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Traditional Vietnamese herbal species were examined for their antimicrobial activity and disease resistance in whiteleg shrimp. In-vitro screening, the extracts of ten herbs were conducted to test the inhibition ability against Vibrio parahaemolyticus, causing acute hepatopancreatic necrosis disease. The results showed that five out of ten herbal species, including Pithecellobium dulce, Melaleuca leucadendron, Eucalyptus globulus, Mimosa pirga, and Hibiscus sabdariffa displayed potent antibacterial activity. Besides, three types of extracts of H. sabdariffa, E. globulus, and M. pirga were coated to the pellet feed at a concentration of 1%. After 30 days of feeding, the whiteleg shrimp (Penaeus vannamei) were challenged by V. parahaemolyticus through immersion. The growth performance (such as growth rate in length and weight, survival rate), hematological parameters of total hemocytes (THC), hyaline hemocytes (HC), and granulocytes (GC), and hepatopancreas recovery under the treatments with herbal extracts of the whiteleg shrimp were significantly enhanced as compared with the control (without herbal extract). The mortality and the bacterial density in the hepatopancreas of shrimp decreased. Specifically, the mortality of shrimp in the treatment supplemented with the methanol extract of H. sabdariffa was the lowest, followed by M. pirga and E. globulus. The experimental results also indicated that H. sabdariffa, E. globulus, and M. pirga could improve immune parameters and disease resistance; therefore, they should be employed in sustainable shrimp, practical farming. [ABSTRACT FROM AUTHOR]

Three newly designed benzene-core photonic crystal fibers (BC-PCFs) can optimize both chromatic dispersion and attenuation characteristics simultaneously for the most efficient application to generate supercontinuum. The nonlinear characteristics of BC-PCFs with the circular lattice (CL), square lattice (SL), and hexagonal lattice (HL) are analyzed numerically to select the optimal PCF. The three optimized structures: #CBF1, #SBF2, and #HBF3 are intended for supercontinuum generation (SCG) in an all-normal dispersion regime. The obtained results demonstrated that although #HBF3 fiber has a larger effective mode area and attenuation than #CBF1, #SBF2 fibers, the dispersion curve of #HBF3 is flattest and closest to the zero-dispersion curve in the wavelength region of 0.8–2.0 µm hence it has the highest efficiency for SCG. These PCFs are capable of coherent octave-wide SCG in the 0.66–1.53 µm, 0.71–1.76 µm, and 0.71–1.82 µm wavelength ranges with low peak power of 0.45 kW and 40 fs pulses coupled to the core. Those fibers are the real objects for the sources of all-fiber supercontinuum, which can be substituted for glass core fibers because the nonlinearity of silica is lower than that of benzene. The proposed remedy can lead to new low-cost all-fiber optical systems. [ABSTRACT FROM AUTHOR]

Objective: The aim of the study was to describe clinical and biological characteristics and thrombotic relapses of patients diagnosed with antiphospholipid syndrome (APS) after the age of 65 years, in comparison with patients diagnosed with APS before 65. Methods: This retrospective multicenter study was performed to 2005 from 2017 and included patients diagnosed with APS after the age of 65 years, in accordance with Sydney criteria. We compared these patients with APS patients diagnosed before the age of 65 years, and with control thrombotic patients older than 65 years. Results: Fifty-eight APS patients over the age of 65 years were compared to 127 APS patients aged less than 65 and to 58 controls. In elderly APS versus younger APS, there was a male predominance (58.6% vs 36.2% p =.001); myocardial infarction and lower limb deep vein thrombosis (LLDVT) were more frequent in elderly, respectively, 12.1% versus 1.6% (p =.005), and 44.8% versus 29.9% (p =.048). Anticardiolipin antibody (aCL) IgM was more frequently found in old patients compared to younger patients (33.9% vs 18.1%, p =.02), contrary to lupus anticoagulant (LAC) (52.8% vs 66.9%, p =.02). Older patients were more often diagnosed with single positive APS (82.8% vs 59.8% p =.002). The thrombotic relapse free survival was lower in elderly APS patients (p =.044) compared to younger APS. Elderly APS patients had more recurrent arterial and venous thrombosis (p =.03) and had poorer overall survival (p =.004) than elderly controls. Conclusion: In this study, APS was different in patients aged more than 65 years, with a male predominance and more myocardial infarctions and LLDVT at diagnosis. Single antiphopholipid positivity and aCL IgM were more frequent in older patients. Older patient with APS had more thrombotic recurrence during follow-up. Compared to elderly controls, elderly APS patients had more thrombosis recurrences and poorer survival. [ABSTRACT FROM AUTHOR]

