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1.
Proc Natl Acad Sci U S A ; 120(27): e2219489120, 2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37364110

RESUMEN

Most paleoclimate studies of Mainland Southeast Asia hydroclimate focus on the summer monsoon, with few studies investigating rainfall in other seasons. Here, we present a multiproxy stalagmite record (45,000 to 4,000 years) from central Vietnam, a region that receives most of its annual rainfall in autumn (September-November). We find evidence of a prolonged dry period spanning the last glacial maximum that is punctuated by an abrupt shift to wetter conditions during the deglaciation at ~14 ka. Paired with climate model simulations, we show that sea-level change drives autumn monsoon rainfall variability on glacial-orbital timescales. Consistent with the dry signal in the stalagmite record, climate model simulations reveal that lower glacial sea level exposes land in the Gulf of Tonkin and along the South China Shelf, reducing convection and moisture delivery to central Vietnam. When sea level rises and these landmasses flood at ~14 ka, moisture delivery to central Vietnam increases, causing an abrupt shift from dry to wet conditions. On millennial timescales, we find signatures of well-known Heinrich Stadials (HS) (dry conditions) and Dansgaard-Oeschger Events (wet conditions). Model simulations show that during the dry HS, changes in sea surface temperature related to meltwater forcing cause the formation of an anomalous anticyclone in the Western Pacific, which advects dry air across central Vietnam, decreasing autumn rainfall. Notably, sea level modulates the magnitude of millennial-scale dry and wet phases by muting dry events and enhancing wet events during periods of low sea level, highlighting the importance of this mechanism to autumn monsoon variability.

2.
RNA Biol ; 21(1): 1-8, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38836544

RESUMEN

Production and storage of synthetic mRNA can introduce a variety of byproducts which reduce the overall integrity and functionality of mRNA vaccines and therapeutics. mRNA integrity is therefore designated as a critical quality attribute which must be evaluated with state-of-the-art analytical methods before clinical use. The current study first demonstrates the effect of heat degradation on transcript translatability and then describes a novel enzymatic approach to assess the integrity of conventional mRNA and long self-amplifying mRNA. By first hybridizing oligo-T to the poly(A) tail of intact mRNA and subsequently digesting the unhybridized RNA fragments with a 3'-5' exoribonuclease, individual nucleotides can be selectively released from RNA fragments. The adenosine-based fraction of these nucleotides can then be converted into ATP and detected by luminescence as a sensitive indicator of mRNA byproducts. We developed a polynucleotide phosphorylase (PNPase)-based assay that offers fast and sensitive evaluation of mRNA integrity, regardless of its length, thus presenting a novel and fully scalable alternative to chromatographic-, electrophoresis-, or sequencing-based techniques.


Asunto(s)
Polirribonucleótido Nucleotidiltransferasa , ARN Mensajero , ARN Mensajero/genética , ARN Mensajero/metabolismo , Polirribonucleótido Nucleotidiltransferasa/metabolismo , Polirribonucleótido Nucleotidiltransferasa/genética , Humanos , Oligonucleótidos/metabolismo , Estabilidad del ARN
3.
BMC Infect Dis ; 24(1): 508, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773469

RESUMEN

Chromobacterium violaceum is a rare but severe and often fatal cause of disease in humans. We present 2 clinical cases of sepsis and skin abscesses / cellulitis caused by C. violaceum seen in a referral hospital for infectious diseases in Vietnam. Both patients survived, but appropriate antibiotic treatment was only installed after culture of the organism. We reviewed and summarised the characteristics of C. violaceum infection and treatment.


Asunto(s)
Antibacterianos , Chromobacterium , Infecciones por Bacterias Gramnegativas , Femenino , Humanos , Antibacterianos/uso terapéutico , Celulitis (Flemón)/microbiología , Celulitis (Flemón)/tratamiento farmacológico , Chromobacterium/aislamiento & purificación , Chromobacterium/efectos de los fármacos , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Infecciones por Bacterias Gramnegativas/microbiología , Sepsis/microbiología , Sepsis/tratamiento farmacológico , Vietnam , Niño , Adolescente
4.
BMC Infect Dis ; 24(1): 622, 2024 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-38910264

