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1.
Plant J ; 111(4): 936-953, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35696314

RESUMEN

In a cross-continental research initiative, including researchers working in Australia and Denmark, and based on joint external funding by a 3-year grant from the Novo Nordisk Foundation, we have used DNA sequencing, extensive chemical profiling and molecular networking analyses across the entire Eremophila genus to provide new knowledge on the presence of natural products and their bioactivities using polypharmocological screens. Sesquiterpenoids, diterpenoids and dimers of branched-chain fatty acids with previously unknown chemical structures were identified. The collection of plant material from the Eremophila genus was carried out according to a 'bioprospecting agreement' with the Government of Western Australia. We recognize that several Eremophila species hold immense cultural significance to Australia's First Peoples. In spite of our best intentions to ensure that new knowledge gained about the genus Eremophila and any potential future benefits are shared in an equitable manner, in accordance with the Nagoya Protocol, we encounter serious dilemmas and potential conflicts in making benefit sharing with Australia's First Peoples a reality.


Asunto(s)
Diterpenos , Scrophulariaceae , Australia
2.
Plant J ; 108(2): 555-578, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34324744

RESUMEN

Eremophila is the largest genus in the plant tribe Myoporeae (Scrophulariaceae) and exhibits incredible morphological diversity across the Australian continent. The Australian Aboriginal Peoples recognize many Eremophila species as important sources of traditional medicine, the most frequently used plant parts being the leaves. Recent phylogenetic studies have revealed complex evolutionary relationships between Eremophila and related genera in the tribe. Unique and structurally diverse metabolites, particularly diterpenoids, are also a feature of plants in this group. To assess the full dimension of the chemical space of the tribe Myoporeae, we investigated the metabolite diversity in a chemo-evolutionary framework applying a combination of molecular phylogenetic and state-of-the-art computational metabolomics tools to build a dataset involving leaf samples from a total of 291 specimens of Eremophila and allied genera. The chemo-evolutionary relationships are expounded into a systematic context by integration of information about leaf morphology (resin and hairiness), environmental factors (pollination and geographical distribution), and medicinal properties (traditional medicinal uses and antibacterial studies), augmenting our understanding of complex interactions in biological systems.


Asunto(s)
Evolución Biológica , Eremophila (Planta)/química , Eremophila (Planta)/fisiología , Adaptación Biológica , Antibacterianos/química , Antibacterianos/farmacología , Australia , Diterpenos/química , Medicina Tradicional , Metabolómica/métodos , Myoporaceae/química , Myoporaceae/fisiología , Fitoquímicos/química , Fitoquímicos/farmacología , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Polinización , Resinas de Plantas/química
3.
J Phys Chem A ; 118(32): 6287-98, 2014 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-25051010

RESUMEN

Different classes of ground electronic state pairwise interatomic interactions are referenced to a single canonical potential using explicit transformations. These approaches have been applied to diatomic molecules N2, CO, H2(+), H2, HF, LiH, Mg2, Ca2, O2, the argon dimer, and one-dimensional cuts through multidimensional potentials of OC-HBr, OC-HF, OC-HCCH, OC-HCN, OC-HCl, OC-HI, OC-BrCl, and OC-Cl2 using accurate semiempirically determined interatomic Rydberg-Klein-Rees (RKR) and morphed intermolecular potentials. Different bonding categories are represented in these systems, which vary from van der Waals, halogen bonding, and hydrogen bonding to strongly bound covalent molecules with binding energies covering 3 orders of magnitude from 84.5 to 89,600.6 cm(-1) in ground state dissociation energies. Such approaches were then utilized to give a unified perspective on the nature of bonding in the whole range of diatomic and intermolecular interactions investigated.

4.
Future Healthc J ; 11(2): 100130, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38774033

RESUMEN

Air pollution (AP) significantly jeopardises health, with the Royal College of Physicians accepting the adverse effects of AP are not being sufficiently communicated to patients by healthcare professionals (HCP). To explore HCPs' understanding and attitudes toward AP and its health impacts, we conducted a service evaluation survey in a group of hospital doctors. A questionnaire comprising 20 questions about AP and its health associations was completed by 133 hospital doctors working at University Hospital Southampton NHS Foundation Trust, UK. While 65% (n = 86) of respondents strongly agreed that AP is relevant to health, 79% (n = 105) felt insufficiently trained on AP and its health associations. The survey shows that HCPs' knowledge of AP and its connection to poor health is a major barrier in discussions with patients. Further research is needed to understand whether these views are nationally shared among HCPs and to explore the most effective strategies for enhancing AP awareness.

