Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
1.
Front Microbiol ; 15: 1327913, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38426054

RESUMEN

Numerous studies have investigated the effects of stannous ions on specific microbes and their efficacy in reducing dental plaque. Nonetheless, our understanding of their impact on the oral microbiome is still a subject of ongoing exploration. Therefore, this study sought to evaluate the effects of a stannous-containing sodium fluoride dentifrice in comparison to a zinc-containing sodium fluoride dentifrice and a control group on intact, healthy oral biofilms. Utilizing the novel 2bRAD-M approach for species-resolved metagenomics, and FISH/CLSM with probes targeting periodontal and caries associated species alongside Sn2+ and Zn2+ ions, we collected and analyzed in situ biofilms from 15 generally healthy individuals with measurable dental plaque and treated the biofilms with dentifrices to elucidate variations in microbial distribution. Although significant shifts in the microbiome upon treatment were not observed, the use of a stannous-containing sodium fluoride dentifrice primarily led to an increase in health-associated commensal species and decrease in pathogenic species. Notably, FISH/CLSM analysis highlighted a marked reduction in representative species associated with periodontitis and caries following treatment with the use of a stannous-containing sodium fluoride dentifrice, as opposed to a zinc-containing sodium fluoride dentifrice and the control group. Additionally, Sn2+ specific intracellular imaging reflected the colocalization of Sn2+ ions with P. gingivalis but not with other species. In contrast, Zn2+ ions exhibited non-specific binding, thus suggesting that Sn2+ could exhibit selective binding toward pathogenic species. Altogether, our results demonstrate that stannous ions could help to maintain a healthy oral microbiome by preferentially targeting certain pathogenic bacteria to reverse dysbiosis and underscores the importance of the continual usage of such products as a preventive measure for oral diseases and the maintenance of health.

2.
Int J Cosmet Sci ; 2024 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-38433250

RESUMEN

OBJECTIVE: Erythema, characterized by the redness of the skin, is a common skin reaction triggered by various endogenous and exogenous factors. This response is often a result of the activation of underlying inflammatory mechanisms within the skin. The objective of this study is to investigate the potential benefits of applying a combination of skincare ingredients, namely allantoin, bisabolol, D-panthenol and dipotassium glycyrrhizinate (AB5D), in the modulation of inflammatory factors associated with erythema. Additionally, the study aims to elucidate the mechanisms by which these ingredients exert their combined actions to alleviate erythema-associated inflammation. METHODS: Human epidermal keratinocytes were exposed to UVB and subsequently treated with AB5D. Transcriptomics profiling was performed to analyse the dose-response effect of AB5D treatment on keratinocytes. The quantitation of inflammatory mediators, including PGE2 , IL-1α, IL-6, IL-8, IL-1RA and TNFα, was performed on cultured media. Additionally, the oxygen radical absorbance capacity (ORAC) assay was carried out to evaluate the total antioxidant capacity of both individual ingredients and the AB5D combination. To assess the in-vitro antioxidant effects of AB5D against UVB-induced oxidative stress in hTERT keratinocytes, real-time quantitation of mitochondrial superoxide was measured through live-cell imaging. RESULTS: The application of AB5D to UVB-exposed keratinocytes downregulated gene sets associated with inflammatory responses, highlighting the anti-inflammatory properties of AB5D. Specifically, AB5D effectively reduced the production of PGE2 , leading to the downregulation of inflammatory cytokines. Moreover, our findings indicate that AB5D exhibits antioxidative capabilities, functioning as both an antioxidant agent and a regulator of antioxidant enzyme expression to counteract the detrimental effects of cellular oxidative stress. CONCLUSION: We demonstrated that AB5D can reduce UVB-induced PGE2 , IL-1α, IL-6, IL-8, IL-1RA and TNFα as well as mitochondrial superoxide. These findings suggest that AB5D may alleviate erythema by modulating inflammation via PGE2 and through antioxidation mechanisms.


