Olfactory receptor genes and chromosome 11 structural aberrations: Players or spectators?

The largest multi-gene family in metazoans is the family of olfactory receptor (OR) genes. Human ORs are organized in clusters over most chromosomes and seem to include >0.1% the human genome. Because 369 out of 856 OR genes are mapped on chromosome 11 (HSA11), we sought to determine whether they mediate structural rearrangements involving this chromosome. To this aim, we analyzed 220 specimens collected during diagnostic procedures involving structural rearrangements of chromosome 11. A total of 222 chromosomal abnormalities were included, consisting of inversions, deletions, translocations, duplications, and one insertion, detected by conventional chromosome analysis and/or fluorescence in situ hybridization (FISH) and array comparative genomic hybridization (array-CGH). We verified by bioinformatics and statistical approaches the occurrence of breakpoints in cytobands with or without OR genes. We found that OR genes are not involved in chromosome 11 reciprocal translocations, suggesting that different DNA motifs and mechanisms based on homology or non-homology recombination can cause chromosome 11 structural alterations. We also considered the proximity between the chromosomal territories of chromosome 11 and its partner chromosomes involved in the translocations by using the deposited Hi-C data concerning the possible occurrence of chromosome interactions. Interestingly, most of the breakpoints are located in regions highly involved in chromosome interactions. Further studies should be carried out to confirm the potential role of chromosome territories' proximity in promoting genome structural variation, so fundamental in our understanding of the molecular basis of medical genetics and evolutionary genetics.

Genomic Complexity and Complex Chromosomal Rearrangements in Genetic Diagnosis: Two Illustrative Cases on Chromosome 7

Complex chromosomal rearrangements are rare events compatible with survival, consisting of an imbalance and/or position effect of one or more genes, that contribute to a range of clinical presentations. The investigation and diagnosis of these cases are often difficult. The interpretation of the pattern of pairing and segregation of these chromosomes during meiosis is important for the assessment of the risk and the type of imbalance in the offspring. Here, we investigated two unrelated pediatric carriers of complex rearrangements of chromosome 7. The first case was a 2-year-old girl with a severe phenotype. Conventional cytogenetics evidenced a duplication of part of the short arm of chromosome 7. By array-CGH analysis, we found a complex rearrangement with three discontinuous trisomy regions (7p22.1p21.3, 7p21.3, and 7p21.3p15.3). The second case was a newborn investigated for hypodevelopment and dimorphisms. The karyotype analysis promptly revealed a structurally altered chromosome 7. The array-CGH analysis identified an even more complex rearrangement consisting of a trisomic region at 7q11.23q22 and a tetrasomic region of 4.5 Mb spanning 7q21.3 to q22.1. The mother's karyotype examination revealed a complex rearrangement of chromosome 7: the 7q11.23q22 region was inserted in the short arm at 7p15.3. Finally, array-CGH analysis showed a trisomic region that corresponds to the tetrasomic region of the son. Our work proved that the integration of several technical solutions is often required to appropriately analyze complex chromosomal rearrangements in order to understand their implications and offer appropriate genetic counseling.

A DNA damage response-like phenotype defines a third of colon cancers at onset

Colon adenocarcinoma (COAD) has a limited range of diversified, personalized therapeutic opportunities, besides DNA hypermutating cases; thus, both new targets or broadening existing strategies for personalized intervention are of interest. Routinely processed material from 246 untreated COADs with clinical follow-up was probed for evidence of DNA damage response (DDR), that is, the gathering of DDR-associated molecules at discrete nuclear spots, by multiplex immunofluorescence and immunohistochemical staining for DDR complex proteins (γH2AX, pCHK2, and pNBS1). We also tested the cases for type I interferon response, T-lymphocyte infiltration (TILs), and mutation mismatch repair defects (MMRd), known to be associated with defects of DNA repair. FISH analysis for chromosome 20q copy number variations was obtained. A total of 33.7% of COAD display a coordinated DDR on quiescent, non-senescent, non-apoptotic glands, irrespective of TP53 status, chromosome 20q abnormalities, and type I IFN response. Clinicopathological parameters did not differentiate DDR+ cases from the other cases. TILs were equally present in DDR and non-DDR cases. DDR+ MMRd cases were preferentially retaining wild-type MLH1. The outcome after 5FU-based chemotherapy was not different in the two groups. DDR+ COAD represents a subgroup not aligned with known diagnostic, prognostic, or therapeutic categories, with potential new targeted treatment opportunities, exploiting the DNA damage repair pathways.

Positive predictive values and outcomes for uninformative cell-free DNA tests: An Italian multicentric Cytogenetic and cytogenomic Audit of diagnOstic testing (ICARO study)

OBJECTIVES

To establish the positive predictive values (PPV) of cfDNA testing based on data from a nationwide survey of independent clinical cytogenetics laboratories.

METHODS

Prenatal diagnostic test results obtained by Italian laboratories between 2013 and March 2020 were compiled for women with positive non-invasive prenatal tests (NIPT), without an NIPT result, and cases where there was sex discordancy between the NIPT and ultrasound. PPV and other summary data were reviewed.

RESULTS

Diagnostic test results were collected for 1327 women with a positive NIPT. The highest PPVs were for Trisomy (T) 21 (624/671, 93%) and XYY (26/27, 96.3%), while rare autosomal trisomies (9/47, 19.1%) and recurrent microdeletions (8/55, 14.5%) had the lowest PPVs. PPVs for T21, T18, and T13 were significantly higher when diagnostic confirmation was carried out on chorionic villi (97.5%) compared to amniotic fluid (89.5%) (p < 0.001). In 19/139 (13.9%), of no result cases, a cytogenetic abnormality was detected. Follow-up genetic testing provided explanations for 3/6 cases with a fetal sex discordancy between NIPT and ultrasound.

CONCLUSIONS

NIPT PPVs differ across the conditions screened and the tissues studied in diagnostic testing. This variability, issues associated with fetal sex discordancy, and no results, illustrate the importance of pre- and post-test counselling.

