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1.
Ann Hematol ; 103(7): 2347-2354, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38771499

RESUMO

Ropeginterferon-alfa2b (ropegIFNα2b) is a long-acting IFN formulation with broad FDA/EMA approval as a therapy of polycythemia vera (PV) with no symptomatic splenomegaly. There is currently lack of information on the real-world patient selection, including the impact of local reimbursement policies, and drug management, particularly: type/timing of screening and follow-up tests; absolute/relative contraindications to therapy; ropegIFNα2b dose and combinations with hydroxyurea. As a sub-analysis of the PV-ARC retrospective study (NCT06134102), we here report our monocenter experience with ropegIFNα2b in the period from January 2021, corresponding to drug availability outside clinical trial, and December 2023. Among the 149 patients with EMA/FDA indication, only 55 (36.9%) met the local reimbursement criteria and 18 (12.1%) received ropegIFNα2b. Thanks to appropriate screening, relative/absolute contraindications to ropegIFNα2b were detected and managed in a multidisciplinary manner. Efficacy and safety of ropegIFNα2b was confirmed, with 3 cases of early molecular response. General use of low ropegIFNα2b dose, with frequent need for hydroxyurea combinations, was noted. This real-world experience suggests a significant impact of local regulations on drug prescription and the need for greater real-world data collection on ropegIFNα2b in PV patients. Also, it describes appropriate multidisciplinary screening and monitoring procedures during ropegIFNα2b therapy.


Assuntos
Interferon alfa-2 , Interferon-alfa , Policitemia Vera , Polietilenoglicóis , Proteínas Recombinantes , Humanos , Policitemia Vera/tratamento farmacológico , Interferon-alfa/uso terapêutico , Interferon-alfa/administração & dosagem , Polietilenoglicóis/uso terapêutico , Polietilenoglicóis/administração & dosagem , Proteínas Recombinantes/uso terapêutico , Interferon alfa-2/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Feminino , Idoso , Seleção de Pacientes , Resultado do Tratamento , Adulto , Hidroxiureia/uso terapêutico , Hidroxiureia/administração & dosagem
2.
Int Endod J ; 53(2): 186-199, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31162683

RESUMO

AIM: To reach a consensus on a consistent strategy to adopt when screening patients for dental/periodontal infections and on the feasibility of providing dental treatment before cardiothoracic surgery, cardiovascular surgery or other cardiovascular invasive procedures. METHODOLOGY: A panel of experts from six Italian scientific societies was created. The deliberations of the panel were based on the RAND method. From an initial systematic literature review, it became clear that a consensually validated protocol for the reproducible dental screening of patients awaiting cardiac interventions was considered mandatory by professionals with expertise in the dental, cardiologic and cardiac surgery areas. However, a systematic review also concluded that the treatment options to be provided, their prognosis and timing in relation to the physical condition of patients, had never been defined. Following the systematic review, several fundamental questions were generated. The panel was divided into two working groups each of which produced documents that addressed the topic and which were subsequently used to generate a questionnaire. Each member of the panel completed the questionnaire independently, and then, a panel discussion was held to reach a consensus on how best to manage patients with dental/periodontal infections who were awaiting invasive cardiac procedures. RESULTS: A high level of agreement was reached regarding all the items on the questionnaire, and each of the clinical questions formulated were answered. Three tables were created which can be used to generate a useful tool to provide standardized dental/periodontal screening of patients undergoing elective cardiovascular interventions and to summarize both the possible oral and cardiovascular conditions of the patient and the timing available for the procedures considered. CONCLUSIONS: Upon publication of this consensus document, the dissemination of the information to a wide dental and cardiac audience should commence. The authors hope that this consensus will become a model for the development of a dedicated protocol, ideally usable by heart and dental teams in the pre-interventional preparation phase.


Assuntos
Procedimentos Cirúrgicos Cardiovasculares , Doenças Periodontais , Doenças Estomatognáticas , Procedimentos Cirúrgicos Torácicos , Consenso , Humanos , Infecções , Doenças Periodontais/diagnóstico , Cuidados Pré-Operatórios , Doenças Estomatognáticas/diagnóstico
3.
Clin Exp Dermatol ; 42(5): 532-535, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28543394

RESUMO

Bullous morphoea is a rare variant of localized scleroderma whose pathogenesis has been widely discussed. We retrospectively reviewed the records of all histopathologically confirmed cases of morphoea followed from 2005 to 2015 at the Dermatology Clinic and Pathology Institute of the University of Cagliari, Sardinia, Italy. Among 137 patients with morphoea, 2 cases of the bullous variant were identified, which were successfully treated with methotrexate. Thus, the bullous form comprised 1.4% of all cases of morphoea, which is much lower than the 7.5% previously reported. In one of the cases, histopathological examination revealed a peculiar 'stretching' pattern of basal keratinocytes attached to the epidermal roof of the bulla, together with increased lymphatic vessels, which were either collapsed or dilated, stressing the role of lymphatics and possibly of excessive skin trauma and friction in the development of bullous lesions.


Assuntos
Vesícula/etiologia , Fármacos Dermatológicos/uso terapêutico , Metotrexato/uso terapêutico , Esclerodermia Localizada/patologia , Idoso , Idoso de 80 Anos ou mais , Vesícula/patologia , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Doenças Raras , Estudos Retrospectivos , Esclerodermia Localizada/complicações , Esclerodermia Localizada/tratamento farmacológico
4.
G Ital Dermatol Venereol ; 149(3): 363-6, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24819765

RESUMO

Tazarotene is a topically-applied, receptor-selective retinoid that has been shown to modulate several major pathogenic factors of psoriasis. Adverse effects are those of topical application of retinoids, the most common being mild to moderate burning, itching, stinging, and erythema, due to mild to moderate local skin irritation. While pyogenic granuloma-like lesions are a well recognized side effects of systemic retinoids, to our knowledge in the literature there is only one reported case of pyogenic granuloma (PG) following topical application of tazarotene for scalp psoriasis. In this paper we report 2 cases of periungual PGs following application of topical tazarotene and we present a review of the literature.


Assuntos
Fármacos Dermatológicos/efeitos adversos , Granuloma Piogênico/induzido quimicamente , Doenças da Unha/tratamento farmacológico , Ácidos Nicotínicos/efeitos adversos , Psoríase/tratamento farmacológico , Administração Cutânea , Adulto , Idoso , Fármacos Dermatológicos/administração & dosagem , Feminino , Humanos , Masculino , Doenças da Unha/etiologia , Ácidos Nicotínicos/administração & dosagem , Psoríase/complicações
5.
G Ital Dermatol Venereol ; 149(2): 177-84, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24819637

RESUMO

AIM: In the literature, clinical features of psoriasis associated with psoriatic arthritis (PsA) onset have not been clarified, even if high Psoriasis Area and Severity Index (PASI) was found to be directly related with PsA. METHODS: The study was conducted between November 2008 and April 2009 on consecutive psoriatic outpatients referred to a service of dermatological consultations, on indication of other hospital specialists. Participants were affected by mild skin psoriasis, in particular with nail dystrophies and/or scalp and/or intergluteal/perianal lesions. The questionnaire provided by the Classification of Psoriatic Arthritis (CASPAR) study group was proposed to all patients and we added a question about the time of psoriasis onset. RESULTS: Eighty-seven subjects (34 males and 53 females) aged between 18 and 91 years (mean age 48 years) with such psoriatic features were recruited. Other 30 refused to take part to the study. Forty-seven per cent of these participants were found to suffer from PsA, in particular 83% of those with nail and scalp psoriasis, 40% of subjects with intergluteal/perianal involvement and 37% of patients with just scalp lesions. We present the first exploratory and observational study focused on a population with mild skin psoriasis, in order to evaluate if nail dystrophies, scalp or intergluteal/perianal psoriatic lesions might be indicative of a higher risk of PsA even in cases with mild skin psoriasis. CONCLUSION: Nail psoriasis is probably a suggestive feature of joint involvement. The scalp psoriasis, as well as intergluteal/perianal psoriatic lesions, is likely to be less associated to PsA, but may be an important comorbidity factor for the development of PsA. Further investigations in a larger population are encouraged to assess a potential link between PsA, site-specific and mild skin psoriasis.


Assuntos
Artrite Psoriásica/epidemiologia , Doenças da Unha/epidemiologia , Psoríase/epidemiologia , Dermatoses do Couro Cabeludo/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Artrite Psoriásica/diagnóstico , Artrite Psoriásica/diagnóstico por imagem , Nádegas/patologia , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças da Unha/patologia , Especificidade de Órgãos , Períneo/patologia , Prevalência , Psoríase/patologia , Radiografia , Fatores de Risco , Dermatoses do Couro Cabeludo/patologia , Pele/patologia , Adulto Jovem
6.
Colorectal Dis ; 14(5): 616-22, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21801294

RESUMO

AIM: With the aim of reducing recurrence after perineal surgery for full-thickness rectal prolapse, a new operation consisting of a trans-obturator colonic suspension during Altemeier's operation has been developed. METHOD: Eighteen women with full-thickness rectal prolapse were examined clinically, with validated quality of life and continence scores, colonoscopy, anorectal manometry, anal EMG and sacral reflex latency. Ten had a newly diagnosed and eight a recurrent prolapse. The Altemeier operation was combined with a levatorplasty in all cases using two porcine collagen prostheses sutured to the descending colon and passed through the trans-obturator space bilaterally. The operation was completed by a manual or stapled colo-anal anastomosis. Clinical examination, with quality of life and continence scores, anorectal manometry, EMG and sacral reflex latency, was scheduled during follow up, with the recurrence of prolapse as the primary outcome measure. RESULTS: There were no recurrences at 30 months. There was no mortality and no complications. All patients experienced significant improvement in quality of life and faecal continence scores (P<0.01). Surgery did not affect anorectal pressures or sacral reflex latencies. CONCLUSION: The new technique appears to be relatively easy to perform and is complication free with no recurrence after a short period of follow up. A larger study with appropriate controls and longer follow up is now needed to assess its real effectiveness in reducing the risk of recurrence.


Assuntos
Canal Anal/cirurgia , Colo/cirurgia , Prolapso Retal/cirurgia , Slings Suburetrais , Adulto , Idoso , Idoso de 80 Anos ou mais , Canal Anal/fisiopatologia , Anastomose Cirúrgica/efeitos adversos , Distribuição de Qui-Quadrado , Eletromiografia , Incontinência Fecal/etiologia , Feminino , Humanos , Manometria , Pessoa de Meia-Idade , Qualidade de Vida , Prolapso Retal/complicações , Prevenção Secundária , Estatísticas não Paramétricas , Slings Suburetrais/efeitos adversos
8.
Int J Cardiol ; 292: 78-86, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31262607

RESUMO

AIM: To reach a consensus on a consistent strategy to adopt when screening patients for dental/periodontal infections, and on the feasibility of providing dental treatment before cardiothoracic surgery, cardiovascular surgery or other cardiovascular invasive procedures. METHODOLOGY: A panel of experts from six Italian scientific societies was created. The deliberations of the panel were based on the RAND method. From an initial systematic literature review, it became clear that a consensually validated protocol for the reproducible dental screening of patients awaiting cardiac interventions was considered mandatory by professionals with expertise in the dental, cardiologic and cardiac surgery areas. However, systematic review also concluded that the treatment options to be provided, their prognosis and timing in relation to the physical condition of patients had never been defined. Following the systematic review several fundamental questions were generated. The panel was divided into two working groups each of which produced documents that addressed the topic and which were subsequently used to generate a questionnaire. Each member of the panel completed the questionnaire independently and then a panel discussion was held to reach a consensus on how best to manage patients with dental/periodontal infections who were awaiting invasive cardiac procedures. RESULTS: A high level of agreement was reached regarding all the items on the questionnaire, and each of the clinical questions formulated were answered. Three tables were created which can be used to generate a useful tool to provide standardized dental/periodontal screening of patients undergoing elective cardiovascular interventions, and to summarize both the possible oral and cardiovascular conditions of the patient and the timing available for the procedures considered. CONCLUSIONS: Upon publication of this consensus document, the dissemination of the information to a wide dental and cardiac audience should commence. The authors hope that this consensus can become a model for the development of a dedicated protocol, ideally usable by heart and dental teams in the pre-interventional preparation phase.


Assuntos
Procedimentos Cirúrgicos Cardiovasculares , Doenças Periodontais/diagnóstico , Doenças Periodontais/terapia , Cuidados Pré-Operatórios/normas , Sepse/diagnóstico , Sepse/terapia , Doenças Estomatognáticas/diagnóstico , Doenças Estomatognáticas/terapia , Procedimentos Cirúrgicos Torácicos , Técnica Delphi , Humanos , Programas de Rastreamento , Doenças Periodontais/microbiologia , Período Pré-Operatório , Doenças Estomatognáticas/microbiologia , Inquéritos e Questionários
9.
Sci Total Environ ; 645: 837-853, 2018 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-30248882

RESUMO

The Platani River flowing in south-central Sicily, interacting with evaporite rocks, generates a wide range of ionic strength in the water catchment from 0.1 to 5.0molkg-1. We sampled 38 river sites and analysed the composition for the dissolved fraction filtered through 0.45µm, the truly dissolved fraction obtained through ultrafiltration (10kDa) and the relative included colloidal fraction. This study was focused on the recognition of Zr, Hf and REE behaviour under changing ionic strength conditions, since this is one of parameters responsible for colloid stability in natural waters. In turn, this phenomenon leads to REE release from the colloidal fraction and their scavenging onto surfaces of suspended particles or sediment, or their complexation with dissolved ligands. Our results indicated that in both dissolved and ultra-filtrated fractions REE increases either in the middle (Sm - Dy) or in the heavier (Ho - Lu) part of the PAAS-normalised distribution, while the Zr/Hf ratio value ranges from sub-chondritic to super-chondritic. Scanning Electron Microscopic and Energy Dispersive X-ray Spectrometric (SEM-EDS) analyses and dissolved Mg, Al and Fe concentrations suggested that the studied colloids consist of aggregations of Al-oxyhydroxides, carbonate nanoparticles and clays where organic traces were not found. The studied colloids showed greater affinity with dissolved Zr than Hf determining Zr/Hf values larger than the chondritic values. The largest Zr/Hf values were found in colloidal fractions from waters with ionic strength larger than 0.6molkg-1. These Zr/Hf values up to 280 (w/w) are provided by the faster removal of Hf relative to Zr from coagulating colloids and its preferential scavenging onto authigenic Fe-oxyhydroxides in bottom sediment. Further studies are needed to clarify is this suggested process can represent a suitable starting point for the Zr-Hf decoupling observed in seawater.

10.
Int J Tuberc Lung Dis ; 11(6): 703-5, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17519105

RESUMO

To achieve tuberculosis (TB) control, National Tuberculosis Programme guidelines should be implemented effectively. In a survey conducted in 2005-2006, 33 Brazilian medical school coordinators answered a questionnaire about TB education. The median time dedicated to TB was 27 h (4-119 h), spread over several disciplines, mainly biological and clinical. This included 12 h (0-88 h) of practical activities, mainly in university hospitals (53%). The recommendation to offer human immunodeficiency virus testing for TB patients was taught in only 54% of the schools. TB education in Brazil is fragmented and restricted to a biological approach, while field activities are insufficient and carried out in inadequate settings. Important changes to the TB curriculum are necessary.


Assuntos
Educação de Graduação em Medicina , Faculdades de Medicina , Tuberculose , Atitude do Pessoal de Saúde , Brasil/epidemiologia , Controle de Doenças Transmissíveis , Currículo , Educação de Graduação em Medicina/estatística & dados numéricos , Guias como Assunto , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Programas Nacionais de Saúde , Faculdades de Medicina/estatística & dados numéricos , Inquéritos e Questionários , Ensino/métodos , Fatores de Tempo , Tuberculose/epidemiologia , Tuberculose/prevenção & controle , Tuberculose/terapia
11.
Biochim Biophys Acta ; 1709(3): 240-50, 2005 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-16139785

RESUMO

The Na+/H+ antiporter NhaA is the main Na+ extrusion system in E. coli. Using direct current measurements combined with a solid supported membrane (SSM), we obtained electrical data of the function of NhaA purified and reconstituted in liposomes. These measurements demonstrate NhaA's electrogenicity, its specificity for Li+ and Na+ and its pronounced pH dependence in the range pH 6.5-8.5. The mutant G338S, in contrast, presents a pH independent profile, as reported previously. A complete right-side-out orientation of the NhaA antiporter within the proteoliposomal membrane was determined using a NhaA-specific antibody based ELISA assay. This allowed for the first time the investigation of NhaA in the passive downhill uptake mode corresponding to the transport of Na+ from the periplasmic to the cytoplasmic side of the membrane. In this mode, the transporter has kinetic properties differing significantly from those of the previously investigated efflux mode. The apparent Km values were 11 mM for Na+ and 7.3 mM for Li+ at basic pH and 180 mM for Na+ and 50 mM for Li+ at neutral pH. The data demonstrate that in the passive downhill uptake mode pH regulation of the carrier affects both apparent Km as well as turnover (Vmax).


Assuntos
Proteínas de Escherichia coli/metabolismo , Escherichia coli/metabolismo , Trocadores de Sódio-Hidrogênio/metabolismo , Anticorpos Monoclonais/metabolismo , Transporte Biológico Ativo/fisiologia , Eletrofisiologia , Ensaio de Imunoadsorção Enzimática , Epitopos/genética , Proteínas de Escherichia coli/genética , Concentração de Íons de Hidrogênio , Transporte de Íons/fisiologia , Cinética , Lipossomos , Mutação/genética , Sódio/metabolismo , Trocadores de Sódio-Hidrogênio/genética , Espectrometria de Fluorescência
12.
Biochim Biophys Acta ; 1505(1): 144-57, 2001 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11248196

RESUMO

Na(+)/H(+) antiporters are membrane proteins that play a major role in pH and Na(+) homeostasis of cells throughout the biological kingdom, from bacteria to humans and higher plants. The emerging genomic sequence projects already have started to reveal that the Na(+)/H(+) antiporters cluster in several families. Structure and function studies of a purified antiporter protein have as yet been conducted mainly with NhaA, the key Na(+)/H(+) antiporter of Escherichia coli. This antiporter has been overexpressed, purified and reconstituted in a functional form in proteoliposomes. It has recently been crystallized in both 3D as well as 2D crystals. The NhaA 2D crystals were analyzed by cryoelectron microscopy and a density map at 4 A resolution was obtained and a 3D map was reconstructed. NhaA is shown to exist in the 2D crystals as a dimer of monomers each composed of 12 transmembrane segments with an asymmetric helix packing. This is the first insight into the structure of a polytopic membrane protein. Many Na(+)/H(+) antiporters are characterized by very dramatic sensitivity to pH, a property that corroborates their role in pH homeostasis. The molecular mechanism underlying this pH sensitivity has been studied in NhaA. Amino acid residues involved in the pH response have been identified. Conformational changes transducing the pH change into a change in activity were found in loop VIII-IX and at the N-terminus by probing trypsin digestion or binding of a specific monoclonal antibody respectively. Regulation by pH of the eukaryotic Na(+)/H(+) antiporters involves an intricate signal transduction pathway (recently reviewed by Yun et al., Am. J. Physiol. 269 (1995) G1-G11). The transcription of NhaA has been shown to be regulated by a novel Na(+)-specific regulatory network. It is envisaged that interdisciplinary approaches combining structure, molecular and cell biology as well as genomics should be applied in the future to the study of this important group of transporters.


Assuntos
Proteínas de Bactérias/metabolismo , Proteínas de Escherichia coli , Escherichia coli/metabolismo , Trocadores de Sódio-Hidrogênio/metabolismo , Sódio/metabolismo , Sequência de Aminoácidos , Animais , Cátions Monovalentes , Regulação da Expressão Gênica , Humanos , Concentração de Íons de Hidrogênio , Modelos Genéticos , Dados de Sequência Molecular , Filogenia , Plantas , Conformação Proteica , Transdução de Sinais , Trocadores de Sódio-Hidrogênio/química , Trocadores de Sódio-Hidrogênio/genética , Transcrição Gênica
13.
Curr Opin Chem Biol ; 1(4): 506-13, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9667884

RESUMO

The development of supramolecular chemistry has allowed the construction of structurally organized and functionally integrated chemical systems capable of elaborating the energy and information input of photons to perform complex functions. Model systems capable of mimicking the two fundamental steps of photosynthesis, namely light harvesting and photoinduced charge separation, have recently been developed.


Assuntos
Fotoquímica , Fotossíntese , Configuração de Carboidratos , Química Orgânica/métodos , Ciclodextrinas/química , Transferência de Energia , Luz , Modelos Químicos , Modelos Moleculares , Conformação Molecular , Oxirredução , Luz Solar , Água
14.
Eur J Phys Rehabil Med ; 51(1): 59-69, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24476805

RESUMO

BACKGROUND: Robotics and related technologies are realizing their promise to improve the delivery of rehabilitation therapy but the mechanism by which they enhance recovery is still unknown. The electromechanical-driven gait orthosis Lokomat has demonstrated its utility for gait rehabilitation after stroke. AIM: To test the efficacy of Lokomat in gait retraining and to investigate the neurophysiological mechanisms underlying the recovery process. DESIGN: Case series study. SETTING: Unit of Neurorehabilitation of a University Hospital. POPULATION: Fifteen patients with post-stroke hemiparesis. METHODS: Patients underwent a six weeks rehabilitative treatment provided by Lokomat. The outcome measures were: Fugl-Meyer Motor Scale (FMMS), Berg Balance Scale (BBS), 10 metres Walking Test (10mWT), Timed Up and Go test (TUG), 6 Minute Walking Test (6MWT). Strength and Motor Unit firing rate of vastus medialis (VM) were analyzed during isometric knee extension through an isokinetic dynamometer and surface EMG recording. RESULTS: An increase of duration and covered distance, a decrease of body weight support and guidance force on the paretic side along the sessions were observed. The FMMS, the BBS, the TUG and the 6MWT demonstrated a significant improvement after the training. No increase of force was observed whereas a significant increase of firing rate of VM was recorded. CONCLUSION: The evidence that the improvement of walking ability observed in our study determines a significant increase of firing rate of VM not accompanied by an increase of force could suggest an effect of training on motorneuronal firing rate that thus contributes to improve motor control. CLINICAL REHABILITATION IMPACT: Given the current wide use of robotics in gait retraining after stroke, our approach can contribute to clarify the mechanisms underlying its rehabilitative impact so as to incorporate the findings of evidence-based practice into appropriate treatment plans for persons poststroke.


Assuntos
Terapia por Exercício/métodos , Marcha , Neurônios Motores/fisiologia , Robótica , Reabilitação do Acidente Vascular Cerebral , Adulto , Idoso , Idoso de 80 Anos ou mais , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Aparelhos Ortopédicos , Paresia/reabilitação
15.
FEBS Lett ; 441(1): 53-8, 1998 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-9877164

RESUMO

Monoclonal antibodies (mAbs) recognizing native epitopes are an important tool for functional and structural studies of proteins, yet they have rarely been used with transport proteins. In an attempt to raise monoclonal antibodies against the NhaA Na+/H+ antiporter of Escherichia coli we encountered difficulties in the screening procedure, which is based on the standard enzyme-linked immunosorbent assay (ELISA). Here we report a rapid and efficient method of screening for anti-NhaA mAbs which recognize native epitopes of the antiporter. The method is based on the use of His-tagged protein, Ni2+-nitrilotriacetic acid coated plates and non-denaturing conditions in the assay. With this procedure four mAbs were obtained, three of which recognize the NhaA in its native conformation and one preferentially recognizes the denatured form. The latter mAb is Western blot positive, the others are Western blot negative and bind the detergent solubilized NhaA as assayed by gel filtration chromatography. Competition experiments show that the native epitopes are common to both the His-tagged and the wild-type protein. We suggest that in the standard ELISA the NhaA protein is not presented to the antibody in the native conformation whereas the His tag based protocol favors this presentation. Indeed, we could remarkably improve the low reactivity of the standard ELISA by coating the plates with anti-NhaA mAb and use it to present NhaA ('sandwich' ELISA or two antibodies assay). Remarkably, two of the mAbs (5H4, 2C5) which bind native NhaA inhibit drastically the deltapH driven 22Na uptake mediated by His-tagged NhaA reconstituted in proteoliposomes. Hence, these mAbs afford a new tool to study the structure/function relationship of the antiporter.


Assuntos
Anticorpos Monoclonais , Epitopos/análise , Proteínas de Escherichia coli , Escherichia coli/metabolismo , Trocadores de Sódio-Hidrogênio/análise , Trocadores de Sódio-Hidrogênio/imunologia , Animais , Anticorpos Monoclonais/isolamento & purificação , Proteínas de Bactérias/análise , Proteínas de Bactérias/imunologia , Western Blotting , Cromatografia em Gel , Ensaio de Imunoadsorção Enzimática , Feminino , Imunoglobulina G , Cadeias kappa de Imunoglobulina , Lipossomos , Camundongos , Camundongos Endogâmicos BALB C , Proteolipídeos
16.
Am J Clin Nutr ; 66(5): 1277-82, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9356548

RESUMO

Several epidemiologic studies have suggested that dairy product intake is associated with a decreased incidence of colon cancer. To determine whether the cytotoxicity and genotoxicity of the aqueous portion of human stool (two potential risk markers for the disease) were affected by a change in dairy product intake, 18 healthy male and female volunteers were randomly divided into two groups. In a crossover design, the volunteers shifted from their normal dairy product-rich diet to a dairy product-free diet. Nutritional analysis of the food consumed during the study period showed a significant decrease in energy intake from 9000 to 7866 kJ/d because of a decreased intake of protein and fat. Carbohydrate and fiber intakes remained unchanged during the intervention. Calcium intake decreased significantly from 1488 to 372 mg/d, with similar significant decreases in phosphate and vitamin D intakes. Cytotoxicity of fecal water, analyzed by the HT-29 cytotoxicity assay, indicated a significant decrease in cell survival from 34% to 20% when dairy products were excluded from the participants' diets. Single-cell gel electrophoresis (COMET assay), used to analyze genotoxicity of fecal waters, indicated no differences brought about by the dietary intervention. In conclusion, our findings indicate that a shift from a dairy product-rich to a dairy product-free diet resulted in a significant effect on an accepted risk marker for colon cancer and may suggest that the mechanism by which dairy products are protective is at the level of tumor promotion rather than initiation.


Assuntos
Neoplasias do Colo/etiologia , Laticínios , Dieta , Fezes/química , Adulto , Água Corporal/metabolismo , Neoplasias do Colo/prevenção & controle , Estudos Cross-Over , Citotoxinas/isolamento & purificação , Eletroforese , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutagênicos/isolamento & purificação , Fatores de Risco
17.
Biomaterials ; 25(15): 2933-40, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-14967525

RESUMO

Mesoporous carbons derived from two types of sulphonated styrene divinylbenzene copolymers (Macronet MN500HS and CT275, Purolite International Ltd) were produced and their adsorptive capacity for the proinflammatory cytokine IL-1 beta (MW 14.4 kDa) determined. The carbons produced had surface areas from 400 to 1200 m(2)g(-1) and pore volume between 0.2 and 1.4 cm(3)g(-1). The mechanical strength of the carbon beads with surface area values up to 800 m(2)g(-1) were robust. The highest adsorption value of IL-1 beta was 150 ng g(-1) for a mesoporous carbon with surface area around 900 m(2)g(-1) and pore volume around 1.3 cm(3)g(-1). However, there was a trade-off between adsorptive capacity and mechanical strength. When used in conjunction with existing treatment modalities, the materials produced have the potential to enhance the removal of uraemic toxins.


Assuntos
Materiais Biocompatíveis/química , Carvão Vegetal/química , Interleucina-1/química , Interleucina-1/isolamento & purificação , Diálise Renal/instrumentação , Ultrafiltração/instrumentação , Adsorção , Carbono/química , Força Compressiva , Citocinas/química , Citocinas/isolamento & purificação , Dureza , Teste de Materiais , Permeabilidade , Porosidade , Propriedades de Superfície
18.
Chemistry ; 6(19): 3558-74, 2000 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-11072822

RESUMO

A molecular-level abacus-like system driven by light inputs has been designed in the form of a [2]rotaxane, comprising the pi-electron-donating macrocyclic polyether bis-p-phenylene-34-crown-10 (BPP34C10) and a dumbbell-shaped component that contains 1) a Ru(II) polypyridine complex as one of its stoppers in the form of a photoactive unit, 2) a p-terphenyl-type ring system as a rigid spacer, 3) a 4,4'-bipyridinium unit and a 3,3'-dimethyl-4,4'-bipyridinium unit as pi-electron-accepting stations, and 4) a tetraarylmethane group as the second stopper. The synthesis of the [2]rotaxane was accomplished in four successive stages. First of all, the dumbbell-shaped component of the [2]rotaxane was constructed by using conventional synthetic methodology to make 1) the so-called "west-side" comprised of the Ru(II) polypyridine complex linked by a bismethylene spacer to the p-terphenyl-type ring system terminated by a benzylic bromomethyl function and 2) the so-called "east-side" comprised of the tetraarylmethane group, attached by a polyether linkage to the bipyridinium unit, itself joined in turn by a trismethylene spacer to an incipient 3,3'-dimethyl-4,4'-bipyridinium unit. Next, 3) the "west-side" and "east-side" were fused together by means of an alkylation to give the dumbbell-shaped compound, which was 4) finally subjected to a thermodynamically driven slippage reaction, with BPP34C10 as the ring, to afford the [2]rotaxane. The structure of this interlocked molecular compound was characterized by mass spectrometry and NMR spectroscopy, which also established, along with cyclic voltammetry, the co-conformational behavior of the molecular shuttle. The stable translational isomer is the one in which the BPP34C10 component encircles the 4,4'-bipyridinium unit, in keeping with the fact that this station is a better pi-electron acceptor than the other station. This observation raises the question- can the BPP34C10 macrocycle be made to shuttle between the two stations by a sequence of photoinduced electron transfer processes? In order to find an answer to this question, the electrochemical, photophysical, and photochemical (under continuous and pulsed excitation) properties of the [2]rotaxane, its dumbbell-shaped component, and some model compounds containing electro- and photoactive units have been investigated. In an attempt to obtain the photoinduced abacus-like movement of the BPP34C10 macrocycle between the two stations, two strategies have been employed-one was based fully on processes that involved only the rotaxane components (intramolecular mechanism), while the other one required the help of external reactants (sacrificial mechanism). Both mechanisms imply a sequence of four steps (destabilization of the stable translational isomer, macrocyclic ring displacement, electronic reset, and nuclear reset) that have to compete with energy-wasteful steps. The results have demonstrated that photochemically driven switching can be performed successfully by the sacrificial mechanism, whereas, in the case of the intramolecular mechanism, it would appear that the electronic reset of the system is faster than the ring displacement.

19.
Eur J Cancer Prev ; 2(1): 17-23, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8428171

RESUMO

The authors have hypothesized that iodine-deficiency (I-def) or in some cases iodine-excess (I-excess) is associated with the development of gastric cancer. They report a short review of their own work and general literature on this subject in three fields: (1) epidemiology, where geographical and temporal correlations between territories with I-def (or I-excess) endemic goitre and high GC-death rate are reported; (2) immunology, where the possible correlations between I-def, immune-deficiency and GC are reported; and (3) thyroid gland and stomach correlations, both being embryologically derived from primitive gut and able to concentrate iodine. This ability is impaired by nitrates, thiocyanate, salt and by I-excess, which in fact can cause goitre. In our study I-def goitrous people have shown more atrophic gastritis than normal subjects. These data enable us to hypothesize that I-def or I-excess might constitute a new risk factor for gastric cancer, both by regulating gastric trophism and by antagonizing the action of those I-inhibitors (such as nitrates, thiocyanate and salt) previously studied as risk factors for gastric cancer.


Assuntos
Gastrite Atrófica/metabolismo , Bócio/metabolismo , Iodo/deficiência , Neoplasias Gástricas/etiologia , Feminino , Gastrite Atrófica/complicações , Bócio/complicações , Humanos , Imunoglobulina G/biossíntese , Imunoglobulina G/efeitos dos fármacos , Iodo/análise , Iodo/farmacologia , Masculino , Fatores de Risco , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/imunologia
20.
J Org Chem ; 65(7): 1947-56, 2000 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-10774013

RESUMO

The tetracationic cyclophane, cyclobis(paraquat-4,4'-biphenylene), binds 1,1'-disubstituted ferrocene-based polyethers as a result of (i) [pi...pi] stacking between the pi-electron-deficient bipyridinium units and the pi-electron-rich cyclopentadienyl rings and (ii) [C-H...O] hydrogen bonds between the alpha-bipyridinium hydrogen atoms and the polyether oxygen atoms. However, even the presence of a bulky tetraarylmethane group--which is too large to thread through the cavity of the cyclophane host--at the end of each of the two polyether substituents of the ferrocene-containing guest does not discourage adduct formation of the inclusion type. Thus, in these adducts, the ferrocene unit of the guest is located inside the cavity of the host with its two polyether chains protruding outward from the same side of the host. The alternative pseudorotaxane geometry is not observed in solutions of these 1:1 adducts. The host-guest adducts display absorption bands in the visible spectral region, characteristic of charge-transfer interactions. In the case of one of these adducts, reversible decomplexation/recomplexation takes place upon electrochemical oxidation/reduction of the ferrocene-based unit or upon reduction/oxidation of the tetracationic cyclophane.

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