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1.
JDR Clin Trans Res ; 5(2): 109-117, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31238010

RESUMO

BACKGROUND: Children's oral health-related quality of life (COHQoL) measures are well known and widely used. However, rigorous systematic reviews of these measures and analyses of their quality are in absence. OBJECTIVES: To systematically review and quantitatively assess the quality of COHQoL measures through a scoping review. DATA SOURCES: Systematic literature search of PubMed, CINAHL (Cumulative Index to Nursing and Allied Health Literature), EMBASE (Excerpta Medica database), HaPI (Health and Psychosocial Instruments), and DOSS (Dentistry and Oral Sciences Source). STUDY ELIGIBILITY: The measure's focus was COHQoL; the child age ranged from 5 to 14 years; the publication was either a research article or a systematic review and related to caries; and it was written in English or had an English abstract. Two authors independently selected the studies. Disagreements were reconciled by group discussions with a third author. APPRAISAL: The International Society for Quality of Life Research minimum standards for patient-reported outcome measures were used for quality appraisal. SYNTHESIS: Descriptive analysis. RESULTS: We identified 18 measures. Their quality scores ranged from 9.5 to 15.0 on a scale of 16. The quality appeared to bear no relationship to the citation and use of these measures. However, elements of these measures might be more useful than others, depending on the age-specific use and primary quality concerns. LIMITATIONS: Some of the information on the minimum standards of the 18 measures cannot be found in the existing literature. Measures published without English abstract were not searched. CONCLUSIONS: The quality of these measures is suboptimal. Researchers and practitioners in this field should exercise caution when choosing and using these measures. Efforts at improving the quality of the COHQoL measures, such as refining existing ones or developing new measures, are warranted. KNOWLEDGE TRANSFER STATEMENT: Researchers, clinician scientists, and clinicians can use the results of this study when deciding which oral health-related quality of life measure they wish to use in children.


Assuntos
Cárie Dentária , Qualidade de Vida , Adolescente , Criança , Pré-Escolar , Família , Humanos , Saúde Bucal
2.
Ned Tijdschr Tandheelkd ; 125(11): 593-601, 2018 11.
Artigo em Holandês | MEDLINE | ID: mdl-30457580

RESUMO

Evidence-based reviews of drugs causing medication-induced salivary gland dysfunction, such as xerostomia (sensation of oral dryness) and subjective sialorrhea are lacking. To compile a list of medicaments that influence salivary gland function, electronic databases were searched for relevant articles published up to June 2013. A total of 269 papers out of 3,867 records located satisfied the inclusion criteria (relevance, quality of methodology, strength of evidence). A total of 56 active substances with a higher level of evidence and 50 active substances with a moderate level of evidence of causing salivary gland dysfunction are described in this article. While xerostomia was a commonly reported outcome, the objective effect on salivary secretion was rarely measured. Xerostomia was, moreover, mostly reported as a negative side effect instead of the intended effect of that drug. A comprehensive list of medications having documented effects on salivary gland function or symptoms was compiled, which may assist practitioners in assessing patients who complain of dry mouth while taking medications.


Assuntos
Glândulas Salivares/efeitos dos fármacos , Xerostomia/etiologia , Humanos
3.
Eur J Endocrinol ; 179(4): R197-R206, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30299888

RESUMO

The differential diagnosis of differences or disorders of sex development (DSD) belongs to the most complex fields in medicine. It requires a multidisciplinary team conducting a synoptic and complementary approach consisting of thorough clinical, hormonal and genetic workups. This position paper of EU COST (European Cooperation in Science and Technology) Action BM1303 'DSDnet' was written by leading experts in the field and focuses on current best practice in genetic diagnosis in DSD patients. Ascertainment of the karyotpye defines one of the three major diagnostic DSD subclasses and is therefore the mandatory initial step. Subsequently, further analyses comprise molecular studies of monogenic DSD causes or analysis of copy number variations (CNV) or both. Panels of candidate genes provide rapid and reliable results. Whole exome and genome sequencing (WES and WGS) represent valuable methodological developments that are currently in the transition from basic science to clinical routine service in the field of DSD. However, in addition to covering known DSD candidate genes, WES and WGS help to identify novel genetic causes for DSD. Diagnostic interpretation must be performed with utmost caution and needs careful scientific validation in each DSD case.