L'érythème, caractérisé par une rougeur sur la peau, est une réaction cutanée fréquente déclenchée par divers facteurs endogènes et exogènes. Il s'agit d'une réponse qui résulte souvent de l'activation des mécanismes inflammatoires sous-jacents dans la peau. OBJECTIF: cette étude vise à étudier les bénéfices potentiels de l'application d'une association d'ingrédients de soins cutanés, à savoir l'allantoïne, le bisabolol, le D-panthénol et le glycyrrhizinate dipotassique (AB5D) dans la modulation des facteurs inflammatoires associés à l'érythème. En outre, l'étude vise à élucider les mécanismes par lesquels ces ingrédients exercent leurs actions combinées pour soulager l'inflammation associée à l'érythème. MÉTHODES: les kératinocytes épidermiques humains ont été exposés aux UVB et traités par la suite par AB5D. Un profilage transcriptomique a été effectué pour analyser l'effet dose-réponse du traitement par AB5D sur les kératinocytes. La quantification des médiateurs inflammatoires, y compris PGE2, IL-1α, IL-6, IL-8, IL-1RA et TNFα, a été effectuée sur des milieux de culture. En outre, le dosage de la capacité d'absorption des radicaux oxygénés (Oxygen Radical Absorbance Capacity, ORAC) a été effectué pour évaluer la capacité antioxydante totale des deux ingrédients individuels et de l'association AB5D. Pour évaluer les effets antioxydants in vitro de l'AB5D contre le stress oxydatif induit par les UVB dans les kératinocytes hTERT, on a mesuré la quantification en temps réel du superoxyde mitochondrial par des tests d'imagerie des cellules vivantes. RÉSULTATS: l'application de l'AB5D aux ensembles de gènes régulés à la baisse exposés aux kératinocytes UVB associés à des réponses inflammatoires, a mis en évidence les propriétés anti-inflammatoires de l'AB5D. Plus précisément, l'AB5D a efficacement réduit la production de PGE2, entraînant une régulation négative des cytokines inflammatoires. En outre, nos résultats indiquent que l'AB5D présente des capacités antioxydantes. Il fonctionne à la fois comme un agent antioxydant et comme un régulateur de l'expression enzymatique antioxydante pour contrer les effets néfastes du stress oxydatif cellulaire. CONCLUSION: nous avons montré que l'AB5D pouvait réduire la PGE2 induite par les UVB, l'IL-1α, l'IL-6, IL-8, IL-1RA et le TNFα, ainsi que le superoxyde mitochondrial. Ces résultats suggèrent que l'AB5D pourrait soulager l'érythème en modulant l'inflammation via la PGE2 et via des mécanismes d'antioxydation.

3.
Imeta ; 2(3): e110, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38867935

RESUMEN

The impact of antibacterial detergent on microbial exchanges and its subsequent effect on malodor in used towels were examined. Homogenization of microbiome among postwashed and indoor dried towels that was dominated by known malodor-producing bacteria. The microbial exchange was attenuated, and the abundance of malodor-producing bacteria was reduced in towels laundered with antibacterial detergent. Reduction of malodorous volatile organic compounds produced from towels laundered with antibacterial detergent.

4.
Sci Rep ; 12(1): 2111, 2022 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-35136124

RESUMEN

Alterations in the three chemosensory modalities-smell, taste, and chemesthesis-have been implicated in Coronavirus Disease 2019 (COVID-19), yet emerging data suggest a wide geographic and ethnic variation in the prevalence of these symptoms. Studies on chemosensory disorders in COVID-19 have predominantly focused on Caucasian populations whereas Asians remain understudied. We conducted a nationwide, multicentre cross-sectional study using an online questionnaire on a cohort of RT-PCR-confirmed adult COVID-19 patients in Malaysia between 6 June and 30 November 2020. The aim of our study was to investigate their presenting symptoms and assess their chemosensory function using self-ratings of perceived smell, taste, chemesthesis, and nasal blockage. In this cohort of 498 patients, 41.4% reported smell and/or taste loss when diagnosed with COVID-19, which was the commonest symptom. Blocked nose, loss of appetite, and gastrointestinal disturbances were independent predictors of smell and/or taste loss on multivariate analysis. Self-ratings of chemosensory function revealed a reduction in smell, taste, and chemesthesis across the entire cohort of patients that was more profound among those reporting smell and/or taste loss as their presenting symptom. Perceived nasal obstruction accounted for only a small proportion of changes in smell and taste, but not for chemesthesis, supporting viral disruption of sensorineural mechanisms as the dominant aetiology of chemosensory dysfunction. Our study suggests that chemosensory dysfunction in COVID-19 is more widespread than previously reported among Asians and may be related to the infectivity of viral strains.Study Registration: NMRR-20-934-54803 and NCT04390165.


