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1.
Infect Immun ; 89(3)2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33361201

RESUMO

The Enteritidis and Dublin serovars of Salmonella enterica are phylogenetically closely related yet differ significantly in host range and virulence. S Enteritidis is a broad-host-range serovar that commonly causes self-limited gastroenteritis in humans, whereas S Dublin is a cattle-adapted serovar that can infect humans, often resulting in invasive extraintestinal disease. The mechanism underlying the higher invasiveness of S Dublin remains undetermined. In this work, we quantitatively compared the proteomes of clinical isolates of each serovar grown under gut-mimicking conditions. Compared to S Enteritidis, the S Dublin proteome was enriched in proteins linked to response to several stress conditions, such as those encountered during host infection, as well as to virulence. The S Enteritidis proteome contained several proteins related to central anaerobic metabolism pathways that were undetected in S Dublin. In contrast to what has been observed in other extraintestinal serovars, most of the coding genes for these pathways are not degraded in S Dublin. Thus, we provide evidence that S Dublin metabolic functions may be much more affected than previously reported based on genomic studies. Single and double null mutants in stress response proteins Dps, YciF, and YgaU demonstrate their relevance to S Dublin invasiveness in a murine model of invasive salmonellosis. All in all, this work provides a basis for understanding interserovar differences in invasiveness and niche adaptation, underscoring the relevance of using proteomic approaches to complement genomic studies.


Assuntos
Anaerobiose/genética , Proteômica , Salmonella enteritidis/genética , Salmonella enteritidis/patogenicidade , Sorogrupo , Estresse Fisiológico/genética , Virulência/genética , Variação Genética , Genômica , Especificidade de Hospedeiro , Humanos , Infecções por Salmonella/genética , Infecções por Salmonella/patologia
2.
Phys Biol ; 18(1): 016003, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33049726

RESUMO

Parkinson's disease (PD) is a chronic, progressive neurodegenerative disease and represents the most common disease of this type, after Alzheimer's dementia. It is characterized by motor and nonmotor features and by a long prodromal stage that lasts many years. Genetic research has shown that PD is a complex and multisystem disorder. To capture the molecular complexity of this disease we used a complex network approach. We maximized the information entropy of the gene co-expression matrix betweenness to obtain a gene adjacency matrix; then we used a fast greedy algorithm to detect communities. Finally we applied principal component analysis on the detected gene communities, with the ultimate purpose of discriminating between PD patients and healthy controls by means of a random forests classifier. We used a publicly available substantia nigra microarray dataset, GSE20163, from NCBI GEO database, containing gene expression profiles for 10 PD patients and 18 normal controls. With this methodology we identified two gene communities that discriminated between the two groups with mean accuracy of 0.88 ± 0.03 and 0.84 ± 0.03, respectively, and validated our results on an independent microarray experiment. The two gene communities presented a considerable reduction in size, over 100 times, compared to the initial network and were stable within a range of tested parameters. Further research focusing on the restricted number of genes belonging to the selected communities may reveal essential mechanisms responsible for PD at a network level and could contribute to the discovery of new biomarkers for PD.


Assuntos
Biologia Computacional/métodos , Expressão Gênica , Marcadores Genéticos , Doença de Parkinson/genética , Substância Negra/metabolismo , Algoritmos , Entropia , Humanos , Substância Negra/patologia , Substância Negra/fisiopatologia
3.
Eur J Paediatr Dent ; 19(4): 287-294, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30567445

RESUMO

BACKGROUND: Bruxism is a condition that results from hyperactivity in the central nervous system, and factors such as stress or other anxious conditions increase the frequency of episodes. When bruxism occurs at a young age, tooth wear can occur. The extent of wear can lead to the need for restorative dentistry and prosthetic treatments to restore the morphological and functional integrity of the teeth, with high costs associated with such treatments. CASE REPORT: A healthy 15-year-old boy presented to the orthodontist observation. His incisal ridges appeared thin, without mamelons, and with increased translucency. For treatment, the authors used only the Functional Plane of Monaco (FPM), a device which he had to wear 16 hours during the day. CONCLUSION: The orthodontist successfully treated an orthopaedic/orthodontic case with the FPM device.


Assuntos
Bruxismo/prevenção & controle , Aparelhos Ortodônticos Funcionais , Transtornos da Articulação Temporomandibular/prevenção & controle , Adolescente , Humanos , Masculino
4.
J Fish Dis ; 40(5): 629-635, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27523735

RESUMO

Embryos at shield stage and larvae at protruding mouth stage were exposed to different concentrations of aluminium chloride (AlCl3 ) for 72 h with the purpose to analyse their phenotype and lethality. After 24, 48 and 72 h of treatment, higher toxicity of the metal was observed on larvae with minimal lethal concentration of 0.25, 0.20 and 0.08 mm, respectively, while for embryos the corresponding values were 40, 25 and 16 mm. We observed pericardial oedema and alteration of heart rate in 50% of larvae after 48 h of exposure to 100 µm. In larvae exposed to the same concentration, there was also a neurological injury at the level of glial cells, with the number of glial fibrillary acidic protein-positive cells being significantly reduced. This study confirms the toxic nature of this metal and shows that aluminium could also interestingly represent a cardiotoxin in addition to its neurotoxic ability.


Assuntos
Compostos de Alumínio/toxicidade , Astrócitos/efeitos dos fármacos , Cloretos/toxicidade , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/metabolismo , Cloreto de Alumínio , Animais , Astrócitos/metabolismo , Biomarcadores/metabolismo , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Peixe-Zebra/crescimento & desenvolvimento , Proteínas de Peixe-Zebra/metabolismo
5.
Phys Rev Lett ; 116(24): 241105, 2016 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-27367381

RESUMO

Cosmic-ray electrons and positrons are a unique probe of the propagation of cosmic rays as well as of the nature and distribution of particle sources in our Galaxy. Recent measurements of these particles are challenging our basic understanding of the mechanisms of production, acceleration, and propagation of cosmic rays. Particularly striking are the differences between the low energy results collected by the space-borne PAMELA and AMS-02 experiments and older measurements pointing to sign-charge dependence of the solar modulation of cosmic-ray spectra. The PAMELA experiment has been measuring the time variation of the positron and electron intensity at Earth from July 2006 to December 2015 covering the period for the minimum of solar cycle 23 (2006-2009) until the middle of the maximum of solar cycle 24, through the polarity reversal of the heliospheric magnetic field which took place between 2013 and 2014. The positron to electron ratio measured in this time period clearly shows a sign-charge dependence of the solar modulation introduced by particle drifts. These results provide the first clear and continuous observation of how drift effects on solar modulation have unfolded with time from solar minimum to solar maximum and their dependence on the particle rigidity and the cyclic polarity of the solar magnetic field.

6.
Heredity (Edinb) ; 117(5): 348-357, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27436523

RESUMO

Wild boar (Sus scrofa), one of the most widespread wildlife species, has entered a stage of continuous growth in Europe, and could even be considered a pest species. We analysed microsatellite variability in 723 wild boars from across Europe, including the northern Dinaric Balkans. Our aims were: (1) to define the population structure of wild boars in the Balkans and its relation with other European populations; (2) to estimate effective populations sizes, levels of intra- and inter-population diversity, inbreeding migration and gene flow patterns; (3) to test subpopulations for bottlenecks; (4) to interpret these results in light of current knowledge about the demographic history of wild boars in Europe; and (5) to discuss the relevance of these findings for management and conservation. Strong population structuring was observed and 14 subpopulations were revealed. High genetic diversity was found, and besides the well-known identity of the Italian populations of Sardinia and Castelporziano, we bring new insights into other potential relevant, refugial populations such as Littoral Slovenia, South Portugal, North-western Iberia and an entire cluster in the Balkans. There was evidence of gene flow going from these refugial subpopulations towards less peripheral and more admixed subpopulations. Recent population bottlenecks and expansions were detected, mostly in the peninsular refuge subpopulations. The results are consistent with the fluctuations of wild boar numbers in Europe since the beginning of the twentieth century. These results should be taken into account in future conservation and management plans for wild boar populations in Europe.


Assuntos
Fluxo Gênico , Variação Genética , Genética Populacional , Sus scrofa/genética , Animais , Península Balcânica , Conservação dos Recursos Naturais , Europa (Continente) , Frequência do Gene , Técnicas de Genotipagem , Endogamia , Repetições de Microssatélites , Modelos Genéticos , Modelos Estatísticos , Densidade Demográfica , Dinâmica Populacional
7.
Occup Environ Med ; 73(11): 761-771, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27456156

RESUMO

OBJECTIVES: To investigate mortality and cancer incidence of paid male Australian firefighters and of subgroups of firefighters by era of first employment, duration of employment and number and type of incidents attended. METHODS: Participating fire agencies supplied records of individual firefighters including their job histories and incidents attended. The cohort was linked to the Australian National Death Index and Australian Cancer Database. SMRs and SIRs were calculated. Firefighters were grouped into tertiles by duration of employment and by number of incidents attended and relative mortality ratios and relative incidence ratios calculated. Analyses were carried out separately for full-time and part-time male firefighters. RESULTS: Compared to the Australian population, there were significant increases in overall risk of cancer, for all paid firefighters SIR 1.09 (95% CI 1.03 to 1.14), in prostate cancer, full-time firefighters 1.23 (95% CI 1.10 to 1.37), part-time 1.51 (1.28 to 1.77), and melanoma full-time 1.45 (95% CI 1.26 to 1.66), part-time firefighters 1.43 (95% CI 1.15 to 1.76). Kidney cancer was associated with longer service in internal analyses for paid firefighters. Prostate cancer was associated with longer service and increased attendance at fires, particularly structural fires for full-time firefighters.The overall risk of mortality was significantly decreased and almost all major causes of death were significantly reduced for paid firefighters. CONCLUSIONS: Male paid firefighters have an increased risk of cancer. They have reduced mortality compared with the general population, which is likely to be a result of a strong healthy worker effect and likely lower smoking rates among firefighters compared with the Australian population.


Assuntos
Bombeiros/estatística & dados numéricos , Neoplasias/epidemiologia , Doenças Profissionais/epidemiologia , Adulto , Austrália/epidemiologia , Causas de Morte , Estudos de Coortes , Bases de Dados Factuais , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Neoplasias/mortalidade , Doenças Profissionais/mortalidade , Exposição Ocupacional/efeitos adversos , Fatores de Risco , Adulto Jovem
8.
J Fish Dis ; 39(3): 295-308, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25865023

RESUMO

The aim of this study was the assessment of histological and hormonal changes induced in the European eel from environmental concentrations of cocaine. Silver eels were exposed to 20 ng L(-1) of cocaine during 50 days; at the same time, control, vehicle control and two post-exposure recovery groups (3 and 10 days) were made. The general morphology of the skin and the intestine, and the plasma levels of prolactin, cortisol and dopamine were evaluated. In the skin, cocaine decreased the number and size of mucous cells, increased the thickness of the epidermis and altered the club cells and the basal lamina. In the intestine, cocaine increased the thickness of the epithelium and the number of mucous cells and reactivated the structure of the intestine and of the intestinal musculature. Moreover, cocaine increased plasma prolactin, cortisol and dopamine levels. These results suggest that cocaine induced histological changes, directly and/or through the hormonal changes observed. Considering the complex life cycle of the eel, the changes induced by cocaine in the skin, the intestine and the endocrine system could threaten the ability of the eel to successfully migrate and reproduce.


Assuntos
Anguilla , Cocaína/toxicidade , Sistema Endócrino/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Pele/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Dopamina/sangue , Exposição Ambiental , Hidrocortisona/sangue , Prolactina/sangue
9.
Occup Med (Lond) ; 66(7): 536-42, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27371948

RESUMO

BACKGROUND: An investigation into concerns about possible health effects of fire training practices at an Australian training facility recommended a study to investigate the risk of cancer and mortality of those with risk of chronic occupational exposure to several chemicals. AIMS: To investigate mortality and cancer incidence in firefighters at the Country Fire Authority (CFA) Fiskville training facility, Victoria, Australia, between 1971 and 1999. METHODS: CFA supplied human resources records, supplemented by self-reported information for a retrospective cohort, and allocated firefighters to low, medium or high groups based on probability of exposure. We linked the cohort to state and national cancer and mortality data. We calculated standardized mortality ratios and standardized cancer incidence ratios (SIRs). RESULTS: The high group (n = 95) had a clearly increased risk of overall cancers SIR = 1.85 (95% CI 1.20-2.73), testicular cancer SIR = 11.9 (1.44-42.9) and melanoma SIR = 4.59 (1.68-9.99) relative to the population of Victoria. Brain cancer was significantly increased for the medium group (n = 256): SIR = 5.74 (1.56-14.7). Mortality was significantly reduced for all groups. CONCLUSIONS: Dealing with supplied records can be problematic but despite the small numbers, we identified an increased risk of cancer for the high group. The mortality data suggested that there was under-ascertainment for the medium and low groups which underestimated risk and a possible reporting bias for brain cancer. Small cohorts can still provide statistically significant findings when investigating locations for cancer risk.


Assuntos
Bombeiros/educação , Incidência , Neoplasias/mortalidade , Exposição Ocupacional/efeitos adversos , Adulto , Austrália/epidemiologia , Estudos de Coortes , Feminino , Humanos , Masculino , Melanoma/epidemiologia , Melanoma/etiologia , Neoplasias/epidemiologia , Neoplasias/etiologia , Estudos Retrospectivos , Neoplasias Testiculares/epidemiologia , Neoplasias Testiculares/etiologia , Universidades/organização & administração , Recursos Humanos
10.
Eur J Paediatr Dent ; 17(2): 123-8, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27377110

RESUMO

BACKGROUND: This work seeks to provide information on the utility of surface electromyography (SEMG) as an aid for diagnosing orthodontic conditions. Classic orthodontic monitoring by radiography, plaster models, cephalometry, and photography can be improved by using SEMG before and during treatment, to prevent clinical worsening and relapses. CASE REPORT: This paper presents the SEMG results for a 10-year-old female patient, orthodontically treated by extraoral traction (EOT). Significant muscular variations in the patient's EMG were observed as she changed different postures and as headgear device was used. CONCLUSION: SEMG should be performed prior to the orthodontic treatment to assess the neuromuscular patient's pattern, in order to prevent strain induced by extraoral forces. EMG can be a valid aid for evaluating the patient's neuromuscular condition before, during, and after orthodontic treatment.


Assuntos
Ortodontia , Criança , Eletromiografia , Aparelhos de Tração Extrabucal , Feminino , Humanos
11.
Phys Rev Lett ; 115(11): 111101, 2015 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-26406816

RESUMO

In this work we present results of a direct search for strange quark matter (SQM) in cosmic rays with the PAMELA space spectrometer. If this state of matter exists it may be present in cosmic rays as particles, called strangelets, having a high density and an anomalously high mass-to-charge (A/Z) ratio. A direct search in space is complementary to those from ground-based spectrometers. Furthermore, it has the advantage of being potentially capable of directly identifying these particles, without any assumption on their interaction model with Earth's atmosphere and the long-term stability in terrestrial and lunar rocks. In the rigidity range from 1.0 to ∼1.0×10^{3} GV, no such particles were found in the data collected by PAMELA between 2006 and 2009. An upper limit on the strangelet flux in cosmic rays was therefore set for particles with charge 1≤Z≤8 and mass 4≤A≤1.2×10^{5}. This limit as a function of mass and as a function of magnetic rigidity allows us to constrain models of SQM production and propagation in the Galaxy.

12.
Int J Immunopathol Pharmacol ; 28(1): 114-8, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25816413

RESUMO

Transcutaneous electrical nerve stimulation (TENS) is extensively used as pain relief through endorphins release. Moreover, recent findings showed a role in the activation of the autonomic nervous system (ANS); it was evidenced by modification in the heart rate variability and ANS-related marker. The objective of this pilot study is to evaluate salivary alpha amylase (sAA) as a marker of stress in two groups of healthy subjects, one receiving ultra-low frequency transcutaneous electrical nerve stimulation (ULF-TENS) and one without stimulation. Sixty healthy people were enrolled. The test group consisted of 30 participants (15 men, 15 women). The control group consisted of 30 participants (15 men, 15 women). Statistical analysis showed that sAA levels were statistically different between men and women independently from TENS; we hypothesize that treatment could influence sAA levels because it is thought to activate µ opioid receptors. The results of this study seem to indicate that the analysis of sAA, through a non-invasive saliva sample, could be an efficient aid for understanding the functions of the autonomic nervous system.


Assuntos
Biomarcadores/metabolismo , Saliva/metabolismo , Adulto , Sistema Nervoso Autônomo/metabolismo , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Projetos Piloto , Receptores Opioides mu/metabolismo , Estimulação Elétrica Nervosa Transcutânea/métodos , Adulto Jovem
14.
Clin Oral Implants Res ; 26(4): e8-e16, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24382358

RESUMO

OBJECTIVE: The aim of the present systematic review and meta-analysis was to assess the role of periodontal disease as a risk factor for implant loss, peri-implantitis and implant-bone loss. MATERIALS AND METHODS: Six electronic database and a manual search resulted in 7391 unique publications; after selection only 16 studies were included in systematic review. Dichotomous data were expressed as risk ratio (RR) and 95% confidence interval (CI), while continuous data were expressed as standardized mean difference (SMD). Due to the expected inter-study heterogeneity, a random effect model was used for both type of data. The pooled effect was considered significant for a P < 0.05. RESULTS: Meta-analysis revealed that an higher and significant risk for implant loss was present in patients affected by PD (RR: 1.69, 95% CI: 1.31-2.17, P < 0.0001). A higher and significant IBL was present in patients with periodontal disease, when compared with patients periodontally healthy (SMD: 0.38, 95% CI: 0.18-0.58, P = 0.0002). Patients periodontally compromised showed an increased risk of PI, when compared with patients without periodontitis (RR: 2.17, 95% CI: 1.51-3.12, P < 0.0001) No evidence of significant heterogeneity was detected for the three outcomes. CONCLUSION: Strong evidence suggests that periodontitis is a risk factor for implant loss; moderate evidence revealed that periodontitis is a risk factor for peri-implantitis and that patients with periodontitis have higher implant-bone loss.


Assuntos
Perda do Osso Alveolar/etiologia , Implantes Dentários , Falha de Restauração Dentária , Peri-Implantite/etiologia , Periodontite/complicações , Humanos , Fatores de Risco
15.
J Periodontal Res ; 49(1): 10-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23668676

RESUMO

BACKGROUND: Metronidazole (MET) has been suggested as an adjunct to scaling and root planing (SRP) in the treatment of chronic periodontitis. However, its clinical effectiveness and effects on periodontal pathogens remain to be defined. The present meta-analysis assessed the scientific evidence concerning the effect of MET adjunctive to SRP as compared to SRP alone. METHODS: A literature search of electronic databases was performed for articles published through December 16, 2012, followed by a manual search of several dental journals. A meta-analysis was conducted according to recommendations of the Cochrane Collaboration and PRISMA. Weighted mean differences (MDs) and 95% confidence intervals (CIs) were calculated for probing depth reduction, clinical attachment level gain, bleeding on probing index and suppuration. All outcomes were evaluated as changes from baseline to the end of follow-up. Heterogeneity was assessed with the chi-squared-based Cochran Q test and I(2) statistic. The level of significance was set at p < 0.05. RESULTS: After the study selection process, six randomized clinical trials were included in the meta-analysis. The results of the meta-analysis indicated that SRP + MET provided additional benefits when compared to SRP alone in terms of probing depth reduction (MD, 0.18; 95% CI, 0.09-0.28; p < 0.05) and clinical attachment level gain (MD, 0.10; 95% CI, 0.08-0.12; p < 0.05). No evidence of heterogeneity was detected. CONCLUSION: The meta-analysis results seem to support the effectiveness of adjunctive MET with SRP compared to SRP alone. However, given the low number of included studies and limitations of meta-analysis, future studies are needed to confirm these results.


Assuntos
Anti-Infecciosos/uso terapêutico , Periodontite Crônica/terapia , Raspagem Dentária/métodos , Metronidazol/uso terapêutico , Aplainamento Radicular/métodos , Periodontite Crônica/tratamento farmacológico , Terapia Combinada , Humanos , Perda da Inserção Periodontal/terapia , Bolsa Periodontal/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto
16.
Eur J Paediatr Dent ; 15(3): 271-4, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25306143

RESUMO

AIM: To assess the microbial level of Streptococcus Mutans and Lactobacillus spp. during rapid palatal expansion, and compare the data with untreated control patients. STUDY DESIGN: Thirty patients aged between 6-9 years were enrolled in this study (15 males and 15 females). The patients were divided into three groups: 10 patients were treated with rapid palatal expander (RPE) (Test Group 1), 10 patients were treated with Mc Namara expander, and 10 patients were enrolled in the control untreated group. Whole stimulated saliva was collected from each patient at three time points: before initiation of expansion therapy (baseline at T0), after 3 months (T1), after initiation of treatment, and after 6 months from T0 (T2). The protocol of rapid palatal expansion for the two groups was as follows: at placement of the expander 4 activations were performed by the orthodontist (1 mm expansion), followed by 4 activations per day by the parents (two in the morning and two in the evening, 1 mm per day total) to be repeated for 7 days. RESULTS: Statistics: In this study a different trend in the microbial colonisation for the two treated groups was observed. In the Test Group 1, in which patients were treated with the RPE, there was a significant difference between Strp T0 T1 and between Strp T0 and T2 (p< 0.05). There was also a significant difference between LAC T1 T0 and LAC T2 and T0 (p<0.05). In the Test Group 2, treated with McNamara expanders, it was found was a significant difference between LAC T2 T0 and LAC T1 T0. In the same group it was also found a significant difference between Strp T2 T0; T1 T0; T1 T2 (p<0.05). CONCLUSION: The level of the various species of bacteria changes during rapid palatal expansion, and this seems to depend on the type of orthodontic expander. During rapid palatal expansion treatment it is also advisable a periodical microbial monitoring using in-office bacteria tests.


Assuntos
Carga Bacteriana , Lactobacillus/isolamento & purificação , Técnica de Expansão Palatina , Saliva/microbiologia , Streptococcus mutans/isolamento & purificação , Soluções Tampão , Criança , Índice de Placa Dentária , Feminino , Seguimentos , Humanos , Masculino , Higiene Bucal , Desenho de Aparelho Ortodôntico , Técnica de Expansão Palatina/instrumentação , Saliva/metabolismo , Taxa Secretória/fisiologia
17.
Eur J Paediatr Dent ; 25(1): 57-60, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38353510

RESUMO

AIM: This paper aims to verify the effectiveness of using elastodontic devices in the treatment of malocclusions in growing patients. An English-language literature search was conducted. The following electronic databases were selected for searching from 2020 to June 2023: PubMed, Web of Science, and Scopus. Eight articles were included based on the inclusion and exclusion criteria. The articles examined highlight the ability of elastodontic devices to act in cases of malocclusion in a safe, simple and more comfortable way for the young patient. However, there is a lack of knowledge about this technique, so this study aims to review the most recent literature to provide the scientific community with new knowledge.


Assuntos
Má Oclusão , Humanos , Má Oclusão/terapia
18.
Phys Rev Lett ; 111(8): 081102, 2013 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-24010424

RESUMO

Precision measurements of the positron component in the cosmic radiation provide important information about the propagation of cosmic rays and the nature of particle sources in our Galaxy. The satellite-borne experiment PAMELA has been used to make a new measurement of the cosmic-ray positron flux and fraction that extends previously published measurements up to 300 GeV in kinetic energy. The combined measurements of the cosmic-ray positron energy spectrum and fraction provide a unique tool to constrain interpretation models. During the recent solar minimum activity period from July 2006 to December 2009, approximately 24,500 positrons were observed. The results cannot be easily reconciled with purely secondary production, and additional sources of either astrophysical or exotic origin may be required.

19.
Nat Genet ; 18(2): 168-70, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9462748

RESUMO

Between 2 and 5% of children who are otherwise unimpaired have significant difficulties in acquiring expressive and/or receptive language, despite adequate intelligence and opportunity. While twin studies indicate a significant role for genetic factors in developmental disorders of speech and language, the majority of families segregating such disorders show complex patterns of inheritance, and are thus not amenable for conventional linkage analysis. A rare exception is the KE family, a large three-generation pedigree in which approximately half of the members are affected with a severe speech and language disorder which appears to be transmitted as an autosomal dominant monogenic trait. This family has been widely publicised as suffering primarily from a defect in the use of grammatical suffixation rules, thus supposedly supporting the existence of genes specific to grammar. The phenotype, however, is broader in nature, with virtually every aspect of grammar and of language affected. In addition, affected members have a severe orofacial dyspraxia, and their speech is largely incomprehensible to the naive listener. We initiated a genome-wide search for linkage in the KE family and have identified a region on chromosome 7 which co-segregates with the speech and language disorder (maximum lod score = 6.62 at theta = 0.0), confirming autosomal dominant inheritance with full penetrance. Further analysis of microsatellites from within the region enabled us to fine map the locus responsible (designated SPCH1) to a 5.6-cM interval in 7q31, thus providing an important step towards its identification. Isolation of SPCH1 may offer the first insight into the molecular genetics of the developmental process that culminates in speech and language.


Assuntos
Cromossomos Humanos Par 7 , Transtornos da Linguagem/genética , Distúrbios da Fala/genética , Mapeamento Cromossômico , Feminino , Ligação Genética , Marcadores Genéticos , Genótipo , Humanos , Escore Lod , Masculino , Linhagem
20.
Nat Genet ; 3(1): 14-9, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8490646

RESUMO

Menkes disease is a lethal-X linked recessive disorder associated with copper metabolism disturbance. We have recently mapped two chromosome breakpoints related to this disease in a 1 megabase yeast artificial chromosome contig at Xq13.3. We now report the construction of a phage contig and the isolation of candidate partial cDNAs for the Menkes disease gene. The candidate gene expresses an 8 kb message in all investigated tissues, and deletions were detected in 16% of 100 unrelated Menkes patients. The deduced partial protein sequence shared the GMTCXXC motif with bacterial metal resistance operons, suggesting a potential heavy metal binding protein. These findings should lead to more accurate prenatal diagnosis of this severe disease and a better understanding of the cellular homeostasis of essential heavy metals.


Assuntos
Adenosina Trifosfatases/genética , Proteínas de Transporte/genética , Proteínas de Transporte de Cátions , Síndrome dos Cabelos Torcidos/genética , Metais/metabolismo , Proteínas Recombinantes de Fusão , Adenosina Trifosfatases/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Southern Blotting , Proteínas de Transporte/metabolismo , Células Cultivadas , Clonagem Molecular , ATPases Transportadoras de Cobre , DNA , Feminino , Humanos , Masculino , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Cromossomo X
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