RESUMEN

BACKGROUND: Respiratory infections have long been recognized as a primary cause of acute exacerbation of chronic obstructive pulmonary disease (AE-COPD). Additionally, the emergence of antimicrobial resistance has led to an urgent and critical situation in developing countries, including Vietnam. This study aimed to investigate the distribution and antimicrobial resistance of bacteria in patients with AE-COPD using both conventional culture and multiplex real-time PCR. Additionally, associations between clinical characteristics and indicators of pneumonia in these patients were examined. METHODS: This cross-sectional prospective study included 92 AE-COPD patients with pneumonia and 46 without pneumonia. Sputum specimens were cultured and examined for bacterial identification, and antimicrobial susceptibility was determined for each isolate. Multiplex real-time PCR was also performed to detect ten bacteria and seven viruses. RESULTS: The detection rates of pathogens in AE-COPD patients with pneumonia were 92.39%, compared to 86.96% in those without pneumonia. A total of 26 pathogenic species were identified, showing no significant difference in distribution between the two groups. The predominant bacteria included Klebsiella pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae, followed by Acinetobacter baumannii and Streptococcus mitis. There was a slight difference in antibiotic resistance between bacteria isolated from two groups. The frequency of H. influenzae was notably greater in AE-COPD patients who experienced respiratory failure (21.92%) than in those who did not (9.23%). S. pneumoniae was more common in patients with stage I (44.44%) or IV (36.36%) COPD than in patients with stage II (17.39%) or III (9.72%) disease. ROC curve analysis revealed that C-reactive protein (CRP) levels could distinguish patients with AE-COPD with and without pneumonia (AUC = 0.78). CONCLUSION: Gram-negative bacteria still play a key role in the etiology of AE-COPD patients, regardless of the presence of pneumonia. This study provides updated evidence for the epidemiology of AE-COPD pathogens and the appropriate selection of antimicrobial agents in Vietnam.


Asunto(s)
Antibacterianos , Bacterias , Farmacorresistencia Bacteriana , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/microbiología , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Estudios Transversales , Vietnam/epidemiología , Estudios Prospectivos , Masculino , Femenino , Anciano , Persona de Mediana Edad , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Bacterias/aislamiento & purificación , Bacterias/efectos de los fármacos , Bacterias/clasificación , Bacterias/genética , Neumonía Bacteriana/microbiología , Neumonía Bacteriana/tratamiento farmacológico , Neumonía Bacteriana/epidemiología , Pruebas de Sensibilidad Microbiana , Esputo/microbiología , Anciano de 80 o más Años , Neumonía/microbiología , Neumonía/tratamiento farmacológico , Neumonía/epidemiología
5.
J Gen Intern Med ; 38(1): 49-56, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35484365

RESUMEN

BACKGROUND: Some antihyperglycemic drugs can reduce cardiovascular events, slow the progression of kidney disease, and prevent death, but they are more expensive than older drugs. OBJECTIVES: (1) To estimate trends in use of antihyperglycemic drugs by cost; (2) to examine use of high-cost drugs by race/ethnicity, income, and insurance status DESIGN: Cross-sectional analysis of the 2003-2018 National Health and Nutrition Examination Survey PARTICIPANTS: US adults ≥18 years with type 2 diabetes EXPOSURES: Race/ethnicity, income, and insurance status MAIN MEASURES: Low-cost noninsulin medications included any drugs that had at least one generic version approved by the Food and Drug Administration. Human regular, NPH, and premixed NPH/regular 70/30 insulins were classified as low-cost. All other noninsulin medications and insulins were considered high-cost KEY RESULTS: The sample included 7,394 patients. Prevalence of use of low-cost noninsulin drugs increased from 37% in 2003-2004 to 52% in 2017-2018. Use of high-cost noninsulin drugs decreased from 2003-2004 to 2013-2014 and then slowly increased. Use of low-cost insulin decreased from 7 to 2% while high-cost insulin rose from 4 to 16%. In multivariable analysis, non-White patients had 25-35% lower odds of receiving high-cost drugs than non-Hispanic Whites. Health insurance was associated with more than twice the odds of having high-cost drugs compared to no insurance. Patients with higher HbA1c or moderate obesity were also more likely to use high-cost drugs. Sex, income, and insurance type were not associated with receipt of high-cost drugs. CONCLUSIONS: There was a shift in utilization from high- to low-cost noninsulin drugs, but since 2013-2014 the trend has slowly reversed with increased use of newer, more expensive drug classes. High-cost insulin analogs have almost completely replaced lower cost human insulins. Disparities in receipt of diabetes drugs by race/ethnicity and insurance must be addressed to ensure that cost is not a barrier for disadvantaged populations.


Asunto(s)
Diabetes Mellitus Tipo 2 , Hipoglucemiantes , Humanos , Adulto , Estados Unidos/epidemiología , Hipoglucemiantes/uso terapéutico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/epidemiología , Encuestas Nutricionales , Estudios Transversales , Insulina/uso terapéutico
6.
Molecules ; 28(3)2023 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-36771166

RESUMEN

Fifteen push-pull dyes comprising the tetracyclic polyaromatic pyrene have been designed and synthesized. The optical properties of the fifteen dyes have been examined in twenty-two solvents of different polarities. Surprisingly, contrarily to what is classically observed for push-pull dyes of D-π-A structures, a negative solvatochromism could be found for numerous dyes. The photoluminescence and thermal properties of the dyes were also examined. Theoretical calculations were carried out to support the experimental results.

7.
Softw Qual J ; : 1-69, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38625270

RESUMEN

Integration of machine learning (ML) components in critical applications introduces novel challenges for software certification and verification. New safety standards and technical guidelines are under development to support the safety of ML-based systems, e.g., ISO 21448 SOTIF for the automotive domain and the Assurance of Machine Learning for use in Autonomous Systems (AMLAS) framework. SOTIF and AMLAS provide high-level guidance but the details must be chiseled out for each specific case. We initiated a research project with the goal to demonstrate a complete safety case for an ML component in an open automotive system. This paper reports results from an industry-academia collaboration on safety assurance of SMIRK, an ML-based pedestrian automatic emergency braking demonstrator running in an industry-grade simulator. We demonstrate an application of AMLAS on SMIRK for a minimalistic operational design domain, i.e., we share a complete safety case for its integrated ML-based component. Finally, we report lessons learned and provide both SMIRK and the safety case under an open-source license for the research community to reuse.

8.
AIDS Care ; 34(4): 430-439, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-33715537

RESUMEN

This mixed methods study aimed to evaluate the feasibility and preliminary efficacy of a fully automated, interactive smartphone-delivered intervention for smoking cessation among people living with HIV in Cambodia. We used the explanatory sequential design, with a pilot two-group single-blind randomized controlled trial (N = 50) followed by in-depth interviews with all trial participants. In the trial, participants were randomized to Standard Care (SC) or Automated Messaging (AM) group. SC comprised brief advice to quit and self-help materials. AM consisted of the SC components plus a fully automated smartphone-based treatment program that involved interactive and tailored proactive messaging for 2 months. Results showed that the AM approach was highly feasible and efficacious. Feasibility was supported by high rates of treatment engagement (e.g., 81% of delivered messages and assessments were read or completed) and high retention (96%) through the 2-month follow-up. Biochemically verified point prevalence abstinence at follow-up was 40% for the AM group and 8% for the SC group (relative risk: 5.0, 95% confidence interval: 1.2, 20.5). Being able to avoid other smokers, having coping skills, and having social/familial support contributed to successful abstinence. The AM program has the potential for wide-scale implementation in Cambodia and other low-income countries.


Asunto(s)
Infecciones por VIH , Cese del Hábito de Fumar , Envío de Mensajes de Texto , Pueblo Asiatico , Infecciones por VIH/terapia , Humanos , Proyectos Piloto , Método Simple Ciego , Cese del Hábito de Fumar/métodos
9.
Am J Otolaryngol ; 43(3): 103397, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35210111

RESUMEN

PURPOSE: To evaluate the efficiency of a biodegradable gel containing hyaluronic acid and berberine hydrochloride in endoscopic sinus surgery. METHODS: Sixty-six chronic rhinosinusitis patients with or without nasal polyps who underwent bilateral endoscopic sinus surgery (ESS) were randomly received a biodegradable gel containing hyaluronic acid and berberine hydrochloride or merocel in both middle meatal spacers at the end procedure of ESS. Lund-Kennedy endoscopic score (LKES) was used to examine status of nasal cavity on preoperative day and postoperative day 1 to 7. The LKES ratio was calculated as the LKES on postoperative day divided into the LKES on preoperative day. Visual analogue score (VAS) was used to assess patient's status from the first postoperative day to the hospital discharge day. The average VAS during hospital stays was calculated by the sum of VAS in each examination day divided into the number of examined day. The LKES ratio, the average of VAS during hospital stays and length of hospitalized day of the patients were used as clinical outcome indices in early stage after surgery. A general linear model adjusted for confounding factors was used for data analysis. RESULTS: Adjusted mean of LKES ratio were lower in group used biodegrable gel of hyaruloic acid and berberin hydrochlode (study group) than those in merocele group in the postoperative day 1 to day 7. However, significant difference was found in the adjusted mean of LKES ratio on the postoperative day 2 to 6. Similarly, the adjusted mean of VAS during hospital stays and length of hospitalized day after surgery in study group were significantly decreased as compared with those in merocele group. CONCLUSIONS: Biodegradable material containing hyaluronic acid and berberine hydrochloride was more effective than merocel in length of hospital stay, post-operative symptoms, and sinus cavity's status in early stage after ESS.


Asunto(s)
Berberina , Pólipos Nasales , Rinitis , Sinusitis , Enfermedad Crónica , Endoscopía/métodos , Humanos , Ácido Hialurónico , Pólipos Nasales/cirugía , Estudios Prospectivos , Rinitis/diagnóstico , Rinitis/cirugía , Sinusitis/diagnóstico , Sinusitis/cirugía , Resultado del Tratamiento
10.
Chem Biodivers ; 19(7): e202101026, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35698444

RESUMEN

Worldwide, medicinal plants have been known for economic and geographical advantages, thus possibly holding potentiality against dengue hemorrhagic fever. The methanol/water extracts from different parts of fourteen Vietnam-based plant species were subjected for experimental screening on anti-dengue activity using baby hamster kidney cells (BHK21) and plaque reduction neutralisation test (PRNT). Firstly, the methanol/water extracts were tested against serotype dengue virus DENV-1. Seven out from nineteen extracts show the PRNT50 values less than 31.25 µg/mL. Four of the above extracts namely from Euphorbia hirta, Cordyline terminalis, Carica papaya, and Elaeagnus latifolia were chosen for testing against the serotype DENV-2. All of them exhibit good activity with the PRNT50 values less than 31.25 µg/ml, which were further fractionated to obtain hexane, ethyl acetate and butanol fractions. Anti-dengue virus activity of the fractions against four serotypes DENV-1, -2, -3 and -4 was evaluated. As results, the ethyl acetate fraction of Elaeagnus latifolia is highly active against all four serotype viruses. The structural formulae of its nine constituents were input for molecular docking simulation. The docking-based order for static inhibitability is 6-3L6P>7-3L6P>9-3L6P>2-3L6P>3-3L6P≈5-3L6P>9-3L6P>1-3L6P>8-3L6P; QSARIS-based analysis reveals the biocompatibility of the most promising ligands (4-7); ADMET-based analysis expects their pharmacological suitability. Exceptional finding on 2-3LKW hydrophilic interaction at Lys43 (with the associated Gibbs free energy of -10.3 kcal mol-1 ) raises an open explanation for inhibitory effects. The results encourage further investigations for more in-depth mechanisms and drug development, such as in vitro enzyme assays or in vitro clinical trials with natural substances from E. latifolia.


Asunto(s)
Plantas Medicinales , Antivirales/química , Antivirales/farmacología , Pueblo Asiatico , Humanos , Metanol , Simulación del Acoplamiento Molecular , Plantas Medicinales/química , Vietnam , Agua
11.
Hemoglobin ; 46(4): 233-239, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35993587

RESUMEN

Vietnam has a high thalassemia burden. We collected blood samples from 5880 pregnant Vietnamese women during prenatal health checks to assess thalassemia carrier frequency using combined gap-polymerase chain reaction (gap-PCR) and targeted next-generation sequencing (NGS). Thalassemia carriers were identified with prevalence of 13.13% (772), including 7.82% (460) carriers of α-thalassemia (α-thal), 5.31% (312) carriers of ß-thalassemia (ß-thal), and 0.63% (37) concurrent α-/ß-thal carriers. Deletional mutations (368) accounted for 80.0% of α-thal carriers, of which, --SEA (Southeast Asian) (n = 254; 55.0%) was most prevalent, followed by the -α3.7 (rightward) (n = 66; 14.0%) and -α4.2 (leftward) (n = 45; 9.8%) deletions. Hb Westmead (HBA2: c.369C>G) (n = 53) and Hb Constant Spring (Hb CS or HBA2: c.427T>C) (in 28) are the two most common nondeletional α-globin variants, accounting for 11.5 and 6.0% of α-thal carriers. We detected 11 different ß-thal genotypes. Hb E (HBB: c.79G>A) (in 211) accounted for 67.6% of ß-thal carriers. The most common ß-thal genotypes were associated with mutations at codon 17 (A>T) (HBB: c.52A>T), codons 41/42 (-TTCT) (HBB: c.126_129delCTTT), and codon 71/72 (+A) (HBB: c.217_218insA) (prevalence 0.70%, 0.68%, and 0.2%, respectively). Based on mutation frequencies calculated in this study, estimates of 5021 babies in Vietnam are affected with clinically severe thalassemia annually. Our data suggest a higher thalassemia carrier frequency in Vietnam than previously reported. We established that combining NGS with gap-PCR creates an effective large-scale thalassemia screening method that can detect a broad range of mutations.