Asunto(s)
Prueba de Ácido Nucleico para COVID-19 , Trastornos del Olfato , SARS-CoV-2 , Autoinforme , Encuestas y Cuestionarios , Trastornos del Gusto , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , COVID-19/complicaciones , COVID-19/diagnóstico , COVID-19/epidemiología , COVID-19/fisiopatología , Femenino , Humanos , Malasia/epidemiología , Masculino , Persona de Mediana Edad , Trastornos del Olfato/diagnóstico , Trastornos del Olfato/epidemiología , Trastornos del Olfato/etiología , Trastornos del Olfato/fisiopatología , Trastornos del Gusto/diagnóstico , Trastornos del Gusto/epidemiología , Trastornos del Gusto/etiología , Trastornos del Gusto/fisiopatología
5.
Alzheimers Res Ther ; 13(1): 195, 2021 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-34847922

RESUMEN

BACKGROUND: Southeast Asia represents 10% of the global population, yet little is known about regional clinical characteristics of dementia and risk factors for dementia progression. This study aims to describe the clinico-demographic profiles of dementia in Southeast Asia and investigate the association of onset-type, education, and cerebrovascular disease (CVD) on dementia progression in a real-world clinic setting. METHODS: In this longitudinal study, participants were consecutive series of 1606 patients with dementia from 2010 to 2019 from a tertiary memory clinic from Singapore. The frequency of dementia subtypes stratified into young-onset (YOD; <65 years age-at-onset) and late-onset dementia (LOD; ≥65 years age-at-onset) was studied. Association of onset-type (YOD or LOD), years of lifespan education, and CVD on the trajectory of cognition was evaluated using linear mixed models. The time to significant cognitive decline was investigated using Kaplan-Meier analysis. RESULTS: Dementia of the Alzheimer's type (DAT) was the most common diagnosis (59.8%), followed by vascular dementia (14.9%) and frontotemporal dementia (11.1%). YOD patients accounted for 28.5% of all dementia patients. Patients with higher lifespan education had a steeper decline in global cognition (p<0.001), with this finding being more pronounced in YOD (p=0.0006). Older patients with a moderate-to-severe burden of CVD demonstrated a trend for a faster decline in global cognition compared to those with a mild burden. CONCLUSIONS: There is a high frequency of YOD with DAT being most common in our Southeast Asian memory clinic cohort. YOD patients with higher lifespan education and LOD patients with moderate-to-severe CVD experience a steep decline in cognition.


Asunto(s)
Demencia Vascular , Demencia Frontotemporal , Edad de Inicio , Asia Sudoriental/epidemiología , Demencia Vascular/epidemiología , Humanos , Estudios Longitudinales
6.
Clin Interv Aging ; 16: 301-309, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33642856

RESUMEN

BACKGROUND: Rivastigmine is used to treat cognitive impairment in Alzheimer's disease (AD); however, the efficacy of Rivastigmine in patients with AD and concomitant small vessel cerebrovascular disease (svCVD) remains unclear. We investigated the effectiveness of Rivastigmine Patch in patients with AD and svCVD. METHODS: In this open-label study, 100 patients with AD and MRI confirmed svCVD received 9.5mg/24 hours Rivastigmine transdermal treatment for 24 weeks. The primary outcome was global cognition indexed using the ADAS-Cog. Secondary outcomes included clinical-rated impression of change (indexed using (ADCS-CGIC), activities of daily living (indexed using ADCS-ADL) and side effects. RESULTS: Overall, performance on the ADAS-Cog after 24 weeks deteriorated by 1.78 (SD = 5.29) points. Fifty-two percent of the sample demonstrated improvement or remained stable, while 48% demonstrated worsening of ADAS-Cog scores. Of the 52%, significant improvement (2 or more-point decline) on the ADAS-Cog was observed in 25% of the sample, with a mean change of -5.08 (SD = 3.11). A decline on the ADAS-Cog was observed in 48% of the sample, with a mean change of 6 (SD = 2.98) points. Cognitive outcome did not interact with severity of svCVD. ADCS-ADL scores remained stable from baseline to week 24 and ADCS-CGIC reports indicated that 81% of the patients remained stable after treatment. Side effects were reported by 16% of the patients, with contact dermatitis being the most common. CONCLUSION: Our findings suggest that Rivastigmine may have a role in the management of patients having AD and concomitant mild-severe svCVD, with minimal side effects.


Asunto(s)
Actividades Cotidianas , Enfermedad de Alzheimer , Enfermedades de los Pequeños Vasos Cerebrales , Rivastigmina , Administración Cutánea , Anciano , Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/psicología , Enfermedades de los Pequeños Vasos Cerebrales/complicaciones , Enfermedades de los Pequeños Vasos Cerebrales/diagnóstico , Cognición/efectos de los fármacos , Femenino , Humanos , Masculino , Fármacos Neuroprotectores/administración & dosificación , Fármacos Neuroprotectores/efectos adversos , Rivastigmina/administración & dosificación , Rivastigmina/efectos adversos , Resultado del Tratamiento
8.
J Parkinsons Dis ; 10(3): 1231-1237, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32310187

RESUMEN

BACKGROUND: Mild parkinsonian signs (MPS) are common in the older adult and associated with a wide range of adverse health outcomes. There is limited data on the prevalence of MPS and its significance. OBJECTIVE: To determine the prevalence of MPS in the community ambulant population and to evaluate the relationship of MPS with prodromal features of Parkinson's disease (PD) and cognition. METHODS: This cross-sectional community-based study involved participants aged ≥50 years. Parkinsonian signs were assessed using the modified Unified Parkinson's Disease Rating Scale (mUPDRS) and cognition using the Montreal Cognitive Assessment (MoCA). Premotor symptoms of PD were screened using a self-reported questionnaire. Linear regression was used to assess the association of MPS with premotor symptoms of PD and cognitive impairment. RESULTS: Of 392 eligible participants, MPS was present in 105 (26.8%). Mean age of participants with MPS was 68.8±6.9 years and without MPS was 66.1±5.9 years (p < 0.001). Multivariate analysis revealed that MoCA scores were significantly lower in the MPS group (ß= -0.152, 95% CI = -0.009, -0.138, p < 0.05). A significant correlation between the presence of REM sleep behavior disorder (RBD) and total MPS scores (ß= 0.107, 95% CI = 0.053, 1.490, p < 0.05) was also found. Neither vascular risk factors nor other premotor symptoms were significantly associated with MPS. CONCLUSION: MPS is common and closely related to cognitive impairment and increasing age. Presence of RBD is predictive of higher MPS scores. This study highlights the necessity of other investigations or sensitive risk markers to identify subjects at future risk of PD.


Asunto(s)
Disfunción Cognitiva/epidemiología , Vida Independiente/estadística & datos numéricos , Enfermedad de Parkinson/epidemiología , Síntomas Prodrómicos , Trastorno de la Conducta del Sueño REM/epidemiología , Factores de Edad , Anciano , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/etiología , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/diagnóstico , Prevalencia , Trastorno de la Conducta del Sueño REM/diagnóstico , Trastorno de la Conducta del Sueño REM/etiología , Factores de Riesgo , Índice de Severidad de la Enfermedad
9.
Int Psychogeriatr ; 32(1): 141-149, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31111797

RESUMEN

BACKGROUND: The Visual Cognitive Assessment Test (VCAT) is a language-neutral cognitive screening tool designed for use in culturally diverse populations without the need for translations or adaptations. While it has been established to be language-neutral, the VCAT's construct validity has not been investigated. METHODS: 471 participants were recruited, comprising 233 healthy comparisons, 117 mild cognitive impairment (MCI), and 121 mild Alzheimer's disease (AD) patients. VCAT and domain-specific neuropsychological tests were administered in the same sitting. Construct validity was assessed by analyzing domain-specific associations between the VCAT and well-established cognitive assessments. Reliability (internal consistency) was measured by Cronbach's alpha. Diagnostic ability (area under the curve) and recommended cutoffs were determined by receiver operating characteristic (ROC) analysis. RESULTS: The VCAT and its subdomains demonstrated good construct validity in terms of both convergent and divergent validity and good internal consistency (α = .74). ROC analysis found that the VCAT was on par with the Mini Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA) at distinguishing between healthy comparisons, MCI, and mild AD. Consistent with previous studies, VCAT scores were not affected by language of administration or ethnicity in our cohort. Findings suggest the following cutoffs: Dementia 0-19, MCI 20-24, Normal 25-30. CONCLUSION: This study established the construct validity of the VCAT, which is vital to ensure its subdomains effectively measure the cognitive processes they were designed to. The VCAT is capable of detecting early cognitive impairments and allows for meaningful cross-cultural comparisons, especially useful for international collaborations and clinical trials, and for clinical use in diverse multiethnic populations.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Disfunción Cognitiva/diagnóstico , Pruebas Neuropsicológicas , Anciano , Estudios de Casos y Controles , Cultura , Femenino , Humanos , Lenguaje , Modelos Lineales , Masculino , Persona de Mediana Edad , Estimulación Luminosa , Curva ROC , Reproducibilidad de los Resultados , Singapur
10.
Molecules ; 24(19)2019 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-31554296

