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1.
J Neonatal Perinatal Med ; 16(2): 343-348, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37182845

RESUMEN

INTRODUCTION: Although breast milk is considered the optimal nutrition for infants, it is also the primary cause of postnatal cytomegalovirus (CMV) infection. Preterm infants with postnatal CMV infections are susceptible to a variety of life-threatening conditions. CASE SUMMARY: Twin male infants were delivered via emergency caesarian section at 27 weeks' gestation secondary to maternal complete uterine rupture. The Apgar scores at 1 and 5 min were 1 and 1 for the older twin (Twin A) and 0 and 3 for the younger twin (Twin B). Their birth weights were 1203 g (+ 0.65SD) and 495 g (- 3.79SD) respectively. On day 41, laboratory blood test results for Twin B showed a moderate elevation in C-reactive protein (CRP), thrombocytopenia. CMV quantitative polymerase chain reaction (qPCR) tests in Twin B's urine and blood as well as in the mother's breast milk were positive, but stored, dried umbilical cord CMV qPCR tests were negative. Twin B was diagnosed with a postnatal CMV infection secondary to infected breast milk and ganciclovir was commenced on day 52. Treatment was switched to valganciclovir at 74 days of age, but a negative CMV-DNA level in the blood was not achieved. Postnatal CMV infection in this infant led to an exacerbation of pre-existing bronchopulmonary dysplasia (BPD) and he demised at 182 days of age. CONCLUSION: Postnatal cytomegalovirus infections may lead to exacerbations of BPD. Early use of raw breast milk in preterm infants should be done with careful consideration of this potential complication.


Asunto(s)
Displasia Broncopulmonar , Infecciones por Citomegalovirus , Lactante , Femenino , Embarazo , Recién Nacido , Masculino , Humanos , Leche Humana , Recien Nacido con Peso al Nacer Extremadamente Bajo , Recien Nacido Prematuro , Estudios Prospectivos , Infecciones por Citomegalovirus/complicaciones , Infecciones por Citomegalovirus/tratamiento farmacológico , Infecciones por Citomegalovirus/diagnóstico , Citomegalovirus , Transmisión Vertical de Enfermedad Infecciosa
2.
J Int AIDS Soc ; 22(4): e25277, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30983155

RESUMEN

INTRODUCTION: There are few data about the range of strategies used to prevent sexual HIV transmission within gay male serodiscordant couples. We examined HIV prevention strategies used by such couples and compared differences between countries. METHODS: Opposites Attract was a cohort study of male serodiscordant couples in Australia, Brazil and Thailand, from May 2014 (Australia) or May 2016 (Brazil/Thailand) to December 2016. At visits, HIV-positive partners had viral load (VL) tested; HIV-negative partners reported sexual behaviour and perceptions of their HIV-positive partner's VL results. Within-couple acts of condomless anal intercourse (CLAI) were categorized by strategy: condom-protected, biomedically protected (undetectable VL and/or pre-exposure prophylaxis [PrEP]), or not protected by either (HIV-negative partners engaging in insertive CLAI, receptive CLAI with withdrawal, or receptive CLAI with ejaculation). RESULTS: A total of 343 couples were included in this analysis (153 in Australia, 93 in Brazil and 97 in Thailand). Three-quarters of HIV-positive partners were consistently virally suppressed (<200 copies/mL) during follow-up, and HIV-negative partners had correct perceptions of their partner's VL result for 76.5% of tests. One-third of HIV-negative partners used daily PrEP during follow-up. Over follow-up, 73.8% of couples had CLAI. HIV-negative partners reported 31,532 acts of anal intercourse with their HIV-positive partner. Of these, 46.7% were protected by condoms, 48.6% by a biomedical strategy and 4.7% of acts were not protected by these strategies. Australian couples had fewer condom-protected acts and a higher proportion of biomedically protected acts than Brazilian and Thai couples. Of the 1473 CLAI acts where the perceived VL was detectable/unknown and were not protected by PrEP (4.7% of all acts), two-thirds (n = 983) were when the HIV-negative partner was insertive (strategic positioning). Of the 490 acts when the HIV-negative partner was receptive, 261 involved withdrawal and 280 involved ejaculation. Thus, <1% of acts were in the highest risk category of receptive CLAI with ejaculation. CONCLUSIONS: Couples used condoms, PrEP or perceived undetectable VL for prevention in the majority of anal intercourse acts. Only a very small proportion of events were not protected by these strategies. Variation between countries may reflect differences in access to HIV treatment, education, knowledge and attitudes.


Asunto(s)
Infecciones por VIH/prevención & control , Infecciones por VIH/psicología , Homosexualidad Masculina/estadística & datos numéricos , Adulto , Australia/epidemiología , Brasil/epidemiología , Estudios de Cohortes , Condones/estadística & datos numéricos , Infecciones por VIH/transmisión , Homosexualidad Masculina/psicología , Humanos , Masculino , Profilaxis Pre-Exposición , Sexo Seguro , Conducta Sexual , Parejas Sexuales , Tailandia/epidemiología , Carga Viral , Adulto Joven
3.
Front Public Health ; 6: 151, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29896468

RESUMEN

Background: Pre-exposure prophylaxis (PrEP) is the use of HIV anti-retroviral therapy to prevent HIV transmission in people at high risk of HIV acquisition. PrEP is highly efficacious when taken either daily, or in an on-demand schedule. In Australia co-formulated tenofovir-emtricitabine is registered for daily use for PrEP, however, this co-formulation is not listed yet on the national subsidized medicines list. We describe a study protocol that aims to demonstrate if the provision of PrEP to up to 3800 individuals at risk of HIV in Victoria, Australia reduces HIV incidence locally by 25% generally and 30% among GBM. Methods: PrEPX is a population level intervention study in Victoria, Australia in which generic PrEP will be delivered to 3800 individuals for up to 36 months. Study eligibility is consistent with the recently updated 2017 Australian PrEP guidelines. Participants will attend study clinics, shared care clinics, or outreach clinics for quarterly HIV/STI screening, biannual renal function tests and other clinical care as required. Study visits and STI diagnoses will be recorded electronically through the ACCESS surveillance system. At each study visit participants will be invited to complete behavioral surveys that collect demographics and sexual risk data. Diagnosis and behavioral data will be compared between PrEPX participants and other individuals testing within the ACCESS surveillance system. A subset of participants will complete in depth surveys and interviews to collect attitudes, beliefs and acceptability data. Participating clinics will provide clinic level data on implementation and management of PrEPX participants. The population level impact on HIV incidence will be assessed using Victorian HIV notification data. Discussion: This study will collect evidence on the real world impact of delivery of PrEP to 3800 individuals at risk of acquiring HIV in Victoria. This study will provide important information for the broader implementation of PrEP planning upon listing of the tenofovir-emtricitabine on the national subsidized list of medicines. The study is registered on the Australian New Zealand Clinical Trials Registry (ACTRN12616001215415).

4.
AIDS ; 32(1): 35-48, 2018 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-29135584

RESUMEN

OBJECTIVES: We quantified concomitant medication polypharmacy, pharmacokinetic and pharmacodynamic interactions, adverse effects and adherence in Australian adults on effective antiretroviral therapy. DESIGN: Cross-sectional. METHODS: Patients recruited into a nationwide cohort and assessed for prevalence and type of concomitant medication (including polypharmacy, defined as ≥5 concomitant medications), pharmacokinetic or pharmacodynamic interactions, potential concomitant medication adverse effects and concomitant medication adherence. Factors associated with concomitant medication polypharmacy and with imperfect adherence were identified using multivariable logistic regression. RESULTS: Of 522 participants, 392 (75%) took a concomitant medication (mostly cardiovascular, nonprescription or antidepressant). Overall, 280 participants (54%) had polypharmacy of concomitant medications and/or a drug interaction or contraindication. Polypharmacy was present in 122 (23%) and independently associated with clinical trial participation, renal impairment, major comorbidity, hospital/general practice-based HIV care (versus sexual health clinic) and benzodiazepine use. Seventeen participants (3%) took at least one concomitant medication contraindicated with their antiretroviral therapy, and 237 (45%) had at least one pharmacokinetic/pharmacodynamic interaction. Concomitant medication use was significantly associated with sleep disturbance and myalgia, and polypharmacy of concomitant medications with diarrhoea, fatigue, myalgia and peripheral neuropathy. Sixty participants (12%) reported imperfect concomitant medication adherence, independently associated with requiring financial support, foregoing necessities for financial reasons, good/very good self-reported general health and at least 1 bed day for illness in the previous 12 months. CONCLUSION: In a resource-rich setting with universal healthcare access, the majority of this sample took a concomitant medication. Over half had at least one of concomitant medication polypharmacy, pharmacokinetic or pharmacodynamic interaction. Concomitant medication use was associated with several adverse clinical outcomes.


