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A Carbonara

Publications and source records attributed to A Carbonara.

At least 19 recordsLinked to original sources

Intra-abdominal extra lobar pulmonary sequestration communicating with gastric duplication -- a case report.

Gastric duplications with associated pulmonary sequestration are very infrequent abnormalities. Although often asymptomatic, they should be considered in the differential diagnosis of intra-abdominal or retro-peritoneal masses. The authors report the case of a ten-year-old boy who had an occasional finding of poorly symptomatic intra-abdominal mass, recognised at intervention as a gastric duplication with associated extralobar pulmonary sequestration. The authors describe the surgical treatment of this case and briefly discuss the current views on the embryological pathogenesis of such malformations.

Bronchopulmonary Sequestration↗

Influence of smoking habits on Down's syndrome risk evaluation at mid-trimester through biochemical screening.

Expectant mothers who smoke have higher levels of maternal serum alpha-fetoprotein and lower levels of unconjugated estriol and total human chorionic gonadotrophin than non-smoking mothers. This significantly affects performance of screening for Down's syndrome. This study includes 22,169 pregnant women: 18,876 non-smokers, 2,660 smoking < or = 10 cigarettes/day, and 633 smoking > 10 cigarettes/day. Mean maternal age (32.6 years), maternal weight (60.5 kg), and gestational age (114.7 days) were similar or only slightly different between the three groups. To verify the effects of smoking on screening, we studied retrospectively 130 sequential Down's syndrome cases (47 from the screening program, 83 from the prenatal diagnosis program). The proportion of smokers in the Down's syndrome and unaffected pregnancies was similar, whilst the false-positive rate and detection rate, based on fetal outcome, differed: false-positive rates were 5.63% in smokers and 9.42% in non-smokers, and detection rate 55.6% in smokers and 83.0% in non-smokers. Since the prevalence of Down's syndrome pregnancies was the same at mid-trimester in smokers and non-smokers and the proportion of smokers was not related to maternal age, we propose an adjustment of the Down's syndrome risk evaluation algorithm according to smoking habits.

Adult↗

Repeat testing of mothers with high human chorionic gonadotrophin levels in Down's syndrome screening.

Multiples of medians of serum markers are assumed to be independent of gestational age: every algorithm used for Down's syndrome risk evaluation is based on this hypothesis. However, our former observations suggested that multiples of medians of human chorionic gonadotrophin in Down's syndrome are dependent on gestatational age. Furthermore, observations on 84 Down's syndrome cases confirmed that human chorionic gonadotrophin multiples of medians in samples drawn at 15-17 weeks are approximately 10% lower than in samples drawn at 18-21 weeks, thus showing that the human chorionic gonadotrophin concentration decreases about 10% less than expected. The control group comprised 554 women with two blood samples and normal human chorionic gonadotrophin at first sampling. A further group of 532 women with multiples of medians at first sampling > 1.8 was examined with the aim of excluding an association between the human chorionic gonadotrophin trend in Down's syndrome and high starting values. The trend is peculiar to human chorionic gonadotrophin in Down's syndrome pregnancies and may help to explain the increase in detection rate with gestational age. Based on these findings, screening can be optimized, thus improving performance.

Adult↗

Autosomal dominant polycystic kidney disease (ADPKD) in an Italian family carrying a novel nonsense mutation and two missense changes in exons 44 and 45 of the PKD1 Gene.

Sixty-seven Italian patients with autosomal dominant polycystic kidney disease (ADPKD) were screened for mutations in the 3' unique region of the PKD1 gene, using heteroduplex DNA analysis. Novel aberrant bands were detected in 3 patients from the same family. DNA sequencing showed a C to T transition in exon 44 (C12269T), resulting in a premature stop codon (R4020X), predicted to impair the synthesis of the putative intracytoplasmic C-terminus tail of the PKD1 protein, polycystin. The mutation also generates a novel DdeI restriction site, and the abnormal restriction pattern was observed both on genomic DNA and on cDNA from the affected relatives, indicating that this is indeed the pathogenetic molecular lesion. Reverse transcriptase-polymerase chain reaction (RT-PCR) performed on lymphocyte mRNA showed that the mutant transcript is normally present and stable. No aberrantly spliced mRNAs were detected. Interestingly, the mutant PKD1 chromosome in this family also bears two missense mutations downstream (A12341G and C12384T), not found in the other ADPKD families studied.

Adolescent↗

Prenatal diagnosis of limb-girdle muscular dystrophy type 2A.

A branch of a highly inbred family was referred for prenatal counseling with an initial misdiagnosis of Becker Muscular Dystrophy (BMD) due to the limited clinical and laboratory data obtained in pre-dystrophin era and hidden family information. In a second branch of the family with a diagnosis of limb-girdle muscular dystrophy type 2A (LGMD2A) molecular studies revealed a homozygous 550 delta A mutation in the calcium-activated neutral protease 3 (calpain 3, CANP3) gene in the affected members. Finally, in the third branch of the family, it turned out that both parents were heterozygous for the 550 delta A mutation and the 13-week-old fetus was homozygous. The same mutation subsequently also was found in the first branch of the family. The parents were informed that the risk of their child of developing the disease would be very high given that he was carrying the same homozygous mutation of the other affected members. They were informed also that in another population (in Reunion Island) the same disease does not necessarily follow such a simple pattern of inheritance. After counseling the parents decided to terminate the pregnancy.

Adult↗

Detection of two different nonsense mutations in exon 44 of the PKD1 gene in two unrelated Italian families with severe autosomal dominant polycystic kidney disease.

Sixty-seven Italian patients with autosomal dominant polycystic kidney disease (ADPKD) were screened for mutations in the PKD1 gene. We used PCR, heteroduplex and single-strand conformation polymorphism DNA analysis, and automated DNA sequencing for exons 35, 36, 38, 44 and 45. We detected abnormal heteroduplexes in affected individuals from two unrelated families with clinically severe ADPKD phenotype. These changes were absent in other, unaffected members, as well as in the probands of the other families studied. DNA sequencing revealed in both cases different C to T transitions in exon 44, which created premature stop codons. Both mutations altered restriction sites, and the abnormal patterns were observed in all the affected family members. RT-PCR performed on lymphocyte mRNA showed that both the mutant and the normal transcript are represented. To our knowledge these are the first nonsense mutations described in the PKD1 gene.

Exons↗

Pattern dystrophies of the retinal pigment epithelium.

Pattern dystrophies of the retinal pigment epithelium are infrequent fundus abnormalities arranged in various patterns of dots, lines and branches. The basic lesion appears to be yellow deposits of abnormal lipofuscin accumulated within degenerated retinal pigment epithelium cells. Examinations were carried out on two families who had developed different patterned alterations in the retinal pigment epithelium. The proband of family 1 had diffuse changes associated with equatorial folds. One sister had a macular alteration. A daughter was normal; a son had bilateral atrophy of the temporal retinal pigment epithelium. The proband of family 2 had bilateral, symmetrical retinal pigment epithelium lesions that simulated fundus flavimaculatus. His first daughter had a central lesion in her right eye. The second daughter, a peripapillary crescent of hyperpigmentation in her right eye, and circumpapillary chorioretinal atrophy associated with foveolar abnormalities in the left. This report provides further evidence that variable types of pattern dystrophy can occur within a single family pedigree and support the current opinion that all forms of pattern dystrophies are variants of a single pathogenic mechanism.

Adult↗

Carrier detection of Duchenne muscular dystrophy through analysis of DNA from deciduous teeth of a dead affected child.

The sister of a child affected by Duchenne muscular dystrophy (DMD) was referred for genetic counselling to assess the risk of her being a carrier. Her brother had died 15 years previously at the age of 8. There were no other affected males in the family. There were no methods for DNA investigation at the time of the child's death and the family had never been studied for linkage with polymorphic probes on the chromosomal region Xp21. The only tissue from which an assessment of the risk could be made by DNA linkage analysis was two of the child's deciduous teeth that the parents had kept. DNA was extracted using a protocol described for the recovery of ancient DNA from museum specimens and archaeological finds. Multiplex amplification did not reveal deletions in 19 exons spanning the hot-spot regions for deletions within the dystrophin gene in Xp21. Linkage analysis using three highly polymorphic microsatellites demonstrated that the sister had not received the X chromosome borne by her brother. These results show that DNA extracted from teeth is a reliable source for molecular diagnosis.

Child↗

Validation of IgA1 and IgA2 measurements by a solid-phase immunoradiometric assay in serum and secretions.

We describe specific, sensitive and reproducible immunoradiometric assays to measure total IgA and IgA subclass levels in biological fluids, which take into account the problem that polymeric forms are differently recognized in immunoassays. Sera from subjects totally deficient in one of the IgA subclasses allowed us to ensure the specificity of the subclass assays and to define the proportions of IgA1 (84%) and IgA2 (16%) in the normal pooled serum (from 30 blood donors) used as standard. With purified milk 11-S secretory IgA1 and 11-S secretory IgA2, we determined a correction factor for the corresponding polymeric forms using, respectively, monomeric IgA1 and monomeric IgA2 from pooled serum as standards. With the monoclonal antibodies used, purified 11-S secretory IgA1 was similarly recognized by both the total IgA assay and the IgA1 assay; both total IgA and IgA1 concentrations were underestimated compared with monomeric IgA or monomeric IgA1. In contrast, 11-S secretory IgA2 was better recognized by the IgA2 assay than by the total IgA assay and the values were thus overestimates. Considering this problem of recognition, we fractionated saliva and lung secretions by sucrose density gradient ultracentrifugation before measuring their IgA1 and IgA2 levels.

Adult↗

Dilating cardiomyopathy as the expression of Xp21 Becker type muscular dystrophy.

A 35-year-old man with severe progressive dilating cardiomyopathy and no clinical signs of muscle disease underwent muscular investigations because of markedly increased serum creatine kinase. Muscle biopsy demonstrated Becker type muscular dystrophy with dystrophin of low molecular weight. Genetic analysis showed a deletion spanning from exon 45 to exon 46 in the Xp21 region. Xp21 Becker type muscular dystrophy must be considered in the differential diagnosis of dilating cardiomyopathy.

Adult↗

Analysis of CA/GT microsatellite polymorphism in IVS8 of the cystic fibrosis transmembrane conductance regulator (CFTR) gene: a study of Italian CF families.

Forty-six CF Italian patients and their parents were screened for a highly polymorphic microsatellite consisting of a variable number of CA/GT repeats in intron 8 of the CFTR gene. A strong degree of association was found between alleles 2 and 6 and the CF mutation delta F508. Moreover, considering the haplotypes at the closely linked locus D7S23 and the microsatellite's alleles, a strong linkage disequilibrium was again found for delta F508 and also for non-delta F508 CF chromosomes and the eight commonest haplotypes (B2, B6, C7, A6, A7, B7, D2 and D7). These data, compared with those described in the Spanish population, further support the common origin of the delta F508 mutation in Southern European populations.

Alleles↗

Recurrent mutations and three novel rearrangements in the factor VIII gene of hemophilia A patients of Italian descent.

Hemophilia A (HA), a common inherited bleeding disorder in humans, is due to the deficiency or absence of the factor VIII (FVIII) activity. The cloning of the FVIII gene has made molecular probes available for the characterization of the basic defect in this disease. In this study we describe six different mutations in the FVIII gene detected by DNA analysis of 100 HA patients of Italian descent. In two of them, with a severe clinical picture, we identified two novel deletions, one in the middle of the FVIII gene from exons 7 to 22 and the other encompassing the entire factor VIII gene. Both of these patients produced antibodies to factor VIII. In a patient with mild HA we detected a duplication of exon 13, which is a rearrangement not yet described within the FVIII gene. A possible explanation for the mild phenotype in this patient is that the molecular defect results in the production of an unstable FVIII protein with residual 10% FVIII activity. Screening by Taq I restriction endonuclease detected three mutations that were further characterized by direct sequencing on amplified DNA: a C-T substitution at codon 1960, in exon 18, converting the codon for arginine to a non-sense codon; and a G-A substitution at codon 2228 and 2326, in exons 24 and 26 respectively, resulting in the substitution of glutamine for arginine. All three of these mutations have been previously described. The non-sense mutation and the codon 2228 G-A mutation was found in patients with severe HA, while the codon 2326 G-A mutation was associated with a quite severe condition. These results confirm that the molecular bases of HA are very heterogeneous and provide further evidence that recurrent mutations are not uncommon in this system.