Asunto(s)
Talasemia alfa , Talasemia beta , Femenino , Humanos , Embarazo , Talasemia beta/diagnóstico , Talasemia beta/epidemiología , Talasemia beta/genética , Globinas beta/genética , Mujeres Embarazadas , Vietnam/epidemiología , Frecuencia de los Genes , Talasemia alfa/diagnóstico , Talasemia alfa/epidemiología , Talasemia alfa/genética , Reacción en Cadena de la Polimerasa , Mutación , Codón , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento
12.
Artículo en Inglés | MEDLINE | ID: mdl-35422534

RESUMEN

High-fidelity cardiac models using attribute-rich finite element based models have been developed to a very mature stage. However, such finite-element based approaches remain time consuming, which have limited their clinical use. There remains a need for alternative methods for novel cardiac simulation methods of capable of high fidelity simulations in clinically relevant time frames. Surrogate models are one approach, which traditionally use a data-driven approach for training, requiring the generation of a sufficiently large number of simulation results as the training dataset. Alternatively, a physics-informed neural network can be trained by minimizing the PDE residuals or energy potentials. However, this approach does not provide for a general method to easily using existing finite element models. To address these challenges, we developed a hybrid approach that seamlessly bridged a neural network surrogate model with a differentiable finite element domain representation (NNFE). Given its importance in cardiac simulations, we applied this approach to simulations of the hyperelastic mechanical behavior of ventricular myocardium from recent 3D kinematic constitutive model (J Mech Behav Biomed Mater, 2020 doi: 10.1016/j.jmbbm.2019.103508). We utilized cuboidal domain and conducted numerical studies of individual myocardium specimens discretized by a finite element mesh and assigned with experimentally obtained myofiber architectures. Both parameterized Dirichlet and Neumann boundary conditions were studied. We developed a second-order Newton optimization method, instead of using stochastic gradient descent method, to train the neural network efficiently. The resulting trained neural network surrogate model demonstrated excellent agreement with the corresponding 'ground truth' finite element solutions over the entire physiological deformation range. More importantly, the NNFE approach provided a significantly decreased computational time for a range of finite element mesh sizes for online predictions. For example, as the finite element mesh sized increased from 2744 to 175615 elements the NNFE computational time increased from 0.1108 s to 0.1393 s, while the 'ground truth' FE model increased from 4.541 s to 719.9 s. These results suggests that NNFE run times can be significantly reduced compared with the traditional large-deformation based finite element solution methods. The trade off is to train the NNFE off-line within a range of anticipated physiological responses. However, training time would only have to be performed once before any number of application uses. Moreover, since the NNFE is an analytical function its computational performance will be amplified when the corresponding problem becomes more complex.

13.
Chem Zvesti ; 76(9): 5655-5675, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35669698

RESUMEN

Distichochlamys citrea M.F. Newman (commonly known as "Black Ginger") is an endemic plant to Vietnam and has been extensively exploited by folk medication for treatments of infection-related diseases and diabetes. In this work, its rhizomes were subjected to fractionated extraction, phytochemical examination, evaluation of antioxidant effect by DDPH free radical neutralization, and inhibitory activity toward α-glucosidase. The compositional components were subjected to in silico screening, including density functional theory calculation, molecular docking simulation, physicochemical analysis, and pharmacokinetic regression. In the trials, EtOAc fraction is found as the bioactive part of most effectiveness, regarding both antioxidant effect (IC50 = 90.27 µg mL-1) and α-glucosidase inhibitory activity (IC50 = 115.75 µg mL-1). Chemical determination reveals there are 13 components of its composition. DFT-based calculations find no abnormal constraints in their structures. Docking-based simulation provides order of inhibitory effectiveness: 3-P53341 > 12-P53341 > 7-P53341 > 4-P53341 > 11-P53341 > 10-P53341. QSARIS-based investigations implicate their biocompatibility. ADMET-based regressions indicate that all candidates are generally safe for medicinal applications. The findings would contribute to the basis for further studies on the chemical compositions of Distichochlamys citrea and their biological activities. Supplementary Information: The online version contains supplementary material available at 10.1007/s11696-022-02273-2.

