Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 136
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
AIDS Res Ther ; 19(1): 69, 2022 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-36587188

RESUMEN

INTRODUCTION: Incident syphilis leads to changes in plasma HIV-1 RNA and CD4 + T-cell level in people with HIV (PWH) with viraemia. Its effect in PWH on suppressive antiretroviral therapy (ART) is less clear. METHODS: PWH on suppressive ART (plasma HIV-1 RNA < 50copies/mL) followed at the Queen Elizabeth Hospital, Hong Kong, China were regularly screened for syphilis. Their plasma HIV-1 RNA, CD4 + and CD8 + T-cell, and total lymphocyte levels before syphilis, during syphilis, and after successful treatment were compared. RESULTS: Between 2005 and 2020, 288 syphilis episodes from 180 individuals were identified; 287 episodes were related to male, with a median age of 41 at diagnosis; 221 (77%) were syphilis re-infection. The rates of plasma HIV-1 suppression were statistically unchanged across the time-points (97% pre-syphilis, 98% during syphilis, and 99% post-treatment). Total lymphocyte, CD4+ and CD8+ T-cell levels decreased during incident syphilis (p<0.01), and rebounded post-treatment (p<0.01). VDRL titre was associated with declines in CD4+ T-cell (p=0.045), CD8+ T-cell (p=0.004), and total lymphocyte levels (p=0.021). Pre-syphilis CD4/CD8 ratio was associated with increases in CD8+ T-cell (p=0.001) and total lymphocyte levels (p=0.046) during syphilis. Syphilis re-infection was associated with an increase in total lymphocyte level (p=0.037). In the multivariable analysis, only pre-syphilis CD4/CD8 ratio was independently associated with increases in CD8+ T-cell (p=0.014) and total lymphocyte levels (p=0.039) during syphilis. CONCLUSIONS: Among virally-suppressed PWH, total lymphocyte, CD4+, and CD8+ T-cell levels declined during incident syphilis but rebounded post-treatment. The status of plasma HIV suppression was unaffected by syphilis.


Asunto(s)
Infecciones por VIH , Seropositividad para VIH , VIH-1 , Sífilis , Humanos , Masculino , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Sífilis/epidemiología , Reinfección/complicaciones , Linfocitos T CD4-Positivos , Seropositividad para VIH/complicaciones , ARN , Terapia Antirretroviral Altamente Activa , Carga Viral , Recuento de Linfocito CD4
3.
Dis Esophagus ; 26(3): 231-6, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22624653

RESUMEN

Achalasia is a rare primary motility disorder of esophagus; treatments include endoscopic balloon dilatation (EBD) and laparoscopic Heller's cardiomyotomy (LC). This study compared EBD versus LC for treatment of achalasia with focus on quality of life (QoL) and prevalence of post-treatment gastroesophageal reflux disease. This was a retrospective cohort study of all patients diagnosed with achalasia older than 16 treated with either EBD or LC from January 1998 to April 2008. Patients' demographic data, comorbidities, postintervention GERD symptoms, QoL, recurrence of dysphagia, reintervention rate, hospital stay, and time to resumption of diet were collected. Sixty-eight patients were recruited into the study (EBD n= 50; LC n= 18). A significant improvement in QoL was found in patients undergoing LC (0.917 vs. 0.807, P= 0.006). A higher proportion of patients treated with EBD developed post-treatment gastroesophageal reflux symptoms (60.5% vs. 43.8%) when compared with LC, although statistically insignificant (P= 0.34). Patients treated with balloon dilatation had a greater percentage of recurrence of dysphagia (55.1% vs. 26.7%; P= 0.235) and need of reintervention (42.1% vs. 9.1%; P= 0.045). However, these patients had a shorter median hospital stay (1d [range 0-4]) and earlier resumption of diet (0d [range 0-3]). Although EBD is associated with a quicker perioperative recovery, LC accomplished a better QoL, lower incidence of recurrence of dysphagia, and need of reintervention after treatment for achalasia.


