Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 69
Filtrar
1.
Genesis ; 62(2): e23597, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38590121

RESUMO

Sensory signals detected by olfactory sensory organs are critical regulators of animal behavior. An accessory olfactory organ, the vomeronasal organ, detects cues from other animals and plays a pivotal role in intra- and inter-species interactions in mice. However, how ethologically relevant cues control mouse behavior through approximately 350 vomeronasal sensory receptor proteins largely remains elusive. The type 2 vomeronasal receptor-A4 (V2R-A4) subfamily members have been repeatedly detected from vomeronasal sensory neurons responsive to predator cues, suggesting a potential role of this receptor subfamily as a sensor for predators. This review focuses on this intriguing subfamily, delving into its receptor functions and genetic characteristics.


Assuntos
Bulbo Olfatório , Órgão Vomeronasal , Camundongos , Animais , Bulbo Olfatório/fisiologia , Células Receptoras Sensoriais/metabolismo , Órgão Vomeronasal/metabolismo
2.
Nat Med ; 30(5): 1292-1299, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38632391

RESUMO

Targeted tissue ablation involving the anterior hippocampus is the standard of care for patients with drug-resistant mesial temporal lobe epilepsy. However, a substantial proportion continues to suffer from seizures even after surgery. We identified the fasciola cinereum (FC) neurons of the posterior hippocampal tail as an important seizure node in both mice and humans with epilepsy. Genetically defined FC neurons were highly active during spontaneous seizures in epileptic mice, and closed-loop optogenetic inhibition of these neurons potently reduced seizure duration. Furthermore, we specifically targeted and found the prominent involvement of FC during seizures in a cohort of six patients with epilepsy. In particular, targeted lesioning of the FC in a patient reduced the seizure burden present after ablation of anterior mesial temporal structures. Thus, the FC may be a promising interventional target in epilepsy.


Assuntos
Hipocampo , Neurônios , Animais , Hipocampo/patologia , Humanos , Camundongos , Neurônios/patologia , Epilepsia/patologia , Masculino , Optogenética , Feminino , Convulsões , Epilepsia do Lobo Temporal/fisiopatologia , Epilepsia do Lobo Temporal/patologia , Adulto
3.
Respir Res ; 25(1): 161, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38614991

RESUMO

BACKGROUND: Longitudinal studies have identified childhood asthma as a risk factor for obstructive pulmonary disease (COPD) and asthma-COPD overlap (ACO) where persistent airflow limitation can develop more aggressively. However, a causal link between childhood asthma and COPD/ACO remains to be established. Our study aimed to model the natural history of childhood asthma and COPD and to investigate the cellular/molecular mechanisms that drive disease progression. METHODS: Allergic airways disease was established in three-week-old young C57BL/6 mice using house dust mite (HDM) extract. Mice were subsequently exposed to cigarette smoke (CS) and HDM for 8 weeks. Airspace enlargement (emphysema) was measured by the mean linear intercept method. Flow cytometry was utilised to phenotype lung immune cells. Bulk RNA-sequencing was performed on lung tissue. Volatile organic compounds (VOCs) in bronchoalveolar lavage-fluid were analysed to screen for disease-specific biomarkers. RESULTS: Chronic CS exposure induced emphysema that was significantly augmented by HDM challenge. Increased emphysematous changes were associated with more abundant immune cell lung infiltration consisting of neutrophils, interstitial macrophages, eosinophils and lymphocytes. Transcriptomic analyses identified a gene signature where disease-specific changes induced by HDM or CS alone were conserved in the HDM-CS group, and further revealed an enrichment of Mmp12, Il33 and Il13, and gene expression consistent with greater expansion of alternatively activated macrophages. VOC analysis also identified four compounds increased by CS exposure that were paradoxically reduced in the HDM-CS group. CONCLUSIONS: Early-life allergic airways disease worsened emphysematous lung pathology in CS-exposed mice and markedly alters the lung transcriptome.


Assuntos
Asma , Fumar Cigarros , Enfisema , Hipersensibilidade , Enfisema Pulmonar , Humanos , Animais , Camundongos , Camundongos Endogâmicos C57BL , Pyroglyphidae , Fumar Cigarros/efeitos adversos , Enfisema Pulmonar/etiologia , Inflamação
4.
Carbohydr Polym ; 334: 122043, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38553239

RESUMO

Here, we prepared ionically crosslinked films using pectin extracted from agro-wastes, specifically ambarella peels (AFP) and jackfruit seed slimy sheath (JFS). Physiochemical properties of pectins, including moisture content, molecular weight (Mw), degree of esterification (DE), and galacturonic acid (GA), were analyzed. Optimal extraction was determined, i.e., citric acid concentration 0.3 M, time 60 min, solid/liquid ratio 1:25, and temperature 90 °C for AFP or 85 °C for JFS. Pectin yields under these conditions were 29.67 % ± 0.35 % and 29.93 ± 0.49 %, respectively. AFP pectin revealed Mw, DE, and GA values of 533.20 kDa, 67.08 % ± 0.68 %, and 75.39 ± 0.82 %, while JFS pectin exhibited values of 859.94 kDa, 63.04 % ± 0.47 %, and 78.63 % ± 0.71 %, respectively. The pectin films crosslinked with Ca2+, Cu2+, Fe3+, or Zn2+ exhibited enhanced tensile strength and Young's modulus, along with reduced elongation at break, moisture content, water solubility, water vapor permeability, and oxygen permeability. Structural analyses indicated metal ions were effectively crosslinked with carboxyl groups of pectin. Notably, the Cu2+-crosslinked film demonstrated superior water resistance, mechanical properties, and exhibited the highest antioxidant and antibacterial activities among all tested films. Therefore, the pectin films represent a promising avenue to produce eco-friendly food packaging materials with excellent properties.


Assuntos
Artocarpus , Pectinas , Artocarpus/química , Embalagem de Alimentos , Frutas/química , Íons/análise , Pectinas/química , Sementes
5.
Data Brief ; 52: 110046, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38299106

RESUMO

Rice holds a significant position in the global food supply chain, particularly in Asian, African, and Latin American countries. However, rice pests and diseases cause significant damage to the supply and growth of the rice cultivation industry. Therefore, this article provides a high-quality dataset that has been reviewed by agricultural experts. The dataset is well-suited to support the development of automation systems and smart farming practices. It plays a vital role in facilitating the automatic construction, detection, and classification of rice diseases. However, challenges arise due to the diversity of the dataset collected from various sources, varying in terms of disease types and sizes. This necessitates support for upgrading and enhancing the dataset through various operations in data processing, preprocessing, and statistical analysis. The dataset is provided completely free of charge and has been rigorously evaluated by agricultural experts, making it a reliable resource for system development, research, and communication needs.

6.
Nat Commun ; 15(1): 601, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38238329

RESUMO

Epilepsy is a prevalent disorder involving neuronal network hyperexcitability, yet existing therapeutic strategies often fail to provide optimal patient outcomes. Chemogenetic approaches, where exogenous receptors are expressed in defined brain areas and specifically activated by selective agonists, are appealing methods to constrain overactive neuronal activity. We developed BARNI (Bradanicline- and Acetylcholine-activated Receptor for Neuronal Inhibition), an engineered channel comprised of the α7 nicotinic acetylcholine receptor ligand-binding domain coupled to an α1 glycine receptor anion pore domain. Here we demonstrate that BARNI activation by the clinical stage α7 nicotinic acetylcholine receptor-selective agonist bradanicline effectively suppressed targeted neuronal activity, and controlled both acute and chronic seizures in male mice. Our results provide evidence for the use of an inhibitory acetylcholine-based engineered channel activatable by both exogenous and endogenous agonists as a potential therapeutic approach to treating epilepsy.


Assuntos
Epilepsia , Receptores Nicotínicos , Camundongos , Masculino , Humanos , Animais , Receptores Colinérgicos , Receptor Nicotínico de Acetilcolina alfa7/genética , Receptores Nicotínicos/genética , Agonistas Nicotínicos/farmacologia , Acetilcolina/farmacologia , Convulsões/genética
7.
bioRxiv ; 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-37808690

RESUMO

Animals have the innate ability to select optimal defensive behavioral outputs with an appropriate intensity in response to predator threat in specific contexts. Such innate behavioral decisions are thought to be computed in the medial hypothalamic nuclei that contain neural populations directly controlling defensive behavioral outputs. The vomeronasal organ (VNO) is one of the major sensory input channels through which predator cues are detected with ascending inputs to the medial hypothalamic nuclei, especially to the ventromedial hypothalamus (VMH), through the medial amygdala (MeA) and bed nucleus of the stria terminalis (BNST). Here, we show that cat saliva contains predator cues that signal imminence of predator threat and regulate the robustness of freezing behavior through the VNO in mice. Cat saliva activates neurons expressing the V2R-A4 subfamily of sensory receptors, suggesting the existence of specific receptor groups responsible for freezing behavior induced by the predator cues. The number of VNO neurons activated in response to saliva correlates with the freshness of saliva and the intensity of freezing behavior, while the downstream neurons in the accessory olfactory bulb (AOB) and defensive behavioral circuit are quantitatively equally activated by fresh and old saliva. Strikingly, however, only the number of VMH neurons activated by fresh saliva positively correlates with the intensity of freezing behavior. Detailed analysis of the spatial distribution of fresh and old saliva-responding neurons revealed a neuronal population within the VMH that is more sensitive to fresh saliva than old saliva. Taken together, this study demonstrates that predator cues in cat saliva change over time and differentially activate the sensory-to-hypothalamus defensive behavioral pathway to modulate behavioral outputs.

8.
Phys Chem Chem Phys ; 25(37): 25389-25397, 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37705426

RESUMO

Density functional theory (DFT) calculations were utilized to investigate the electrocatalytic potential of single boron (B) atom doping in defective ReS2 monolayers as an active site. Our investigation revealed that B-doped defective ReS2, containing S and S-Re-S defects, demonstrated remarkable conductivity, and emerged as an exceptionally active catalyst for nitrogen reduction reactions (NRR), exhibiting limiting potentials of 0.63 and 0.53 V, respectively. For both cases, we determined the potential by examining the hydrogenation of adsorbed N2* to N2H*. Although the competing hydrogen evolution reaction (HER) process appeared dominant in the S-Re-S defect case, its impact was minimal. The outstanding NRR performance can be ascribed to the robust chemical interactions between B and N atoms. The adsorption of N2 on B weakens the N-N bond, thereby facilitating the formation of NH3. Moreover, we verified the selectivity and stability of the catalysts for NRR. Our findings indicate that B-doped defective ReS2 monolayers hold considerable promise for electrocatalysis in a variety of applications.

9.
Front Oncol ; 13: 1054406, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37182141

RESUMO

Introduction: Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) are considered for patients with peritoneal metastasis (PM). However, patients selection that relies on conventional prognostic factors is not yet optimal. In this study, we performed whole exome sequencing (WES) to establish tumor molecular characteristics and expect to identify prognosis profiles for PM management. Methods: In this study, blood and tumor samples were collected from patients with PM before HIPEC. Tumor molecular signatures were determined using WES. Patient cohort was divided into responders and non-responders according to 12-month progression-free survival (PFS). Genomic characteristics between the two cohorts were compared to study potential targets. Results: In total, 15 patients with PM were enrolled in this study. Driver genes and enriched pathways were identified from WES results. AGAP5 mutation was found in all responders. This mutation was significantly associated with better OS (p = 0.00652). Conclusions: We identified prognostic markers that might be useful to facilitate decision-making before CRS/HIPEC.

10.
Front Psychiatry ; 14: 1089473, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37091696

RESUMO

Background: While depression is a common mental disorder, the diagnosis of this condition is still challenging. Thus, there is a need to have a validated tool to help evaluate symptoms of depression. This study aimed to evaluate the reliability and validity of the Vietnamese version of the Hamilton D-17 scale. Methods: A cross-sectional, descriptive, and validation study was conducted on 183 patients including 139 depressed and 44 non-depressed patients at the University Medical Center of Medicine and Pharmacy University at Ho Chi Minh City. Internal reliability and inter-rater reliability was measured using Cronbach's alpha and intraclass correlation coefficients (ICC). Confirmatory factor analysis (CFA) was used to evaluate construct validity. The Patient Health Questionnaire (PHQ9) was used to measure concurrent validity of the Hamilton D-17. Area under the ROC curve was used to measure criterion validity. Results: Both Cronbach alpha coefficient and ICC were at good level at alpha = 0.83 and ICC = 0.83. CFA with a second-order model consisting of four factors fitted the data at good to excellent level. The SRMR (Standardized Root Mean Squared Residual) was 0.066, RMSEA (Root Mean Square Error of Approximation) (90% CI) was 0.053 (0.036-0.069), CFI (comparative fit index) was 0.93, TLI (Tucker Lewis index) was 0.92. The Hamilton D-17 and the PHQ-9 had a correlation coefficient of r = 0.77 (p < 0.001). The Hamilton D-17 had a very high level of criterion validity with AUC of 0.93 (0.88-0.98). Conclusion: The Vietnamese version of the Hamilton D-17 scale has a high level of validity and reliability. The scale should be used to assess symptoms of depression among Vietnamese patients.

11.
Front Immunol ; 14: 1113478, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36891299

RESUMO

Helicobacter pylori has developed several strategies using its diverse virulence factors to trigger and, at the same time, limit the host's inflammatory responses in order to establish a chronic infection in the human stomach. One of the virulence factors that has recently received more attention is a member of the Helicobacter outer membrane protein family, the adhesin HopQ, which binds to the human Carcinoembryonic Antigen-related Cell Adhesion Molecules (CEACAMs) on the host cell surface. The HopQ-CEACAM interaction facilitates the translocation of the cytotoxin-associated gene A (CagA), an important effector protein of H. pylori, into host cells via the Type IV secretion system (T4SS). Both the T4SS itself and CagA are important virulence factors that are linked to many aberrant host signaling cascades. In the last few years, many studies have emphasized the prerequisite role of the HopQ-CEACAM interaction not only for the adhesion of this pathogen to host cells but also for the regulation of cellular processes. This review summarizes recent findings about the structural characteristics of the HopQ-CEACAM complex and the consequences of this interaction in gastric epithelial cells as well as immune cells. Given that the upregulation of CEACAMs is associated with many H. pylori-induced gastric diseases including gastritis and gastric cancer, these data may enable us to better understand the mechanisms of H. pylori's pathogenicity.


Assuntos
Proteínas de Bactérias , Helicobacter pylori , Humanos , Proteínas de Bactérias/genética , Antígenos de Bactérias/genética , Transporte Proteico , Adesinas Bacterianas/metabolismo , Estômago , Fatores de Virulência/metabolismo
12.
Sci Total Environ ; 872: 162199, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-36791847

RESUMO

Nitrofurans are broad-spectrum bactericidal agents used in a large quantity for veterinary and human therapy. This study reports the long-term impact of two nitrofuran representatives, nitrofurantoin (NFT) and furaltadone (FTD) on the bacterial strains Sphingobacterium siyangense FTD2, Achromobacter pulmonis NFZ2, and Stenotrophomonas maltophilia FZD2, isolated from a full-scale wastewater treatment plant. Bacterial whole genome sequencing was used for preliminary strains characterization. The metabolomic, electrochemical, and culture methods were applied to understand changes in the bacterial strains after 12-month exposure to nitrofurans. The most significantly altered metabolic pathways were observed in amino acid and sugar metabolism, and aminoacyl-tRNA biosynthesis. Disrupted protein biosynthesis was measured in all strains treated with antibiotics. Prolonged exposure to NFT and FTD also triggered mutagenic effects, affected metabolic activity, and facilitated oxidative stress within the cells. Nitrofuran-induced oxidative stress was evidenced from an elevated activity of catalase and glutathione S-transferases. NFT and FTD elicited similar but not identical responses in all analyzed strains. The results obtained in this study provide new insights into the potential risks of the prolonged presence of antimicrobial compounds in the environment and contribute to a better understanding of the possible impacts of nitrofuran antibiotics on the bacterial cells.


Assuntos
Demência Frontotemporal , Nitrofuranos , Humanos , Águas Residuárias , Nitrofuranos/análise , Nitrofuranos/metabolismo , Nitrofuranos/farmacologia , Antibacterianos/metabolismo , Bactérias/metabolismo
13.
Nat Commun ; 13(1): 7186, 2022 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-36418348

RESUMO

High levels of the inflammatory cytokine IL-6 in the bone marrow are associated with poor outcomes in pediatric acute myeloid leukemia (pAML), but its etiology remains unknown. Using RNA-seq data from pre-treatment bone marrows of 1489 children with pAML, we show that > 20% of patients have concurrent IL-6, IL-1, IFNα/ß, and TNFα signaling activity and poorer outcomes. Targeted sequencing of pre-treatment bone marrow samples from affected patients (n = 181) revealed 5 highly recurrent patterns of somatic mutation. Using differential expression analyses of the most common genomic subtypes (~60% of total), we identify high expression of multiple potential drivers of inflammation-related treatment resistance. Regardless of genomic subtype, we show that JAK1/2 inhibition reduces receptor-mediated inflammatory signaling by leukemic cells in-vitro. The large number of high-risk pAML genomic subtypes presents an obstacle to the development of mutation-specific therapies. Our findings suggest that therapies targeting inflammatory signaling may be effective across multiple genomic subtypes of pAML.


Assuntos
Medula Óssea , Leucemia Mieloide Aguda , Humanos , Criança , Medula Óssea/metabolismo , Interleucina-6/metabolismo , Transdução de Sinais/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo
14.
Sci Rep ; 12(1): 18812, 2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36335280

RESUMO

Two lanthanide metal-organic frameworks [Ln-MOFs, Ln = Eu(III), Tb(III)] composed of oxalic acid and Ln building units were hydrothermally synthesized and fully characterized by powder X-ray diffraction, Fourier-transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscope, and energy-dispersive X-ray spectroscopy. Furthermore, their magnetic susceptibility measurements were obtained using SQUID based vibrating sample magnetometer (MPMS 3, Quantum Design). Both Ln-MOFs exhibited highly efficient luminescent property. Solid-state photoluminescence (PL) measurements revealed phosphorescence emission bands of Eu-MOF and Tb-MOF centered at 618 nm (red emission) and 550 nm (green emission) upon excitation at 396 nm and 285 nm, respectively. Eu-MOF and Tb-MOF displayed a phosphorescence quantum yield of 53% and 40%, respectively. Time-resolved PL analyses showed very long lifetime values, at 600 and 1065 ± 1 µs for Eu-MOF and Tb-MOF, respectively. Calculations performed by density functional theory indicated a charge transfer form metal centres to the ligand which was in good agreement with the experimental studies. Therefore, this new mode of highly photoluminescent MOF materials is studied for the first time which paves the way for better understanding of these systems for potential applications.

15.
Environ Sci Technol ; 56(12): 8197-8208, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35675163

RESUMO

This work examined the chiral inversion of 2-arylpropionic acids (2-APAs) under anaerobic conditions and the associated microbial community. The anaerobic condition was simulated by two identical anaerobic digesters. Each digester was fed with the substrate containing 11 either pure (R)- or pure (S)-2-APA enantiomers. Chiral inversion was evidenced by the concentration increase of the other enantiomer in the digestate and the changes in the enantiomeric fraction between the two enantiomers. Both digesters showed similar and poor removal of 2-APAs (≤30%, except for naproxen) and diverse chiral inversion behaviors under anaerobic conditions. Four compounds exhibited (S → R) unidirectional inversion [flurbiprofen, ketoprofen, naproxen, and 2-(4-tert-butylphenyl)propionic acid], and the remaining seven compounds showed bidirectional inversion. Several aerobic and facultative anaerobic bacterial genera (Candidatus Microthrix, Rhodococcus, Mycobacterium, Gordonia, and Sphingobium) were identified in both digesters and predicted to harbor the 2-arylpropionyl-CoA epimerase (enzyme involved in chiral inversion) encoding gene. These genera presented at low abundances, <0.5% in the digester dosed with (R)-2-APAs and <0.2% in the digester dosed with (S)-2-APAs. The low abundances of these genera explain the limited extent of chiral inversion observed in this study.


Assuntos
Flurbiprofeno , Naproxeno , Anaerobiose , Anti-Inflamatórios não Esteroides , Estereoisomerismo
16.
J Am Coll Health ; : 1-8, 2022 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-35737974

RESUMO

OBJECTIVE: This study aims to examine the relationship between nature relatedness (NR) on subjective positive well-being (life satisfaction) and mental disorders (depression, stress, and anxiety) in Vietnamese university students. PARTICIPANTS: 340 Hue University students voluntarily took part in the survey. METHODS: The Nature Relatedness Scale, Depression, Anxiety, and Stress Scale and Satisfaction with Life Scale were used. Bivariate correlation, single regression, and moderation analysis were conducted to investigate the relationship between NR and the mental health of university students and the moderating role of NR. RESULTS: Higher levels of NR significantly predicted higher levels of life satisfaction but did not significantly predict fewer symptoms of depression, anxiety, and stress. NR significantly moderated the link between life satisfaction and depression, anxiety, and stress. CONCLUSIONS: The findings of this study imply that efforts to enhance students' mental health should include efforts to promote their NR.

17.
Int J Health Plann Manage ; 37(5): 2852-2868, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35607717

RESUMO

The COVID-19 pandemic has aggravated the obstacles for HIV/AIDS programs in limited-resource countries like Vietnam to achieve the HIV/AIDS-related Sustainable Development target. The paper aims to evaluate the impact of the COVID-19 pandemic on the provision of HIV/AIDS services-a pathway to achieving universal health coverage for key populations (KPs). Employing mix-methods, we conducted a desk study, one focus group discussion, and ten in-depth interviews with participants from the Ministry of Health, Provincial Centres for Disease Control, and HIV/AIDS-related facilities. The results showed the reduced coverage of KPs with access to prevention (i.e., harm-reduction services, counselling), testing, and treatment services (i.e., antiretroviral therapy, isoniazid preventive therapy). It also showed the reduced coverage of quality essential services, mainly in skipping consultation and testing, delaying un-emergency services, and redirecting KPs to non-HIV-specialised facilities. There was a gap in providing support for mental health, violence/abuse, and reproductive health. Financial risk protection for KPs was reduced due to uncertain local budget allocation; decreasing their ability to pay for HIV/AIDS-related services and social health insurance premiums; and increased out-of-pocket payments to comply with the COVID-19 control measures. This paper provides recommendations for strategic planning to ensure universal health coverage for KPs in the post COVID-19 era, especially for limited-resource countries like Vietnam.


Assuntos
Síndrome da Imunodeficiência Adquirida , COVID-19 , Infecções por HIV , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Humanos , Pandemias/prevenção & controle , Cobertura Universal do Seguro de Saúde
18.
Clin Chim Acta ; 531: 309-317, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35500877

RESUMO

BACKGROUND: Asymptomatic transmission was found to be the Achilles' heel of the symptom-based screening strategy, necessitating the implementation of mass testing to efficiently contain the transmission of COVID-19 pandemic. However, the global shortage of molecular reagents and the low throughput of available realtime PCR facilities were major limiting factors. METHODS: A novel semi-nested and heptaplex (7-plex) RT-PCR assay with melting analysis for detection of SARS-CoV-2 RNA has been established for either individual testing or 96-sample pooled testing. The complex melting spectrum collected from the heptaplex RT-PCR amplicons was interpreted with the support of an artificial intelligence algorithm for the detection of SARS-CoV-2 RNA. The analytical and clinical performance of the semi-nested RT-PCR assay was evaluated using RNAs synthesized in-vitro and those isolated from nasopharyngeal samples. RESULTS: The LOD of the assay for individual testing was estimated to be 7.2 copies/reaction. Clinical performance evaluation indicated a sensitivity of 100% (95% CI: 97.83-100) and a specificity of 99.87% (95% CI: 99.55-99.98). More importantly, the assay supports a breakthrough sample pooling method, which makes possible parallel screening of up to 96 samples in one real-time PCR well without loss of sensitivity. As a result, up to 8,820 individual pre-amplified samples could be screened for SARS-CoV-2 within each 96-well plate of realtime PCR using the pooled testing procedure. CONCLUSION: The novel semi-nested RT-PCR assay provides a solution for highly multiplex (7-plex) detection of SARS-CoV-2 and enables 96-sample pooled detection for increase of testing capacity. .


Assuntos
COVID-19 , SARS-CoV-2 , Inteligência Artificial , COVID-19/diagnóstico , Humanos , Pandemias , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , SARS-CoV-2/genética , Sensibilidade e Especificidade
19.
Front Microbiol ; 13: 846677, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35432243

RESUMO

The halophilic γ-proteobacterium Halomonas elongata DSM 2581 T thrives at salt concentrations well above 10 % NaCl (1.7 M NaCl). A well-known osmoregulatory mechanism is the accumulation of the compatible solute ectoine within the cell in response to osmotic stress. While ectoine accumulation is central to osmoregulation and promotes resistance to high salinity in halophilic bacteria, ectoine has this effect only to a much lesser extent in non-halophiles. We carried out transcriptome analysis of H. elongata grown on two different carbon sources (acetate or glucose), and low (0.17 M NaCl), medium (1 M), and high salinity (2 M) to identify additional mechanisms for adaptation to high saline environments. To avoid a methodological bias, the transcripts were evaluated by applying two methods, DESeq2 and Transcripts Per Million (TPM). The differentially transcribed genes in response to the available carbon sources and salt stress were then compared to the transcriptome profile of Chromohalobacter salexigens, a closely related moderate halophilic bacterium. Transcriptome profiling supports the notion that glucose is degraded via the cytoplasmic Entner-Doudoroff pathway, whereas the Embden-Meyerhoff-Parnas pathway is employed for gluconeogenesis. The machinery of oxidative phosphorylation in H. elongata and C. salexigens differs greatly from that of non-halophilic organisms, and electron flow can occur from quinone to oxygen along four alternative routes. Two of these pathways via cytochrome bo' and cytochrome bd quinol oxidases seem to be upregulated in salt stressed cells. Among the most highly regulated genes in H. elongata and C. salexigens are those encoding chemotaxis and motility proteins, with genes for chemotaxis and flagellar assembly severely downregulated at low salt concentrations. We also compared transcripts at low and high-salt stress (low growth rate) with transcripts at optimal salt concentration and found that the majority of regulated genes were down-regulated in stressed cells, including many genes involved in carbohydrate metabolism, while ribosome synthesis was up-regulated, which is in contrast to what is known from non-halophiles at slow growth. Finally, comparing the acidity of the cytoplasmic proteomes of non-halophiles, extreme halophiles and moderate halophiles suggests adaptation to an increased cytoplasmic ion concentration of H. elongata. Taken together, these results lead us to propose a model for salt tolerance in H. elongata where ion accumulation plays a greater role in salt tolerance than previously assumed.

20.
Allergy ; 77(8): 2534-2548, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35266148

RESUMO

BACKGROUND: The PALISADE study, an international, phase 3 trial of peanut oral immunotherapy (POIT) with AR101, resulted in desensitization in children and adolescents who were highly allergic to peanut. An improved understanding of the immune mechanism induced in response to food allergen immunotherapy would enable more informed and effective therapeutic strategies. Our main purpose was to examine the immunological changes in blood samples from a subset of peanut-allergic individuals undergoing oral desensitization immunotherapy with AR101. METHODS: Blood samples obtained as part of enrollment screening and at multiple time points during PALISADE study were used to assess basophil and CD4+ T-cell reactivity to peanut. RESULTS: The absence of clinical reactivity to the entry double-blinded placebo-controlled peanut challenge (DBPCFC) was accompanied by a significantly lower basophil sensitivity and T-cell reactivity to peanut compared with DBPCFC reactors. At baseline, peanut-reactive TH2A cells were observed in many but not all peanut-allergic patients and their level in peripheral blood correlates with T-cell reactivity to peanut and with serum peanut-specific IgE and IgG4 levels. POIT reshaped circulating peanut-reactive T-cell responses in a subset-dependent manner. Changes in basophil and T-cell responses to peanut closely paralleled clinical benefits to AR101 therapy and resemble responses in those with lower clinical sensitivity to peanut. However, no difference in peanut-reactive Treg cell frequency was observed between groups. CONCLUSION: Oral desensitization therapy with AR101 leads to decreased basophil sensitivity to peanut and reshapes peanut-reactive T effector cell responses supporting its potential as an immunomodulatory therapy.


Assuntos
Hipersensibilidade a Amendoim , Administração Oral , Adolescente , Alérgenos , Arachis , Criança , Dessensibilização Imunológica/métodos , Humanos , Imunidade , Hipersensibilidade a Amendoim/terapia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...