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1.
Chin J Physiol ; 64(5): 225-231, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34708714

RESUMEN

Ultra-marathons are typically held over harsh terrains such as mountains, deserts, or other wilderness, and place severe demands on the physical and psychological capabilities of participants. Adventure-race competitors commonly report hallucinations. The goal of this study was to gain insight into visual hallucinations (VHs) during a mountain ultra-marathon. Thirty-one Taiwanese runners who participated in the 2018 Run Across Taiwan Ultra-Marathon, which spans 246 km with an altitude difference of 3266 m and an overall cut-off time of 44 h, volunteered for this study. Self-reported questionnaires on sleep duration, hallucinatory experiences, clinical symptoms of cold- and heat-related illnesses, and the 2018 Lake Louise Acute Mountain Sickness (AMS) Score were recorded prerace, during the summit, immediately postrace, and 3-days postrace. Hematological samples were collected 1 week before, immediately after, and 3 days after the race. Eight ultra-marathoners (six males and two females; seven finishers and one withdrawer) were recruited. Three out of eight (37.5%) subjects (two males and one female) reported experiencing VHs during the last 60 km. Three out of five (60%) lower-ranked subjects experienced VHs. All eight runners slept for <30 min during the race. None of the runners presented with headache either during or after the race to meet the criteria for AMS. None of the runners suffered an abnormal thermoregulatory response or a hypoglycemic episode throughout the ultra-marathon. The changes in blood osmolality immediately postrace were subclinical, despite being statistically significant. Among the three runners with VHs, none presented with severe dehydration or dysnatremia immediately postrace. High-altitude exposure, hyper/hypothermia, dehydration, dysnatermia, or hypoglycemia did not seem to contribute to hallucination onset in our subjects during the event. VHs of ultra-marathoners may be associated with excessive physical exertion and sleep deprivation.


Asunto(s)
Altitud , Carrera de Maratón , Femenino , Alucinaciones/epidemiología , Alucinaciones/etiología , Humanos , Masculino , Taiwán
2.
J Clin Nurs ; 28(3-4): 545-559, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30091495

RESUMEN

AIMS AND OBJECTIVES: To determine the comparative efficacy of developmental care versus standard care for reducing pain and stress in preterm infants during examinations for retinopathy of prematurity (ROP). BACKGROUND: ROP examinations are routinely performed in neonatal intensive care units to detect these lesions. Pain scores recorded during and after eye examinations have revealed physiological and behavioural manifestations of pain and stress. DESIGN: A randomised crossover trial was conducted. METHODS: Fourteen preterm infants were evaluated. The modified developmental care bundle included environmental modifications, positioning and containment, oxygen supplementation, interaction and approach and cue-based individual care, which were applied before, during and after the ROP examination. The primary outcomes were obtained from pain and stress scores using the premature infant pain profile-revised (PIPP-R) and a behavioural evaluation. The secondary outcomes were recovery time to the baseline of the vital signs and oxygen saturation. RESULTS: Statistical significances were found in the care type comparison (p = 0.013), time comparison (p < 0.001) and type-by-time interaction (p = 0.005) in the PIPP-R, and also in the care type comparison (p < 0.001), time comparison (p < 0.001) and type-by-time interaction (p = 0.001) in the behavioural evaluation scores using a generalised estimating equation (GEE) analysis. Recovery time for the developmental care (N = 13, mean = 8.6 ± 11.5 min, 95% CI = 1.68-15.57) was significantly shorter than for the standard care (N = 11, mean = 25.5 ± 20.8 min, 95% CI = 11.45-39.46), which was found to be statistically significant according to the Wilcoxon signed-rank test (N = 11, p = 0.003). CONCLUSIONS: A bundled developmental care intervention significantly reduced pain and stress responses and the time needed for infants to recover their physiological status following the procedure. RELEVANCE TO CLINICAL PRACTICE: Since the results show the benefits of developmental care in an ROP examination, it can be the practical evidence basis by which to develop a standard of procedure or guideline for clinical practice.


Asunto(s)
Dimensión del Dolor/enfermería , Paquetes de Atención al Paciente/enfermería , Retinopatía de la Prematuridad/diagnóstico , Estrés Fisiológico , Estudios Cruzados , Técnicas de Diagnóstico Oftalmológico/psicología , Femenino , Edad Gestacional , Humanos , Recién Nacido , Recien Nacido Prematuro , Recién Nacido de muy Bajo Peso , Unidades de Cuidado Intensivo Neonatal , Masculino , Dimensión del Dolor/métodos , Retinopatía de la Prematuridad/psicología , Factores de Tiempo
3.
Zoolog Sci ; 35(4): 330-352, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30079836