Asunto(s)
Cardias/cirugía , Cateterismo/métodos , Trastornos de Deglución/prevención & control , Acalasia del Esófago/cirugía , Esofagoscopía/métodos , Laparoscopía/métodos , Calidad de Vida , Adulto , Estudios de Cohortes , Dieta , Dilatación/métodos , Acalasia del Esófago/psicología , Acalasia del Esófago/terapia , Femenino , Estudios de Seguimiento , Reflujo Gastroesofágico/etiología , Hospitalización , Humanos , Tiempo de Internación , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Recurrencia , Retratamiento , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
4.
Hong Kong Med J ; 19(6): 545-8, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24310663

RESUMEN

Influenza and pneumococcus co-infection can cause severe morbidity and mortality. Usually, this entails influenza A, while infection by influenza B is rarely serious. The literature describes influenza A epidemics leading to prolific loss of lives, notably the 1918 epidemic was blamed for the deaths of 40 to 50 million people. In this report, four patients were infected by influenza B during the influenza epidemic of 2011/12 in Hong Kong. All of them were previously healthy and had no chronic diseases; they were admitted to the hospital due to influenza-like symptoms. They rapidly deteriorated with multi-organ failure, and were subsequently diagnosed to be infected with influenza B and streptococci that gave rise to severe pneumonia. Three of them were infected with Streptococcus pneumoniae and one with Streptococcus pyogenes. All of them had leukopenia, septic shock, and acute kidney injury; two of whom died despite aggressive antibiotic treatment and organ support in the intensive care unit. According to the literature, this is the second case report of severe invasive pneumococcal pneumonia secondary to influenza B infection.


Asunto(s)
Gripe Humana/complicaciones , Neumonía/fisiopatología , Infecciones Estreptocócicas/complicaciones , Adulto , Coinfección , Hong Kong , Humanos , Virus de la Influenza B/aislamiento & purificación , Gripe Humana/virología , Masculino , Persona de Mediana Edad , Insuficiencia Multiorgánica/microbiología , Insuficiencia Multiorgánica/virología , Neumonía/microbiología , Neumonía/virología , Índice de Severidad de la Enfermedad , Infecciones Estreptocócicas/microbiología , Streptococcus pneumoniae/aislamiento & purificación , Streptococcus pyogenes/aislamiento & purificación
5.
Hong Kong Med J ; 18(5): 381-7, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23018065

RESUMEN

OBJECTIVE. To assess the effect of a difference in nomenclature for psychiatric illness on perceptions of university students. DESIGN. Cross-sectional study. SETTING. Three local universities in Hong Kong. PARTICIPANTS. A total of 201 university students (undergraduates or postgraduates) were interviewed with a questionnaire. MAIN OUTCOME MEASURES. Score difference between the new and old nomenclature of each disease for each question of the questionnaire, using a 5-point Likert scale and an integrated score difference for each disease. RESULTS. Of the seven diseases investigated, six yielded a significant yet mild increase in positive perceptions with the new nomenclature. These diseases included schizophrenia (integrated score difference: +0.158, P<0.001), neurasthenia (integrated score difference: +0.117, P<0.001), paranoia (integrated score difference: +0.209, P<0.001), personality disorder (integrated score difference: +0.282, P<0.001), attention deficit hyperactivity disorder (integrated score difference: +0.086, P=0.005), and bipolar disorder (integrated score difference: +0.154, P<0.001). Epilepsy showed a negative perception with its new nomenclature (integrated score difference: -0.119, P<0.001). CONCLUSIONS. The new nomenclature system for psychiatric diseases achieves more positive perceptions among the university students than the old nomenclature. Epilepsy was the exception for which the old nomenclature conferred a more positive perception. Further studies on this topic involving a more general population should be advocated to confirm the improvements in perception with the new naming system for psychiatric diseases.