Possible Use of Minocycline in Adjunction to Intranasal Esketamine for the Management of Difficult to Treat Depression following Extensive Pharmacogenomic Testing: Two Case Reports

The advent of intra-nasal esketamine (ESK), one of the first so called fast-acting antidepressant, promises to revolutionize the management of treatment resistant depression (TRD). This NMDA receptor antagonist has proven to be rapidly effective in the short- and medium-term course of the illness, revealing its potential in targeting response in TRD. Although many TRD ESK responders are able to achieve remission, a considerable portion of them undergo a metamorphosis of their depression into different clinical presentations, characterized by instable responses and high recurrence rates that can be considered closer to the concept of Difficult to Treat Depression (DTD) than to TRD. The management of these DTD patients usually requires a further complex multidisciplinary approach and can benefit from the valuable contribution of new personalized medicine tools such as therapeutic drug monitoring and pharmacogenetics. Despite this, these patients usually come with long and complex previous treatments history and, often, advanced and sophisticated ongoing pharmacological schemes that can make the finding of new alternative options to face the current recurrences extremely challenging. In this paper, we describe two DTD patients—already receiving intranasal ESK but showing an instable course—who were clinically stabilized by the association with minocycline, a semisynthetic second-generation tetracycline with known and promising antidepressant properties.

Characterization of Chromosomal Breakpoints in 12 Cases with 8p Rearrangements Defines a Continuum of Fragility of the Region

Improvements in microarray-based comparative genomic hybridization technology have allowed for high-resolution detection of genome wide copy number alterations, leading to a better definition of rearrangements and supporting the study of pathogenesis mechanisms. In this study, we focused our attention on chromosome 8p. We report 12 cases of 8p rearrangements, analyzed by molecular karyotype, evidencing a continuum of fragility that involves the entire short arm. The breakpoints seem more concentrated in three intervals: one at the telomeric end, the others at 8p23.1, close to the beta-defensin gene cluster and olfactory receptor low-copy repeats. Hypothetical mechanisms for all cases are described. Our data extend the cohort of published patients with 8p aberrations and highlight the need to pay special attention to these sequences due to the risk of formation of new chromosomal aberrations with pathological effects.

Instability of Short Arm of Acrocentric Chromosomes: Lesson from Non-Acrocentric Satellited Chromosomes. Report of 24 Unrelated Cases

Satellited non-acrocentric autosomal chromosomes (ps–qs-chromosomes) are the result of an interchange between sub- or telomeric regions of autosomes and the p arm of acrocentrics. The sequence homology at the rearrangement breakpoints appears to be, among others, the most frequent mechanism generating these variant chromosomes. The unbalanced carriers of this type of translocation may or may not display phenotypic abnormalities. With the aim to understand the causative mechanism, we revised all the ps–qs-chromosomes identified in five medical genetics laboratories, which used the same procedures for karyotype analysis, reporting 24 unrelated cases involving eight chromosomes. In conclusion, we observed three different scenarios: true translocation, benign variant and complex rearrangement. The detection of translocation partners is essential to evaluate possible euchromatic unbalances and to infer their effect on phenotype. Moreover, we emphasize the importance to perform both, molecular and conventional cytogenetics methods, to better understand the behavior of our genome.

Testing single/combined clinical categories on 5110 Italian patients with developmental phenotypes to improve array-based detection rate

Background

Chromosomal microarray analysis (CMA) is nowadays widely used in the diagnostic path of patients with clinical phenotypes. However, there is no ascertained evidence to date on how to assemble single/combined clinical categories of developmental phenotypic findings to improve the array‐based detection rate.

Methods

The Italian Society of Human Genetics coordinated a retrospective study which included CMA results of 5,110 Italian patients referred to 17 genetics laboratories for variable combined clinical phenotypes.

Results

Non‐polymorphic copy number variants (CNVs) were identified in 1512 patients (30%) and 615 (32%) present in 552 patients (11%) were classified as pathogenic. CNVs were analysed according to type, size, inheritance pattern, distribution among chromosomes, and association to known syndromes. In addition, the evaluation of the detection rate of clinical subgroups of patients allowed to associate dysmorphisms and/or congenital malformations combined with any other single clinical sign to an increased detection rate, whereas non‐syndromic neurodevelopmental signs and non‐syndromic congenital malformations to a decreased detection rate.

Conclusions

Our retrospective study resulted in confirming the high detection rate of CMA and indicated new clinical markers useful to optimize their inclusion in the diagnostic and rehabilitative path of patients with developmental phenotypes.

A new case report of severe mucopolysaccharidosis type VII: diagnosis, treatment with haematopoietic cell transplantation and prenatal diagnosis in a second pregnancy

A new patient with severe mucopolysaccharidosis (MPS) type VII is reported. Non-immune hydrops fetalis (NIHF) was diagnosed during pregnancy. At birth, he showed generalized hydrops and dysmorphic features typical of MPS. Many diagnoses were excluded before reaching the diagnosis of MPS VII at 8 months of life. During the first year of life he had frequent respiratory infections associated with restrictive and obstructive bronchopneumopathy and underwent three surgical interventions: decompression of the spinal cord at the craniocervical junction, bilateral inguinal hernia, and bilateral clubfoot. At 14 months of life he underwent successful haematopoietic cell transplantation (HCT). During the following 10 months, his bronchopneumopathy progressively worsened, needing chronic pharmacological treatment and O₂ administration. The patient died of respiratory insufficiency during a respiratory syncytial virus infection at 25 months of age. Molecular analysis showed the homozygous variant c.1617C > T, leading to the synonymous mutation p.Ser539=. This caused aberrant splicing with partial skipping of exon 10 (r.1616_1653del38) and complete skipping of exon 9 (r.1392_1476del85; r.1616_1653del38). No transcript of normal size was evident. The parents were both confirmed to be carriers. In a subsequent pregnancy, a prenatal diagnosis showed an affected fetus. Ultrasound examination before abortion showed NIHF. The skin and placenta examination by electron microscopy showed foamy intracytoplasmic vacuoles with a weakly electron-dense substrate. MPS VII is a very rare disease but it is possible that some cases go undiagnosed for several reasons, including that MPS VII, and other lysosomal storage diseases, are not included in the work-up for NIHF in many institutions, and the presence of anasarca at birth may be confounding for the recognition of the typical facial characteristics of the disease. This is the eighth patient affected by MPS VII who has undergone HCT. It is not possible to draw conclusions about the efficacy of HCT in MPS VII. Treatment with enzyme replacement is now available and will probably be beneficial for the patients who have a milder form with no or little cognitive involvement. Increased awareness among clinicians is needed for prompt diagnosis and to offer the correct treatment as early as possible.

Familiar unbalanced complex rearrangements involving 13 p-arm: description of two cases

Background

Copy number variations (CNVs) are largely known today, but their position is rarely established by fluorescence in situ hybridization (FISH) or karyotype analysis.

Case presentation

We described two families with copy number gain in which FISH analysis with the specific subtelomeric probe of chromosome 4q and 7q evidenced a third signal at band 13p11.2. Genomic study by array comparative genomic hybridization defined the triple dose segment. In the first case, the duplicate tract is free of known genes, in the second one it contained three expressed genes.

