nucleotide variation, albeit an inefficient HbF production. We conclude that the variations in the A gamma enhancer element do not play a role in the regulation of HbF production. To assess both the linkage of these sites with the beta-cluster haplotype and the extent of the polymorphism, we examined several black and Mediterranean chromosomes, by PCR amplification followed by both EspI digestion and oligonucleotide hybridization. Our data indicate that these sequence variations in the enhancer element are absent in Mediterranean haplotypes I, V, and VII but are consistently associated with Mediterranean haplotypes II, III, and IX, as well as with the black beta c-associated haplotype. The common feature of all the latter haplotypes is the presence of a polymorphic PvuII site between A gamma and psi beta, which is thus in linkage disequilibrium with the variations in the A gamma enhancer.(ABSTRACT TRUNCATED AT 250 WORDS)

The enhancer-like sequence 3' to the A gamma gene is polymorphic in human populations

Cloning and sequencing of the enhancer 3' of the A gamma globin gene of a particularly low G gamma and HbF sickle cell anemia (SCA) patient unexpectedly revealed three base changes (T----C, C----A, and A----G at sites +2285, +2460, and +2676) previously associated with the Seattle-type HPFH, thus leading the authors to suspect that the three mutations were polymorphic. The determination of the incidence of the mutations among various ethnic groups allowed the authors to conclude that this is a widely spread polymorphism, thus excluding any role of these base changes in the determination of the hereditary persistence of fetal hemoglobin (HPFH) phenotype. The origin of these three mutations is not clear because they appear linked, and the same bases (C, A, G) are found in homologous position in the 3' of the normal G gamma gene. As C, A, G at positions +2285, +2460, and +2676 are found with a 100% frequency in African SS patients and presumably among normal Africans (to explain the extremely high frequency among normal American blacks), it is likely that this was the sequence preceding the division of races. The presence of T, C, and A at the same positions apparently occurred after the divergence between blacks and the other races, that is, within the last 1 million years.

Beta S gene in Sicily is in linkage disequilibrium with the Benin haplotype: implications for gene flow

Hemoglobin beta-like gene cluster haplotypes defined by restriction enzyme polymorphic sites are useful in determining the origin of the beta S gene found in several human populations. We present here evidence that the beta S gene found among Sicilians is associated with the same haplotype observed among sickle cell anemia patients from Central West Africa. In addition, this haplotype is either nonexistent or very rare among normal Sicilian individuals. We conclude that the beta S gene was introduced to Sicily from North Africa and that the gene flow originated in Central West Africa and traveled north through historically well-defined trans-Saharan commercial routes.