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1.
Eur J Prosthodont Restor Dent ; 29(1): 22-34, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-32780569

RESUMO

Scientific evidence regarding conditioning of different ceramic and hybrid materials and their bonding on titanium abutments is lacking. Titanium disks (Tritan) (N=450, n=15) were randomly cemented onto five different ceramic and hybrid materials, namely 1. Zenostar T, 2. Lava Ultimate, 3. IPS e.max CAD, 4. Vita Enamic multicolor and 5. G-ceram using three different cements, Panavia 21, TheraCem and Multilink hybrid abutment. Half of all specimens were thermocycled (5000 cycles, 5-55°C), while the other half were kept dry. Macro shear bond testing was conducted using a universal testing machine. Failure types were classified using a digital microscope. Data was statistically analyzed with three-way ANOVA and Tukey HSD post hoc tests. Both the ceramic (P⟨0.0001) and cement type(P⟨0.0001) significantly affected the shear bond strength(MPa), while thermocycling did not (P⟩0.05). The incidence of cohesive (50.34%) and adhesive failures (49.66%) were not significantly different. As for implant superstructures, when ceramics are bonded to titanium bases, the ceramic and cement type both have an impact on the bond strengths along with the conditioning and bonding protocols for each substrate. An equal affinity of the cements tested to the ceramic, hybrid materials and to titanium can be assumed. Combination of zirconia and TheraCem can be recommended for clinical use.


Assuntos
Colagem Dentária , Titânio , Cerâmica , Coroas , Porcelana Dentária , Análise do Estresse Dentário , Teste de Materiais , Cimentos de Resina , Propriedades de Superfície , Zircônio
2.
World J Surg ; 42(5): 1432-1439, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29484475

RESUMO

INTRODUCTION: Medullary thyroid cancer (MTC) is a rare tumour of neuroendocrine origin with a more aggressive profile than differentiated thyroid cancer. Familial cases of MTC are associated with RET mutations whilst RAS mutations appear to be a frequent finding in RET negative tumours. The aims of this study were to analyse survival outcomes in MTC and to evaluate the role of RAS immunohistochemistry in the identification of sporadic disease. MATERIALS AND METHODS: A retrospective cohort study of consecutive patients with MTC was undertaken. The primary outcome measures were overall survival and disease-free survival. Survival analysis was performed on the basis of sporadic and familial disease. Patients had routine RET testing using the capillary (Sanger) sequencing method. Histopathological MTC slides from 100 patients were tested for HRASQ61R, a common somatic RAS mutation in MTC, with mutation-specific immunohistochemistry (IHC). RESULTS: A total of 195 patients had surgical treatment of MTC in the period 1980 to 2016. There were 83 males and 112 females with a mean age of 53.0 years. A total of 39 (20%) patients had familial disease. Sporadic cases had a higher median pre-op calcitonin (969.5 vs. 257.5 pg/ml), greater mean primary tumour size (23.5 vs. 12.5 mm) and more distant metastases (12.8 vs. 10.3%). Multivariate analysis showed age (p = 0.005), Multiple Endocrine Neoplasia Type 2 (MEN2) status (p = 0.021) and distant metastasis (p = 0.002) to be significant independent predictors of survival. Significant independent predictors for disease-free survival were age (p = 0.015), MEN2 (p = 0.002), pre-op calcitonin (p = 0.033) and venous invasion (p = 0.001). The overall 5-year survival was 100% for familial MTC and 78% for sporadic MTC. The 10-year disease-free survival was 94% for familial MTC and 61% for sporadic cases. A total of 100 cases of MTC underwent mutation-specific IHC for HRASQ61R. Of these, 18 had confirmed MEN2. IHC had 100% specificity in excluding MEN2. Twelve (12%) of 100 patients stained positive for HRASQ61R mutation. CONCLUSION: In the era of genetic testing, RET status significantly influences disease-specific survival in MTC. Mutation-specific IHC for HRASQ61R may have a role in the identification of patients presenting with sporadic disease.


Assuntos
Carcinoma Neuroendócrino/genética , Carcinoma Neuroendócrino/mortalidade , Mutação , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/mortalidade , Proteínas ras/genética , Fatores Etários , Calcitonina/análise , Carcinoma Neuroendócrino/cirurgia , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasia Endócrina Múltipla Tipo 2a/patologia , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/cirurgia
3.
Ann Oncol ; 28(7): 1448-1456, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28407030

