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1.
Acta Biomater ; 175: 55-75, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38141934

RESUMEN

With the lack of minimally invasive tools for probing neuronal systems across spatiotemporal scales, understanding the working mechanism of the nervous system and limited assessments available are imperative to prevent or treat neurological disorders. In particular, nanoengineered neural interfaces can provide a solution to this technological barrier. This review covers recent surface engineering approaches, including nanoscale surface coatings, and a range of topographies from the microscale to the nanoscale, primarily focusing on neural-interfaced biosystems. Specifically, the immobilization of bioactive molecules to fertilize the neural cell lineage, topographical engineering to induce mechanotransduction in neural cells, and enhanced cell-chip coupling using three-dimensional structured surfaces are highlighted. Advances in neural interface design will help us understand the nervous system, thereby achieving the effective treatments for neurological disorders. STATEMENT OF SIGNIFICANCE: • This review focuses on designing bioactive neural interface with a nanoscale chemical modification and topographical engineering at multiscale perspective. • Versatile nanoscale surface coatings and topographies for neural interface are summarized. • Recent advances in bioactive materials applicable for neural cell culture, electrophysiological sensing, and neural implants are reviewed.


Asunto(s)
Mecanotransducción Celular , Enfermedades del Sistema Nervioso , Humanos , Neuronas , Propiedades de Superficie
2.
Anal Chem ; 95(38): 14357-14364, 2023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37712516

RESUMEN

The ongoing coronavirus disease 2019 (COVID-19) pandemic demands rapid and straightforward diagnostic tools to prevent early-stage viral transmission. Although nasopharyngeal swabs are a widely used patient sample collection method for diagnosing COVID-19, using these samples for diagnosis without RNA extraction increases the risk of obtaining false-positive and -negative results. Thus, multiple purification steps are necessary, which are time-consuming, generate significant waste, and result in substantial sample loss. To address these issues, we developed surface-modified polymerase chain reaction (PCR) tubes using the tertiary aminated polymer poly(2-dimethylaminomethylstyrene) (pDMAMS) via initiated chemical vapor deposition. Introducing the clinical samples into the pDMAMS-coated tubes resulted in approximately 100% RNA capture efficiency within 25 min, which occurred through electrostatic interactions between the positively charged pDMAMS surface and the negatively charged RNA. The captured RNA is then detected via chamber digital PCR, enabling a sensitive, accurate, and rapid diagnosis. Our platform provides a simple and efficient RNA extraction and detection strategy that allows detection from 22 nasopharyngeal swabs and 21 saliva specimens with 0% false negatives. The proposed method can facilitate the diagnosis of COVID-19 and contribute to the prevention of early-stage transmission.


Asunto(s)
COVID-19 , Humanos , COVID-19/diagnóstico , Prueba de COVID-19 , Reacción en Cadena de la Polimerasa , Polímeros , ARN
3.
Medicine (Baltimore) ; 101(45): e31431, 2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36397407

RESUMEN

This study aimed to investigate the long-term clinical efficacy of and satisfaction with integrative Korean medicine (KM) treatment in patients with shoulder osteoarthritis (SOA). We conducted a prospective observational study of patients with SOA. Patients aged 19 years and older who underwent inpatient treatment for more than 1 week were eligible for enrollment in the study. The primary evaluation index was the numeric rating scale for shoulder pain. Sub-evaluation indices included the Shoulder Pain and Disability Index for shoulder function, EuroQol-5-dimension score for overall quality of life, and Patient Global Impression of Change. Outcome measures were assessed at admission, discharge, and follow-up. For the follow-up questionnaire survey, the following information was collected: current status, surgery after discharge, reasons for finding integrative KM treatment satisfactory/unsatisfactory, and quality of life after discharge. In total, 186 patients were enrolled in the primary analysis, and 103 patients completed the follow-up survey. The mean number of days of follow-up was 1019 ±â€…439. Compared with the baseline, the mean differences in the numeric rating scale and Shoulder Pain and Disability Index were 3.05 ±â€…0.34 and 36.06 ±â€…5.53, respectively. Regarding the Patient Global Impression of Change, 89 out of 103 (86.4%) patients chose "minimally improved" or better. Furthermore, the EuroQol-5-dimension score also increased, showing an improvement of health-related quality of life after treatment. Integrative KM treatment is a potential option for reducing pain severity and improving function and health-related quality of life in patients with SOA. Prospective randomized studies would support this finding for the next step.