Base Sequence↗

Autosomal dominant polycystic kidney disease: a linkage evaluation of heterogeneity in Italy. Italian Collaborative Group on Polycystic Kidney Disease.

A survey of 29 families with Adult Polycystic Kidney Disease (ADPKD) was performed to evaluate the genetic heterogeneity of the disease in Italy. The approach was through the linkage between the disease and 2 polymorphic DNA fragments as detected by the probes 3'HVR and 24.1. Linkage between the polymorphic markers and the disease was confirmed, with the following lod scores: between 3'HVR and ADPKD1 = 12.974 at theta = 0.02; between 24.1 and ADPKD = 1.716 at theta = 0.07; between 3'HVR and 24.1 = 2.738 at theta = 0.09. No evidence of significant genetic heterogeneity in the examined Italian regions was detected.

Genes, Dominant↗

Anti-HLA-B7,B27,Bw42,Bw54,Bw55,Bw56, Bw67,Bw73 monoclonal antibodies: specificity, idiotypes, and application for a double determinant immunoassay.

The monoclonal antibodies (MoAbs) KS3 and KS4 are secreted by hybridomas constructed with splenocytes from a BALB/c mouse sequentially immunized with the cultured lymphoid cells JKu and LG-2 which share only the HLA-B27 specificity. Serologic and immunochemical assays have shown that the two MoAbs recognize the same (or spatially close) determinant expressed by HLA-B7,B27,Bw42,Bw54,Bw55,Bw56,Bw67, and Bw73 alloantigens. This determinant is spatially close but distinct from those defined by the anti HLA-B27 monoclonal antibodies described in the literature. The syngeneic antiidiotypic MoAb T12-105 and T12-211 elicited with MoAb KS4 were shown to recognize idiotopes within the antigen combining site of MoAb KS3 and KS4. Neither idiotope was detected on the anti HLA class I and anti HLA class II monoclonal antibodies tested. The MoAb KS4 in combination with the anti human beta 2-microglobulin MoAb NAMB-1 was utilized to develop a double determinant immunoassay (DDIA). The latter represents a sensitive method to detect and quantitate HLA-B27 antigens in spent culture medium of lymphoid cell lines and in serum. Typing for HLA-B27 antigens with the DDIA of sera from HLA typed donors yielded results highly correlated with those of the conventional lymphocytotoxicity assay.

Antibodies, Monoclonal↗

A double determinant immunoassay for HLA class I typing using serum as an antigen source.

We have applied a double determinant immunoassay (DDIA) to HLA-A2,A28, and B13 typing, using serum as an antigen source. The results obtained show a correlation of 96% (B13) and 89.1% (A2,A28) with the results obtained by conventional HLA typing. Furthermore, the results obtained were highly reproducible, since testing of 18 sera on two occasions gave concordant results with all samples tested. The variation in the content of HLA-A2 antigens in sera taken at different times from a given donor was less than 5%. A sevenfold variation was found in the serum level of HLA-A2,A28 antigens: the highest level was found in the sera from HLA-A2,A28 donors and in decreasing order in HLA-A2 homozygous, HLA-A28 homozygous, HLA-A2 heterozygous, and HLA-A28 heterozygous donors. The results of this study indicate that the DDIA is a sensitive, simple, and reproducible procedure for HLA class I typing. The DDIA offers the following advantages in comparison with the conventional lymphocytotoxic assay: it provides information not only about the expression of a given alloantigen, but also about its level; it does not require viable cells, thus facilitating retrospective studies and typing of leucopenic patients; it eliminates variability of results caused by abnormal susceptibility of target cells to complement-dependent lysis.

Antibodies, Monoclonal↗