14.
Microb Pathog ; 156: 104902, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33930421

RESUMEN

Biological detergents are used in research laboratories, to extract or solubilize proteins from cell membranes. In order to evaluate the ability to extract antigens from the bacterial cell surface of the wild Vibrio cholerae strain C7258 and study their immunogenic potential by forming proteoliposomes and cochleate and preserving their immunogenicity, the non-ionic detergent, n-Octylglucoside (n-OG), and the Zwitterionic detergent (3-cholamidopropyl dimethylammonio 1-propanesulfonate; CHAPS) were tested in concentrations between 5 and 15%. The anionic detergent sodium deoxycholate (DOC) was used as a reference. Electrophoretic, immunochemical and electron microscopy techniques have characterized the extracts and their chromatographic fractions. With CHAPS and n-OG detergents in concentrations between 5 and 15%, a higher yield was obtained in the extraction of proteins and lipopolysaccharides (LPS) and other components from the bacterial surface compared to 10% DOC. When using 10% DOC, 15% CHAPS and n-OG between 5 and 15%, stable proteoliposomes were formed, of average size between 82 and 93 nm in diameter, with known proportions of proteins, LPS and other components. In some of the concentrations, liposomes were formed with almost pure proteins. Some cholera outer membrane proteins like the 17 kDa protein, which corresponds to the mannose-sensitive hemagglutinin (MSHA), which mediates the adhesion to the brush border of the small intestine and the outer membrane protein U (OMPU) were identified with monoclonal antibodies (mAbs) and purified. The fundamental components of liposomes, proteins and LPS, retained their molecular weights, when compared with known standards and by processing programs of electrophoretic profiles and their antigenicity, without alterations due to the extraction procedure, as could be verified by immune identification techniques with monoclonal antibodies in the case of LPS, significant antigens in this pathogen. The main purpose of the present work was to show that a new anticholera vaccine formulation based on cochleates, containing selected protein and LPS fraction extracted by detergents, is able to elicit protective high titers of bactericidal antibodies after intragastric immunization in the mice model. The objective was achieved.


Asunto(s)
Vacunas contra el Cólera , Cólera , Vibrio cholerae , Animales , Anticuerpos Antibacterianos , Antígenos Bacterianos , Inmunización , Ratones
15.
BMC Med Res Methodol ; 21(1): 142, 2021 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-34238247

RESUMEN

BACKGROUND: Standard practice for conducting systematic reviews (SRs) is time consuming and involves the study team screening hundreds or thousands of citations. As the volume of medical literature grows, the citation set sizes and corresponding screening efforts increase. While larger team size and alternate screening methods have the potential to reduce workload and decrease SR completion times, it is unknown whether investigators adapt team size or methods in response to citation set sizes. Using a cross-sectional design, we sought to understand how citation set size impacts (1) the total number of authors or individuals contributing to screening and (2) screening methods. METHODS: MEDLINE was searched in April 2019 for SRs on any health topic. A total of 1880 unique publications were identified and sorted into five citation set size categories (after deduplication): < 1,000, 1,001-2,500, 2,501-5,000, 5,001-10,000, and > 10,000. A random sample of 259 SRs were selected (~ 50 per category) for data extraction and analysis. RESULTS: With the exception of the pairwise t test comparing the under 1000 and over 10,000 categories (median 5 vs. 6, p = 0.049) no statistically significant relationship was evident between author number and citation set size. While visual inspection was suggestive, statistical testing did not consistently identify a relationship between citation set size and number of screeners (title-abstract, full text) or data extractors. However, logistic regression identified investigators were significantly more likely to deviate from gold-standard screening methods (i.e. independent duplicate screening) with larger citation sets. For every doubling of citation size, the odds of using gold-standard screening decreased by 15 and 20% at title-abstract and full text review, respectively. Finally, few SRs reported using crowdsourcing (n = 2) or computer-assisted screening (n = 1). CONCLUSIONS: Large citation set sizes present a challenge to SR teams, especially when faced with time-sensitive health policy questions. Our study suggests that with increasing citation set size, authors are less likely to adhere to gold-standard screening methods. It is possible that adjunct screening methods, such as crowdsourcing (large team) and computer-assisted technologies, may provide a viable solution for authors to complete their SRs in a timely manner.


Asunto(s)
Colaboración de las Masas , Estudios Transversales , Humanos , Tamizaje Masivo , Proyectos de Investigación , Revisiones Sistemáticas como Asunto
16.
Support Care Cancer ; 29(8): 4791-4798, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33537888

RESUMEN

PURPOSE: Cancer is a leading cause of death in Vietnam. To maximize quality of life (QOL) at the end of life, valid and clinically useful instruments are needed to assess palliative care needs and the effectiveness of palliative care interventions. METHODS: We aimed to (i) determine psychometric properties of the Vietnamese version of the WHO abbreviated quality of life scale (WHOQOL-BREFVN) among advanced cancer patients, (ii) measure HR-QOL, and (iii) identify predictors of HR-QOL. We collected demographic, clinical, and HR-QOL data from stage III/IV adult cancer patients at two major Vietnamese cancer centers. We determined the internal consistency (Cronbach's alpha), construct validity (confirmatory factor analysis (CFA)), and discriminant validity (known-groups comparison) of the Vietnamese instrument. HR-QOL was analyzed descriptively. Multinomial logistic regressions identified predictors of HR-QOL. RESULTS: A total of 825 patients participated. Missing data were completely at random (MCAR) (chi-square = 14.270, df = 14, p = 0.430). Cronbach's alpha for all items was 0.904. CFA loadings of physical, psychological, social relationship, and environment domains onto HR-QOL were 0.81, 0.82, 0.34, and 0.75, respectively. Prediction of scores differed significantly by functional status (Wilks' lambda = 0.784, chi-square = 197.546, df = 4, p < 0.01, correct prediction = 74.6%). HR-QOL was reported as very bad/bad by n = 188 patients (22.8%) and general health as very bad/bad by n = 430 (52.1%). Multinomial logistic regression (likelihood ratio test: chi-square = 35.494, df = 24, p = 0.061, correct prediction = 62.2%) and the Pearson correlations revealed worse HR-QOL was associated with inpatient status, high ECOG score, and having dependent children. CONCLUSION: The Vietnamese version of the WHOQOL-BREF has excellent internal consistency reliability and sound construct and discriminant validity in advanced cancer patients. Advanced cancer inpatients, those with dependent children, and those with poorer physical function appear to have the greatest palliative care needs.


Asunto(s)
Neoplasias/psicología , Calidad de Vida/psicología , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Autoinforme , Vietnam , Adulto Joven
17.
Environ Res ; 202: 111781, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34333011

RESUMEN

Solar-driven carbon dioxide (CO2) conversion has gained tremendous attention as a prominent strategy to simultaneously reduce the atmospheric CO2 concentration and convert solar energy into solar fuels in the form of chemical bonds. Numerous efforts have been devoted to diverse photo-driven processes for CO2 conversion, which utilized a multidisciplinary strategy. Among them, the architecture of nanostructured metal-based catalysts is emerging as an eminent solution for the design of catalysts of this field. In this work, we first provide fundamental mechanisms of photochemical, photoelectrochemical, photothermal, and photobio(electro)chemical CO2 reduction processes to achieve an in-deep understanding of vital aspects. Importantly, the recent progress in the catalyst design for each reaction system is discussed and highlighted. Based on these analyses, an overview of photo-driven CO2 reduction on metal-based catalysts for solar fuel production is also spotlighted. Finally, we analyze challenges and prospects for the strategic direction of developments in the field.


Asunto(s)
Dióxido de Carbono , Energía Solar , Catálisis , Metales , Luz Solar
18.
Molecules ; 26(12)2021 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-34204232

RESUMEN

Folk experiences suggest natural products in Tetradium ruticarpum can be effective inhibitors towards diabetes-related enzymes. The compounds were experimentally isolated, structurally elucidated, and tested in vitro for their inhibition effects on tyrosine phosphatase 1B (PTP1B) and α-glucosidase (3W37). Density functional theory and molecular docking techniques were utilized as computational methods to predict the stability of the ligands and simulate interaction between the studied inhibitory agents and the targeted proteins. Structural elucidation identifies two natural products: 2-heptyl-1-methylquinolin-4-one (1) and 3-[4-(4-methylhydroxy-2-butenyloxy)-phenyl]-2-propenol (2). In vitro study shows that the compounds (1 and 2) possess high potentiality for the inhibition of PTP1B (IC50 values of 24.3 ± 0.8, and 47.7 ± 1.1 µM) and α-glucosidase (IC50 values of 92.1 ± 0.8, and 167.4 ± 0.4 µM). DS values and the number of interactions obtained from docking simulation highly correlate with the experimental results yielded. Furthermore, in-depth analyses of the structure-activity relationship suggest significant contributions of amino acids Arg254 and Arg676 to the conformational distortion of PTP1B and 3W37 structures overall, thus leading to the deterioration of their enzymatic activity observed in assay-based experiments. This study encourages further investigations either to develop appropriate alternatives for diabetes treatment or to verify the role of amino acids Arg254 and Arg676.


Asunto(s)
Evodia/metabolismo , Inhibidores de Glicósido Hidrolasas/química , Proteína Tirosina Fosfatasa no Receptora Tipo 1/antagonistas & inhibidores , Productos Biológicos/química , Productos Biológicos/farmacología , Inhibidores Enzimáticos/farmacología , Simulación del Acoplamiento Molecular , Extractos Vegetales/química , Extractos Vegetales/farmacología , Proteína Tirosina Fosfatasa no Receptora Tipo 1/efectos de los fármacos , Proteína Tirosina Fosfatasa no Receptora Tipo 1/metabolismo , Relación Estructura-Actividad , alfa-Glucosidasas/efectos de los fármacos , alfa-Glucosidasas/metabolismo
19.
Nicotine Tob Res ; 22(9): 1640-1643, 2020 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-31811295

RESUMEN

INTRODUCTION: Given that people living with HIV (PLWH) are disproportionately burdened by tobacco-related morbidity and mortality, it is critically important to understand the degree to which evidence-based cessation interventions are utilized by and are effective among PLWH. AIMS AND METHODS: This secondary data analysis aimed to examine differences in Quitline treatment enrollment and 6-month cessation outcomes among smokers seeking care at 1 HIV clinic and 12 non-HIV clinics that were part of a large healthcare system in the greater Houston, Texas metropolitan area, United States. Data were from a 34-month (April 2013-February 2016) one-group implementation trial that evaluated the Ask-Advise-Connect (AAC) approach to linking smokers with Quitline treatment. Primary outcomes included (1) treatment enrollment and (2) 6-month self-reported and biochemically confirmed abstinence. RESULTS: The smoking status of 218 915 unique patients was recorded in the electronic health record; 5285 (2.7%) of these patients were seen at the HIV clinic where the smoking prevalence was 45.9%; smoking prevalence at the non-HIV clinics was 17.9%. The proportion of identified smokers who enrolled in treatment was 10.8% at the HIV clinic and 11.8% at the non-HIV clinics. The self-reported abstinence rate was 18.7% among HIV clinic patients and 16.5% among non-HIV clinic patients. Biochemically confirmed abstinence was lower at 4.2% and 4.5%, respectively (all ps > .05). CONCLUSIONS: AAC resulted in rates of Quitline treatment enrollment and abstinence rates that were comparable among patients seen at an HIV clinic and non-HIV clinics. Findings suggest that AAC should be considered for widespread implementation in HIV clinics. IMPLICATIONS: PLWH were as likely as other patients to enroll in evidence-based tobacco cessation treatment when it was offered in the context of a primary care visit. Cessation outcomes were also comparable. Therefore, standard care for PLWH should include routine screening for smoking status and referrals to cessation treatment.


Asunto(s)
Comunicación , Infecciones por VIH/terapia , Aceptación de la Atención de Salud/psicología , Fumadores/psicología , Cese del Hábito de Fumar/métodos , Teléfono/estadística & datos numéricos , Fumar Tabaco/terapia , Atención a la Salud , Infecciones por VIH/epidemiología , Infecciones por VIH/psicología , Conductas Relacionadas con la Salud , Humanos , Derivación y Consulta , Cese del Hábito de Fumar/psicología , Telemedicina , Texas/epidemiología , Fumar Tabaco/epidemiología , Fumar Tabaco/psicología
20.
Trop Anim Health Prod ; 52(6): 3781-3788, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33011908

RESUMEN

Porcine epidemic diarrhea (PED) virus (PEDV) is a globally emerging and re-emerging epizootic swine virus that causes massive economic losses in the swine industry, with high mortality in piglets. In Vietnam, PED first emerged in 2009 and has now developed to an endemic stage. This is the first cross-sectional survey performed to evaluate the proportion of PEDV-positive swine farms in Vietnam from January 2018 to February 2019. Fecal samples from 327 pig farms in northern Vietnam were collected and tested for PEDV infection by reverse transcription-loop-mediated isothermal amplification (RT-LAMP) method. The proportion of PEDV-positive farms was 30.9% and PEDV-positive farms were distributed throughout the study area. The highest proportion of PEDV-positive farms was 70% (7/10) among nucleus production type farms (P < 0.05). Higher proportions of PEDV-positive farms were found in the Northeast and Red River Delta areas, which are the major areas of pig production (P < 0.05). The proportion of PEDV-positive farms was higher among larger farms (P < 0.05). Our findings illustrate the high proportion of PEDV-positive farms in the Vietnamese pig population and will help to better understand the epidemiological dynamics of PED infection, to estimate impact, and establish and improve prevention and control measures.


Asunto(s)
Virus de la Diarrea Epidémica Porcina/aislamiento & purificación , Enfermedades de los Porcinos/virología , Animales , Infecciones por Coronavirus/veterinaria , Estudios Transversales , Diarrea/veterinaria , Epidemias , Heces/virología , Técnicas de Diagnóstico Molecular , Técnicas de Amplificación de Ácido Nucleico , Virus de la Diarrea Epidémica Porcina/genética , Porcinos , Enfermedades de los Porcinos/epidemiología , Vietnam/epidemiología
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