Three types of hollow-core photonic crystal fibers (HC-PCFs) of optimized design with respect to both chromatic dispersion and loss were used to investigate supercontinuum generation (SCG). The optical properties of HC-PCFs filled with nitrobenzene (C6H5NO2) with the circular lattice (CL), square lattice (SL), and hexagonal lattice (HL) are analyzed to choose the optimal fiber. As a result, the three optimized structures: #CF1 (lattice constant (Λ) of 1.0 μm, filling factor (f1) of 0.65, and core diameter (Dc) of 1.285 µm), #SF2 (Λ = 1.0 μm, f1 = 0.7, and Dc = 1.23 µm), #HF3 (Λ = 1.0 μm, f1 = 0.45, and Dc = 1.505 µm) with flat and close to zero chromatic dispersion curve in the investigated wavelength region, have the values of chromatic dispersion − 10 ps.nm−1.km−1 at 1.15 μm, − 7.7 ps.nm−1.km−1 at 1.23 μm, and − 3.0 ps nm−1 km−1 at the 1.55 μm pump wavelength, respectively are intended for SCG in an all-normal dispersion regime. We demonstrate the possibility of coherent octave-wide SCG in the wavelength range of 0.72 ÷ 1.7 μm, 0.74 ÷ 1.77 μm, and 0.83 ÷ 2.36 μm with 90 fs pulses and 10 pJ of low energy in-coupled into the considered fibers core. The obtained results show that SCG with HL-PCFs has the highest efficiency, although all fibers are examined with the same input energy. Especially, the supercontinuum (SC) spectral bandwidth is independent of the type of lattice at the pump energy of 1.57 pJ, and this can be seen as a limitation between the pure self-phase modulation and other nonlinear processes contributing to SCG. [ABSTRACT FROM AUTHOR]

This work presents the OH-initiated oxidation kinetics of 1,4-cyclochexadiene (1,4-CHD). The temperature dependence of the reaction was investigated by utilizing a laser flash photolysis flow reactor and laser-induced fluorescence (LPFR/LIF) technique over the temperature range of 295–438 K and a pressure of ∼50 torr. The kinetics of the reaction was followed by measuring the LIF signal of OH radicals near 308 nm. The reaction of OH radicals with 1,4-CHD exhibited a clear negative temperature dependence. To discern the role of various channels, ab initio and RRKM-based ME calculations (RRKM-ME) were performed over temperatures of 200–2000 K and pressures of 0.76–7600 torr. The computed energy profile revealed that the reaction proceeds via the formation of a pre-reaction van der Waals complex at the entrance channel. The complex was found to be more stable than that usually seen in other alkenes + OH reactions. Both the addition channel and the abstraction reaction of allylic hydrogen were found to have negative energy barriers. Interestingly, the abstraction reaction exhibited a negative temperature dependence at low temperatures and contributed significantly (∼37%) to the total rate coefficients even under atmospheric conditions. At T ≥ 900 K, the reaction was found to proceed exclusively (>95%) via the abstraction channel. Due to the competing channels, the reaction of OH radicals with 1,4-CHD displays complicated kinetic behaviours, reflecting the salient features of the energy profile. The role of competing channels was fully characterized by our kinetic model. The calculated rate coefficients showed excellent agreement with the available experimental data. [ABSTRACT FROM AUTHOR]

Background: Maple sirup urine disease (MSUD) is an autosomal recessive inherited metabolic disorder. The disease‐causing mutations can affect the BCKDHA, BCKDHB, and DBT genes encoding for the E1α, E1β, and E2 subunits of the multienzyme branched‐chain α‐keto acid dehydrogenase (BCKDH) complex. In the present study, novel pathogenic variants in BCKDHB and DBT genes were identified in three Vietnamese families with MSUD. Methods: Three newborn patients from three unrelated Vietnamese families were diagnosed with MSUD at the Metabolic Clinic, National Hospital of Pediatrics. Blood samples of 11 relatives from two generations of the three families diagnosed with MSUD were analyzed using exome and Sanger sequencing analyses. Results: Novel pathogenic variants in BCKDHB (c.1103C>T, c.989A>G, and c.704G>A), and DBT (c.263_265delAAG) genes were identified in three pediatric patients with MSUD. Conclusions: We have identified novel pathogenic variants in the MSUD‐related genes in the pedigree of the three patient's families. Our findings expand the mutational spectrum of MSUD and provide the scientific basis for genetic counseling for the patient's families. [ABSTRACT FROM AUTHOR]

Importance: Monitoring the results of selective laser trabeculoplasty (SLT) on intraocular pressure (IOP) using a home rebound tonometry. Background: To evaluate the role of Icare HOME tonometry in open‐angle glaucoma patients being treated with SLT. Design: A clinic‐based prospective case study. Participants: Fourteen eyes from 14 patients diagnosed with primary open‐angle glaucoma were recruited. Methods: The trabecular meshwork of each eye was treated 360° with a frequency‐doubled Q‐switched Nd:YAG laser. IOP was measured four times a day for a week before and after SLT. On the day of SLT, the patients were required to measure the IOP in the evening to record any IOP spikes. Main Outcome Measures: The use of Icare HOME in following up patients post‐laser trabeculoplasty without the need for clinic attendance. Results: Icare HOME recorded a significant reduction of 5.12 mmHg in the mean IOP post‐SLT (95% confidence interval [CI] 3.75‐6.50 mmHg, P <.001). The maximum IOP was also reduced by 6.14 mmHg (95% CI 3.07‐9.21, P <.001) with no IOP spikes recorded post‐SLT. There was a reduction in IOP fluctuation post‐SLT by 1.07 mmHg (95% CI 0.24‐1.89 mmHg, P =.021). No adverse effects for using the Icare HOME were reported by the study participants. Conclusions and Relevance: This methodology could be highly useful for facilitating safe follow‐up of patients residing in remote and rural areas, thus reducing healthcare cost with better information on IOP. [ABSTRACT FROM AUTHOR]

Introduction: We investigated the effects of lower back pain (LBP) on measures of pain, disability, and function in highly symptomatic hip OA patients receiving intra-articular steroid injection (IASI) therapy. We also investigated the effect of radiographic severity of hip OA for comparison to LBP. Methods: 97 consenting subjects with symptomatic hip OA presenting for IASI were evaluated at baseline, assessed over an 8-week period, and followed at least 1 year later for new arthroplasty. At baseline and 8 weeks follow-up patient demographics, presence/absence of back pain, physical function tests, a single anteroposterior pelvis x-ray, and subjective scores of pain, stiffness and function (VAS and WOMAC) were collected. We also followed which subjects proceeded to obtain total hip arthroplasty in the examined hip. Results: Cohorts with LBP reported significantly worse scores for all of VAS pain and WOMAC questionnaires but showed no difference in ROM and were not more likely to proceed to arthroplasty. Cohorts with severe radiographic OA had significantly worsened scores for stiffness (χ2 = 6.74, p = 0.009), decreased ROM (p < 0.01), and were more likely to proceed to arthroplasty (χ2 = 9.79, p = 0.044). Discussion: Back pain has a substantial effect on clinical parameters relevant to assessment of severity of hip OA, especially self-reported pain and function. This finding highlights LBP as a significant confounding factor in hip OA patient assessments and will inform future studies to determine the most effective treatment strategies for hip OA patients. [ABSTRACT FROM AUTHOR]

The efficiency with which the anaerobic fungi (phylum Neocallimastigomycota) degrade plant biomass is well-recognized and in recent years has received renewed interest. To further understand the biological mechanisms that are utilized by the rumen anaerobic fungi to break down lignocellulose, we have used a transcriptomic approach to examine carbohydrate digestion by Neocallimastix frontalis, Piromyces rhizinflata, Orpinomyces joyonii, and Anaeromyces mucronatus cultured on several carbon sources. The number of predicted unique transcripts ranged from 6,633 to 12,751. Pfam domains were identified in 62–70% of the fungal proteins and were linked to gene ontology terms to infer the biological function of the transcripts. Most of the predicted functions are consistent across species suggesting a similar overall strategy evolved for successful colonization of the rumen. However, the presence of differential profiles in enzyme classes suggests that there may be also be niche specialization. All fungal species were found to express an extensive array of transcripts encoding carbohydrate active enzymes (CAZymes) ranging from 8.3 to 11.3% of the transcriptome. CAZyme families involved in hemicellulose digestion were the most abundant across all four fungi. This study provides additional insight into how anaerobic fungi have evolved to become specialists at breaking down the plant cell wall in the complex and, strictly anaerobic rumen ecosystem. [ABSTRACT FROM AUTHOR]

A dual-band circularly polarized four-arm Spidron fractal antenna is proposed for Ku-band satellite communication. The dual-band characteristic is realized using two-crossed dipole antennas of different lengths. Each dipole arm includes a Spidron fractal patch to generate circular polarization and a printed meander-line to reduce the size. The proposed antenna is fed by a 50-coaxial cable, and a conducting cavity is utilized to obtain a directional circularly polarized radiation pattern. The experiments demonstrate that the fabricated antenna exhibits −10 dB reflection bandwidths ranging from 10.75 GHz to 12.65 GHz and from 13.33 GHz to more than 15 GHz with a broad 3 dB axial ratio bandwidth covering a frequency range of 10.66–14.46 GHz. The measured peak gains are 8.76 dBic in the lower band and 7.43 dBic in the upper band. [ABSTRACT FROM PUBLISHER]

This study was conducted to estimate the prevalence of Salmonella spp. and their antimicrobial susceptibilities on poultry and swine farms, sampled in 2 regions in Central Vietnam. A total of 67 poultry farms and 46 swine farms were sampled in a period of 5 months (from September 2012 to January 2013). Salmonella spp. was prevalent in 46.3% and 71.7% of poultry and swine farms, respectively. Altogether, 99 non-typhoidal Salmonella were isolated and the most common serovars were Salmonella Weltevreden (19%), followed by Salmonella Typhimurium (12%) and Salmonella 4,[5],12:i:- (11%). Overall, 71 of 99 (72%) Salmonella isolates were resistant to at least one of the 14 antimicrobial agents tested. Both in poultry and swine farms, high levels of resistance were observed for ampicillin, chloramphenicol, ciprofloxacin, sulphamethoxazole and tetracycline. The presence of Salmonella isolates from poultry and swine farms which were resistant to different classes of antimicrobials suggests that alternative control measures to antimicrobials should be implemented. Moreover, an effective policy should be promoted to encourage a prudent use of these agents in animal farming in Vietnam. [ABSTRACT FROM AUTHOR]

We describe the results of a study to determine the prevalence and characteristics of cytomegalovirus (CMV) retinitis among HIV-infected patients in Vietnam. We conducted a cross-sectional prospective study of patients with CD4 lymphocyte count ≤100 cells/mm3 recruited from public HIV clinics. The diagnosis was made by a trained ophthalmologist using slit lamp biomicroscopy and corroborated on fundus photography. A total of 201 patients were screened. The median age was 32 years, 77% were men, median CD4 count was 47 cells/mm3, and 62% were on antiretroviral treatment. Prevalence of CMV retinitis was 7% (14/201, 95% CI 4–11%). CMV retinitis was not associated with age, gender, injection drug use, CD4 count, WHO clinical stage, or antiretroviral treatment status. Blurring of vision and reduced visual acuity <20/40 were associated with CMV retinitis, but only 29% of patients with the diagnosis reported blurry vision and only 64% had abnormal vision. On multivariate analysis, the sole predictor for CMV retinitis was decreased visual acuity (OR 22.8, p < 0.001). In Ho Chi Minh City, CMV retinitis was found in 7% of HIV-infected patients with low CD4. HIV-infected patients with a CD4 count <100/mm3 or who develop blurring of vision in Vietnam should be screened for CMV retinitis. [ABSTRACT FROM PUBLISHER]

We performed chromatin immunoprecipitation (ChIP) analyses of developmentally staged solid tissues isolated from wild-type and p53-null mice to determine specific histone N-terminal modifications, histone-modifying proteins, and transcription factor interactions at the developmental repressor region (-850) and core promoter of the hepatic tumor marker alpha-fetoprotein (AFP) gene. Both repression of AFP during liver development and silencing in the brain, where AFP is never expressed, are associated with dimethylation of histone H3 lysine 9 (DiMetH3K9) and the presence of heterochromatin protein 1 (HP1). These heterochromatic markers remain localized to AFP during developmental repression but spread to the upstream albumin gene during silencing. Developmentally regulated decreases in levels of acetylated H3 (AcH3K9) and H4 (AcH4) and of di- and trimethylated H3K4 (DiMetH3K4 and TriMetH3K4) occur at both the core promoter and distal repressor regions of AFP. Hepatic expression of AFP correlates with FoxA interaction at the repressor region and the binding of RNA polymerase II and TATA-binding protein to the core promoter, p53 acts as a developmental repressor of AFP in the liver by binding to chromatin, excluding FoxA interaction and targeting mSin3A/HDAC1 to the distal repressor region, p53-null mice exhibit developmentally delayed AFP repression, concomitant with acetylation of H3K9, methylation of H3K4, and loss of DiMetH3K9, mSin3A/ HDAC1, and HP1 interactions. [ABSTRACT FROM AUTHOR]

We purified the oncoprotein SnoN and found that it functions as a corepressor of the tumor suppressor p53 in the regulation of the hepatic α-fetoprotein (AFP) tumor marker gene. p53 promotes SnoN and histone deacetylase interaction at an overlapping Smad binding, p53 regulatory element (SBE/p53RE) in AFP. Comparison of wild-type and p53-null mouse liver tissue by using chromatin immunoprecipitation (CHIP) reveals that the absence of p53 protein correlates with the disappearance of SnoN at the SBE/p53RE and loss of AFP developmental repression. Treatment of AFP-expressing hepatoma cells with transforming growth factor-βl (TGF-β1) induced SnoN transcription and Smad2 activation, concomitant with AFP repression. ChIP assays show that TGF-β1 stimulates p53, Smad4, P-Smad2 binding, and histone H3K9 deacetylation and methylation, at the SBE/p53RE. Depletion, by small interfering RNA, of SnoN and/or p53 in hepatoma cells disrupted repression of AFP transcription. These findings support a model of cooperativity between p53 and TGF-β effectors in chromatin modification and transcription repression of an oncodevelopmental tumor marker gene. [ABSTRACT FROM AUTHOR]

A dual‐band circularly‐polarised antenna implemented on a single substrate is proposed for Ku‐band satellite communication. A microstrip‐fed Spidron fractal patch is utilised to achieve dual‐band resonance and circular polarisation. The proposed antenna, with dimensions of 50 × 50 × 1.52 mm3, has also been fabricated and tested. The measured −10 dB reflection bandwidths are 8.7% (11.44–12.48 GHz) and 6.6% (13.47–14.39 GHz), exhibiting a small resonant frequency ratio of 1.15. The 3 dB axial ratio bandwidths for the lower band and the upper band are 2.96 and 1.68%, respectively. [ABSTRACT FROM AUTHOR]