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1.
J Eur Acad Dermatol Venereol ; 38(4): 665-672, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38063244

RESUMO

Atopic dermatitis (AD) is a highly prevalent chronic inflammatory skin disease representing a major source of global disability burden. Disease-modifying therapies are showing promise in chronic inflammatory disorders such as rheumatoid arthritis and Crohn's disease with method and timing of initial treatment impacting long-term disease outcomes. Whether disease-modifying therapies, specifically those used as an early interventional approach, impacts disease course and comorbidity development in AD is not well-understood. We reviewed the progress in disease modification strategies, emphasizing early intervention approaches in common (or proto-typical) inflammatory diseases. Although more common in other fields, disease modification approaches are becoming increasingly investigated in dermatology, though studies in AD are lacking. Despite significant limitations in ongoing and completed studies, early data are promising and suggest that both the choice and timing of early intervention approach can affect long-term disease course and comorbidity development. To best improve AD patient outcomes, more research is needed to further explore the impact of early disease-modifying therapies. Future studies should focus on identifying the most effective approaches and extend the early results to a more inclusive set of comorbidities and longer-term outcomes.


Assuntos
Artrite Reumatoide , Doença de Crohn , Dermatite Atópica , Humanos , Dermatite Atópica/terapia , Dermatite Atópica/epidemiologia , Comorbidade , Progressão da Doença
2.
Artigo em Inglês | MEDLINE | ID: mdl-35820991

RESUMO

BACKGROUND: Previous research suggests that mindfulness training (MT) appears effective at improving mental health in young people. MT is proposed to work through improving executive control in affectively laden contexts. However, it is unclear whether MT improves such control in young people. MT appears to mitigate mental health difficulties during periods of stress, but any mitigating effects against COVID-related difficulties remain unexamined. OBJECTIVE: To evaluate whether MT (intervention) versus psychoeducation (Psy-Ed; control), implemented in after-school classes: (1) Improves affective executive control; and/or (2) Mitigates negative mental health impacts from the COVID-19 pandemic. METHODS: A parallel randomised controlled trial (RCT) was conducted (Registration: https://osf.io/d6y9q/; Funding: Wellcome (WT104908/Z/14/Z, WT107496/Z/15/Z)). 460 students aged 11-16 years were recruited and randomised 1:1 to either MT (N=235) or Psy-Ed (N=225) and assessed preintervention and postintervention on experimental tasks and self-report inventories of affective executive control. The RCT was then extended to evaluate protective functions of MT on mental health assessed after the first UK COVID-19 lockdown. FINDINGS: Results provided no evidence that the version of MT used here improved affective executive control after training or mitigated negative consequences on mental health of the COVID-19 pandemic relative to Psy-Ed. No adverse events were reported. CONCLUSIONS: There is no evidence that MT improves affective control or downstream mental health of young people during stressful periods. CLINICAL IMPLICATIONS: We need to identify interventions that can enhance affective control and thereby young people's mental health.

3.
Sci Rep ; 12(1): 11423, 2022 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-35794169

RESUMO

The field of noninvasive prenatal diagnosis (NIPD) has undergone significant progress over the last decade. Direct haplotyping has been successfully applied for NIPD of few single-gene disorders. However, technical issues remain for triplet-repeat expansions. The objective of this study was to develop an NIPD approach for couples at risk of transmitting dynamic mutations. This method includes targeted enrichment for linked-read libraries and targeted maternal plasma DNA sequencing. We also developed an innovative Bayesian procedure to integrate the Hoobari fetal genotyping model for inferring the fetal haplotype and the targeted gene variant status. Our method of directly resolving parental haplotypes through targeted linked-read sequencing was smoothly performed using blood samples from families with Huntington's disease or myotonic dystrophy type 1. The Bayesian analysis of transmission of parental haplotypes allowed defining the genotype of five fetuses. The predicted variant status of four of these fetuses was in agreement with the invasive prenatal diagnosis findings. Conversely, no conclusive result was obtained for the NIPD of fragile X syndrome. Although improvements should be made to achieve clinically acceptable accuracy, our study shows that linked-read sequencing and parental haplotype phasing can be successfully used for NIPD of triplet-repeat expansion diseases.Trial registration: NCT04698551_date of first registration: 07/01/2021.