Asunto(s)
Trastornos Mentales , Estudiantes/psicología , Terminología como Asunto , Adolescente , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Estudios Prospectivos , Encuestas y Cuestionarios , Universidades , Adulto Joven
6.
J Trauma ; 70(5): 1128-33, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21336195

RESUMEN

BACKGROUND: In 1994, the Hong Kong Special Administrative Region (HKSAR) introduced plans to implement a trauma system based on the recommendations outlined by Professor Donald Trunkey in his report to the local Hospital Authority. Five government-subsidized public hospitals were subsequently designated as trauma centers in 2003. This article reviews the initial experience in these five centers. METHODS: Prospective trauma registries from January 2004 to December 2008 were reviewed. Primary clinical outcome measures were hospital mortality. The Trauma and Injury Severity Score methodology was used for benchmarking with the Major Trauma Outcome Study (MTOS) database. RESULTS: The majority (83.3%) of the 10,462 patients suffered from blunt trauma. Severe injury, defined as Injury Severity Score>15, occurred in 29.7% of patients. The leading causes of trauma were motor vehicle collisions and falls, with crude hospital mortality rates of 6.9% and 10.7%, respectively. The M-statistic was 0.95, indicating comparable case-mix with the MTOS. The worst outcome occurred in the first year. Significant improvement was seen in patients with penetrating injuries. By 2008, these patients had significantly higher survival rates than expected (Z-statistic=0.85). Although the overall mortality rates for blunt trauma were higher than expected, the difference was no longer statistically significant from the second year onward. CONCLUSIONS: The case-mix of trauma patients in the HKSAR is comparable with that of the MTOS. A young trauma system relatively unburdened by dissimilar reimbursement and patient access issues may achieve significant improvement and satisfactory patient outcomes. Our findings may serve as a useful benchmark for HK and other Southeast Asian cities and trauma systems to establish local coefficients for future evaluations.


Asunto(s)
Planificación en Salud , Sistema de Registros/estadística & datos numéricos , Centros Traumatológicos/organización & administración , Heridas no Penetrantes/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Hong Kong/epidemiología , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Índices de Gravedad del Trauma , Heridas no Penetrantes/diagnóstico , Heridas no Penetrantes/epidemiología , Adulto Joven
9.
Ultrasound Obstet Gynecol ; 32(1): 87-90, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18548478

RESUMEN

OBJECTIVES: To determine, in patients who have undergone bilateral pelvic lymphadenectomy for gynecological cancer, the incidence of lymphocyst formation, their change in size with time, risk factors and correlation with symptoms. METHODS: This was a prospective observational study of 108 patients undergoing bilateral pelvic lymphadenectomy for gynecological cancer in our unit. We performed serial three-dimensional (3D) ultrasound assessment at 2 and 6 weeks and 3, 6, 9 and 12 months after surgery. Before each ultrasound assessment, symptoms were recorded and a physical examination was performed. RESULTS: Forty-eight (44.4%) patients had unilateral or bilateral lymphocysts detected during the follow-up period; 26 were on the left side, 16 were on the right side and six were bilateral. In 39 (81.2%) of the patients, the lymphocysts were first noted 2 weeks after the operation. In nine (18.8%) the lymphocysts persisted until 12 months after surgery. There was no association between lymphocyst formation and diagnosis, type of operation performed, surgeon, operative blood loss, adjuvant radiotherapy and number of lymph nodes removed. Four lymphocysts were detected by physical examination before the ultrasound diagnosis. There was no association between lymphocyst and symptoms, including pain over the abdomen, pelvis, thigh, legs or back, lymphedema, fever or symptoms of cystitis. Only one patient developed an infection of the lymphocyst, which required surgical intervention. CONCLUSION: Lymphocyst formation is common following bilateral pelvic lymphadenectomy. Most patients with lymphocysts are asymptomatic and the development of major complications is rare.


Asunto(s)
Imagenología Tridimensional , Escisión del Ganglio Linfático/efectos adversos , Linfocele/diagnóstico por imagen , Ultrasonografía Doppler en Color/métodos , Femenino , Neoplasias de los Genitales Femeninos/cirugía , Hong Kong/epidemiología , Humanos , Linfocele/epidemiología , Linfocele/etiología , Dolor/etiología , Pelvis/diagnóstico por imagen , Estudios Prospectivos , Factores de Riesgo
10.
Eur J Obstet Gynecol Reprod Biol ; 130(2): 165-8, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16567034