Conclusions

The CNV localization on the short arm of an acrocentric chromosome could explain the lack of phenotypic effect, being known the regulatory role of heterochromatin in the position-effect silencing. Furthermore, we would like to underline the importance of using complementary techniques such as FISH and array-CGH to obtain a better definition of genomic rearrangements.

Molecular cytogenetics characterization of seven small supernumerary marker chromosomes derived from chromosome 19: Genotype-phenotype correlation and review of the literature

Only a few subjects carrying supernumerary marker chromosomes derived from 19 chromosome (sSMC(19)) have been described to date and for a small portion of them the genic content has been defined at the molecular level. We present seven new different sSMCs(19) identified in eight individuals, seven of whom unrelated. The presence of the sSMC is associated with a clinical phenotype in five subjects, while the other three carriers, two of whom related, are normal. All sSMCs(19) have been characterized by means of conventional and molecular cytogenetics. We compare the sSMCs(19) carriers with a clinical phenotype to already described patients with gains (sSMCs or microduplications) of overlapping genomic regions with the aim to deepen the pathogenicity of the encountered imbalances and to assess the role of the involved genes on the phenotype. The present work supports the correlation between the gain of some chromosome 19 critical regions and specific phenotypes.

A complete duplication of X chromosome resulting in a tricentric isochromosome originated by centromere repositioning

BACKGROUND

Neocentromeres are rare and considered chromosomal aberrations, because a non-centromeric region evolves in an active centromere by mutation. The literature reported several structural anomalies of X chromosome and they influence the female reproductive capacity or are associated to Turner syndrome in the presence of monosomy X cell line.

CASE PRESENTATION

We report a case of chromosome X complex rearrangement found in a prenatal diagnosis. The fetal karyotype showed a mosaicism with a 45,X cell line and a 46 chromosomes second line with a big marker, instead of a sex chromosome. The marker morphology and fluorescence in situ hybridization (FISH) characterization allowed us to identify a tricentric X chromosome constituted by two complete X chromosome fused at the p arms telomere and an active neocentromere in the middle, at the union of the two Xp arms, where usually are the telomeric regions. FISH also showed the presence of a paracentric inversion of both Xp arms. Furthermore, fragility figures were found in 56% of metaphases from peripheral blood lymphocytes culture at birth: a shorter marker chromosome and an apparently acentric fragment frequently lost.

CONCLUSIONS

At our knowledge, this is the first isochromosome of an entire non-acrocentric chromosome. The neocentromere is constituted by canonical sequences but localized in an unusual position and the original centromeres are inactivated. We speculated that marker chromosome was the result of a double rearrangement: firstly, a paracentric inversion which involved the Xp arm, shifting a part of the centromere at the p end and subsequently a duplication of the entire X chromosome, which gave rise to an isochromosome. It is possible to suppose that the first event could be a result of a non-allelic homologous recombination mediated by inverted low-copy repeats. As expected, our case shows a Turner phenotype with mild facial features and no major skeletal deformity, normal psychomotor development and a spontaneous development of puberty and menarche, although with irregular menses since the last follow-up.

19q12q13.2 duplication syndrome: neuropsychiatric long-term follow-up of a new case and literature update

Genetic syndromes are well characterized by the phenotypic point of view, but little is known about their progression and patients' quality of life. We report a 10-year neuropsychiatric follow-up of a boy with duplication of chromosome 19. Cytogenetic investigation was requested at the age of 5 years for psychomotor and speech delay. The genomic study identified an 8.17 Mb duplication on chromosome 19q12q13.2. We propose that the long-term follow-up of our patient would help to delineate the neuropsychiatric phenotype associated with 19q duplication. This study could be a model for further long-term research in the neuropsychiatric follow-up of patients with 19q duplication syndrome.

14q32.3-qter trisomic segment: a case report and literature review

BACKGROUND

Segmental duplication of the long arm of chromosome 14 (14q) has commonly been reported to affect the proximal segment of 14q, while distal duplication is a rare condition and often associated with segmental monosomy of other chromosomes.

CASE PRESENTATION

We report the clinical and genetic characterization of a 4-year-old male patient with 14q32.3-qter trisomy resulting from an adjacent segregation of a paternal reciprocal translocation (14;21)(q32.1;p12). The child shows minor facial anomalies, severe developmental delay, growth retardation, and a history of congenital hypothyroidism and neonatal transitory hyperglycemic crises.

CONCLUSIONS

To the best of our knowledge, only 15 other cases of segmental 14q trisomy were documented. We compared molecularly defined cases to identify a minimal common duplicated region and to find genes with a hypothetical role in the phenotype. The presented case supports the previous suggestion of a pure "distal 14q partial duplication" and underlines the clinical variability.

Interstitial 11q deletion: genomic characterization and neuropsychiatric follow up from early infancy to adolescence and literature review

BACKGROUND

Interstitial deletions of chromosome 11 long arm are rarely observed and the associated phenotype ranges from normal to severe, depending on the position and size of the deletion and on the presence of unmasked recessive genes on the normal homologous. To our knowledge 32 cases are reported in literature with three family cases. Phenotype-genotype correlation is not very clear and the most common features are characteristic facial dysmorphisms, palate anomalies and developmental delay. Growth retardation is not typical and other major malformations are reported in some cases.

CASE PRESENTATION

We described a child with 11q interstitial deletion diagnosed at birth with hypotonia and minor dysmorphisms using standard cytogenetic techniques; array CGH was subsequently performed to define the deletion at a molecular level.

CONCLUSIONS

This case gave us the opportunity to attempt a genotype-phenotype correlation reviewing the literature and to describe a rehabilitative program that improved the development perspectives of this child.

Lymph node hyperplasia: clonal chromosomal and genomic rearrangements. Report of two new cases and literature review

Cytogenetic analysis is not routinely performed on lymph node hyperplasia (LH). We describe clonal chromosomal rearrangements in two unrelated cases of LH. Lymph nodes of both patients showed typical morphologic features of benign follicular hyperplasia. Cytogenetic analysis revealed clonal chromosomal rearrangements in both cases. Patient 1 showed interstitial 14q and 6q mosaic deletions, whereas patient 2 showed a terminal 14q mosaic deletion. Fluorescence in situ hybridization with IGH break-apart probes identified a partial deletion of IGH in both cases, but the loss of the LSI IGH in patient 2 and loss of the LSI IGHV in patient 1 were observed on the morphologically normal chromosome 14. In the latter case, the finding of two morphologically normal chromosomes 14 with the IGHV deletion in one of the chromosomes suggested that the first mutational event was the IGH deletion and the second event was the interstitial deletion of chromosome 14 with the IGH intact. Array comparative genomic hybridization performed on both biopsies confirmed the IGH deletion at mosaic, but not the chromosomal deletion. Patient 1 was re-biopsied after 9 months and a marginal zone lymphoma was diagnosed. The finding of clonal cytogenetic abnormalities in LH highlighted the difficulties in interpretation of results and clinical follow-up.