RESUMO

Intratumoral heterogeneity (ITH) has increasingly being described for multiple cancers as the root cause of therapy resistance. Recent studies have started to explore the scope of ITH in glioblastoma (GBM), a highly aggressive and fatal form of brain tumor, to explain its inevitable therapy resistance and disease relapse. In this review, we detail the emerging data that explores the extensive genetic, cellular and functional ITH present in GBM. We discuss current experimental models of human GBM recurrence and suggest harnessing new technologies (CRISPR-Cas9 screening, CyTOF, cellular barcoding, single cell analysis) to delineate GBM ITH and identify treatment-refractory cell populations, thus opening new therapeutic windows. We will also explore why current therapeutics have failed in clinical trials and how ITH can inform us on developing empiric therapies for the treatment of recurrent GBM.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Resistência a Medicamentos , Glioblastoma/tratamento farmacológico , Recidiva Local de Neoplasia , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Progressão da Doença , Resistência a Medicamentos/efeitos dos fármacos , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/secundário , Humanos , Resultado do Tratamento
4.
J Clin Microbiol ; 55(5): 1454-1468, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28228492

RESUMO

A curated Web-based user-friendly sequence typing tool based on antimicrobial resistance determinants in Neisseria gonorrhoeae was developed and is publicly accessible (https://ngstar.canada.ca). The N. gonorrhoeae Sequence Typing for Antimicrobial Resistance (NG-STAR) molecular typing scheme uses the DNA sequences of 7 genes (penA, mtrR, porB, ponA, gyrA, parC, and 23S rRNA) associated with resistance to ß-lactam antimicrobials, macrolides, or fluoroquinolones. NG-STAR uses the entire penA sequence, combining the historical nomenclature for penA types I to XXXVIII with novel nucleotide sequence designations; the full mtrR sequence and a portion of its promoter region; portions of ponA, porB, gyrA, and parC; and 23S rRNA sequences. NG-STAR grouped 768 isolates into 139 sequence types (STs) (n = 660) consisting of 29 clonal complexes (CCs) having a maximum of a single-locus variation, and 76 NG-STAR STs (n = 109) were identified as unrelated singletons. NG-STAR had a high Simpson's diversity index value of 96.5% (95% confidence interval [CI] = 0.959 to 0.969). The most common STs were NG-STAR ST-90 (n = 100; 13.0%), ST-42 and ST-91 (n = 45; 5.9%), ST-64 (n = 44; 5.72%), and ST-139 (n = 42; 5.5%). Decreased susceptibility to azithromycin was associated with NG-STAR ST-58, ST-61, ST-64, ST-79, ST-91, and ST-139 (n = 156; 92.3%); decreased susceptibility to cephalosporins was associated with NG-STAR ST-90, ST-91, and ST-97 (n = 162; 94.2%); and ciprofloxacin resistance was associated with NG-STAR ST-26, ST-90, ST-91, ST-97, ST-150, and ST-158 (n = 196; 98.0%). All isolates of NG-STAR ST-42, ST-43, ST-63, ST-81, and ST-160 (n = 106) were susceptible to all four antimicrobials. The standardization of nomenclature associated with antimicrobial resistance determinants through an internationally available database will facilitate the monitoring of the global dissemination of antimicrobial-resistant N. gonorrhoeae strains.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Tipagem de Sequências Multilocus/métodos , Neisseria gonorrhoeae/classificação , Neisseria gonorrhoeae/efeitos dos fármacos , Sequência de Aminoácidos , Azitromicina/farmacologia , Cefalosporinas/farmacologia , Fluoroquinolonas/farmacologia , Gonorreia/epidemiologia , Gonorreia/microbiologia , Humanos , Neisseria gonorrhoeae/genética , Neisseria gonorrhoeae/isolamento & purificação
5.
Br J Dermatol ; 176(3): 705-712, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27373931

RESUMO

BACKGROUND: Psoriasis is a common chronic skin condition characterized by excessive inflammation and aberrant epidermal proliferation. Flightless I (Flii) is an actin-remodelling protein that regulates these processes, suggesting a possible role in psoriasis. OBJECTIVES: We sought to determine whether a benefit in psoriasiform dermatitis might occur after modulating Flii gene expression or reducing its levels using neutralizing antibodies. METHODS: Biopsies of psoriatic skin lesions from patients were assessed for Flii levels. Psoriasis-like lesions were induced in Flii heterozygous (Flii+/- ), wild-type (Flii+/+ ) and Flii transgenic (FliiTg/Tg ) mice using topical application of imiquimod. Additionally, psoriasis-induced wild-type mice were treated with topical application of Flii neutralizing antibodies and erythema, inflammation and histology were assessed. RESULTS: Flii was elevated in psoriatic lesions from patients with psoriasis compared with normal human skin. Reducing Flii decreased erythema, inflammatory cell infiltrate, proinflammatory cytokines and the thickness of the epidermis. Topical application of Flii neutralizing antibodies to wild-type mice treated with imiquimod resulted in significantly reduced psoriasiform dermatitis. CONCLUSIONS: Flii is a novel target involved in psoriasiform dermatitis and reducing cutaneous Flii could potentially be a new approach for treating patients with psoriasis.


Assuntos
Anticorpos Neutralizantes/farmacologia , Proteínas do Citoesqueleto/antagonistas & inibidores , Dermatite/tratamento farmacológico , Psoríase/tratamento farmacológico , Administração Cutânea , Aminoquinolinas/administração & dosagem , Aminoquinolinas/toxicidade , Animais , Anticorpos Monoclonais/farmacologia , Proteínas de Transporte , Proteínas do Citoesqueleto/imunologia , Proteínas do Citoesqueleto/metabolismo , Dermatite/fisiopatologia , Modelos Animais de Doenças , Toxidermias/tratamento farmacológico , Toxidermias/etiologia , Feminino , Humanos , Imiquimode , Irritantes/administração & dosagem , Irritantes/toxicidade , Masculino , Camundongos Endogâmicos BALB C , Proteínas dos Microfilamentos , Pessoa de Meia-Idade , Psoríase/induzido quimicamente , Psoríase/fisiopatologia , RNA Mensageiro/metabolismo , Receptor 4 Toll-Like/metabolismo , Transativadores
6.
Scand J Med Sci Sports ; 27(4): 376-384, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27714855

RESUMO

Carbohydrate (CHO) depletion is linked to neuromuscular fatigue during exercise. While its role at peripheral level is relatively well understood, less is known about its impact centrally. The aim of this systematic review was to critically analyze the effects of CHO on central fatigue (CF) assessed by various neurophysiological techniques. Four databases were searched using PRISMA guidelines through February 2016. The inclusion criteria were: CHO as intervention against a placebo control, fatigue induced by prolonged exercise and assessed using neurophysiological measures [voluntary activation (VA), superimposed twitch (SIT), M-wave, electromyography], alongside maximal voluntary contraction (MVC). Seven papers were reviewed, where exercise duration lasted between 115 and 180 min. CHO improved exercise performance in three studies, whereby two of them attributed it to CF via attenuation of VA and SIT reductions, while the other indicated peripheral involvement via attenuation of M-wave reduction. Although a few studies suggest that CHO attenuates CF, data on its direct effects on neurophysiological outcome measures are limited and mixed. Generally, measures employed in these studies were inadequate to conclude central contribution to fatigue. Factors including the techniques used and the lack of controls render additional confounding factors to make definitive deductions. Future studies should employ consistent techniques and appropriate neurophysiological controls to distinguish CHO effect at central level. The use of pharmacological intervention should be incorporated to elucidate involvement of central mechanisms.


Assuntos
Desempenho Atlético , Metabolismo dos Carboidratos , Carboidratos da Dieta/uso terapêutico , Exercício Físico , Fadiga/terapia , Músculo Esquelético/metabolismo , Eletromiografia , Fadiga/metabolismo , Fadiga/prevenção & controle , Humanos , Contração Muscular , Fadiga Muscular
7.
World J Surg ; 40(7): 1618-24, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27138882

RESUMO

BACKGROUND: The BRAF (V600E) mutation is a recognised molecular marker in papillary thyroid cancer (PTC), reported incidence from 30 to 80 %. BRAF(V600E) aberrantly activates the MAPK pathway, a central regulator of cell growth and proliferation. Previous studies have reported conflicting data regarding the impact of BRAF(V600E) on clinicopathological features of PTC. The study aims to determine whether BRAF(V600E) is useful as a prognostic biomarker in PTC. METHODS: A cohort study of patients undergoing surgery for PTC was undertaken. The primary outcome measure was disease-free survival. Secondary outcome measures were tumour size, nodal positivity and radioactive iodine ablation rate. All cases were re-examined to confirm PTC. Immunohistochemistry for BRAF(V600E) was performed on tissue microarrays. A single endocrine pathologist, blinded to clinicopathological data, interpreted staining. RESULTS: 496 patients with PTC were included, and 309 (62 %) were BRAF(V600E) positive. Tumour size was similar for BRAF(V600E)-positive and -negative tumours (21.3 vs. 23.2 mm, p = 0.23). BRAF(V600E)-positive patients were significantly older at first operation (mean age 45 versus 49 years, p = 0.003). BRAF(V600E)-positive PTCs had a higher rate of disease recurrence (12.9 vs. 5.6 %, p = 0.004), lymph node metastasis (44 vs. 29.4 %, p = 0.004) and extra-thyroidal extension (44 vs. 22 %, p < 0.001). Five-year disease-free survival was 89.6 % for BRAF(V600E) positive and 96.3 % for negative tumours, p < 0.001. There was no difference between groups for vascular invasion or multifocality. The mean follow-up was 57 months for both groups. CONCLUSION: BRAF(V600E) in PTC predicts an increased risk of lymph node metastasis, extra-thyroidal extension and reduced disease-free survival. It is an additional useful prognostic biomarker.


Assuntos
Carcinoma/genética , Carcinoma/secundário , Recidiva Local de Neoplasia/genética , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Técnicas de Ablação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Carcinoma/cirurgia , Carcinoma Papilar , Criança , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Humanos , Radioisótopos do Iodo/uso terapêutico , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas Proto-Oncogênicas B-raf/análise , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/cirurgia , Carga Tumoral/genética , Adulto Jovem
8.
Am J Physiol Regul Integr Comp Physiol ; 308(12): R998-1007, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25876651

RESUMO

We investigated the role of exercise intensity and associated central motor drive in determining corticomotoneuronal excitability. Ten participants performed a series of nonfatiguing (3 s) isometric single-leg knee extensions (ISO; 10-100% of maximal voluntary contractions, MVC) and cycling bouts (30-160% peak aerobic capacity, W peak). At various exercise intensities, electrical potentials were evoked in the vastus lateralis (VL) and rectus femoris (RF) via transcranial magnetic stimulation (motor-evoked potentials, MEP), and electrical stimulation of both the cervicomedullary junction (cervicomedullary evoked potentials, CMEP) and the femoral nerve (maximal M-waves, M max). Whereas M max remained unchanged in both muscles (P > 0.40), voluntary electromyographic activity (EMG) increased in an exercise intensity-dependent manner for ISO and cycling exercise in VL and RF (both P < 0.001). During ISO exercise, MEPs and CMEPs progressively increased in VL and RF until a plateau was reached at ∼ 75% MVC; further increases in contraction intensity did not cause additional changes (P > 0.35). During cycling exercise, VL-MEPs and CMEPs progressively increased by ∼ 65% until a plateau was reached at W peak. In contrast, RF MEPs and CMEPs progressively increased by ∼ 110% throughout the tested cycling intensities without the occurrence of a plateau. Furthermore, alterations in EMG below the plateau influenced corticomotoneuronal excitability similarly between exercise modalities. In both exercise modalities, the MEP-to-CMEP ratio did not change with exercise intensity (P > 0.22). In conclusion, increases in exercise intensity and EMG facilitates the corticomotoneuronal pathway similarly in isometric knee extension and locomotor exercise until a plateau occurs at a submaximal exercise intensity. This facilitation appears to be primarily mediated by increases in excitability of the motoneuron pool.


Assuntos
Exercício Físico , Contração Isométrica , Atividade Motora , Córtex Motor/fisiologia , Neurônios Motores/fisiologia , Tratos Piramidais/fisiologia , Músculo Quadríceps/inervação , Adulto , Ciclismo , Estimulação Elétrica/métodos , Eletromiografia , Potencial Evocado Motor , Nervo Femoral/fisiologia , Humanos , Joelho , Masculino , Fatores de Tempo , Estimulação Magnética Transcraniana
9.
Colorectal Dis ; 17(4): 298-303, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25605376

RESUMO

AIM: Incomplete colonoscopy indicated for the detection of neoplasia occurs in 2-23% of patients, but there is little information on the long-term outcome of such patients. METHOD: All patients who underwent colonoscopy over 5 years at the Royal Liverpool University Hospital with a follow-up of up to 5 years were identified. RESULTS: The risk of colorectal cancer (CRC) was 2.9% (312/10 580) for all patients undergoing colonoscopy. For a failed colonoscopy, the risk was five-fold higher [14.3% (99/693)]. The mean age of the patients was 61 years and 58% were female. Following incomplete colonoscopy the risk of finding additional CRC, advanced colonic neoplasia and extracolonic neoplasia on subsequent investigation was 6.2%, 3.2% and 1.9%. The diagnostic yield on subsequent investigation for CRC or colonic polyps was 7% for repeat colonoscopy, 13.4% for computed tomography colonography, 10.3% for standard computed tomography and 1.8% for barium enema. In the 363 patients who were not offered a subsequent investigation, there was no further instance of CRC or CRC-related mortality over a 36-month period. CONCLUSION: Although the risk of CRC is higher in patients who have had a failed colonoscopy, a protocol approach of subsequent investigation should not replace clinical assessment on whether another test is necessary in the light of the good outcome of patients who were not subsequently investigated.


Assuntos
Adenoma/diagnóstico , Carcinoma/diagnóstico , Pólipos do Colo/diagnóstico , Colonoscopia , Neoplasias Colorretais/diagnóstico , Adenoma/epidemiologia , Idoso , Sulfato de Bário , Carcinoma/epidemiologia , Estudos de Coortes , Doenças do Colo/diagnóstico , Doenças do Colo/epidemiologia , Pólipos do Colo/epidemiologia , Colonografia Tomográfica Computadorizada , Neoplasias Colorretais/epidemiologia , Constrição Patológica/diagnóstico , Constrição Patológica/epidemiologia , Meios de Contraste , Diverticulose Cólica/diagnóstico , Diverticulose Cólica/epidemiologia , Enema , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
10.
Int Endod J ; 48(6): 549-55, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25070206

RESUMO

AIM: To evaluate the anatomical relationship between the roots of mandibular second molars and the inferior alveolar nerve (IAN) in relation to the risk of potential nerve injury during root canal treatment. METHODOLOGY: Cone-beam computed tomography (CBCT) images from the patient record database at a dental hospital were selected. The anonymized CBCT images were reconstructed and examined in three planes (coronal, axial and sagittal) using 3D viewing software. The relationship between each root apex of mandibular second molars and the IAN was evaluated by measuring the horizontal and vertical distances from coronal CBCT sections, and the actual distance was then calculated mathematically using Pythagoras' theorem. RESULTS: In 55% of the 272 mandibular second molar roots evaluated, from a total of 134 scans, the distance between the anatomical root apex and the IAN was ≤3 mm. CONCLUSIONS: In over 50% of the cases evaluated, there was an intimate relationship between the roots of mandibular second molars and the inferior alveolar nerve (IAN). Therefore, root canal treatment of mandibular second molars may pose a more significant potential risk of IAN injury; necessary precautions should be exercised, and the prudent use of CBCT should be considered if an intimate relationship is suspected.


Assuntos
Mandíbula/anatomia & histologia , Nervo Mandibular/anatomia & histologia , Dente Molar/anatomia & histologia , Raiz Dentária/anatomia & histologia , Tomografia Computadorizada de Feixe Cônico , Humanos , Mandíbula/diagnóstico por imagem , Nervo Mandibular/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador , Raiz Dentária/diagnóstico por imagem
11.
Br J Surg ; 101(10): 1252-6, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25043401

RESUMO

BACKGROUND: The accepted management of lithium-associated hyperparathyroidism (LiHPT) is open four-gland parathyroid exploration (OPTX). This approach has recently been the subject of controversy. A recent study has shown very high long-term recurrence rates after OPTX, whereas some have promoted unilateral focused parathyroidectomy as appropriate management. The aim was to evaluate long-term outcomes after surgery for LiHPT and to assess the accuracy of preoperative imaging. METHODS: This was a retrospective cohort study that comprised all patients undergoing initial surgery for LiHPT between 1990 and 2013. The cumulative recurrence rate was calculated by the Kaplan-Meier method. The sensitivity and specificity of sestamibi scintigraphy and ultrasound imaging for identification of single-gland versus multigland disease was investigated using intraoperative assessment as reference. RESULTS: Of 48 patients, 45 had OPTX and three underwent focused parathyroidectomy. Multiglandular disease was documented in 27 patients and 21 had a single adenoma. The median follow-up was 5·9 (range 0·3-22) years and 16 patients died during follow-up. The 10-year cumulative recurrence rate was 16 (95 per cent confidence interval 2 to 29) per cent. No permanent complications occurred after primary surgery for LiHPT. Twenty-four patients had at least one preoperative ultrasound or sestamibi scan. For concordant sestamibi scintigraphy and ultrasound imaging, the sensitivity and specificity for identifying single-gland versus multigland disease was five of nine and five of eight respectively. CONCLUSION: Surgery provided a safe and effective management option for patients with LiHPT in this series, with a long-term cure rate of well over 80 per cent.


Assuntos
Antidepressivos/efeitos adversos , Hiperparatireoidismo/cirurgia , Carbonato de Lítio/efeitos adversos , Paratireoidectomia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico por Imagem/métodos , Feminino , Humanos , Hiperparatireoidismo/induzido quimicamente , Hiperparatireoidismo/diagnóstico , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios/métodos , Recidiva , Estudos Retrospectivos , Resultado do Tratamento
12.
Environ Sci Technol ; 48(12): 6891-8, 2014 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-24823240

RESUMO

A Serratia sp. bacterium manufactures amorphous calcium phosphate nanominerals (BHAP); this material has shown increased sorption capacity for divalent radionuclide capture. When heat-treated (≥450 °C) the cell biomass is removed and the biominerals are transformed to hydroxyapatite (HAP). Using a multimethod approach, we have elucidated both the site preferences and stability of analogue radionuclide incorporation for Sr, Co, Eu, and U. Strontium incorporates within the bulk amorphous inorganic phase of BHAP; however, once temperature modified to crystalline HAP, bonding was consistent with Sr substitution at the Ca(1) and/or Ca(2) sites. Cobalt incorporation occurs within the bulk inorganic amorphous phase of BHAP and within the amorphous grain boundaries of HAP. Europium (an analogue for trivalent actinides) substituted at the Ca(2) and/or the Ca(3) position of tricalcium phosphate, a known component of HAP grain boundaries. Uranium was surface complexed with no secondary minerals detected. With multiple sites for targeted radionuclide incorporation, high loadings, and good stability against remobilization, BHAP is shown to be a potential material for the remediation of aqueous radionuclide in groundwater.


Assuntos
Bactérias/metabolismo , Fosfatos de Cálcio/metabolismo , Minerais/metabolismo , Nanopartículas/química , Radioisótopos/isolamento & purificação , Adsorção , Biodegradação Ambiental , Durapatita/química , Água Subterrânea/química , Íons , Nanopartículas/ultraestrutura , Tamanho da Partícula , Poluentes Radioativos da Água/isolamento & purificação , Espectroscopia por Absorção de Raios X , Difração de Raios X
14.
Digit Health ; 10: 20552076241253093, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38726214

RESUMO

Objectives: Increased rates of mental health disorders and substance use among youth and young adults have increased globally, furthering the strain on an already burdened mental health system. Digital solutions have been proposed as a potential option for the provision of timely mental health services for youth, with little research exploring mental health professional views about using such innovative tools. In Alberta, Canada, we are evaluating the implementation and integration of a digital mental health (dMH) platform into existing service pathways. Within this paper we seek to explore mental health professionals' perceptions of the barriers and facilitators that may influence their utilization of digital MH-enabled measurement-based care (MBC) with the youth who access their services. Methods: A qualitative, descriptive methodology was used to inductively generate themes from focus groups conducted with mental health professionals from specialized mental health services and primary care networks in Alberta. Results: As mental health professionals considered the barriers and facilitators of using dMH with youth, they referenced individual and family barriers and facilitators to consider. Providers highlighted perceived barriers, including: first, cultural stigma, family apprehension about mental health care, and parental access to dMH and MBC as deterrents to providers adopting digital platforms in routine care; second, perceptions of increased responsibility and liability for youth in crisis; third, perception that some psychiatric and neurodevelopmental disorders in youth are not amenable to dMH; fourth, professionals contemplated youth readiness to engage with dMH-enabled MBC. Participants also highlighted pertinent facilitators to dMH use, noting: first, the suitability of dMH for youth with mild mental health concerns; second, youth motivated to report their changes in mental health symptoms; and lastly, youth proficiency and preference for dMH options. Conclusions: By identifying professionals' perceptions of barriers and facilitators for youth users, we may better understand how to address misconceptions about who is eligible and appropriate for dMH through training and education.

15.
Methods ; 57(4): 486-98, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22750306

RESUMO

The last 100 years of enquiry into the fundamental basis of humoral immunity has resulted in the identification of antibodies as key molecular sentinels responsible for the in vivo surveillance, neutralization and clearance of foreign substances. Intense efforts aimed at understanding and exploiting their exquisite molecular specificity have positioned antibodies as a cornerstone supporting basic research, diagnostics and therapeutic applications [1]. More recently, efforts have aimed to circumvent the limitations of developing antibodies in animals by developing wholly in vitro techniques for designing antibodies of tailored specificity. This has been realized with the advent of synthetic antibody libraries that possess diversity outside the scope of natural immune repertoires and are thus capable of yielding specificities not otherwise attainable. This review examines the convergence of technologies that have contributed to the development of combinatorial phage-displayed antibody libraries. It further explores the practical concepts that underlie phage display, antibody diversity and the methods used in the generation of and selection from phage-displayed synthetic antibody libraries, highlighting specific applications in which design approaches gave rise to specificities that could not easily be obtained with libraries based upon natural immune repertories.


Assuntos
Anticorpos/genética , Técnicas de Visualização da Superfície Celular , Animais , Anticorpos/química , Anticorpos/imunologia , Anticorpos Imobilizados , Diversidade de Anticorpos , Especificidade de Anticorpos , Bacteriófagos/genética , Regiões Determinantes de Complementaridade , Evolução Molecular Direcionada , Vetores Genéticos , Humanos , Biblioteca de Peptídeos
16.
Trials ; 24(1): 515, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37568158

RESUMO

BACKGROUND: Severe alcoholic hepatitis (SAH) is associated with high mortality. Numerous studies and meta-analysis have reported that corticosteroids reduce the 28-day mortality in SAH, but not the 6-month mortality. Therefore, newer treatments for SAH need to be studied. A pilot study from our group had recently treated ten patients with SAH with bovine colostrum (BC) [20 g thrice in a day for 8 weeks] and prednisolone. This therapy improved the biological functions and 3-month mortality. However, as more and more data showed the failure of corticosteroids to improve the 3- and 6-month mortality, especially in patients with high mDF and MELD scores, we planned this trial to study the safety and efficacy of BC (without corticosteroids) in the treatment of SAH. METHOD: This is a multicenter, parallel, double-blind, randomized (1:1) placebo-controlled trial, which will enroll 174 patients with SAH from 5 academic centers in the India. Patients will receive freeze-dried BC or placebo by random 1:1 allocation for 4 weeks. The primary outcome measure is survival at 3 months. The secondary outcome measures are survival at 1 month, change in mDF and MELD scores, change in endotoxin and cytokines (alpha TNF, IL6, and IL8) levels, number of episodes of sepsis [pneumonia, spontaneous bacterial peritonitis (SBP), cellulitis, urinary tract infection (UTI)] from baseline to 4 weeks. DISCUSSION: This study will evaluate the safety and efficacy of bovine colostrum in improving the survival of patients with SAH. TRIAL REGISTRATION: ClinicalTrials.gov NCT02473341. Prospectively registered on June 16, 2015.


Assuntos
Hepatite Alcoólica , Feminino , Gravidez , Humanos , Animais , Bovinos , Resultado do Tratamento , Hepatite Alcoólica/diagnóstico , Hepatite Alcoólica/tratamento farmacológico , Projetos Piloto , Colostro , Corticosteroides , Método Duplo-Cego , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
17.
Br J Cancer ; 107(3): 501-7, 2012 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-22782341

RESUMO

BACKGROUND: Our earlier reports demonstrated that membrane-bound semaphorin 5A (SEMA5A) is expressed in aggressive pancreatic cancer cells and tumours, and promotes tumour growth and metastasis. In this study, we examine whether (1) pancreatic cancer cells secrete SEMA5A and (2) that secreted SEMA5A modulates certain phenotypes associated with tumour progression, angiogenesis and metastasis through various other molecular factors and signalling proteins. METHODS AND RESULTS: In this study, we show that human pancreatic cancer cell lines secrete the extracellular domain (ECD) of SEMA5A (SEMA5A-ECD) and overexpression of mouse Sema5A-ECD in Panc1 cells (not expressing SEMA5A; Panc1-Sema5A-ECD; control cells - Panc1-control) significantly increases their invasion in vitro via enhanced ERK phosphorylation. Interestingly, orthotopic injection of Panc1-Sema5A-ECD cells into athymic nude mice results in a lower primary tumour burden, but enhances the micrometastases to the liver as compared with Panc1-control cells. Furthermore, there is a significant increase in proliferation of endothelial cells treated with conditioned media (CM) from Panc1-Sema5A-ECD cells and a significant increase in microvessel density in Panc1-Sema5A-ECD orthotopic tumours compared with those from Panc1-control cells, suggesting that the increase in liver micrometastases is probably due to increased tumour angiogenesis. In addition, our data demonstrate that this increase in endothelial cell proliferation by Sema5A-ECD is mediated through the angiogenic molecules - interleukin-8 and vascular endothelial growth factor. CONCLUSION: Taken together, these results suggest that a bioactive, secreted form of Sema5A-ECD has an intriguing and potentially important role in its ability to enhance pancreatic tumour invasiveness, angiogenesis and micrometastases.


Assuntos
Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Indutores da Angiogênese/metabolismo , Animais , Processos de Crescimento Celular/fisiologia , Progressão da Doença , Células Endoteliais/metabolismo , Células Endoteliais/patologia , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Interleucina-8/genética , Interleucina-8/metabolismo , Neoplasias Hepáticas/secundário , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Micrometástase de Neoplasia , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Proteínas do Tecido Nervoso/genética , Neoplasias Pancreáticas/genética , Fosforilação/genética , Semaforinas , Células Tumorais Cultivadas , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
18.
Clin Exp Allergy ; 42(1): 144-55, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22093101

RESUMO

BACKGROUND: The pathophysiology of asthma involves allergic inflammation and remodelling in the airway and airway hyperresponsiveness (AHR) to cholinergic stimuli, but many details of the specific underlying cellular and molecular mechanisms remain unknown. Periostin is a matricellular protein with roles in tissue repair following injury in both the skin and heart. It has recently been shown to be up-regulated in the airway epithelium of asthmatics and to increase active TGF-ß. Though one might expect periostin to play a deleterious role in asthma pathogenesis, to date its biological role in the airway is unknown. OBJECTIVE: To determine the effect of periostin deficiency on airway responses to inhaled allergen. METHODS: In vivo measures of airway responsiveness, inflammation, and remodelling were made in periostin deficient mice and wild-type controls following repeated intranasal challenge with Aspergillus fumigatus antigen. In vitro studies of the effects of epithelial cell-derived periostin on murine T cells were also performed. RESULTS: Surprisingly, compared with wild-type controls, periostin deficient mice developed increased AHR and serum IgE levels following allergen challenge without differences in two outcomes of airway remodelling (mucus metaplasia and peribronchial fibrosis). These changes were associated with decreased expression of TGF-ß1 and Foxp3 in the lungs of periostin deficient mice. Airway epithelial cell-derived periostin-induced conversion of CD4(+) CD25(-) cells into CD25(+) , Foxp3(+) T cells in vitro in a TGF-ß dependent manner. CONCLUSIONS AND CLINICAL RELEVANCE: Allergen-induced increases in serum IgE and bronchial hyperresponsiveness are exaggerated in periostin deficient mice challenged with inhaled aeroallergen. The mechanism of periostin's effect as a brake on allergen-induced responses may involve augmentation of TGF-ß-induced T regulatory cell differentiation.