RESUMEN

Few convenient/expeditious methods for identifying the species of shed snake skins in specific areas have been developed. The scales on shed snake skins are permeable to light and can be examined by light microscopy (LM), which is of higher availability-especially for wild animal researchers and citizen scientists-than conventional approach which examines the scale microstructures by scanning electron microscopy. We collected and examined a total of 801 shed samples or scale specimens from 53 snake species in Taiwan and adjacent islands, and developed the first guide to identify the fragmented or faded shed skins of most snake species by LM. Morphological characters of scales can be examined by LM include the apical notch, apical pits, apical lobes, keels, scale symmetry, unpigmented spots (mechanoreceptor-like organs), interscale follicles, cross/longitudinal micro-ridge, oberhautchen cells, rows of spines, light/tiny dots, and other microstructures. The microstructures on the scale specimens prepared by the stripped method and the impression method were similar to those on shed skins when examined by LM. We investigated the variations of scale morphology associated with ontogeny, body region, and position on scales, discussed the character evolution of snake scale morphology, and certified that the interscale follicles and the unpigmented spots could also be useful characters for shed skin identification. The methods and results of this study could be applied to identify squamate skins/sloughs and even fecal remnants.


Asunto(s)
Muda/fisiología , Piel , Serpientes/clasificación , Serpientes/fisiología , Escamas de Animales/fisiología , Animales , Pigmentos Biológicos , Especificidad de la Especie
4.
Wound Repair Regen ; 24(2): 287-301, 2016 03.
Artículo en Inglés | MEDLINE | ID: mdl-26472668

RESUMEN

Several reagents have been studied to overcome the problems encountered with antiseptic use, such as moderate cutaneous wound cytotoxicity and skin thinning. We successfully prepared a gelatin/chitosan/epigallocatechin gallate nanoparticle incorporated in a poly(γ-glutamic acid)/gelatin hydrogel, which comprised activated carbon fibers with gentamicin, to fabricate a sandwiched dressing to enhance wound regeneration. The inner layer of activated carbon fibers with gentamicin was designed to prevent bacterial infection, and the outer layer of gelatin/chitosan/epigallocatechin gallate nanoparticles incorporated in a poly(γ-glutamic acid)/gelatin hydrogel was designed to prevent inflammation and facilitate reepithelialization. An in vitro study demonstrated that the dressing effectively inhibited target microorganisms, and scanning electron microscope and confocal laser scanning microscope indicated that the nanoparticles were homogeneously dispersed and migrated into the hydrogel. The in vivo study reported that the sandwiched dressing, comprising the poly(γ-glutamic acid)/gelatin hydrogel, was easy to remove from the wound and facilitated wound tissue regeneration and accelerated healing process.


Asunto(s)
Vendajes , Catequina/análogos & derivados , Cicatrización de Heridas/efectos de los fármacos , Heridas y Lesiones/tratamiento farmacológico , Heridas y Lesiones/patología , Animales , Antibacterianos/farmacología , Materiales Biocompatibles/farmacología , Catequina/administración & dosificación , Catequina/farmacología , Catequina/uso terapéutico , Células Cultivadas , Quitosano/farmacología , Modelos Animales de Enfermedad , Sistemas de Liberación de Medicamentos , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Gelatina/farmacología , Gentamicinas/farmacología , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacología , Masculino , Ensayo de Materiales , Nanopartículas , Ácido Poliglutámico/análogos & derivados , Ácido Poliglutámico/farmacología , Ratas , Ratas Sprague-Dawley , Repitelización
5.
Molecules ; 21(2): 136, 2016 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-26805809

RESUMEN

The whole plant of Anisomeles ovata has been widely used in Taiwan for treating inflammation-related skin and liver diseases, however, the detailed pharmacology mechanisms have yet to be elucidated. In the present study, one of the major components, 5,6,4'-trihydroxy-7,3'-dimethoxyflavone (5-TDMF), was purified from a methanol extract of Anisomeles ovata. A pharmacological study of this compound suggests that 5-TDMF possesses potent free radical scavenging activity both in vitro and ex vivo. Furthermore, 5-TDMF reduces nitric oxide and pro-inflammatory cytokine production in LPC-treated RAW 264.7 cells through the attenuation of nitric oxide synthase and cyclooxygenase-2. Additional experiments suggest that of 5-TDMF interferes with nuclear factor-κB translocation and mitogen-activated protein kinase pathways. These results identify 5-TDMF as an anti-oxidant and anti-inflammatory compound, explain the pharmacologic function of Anisomeles ovata and suggest its great potential as a new anti-inflammatory remedy.