Assuntos
Transtornos do Desenvolvimento Sexual/diagnóstico , Sequenciamento do Exoma , Cariótipo , Sequenciamento Completo do Genoma , Hiperplasia Suprarrenal Congênita/diagnóstico , Hiperplasia Suprarrenal Congênita/genética , Variações do Número de Cópias de DNA , Transtornos do Desenvolvimento Sexual/genética , União Europeia , Disgenesia Gonadal/diagnóstico , Disgenesia Gonadal/genética , Humanos , Biologia Molecular , Técnicas de Diagnóstico Molecular , Guias de Prática Clínica como Assunto , Análise de Sequência de DNA
4.
Hum Reprod ; 32(10): 2130-2137, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28938747

RESUMO

STUDY QUESTION: What is the likelihood of identifying genetic or endocrine abnormalities in a group of boys with 46, XY who present to a specialist clinic with a suspected disorder of sex development (DSD)? SUMMARY ANSWER: An endocrine abnormality of the gonadal axis may be present in a quarter of cases and copy number variants (CNVs) or single gene variants may be present in about half of the cases. WHAT IS KNOWN ALREADY: Evaluation of 46, XY DSD requires a combination of endocrine and genetic tests but the prevalence of these abnormalities in a sufficiently large group of boys presenting to one specialist multidisciplinary service is unclear. STUDY, DESIGN, SIZE, DURATION: This study was a retrospective review of investigations performed on 122 boys. PARTICIPANTS/MATERIALS, SETTING, METHODS: All boys who attended the Glasgow DSD clinic, between 2010 and 2015 were included in the study. The median external masculinization score (EMS) of this group was 9 (range 1-11). Details of phenotype, endocrine and genetic investigations were obtained from case records. MAIN RESULTS AND THE ROLE OF CHANCE: An endocrine abnormality of gonadal function was present in 28 (23%) with a median EMS of 8.3 (1-10.5) whilst the median EMS of boys with normal endocrine investigations was 9 (1.5-11) (P = 0.03). Endocrine abnormalities included a disorder of gonadal development in 19 (16%), LH deficiency in 5 (4%) and a disorder of androgen synthesis in 4 (3%) boys. Of 43 cases who had array-comparative genomic hybridization (array-CGH), CNVs were reported in 13 (30%) with a median EMS of 8.5 (1.5-11). Candidate gene analysis using a limited seven-gene panel in 64 boys identified variants in 9 (14%) with a median EMS of 8 (1-9). Of the 21 boys with a genetic abnormality, 11 (52%) had normal endocrine investigations. LIMITATIONS, REASONS FOR CAUTION: A selection bias for performing array-CGH in cases with multiple congenital malformations may have led to a high yield of CNVs. It is also possible that the yield of single gene variants may have been higher than reported if the investigators had used a more extended gene panel. WIDER IMPLICATIONS OF THE FINDINGS: The lack of a clear association between the extent of under-masculinization and presence of endocrine and genetic abnormalities suggests a role for parallel endocrine and genetic investigations in cases of suspected XY DSD. STUDY FUNDING/COMPETING INTEREST(S): RN was supported by the James Paterson Bursary and the Glasgow Children's Hospital Charity Summer Scholarship. SFA, RM and EST are supported by a Scottish Executive Health Department grant 74250/1 for the Scottish Genomes Partnership. EST is also supported by MRC/EPSRC Molecular Pathology Node and Wellcome Trust ISSF funding. There are no conflicts of interest. TRIAL REGISTRATION NUMBER: None.


Assuntos
Transtorno 46,XY do Desenvolvimento Sexual/diagnóstico , Testes Genéticos/métodos , Hormônios Esteroides Gonadais/sangue , Biomarcadores/sangue , Criança , Pré-Escolar , Hibridização Genômica Comparativa , Transtorno 46,XY do Desenvolvimento Sexual/sangue , Transtorno 46,XY do Desenvolvimento Sexual/epidemiologia , Transtorno 46,XY do Desenvolvimento Sexual/genética , Genótipo , Humanos , Lactente , Masculino , Fenótipo , Prevalência , Estudos Retrospectivos
5.
Behav Processes ; 141(Pt 3): 284-290, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28216119

RESUMO

It is commonly assumed that cats actively avoid eliminated materials (especially in multi-cat homes), suggesting regular litter box cleaning as the best defense against out-of-box elimination. The relationship between previous use and litter box appeal to familiar subsequent users is currently unknown. The purpose of this study was to investigate the relationship between previous litter box use and the identity of the previous user, type of elimination, odor, and presence of physical/visual obstructions in a multi-cat household scenario. Cats preferred a clean litter box to a dirty one, but the identity of the previous user had no impact on preferences. While the presence of odor from urine and/or feces did not impact litter box preferences, the presence of odorless faux-urine and/or feces did - with the presence of faux-feces being preferred over faux-urine. Results suggest neither malodor nor chemical communication play a role in litter box preferences, and instead emphasize the importance of regular removal of physical/visual obstructions as the key factor in promoting proper litter box use.


Assuntos
Comportamento Animal/fisiologia , Gatos/psicologia , Defecação/fisiologia , Comportamento Social , Animais , Fezes , Feminino , Masculino , Odorantes
6.
Clin Genet ; 91(2): 157-162, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28127758

RESUMO

Disorders of sex development (DSD), are a group of rare congenital conditions. Unlike 46, XX DSD where the cause is usually clear, identification of a cause of XY DSD is often unclear and may be attributed to a disorder of gonadal development, androgen synthesis or androgen action. Reaching a firm diagnosis is challenging and requires expertise within a framework that abides by the highest standards of clinical care. Whilst conditions associated with altered sex development have improved our fundamental understanding of sex and gonadal development, it is debatable whether this improvement in our understanding has improved the lives of people with DSD. Thus, there is a need for more emphasis on showing that a firm diagnosis for conditions associated with DSD is associated with a change in clinical practice that benefits the patient. With the rapid advances in diagnostic technology, there is also a need for clearer guidance on the relative merits of biochemical vs genetic evaluation. The standardization and harmonization of complex genetic and biochemical analyses for rare conditions are issues that require further guidance and it is probably that international networks and registries for rare conditions will facilitate the development of this framework.


Assuntos
Transtornos do Desenvolvimento Sexual/diagnóstico , Transtornos do Desenvolvimento Sexual/genética , Gônadas/crescimento & desenvolvimento , Desenvolvimento Sexual/genética , Androgênios/genética , Transtornos do Desenvolvimento Sexual/patologia , Feminino , Humanos , Masculino
7.
Oral Dis ; 22(5): 365-82, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26602059

RESUMO

The aim of this paper was to perform a systematic review of the pathogenesis of medication-induced salivary gland dysfunction (MISGD). Review of the identified papers was based on the standards regarding the methodology for systematic reviews set forth by the World Workshop on Oral Medicine IV and the PRISMA statement. Eligible papers were assessed for both the degree and strength of relevance to the pathogenesis of MISGD as well as on the appropriateness of the study design and sample size. A total of 99 papers were retained for the final analysis. MISGD in human studies was generally reported as xerostomia (the sensation of oral dryness) without measurements of salivary secretion rate. Medications may act on the central nervous system (CNS) and/or at the neuroglandular junction on muscarinic, α-and ß-adrenergic receptors and certain peptidergic receptors. The types of medications that were most commonly implicated for inducing salivary gland dysfunction were those acting on the nervous, cardiovascular, genitourinary, musculoskeletal, respiratory, and alimentary systems. Although many medications may affect the salivary flow rate and composition, most of the studies considered only xerostomia. Thus, further human studies are necessary to improve our understanding of the association between MISGD and the underlying pathophysiology.


Assuntos
Doenças das Glândulas Salivares/induzido quimicamente , Glândulas Salivares/efeitos dos fármacos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Medicina Bucal/métodos , Doenças das Glândulas Salivares/patologia , Glândulas Salivares/patologia
8.
Saudi Dent J ; 27(4): 171-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26644751

RESUMO

The aims of this paper are three-fold: (1) to summarize the current epidemiological data on oral cancer in Libya as reported in the published literature and as compared to other national oral cancer rates in the region; (2) to present both the history of the early development, and future goals, of population-based oral cancer tumor registries in Libya as they partner with the more established regional and international population-based cancer tumor registries; and, (3) to offer recommendations that will likely be required in the near future if these nascent, population-based Libyan oral cancer registries are to establish themselves as on-going registries for describing the oral cancer disease patterns and risk factors in Libya as well as for prevention and treatment. This comprehensive literature review revealed that the current baseline incidence of oral cancer in Libya is similar to those of other North Africa countries and China, but is relatively low compared to the United Kingdom, the United States, and India. The recently established Libyan National Cancer Registry Program, initiated in 2007, while envisioning five cooperating regional cancer registries, continues to operate at a relatively suboptimal level. Lack of adequate levels of national funding continue to plague its development…and the accompanying quality of service that could be provided to the Libyan people.

9.
Oral Surg Oral Med Oral Pathol Oral Radiol ; 120(2): 161-71.e20, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25953640

RESUMO

OBJECTIVE: To determine the efficacy and safety of interventions for mucous membrane pemphigoid (MMP). STUDY DESIGN: We conducted a systematic review from 2003 to 2013 according to the Cochrane Collaboration methodology. Randomized controlled trials (RCTs) or controlled clinical trials and observational studies were included, with diagnosis confirmed by clinical, histopathologic, and immunofluorescence criteria. The primary outcome was lesion remission or healing; several relevant secondary outcomes were also included. RESULTS: In the final analysis, 1 RCT and 32 observational studies were included. The one included RCT with a high risk of bias in multiple domains found limited evidence that pentoxifylline, combined with corticosteroid and cyclophosphamide, was more effective than standard therapy (corticosteroid + cyclophosphamide alone) for ocular MMP. We summarize here the outcomes from 32 observational studies examining 242 patients across 19 unique treatments. Interventions that show promise include rituximab and intravenous immunoglobulin. CONCLUSIONS: This systematic review is the most recent since 2003-2009. There is still lack of high-quality research providing evidence-based MMP treatments.


Assuntos
Penfigoide Mucomembranoso Benigno/tratamento farmacológico , Anti-Infecciosos/uso terapêutico , Ciclofosfamida/uso terapêutico , Dapsona/uso terapêutico , Glucocorticoides/uso terapêutico , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Imunossupressores/uso terapêutico , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
Oral Surg Oral Med Oral Pathol Oral Radiol ; 120(2): 132-42.e61, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25934414

RESUMO

OBJECTIVE: To determine the efficacy and safety of interventions for pemphigus vulgaris (PV). STUDY DESIGN: We conducted a systematic review from 2003 to 2013 according to the Cochrane Collaboration methodology. Randomized controlled trials (RCTs) or controlled clinical trials (CCTs) and observational studies were conducted along with diagnosis confirmed by clinical, histopathologic, and immunofluorescence criteria. Primary outcomes were disease remission and mortality; several relevant secondary outcomes were also included. RESULTS: Fourteen RCTs or CCTs and 110 observational studies were included in the final analyses. RCTs or CCTs demonstrated considerable heterogeneity in outcome measures, and all had a high risk of bias for at least 1 of 8 domains. Of the studies, 96.8% (120) described the use of oral corticosteroids. Azathioprine and mycophenolate-mofetil were the most commonly cited treatments. An increasing number of studies described biologic therapies (rituximab, intravenous immunoglobulin [IVIg]). Evidence supporting recent comprehensive treatment guidelines was reviewed. CONCLUSIONS: We found persisting wide variations in treatment practice and inadequate quality of research supporting optimal PV treatment.


Assuntos
Doenças da Boca/tratamento farmacológico , Pênfigo/tratamento farmacológico , Humanos , Doenças da Boca/diagnóstico , Doenças da Boca/epidemiologia , Pênfigo/diagnóstico , Pênfigo/epidemiologia , Indução de Remissão
11.
Arch Oral Biol ; 60(6): 863-74, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25841068

RESUMO

This narrative review of the functions of saliva was conducted in the PubMed, Embase and Web of Science databases. Additional references relevant to the topic were used, as our key words did not generate references which covered all known functions of saliva. These functions include maintaining a moist oral mucosa which is less susceptible to abrasion, and removal of micro-organisms, desquamated epithelial cells, leucocytes and food debris by swallowing. The mucins form a slimy coating on all surfaces in the mouth and act as a lubricant during such processes as mastication, formation of a food bolus, swallowing and speaking. Saliva provides the fluid in which solid tastants may dissolve and distributes tastants around the mouth to the locations of the taste buds. The hypotonic unstimulated saliva facilitates taste recognition. Salivary amylase is involved in digestion of starches. Saliva acts as a buffer to protect oral, pharyngeal and oesophageal mucosae from orally ingested acid or acid regurgitated from the stomach. Saliva protects the teeth against acid by contributing to the acquired enamel pellicle, which forms a renewable lubricant between opposing tooth surfaces, by being supersaturated with respect to tooth mineral, by containing bicarbonate as a buffer and urea and by facilitating clearance of acidic materials from the mouth. Saliva contains many antibacterial, antiviral and antifungal agents which modulate the oral microbial flora in different ways. Saliva also facilitates the healing of oral wounds. Clearly, saliva has many functions which are needed for proper protection and functioning of the human body.


Assuntos
Saliva/fisiologia , Cariogênicos , Humanos , Lubrificação , Mucosa Bucal/fisiologia , Percepção Olfatória/fisiologia , Saliva/química , Saliva/metabolismo , Proteínas e Peptídeos Salivares/fisiologia , Taxa Secretória , Percepção Gustatória/fisiologia , Doenças Dentárias/prevenção & controle , Cicatrização/fisiologia
12.
J Sound Vib ; 332(17): 3909-3923, 2013 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-24031098

RESUMO

The method of tailored Green's functions advocated by Doak (Proceedings of the Royal Society A254 (1960) 129 - 145.) for the solution of aeroacoustic problems is used to analyse the contribution of the mucosal wave to self-sustained modulation of air flow through the glottis during the production of voiced speech. The amplitude and phase of the aerodynamic surface force that maintains vocal fold vibration are governed by flow separation from the region of minimum cross-sectional area of the glottis, which moves back and forth along its effective length accompanying the mucosal wave peak. The correct phasing is achieved by asymmetric motion of this peak during the opening and closing phases of the glottis. Limit cycle calculations using experimental data of Berry et al. (Journal of the Acoustical Society of America 110 (2001) 2539 - 2547.) obtained using an excised canine hemilarynx indicate that the mechanism is robust enough to sustain oscillations over a wide range of voicing conditions.

13.
J Acoust Soc Am ; 133(4): 2340-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23556600

RESUMO

An investigation is made of the influence of subglottal boundary conditions on the prediction of voiced sounds. It is generally assumed in mathematical models of voicing that vibrations of the vocal folds are maintained by a constant subglottal mean pressure pI, whereas voicing is actually initiated by contraction of the chest cavity until the subglottal pressure becomes large enough to separate the vocal folds. The problem is reformulated to determine voicing characteristics in terms of a prescribed volumetric flow rate Qo of air from the lungs-the evolution of the resulting time-dependent subglottal mean pressure p[overline]-(t) is then governed by glottal mechanics, the aeroacoustics of the vocal tract, and the influence of continued contraction of the lungs. The new problem is analyzed in detail for an idealized mechanical vocal system that permits precise specification of all boundary conditions. Predictions of the glottal volume velocity pulse shape are found to be in good general agreement with the traditional constant-pI theory when pI is set equal to the time averaged value of p[overline]-(t). But, in all cases examined the constant-pI approximation yields values of the mean flow rates Qo and sound pressure levels that are smaller by as much as 10%.


Assuntos
Glote/fisiologia , Pulmão/fisiologia , Fonação , Voz , Fenômenos Biomecânicos , Simulação por Computador , Humanos , Modelos Biológicos , Contração Muscular , Análise Numérica Assistida por Computador , Pressão , Músculos Respiratórios/fisiologia , Fatores de Tempo , Vibração
14.
J Acoust Soc Am ; 131(2): 1391-400, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22352512

RESUMO

The voice source is dominated by aeroacoustic sources downstream of the glottis. In this paper an investigation is made of the contribution to voiced speech of secondary sources within the glottis. The acoustic waveform is ultimately determined by the volume velocity of air at the glottis, which is controlled by vocal fold vibration, pressure forcing from the lungs, and unsteady backreactions from the sound and from the supraglottal air jet. The theory of aerodynamic sound is applied to study the influence on the fine details of the acoustic waveform of "potential flow" added-mass-type glottal sources, glottis friction, and vorticity either in the glottis-wall boundary layer or in the portion of the free jet shear layer within the glottis. These sources govern predominantly the high frequency content of the sound when the glottis is near closure. A detailed analysis performed for a canonical, cylindrical glottis of rectangular cross section indicates that glottis-interior boundary/shear layer vortex sources and the surface frictional source are of comparable importance; the influence of the potential flow source is about an order of magnitude smaller.


Assuntos
Glote/anatomia & histologia , Acústica da Fala , Voz/fisiologia , Feminino , Glote/fisiologia , Humanos , Masculino , Modelos Biológicos , Pressão , Reologia , Prega Vocal/anatomia & histologia , Prega Vocal/fisiologia
15.
J Fluid Mech ; 672: 428-450, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21666824

RESUMO

An analysis is made of the sound generated by the time-dependent throttling of a nominally steady stream of air through a small orifice into a flow-through resonant cavity. This is exemplified by the production of voiced speech, where air from the lungs enters the vocal tract through the glottis at a time variable volume flow rate Q(t) controlled by oscillations of the glottis cross-section. Voicing theory has hitherto determined Q from a heuristic, reduced complexity 'Fant' differential equation (G. Fant, Acoustic Theory of Speech Production, 1960). A new self-consistent, integro-differential form of this equation is derived in this paper using the theory of aerodynamic sound, with full account taken of the back-reaction of the resonant tract on the glottal flux Q. The theory involves an aeroacoustic Green's function (G) for flow-surface interactions in a time-dependent glottis, so making the problem non-self-adjoint. In complex problems of this type it is not usually possible to obtain G in an explicit analytic form. The principal objective of the paper is to show how the Fant equation can still be derived in such cases from a consideration of the equation of aerodynamic sound and from the adjoint of the equation governing G in the neighbourhood of the 'throttle'. The theory is illustrated by application to the canonical problem of throttled flow into a Helmholtz resonator.

16.
J Sound Vib ; 330(13): 3123-3140, 2011 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-21603054

RESUMO

An analysis is made of the fluid-structure interactions involved in the production of voiced speech. It is usual to avoid time consuming numerical simulations of the aeroacoustics of the vocal tract and glottis by the introduction of Fant's 'reduced complexity' equation for the glottis volume velocity Q (G. Fant, Acoustic Theory of Speech Production, Mouton, The Hague 1960). A systematic derivation is given of Fant's equation based on the nominally exact equations of aerodynamic sound. This can be done with a degree of approximation that depends only on the accuracy with which the time-varying flow geometry and surface-acoustic boundary conditions can be specified, and replaces Fant's original 'lumped element' heuristic approach. The method determines all of the effective 'source terms' governing Q. It is illustrated by consideration of a simplified model of the vocal system involving a self-sustaining single-mass model of the vocal folds, that uses free streamline theory to account for surface friction and flow separation within the glottis. Identification is made of a new source term associated with the unsteady vocal fold drag produced by their oscillatory motion transverse to the mean flow.

17.
Sex Dev ; 5(3): 103-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21474920

RESUMO

BACKGROUND: Although a karyotype represents the first objective evidence of investigating a case of suspected disorder of sex development (DSD), the factors that influence the clinician's decision to initiate investigations are unclear. METHODS: Cases of suspected DSD in Scotland were identified through the Scottish Genital Anomaly Network (SGAN) Register. The timing as well as other factors that influence the decision to perform a karyotype were subsequently studied. RESULTS: Out of the 572 cases on the register, 383 (67%) were classified as having a non-specific disorder of under-masculinisation. In 463 (81%) cases, the sex of rearing was male, in 71 (12%) female, and in 38 (7%) cases data regarding sex of rearing were unavailable. A karyotype was reported to have been performed in 153/572 (27%) cases. Infants in Scotland with suspected DSD are more likely to have a karyotype performed in the presence of a low external masculinisation score, bilateral impalpable testes, proximal hypospadias, or associated malformations. DISCUSSION: These data represent the first attempt at benchmarking the decision to check a karyotype and investigate infants with suspected DSD. Whilst this decision may be related to the complexity of the genital anomaly, there are other factors that may influence this decision, and these require further exploration through more rigorous systems for data collection.


