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1.
Clin Radiol ; 72(8): 692.e9-692.e15, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28364952

RESUMO

AIM: To evaluate the incidence of adverse events and associated factors after radiofrequency ablation (RFA) in patients with hepatocellular carcinoma within 30 days. MATERIALS AND METHODS: The early complications that occurred within 30 days after RFA at a single institution from January 2000 to July 2010 were reviewed in order to evaluate the morbidity, mortality, and risk factors associated with the complications. In total, 1,211 patients (845 men, 70.5%) with a mean age of 68 years (range, 27-88 years) underwent 1,843 RFA procedures. RESULTS: The overall incidence rate of complications was 6.8% (125 cases). Major complications (n=36, 2%) included liver abscess (n=15, 0.8%), intraperitoneal bleeding (n=8, 0.4%), liver failure (n=5, 0.3%), variceal bleeding (n=3, 0.2%), haemothorax (n=2, 0.1%), cholecystitis (n=2, 0.1%), and bowel perforation (n=1, 0.1%). Among the minor complications (n=89, 4.8%), the most common was the post RFA syndrome accompanied by pain and fever (n=75, 4.1%). Other minor complications included significant pleural effusion (n=7, 0.4%), skin wound infection (n=4, 0.2%), and thermal injuries to the skin (n=3, 0.2%). Procedural infections significantly increased with tumour size (OR=1.379; 95% confidence interval [CI], 1.191-1.579; p<0.001), and multiple overlapping ablations (OR=1.118; 95% CI, 1.019-1.227, p=0.018). Thrombocytopenia (<50,000/µl), prothrombin time, and serum albumin level were significantly associated with post-RFA bleeding episodes (p=0.041, p=0.021, and p=0.003, respectively). The overall mortality rate was 0.3% (three cases of hepatic failure, two case of sepsis, and one case of renal failure). CONCLUSIONS: RFA is a safe and effective local treatment for hepatocellular carcinoma. Careful selection of patients and appropriate RFA planning could decrease procedural mortality and morbidity.


Assuntos
Carcinoma Hepatocelular/cirurgia , Ablação por Cateter/efeitos adversos , Neoplasias Hepáticas/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Adulto Jovem
2.
Clin Exp Rheumatol ; 33(2 Suppl 89): S-132-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26016764

RESUMO

OBJECTIVES: Because Takayasu arteritis (TA) predominantly affects females, few data regarding gender differences have been reported. The aim of the present study is to describe clinical features and angiographic findings of patients with TA according to gender. METHODS: According to the 1990 American College of Rheumatology criteria, 294 patients were diagnosed with TA between September 1994 and April 2014 at a single tertiary hospital. We reviewed clinical, laboratory, and radiologic data at the time of diagnosis. RESULTS: Among the 294 patients studied, 257 (87.4%) were female (male:female ratio=1:6.9). Female patients had a higher tendency to exhibit blood pressure differences between arms (p=0.595) and a weak pulse at the brachial artery (p=0.063). In male patients, we observed higher serum creatinine levels (p=0.038) and hypertension more frequently (p=0.061) than in females. Females exhibited more common lesions in the thoracic aorta and its branches, while males had more frequent lesions in the abdominal aorta and its branches. An analysis of angiographic classification according to the International TA Conference in Tokyo 1994 classification revealed that male patients had a higher incidence of type IV and females showed a higher incidence of types I, IIa, and IIb. CONCLUSIONS: Female patients with TA have more frequent involvement of the thoracic aorta and its branches, whereas involvement of the abdominal aorta and its branches is more common in males. Considering these gender-specific differences, adjustment of diagnostic criteria for TA according to gender may be necessary.


Assuntos
Aorta Torácica/diagnóstico por imagem , Artéria Carótida Primitiva/diagnóstico por imagem , Artéria Subclávia/diagnóstico por imagem , Arterite de Takayasu/diagnóstico por imagem , Adolescente , Adulto , Angiografia , Sedimentação Sanguínea , Proteína C-Reativa/metabolismo , Estudos de Coortes , Creatinina/sangue , Feminino , Hemoglobinas , Humanos , Hipertensão/etiologia , Claudicação Intermitente/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores Sexuais , Arterite de Takayasu/sangue , Arterite de Takayasu/complicações , Tomografia Computadorizada por Raios X , Adulto Jovem
3.
Phys Rev Lett ; 107(5): 057602, 2011 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-21867099

RESUMO

We report on nanoscale strain gradients in ferroelectric HoMnO(3) epitaxial thin films, resulting in a giant flexoelectric effect. Using grazing-incidence in-plane x-ray diffraction, we measured strain gradients in the films, which were 6 or 7 orders of magnitude larger than typical values reported for bulk oxides. The combination of transmission electron microscopy, electrical measurements, and electrostatic calculations showed that flexoelectricity provides a means of tuning the physical properties of ferroelectric epitaxial thin films, such as domain configurations and hysteresis curves.

4.
J Nutr Health Aging ; 25(5): 653-659, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33949633

RESUMO

OBJECTIVE: To explore the association of frailty and its eight components with claims-based healthcare costs among South Korean older adults aged 66 from 2009 to 2012. DESIGN: A cross-sectional design. SETTING: Data were obtained from administrative claims, Regular Biennial General and Cancer Screening Examinations, and the 66-year Lifetime Transitional Period Health Examination. PARTICIPANTS: South Korean older adults aged 66 (N = 818,337). MEASUREMENTS: Frailty was measured using eight components (i.e., hospital admission, self-assessed health status, polypharmacy, weight loss, depressed mood, incontinence, visual and auditory problems, and performance on the Timed Up and Go test). Healthcare costs included those associated with inpatient and outpatient care and pharmaceuticals. Multiple Tobit regression was used to assess the association between frailty and healthcare costs before and after propensity score matching. RESULTS: The mean annual total healthcare cost was $1,403.24 in robust participants, $2,364.78 in pre-frail participants, and $3,655.13 in frail participants. Among participants after propensity score matching, total healthcare costs were higher by $959.58 in the pre-frail (P < 0.001) and by $2,249.70 in the frail group (P < 0.001) compared to the robust group. The presence of each of the eight frailty components was significantly associated with higher total healthcare costs. CONCLUSION: By comparing the variables of interest using claims data, our study showed that frailty and each of its eight symptoms was associated with increased healthcare costs. This provides evidence of the need for identifying and managing frailty to reduce healthcare costs among South Korean older adults.


Assuntos
Fragilidade , Idoso , Estudos Transversais , Idoso Fragilizado , Custos de Cuidados de Saúde , Humanos , Equilíbrio Postural , República da Coreia , Estudos de Tempo e Movimento
5.
Genet Mol Res ; 9(2): 772-9, 2010 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-20449810

RESUMO

We examined the efficiency of direct sequencing of pooled DNA for developing common single nucleotide polymorphisms (SNPs) and its accuracy for estimating allele frequencies. A pool of 200 control DNAs was established and was used for developing SNPs and estimating minor allele frequencies (MAF). The sensitivity of the pooled DNA method for successfully detecting an SNP with an MAF >0.01 listed in the database was approximately 0.7; it was particularly efficient for detecting SNPs with MAF >0.1, which is compatible with the common disease/common variant hypothesis. The mean difference between the estimated and the observed MAFs was 0.03 +/- 0.023. The pooled DNA method identified four additional SNPs, for which the allele frequency information was not available in the database. The pooled DNA method is a cost- and time-effective tool for both qualifying and quantifying SNPs with considerable accuracy, and it can be particularly useful for dissecting the common disease/common variant hypothesis; this represents a best-case scenario for large-scale association mapping.


Assuntos
Frequência do Gene/genética , Modelos Genéticos , Polimorfismo de Nucleotídeo Único/genética , Análise de Sequência de DNA/métodos , Adulto , Humanos , Padrões de Referência , Adulto Jovem
6.
Clin Cardiol ; 42(3): 379-384, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30597592

RESUMO

BACKGROUND: A fragmented QRS complex (fQRS) is caused by conduction abnormalities of the ventricle secondary to myocardial ischemia and/or scar in patients with myocardial infarction. However, the implications of the fQRS in the development of coronary artery disease with myocardial ischemia in those without a scar remain unknown. METHODS: We studied electrocardiograms (ECGs) obtained from 150 patients (60.5 ± 8.5 years, 102 men) with myocardial ischemia, which was confirmed by performing both, a nuclear exercise stress test and coronary angiography. We also studied ECGs obtained from 601 patients (58.5 ± 10.0 years, 315 men) who showed a negative nuclear exercise stress test (control group). Patients in whom the nuclear exercise stress test showed a myocardial scar were excluded. RESULTS: An fQRS was more commonly observed in patients with myocardial ischemia (n = 48, 32.0%) than in the control group (n = 133, 22.1%) (P = 0.011). The sensitivity, specificity, positive, and negative predictive values of fQRS in diagnosing myocardial ischemia were 32.0, 77.9, 26.5, and 82.1%, respectively. The fQRS (odds ratio 1.580, 95% confidence interval 1.020-2.446, P = 0.040) was an independent predictor of myocardial ischemia after adjusting for age, sex, current smoking habits, ST-T changes on ECG, as well as histories of hypertension, diabetes, and dyslipidemia. Moreover, the fQRS showed an incremental prognostic value over conventional risk factors (χ2 = 5, P = 0.032) and over a combination of conventional factors and ST-T changes (χ2 = 9, P = 0.014). CONCLUSIONS: The fQRS is a moderately sensitive and independent predictor of myocardial ischemia.


Assuntos
Angiografia Coronária/métodos , Eletrocardiografia , Sistema de Condução Cardíaco/fisiopatologia , Isquemia Miocárdica/diagnóstico , Medição de Risco/métodos , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/fisiopatologia , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Risco
7.
Eye (Lond) ; 32(1): 136-141, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28799557

RESUMO

PurposeTo describe the use of an acellular dermal allograft (AlloDerm) for patients with insufficient conjunctiva during evisceration and implantation surgery.Patients and methodsThe medical records of six patients with insufficient conjunctiva during evisceration surgery were reviewed. It was not possible to close the Tenon's capsule and conjunctiva without wound tension in these patients, so AlloDerm was placed over the sclera, and the edges were sutured with adjacent conjunctiva without tension. The size of the bare AlloDerm graft was measured in all patients. The clinical outcome was the incidence of complications, and the percentage of patients needing additional surgery was also recorded.ResultsThe cause of evisceration was end stage glaucoma (four patients) and endogenous endophthalmitis (two patients). All six eyes of six patients (100%) had a successful outcome showing no complications. Four cases achieved full conjunctivalisation over the bare AlloDerm graft. Two cases had a bare AlloDerm until the last follow-up, but showed no implant exposure. It took a median of 11 weeks for the slow advance of the conjunctival edge to entirely cover the AlloDerm graft.ConclusionsAlloDerm is a promising material for covering sclera and implants in a tension-free manner after evisceration surgery in patients with insufficient conjunctiva.


Assuntos
Colágeno , Túnica Conjuntiva/cirurgia , Doenças da Túnica Conjuntiva/cirurgia , Evisceração do Olho/métodos , Implantes Orbitários , Procedimentos de Cirurgia Plástica/métodos , Idoso , Idoso de 80 Anos ou mais , Aloenxertos , Túnica Conjuntiva/patologia , Doenças da Túnica Conjuntiva/etiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
8.
Eye (Lond) ; 32(2): 439-445, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29052604

RESUMO

PurposeTo assess tear cytokine levels and clinical outcomes in meibomian gland dysfunction (MGD) in the blind eye of patients wearing an ocular prosthesis after 2 months of treatment with topical loteprednol etabonate and eyelid scrubs with warm compresses.Patients and methodsThis study included patients with MGD wearing a unilateral ocular prosthesis for more than 1 year. All patients topically received 0.5% loteprednol etabonate and were instructed to scrub their eyelids with warm compresses on the prosthetic eye for 2 months. We evaluated tear cytokine levels using Multiplex Bead Immunoassays, performed biomicroscopic examination of the lid margins and meibomian gland, conducted meibography imaging, and assessed MGD-related ocular symptoms using a questionnaire for the prosthetic eye before and 2 months after treatment.ResultsThirty consecutive patients were included. There were significant reductions in the levels of interleukin (IL)-6, interferon-γ, monocyte chemotactic protein-1, IL-8, tumor necrosis factor-α, and IL-1ß (P<0.001 for each cytokine). Moreover, there were improvements in ocular symptoms (P=0.001), lid margin abnormalities (P<0.001), meibomian gland expressibility (P<0.001) and meibography findings (P=0.037).ConclusionTopical loteprednol etabonate in conjunction with eyelid scrubs and warm compresses were effective in treating MGD in prosthetic eye wearers. Furthermore, tear cytokine measurements may serve as an additional approach for evaluating the efficacy of anti-inflammatory treatment for MGD in prosthetic eye wearers.


Assuntos
Antialérgicos/uso terapêutico , Olho Artificial/efeitos adversos , Doenças Palpebrais/tratamento farmacológico , Etabonato de Loteprednol/uso terapêutico , Glândulas Tarsais , Administração Tópica , Adulto , Idoso , Antialérgicos/administração & dosagem , Antialérgicos/farmacologia , Citocinas/metabolismo , Proteínas do Olho/metabolismo , Doenças Palpebrais/metabolismo , Doenças Palpebrais/patologia , Feminino , Humanos , Etabonato de Loteprednol/administração & dosagem , Etabonato de Loteprednol/farmacologia , Masculino , Glândulas Tarsais/efeitos dos fármacos , Glândulas Tarsais/metabolismo , Pessoa de Meia-Idade , Estudos Prospectivos , Lágrimas/metabolismo
9.
Biochim Biophys Acta ; 1463(2): 209-18, 2000 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-10675500

RESUMO

A 20-residue hybrid peptide (CA(1-8)-MA(1-12): KWKLFKKIGIGKFLHSAKKF-NH(2)) incorporating 1-8 residues of cecropin A (CA) and 1-12 residues of magainin 2 (MA) has potent antibiotic activity without hemolytic activity. In order to investigate the effects of the flexible hinge sequence, Gly-Ile-Gly of CA(1-8)-MA(1-12) (CA-MA) on antibiotic activity, CA-MA and its three analogues, CA-MA1, CA-MA2 and CA-MA3 were synthesized. The Gly-Ile-Gly sequence of CA-MA was deleted in CA-MA1 and replaced with Pro and Gly-Pro-Gly in CA-MA2 and CA-MA3, respectively. CA-MA1 and CA-MA3 caused a significant decrease in the bactericidal rate against Escherichia coli and Bacillus subtilis and the tumoricidal activity against four different tumor cells, and the PC/PS (4:1, w/w) vesicle-aggregating and disrupting activities. However, CA-MA2 showed a similar bactericidal rate and antitumor, vesicle-aggregating and disrupting activities, as compared with CA-MA. These results suggested that the flexibility or beta-turn induced by Gly-Ile-Gly or Pro in the central part of CA-MA may be important in the electrostatic interaction of the cationic short alpha-helical region in the N-terminus with the cell membrane surface and the hydrophobic interaction of amphipathic alpha-helical region in the C-terminus with the hydrophobic acyl chains in the cell membrane. CA-MA3 exhibited lower activity in antibacterial, antitumor, and vesicle-aggregating and disrupting activities than CA-MA and CA-MA2. This result suggested that the excessive beta-turn structure by Gly-Pro-Gly in CA-MA3 seems to interrupt the ion channel/pore formation on the lipid bilayer. It was concluded that the appropriate flexibility or beta-turn structure provided by the central hinge is responsible for the effective antibiotic activity of the antimicrobial peptides with the helix-hinge-helix structure.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos , Divisão Celular/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Lipossomos , Peptídeos/farmacologia , Células 3T3 , Sequência de Aminoácidos , Animais , Antibacterianos/química , Antibacterianos/toxicidade , Bacillus subtilis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Humanos , Células Jurkat , Camundongos , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/toxicidade , Pseudomonas aeruginosa/efeitos dos fármacos , Salmonella typhimurium/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Streptococcus pyogenes/efeitos dos fármacos , Relação Estrutura-Atividade , Células Tumorais Cultivadas
10.
Eye (Lond) ; 29(9): 1181-5, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26113504

RESUMO

PURPOSE: To compare the functional and cosmetic outcomes of two- and three-point sutures for advancing the levator aponeurosis in blepharoptosis surgery on Asians. PATIENTS AND METHODS: This retrospective study examined 60 Asian patients with blepharoptosis who had undergone advancement of the levator aponeurosis: 34 patients (46 eyelids) had ptosis correction using the two-point suture technique and 26 patients (41 eyelids) had ptosis correction using the three-point suture technique. The postoperative marginal reflex distance (MRD1), lid height difference, and eyelid contour were evaluated. RESULTS: Twenty-seven (79.4%) of the 34 patients in the two-point group and 19 (73.1%) of 26 patients in the three-point group had a postoperative MRD1 of 2-4 mm, lids within 0.5 mm of each other, and a satisfactory eyelid contour; this difference was not significant. The rate of reoperation did not differ significantly between the two groups. CONCLUSION: Two- and three-point sutures for advancing the levator aponeurosis were equally effective for correcting blepharoptosis in Asians.


Assuntos
Povo Asiático , Blefaroplastia/métodos , Blefaroptose/cirurgia , Músculos Oculomotores/cirurgia , Técnicas de Sutura , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pálpebras/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/cirurgia , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Adulto Jovem
11.
J Med Chem ; 42(16): 3055-65, 1999 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-10447949

RESUMO

Racemic 6-phenyl-4-phenylethynyl-1,4-dihydropyridine derivatives have been shown to be highly selective A(3) adenosine receptor antagonists (Jiang et al. J. Med. Chem. 1997, 40, 2596-2608). Methods for resolving the optical isomers at the C4 position, involving selective crystallization or chromatographic separation of diastereomeric ester derivatives, have been developed. Optically pure glycerol and threitol derivatives were used as chiral auxiliary groups for ester formation at the 3-position, resulting in diastereomeric mixtures of dihydropyridines. Esterification of a 6-phenyl-4-phenylethynyl-1,4-dihydropyridine derivative at the 3-position with a chiral, protected glycerol moiety, (S)-(+)-2, 2-dimethyl-1,3-dioxolane-4-methanol, allowed the selective crystallization of a pure diastereomer, 9. The (1)H NMR spectrum of 9 using the lanthanide shift reagent Eu(fod)(3) indicated optical purity, and the (4S,2'R)-configuration was assigned using X-ray crystallography. The noncrystalline (4R,2'R)-isomer 10 was also isolated and shown to be 3-fold more potent than the (4S,2'R)-isomer in binding to A(3) receptors. The 2,2-dimethyl-1,3-dioxolane moiety also served as a protected form of a diol, which showed selective reactivity versus a 5-ethyl ester in basic transesterification reactions. A racemic 5-carboxylic acid derivative could not be resolved through crystallization of diastereomeric salts. Enantiomers of 5-benzyl 3-ethyl 2-methyl-6-phenyl-4-phenylethynyl-1, 4-dihydropyridine-3,5-dicarboxylate (2) were obtained via an ester derived from (4R,5R)-(-)-2,3-O-isopropylidene-D-threitol at the 3-position, which was resolved using HPLC, and each diastereomer was subsequently deprotected in acidic conditions. The resulting diols were exchanged for ethyl ester groups by base-catalyzed transesterification. The binding of pure enantiomers of 2 at A(3) adenosine receptors indicated a 35-fold stereoselectivity for the (4S)-isomer 21. A receptor docking hypothesis, using a previously derived human A(3) receptor model, shows the bulkier of the two ester groups (5-Bn) of 21 oriented toward the exofacial side and the 4-position phenylethynyl group situated between transmembrane helical domain TM6 and TM7.


Assuntos
Di-Hidropiridinas/síntese química , Antagonistas de Receptores Purinérgicos P1 , Animais , Encéfalo/metabolismo , Linhagem Celular , Di-Hidropiridinas/química , Di-Hidropiridinas/metabolismo , Humanos , Técnicas In Vitro , Modelos Moleculares , Conformação Proteica , Ensaio Radioligante , Ratos , Receptor A3 de Adenosina , Receptores Purinérgicos P1/química , Receptores Purinérgicos P1/metabolismo , Estereoisomerismo , Relação Estrutura-Atividade
12.
J Med Chem ; 43(4): 746-55, 2000 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-10691699

RESUMO

P2Y(1) receptors are activated by ADP and occur on endothelial cells, smooth muscle, epithelial cells, lungs, pancreas, platelets, and in the central nervous system. With the aid of molecular modeling, we have designed nucleotide analogues that act as selective antagonists at this subtype. The present study has tested the hypothesis that acyclic modifications of the ribose ring, proven highly successful for nucleoside antiviral agents such as gancyclovir, are generalizable to P2Y receptor ligands. Specifically, the binding site of the P2Y(1) receptor was found to be sufficiently accommodating to allow the substitution of the ribose group with acyclic aliphatic and aromatic chains attached to the 9-position of adenine. Three groups of adenine derivatives having diverse side-chain structures, each containing two symmetrical phosphate or phosphonate groups, were prepared. Biological activity was demonstrated by the ability of the acyclic derivatives to act as agonists or antagonists in the stimulation of phospholipase C in turkey erythrocyte membranes. An acyclic N(6)-methyladenine derivative, 2-[2-(6-methylamino-purin-9-yl)-ethyl]-propane-1, 3-bisoxy(diammoniumphosphate) (10), containing an isopentyl bisphosphate moiety, was a full antagonist at the P2Y(1) receptor with an IC(50) value of 1.60 micro¿. The corresponding 2-Cl derivative (11) was even more potent with an IC(50) value of 0.84 microM. Homologation of the ethylene group at the 9-position to 3-5 methylene units or inclusion of cis- or trans-olefinic groups greatly reduced antagonist potency at the P2Y(1) receptor. Analogues containing a diethanolamine amide group and an aryl di(methylphosphonate) were both less potent than 10 as antagonists, with IC(50) values of 14 and 16 microM, respectively, and no agonist activity was observed for these analogues. Thus, the ribose moiety is clearly not essential for recognition by the turkey P2Y(1) receptor, although a cyclic structure appears to be important for receptor activation, and the acyclic approach to the design of P2 receptor antagonists is valid.


Assuntos
Adenina/análogos & derivados , Desoxiadenosinas/síntese química , Difosfonatos/síntese química , Organofosfatos/síntese química , Antagonistas do Receptor Purinérgico P2 , Adenina/síntese química , Adenina/química , Adenina/farmacologia , Desoxiadenosinas/química , Desoxiadenosinas/farmacologia , Difosfonatos/química , Difosfonatos/farmacologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Técnicas In Vitro , Fosfatos de Inositol/biossíntese , Organofosfatos/química , Organofosfatos/farmacologia , Agonistas do Receptor Purinérgico P2 , Receptores Purinérgicos P2Y1 , Relação Estrutura-Atividade , Turquia
13.
J Med Chem ; 43(5): 829-42, 2000 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-10715151

RESUMO

The structure-activity relationships of adenosine-3', 5'-bisphosphates as P2Y(1) receptor antagonists have been explored, revealing the potency-enhancing effects of the N(6)-methyl group and the ability to substitute the ribose moiety (Nandanan et al. J. Med. Chem. 1999, 42, 1625-1638). We have introduced constrained carbocyclic rings (to explore the role of sugar puckering), non-glycosyl bonds to the adenine moiety, and a phosphate group shift. The biological activity of each analogue at P2Y(1) receptors was characterized by measuring its capacity to stimulate phospholipase C in turkey erythrocyte membranes (agonist effect) and to inhibit its stimulation elicited by 30 nM 2-methylthioadenosine-5'-diphosphate (antagonist effect). Addition of the N(6)-methyl group in several cases converted pure agonists to antagonists. A carbocyclic N(6)-methyl-2'-deoxyadenosine bisphosphate analogue was a pure P2Y(1) receptor antagonist and equipotent to the ribose analogue (MRS 2179). In the series of ring-constrained methanocarba derivatives where a fused cyclopropane moiety constrained the pseudosugar ring of the nucleoside to either a Northern (N) or Southern (S) conformation, as defined in the pseudorotational cycle, the 6-NH(2) (N)-analogue was a pure agonist of EC(50) 155 nM and 86-fold more potent than the corresponding (S)-isomer. The 2-chloro-N(6)-methyl-(N)-methanocarba analogue was an antagonist of IC(50) 51.6 nM. Thus, the ribose ring (N)-conformation appeared to be favored in recognition at P2Y(1) receptors. A cyclobutyl analogue was an antagonist with IC(50) of 805 nM, while morpholine ring-containing analogues were nearly inactive. Anhydrohexitol ring-modified bisphosphate derivatives displayed micromolar potency as agonists (6-NH(2)) or antagonists (N(6)-methyl). A molecular model of the energy-minimized structures of the potent antagonists suggested that the two phosphate groups may occupy common regions. The (N)- and (S)-methanocarba agonist analogues were docked into the putative binding site of the previously reported P2Y(1) receptor model.


Assuntos
Nucleotídeos de Desoxiadenina/síntese química , Agonistas do Receptor Purinérgico P2 , Antagonistas do Receptor Purinérgico P2 , Ribose/química , Animais , Nucleotídeos de Desoxiadenina/química , Nucleotídeos de Desoxiadenina/farmacologia , Ativação Enzimática , Membrana Eritrocítica/enzimologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Técnicas In Vitro , Fosfatos de Inositol/metabolismo , Ligantes , Modelos Moleculares , Receptores Purinérgicos P2Y1 , Relação Estrutura-Atividade , Perus , Fosfolipases Tipo C/metabolismo
14.
J Med Chem ; 42(9): 1625-38, 1999 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-10229631

RESUMO

The P2Y1 receptor is present in the heart, in skeletal and various smooth muscles, and in platelets, where its activation is linked to aggregation. Adenosine 3',5'- and 2',5'-bisphosphates have been identified as selective antagonists at the P2Y1 receptor (Boyer et al. Mol. Pharmacol. 1996, 50, 1323-1329) and have been modified structurally to increase receptor affinity (Camaioni et al. J. Med. Chem. 1998, 41, 183-190). We have extended the structure-activity relationships to a new series of deoxyadenosine bisphosphates with substitutions in the adenine base, ribose moiety, and phosphate groups. The activity of each analogue at P2Y1 receptors was determined by measuring its capacity to stimulate phospholipase C in turkey erythrocyte membranes (agonist effect) and to inhibit phospholipase C stimulation elicited by 10 nM 2-(methylthio)adenosine 5'-diphosphate (antagonist effect). 2'-Deoxyadenosine bisphosphate analogues containing halo, amino, and thioether groups at the 2-position of the adenine ring were more potent P2Y1 receptor antagonists than analogues containing various heteroatom substitutions at the 8-position. An N6-methyl-2-chloro analogue, 6, was a full antagonist and displayed an IC50 of 206 nM. Similarly, N6-methyl-2-alkylthio derivatives 10, 14, and 15 were nearly full antagonists of IC50 < 0.5 microM. On the ribose moiety, 2'-hydroxy, 4'-thio, carbocyclic, and six-membered anhydrohexitol ring modifications have been prepared and resulted in enhanced agonist properties. The 1,5-anhydrohexitol analogue 36 was a pure agonist with an EC50 of 3 microM, i.e., similar in potency to ATP. 5'-Phosphate groups have been modified in the form of triphosphate, methyl phosphate, and cyclic 3',5'-diphosphate derivatives. The carbocyclic analogue had enhanced agonist efficacy, and the 5'-O-phosphonylmethyl modification was tolerated, suggesting that deviations from the nucleotide structure may result in improved utility as pharmacological probes. The N6-methoxy modification eliminated receptor affinity. Pyrimidine nucleoside 3', 5'-bisphosphate derivatives were inactive as agonists or antagonists at P2Y receptor subtypes.


Assuntos
Desoxiadenosinas/síntese química , Organofosfatos/síntese química , Agonistas do Receptor Purinérgico P2 , Antagonistas do Receptor Purinérgico P2 , Animais , Linhagem Celular , Desoxiadenosinas/química , Desoxiadenosinas/farmacologia , Ativação Enzimática , Membrana Eritrocítica/efeitos dos fármacos , Membrana Eritrocítica/enzimologia , Membrana Eritrocítica/metabolismo , Humanos , Técnicas In Vitro , Organofosfatos/química , Organofosfatos/farmacologia , Receptores Purinérgicos P2/biossíntese , Receptores Purinérgicos P2Y1 , Relação Estrutura-Atividade , Perus , Fosfolipases Tipo C/metabolismo
15.
Behav Brain Res ; 121(1-2): 137-47, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11275291

RESUMO

It is well known that repeated injections of nicotine produce progressively larger increases in locomotor activity, an effect referred to as behavioral sensitization. This study was carried out to investigate the neural mechanisms underlying nicotine-induced behavioral sensitization using in vivo microdialysis and Fos-like immunohistochemistry (FLI). Rats were given repeated injections of saline or nicotine (0.4 mg/kg s.c., twice daily for 7 days) followed by one challenge injection on the 4th day after the last daily injection. Systemic challenge with nicotine produced a much larger increase in locomotor activity in nicotine-pretreated rats (659.1+/-94.9 counts/2 h) than in saline-pretreated rats (218.1+/-61 counts/2 h). A direct local challenge of nicotine (1 or 5 mM) via a microdialysis probe in the nucleus accumbens or striatum induced a much greater dose-dependent increase of dopamine (DA) output in nicotine-pretreated rats than in saline-pretreated rats. Furthermore, in parallel with the behavioral and biochemical data, systemic challenge with nicotine produced marked Fos-like immunohistochemistry in the nucleus accumbens and the striatum in the nicotine-pretreated rats. Taken together, this study demonstrates that behavioral sensitization is clearly associated with an increase in DA release and activation of Fos-like immunoreactive cells in the striatum and the nucleus accumbens produced by repeated nicotine treatment. Our results strongly suggest that the striatum and the nucleus accumbens may play a major role in nicotine-induced behavioral sensitization. The present results are discussed in terms of the development and expression of nicotine-induced behavioral sensitization.


Assuntos
Nível de Alerta/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Dopamina/metabolismo , Atividade Motora/efeitos dos fármacos , Nicotina/farmacologia , Núcleo Accumbens/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-fos/metabolismo , Animais , Relação Dose-Resposta a Droga , Injeções Subcutâneas , Microdiálise , Ratos
16.
Comp Biochem Physiol B Biochem Mol Biol ; 126(4): 543-52, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11026666

RESUMO

The identity of the neutral cholesteryl ester hydrolase (CEH) in human monocyte/macrophages is uncertain. Prior studies indicate that hormone sensitive lipase (HSL) is a major CEH in mouse macrophages, and that HSL mRNA is present in human THP-1 monocytes. In the present study, HSL mRNA expression was examined in THP-1 cells as a function of differentiation status and cholesterol enrichment. By RT-PCR with primer pairs that span exon boundaries, HSL mRNA was demonstrated in THP-1 monocytes and phorbol-ester differentiated THP-1 macrophages. cDNA identities were confirmed by sequencing. By Northern blotting, with HSL cDNA as probe, THP-1 monocytes were found to contain HSL mRNA of approximately 3 and 3.9 kb. In THP-1 macrophages, the 3 kb mRNA was greatly diminished, while the level of the 3.9 kb mRNA was maintained. mRNA of approximately 3 and 3.9 kb are those expected of the 86-kDa (adipocyte) and 117-kDa (testicular) HSL isoforms, respectively. The presence of the testicular isoform mRNA was confirmed in THP-1 cells by amplification and sequencing of an isoform-specific cDNA. Additionally, Northern-blot comparisons showed that the 3 and 3.9 kb mRNA in THP-1 comigrated with the HSL mRNA in 3T3-L1 adipocytes and rat testis, respectively. The level of the 3.9 kb mRNA did not vary greatly with cholesterol enrichment. Thus, the HSL gene is transcribed in THP-1 cells both before and after differentiation into macrophages; after differentiation, the predominant mRNA is that for the 117-kDa isoform. This isoform is a CEH, and may mediate some CE turnover in THP-1 cells.


Assuntos
Macrófagos/metabolismo , Monócitos/metabolismo , RNA Mensageiro/metabolismo , Esterol Esterase/genética , Northern Blotting , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Macrófagos/enzimologia , Masculino , Monócitos/enzimologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esterol Esterase/metabolismo , Testículo/enzimologia , Testículo/metabolismo , Células Tumorais Cultivadas
17.
Eye (Lond) ; 28(10): 1212-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25081289

RESUMO

PURPOSE: Long-standing prosthetic eye wearing induces ocular surface inflammation. We investigated the short-term effects of topical cyclosporine A 0.05% (Restasis) in patients with ocular discomfort resulting from long-standing prosthetic eye wearing. METHODS: This was a prospective, interventional case series. Patients who were unilateral prosthetic eye wearers over a period of 5 years were enrolled at a single institution from March to July 2013. The subjects were instructed to instill topical cyclosporine A 0.05% twice per day. Measurements were made pre-treatment and after 1 and 3 months of treatment. Outcome measures were the ocular symptom score, the lid margin abnormality score, the Schirmer test, and the tear meniscus amount, using Fourier-domain optical coherence tomography. RESULTS: In total, 20 consecutive patients (mean age: 60.1 years, 8 males, 12 females) were included. Ocular symptoms were improved after treatment for 1 month in all patients (ocular symptom score pre-treatment 76.83 vs 46.75 after treatment; P<0.001). There was no statistically significant difference in lid margin abnormality score or tear meniscus amount. The Schirmer test results were improved after treatment for 3 months (pre- and after treatment, 6.70 vs 11.40; P<0.001). CONCLUSIONS: Topical cyclosporine A 0.05% showed a satisfactory effect in long-standing prosthetic eye wearers. Ocular symptoms were markedly relieved in all subjects after treatment for 1 month.


Assuntos
Ciclosporina/administração & dosagem , Síndromes do Olho Seco/tratamento farmacológico , Olho Artificial/efeitos adversos , Imunossupressores/administração & dosagem , Administração Tópica , Adulto , Idoso , Idoso de 80 Anos ou mais , Síndromes do Olho Seco/etiologia , Síndromes do Olho Seco/fisiopatologia , Pálpebras/efeitos dos fármacos , Pálpebras/patologia , Feminino , Análise de Fourier , Humanos , Masculino , Pessoa de Meia-Idade , Soluções Oftálmicas , Projetos Piloto , Estudos Prospectivos , Lágrimas/fisiologia , Fatores de Tempo , Tomografia de Coerência Óptica
18.
Eye (Lond) ; 27(8): 964-71, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23743527

RESUMO

AIMS: To investigate if TSH-receptor antibody (TRAb) levels measured in early Graves' orbitopathy (GO) stages are predictive of clinical disease course beyond 1 year after initial GO diagnosis and to compare performance of two newly developed TRAb assays (third-generation thyrotropin-binding inhibitor immunoglobulin (TBII) assay vs Mc4-thyroid-stimulating immunoglobulin (TSI) bioassay) in predicting disease course. METHODS: Newly diagnosed, untreated GO patients whose duration of ocular symptoms was less than 6 months were included. One year after initial diagnosis, all patients were classified as presenting either a mild (Group 1) or severe course (Group 2) according to their clinical manifestations. The measurements of two TRAb assays at initial GO diagnosis were used for analysis. RESULTS: Data from 112 patients were available for analysis. Seventy-three patients (65.2%) were designated as Group 1, and 39 patients (34.8%) as Group 2. Patients with higher initial TRAb levels demonstrated a higher risk of severe disease course upon multiple regression analysis (P<0.01). The cutoff values for the prediction of severe course of the third-generation TBII and Mc4-TSI assays were 10.67 IU/l and 555.10%, respectively, with assay specificities of 84.9 and 89.0%. The TBII assay predictive power (area under the curve (AUC)=0.817; 95% confidence interval (CI) =0.732-0.902) was equivalent to the TSI bioassay (AUC=0.868, 95% CI=0.803-0.934) (P=0.203). CONCLUSIONS: The predictive power of the third-generation TBII assay and Mc4-TSI bioassay are similarly strong. Measurement of TRAb using either third-generation TBII or Mc4-TSI in early GO periods would provide important prognostic information on future GO course.


Assuntos
Autoanticorpos/sangue , Bioensaio/métodos , Oftalmopatia de Graves/imunologia , Imunoensaio/métodos , Receptores da Tireotropina/imunologia , Adulto , Feminino , Oftalmopatia de Graves/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Receptores da Tireotropina/sangue , Análise de Regressão , Estudos Retrospectivos
19.
Neuroscience ; 238: 258-69, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23485808

RESUMO

Although mitochondrial dysfunction is intimately related to axonal degeneration following nerve injury, the molecular mechanisms of mitochondrial swelling and its mechanistic relation to axonal degeneration are largely unknown. Previous studies have demonstrated that axonal degeneration in the injured peripheral nerves shows two morphologically distinct phases: (1) A latency period (∼24h), in which the morphology of axonal cytoskeletons seems unchanged, followed by (2) an execution period (36-48h), which shows a catastrophic granular degeneration of most axonal structures in rodent axons. In the present study, we found that, in the sciatic nerve axotomy model, energy failure and microtubule depolymerization occurred during the latency period whereas mitochondrial swelling and neurofilament degradation started in the execution period. The energy repletion with NAD or an NAD/pyruvate mixture inhibited microtubule depolymerization, mitochondrial swelling and axonal degeneration in transected sciatic nerve axons. In addition, microtubule perturbing agents enhanced axonal degeneration and mitochondrial swelling. Extracellular calcium chelation did not affect energy failure, microtubule depolymerization or mitochondrial swelling, but it did prevent neurofilament degradation. These findings suggest that an early disturbance in energy dynamics regardless of mitochondrial swelling might be a key trigger for the initiation of axonal degeneration and that extracellular calcium influx is a late effector for neurofilament degradation.


Assuntos
Axônios/metabolismo , Microtúbulos/metabolismo , Dilatação Mitocondrial/fisiologia , Nervo Isquiático/lesões , Degeneração Walleriana/metabolismo , Animais , Axônios/efeitos dos fármacos , Axônios/patologia , Axotomia , Camundongos , Camundongos Endogâmicos C57BL , Microtúbulos/efeitos dos fármacos , Microtúbulos/patologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Dilatação Mitocondrial/efeitos dos fármacos , Paclitaxel/farmacologia , Nervo Isquiático/metabolismo , Nervo Isquiático/patologia , Moduladores de Tubulina/farmacologia , Vincristina/farmacologia , Degeneração Walleriana/patologia
20.
Eye (Lond) ; 26(9): 1263-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22744391

RESUMO

AIM: To compare clinical characteristics and thyroid-stimulating hormone receptor antibodies (TRAbs) in thyroid-associated ophthalmopathy (TAO) in euthyroid Korean patients with those in hyperthyroid patients. METHODS: Clinical activity scores (CASs), modified NOSPECS scores, exophthalmometry values, prevalence of optic neuropathy, restrictive myopathy and lid retraction, and the positivity and levels of TRAb (thyrotropin-binding inhibitor immunoglobulin (TBII) and thyroid-stimulating immunoglobulin (TSI)) were compared in 24 euthyroid (group A) and 139 clinical/subclinical hyperthyroid TAO patients (group B). RESULTS: Group A presented more clinically unilateral involvement than group B (79.2% vs 27.3%, P<0.001), less active (CAS 1.50 vs 2.26, P=0.014) and less severe clinical course (NOSPECS 3.38 vs 4.13, P=0.037). Lid retraction was more prevalent in group A than group B (91.7% vs 66.2%, P=0.014). Prevalence of optic neuropathy and restrictive myopathy, and the mean value of exophthalmometry were not different. Mean TBII levels were lower (7.20 IU/l) in group A than in group B (44.58 IU/l, P<0.001). A similar difference was found in the TSI bioassay (201.40% vs 425.19%, P=0.001). The positive rate of TBII in group A (34.8%) was significantly lower than in group B (90.8%, P<0.001). The positive rate of TSI was high in both group A (83.3%) and B (91.7%), with no significant difference (P=0.337). CONCLUSIONS: Patients with euthyroid TAO showed a less active and severe clinical course, more unilateral involvement, and lower levels of TRAb than those in patients with hyperthyroid TAO. These distinct clinical and biochemical characteristics might be useful in assessment of euthyroid TAO, and the TSI might be more sensitive for diagnosing these patients.


Assuntos
Síndromes do Eutireóideo Doente/diagnóstico , Oftalmopatia de Graves/diagnóstico , Adulto , Síndromes do Eutireóideo Doente/imunologia , Doenças Palpebrais/diagnóstico , Doenças Palpebrais/imunologia , Feminino , Oftalmopatia de Graves/imunologia , Humanos , Hipertireoidismo/diagnóstico , Hipertireoidismo/imunologia , Imunoglobulinas Estimuladoras da Glândula Tireoide/sangue , Coreia (Geográfico) , Masculino , Doenças do Nervo Óptico/diagnóstico , Doenças do Nervo Óptico/imunologia , Receptores da Tireotropina/imunologia , Estudos Retrospectivos , Tiroxina/sangue , Tomografia Computadorizada por Raios X , Tri-Iodotironina/sangue , Acuidade Visual
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