Asunto(s)
Pacientes Internos , Osteoartritis , Humanos , Estudios de Seguimiento , Calidad de Vida , Estudios Prospectivos , Dolor de Hombro/terapia , Hombro , Osteoartritis/terapia , República de Corea
4.
Biomater Res ; 26(1): 35, 2022 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-35869562

RESUMEN

BACKGROUND: Pancreatic cancer, one of the cancers with the highest mortality rate, has very limited clinical treatment. Cancer cells express abnormal glycans on the surface, and some lectins with a high affinity for the glycans induce apoptosis in cancer. In this study, the efficacy of Aleuria Aurantia lectin (AAL) for the treatment of pancreatic cancer was evaluated and the efficacy improvement through AAL delivery with mPEGylated coacervate (mPEG-Coa) was investigated. METHODS: AAL was treated with pancreatic cancer cells, PANC-1, and the expression level of caspase-3 and subsequent apoptosis was analyzed. In particular, the anticancer efficacy of AAL was compared with that of concanavalin A, one of the representative anticancer lectins. Then, methoxypolyethylene glycol-poly(ethylene arginylaspartate diglyceride), a polycation, was synthesized, and an mPEG-Coa complex was prepared with polyanion heparin. The AAL was incorporated into the mPEG-Coa and the release kinetics of the AAL from the mPEG-Coa and the cargo protection capacity of the mPEG-Coa were evaluated. Finally, improved anticancer ability through Coa-mediated AAL delivery was assessed. RESULTS: These results indicated that AAL is a potential effective pancreatic cancer treatment. Moreover, mPEG-Coa rapidly released AAL at pH 6.5, an acidic condition in the cancer microenvironment. The initial rapid release of AAL effectively suppressed pancreatic cancer cells, and the continuous supply of AAL through the Coa transporter effectively inhibited proliferation recurrence of cancer cells. CONCLUSION: AAL is a potential novel drug for the treatment of pancreatic cancer therapeutic agent. In addition, a continuous supply of drugs above the therapeutic threshold using mPEG-Coa could improve therapeutic efficacy.

5.
PLoS One ; 17(2): e0264272, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35213617

RESUMEN

BACKGROUND: The purpose of a rapid response system (RRS) is to reduce the incidence of preventable cardiopulmonary arrests (CPAs) and patient deterioration in general wards. The objective of this study is to investigate the incidence and temporal trends of preventable CPAs and determine factors associated with preventable CPAs in a hospital with a mature RRS. METHODS: This was a single-center prospective cohort study of all CPAs occurring in the general ward between March 2017 and June 2020. The RRS operates from 07:00 to 23:00 on weekdays and from 07:00 to 12:00 on Saturdays. All CPAs were reviewed upon biweekly conference, and a panel of intensivists judged their preventability. Trends of preventable CPAs were analyzed using Poisson regression models and factors associated with preventable CPAs were analyzed using multivariable logistic regression. RESULTS: There were 253 CPAs over 40 months, and 64 (25.3%) of these were preventable. The incidence rate of CPAs was 1.07 per 1000 admissions and that of preventable CPAs was 0.27 per 1000 admissions. The number of preventable CPAs decreased by 24% each year (incidence rate ratio = 0.76; p = 0.039) without a change in the total CPA incidence. The most common contributor to the preventability was delayed response from physicians (n = 41, 64.1%). A predictable CPA with a pre-alarm sign had increased odds in the occurrence of preventable CPAs, while a cardiac cause of CPAs and RRS operating hours had decreased odds in terms of occurrence of preventable CPA. CONCLUSION: Our study showed that one-fourth of all CPAs occurring in the general wards were preventable, and these arrests decreased each year. A mature RRS can evolve to reduce preventable CPAs with regular self-evaluation. Efforts should be directed at improving physicians' response time since a delay in their response was the most common cause of preventable CPAs.


Asunto(s)
Paro Cardíaco/mortalidad , Mortalidad Hospitalaria , Anciano , Anciano de 80 o más Años , Femenino , Paro Cardíaco/prevención & control , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Tiempo
6.
Tissue Eng Regen Med ; 19(2): 309-319, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34905183

RESUMEN

BACKGROUND: The development of three-dimensional hydrogels using polymeric biomaterials is a key technology for tissue engineering and regenerative medicine. Successful tissue engineering requires the control and identification of the physicochemical properties of hydrogels. METHODS: Interpenetrating network (IPN) hydrogel was developed using thiolated gelatin (GSH) and poly(ethylene glycol) diacrylate (PEGDA), with the aid of ammonium persulfate (APS) and N,N,N,N'-tetramethylethylenediamine (TEMED) as radical initiators. Each component was prepared in the following concentrations, respectively: 2.5 and 5% GSH (LG and HG), 12.5 and 25% PEGDA (LP and HP), 3% APS/1.5% TEMED (LI), and 4% APS/2% TEMED (HI). IPN hydrogel was fabricated by the mixing of GSH, PEGDA, and initiators in 5:4:1 volume ratios, and incubated at 37 °C for 30 min in the following 6 experimental formulations: (1) HG-LP-LI, (2) HG-LP-HI, (3) LG-HP-LI, (4) LG-HP-HI, (5) HG-HP-HI, and (6) HG-HP-LI. Herein, the physico-chemical characteristics of IPN hydrogels, including their morphological structures, hydrolytic degradation properties, mechanical properties, embedded protein release kinetics, and biocompatibility, were investigated. RESULTS: The characteristics of the hydrogel were significantly manipulated by the concentration of the polymer, especially the conversion between HP and LP, rather than the concentration of the initiator, and no hydrogel formulation exhibited any toxicity to fibroblast and HaCaT cells. CONCLUSION: We provide structural-physical relationships of the hydrogels by which means their physical properties could be conveniently controlled through component control, which could be versatilely utilized for various organizational engineering strategies.


Asunto(s)
Gelatina , Hidrogeles , Fibroblastos , Gelatina/química , Hidrogeles/química , Polietilenglicoles/química , Ingeniería de Tejidos
7.
Intell Serv Robot ; 14(5): 729-739, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34804242

RESUMEN

This study aims to analyze the concept of companion robots for older adults from the perspective of nursing. This study employed a concept analysis. The literature from July 2011 to June 2021 was sought from databases using specific keywords. Any quantitative or qualitative study published in English or Korean focusing on companion robots for older adults was included in the study. Rodgers' evolutionary concept analysis was used to clarify the antecedents, attributes, and consequences. Seventy-five eligible articles were studied. The findings were categorized into antecedents, attributes, and consequences. Companion robot antecedents were classified into individual factors, attitude toward robots, and caregiver and social factors. The defining attributes included human-robot interaction, function, features, structure, cost, and management of the robot being a companion. Consequences were categorized into user, caregiver, and health related. Companion robots are designed to enhance well-being, quality of life, and independence by providing service and companionship and assisting daily life. This mainly includes cognitive and social support, mobility support, relaxation, health monitoring, and self-care support through human-robot interaction. The attributes, antecedents, and consequences of companion robots identified in this study can inform future decision making and interventions by caregivers for aging in place.

8.
Pharmaceutics ; 13(9)2021 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-34575449

RESUMEN

As a currently spotlighted method for cancer treatment, cancer immunotherapy has made a lot of progress in recent years. Among tremendous cancer immunotherapy boosters available nowadays, Toll-like receptor (TLR) agonists were specifically selected, because of their effective activation of innate and adaptive immune cells, such as dendritic cells (DCs), T cells, and macrophages. TLR agonists can activate signaling pathways of DCs to express CD80 and CD86 molecules, and secrete various cytokines and chemokines. The maturation of DCs stimulates naïve T cells to differentiate into functional cells, and induces B cell activation. Although TLR agonists have anti-tumor ability by activating the immune system of the host, their drawbacks, which include poor efficiency and remarkably short retention time in the body, must be overcome. In this review, we classify and summarize the recently reported delivery strategies using (1) exogenous TLR agonists to maintain the biological and physiological signaling activities of cargo agonists, (2) usage of multiple TLR agonists for synergistic immune responses, and (3) co-delivery using the combination with other immunomodulators or stimulants. In contrast to naked TLR agonists, these exogenous TLR delivery strategies successfully facilitated immune responses and subsequently mediated anti-tumor efficacy.

9.
PLoS One ; 14(11): e0225229, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31725773

RESUMEN

BACKGROUND: Although scoring and machine learning methods have been developed to predict patient deterioration, bedside assessment by nurses should not be overlooked. This study aimed to evaluate the performance of subjective bedside assessment of the patient by the rapid response team (RRT) nurses in predicting short-term patient deterioration. METHODS: Patients noticed by RRT nurses based on the vital sign instability, abnormal laboratory results, and direct contact via phone between November 1, 2016, and December 12, 2017, were included. Five RRT nurses visited the patients according to their shifts and assessed the possibility of patient deterioration. Patient acuity rating (PAR), a scale of 1-7, was used as the tool of bedside assessment. Other scores, including the modified early warning score, VitalPAC early warning score, standardised early warning score, and cardiac arrest risk triage, were calculated afterwards. The performance of these scores in predicting mortality and/or intensive care unit admission within 1 day was compared by calculating the area under the receiver operating curve. RESULTS: A total of 1,426 patients were included in the study, of which 258 (18.1%) died or were admitted to the intensive care unit within 1 day. The area under the receiver operating curve of PAR was 0.87 (95% confidence interval [CI] 0.84-0.89), which was higher than those of modified early warning score (0.66, 95% CI 0.62-0.70), VitalPAC early warning score (0.69, 95% CI 0.66-0.73), standardised early warning score (0.67, 95% CI 0.63-0.70) and cardiac arrest risk triage (0.63, 95% CI 0.59-0.66) (P<0.001). CONCLUSIONS: PAR assessed by RRT nurses can be a useful tool for assessing short-term patient prognosis in the RRT setting.


Asunto(s)
Equipo Hospitalario de Respuesta Rápida , Enfermeras y Enfermeros , Gravedad del Paciente , Anciano , Anciano de 80 o más Años , Cuidados Críticos , Femenino , Humanos , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Pronóstico , Curva ROC
10.
J Transl Med ; 15(1): 16, 2017 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-28109298

RESUMEN

OBJECTIVE: We performed a randomized, double-blind, cross-over study to assess the neuroregenerative potential of intravenous granulocyte colony-stimulating factor (G-CSF) followed by infusion of mobilized peripheral blood mononuclear cells (mPBMCs) in children with cerebral palsy (CP). METHODS: Children with non-severe CP were enrolled in this study. G-CSF was administered for 5 days, then mPBMCs were collected by apheresis and cryopreserved. One month later (M1), recipients were randomized to receive either mPBMCs or a placebo infusion, and these treatment groups were switched at 7 months (M7) and observed for another 6 months (M13). We assessed the efficacy of treatment by evaluating neurodevelopmental tests, as well as by brain magnetic resonance imaging-diffusion tensor imaging (MRI-DTI) and 18F-fluorodeoxyglucose (FDG) brain positron emission tomography-computed tomography (PET-CT) scanning to evaluate the anatomical and functional changes in the brain. RESULTS: Fifty-seven patients aged 4.3 ± 1.9 (range 2-10) years and weighing 16.6 ± 4.9 (range 11.6-56.0) kg were enrolled in this study. The administration of G-CSF as well as the collection and reinfusion of mPBMCs were safe and tolerable. The yield of mPBMCs was comparable to that reported in studies of pediatric donors without CP and patients with nonhematologic diseases. 42.6% of the patients responded to the treatment with higher neurodevelopmental scores than would normally be expected. In addition, larger changes in neurodevelopment test scores were observed in the 1 month after G-CSF administration (M0-M1) than during the 6 months after reinfusion with mPBMCs or placebo (M1-M7 or M7-M13). Patients who received G-CSF followed by mPBMC infusion at 7 months (T7 group) demonstrated significantly more neurodevelopmental improvement than patients who received G-CSF followed by mPBMC infusion at 1 month (T1 group). In contrast to the results of neurodevelopment tests, the results of MRI-DTI at the end of this study showed greater improvement in the T1 group. Although we observed metabolic changes to the cerebellum, thalamus and cerebral cortex in the 18F-FDG brain PET-CT scans, there were no significant differences in such changes between the mPBMC and placebo group or between the T1 and T7 group. CONCLUSIONS: Neurodevelopmental improvement was seen in response to intravenous G-CSF followed by mPBMC reinfusion, particularly to the G-CSF alone even without mPBMC reinfusion. Further studies using a larger number of mPBMCs for the infusion which could be collected by repeated cycles of apheresis or using repeated cycles of G-CSF alone, are needed to clarify the effect of mPBMC reinfusion or G-CSF alone (Trial registration: ClinicalTrials.gov, NCT02983708. Registered 5 December, 2016, retrospectively registered).


Asunto(s)
Parálisis Cerebral/terapia , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Regeneración Nerviosa , Trasplante de Células Madre de Sangre Periférica , Células Madre de Sangre Periférica/citología , Anisotropía , Encéfalo/patología , Recuento de Células , Parálisis Cerebral/tratamiento farmacológico , Parálisis Cerebral/fisiopatología , Niño , Preescolar , Estudios Cruzados , Criopreservación , Demografía , Método Doble Ciego , Factor Estimulante de Colonias de Granulocitos/farmacología , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Humanos , Inyecciones Intravenosas , Imagen por Resonancia Magnética , Regeneración Nerviosa/efectos de los fármacos , Pruebas Neuropsicológicas , Padres , Células Madre de Sangre Periférica/efectos de los fármacos , Tomografía Computarizada por Tomografía de Emisión de Positrones , Recuperación de la Función/efectos de los fármacos , Trasplante Autólogo , Resultado del Tratamiento
11.
Reprod Toxicol ; 69: 43-52, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28111094

RESUMEN

Chronic caffeine consumption exerts a negligible effect on the reproductive organs of normal adult females, but it is not known whether this is also true for children and adolescents. Here, we investigated the effects of high caffeine exposure on sexual maturation and ovarian estradiol production in immature female rats. Immature female SD rats were divided into controls and caffeine groups fed 120 and 180mg/kg/day for 4 or 8 weeks. There was a significant delay in vaginal opening in the caffeine-fed groups. In addition, serum estradiol levels were elevated in the caffeine-fed animals after 2 and 4 weeks of exposure. Estradiol secretion as well as aromatase expression also increased significantly in the ovarian cells in response to caffeine. These results demonstrate that peripubertal exposure to high caffeine increases estradiol production in the ovary; this may disturb the coordinated regulation of the hypothalamo-pituitary-ovarian axis, thereby interfering with sexual maturation.


Asunto(s)
Cafeína/toxicidad , Estradiol/metabolismo , Ovario/efectos de los fármacos , Tejido Adiposo/efectos de los fármacos , Animales , Aromatasa/metabolismo , Peso Corporal/efectos de los fármacos , Estradiol/sangre , Femenino , Ovario/crecimiento & desarrollo , Ovario/metabolismo , Ratas Sprague-Dawley , Maduración Sexual/efectos de los fármacos , Útero/efectos de los fármacos , Útero/crecimiento & desarrollo
12.
J Med Food ; 19(1): 73-84, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26495862

RESUMEN

This study investigated the dose- and time-dependent effects of caffeine consumption throughout puberty in peripubertal rats. A total of 85 male SD rats were randomly divided into four groups: control and caffeine-fed groups with 20, 60, or 120 mg/kg/day through oral gavage for 10, 20, 30, or 40 days. Caffeine decreased body weight gain and food consumption in a dose- and time-dependent manner, accompanied by a reduction in muscle and body fat. In addition, it caused a shortening and lightening of leg bones and spinal column. The total height of the growth plate decreased sharply at 40 days in the controls, but not in the caffeine-fed groups, and the height of hypertrophic zone in the caffeine-fed groups was lower than in the control. Caffeine increased the height of the secondary spongiosa, whereas parameters related to bone formation, such as bone area ratio, thickness and number of trabeculae, and bone perimeter, were significantly reduced. Furthermore, serum levels of IGF-1, estradiol, and testosterone were also reduced by the dose of caffeine exposure. Our results demonstrate that caffeine consumption can dose- and time-dependently inhibit longitudinal bone growth in immature male rats, possibly by blocking the physiologic changes in body composition and hormones relevant to bone growth.


Asunto(s)
Desarrollo Óseo/efectos de los fármacos , Cafeína/efectos adversos , Pubertad/efectos de los fármacos , Animales , Peso Corporal/efectos de los fármacos , Densidad Ósea/efectos de los fármacos , Placa de Crecimiento/crecimiento & desarrollo , Placa de Crecimiento/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Pubertad/fisiología , Ratas , Ratas Sprague-Dawley , Testosterona/metabolismo
13.
J Anat ; 227(1): 10-20, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26041429

RESUMEN

Caffeine adversely affects endochondral ossification during fetal skeletal growth, and results in increased incidence of delayed and abnormal fetal skeletal development. Chronic caffeine intake also decreases growth hormone secretion. Thus, it is conceivable that caffeine may disrupt bone growth during the peripubertal period. This study aimed to investigate the impact of high-caffeine consumption on bone growth throughout puberty. A total of 51 male rats (21 days old) were divided randomly into three groups: a control group and two groups fed caffeine via gavage with 120 and 180 mg kg(-1)  day(-1) for 4 weeks. After death, the final length and weight of leg bones were measured, and the tibia processed for histomorphometric analysis. Caffeine caused a significant decrease in body mass gain. This was accompanied with proportional decreases in lean body mass and body fat. In addition, bone mass and osteogenic activity in vivo were assessed using dual-energy X-ray absorptiometry and (18) F-NaF positron emission tomography. The results showed significant decreases of bone mass and in vivo osteogenic activity in the caffeine-fed groups. Rats fed with caffeine showed a significantly shorter and lighter tibia and femur and the vertebral column compared with controls. In addition, caffeine does not increase the width of the growth plates (GPs), it slows the rate at which the GP closes due to a slower rate of growth. These results demonstrated that caffeine altered osteogenic activity, leading to delayed peripubertal longitudinal bone growth and maturation. Given that osteogenic cells undergo dynamic changes in metabolic activity and that the pubertal growth spurt is mainly stimulated by growth hormone/insulin-like growth factor-1 and sex steroids during pubertal development, caffeine could suppress ossification by interfering with both physiological changes in hormonal secretion and osteogenic activity during this critical period. Further study will be needed to investigate the cellular/molecular mechanism by which caffeine affects osteogenesis using in vitro experimental models.


Asunto(s)
Desarrollo Óseo/efectos de los fármacos , Cafeína/efectos adversos , Estimulantes del Sistema Nervioso Central/efectos adversos , Absorciometría de Fotón , Animales , Peso Corporal/efectos de los fármacos , Densidad Ósea/efectos de los fármacos , Cafeína/administración & dosificación , Estimulantes del Sistema Nervioso Central/administración & dosificación , Modelos Animales de Enfermedad , Fémur/efectos de los fármacos , Placa de Crecimiento/efectos de los fármacos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Osteogénesis/efectos de los fármacos , Tomografía de Emisión de Positrones , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Tibia/efectos de los fármacos
14.
World J Gastroenterol ; 20(1): 228-34, 2014 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-24415876

RESUMEN

AIM: To investigate the usefulness of a novel thallium scan shunt index for assessing portosystemic shunt-related cirrhotic complications. METHODS: We enrolled 209 chronic hepatitis B-related cirrhosis patients. After rectal thallium instillation, radioactive isotope activity in the heart and liver was measured. The ratio of radiation uptake between the heart and the liver was calculated (the shunt index). This value indicates the degree of portosystemic circulation shunting. Blood tests, serum biochemistry tests, abdominal ultrasonography, gastroscopy and examination of clinical features such as the occurrence of varices, bleeding and hepatic encephalopathy were performed. Multivariate analysis was used to identify independent risk factors for complications. We compared the cumulative incidence rates of complications during the follow-up period. RESULTS: The thallium scan shunt index was significantly higher in the decompensated liver cirrhosis group than in the compensated liver cirrhosis group (0.91 ± 0.39 vs 0.39 ± 0.32, P < 0.001). It was also higher in the varices group, the hepatic encephalopathy group, and the variceal bleeding group than in the control group (P < 0.001). Multivariate analysis showed that the index was an independent risk factor for predicting decompensated liver cirrhosis. When the cut-off value was 0.75, the shunt index had a sensitivity of 82.6%, a specificity of 84%, a positive predictive value of 61.5%, and a negative predictive value of 94.4% in diagnosing decompensated cirrhosis. When the shunt index was greater than 0.75, there was a significant increase in the number of decompensated events. CONCLUSION: The thallium shunt index is a good predictor of cirrhosis-related complications.


Asunto(s)
Várices Esofágicas y Gástricas/diagnóstico por imagen , Hemorragia Gastrointestinal/diagnóstico por imagen , Corazón/diagnóstico por imagen , Encefalopatía Hepática/diagnóstico por imagen , Hepatitis B Crónica/complicaciones , Hipertensión Portal/diagnóstico por imagen , Cirrosis Hepática/diagnóstico por imagen , Hígado/diagnóstico por imagen , Radiofármacos , Radioisótopos de Talio , Várices Esofágicas y Gástricas/fisiopatología , Várices Esofágicas y Gástricas/virología , Hemorragia Gastrointestinal/fisiopatología , Hemorragia Gastrointestinal/virología , Encefalopatía Hepática/fisiopatología , Encefalopatía Hepática/virología , Humanos , Hipertensión Portal/fisiopatología , Hipertensión Portal/virología , Incidencia , Estimación de Kaplan-Meier , Cirrosis Hepática/fisiopatología , Cirrosis Hepática/virología , Modelos Logísticos , Análisis Multivariante , Valor Predictivo de las Pruebas , Pronóstico , Cintigrafía , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo
15.
Malar J ; 12: 47, 2013 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-23374507

RESUMEN

BACKGROUND: With the increasing resistance of malaria parasites to available drugs, there is an urgent demand to develop new anti-malarial drugs. Calpain inhibitor, ALLN, is proposed to inhibit parasite proliferation by suppressing haemoglobin degradation. This provides Plasmodium calpain as a potential target for drug development. Pf-calpain, a cysteine protease of Plasmodium falciparum, belongs to calpain-7 family, which is an atypical calpain not harboring Ca2+-binding regulatory motifs. In this present study, in order to establish the screening system for Pf-calpain specific inhibitors, the active form of Pf-calpain was first identified. METHODS: Recombinant Pf-calpain including catalytic subdomain IIa (rPfcal-IIa) was heterologously expressed and purified. Enzymatic activity was determined by both fluorogenic substrate assay and gelatin zymography. Molecular homology modeling was carried out to address the activation mode of Pf-calpain in the aspect of structural moiety. RESULTS: Based on the measurement of enzymatic activity and protease inhibitor assay, it was found that the active form of Pf-calpain only contains the catalytic subdomain IIa, suggesting that Pf-calpain may function as a monomeric form. The sequence prediction indicates that the catalytic subdomain IIa contains all amino acid residues necessary for catalytic triad (Cys-His-Asn) formation. Molecular modeling suggests that the Pf-calpain subdomain IIa makes an active site, holding the catalytic triad residues in their appropriate orientation for catalysis. The mutation analysis further supports that those amino acid residues are functional and have enzymatic activity. CONCLUSION: The identified active form of Pf-calpain could be utilized to establish high-throughput screening system for Pf-calpain inhibitors. Due to its unique monomeric structural property, Pf-calpain could be served as a novel anti-malarial drug target, which has a high specificity for malaria parasite. In addition, the monomeric form of enzyme may contribute to relatively simple synthesis of selective inhibitors.