Asunto(s)
Antiinflamatorios/farmacología , Antioxidantes/farmacología , Flavonas/farmacología , Lipopolisacáridos/efectos adversos , Macrófagos/efectos de los fármacos , Animales , Ciclooxigenasa 2/metabolismo , Flavonas/aislamiento & purificación , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Lamiaceae/química , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa/metabolismo , Células RAW 264.7
6.
BMC Pediatr ; 15: 55, 2015 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-25947200

RESUMEN

BACKGROUND: Acute mountain sickness (AMS) is commonly found among people traveling above 2500 m. We investigated whether the occurrence of AMS is related to differences in individual physical fitness and BMI in subjects 11-13 years of age. METHODS: This study was conducted at Xue Mountain, Taiwan (elevation of 3886 m) between June 13, 2011 and June 17, 2011. Subjects were asked to ascend from Taipei City (25 m) to the summit (3886 m) over 3 days and 2 nights. Gender, age, weight, height, and fitness index (determined using a 3-minute step test) were recorded at sea level before ascent. The Lake Louise AMS score was used to record symptoms and diagnose AMS. RESULTS: A total of 179 subjects (mean age: 11.8 years; 102 males, 77 females) were included in the analysis. A total of 44.7% of subjects were diagnosed with AMS. Male gender (p = 0.004) and elevated body mass index (BMI) (p < 0.001) were each associated with the development of AMS. However the physical fitness index was comparable in subjects with and without AMS (67.8 ± 10.1 vs. 68.0 ± 9.3, p = 0.9). CONCLUSIONS: This study shows that both BMI and male gender were associated with the development of AMS in 11-13 year old children. Physical fitness was not associated with the occurrence of AMS.


Asunto(s)
Mal de Altura/epidemiología , Índice de Masa Corporal , Aptitud Física , Adolescente , Distribución por Edad , Niño , Femenino , Humanos , Incidencia , Modelos Logísticos , Masculino , Estudios Prospectivos , Distribución por Sexo , Taiwán/epidemiología
7.
Clin J Sport Med ; 25(1): 49-54, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24949829

RESUMEN

OBJECTIVE: To evaluate the prevalence and characteristics of acute kidney injury (AKI) in 100-km ultramarathon runners. DESIGN: Prospective observational study. SETTING: The 2011 Soochow University ultramarathon, in which each athlete ran for 100 km. PARTICIPANTS: All Taiwanese entrants who participated in the 100-km race and lived in the northern part of Taiwan were invited to participate in the study. MAIN OUTCOME MEASURES: Acute kidney injury was defined using the Acute Kidney Injury Network criteria. Blood and urine samples were collected 1 week before, immediately after, and 1 day after the race. RESULTS: Immediately after the race, 85% (22) of the 26 subjects were diagnosed with AKI, 65% (16) with moderate dehydration, 23% (6) with muscle cramps, and 12% (3) with hematuria. Body weight was significantly decreased from prerace to all postrace measurements. Plasma levels of potassium ion, creatinine, renin, and aldosterone were significantly elevated immediately after the race and then significantly reduced 1 day after the race. Changes in plasma levels of sodium, creatine kinase, and creatine kinase-MB, as well as urine potassium and creatinine, were indicative of AKI. CONCLUSIONS: Transient AKI and muscle cramps are very common in 100-km ultramarathon runners. All transient ultra-runners who developed AKI in this study recovered their renal function 1 day later. CLINICAL RELEVANCE: Ultramarathon running is associated with a wide range of significant changes in hematological parameters, several of which can be associated with potentially serious renal and physiological abnormalities.


Asunto(s)
Lesión Renal Aguda/epidemiología , Deshidratación/epidemiología , Hematuria/epidemiología , Calambre Muscular/epidemiología , Carrera/lesiones , Lesión Renal Aguda/sangre , Lesión Renal Aguda/orina , Adulto , Aldosterona/sangre , Estudios de Cohortes , Creatina Quinasa/sangre , Forma MB de la Creatina-Quinasa/sangre , Creatinina/sangre , Creatinina/orina , Deshidratación/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Calambre Muscular/sangre , Potasio/sangre , Prevalencia , Estudios Prospectivos , Renina/sangre , Sodio/sangre , Taiwán/epidemiología , Adulto Joven
8.
Clin J Sport Med ; 25(2): 95-104, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24751723

RESUMEN

OBJECTIVE: To examine the effect of ascent rate on the induction of acute mountain sickness (AMS) in young adults during a climb to Jiaming Lake (3350 m) in Taiwan. DESIGN: Prospective, nonrandomized. SETTING: Climb from 2370 to 3350 m. PARTICIPANTS: Young adults (aged 18 to 26 years) (N = 91) chose to participate in either the fast ascent (3 days; n = 43) or slow ascent (4 days; n = 48) group (1 and 2). ASSESSMENT OF RISK FACTORS: Two criteria were used to define AMS. A Lake Louise score ≥3 and Lake Louise criteria [in the setting of a recent gain in altitude, the presence of headache and at least 1 of gastrointestinal discomfort (anorexia, nausea, or vomiting), fatigue or weakness, dizziness or lightheadedness, or difficulty sleeping]. MAIN OUTCOME MEASURES: Heart rate, blood oxygen saturation (SaO2), and symptoms of AMS were monitored each morning and evening. RESULTS: Baseline characteristics were similar between groups, except for significant differences in history of alcohol consumption (P = 0.009) and climbing experience above 3000 m (P < 0.001). The incidence of AMS was not associated with the rate of ascent. Acute mountain sickness was most prevalent in group 1 on day 2 in the evening and in group 2 on day 3 in the evening. In both groups, AMS correlated with the initial reduction in SaO2. Body mass index (BMI) >24 kg/m was identified as a significant risk factor for AMS. CONCLUSIONS: The development of AMS was closely associated with an initial reduction in SaO2. A BMI >24 kg/m also contributed to the occurrence of AMS. CLINICAL RELEVANCE: These findings indicate that factors other than ascent rate should be considered when trying to ameliorate the risk of AMS.


Asunto(s)
Mal de Altura/epidemiología , Sobrepeso/epidemiología , Oxígeno/metabolismo , Adolescente , Adulto , Mal de Altura/fisiopatología , Índice de Masa Corporal , Ejercicio Físico , Frecuencia Cardíaca , Humanos , Oximetría , Prevalencia , Estudios Prospectivos , Análisis de Regresión , Factores de Riesgo , Conducta Sedentaria , Taiwán , Factores de Tiempo , Adulto Joven
10.
J Chin Med Assoc ; 87(6): 643-652, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38838200

RESUMEN

BACKGROUND: Early palliative care (EPC) benefits some cancers, but its clinical outcomes differ depending on patients' racial and ethnic disparities, and customs. To determine whether EPC improves symptoms, emotional distress, and quality of life among Taiwanese patients with early or advanced-stage head and neck cancer (HNC). METHODS: Based on participants' pathological stages, they were categorized as having early and advanced-stage HNC. Those willing and unwilling to undergo EPC were assigned to the EPC and standard groups, respectively. Their daily cancer-related symptoms were assessed using the Distress Thermometer (DT) and MD Anderson Symptom Inventory (MDASI), whose scores' concurrent validity was evaluated using the European Organization for Research and Treatment of Core Quality of Life (EORTC-QLQ-C30) and Head and Neck 35 (EORTC-QLQ-H&N35) questionnaires. RESULTS: Patients (n = 93) diagnosed with HNC at Taiwan's Chia-Yi Christian Hospital from November 2020 to October 2022 were recruited. The patients voluntarily split into two groups: EPC groups and standard groups (23 and 11 in early-stage; 46 and 13 in advanced-stage, respectively). DT assessment showed significant emotional distress improvements for all patients with HNC who received EPC. The EORTC-QLQ-C30 questionnaire indicated that, compared to standard interventions, EPC groups significantly improved the quality of life and some symptoms for both early and advanced-stage HNC patients. However, the EORTC-QLQ-H&N35 questionnaire found no significant difference between the two groups. Furthermore, advanced-stage patients' anticancer treatment completion rates with EPC and standard interventions were 95.35% and 75%, respectively. CONCLUSION: EPC improves symptoms, emotional distress, quality of life, and treatment completion rates in Taiwanese patients with early or advanced-stage HNC. Nonetheless, further extensive clinical studies are required for validation.


Asunto(s)
Neoplasias de Cabeza y Cuello , Cuidados Paliativos , Calidad de Vida , Humanos , Neoplasias de Cabeza y Cuello/terapia , Neoplasias de Cabeza y Cuello/psicología , Masculino , Femenino , Persona de Mediana Edad , Anciano , Taiwán , Adulto , Encuestas y Cuestionarios
11.
Biochim Biophys Acta ; 1820(7): 1149-57, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22348919

RESUMEN

BACKGROUND: Skin cancers are reportedly increasing worldwide. Developing novel anti-skin cancer drugs with minimal side effects is necessary to address this public health issue. Sinuleptolide has been demonstrated to possess anti-cancer cell activities; however, the mechanisms underlying the anti-skin cancer effects of 5-epi-sinuleptolide and sinuleptolide remain poorly understood. METHODS: Apoptosis cell, cell-cycle-related regulatory factors, and mitochondria- and death receptor-dependent caspase pathway in 5-epi-sinuleptolide-induced cell apoptosis were examined using SCC25 cells. RESULTS: 5-epi-Sinuleptolide inhibited human skin cancer cell growth more than did sinuleptolide. Treatment of SCC25 cells with 5-epi-sinuleptolide increased apoptotic body formation, and induced cell-cycle arrest during the G2/M phase. Notably, 5-epi-sinuleptolide up-regulated p53 and p21 expression and inhibited G2/M phase regulators of cyclin B1 and cyclin-dependent kinease 1 (CDK1) in SCC25 cells. Additionally, 5-epi-sinuleptolide induced apoptosis by mitochondria-mediated cytochrome c and Bax up-expression, down-regulated Bcl-2, and activated caspase-9 and -3. 5-epi-Sinuleptolide also up-regulated tBid, which is associated with up-regulation of tumor necrosis factor-α (TNF-α) and Fas ligand (FasL) and their cognate receptors (i.e., TNF-RI, TNF-R2 and Fas), downstream adaptor TNF-R1-associated death domain (TRADD) and Fas-associated death domain (FADD), and activated caspase-8 in SCC25 cells. CONCLUSIONS: The analytical results indicate that the death receptor- and mitochondria-mediated caspase pathway is critical in 5-epi-sinuleptolide-induced apoptosis of skin cancer cells. GENERAL SIGNIFICANCE: This is the first report suggesting that the apoptosis mediates the anti-tumor effect of 5-epi-sinuleptolide. The results of this study might provide useful suggestions for designing of anti-tumor drugs for skin cancer patients.


Asunto(s)
Apoptosis/efectos de los fármacos , Carcinoma de Células Escamosas/tratamiento farmacológico , Caspasas/metabolismo , Puntos de Control del Ciclo Celular/efectos de los fármacos , Diterpenos/farmacología , Mitocondrias/efectos de los fármacos , Neoplasias Cutáneas/tratamiento farmacológico , Factor de Necrosis Tumoral alfa/metabolismo , Western Blotting , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Supervivencia Celular/efectos de los fármacos , Proteína Ligando Fas/metabolismo , Técnica del Anticuerpo Fluorescente , Humanos , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/efectos de los fármacos , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología , Ligando Inductor de Apoptosis Relacionado con TNF/genética , Ligando Inductor de Apoptosis Relacionado con TNF/metabolismo , Células Tumorales Cultivadas
12.
Eur J Nutr ; 52(1): 57-65, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22160169

RESUMEN

PURPOSE: We aimed to investigate the association of body mass index (BMI), waist circumference (WC), and waist-to-height ratio (WHtR) with cardiometabolic risk. METHODS: In this cross-sectional study, 21,038 men and 15,604 women who participated in a health check-up were included. RESULTS: In both men and women, the area under the curve (AUC) of WHtR was significantly greater than that of BMI or WC in the prediction of diabetes, hypertension, high total cholesterol, high triglycerides, and low HDL-cholesterol (P < 0.05 for all). The AUC for WHtR in the prediction of metabolic syndrome (MS) was also highest in the women (P < 0.05). After adjustment for potential confounders, the odds ratios and 95% confidence intervals for MS for each standard deviation increase in BMI, WHtR, and WC were 1.47 (1.46-1.49), 1.32 (1.31-1.33), and 1.19 (1.18-1.19), respectively. Finally, patients of either sex with a normal BMI or WC level, but with an elevated WHtR, had higher levels of various cardiometabolic risk factors in comparison with their normal BMI or WC, but low WHtR, counterparts (P < 0.05 for all). CONCLUSION: Among Taiwanese adults, a WHtR greater than 0.5 is a simple, yet effective indicator of centralized obesity and associated cardiometabolic risk, even among individuals deemed 'healthy' according to BMI and WC.


Asunto(s)
Estatura , Índice de Masa Corporal , Peso Corporal , Enfermedades Cardiovasculares/epidemiología , Síndrome Metabólico/epidemiología , Circunferencia de la Cintura , Adulto , Área Bajo la Curva , Pueblo Asiatico , Presión Sanguínea , Enfermedades Cardiovasculares/complicaciones , Enfermedades Cardiovasculares/diagnóstico , Estudios Transversales , Femenino , Humanos , Hipertensión/complicaciones , Hipertensión/epidemiología , Modelos Logísticos , Masculino , Síndrome Metabólico/complicaciones , Síndrome Metabólico/diagnóstico , Persona de Mediana Edad , Obesidad/complicaciones , Obesidad/epidemiología , Oportunidad Relativa , Factores de Riesgo , Taiwán/epidemiología
13.
J Chem Phys ; 138(19): 194901, 2013 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-23697435

RESUMEN

A density functional theory is developed for the diblock copolymer melt, where one block contains the segment orientation dependent chiral interaction. In addition to the standard (scalar) pair interaction between the two types of monomers, the chiral block has the additional pairwise interaction, which is linear in the tangent vectors of the segments. We construct a density functional, which contains both the scalar density field and the vector chain alignment field. The quadratic part of the density functional comes from the mean field theory of the microscopic model, whereas the fourth order terms are introduced phenomenologically in the spatially local form. From the stability analysis of this model, we find that the additional chiral interaction shifts the order-disorder transition, which is consistent with the behavior of experimental system. Further numerical calculation reveals a new metastable chiral helical cylinder structure, which is similar to the one found experimentally. Another similar metastable structure but with zigzag modulation is also observed. As the helical and zigzag structures disappear when the chiral interaction is switched off, we understand that the chiral effect is the driving force for the formation of these exotic metastable structures.


Asunto(s)
Polímeros/química , Teoría Cuántica , Congelación
14.
Am J Emerg Med ; 31(7): 1113-7, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23688567

RESUMEN

OBJECTIVE: The objective of this study is to determine the association between the duration of high-altitude (>3000 m) pre-exposure and acute mountain sickness (AMS) incidence. METHODS: A prospective observational study was conducted on 2 random days each month from April 2007 to March 2008 at Paiyun Lodge (3402 m), Jade Mountain, Taiwan. Demographic data, prior AMS history, symptoms, and scores and the days and times of high-altitude pre-exposure within the preceding 2 months were obtained from lowland (<1500 m) trekkers. RESULTS: Totally, 1010 questionnaires were analyzed; 106, 76, and 828 trekkers had pre-exposure lasting at least 3 days (group 1), less than 3 days (group 2), and 0 days (group 3), respectively. Acute mountain sickness incidence was significantly higher in groups 2 and 3 than in group 1 (21.70%, 35.53%, 37.08%, respectively; P = .008). Logistic regression analysis indicated a significantly lower AMS risk in group 1 (group 1, P = .004; odds ratio [OR], 0.479; 95% confidence interval [CI], 0.290-0.791; group 2, P = .226; OR, 0.725; 95% CI, 0.430-1.221). In group 1, 28 and 78 trekkers had single and intermittent multiple pre-exposure, respectively. There was no difference in the incidence or severity of AMS symptoms between single and intermittent multiple pre-exposure (AMS, P = .838; headache, P = .891; dizziness or lightheadedness, P = .414; fatigue and/or weakness, P = .957; gastrointestinal symptoms, P = .257; difficulty sleeping, P = .804; AMS score, P = .796). CONCLUSIONS: High-altitude pre-exposure lasting at least 3 days within the preceding 2 months was associated with a significant lower AMS incidence during a subsequent ascent among Jade Mountain trekkers.


Asunto(s)
Aclimatación , Mal de Altura/etiología , Montañismo , Enfermedad Aguda , Adulto , Mal de Altura/epidemiología , Mal de Altura/prevención & control , Femenino , Humanos , Incidencia , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios , Taiwán , Factores de Tiempo
15.
BMC Complement Altern Med ; 13: 298, 2013 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-24176010

RESUMEN

BACKGROUND: Rhodiola crenulata (R. crenulata) is widely used to prevent acute mountain sickness in the Himalayan areas and in Tibet, but no scientific studies have previously examined its effectiveness. We conducted a randomized, double-blind, placebo-controlled crossover study to investigate its efficacy in acute mountain sickness prevention. METHODS: Healthy adult volunteers were randomized to 2 treatment sequences, receiving either 800 mg R. crenulata extract or placebo daily for 7 days before ascent and 2 days during mountaineering, before crossing over to the alternate treatment after a 3-month wash-out period. Participants ascended rapidly from 250 m to 3421 m on two separate occasions: December 2010 and April 2011. The primary outcome measure was the incidence of acute mountain sickness, as defined by a Lake Louise score ≥ 3, with headache and at least one of the symptoms of nausea or vomiting, fatigue, dizziness, or difficulty sleeping. RESULTS: One hundred and two participants completed the trial. There were no demographic differences between individuals taking Rhodiola-placebo and those taking placebo-Rhodiola. No significant differences in the incidence of acute mountain sickness were found between R. crenulata extract and placebo groups (all 60.8%; adjusted odds ratio (AOR) = 1.02, 95% confidence interval (CI) = 0.69-1.52). The incidence of severe acute mountain sickness in Rhodiola extract vs. placebo groups was 35.3% vs. 29.4% (AOR = 1.42, 95% CI = 0.90-2.25). CONCLUSIONS: R. crenulata extract was not effective in reducing the incidence or severity of acute mountain sickness as compared to placebo. TRIAL REGISTRATION: ClinicalTrials.gov NCT01536288.


Asunto(s)
Mal de Altura/prevención & control , Extractos Vegetales/administración & dosificación , Rhodiola/química , Enfermedad Aguda/terapia , Adulto , Mal de Altura/tratamiento farmacológico , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
16.
J Emerg Med ; 44(1): e57-60, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22244603

RESUMEN

BACKGROUND: Hypermagnesemia is a rare condition that is usually iatrogenic. Magnesium oxide (MgO) ingestion by constipated patients with prolonged colonic retention contributes to hypermagnesemia. Treatment of hypermagnesemia includes discontinuation of the magnesium use, gastrointestinal (GI) decontamination, and removal of magnesium from the serum by dialysis. Calcium acts as an antagonist in hypermagnesemia. CASE REPORT: A 72-year-old woman presented with constipation and MgO ingestion. The patient was brought to our department due to altered mental status and progressive general weakness. Laboratory tests showed a magnesium level of 6.2 mEq/L. Bradycardia and hypotension developed with rebound hypermagnesemia after incomplete dialysis. Abdomen computed tomography showed hyperdense MgO tablets retained in the colon. A magnesium-free laxative was used for GI decontamination. Despite the use of high-dose inotropics and an elevated trigger for transcutaneous pacing, the cardiac performance improved minimally. Although our patient responded to calcium administration with hemodynamic improvement, prolonged hypotension and decreased perfusion led to hypoxic encephalopathy. CONCLUSION: This report demonstrates that MgO tablets retained in the GI tract without adequate decontamination result in continuous absorption and rebound of hypermagnesemia. This report also addresses the importance of GI decontamination in the treatment of hypermagnesemia.


Asunto(s)
Catárticos/efectos adversos , Estreñimiento , Óxido de Magnesio/efectos adversos , Magnesio/sangre , Anciano , Estreñimiento/complicaciones , Estreñimiento/tratamiento farmacológico , Femenino , Humanos , Hipotensión/etiología , Laxativos/uso terapéutico , Resultado del Tratamiento
17.
Cardiovasc Diabetol ; 11: 40, 2012 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-22533665

RESUMEN

BACKGROUND: Serum C-reactive protein (CRP) and leptin levels have been independently associated with the cardiovascular risk factors. The aim of the present study was to determine if their serum levels were associated with cardiovascular risk factors or metabolic syndrome as well as their correlation in the Taiwanese population. METHODS: This retrospective study included 999 subjects (> 18 y), who underwent a physical examination in Chang-Gung Memorial Hospital-Linkou and Chiayi in Taiwan. The associations between CRP and/or leptin levels and cardiovascular risk factors and metabolic syndrome were determined using independent two sample t-tests to detect gender differences and chi-square tests to evaluate differences in frequencies. To compare the means of the variables measured among the four groups (high and low leptin and high and low CRP), analysis of variance (ANOVA) was used. RESULTS: Both CRP and leptin levels were independently associated with several cardiovascular risk factors, including diabetes, hypercholesterolemia and metabolic syndrome in both men and women (P < 0.05). In addition, a positive correlation between leptin and CRP levels was observed in both genders. Both high-CRP and high-leptin were associated with high blood glucose, waist circumference and serum triglyceride. Whereas increased metabolic syndrome incidence was observed in males with elevated leptin regardless of CRP levels, females with elevated CRP or leptin had increased incidence of metabolic syndrome. CONCLUSION: Both leptin and CRP levels were associated with cardiovascular risk factors as well as metabolic syndrome score in both men and women although gender-specific differences were observed. Thus, CRP and leptin may represent useful biomarkers for predicting the onset of cardiovascular disease or metabolic syndrome in Taiwanese adults. TRIAL REGISTRATION: IRB/CGMH 100-3514B.


Asunto(s)
Pueblo Asiatico , Proteína C-Reactiva/análisis , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/etnología , Leptina/sangre , Síndrome Metabólico/sangre , Síndrome Metabólico/etnología , Adulto , Factores de Edad , Análisis de Varianza , Biomarcadores/sangre , Enfermedades Cardiovasculares/diagnóstico , Distribución de Chi-Cuadrado , Estudios Transversales , Diabetes Mellitus/sangre , Diabetes Mellitus/etnología , Femenino , Humanos , Hipercolesterolemia/sangre , Hipercolesterolemia/etnología , Incidencia , Masculino , Síndrome Metabólico/diagnóstico , Persona de Mediana Edad , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores Sexuales , Taiwán/epidemiología
18.
Wilderness Environ Med ; 23(2): 122-7, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22656657

RESUMEN

OBJECTIVE: The purpose of this trial was to establish whether changes in resting oxygen saturation (Spo(2)) during ascent of Jade Mountain is useful in predicting acute mountain sickness (AMS). AMS-risk factors were also assessed. METHODS: A prospective trial was conducted on Jade Mountain, Taiwan from October 18 to October 27, 2008. Resting oxygen saturation (Spo(2)) and heart rate (HR) were measured in subjects at the trail entrance (2610 m), on arrival at Paiyun Lodge (3402 m) on day 1, and at Paiyun Lodge after reaching the summit (3952 m) the next day (day 2). AMS was diagnosed with Lake Louise criteria (AMS score ≥4). A total of 787 subjects were eligible for analysis; 286 (32.2%) met the criteria for AMS. RESULTS: Subjects who developed AMS had significantly lower Spo(2) than those who did not at the trail entrance (93.1% ± 2.1% vs 93.5% ± 2.3%; P = .023), on arrival at Paiyun Lodge on day 1 (86.2% ± 4.7% vs 87.6% ± 4.3%; P < .001), and on the return back to the Paiyun Lodge after a summit attempt on day 2 (85.5% ± 3.5% vs 89.6% ± 3.2%; P < .001), respectively. Trekkers with AMS were significantly younger (40.0 vs 43.2 years; P < .001), and had less high altitude (>3000 m) travel in the previous 3 months (29.9% vs 37.1%; P = .004). CONCLUSIONS: Subjects with AMS had a lower Spo(2) than those without AMS; however, the differences between the 2 groups were not clinically significant. The results of this study do not support the use of pulse oximetry in predicting AMS on Jade Mountain.


Asunto(s)
Aclimatación/fisiología , Mal de Altura/sangre , Frecuencia Cardíaca/fisiología , Consumo de Oxígeno/fisiología , Oxígeno/sangre , Adulto , Factores de Edad , Mal de Altura/epidemiología , Femenino , Humanos , Masculino , Montañismo , Estudios Prospectivos , Taiwán/epidemiología
19.
Am J Chin Med ; 50(5): 1281-1298, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35670059

RESUMEN

Cisplatin is massively used to treat solid tumors. However, several severe adverse effects, such as cardiotoxicity, are obstacles to its clinical application. Cardiotoxicity may lead to congestive heart failure and even sudden cardiac death in patients receiving cisplatin. Therefore, finding a novel therapeutic strategy for the prevention of cisplatin-induced cardiotoxicity is urgent. Quercetin is a flavonol compound that can be found in dietary fruits and vegetables. The antioxidant function and anti-inflammatory capacity of quercetin have been reported. However, whether quercetin could protect against cisplatin-caused apoptosis and cellular damage in cardiomyocytes is still unclear. H9c2 cardiomyocytes were treated with cisplatin (40 µM) for 24 h to induce cellular damage with or without quercetin pretreatment. We found that quercetin activates Nrf2 and HO-1 expression, thereby mitigating cisplatin-caused cytotoxicity in H9c2 cells. Quercetin also increases SOD levels, maintains mitochondrial function, and reduces oxidative stress under cisplatin stimulation. Quercetin attenuates cisplatin-induced apoptosis and inflammation in H9c2 cardiomyocytes; however, these cytoprotective effects were diminished by silencing Nrf2 and HO-1. In conclusion, this study reports that quercetin has the potential to antagonize cisplatin-caused cardiotoxicity by reducing ROS-mediated mitochondrial damage and inflammation via the Nrf2/HO-1 and p38MAPK/NF-[Formula: see text]Bp65/IL-8 signaling pathway. This study provided the theoretical basis and experimental proof for the clinical application of quercetin as a new effective strategy to relieve chemotherapy-induced cardiotoxicity.


Asunto(s)
Miocitos Cardíacos , Factor 2 Relacionado con NF-E2 , Antioxidantes/farmacología , Apoptosis , Cardiotoxicidad/metabolismo , Cisplatino/efectos adversos , Humanos , Inflamación/metabolismo , Miocitos Cardíacos/metabolismo , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo , Quercetina/metabolismo , Transducción de Señal
20.
ChemSusChem ; 15(5): e202102476, 2022 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-35023634

RESUMEN

Conversion of CO2 into carbonaceous fuels with the aid of solar energy has been an important research subject for decades. Owing to their excellent electron-accepting capacities, fullerene derivatives have been extensively used as n-type semiconductors. This work reports that the fulleropyrrolidine functionalized with 4,7-di(thiophen-2-yl)benzo[c][1,2,5]thiadiazole, abbreviated as DTBT-C60 , could efficiently catalyze the photoreduction of CO2 to CO. The novel C60 -chromophore dyad structure facilitated better usage of solar light and effective dissociation of excitons. Consequently, the DTBT-C60 exhibited a promising CO yield of 144 µmol gcat -1 under AM1.5G solar illumination for 24 h. Moreover, the isotope experiments demonstrated that water molecules could function as an electron source to reactivate DTBT-C60 . Impressively, DTBT-C60 exhibited an extremely durable catalytic activity for more than one week, facilitating the practical application of photochemical CO2 reaction.

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