RESUMEN

BACKGROUND: The incidence of birth trauma and birth asphyxia related to instrumental deliveries in our obstetric unit was high (2.8%) in 1998-1999. A study was performed in 2000 to identify the risk factors. Unexpectedly, the incidence (0.6%) was reduced significantly during the study period. We attributed this phenomenon to the famous Hawthorne effect (tendency to improve performance because of awareness of being studied). OBJECTIVES: The objectives were to study whether there is a continued reduction in the incidence of birth trauma and birth asphyxia related to instrumental deliveries in the post-study period (2001-2003) and to investigate the presence of underlying confounding factors apart from the Hawthorne effect. METHOD: To compare the hospital obstetric statistics among the pre-study period (1998-1999), the study period (2000) and the post-study period (2001-2003), in particular the incidence of birth trauma and birth asphyxia related to instrumental deliveries, the instrumental delivery rate, the overall Caesarean section rate, the Caesarean section rate for no progress of labour, the incidence of failed instrumental delivery, the incidence of attempted instrumental delivery in the operating theatre, and incidence of direct second-stage Caesarean sections. RESULTS: The incidence of birth trauma and birth asphyxia related to instrumental deliveries (0.6%) during the study period (2000) was significantly lower than that (2.8%) during the pre-study period (1998-1999; RR 0.27, 95% CI 0.11-0.70). This phenomenon continued into the post-study period (2001-2003) when the incidence of 1.0% was similarly lower than that in the pre-study period (RR 0.35, 95% CI 0.20-0.64). The instrumental delivery rate decreased further in the post-study period (13.5%) compared with those in the study (16.6%) and pre-study (19.5%) periods (RR 0.81, 95% CI 0.75-0.89 and RR 0.69, 95% CI 0.65-0.74, respectively). There was a marked increase in the direct second-stage Caesarean section rate in the post-study period (7.1%) compared to those in the study (0.4%) and pre-study (0.7%) periods (RR 15.9, 95% CI 5.05-49.73 and RR 9.77, 95% CI 5.28-18.08, respectively). CONCLUSION: A change in obstetric practice was identified that may explain the continued reduction in the incidence of birth trauma and birth asphyxia related to instrumental deliveries in the post-study period.


Asunto(s)
Asfixia Neonatal/epidemiología , Traumatismos del Nacimiento/epidemiología , Extracción Obstétrica/efectos adversos , Hospitales Universitarios/estadística & datos numéricos , Asfixia Neonatal/prevención & control , Traumatismos del Nacimiento/prevención & control , China/epidemiología , Parto Obstétrico/estadística & datos numéricos , Modificador del Efecto Epidemiológico , Extracción Obstétrica/estadística & datos numéricos , Femenino , Humanos , Recién Nacido , Morbilidad , Guías de Práctica Clínica como Asunto , Embarazo , Factores de Riesgo
12.
Hong Kong Med J ; 12(2): 94-8, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16603774

RESUMEN

OBJECTIVE: To review the use of episiotomy during vaginal delivery in Hong Kong public hospitals. DESIGN: Prospective observational survey. SETTING: Public hospitals, Hong Kong. PARTICIPANTS: Women who underwent normal vaginal delivery of a singleton foetus with cephalic presentation. MAIN OUTCOME MEASURES: Number of women having an episiotomy, severe-degree (third- or fourth-degree) tear, other types of tear, blood loss at delivery, postpartum haemorrhage, need for blood transfusion, puerperal pyrexia, wound infection, gaping wound that required suture removal, and drainage or resuturing of a perineal wound. RESULTS: Between 1 January and 31 March 2003, there were 6222 singleton spontaneous normal vaginal deliveries in the public hospitals of Hong Kong. Of the 6167 women in whom the status of the perineum was known, episiotomy was performed in 5274 (85.5%). Primiparous women were more likely to undergo episiotomy at delivery than multiparous women (97.9% vs 71.4%). Women with episiotomy had significantly less perineal tearing of any kind than those without. The occurrence of any type of perineal tear and severe-degree (third- or fourth-degree) tear was significantly lower in primiparous women who had an episiotomy than those without (P<0.05). Women with episiotomy had increased mean blood loss at delivery but other complications were not significantly increased. CONCLUSIONS: In Hong Kong, episiotomy is routinely performed during normal vaginal delivery. It is associated with a significantly lower overall rate of perineal tearing. This study was observational, nonetheless the occurrence of other complications was likely to increase when episiotomy was performed. Firm evidence from several randomised controlled studies shows that routine episiotomy is unjustified and possibly harmful. Routine episiotomy should not be promoted in Hong Kong without further randomised controlled study.


Asunto(s)
Episiotomía/efectos adversos , Adolescente , Adulto , Estudios de Casos y Controles , Episiotomía/estadística & datos numéricos , Femenino , Hong Kong/epidemiología , Humanos , Persona de Mediana Edad , Complicaciones del Trabajo de Parto/epidemiología , Complicaciones del Trabajo de Parto/etiología , Paridad , Perineo/lesiones , Pautas de la Práctica en Medicina , Embarazo
13.
Leukemia ; 6(3): 199-203, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1564956

RESUMEN

Tartrate-resistant acid phosphatase (TRAcP) is a reliable cytochemical marker for the diagnosis of hairy cell leukemia (HCL). The enzyme has been the subject of much biochemical investigation yet its function in the hairy cells (HC) is still unknown. Two TRAcPs have been purified from HCL spleen tissues by a series of chromatographic separations. The two enzymes, provisionally called peak 1 and peak 2, had specific activities of greater than 600 U/mg and 800 U/mg respectively when p-nitrophenyl phosphate (p-NPP) was used as substrate and had Km values in the range of 1 to 5 mM p-NPP. The two TRAcPs had the same substrate specificities and inhibitor sensitivities, therefore could be isoforms of the same enzyme. Their pH optima were between 5 and 6 for all substrates tested including the phosphotyrosine-containing peptide, Raytide, which was still hydrolyzed efficiently at neutral pH. Neither phosphoserine nor phosphoserine-containing casein were hydrolyzed by either enzyme. The TRAcPs of HC may thus be capable of functioning as protein-tyrosine phosphatases (PTP). High activity of a PTP could regulate the activities of protein-tyrosine kinases and thereby influence the growth and differentiation of the hairy cells.


Asunto(s)
Fosfatasa Ácida/metabolismo , Isoenzimas/metabolismo , Leucemia de Células Pilosas/enzimología , Proteínas Tirosina Fosfatasas/metabolismo , Tartratos/farmacología , Fosfatasa Ácida/antagonistas & inhibidores , Fosfatasa Ácida/aislamiento & purificación , Electroforesis en Gel de Poliacrilamida , Humanos , Concentración de Iones de Hidrógeno , Hidrólisis , Isoenzimas/antagonistas & inhibidores , Isoenzimas/aislamiento & purificación , Leucemia de Células Pilosas/patología , Bazo/enzimología , Bazo/patología , Especificidad por Sustrato , Fosfatasa Ácida Tartratorresistente
14.
Hand Surg ; 10(2-3): 159-68, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16568509

RESUMEN

This article describes the development of a proximal interphalangeal (PIP) joint prosthesis based on the principles of replicating anatomical surface components, the use of macrolocking intramedullary stem and the use of a cobalt-chrome alloy material. The design features are intended to obtain an optimal range of motion while retaining stability and longevity. The final prototype, for which a patent has been filed, is described.


Asunto(s)
Articulaciones de los Dedos/cirugía , Prótesis e Implantes , Aleaciones de Cromo , Humanos , Ensayo de Materiales
15.
Am J Hosp Palliat Care ; 32(5): 549-54, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24819729

RESUMEN

INTRODUCTION: End-of-life care is affected by the attitude and cultural influence of doctors. METHODS: To investigate the attitudes and practices of doctors on end-of-life care by questionnaire survey in 2004 and 2008. RESULTS: In 2004, 31.7% of the respondents agreed that they "do not attempt resuscitation" (DNAR) form was useful and it rose to 54.4% in 2008. A higher proportion of respondents in 2008 claimed that they signed the DNAR form for documentation and accepted withholding noninvasive life-sustaining treatment compared to 2004. In 2004, 50% of the respondents regarded their training and education on handling DNAR issue as inadequate. CONCLUSION: Documentation by DNAR form is gaining wider acceptance. Many doctors are expected to have more training and coaching on communication for handling such sensitive issues.


Asunto(s)
Actitud del Personal de Salud , Médicos/psicología , Órdenes de Resucitación/psicología , Cuidado Terminal/psicología , Factores de Edad , China , Estudios Transversales , Humanos , Estudios Longitudinales , Comodidad del Paciente , Pautas de la Práctica en Medicina
16.
Gene ; 60(2-3): 191-6, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-2965059

RESUMEN

A human liver cDNA library in lambda gt11 was screened with polyclonal antiserum to human acid phosphatase isoenzyme 2a/4. About eleven positive clones have been obtained. Two clones, lambda Hap21 and lambda Hap22 were further characterized: clone lambda Hap21 contained a 0.8-kb cDNA insert and clone lambda Hap22 a 1.8-2.0-kb insert. XbaI digestion of lambda Hap22 generated two fragments of 1.0 and 0.9 kb. BglII digestion resulted in a 1.2-kb fragment and several smaller fragments of undetermined size. Clone lambda Hap22 contained all the genes carried by lambda gt11(lac5cI857nin5Sam100) and the 2-kb insert. An Escherichia coli(lambda Hap22) lysogen was generated, and its acid phosphatase activity was approximately ten-fold higher than that in the control nonlysogenic lysate. Western-blot analysis of total proteins present in this E. coli(lambda Hap22) lysate revealed that the non-induced lambda Hap22 prophage directed the synthesis of an approx. 175-kDa protein. This protein was recognized by antibody to the human acid phosphatase isoenzyme 2a/4 and anti-beta-galactosidase and was produced only upon induction with IPTG. These results indicated that lambda Hap22 carried a major portion of the gene coding for the human acid phosphatase isoenzyme 2a and/or 4 and this protein fragment of acid phosphatase was sufficient to manifest enzymatic activity.


Asunto(s)
Fosfatasa Ácida/genética , ADN/genética , Isoenzimas/genética , Próstata/enzimología , Fosfatasa Ácida/inmunología , Especificidad de Anticuerpos , Bacteriófago lambda/genética , Clonación Molecular , Escherichia coli/genética , Genes , Humanos , Isoenzimas/inmunología , Masculino
17.
Free Radic Biol Med ; 15(4): 453-7, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8225027

RESUMEN

The kinetic properties of ascorbic acid oxidation by light-activated melanin granules demonstrate the presence of a specific reactive site on the melanin granule saturable by ascorbic acid. Increased light intensity increased the Vmax and reduced the Km of this reaction, indicating increased affinity of the active site for ascorbic acid. The kinetics of this reaction are not markedly changed in a reduced-oxygen environment. Ascorbic acid oxidation is competitively inhibited by isoascorbic acid, an epimer of ascorbic acid, while other tested reducing agents are inactive. The Ki for isoascorbic acid is 1 mM, about the same as the Km of ascorbic acid.


Asunto(s)
Ácido Ascórbico/metabolismo , Luz , Melaninas/metabolismo , Animales , Bovinos , Radicales Libres , Cinética , Oxidación-Reducción , Epitelio Pigmentado Ocular/metabolismo
18.
J Histochem Cytochem ; 33(5): 379-83, 1985 May.
Artículo en Inglés | MEDLINE | ID: mdl-3886778

RESUMEN

An antiserum specific to esterase Ib was produced in a rabbit. The antigen-antibody reaction was visualized by the strong esterase activity in the precipitin band in Ouchterlony double diffusion and immunoelectrophoresis. Immunohistochemical procedure demonstrated strong staining in the monocyte-infiltrated splenic sections and tissue sections of true histiocytic lymphoma. Negative results were observed in T- and B-cell lymphomas, granulocytic sarcoma, and chronic granulocytic leukemia. This antibody may be useful for the identification of monocytes and histocytes in paraffin-embedded tissue sections.


Asunto(s)
Esterasas/inmunología , Histocitoquímica/métodos , Monocitos/enzimología , Animales , Especificidad de Anticuerpos , Histiocitos/patología , Técnicas para Inmunoenzimas , Leucemia Mieloide/patología , Linfoma/patología , Monocitos/patología , Conejos
19.
Invest Ophthalmol Vis Sci ; 24(7): 862-7, 1983 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6862792

RESUMEN

Both reduced and oxidized ascorbates were measured in aqueous, neural retina, and pigment epithelium-choroid complex (PE-C) of pigmented guinea pigs. Normal values for total ascorbate of 16 mg/dl in aqueous, 22 mg/dl in neural retina, and 7 mg/dl in PE-C were found. After mild photic damage caused by varying lengths of exposure of 10,000 to 20,000 lux of fluorescent lighting, reduced ascorbate concentrations generally decreased in the neural retina, while oxidized ascorbate generally increased in PE-C. In both normal and light-exposed retinas, reduced ascorbate was predominant in the neural retina, and oxidized ascorbate was predominant in the PE-C. Histochemical localization of reduced ascorbate occurred in the Müller cell fibers and at the apices of the retinal pigment epithelium.


Asunto(s)
Ácido Ascórbico/metabolismo , Retina/metabolismo , Animales , Coroides/metabolismo , Cromatografía Líquida de Alta Presión , Ácido Deshidroascórbico/metabolismo , Cobayas , Histocitoquímica , Oxidación-Reducción , Epitelio Pigmentado Ocular/metabolismo , Retina/efectos de la radiación , Retina/ultraestructura , Escorbuto/metabolismo
20.
Invest Ophthalmol Vis Sci ; 36(7): 1306-16, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7775108

RESUMEN

PURPOSE: To identify and synthesize the polymorphonuclear leukocyte chemoattractant(s) released from alkali-degraded corneas. METHODS: Corneas were degraded in 1.0 N NaOH, neutralized, ultrafiltered, and dialyzed. The final active ultrafiltrate was subjected to high-performance liquid chromatography on a Protein PAK I-60 column. The most active fractions were further separated on a mu-Bondapak-C18 and I-60 column in sequence. RESULTS: Fraction 38 from the final I-60 column associated with a 210-nm absorption peak and elicited a polarization and chemotactic response from polymorphonuclear leukocytes. The loss of polarization activity in fraction 38 after exposure to prolidase suggests that this peptide contains a Pro-X (X = amino acid) peptide bond. The amino acid composition of fraction 38 was 35% glycine and 53% proline. Peptide sequence analysis was unable to establish a primary sequence even though Picotag analysis showed the presence of large amounts of the two amino acids. Mass spectrometry revealed only two molecular species of 312 MWt and 284 MWt. Tripeptides were synthesized using all possible amino acid permutations of 2 Pro and 1 Gly and tested in the polarization and chemotactic assays. These techniques demonstrated that n-acetyl-Pro-Gly-Pro, and to a lesser degree n-methyl-Pro-Gly-Pro, were the only synthetic tripeptides with activity similar to the purified chemoattractant. CONCLUSIONS: The data show that the chemotactic peptides, purified from alkali-degraded whole cornea and confirmed with identical synthetic tripeptides, are N-acetyl-Pro-Gly-Pro and N-methyl-Pro-Gly-Pro. Although a number of proteins contain the Pro-Gly-Pro sequence, large amounts of collagen in the cornea suggest this as a major source. The small size and hydrophilic nature of these chemoattractants are predictive of a high degree of diffusibility. These chemoattractants are likely to play a major role in the early neutrophil response after an alkali injury.


Asunto(s)
Quemaduras Químicas/metabolismo , Factores Quimiotácticos/aislamiento & purificación , Córnea/metabolismo , Quemaduras Oculares/metabolismo , Oligopéptidos/aislamiento & purificación , Hidróxido de Sodio/efectos adversos , Secuencia de Aminoácidos , Animales , Bovinos , Factores Quimiotácticos/síntesis química , Factores Quimiotácticos/fisiología , Quimiotaxis de Leucocito/fisiología , Cromatografía Líquida de Alta Presión , Córnea/efectos de los fármacos , Quemaduras Oculares/inducido químicamente , Inmunoensayo de Polarización Fluorescente , Cromatografía de Gases y Espectrometría de Masas , Humanos , Datos de Secuencia Molecular , Peso Molecular , Neutrófilos/fisiología , Oligopéptidos/síntesis química , Oligopéptidos/fisiología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA