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1.
Vet Res Commun ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38958815

RESUMO

Freshwater scarcity poses challenges to aquaculture worldwide, including countries like Egypt. In this study, we investigate the feasibility of integrating underground saline water (USW) with varying salinities into a Biofloc (BFT) system for desert mariculture of Florida red tilapia (FRT) and its impacts on water quality, fish performance and health. Four BFT treatments (C/N ratio = 15) were examined in triplicate using four salinity levels 0 ppt, 12 ppt, 24 ppt and 36 ppt, expressed as S0, S12, S24 and S36, respectively. For 75 days, a total of 12 fiberglass tanks (each 250 L-1 water) were used to store FRT fry (average weight of 1.73 ± 0.01 g/fish). The fish were fed an experimental diet (protein/fat = 30/5) and an additional carbon source of rice bran. The results revealed that group S12 showed better growth indicators, higher survival rate, lower FCR, and lower ammonia levels, while group S0 exhibited lower growth indicators (final weight, weight gain, and specific growth rate) than all groups. The serum kidney, liver, and antioxidant indices performed better in the S12 group. At 12 ppt, the immune-related parameter (IgM) increased by 22.5%, while the stress parameter (cortisol) decreased by 40.8% compared to the S0 group. The liver and intestinal histopathological results revealed that the S12 and S24 groups performed better. Pathogenic bacterial load counts favored the S24 group, which had the lowest number among the groups studied. The recommended salinity for FRT cultivation in USW and BFT is 19.94-20 ppt, determined by polynomial regression of FW and FCR.

2.
Sci Rep ; 14(1): 13868, 2024 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879696

RESUMO

The purpose of this research was to examine the potential effects of bentonite (BN) supplemented diets on growth, feed utilization, blood biochemistry, and histomorphology of Dicentrarchus labrax. Six treatments in triplicate were tested: B0, B0.5, B1.0, B1.5, B3.0, and B4.5, which represented fish groups fed diets supplemented with 0, 0.5, 1, 1.5, 3, and 4.5% BN, respectively. For 84 days, juveniles' seabass (initial weight = 32.73 g) were fed diets containing 46% protein, three times daily at 3% of body weight. With a 5% daily water exchange, underground seawater (32 ppt) was used. Findings revealed significant improvements in water quality (TAN and NH3), growth (FW, WG and SGR) and feed utilization (FCR, PER and PPV) in fish fed BN-supplemented diets, with the best values in favor of the B1.5 group. Additional enhancements in kidney function indicators (urea and uric acid) and liver enzymes were observed in fish of the BN-treated groups along with a decrease in cholesterol level in the B1.5 group. Further improvements in fish innate immunity (hemoglobin, red blood cells, glucose, total protein, globulin, and immunoglobulin IgM), antioxidant activity (total antioxidative capacity and catalase), and decreased cortisol levels in fish of the BN-treated groups. Histological examinations of the anterior and posterior intestines and liver in groups B1.5 and B3 revealed the healthiest organs. This study recommends BN at a concentration of 1.5% as a feed additive in the Dicentrarchus labrax diet.


Assuntos
Amônia , Ração Animal , Antioxidantes , Bass , Bentonita , Suplementos Nutricionais , Animais , Bass/imunologia , Bass/crescimento & desenvolvimento , Bass/metabolismo , Antioxidantes/metabolismo , Bentonita/farmacologia , Bentonita/administração & dosagem , Amônia/metabolismo , Ração Animal/análise , Dieta/veterinária
3.
Opt Express ; 32(9): 16027-16039, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38859240

RESUMO

We present the theory and experimental results of a microwave photonic (MWP) filter based instantaneous frequency measurement system. A quantum dash mode-locked laser is used as an optical frequency comb source. With up to 41 flat comb lines and a real-time feedback loop for comb shaping, a set of MWP filters with linear frequency responses for either linear unit or dB unit are experimentally demonstrated. The maximum measurement frequency can be up to 20 GHz limited by the available test-and-measurement instruments. By using one MWP filter, the root-mean-square error is 51∼66 MHz, which can be improved to 42.2 MHz for linear unit, and 30.7 MHz for dB unit by using two MWP filters together.

