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1.
Ann Oncol ; 30(4): 629-636, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30657857

RESUMO

BACKGROUND: In the era of precision medicine and HPV-related oropharyngeal squamous cell carcinoma (OPSCC), it is relevant to assess the risk of not only survival, but also the risk of local, regional, or distant treatment failure. The UICC 8th edition uses the surrogate marker p16 to stratify for HPV association but discordance between p16 status and HPV association has been shown. The purpose of this study was to develop a prognostic model to predict the risk of local, regional, and distant metastases and non-cancer-related death for patients with OPSCC, test the prognostic relevance of adding HPV DNA and p16 status, and validate the findings in an independent external dataset. PATIENTS AND METHODS: Consecutive patients diagnosed with OPSCC and treated with curative radiotherapy with or without cisplatin in eastern Denmark from 2000 to 2014 were included. Characteristics included age, gender, TNM stage, smoking habits, performance status, and HPV status assessed with p16 and HPV DNA. The information was used to develop a prognostic model for first site of failure with four competing events: recurrence in T-, N-, and M-site, and death with no evidence of disease. RESULTS: Overall 1243 patients were eligible for the analysis. A prognostic model with the four events was developed and externally validated in an independent dataset with a heterogeneously treated patient population from another institution. The individual prognostication from the competing risk analysis is displayed in a user friendly online tool (https://rasmussen.shinyapps.io/OPSCCmodelHPV_p16/). Replacing p16 status with the combined variable HPV/p16 status influenced the HR and patients with HPV-/p16+ had significantly higher HR of M-site recurrence than HPV+/p16+ with a HR = 2.56; CI [1.30; 5.02]; P = 0.006 (P = 0.013 in the validation cohort). CONCLUSION: Patients with HPV-/p16+ have significantly higher risk of M-site recurrence and could potentially be relevant candidates for clinical trials testing systemic treatments in combination with conventional treatments.


Assuntos
Biomarcadores Tumorais/análise , Modelos Biológicos , Recidiva Local de Neoplasia/epidemiologia , Neoplasias Orofaríngeas/terapia , Infecções por Papillomavirus/terapia , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Idoso , Biomarcadores Tumorais/genética , Quimiorradioterapia/métodos , Cisplatino/uso terapêutico , Tomada de Decisão Clínica , Inibidor p16 de Quinase Dependente de Ciclina/análise , DNA Viral/isolamento & purificação , Conjuntos de Dados como Assunto , Dinamarca/epidemiologia , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/prevenção & controle , Neoplasias Orofaríngeas/genética , Neoplasias Orofaríngeas/mortalidade , Neoplasias Orofaríngeas/patologia , Papillomaviridae/genética , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/mortalidade , Infecções por Papillomavirus/patologia , Valor Preditivo dos Testes , Prognóstico , Medição de Risco/métodos , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia
2.
Respir Res ; 20(1): 258, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31730462

RESUMO

INTRODUCTION: Prognostic biomarkers in asthma are needed. The biomarker soluble urokinase plasminogen activator receptor (suPAR) has been associated with asthma control and with prognosis in acutely admitted medical patients. We investigated if suPAR and blood eosinophil counts at the time of admission for asthma are associated with readmission and mortality. METHODS: Our cohort comprised 1341 patients (median age 45.3, IQR 30.1-63.1) acutely admitted with a diagnosis of asthma to Hvidovre Hospital, Denmark (November 2013 to March 2017). Patients had suPAR and blood eosinophils measured at admission. Outcomes were 365-day readmission and all-cause mortality. Logistic regression analysis adjusted for age, sex, C-reactive protein, and Charlson comorbidity score was used to assess the association of the two biomarkers with readmission and all-cause mortality. RESULTS: Compared to event-free patients, patients who were either readmitted (n = 452, 42.3%) or died (n = 57, 5.3%) had significantly higher suPAR concentrations (p < 0.0001) and lower eosinophil counts (p = 0.0031) at admission. The highest odds of readmission or mortality were observed for patients in either the 4th suPAR quartile (p < 0.0001) or with eosinophil counts < 150 cells/µL at admission. Increasing levels of suPAR were associated with 365-day readmission (OR 1.3 [1.0-1.6]; p = 0.05) and mortality (OR 2.9 [1.7-5.1]; p = 0.0002). Eosinophil count > 300 cells/µL was significantly associated with lower odds of readmission (OR 0.64 [0.5-0.9]; p = 0.005) and lower mortality (OR 0.7 [0.6-0.9]; p = 0.0007). CONCLUSIONS: In patients acutely admitted with asthma, elevated suPAR concentrations together with blood eosinophil count < 150 cells/µL at the time of hospital admission were associated with both 365-day all-cause readmission and mortality.


Assuntos
Asma/sangue , Asma/mortalidade , Eosinófilos/metabolismo , Readmissão do Paciente/tendências , Receptores de Ativador de Plasminogênio Tipo Uroquinase/sangue , Adulto , Asma/diagnóstico , Biomarcadores/sangue , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade/tendências , Sistema de Registros , Estudos Retrospectivos
3.
Eur Arch Otorhinolaryngol ; 276(10): 2895-2902, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31297609

RESUMO

PURPOSE: The purpose of this study was to assess the use of 18F-FDG PET/CT scans for detecting distant metastases in patients with recurrent head and neck squamous cell carcinoma (HNSCC) and investigate the treatment and survival of patients with recurrence. METHODS: In this retrospective study, consecutive head and neck cancer patients referred for FDG PET/CT scan between 2012 and 2014 were included. Patient records were reviewed and only patients with recurrence of HNSCC were enrolled for further analysis. Information on distant metastases, surgery and survival was collected. A Kaplan-Meier analysis was used to report survival. RESULTS: Overall 275 PET/CT scans were performed due to suspected recurrence, and in 166 scans (144 patients), recurrence of HNSCC was confirmed, making them eligible for further analysis. Distant metastases were revealed in 29.8% of the scans (n = 51) and the proportion of revealed metastases remained constant at approximately 30% each year. Although the number of performed scans increased twofold each year, there was no statistically significant change in the proportion of scans with distant metastasis (p = 0.55). The distant metastases were most often seen in the lungs (n = 44) and bone (n = 15). A few patients had widespread dissemination to other areas. Salvage surgery was performed following 81 of the 166 PET/CT scans. Seven of the patients who underwent salvage surgery had M-site oligo-metastases. Patients who underwent salvage surgery had a median survival of 22 months whereas patients not treated with salvage surgery had a median survival of 6 months. After 5 years, 21% of the patients selected for salvage surgery were alive. CONCLUSIONS: Distant metastases occur frequently in patients with recurrent HNSCC disease and the proportion of revealed distant metastases remained the same (30%). Imaging with FDG PET/CT can be recommended in patients with recurrent HNSCC prior to putative salvage surgery.


Assuntos
Neoplasias Ósseas , Neoplasias de Cabeça e Pescoço , Neoplasias Pulmonares , Recidiva Local de Neoplasia/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Protocolos Antineoplásicos , Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/secundário , Neoplasias Ósseas/cirurgia , Dinamarca/epidemiologia , Feminino , Fluordesoxiglucose F18/farmacologia , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos/farmacologia , Estudos Retrospectivos , Terapia de Salvação/métodos , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Análise de Sobrevida
6.
Rhinology ; 56(1): 59-64, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29166423

RESUMO

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a common inflammatory disorder associated with lower airway disease. However, only few studies of CRSwNP from outside secondary/tertiary care centres have been published. We recently reported an asthma frequency of 44% and 65% in primary and secondary care patients respectively. Therefore, we hypothesise that inflammation of the lower airways could be present in all CRSwNP patients, even without asthma. Here, we assessed the degree of lower and upper airway inflammation using exhaled and nasal nitric oxide (NO) in primary care CRSwNP patients with and without asthma. METHODS: Fifty-seven patients who met the EPOS criteria for CRSwNP were prospectively recruited from primary care ear, nose and throat clinics. Nasal endoscopy was performed by an ear, nose and throat specialist upon enrolment. Additionally, 30 healthy controls were enrolled. Expiratory and nasal NO measurements and thorough pulmonary evaluation were performed. Pulmonary disease was diagnosed by a respiratory physician. RESULTS: Fifty-nine percent of CRSwNP patients with asthma showed elevated expiratory NO; the same was seen in 29% of non-asthmatic CRSwNP patients. Compared with controls, a high level of exhaled NO was significantly more prevalent in CRSwNP irrespective of asthma-status. Nasal NO was significantly lower in patients with CRSwNP compared with controls. CONCLUSION: Subclinical eosinophilic lower airway inflammation is common in CRSwNP in the primary sector, even in the absence of asthma.


Assuntos
Pólipos Nasais/complicações , Óxido Nítrico/análise , Rinite/complicações , Sinusite/complicações , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Doença Crônica , Endoscopia , Expiração , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atenção Primária à Saúde , Estudos Prospectivos , Testes de Função Respiratória
7.
Rhinology ; 55(3): 195-201, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28492609

RESUMO

BACKGROUND: Systemic glucocorticoids are often used in the treatment of chronic rhinosinusitis with nasal polyps (CRSwNP), and osteoporosis is a well-known complication to steroid treatment, associated with significant morbidity. Nevertheless, the burden of steroid induced osteoporosis is unknown in patients with CRSwNP. We aimed to assess the risk of acquiring osteoporosis caused by oral steroids in patients with CRSwNP, and provide recommendations on future research and guidelines. METHODOLOGY: Cochrane Review Database, EMBASE, Ovid Medline, and PubMed were searched for studies including adult patients with CRSwNP treated with oral steroids. Outcomes were Bone Mineral Density (BMD) and prevalence of fractures in relation to dose and duration of oral steroids. In addition, we reviewed general guidelines for treatment with oral steroids. RESULTS: We identified two studies (n=243) that met the inclusion criteria. Doses and durations of oral steroids were over 5 mg/day for more than 3 months and 1 mg/kg body weight/day for 6 to 10 days for 4 or more courses/year. The prevalence of low bone mass was 39% and 61%, respectively. It was not possible to quantify the overall risk of osteoporosis induced by oral steroids from the studies. No studies evaluated prevalence of fracture. CONCLUSIONS: Registry studies and randomized controlled trials would be needed to assess the risk of osteoporosis in CRSwNP patients and future guidelines should include recommendations regarding preventive treatment and recommendations on doses and durations of oral steroids.


Assuntos
Glucocorticoides/química , Glucocorticoides/uso terapêutico , Pólipos Nasais/complicações , Osteoporose/complicações , Esteroides/farmacologia , Administração Oral , Doença Crônica , Humanos , Pólipos Nasais/fisiopatologia , Esteroides/química
8.
Carbohydr Polym ; 291: 119560, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35698386

RESUMO

An environmentally benign synthesis of a magnetically responsive carboxymethylated cellulose nanofibril-based material is reported. Applied experimental conditions lead to the in-situ formation of magnetite nanoparticles with primary particle sizes of 2.0-4.0 nm or secondary particles of 3.6-16.4 nm depending on whether nucleation occurred between individual carboxymethylated cellulose nanofibrils, or on exposed fibril surfaces. The increase in magnetite particle size on the cellulose fibril surfaces was attributed to Ostwald ripening, while the small particles formed within the carboxymethyl cellulose aggregates were presumably due to steric interactions. The magnetite nanoparticles were capable of coordinating to carboxymethylated cellulose nanofibrils to form large "fibre-like" assemblies. The confinement of small particles within aggregates of reductive cellulose molecules was most likely responsible for excellent conservation of magnetic characteristics on storage of this material. The possibility for using the material in drug delivery applications with release rate controlled by daylight illumination is presented.


Assuntos
Carboximetilcelulose Sódica , Celulose , Sistemas de Liberação de Medicamentos , Óxido Ferroso-Férrico , Tamanho da Partícula
9.
J Prev Alzheimers Dis ; 9(1): 30-39, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35098971

RESUMO

BACKGROUND: Interventions simultaneously targeting multiple risk factors and mechanisms are most likely to be effective in preventing cognitive impairment. This was indicated in the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER) testing a multidomain lifestyle intervention among at-risk individuals. The importance of medical food at the early symptomatic disease stage, prodromal Alzheimer's disease (AD), was emphasized in the LipiDiDiet trial. The feasibility and effects of multimodal interventions in prodromal AD are unclear. OBJECTIVES: To evaluate the feasibility of an adapted FINGER-based multimodal lifestyle intervention, with or without medical food, among individuals with prodromal AD. METHODS: MIND-ADmini is a multinational proof-of-concept 6-month randomized controlled trial (RCT), with four trial sites (Sweden, Finland, Germany, France). The trial targeted individuals with prodromal AD defined using the International Working Group-1 criteria, and with vascular or lifestyle-related risk factors. The parallel-group RCT includes three arms: 1) multimodal lifestyle intervention (nutritional guidance, exercise, cognitive training, vascular/metabolic risk management and social stimulation); 2) multimodal lifestyle intervention+medical food (Fortasyn Connect); and 3) regular health advice/care (control group). Primary outcomes are feasibility and adherence. Secondary outcomes are adherence to the individual intervention domains and healthy lifestyle changes. RESULTS: Screening began on 28 September 2017 and was completed on 21 May 2019. Altogether 93 participants were randomized and enrolled. The intervention proceeded as planned. CONCLUSIONS: For the first time, this pilot trial tests the feasibility and adherence to a multimodal lifestyle intervention, alone or combined with medical food, among individuals with prodromal AD. It can serve as a model for combination therapy trials (non-pharma, nutrition-based and/or pharmacological interventions).


Assuntos
Doença de Alzheimer , Transtornos Cognitivos , Disfunção Cognitiva , Idoso , Doença de Alzheimer/prevenção & controle , Transtornos Cognitivos/prevenção & controle , Disfunção Cognitiva/prevenção & controle , Humanos , Estilo de Vida , Projetos Piloto
10.
Neuron ; 28(2): 385-97, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11144350

RESUMO

We have purified and characterized a factor, from the conditioned medium of neural stem cell cultures, which is required for fibroblast growth factor 2's (FGF-2) mitogenic activity on neural stem cells. This autocrine/paracrine cofactor is a glycosylated form of cystatin C (CCg), whose N-glycosylation is required for its activity. We further demonstrated that, both in vitro and in vivo, neural stem cells undergoing cell division are immunopositive for cystatin C. Finally, we showed in vivo functional activity of CCg by demonstrating that the combined delivery of FGF-2 and CCg to the adult dentate gyrus stimulated neurogenesis. We propose that the process of neurogenesis is controlled by the cooperation between trophic factors and autocrine/paracrine cofactors, of which CCg is a prototype.


Assuntos
Cistatinas/química , Cistatinas/metabolismo , Fator 2 de Crescimento de Fibroblastos/metabolismo , Neurônios/metabolismo , Células-Tronco/metabolismo , Animais , Comunicação Autócrina/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Meios de Cultivo Condicionados/química , Cistatina C , Cistatinas/genética , Cistatinas/farmacologia , Giro Denteado/citologia , Giro Denteado/efeitos dos fármacos , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/farmacologia , Glicosilação , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Dados de Sequência Molecular , Peso Molecular , Neurônios/citologia , Neurônios/efeitos dos fármacos , Comunicação Parácrina/efeitos dos fármacos , Processamento de Proteína Pós-Traducional , Ratos , Análise de Sequência de Proteína , Transplante de Células-Tronco , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos
11.
Hepatogastroenterology ; 54(79): 2024-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18251152

RESUMO

BACKGROUND/AIMS: Budesonide controlled-release (CR) capsules are effective for inducing remission of Crohn's disease (CD) and are associated with fewer side effects than conventional corticosteroids. A compassionate-use program was implemented in countries where this treatment was unavailable. This paper reports the findings of this program. METHODOLOGY: Physicians were allowed to apply to AstraZeneca for a supply of budesonide CR capsules primarily for patients with CD who had experienced unacceptable side effects from conventional steroids or were unresponsive to other drugs. Physicians were requested to record adverse events (AEs) and patient response (1 = 'moderate'; 2 = 'well'; 3 = 'very well'). RESULTS: Four thousand and ninety-two patients were enrolled. There were 232 AE reports involving 326 different symptoms. There were 138 serious AEs (mainly gastrointestinal), and four deaths. Ten serious AEs were considered related to budesonide (no deaths). Budesonide was discontinued as a result of AEs in 147 patients (75 due to serious AEs, mainly gastrointestinal). Efficacy data were obtained from 1188 patients, with 943 (79%) responding 'well' or 'very well'. In the subgroups of patients that were young, elderly, or had unsuccessfully received immunosuppressants previously, the mean patient response score was >2. CONCLUSIONS: In a normal clinical setting, budesonide CR capsules were well tolerated by patients with ileocecal CD.


Assuntos
Budesonida/uso terapêutico , Doença de Crohn/tratamento farmacológico , Glucocorticoides/uso terapêutico , Adolescente , Adulto , Idoso , Budesonida/administração & dosagem , Budesonida/efeitos adversos , Criança , Qualidade de Produtos para o Consumidor , Preparações de Ação Retardada , Aprovação de Drogas/legislação & jurisprudência , Europa (Continente) , Feminino , Glucocorticoides/administração & dosagem , Glucocorticoides/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
12.
Structure ; 7(1): 35-42, 1999 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-10368271

RESUMO

BACKGROUND: DNA ligases catalyse phosphodiester bond formation between adjacent bases in nicked DNA, thereby sealing the nick. A key step in the catalytic mechanism is the formation of an adenylated DNA intermediate. The adenyl group is derived from either ATP (in eucaryotes and archaea) or NAD+4 (in bacteria). This difference in cofactor specificity suggests that DNA ligase may be a useful antibiotic target. RESULTS: The crystal structure of the adenylation domain of the NAD+-dependent DNA ligase from Bacillus stearothermophilus has been determined at 2.8 A resolution. Despite a complete lack of detectable sequence similarity, the fold of the central core of this domain shares homology with the equivalent region of ATP-dependent DNA ligases, providing strong evidence for the location of the NAD+-binding site. CONCLUSIONS: Comparison of the structure of the NAD+4-dependent DNA ligase with that of ATP-dependent ligases and mRNA-capping enzymes demonstrates the manifold utilisation of a conserved nucleotidyltransferase domain within this family of enzymes. Whilst this conserved core domain retains a common mode of nucleotide binding and activation, it is the additional domains at the N terminus and/or the C terminus that provide the alternative specificities and functionalities in the different members of this enzyme superfamily.


Assuntos
Trifosfato de Adenosina/metabolismo , DNA Ligases/química , DNA Ligases/metabolismo , Geobacillus stearothermophilus/enzimologia , NAD/metabolismo , Dobramento de Proteína , Sequência de Aminoácidos , Sítios de Ligação , Clonagem Molecular , Cristalografia por Raios X , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Secundária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Especificidade por Substrato
13.
Structure ; 7(3): 255-64, 1999 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-10368295

RESUMO

BACKGROUND: Human lung surfactant protein D (hSP-D) belongs to the collectin family of C-type lectins and participates in the innate immune surveillance against microorganisms in the lung through recognition of carbohydrate ligands present on the surface of pathogens. The involvement of this protein in innate immunity and the allergic response make it the subject of much interest. RESULTS: We have determined the crystal structure of a trimeric fragment of hSP-D at 2.3 A resolution. The structure comprises an alpha-helical coiled-coil and three carbohydrate-recognition domains (CRDs). An interesting deviation from symmetry was found in the projection of a single tyrosine sidechain into the centre of the coiled-coil; the asymmetry of this residue influences the orientation of one of the adjacent CRDs. The cleft between the three CRDs presents a large positively charged surface. CONCLUSIONS: The fold of the CRD of hSP-D is similar to that of the mannan-binding protein (MBP), but its orientation relative to the alpha-helical coiled-coil region differs somewhat to that seen in the MBP structure. The novel central packing of the tyrosine sidechain within the coiled-coil and the resulting asymmetric orientation of the CRDs has unexpected functional implications. The positively charged surface might facilitate binding to negatively charged structures, such as lipopolysaccharides.


Assuntos
Glicoproteínas/química , Conformação Proteica , Surfactantes Pulmonares/química , Sequência de Aminoácidos , Sítios de Ligação , Cálcio/química , Cristalografia por Raios X , Humanos , Lectinas , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Secundária de Proteína , Proteína D Associada a Surfactante Pulmonar , Proteínas Recombinantes de Fusão/química , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
14.
J Mol Biol ; 228(4): 1212-8, 1992 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-1474587

RESUMO

The three-dimensional structure of a complex between catalytically active cobalt(II) substituted human carbonic anhydrase II and its substrate bicarbonate was determined by X-ray crystallography (1.9 A). One water molecule and two bicarbonate oxygen atoms are found at distances between 2.3 and 2.5 A from the cobalt ion in addition to the three histidyl ligands contributed by the peptide chain. The tetrahedral geometry around the metal ion in the native enzyme with a single water molecule 2.0 A from the metal is therefore lost. The geometry is difficult to classify but might best be described as distorted octahedral. The structure is suggested to represent a water-bicarbonate exchange state relevant also for native carbonic anhydrase, where the two unprotonized oxygen atoms of the substrate are bound in a carboxylate binding site and the hydroxyl group is free to move closer to the metal thereby replacing the metal-bound water molecule. A reaction mechanism based on crystallographically determined enzyme-ligand complexes is represented.


Assuntos
Bicarbonatos/química , Anidrases Carbônicas/química , Cobalto/química , Bicarbonatos/metabolismo , Anidrases Carbônicas/metabolismo , Cristalização , Esterases/análise , Histidina/química , Humanos , Modelos Moleculares , Oxigênio/química , Conformação Proteica , Especificidade por Substrato , Água/química , Difração de Raios X
15.
J Mol Biol ; 227(4): 1192-204, 1992 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-1433293

RESUMO

In order to obtain a better structural framework for understanding the catalytic mechanism of carbonic anhydrase, a number of inhibitor complexes of the enzyme were investigated crystallographically. The three-dimensional structure of free human carbonic anhydrase II was refined at pH 7.8 (1.54 A resolution) and at pH 6.0 (1.67 A resolution). The structure around the zinc ion was identical at both pH values. The structure of the zinc-free enzyme was virtually identical with that of the native enzyme, apart from a water molecule that had moved 0.9 A to fill the space that would be occupied by the zinc ion. The complexes with the anionic inhibitors bisulfite and formate were also studied at neutral pH. Bisulfite binds with one of its oxygen atoms, presumably protonized, to the zinc ion and replaces the zinc water. Formate, lacking a hydroxyl group, is bound with its oxygen atoms not far away from the position of the non-protonized oxygen atoms of the bisulfite complex, i.e. at hydrogen bond distance from Thr199 N and at a position between the zinc ion and the hydrophobic part of the active site. The result of these and other studies have implications for our view of the catalytic function of the enzyme, since virtually all inhibitors share some features with substrate, product or expected transition states. A reaction scheme where electrophilic activation of carbon dioxide plays an important role in the hydration reaction is presented. In the reverse direction, the protonized oxygen of the bicarbonate is forced upon the zinc ion, thereby facilitating cleavage of the carbon-oxygen bond. This is achieved by the combined action of the anionic binding site, which binds carboxyl groups, the side-chain of threonine 199, which discriminates between hydrogen bond donors and acceptors, and hydrophobic interaction between substrate and the active site cavity. The required proton transfer between the zinc water and His64 can take place through water molecules 292 and 318.


Assuntos
Anidrases Carbônicas/química , Ânions , Sítios de Ligação , Inibidores da Anidrase Carbônica/metabolismo , Anidrases Carbônicas/metabolismo , Catálise , Cianatos/química , Formiatos/química , Humanos , Ligação de Hidrogênio , Ligantes , Conformação Proteica , Sulfitos/química , Temperatura , Difração de Raios X
16.
Parkinsonism Relat Disord ; 11 Suppl 1: S25-9, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15885624

RESUMO

Involuntary movements, or dyskinesia, represent a debilitating complication of levodopa therapy for Parkinson's disease. Taking advantage of a monkey brain bank constituted to study the pathophysiology of levodopa-induced dyskinesia, we here report the changes affecting D1, D2 and D3 dopamine receptors within the striatum of four experimental groups of non-human primates: normal, parkinsonian, parkinsonian treated with levodopa without or with dyskinesia. We also report the possible role of arrestin and G protein-coupled receptor kinases.


Assuntos
Antiparkinsonianos/efeitos adversos , Discinesia Induzida por Medicamentos/etiologia , Levodopa/efeitos adversos , Doença de Parkinson/tratamento farmacológico , Receptores de Dopamina D1/fisiologia , Receptores de Dopamina D2/fisiologia , Discinesia Induzida por Medicamentos/fisiopatologia , Humanos , Doença de Parkinson/fisiopatologia , Receptores de Dopamina D3
17.
Neuromuscul Disord ; 25(5): 414-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25795140

RESUMO

In patients with myotonic dystrophy type 1 overweight and obesity are frequent. When present this has further negative effects on the patients' pulmonary and muscle function as well as social participation. Anesthesia in myotonic dystrophy type 1 patients is associated with increased risks, especially in those who are obese. We describe the outcome of the first patient reported who has undergone gastric bypass surgery. The operation went without complications. Within two years after surgery she has lost 56.5 kg corresponding to 44% of her preoperative body weight (128.5 kg). She has lost muscle mass and muscle strength, but has gained somewhat in functional tests including pulmonary function and has no longer any need for nocturnal ventilation. Surgical treatment of obesity may be feasible in selected myotonic dystrophy type 1 patients but further studies are needed to determine appropriate criteria for surgery including body mass index limits and how pre- and post-operative follow-up should best be made.


Assuntos
Distrofia Miotônica/cirurgia , Obesidade/cirurgia , Adulto , Peso Corporal , Feminino , Derivação Gástrica , Humanos , Distrofia Miotônica/complicações , Obesidade/complicações , Resultado do Tratamento
18.
Mucosal Immunol ; 8(3): 545-58, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25269704

RESUMO

Mucosal tissues contain large numbers of memory CD4(+) T cells that, through T-cell receptor-dependent interactions with antigen-presenting cells, are believed to have a key role in barrier defense and maintenance of tissue integrity. Here we identify a major subset of memory CD4(+) T cells at barrier surfaces that coexpress interleukin-18 receptor alpha (IL-18Rα) and death receptor-3 (DR3), and display innate lymphocyte functionality. The cytokines IL-15 or the DR3 ligand tumor necrosis factor (TNF)-like cytokine 1A (TL1a) induced memory IL-18Rα(+)DR3(+)CD4(+) T cells to produce interferon-γ, TNF-α, IL-6, IL-5, IL-13, granulocyte-macrophage colony-stimulating factor (GM-CSF), and IL-22 in the presence of IL-12/IL-18. TL1a synergized with IL-15 to enhance this response, while suppressing IL-15-induced IL-10 production. TL1a- and IL-15-mediated cytokine induction required the presence of IL-18, whereas induction of IL-5, IL-13, GM-CSF, and IL-22 was IL-12 independent. IL-18Rα(+)DR3(+)CD4(+) T cells with similar functionality were present in human skin, nasal polyps, and, in particular, the intestine, where in chronic inflammation they localized with IL-18-producing cells in lymphoid aggregates. Collectively, these results suggest that human memory IL-18Rα(+)DR3(+) CD4(+) T cells may contribute to antigen-independent innate responses at barrier surfaces.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Doença de Crohn/imunologia , Imunidade Inata , Pólipos Nasais/imunologia , Receptores de Interleucina-18/imunologia , Membro 25 de Receptores de Fatores de Necrose Tumoral/imunologia , Linfócitos T CD4-Positivos/patologia , Doença de Crohn/genética , Doença de Crohn/patologia , Células Epiteliais/imunologia , Células Epiteliais/patologia , Regulação da Expressão Gênica , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Humanos , Imunidade nas Mucosas , Memória Imunológica , Interferon gama/genética , Interferon gama/imunologia , Interleucina-13/genética , Interleucina-13/imunologia , Interleucina-15/genética , Interleucina-15/imunologia , Interleucina-5/genética , Interleucina-5/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Interleucinas/genética , Interleucinas/imunologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Pólipos Nasais/genética , Pólipos Nasais/patologia , Cultura Primária de Células , Receptores de Interleucina-18/genética , Membro 25 de Receptores de Fatores de Necrose Tumoral/genética , Transdução de Sinais , Pele/citologia , Pele/imunologia , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/imunologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Interleucina 22
19.
Protein Sci ; 9(9): 1607-17, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11045608

RESUMO

Collectins are animal calcium dependent lectins that target the carbohydrate structures on invading pathogens, resulting in the agglutination and enhanced clearance of the microorganism. These proteins form trimers that may assemble into larger oligomers. Each polypeptide chain consists of four regions: a relatively short N-terminal region, a collagen like region, an alpha-helical coiled-coil, and the lectin domain. Only primary structure data are available for the N-terminal region, while the most important features of the collagen-like region can be derived from its homology with collagen. The structures of the alpha-helical coiled-coil and the lectin domain are known from crystallographic studies of mannan binding protein (MBP) and lung surfactant protein D (SP-D). Carbohydrate binding has been structurally characterized in several complexes between MBP and carbohydrate; all indicate that the major interaction between carbohydrate and collectin is the binding of two adjacent carbohydrate hydroxyl group to a collectin calcium ion. In addition, these hydroxyl groups hydrogen bond to some of the calcium amino acid ligands. While each collectin trimer contains three such carbohydrate binding sites, deviation from the overall threefold symmetry has been demonstrated for SP-D, which may influence its binding properties. The protein surface between the three binding sites is positively charged in both MBP and SP-D.


Assuntos
Proteínas de Transporte/química , Sequência de Aminoácidos , Colectinas , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Homologia de Sequência de Aminoácidos
20.
FEBS Lett ; 350(2-3): 319-22, 1994 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-8070585

RESUMO

It has recently been shown that aliphatic sulphonamides are good inhibitors of carbonic anhydrase (CA) provided that the pK of the sulphonamide is low. We have determined the structure of the complex between CAII and CF3SO2NH2 by X-ray crystallographic methods. The nitrogen of the sulphonamide is bound to the zinc ion of the enzyme in the usual manner. The other parts of the inhibitor show a different mode of binding from aromatic sulphonamides since the trifluoromethyl group is bound at the hydrophobic part of the active site instead of pointing out from the active site. It should be possible to design new inhibitors specific for the different isoenzymes, starting from the present structure.


Assuntos
Inibidores da Anidrase Carbônica/química , Anidrases Carbônicas/química , Sulfonamidas/química , Sítios de Ligação , Clorofluorcarbonetos de Metano/química , Cristalografia por Raios X , Humanos , Modelos Moleculares
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