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1.
Lancet Infect Dis ; 24(2): 150-160, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37776876

RESUMO

BACKGROUND: Morbidity and mortality from dengue virus (DENV) is rapidly growing in the large populations of south Asia. Few formal evaluations of candidate dengue vaccine candidates have been undertaken in India, Pakistan, or Bangladesh. Tetravalent vaccines must be tested for safety and immunogenicity in all age groups and in those previously exposed and naive to DENV infections. TV005 is a live, attenuated tetravalent dengue vaccine. We evaluated the safety and immunogenicity of a single dose of TV005 across age groups in dengue-endemic Bangladesh. METHODS: We performed a randomised, placebo-controlled age de-escalating clinical trial of TV005 at a single clinical site in dengue-endemic Dhaka, Bangladesh, following a technology transfer from the USA. Healthy (as determined by history, clinical examination, and safety laboratory test results) volunteers aged 1-50 years were randomly assigned 3:1 (stratified by four age groups) to receive a single dose of TV005 vaccine or placebo. Participants were followed up for 3 years. The study was double blind and was unmasked at day 180; outcome assessors, clinic staff, and volunteers remained blind throughout. Primary outcomes were safety, evaluated per-protocol as proportion of volunteers with solicited related adverse events of any severity through 28 days post dosing, and post-vaccination seropositivity by day 180 using serotype-specific neutralising antibodies (PRNT50 ≥10). Secondary outcomes included viremia, impact of past dengue exposure, and durability of antibody responses. This study is registered with Clinicaltrials.gov, NCT02678455, and is complete. FINDINGS: Between March 13, 2016, and Feb 14, 2017, 192 volunteers were enrolled into four age groups (adults [18-50 years; 20 male and 28 female], adolescents [11-17 years; 27 male and 21 female], children [5-10 years; 15 male and 33 female], and young children [1-4 years; 29 male and 19 female]) with 48 participant per group. All participants were Bangladeshi. Vaccination was well tolerated and most adverse events were mild. Rash was the most common vaccine-associated solicited adverse event, in 37 (26%) of 144 vaccine recipients versus six (12%) of 48 placebo recipients; followed by fever in seven (5% of 144) and arthralgias in seven (6% of 108), which were only observed in vaccine recipients. Post-vaccine, volunteers of all ages (n=142) were seropositive to most serotypes with 118 (83%) seropositive to DENV 1, 141 (99%) to DENV 2, 137 (96%) to DENV 3, and 124 (87%) to DENV 4, overall by day 180. Post-vaccination, viraemia was not consistently found and antibody titres were higher (10-15-fold for DENV 1-3 and 1·6-fold for DENV 4) in individuals with past dengue exposure compared with the dengue-naive participants (DENV 1 mean 480 [SD 4·0] vs 32 [2·4], DENV 2 1042 [3·2] vs 105 [3·1], DENV 3 1406 [2·8] vs 129 [4·7], and DENV 4 105 [3·3] vs 65 [3·1], respectively). Antibody titres to all serotypes remained stable in most adults (63-86%) after 3 years of follow-up. However, as expected for individuals without past exposure to dengue, titres for DENV 1, 3, and 4 waned by 3 years in the youngest (1-4 year old) cohort (69% seropositive for DENV 2 and 22-28% seropositive for DENV 1, 3, and 4). INTERPRETATION: With 3 years of follow-up, the single-dose tetravalent dengue vaccine, TV005, was well tolerated and immunogenic for all four serotypes in young children to adults, including individuals with no previous dengue exposure. FUNDING: National Institutes of Health-National Institute of Allergy and Infectious Diseases Intramural Research Program and Johns Hopkins University. TRANSLATION: For the Bangla translation of the abstract see Supplementary Materials section.


Assuntos
Vacinas contra Dengue , Vírus da Dengue , Dengue , Adulto , Criança , Adolescente , Humanos , Masculino , Feminino , Pré-Escolar , Lactente , Sorogrupo , Bangladesh , Vacinas Atenuadas , Método Duplo-Cego , Viremia , Imunogenicidade da Vacina , Anticorpos Antivirais
2.
Chemosphere ; 344: 140287, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37820879

RESUMO

In this research, graphitic carbon nitride/zinc oxide-copper denoted as GCN/ZnO-Cu nanocomposite photocatalysts were synthesized using a novel facile synthesis process, the co-exfoliation method involving ultrasonic exfoliation of the mixture of GCN and ZnO-Cu in ethanol and then thermal exfoliation. Different characterization techniques such as X-ray diffraction (XRD), mean crystallite size (MCS), BET surface area, transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), particle size distribution (PSD), Fourier transform-infrared spectroscopy (FT-IR), photoluminescence (PL) spectra, and ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS) were conducted to study the crystallinity, morphology, elemental composition, chemical structure, and optoelectronic properties. The band gap was estimated using the UV-Vis DRS results and Tauc plots. The photocatalytic activity of the GCN/ZnO-Cu3% nanocomposites was evaluated in the degradation of 4-chlorophenol (4-CP), and the disinfection of wastewater primary influent under a narrowband visible light source, royal blue LED (λ = 450 nm). GCN/0.1ZnO-Cu3% nanocomposite showed the best performance in the degradation of 4-CP and the disinfection of municipal wastewater primary influent. For 4-CP degradation, GCN/0.1ZnO-Cu3% was 2.2 times better than GCN, 9.4 times better than ZnO-Cu3%, and 1.8 times better than the sum of the individual GCN and ZnO-Cu3%. A 5.5 log reduction was achieved for the disinfection of total coliforms in wastewater primary influent in 360 min. This enhanced photocatalytic activity of GCN/ZnO-Cu3% nanocomposite can be attributed to the synergistic of GCN and the ZnO-Cu3%, resulting in a large surface area and improved bandgap.


Assuntos
Nanocompostos , Óxido de Zinco , Óxido de Zinco/química , Águas Residuárias , Cobre/química , Espectroscopia de Infravermelho com Transformada de Fourier , Desinfecção , Luz , Nanocompostos/química , Catálise
3.
bioRxiv ; 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37090580

RESUMO

Metastasis is the cause of over 90% of all deaths associated with breast cancer, yet the strategies to predict cancer spreading based on primary tumor profiles and therefore prevent metastasis are egregiously limited. As rare precursor cells to metastasis, circulating tumor cells (CTCs) in multicellular clusters in the blood are 20-50 times more likely to produce viable metastasis than single CTCs. However, the molecular mechanisms underlying various CTC clusters, such as homotypic tumor cell clusters and heterotypic tumor-immune cell clusters, are yet to be fully elucidated. Combining machine learning-assisted computational ranking with experimental demonstration to assess cell adhesion candidates, we identified a transmembrane protein Plexin- B2 (PB2) as a new therapeutic target that drives the formation of both homotypic and heterotypic CTC clusters. High PB2 expression in human primary tumors predicts an unfavorable distant metastasis-free survival and is enriched in CTC clusters compared to single CTCs in advanced breast cancers. Loss of PB2 reduces formation of homotypic tumor cell clusters as well as heterotypic tumor-myeloid cell clusters in triple-negative breast cancer. Interactions between PB2 and its ligand Sema4C on tumor cells promote homotypic cluster formation, and PB2 binding with Sema4A on myeloid cells (monocytes) drives heterotypic CTC cluster formation, suggesting that metastasizing tumor cells hijack the PB2/Sema family axis to promote lung metastasis in breast cancer. Additionally, using a global proteomic analysis, we identified novel downstream effectors of the PB2 pathway associated with cancer stemness, cell cycling, and tumor cell clustering in breast cancer. Thus, PB2 is a novel therapeutic target for preventing new metastasis.

4.
J Stat Theory Appl ; 21(4): 217-241, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36268516

RESUMO

The distribution of the ratio of two independently distributed Lindley random variables X and Y , with different parameters, is derived. The associated distributional properties are provided. Furthermore, the proposed ratio distribution is fitted to two applications data (COVID-19 and Bladder Cancer Data), and compared it with some well-known right-skewed variations of Lindley distribution, namely; Lindley distribution, new generalized Lindley distribution, new quasi Lindley distribution and a three parameter Lindley distribution. The numerical result of the study reveals that the proposed distribution of two independent Lindley random variables fits better to the above said data sets than the compared distribution.

5.
Eur J Pharm Biopharm ; 165: 13-21, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33971271

RESUMO

We previously demonstrated that amorphous aggregates of misfolded VHH-7D12 antibodies (VHH-Mis), a potential anti-EGFR drug, can generate a robust serum IgG response. Here we investigate the immunogenic nature, especially the specificity of the immune response induced by VHH-Mis. To this end, we used two natively folded and 77% identical anti-EGFR VHHs (VHH-7D12 and VHH-9G8) that possess a common framework but distinct complementarity determining regions (CDRs). In 60% of mice immunized with VHH-Mis, the anti-VHH-7D12 IgG titer was stronger than the anti-VHH-9G8 titer (Group-1). In the remaining mice (40%; Group-2), the anti-VHH-7D12 and anti-VHH-9G8 titer were almost identical. We rationalized these results by hypothesizing that mice in Group-1 produced IgG mostly against the VHH-7D12's CDRs, whereas in Group-2 mice, they targeted the VHH's framework. The IgG specificity against VHH-7D12 and VHH-9G8 was essentially unchanged over 17 weeks in both groups. Further, in all mice (Group-1&2) re-immunized with native VHH-7D12, the IgG titer against VHH-7D12 increased sharply but not against VHH-9G8. On the other hand, none of the three Group-1 mice re-immunized with native VHH-9G8 showed immunogenicity against VHH-7D12 nor VHH-9G8. Whereas, in Group-2 mice (three/three) re-immunized with VHH-9G8, the IgG titers against both VHHs increased but slowly. Flow-cytometric studies showed that VHH-Mis immunized mice generated a higher number of effector and central memory T-cells. Overall, these observations indicate that amorphous aggregates made of a misfolded VHH can induce serum IgG against its natively folded self and analogous VHHs having a similar framework but distinct CDRs. Furthermore, a robust long-term immune response with memory was established against its natively folded self but with a nil-to-moderate immune response against natively folded VHH analogs.


Assuntos
Anticorpos Monoclonais/imunologia , Regiões Determinantes de Complementaridade/imunologia , Receptores ErbB/antagonistas & inibidores , Memória Imunológica , Agregados Proteicos/imunologia , Animais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/química , Anticorpos Monoclonais/metabolismo , Regiões Determinantes de Complementaridade/administração & dosagem , Regiões Determinantes de Complementaridade/química , Regiões Determinantes de Complementaridade/metabolismo , Difusão Dinâmica da Luz , Feminino , Camundongos , Modelos Animais , Dobramento de Proteína , Fatores de Tempo
6.
J Appl Stat ; 48(9): 1559-1578, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35706568

RESUMO

In the logistic regression model, the variance of the maximum likelihood estimator is inflated and unstable when the multicollinearity exists in the data. There are several methods available in literature to overcome this problem. We propose a new stochastic restricted biased estimator. We study the statistical properties of the proposed estimator and compare its performance with some existing estimators in the sense of scalar mean squared criterion. An example and a simulation study are provided to illustrate the performance of the proposed estimator.

7.
Iran J Sci Technol Trans A Sci ; 44(6): 1775-1789, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33041601

RESUMO

Månsson and Shukur (Econ Model 28:1475-1481, 2011) proposed a Poisson ridge regression estimator (PRRE) to reduce the negative effects of multicollinearity. However, a weakness of the PRRE is its relatively large bias. Therefore, as a remedy, Türkan and Özel (J Appl Stat 43:1892-1905, 2016) examined the performance of almost unbiased ridge estimators for the Poisson regression model. These estimators will not only reduce the consequences of multicollinearity but also decrease the bias of PRRE and thus perform more efficiently. The aim of this paper is twofold. Firstly, to derive the mean square error properties of the Modified Almost Unbiased PRRE (MAUPRRE) and Almost Unbiased PRRE (AUPRRE) and then propose new ridge estimators for MAUPRRE and AUPRRE. Secondly, to compare the performance of the MAUPRRE with the AUPRRE, PRRE and maximum likelihood estimator. Using both simulation study and real-world dataset from the Swedish football league, it is evidenced that one of the proposed, MAUPRRE ( k ^ q 4 ) performed better than the rest in the presence of high to strong (0.80-0.99) multicollinearity situation.

8.
ScientificWorldJournal ; 2020: 3192852, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32508537

RESUMO

The general linear regression model has been one of the most frequently used models over the years, with the ordinary least squares estimator (OLS) used to estimate its parameter. The problems of the OLS estimator for linear regression analysis include that of multicollinearity and outliers, which lead to unfavourable results. This study proposed a two-parameter ridge-type modified M-estimator (RTMME) based on the M-estimator to deal with the combined problem resulting from multicollinearity and outliers. Through theoretical proofs, Monte Carlo simulation, and a numerical example, the proposed estimator outperforms the modified ridge-type estimator and some other considered existing estimators.

9.
NPJ Clean Water ; 3: 20, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-33777415

RESUMO

This study explores the associations of drinking rainwater with mineral intake and cardiometabolic health in the Bangladeshi population. We pooled 10030 person-visit data on drinking water sources, blood pressure (BP) and 24-h urine minerals. Fasting blood glucose (FBG) was measured in 3724 person-visits, and lipids in 1118 person-visits. We measured concentrations of sodium (Na), potassium (K), calcium (Ca) and magnesium (Mg) in 253 rainwater, 935 groundwater and 130 pond water samples. We used multilevel linear or gamma regression models with participant-, household- and community-level random intercepts to estimate the associations of rainwater consumption with urine minerals and cardiometabolic biomarkers. Rainwater samples had the lowest concentrations of Na, K, Ca and Mg. Rainwater drinkers had lower urine minerals than coastal groundwater drinkers: -13.42 (95% CI: -18.27, -8.57) mmol Na/24 h, -2.00 (95% CI: -3.16, -0.85) mmol K/24 h and -0.57 (95% CI: -1.02, -0.16) mmol Mg/24 h. The ratio of median 24-hour urinary Ca for rainwater versus coastal groundwater drinkers was 0.72 (95% CI: 0.64, 0.80). Rainwater drinkers had 2.15 (95% CI: 1.02, 3.27) mm Hg higher systolic BP, 1.82 (95% CI: 1.19, 2.54) mm Hg higher diastolic BP, 0.59 (95% CI: 0.17, 1.01) mmol/L higher FBG and -2.02 (95% CI: -5.85, 0.81) mg/dl change in high-density lipoprotein cholesterol compared with the coastal groundwater drinkers. Drinking rainwater was associated with worse cardiometabolic health measures, which may be due to the lower intake of salubrious Ca, Mg and K.

10.
J Am Heart Assoc ; 8(9): e012007, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-31060415

RESUMO

Background Sodium (Na+) in saline water may increase blood pressure ( BP ), but potassium (K+), calcium (Ca2+), and magnesium (Mg2+) may lower BP . We assessed the association between drinking water salinity and population BP . Methods and Results We pooled 6487 BP measurements from 2 cohorts in coastal Bangladesh. We used multilevel linear models to estimate BP differences across water salinity categories: fresh water (electrical conductivity, <0.7 mS/cm), mild salinity (electrical conductivity ≥0.7 and <2 mS/cm), and moderate salinity (electrical conductivity ≥2 and <10 mS/cm). We assessed whether salinity categories were associated with hypertension using multilevel multinomial logistic models. Models included participant-, household-, and community-level random intercepts. Models were adjusted for age, sex, body mass index ( BMI ), physical activity, smoking, household wealth, alcohol consumption, sleep hours, religion, and salt consumption. We evaluated the 24-hour urinary minerals across salinity categories, and the associations between urinary minerals and BP using multilevel linear models. Compared with fresh water drinkers, mild-salinity water drinkers had lower mean systolic BP (-1.55 [95% CI : -3.22-0.12] mm Hg) and lower mean diastolic BP (-1.26 [95% CI : -2.21--0.32] mm Hg) adjusted models. The adjusted odds ratio among mild-salinity water drinkers for stage 1 hypertension was 0.60 (95% CI : 0.43-0.84) and for stage 2 hypertension was 0.56 (95% CI : 0.46-0.89). Mild-salinity water drinkers had high urinary Ca2+, and Mg2+, and both urinary Ca2+ and Mg2+ were associated with lower BP. Conclusions Drinking mild-salinity water was associated with lower BP , which can be explained by higher intake of Ca2+ and Mg2+ through saline water.


Assuntos
Pressão Sanguínea , Cálcio/urina , Água Potável/análise , Hipertensão/fisiopatologia , Magnésio/urina , Eliminação Renal , Salinidade , Sódio/urina , Adulto , Idoso , Bangladesh/epidemiologia , Condutividade Elétrica , Feminino , Humanos , Hipertensão/epidemiologia , Hipertensão/prevenção & controle , Hipertensão/urina , Masculino , Pessoa de Meia-Idade , Fatores de Proteção , Fatores de Risco , Adulto Jovem
11.
Sensors (Basel) ; 19(3)2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30682810

RESUMO

Multipath TCP (MPTCP), which enables the use of multiple wireless links (e.g., Wi-Fi and LTE) for data transmissions, is an excellent technology for evolving multi-homing devices in mobile wireless networks. This paper explores concepts and feasibility of realizing MPTCP with path awareness (PA), in which the path-aware information is leveraged to reinforce the MPTCP transmissions. In particular, when aware of a network situation, a device can facilitate a mechanism that dynamically shifts the MPTCP traffic to a single path and vice versa. As a result, MPTCP with PA could solve the significant problem of negative aggregation benefit when the MPTCP throughput over divergent paths is worse than the best one of single-path TCP. We illustrate the feasibility of the proposed concept through our new implementation of a so-called MPTCP-LA (i.e., MPTCP with Loss Awareness). MPTCP-LA keeps the aggregation benefits non-negative by temporarily switching an MPTCP transmission on a path to a standby condition when the on-device observed loss reaches a threshold. We extensively evaluate MPTCP-LA in comparison to the standard MPTCP in an emulated environment. The results show that MPTCP-LA has better performance regarding enhancing throughput and saving networking resources.

12.
Environ Sci Technol ; 53(4): 2105-2113, 2019 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-30653305

RESUMO

We evaluated the effectiveness of a sand barrier around latrine pits in reducing fecal indicator bacteria (FIB) leaching into shallow groundwater. We constructed 68 new offset single pit pour flush latrines in the Galachipa subdistrict of coastal Bangladesh. We randomly assigned 34 latrines to include a 50 cm thick sand barrier under and around the pit and 34 received no sand barrier. Four monitoring wells were constructed around each pit to collect water samples at baseline and subsequent nine follow-up visits over 24 months. Samples were tested using the IDEXX Colilert method to enumerate E. coli and thermotolerant coliforms most probable number (MPN). We determined the difference in mean log10MPN FIB counts/100 mL in monitoring well samples between latrines with and without a sand barrier using multilevel linear models and reported cluster robust standard error. The sand barrier latrine monitoring well samples had 0.38 mean log10MPN fewer E. coli (95% CI: 0.16, 0.59; p = 0.001) and 0.38 mean log10MPN fewer thermotolerant coliforms (95% CI: 0.14, 0.62; p = 0.002), compared to latrines without sand barriers, a reduction of 27% E. coli and 24% thermotolerant coliforms mean counts. A sand barrier can modestly reduce the risk presented by pit leaching.


Assuntos
Escherichia coli , Água Subterrânea , Banheiros , Bactérias , Bangladesh , Sedimentos Geológicos , Distribuição Aleatória
13.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-84974

RESUMO

BACKGROUND/AIMS: Functional gastrointestinal disorders (FGIDs), diagnosed by symptom-based criteria due to lack of biomarkers, need translated-validated questionnaires in different languages. As Bengali, the mother tongue of Bangladesh and eastern India, is the seventh most spoken language in the world, we translated and validated the Enhanced Asian Rome III questionnaire (EAR3Q) in this language. METHODS: The EAR3Q was translated in Bengali as per guideline from the Rome Foundation. The translated questionnaire was validated prospectively on Bengali-speaking healthy subjects (HS, n = 30), and patients with functional dyspepsia (FD, n = 35), irritable bowel syndrome (IBS, n = 40) and functional constipation (FC, n = 12) diagnosed by clinicians using the Rome III criteria. The subjects were asked to fill-in the questionnaire again after 2 weeks, to check for its reproducibility. RESULTS: During translation, the original and the backward translated English versions of the questionnaire demonstrated high concordance. Sensitivity of the Bengali questionnaire to diagnose patients with FD, IBS, FC, and HS was 100%, 100%, 75%, and 100%, respectively, considering diagnosis by the clinicians as the gold standard. On test-retest reliability analysis, Kappa values for FD, IBS, FC, and HS were 1.0, 1.0, 0.83, and 1.0, respectively. The Bengali questionnaire detected considerable overlap of FD symptoms among patients with IBS, IBS among patients with FD, and FD among patients with FC, which were not detected by the clinicians. CONCLUSIONS: We successfully translated and validated the EAR3Q in Bengali. We believe that this translated questionnaire will be useful for clinical evaluation and research on FGIDs in the Bengali-speaking population.


Assuntos
Humanos , Povo Asiático , Bangladesh , Biomarcadores , Constipação Intestinal , Diagnóstico , Dispepsia , Gastroenteropatias , Índia , Síndrome do Intestino Irritável , Mães , Estudos Prospectivos , Língua
14.
Nanotechnology ; 23(8): 085205, 2012 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-22293649

RESUMO

We report on the achievement of, for the first time, InN/InGaN core/shell nanowire heterostructures, which are grown directly on Si(111) substrates by plasma-assisted molecular beam epitaxy. The crystalline quality of the heterostructures is confirmed by transmission electron microscopy, and the elemental mapping through energy dispersive x-ray spectrometry further reveals the presence of an InGaN shell covering the sidewall and top regions of the InN core. The optical characterizations reveal two emission peaks centered at ∼1685 nm and 1845 nm at 5 K, which are related to the emission from the InGaN shell and InN core, respectively. The InN/InGaN core/shell nanoscale heterostructures exhibit a very high internal quantum efficiency of ∼62% at room temperature, which is attributed to the strong carrier confinement provided by the InGaN shell as well as the nearly intrinsic InN core.


Assuntos
Cristalização/métodos , Gálio/química , Índio/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Pontos Quânticos , Silício/química , Catálise , Gálio/efeitos da radiação , Íons Pesados , Índio/efeitos da radiação , Substâncias Macromoleculares/química , Substâncias Macromoleculares/efeitos da radiação , Teste de Materiais , Conformação Molecular/efeitos da radiação , Nanoestruturas/efeitos da radiação , Tamanho da Partícula , Porosidade , Propriedades de Superfície/efeitos da radiação
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