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1.
ChemSusChem ; 16(17): e202202297, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37424157

RESUMO

Solid-state zinc ion batteries (ZIBs) and aluminum-ion batteries (AIBs) are deemed as promising candidates for supplying power in wearable devices due to merits of low cost, high safety, and tunable flexibility. However, their wide-scale practical application is limited by various challenges, down to the material level. This Review begins with elaboration of the root causes and their detrimental effect for four main limitations: electrode-electrolyte interface contact, electrolyte ionic conductivity, mechanical strength, and electrochemical stability window of the electrolyte. Thereafter, various strategies to mitigate each of the described limitation are discussed along with future research direction perspectives. Finally, to estimate the viability of these technologies for wearable applications, economic-performance metrics are compared against Li-ion batteries.

2.
Small ; 19(29): e2207133, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36971296

RESUMO

Rechargeable aqueous Zn/S batteries exhibit high capacity and energy density. However, the long-term battery performance is bottlenecked by the sulfur side reactions and serious Zn anode dendritic growth in the aqueous electrolyte medium. This work addresses the problem of sulfur side reactions and zinc dendrite growth simultaneously by developing a unique hybrid aqueous electrolyte using ethylene glycol as a co-solvent. The designed hybrid electrolyte enables the fabricated Zn/S battery to deliver an unprecedented capacity of 1435 mAh g-1 and an excellent energy density of 730 Wh kg-1 at 0.1 Ag-1 . In addition, the battery exhibits capacity retention of 70% after 250 cycles even at 3 Ag-1 . Moreover, the cathode charge-discharge mechanism studies demonstrate a multi-step conversion reaction. During discharge, the elemental sulfur is sequentially reduced by Zn to S2- ( S 8 → S x 2 - → S 2 2 - + S 2 - ) ${{\rm{S}}_8}{\bm{ \to }}{\rm{S}}_{\rm{x}}^{2{\bm{ - }}}{\bm{ \to }}{\rm{S}}_2^{2{\bm{ - }}}{\bm{ + }}{{\rm{S}}^{2{\bm{ - }}}})$ , forming ZnS. On charging, the ZnS and short-chain polysulfides will oxidize back to elemental sulfur. This electrolyte design strategy and unique multi-step electrochemistry of the Zn/S system provide a new pathway in tackling both key issues of Zn dendritic growth and sulfur side reactions, and also in designing better Zn/S batteries in the future.

3.
Med J Malaysia ; 76(2): 190-198, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33742627

RESUMO

INTRODUCTION: The aim of this study was to compare the visual outcomes of phacoemulsification with intraocular lens implantation (IOL) surgery in patients with and without diabetes mellitus (DM) in Malaysia over a 12-year period and to identify factors that may contribute to poor visual outcome. MATERIALS AND METHODS: Data was retrieved from the webbased Malaysian Cataract Surgery Registry (CSR). Perioperative data for cataract surgery performed from 2007- 2018 were analysed. Inclusion criteria were age ≥40 years, phacoemulsification and IOL and senile cataract. Combined surgeries, surgeries performed by trainees and ocular comorbidities were excluded. Post-operative Best-Corrected Visual Acuity (BCVA) were compared. Factors affecting poor visual outcomes among those with DM were analysed using multivariate logistic regression to produce adjusted odds ratio (OR) for variables of interest. RESULTS: Total number of cases between 2007-2018 was 442,858, of whom 179,210 qualified for our analysis. DM group consisted of 72,087 cases (40.2%). There were 94.5% cases in DM group and 95.0Z from non-DM group who achieved BCVA ≥6/12 (p<0.001). Among patients with DM, advanced age (70-79 years old, OR: 2.54, 95% Confidence Interva, 95%CI: 1.91, 3.40; 80-89 years old, OR: 5.50, 95%CI: 4.02, 7.51), ≥90 years, OR: 9.77, 95%CI: 4.18, 22.81), poor preoperative presenting visual acuity [<6/18-6/60] (OR: 2.40, 95%CI: 1.84, 3.14) and <6/60-3/60 (OR: 3.00, 95%CI: 2.24, 4.02), <3/60 (OR 3.63, 95%CI: 2.77, 4.74)], presence of intraoperative complication (OR 2.24, 95%CI: 1.86, 2.71) and presence of postoperative complication (OR 5.21, 95%CI: 2.97, 9.16) were significant factors for poor visual outcome. CONCLUSIONS: Visual outcomes following phacoemulsification with IOL implantation surgery among cases with DM were poorer compared to cases without DM. Risk factors for poor visual outcomes among cases with DM were identified.