Assuntos
Tomada de Decisões , Transtornos do Desenvolvimento Sexual/diagnóstico , Transtornos do Desenvolvimento Sexual/genética , Feminino , Testes Genéticos , Humanos , Recém-Nascido , Cariotipagem , Masculino , Triagem Neonatal
18.
Fluid Dyn Res ; 42(1): 15001, 2010 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-20419082

RESUMO

An analysis is made of the fluid-structure interactions necessary to support self-sustained oscillations of a single-mass mechanical model of the vocal folds subject to a nominally steady subglottal overpressure. The single-mass model of Fant and Flanagan is re-examined and an analytical representation of vortex shedding during 'voiced speech' is proposed that promotes cooperative, periodic excitation of the folds by the glottal flow. Positive feedback that sustains glottal oscillations is shown to occur during glottal contraction, when the flow separates from the 'trailing edge' of the glottis producing a low pressure 'suction' force that tends to pull the folds together. Details are worked out for flow that can be regarded as locally two-dimensional in the glottal region. Predictions of free-streamline theory are used to model the effects of quasi-static variations in the separation point on the glottal wall. Numerical predictions are presented to illustrate the waveform of the sound radiated towards the mouth from the glottis. The theory is easily modified to include feedback on the glottal flow of standing acoustic waves, both in the vocal tract beyond the glottis and in the subglottal region.

19.
J Fluids Struct ; 25(8): 1299-1317, 2009 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-20161450

RESUMO

An analysis is made of the nonlinear interactions between flow in the subglottal vocal tract and glottis, sound waves in the subglottal system and a mechanical model of the vocal folds. The mean flow through the system is produced by a nominally steady contraction of the lungs, and mechanical experiments frequently involve a 'lung cavity' coupled to an experimental subglottal tube of arbitrary or ill-defined effective length L, on the basis that the actual value of L has little or no influence on excitation of the vocal folds. A simple, self-exciting single mass mathematical model of the vocal folds is used to investigate the sound generated within the subglottal domain and the unsteady volume flux from the glottis for experiments where it is required to suppress feedback of sound from the supraglottal vocal tract. In experiments where the assumed absorption of sound within the sponge-like interior of the lungs is small, the influence of changes in L can be very significant: when the subglottal tube behaves as an open-ended resonator (when L is as large as half the acoustic wavelength) there is predicted to be a mild increase in volume flux magnitude and a small change in waveform. However, the strong appearance of second harmonics of the acoustic field is predicted at intermediate lengths, when L is roughly one quarter of the acoustic wavelength. In cases of large lung damping, however, only modest changes in the volume flux are predicted to occur with variations in L.

20.
Genome ; 49(7): 808-14, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16936789

RESUMO

In this report, we describe the cloning of a cDNA from the zebrafish Danio rerio encoding a protein containing a BTB-POZ domain closely resembling the BTBD1 and BTBD2 proteins previously identified in mammals. However, unlike other BTB-POZ-containing genes, expression of this gene in adults is most abundant in oocytes, where the RNA can be detected at all stages of oogenesis examined. The presence of the RNA persists through early cleavage, but is decreased significantly by gastrulation. Although the function of this gene has yet to be determined, its resemblance to the BTB-POZ family of genes coupled with its expression pattern suggests that it may have an important function in oogenesis and (or) early zebrafish development.


Assuntos
Oócitos/metabolismo , Proteínas de Peixe-Zebra/isolamento & purificação , Peixe-Zebra/metabolismo , Sequência de Aminoácidos , Animais , Proteínas de Transporte/genética , Clonagem Molecular , DNA Complementar/isolamento & purificação , Proteínas de Ligação a DNA/genética , Embrião não Mamífero/metabolismo , Feminino , Dados de Sequência Molecular , Oogênese , Especificidade de Órgãos , Estrutura Terciária de Proteína , RNA/biossíntese , Fatores de Transcrição/genética , Proteínas de Peixe-Zebra/biossíntese , Proteínas de Peixe-Zebra/genética
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