RESUMEN

Forty-five volatile organic compounds (VOCs) were identified or annotated in the mandibular gland reservoir content (MGRC) of the Southeast Asian ant Colobopsis explodens Laciny and Zettel, 2018 (Hymenoptera: Formicidae), using headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography mass spectrometry (GC-MS) and liquid extraction combined with GC-MS. In extension of previous reports on VOCs of C. explodens, members of different compound classes, such as alkanes, aliphatic and aromatic carboxylic acids, and phenolics, were detected. The ketone 2-heptanone and the biochemically related phenolics benzene-1,3,5-triol (phloroglucinol, PG), 1-(2,4,6-trihydroxyphenyl)ethanone (monoacetylphloroglucinol, MAPG), 5,7-dihydroxy-2-methylchromen-4-one (noreugenin), and 1-(3-Acetyl-2,4,6-trihydroxyphenyl)ethanone (2,4-diacetylphloroglucinol, DAPG) dominated the GC-MS chromatograms. The identities of the main phenolics MAPG and noreugenin were further verified by liquid chromatography-high resolution-tandem mass spectrometry (LC-HRMS/MS). A comparative study of MGRC samples originating from three distinct field expeditions revealed differences in the VOC profiles, but the presence and relative abundances of the dominating constituents were largely consistent in all samples. Our study considerably extends the knowledge about the number and type of VOCs occurring in the MGRC of C. explodens. Based on the type of the detected compounds, we propose that the likely irritant and antibiotic phenolic constituents play a role in defense against arthropod opponents or in protection against microbial pathogens.


Asunto(s)
Hormigas/química , Compuestos Orgánicos Volátiles/química , Compuestos Orgánicos Volátiles/aislamiento & purificación , Animales , Cromatografía Liquida , Cromatografía de Gases y Espectrometría de Masas , Metabolómica/métodos , Estructura Molecular , Microextracción en Fase Sólida
11.
Water Sci Technol ; 80(12): 2241-2249, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32245916

RESUMEN

Development of efficient and environmentally friendly methods to remove toxic pollutants from aqueous systems is a requirement to mitigate ever increasing environmental pollution problems. In this context, Artocarpus altilis (breadfruit) peel (BP), a waste material, can be used as a low-cost adsorbent for the removal of Pb(II) ions from synthetic pollutant solutions. The extent of removal of Pb(II), under optimized conditions in experimental batch experiments, is determined to be 82.0%, which is decreased in highly ionic environments, partly due to competition for a limited number of active adsorption sites, indicating the necessity of optimizing experimental parameters for the most efficient removal. Regression analysis and error function values evaluated for isotherm models associated with different adsorption mechanisms, namely Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, Redlich-Peterson and Sips, indicate that the best fitted model is the Sips followed by the Langmuir model with adsorption capacities (qmax) of 78.50 mg g-1 and 85.42 mg g-1, respectively. Thermodynamics arguments support the spontaneous and exothermic behavior of the Pb(II)-BP adsorption system, while adsorption kinetics of the system provides evidence for the applicability of the pseudo second order model with a rate constant of 0.504 g mg-1 min-1.