Asunto(s)
Antirretrovirales/uso terapéutico , Interacciones Farmacológicas , Infecciones por VIH/tratamiento farmacológico , Cumplimiento de la Medicación , Polifarmacia , Adulto , Anciano , Antirretrovirales/efectos adversos , Antirretrovirales/farmacocinética , Australia , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad
5.
AIDS ; 31(12): 1709-1714, 2017 07 31.
Artículo en Inglés | MEDLINE | ID: mdl-28700394

RESUMEN

OBJECTIVE: HIV preexposure prophylaxis (PrEP) decreases risk of HIV acquisition; however, its efficacy is closely dependent on adherence. There is also concern that the preventive effect of PrEP may be offset by risk compensation, notably an increase in condomless anal sex. DESIGN: Multisite, open-label demonstration study that recruited people at current or recent risk of HIV infection in Melbourne, Australia. METHODS: Participants were recruited from three general practice clinics and one sexual health clinic in Melbourne and consented to take daily tenofovir/emtricitabine (TFV/FTC) for 30 months. Sexual practice data, HIV and sexually transmitted infection (STI) test results were collected at baseline and 3-monthly during follow-up. PrEP adherence was evaluated by self-report at clinical visits, online surveys, refill-based assessments and dried blood spot testing. We present a 12-month interim analysis. RESULTS: A total of 114 people were recruited. We observed a significant decline in condom use which occurred concomitantly with a significant increase in STIs over the first 12 months of PrEP. Incidence (per 100 person-years) of any STI was 43.2 and 119.8 at months 0-3 and 3-12, respectively [incidence rate ratio 2.77 (1.52, 5.56)]. Adherence to PrEP medication was high by all measures, including 6 month TFV/FTC levels in dried blood spot. CONCLUSION: We found a significant reduction in condom use and an increase in STIs over the first 12 months of follow-up. High medication adherence rates occurring with a decline in condom use and a rise in STIs, suggest that prevention, early detection and treatment of STIs is a chief research priority in the current era of HIV PrEP.


Asunto(s)
Condones/estadística & datos numéricos , Cumplimiento de la Medicación , Profilaxis Pre-Exposición/métodos , Profilaxis Pre-Exposición/estadística & datos numéricos , Enfermedades de Transmisión Sexual/epidemiología , Enfermedades de Transmisión Sexual/prevención & control , Adulto , Australia/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad
9.
Kyobu Geka ; 59(2): 149-52, 2006 Feb.
Artículo en Japonés | MEDLINE | ID: mdl-16482911

RESUMEN

A 77-year-old woman with a previous history of median sternotomy and collagen disease, presented with chief complaints of resting dyspnea as a result of recurrent pericardial effusions or restrictive ventilatory impairment. She experienced significant symptom amelioration after undergoing pericardioperitoneal fenestration. We weighed the positive against the negative of various pericardial effusion drainage methods in this study. This operative procedure is not innovative, but favorable because it can be carried out conveniently and safely, enabling early rehabilitation without appreciable postoperative complications.


Asunto(s)
Derrame Pericárdico/cirugía , Técnicas de Ventana Pericárdica , Pericarditis/cirugía , Anciano , Enfermedad Crónica , Femenino , Humanos , Peritoneo/cirugía , Resultado del Tratamiento
10.
J Inherit Metab Dis ; 26(1): 87-8, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12872848

RESUMEN

We performed allopurinol challenge tests to evaluate the metabolic state of a citrullinaemic patient who received a living-relative donor liver transplant. Before transplantation, large amounts of orotic acid and orotidine were excreted during the challenge test. Following transplantation, excretion of these compounds in response to allopurinol was normalised. The challenge test was a safe and useful method to evaluate the metabolic state of the patient.


Asunto(s)
Alopurinol , Antimetabolitos , Citrulina/sangre , Citrulinemia/diagnóstico , Citrulinemia/cirugía , Trasplante de Hígado/fisiología , Niño , Cromatografía Líquida de Alta Presión , Femenino , Humanos , Donadores Vivos
11.
J Res Natl Inst Stand Technol ; 108(4): 299-321, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-27413613

RESUMEN

The cdma2000 system is an evolutionary enhancement of the IS-95 standards which support 3G services defined by the International Telecommunications Union (ITU). cdma2000 comes in two phases: 1XRTT and 3XRTT (1X and 3X indicates the number of 1.25 MHz wide radio carrier channels used and RTT stands for Radio Transmission Technology). The cdma2000 1XRTT, which operates within a 1.25 MHz bandwidth, can be utilized in existing IS-95 CDMA channels as it uses the same bandwidth, while 3XRTT requires the commitment of 5 MHz bandwidth to support higher data rates. This paper describes a software model implementation of the cdma2000 reverse link and its application for evaluating the effect of rake receiver design parameters on the system performance under various multipath fading conditions. The cdma2000 models were developed at the National Institute of Standards and Technology (NIST), using SPW (Signal Processing Worksystem) commercial software tools. The model has been developed in a generic manner that includes all the reverse link six radio configurations and their corresponding data rates, according to cdma2000 specifications. After briefly reviewing the traffic channel characteristics of the cdma2000 reverse link (subscriber to base station), the paper discusses the rake receiver implementation including an ideal rake receiver. It then evaluates the performance of each receiver for a Spreading Rate 3 (3XRTT) operation, which is considered as a true "3G" cdma2000 technology. These evaluations are based on the vehicular IMT-2000 (International Mobile Telecommunication 2000) channel model using the link budget defined in cdma2000 specifications for the reverse link.

12.
Nucl Med Commun ; 23(2): 175-9, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11891473

RESUMEN

We report the estimation of left ventricular systolic pressure (LVSP) by a left ventricular (LV) volume-time curve obtained from electrocardiogram (ECG) gated 99mTc-tetrofosmin single photon emission computed tomography (SPECT) using quantitative gated SPECT (QGS). LVSP was calculated based on the following parameters: LV volumes, velocity and acceleration of LV contraction, aortic valve area and density of blood. The first three parameters can be derived from ECG gated SPECT. In 16 patients, the LV volume-time curve was obtained from ECG gated SPECT by using QGS. LVSP was estimated by the above-mentioned theory. The values of estimated peak LVSP were compared with those measured from a pressure transducer. There was a correlation between the values of peak LVSP estimated by the LV volume-time curve and those measured by pressure transducer (r=0.69, P<0.01). Using QGS, LVSP and the systolic LV pressure-volume relationship could be estimated by the LV volume-time curve.


Asunto(s)
Algoritmos , Imagen de Acumulación Sanguínea de Compuerta/métodos , Función Ventricular Izquierda/fisiología , Presión Ventricular/fisiología , Angina de Pecho/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Cardiovasculares , Infarto del Miocardio/diagnóstico por imagen , Isquemia Miocárdica/diagnóstico por imagen , Compuestos Organofosforados , Compuestos de Organotecnecio , Radiofármacos , Sensibilidad y Especificidad
14.
Transplantation ; 71(10): 1495-7, 2001 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-11391244

RESUMEN

Patients with inborn errors of metabolism undergo liver transplantation, but the effect of transplanting the liver of healthy carriers of these conditions has not been fully clarified. A 6-year-old girl with classical citrullinemia, who repeatedly suffered from hyperammonemia, underwent living-related liver transplantation by using a segment of the liver of her mother, who was a heterozygote carrier for classical citrullinemia. Hyperammonemia alleviated in the patient after the transplantation, thereby dramatically improving her quality of life. Although the levels of plasma and urinary citrulline remained high postoperatively, there was no marked difference in the level of plasma citrulline up to 1 month after surgery when compared with that of previously reported orthotopic liver transplantation cases with classical citrullinemia.


Asunto(s)
Citrulinemia/cirugía , Trasplante de Hígado , Donadores Vivos , Niño , Citrulina/sangre , Citrulina/orina , Citrulinemia/sangre , Citrulinemia/orina , Femenino , Humanos , Hiperamonemia/sangre , Periodo Posoperatorio , Calidad de Vida
15.
Biochem Eng J ; 8(1): 39-43, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11356369

RESUMEN

As part of a research program aimed at producing biodiesel fuel from plant oils enzymatically cells of Rhizopus oryzae (R. oryzae) IFO4697 (with a 1,3-positional specificity lipase) immobilized within biomass support particles (BSPs) were investigated for the methanolysis of soybean oil. The R. oryzae cells easily became immobilized within the BSPs during batch operation. To enhance the methanolysis activity of the immobilized cells under the culture conditions used, various substrate-related compounds were added to the culture medium. Among the compounds tested, olive oil or oleic acid was significantly effective. In contrast, no glucose was necessary. Immobilized cells were treated with several organic solvents, but none gave higher activity than untreated cells. When methanolysis was carried out with stepwise additions of methanol using BSP-immobilized cells, in the presence of 15% water the methyl esters (MEs) content in the reaction mixture reached 90% - the same level as that using the extracellular lipase. The process presented here, using a whole cell biocatalyst, is considered to be promising for biodiesel fuel production in industrial applications.

16.
Anal Sci ; 17(1): 113-7, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11993646

RESUMEN

A molecular-dynamics simulation method has been applied to investigate the influence of the mobile-phase composition on the retention of solutes in HPLC. The distribution profiles of the distance between two atoms in ODS ligands were constructed to characterize the conformation of ODS ligand molecules. The distinct difference of ODS conformation is observed by comparing molecular models consisting of solvent molecules at each solvent composition. The distribution profiles of the distance between the mobile-phase solvent molecules and ODS ligand molecules were also constructed to characterize the distribution of the solvent molecules at each composition. In all distribution profiles, the difference in the distribution due to a change in the solvent compositions was very clearly found, and the facts seem to be very reasonable. The distribution profiles of the distance between the solute, n-propylbenzene, and the terminal carbon atom in the ODS ligand, and between the solute and the silicon atom in the ODS ligand have been also constructed to see the distribution of the solutes in the separation system. The calculated solute distribution in the ODS-methanol/water system is very consistent with the actual chromatographic retention behaviors.

17.
Am J Physiol Heart Circ Physiol ; 279(3): H1392-6, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10993807

RESUMEN

We examined whether transmyocardial revascularization (TMR) relieves myocardial ischemia by increasing regional perfusion via the transmural channels in acute canine experiments. Regional blood flow during transient coronary ligation (2 min) was compared before and 30 min after TMR, and at the third transient ischemia the mid-left ventricle (LV) was cut and immediately frozen along the short axis for the analysis of NADH fluorescence in the regions around the TMR channels. In low-resolution analysis (2-4 g tissue or 2-3 cm(2) area), regional perfusion was not significantly altered after TMR, and NADH fluorescence was observed throughout the ischemic region without significant spatial variation. High-resolution analysis (2.8 mg, 1 mm x 1 mm) revealed that the flow after TMR was lower, and NADH fluorescence was higher in the regions close to the channels (1-2 mm) than in the regions 3-4 mm away from them. Creating TMR channels did not improve the regional perfusion and rather aggravated the local ischemia in the vicinity of the channels in the immediate phase.


Asunto(s)
Circulación Coronaria , Terapia por Láser/efectos adversos , Isquemia Miocárdica/cirugía , Revascularización Miocárdica/efectos adversos , Análisis de Varianza , Animales , Velocidad del Flujo Sanguíneo , Modelos Animales de Enfermedad , Perros , Microesferas , Isquemia Miocárdica/metabolismo , Revascularización Miocárdica/métodos , Miocardio/química , Miocardio/metabolismo , Miocardio/patología , NAD/análisis , NAD/metabolismo , Periodo Posoperatorio , Análisis de Regresión , Espectrometría por Rayos X
18.
Intern Med ; 39(8): 612-7, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10939533

RESUMEN

OBJECTIVE: The quantitative gated SPECT (QGS) software is able to calculate LV volumes and visualize LV wall motion and perfusion throughout the cardiac cycle using an automatic edge detection algorithm of the left ventricle. We evaluated the reliability of global and regional LV function assessment derived from QGS by comparing it with the results from left ventriculo-cineangiography (LVG). PATIENTS: In 20 patients with left ventricular dysfunction who underwent ECG gated 99mTc-tetrofosmin SPECT, the end-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (LVEF) were calculated. The QGS-assessed regional wall motion was determined using the cinematic display. RESULTS: QGS-derived EDV, ESV and LVEF correlated well with those by LVG (p<0.001 for each). There was a good correlation between wall motion score (WMS) derived from the QGS and the LVG (r=0.40, p<0.05). In some patients with extensive myocardial infarction, there was a discrepancy in the regional wall motion results between QGS and LVG. CONCLUSIONS: The ECG-gated SPECT using QGS is useful to evaluate global and regional LV functions in left ventricular dysfunction.


Asunto(s)
Compuestos Organofosforados , Compuestos de Organotecnecio , Radiofármacos , Tomografía Computarizada de Emisión de Fotón Único/métodos , Disfunción Ventricular Izquierda/diagnóstico por imagen , Función Ventricular Izquierda , Adulto , Anciano , Algoritmos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada de Emisión de Fotón Único/estadística & datos numéricos , Disfunción Ventricular Izquierda/fisiopatología
19.
Gene ; 251(1): 73-80, 2000 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-10863098

RESUMEN

Infection with hepadnaviruses and exposure to aflatoxin B1 (AFB1) are considered to be major risk factors in the development of hepatocellular carcinoma (HCC) in humans. A high rate of p53 mutations at codon 249 has been reported in these tumors. The tree shrew (Tupaia belangeri chinensis) is a useful animal model for the development of HCC after human hepatitis B virus (HBV) infection or AFB1 treatment. Therefore, it was of particular interest to determine whether the p53 gene in tree shrew HCCs associated with HBV infection and/or with exposure to AFB1 is affected in the same manner as in human HCCs. We determined the tree shrew p53 wild-type nucleotide sequences by RT-PCR and automatic DNA-sequencing. Tree shrew wild-type p53 sequence showed 91.7 and 93.4% homologies with human p53 nucleotide and amino acids sequences, respectively, while it showed 77.2 and 73.7% homologies in mice. One HCC and normal liver tissue from AFB1 treated and one HCC from AFB1- and HBV-treated tree shrew showed no change in p53 sequences, while three HCCs from AFB1- and HBV-treated tree shrews showed point mutations in p53 sequences. One HCC showed point mutations at codon 275, which is on the DNA-binding domain of p53 gene, which might be a cause of gain-of-function during the development of HCC. As a result, our finding indicates that tree shrews exposed to AFB1 and/or HBV had neither codon 249 mutations nor significant levels of other mutations in the p53 gene, as is the case with humans.


Asunto(s)
Aflatoxina B1/toxicidad , Carcinoma Hepatocelular/genética , Hepatitis B/virología , Neoplasias Hepáticas/genética , Proteína p53 Supresora de Tumor/genética , Tupaiidae/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Carcinoma Hepatocelular/inducido químicamente , Carcinoma Hepatocelular/virología , Clonación Molecular , Análisis Mutacional de ADN , ADN Complementario/química , ADN Complementario/genética , Modelos Animales de Enfermedad , Genes Supresores de Tumor/genética , Virus de la Hepatitis B , Hígado/metabolismo , Hígado/patología , Neoplasias Hepáticas/inducido químicamente , Neoplasias Hepáticas/virología , Datos de Secuencia Molecular , Mutación , Mutación Puntual , Alineación de Secuencia , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Homología de Secuencia de Ácido Nucleico
20.
J Biol Chem ; 275(4): 2859-68, 2000 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-10644753

RESUMEN

We previously cloned heparan sulfate 6-O-sulfotransferase (HS6ST) (Habuchi, H., Kobayashi, M., and Kimata, K. (1998) J. Biol. Chem. 273, 9208-9213). In this study, we report the cloning and characterization of three mouse isoforms of HS6ST, a mouse homologue to the original human HS6ST (HS6ST-1) and two novel HS6STs (HS6ST-2 and HS6ST-3). The cDNAs have been obtained from mouse brain cDNA library by cross-hybridization with human HS6ST cDNA. The three cDNAs contained single open reading frames that predicted type II transmembrane proteins composed of 401, 506, and 470 amino acid residues, respectively. Amino acid sequence of HS6ST-1 was 51 and 57% identical to those of HS6ST-2 and HS6ST-3, respectively. HS6ST-2 and HS6ST-3 had the 50% identity. Overexpression of each isoform in COS-7 cells resulted in about 10-fold increase of HS6ST activity. The three isoforms purified with anti-FLAG antibody affinity column transferred sulfate to heparan sulfate and heparin but not to other glycosaminoglycans. Each isoform showed different specificity toward the isomeric hexuronic acid adjacent to the targeted N-sulfoglucosamine; HS6ST-1 appeared to prefer the iduronosyl N-sulfoglucosamine while HS6ST-2 had a different preference, depending upon the substrate concentrations, and HS6ST-3 acted on either substrate. Northern analysis showed that the expression of each message in various tissues was characteristic to the respective isoform. HS6ST-1 was expressed strongly in liver, and HS6ST-2 was expressed mainly in brain and spleen. In contrast, HS6ST-3 was expressed rather ubiquitously. These results suggest that the expression of these isoforms may be regulated in tissue-specific manners and that each isoform may be involved in the synthesis of heparan sulfates with tissue-specific structures and functions.


Asunto(s)
Heparitina Sulfato/metabolismo , Ácidos Hexurónicos/metabolismo , Isoenzimas/metabolismo , Sulfotransferasas/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Células COS , Clonación Molecular , ADN Complementario , Ácidos Hexurónicos/química , Humanos , Isoenzimas/genética , Ratones , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido , Especificidad por Sustrato , Sulfotransferasas/genética
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