Assuntos
Diabetes Mellitus , Lentes Intraoculares , Facoemulsificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Implante de Lente Intraocular , Resultado do Tratamento , Acuidade Visual
4.
Climacteric ; 20(6): 564-570, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28866964

RESUMO

OBJECTIVE: To assess the effects of isoflavones and 17ß-estradiol on the vaginal epithelium extracellular matrix and hyaluronic acid (HA) in the diabetic rat model. METHODS: Sixty adult, virgin, female rats underwent ovariectomy, then randomization into six groups of ten animals each: GI, sham ovariectomized control animals; GII, sham ovariectomized control diabetic animals; GIII, control ovariectomized rats receiving propylene glycol vehicle; GIV, control ovariectomized diabetic animals receiving propylene glycol vehicle; GV, diabetic ovariectomized animals treated with soy isoflavones (150 mg/kg by gavage); GVI, ovariectomized diabetic rats treated with estrogen (17ß-estradiol, 10 mg/kg, subcutaneously). Treatment took place over 30 consecutive days. After euthanasia, a portion of the vagina was immersed in liquid nitrogen for RT-qPCR and Western blotting. Another portion was processed for paraffin embedding. Sections were stained with hematoxylin & eosin for histomorphometry and Picro Sirius Red for collagen quantification. RESULTS: Vaginal epithelium histomorphometry in GIII (15.3 ± 1.1 µm) and GIV (14.5 ± 1.8 µm) was thinner than in GV (41.3 ± 1.5 µm) and GVI (74.3 ± 1.6 µm). There was an increase in collagen content in GV (84.1 ± 1.2 µm) and GVI (88.2 ± 1.7 µm). HA quantification was higher in GV (0.38 ± 1.1 µg/mg) and GVI (0.49 ± 1.4 µg/mg) when compared with GIII (0.12 ± 1.1 µg/mg) and GIV (0.10 ± 1.2 µg/mg), p < 0.05. CONCLUSIONS: Soy isoflavones increase hyaluronic acid concentration in the vagina of diabetic ovariectomized rats. Such findings might help to attenuate the effects of vulvovaginal atrophy in women.


Assuntos
Diabetes Mellitus Experimental , Glycine max , Ácido Hialurônico/metabolismo , Isoflavonas/farmacologia , Vagina/efeitos dos fármacos , Animais , Atrofia/prevenção & controle , Modelos Animais de Doenças , Feminino , Ovariectomia , Distribuição Aleatória , Ratos , Vagina/metabolismo , Vagina/patologia
6.
J Mol Biol ; 405(3): 736-53, 2011 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-21094167

RESUMO

Eukaryotic initiation factor (eIF)4E is overexpressed in many types of cancer such as breast, head and neck, and lung. A consequence of increased levels of eIF4E is the preferential translation of pro-tumorigenic proteins such as c-Myc, cyclin D1, and vascular endothelial growth factor. Inhibition of eIF4E is therefore a potential therapeutic target for human cancers. A novel peptide based on the eIF4E-binding peptide eIF4G1, where the α-helix was stabilized by the inclusion of α-helix inducers as shown by CD measurements, was synthesized. The helically stabilized peptide binds with an apparent K(d) of 9.43±2.57 nM, which is ∼15.7-fold more potent than the template peptide from which it is designed. The helically stabilized peptide showed significant biological activity at a concentration of 400 µM, unlike the naturally occurring eIFG1 peptide when measured in cell-based cap-dependent translational reporter and WST-1 (4-[3-(4-iodophenyl)-2-(4-nitrophenyl)-2H-5-tetrazolio]-1,3-benzene disulfonate) assays. Fusion of the template peptide and the stabilized peptide to the cell-penetrating peptide TAT produced more active but equally potent inhibitors of cap-dependent translation in cell lines. They also equally disrupted cell metabolism as measured in a WST-1 assay. Propidium iodide staining revealed that the TAT-fused, helically stabilized peptide caused more cell death than the TAT-fused eIF4G1 template peptide with substantial decreases in the G1 and G2 cell populations. Annexin-staining experiments also indicated that the TAT-fused eIF4G1 derivative peptides caused cell death by apoptosis. The results presented should offer further insight into peptidomimetics development for eIF4E.


Assuntos
Antineoplásicos/química , Desenho de Fármacos , Fator de Iniciação 4E em Eucariotos/química , Fator de Iniciação Eucariótico 4G/química , Peptidomiméticos/química , Proteínas Recombinantes de Fusão/química , Sequência de Aminoácidos , Antineoplásicos/metabolismo , Apoptose , Linhagem Celular Tumoral , Fator de Iniciação 4E em Eucariotos/genética , Fator de Iniciação Eucariótico 4G/genética , Produtos do Gene tat/química , Produtos do Gene tat/genética , Produtos do Gene tat/metabolismo , Humanos , Dados de Sequência Molecular , Peptidomiméticos/metabolismo , Ligação Proteica , Biossíntese de Proteínas/efeitos dos fármacos , Estrutura Secundária de Proteína , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
7.
Singapore Med J ; 51(7): 551-7, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20730394

RESUMO

INTRODUCTION: The effects of tinnitus on quality of life (QOL) have never been extensively studied in Singapore. We describe the characteristics of tinnitus and its impact on QOL as measured by the Tinnitus Handicap Inventory (THI) in a series of ear, nose and throat clinic patients. METHODS: A total of 327 patients who attended a tinnitus counselling clinic completed the THI questionnaire, a self-report measure with 25 items grouped into functional, emotional and catastrophic subscales. RESULTS: The mean age of the 134 female and 193 male patients was 48.9 years. 36.7 percent of these patients had bilateral tinnitus and 64.6 percent had symptoms for less than one year. 270 patients had hearing loss, 74 percent of whom presented with bilateral high frequency hearing loss. Most patients (84.1 percent) perceived only one type of sound. The total THI score distribution was: 107 (33 percent) patients had THI less than 16, 100 (31 percent) had THI 18 to 36, 59 (18 percent) had THI 38 to 56, and 61 (19 percent) had THI more than 58. There were no differences in the overall THI and subscale scores between the patients' gender, those with or without hearing loss, and those with unilateral or bilateral tinnitus. However, significantly higher total THI and all subscale scores were found among patients who were hearing more than one type of tinnitus sound. The areas of concern that were commonly reported by the patients in this series were a lack of control over tinnitus, frustration and stress. CONCLUSION: Tinnitus patients who hear multiple sounds tend to have a higher THI and subscale scores. The management of tinnitus should address common areas of concern, and may include counselling. The THI is a potential screening tool to determine if patients require counselling. A series of THI assessments can be used to chart the progress of treatment.


Assuntos
Avaliação da Deficiência , Qualidade de Vida , Zumbido/epidemiologia , Zumbido/psicologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Distribuição por Sexo , Singapura/epidemiologia , Estresse Psicológico , Inquéritos e Questionários , Zumbido/diagnóstico , Adulto Jovem
8.
Cell Prolif ; 43(4): 405-17, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20590666

RESUMO

OBJECTIVES: The aim of the present study was to improve efficiency of isolation and to optimize proliferative potential of human spermatogonial stem cells (SSCs) obtained from obstructive azoospermic (OA) and non-obstructive azoospermic (NOA) patients, and further, to characterize these cells for potential use in infertility treatment or study of reproductive biology. MATERIALS AND METHODS: We have applied a cell-sorting method, using collagen and magnetic activated cell separation to overcome obstacles, developing a collection system, and simple long-term proliferation system, that yields large numbers of high-purity SSCs from obstructive OA and NOA patients. RESULTS: SSCs derived from OA and NOA patients proliferated and maintained their characteristics for more than 12 passages (>6 months) in vitro. Moreover, the population of cells positive for the SSC-specific markers GFRalpha-1 and integrin alpha6, increased to more than 80% at passage 8. CONCLUSION: These finding may support the idea that in vitro propagation of SSCs could be a useful tool for infertility treatment and study of reproductive biology.


Assuntos
Espermatogônias/citologia , Células-Tronco/citologia , Azoospermia , Separação Celular , Humanos , Masculino , Pesquisa
9.
Artigo em Inglês | MEDLINE | ID: mdl-11312467

RESUMO

We report the first case of foreign-body granuloma occurring in the mandible of a patient with a history of orthognathic surgery. A 20-year-old male patient had a hard swelling and pain in the left mandibular angle and the parotid area. Plain radiographs showed a radiolucent lesion extending from the buccal area under the left sigmoid notch of the mandible to the mandibular angle. Computed tomographs showed an expanded osteolytic mass in the same area, with destruction of most of the bone on the buccal side. A microscopic examination revealed filamentous foreign material associated with chronic inflammatory cell infiltration and an aggregation of multinucleated giant cells. Foreign-body granuloma in the mandible, although rare, should be included in the differential diagnosis in cases of postoperative masses.


Assuntos
Granuloma de Corpo Estranho/diagnóstico por imagem , Doenças Mandibulares/diagnóstico por imagem , Procedimentos Cirúrgicos Bucais/efeitos adversos , Adulto , Gossypium , Granuloma de Corpo Estranho/etiologia , Humanos , Masculino , Doenças Mandibulares/etiologia , Radiografia
10.
AAOHN J ; 48(10): 487-97; quiz 498-9, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11760259

RESUMO

Recent studies have indicated implementation of the CISM Program has impacted and reduced the cost of workers' compensation claims for stress related conditions and the number of lost work days (Ott, 1997; Western Management Consultants, 1996). Occupational health professionals need to be ready to develop and implement a comprehensive critical incident stress management process in anticipation of a major event. The ability to organize, lead, or administer critical incident stress debriefings for affected employees is a key role for the occupational health professional. Familiarity with these concepts and the ability to identify a critical incident enhances value to the business by mitigating the stress and impact to the workplace. Critical Incident Stress Management Systems have the potential for decreasing stress and restoring employees to normal life function--a win/win situation for both the employees and the organization.


Assuntos
Intervenção em Crise/organização & administração , Enfermagem do Trabalho/organização & administração , Serviços de Saúde do Trabalhador/organização & administração , Transtornos de Estresse Pós-Traumáticos/prevenção & controle , Transtornos de Estresse Pós-Traumáticos/psicologia , Local de Trabalho/psicologia , Absenteísmo , Adaptação Psicológica , Humanos , Descrição de Cargo , Acontecimentos que Mudam a Vida , Modelos Psicológicos , Desenvolvimento de Programas , Psicoterapia de Grupo/organização & administração , Transtornos de Estresse Pós-Traumáticos/etiologia
11.
Am J Otolaryngol ; 20(6): 383-90, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10609483

RESUMO

PURPOSE: To further clarify the clinical significance of neck node metastasis in squamous cell carcinoma of the maxillary sinus (maxillary SCC). MATERIALS AND METHODS: The medical charts of the 116 patients with maxillary SCC were retrospectively reviewed. Twelve patients (10.3%) presented initially with neck node metastases, and 14 (13.5%) of 104 node-negative patients subsequently developed regional recurrence during the follow-up period. The high-risk factors for neck node metastasis, patterns of regional failure, and survival for node-positive patients were analyzed with the patient cohort that had largely been treated with radiation alone. RESULTS: Of the various factors, the tumor extension to the nasopharynx or oral cavity was the statistically significant determinants predictive of neck node metastasis at the initial diagnosis. During the follow-up period, regional failure was far less common than local failure (19.0% v 68.1%), and the majority of regional failures were accompanied by local recurrences. The oral cavity extension and control status of local disease were the high-risk factors for subsequent development of regional recurrence in node-negative patients. The overall 5-year survival rate for node-positive patients (16.7%) showed a poorer outcome compared with that for node-negative patients (31.3%), but it was similar to that of T4N0 patients (26.6%). Although patients who subsequently developed neck node recurrence during follow-up represented a dismal prognosis, uncontrolled local diseases in these patients still remained a major problem, resulting in a poor prognosis. CONCLUSIONS: Despite an unfavorable prognosis of patients with neck node metastasis, an aggressive trial to achieve maximum local control of the primary tumor was considered to be more important than elective neck treatments.


Assuntos
Carcinoma de Células Escamosas/secundário , Neoplasias de Cabeça e Pescoço/secundário , Neoplasias do Seio Maxilar/patologia , Adulto , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirurgia , Terapia Combinada , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Metástase Linfática , Masculino , Neoplasias do Seio Maxilar/radioterapia , Neoplasias do Seio Maxilar/cirurgia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Segunda Neoplasia Primária , Prognóstico , Estudos Retrospectivos
12.
Dentomaxillofac Radiol ; 28(6): 386-90, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10578197

RESUMO

Pigmented villonodular synovitis (PVNS) is a rare lesion of the temporomandibular joint. We report a case which was initially misdiagnosed as a parotid tumor. CT revealed a well-defined mass demonstrating higher attenuation than the adjacent soft tissue with marked expansion of the mandibular condyle. MRI clearly delineated the extent of the lesion which had very low signal intensity on both T1W and T2W sequences due to the effect of hemosiderin. The usefulness of these imaging procedures in diagnosis of PVNS is discussed.


Assuntos
Sinovite/diagnóstico por imagem , Transtornos da Articulação Temporomandibular/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Imageamento por Ressonância Magnética , Côndilo Mandibular/diagnóstico por imagem , Côndilo Mandibular/patologia , Doenças Mandibulares/diagnóstico por imagem , Doenças Mandibulares/patologia , Pessoa de Meia-Idade , Neoplasias Parotídeas/diagnóstico , Sinovite/patologia , Transtornos da Articulação Temporomandibular/patologia , Tomografia Computadorizada por Raios X
13.
Org Lett ; 1(6): 909-12, 1999 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-10823221

RESUMO

[formula: see text] In this, the first of two letters, we outline our overall strategy for the total synthesis of phorboxazoles A (1) and B (2), rare oxazole-containing macrolides possessing extraordinary antimitotic activity, and describe the assembly of a C(3-19) subtarget (-)-5 for the total synthesis of phorboxazole A. The synthesis of (-)-5 was achieved in 15 linear steps (12% overall yield), exploiting a modification of the Petasis-Ferrier rearrangement to construct the C(11-15) cis-tetrahydropyran. Dimethylaluminum chloride (Me2AlCl) proved to be the Lewis acid of choice for the Petasis-Ferrier rearrangement.


Assuntos
Compostos Heterocíclicos de 4 ou mais Anéis/síntese química , Oxazóis/síntese química , Ácidos/química , Oxirredução
14.
AAOHN J ; 46(4): 169-78; quiz 179-80, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9668724

RESUMO

1. The occupational health nurse must understand the prehospital principles for treatment of burn victims. This understanding promotes appropriate burn management which can impact mortality and morbidity. 2. The most important concept in emergency management of burn victims is scene safety, the nurse's safety, and ultimately, the victim's safety. 3. All burn victims need to be managed as trauma victims with a primary and secondary survey to rapidly determine life threatening problems and whether other injuries are present. 4. Familiarity with the structures and functions of the skin is imperative to understand the pathophysiology and consequences of burn injuries.


Assuntos
Queimaduras/enfermagem , Tratamento de Emergência/métodos , Enfermagem do Trabalho/métodos , Doença Aguda , Algoritmos , Queimaduras/classificação , Educação Continuada em Enfermagem , Humanos , Avaliação em Enfermagem , Encaminhamento e Consulta , Triagem/métodos
15.
Int J Radiat Oncol Biol Phys ; 41(4): 835-41, 1998 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-9652846

RESUMO

PURPOSE: To investigate the effects of radiation on anorectal function in patients with carcinoma of the uterine cervix. METHODS AND MATERIALS: Anorectal manometry was carried out on 24 patients (complication group) with late radiation proctitis. All of the manometric data from these patients were compared with those from 24 age-matched female volunteers (control group), in whom radiation treatment had not yet been performed. RESULTS: Regardless of the severity of proctitis symptoms, 25% of patients demonstrated all their manometric data within the normal range, but 75% of patients exhibited one or more abnormal manometric parameters for sensory or motor functions. Six patients (25%) had an isolated sensory dysfunction, eight patients (33.3%) had an isolated motor dysfunction, and four patients (16.7%) had combined disturbances of both sensory and motor functions. The maximum tolerable volume, the minimal threshold volume, and the urgent volume in the complication group were significantly reduced compared with those in the control group. The mean squeeze pressure in the complication group was significantly reduced, whereas the mean resting pressure and anal sphincter length were unchanged. CONCLUSIONS: Physiologic changes of the anorectum in patients with late radiation proctitis seem to be caused by a variety of sensory and/or motor dysfunctions in which many different mechanisms are working together. The reduced rectal reservoir capacity and impaired sensory functions were crucial factors for functional disorder in such patients. In addition, radiation damage to the external anal sphincter muscle was considered to be an important cause of motor dysfunction.


Assuntos
Canal Anal/fisiopatologia , Proctite/fisiopatologia , Lesões por Radiação/fisiopatologia , Transtornos de Sensação/fisiopatologia , Neoplasias do Colo do Útero/radioterapia , Adulto , Idoso , Canal Anal/efeitos da radiação , Feminino , Humanos , Manometria , Pessoa de Meia-Idade
16.
AAOHN J ; 45(3): 137-45; quiz 146-8, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9146115

RESUMO

1. It is important for the occupational health nurse to be aware of and understand the mechanism of injury and forces involved in a trauma event. This understanding provides insight into the potential injuries that may be present even if the victim appears unhurt. 2. The primary survey is designed to rapidly determine life threatening problems and provide immediate interventions. 3. The secondary survey is a more detailed, head to toe assessment of the victim to determine if other injuries are present. This part of the examination helps determine more subtle findings.


Assuntos
Avaliação em Enfermagem/métodos , Enfermagem do Trabalho/métodos , Ferimentos e Lesões/enfermagem , Emergências , Humanos , Exame Físico , Triagem , Ferimentos e Lesões/etiologia
18.
Ann Acad Med Singap ; 17(4): 482-5, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3265604

RESUMO

410 cases of psoriasis [282 males (68%) and 127 females (31%)] were interviewed and examined to study the nail changes. The prevalence of nail changes was 78.0% (males = females). Common changes were pitting (67.5%) and onycholysis (67.2%). Dystrophy of varying degrees occurred in 35.0%, subungual hyperkeratosis in 24.7%, discoloration in 18.4%, loss of nails in 2.8% and pustulation in 1.3%. Pitting and onycholysis was the most common combination (45.6%). Nail changes were significantly more common in patients who have moderate to severe psoriasis as compared with patients with mild psoriasis; in patients who have psoriasis for greater than 5 years as compared with patients who have psoriasis for less than 5 years; and in patients older than age 50 as compared with those aged less than 50. A definite correlation was found between the prevalence of nail changes and the presence of scalp and periungual psoriasis, and the presence of joint involvement.


Assuntos
Doenças da Unha/complicações , Psoríase/complicações , Artrite/complicações , Artrite/epidemiologia , Artrite/etnologia , China/etnologia , Estudos Transversais , Feminino , Humanos , Índia/etnologia , Malásia/etnologia , Masculino , Doenças da Unha/epidemiologia , Doenças da Unha/etnologia , Singapura
19.
Proc Natl Acad Sci U S A ; 85(8): 2449-53, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3282230

RESUMO

In order to define the protease domain of human immunodeficiency virus 1, various regions of the pol open reading frame were cloned and expressed in Escherichia coli. Antiserum directed against the conserved retroviral protease active site was used to identify pol precursor and processed species containing the presumed protease domain. The smallest product that accumulates is about 11 kDa as measured by NaDodSO4/PAGE. This size agrees with that predicted from the presence in this region of two Phe-Pro sequences, which is one of the cleavage sites recognized by HIV protease. DNA encoding only the predicted 11-kDa protein was cloned, bypassing the need for autoprocessing, and the protein was expressed to a high level in E. coli. This form is active as demonstrated by its ability to specifically cleave protease-deficient pol protein in vivo in E. coli. Extracts of E. coli containing the 11-kDa protease also process human immunodeficiency virus gag substrates in vitro. These results demonstrate that the 11-kDa protease is sufficient for enzymatic activity and are consistent with a major role for this form in virus maturation.


Assuntos
Endopeptidases/metabolismo , HIV/enzimologia , Clonagem Molecular , Análise Mutacional de DNA , Endopeptidases/genética , Escherichia coli , Protease de HIV , Peso Molecular , Precursores de Proteínas/metabolismo , Relação Estrutura-Atividade , Proteínas Virais/metabolismo
20.
J Membr Biol ; 86(2): 99-104, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3875728

RESUMO

A method is described that makes it possible to separate the sodium fluxes through the isolated frog skin into sets characteristic of the cellular and the paracellular pathway, respectively. If there are two significant pathways for the ion, and if they differ with respect to flux ratio as well as mean passage time, the flux ratios for the individual pathways can be obtained from a set of inward and outward tracer fluxes, covering the time from the addition of the tracers until the achievement of constant fluxes in both directions.


Assuntos
Pele/metabolismo , Sódio/metabolismo , Animais , Transporte Biológico Ativo , Epitélio/metabolismo , Cinética , Matemática , Modelos Biológicos , Rana temporaria
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