Assuntos
Teste Pré-Natal não Invasivo , Teorema de Bayes , Feminino , Haplótipos , Humanos , Polimorfismo de Nucleotídeo Único , Gravidez , Análise de Sequência de DNA , Expansão das Repetições de Trinucleotídeos
4.
Horm Metab Res ; 49(2): 142-146, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27926951

RESUMO

Familial hypocalciuric hypercalcemia (FHH) belongs to the disorders of a disturbed calcium homeostasis. Genetically, the disorder is inherited in an autosomal-dominant trait and represents an inactivating mutation of the calcium sensing receptor (CaSR) gene. We identified a Franconian kindred in which 6 individuals could be tested by molecular genetic means. In 5 individuals of 3 generations, the mutation could be classified as c.1697_1698delTG. This novel germline mutation creates a premature stop codon leading to a loss of 510 amino acids of the protein. The detection of CaSR gene mutations is suitable to differentiate states of hypercalcemia and may help to avoid invasive procedures such as parathyroidectomies.


Assuntos
Éxons/genética , Mutação/genética , Receptores de Detecção de Cálcio/genética , Idoso , Análise Mutacional de DNA , Feminino , Alemanha , Heterozigoto , Humanos , Masculino , Linhagem , Sítios de Splice de RNA/genética
5.
Unfallchirurg ; 119(12): 1031-1042, 2016 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-27896364

RESUMO

Rupture of the proximal tendon enthesis of the hamstring muscle (ICM) accounts for approximately 10% of all injuries of the ICM. It occurs most commonly in athletes and active middle-aged individuals. The complete rupture of all three tendons in active patients is generally seen as an indication for surgical repair of the tendon enthesis; however, the correct diagnosis is often not reached in a timely manner. This can lead to prolonged symptoms with pain, weakness and neuralgia. Operative treatment consists of anchor repair of the tendons resulting in good clinical outcome in several case series. Good knowledge of the anatomy and operative approach are mandatory to avoid complications as well as compliance with a gradual rehabilitation scheme to allow tendon to bone healing. The main aim of this review is to highlight the typical history, clinical presentation and examination technique to reach an immediate clinical diagnosis which should be confirmed with a magnetic resonance imaging (MRI) scan.


Assuntos
Tendões dos Músculos Isquiotibiais/lesões , Tendões dos Músculos Isquiotibiais/cirurgia , Ruptura/diagnóstico , Ruptura/cirurgia , Traumatismos dos Tendões/diagnóstico , Traumatismos dos Tendões/cirurgia , Medicina Baseada em Evidências , Humanos , Pelve/lesões , Pelve/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Tenodese/métodos , Resultado do Tratamento
7.
Forensic Sci Int ; 267: e18, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27259363
8.
J Evol Biol ; 28(12): 2337-48, 2015 12.
Artigo em Inglês | MEDLINE | ID: mdl-26356354

RESUMO

Parthenogenesis (reproduction through unfertilized eggs) encompasses a variety of reproduction modes with (automixis) or without (apomixis) meiosis. Different modes of automixis have very different genetic and evolutionary consequences but can be particularly difficult to tease apart. In this study, we propose a new method to discriminate different types of automixis from population-level genetic data. We apply this method to diploid Artemia parthenogenetica, a crustacean whose reproductive mode remains controversial despite a century of intensive cytogenetic observations. We focus on A. parthenogenetica from two western Mediterranean populations. We show that they are diploid and that markers remain heterozygous in cultures maintained up to ~36 generations in the laboratory. Moreover, parallel patterns of population-wide heterozygosity levels between the two natural populations strongly support the conclusion that diploid A. parthenogenetica reproduce by automictic parthenogenesis with central fusion and low, but nonzero recombination. This settles a century-old controversy on Artemia, and, more generally, suggests that many automictic organisms harbour steep within-chromosome gradients of heterozygosity due to a transition from clonal transmission in centromere-proximal regions to a form of inbreeding similar to self-fertilization in centromere-distal regions. Such systems therefore offer a new avenue for contrasting the genomic consequences of asexuality and inbreeding.