Asunto(s)
Antimaláricos/farmacología , Calpaína/antagonistas & inhibidores , Evaluación Preclínica de Medicamentos/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , Plasmodium falciparum/efectos de los fármacos , Plasmodium falciparum/enzimología , Secuencia de Aminoácidos , Antimaláricos/aislamiento & purificación , Calpaína/genética , Calpaína/aislamiento & purificación , Modelos Moleculares , Datos de Secuencia Molecular , Conformación Proteica , Proteínas Recombinantes/antagonistas & inhibidores , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Homología de Secuencia de Aminoácido
16.
Clin Nucl Med ; 38(3): 169-74, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23354030

RESUMEN

PURPOSE: The present study aimed to determine the predictive value of the heart-liver uptake ratio (H/L ratio) of rectally administered (201)Tl scintigraphy for hepatic decompensation, which was conducted in 107 patients with cirrhosis. METHODS: We retrospectively assessed the predictive value of a noninvasive parameter, H/L ratio, for decompensation during a median follow-up period of 45.4 months using follow-up data from 1996 through 2008 for 107 patients with compensated cirrhosis. Logistic regression analysis and odds ratio estimates were used to estimate independent value of the H/L ratio on the risk of decompensation with 95% confidence intervals. RESULTS: At first visit, all subjects were confirmed as patients with compensated cirrhosis, 39 by liver biopsy and 68 by standard laboratory and radiological criteria. At end of the evaluation time, 81 patients remained compensated, whereas 26 patients decompensated as evidenced by ascites in 23, hepatic encephalopathy in 8, and variceal bleeding in 1 patient. First-visit parameters except bilirubin level, alanine aminotransferase (ALT), and H/L ratio and last visit parameters except ALT and aspartate aminotransferase-ALT ratio were significantly different between the 2 groups as ascertained by Wilcoxon rank sum test (P < 0.05). Among those parameters, we found that the last visit H/L ratio was a strongly reliable predictor of decompensation with an odds ratio estimates of 14.443, area under the receiver operating characteristic curve of 0.825, cutoff of 0.4, sensitivity of 73.1 %, and specificity of 71.6%. CONCLUSIONS: This evidence indicates that in patients with compensated cirrhosis, an increased H/L ratio at follow-up may be a useful predictive parameter showing a high risk of progression to a decompensated state.


Asunto(s)
Corazón/diagnóstico por imagen , Cirrosis Hepática/complicaciones , Cirrosis Hepática/metabolismo , Hígado/diagnóstico por imagen , Hígado/metabolismo , Radioisótopos de Talio/metabolismo , Adulto , Anciano , Transporte Biológico , Femenino , Humanos , Cirrosis Hepática/diagnóstico por imagen , Modelos Logísticos , Masculino , Persona de Mediana Edad , Cintigrafía , Estudios Retrospectivos
17.
Int J Cardiol ; 143(2): 202-5, 2010 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-19203805

RESUMEN

We hypothesized that delaying the timing of intra-coronary infusion of G-CSF mobilized stem cell until at least 4 weeks after coronary stenting should avoid the stimulation of vascular smooth muscle cells during the early active cellular proliferative phase, thus decreases in-stent restenosis while preserving the beneficial effect of stem cell therapy on cardiac function in patients with myocardial infarction (MI). 25 patients with ST-elevation myocardial infarction (STEMI) treated with stenting were enrolled in this pilot study. The ages of MI at the time of cell treatment were from 1 month to 59 months. At 6 months follow-up, the left ventricular ejection fraction (LVEF) increased from 32% to 37.7% and the stress thallium perfusion defect decreased from 31.4% to 28.1%. Cell treatment-related complications such as arrhythmias were not observed. 9 patients who underwent cell treatment less than 3 months after coronary stenting were evaluated for in-stent restenosis; it was found in only 1 patient. This pilot study shows that delayed more than 4 weeks after coronary stenting but less than 3 months after MI, intra-coronary infusion of G-CSF mobilized PBSCs may improve cardiac function without triggering in-stent restenosis.


Asunto(s)
Reestenosis Coronaria/terapia , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Movilización de Célula Madre Hematopoyética/métodos , Infarto del Miocardio/terapia , Función Ventricular Izquierda/fisiología , Preescolar , Esquema de Medicación , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Stents/efectos adversos
18.
Exp Parasitol ; 124(3): 341-5, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19861123

RESUMEN

Pf-calpain, a cysteine protease of Plasmodium falciparum, is believed to be one of the central mediators for essential parasitic activity. However, the roles of calpain on parasitic activity have not been determined in P. falciparum. In the present study, the localization of Pf-calpain was investigated using polyclonal antibodies (anti-Pf-calpain antibody A and B) against peptides that distinguished it from human calpain-7 and rat calpain-10 protein. Recombinant Pf-calpain (rPf-calpain) was identified as a 46 kDa protein using an anti-Pf-calpain antibody A, which can recognize the Pf-calpain binding site. Confocal microscopy revealed calpain within cytoplasmic localized parasites in the erythrocytic cycle. The findings suggested that the expression of Pf-calpain would be proportional to all different parasites in the erythrocytic cycle. On the other hand, anti-human calpain-7 antibody detected Pf-calpain in schizonts, and the immunofluorescence was stronger than with anti-rat calpain-10 antibody. However, the antibodies reacted with calpains in human red blood cells. These results show that anti-Pf-calpain antibody A and B specifically recognize only Pf-calpain. Taken together, the results suggest that Pf-calpain is expressed in all erythrocytic stages. In particular, the expression of Pf-calpain is increased much more when the late ring matures into the early trophozoite. Moreover, anti-Pf-calpain antibody A and B against synthetic peptides of the catalytic domain of Pf-calpain are useful to specifically detect Pf-calpain in all erythrocytic stages, while human and rat calpain antibody are not useful.


Asunto(s)
Calpaína/análisis , Plasmodium falciparum/enzimología , Secuencia de Aminoácidos , Animales , Western Blotting , Calpaína/química , Calpaína/genética , Calpaína/inmunología , Electroforesis en Gel de Poliacrilamida , Técnica del Anticuerpo Fluorescente , Humanos , Microscopía Confocal , Datos de Secuencia Molecular , Plasmodium falciparum/genética , Ratas , Alineación de Secuencia , Homología de Secuencia de Aminoácido
19.
Arch Pharm Res ; 32(6): 899-906, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19557368

RESUMEN

The biological understanding of malaria parasites has increased considerably over the past two decades with the discovery of many potential targets for the development of new antimalarial drugs. Calpain, a cysteine protease of Plasmodium falciparum, is believed to be a central mediator essential for parasitic activity. However, the utility of calpain as a potential anti-malarial target in P. falciparum has not been fully determined. In the present study, we determined the effect of N-acetyl-L-Leucyl-L-leucyl-L-norleucinal (ALLN)-treatment on the expression of calpain in erythrocytic stages of P. falciparum and its usefulness as an antimalarial chemotherapeutic agent. ALLN was shown to have low toxicity to HeLa cells but high toxicity to malaria. ALLN inhibited the expression of calpain in ring, trophozoite and schizont stages when treated for 48 h. Also, after 48 h, samples were characterized by 6.15% and 0% parasitemia without ALLN treatment and with ALLN treatment, respectively. Brightfield and confocal microscopy revealed that ALLN treatment affects merozoite maturation. As ALLN concentration increased from 1 muM to 100 microM, ring stage parasites did not mature into the schizont stage. When ALLN treatment was continued for 48 h, it also significantly inhibited the maturation of ring-stage parasites into trophozoite or schizont stages and survival of malarial parasites. Taken together, these findings suggest that ALLN inhibit the maturation and survival of P. falciparum and calpain expression, and thus has potential utility as an antimalarial chemotherapeutic agent.


Asunto(s)
Antimaláricos/farmacología , Calpaína/antagonistas & inhibidores , Leupeptinas/farmacología , Plasmodium falciparum/efectos de los fármacos , Proteínas Protozoarias/antagonistas & inhibidores , Animales , Evaluación Preclínica de Medicamentos , Eritrocitos/efectos de los fármacos , Eritrocitos/parasitología , Células HeLa , Humanos , Parasitemia/tratamiento farmacológico , Plasmodium falciparum/crecimiento & desarrollo , Esquizontes/efectos de los fármacos , Trofozoítos/efectos de los fármacos
20.
Mov Disord ; 21(11): 1990-4, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16991157

RESUMEN

The purpose of our study was to prospectively evaluate cardiac [(123)I]metaiodobenzylguanidine (MIBG) uptake in patients with cerebrovascular disease (CVD) who develop clinical symptoms of vascular Parkinsonism (VP). A total of 19 consecutive patients who developed Parkinsonism during the course of their CVD were enrolled in the study; 16 age-matched subjects, and 30 patients with Parkinson's disease (PD) were also evaluated with cardiac MIBG uptake. MIBG uptake was assessed using the ratio of the heart to the upper mediastinum (H/M) according to planar scintigraphic data. The mean H/M ratio was significantly higher in patients with VP than in those with PD (2.28 +/- 0.41 vs. 1.27 +/- 0.13; P < 0.001). MIBG uptake did not differ between VP and controls (2.46 +/- 0.33; P > 0.05). Our findings suggest that myocardial postganglionic sympathetic dysfunction found in PD is absent in most patients with VP. MIBG single photon emission computed tomography imaging may be useful to help distinguish between PD and VP patients in clinical practice.


Asunto(s)
3-Yodobencilguanidina/farmacocinética , Trastornos Cerebrovasculares/diagnóstico por imagen , Corazón/diagnóstico por imagen , Trastornos Parkinsonianos/diagnóstico por imagen , Radiofármacos/farmacocinética , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Trastornos Cerebrovasculares/tratamiento farmacológico , Trastornos Cerebrovasculares/metabolismo , Femenino , Corazón/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Trastornos Parkinsonianos/tratamiento farmacológico , Trastornos Parkinsonianos/metabolismo , Cintigrafía/métodos
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