5.
Theor Appl Genet ; 126(2): 511-22, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23086512

RESUMEN

Selection for phomopsis stem blight disease (PSB) resistance is one of the key objectives in lupin (Lupinus angustifolius L.) breeding programs. A cross was made between cultivar Tanjil (resistant to PSB) and Unicrop (susceptible). The progeny was advanced into F(8) recombinant inbred lines (RILs). The RIL population was phenotyped for PSB disease resistance. Twenty plants from the RIL population representing disease resistance and susceptibility was subjected to next-generation sequencing (NGS)-based restriction site-associated DNA sequencing on the NGS platform Solexa HiSeq2000, which generated 7,241 single nucleotide polymorphisms (SNPs). Thirty-three SNP markers showed the correlation between the marker genotypes and the PSB disease phenotype on the 20 representative plants, which were considered as candidate markers linked to a putative R gene for PSB resistance. Seven candidate markers were converted into sequence-specific PCR markers, which were designated as PhtjM1, PhtjM2, PhtjM3, PhtjM4, PhtjM5, PhtjM6 and PhtjM7. Linkage analysis of the disease phenotyping data and marker genotyping data on a F(8) population containing 187 RILs confirmed that all the seven converted markers were associated with the putative R gene within the genetic distance of 2.1 CentiMorgan (cM). One of the PCR markers, PhtjM3, co-segregated with the R gene. The seven established PCR markers were tested in the 26 historical and current commercial cultivars released in Australia. The numbers of "false positives" (showing the resistance marker allele band but lack of the putative R gene) for each of the seven PCR markers ranged from nil to eight. Markers PhtjM4 and PhtjM7 are recommended in marker-assisted selection for PSB resistance in the Australian national lupin breeding program due to its wide applicability on breeding germplasm and close linkage to the putative R gene. The results demonstrated that application of NGS technology is a rapid and cost-effective approach in development of markers for molecular plant breeding.


Asunto(s)
Ascomicetos/fisiología , Resistencia a la Enfermedad/genética , Genes de Plantas/genética , Marcadores Genéticos , Secuenciación de Nucleótidos de Alto Rendimiento , Lupinus/genética , Enfermedades de las Plantas/genética , Tallos de la Planta/genética , Ascomicetos/patogenicidad , Secuencia de Bases , Mapeo Cromosómico , Cromosomas de las Plantas/genética , Cruzamientos Genéticos , Ligamiento Genético/genética , Lupinus/inmunología , Lupinus/microbiología , Datos de Secuencia Molecular , Fenotipo , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/microbiología , Tallos de la Planta/inmunología , Tallos de la Planta/microbiología , Reacción en Cadena de la Polimerasa , Polimorfismo de Nucleótido Simple/genética , Sitios de Carácter Cuantitativo
6.
Cytopathology ; 23(6): 371-7, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21749501

RESUMEN

OBJECTIVE: To review the risk of pre-invasive and invasive gynaecological pathology in women referred with cervical cytology reporting ?glandular neoplasia. METHODS: Review of the case notes of all women referred with cervical cytology reported as ?glandular neoplasia between January 1999 and December 2008 at two UK hospitals: Portsmouth Hospitals NHS Trust and Queen Mary's Hospital Sidcup. The category of 'borderline nuclear change in endocervical cells', result code 8 according to the national health service cancer screening programme (NHSCSP), was excluded from the study. RESULTS: A total of 200 women were identified using the hospitals' pathology computer systems. Invasive carcinoma was found in 48 women (24%): 28 endocervical adenocarcinomas, eight squamous cell carcinomas (SCC), ten endometrial and two ovarian adenocarcinomas. Pre-invasive neoplasia was found in 115 (57.5%), including 14 cervical glandular intraepithelial neoplasia (CGIN), 31 cervical intraepithelial neoplasia (CIN) grade 2/3 and 70 concomitant CGIN and CIN2/3. CIN1/HPV was found in 25, simple endometrial hyperplasia in three and no histological abnormality in three. Thirty-four (70.8%) of 48 invasive carcinomas (of which 23 were endocervical adenocarcinomas) were in asymptomatic women investigated for abnormal cytology. Fourteen of 34 (41.4%) of those with ?glandular neoplasia thought to be endometrial were CGIN or CIN2/3. Colposcopic appearances were normal in 47.6% of women with pure cervical glandular neoplasia (adenocarcinoma or CGIN) compared with 12.8% with squamous cell lesions (CIN2/3 or SCC): P = 0.0001. Thus, colposcopy was more sensitive for detecting squamous cell abnormalities than their glandular counterparts. Although cervical adenocarcinomas are less amenable to prevention by screening than cervical SCC, in our study cervical cytology predominantly detected these abnormalities at their early asymptomatic stages. CONCLUSION: At least CIN2 was found in 81.5% in women referred with cervical cytology reporting ?glandular neoplasia. A thorough evaluation of the whole genital tract is needed if colposcopy is negative.


Asunto(s)
Cuello del Útero/patología , Técnicas Citológicas/métodos , Neoplasias Glandulares y Epiteliales/patología , Neoplasias del Cuello Uterino/patología , Adulto , Colposcopía , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Glandulares y Epiteliales/diagnóstico , Factores de Riesgo , Reino Unido , Neoplasias del Cuello Uterino/diagnóstico
7.
J Chem Phys ; 134(6): 064317, 2011 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-21322690

RESUMEN

The HI homodimer was found to have structural and vibrational properties unlike any other previously studied (HX)(2) system, with X = F, Cl, and Br. The infrared spectrum of (HI)(2) is also observed to be distinctly different from the other members of the series. In addition, the interaction energy of the (HI)(2) dimer has been calculated using the coupled-cluster with singles, doubles, and perturbative triples [CCSD(T)] level of theory. A four-dimensional morphed intermolecular potential has been generated and then morphed using available near infrared and submillimeter spectroscopic data recorded in supersonic jet expansions. The morphed potential is found to have a single global minimum with a symmetric structure having C(2h) symmetry. The equilibrium dissociation energy is found to be 359 cm(-1) with the geometry in Jacobi coordinates of R(e) = 4.35 Å, θ(1) = 43°, θ(2) = 137°, and φ = 180°. The infrared spectrum is characterized by pairs of excited vibrational states resulting from the coupling of the two HI stretching modes. A qualitative model using a quadratic approximation has been fitted to obtain an estimate of this coupling. Furthermore, a morphed intermolecular potential for the vibrationally excited system was also obtained that gives a quantitative estimate of the shift in the potential due to the excitation. The submillimeter analysis is consistent with a ground state having its highest probability as a paired hydrogen bond configuration with R(0) = 4.56372(1) Å and an average angle θ=cos(-1)((1/2)) = 46.40(1)° (between the diatom center of mass∕center of mass axis and direction of each component hydrogen iodide molecule). On monodeuteration, however, the ground state is predicted to undergo an anomalous structural isotope change to an L-shaped HI-DI structure with highest probability at R(0) = 4.51 Å, θ(1) = 83°, θ(2) = 177°, and φ = 180°. These results provide a test for large scale ab initio calculations and have implications for the interpretation of photoinduced chemistry and other properties of the dimer.


Asunto(s)
Ácidos/química , Compuestos de Yodo/química , Ácido Clorhídrico , Enlace de Hidrógeno , Teoría Cuántica
8.
Science ; 204(4393): 635-7, 1979 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-432670

RESUMEN

The vascular smooth muscle of cerebral blood vessels is relatively insensitive to sympathomimetic stimulation compared with muscle from systemic vessels. The transition in the vertebral artery occurs just rostral to the emergence of that artery from the foramen of the lateral process of the atlas and in the internal carotid artery just before it enters the carotid canal. These sites in the adult correspond to embryological junctions between segments of the vertebral and internal carotid arteries derived from the primitive dorsal aortas and their branches with vessels originating locally from the bilateral longitudinal neural arteries. Topographic patterns of vascular properties may in some cases be explained by the different sites of origin of their primordial mesodermal cells.


Asunto(s)
Arteria Carótida Interna/inervación , Norepinefrina/farmacología , Arteria Vertebral/inervación , Fibras Adrenérgicas/embriología , Animales , Arteria Carótida Interna/embriología , Arterias Cerebrales/embriología , Arterias Cerebrales/inervación , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Músculo Liso/inervación , Conejos , Arteria Vertebral/embriología
9.
Science ; 173(3994): 336-8, 1971 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-4327032

RESUMEN

The isolated taenia coli of the guinea pig takes up tritiated adenosine, adenosine monophosphate, adenosine diphosphate, and adenosine triphosphate, in preference to tritiated inosine and adenine. After uptake, [(3)H]adenosine is converted and retained primarily as [(3)H]adenosine triphosphate. Tritium is released from taenia coli treated with [(3)H]adenosine upon activation of the nonadrenergic inhibitory nerves. These results are consistent with the previous evidence that adenosine triphosphate may be the transmitter from the nerves.


Asunto(s)
Nucleótidos de Adenina/análisis , Adenosina Trifosfato/metabolismo , Plexo Mientérico/fisiología , Tritio/análisis , Nucleótidos de Adenina/metabolismo , Adenosina Trifosfato/biosíntesis , Adenosina Trifosfato/fisiología , Animales , Colon/efectos de los fármacos , Colon/inervación , Colon/metabolismo , AMP Cíclico/metabolismo , Estimulación Eléctrica , Cobayas , Nucleósidos/farmacología , Factores de Tiempo
10.
Science ; 207(4434): 1001-2, 1980 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-7352293

RESUMEN

Intrinsic myogenic tone in the buccal segment of the rabbit facial vein is exquisitely sensitive to small changes in temperature in the range 33 degrees to 44 degrees C. This particular venous segment also exhibits a preponderance of beta-adrenergic receptors and receives a dense, medial sympathetic innervation. This area of the vein is proposed to act as a temperature-sensitive sphincter that distributes cooled nasal venous blood between superficial and deep venous drainage systems in the head and neck. Deviation of cool blood to deeper venous sinuses has been shown to be an important thermoregulatory mechanism.


Asunto(s)
Regulación de la Temperatura Corporal , Cara/irrigación sanguínea , Conejos/fisiología , Vasoconstricción , Venas/fisiología , Animales , Encéfalo/irrigación sanguínea , Encéfalo/fisiología , Contracción Muscular , Temperatura , Sistema Vasomotor/fisiología , Venas/anatomía & histología
11.
Science ; 234(4773): 196-7, 1986 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-3018932

RESUMEN

Vascular smooth muscle from different arteries of the rabbit varies in sensitivity to norepinephrine, even when factors known to contribute to this variation are excluded. Sensitivity to norepinephrine mediated through the alpha-adrenoceptor is linearly related to the agonist dissociation constant, but is not significantly related to receptor reserve. These results suggest that agonist affinity is the primary determinant of sensitivity to norepinephrine, at least in these arteries, and that this is a locally regulated characteristic which may account for regional sensitivity changes.


Asunto(s)
Músculo Liso Vascular/efectos de los fármacos , Norepinefrina/farmacología , Receptores Adrenérgicos alfa/metabolismo , Animales , Arterias , Contracción Muscular/efectos de los fármacos , Músculo Liso Vascular/fisiología , Conejos
13.
J Small Anim Pract ; 60(1): 51-57, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30294790

RESUMEN

OBJECTIVES: To compare the short-term complications of unilateral versus single-session bilateral medial patellar luxation surgery in small dogs. MATERIALS AND METHODS: The medical records of dogs weighing less than 13∙6 kg that underwent medial patellar luxation surgery were reviewed. Dogs were included in one of two groups based on the type of surgery performed (unilateral or single-session bilateral). Postoperative patellar luxation grade and complications were compared between the groups. RESULTS: Two hundred and fifty-one dogs were included. In the bilateral treatment group, there was less improvement in patellar luxation grade and postoperative medial patellar luxation grade was higher. The frequency of major complications was higher in the bilateral group (23%) compared with the unilateral group (12%). CLINICAL SIGNIFICANCE: Single-session bilateral medial patellar luxation surgery was associated with a higher complication rate compared to unilateral surgery in this non-randomised observational study. Staged rather than single-session bilateral surgery should be considered in dogs with bilateral medial patellar luxation to improve clinical outcome and reduce the chance of major complications.


Asunto(s)
Enfermedades de los Perros/cirugía , Luxación de la Rótula/veterinaria , Complicaciones Posoperatorias/veterinaria , Animales , Perros , Femenino , Masculino , Luxación de la Rótula/cirugía , Estudios Retrospectivos , Resultado del Tratamiento
14.
Endocr Rev ; 13(2): 220-40, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1352243

RESUMEN

The primary aim of this review has been to clarify the tumor shrinking effects of dopamine agonists on pituitary macroadenomas of different cell types. Shrinkage is most dramatic for macroprolactinomas and is due to cell size reduction. Seventy-nine percent of 271 definite macroprolactinomas were reduced in size by at least 25%, and 89% shrank to some degree. Most shrinkage occurs during the first 3 months of treatment, although in a minority shrinkage is delayed. Dopamine agonist resistance during long-term therapy is exceptional. Drug withdrawal nearly always leads to a return of hyperprolactinemia, even after several years treatment, although early tumor reexpansion is unusual. About 10% of true macroprolactinomas do not shrink with dopamine agonists; the molecular mechanisms of such resistance have yet to be determined. Alternative formulations of BC and new dopamine agonists (CV 205-502 and cabergoline) are useful for the minority of patients unable to tolerate oral BC, but do not seem to further improve overall shrinkage rates. The risks of pregnancy have probably been overstated, and BC is suitable primary treatment for women with prolactinomas of all sizes; the drug can be used safely during pregnancy in the event of clinically relevant tumor expansion. The interpretation of different degrees of hyperprolactinemia is discussed and management strategies suggested. Most patients with macroprolactinomas now avoid surgery, but drug-induced, time-dependent tumor fibrosis should be remembered if surgery is contemplated. Nonfunctioning pituitary tumors are mostly of gonadotroph cell origin and may be associated with significant disconnection hyperprolactinaemia. Seventy-six of 84 well-characterized tumors showed no tumor shrinkage during dopamine agonist therapy. Possible explanations include abnormalities of dopamine receptor number and function. Preliminary evidence suggests that dopamine agonists may restrain the growth of some functionless tumors; most of these tumors, however, can be satisfactorily debulked using transsphenoidal surgery. In contrast to macroprolactinomas, other functioning pituitary tumors (GH-, TSH-, and ACTH-secreting) rarely shrink during dopamine agonist therapy, although the number of tumors studied is small.


Asunto(s)
Adenoma/tratamiento farmacológico , Dopaminérgicos/uso terapéutico , Neoplasias Hipofisarias/tratamiento farmacológico , Complicaciones Neoplásicas del Embarazo/tratamiento farmacológico , Prolactinoma/tratamiento farmacológico , Adenoma/metabolismo , Adenoma/patología , Bromocriptina/uso terapéutico , División Celular , Femenino , Humanos , Masculino , Metaanálisis como Asunto , Neoplasias Hipofisarias/metabolismo , Embarazo , Complicaciones Neoplásicas del Embarazo/metabolismo , Complicaciones Neoplásicas del Embarazo/patología , Prolactina/sangre , Prolactinoma/metabolismo , Prolactinoma/patología
15.
Clin Endocrinol (Oxf) ; 68(3): 343-9, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17892497

RESUMEN

OBJECTIVE: The introduction of ready-to-use lanreotide Autogel has presented the possibility of patients receiving their acromegaly treatment at home. The objective of this study was to assess the ability of patients (or their partners) to administer repeat, unsupervised, injections of lanreotide Autogel without compromising efficacy or safety. DESIGN: Multicentre (10 UK regional endocrine centres), open-label, nonrandomised, controlled study. Patients elected either to receive/administer unsupervised home injections after injection technique training (Test group) or continued to receive injections from a healthcare professional (Control group). Patients received monthly injections of lanreotide Autogel at their established dose. Effects were monitored for up to 40 weeks. PATIENTS: Thirty patients (15 per treatment group) with acromegaly treated with a stable dose of lanreotide Autogel (60, 90 or 120 mg) for > or = 4 months before screening. Measurements The main outcome measure was the proportion of patients/partners who successfully administered injections throughout the study. RESULTS: All Test group patients/partners qualified to administer injections. Fourteen of 15 patients fulfilled all criteria for successful administration of unsupervised injections (95% confidence interval, 70%-99%). Fourteen of 15 Test and 14/15 Control patients maintained growth hormone and IGF-1 control. Local injection tolerability was good for both treatment groups, and safety profiles were similar. All Test group patients continued with unsupervised injections after the study. CONCLUSIONS: Patients with acromegaly or their partners were able to administer lanreotide Autogel injections with no detrimental effect on efficacy and safety; therefore, unsupervised home injections are a viable alternative to healthcare professional injections for suitably motivated patients.


Asunto(s)
Acromegalia/tratamiento farmacológico , Atención Domiciliaria de Salud , Péptidos Cíclicos/administración & dosificación , Autocuidado , Somatostatina/análogos & derivados , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Inyecciones Subcutáneas , Masculino , Persona de Mediana Edad , Somatostatina/administración & dosificación , Resultado del Tratamiento
17.
Artículo en Inglés | MEDLINE | ID: mdl-26985190

RESUMEN

BACKGROUND: Adolescents with childhood onset growth hormone deficiency (CO-GHD) require re-evaluation of their growth hormone (GH) axis on attainment of final height to determine eligibility for adult GH therapy (rhGH). AIM: Retrospective multicentre review of management of young adults with CO-GHD in four paediatric centres in Scotland during transition. PATIENTS: Medical records of 130 eligible CO-GHD adolescents (78 males), who attained final height between 2005 and 2013 were reviewed. Median (range) age at initial diagnosis of CO-GHD was 10.7 years (0.1-16.4) with a stimulated GH peak of 2.3 µg/l (0.1-6.5). Median age at initiation of rhGH was 10.8 years (0.4-17.0). RESULTS: Of the 130 CO-GHD adolescents, 74/130(57 %) had GH axis re-evaluation by stimulation tests /IGF-1 measurements. Of those, 61/74 (82 %) remained GHD with 51/74 (69 %) restarting adult rhGH. Predictors of persistent GHD included an organic hypothalamic-pituitary disorder and multiple pituitary hormone deficiencies (MPHD). Of the remaining 56/130 (43 %) patients who were not re-tested, 34/56 (61 %) were transferred to adult services on rhGH without biochemical retesting and 32/34 of these had MPHD. The proportion of adults who were offered rhGH without biochemical re-testing in the four centres ranged between 10 and 50 % of their total cohort. CONCLUSIONS: A substantial proportion of adults with CO-GHD remain GHD, particularly those with MPHD and most opt for treatment with rhGH. Despite clinical guidelines, there is significant variation in the management of CO-GHD in young adulthood across Scotland.

18.
Trends Endocrinol Metab ; 1(2): 95-8, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-18411098

RESUMEN

Growth within the anterior pituitary gland is probably controlled by several interacting extracellular messenger molecules, including hypothalamic peptides, target gland hormones, and several growth factors acting in autocrine or paracrine fashion. Adenoma formation may result from abnormal production of such factors or their specific cellular receptors, loss of local inhibitory influences, activation of the intracellular secondary message pathways conveying the mitogenic signal to the nucleus, or deregulation of the nuclear processes controlling mitosis.

19.
Cochrane Database Syst Rev ; (2): CD003420, 2005 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-15846664

RESUMEN

BACKGROUND: Antithyroid drugs are widely used in the therapy of hyperthyroidism. There are wide variations in the dose, regimen or duration of treatment used by health professionals. OBJECTIVES: To assess the effects of dose, regimen and duration of antithyroid drug therapy for Graves' hyperthyroidism. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (Central), MEDLINE, EMBASE, BIOSIS, CINAHL, HEALTHSTAR, Current Controlled Trials and reference lists. We contacted investigators and hand searched conference abstracts. Most recent search: July 2004. SELECTION CRITERIA: Randomised and quasi-randomised trials of antithyroid medication for Graves' hyperthyroidism were used. DATA COLLECTION AND ANALYSIS: Trial allocation to included, excluded and awaiting assessment categories was made by consensus. Two reviewers independently extracted data and assessed trial quality. Pooling of data for primary outcomes, and select exploratory analyses were undertaken. MAIN RESULTS: Twenty-three randomised trials involving 3115 participants were included. Overall the quality of trials as reported was poor; specifically in terms of allocation concealment, assessor blinding and loss to follow-up. Four trials examined the effect of duration of therapy on relapse rates of Graves' hyperthyroidism. In one trial using the Titration regimen, longer duration therapy (18 months) had significantly fewer relapses (37% versus 58%) than six month therapy (Odds ratio (OR) 0.42, 95% confidence interval (CI) 0.18 to 0.96). In one quasi-randomised trial using the Block-Replace regimen, there was no significant difference between the six and 12 month (relapses rates 41% versus 35%) arms of the study. Extending the duration of therapy to over 18 months was not associated with improved relapse rates (Peto OR 0.75, 95% CI 0.39 to 1.43). Twelve trials examined the effect of Block-Replace versus Titration regimen. The relapse rates were similar in both groups at 51% in the Block-Replace group and 54% in the Titration group (Peto OR 0.86, 95% CI 0.68 to 1.08). Participants reporting rashes (10% versus 5%) and withdrawing due to side effects (16% versus 9%) were significantly higher in the Block-Replace group compared to the Titration group respectively. Three studies considered the addition of thyroxine with continued low dose antithyroid therapy after initial therapy with antithyroid drugs. There was significant heterogeneity between the studies and the difference between the two groups were not significant (Odds ratio 0.58, 95% CI 0.05 to 6.21). Four studies considered the addition of thyroxine alone after initial therapy with antithyroid drugs. There was no significant difference in the relapse rates between the groups after 12 months follow-up with relapse rates being 31% (88/282) with thyroxine and 29% (82/284) with placebo (Peto OR 1.15, 95% CI 0.79 to 1.67). AUTHORS' CONCLUSIONS: The evidence (based on four studies) suggests that the optimal duration of antithyroid drug therapy for the Titration regimen is 12 to 18 months. The six month Block-Replace regimen was found to be as effective as the 12 month treatment in one quasi-randomised study. The Titration (low dose) regimen had fewer adverse effects than the Block-Replace (high dose) regimen and was no less effective in trials (based on 12 trials) of equal duration. Continued thyroxine treatment following initial antithyroid therapy does not appear to provide any benefit in terms of recurrence of hyperthyroidism. The incidence of hypothyroidism was not reported and there were no deaths reported in the study populations.


Asunto(s)
Antitiroideos/administración & dosificación , Enfermedad de Graves/tratamiento farmacológico , Esquema de Medicación , Femenino , Humanos , Hipertiroidismo/tratamiento farmacológico , Masculino , Ensayos Clínicos Controlados Aleatorios como Asunto , Tiroxina/administración & dosificación
20.
J Mech Behav Biomed Mater ; 50: 93-103, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26116957

RESUMEN

AIM: To investigate the effect of laboratory and clinical finishing procedures for zirconia on antagonistic enamel wear. MATERIALS AND METHODS: Forty-eight yttria-tetragonal partially stabilised zirconia (Y-TZP) specimens were prepared and divided into four groups according to their surface preparation: laboratory polished (LP); laboratory polished and glazed (G); clinically adjusted (CA); and clinically adjusted and repolished (CAR). Enamel opposing enamel was used as a control. Pre-testing surface roughness for each group was determined using contact profilometry. Two-body wear resistance tests were conducted using a masticatory simulator. Enamel specimens were subjected to 120,000 cycles in distilled water (frequency 1.6 Hz, loading force of 49 N). Volumetric and vertical enamel losses were measured by superimposition of pre- and post-testing images using a three-dimensional laser scanner and software analysis. Scanning electron microscopy was used for qualitative surface analysis of pre- and post-testing zirconia and enamel surfaces. One-way ANOVA and multiple comparisons with Bonferroni corrections were used for statistical analysis at a significance level of α=0.05. RESULTS: There was no statistical difference in volumetric and vertical enamel loss between CAR, G and LP. CAR produced statistically significantly less volumetric enamel loss compared with CA and control, and statistically significantly less vertical enamel loss compared with CA. Volumetric and vertical enamel loss were highly correlated in all groups. CONCLUSIONS: Enamel wear by clinically ground zirconia is comparable to that of opposing enamel surfaces and greater than clinically repolished zirconia. Repolishing of zirconia restorations following clinical adjustment with diamond burs is effective in reducing antagonistic enamel wear.


Asunto(s)
Esmalte Dental/efectos de los fármacos , Desgaste de los Dientes/inducido químicamente , Desgaste de los Dientes/prevención & control , Circonio/efectos adversos , Humanos , Laboratorios , Ensayo de Materiales , Fenómenos Mecánicos , Propiedades de Superficie
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