Asunto(s)
Artocarpus , Contaminantes Químicos del Agua , Adsorción , Contaminación Ambiental , Concentración de Iones de Hidrógeno , Cinética , Plomo , Termodinámica
12.
J Vis Exp ; (138)2018 08 26.
Artículo en Inglés | MEDLINE | ID: mdl-30199024

RESUMEN

The aim of this manuscript is to present a protocol describing the metabolomic analysis of Bornean 'exploding ants' belonging to the Colobopsis cylindrica (COCY) group. For this purpose, the model species C. explodens is used. Ants belonging to the minor worker caste possess distinctive hypertrophied mandibular glands (MGs). In territorial combat, they use the viscous contents of their enlarged mandibular gland reservoirs (MGRs) to kill rival arthropods in characteristic suicidal 'explosions' by voluntary rupture of the gastral integument (autothysis). We show the dissection of worker ants of this species for the isolation of the gastral portion of the wax-like MGR contents as well as listing the necessary steps required for solvent-extraction of the therein contained volatile compounds with subsequent gas chromatography-mass spectrometry (GC-MS) analysis and putative identification of metabolites contained in the extract. The dissection procedure is performed under cooled conditions and without the use of any dissection buffer solution to minimize the changes in the chemical composition of the MGR contents. After solvent-based extraction of volatile metabolites contained therein, the necessary steps for analyzing the samples via liquid-injection-GC-MS are presented. Lastly, data processing and putative metabolite identification with the use of the open-source software MetaboliteDetector is shown. With this approach, the profiling and identification of volatile metabolites in MGRs of ants belonging to the COCY group via GC-MS and the MetaboliteDetector software become possible.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/métodos , Metabolómica/métodos , Glándulas Salivales/metabolismo , Programas Informáticos , Animales , Hormigas , Volatilización
13.
Rev. biol. trop ; 66(3): 1090-1100, jul.-sep. 2018. tab, graf
Artículo en Inglés | LILACS, SaludCR | ID: biblio-977369

RESUMEN

Abstract Brunei is a small tropical country -located in Southeast Asia- for which there are no previous bibliometric studies. Here we analyze papers published by Brunei scientists from 1973 to 2016 in the Science Citation Index Expanded and compare results with other tropical countries. We identified 1 547 publications and 11 document types. The most productive categories were ecology, multidisciplinary geosciences, inorganic and nuclear chemistry, and environmental sciences. Singapore Medical Journal published most of these papers, and the three most productive institutions were Universiti Brunei Darussalam, RIPAS Hospital, and Universiti Teknologi Brunei. UK and Malaysia were the most frequent collaborating countries. M.A. Ali from the Universiti Brunei Darussalam was the most prolific author and a Brunei independent article written by C.K. Morley from the Universiti Brunei Darussalam in 2002 had the highest number of citations of the whole period and the highest number in 2016. The tropical countries of Central America and Asia have a few similarities but also important differences, and both are highly heterogeneous in scientific organization and productivity. Rev. Biol. Trop. 66(3): 1090-1100. Epub 2018 September 01.


Resumen Brunei es un pequeño país tropical del sudeste asiático, sobre el cual no hay estudios bibliométricos. Aquí analizamos los artículos publicados por científicos de Brunei de 1973 a 2016 y comparamos los resultados con otros países tropicales. Examinamos los documentos del Science Citation Index Expanded en la colección principal del Web of Science. Hallamos 1 547 publicaciones de Brunei con 11 tipos de documentos, donde las categorías más productivas fueron ecología, geociencias multidisciplinarias, química inorgánica y nuclear, y ciencias ambientales. Singapore Medical Journal publicó la mayoría, y las tres instituciones más productivas fueron: Universiti Brunei Darussalam, RIPAS Hospital y Universiti Teknologi Brunei. Reino Unido y Malasia fueron los países que más colaboraron con Brunei. M.A. Ali de la Universidad Brunei Darussalam fue el autor más prolífico. El mayor número total de citas, y el mayor número de citas en 2016, correspondieron a un artículo exclusivamente de Brunei, escrito por C. K. Morley de la Universiti Brunei Darussalam en 2002. Los países tropicales de América Central y Asia tienen algunas similitudes pero también diferencias importantes, siendo heterogéneos en su organización científica y productividad.


Asunto(s)
Investigadores , Brunei , Química Inorgánica/educación , Bibliometría , Ecología/educación , Dominios Científicos , Bibliometría , Ciencias de la Tierra/educación
14.
Zookeys ; (751): 1-40, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29706783

RESUMEN

A taxonomic description of all castes of Colobopsis explodens Laciny & Zettel, sp. n. from Borneo, Thailand, and Malaysia is provided, which serves as a model species for biological studies on "exploding ants" in Southeast Asia. The new species is a member of the Colobopsis cylindrica (COCY) group and falls into a species complex that has been repeatedly summarized under the name Colobopsis saundersi (Emery, 1889) (formerly Camponotus saundersi). The COCY species group is known under its vernacular name "exploding ants" for a unique behaviour: during territorial combat, workers of some species sacrifice themselves by rupturing their gaster and releasing sticky and irritant contents of their hypertrophied mandibular gland reservoirs to kill or repel rivals. This study includes first illustrations and morphometric characterizations of males of the COCY group: Colobopsis explodens Laciny & Zettel, sp. n. and Colobopsis badia (Smith, 1857). Characters of male genitalia and external morphology are compared with other selected taxa of Camponotini. Preliminary notes on the biology of C. explodens Laciny & Zettel, sp. n. are provided. To fix the species identity of the closely related C. badia, a lectotype from Singapore is designated. The following taxonomic changes within the C. saundersi complex are proposed: Colobopsis solenobia (Menozzi, 1926), syn. n. and Colobopsis trieterica (Menozzi, 1926), syn. n. are synonymized with Colobopsis corallina Roger, 1863, a common endemic species of the Philippines. Colobopsis saginata Stitz, 1925, stat. n., hitherto a subspecies of C. badia, is raised to species level.

15.
J Alzheimers Dis ; 61(2): 537-543, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29171995

RESUMEN

BACKGROUND: There is an increase in prevalence of young onset dementia (YOD). The specific problems among YOD patients and levels of caregiver burden (CB) in this group warrants further evaluation. OBJECTIVE: To evaluate and compare level of CB in YOD and late onset dementia (LOD). Also, we sought to understand the specific factors, such as neuropsychiatric symptoms, that may affect the levels of caregiver burden in the YOD group. METHODS: Patient-caregiver dyads with YOD and LOD were recruited from a tertiary neurology center. Levels of CB between YOD and LOD were compared among 183 patient-caregiver dyads. CB was quantified using the Zarit Burden Inventory (ZBI). Neuropsychological evaluations as well as the Neuropsychiatric Inventory were performed. Factors that influenced level of CB in YOD group was investigated with regression analyses. RESULTS: There were 57 YOD and 126 LOD dyads. Caregivers of YOD subjects reported significantly higher levels of burden compared to caregivers of LOD subjects (ZBI: 17.3 versus 13.94; p = 0.015). 52.6% of YOD caregivers reported a high caregiver burden. When compared to caregivers of LOD, the odds of a caregiver of YOD reporting high caregiver burden was 2.34 (95% CI: 1.22-4.49: p = 0.010). YOD dyads with a high caregiver burden had significantly higher neuropsychiatric inventory scores. Risk factors for high caregiver burden in YOD included family history of dementia and behavioral symptoms including disinhibited behavior, delusions, and apathy. CONCLUSION: Targeted support for caregivers of patients with YOD is needed to address the higher CB in this group.


Asunto(s)
Cuidadores/psicología , Costo de Enfermedad , Demencia/psicología , Adaptación Psicológica , Edad de Inicio , Anciano , Anciano de 80 o más Años , Síntomas Conductuales/etiología , Estudios Transversales , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Estrés Psicológico/etiología , Encuestas y Cuestionarios
16.
Int J Phytoremediation ; 20(5): 424-431, 2018 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-28862490

RESUMEN

This study investigated the potential of Azolla pinnata (AP) in the removal of toxic methyl violet 2B (MV) dye wastewater using the phytoextraction approach with the inclusion of an Artificial Neural Network (ANN) modelling. Parameters examined included the effects of dye concentration, pH and plant dosage. The highest removal efficiency was 93% which was achieved at a plant dosage of 0.8 g (dye volume = 200 mL, initial pH = 6.0, initial dye concentration = 10 mg L-1). A significant decrease in relative frond number (RFN), a growth rate estimator, observed at a dye concentration of 20 mg L-1 MV indicated some toxicity, which coincided with the plant pigments studies where the chlorophyll a content was lower than the control. There were little differences in the plant pigment contents between the control and those in the presence of dye (5 to 15 mg L-1) indicating the tolerance of AP to MV at lower concentrations. A three-layer ANN model was optimized (6 neurons in the hidden layer) and successfully predicted the phytoextraction of MV (R = 0.9989, RMSE = 0.0098). In conclusion, AP proved to be a suitable plant that could be used for the phytoextraction of MV while the ANN modelling has shown to be a reliable method for the modelling of phytoextraction of MV using AP.


Asunto(s)
Helechos , Biodegradación Ambiental , Clorofila A , Violeta de Genciana , Agua
18.
Ann Acad Med Singap ; 45(7): 273-83, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27523508

RESUMEN

INTRODUCTION: The purpose of the current study is to assess the psychometric properties of Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog) on patients with mild cognitive impairment (MCI) and mild Alzheimer's disease (AD) in a multicultural Asian context. MATERIALS AND METHODS: Sixty-four mild AD patients (mean age ± SD; 72.24 ± 7.88 years), 80 MCI patients (66.44 ± 7.45 years) and 125 healthy controls (HCs) (61.81 ± 6.96 years) participated in the study. Participants underwent a clinical interview and serial neuropsychological testing. ADAS-Cog total and subtest scores were compared across the 3 groups. Receiver operating characteristics (ROC) analysis were performed and sensitivity, specificity, positive predictive values (PPVs) and negative predictive values (NPVs) were calculated. RESULTS: Patients with MCI attained significantly worse neuropsychological test scores than healthy controls but significantly better results than patients with mild AD on ADAS-Cog total score, subtest items, and the delayed recall item (P <0.001). The best cutoff score to differentiate between MCI and HC was ≥4 (sensitivity = 0.73, specificity = 0.69, PPV = 0.90, NPV = 0.40), while the best cutoff score to distinguish between MCI and mild AD was ≥12 (sensitivity = 0.86, specificity = 0.89, PPV = 0.99, NPV = 0.32). Evidence of internal consistency of the ADAS-Cog (Cronbach α = 0.85) as well as convergent validity with the Mini-Mental State Examination (MMSE) (ρ = -0.75) and Montreal Cognitive Assessment (MoCA) (ρ = -0.81) (both P <0.001) was also found. CONCLUSION: The ADAS-Cog which is widely used in clinical trials is applicable to the Asian cohort. It is useful in the detection of MCI and mild AD as well as in distinguishing these 2 conditions.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Disfunción Cognitiva/diagnóstico , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/psicología , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Escala del Estado Mental , Persona de Mediana Edad , Pruebas Neuropsicológicas , Valor Predictivo de las Pruebas , Escalas de Valoración Psiquiátrica , Psicometría , Curva ROC , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Singapur
20.
Environ Monit Assess ; 188(2): 108, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26797814

RESUMEN

This study investigated the potential of untreated Azolla pinnata (AP) to remove toxic rhodamine B (RB) dye. The effects of adsorbent dosage, pH, ionic strength, contact time, and concentration were studied. Experiments involving the effects of pH and ionic strength indicated that hydrophobic-hydrophobic interactions might be the dominant force of attraction for the RB-AP adsorption system. The kinetics modelling of the kinetics experiment showed that pseudo-second-order best represented the adsorption process. The Weber-Morris intraparticle diffusion model showed that intraparticle diffusion is not the rate-limiting step, while the Boyd model suggested that film diffusion might be rate-limiting. The adsorption isotherm model, Langmuir, best represented the adsorption process, and the maximum adsorption capacity was predicted to be 72.2 and 199.7 mg g(-1) at 25 and 65 °C, respectively. Thermodynamics study indicates spontaneity, endothermic and physisorption-dominant adsorption process. The adsorbents were regenerated to satisfactory level with distilled water, HNO3 and NaOH. Pre-treatment of adsorbent with oxalic acid, citric acid, NaOH, HCl and phosphoric acid was investigated but the adsorption capacity was less than the untreated AP.


Asunto(s)
Helechos/química , Modelos Químicos , Rodaminas/análisis , Contaminantes Químicos del Agua/análisis , Adsorción , Difusión , Cinética , Termodinámica , Eliminación de Residuos Líquidos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA