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1.
Viruses ; 16(5)2024 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-38793578

RESUMO

The Vietnam Ministry of Health (MOH) has intensified efforts in its aim to eliminate AIDS by 2030. Expanding the program for prevention of mother-to-child transmission (PMTCT) is a significant step towards achieving this goal. However, there are still HIV-exposed children who do not have access to PMTCT services, and some who have participated in the program but still contracted HIV. This study focused on assessing the prevalence and profile of HIV mutations among children under 18 months of age who had recently tested positive for HIV, while gaining insights into the implementation of early infant diagnostic (EID) tests. Between 2017 and 2021, 3.43% of 5854 collected dry blood spot (DBS) specimens from Vietnam's Central and Southern regions showed positive EID results. This study identified a high prevalence of resistance mutations in children, totaling 62.9% (95% CI: 53.5-72.3). The highest prevalence of mutations was observed for NNRTIs, with 57.1% (95% CI: 47.5-66.8). Common mutations included Y181C and K103N (NNRTI resistance), M184I/V (NRTI resistance), and no major mutations for PI. The percentage of children with any resistance mutation was significantly higher among those who received PMTCT interventions (69.2%; 95% CI: 50.5-92.6%) compared with those without PMTCT (45.0%; 95% CI: 26.7-71.1%) with χ2 = 6.06, p = 0.0138, and OR = 2.75 (95% CI: 1.13-6.74). Mutation profiles revealed that polymorphic mutations could be present regardless of whether PMTCT interventions were implemented or not. However, non-polymorphic drug resistance mutations were predominantly observed in children who received PMTCT measures. Regarding PMTCT program characteristics, this study highlights the issue of late access to HIV testing for both mothers and their infected children. Statistical differences were observed between PMTCT and non-PMTCT children. The proportion of late detection of HIV infection and breastfeeding rates were significantly higher among non-PMTCT children (p < 0.05). Comparative analysis between children with low viral load (≤200 copies/mL) and high viral load (>200 copies/mL) showed significant differences between the mothers' current ART regimens (p = 0.029) and the ARV prophylaxis regimen for children (p = 0.016). These findings emphasize the need for comprehensive surveillance to assess the effectiveness of the PMTCT program, including potential transmission of HIV drug-resistance mutations from mothers to children in Vietnam.


Assuntos
Farmacorresistência Viral , Infecções por HIV , HIV-1 , Transmissão Vertical de Doenças Infecciosas , Mutação , Humanos , Infecções por HIV/transmissão , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Infecções por HIV/prevenção & controle , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Vietnã/epidemiologia , Farmacorresistência Viral/genética , HIV-1/genética , HIV-1/efeitos dos fármacos , Feminino , Lactente , Masculino , Fármacos Anti-HIV/uso terapêutico , Prevalência , Recém-Nascido , Gravidez
2.
Front Chem ; 12: 1382319, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38690013

RESUMO

Introduction: 3D pharmacophore models describe the ligand's chemical interactions in their bioactive conformation. They offer a simple but sophisticated approach to decipher the chemically encoded ligand information, making them a valuable tool in drug design. Methods: Our research summarized the key studies for applying 3D pharmacophore models in virtual screening for 6,944 compounds of APJ receptor agonists. Recent advances in clustering algorithms and ensemble methods have enabled classical pharmacophore modeling to evolve into more flexible and knowledge-driven techniques. Butina clustering categorizes molecules based on their structural similarity (indicated by the Tanimoto coefficient) to create a structurally diverse training dataset. The learning method combines various individual pharmacophore models into a set of pharmacophore models for pharmacophore space optimization in virtual screening. Results: This approach was evaluated on Apelin datasets and afforded good screening performance, as proven by Receiver Operating Characteristic (AUC score of 0.994 ± 0.007), enrichment factor of (EF1% of 50.07 ± 0.211), Güner-Henry score of 0.956 ± 0.015, and F-measure of 0.911 ± 0.031. Discussion: Although one of the high-scoring models achieved statistically superior results in each dataset (AUC of 0.82; an EF1% of 19.466; GH of 0.131 and F1-score of 0.071), the ensemble learning method including voting and stacking method balanced the shortcomings of each model and passed with close performance measures.

3.
Nat Prod Bioprospect ; 14(1): 4, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38185713

RESUMO

Diabetes mellitus remains a major global health issue, and great attention is directed at natural therapeutics. This systematic review aimed to assess the potential of flavonoids as antidiabetic agents by investigating their inhibitory effects on α-glucosidase and α-amylase, two key enzymes involved in starch digestion. Six scientific databases (PubMed, Virtual Health Library, EMBASE, SCOPUS, Web of Science, and WHO Global Index Medicus) were searched until August 21, 2022, for in vitro studies reporting IC50 values of purified flavonoids on α-amylase and α-glucosidase, along with corresponding data for acarbose as a positive control. A total of 339 eligible articles were analyzed, resulting in the retrieval of 1643 flavonoid structures. These structures were rigorously standardized and curated, yielding 974 unique compounds, among which 177 flavonoids exhibited inhibition of both α-glucosidase and α-amylase are presented. Quality assessment utilizing a modified CONSORT checklist and structure-activity relationship (SAR) analysis were performed, revealing crucial features for the simultaneous inhibition of flavonoids against both enzymes. Moreover, the review also addressed several limitations in the current research landscape and proposed potential solutions. The curated datasets are available online at https://github.com/MedChemUMP/FDIGA .

4.
Int Breastfeed J ; 18(1): 47, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37653448

RESUMO

BACKGROUND: Although breastfeeding is practiced by 98% of mothers in Vietnam, infant breastfeeding behaviors remain far from World Health Organization recommendations and continues to decline. This study aims to explore the prevalence and factors associated with exclusive breastfeeding in the first six months of an infant's life. METHODS: A cross-sectional study utilized a self-administered maternal questionnaire to collect data on 1072 Vietnamese mothers who brought infants aged between 6 and 30 months to a community health centre (CHC) for routine vaccination. Data collection was conducted from March to May 2021 in two cities in Central and North Vietnam. In order to measure exclusive breastfeeding, we asked mothers to recall (yes / no), if the child had received breast milk, formula, colostrum milk powder, water, vitamin / medicine, fruit juice / honey, and complementary foods aged under six months. RESULTS: In the first six months, 14.2% of mothers exclusively breastfed their infants. Multivariable logistic regression analysis demonstrated a significant association between exclusive infant breastfeeding and the highest maternal education level (university or postgraduate) (adjusted odds ratio (aOR) 2.55; 95% confidence interval (CI) 1.10, 5.91); male infants (aOR 1.72; 95% CI 1.11, 2.68); duration of skin-to-skin contact greater than 90 min (aOR 7.69; 95% CI 1.95, 30.38); receiving first breastfeeding during skin-to-skin contact (aOR 2.31; 95% CI 1.30, 4.10); completely feeding infant directly at the breast (aOR 1.65; 95% CI 1.00, 2.71) and exclusive breastfeeding intention during pregnancy (aOR 2.48; 95% CI 1.53, 4.00). When compared with mothers who were prenatally exposed to infant formula advertising classified as "often", the prevalence of exclusive infant breastfeeding was higher in mothers who classified their prenatal exposure to infant formula advertising as "sometimes" (aOR 2.15; 95% CI 1.13, 4.10), and "seldom" (aOR 2.58; 95% CI 1.25, 5.36). CONCLUSION: The prevalence of mothers who practiced exclusive infant breastfeeding during the first six months in Vietnam was low. Infants should receive early maternal-infant skin-to-skin contact greater than 90 min and complete first breastfeeding during skin-to-skin contact. Further, mothers should be protected against infant formula advertisements to maximise the likelihood of exclusive breastfeeding during the child's infancy.


Assuntos
Aleitamento Materno , Países em Desenvolvimento , Feminino , Criança , Gravidez , Humanos , Lactente , Masculino , Pré-Escolar , Prevalência , Estudos Transversais , Leite Humano
5.
J Clin Imaging Sci ; 13: 19, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37559877

RESUMO

Objectives: This study aimed to assess the value of magnetic resonance perfusion (MR perfusion) and magnetic resonance spectroscopy (MR spectroscopy) in 3.0-Tesla magnetic resonanceimaging (MRI) for differential diagnosis of glioblastoma (GBM) and solitary brain metastasis (SBM). Material and Methods: This retrospective study involved 36 patients, including 24 cases of GBM and 12 of SBM diagnosed using histopathology. All patients underwent a 3.0-Tesla MRI examination with pre-operative MR perfusion and MR spectroscopy. We assessed the differences in age, sex, cerebral blood volume (CBV), relative CBV (rCBV), and the metabolite ratios of choline/N-acetylaspartate (Cho/NAA) and Cho/creatine between the GBM and SBM groups using the Mann-Whitney U-test and Chi-square test. The cutoff value, area under the curve, sensitivity, specificity, positive predictive value, and negative predictive value of the significantly different parameters between these two groups were determined using the receiver operating characteristic curve. Results: In MR perfusion, the CBV of the peritumoral region (pCBV) had the highest preoperative predictive value in discriminating GBM from SBM (cutoff: 1.41; sensitivity: 70.83%; and specificity: 83.33%), followed by the ratio of CBV of the solid tumor component to CBV of normal white matter (rCBVt/n) and the ratio of CBV of the pCBV to CBV of normal white matter (rCBVp/n). In MR spectroscopy, the Cho/NAA ratio of the pCBV (pCho/NAA; cutoff: 1.02; sensitivity: 87.50%; and specificity: 75%) and the Cho/NAA ratio of the solid tumor component (tCho/NAA; cutoff: 2.11; sensitivity: 87.50%; and specificity: 66.67%) were significantly different between groups. Moreover, combining these remarkably different parameters increased their diagnostic utility for distinguishing between GBM and SBM. Conclusion: pCBV, rCBVt/n, rCBVp/n, pCho/NAA, and tCho/NAA are useful indices for differentiating between GBM and SBM. Combining these indices can improve diagnostic performance in distinguishing between these two tumors.

6.
Ther Clin Risk Manag ; 19: 269-278, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36941979

RESUMO

Objective: This study aimed to assess the predictive value of preoperative diffusion tensor imaging (DTI) data for surgical outcomes of patients with supratentorial glioma in the motor function area. Patients and Methods: This is a retrospective study of 43 patients receiving navigation-guided surgery for histopathologically demonstrated supratentorial glioma in the motor function area. All patients underwent preoperative 3 Tesla magnetic resonance imaging examinations with conventional and DTI sequences. Data on preoperative imaging and pre- and postoperative clinical characteristics of patients were retrospectively collected. Univariate and multivariate linear regressions were applied to analyze the relationships between preoperative parameters and pre- and postoperative muscle strength and the Karnofsky Performance Status (KPS) score. Results: Fourteen patients had low-grade gliomas and 29 had high-grade gliomas. Although the corticospinal tract (CST) score did not differ significantly between tumor grades, edema and deviation were common in low-grade gliomas (64.3%), while destroyed and infiltrated lesions were common in high-grade gliomas (58.6%). Muscle strength improved after surgery in the deviated tract group (40%) more than in the infiltrated tract group (33.3%). Two independent indices, preoperative muscle strength (p = 0.000) and glioma-to-CST distance (p = 0.001), were linearly related to postoperative muscle strength. The preoperative KPS score was the only indicator that affected the postoperative KPS score (p = 0.000). Conclusion: DTI should be considered in surgical management of supratentorial gliomas in the motor function area to determine the appropriate surgical strategy and predict the nature of the tumor and postoperative motor function.

7.
Int J Mol Sci ; 23(19)2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36232636

RESUMO

Estrogen receptors are indicators of breast cancer adaptability to endocrine therapies, such as tamoxifen. Deficiency or absence of estrogen receptor α (ER-α) in breast cancer cells results in reduced efficacy of endocrine therapy. Here, we investigated the effect of combined tamoxifen and pentadecanoic acid therapy on ER-α-under-expressing breast cancer cells. Drug resistance gene expression patterns were determined by RNA sequencing analysis and in vitro experiments. For the first time, we demonstrate that the combined treatment of pentadecanoic acid, an odd-chain fatty acid, and tamoxifen synergistically suppresses the growth of human breast carcinoma MCF-7 stem cells (MCF-7/SCs), which were found to be tamoxifen-resistant and showed reduced ER-α expression compared with the parental MCF-7 cells. In addition, the combined treatment synergistically induced apoptosis and accumulation of sub-G1 cells and suppressed epithelial-to-mesenchymal transition (EMT). Exposure to this combination induces re-expression of ER-α at the transcriptional and protein levels, along with suppression of critical survival signal pathways, such as ERK1/2, MAPK, EGFR, and mTOR. Collectively, decreased ER-α expression was restored by pentadecanoic acid treatment, resulting in reversal of tamoxifen resistance. Overall, pentadecanoic acid exhibits the potential to enhance the efficacy of endocrine therapy in the treatment of ER-α-under-expressing breast cancer cells.


Assuntos
Neoplasias da Mama , Tamoxifeno , Antineoplásicos Hormonais/farmacologia , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/metabolismo , Receptor alfa de Estrogênio/genética , Receptor alfa de Estrogênio/metabolismo , Ácidos Graxos/uso terapêutico , Feminino , Humanos , Células MCF-7 , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Serina-Treonina Quinases TOR , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico
8.
Pharmaceutics ; 14(5)2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35631492

RESUMO

Targeting cancer stem cell metabolism has emerged as a promising therapeutic strategy for cancer treatment. Breast cancer stem cells (BCSCs) exert distinct metabolism machinery, which plays a major role in radiation and multidrug resistance. Therefore, exploring the mechanisms involved in energy utilization of BCSCs could improve the effectiveness of therapeutic strategies aimed at their elimination. This study was conducted to clarify the glucose metabolism machinery and the function of nootkatone, a bioactive component of grapefruit, in regulating glucose metabolism and stemness characteristics in human breast carcinoma MCF-7 stem cells (MCF-7SCs). In vivo experiments, transcriptomic analysis, seahorse XF analysis, MTT assay, Western blotting, mammosphere formation, wound healing, invasion assay, flow cytometric analysis, reverse transcription-quantitative polymerase chain reaction, and in silico docking experiments were performed. MCF-7SCs showed a greater tumorigenic capacity and distinct gene profile with enrichment of the genes involved in stemness and glycolysis signaling pathways compared to parental MCF-7 cells, indicating that MCF-7SCs use glycolysis rather than oxidative phosphorylation (OXPHOS) for their energy supply. Nootkatone impaired glucose metabolism through AMPK activation and reduced the stemness characteristics of MCF-7SCs. In silico docking analysis demonstrated that nootkatone efficiently bound to the active site of AMPK. Therefore, this study indicates that regulation of glucose metabolism through AMPK activation could be an attractive target for BCSCs.

9.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22273675

RESUMO

BackgroundSARS-CoV-2 mutations conferring escape from neutralizing antibodies can arise in immunocompromised patients with prolonged infection, but the conditions that facilitate immune escape are still not fully understood. MethodsWe characterized endogenous immune responses, within-host SARS-CoV-2 evolution, and autologous neutralization of the viral variants that arose in five immunocompromised patients with prolonged infection and B cell deficiencies. ResultsIn two patients treated with the monoclonal antibody bamlanivimab, viral resistance to autologous serum arose early and persisted for several months, accompanied by ongoing evolution in the spike protein. These patients exhibited deficiencies in both T and B cell arms, and one patient succumbed to disease. In contrast, we did not observe spike mutations in immunologically important regions in patients who did not receive exogenous antibodies or who received convalescent plasma and had intact T cell responses to SARS-CoV-2. ConclusionsOur results underscore the potential importance of multiple factors - the absence of an effective endogenous immune response, persistent virus replication, and selective pressure such as single-agent bamlanivimab - in promoting the emergence of SARS-CoV-2 mutations associated with immune evasion. These findings highlight the need for larger clinical studies in immunocompromised populations to better understand the ramifications of different therapies. Our results also confirm that patients with B cell deficiencies can elicit effector T cells and may suggest an important role for T cells in controlling infection, which is relevant to vaccines and therapeutics.

10.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-488806

RESUMO

Background/objectivesCoronavirus disease 2019 (COVID-19) patients exhibit lipid metabolic alterations, but the mechanism remains unknown. In this study, we aimed to investigate whether the Spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) impairs lipid metabolism in host cells. MethodsA Spike cell line in HEK293 was generated using the pcDNA vector carrying the Spike gene expression cassette. A control cell line was generated using the empty pcDNA vector. Gene expression profiles related to lipid metabolic, autophagic, and ferroptotic pathways were investigated. Palmitic acid (PA)-overload was used to assess lipotoxicity-induced necrosis. ResultsAs compared with controls, the Spike cells showed a significant increase in lipid depositions on cell membranes as well as dysregulation of expression of a panel of molecules involved lipid metabolism, autophagy, and ferroptosis. The Spike cells showed an upregulation of nuclear factor erythroid 2-related factor 2 (Nrf2), a multifunctional transcriptional factor, in response to PA. Furthermore, the Spike cells exhibited increased necrosis in response to PA-induced lipotoxicity compared to control cells in a time- and dose-dependent manner via ferroptosis, which could be attenuated by the Nrf2 inhibitor trigonelline. ConclusionsThe Spike protein impairs lipid metabolic and autophagic pathways in host cells, leading to increased susceptibility to lipotoxicity via ferroptosis which can be suppressed by a Nrf2 inhibitor. This data also suggests a central role of Nrf2 in Spike-induced lipid metabolic impairments. HighlightsO_LIThe Spike protein increases lipid deposition in host cell membranes C_LIO_LIThe Spike protein impairs lipid metabolic and autophagic pathways C_LIO_LIThe Spike protein exaggerates PA-induced lipotoxicity in host cells via ferroptosis C_LIO_LINrf2 inhibitor Trigonelline can mitigate the Spike protein-induced necrosis C_LI

11.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-22270699

RESUMO

BackgroundThe goal of this study was to characterize the ability of school-aged children to self-collect adequate anterior nares (AN) swabs for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing. MethodsFrom July to August 2021, 287 children, age 4-14 years-old, were prospectively enrolled in the Atlanta area. Symptomatic (n=197) and asymptomatic (n=90) children watched a short instructional video before providing a self-collected AN specimen. Health care workers (HCWs) then collected a second specimen, and useability was assessed by the child and HCW. Swabs were tested side-by-side for SARS-CoV-2. RNase P RNA detection was investigated as a measure of specimen adequacy. ResultsAmong symptomatic children, 87/196 (44.4%) tested positive for SARS-CoV-2 by both self- and HCW-swab. Two children each were positive by self- or HCW-swab; one child had an invalid HCW-swab. Compared to HCW-swabs, self-collected swabs had 97.8% and 98.1% positive and negative percent agreements, respectively, and SARS-CoV-2 Ct values did not differ significantly between groups. Participants [≤]8 years-old were less likely than those >8 to be rated as correctly completing self-collection, but SARS-CoV-2 detection did not differ. Based on RNase P RNA detection, 270/287 children (94.1%) provided adequate self-swabs versus 277/287 (96.5%) HCW-swabs (p=0.24) with no difference when stratified by age. ConclusionsChildren, aged 4-14 years-old, can provide adequate AN specimens for SARS-CoV-2 detection when presented with age-appropriate instructional material, consisting of a video and a handout, at a single timepoint. These data support the use of self-collected AN swabs among school-age children for SARS-CoV-2 testing.

12.
Radiol Case Rep ; 17(3): 685-689, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35003460

RESUMO

Gliosarcoma (GS) is an uncommon central nervous system tumor with several characteristics of a malignant neoplasm and poor prognosis. The majority of GS reports describe a predilection for the cerebral hemispheres, and cases of intraventricular GS are extremely rare, with only a few reported. In addition, intraventricular GS has not been associated with any unique radiographic or clinical features, which can result in misdiagnosis as other intraventricular tumor types. In this report, we present the case of a 32-year-old woman with GS in the trigone of the lateral ventricle and provide a retrospective review of similar, previously reported cases.

13.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-473557

RESUMO

The BNT162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna) vaccines generate potent neutralizing antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the global emergence of SARS-CoV-2 variants with mutations in the spike protein, the principal antigenic target of these vaccines, has raised concerns over the neutralizing activity of vaccine-induced antibody responses. The Omicron variant, which emerged in November 2021, consists of over 30 mutations within the spike protein. Here, we used an authentic live virus neutralization assay to examine the neutralizing activity of the SARS-CoV-2 Omicron variant against mRNA vaccine-induced antibody responses. Following the 2nd dose, we observed a 30-fold reduction in neutralizing activity against the omicron variant. Through six months after the 2nd dose, none of the sera from naive vaccinated subjects showed neutralizing activity against the Omicron variant. In contrast, recovered vaccinated individuals showed a 22-fold reduction with more than half of the subjects retaining neutralizing antibody responses. Following a booster shot (3rd dose), we observed a 14-fold reduction in neutralizing activity against the omicron variant and over 90% of boosted subjects showed neutralizing activity against the omicron variant. These findings show that a 3rd dose is required to provide robust neutralizing antibody responses against the Omicron variant.

14.
Elife ; 102021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34581270

RESUMO

Background: Cryptococcal meningitis has high mortality. Flucytosine is a key treatment but is expensive and rarely available. The anticancer agent tamoxifen has synergistic anti-cryptococcal activity with amphotericin in vitro. It is off-patent, cheap, and widely available. We performed a trial to determine its therapeutic potential. Methods: Open label randomized controlled trial. Participants received standard care - amphotericin combined with fluconazole for the first 2 weeks - or standard care plus tamoxifen 300 mg/day. The primary end point was Early Fungicidal Activity (EFA) - the rate of yeast clearance from cerebrospinal fluid (CSF). Trial registration https://clinicaltrials.gov/ct2/show/NCT03112031. Results: Fifty patients were enrolled (median age 34 years, 35 male). Tamoxifen had no effect on EFA (-0.48log10 colony-forming units/mL/CSF control arm versus -0.49 tamoxifen arm, difference -0.005log10CFU/ml/day, 95% CI: -0.16, 0.15, p=0.95). Tamoxifen caused QTc prolongation. Conclusions: High-dose tamoxifen does not increase the clearance rate of Cryptococcus from CSF. Novel, affordable therapies are needed. Funding: The trial was funded through the Wellcome Trust Asia Programme Vietnam Core Grant 106680 and a Wellcome Trust Intermediate Fellowship to JND grant number WT097147MA.


Assuntos
Anfotericina B/uso terapêutico , Cryptococcus neoformans/efeitos dos fármacos , Fluconazol/uso terapêutico , Meningite Criptocócica/tratamento farmacológico , Tamoxifeno/uso terapêutico , Adulto , Antifúngicos/uso terapêutico , Quimioterapia Combinada , Feminino , Humanos , Síndrome do QT Longo/induzido quimicamente , Masculino , Meningite Criptocócica/líquido cefalorraquidiano , Meningite Criptocócica/metabolismo , Tamoxifeno/efeitos adversos
15.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21263618

RESUMO

ObjectivesThe objective of the current study was to develop a lower-cost and scalable protocol to identify and monitor SARS-CoV-2 variants in Paraguay by pairing real-time RT-PCR detection of spike mutations with amplicon Sanger sequencing and whole-genome Nanopore sequencing. Methods201 acute-phase nasopharyngeal samples from SARS-CoV-2-positive individuals were tested with two rRT-PCRs: 1) N2RP assay to confirm SARS-CoV-2 RNA detection (CDC N2 target), and 2) the Spike SNP assay to detect mutations in the spike receptor binding domain. The assay was performed with probes to identify mutations associated with the following variants: alpha (501Y), beta/gamma (417variant/484K/501Y), delta (452R/478K), and lambda (452Q/490S). ResultsAll samples were positive for SARS-CoV-2 in the N2RP assay (mean Ct, 20.8; SD 5.6); 198/201 (98.5%) tested positive in the Spike SNP assay. The most common genotype was 417variant/484K/501Y, detected in 102/198 samples (51.5%) and most consistent with P.1 lineage (gamma variant) in Paraguay. No mutations (K417 only) were found in 64/198 (32.3%); and K417/484K was identified in 22/198 (11.1%), consistent with P.2 (zeta). Seven samples (3.5%) tested positive for 452R without 478K, and one sample with genotype K417/501Y was confirmed as B.1.1.7 (alpha). Results were confirmed by Sanger sequencing in 181/181 samples (100%) with high-quality amplicon sequences, and variant calls were consistent with Nanopore sequencing in 29/29 samples. ConclusionsThe Spike SNP assay provides accurate detection of mutations associated with SARS-CoV-2 variants. This can be implemented in laboratories performing rRT-PCR to improve population-level surveillance for these mutations and inform the judicious use of scarce sequencing resources.

16.
Pharmaceuticals (Basel) ; 14(8)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34451892

RESUMO

Ampelopsin, also known as dihydromyricetin, is a commonly found flavonoid in medicinal plants. The cancer stem cell (CSC) population is a promising target for triple-negative breast cancer (TNBC). In this study, flavonoid screening was performed in the established MDA-MB-231/IR cell line, which is enriched in CSCs. Ampelopsin suppressed the proliferation and colony formation of stem cell-rich MDA-MB-231/IR, while inducing their apoptosis. Importantly, ampelopsin displayed an inhibitory impact on the stemness features of MDA-MB-231/IR cells, demonstrated by decreases in mammosphere formation, the CD44+/CD24-/low population, aldehyde dehydrogenase activity, and the levels of stem cell markers (e.g., CD44, MRP1, ß-catenin, and KLF4). Ampelopsin also suppressed the epithelial-mesenchymal transition, as evidenced by decreases in migration, invasion capacity, and mesenchymal markers, as well as an increase in the epithelial marker E-cadherin. Moreover, ampelopsin significantly impaired oxidative phosphorylation by reducing the oxygen consumption rate and adenosine triphosphate production in MDA-MB-231/IR cells. Notably, ampelopsin treatment significantly reduced the levels of the phosphorylated forms of IκBα and NF-κB p65, as well as the levels of tumor necrosis factor (TNF)-α-stimulated phosphorylation of IκBα and NF-κB p65. These results demonstrated that ampelopsin prevents the TNF-α/NF-κB signaling axis in breast CSCs.

17.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-414706

RESUMO

BackgroundCoronavirus disease 2019 (COVID-19) patients exhibit multiple organ malfunctions with a primary manifestation of acute and diffuse lung injuries. The Spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is crucial to mediate viral entry into host cells; however, whether it can be cellularly pathogenic and contribute to pulmonary hyper-inflammations in COVID-19 is not well known. Methods and FindingsIn this study, we developed a Spike protein-pseudotyped (Spp) lentivirus with the proper tropism of SARS-CoV-2 Spike protein on the surface and tracked down the fate of Spp in wild type C57BL/6J mice receiving intravenous injection of the virus. A lentivirus with vesicular stomatitis virus glycoprotein (VSV-G) was used as the control. Two hours post-infection (hpi), Spp showed more than 27-75 times more viral burden in the lungs than other organs; it also exhibited about 3-5 times more viral burden than VSV-G lentivirus in the lungs, liver, kidney and spleen. Acute pneumonia was evident in animals 24 hpi. Spp lentivirus was mainly found in LDLR+ macrophages and pneumocytes in the lungs, but not in MARC1+ macrophages. IL6, IL10, CD80 and PPAR-{gamma} were quickly upregulated in response to infection of Spp lentivirus in the lungs in vivo as well as in macrophage-like RAW264.7 cells in vitro. We further confirmed that forced expression of the Spike protein in RAW264.7 cells could significantly increase the mRNA levels of the same panel of inflammatory factors. ConclusionsOur results demonstrate that the Spike protein of SARS-CoV-2 alone can induce cellular pathology, e.g. activating macrophages and contributing to induction of acute inflammatory responses.

18.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20245977

RESUMO

COVID-19 patients develop hypolipidemia. However, it is unknown whether lipid levels have improved in recovered patients. In this study, a 3-6 month follow-up study was performed to examine serum levels of laboratory values in 107 discharged COVID-19 patients (mild = 59; severe/critical = 48; diagnoses on admission). 61 patients had a revisit chest CT scan. A Wilcoxon signed-rank test was used to analyze changes in laboratory values. LDL-c and HDL-c levels were significantly higher at follow-up than at admission in severe/critical cases (p < 0.05). LDL-c levels were significantly higher at follow-up than at admission in mild cases (p < 0.05). With adjustment of the factor of traditional Chinese medicine, LDL-c and HDL-c levels were significantly improved at follow-up than at admission in severe/critical cases (p < 0.05). Increases in HDL-c significantly correlated with increases in numbers of white blood cells (p<0.001) and decreases in levels of C-reactive protein (p < 0.05) during patients recovery. Residue lesions were observed in CT images in 69% (42 of 61) of follow-up patients. We concluded that improvements of LDL-c, HDL-c and incomplete absorption of lung lesions were observed at follow-up for recovered patients, indicating that a long-term recovery process could be required.

19.
Artigo em Inglês | MEDLINE | ID: mdl-33139294

RESUMO

Optimal dosing of children with tuberculous meningitis (TBM) remains uncertain and is currently based on the treatment of pulmonary tuberculosis in adults. This study aimed to investigate the population pharmacokinetics of isoniazid, rifampin, pyrazinamide, and ethambutol in Vietnamese children with TBM, to propose optimal dosing in these patients, and to determine the relationship between drug exposure and treatment outcome. A total of 100 Vietnamese children with TBM were treated with an 8-month antituberculosis regimen. Nonlinear mixed-effects modeling was used to evaluate the pharmacokinetic properties of the four drugs and to simulate different dosing strategies. The pharmacokinetic properties of rifampin and pyrazinamide in plasma were described successfully by one-compartment disposition models, while those of isoniazid and ethambutol in plasma were described by two-compartment disposition models. All drug models included allometric scaling of body weight and enzyme maturation during the first years of life. Cerebrospinal fluid (CSF) penetration of rifampin was relatively poor and increased with increasing protein levels in CSF, a marker of CSF inflammation. Isoniazid and pyrazinamide showed good CSF penetration. Currently recommended doses of isoniazid and pyrazinamide, but not ethambutol and rifampin, were sufficient to achieve target exposures. The ethambutol dose cannot be increased because of ocular toxicity. Simulation results suggested that rifampin dosing at 50 mg/kg of body weight/day would be required to achieve the target exposure. Moreover, low rifampin plasma exposure was associated with an increased risk of neurological disability. Therefore, higher doses of rifampin could be considered, but further studies are needed to establish the safety and efficacy of increased dosing.


Assuntos
Antituberculosos , Tuberculose Meníngea , Adulto , Antituberculosos/uso terapêutico , Povo Asiático , Criança , Etambutol , Humanos , Isoniazida , Pirazinamida , Tuberculose Meníngea/tratamento farmacológico
20.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-20163824

RESUMO

Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), became a pandemic in early 2020. Lateral flow immunoassays for antibody testing have been viewed as a cheap and rapidly deployable method for determining previous infection with SARS-CoV-2; however, these assays have shown unacceptably low sensitivity. We report on nine lateral flow immunoassays currently available and compare their titer sensitivity in serum to a best-practice enzyme-linked immunosorbent assay (ELISA) and viral neutralization assay. For a small group of PCR-positive, we found two lateral flow immunoassay devices with titer sensitivity roughly equal to the ELISA; these devices were positive for all PCR-positive patients harboring SARS-CoV-2 neutralizing antibodies. One of these devices was deployed in Northern Italy to test its sensitivity and specificity in a real-world clinical setting. Using the device with fingerstick blood on a cohort of 27 hospitalized PCR-positive patients and seven hospitalized controls, ROC curve analysis gave AUC values of 0.7646 for IgG. For comparison, this assay was also tested with saliva from the same patient population and showed reduced discrimination between cases and controls with AUC values of 0.6841 for IgG. Furthermore, during viral neutralization testing, one patient was discovered to harbor autoantibodies to ACE2, with implications for how immune responses are profiled. We show here through a proof-of-concept study that these lateral flow devices can be as analytically sensitive as ELISAs and adopted into hospital protocols; however, additional improvements to these devices remain necessary before their clinical deployment.

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