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1.
Dis Aquat Organ ; 137(2): 131-144, 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31854331

RESUMO

Steller sea lions (SSLs) Eumetopias jubatus experienced a population decline in the 1960s, leading to the listing of the western stock as endangered and the eastern stock as threatened under the US Endangered Species Act. A decrease of births in the western stock beginning in the late 1960s indicates that reproductive failure may have contributed to the decline. We evaluated the role pathogens play in spontaneous abortions, premature births and neonatal deaths in SSLs. Archived tissues from carcasses (n = 19) collected in Alaska from 2002 to 2015 were tested by PCR for Coxiella burnetii, Brucella spp., Chlamydia and morbilliviruses. Animals examined included 47% premature pups, 32% aborted fetuses, 11% neonates and 11% intrauterine fetuses. Gross necropsy and histology findings were summarized in the context of the PCR findings. Tissues were negative for Chlamydia and C. burnetii. Brucella spp. were detected in the lung tissues of 3 animals, including 1 positive for the ST27 strain, the first detection of Brucella spp. DNA in SSLs. Phocine distemper virus was detected in 3 animals in 2 skin lesions and 1 placenta by hemi-nested diagnostic qRT-PCR. Both skin and the placental lesions had vesiculoulcerative changes, and 1 skin lesion contained inclusion bodies in syncytia and upon histologic examination, suggesting that the lesions may be associated with an infection reminiscent of phocine distemper virus, the first in SSLs. We highlight the continuing need for disease surveillance programs to improve our understanding of the prevalence and potential population impacts of these infectious disease agents for pinnipeds in Alaskan waters.


Assuntos
Coxiella burnetii , Leões-Marinhos , Alaska , Animais , Espécies em Perigo de Extinção , Feminino , Gravidez , Inquéritos e Questionários
2.
J Food Drug Anal ; 23(3): 486-492, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28911707

RESUMO

The objective of this study was to determine the concentrations of heavy metals in bagged and leaf black teas of the same brand and evaluate the percentage transfer of metals to tea infusion to assess the consumer exposure. Ten leaf black teas and 10 bagged black teas of the same brand available in Poland were analyzed for Zn, Mn, Cd, Pb, Ni, Co, Cr, Al, and Fe concentrations both in dry material and their infusion. The bagged teas contained higher amounts of Pb, Mn, Fe, Ni, Al, and Cr compared with leaf teas of the same brand, whereas the infusions of bagged tea contained higher levels of Mn, Ni, Al, and Cr compared with leaf tea infusions. Generally, the most abundant trace metals in both types of tea were Al and Mn. There was a wide variation in percentage transfer of elements from the dry tea materials to the infusions. The solubility of Ni and Mn was the highest, whereas Fe was insoluble and only a small portion of this metal content may leach into infusion. With respect to the acceptable daily intake of metals, the infusions of both bagged and leaf teas analyzed were found to be safe for human consumption.

3.
Ned Tijdschr Geneeskd ; 157(33): A5547, 2013.
Artigo em Holandês | MEDLINE | ID: mdl-23945430

RESUMO

The reform of the system in 2006 aimed at reducing waiting lists in an efficient manner. Performance-linked funding and regulated competition did indeed lead to improved efficiency. The other side of the coin is overtreatment, and expensive and not infrequently damaging growth in volume. In order to control costs, three strategies have been determined: agreements with an annual cap on volume; (b) collaboration of regional health-care providers with the mission of improving results in health care (with profit-sharing if costs fall); and (c) fusions reducing the number of hospitals which reduces the burden of injuries (supply no longer creates its own demand). This article comments on these strategies. The author argues for a fourth approach: if the quality of health care improves, the number of complications will fall, overtreatment will decline and the outcome will be a decrease in burden of injuries. This requires the health care insurers to modify the way they manage their contracts and methods of payment, and stimulates competition based on quality.


Assuntos
Eficiência Organizacional , Administração Hospitalar/normas , Qualidade da Assistência à Saúde , Listas de Espera , Custos de Cuidados de Saúde , Custos Hospitalares , Humanos , Países Baixos
4.
Atherosclerosis ; 228(2): 339-45, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23582588

RESUMO

PURPOSE: The aim of this study was to compare the ability of (18)F-FDG PET and iron contrast-enhanced MRI with a novel USPIO (P904) to assess change in plaque inflammation induced by atorvastatin and dietary change in a rabbit model of atherosclerosis using a combined PET/MR scanner. MATERIALS AND METHODS: Atherosclerotic rabbits underwent USPIO-enhanced MRI and (18)F-FDG PET in PET/MR hybrid system at baseline and were then randomly divided into a progression group (high cholesterol diet) and a regression group (chow diet and atorvastatin). Each group was scanned again 6 months after baseline imaging. R2* (i.e. 1/T2*) values were calculated pre/post P904 injection. (18)F-FDG PET data were analyzed by averaging the mean Standard Uptake Value (SUVmean) over the abdominal aorta. The in vivo imaging was then correlated with matched histological sections stained for macrophages. RESULTS: (18)F-FDG PET showed strong FDG uptake in the abdominal aorta and P904 injection revealed an increase in R2* values in the aortic wall at baseline. At 6 months, SUVmean values measured in the regression group showed a significant decrease from baseline (p = 0.015). In comparison, progression group values remained constant (p = 0.681). R2* values showed a similar decreasing trend in the regression group suggesting less USPIO uptake in the aortic wall. Correlations between SUVmean or Change in R2* value and macrophages density (RAM-11 staining) were good (R(2) = 0.778 and 0.707 respectively). CONCLUSION: This experimental study confirms the possibility to combine two functional imaging modalities to assess changes in the inflammation of atherosclerotic plaques. (18)F-FDG-PET seems to be more sensitive than USPIO P904 to detect early changes in plaque inflammation.


Assuntos
Aorta Abdominal , Doenças da Aorta/diagnóstico , Aterosclerose/diagnóstico , Meios de Contraste , Dextranos , Fluordesoxiglucose F18 , Inflamação/diagnóstico , Imageamento por Ressonância Magnética , Nanopartículas de Magnetita , Placa Aterosclerótica , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Animais , Aorta Abdominal/diagnóstico por imagem , Aorta Abdominal/efeitos dos fármacos , Aorta Abdominal/patologia , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/tratamento farmacológico , Doenças da Aorta/patologia , Aterosclerose/diagnóstico por imagem , Aterosclerose/tratamento farmacológico , Aterosclerose/patologia , Atorvastatina , Modelos Animais de Doenças , Progressão da Doença , Ácidos Heptanoicos/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inflamação/diagnóstico por imagem , Inflamação/tratamento farmacológico , Inflamação/patologia , Valor Preditivo dos Testes , Pirróis/farmacologia , Coelhos , Radiografia , Fatores de Tempo
5.
Horm Metab Res ; 36(6): 406-10, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15241732

RESUMO

In vitro, the growth inhibiting effect of ACTH on adrenocortical cells is well documented, even though there are reports of opposite effects under defined cell culture conditions. In vivo, activation of the ACTH receptor (ACTHR) has a trophic effect on the adrenal cortex, while the effects on proliferation are still under discussion, especially since other POMC derived peptides have been characterized. However, ACTH is thought to act as a differentiation factor with inhibiting effects on tumor growth. In undifferentiated adrenocortical carcinomas, ACTHR expression is frequently lost, which is associated with extensive tumor growth. We describe a new microsatellite marker within the intron of the ACTHR gene termed ACTHRint1. In a series of 114 patients with various adrenal and non-adrenal tumors, the rate of heterozygosity was 100 %. Only one out of 57 patients with adrenocortical adenoma showed LOH at the ACTHR locus, whereas 4 of 10 carcinomas had loss of one allele. Patients suffering from tumors with LOH showed a more aggressive disease course and had earlier recurrences with poor prognosis. These data confirm earlier findings that adrenocortical carcinomas frequently show loss of ACTHR expression, which is associated with a more aggressive tumor growth. However, whether the ACTHR is directly involved in tumor growth or acts a marker of differentiation that is lost in more advanced tumor stages is still not clear.


Assuntos
Neoplasias das Glândulas Suprarrenais/genética , Biomarcadores Tumorais , Carcinoma/genética , Íntrons/genética , Perda de Heterozigosidade/genética , Repetições de Microssatélites/genética , Receptores da Corticotropina/genética , Córtex Suprarrenal/fisiopatologia , Neoplasias das Glândulas Suprarrenais/fisiopatologia , Hormônio Adrenocorticotrópico/metabolismo , Alelos , Carcinoma/fisiopatologia , Humanos , Prognóstico
6.
Br J Soc Psychol ; 40(Pt 2): 159-72, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11446222

RESUMO

It is argued that the differentiation between nationalism and patriotism proposed in the literature can be seen as analogous to judgments based on different types of comparisons: intergroup comparisons with other nations are associated with intergroup behaviour that corresponds to nationalism, whereas temporal or standard comparisons are linked with behaviour that corresponds to patriotism. Four studies (N = 103, 107, 96 and 105) conducted in Germany and Britain examined the hypothesis that national identification and in-group evaluation only show a reliable relationship with out-group rejection under an intergroup comparison orientation. Participants were primed with either an intergroup comparison, a temporal comparison or no explicit comparison orientation. A subsequent questionnaire assessed in-group (own country) identification, in-group evaluation (i.e. national pride) and rejection of national out-groups. Across all four studies, both in-group identification and in-group evaluation show a stronger correlation with out-group derogation if participants were primed with an intergroup comparison orientation compared to temporal and control conditions. Results are discussed with regard to nationalism and patriotism as well as Hinkle and Brown's (1990) model on relational vs. autonomous orientations.


Assuntos
Etnicidade , Rejeição em Psicologia , Identificação Social , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Percepção Social , Inquéritos e Questionários
8.
Eur J Endocrinol ; 144(3): 199-206, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11248736

RESUMO

The regulation of the ACTH-receptor gene is unique in that it is up-regulated by its own ligand, ACTH. Ligand-induced up-regulation of ACTH-receptor expression may be an important adaptive process directed towards optimizing adrenal responsiveness to ACTH in the context of physiological stress and the maintenance of metabolic homeostasis in which the adrenals play a pivotal role. Whereas enhancement by ligand-induced up-regulation permits a more efficient and rapid glucocorticoid response, negative feedback regulation of glucocorticoids in the hypothalamus and pituitary inhibits ACTH secretion and allows a balanced adrenal response to stress. Since the cloning of the promoter region of the ACTH receptor, considerable progress in the understanding of the regulatory processes has been made. The effects of ACTH on ACTH-receptor expression is dependent on cAMP, probably mediated through AP-1. The profound effect of three SF-1-binding sites in the ACTH-receptor promoter was demonstrated by deletion experiments. Conversely, ACTH-receptor expression can be suppressed by adrenal-specific transcription factors,like DAX-1. Despite an extensive search, no activating ACTH-receptor mutations have been found in adrenal tumors,excluding the ACTH receptor as a relevant oncogene in adrenal tumorigenesis. However, the ACTH receptor may act as a differentiation factor as suggested by LOH in adrenal carcinomas with an undifferentiated tumor type. In benign adrenal tumors, a strong correlation between ACTH-receptor expression and expression of P450 steroidogenic enzymes is evident. This close regulative relationship is lost in adrenal carcinoma, probably as a result of tumor dedifferentiation. Down-regulation of ACTH-receptor expression in normal and neoplastic tissue can be achieved by adrenostatic compounds such as aminoglutethimide and metyrapone.


Assuntos
Neoplasias do Córtex Suprarrenal/metabolismo , Neoplasias do Córtex Suprarrenal/patologia , Regulação da Expressão Gênica , Receptores da Corticotropina/metabolismo , Neoplasias do Córtex Suprarrenal/genética , Animais , Éxons/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Íntrons/genética , Perda de Heterozigosidade , Mutação Puntual/genética , Regiões Promotoras Genéticas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores da Corticotropina/genética
9.
AJR Am J Roentgenol ; 174(6): 1759-64, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10845519

RESUMO

OBJECTIVE: We postulated that the pneumothorax rate of transthoracic needle biopsy might improve with an ipsilateral dependent position of the affected side. We tried to determine the feasibility, effectiveness, and safety of CT-guided biopsy with the patient in this position. SUBJECTS AND METHODS: CT-guided needle biopsy with the patient in an ipsilateral dependent position was performed in 23 patients with 17 lung lesions (15 posterior and two anterior) and six mediastinal lesions. Fine-needle aspiration was used in all patients, and core biopsy was also used in six patients. The technical difficulty of the procedure was classified into three grades compared with a routine transthoracic needle biopsy as follows: grade I, no more difficult; grade II, somewhat more difficult; and grade III, much more difficult. RESULTS: Adequate samples were obtained in 22 (96%) of 23 patients. A small asymptomatic pneumothorax occurred in two patients (8.7%). Difficulty was rated grades I, II, and III in 18 (78%), two (9%), and three (13%) procedures, respectively. Four of the five grades II and III procedures were biopsies of anterior lesions. Traversing the pleura was avoided in three of six mediastinal masses. CONCLUSION: Transthoracic needle biopsy of selected lung and mediastinal lesions using an ipsilateral dependent position is feasible, effective, and safe. The role of this technique for reducing the rate of pneumothorax as a result of the biopsy requires further investigation.


Assuntos
Biópsia por Agulha/métodos , Pulmão/patologia , Mediastino/patologia , Radiografia Intervencionista , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha/efeitos adversos , Feminino , Humanos , Pulmão/diagnóstico por imagem , Masculino , Mediastino/diagnóstico por imagem , Pessoa de Meia-Idade , Pneumotórax/etiologia , Postura
10.
Proc Natl Acad Sci U S A ; 97(11): 5717-22, 2000 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-10823932

RESUMO

RNA-binding motif (RBM) genes are found on all mammalian Y chromosomes and are implicated in spermatogenesis. Within human germ cells, RBM protein shows a similar nuclear distribution to components of the pre-mRNA splicing machinery. To address the function of RBM, we have used protein-protein interaction assays to test for possible physical interactions between these proteins. We find that RBM protein directly interacts with members of the SR family of splicing factors and, in addition, strongly interacts with itself. We have mapped the protein domains responsible for mediating these interactions and expressed the mouse RBM interaction region as a bacterial fusion protein. This fusion protein can pull-down several functionally active SR protein species from cell extracts. Depletion and add-back experiments indicate that these SR proteins are the only splicing factors bound by RBM which are required for the splicing of a panel of pre-mRNAs. Our results suggest that RBM protein is an evolutionarily conserved mammalian splicing regulator which operates as a germ cell-specific cofactor for more ubiquitously expressed pre-mRNA splicing activators.


Assuntos
Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Núcleo Celular/metabolismo , Células Germinativas/metabolismo , Humanos , Infertilidade Masculina/metabolismo , Masculino , Camundongos , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Ligação Proteica , Estrutura Terciária de Proteína , Precursores de RNA/metabolismo , Splicing de RNA , Proteínas de Ligação a RNA/genética , Proteínas Recombinantes de Fusão/metabolismo , Fatores de Processamento de Serina-Arginina , Especificidade por Substrato , Técnicas do Sistema de Duplo-Híbrido
11.
Eur J Clin Invest ; 30 Suppl 3: 76-82, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11281374

RESUMO

BACKGROUND: Adrenostatic compounds are frequently used in the treatment of patients with Cushing's syndrome and act via direct inhibition of steroidogenic enzymes. However, additional mechanisms may be involved in the blockade of adrenal steroid secretion. We therefore investigated the effects of aminoglutethimide (AG), metyrapone (MTP) and etomidate (ETO) in the human NCI-h295 adrenocortical carcinoma cell line. MATERIALS AND METHODS: Cells were incubated with increasing doses of the adrenostatic compounds. Steroid hormone secretion (cortisol, 17-OH-progesterone, DHEA-S) and cAMP synthesis were determined and Northern blot analysis and cell proliferation experiments were performed. RESULTS: ETO was the most potent adrenostatic compound inhibiting P450c11 hydroxylase at low concentrations (IC50 15 nM), and also blocking P450 side-chain cleavage (scc) enzyme (IC50 400 nM) at higher concentrations. The pattern of enzyme inhibition was similar for MTP with an IC50 of 3-5 microM for P450c11 and 17 microM for P450scc, while AG blocked P450scc with an IC50 of 10 microM. AG significantly suppressed the baseline ACTH-R mRNA expression in a dose-dependent fashion (300 microM AG: 5% +/- 1%; 30 microM AG: 64% +/- 1%; 3 microM AG: 108% +/- 19% compared with control cells: 100% +/- 11%) but increased glucocorticoid receptor mRNA. The reduced ACTH-R mRNA was paralleled by low ACTH-induced cAMP accumulation indicating reduced expression of ACTH-R protein. The simultaneous incubation of hydrocortisone together with AG reversed the inhibitory effect of AG on the ACTH-R expression. AG and ETO inhibited cell proliferation in the NCI-h295 cells, but ETO was much more potent and showed antiproliferative effects at concentrations of 6 microM. The growth inhibition was not reversed by administration of hydrocortisone. CONCLUSIONS: Our data demonstrate that adrenostatic compounds not only act by suppression of steroidogenic enzymes but can also influence both ACTH-R expression and cell proliferation in adrenal cells. As these effects occur in vitro at concentrations that are reached during treatment with these drugs in patients, they are probably also of clinical relevance. Particularly the antiproliferative activity of ETO may be useful in Cushing's syndrome due to adrenocortical cancer. The interaction of steroidogenesis, ACTH-R and glucocorticoid receptor expression as well as cell proliferation provides a new concept of the intra-adrenal response to stress in humans.


Assuntos
Neoplasias do Córtex Suprarrenal/tratamento farmacológico , Glândulas Suprarrenais/efeitos dos fármacos , Aminoglutetimida/farmacologia , Etomidato/farmacologia , Metirapona/farmacologia , Esteroides/biossíntese , Glândulas Suprarrenais/metabolismo , Divisão Celular/efeitos dos fármacos , Enzima de Clivagem da Cadeia Lateral do Colesterol/antagonistas & inibidores , Humanos , Hidrocortisona/metabolismo , RNA Mensageiro/análise , Receptores da Corticotropina/efeitos dos fármacos , Receptores da Corticotropina/genética , Receptores de Glucocorticoides/efeitos dos fármacos , Receptores de Glucocorticoides/genética , Células Tumorais Cultivadas
12.
J Pers Soc Psychol ; 76(2): 229-45, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10074707

RESUMO

Predictions by social identity theory (SIT) and relative deprivation theory (RDT) concerning preferences for strategies to cope with a negative in-group status position were tested. The focus of the present research was a comparison of the theories regarding their differential patterns of prediction. For this purpose, a natural sample within a specific historical situation was investigated: East Germans after the German unification. First, the predictive power of SIT and RDT variables was tested separately. In a second step, a possible integration of the theories was addressed. Combining the SIT variables and RDT variables led to an integrated model indicating a differential pattern of prediction for intergroup strategies. The RDT components explained the collective responses, whereas SIT constructs were related to individual strategies.


Assuntos
Adaptação Psicológica , Carência Cultural , Modelos Psicológicos , Negativismo , Autoimagem , Classe Social , Identificação Social , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Comportamento Competitivo , Feminino , Alemanha Oriental , Humanos , Masculino , Pessoa de Meia-Idade , Política , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Mudança Social , Mobilidade Social
13.
Zentralbl Chir ; 124(12): 1074-8, 1999.
Artigo em Alemão | MEDLINE | ID: mdl-10670091

RESUMO

About 10% of rectal cancers have to be treated by a multivisceral resection. Within a period of 14 years we performed 103 of these operations, 60 for primary cancers, 43 for recurrent cancers with a significant increase in the latter. The total or partial removal of 204 extra-rectal organs allowed for a R0 resection in 67% of cases. 69% were confirmed as being pT4 by histologic examination. In comparison with conventional rectal resection morbidity is higher at 32% while mortality is identical with 4%. A significant benefit (p < 0.05) in terms of survival is found for primary cancers as opposed to recurrences, R0 resections compared to R1 or R2 resections, lymphnode negative compared to lymphnode positive patients and patients who underwent IORT. The number of additionally removed organs did not influence survival. Compared with the natural course even palliative resections carry a survival benefit and allow the treatment of the often devastating specific morbidity of the disease. Despite adjuvant multimodal therapies the high rate of local and distant recurrences after multivisceral resection of the rectum still poses a major problem.


Assuntos
Neoplasias Retais/cirurgia , Procedimentos Cirúrgicos Operatórios/métodos , Colectomia , Neoplasias Colorretais/cirurgia , Feminino , Humanos , Masculino , Prognóstico
15.
Hum Mol Genet ; 4(5): 869-78, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7633447

RESUMO

We have isolated a gene, PKX1, by virtue of its position within the candidate region for chondrodysplasia punctata in Xp22.3. Although data from one patient render it unlikely that PKX1 is the CDPX gene, this gene shows several interesting features. First, PKX1 appears to encode a novel type of human protein kinase that is related to the catalytic subunit of cAMP-dependent protein kinases and has striking homology to the DC2 protein kinase from Drosophila melanogaster. Second, PKX1 is part of a family of at least four genes or pseudogenes, of which three map to the human sex chromosomes. In contrast to all other genes from the X-specific region of Xp22.3, PKX1 has a homologue on Yp rather than Yq. This is intriguing as it indicates that the single pericentric inversion event hypothesized to have occurred during primate evolution is not sufficient to explain the present X/Y-homology pattern of Xp22.3. Third, we have characterized patients with different chromosomal rearrangements in Xp22.3 or Yp and show that a high proportion of these have occurred within the PKX1 locus. This suggests that the PKX1 gene, besides harbouring a previously described hot-spot for illegitimate Xp/Yp-recombination, contains additional sequences predisposing to chromosomal breakage events.


Assuntos
Proteínas Quinases/genética , Cromossomo X , Sequência de Aminoácidos , Animais , Sequência de Bases , Evolução Biológica , Mapeamento Cromossômico , Clonagem Molecular , DNA Complementar/genética , Drosophila melanogaster/genética , Feminino , Expressão Gênica , Rearranjo Gênico , Humanos , Masculino , Dados de Sequência Molecular , Família Multigênica , Recombinação Genética , Homologia de Sequência de Aminoácidos , Cromossomo Y
16.
Hum Genet ; 95(5): 577-80, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7759082

RESUMO

Although the locus for X-linked recessive chondrodysplasia punctata (CDPX1) has been mapped to the region between PABX and DXS31 (the critical region is about 3 Mb long), the precise location within the critical region has not been determined. In this paper, we describe a boy with a 46,Y,der(X)t(X;Y)(p22.3;q11)mat karyotype and review the genotype-phenotype correlations in three male patients with the combination of apparent lack of clinical features of CDPX1 and a partial deletion of the critical region. The results suggest that the region defined by the two BssHII sites at 3180 and 3570 kb from the Xp telomere may be the target region for the CDPX1 locus.


Assuntos
Condrodisplasia Punctata/genética , Mapeamento Cromossômico , Genes Recessivos/genética , Ligação Genética/genética , Cromossomo X , Adolescente , Povo Asiático , Southern Blotting , Deleção Cromossômica , Feminino , Mãos/diagnóstico por imagem , Humanos , Japão , Cariotipagem , Masculino , Radiografia
17.
Genomics ; 26(2): 229-38, 1995 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-7601447

RESUMO

The study of patients with chromosomal rearrangements has led to the mapping of the gene responsible for X-linked recessive chondrodysplasia punctata (CDPX1; MIM 302950) to the distal part of the Xp22.3 region, between the loci PABX and DXS31. To refine this mapping, a yeast artificial chromosome (YAC) contig map spanning this region has been constructed. Together with the YAC contig of the pseudo-autosomal region that we previously established, this map covers the terminal 6 Mb of Xp, with an average density of 1 probe every 100 kb. Newly isolated probes that detect segmental X-Y homologies on Yp and Yq suggest multiple complex rearrangements of the ancestral pseudoautosomal region during evolution. Compilation of the data obtained from the study of individuals carrying various Xp22.3 deletions led us to conclude that the CDPX disease displays incomplete penetrance and, consequently, to refine the localization of CDPX1 to a 600-kb interval immediately adjacent to the pseudoautosomal boundary. This interval, in which 12 probes are ordered, provides the starting point for the isolation of CDPX1.


Assuntos
Condrodisplasia Punctata/genética , Cromossomo X , Sequência de Bases , Mapeamento Cromossômico , Cromossomos Artificiais de Levedura , Análise Mutacional de DNA , Feminino , Genes Recessivos , Marcadores Genéticos , Humanos , Masculino , Dados de Sequência Molecular , Homologia de Sequência do Ácido Nucleico , Cromossomo Y
18.
Hum Mol Genet ; 3(8): 1337-40, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7987311

RESUMO

Most models on crossover and crossover interference have assumed that the intensity of interference depends inversely on the physical distance separating the respective intervals. The possibility, however, also exists that interference depends on genetic rather than on physical distance. As the human pseudoautosomal region (PAR) on Xp/Yp is physically small, yet genetically a hot spot of recombination in male meiosis, studies on the existence of multiple crossover events may be particularly useful in addressing the question of interference. Our results demonstrate for the first time a double crossover during male meiosis in the human PAR on Xp/Yp. The occurrence of a single obligatory recombination event in this region can, therefore, no longer be taken as a dogma. However, double crossover events seem to remain exceptional and, thus, the model originally suggested by Burgoyne remains globally correct. As both recombination events can be localized within a narrow range of physical distance, theories describing interference due to steric hindrance may have to be reconsidered. This finding may, therefore, have general implications for our understanding of the mechanism of positive and negative crossover interference in mammalian genomes and may be interesting especially for linkage mapping where double recombinations in small intervals tend to be considered as genotyping errors.


Assuntos
Troca Genética , Cromossomo X , Cromossomo Y , Sequência de Bases , Mapeamento Cromossômico , Humanos , Masculino , Dados de Sequência Molecular , Linhagem
19.
Hum Genet ; 93(4): 463-6, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8168818

RESUMO

A male patient carrying an interstitial deletion in Xp22.3 and affected by Kallmann syndrome, X-linked ichthyosis and mental retardation, but without chondrodysplasia punctata or short stature, was investigated with molecular probes from the distal Xp22.3 region. By means of a novel probe, M115, from the relevant region, the distal deletion breakpoint was shown to be between 3.18 and 3.57 Mb from Xptel. As the patient is not affected by X-linked recessive chondrodysplasia punctata, the gene for this disease can therefore be located to within an interval of less than one megabase proximal to the pseudoautosomal boundary. If the chondrodysplasia punctata gene is associated with a CpG island, this leaves only two islands at 2760 and 3180 kb from the Xp telomere as the most promising candidate sites for this gene.


Assuntos
Condrodisplasia Punctata/genética , Ligação Genética , Deleção de Sequência , Cromossomo X , Humanos , Ictiose Ligada ao Cromossomo X/genética , Deficiência Intelectual/genética , Síndrome de Kallmann/genética , Masculino
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