Assuntos
Hiper-Reatividade Brônquica/imunologia , Moléculas de Adesão Celular/metabolismo , Hipersensibilidade/imunologia , Imunoglobulina E/sangue , Fator de Crescimento Transformador beta/metabolismo , Remodelação das Vias Aéreas , Animais , Antígenos de Fungos/imunologia , Aspergillus fumigatus/imunologia , Asma/imunologia , Asma/fisiopatologia , Moléculas de Adesão Celular/deficiência , Moléculas de Adesão Celular/genética , Modelos Animais de Doenças , Hipersensibilidade/fisiopatologia , Imunoglobulina E/imunologia , Inflamação , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fator de Crescimento Transformador beta/imunologia
19.
Br J Surg ; 99(5): 688-92, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22287186

RESUMO

BACKGROUND: Total thyroidectomy, rather than bilateral subtotal thyroidectomy, is now accepted as the preferred management for bilateral benign multinodular goitre (BMNG) in order to reduce the need for reoperative surgery. The aim of this study was to examine whether this approach has had an impact on presentation for bilateral reoperative thyroid surgery. METHODS: This was a retrospective cohort study. The study group comprised patients presenting with recurrent BMNG who underwent bilateral reoperative thyroid surgery following previous bilateral subtotal or partial thyroidectomy. They were compared with patients undergoing unilateral reoperative thyroid surgery following previous lobectomy, and those undergoing primary total thyroidectomy for BMNG. RESULTS: Between 1 January 1987 and 31 December 2009, 12 354 consecutive thyroid procedures were undertaken. Among those with BMNG, primary total thyroidectomy was undertaken in 3298 patients, unilateral reoperative thyroidectomy in 337 and bilateral reoperative thyroidectomy in 191. Presentations of patients with recurrent BMNG declined gradually over the study period following the change in policy from subtotal to total thyroidectomy; only five patients (representing less than 0.5 per cent of all thyroid surgery) underwent bilateral reoperative surgery for BMNG in the last year of the study. Four of these patients had their initial operation before 1987 and in another unit, whereas the remaining patient initially had surgery overseas. CONCLUSION: The introduction of a policy of initial total thyroidectomy for bilateral BMNG has essentially eliminated the need for bilateral reoperative surgery for recurrent goitre.


Assuntos
Bócio Nodular/cirurgia , Tireoidectomia/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/cirurgia , Recidiva , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Adulto Jovem
20.
Clin Exp Dermatol ; 37(1): 6-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21981313

RESUMO

BACKGROUND: The ratio of benign moles excised for each malignant melanoma (MM) diagnosed, i.e. the number needed to treat (NNT), may be a useful indicator of diagnostic accuracy and the efficient use of healthcare resources, and may have personal implications for the patient. AIM: To assess the NNT for a group of consultant dermatologists serving a population of 600,000, and to compare this with similar studies from other countries. METHODS: This was a retrospective analysis of data on pigmented lesions excised over a 5-year period (2005-2009). The lesions were divided into three groups: benign naevi (BN), dysplastic naevi (DN) and MM. The NNT ratio was calculated as (BN + DN + MM)/MM. RESULTS: In total, 4691 lesions were examined. The overall mean NNT was 6.3, with a range of 4.9-11.3 for each of nine consultant dermatologists. The mean NNT was 7.6 for female and 4.8 for male patients. There were more patients with BN (n = 3534; 75%) than with DN (n = 407; 9%) or MM (n = 750; 16%). The gender representation was similar in the DN and MM groups, but had a disproportionately female bias in the BN group (67% female, 33% male patients). Overall, there were more female patients in all three groups [2962 female patients (63%) and 1729 male patients (37%)]. CONCLUSIONS: The NNT of 6.3 in this study compares favourably with NNT ratios from studies of dermatologists from other countries. This study may encourage other countries and individual doctors to assess their NNT ratios, as it may be an important indicator of the efficient use of resources and the avoidance of unnecessary surgery for patients.


Assuntos
Melanoma/cirurgia , Nevo Pigmentado/cirurgia , Neoplasias Cutâneas/cirurgia , Adulto , Análise de Variância , Dermatologia/normas , Dermatologia/estatística & dados numéricos , Feminino , Humanos , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Nevo Pigmentado/patologia , Estudos Retrospectivos , Distribuição por Sexo , Neoplasias Cutâneas/patologia , País de Gales
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