4.
PLoS One ; 19(4): e0297844, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38578758

RESUMO

The present study aims to investigate the influence of zeolite usage and stocking densities on various parameters, including ammonia removal from water, accumulation of heavy metals in fish organs, water quality, growth performance, feed efficiency, muscle composition, as well as hematological and biochemical parameters in European seabass (Dicentrarchus labrax) over a 90-day duration. A total of 2400 D. labrax with an initial weight of 9.83 ± 2.02 g and initial length of 9.37 ± 0.32 cm were distributed among 24 tanks. The research involved six distinct treatment groups, with two different zeolite levels (0 and 15 ppt) and three stocking density levels (50, 100, and 150 fish/m3), each replicated four times. The results of the research demonstrate a statistically significant improvement (p < 0.05) in water quality measures with the introduction of zeolite. The successful implementation of this amendment mitigated the adverse effects of fish density on water quality parameters. Higher stocking density negatively impacted European sea bass growth, feed utilization, and hemato-biochemical indicators. Zeolite use effectively alleviated these adverse effects, particularly on performance, feed utilization, hematological, and biochemical parameters. The study's results indicate that the utilization of zeolite has shown to be efficacious in mitigating the accumulation of heavy metals in both water and fish organs, while concurrently augmenting fish attributes. However, the increase in density led to a significant decrease in the accumulation of heavy metals in both water and fish organs. The present study highlights the capacity of natural zeolites to mitigate the negative consequences associated with water quality concerns. The efficiency of these zeolites in limiting the accessibility of heavy metals in polluted water is shown, hence minimizing their accumulation in fish organs. In addition, the improvement of fish performance has the capacity to have a beneficial influence on both the well-being and efficiency of fish in aquaculture. Additional research is essential to fully understand the complex molecular pathways involved in utilizing natural zeolite under different fish densities.


Assuntos
Bass , Metais Pesados , Zeolitas , Animais , Bass/fisiologia , Amônia/metabolismo , Metais Pesados/metabolismo , Músculos/metabolismo
5.
Sci Rep ; 13(1): 21801, 2023 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-38065998

RESUMO

This study aimed to assess the impact of spirulina and/or canthaxanthin-enriched Artemia on the goldfish (Carassius auratus) growth, pigmentation, blood analysis, immunity, intestine and liver histomorphology, and expression of somatolactin (SL) and growth hormone (GH) genes. Artemia was enriched with spirulina and/or canthaxanthin for 24 h. Goldfish (N = 225, 1.10 ± 0.02 g) were tested in five experimental treatments, three replicates each: (T1) fish fed a commercial diet; (T2) fish fed a commercial diet and un-enriched Artemia (UEA); (T3) fish fed a commercial diet and spirulina-enriched Artemia (SEA); (T4) fish fed a commercial diet and canthaxanthin-enriched Artemia (CEA); and (T5) fish fed a commercial diet and spirulina and canthaxanthin-enriched Artemia (SCA) for 90 days. The results showed that the use of spirulina and/or canthaxanthin increased performance, ß-carotene content and polyunsaturated fatty acids of Artemia. For goldfish, T5 showed the highest growth performance, ß-carotene concentration and the lowest chromatic deformity. T5 also showed improved hematology profile, serum biochemical, and immunological parameters. Histomorphology of the intestine revealed an increase in villi length and goblet cells number in the anterior and middle intestine, with normal liver structure in T5. SL and GH gene expression in the liver and brain differed significantly among treatments with a significant increase in enriched Artemia treatments compared to T1 and T2. In conclusion, the use of spirulina and/or canthaxanthin improved performance of Artemia. Feeding goldfish spirulina and/or canthaxanthin-enriched Artemia improved performance, ß-carotene content, pigmentation, health status and immune-physiological response.