Esophageal eosinophilia after radiofrequency ablation for Barrett's esophagus

Radiofrequency ablation (RFA) with HALO system has been developed as a new treatment option for Barrett's esophagus (BE). It had been observed that some patients had esophageal eosinophilia (EE) infiltration after RFA. The incidence and features of EE after RFA were systematically determined. From a prospectively compiled database, data on 148 patients who underwent RFA for BE were analyzed. Biopsies were taken pre- and post-RFA from the BE segment, and histological sections of the biopsy specimens were stained with hematoxylin and eosin, and examined by a gastrointestinal pathologist. The incidence of EE post-RFA was then determined. Of the 148 patients, 120 (81%) were men, 137 (92%) were white, 64 (43%) were overweight and 49 (33%) obese, and 128 (86%) were over 50 years of age or more. Four (2.7%) of the patients developed post-RFA EE, but none had symptoms of eosinophilic esophagitis. All patients except one had a history of seasonal allergies. All four were taking proton pump inhibitor before and after RFA. Two patients with EE drank alcohol, one of which was a smoker. EE is a potential adverse event of RFA for BE. The absence of esophageal dysfunction symptoms suggests a different clinicopathological entity from eosinophilic esophagitis. Further studies should be done to assess its clinical significance, if therapy is needed, or if it may eventually lead to eosinophilic esophagitis.

Investigating the role of X chromosome breakpoints in premature ovarian failure

The importance of the genetic factor in the aetiology of premature ovarian failure (POF) is emphasized by the high percentage of familial cases and X chromosome abnormalities account for 10% of chromosomal aberrations. In this study, we report the detailed analysis of 4 chromosomal abnormalities involving the X chromosome and associated with POF that were detected during a screening of 269 affected women. Conventional and molecular cytogenetics were valuable tools for locating the breakpoint regions and thus the following karyotypes were defined: 46,X,der(X)t(X;19)(p21.1;q13.42)mat, 46,X,t(X;2)(q21.33;q14.3)dn, 46,X,der(X)t(X;Y)(q26.2;q11.223)mat and 46,X,t(X;13)(q13.3;q31)dn. A bioinformatic analysis of the breakpoint regions identified putative candidate genes for ovarian failure near the breakpoint regions on the X chromosome or on autosomes that were involved in the translocation event. HS6ST1, HS6ST2 and MATER genes were identified and their functions and a literature review revealed an interesting connection to the POF phenotype. Moreover, the 19q13.32 locus is associated with the age of onset of the natural menopause. These results support the position effect of the breakpoint on flanking genes, and cytogenetic techniques, in combination with bioinformatic analysis, may help to improve what is known about this puzzling disorder and its diagnostic potential.

A de novo supernumerary genomic discontinuous ring chromosome 21 in a child with mild intellectual disability

Small supernumerary marker chromosomes (sSMCs) are structurally abnormal extra chromosomes that cannot be unambiguously identified or characterized by conventional banding techniques alone, and they are generally equal in size or smaller than chromosome 20 of the same metaphase spread. Small supernumerary ring chromosomes (sSRCs), a smaller class of marker chromosomes, comprise about 10% of the cases. For various reasons these marker chromosomes have been the most difficult to characterize; although specific syndromes have not yet been defined, 60% of cases are associated with an abnormal phenotype. The chromosomal material involved, the degree and tissutal distribution of mosaicism, and the possible presence of uniparental disomy, are the important factors determining whether or not the ring chromosome will give rise to symptoms. Using conventional and molecular cytogenetics approaches we identified a de novo chromosome 21 sSRC in a child with speech delay and mild intellectual disability. By using aCGH analysis and SNP arrays, we report the presence of two discontinuous regions of chromosome 21 and the paternal origin of the sSRC. A thorough neuropsychiatric evaluation is also provided. Only few other cases of complex discontinuous ring chromosomes have been described in detail.

Chromosome territories, X;Y translocation and Premature Ovarian Failure: is there a relationship?

BACKGROUND

Premature ovarian failure (POF) is a secondary hypergonadotrophic amenorrhea occurring before the age of 40 and affecting 1-3% of females. Chromosome anomalies account for 6-8% of POF cases, but only few cases are associated with translocations involving X and Y chromosomes.This study shows the cytogenetic and molecular analysis of a POF patient came to our attention as she developed a left ovary choriocarcinoma at the age of 10 and at 14 years of age she presented secondary amenorrhea with elevated levels of gonadotropins.

RESULTS

Breakpoint position on X and Y chromosomes was investigated using Fluorescent In Situ Hybridisation (FISH) with a panel of specific BAC probes, microsatellite analysis and evaluation of copy number changes and loss of heterozigosity by Affymetrix(R) GeneChip platform (Santa Clara, CA, USA). Patient's karyotype resulted 46, X, der(Y)t(X;Y)(q13.1;q11.223). X inactivation study was assessed by RBA banding and showed preferential inactivation of derivative chromosome. The reciprocal spatial disposition of sexual chromosome territories was investigated using whole chromosome painting and centromeres probes: patient's results didn't show a significant difference in comparison to normal controls.

CONCLUSION

The peculiar clinical case come to our attention highlighted the complexity of POF aetiology and of the translocation event, even if our results seem to exclude any effect on nuclear organisation. POF phenotype could be partially explained by skewed X chromosome inactivation that influences gene expression.

De novo balanced chromosome rearrangements in prenatal diagnosis

OBJECTIVE

We surveyed the datasheets of 29 laboratories concerning prenatal diagnosis of de novo apparently balanced chromosome rearrangements to assess the involvement of specific chromosomes, the breakpoints distribution and the impact on the pregnancy outcome.

METHOD

By means of a questionnaire, data on 269.371 analyses performed from 1983 to 2006 on amniotic fluid, chorionic villus and fetal blood samples were collected.

RESULTS

A total of 246 balanced anomalies were detected at frequencies of 72% for reciprocal translocations, 18% for Robertsonian translocations, 7% for inversions and 3% for complex chromosome rearrangements. The total frequencies of balanced rearrangements were 0.09%, 0.08% and 0.05% on amniotic fluid, chorionic villus and fetal blood samples.

CONCLUSION

A preferential involvement of chromosomes 22, 7, 21, 3, 9 and 11 and a less involvement of chromosomes X, 19, 12, 6 and 1 was observed. A nonrandom distribution of the breakpoints across chromosomes was noticed. Association in the location of recurrent breakpoints and fragile sites was observed for chromosomes 11, 7, 10 and 22, while it was not recorded for chromosome 3. The rate of pregnancy termination was about 20%, with frequencies decreasing from complex chromosomal rearrangements (33%), reciprocal translocations (24%) to inversions (11%) and Robertsonian translocations (3%).

Endometrioid-like yolk sac and Sertoli-Leydig cell tumors in a carrier of a Y heterochromatin insertion into 1qh region: a causal association?

We describe the case of a young woman showing yolk sac tumors (YST) and a Sertoli-Leydig cell tumor (SLCT) in the right ovary, with recurrences in the right adnexum and with hepatic metastasis. To our knowledge, YST and SLCT have never been described as components of the same tumor or reported as associated in the same patient. The patient's karyotype showed the presence of Y chromosome inserted into the 1qh region; the inserted region corresponded to Yq12 heterochromatin. LOH analysis revealed 1p36 paternal allele loss in the proband tumor, thus supporting a germ cell origin for the tumor. The presence of Y heterochromatin in 1qh DNA might induce disturbances in the normal regulation of oncogenes located in 1q.

Cytogenetic and molecular evaluation of 241 small supernumerary marker chromosomes: Cooperative study of 19 Italian laboratories

PURPOSE

We evaluated the experiences of 19 Italian laboratories concerning 241 small supernumerary marker chromosomes (sSMCs) with the aim of answering questions arising from their origin from any chromosome, their variable size and genetic content, and their impact on the carrier's phenotype.

METHODS

Conventional protocols were used to set up the cultures and chromosome preparations. Both commercial and homemade probes were used for the fluorescent in situ hybridization analyses.

RESULTS

A total of 113 of the 241 sSMCs were detected antenatally, and 128 were detected postnatally. There were 52 inherited and 172 de novo cases. Abnormal phenotype was present in 137 cases (57%), 38 of which were antenatally diagnosed. A mosaic condition was observed in 87 cases (36%). In terms of morphology, monocentric and dicentric bisatellited marker chromosomes were the most common, followed by monocentric rings and short-arm isochromosomes. The chromosomes generating the sSMCs were acrocentric in 132 cases (69%) and non-acrocentric chromosomes in 60 cases (31%); a neocentromere was hypothesized in three cases involving chromosomes 6, 8, and 15.

CONCLUSION

The presented and published data still do not allow any definite conclusions to be drawn concerning karyotype-phenotype correlations. Only concerted efforts to characterize molecularly the sSMCs associated or not with a clinical phenotype can yield results suitable for addressing karyotype-phenotype correlations in support of genetic counseling.

Severe intrauterine growth restriction and trisomy 15 confined placental mosaicism: a case report and review of literature

OBJECTIVES

To correlate confined placental mosaicism (CPM) for trisomy 15 with severe intrauterine growth restriction (IUGR) and early death after birth (age of 6 months).

METHODS

Chromosome analysis was performed on amniotic fluid at 21st week of gestation, on peripheral blood at birth and on fibroblasts at death using conventional techniques. FISH was performed with Chromoprobe I-Multiprobe System kit and commercial probes according to manufacturer's protocol. DNA was extracted from parental and child peripheral blood, placenta tissue and skin fibroblasts, and UPD tests were done with microsatellites selected from Genome Data Base.

RESULTS

The child presented severe hypospadias, micropenis, bilateral cryptorchidism and bifid scrotum, inguinal hernia, dolichomegacolon, severe thymic lymphatic depletion and heart hypertrophy, mainly involving right ventricle. Mosaic trisomy 15 (84%) was discovered by FISH on placental biopsy at term. Uniparental disomy (UPD) for chromosome 15 was excluded. Prenatal (amniotic fluid), postnatal (peripheral blood) karyotypes and analysis on skin fibroblast metaphases were normal. Since the autopsy showed some features suggesting genetic syndromes, such as CATCH22, Williams-Beuren syndrome, matUPD2, we excluded the presence of all these diseases.

CONCLUSIONS

The only explanation for this clinical case seems to be the presence of tris15CPM that is reported as one of IUGR causes.

Role of FISH on Uncultured Amniocytes for the Diagnosis of Aneuploidies in the Presence of Fetal Anomalies

OBJECTIVE

To assess the accuracy of fluorescent in situ hybridization (FISH) on amniocytes in fetuses affected by structural malformations suggestive of chromosomal anomalies.

METHODS

FISH of uncultured amniotic fluid cells and conventional cytogenetic analysis were performed on 48 pregnancies with ultrasonographic (US) evidence of fetal anomalies. The AneuVysion assay (Vysis) with specific probes for chromosomes 13, 18, 21, X and Y, was used. Amniotic fluid samples were obtained between the 14th and 34th weeks of gestation.

RESULTS

In cases with a single abnormal US finding (n = 15), 5 aneuploidies were detected (1 case of trisomy 13 and 4 of trisomy 21). In the group with two or more malformations (n = 33) there were 15 aneuploidies (9 cases of trisomy 18, 2 of trisomy 21, 2 monosomy X, 1 trisomy 13, and 1 triploidy). In this group, conventional cytogenetic analysis revealed two additional chromosomal anomalies not detectable by FISH (1 trisomy 16 mosaic, and a terminal deletion 4p). No sex aneuploidies were observed.

CONCLUSIONS

The lack of false-positive diagnosis in the FISH analysis in our sample prompts us to consider interphase FISH as a useful tool in pregnancies at high risk for chromosomal aneuploidies. When FISH analysis is normal, the overall risk of chromosomal abnormalities is significantly reduced. However, the finding of two chromosomal anomalies undetectable by AneuVysion assay confirms the need for conventional chromosome analysis to complement FISH results. Moreover, the results collected here, in agreement with those already reported in the literature, indicate that FISH analysis on uncultured amniocytes can play an important role in counselling and decision-making, especially in cases at risk for aneuploidies, such as those with structural abnormalities at US.