Assuntos
Artemia/fisiologia , Alelos , Animais , Diploide , Heterozigoto , Partenogênese
9.
J Clin Microbiol ; 51(11): 3579-84, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23966484

RESUMO

Assays that expedite the reporting of organism identification and antibiotic susceptibility status in positive blood cultures can fast track interventions that improve clinical outcomes. We evaluated the Verigene Gram-positive blood culture nucleic acid test (BC-GP) in two pediatric hospitals. Positive BacT/Alert Pediatric FAN blood cultures with Gram-positive organisms were tested using the BC-GP in tandem with routine laboratory procedures. To test organisms underrepresented in the clinical blood culture evaluation, blood culture bottles were spiked with diluted organism suspensions at concentrations of 10 to 100 CFU per milliliter. A total of 249 Gram-positive bacterial isolates were recovered from 242 blood cultures. The BC-GP detected Staphylococcus aureus, methicillin-susceptible S. aureus, and methicillin-resistant S. aureus with sensitivities of 100%, 99%, and 100% and specificities of 100%, 100%, and 99.5%, respectively. The BC-GP detected Staphylococcus epidermidis, methicillin-susceptible S. epidermidis, and methicillin-resistant S. epidermidis with sensitivities of 95%, 80%, and 96%, respectively, and 100% specificity. The BC-GP correctly identified 14/15 cases of Enterococcus faecalis and Enterococcus faecium bacteremia and 9 cases of Streptococcus pneumoniae. It misidentified 5/15 clinical blood cultures with Streptococcus mitis/Streptococcus oralis and 1/3 blood cultures spiked with Streptococcus anginosus group as S. pneumoniae. The BC-GP detected a case of Streptococcus pyogenes bacteremia but failed to detect 2/3 clinical blood cultures with Streptococcus agalactiae. BC-GP's rapid accurate detection of Staphylococcus spp., E. faecium, and E. faecalis and its ability to ascertain mecA, vanA, and vanB status may expedite clinical decisions pertaining to optimal antibiotic use. False-positive S. pneumoniae results may warrant reporting of only "Streptococcus spp." when this organism is reported by the BC-GP.


Assuntos
Técnicas Bacteriológicas/métodos , Enterococcus/isolamento & purificação , Infecções por Bactérias Gram-Positivas/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Staphylococcus/isolamento & purificação , Streptococcus/isolamento & purificação , Enterococcus/classificação , Enterococcus/genética , Hospitais Pediátricos , Humanos , Sensibilidade e Especificidade , Staphylococcus/classificação , Staphylococcus/genética , Streptococcus/classificação , Streptococcus/genética
10.
Mol Ecol ; 21(4): 851-61, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22221402

RESUMO

Theory predicts that genetic diversity and genetic differentiation may strongly vary among populations of the same species depending on population turnover and local population sizes. Yet, despite the importance of these predictions for evolutionary and conservation issues, empirical studies comparing high-turnover and low-turnover populations of the same species are scarce. In this study, we used Daphnia magna, a freshwater crustacean, as a model organism for such a comparison. In the southern/central part of its range, D. magna inhabits medium-sized, stable ponds, whereas in the north, it occurs in small rock pools with strong population turnover. We found that these northern populations have a significantly lower genetic diversity and higher genetic differentiation compared to the southern/central populations. Total genetic diversity across populations was only about half and average within-population diversity only about a third of that in southern/central populations. Moreover, an average southern population contains more genetic diversity than the whole metapopulation system in the north. We based our analyses both on silent sites and microsatellites. The similarity of our results despite the contrasting mutation rates of these markers suggests that the differences are caused by contemporary rather than by historical processes. Our findings show that variation in population turnover and population size may have a major impact on the genetic diversity and differentiation of populations, and hence may lead to differences in evolutionary processes like local adaptation, hybrid vigour and breeding system evolution in different parts of a species range.


Assuntos
Daphnia/genética , Variação Genética , Genética Populacional , Taxa de Mutação , Animais , Marcadores Genéticos , Técnicas de Genotipagem , Repetições de Microssatélites , Dados de Sequência Molecular , Densidade Demográfica , Dinâmica Populacional , Análise de Sequência de DNA
11.
Dtsch Med Wochenschr ; 136(38): 1889-94, 2011 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-21915802

RESUMO

OBJECTIVE: The challenge in diagnosing primary hyperparathyroidism (HPT) is to detect hereditary cases before first surgery. About 5% of cases are hereditary and integral component of multiple endocrine neoplasia type 1 and 2 (MEN1/MEN2), hyperparathyroidism-jaw tumor syndrome (HPT-JT), familial hypocalciuric hypercalcemia (FHH), and familial isolated hyperparathyroidism (FIHPT). Aim of this study was to evaluate similarities and differences in hereditary varieties of HPT. PATIENTS: 80 patients with hereditary HPT were evaluated in a retrospective analysis between 1980 and 2010 concerning clinical findings, family history, therapy, biochemical and molecular-genetic findings and follow-up. RESULTS: 80 patients with hereditary HPT are described, 52 belonged to MEN1, 15 to MEN2, 7 to HPT-JT, 4 to FHH and 2 to FIHPT kindreds. Penetrance of HPT was highest in MEN1 (85%), followed by HPT-JT (64%), FHH (28.5%), and MEN2 (8%). Youngest age at diagnosis of HPT was 7 and 16 years in the MEN2/HPT-JT group. Serum Calcium was highest in the HPT-JT group (3.6 mM), recurrencies of HPT were highest in the MEN1 group (40.5%). Parathyroid cancer solely occurred in the HPT-JT group. In single cases HPT occurs in FHH. CONCLUSION: Among the different varieties of hereditary HPT MEN1-HPT is most frequent and carries the utmost recurrence rate. Early diagnosis of HPT-JT syndrome is important because of the occurrence of parathyroid cancer. Single cases of HPT in FHH are described. Preoperative diagnosis of hereditary HPT has therapeutic consequences concerning extent of surgery and implications concerning patient and family care.


Assuntos
Hipercalcemia/congênito , Hiperparatireoidismo Primário/genética , Neoplasias Maxilomandibulares/genética , Neoplasia Endócrina Múltipla Tipo 1/genética , Neoplasia Endócrina Múltipla Tipo 2a/genética , Adenoma/diagnóstico , Adenoma/genética , Adolescente , Adulto , Idoso , Cálcio/sangue , Pré-Escolar , Análise Citogenética , Análise Mutacional de DNA , Diagnóstico Precoce , Feminino , Seguimentos , Testes Genéticos , Humanos , Hipercalcemia/diagnóstico , Hipercalcemia/genética , Hiperparatireoidismo Primário/diagnóstico , Neoplasias Maxilomandibulares/diagnóstico , Masculino , Pessoa de Meia-Idade , Neoplasia Endócrina Múltipla Tipo 1/diagnóstico , Neoplasia Endócrina Múltipla Tipo 2a/diagnóstico , Neoplasias das Paratireoides/diagnóstico , Neoplasias das Paratireoides/genética , Penetrância , Recidiva , Estudos Retrospectivos , Síndrome , Adulto Jovem
12.
J Evol Biol ; 24(7): 1572-83, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21599772

RESUMO

In Daphnia (Cladocera, Crustacea), parthenogenetic reproduction alternates with sexual reproduction. Individuals of both sexes that belong to the same parthenogenetic line are genetically identical, and their sex is determined by the environment. Previously, non-male producing (NMP) genotypes have been described in species of the Daphnia pulex group. Such genotypes can only persist through phases of sexual reproduction if they co-occur with normal (MP) genotypes that produce both males and females, and thus the breeding system polymorphism is similar to gynodioecy (coexistence of females with hermaphrodites), which is well known in plants. Here we show that the same breeding system polymorphism also occurs in Daphnia magna, a species that has diverged from D. pulex more than 100 MY ago. Depending on the population, between 0% and 40% of D. magna females do not produce males when experimentally exposed to a concentration of the putative sex hormone methyl farnesoate that normally leads to male-only clutches. Natural broods of these NMP females never contained males, contrasting with high proportions of male offspring in MP females from the same populations. The results from a series of crossing experiments suggest that NMP is determined by a dominant allele at a single nuclear locus (or a several closely linked loci): NMP × MP crosses always yielded 50% NMP and 50% MP offspring, whereas MP × MP crosses always yielded 100% MP offspring. Based on cytochrome c oxidase subunit I-sequences, we found that NMP genotypes from different populations belong to three highly divergent mitochondrial lineages, potentially representing three independent evolutionary origins of NMP in D. magna. Thus, the evolution of NMP genotypes in cyclical parthenogens may be more common than previously thought. Moreover, MP genotypes that coexist with NMP genotypes may have responded to the presence of the latter by partially specializing on male production. Hence, these populations of D. magna may be a model for an evolutionary transition from a purely environmental to a partially genetic sex determination system.


