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1.
Sci Rep ; 12(1): 6766, 2022 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-35474228

RESUMEN

In this work, polarization modulator utilizing MXene material, namely Nb2C is demonstrated. S band signal is injected into Nb2C thin film and is modulated by 1400 nm laser diode. A total of 39.81° of polarization rotation is attained when the pump power is increased to 223 mW. The rotation of light is due to thermo-optic effect. The efficiency of polarization modulator is calculated at 0.1974°/mW.

2.
Braz J Biol ; 82: e256277, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35352789

RESUMEN

The wax apple or jambu madu, is a non-climacteric tropical fruit from Myrtaceae family and widely cultivated in South East Asia. The limited availability of good quality seedlings of wax apple is the main problem to development of flourish it's market share in the current fruit industry. Therefore, in order to produce good quality planting materials, a study aimed at optimizing propagation and adventitious rooting technique and survivability of wax apple air layer was conducted. In this study, four different levels of Indole-3-Butyric Acid (IBA) concentration (0, 1000, 1500 and 2000 mg L-1) and three rooting media (sphagnum moss, vermicompost and garden soil) were applied after removal of bark (phloem) on the shoot to determine the effect on rooting and survivability of the wax apple air layer under field conditions. The results showed that the wax apple shoots treated with 2000 mg L-1 IBA produced the significantly higher number of roots, increased length of root, diameter of branch, length of branch, number of leaf and leaf area of air layers. In addition, the highest chlorophyll content and stomatal aperture were recorded in 2000 mg L-1 IBA treatment compared to other treatments including control. Vermicompost medium was better than garden soil and sphagnum moss in respect of rooting and survivability of air layers. The results showed that the combination of 2000 mg L-1 IBA and vermicompost as rooting media give the best combination to root initiation, root number, root length and survival rate (100%) of wax apple air layers. From this study, it can be concluded that 2000 mg L-1 IBA and vermicompost treatment enhance the root initiation, early establishment and survivability of wax apple air layered under field conditions.


Asunto(s)
Syzygium , Medios de Cultivo , Indoles/farmacología , Raíces de Plantas
3.
Braz. j. biol ; 82: e256277, 2022. tab, graf, ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1364494

RESUMEN

The wax apple or jambu madu, is a non-climacteric tropical fruit from Myrtaceae family and widely cultivated in South East Asia. The limited availability of good quality seedlings of wax apple is the main problem to development of flourish it's market share in the current fruit industry. Therefore, in order to produce good quality planting materials, a study aimed at optimizing propagation and adventitious rooting technique and survivability of wax apple air layer was conducted. In this study, four different levels of Indole-3-Butyric Acid (IBA) concentration (0, 1000, 1500 and 2000 mg L-1) and three rooting media (sphagnum moss, vermicompost and garden soil) were applied after removal of bark (phloem) on the shoot to determine the effect on rooting and survivability of the wax apple air layer under field conditions. The results showed that the wax apple shoots treated with 2000 mg L-1 IBA produced the significantly higher number of roots, increased length of root, diameter of branch, length of branch, number of leaf and leaf area of air layers. In addition, the highest chlorophyll content and stomatal aperture were recorded in 2000 mg L-1 IBA treatment compared to other treatments including control. Vermicompost medium was better than garden soil and sphagnum moss in respect of rooting and survivability of air layers. The results showed that the combination of 2000 mg L-1 IBA and vermicompost as rooting media give the best combination to root initiation, root number, root length and survival rate (100%) of wax apple air layers. From this study, it can be concluded that 2000 mg L-1 IBA and vermicompost treatment enhance the root initiation, early establishment and survivability of wax apple air layered under field conditions.


A maçã de cera, ou jambu madu, é uma fruta tropical não climatérica da família Myrtaceae e amplamente cultivada no Sudeste Asiático. A disponibilidade limitada de mudas de macieira de boa qualidade é o principal problema para o desenvolvimento de sua participação de mercado na fruticultura atual. Portanto, com o objetivo de produzir materiais de plantio de boa qualidade, foi realizado um estudo visando otimizar a técnica de propagação e enraizamento adventício e a sobrevivência da camada aérea da cera de macieira. Neste estudo, quatro diferentes níveis de concentração de ácido indol-3-butírico (AIB) (0, 1000, 1500 e 2000 mg L-1) e três meios de enraizamento (musgo esfagno, vermicomposto e solo de jardim) foram aplicados após a remoção da casca (floema) na parte aérea para determinar o efeito no enraizamento e capacidade de sobrevivência da camada de ar da macieira em condições de campo. Os resultados mostraram que os brotos de macieira tratados com 2000 mg L-1 de AIB produziram significativamente maior número de raízes, maior comprimento de raiz, diâmetro de galho, comprimento de galho, número de folhas e área foliar das camadas aéreas. Além disso, o maior teor de clorofila e abertura estomática foram registrados no tratamento 2000 mg L-1 IBA em comparação com outros tratamentos, incluindo o controle. O meio de vermicomposto foi melhor do que o solo de jardim e o musgo esfagno em relação ao enraizamento e capacidade de sobrevivência das camadas aéreas. Os resultados mostraram que a combinação de 2000 mg L-1 de AIB e vermicomposto como meio de enraizamento proporciona a melhor combinação para iniciação radicular, número de raízes, comprimento radicular e taxa de sobrevivência (100%) das camadas aéreas de macieira. A partir deste estudo, pode-se concluir que 2.000 mg L-1 de AIB e tratamento com vermicomposto melhoram a iniciação radicular, o estabelecimento precoce e a capacidade de sobrevivência de macieiras em camadas de ar em condições de campo.


Asunto(s)
24444 , Raíces de Plantas/crecimiento & desarrollo , Malus/crecimiento & desarrollo , Fertilizantes
4.
Sci Rep ; 11(1): 21278, 2021 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-34711908

RESUMEN

In this work, mode-locked thulium-doped fiber lasers operating in the 2 µm wavelength region were demonstrated using tantalum aluminum carbide (Ta2AlC)-based saturable absorbers (SAs) utilizing the evanescent wave interaction. The Ta2AlC MAX Phase was prepared by dissolving the Ta2AlC powder in isopropyl alcohol and then deposited onto three different evanescent field-based devices, which were the tapered fiber, side-polished fiber, and arc-shaped fiber. Flame-brushing and wheel-polishing techniques were used to fabricate the tapered and arc-shaped fibers, respectively, while the side-polished fiber was purchased commercially. All three SA devices generated stable mode-locked pulses at center wavelengths of 1937, 1931, and 1929 nm for the tapered, side-polished, and arc-shaped fibers. The frequency of the mode-locked pulses was 10.73 MHz for the tapered fiber, 9.58 MHz for the side-polished fiber, and 10.16 MHz for the arc-shaped fiber. The measured pulse widths were 1.678, 1.734, and 1.817 ps for each of the three SA devices. The long-term stability of the mode-locked lasers was tested for each configuration over a 2-h duration. The lasers also showed little to no fluctuations in the center wavelengths and the peak optical intensities, demonstrating a reliable, ultrafast laser system.

5.
Trop Biomed ; 38(3): 387-395, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34608112

RESUMEN

This study was carried out in order to identify acanthocephalan species complexes, based on morphological variability, infecting Barbonymus schwanenfeldii from Lake Kenyir, Terengganu, Malaysia. Acanthocephala were fixed in ethanol, stained with aceto-carmine and studied morphologically by using a light microscope. Variation in morphological traits such as proboscis, proboscis receptacle, egg, testes shape and location, number of hooks and cement gland has been traditionally used to diagnose the acanthocephalans species but the delimitations between closely related species are still confusing and are always questionable among taxonomists. Molecular analysis was used for support the identification. Morphological variability prospecting reveals the presence of three different new species complexes from the subgenus Acanthosentis by referring published taxonomic keys. These new species may be distinguished from the other 46 described species of Acanthosentis by having six unique structures: the presence of an anterior parareceptacle structure (PRS); vaginal sleeve structure; a paired lateral, cone-shaped, muscular jacket surrounding the vagina; alternating pattern and size of proboscis hooks, variation in proboscis size and shape; the presence of the circular collar ring around the neck between the proboscis and trunk and lastly the presence of a muscular-like structure attached to the collar ring on the proboscis. These acanthocephalans found in the intestine of B. schwanenfeldii in Kenyir Lake Malaysia represent new species, named Acanthogyrus ( Acanthosentis) kenyirensis n.sp., A. ( A.) terengganuensis n.sp. and A. ( A.) tembatensis n. sp.


Asunto(s)
Acantocéfalos , Cyprinidae , Enfermedades de los Peces , Helmintiasis Animal , Acantocéfalos/anatomía & histología , Acantocéfalos/clasificación , Animales , Cyprinidae/parasitología , Femenino , Enfermedades de los Peces/parasitología , Lagos , Malasia
6.
Sci Rep ; 11(1): 11652, 2021 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-34078979

RESUMEN

As a result of the emergence of two-dimensional (2D) materials for various opto-electronics applications, a new class of materials named MXenes have been attracting interests due to their outstanding nonlinear properties. In this work, an MXene niobium carbide (Nb2C) was proposed and demonstrated as a saturable absorber to induce mode-locking in thulium- and thulium/holmium-doped fiber lasers. The Nb2C solution was first prepared using the liquid exfoliation technique, and then deposited onto a microfiber for integration into the laser cavity. Stable mode-locking operation was observed in both laser cavities, where the center wavelengths of the laser were recorded at 1944 nm for the TDFL and 1950 nm for the THDFL. The generated pulses in the TDFL and THDFL had repetition rates of 9.35 and 11.76 MHz respectively, while their corresponding pulse widths were 1.67 and 1.34 ps. Both of the lasers were highly stable, having SNR values of more than 52 dB and showed no major fluctuations when tested for their long-term stabilities. The results demonstrate an excellent performance of the Nb2C as a saturable absorber, offering opportunities to further explore MXenes for future photonics devices.

7.
Med J Malaysia ; 76(3): 438-440, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-34031350

RESUMEN

Venous thrombosis is a potentially life-threatening condition with varied aetiology. First described in 1912 as a complication of peritonsillar abscess, internal jugular vein (IJV) thrombosis is a rare entity in children with very few cases reported until now. Among the leading causes of this condition are prolonged use of IJV for venous access and central venous catheterisation, acute mastoiditis and Lemierre's syndrome.1 IJV thrombosis can also occur as a complication of head and neck infections, but rarely appears as its first presentation. The clinical manifestations are often vague and ambiguous, thus requiring a high index of suspicion to diagnose IJV thrombosis. We describe here a case of internal jugular vein thrombosis (IJVT) and the management of this rare condition in an otherwise healthy 8- year-old boy. The patient was investigated thoroughly to rule out possible pathological causes of IJV thrombosis and managed holistically with a multidisciplinary team approach. Although the occurrence is rare, it should be recognised as a complication of deep neck infections in order to initiate prompt and accurate therapy.


Asunto(s)
Venas Yugulares , Trombosis de la Vena , Niño , Humanos , Venas Yugulares/diagnóstico por imagen , Masculino , Cuello , Síndrome , Trombosis de la Vena/diagnóstico por imagen , Trombosis de la Vena/etiología
8.
Tropical Biomedicine ; : 387-395, 2021.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-906542

RESUMEN

@#This study was carried out in order to identify acanthocephalan species complexes, based on morphological variability, infecting Barbonymus schwanenfeldii from Lake Kenyir, Terengganu, Malaysia. Acanthocephala were fixed in ethanol, stained with aceto-carmine and studied morphologically by using a light microscope. Variation in morphological traits such as proboscis, proboscis receptacle, egg, testes shape and location, number of hooks and cement gland has been traditionally used to diagnose the acanthocephalans species but the delimitations between closely related species are still confusing and are always questionable among taxonomists. Molecular analysis was used for support the identification. Morphological variability prospecting reveals the presence of three different new species complexes from the subgenus Acanthosentis by referring published taxonomic keys. These new species may be distinguished from the other 46 described species of Acanthosentis by having six unique structures: the presence of an anterior parareceptacle structure (PRS); vaginal sleeve structure; a paired lateral, cone-shaped, muscular jacket surrounding the vagina; alternating pattern and size of proboscis hooks, variation in proboscis size and shape; the presence of the circular collar ring around the neck between the proboscis and trunk and lastly the presence of a muscular-like structure attached to the collar ring on the proboscis. These acanthocephalans found in the intestine of B. schwanenfeldii in Kenyir Lake Malaysia represent new species, named Acanthogyrus (Acanthosentis) kenyirensis n.sp., A. (A.) terengganuensis n.sp. and A. (A.) tembatensis n. sp.

9.
Sci Rep ; 10(1): 9233, 2020 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-32514045

RESUMEN

A MAX phase Ti3AlC2 thin film is demonstrated as a saturable absorber (SA) to induce Q-switching in the 2.0 µm region. The Ti3AlC2 thin film is sandwiched between two fiber ferrules and integrated into thulium doped fiber laser (TDFL) and thulium-holmium doped fiber laser (THDFL) cavities. Stable Q-switched pulses are observed at 1980.79 nm and 1959.3 nm in the TDFL and THDFL cavities respectively, with repetition rates of 32.57 kHz and 21.94 kHz and corresponding pulse widths of 2.72 µs and 3.9 µs for both cavities. The performance of the Ti3AlC2 based SA for Q-switching operation indicates the high potential of other MAX phase materials to serve as SAs in future photonics systems.

10.
Benef Microbes ; 10(4): 355-373, 2019 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-30882244

RESUMEN

Probiotics have been reported to exert beneficial effects along the gut-brain axis. This randomised, double-blind and placebo-controlled human study aimed to evaluate such properties of Lactobacillus plantarum DR7 and its accompanying mechanisms in stressed adults. One hundred and eleven (n=111; DR7 n=56, placebo n=55) stressed adults were recruited based on moderate stress levels using the PSS-10 questionnaire. The consumption of DR7 (1×109 cfu/day) for 12 weeks reduced symptoms of stress (P=0.024), anxiety (P=0.001), and total psychological scores (P=0.022) as early as 8 weeks among stressed adults compared to the placebo group as assessed by the DASS-42 questionnaire. Plasma cortisol level was reduced among DR7 subjects as compared to the placebo, accompanied by reduced plasma pro-inflammatory cytokines, such as interferon-γ and transforming growth factor-α and increased plasma anti-inflammatory cytokines, such as interleukin 10 (P<0.05). DR7 better improved cognitive and memory functions in normal adults (>30 years old), such as basic attention, emotional cognition, and associate learning (P<0.05), as compared to the placebo and young adults (<30 years old). The administration of DR7 enhanced the serotonin pathway, as observed by lowered expressions of plasma dopamine ß-hydroxylase (DBH), tyrosine hydroxylase (TH), indoleamine 2,3-dioxygenase and tryptophan 2,3-dioxygenase accompanied by increased expressions of tryptophan hydroxylase-2 and 5-hydroxytryptamine receptor-6, while stabilising the dopamine pathway as observed via stabilised expressions of TH and DBH over 12 weeks as compared to the placebo (P<0.05). Our results indicated that DR7 fulfil the requirement of a probiotic strain as per recommendation of FAO/WHO and could be applicable as a natural strategy to improve psychological functions, cognitive health and memory in stressed adults.


Asunto(s)
Ansiedad/prevención & control , Lactobacillus plantarum/fisiología , Probióticos/administración & dosificación , Estrés Psicológico/terapia , Adulto , Ansiedad/microbiología , Ansiedad/psicología , Cognición/fisiología , Citocinas/sangre , Método Doble Ciego , Humanos , Hidrocortisona/sangre , Memoria/fisiología , Persona de Mediana Edad , Neurotransmisores/sangre , Serotonina/sangre , Estrés Psicológico/microbiología , Estrés Psicológico/psicología , Resultado del Tratamiento , Adulto Joven
11.
Malays J Pathol ; 41(3): 351-354, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31901921

RESUMEN

INTRODUCTION: Neisseria meningitidis infections often cause severe meningitis as well as bacteraemia. However, cellulitis in meningococcal diseases have rarely been described. Here, we report a case of right lower limb cellulitis caused by N. meningitidis. CASE REPORT: A 69-year-old woman presented with fever and lower limb swelling. She had diabetes mellitus, hypertension, dyslipidaemia and a history of surgical resection of vulvar carcinoma. N. meningitidis was isolated from her blood culture. DISCUSSION: This report provides additional evidence in support of N. meningitidis as a cause of cellulitis.


Asunto(s)
Celulitis (Flemón)/patología , Infecciones Meningocócicas/patología , Neisseria meningitidis/patogenicidad , Anciano , Celulitis (Flemón)/diagnóstico , Femenino , Humanos , Extremidad Inferior/microbiología , Extremidad Inferior/patología , Infecciones Meningocócicas/diagnóstico
12.
J Clin Pharm Ther ; 43(1): 80-86, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28656735

RESUMEN

WHAT IS KNOWN: Drug addiction is a novelty-seeking personality trait that is associated with the candidate genes OPRD1 (opioid delta receptors), OPRK1 (opioid kappa receptors) and PDYN (prodynorphin). However, associations between single nucleotide polymorphisms (SNPs) rs1042114 (80G>T) of the OPRD1 gene, rs702764 (843 A>G) of the OPRK1 gene, and rs910080 (3' UTR _743T>C), rs1997794 (5' UTR -381A>G) and rs1022563 (3' UTR) of the PDYN gene and novelty seeking remain controversial as reported results have not been reproducible. OBJECTIVE: The goal of this study was to determine the frequencies of SNPs rs1042114, rs702764, rs1997794, rs1022563 and rs910080 in the Malaysian population and to study their association with opioid dependence in Malaysian Malays. METHODS: A total of 459 Malay male with opioid dependence and 543 healthy male (controls) subjects were included in this study. SNPs were genotyped using the TaqMan SNP genotyping assay. Statistical analysis was performed using Golden Helix SVS software suite to identify the distribution of allele and genotype frequencies, and SNP-SNP interactions were also analysed in this study. RESULTS AND DISCUSSION: SNP rs1042114 in the OPRD1 gene is strongly associated with opiate addiction (P=.0001). In individuals homozygous for this risk allele, the likelihood of opiate addiction is increased by a factor 1.62 (95% confidence interval (CI) 1.412-1.875). Polymorphic alleles at SNP rs702764 of OPRK1 were not associated with opioid dependence. A significant association between opioid dependence and SNP rs910080 of PDYN (P=.0217) was detected, but there was no association for SNPs rs199774 and rs1022563. A significant interaction was also identified between homozygous wild-type genotype TT of rs702764 with the risk genotypes TG/GG of rs1042114 (odds ratio (OR)=2.111 (95% CI 1.227-3.631), P=.0069) and with the risk genotypes GA/AA of rs910080 (OR=1.415 (95% CI 1.04-1.912), P=.0239). WHAT IS NEW AND CONCLUSION: The results indicate that SNPs rs1042114 and rs910080 contribute to vulnerability to opioid dependence in the Malaysian Malay population. These results will help us to understand the effect of the SNPs and the SNP-SNP interaction on opioid dependence and may assist in efforts to screen vulnerable individuals and match them with individually tailored prevention and treatment strategies.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Trastornos Relacionados con Opioides/genética , Polimorfismo de Nucleótido Simple/genética , Receptores Opioides delta/genética , Receptores Opioides kappa/genética , Adulto , Alelos , Frecuencia de los Genes/genética , Genotipo , Humanos , Masculino
13.
Public Health Action ; 7(2): 155-160, 2017 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-28695090

RESUMEN

Setting: Needle and Syringe Exchange Programme (NSEP) implemented by non-governmental organisations in Malaysia. Objectives: To determine enrolment, characteristics and retention in the NSEP of people who inject drugs (PWID) between 2013 and 2015. Design: Retrospective cohort study. Results: There were 20 946 PWID, with a mean age of 38 years. The majority were male (98%) and of Malay ethnicity (92%). Follow-up data were available for 20 761 PWID. Annual retention of newly enrolled PWID for each year was respectively 85%, 87% and 78% for 2013, 2014 and 2015, although annual enrolment over these years declined from 10 724 to 6288 to 3749. Total person-years (py) of follow-up were 27 806, with loss to follow-up of 40 per 100 py. Cumulative probability of retention in NSEP was 66% at 12 months, 45% at 24 months and 26% at 36 months. Significantly higher loss to follow-up rates were observed in those aged 15-24 years or ⩾50 years, females, transgender people and non-Malay ethnic groups. Conclusion: Annual retention of new PWID on NSEP was impressive, although enrolment declined over the 3 years of the study and cumulative loss to follow-up was high. A better understanding of these programmatic outcomes is required.


Contexte: Programme d'échange d'aiguilles et de seringues (NSEP) mis en œuvre par des organisations non-gouvernementales en Malaysie.Objectif: Déterminer l'enrôlement, les caractéristiques et la rétention dans le NSEP des personnes qui s'injectent des drogues (PWID) entre 2013 et 2015.Schéma: Etude rétrospective de cohorte.Résultats: Il y a eu 20 946 PWID, dont l'âge moyen a été de 38 ans. La majorité a été de sexe masculin (98%) et d'ethnie malaise (92%). Les données de suivi ont été disponibles pour 20 761 PWID. Le taux de rétention annuel des PWID nouvellement enrôlés a été de 85%, 87% et 78% pour 2013, 2014 et 2015, respectivement, bien que l'enrôlement annuel ait décliné de 10 724 à 6288, puis à 3749. Le suivi total en personnes-années (py) a été de 27 806, avec des pertes de vue de 40 pour 100 py. La probabilité cumulative de rétention dans le NSEP a été de 66% à 12 mois, de 45% à 24 mois et de 26% à 36 mois. Des taux de perdus de vue significativement plus élevés sont survenus chez les patients âgés de 15 à 24 ans ou ⩾50 ans, de sexe féminin, transgenre et d'un groupe ethnique autre que malais.Conclusion: La rétention annuelle des nouveaux PWID dans la NSEP a été impressionnante, bien que l'enrôlement ait décliné sur les 3 ans de l'étude et que les pertes de vue cumulées aient été élevées. Une meilleure compréhension de ces résultats du programme est requise.


Marco de referencia: El programa nacional de intercambio de agujas y jeringuillas introducido (NSEP) por organizaciones no gubernamentales en Malasia.Objetivos: Describir la inscripción, la permanencia y las características de las personas consumidoras de drogas inyectables (PWID) que participaron en el programa NSEP entre el 2013 y el 2015.Método: Fue este une estudio retrospectivo de cohortes.Resultados: Se inscribieron en el programa 20 946 PWID, cuya edad promedio fue 38 años. La mayoría era de sexo masculino (98%) y de etnia malaya (92%). Se practicó el seguimiento de 20 761 personas. La tasa anual de permanencia en el programa de los recién inscritos fue 85% en el 2013, 87% en el 2014 y 78% en el 2015, pero la tasa inscripción anual disminuyó de 10 724 a 6288 y 3749 personas, respectivamente. Se logró un seguimiento total de 27 806 años-persona (py), con una pérdida durante el seguimiento de 40 por 100 py. La probabilidad acumulada de permanencia en el programa fue 66% a los 12 meses, 45% a los 24 meses y 26% a los 36 meses. Las pérdidas durante el seguimiento fueron significativamente mayores en el grupo de 15 a 24 años de edad o a partir de los 50 años, en las mujeres, las personas transgénero y los grupos étnicos diferentes al malayo.Conclusión: La tasa anual de retención de las PWID recién inscritas en el programa NSEP fue sorprendente, pese a que las inscripciones disminuyeron durante los 3 años y las pérdidas acumuladas durante el seguimiento fueron altas. Es necesario ampliar la comprensión de estos resultados programáticos.

14.
Infect Genet Evol ; 34: 153-9, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26047685

RESUMEN

Southeast Asian Ovalocytosis (SAO) is a common red blood cell disorder that is maintained as a balanced polymorphism in human populations. In individuals heterozygous for the SAO-causing mutation there are minimal detrimental effects and well-documented protection from severe malaria caused by Plasmodium vivax and Plasmodium falciparum; however, the SAO-causing mutation is fully lethal in utero when homozygous. The present-day high frequency of SAO in Island Southeast Asia indicates the trait is maintained by strong heterozygote advantage. Our study elucidates the evolutionary origin of SAO by characterizing DNA sequence variation in a 9.5 kilobase region surrounding the causal mutation in the SLC4A1 gene. We find substantial haplotype diversity among SAO chromosomes and estimate the age of the trait to be approximately 10,005 years (95% CI: 4930-23,200 years). This date is far older than any other human malaria-resistance trait examined previously in Southeast Asia, and considerably pre-dates the widespread adoption of agriculture associated with the spread of speakers of Austronesian languages some 4000 years ago. Using a genealogy-based method we find no evidence of historical positive selection acting on SAO (s=0.0, 95% CI: 0.0-0.03), in sharp contrast to the strong present-day selection coefficient (e.g., 0.09) estimated from the frequency of this recessively lethal trait. This discrepancy may be due to a recent increase in malaria-driven selection pressure following the spread of agriculture, with SAO targeted as a standing variant by positive selection in malarial populations.


Asunto(s)
Proteína 1 de Intercambio de Anión de Eritrocito/genética , Eliptocitosis Hereditaria/genética , Malaria/genética , Asia Sudoriental , Evolución Molecular , Femenino , Frecuencia de los Genes , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Haplotipos , Humanos , Desequilibrio de Ligamiento , Masculino , Polimorfismo de Nucleótido Simple , Selección Genética , Análisis de Secuencia de ADN
15.
Bioresour Technol ; 192: 212-8, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26038325

RESUMEN

The objective of this study is to extract and characterize lignin from oil palm biomass (OPB) by dissolution in 1-butyl-3-methylimidazolium chloride ([bmim][Cl]), followed by the lignin extraction through the CO2 gas purging prior to addition of aluminum potassium sulfate dodecahydrate (AlK(SO4)2 · 12H2O). The lignin yield, Y(L) (%wt.) was found to be dependent of the types of OPB observed for all precipitation methods used. The lignin recovery, RL (%wt.) obtained from CO2-AlK(SO4)2 · 12H2O precipitation was, however dependent on the types of OPB, which contradicted to that of the acidified H2SO4 and HCl solutions of pH 0.7 and 2 precipitations. Only about 54% of lignin was recovered from the OPB. The FTIR results indicate that the monodispersed lignin was successfully extracted from the OPT, OPF and OPEFB having a molecular weight (MW) of 1331, 1263 and 1473 g/mol, and degradation temperature of 215, 207.5 and 272 °C, respectively.


Asunto(s)
Compuestos de Alumbre/química , Líquidos Iónicos/química , Lignina/química , Aceites de Plantas/química , Biomasa , Dióxido de Carbono/química , Precipitación Química , Concentración de Iones de Hidrógeno , Imidazoles/química , Iones/química , Aceite de Palma , Solubilidad , Soluciones/química
16.
Child Care Health Dev ; 41(2): 213-21, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25219320

RESUMEN

BACKGROUND: Visual-motor integration (VMI) is important in children's development because it is associated with the performance of many functional skills. Deficits in VMI have been linked to difficulties in academic performance and functional tasks. Clinical assessment experience of occupational therapists in Singapore suggested that there is a potential difference between the VMI performance of Singaporean and American children. Cross-cultural studies also implied that culture has an influence on a child's VMI performance, as it shapes the activities that a child participates in. The purpose of this study was to (1) explore if there was a difference between the VMI performance of Singaporean and American preschoolers, and (2) determine if there were ethnic differences in the VMI performance of Singaporean preschoolers. METHODS: The Beery-VMI, which was standardized in America, is commonly used by occupational therapists in Singapore to assess the VMI ability of children. We administered the Beery-VMI (fifth edition) full form test (excluding the supplemental tests) to 385 preschoolers (mean age = 63.3 months) from randomly selected schools in Singapore. We compared the scores of Singaporean preschoolers with those of the American standardization norms using the one-sample t-test. Scores of different ethnic groups among the Singapore population were also compared using a one-way anova, followed by the Bonferroni post-hoc test. RESULTS: Singaporean preschoolers and the standardization sample of American children performed significantly differently in all age groups (P < 0.05). Among the Singapore population, the scores were also significantly different (P < 0.05) between the (i) Chinese and Malay and (ii) Chinese and Indians ethnic groups. CONCLUSION: Preschoolers from different cultural and ethnic groups had different VMI performance. Certain cultural beliefs and practices may affect VMI performance. Clinicians should exercise caution when using an assessment in communities and cultures outside the ones on which it was standardized.


Asunto(s)
Desarrollo Infantil/fisiología , Etnicidad/psicología , Desempeño Psicomotor/fisiología , Percepción Visual/fisiología , Pueblo Asiatico/psicología , Preescolar , Comparación Transcultural , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Singapur , Estados Unidos , Población Blanca/psicología
17.
J Aerosol Med Pulm Drug Deliv ; 27(1): 30-4, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23409833

RESUMEN

BACKGROUND: Cell-based therapy has great potential to treat patients with lung diseases. The administration of cells into an injured lung is one method of repairing and replacing lost lung tissue. However, different types of delivery have been studied and compared, and none of the techniques resulted in engraftment of a high number of cells into the targeted organ. In this in vitro study, a novel method of cell delivery was introduced to investigate the possibility of delivering aerosolized skin-derived fibroblasts. METHODS: Skin-derived fibroblasts were trypsinized and resuspended in growth medium. A syringe filled with cells (10(5) cells/mL) was attached to MicroSprayer(®) Aerosolizer, a device that can modify a liquid into an aerosol. The tip of the MicroSprayer Aerosolizer was channeled into a T25 flask containing growth medium. Survivability following aerosolization was observed on a daily basis. HeLa cells were used for comparison. The same aerosolization and culture methods were used to treat HeLa cells. RESULTS: One day following aerosolization, skin-derived fibroblasts showed no sign of vacuolation due to cell stress. They attached to the surface of the flask, indicating that most of them survived aerosolization. The surviving cells were also able to proliferate rapidly, forming a confluent monolayer of cells at day 4. In contrast, HeLa cells were unable to proliferate even after 21 days of culture. CONCLUSIONS: This study provides the first evidence that cells can be aerosolized without the risk of low cell survivability and stress. The high survival rate of fibroblast cells following aerosolization illustrates the potential for delivering of such cells in future aerosol cell-based therapy to treat lung diseases.


Asunto(s)
Proliferación Celular , Tratamiento Basado en Trasplante de Células y Tejidos/métodos , Fibroblastos/trasplante , Enfermedades Pulmonares/terapia , Pulmón/fisiopatología , Regeneración , Aerosoles , Animales , Supervivencia Celular , Células HeLa , Humanos , Pulmón/patología , Enfermedades Pulmonares/patología , Enfermedades Pulmonares/fisiopatología , Conejos , Estrés Mecánico , Factores de Tiempo
18.
Singapore Med J ; 53(1): 36-9, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22252181

RESUMEN

INTRODUCTION: The Breast Module (BR23) is increasingly being used worldwide in breast cancer research. This study evaluates the appropriateness of the translated version (i.e. BR23-Malay version) as a useful tool for the Malaysian population who could understand Malay, and examines the reliability and validity of the BR23-Malay version. METHODS: This was a prospective study involving 68 Malaysian women who could understand Malay very well. They answered the BR23-Malay version at two evaluation points--three and ten weeks following surgery for breast cancer. Internal consistency, test-retest intraclass correlation coefficients (ICC), effect size index, sensitivity and discriminity of the scale were calculated. RESULTS: Internal consistencies were acceptable for the functional domains (0.87 for body image; 0.84 for sexual functioning) and symptomatology domains (0.82 for systemic therapy side effect; 0.82 for breast symptoms; 0.70 for arm symptoms). Test-retest ICC ranged from 0.26 to 1.00. Sensitivity of the scale was observed in all domains except sexual functioning. CONCLUSION: The Malay version of BR23 is a suitable tool to measure the functional and symptomatology domains of women diagnosed with breast cancer.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Adulto , Neoplasias de la Mama/cirugía , Femenino , Humanos , Lenguaje , Malasia , Oncología Médica/métodos , Oncología Médica/normas , Persona de Mediana Edad , Estudios Prospectivos , Psicometría/métodos , Calidad de Vida , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
19.
Med J Malaysia ; 65(1): 41-4, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21265247

RESUMEN

This paper validates the Brief COPE Scale in Malaysian women with breast cancer. Test-retest evaluation was undertaken at two/three weeks and ten weeks following surgery. Internal consistencies ranged from 0.25 to 1.00. Meanwhile, the Intraclass Correlation Coefficient (ICC) ranged from 0.05 to 1.00. Sensitivity of the scale was indicated by the mean differences as observed in most of the domains with Effect Size Index (ESI) ranged from 0 to 0.53. Significant differences between mastectomy and lumpectomy were observed for Active coping, Planning and Acceptance. Brief COPE Scale showed fairly good reliability and validity.


Asunto(s)
Adaptación Psicológica , Neoplasias de la Mama/psicología , Adulto , Neoplasias de la Mama/tratamiento farmacológico , Quimioterapia Adyuvante , Femenino , Humanos , Malasia , Persona de Mediana Edad , Reproducibilidad de los Resultados
20.
Auton Neurosci ; 148(1-2): 50-4, 2009 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-19349212

RESUMEN

The aim of the present study was to determine if paraventricular-spinal vasopressin neurones participate in the sympatho-inhibitory effects of systemically administered atrial natriuretic peptide (ANP) on renal sympathetic nerve activity (RSNA). Experiments were carried out on male Sprague-Dawley rats anesthetized with 1.3 g/kg urethane. Changes in mean arterial pressure (mm Hg), heart rate (beats per minute) and RSNA (%) were measured following intravenous bolus administration of ANP (250 ng, 500 ng and 5 microg). Intrathecal application of selective V 1a receptor antagonist was performed to test for the involvement of supraspinal vasopressin pathways in mediating the effect on sympathetic outflow evoked by intravenous ANP administration. The results obtained demonstrated that both low and high doses of ANP caused renal sympathoinhibition (250 ng; - 7.5 +/- 1%, 500 ng; - 14.2 +/- 1%, 5 microg; - 16.4 +/- 2%), concomitant with vasodilation and bradycardia. After spinal vasopressin receptor blockade, the inhibitory effects of ANP were prevented and there was a small renal sympatho-excitation (250 ng; + 1.7 +/- 0.2%, 500 ng; + 6.1 +/- 0.03%, 5 microg; + 8.0 +/- 0.03%, P < 0.05). Therefore, the renal sympathetic nerve inhibition elicited by circulating ANP is dependent on the efficacy of a well established supraspinal vasopressin pathway. Since supraspinal vasopressin neurones without exception excite renal sympathetic neurones, it is suggested that ANP elicits this effect by activating cardiac vagal afferents that inhibit the spinally projecting vasopressin neurones at their origin in the paraventricular nucleus of the hypothalamus.


Asunto(s)
Factor Natriurético Atrial/farmacología , Neuronas/fisiología , Médula Espinal/citología , Sistema Nervioso Simpático/efectos de los fármacos , Vasopresinas/metabolismo , Potenciales de Acción/efectos de los fármacos , Potenciales de Acción/fisiología , Análisis de Varianza , Animales , Antagonistas de los Receptores de Hormonas Antidiuréticas , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/fisiología , Relación Dosis-Respuesta a Droga , Frecuencia Cardíaca/efectos de los fármacos , Frecuencia Cardíaca/fisiología , Riñón/inervación , Masculino , Neuronas/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Sistema Nervioso Simpático/fisiología
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