Nonhomologous Robertsonian translocations(NHRTs) and uniparental disomy(UPD) risk: an Italian multicentric prenatal survey

OBJECTIVES

The risk of uniparental disomy (UPD) occurrence associated with the prenatal finding of balanced nonhomologous Robertsonian translocations (NHRTs) has been estimated only on limited empirical data. The aim of the study was to verify the estimate of the general risk, to get narrower confidence intervals by cumulating the data and to obtain risk estimates for specific translocation types.

METHODS

We tested for UPD 160 prenatal specimens referred to the participant centers after the cytogenetic finding of NHRT.

RESULTS

One case of upd(14)mat was found, associated with a 45,XX,der(14;22)mat fetal karyotype. The general empirical risk of UPD occurrence in NHRT carrier fetuses, corrected for the actual number of chromosomes analyzed, was 0.76% (95% CI 0.02-4.25%). Cumulative data with previous studies gives a general risk of UPD associated with NHRT of 0.80% (95% CI 0.17-2.34%). The UPD risk for the specific NHRT der(13;14) did not significantly differ from that of the other NHRTs taken together.

CONCLUSION

The present survey confirms the previously estimated risk of occurrence of UPD in offspring of NHRT carriers as a low, but not negligible risk, worth being investigated in prenatal diagnosis.

Supernumerary ring chromosome 8: Clinical and molecular cytogenetic characterization in a case report

We report on a 3-year-old male with developmental delay, autistic behavior, and minor abnormalities consistent with trisomy 8 syndrome whose cytogenetic analysis revealed mosaicism for a supernumerary ring chromosome (SRC). Fluorescence in situ hybridization (FISH) studies, using centromeric and yeast artificial chromosome (YAC) probes, were performed to characterize further the supernumerary chromosome. The ring origin has been detected from the short arm of chromosome 8, resulting in r(8)(p10p23.1). Moreover, uniparental disomy (UPD) using microsatellite analysis was excluded. To our knowledge a total of 25 cases, confirmed by FISH, have been reported with either supernumerary marker or ring chromosome 8. We present a detailed clinical and molecular cytogenetic characterization of this additional case in order to better define the genotype-phenotype correlation.

Identification of a small supernumerary marker chromosome, r(2)(p10q11.2), and the problem of determining prognosis

The identification of small supernumerary marker chromosomes (SMCs) and the elucidation of their clinical significance remain two of the problems in classical human cytogenetics. We observed a small supernumerary ring in amniotic fluid cell cultures and identified its origin as r(2)(p10q11.2) and its extent by means of fluorescent in situ hybridisation (FISH). Uniparental disomy (UPD) was excluded by microsatellite analysis using polymorphic markers localised in the same region. On the basis of normal ultrasonographic checks, the patient decided to continue the pregnancy. A normal female was delivered at term and subsequent neonatal follow-ups confirmed the normal phenotype and development. In the present case, genetic counselling was not helpful because of the absence of reference cases. Detailed characterisation made it possible to correlate the normal baby phenotype with the trisomic 2p10-2q11.2 genomic region. Further molecular cytogenetic investigations of SMCs classified by DNA content and pregnancy outcome data should improve genetic counselling and risk evaluation.

Vascular expression of Notch pathway receptors and ligands is restricted to arterial vessels

Mice with targeted mutations in genes required for Notch signal transduction die during embryogenesis, displaying overt signs of hemorrhage due to defects in their vascular development. Surprisingly, directed expression of a constitutively active form of Notch4 within mouse endothelial cells produces a similar vascular embryonic lethality. Moreover, patients with mutations in Notch3 exhibit the cerebral vascular disorder, cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). These findings underscore the importance of Notch signaling in vascular development; however, they do not identify the specific functional defect. Here, we report that Notch1, Notch3, Notch4, Delta4, Jagged1 and Jagged2 are all expressed in arteries, but are not expressed by veins. These findings identify an aspect of Notch signaling that could contribute to the mechanism by which this pathway modulates vascular morphogenesis.

Molecular definition of Xq common-deleted region in patients affected by premature ovarian failure

High-resolution cytogenetic analysis of a large number of women with premature ovarian failure (POF) identified six patients carrying different Xq chromosome rearrangements. The patients (one familial and five sporadic cases) were negative for Turner's stigmata and experienced a variable onset of menopause. Microsatellite analysis and fluorescent in situ hybridization (FISH) were used to define the origin and precise extension of the Xq anomalies. All of the patients had a Xq chromosome deletion as the common chromosomal abnormality, which was the only event in three cases and was associated with partial Xp or 9p trisomies in the remaining three. Two of the Xq chromosome deletions were terminal with breakpoints at Xq26.2 and Xq21.2, and one interstitial with breakpoints at Xq23 and Xq28. In all three cases, the del(X)s retained Xp and Xq specific telomeric sequences. One patient carries a psu dic(X) with the deletion at Xq22.2 or Xq22.3; the other two [carrying (X;X) and (X;9) unbalanced translocations, respectively] showed terminal deletions with the breakpoint at Xq22 within the DIAPH2 gene. Furthermore, the rearranged X chromosomes were almost totally inactivated, and the extent of the Xq deletions did not correlate with the timing of POF. In agreement with previous results, these findings suggest that the deletion of a restricted Xq region may be responsible for the POF phenotype. Our analysis indicates that this region extends from approximately Xq26.2 (between markers DXS8074 and HIGMI) to Xq28 (between markers DXS 1113 and ALD) and covers approximately 22 Mb of DNA. These data may provide a starting point for the identification of the gene(s) responsible for ovarian development and folliculogenesis.

Hepatitis B vaccination program at a New York City hospital: seroprevalence, seroconversion, and declination

BACKGROUND

Despite implementation of hepatitis B vaccination programs, 2 problems have prevented full vaccine-induced protection of health care workers (HCWs). About 10% to 12% of vaccinated HCWs do not develop antibody, and many HCWs continue to decline vaccination. To determine the effectiveness of our hepatitis B vaccine program, we studied rates of postvaccination seroconversion and vaccine declination.

METHODS

Employee health service records were used to determine demographic features, hepatitis B surface antibody serostatus at baseline, serologic response to vaccine, and declination or acceptance of vaccine.

RESULTS

About 26% of HCWs were seropositive at baseline, including those vaccinated before employment. Higher seroprevalence rates were seen among those born outside the United States, nurses, and laboratory workers. Seroconversion occurred in only 79% of HCWs who completed a 3-vaccine series. Increasing age was the only significant risk for failure to convert. Declination rates overall were about 45% and were lowest in HCWs who have jobs that included potential exposure to blood.

CONCLUSION

Hepatitis B seroprevalence among HCWs at our hospital is higher than in many other urban hospitals in the United States; over postvaccination seroconversion rate is substantially lower; and our declination rate of 45% resembles other published series. Declination of vaccine and failure to respond to vaccine continue to thwart achievement of full control of this preventable occupational infection.

Carbon monoxide contributes to the cytokine-induced inhibition of surfactant synthesis by human type II pneumocytes

BACKGROUND

An increase in cyclic guanosine 3',5'-monophosphate (cGMP) due to nitric oxide generation is known to participate in the mediation of the tumor necrosis factor alpha (TNF-alpha) effect in type II cells. Because guanylyl cyclase can be activated also by carbon monoxide (CO), in this study we examined the ability of human type II pneumocytes to produce CO in the presence of cytokines and the relative contribution of this molecule to the TNF-alpha and interleukin 1 effects.

DESIGN

Type II pneumocytes were isolated from cadaveric multiple-organ donors by enzymatic digestion, adherence separation of macrophages, and gradient purification. After preculture for 24 hours, cells were cultured for 24 hours in the presence or absence of TNF-alpha, interleukin 1, sodium nitroprusside, N(omega)-nitro-1-arginine, CO, hemin, zinc-protoporphyrin type IX, deferoxamine mesylate, S-adenosyl-L-methionine, alpha-tocopherol, methylene blue (a guanylyl cyclase inhibitor), 8-bromine-cGMP, and combinations of these reagents. Both CO (picomole per microgram of protein) and nitric oxide release to the medium and the cGMP (picomole per microgram of protein) content of the cells were measured. In a different set of experiments, D-glucose labeled with radioactive carbon (14C) was added to the medium, and the labeling of several lipid fractions was determined (picomole per microgram of protein).

RESULTS

D-[14C]glucose incorporation into phosphatidylcholine, the main surfactant component, was selectively inhibited in the presence of cytokines, CO, sodium nitroprusside, or 8-bromine-cGMP. The inhibitory effect of TNF-alpha was partially reversed by N(omega)-nitro-L-arginine, deferoxamine, or alpha-tocopherol and totally reversed by methylene blue. Tumor necrosis factor alpha induced an increase in cGMP cell content and in the CO and nitric oxide release to the medium. Hemin increased CO and cGMP production and decreased phosphatidylcholine synthesis. Zinc-protoporphyrin type IX, an inhibitor of heme oxygenase, and all 3 antioxidants, which inhibited CO production, also antagonized the TNF-alpha effect on cGMP and phosphatidylcholine synthesis.

CONCLUSIONS

Intracellular cGMP increase due to an endogenous generation of both CO and nitric oxide mediates the cytokine-induced inhibition of surfactant synthesis by type II pneumocytes. Both lipid peroxidation and heme oxygenase activity are sources for the observed CO production.

Expression of three rare fragile sites: chromosomal truncation, amplification of distal segment and telomeric renewal

Fluorescence in situ hybridization with a telomeric probe was used to monitor telomeric renewal following breakage induced by the rare fragile sites FRA10A, FRA12A and FRA16B. Interstitial telomere-like sequences were detected only at the break sites of FRA10A.

Risk of tuberculin conversion according to occupation among health care workers at a New York City hospital

Concern about the risk to health care workers of occupationally acquired tuberculosis has resulted in extensive and frequently revised guidelines from the Centers for Disease Control and Prevention (CDC). Most recent studies, however, have determined that community, rather than occupational, exposure is the more significant risk for tuberculin conversion. To assess the relative contribution of community versus occupational risk, we reviewed the health records of 1,303 persons employed from 1991 to 1994 at St. Clare's Hospital in New York City, a hospital with a high tuberculosis case-rate. Demographic information included age, gender, postal zone of residence, country of birth, and BCG vaccination status, while occupations were placed into one of five groups. In multivariate analysis, occupation was significantly associated with risk of tuberculin conversion, while postal zone of residence was not. The group that included housekeeping, laundry, and security personnel and the physician-nurse group had the highest conversion rates. After implementation of CDC guidelines, there was a significant improvement in the employee tuberculin conversion rate. At our hospital, occupation was strongly associated with risk of tuberculin conversion.

Benefit of two-step PPD testing of new employees at a New York City hospital

BACKGROUND

Recent concern about nosocomial transmission of tuberculosis has led hospitals to scrutinize employee tuberculin conversion rates. The Centers for Disease Control and Prevention recommends two-step testing of new employees to limit the booster phenomenon. The cost of such a program and its subsequent yield have not recently been examined.

METHODS

Employee health records were retrospectively reviewed of persons hired from 1993 and 1994 at St. Clare's Hospital in New York City, all of whom received two-step testing at time of initial employment.

RESULTS

Of 262 new employees, 107 (41%) had positive tuberculin results on initial testing. The results of 15 (9.7%) of the remaining 155 patients became positive on two-step testing administered 1 week later. Persons with a positive second test result were significantly more likely to be male or foreign born or to have received previous bacille Calmette-Guérin vaccination. Identification of these 15 persons and exclusion of them from probable subsequent conversion prevented an almost 50% increase in the annual conversion rate at our hospital, from 3.2% to 4.7%.

CONCLUSION

Two-step tuberculin testing is an essential means of identifying persons with a baseline positive tuberculin test result, thus allowing accurate reporting of subsequent employee tuberculin conversions.

S-adenosylmethionine protects hepatocytes against the effects of cytokines

Cytokines are thought to play an important role in the hepatocellular dysfunction that occurs during sepsis. Some cytokines have been shown to increase lipogenesis and to induce toxicity in isolated hepatocytes. Oxygen free radicals have been implicated as mediators of some cytokine effects. In this study we investigate a possible protection action of S-adenosyl-L-methionine against the toxic effects of cytokines on isolated hepatocytes. Isolated rat hepatocytes were precultured for 24 hr and then cultured for 1, 2, 3, 6, 12, or 24 hr in the presence or absence of S-adenosyl-L-methionine (12 micromol/l0) and/or either tumor necrosis factor (100, 200, or 500 ng/ml) or interleukin-1 (30, 60, or 120 IU/ml). Lactate dehydrogenase (media), and malondialdehyde, reduced glutathione, and the incorporation of D-[U- 14 C] glucose into different lipid fractions (cells) were determined. Both cytokines significantly increased hepatocyte malondialdehyde content, lactate dehydrogenase release, and triacylglycerol synthesis. None of these effects were observed in the presence of S-adenosyl--L-methionine. In addition, S-adenosyl-L-methionine was able to attenuate the decrease in phosphatidylcholine labeling also induced by both cytokines, and to prevent the increase in free fatty acid synthesis induced by tumor necrosis factor. Incubation in the presence of S-adenosyl-L-methionine also increased hepatocyte glutathione content (7.1 +/- 0.7, after 24 hr, vs 3.6 +/- 0.3 nmole/mg protein, P < 0.01), and prevented the decrease in glutathione induced by tumor necrosis factor (5.4 +/- 0.2 vs 2.1 +/- 0.1 nmole/mg protein, 100 ng/ml TNF alpha at 24 hr, P < 0.01). Our results show that S-adenosyl-L-methionine has a protective effect on hepatocytes against the in vitro effect of cytokines.

Evidence for a cyclic guanosine monophosphate-dependent, carbon monoxide-mediated, signaling system in the regulation of TNF-alpha production by human pulmonary macrophages

BACKGROUND AND OBJECTIVES

The second messenger cyclic guanosine 3',5'-monophosphate (cGMP) seems to be implicated in the release of tumor necrosis factor alpha (TNF-alpha) by activated macrophages. There is controversy regarding the potential of human macrophages to produce nitric oxide (NO). Since guanylate cyclase can be activated also by carbon monoxide (CO) and this gas may be formed endogenously, we examined the ability of human pulmonary macrophages to produce CO in the presence of lipopolysaccharide (LPS) or LPS+interferon gamma (IFN-gamma). In addition, the source and the relative contribution of this molecule to the LPS-induced increase in cell cGMP content and TNF-alpha release were explored.

DESIGN

Interstitial macrophages were obtained from multiple organ donor lungs by enzymatic digestion. After 24-hour preculture, purified macrophages were cultured for 24 hours in the presence or absence of LPS, LPS+IFN-gamma, CO (250 and 500 mumol/L), sodium nitroprusside, 8-Br-cGMP, hemoglobin, methylene blue, zinc-protoporphyrin IX, hemin, S-adenosylmethionine, deferoxamine mesylate, or combinations. The cGMP content of the cells and TNF-alpha, CO, and NO release to the medium were determined.

RESULTS

In the presence of LPS, TNF-alpha production was not accompanied by any detectable increase in the NO release to the medium. However, an increase in medium CO concentration (mean +/- SEM) (5.81 +/- 0.20 vs 3.74 +/- 0.08 pmol/microgram protein; n = 11; P < .01) and cell cGMP content (0.273 +/- 0.021 vs 0.138 +/- 0.019 pmol/microgram protein; n = 10; P < .01) was observed. These changes were more pronounced in the presence of LPS+IFN-gamma. Release of TNF-alpha also was induced by both sodium nitroprusside and 8-Br-cGMP. In contrast, methylene blue, a guanylate cyclase inhibitor, inhibited LPS-, LPS+IFN-gamma-, and sodium nitroprusside-induced TNF-alpha production and cGMP increase; hemoglobin, which traps CO, had a similar effect.

CONCLUSION

Intracellular cGMP increase, secondary to an endogenous production of CO, participates in the release of TNF-alpha by activated human pulmonary macrophages.

Beneficial effect of S-adenosylmethionine during both cold storage and cryopreservation of isolated hepatocytes

Oxygen free radicals appear to be the prime cell-toxic products during cold preservation. Glutathione (GSH) seems to play a critical role in cell protection against oxidant stress. The experimental decrease of intracellular GSH in vivo may be prevented by the administration of S-adenosylmethionine (SAMe), which seems also to play an important role in preserving the structure of cell membranes. We designed our study to investigate whether the addition of SAMe to EuroCollins solution (EC) could provide a similar degree of protection as the more complex University of Wisconsin (UW) solution during cold preservation. In addition, we have investigated a possible protective action of SAMe during hepatocyte cryopreservation. Wistar rat hepatocytes (10(6) cells/ml) were stored in either EC (+/- 12 mumol/l SAMe) or UW. In parallel, hepatocytes (10(6) cells/ml) were cryopreserved in M199 culture medium (+/- SAMe) using dimethyl sulfoxide as cryoprotectant. LDH release, viability, and hepatocyte GSH and malondialdehyde (MDA) content were sequentially determined during cold preservation. There were no differences on viability or GSH and MDA content between EC+SAMe and UW stored cells, although LDH release was slightly higher in the first group. The addition of SAMe also attenuated the decrease in both viability (37 +/- 0.8 vs 53.0 +/- 7.4%, mean +/- SEM, N = 5, P < 0.05) and GSH content (13.4 +/- 15.1 vs 45.1 +/- 16.8%, mean +/- SEM, N = 5, P < 0.01), observed after thawing. Our results suggest that SAMe could be a useful additive for both cold storage and cryopreservation solutions of hepatocytes.

Prevalence of PPD positivity among new employees at a hospital in New York City

OBJECTIVE

To determine the prevalence of tuberculin reactivity among all new employees at a hospital in New York City.

DESIGNS

Prospective measurement of purified protein derivative (PPD) status in consecutive new employees at a hospital in New York City from 1991 to 1993. All employees are tested as part of a preemployment physical, assuring complete compliance. Aplisol (Parke-Davis, Morris Plains, NJ) was used in 1991 and 1992, and Tubersol (Connaught, Swiftwater, PA) in 1993. Tests were applied and interpreted by trained employee health personnel.

RESULTS

Of 313 consecutive new employees, comprising all job categories, 40% were PPD positive at time of initial hire, including 20% of US-born and 70% of foreign-born employees. Of 114 persons who had received BCG vaccination, 67% were PPD positive. By multivariate regression analysis, age, BCG vaccination history, and foreign country of birth were independent predictors of a reactive PPD test.

CONCLUSIONS

The high prevalence of tuberculin reactivity may reflect high rates of Mycobacterium tuberculosis infection and disease in the community, complicating interpretation of the efficacy of Centers for Disease Control and Prevention (CDC) guidelines to prevent the spread of tuberculosis in healthcare facilities.

Antiulcer action and toxicity of Styrax camporum and Caesalpinia ferrea

Oral administration of Styrax camporum Pohl and Caesalpinia ferrea Martius stem extracts, atropine, and cimetidine, during 15 days, decreased the ulceration size, gastric secretion volume, and increased collagen fibre number of chronic ulcer induced by acetic acid in rats. The pH increased and the concentration of hydrochloric acid decreased after administration of atropine and cimetidine. The ethyl acetate fraction, obtained by chromatography from Styrax camporum Pohl extracts, showed antiulcer activity. The subchronic toxicity was studied during 30 days, through weight variation, water and food consumption and spleen, lung, kidney and liver relative weights. No difference to the control-lot was observed.