Assuntos
Evolução Biológica , Daphnia/genética , Daphnia/fisiologia , Partenogênese/genética , Partenogênese/fisiologia , Animais , DNA Mitocondrial/genética , Feminino , Água Doce , Haplótipos , Masculino , Estações do Ano , Razão de Masculinidade
13.
Clin Genet ; 79(5): 489-94, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-20681991

RESUMO

The short stature homeobox (SHOX) gene is located in the pseudoautosomal region 1 of both sex chromosomes. Haploinsufficiency of SHOX leads to different phenotypes ranging from isolated short stature to Léri-Weill syndrome characterized by short stature, mesomelia and Madelung deformity. We describe a family with a SHOX deletion originally located on the Y chromosome and transmitted from father to daughter by crossover during meiosis. The male index patient presented with short stature, mesomelia and mild Madelung deformity. His father had a normal height but slightly disproportionate short legs. The sister of the index patient presented with marked Madelung deformity and normal height. A deletion of the SHOX gene was identified in the male index patient, his father and his sister. Metaphase fluorescence in situ hybridization (FISH) analyses showed a deletion of the SHOX gene on the Y chromosomes of the index patient and his father, and on the X chromosome of his sister, indicating that a meiotic crossover of the SHOX gene region between the X and Y chromosomes had occurred. The pseudoautosomal region 1 is a known recombination 'hot spot' in male meiosis. Published genetic maps indicate high recombination frequency of ∼40% for SHOX in male meiosis leading to pseudoautosomal inheritance.


Assuntos
Transtornos Cromossômicos/genética , Pré-Escolar , Feminino , Transtornos do Crescimento/genética , Proteínas de Homeodomínio/genética , Humanos , Hibridização in Situ Fluorescente , Masculino , Osteocondrodisplasias/genética , Linhagem , Proteína de Homoeobox de Baixa Estatura
14.
J Evol Biol ; 23(11): 2333-45, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20825541

RESUMO

Inbreeding adversely affects life history traits as well as various other fitness-related traits, but its effect on cognitive traits remains largely unexplored, despite their importance to fitness of many animals under natural conditions. We studied the effects of inbreeding on aversive learning (avoidance of an odour previously associated with mechanical shock) in multiple inbred lines of Drosophila melanogaster derived from a natural population through up to 12 generations of sib mating. Whereas the strongly inbred lines after 12 generations of inbreeding (0.75

Assuntos
Aprendizagem da Esquiva/fisiologia , Drosophila melanogaster/genética , Drosophila melanogaster/fisiologia , Variação Genética , Endogamia , Odorantes , Animais , Análise de Sobrevida , Suíça
15.
J Evol Biol ; 22(2): 367-75, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19032494

RESUMO

Allozyme variation at the phosphoglucose isomerase (PGI) locus in the Glanville fritillary butterfly (Melitaea cinxia) is associated with variation in flight metabolic rate, dispersal rate, fecundity and local population growth rate. To map allozyme to DNA variation and to survey putative functional variation in genomic DNA, we cloned the coding sequence of Pgi and identified nonsynonymous variable sites that determine the most common allozyme alleles. We show that these single-nucleotide polymorphisms (SNPs) exhibit significant excess of heterozygotes in field-collected population samples as well as in laboratory crosses. This is in contrast to previous results for the same species in which other allozymes and SNPs were in Hardy-Weinberg equilibrium or exhibited an excess of homozygotes. Our results suggest that viability selection favours Pgi heterozygotes. Although this is consistent with direct overdominance at Pgi, we cannot exclude the possibility that heterozygote advantage is caused by the presence of one or more deleterious alleles at linked loci.


Assuntos
Borboletas/fisiologia , Glucose-6-Fosfato Isomerase/genética , Polimorfismo de Nucleotídeo Único/genética , Animais , Borboletas/genética , Borboletas/metabolismo , Feminino , Variação Genética , Genótipo , Masculino , Fenótipo
16.
J Evol Biol ; 21(4): 1068-78, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18462312

RESUMO

Although there is little doubt that hosts evolve to reduce parasite damage, little is known about the evolutionary time scale on which host populations may adapt under natural conditions. Here we study the effects of selection by the microsporidian parasite Octosporea bayeri on populations of Daphnia magna. In a field study, we infected replicated populations of D. magna with the parasite, leaving control populations uninfected. After two summer seasons of experimental evolution (about 15 generations), the genetic composition of infected host populations differed significantly from the control populations. Experiments revealed that hosts from the populations that had evolved with the parasite had lower mortality on exposure to parasite spores and a higher competitive ability than hosts that had evolved without the parasite. In contrast, the susceptibility of the two treatment groups to another parasite, the bacterium Pasteuria ramosa, which was not present during experimental evolution of the populations, did not differ. Fitness assays in the absence of parasites revealed a higher fitness for the control populations, but only under low population density with high resource availability. Overall, our results show that, under natural conditions, Daphnia populations are able to adapt rapidly to the prevailing conditions and that this evolutionary change is specific to the environment.


Assuntos
Evolução Biológica , Daphnia/genética , Daphnia/parasitologia , Alelos , Animais , Seleção Genética
17.
Gesundheitswesen ; 70(3): 129-36, 2008 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-18415920

RESUMO

OBJECTIVE: As the levels of care within long-term nursing care regulations are defined according to limitations in performing fundamental activities of daily living, the extent to which medically diagnosed cognitive, emotional and behavioral dementia symptoms are taken into account in the grading, should be investigated. METHOD: 390 patients with mild to moderate dementia from the Mid-Franconia region, were included into the IDA ("Initiative Demenzversorgung in Allgemeinmedizin") study by specially trained general practitioners. The GPs had diagnosed dementia and noted the accompanying signs at baseline. In an interview with the caregiver, the Barthel Index was used to measure the level of help required with fundamental daily tasks. Predictors for grading were set down using logistic regression analysis. RESULTS: Where one accompanying sign is present, about half the patients had not been assigned a grade. Besides the Barthel Index, the presence of agitation and agnosia and the absence of depression are the only independent predictors for grading. All other symptoms, impairment of the executive function, loss of orientation, aphasia, anxiety, sleeplessness, aggressiveness and tendency to wander, have no significant predictive value. CONCLUSION: In the future development of nursing care insurance, the need for nursing care should be redefined using symptoms associated with dementia, particularly sleeplessness, aggressiveness and the tendency to wander as inclusion criteria. This is a prerequisite of improving the care available to dementia patients in the long term and also of expanding relief measures for family caregiver.


Assuntos
Atitude do Pessoal de Saúde , Demência/diagnóstico , Demência/terapia , Definição da Elegibilidade/estatística & dados numéricos , Cuidados de Enfermagem/estatística & dados numéricos , Índice de Gravidade de Doença , Idoso de 80 Anos ou mais , Demência/classificação , Demência/epidemiologia , Feminino , Alemanha/epidemiologia , Humanos , Masculino
18.
Exp Clin Endocrinol Diabetes ; 115(9): 616-8, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17943698

RESUMO

Pheochromocytomas are rare catecholamine-secreting, chromaffin tumors of the autonomic nervous system. Most pheochromocytomas are sporadic, but up to 24% of pheochromocytomas are part of a familial disorder. Here we describe a female patient, who presented to our outpatient clinic 18 years after removal of a pheochromocytoma of the left adrenal gland in China. Now she reported flank pain on the left side and elevated blood pressure. 24-hour urinary catecholamines, metanephrines, and normetanephrines as well as plasma-norepinephrine were elevated. The transabdominal ultrasonography revealed a tumor with reduced echogenicity in the left suprarenal region, which was suspected to be a recurrent pheochromocytoma. This finding was confirmed by MRT and J (123)-MIBG-scan. Parathyroid hormone (PTH) and calcitonin were in the normal range. After surgical excision, histological examination of the adrenal mass proved to be a pheochromocytoma. Molecular genetic analysis with sequencing of the succinate dehydrogenase type B (SDHB) gene revealed a formerly unknown mutation of codon 214 (CAG-->TAG) leading to an amino acid change of glutamine to a stop-Codon (Q214X-mutation) in exon 6. This case report highlights the necessity of re-evaluating patients with nonsyndromic pheochromocytoma who are diagnosed without genetic testing to estimate the risk of a relapse and to initiate testing of first-degree relatives.


