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2.
J Phys Chem B ; 124(18): 3678-3685, 2020 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-32275422

RESUMO

Herein, we detail an atomic-level investigation of the cutinase enzyme encapsulated within a model metal-organic framework (MOF) platform using quantum mechanics calculations and molecular dynamics simulations. Cutinase, when encapsulated in an isoreticularly expanded MOF-74 (cutinase@IRMOF-74-VI), was proven to maintain its structural stability at temperatures that would otherwise denature the enzyme in its unprotected native state. Hydrogen bonding and salt bridge interactions, most notably involving arginine residues at the surface of the enzyme, were critical for stabilizing cutinase within the pore channels of IRMOF-74-VI. The findings reported support the viability of enzyme encapsulation in a porous material by demonstrating that a model enzyme not only retains its structural integrity but also remains accessible and active under extreme and foreign conditions.


Assuntos
Estruturas Metalorgânicas , Ligação de Hidrogênio , Simulação de Dinâmica Molecular
3.
Appl Opt ; 56(21): 5865-5870, 2017 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-29047907

RESUMO

A compact all-fiber multimode interferometer (MMI) designed to produce a switchable multi-wavelength thulium-doped fiber laser (TDFL) is proposed and demonstrated. The TDFL fiber ring cavity employs a 60-cm-long multimode fiber into the cavity to induce multimode interference and provide intensity-dependent loss in order to generate a multi-wavelength output. The suppression of mode competition and the overall stability of the TDFL are further improved by exploiting the filtering capability of a Sagnac loop. By increasing the pump power, a switchable wavelength output is allowed with a wavelength spacing of ∼1.8 nm. At 361 mW input pump power, nine laser lines are generated, with a maximum signal-to-noise ratio value of ∼36 dB and an output power of 3.3 mW. The multi-wavelength TDFL also exhibits great stability in one-hour operation with a wavelength drift of 0.2 nm. The proposed multi-wavelength TDFL has potential to be employed in future thulium-doped fiber amplifier-based telecommunication infrastructure and also may be applicable in areas such as sensing and spectroscopy, largely associated with its 2 µm wavelength output.

4.
Ir Med J ; 110(6): 579, 2017 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-28952669

RESUMO

Psychological distress is common in patients with cancer and psychological well-being is increasingly seen as an important component of cancer care. The aim of this study was to examine the relationship between cancer type and subjective distress. The following data were collected from a database of consecutive psycho-oncology referrals to the Liaison Psychiatry service in Cork University Hospital from 2006 to 2015: demographics, cancer diagnosis, Distress Thermometer (DT) score. 2102 out of 2384 referrals were assessed. Of those assessed, the most common cancer diagnoses were breast (23%, n=486) followed by haematological (21%, n=445). There were significant difference in DT score between the different cancer types, (?2(13)=33.685, p=0.001, Kruskal-Wallis test). When adjusted for age, gender and whether or not the cancer was recently diagnosed, there was no significant association between cancer type and psychological distress. In conclusion, cancer type is not associated with level of distress in cancer.


Assuntos
Neoplasias/psicologia , Psico-Oncologia , Encaminhamento e Consulta , Estresse Psicológico/psicologia , Neoplasias da Mama/psicologia , Feminino , Neoplasias Hematológicas/psicologia , Humanos , Neoplasias/classificação , Estatísticas não Paramétricas
5.
Sci Rep ; 7(1): 10714, 2017 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-28878369

RESUMO

Peroxisome proliferator-activated receptor gamma (PPARγ) is a nuclear receptor that is deregulated in obesity. PPARγ exerts diverse antineoplastic effects. Attempting to determine the clinical relevance of the epigenetic mechanisms controlling the expression PPARγ and susceptibility to colorectal cancer (CRC) in obese subjects, this study investigated the role of some microRNAs and DNA methylation on the deregulation of PPARγ. Seventy CRC patients (34 obese and 36 lean), 22 obese and 24 lean healthy controls were included. MicroRNA levels were measured in serum. PPARγ promoter methylation was evaluated in peripheral blood mononuclear cells (PBMC). PPARγ level was evaluated by measuring mRNA level in PBMC and protein level in serum. The tested microRNAs (miR-27b, 130b and 138) were significantly upregulated in obese and CRC patients. Obese and CRC patients had significantly low levels of PPARγ. A significant negative correlation was found between PPARγ levels and the studied microRNAs. There was a significant PPARγ promoter hypermethylation in CRC patients that correlated to low PPARγ levels. Our results suggest that upregulation of microRNAs 27b, 130b and 138 is associated with susceptibility to CRC in obese subjects through PPARγ downregulation. Hypermethylation of PPARγ gene promoter is associated with CRC through suppression of PPARγ regardless of BMI.


Assuntos
Neoplasias Colorretais/genética , Epigênese Genética , Regulação da Expressão Gênica , Obesidade/genética , PPAR gama/genética , Estudos de Casos e Controles , MicroRNA Circulante , Neoplasias Colorretais/sangue , Neoplasias Colorretais/metabolismo , Metilação de DNA , Humanos , MicroRNAs/sangue , MicroRNAs/genética , Obesidade/sangue , Obesidade/metabolismo , PPAR gama/sangue , PPAR gama/metabolismo , Regiões Promotoras Genéticas
6.
Genet Couns ; 27(1): 25-33, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27192889

RESUMO

Autosomal recessive primary microcephaly is a heterogeneous genetic disorder caused by genes that affect neurogenesis. This form of microcephaly has not been associated with other congenital anomalies. ASPM mutations have been identified as the major cause implicated in autosomal recessive primary microcephaly. X-linked recessive ichthyosis, is an inborn error of steroid sulfatase metabolism characterized by dark and adhesive scaly skin. Here, we examined an Egyptian boy presenting with microcephaly and simplified gyral pattern. Additionally, he had ichthyosis that goes with the X-linked type. Mutation analyses of the ASPM gene for autosomal recessive primary microcephaly and STS gene of X-linked recessive ichthyosis were conducted revealing a co-occurrence of a novel homozygous splice site mutation of ASPM gene (c.2936+1G>A) and a partial deletion of STS spanning from exon 7-10. We propose that the phenotype of our patient results from the combined effects of mutations in both ASPM and STS that account for the neurological signs and skin manifestations, respectively. The association of isolated X-linked recessive ichthyosis and autosomal recessive primary microcephaly has never been reported in the literature. Careful clinical and genetic assessment of patients with atypical clinical phenotypes is crucial for detecting such rare double mutations and thus proper genetic counseling.


Assuntos
Ictiose Ligada ao Cromossomo X/genética , Microcefalia/genética , Proteínas do Tecido Nervoso/genética , Esteril-Sulfatase/genética , Pré-Escolar , Consanguinidade , Análise Mutacional de DNA , Deficiências do Desenvolvimento/genética , Egito , Homozigoto , Humanos , Masculino , Mutação
7.
Genome Announc ; 4(3)2016 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-27198011

RESUMO

Mycobacterium tuberculosis is known to cause pulmonary and extrapulmonary tuberculosis. This organism showed special phylogeographical specificity. Here, we report the complete genome sequence of M. tuberculosis clinical isolate spoligotype SIT745/EAI1-MYS, which was isolated from a Malaysian tuberculosis patient.

8.
Sci Rep ; 5: 14537, 2015 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-26455713

RESUMO

A stable dual-wavelength thulium-doped fiber laser operating at 1.9 µm using a short length of photonic crystal fiber (PCF) has been proposed and demonstrated. The photonics crystal fiber was 10 cm in length and effectively acted as a Mach-Zehnder interferometry element with a free spectral range of 0.2 nm. This dual-wavelength thulium-doped fiber laser operated steadily at room temperature with a 45 dB optical signal-to-noise-ratio.

9.
Appl Opt ; 53(30): 7025-9, 2014 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-25402790

RESUMO

In this work, we demonstrated a compact Q-switched erbium-doped fiber laser capable of generating high-energy pulses using a newly developed multiwall carbon nanotube (CNT) polyvinyl alcohol (PVA) thin film based saturable absorber. Q-switched pulse operation is obtained by sandwiching the thin film between two fiber ferrules forming a saturable absorber. A saturable absorber with 1.25 wt. % of PVA concentration shows a consistency in generating pulsed laser with a good range of tunable repetition rate, shortest pulse width, and produces a high pulse energy and peak power. The pulse train generated has a maximum repetition rate of 29.9 kHz with a corresponding pulse width of 3.49 µs as a function of maximum pump power of 32.15 mW. The maximum average output power of the Q-switched fiber laser system is 1.49 mW, which translates to a pulse energy of 49.8 nJ. The proposed method of multiwall CNT/PVA thin film fabrication is low in cost and involves uncomplicated processes.

10.
Appl Opt ; 53(29): 6944-9, 2014 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-25322403

RESUMO

The individual extraction of a Brillouin Stokes line from a 20 GHz comb generated from the compact configuration of a multiwavelength Brillouin fiber ring laser configuration has been achieved using an ultranarrow bandwidth (UNB) optical filter. The narrowest bandwidth transmission of a UNB optical filter that is 50 pm is used in order to get particular Stokes. The Stokes filtered is in the wavelength range of 1549.768-1551.016 nm. High SNR within the range of 54.97-11.73 dB with almost nil peak power loss being obtained was monitored by a 0.16 pm optical spectrum analyzer, giving convincing results. Relatively, the proposed configuration could provide wide tunability and narrow selection of the Brillouin Stokes.

11.
J Mater Sci Mater Med ; 25(8): 1925-39, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24831081

RESUMO

The present study investigates the development of methyl cellulose (MC)-sodium alginate (SA)-montmorillonite (MMT) clay based bionanocomposite films with interesting wound healing properties. The differential scanning calorimetry analysis of the composite films revealed presence of single glass transition temperature (Tg) confirming the miscible nature of the ternary blended films. The increase in MMT ratio in the composite films reduced the mobility of biopolymer chains (MC/SA) which increased the Tg of the film. Thermogravimetric analysis showed that dispersion of clay (MMT) at nano level significantly delayed the weight loss that correlated with higher thermal stability of the composite films. It was observed that the developed films were able to exhibit antimicrobial activity against four typical pathogenic bacteria found in the presence of wound. The developed films were able to significantly inhibit (10 mg/ml) the growth of Enterococcus faecium and Pseudomonas aeruginosa. In vitro scratch assay indicated potential wound closure activities of MC-2-4 bionanocomposite films at their respective highest subtoxic doses. In conclusion, these ternary bionanocomposite films were found to be promising systems for wound healing applications.


Assuntos
Silicatos de Alumínio , Antibacterianos/farmacologia , Nanocompostos , Cicatrização , Varredura Diferencial de Calorimetria , Células Cultivadas , Argila , Enterococcus faecium/efeitos dos fármacos , Humanos , Técnicas In Vitro , Testes de Sensibilidade Microbiana , Microscopia Eletrônica , Pseudomonas aeruginosa/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria
12.
Gen Comp Endocrinol ; 170(1): 125-30, 2011 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-20888822

RESUMO

Annual gonad hormonal profile of wild, matured mahseer (29 males and 23 female) averaging in weight between 0.95±0.26 and 1.19±0.23 kg for males and females, respectively, were investigated from November 2007 to November 2008 using enzyme-linked immunosorbent assay (ELISA) technique. Blood was collected from caudal vein, monthly and plasma separation by centrifugation was done to measure reproductive hormones: 17ß-estradiol (E(2)), testosterone (T), and 11-keto-testosterone (11KT). Gonads were sampled for histology processing to observe their maturity. Highest T level in females and males was recorded at 0.22±0.016 and 0.88±0.014 ng/ml, respectively. The 11KT showed several peaks and the highest value was noted at 0.7±0.018 ng/ml in November 2008. The female E(2) initially was at 1.48±0.16 ng/ml and significantly increased (P<0.05) to 1.53±0.39 ng/ml in November 2008. Ovaries were laden with oocytes in several stages in all the samples while testes gonad showed a high level of spermatids throughout the year. Changes in plasma level of the gonadal hormones were correlated with the ovarian and testes maturities. In conclusion, the study suggests that mahseer can be categorized as asynchronized and multiple spawner. The information gathered is important for appropriate breeding and conservation programs of the Malaysian mahseer.


Assuntos
Estradiol/metabolismo , Gônadas/crescimento & desenvolvimento , Gônadas/metabolismo , Testosterona/análogos & derivados , Testosterona/metabolismo , Animais , Cyprinidae/crescimento & desenvolvimento , Cyprinidae/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Masculino , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Testículo/crescimento & desenvolvimento , Testículo/metabolismo
13.
East Mediterr Health J ; 17(11): 855-61, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22276494

RESUMO

There are no data on the knowledge, attitude and practices of Qatari women about this cancer. Therefore this cross-sectional interview-based study was conducted in 2008 among 500 women at 5 randomly selected primary health care centres in Qatar to determine their knowledge, attitude and practices regarding cervical cancer and screening. Just over 85% had heard of cervical cancer and 76% had heard about the Pap smear. Knowledge of cervical cancer was significantly greater among women aged 30-49 years, and those employed, married for > 15 years, with a university degree, or who had had 4 births or 3 miscarriages. Almost 40% had had a Pap smear test at least once and 85.5% of the rest would have a test if they were told that the procedure was painless and simple. Over half wanted the test to be done in the well-woman clinic at the primary health care centre. Knowledge and practice as inadequate among those under 30 years old, those recently married and those with a lower education level.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Programas de Rastreamento , Atenção Primária à Saúde , Neoplasias do Colo do Útero/diagnóstico , Adulto , Estudos Transversais , Feminino , Humanos , Entrevistas como Assunto , Pessoa de Meia-Idade , Catar , Adulto Jovem
14.
(East. Mediterr. health j).
em Inglês | WHO IRIS | ID: who-118198

RESUMO

There are no data on the knowledge, attitude and practices of Qatari women about this cancer. Therefore this cross-sectional interview-based study was conducted in 2008 among 500 women at 5 randomly selected primary health care centres in Qatar to determine their knowledge, attitude and practices regarding cervical cancer and screening. Just over 85% had heard of cervical cancer and 76% had heard about the Pap smear. Knowledge of cervical cancer was significantly greater among women aged 30-49 years, and those employed, married for > 15 years, with a university degree, or who had had 4 births or 3 miscarriages. Almost 40% had had a Pap smear test at least once and 85.5% of the rest would have a test if they were told that the procedure was painless and simple. Over half wanted the test to be done in the well-woman clinic at the primary health care centre. Knowledge and practice was inadequate among those under 30 years old, those recently married and those with a lower education level


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Programas de Rastreamento , Atenção Primária à Saúde , Estudos Transversais , Inquéritos e Questionários , Neoplasias do Colo do Útero
16.
(East. Mediterr. health j).
em Inglês | WHO IRIS | ID: who-117910

RESUMO

A cross-sectional study of knowledge, attitudes and practice of general practitioners [GPs] towards complementary and alternative medicine [CAM] was conducted in Doha, Qatar. Out of 119 respondents, 39.1% reported poor knowledge about CAM. Self-reported knowledge was highest for counselling and psychotherapy [69.0%], diet and supplements [68.1%], acupuncture [45.2%], herbal medicine [47.3%] and massage [42.5%]. While 83.8% described their attitude to CAM as welcoming and 97.5% were interested to learn more about it, fewer [30.1%] had practised it before, referred patients [24.8%] or asked patients' about their use of CAM [34.8%]. Their own lack of knowledge and training in CAM was seen as a barrier to its use by 60.0% of the GPs


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Estudos Transversais , Médicos de Família , Medicina Herbária , Inquéritos e Questionários , Terapias Complementares
17.
Arch Pharm Res ; 31(5): 562-8, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18481009

RESUMO

Three novel series of 2-(substituted phenyl)-4-(substituted arylidene)-imidazolone-5-(4H)-ones were derived from the corresponding oxazolones by condensation with different arylamines. Eleven of the synthesized compounds were selected and evaluated for their effect on carrageenan-induced rat paw edema. Compound 4b had the same efficacy as the reference standard (indomethacin), and compounds 3b, 3c, 4a, 4d and 9a showed good to excellent activities, with other compounds only weakly active. The potent compounds were evaluated for their inhibitory activities against COX-2-catalyzed PGE(2) production, with 4a, 4b and 3c showing strong inhibitory activity.


Assuntos
Inibidores de Ciclo-Oxigenase 2/síntese química , Imidazóis/síntese química , Animais , Carragenina , Inibidores de Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase 2/farmacologia , Dinoprostona/sangue , Edema/induzido quimicamente , Edema/tratamento farmacológico , Feminino , Humanos , Imidazóis/química , Imidazóis/farmacologia , Técnicas In Vitro , Masculino , Ratos
18.
Pharmacol Res ; 39(2): 157-66, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10072708

RESUMO

Experimental hypercholesterolemia and its modulation by some natural dietary supplements (pectin, garlic and ginseng) and by the drug gemfibrozil were studied. Experimental hypercholesterolemia was induced by feeding rabbits a 2% cholesterol-enriched diet for 28 days. Hypercholesterolemic rabbits were classified into five groups. One group did not receive treatments and served as a control hypercholesterolemic group. The other four groups were fed the cholesterol-enriched diet in conjunction with either 10% pectin, 2% garlic, 2% ginseng or 135 mg g-1 b.w gemfibrozil in a daily oral dose. A normal group of rabbits fed a plain chow diet was also included in the study. The hypolipidemic effect of the above treatments was examined by estimating serum triglycerides (TG), total-, LDL- and HDL-cholesterol. Post-heparin total and hepatic lipase activities were estimated in post-heparin plasma obtained 10 min after an intravenous injection of heparin (200 IU kg-1 b.w). In order to evaluate the antioxidant status of the rabbits, plasma malondialdehyde (MDA) level and erythrocyte superoxide dismutase (SOD) activity were measured. After killing, aorta from all rabbits were subjected to histopathological examination. Results of the study demonstrated that feeding the cholesterol-enriched diet caused a significant increase in total-, LDL-, and HDL-cholesterol, plasma MDA and post-heparin total and hepatic lipase activities. On the other hand, serum TG and erythrocyte SOD were not changed. Histopathological examination revealed marked alteration in the aortic wall with the appearance of large multiple atheromatous plaques. Both garlic and pectin were successful in a significant reduction of the hypercholesterolemia in a way comparable to gemfibrozil. Garlic was the only treatment that has antilipid peroxidative property. Erythrocyte SOD activity was not affected by hypercholesterolemia or by any of the treatments. Also, none of the treatments were able to modify the significant elevation of post-heparin lipolytic activities associated with the hypercholesterolemia or to significantly affect the serum triglycerides level. Finally, among the hypercholesterolemic groups that received treatments, the least changes in the aortic wall were shown in the animals of the gemfibrozil group. Slight degeneration was observed in the aorta of animals treated with pectin or garlic. Ginseng administration failed to exert any significant protection from the remarkable hypercholesterolemia or atherosclerosis associated with the cholesterol- enriched diet.


Assuntos
Alho/química , Hipercolesterolemia/tratamento farmacológico , Hipolipemiantes/farmacologia , Panax/química , Pectinas/farmacologia , Plantas Medicinais , Animais , Aorta/patologia , Colesterol/sangue , Colesterol na Dieta/administração & dosagem , Genfibrozila/farmacologia , Hipercolesterolemia/sangue , Hipercolesterolemia/patologia , Masculino , Fotomicrografia , Coelhos , Superóxido Dismutase/sangue , Triglicerídeos/sangue
19.
Arch Androl ; 39(1): 19-23, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9202829

RESUMO

Sperm head differentiation in Mabuya quinquetaeniata agrees in the main features with that of Agama adramitana, Agama blandfordi, and Acanthodactylus boskianus. The development of subacrosomal lateral canals, the disappearance of translucent medulla, and the existence of unilateral dense acrosome are new findings of the present investigation.


Assuntos
Lagartos , Cabeça do Espermatozoide/fisiologia , Espermatogênese , Animais , Núcleo Celular , Complexo de Golgi , Masculino
20.
Arch Androl ; 28(3): 223-34, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1530371

RESUMO

In addition to the common features of spermiogenesis in Reptilia, new structures are seen in Agama adramitana that have not been described in previous studies. Two acrosomal granules are observed in the acrosomal vesicle. The posterior acrosomal granule differentiates as an anterior electron-dense material in the acrosome, and the anterior one forms a posterior translucent component of the acrosome. Also, the subacrosomal granule spreads in the subacrosomal space as a subacrosomal nuclear cap.


Assuntos
Espermatogênese , Espermatozoides/ultraestrutura , Animais , Lagartos , Masculino , Espermatozoides/citologia
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