Assuntos
Artemia , Carpa Dourada , Animais , Artemia/genética , beta Caroteno , Cantaxantina , Dieta , Pigmentação , Perfilação da Expressão Gênica
6.
Micromachines (Basel) ; 14(12)2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38138398

RESUMO

We present here a performance comparison of quantum-dash (Qdash) semiconductor amplifiers (SOAs) with three, five, eight, and twelve InAs dash layers grown on InP substrates. Other than the number of Qdash layers, the structures were identical. The eight-layer Qdash SOA gave the highest amplified spontaneous emission power (4.3 dBm) and chip gain (26.4 dB) at 1550 nm, with a 300 mA CW bias current and at 25 °C temperature, while SOAs with fewer Qdash layers (for example, three-layer Qdash SOA), had a wider ASE bandwidth (90 nm) and larger 3 dB gain saturated output power (18.2 dBm) in a shorter wavelength range. The noise figure (NF) of the SOAs increased nearly linearly with the number of Qdash layers. The longest gain peak wavelength of 1570 nm was observed for the 12-layer Qdash SOA. The most balanced performance was obtained with a five-layer Qdash SOA, with a 25.4 dB small-signal chip gain, 15.2 dBm 3 dB output saturated power, and 5.7 dB NF at 1532 nm, 300 mA and 25 °C. These results are better than those of quantum well SOAs reported in a recent review paper. The high performance of InAs/InP Qdash SOAs with different Qdash layers shown in this paper could be important for many applications with distinct requirements under uncooled scenarios.

7.
Acta Parasitol ; 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38015315

RESUMO

PURPOSE: Ticks infestation has a negative impact against human and animal health through blood sucking, transmission of blood-borne diseases and also caused economic losses. METHODS: In the present study the adulticidal, ovicidal and larvicidal activity of D-limonene nanoemulsion (DLN) were evaluated against two tick species; Rhipicephalus annulatus and Rhipicephalus sanguineus. Nanoemulsion form of D-limonene was prepared, and its characteristics were evaluated using a UV spectrophotometer and zeta droplet size measurement. Acetylcholinesterase activity was determined. RESULTS: The results revealed significant adulticidal effect with low LC50 and LC90 for D-limonene pure form (DL) against both adult tick spp. (R. annulatus and R. sanguineus) ((0.958 and 1.559%) and (2.26 and 3.51%), respectively). DLN LC50 and LC90 values were ((1.277 and 2.396) and (3.97 and 7.28), respectively) against R. annulatus and R. sanguineus, respectively. DL and DLN showed significant ovicidal effect against R. sanguineus at high concentrations (10 and 5%). In larval packet test, LC50 and LC90 values of DL were ((1.53 and 2.22%) and (6.81 and 12.07%), respectively) against R. annulatus and R. sanguineus, respectively, while LC50 and LC90 values of DLN were ((6.48 and 11.26%) and (7.82 and 13.59%), respectively) against R. annulatus and R. sanguineus, respectively. Significant acetylcholinesterase inhibition percentage was detected for both ticks spp. which treated by DL and DLN. CONCLUSION: Pure DL is more effective than DLN form against R. annulatus and R. sanguineus.

8.
Aquac Nutr ; 2023: 8860652, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023984

RESUMO

A 120-day growth trial was completed to assess rearing water quality and fish performance in terms of growth, feed efficacy, digestive enzymes, immunity, and antioxidant activity of seabass fed an experimental diet (ED) supplemented with commercial wood charcoal (WC) and activated wood charcoal (AC). Three levels (0, 10, and 20 g) of WC and AC were administered, representing five treatments: control (CD) fish-fed ED without additives, (WC-1) fish-fed ED containing 10 g kg-1 WC, (WC-2) fish-fed ED containing 20 g kg-1 WC, (AC-1) fish-fed ED containing 10 g kg-1 AC, and (AC-2) fish-fed ED containing 20 g kg-1 AC. Three hundred fish (60.12 ± 0.20 g/fish) were stocked in 15 cement tanks (4.0 m × 2.0 m × 1.2 m, water volume 5 m3 each) at 20 fish/tank and a daily feed ration of 3% of body weight. Results revealed significant improvements with increased growth variables (final weight, weight gain, and specific growth rate), decreased FCR, and decreased ammonia levels and heavy metals (Cu, Cd, Fe, Mn, and Zn) content in rearing water, muscle, and liver with fish fed WC and AC supplemented diets. Furthermore, considerable improvements in digestive enzymes, immunity, and antioxidant activity, with enhanced kidneys, liver, intestines, gills, and spleen. Fish fed the WC-1 diet had a higher final weight (171.90 g), better FCR (1.25), and improved internal organs than the other groups.

9.
Artigo em Inglês | MEDLINE | ID: mdl-35162527

RESUMO

BACKGROUND: The epidemiology of schistosomiasis transmission varies depending on the circumstances of the surrounding water bodies and human behaviors. We aimed to explore cercarial emergence patterns from snails that are naturally affected by human schistosomiasis and non-human trematodes. In addition, this study aimed to explore how schistosomiasis infection affects snail survival, reproduction, and growth. METHODS: We measured the survival rate, fecundity, and size of Biomphalaria pfeifferi snails and the cercarial rhythmicity of S. haematobium and S. mansoni. The number of egg masses, eggs per egg mass, and snail deaths were counted for 7 weeks. The survival rate and cumulative hazard were assessed for infected and non-infected snails. RESULTS: S. haematobium and S. mansoni cercariae peaked at 9:00-11:00 a.m. Infection significantly reduced the survival rate of B. pfeifferi, which was 35% and 51% for infected and non-infected snails, respectively (p = 0.02), at 7 weeks after infection. The hazard ratio of death for infected snails compared to non-infected snails was 1.65 (95% confidence interval: 1.35-1.99; p = 0.01). CONCLUSIONS: An understanding of the dynamics of schistosomiasis transmission will be helpful for formulating schistosomiasis control and elimination strategies. Cercarial rhythmicity can be reflected in health education, and the reproduction and survival rate of infected snails can be used as parameters for developing disease modeling.


Assuntos
Biomphalaria , Parasitos , Animais , Biomphalaria/parasitologia , Rios , Schistosoma haematobium , Schistosoma mansoni , Sudão
10.
Opt Express ; 29(11): 16164-16174, 2021 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-34154184

RESUMO

We have developed and experimentally demonstrated a highly coherent and low noise InP-based InAs quantum dash (QDash) buried heterostructure (BH) C-band passively mode-locked laser (MLL) with a pulse repetition rate of 25 GHz for fiber-wireless integrated fronthaul 5G new radio (NR) systems. The device features a broadband spectrum providing over 46 equally spaced highly coherent and low noise optical channels with an optical phase noise and integrated relative intensity noise (RIN) over a frequency range of 10 MHz to 20 GHz for each individual channel typically less than 466.5 kHz and -130 dB/Hz, respectively, and an average total output power of ∼50 mW per facet. Moreover, the device exhibits low RF phase noise with measured RF beat-note linewidth down to 3 kHz and estimated timing jitter between any two adjacent channels of 5.5 fs. By using this QDash BH MLL device, we have successfully demonstrated broadband optical heterodyne based radio-over-fiber (RoF) fronthaul wireless links at 5G NR in the underutilized spectrum of around 25 GHz with a total bit rate of 16-Gb/s. The device performance is experimentally evaluated in an end-to-end fiber-wireless system in real-time in terms of error vector magnitude (EVM) and bit error rate (BER) by generating, transmitting and detecting 4-Gbaud 16-QAM RF signals over 0.5-m to 2-m free-space indoor wireless channel through a total length of 25.22 km standard single mode fiber (SSMF) with EVM and BER under 8.4% and 2.9 × 10-5, respectively. The intrinsic characteristics of the device in conjunction with its system transmission performance indicate that QDash BH MLLs can be readily used in fiber-wireless integrated systems of 5G and beyond wireless communication networks.

11.
Mar Drugs ; 19(3)2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33806929

RESUMO

This study was aimed to evaluate the efficiency of Sargassumpolycystum and nucleotides- supplemented diets to improve immune response and cold-tolerance of juvenile Litopenaeus vannamei. Four treatments were evaluated: T1, the control, shrimp received only a basal diet; T2, a basal diet with 500 ppm nucleotides; T3, a basal diet with 500 ppm S.polycystum powdered; T4, a basal diet with 500 ppm nucleotides and 500 ppm S.polycystum powdered. Shrimp were fed experimental diets for 56 days. Results revealed shrimp fed T4 diet exhibited the best significant improvement in water quality, survival, growth, and feed utilization indices followed by T2, and T3, while T1 showed the worst values. Additionally, nonspecific immune responses (phagocytosis (%), lysozyme, phenoloxidase, super oxide dismutase (SOD) activity, total nitric oxide) were improved with 1.7-3.2-fold in T4 higher than T1. Histomorphology of hepatopancreas in T4 showed the most increased activation of the hepatic glandular duct system compared with the other treatments. Moreover, nucleotides/seaweed-supplemented diets upregulated relative expression of cMnSOD, Penaeidin4, and heat shock protein70 (HSP70) genes, while translationally controlled tumor protein (TCTP) was downregulated. In conclusion, the synergistic effects of both S. polycystum and nucleotides have many advantages as a growth promoter, immunostimulant, antimicrobial, and cold-tolerant stimulant to L. vannamei.


Assuntos
Temperatura Baixa , Suplementos Nutricionais , Nucleotídeos/administração & dosagem , Penaeidae/fisiologia , Sargassum , Estações do Ano , Alga Marinha , Frutos do Mar , Aclimatação , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Aquicultura , Regulação da Expressão Gênica , Estado Nutricional , Valor Nutritivo , Penaeidae/genética , Penaeidae/crescimento & desenvolvimento , Fatores de Tempo
12.
Carbohydr Res ; 491: 107980, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32199172

RESUMO

The formation of host-guest complex between benzyl isothiocyanate (BITC) and ß-cyclodextrin (ß-CD) was studied using dispersion-corrected density functional theory calculations. The complexation process was monitored using molecular docking simulations, natural bond orbital (NBO) technique, nuclear magnetic resonance (1H NMR) chemical shift calculations and non-covalent interactions (NCI) analysis. All these approaches are consistent with experimental findings. The calculated complexation energy was negative indicating the formation of inclusion complex. The most stable complexation of BITC involves the inclusion of its aromatic moiety in ß-CD cavity (model A) in accord with experimental NMR chemical shift data. The non-covalent interactions (NCI) based on the reduced density gradient (RDG) analysis reveal that mainly weak Van der Waals intermolecular interactions between BITC and ß-CD provide and ensure stability for the complexation process.


Assuntos
Teoria da Densidade Funcional , Isotiocianatos/química , beta-Ciclodextrinas/química , Modelos Moleculares , Estrutura Molecular
13.
Opt Express ; 27(24): 35368-35375, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31878707

RESUMO

We have developed and experimentally demonstrated a novel monolithic InAs/InP quantum-dash dual-wavelength distributed feedback (QD DW-DFB) C-band laser as a compact optical beat source to generate millimeter-wave (MMW) signals. The device uses a common gain medium in a single cavity structure for simultaneous correlated and stable dual-mode lasing in the 1550-nm wavelength range. A record narrow optical linewidth down to 15.83 kHz and average relative intensity noise (RIN) as low as -158.3 dB/Hz from 10 MHz to 20 GHz are experimentally demonstrated for the two optical modes generated by the laser. As a result, the beat note between these two lasing modes generates spectrally pure MMW signals between 46 GHz and 48 GHz. Such an efficient, coherent, and compact optical source is extremely attractive for applications in MMW systems, such as Radar and fiber-wireless integrated fronthaul for 5G and beyond.

14.
Sultan Qaboos Univ Med J ; 17(2): e135-e146, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28690884

RESUMO

Pseudoaneurysms (PSAs) of the hepatic and/or cystic artery are a rare complication following a laparoscopic cholecystectomy (LC). Generally, PSA cases present with haemobilia several weeks following the procedure. Transarterial embolisation (TAE) is considered the optimal management approach. We report a 70-year-old woman who presented to the Sultan Qaboos University Hospital, Muscat, Oman, in 2016 with massive hemoperitoneum two weeks after undergoing a LC procedure in another hospital. She was successfully managed using coil TAE. An extensive literature review revealed 101 cases of hepatic or cystic artery PSAs following a LC procedure. Haemobilia was the main presentation (85.1%) and the mean time of postoperative presentation was 36 days. The hepatic artery was involved in most cases (88.1%), followed by the cystic artery (7.9%) and a combination of both (4.0%). Most cases were managed with TAE (72.3%), with a 94.5% success rate. The overall mortality rate was 2.0%.


Assuntos
Falso Aneurisma/etiologia , Colecistectomia Laparoscópica/efeitos adversos , Artéria Hepática , Complicações Pós-Operatórias/etiologia , Idoso , Falso Aneurisma/diagnóstico por imagem , Falso Aneurisma/terapia , Ductos Biliares/irrigação sanguínea , Feminino , Doenças da Vesícula Biliar/diagnóstico por imagem , Doenças da Vesícula Biliar/etiologia , Hemobilia/etiologia , Hemoperitônio/diagnóstico por imagem , Hemoperitônio/etiologia , Artéria Hepática/diagnóstico por imagem , Humanos , Omã , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/terapia
15.
Exp Clin Transplant ; 15(6): 627-630, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28661315

RESUMO

OBJECTIVES: New-onset diabetes after transplant is a well-recognized complication of solid-organ transplant. The true incidence of this complication in Sudan is not known. The aim of this study was to define the prevalence of new-onset diabetes after transplant in a Sudanese renal transplant population and to identify the contributing risk factors. MATERIALS AND METHODS: Fifty-nine patients who underwent living-donor related kidney transplant and who were followed for 2 years were included in this pilot study. Only patients who were not diabetic before transplant were included. Patients who developed new-onset diabetes after transplant were compared with those who did not develop type 2 diabetes mellitus. The variables analyzed were age, sex, body mass index, family history of type 2 diabetes mellitus, and interval between time of transplant and onset of diabetes. RESULTS: Five patients (5/58) developed diabetes after transplant (8.62%). There was no association between new-onset diabetes after transplant and age, sex, and body mass index. However, there was a strong association between family history of diabetes and new-onset diabetes after transplant. The mean duration for developing new-onset diabetes after transplant was 10 months posttransplant. Patients in the new-onset diabetes after transplant group had no graft loss or deterioration in graft function compared with those who did not develop diabetes. CONCLUSIONS: The prevalence of new-onset diabetes after transplant in our studied Sudanese population was found to be < 10%. There was no association between new-onset diabetes after transplant and age, sex, and body mass index. However, there was a significant association with family history of diabetes mellitus.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Transplante de Rim/efeitos adversos , Adolescente , Adulto , Estudos Transversais , Diabetes Mellitus Tipo 2/diagnóstico , Feminino , Humanos , Incidência , Transplante de Rim/métodos , Doadores Vivos , Masculino , Pessoa de Meia-Idade , Linhagem , Projetos Piloto , Prevalência , Medição de Risco , Fatores de Risco , Sudão/epidemiologia , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
16.
Lab Chip ; 15(9): 2073-89, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-25813089

RESUMO

Polydimethylsiloxane stamp materials used during soft lithography undermine the non-fouling behaviour of bio-inert PEG-based hydrogels, resulting in increased protein adsorption and cell adhesion and migration on the gel. This previously unreported phenomenon undermines the function of lab-on-a-chip devices that require the device to be bio-inert, and slows the implementation of promising micromolding and imprinting methods for 3D culture and commercial cell culture systems. We illustrate that the degree of cell adhesion and protein adsorption to the gels correlates with the amount of residual stamp material remaining at the hydrogel interface after fabrication. After identifying this previously unreported phenomenon, we screened multiple polymer cleaning/fabrication techniques in order to maintain/restore the non-fouling properties of the gels including PDMS curing and extraction, use of other common soft lithography stamp materials, post-fabrication cleaning of the hydrogels, and changing the composition of the hydrogel. The optimal solution was determined to be incorporation of reactive sites into the hydrogel during micromolding followed by grafting of PEG macromers to these sites post-fabrication. This treatment resulted in micromolded hydrogels with robust cell resistant properties. Broadly, this work identifies and solves a previously unreported problem in hydrogel micromolding, and specifically reports the development of a cell culture platform that when combined with video microscopy enables high-resolution in situ study of single cell behaviour during in vitro culture.


Assuntos
Hidrogéis/química , Hidrogéis/farmacologia , Microtecnologia/métodos , Polietilenoglicóis/química , Adsorção , Incrustação Biológica/prevenção & controle , Adesão Celular/efeitos dos fármacos , Dimetilpolisiloxanos/química , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Proteínas/química
17.
Sultan Qaboos Univ Med J ; 15(1): e133-5, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25685374

RESUMO

Cerebellar mutism is a rare occurrence following paediatric trauma. Although it is quite common after posterior fossa surgery in children, this phenomenon has rarely been reported following other insults, such as trauma, and its pathophysiology remains poorly understood. We report a seven-year-old child who presented to the casualty department of Sultan Qaboos University Hospital in Muscat, Oman, in May 2013 with a traumatic right cerebellar contusion. The child presented with clinical features of cerebellar mutism but underwent a rapid and spontaneous recovery. The possible mechanism of this occurrence is discussed.

18.
Cell Biochem Biophys ; 71(2): 617-25, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25239021

RESUMO

Hepatitis C virus (HCV) is a major cause of chronic liver disease, with about 170 million people infected worldwide. The standard regimen for treatment of HCV consists of a combination of pegylated interferon with ribavirin. Failure of interferon-α treatment in patients with chronic HCV infection remains a challenging obstacle. Both viral and host environmental factors have been implicated in reducing responsiveness to IFN-α therapy. Host genetic diversity is also believed to contribute to the different clinical outcomes in HCV infection. The objective of the study was to investigate the association of both IL-10 (-819 and -592) and MxA (-88 and -123) single-nucleotide polymorphisms (SNPs) of the promoter regions, with response to interferon (IFN) therapy in Egyptian patients infected with HCV genotype 4. Polymorphisms of both genes in 85 HCV patients and 100 controls were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. The frequency of SNP was compared between sustained responders (n = 52) and non-responders (n = 33), as determined by biochemical and virological response to IFN and ribavirin combined therapy. The frequency of the -819T/T and the -592A/A genotypes of IL-10 was significantly higher among responders compared to non-responders (51.92 vs 39.4 %, P = 0.03; 51.92 vs 42.42 %;P = 0.046 respectively). The G/G genotype at position -88 of the MxA gene was significantly lower in responders than in non-responders (25 vs 75.76 %, P = 0.046), whereas heterozygotes (G/T) were more likely responders (65.38 vs 18.18 %, P = 0). The -123C/A genotype was significantly associated with responders (48.08 vs 30.30 %, P = 0.014). Findings suggest that homozygosity for both -819T/T and -592A/A polymorphisms of IL-10 gene and that heterozygosity for both -88G/T and -123C/A polymorphisms of the MxA gene are important host factors that influence the response to IFN therapy in patients with chronic HCV infection.


Assuntos
Hepatite C Crônica/genética , Interferons/uso terapêutico , Interleucina-10/genética , Proteínas de Resistência a Myxovirus/genética , Polimorfismo de Nucleotídeo Único , Adulto , Estudos de Casos e Controles , Egito , Feminino , Genótipo , Hepatite C Crônica/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Regiões Promotoras Genéticas
19.
ISRN Vet Sci ; 2014: 595724, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25002977

RESUMO

The objectives of this cross-sectional study were to determine the seroprevalence of blue tongue virus (BTV) and assess potential risk factors associated with BTV infection in dairy cattle with reproductive problems in Sudan. Serum samples were collected from a total of 784 animals from 37 herds and tested for antibodies against BTV using cELISA. A total of 663 out of 784 (84.57%) sera tested proved positive for BTV antibodies in all farms tested in Khartoum and Gazira States. The prevalence of antibodies was high in both areas being 94.32% in Gazira State and 76.62% in Khartoum State. BTV antibodies prevalence were significantly higher (P < 0.000) in older animals than in younger ones. These rates were also significantly higher in the rainy season (P < 0.000) and in Gazira State compared to Khartoum State. Sex also showed significant (P < 0.000) differences in the seroprevalence, whereby females (74.7%) had higher level than males (9.8%). However, no significant (P > 0.09) variations for BTV seroprevalence were observed between breeds. The BTV antibodies prevalence in infertility cases (86.6%) was not significantly different from that found in abortion (74.3%) or neonatal death (66.7%) cases. The high seroprevalence of BTV recorded herein calls for control strategy to be implemented.

20.
Biomaterials ; 35(13): 4046-57, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24560460

RESUMO

Large-scale expansion of highly functional adult human mesenchymal stem cells (aMSCs) remains technologically challenging as aMSCs lose self renewal capacity and multipotency during traditional long-term culture and their quality/quantity declines with donor age and disease. Identification of culture conditions enabling prolonged expansion and rejuvenation would have dramatic impact in regenerative medicine. aMSC-derived decellularized extracellular matrix (ECM) has been shown to provide such microenvironment which promotes MSC self renewal and "stemness". Since previous studies have demonstrated superior proliferation and osteogenic potential of human fetal MSCs (fMSCs), we hypothesize that their ECM may promote expansion of clinically relevant aMSCs. We demonstrated that aMSCs were more proliferative (∼ 1.6 ×) on fMSC-derived ECM than aMSC-derived ECMs and traditional tissue culture wares (TCPS). These aMSCs were smaller and more uniform in size (median ± interquartile range: 15.5 ± 4.1 µm versus 17.2 ± 5.0 µm and 15.5 ± 4.1 µm for aMSC ECM and TCPS respectively), exhibited the necessary biomarker signatures, and stained positive for osteogenic, adipogenic and chondrogenic expressions; indications that they maintained multipotency during culture. Furthermore, fMSC ECM improved the proliferation (∼ 2.2 ×), size (19.6 ± 11.9 µm vs 30.2 ± 14.5 µm) and differentiation potential in late-passaged aMSCs compared to TCPS. In conclusion, we have established fMSC ECM as a promising cell culture platform for ex vivo expansion of aMSCs.


Assuntos
Células-Tronco Embrionárias/citologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Materiais Biomiméticos , Proliferação de Células/fisiologia , Células Cultivadas , Células-Tronco Embrionárias/metabolismo , Matriz Extracelular/metabolismo , Humanos , Imunofenotipagem
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