Assuntos
Neoplasias das Glândulas Suprarrenais/genética , Proteínas Ferro-Enxofre/genética , Recidiva Local de Neoplasia/genética , Feocromocitoma/genética , Mutação Puntual , Succinato Desidrogenase/genética , Neoplasias das Glândulas Suprarrenais/cirurgia , Adulto , DNA de Neoplasias/química , DNA de Neoplasias/genética , Feminino , Humanos , Proteínas Ferro-Enxofre/química , Masculino , Recidiva Local de Neoplasia/cirurgia , Linhagem , Feocromocitoma/cirurgia , Análise de Sequência de DNA , Succinato Desidrogenase/química
19.
J Evol Biol ; 20(3): 881-91, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17465899

RESUMO

The genetic basis of fitness reduction associated with inbreeding is still poorly understood. Here we use associations between allozyme genotypes and fitness to investigate the genetic basis of inbreeding depression in experimental outdoor populations of the water flea, Daphnia magna. In Daphnia, a phase of clonal reproduction follows hatching from sexually produced resting eggs, and changes in genotype frequencies during the clonal phase can be used to estimate fitness. Our experiment resembles natural colonization of ponds in that single clones colonize an empty pool, expand asexually and produce sexual offspring by selfing (sisters mate with their clonal brothers). These offspring diapause and form populations consisting of selfed sibships in the following spring. In 12 of 13 experimental populations, genotypes of selfed hatchlings after diapause conformed to Mendelian expectations. During the subsequent ca. 10 asexual generations, however, genotype frequencies changed significantly at 19 of 27 single loci studied within populations, mostly in favour of heterozygotes, with heterozygosity at multiple loci affecting the change in genotype frequency multiplicatively. Because variance in heterozygosity among siblings at a given marker reflects only heterozygosity in the chromosomal region around this marker, our results suggest that selection at fitness-associated loci in the chromosomal regions near the markers were responsible for these changes. The genotype frequency changes were more consistent with selection acting on linked loci than on the allozymes themselves. Taken together, the evidence for abundant selection in the chromosomal regions of the markers and the fact that changes in genotype frequencies became apparent only after several generations of clonal selection, point to a genetic load consisting of many alleles of small or intermediate effects, which is consistent with the strong genetic differentiation and repeated genetic bottlenecks in the metapopulation from which the animals for this study were obtained.


Assuntos
Daphnia/genética , Genótipo , Endogamia , Seleção Genética , Animais , Daphnia/fisiologia , Epistasia Genética , Feminino , Frequência do Gene , Marcadores Genéticos , Heterozigoto , Desequilíbrio de Ligação , Masculino , Partenogênese , Polimorfismo Genético , Reprodução Assexuada
20.
Exp Clin Endocrinol Diabetes ; 114(8): 397-405, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17039419

RESUMO

The calcium-sensing receptor has a key role in calcium homeostasis, it is involved in the regulation of the serum calcium level within minutes via the secretion and action of parathyroid and the excretion of calcium in the kidney in a negative feedback manner. Mutations of the calcium sensing receptor gene leads to inactivating and activating mutations resulting in diseases with hypercalcaemia and hypocalcaemia. The loss of function mutations are associated with familial benign hypocalciuric hypercalcaemia (FHH), an autosomal dominant disease characterised by lifelong mild hypercalcaemia, low urinary calcium excretion, and inappropriate high parathyroid hormone levels, sometimes difficult to distinguish from mild asymptomatic primary hyperparathyroidism. Patients with FHH did not profit from parathyroidectomy, a calcium lowering therapy is not necessary. The gain of function mutations of the calcium-sensing receptor are associated with autosomal dominant hypocalcaemia (ADH), a disease characterised by a generally asymptomatic hypocalcaemia, inappropriately high urinary calcium excretion and normal PTH levels. A therapy to raise the serum calcium concentration has to be done carefully and is only indicated in symptomatic patients, because of enhancement of hypercalciuria with the risk of nephrocalcinosis and nephrolithiasis. Molecular genetic analysis of the calcium sensing receptor gene facilitates the sometimes difficult diagnosis. The development of compounds modulating the calcium sensing receptor function and thereby the section of PTH may become an important role in treatment of diseases of calcium metabolism.


Assuntos
Rim/fisiologia , Receptores de Detecção de Cálcio/fisiologia , Adulto , Cálcio/urina , Humanos , Hipercalcemia/fisiopatologia , Hiperparatireoidismo/congênito , Hiperparatireoidismo/fisiopatologia , Hipocalcemia/fisiopatologia , Hipoparatireoidismo/fisiopatologia , Recém-Nascido , Receptores de Detecção de Cálcio/química , Receptores de Detecção de Cálcio/genética , Valores de Referência
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