RESUMO
OBJECTIVE: To investigate the effects of repeated vaccination with ancestral SARS-CoV-2 (Wuhan-hu-1)-based inactivated, recombinant protein subunit or vector-based vaccines on the neutralizing antibody response to Omicron subvariants. METHODS: Individuals who received four-dose vaccinations with the Wuhan-hu-1 strain, individuals who were infected with the BA.5 variant alone without prior vaccination, and individuals who experienced a BA.5 breakthrough infection following receiving 2-4 doses of the Wuhan-hu-1 vaccine were enrolled. Neutralizing antibodies against D614G, BA.5, XBB.1.5, EG.5.1, and BA.2.86 were detected using a pseudovirus-based neutralization assay. Antigenic cartography was used to analyze cross-reactivity patterns among D614G, BA.5, XBB.1.5, EG.5.1, and BA.2.86 and sera from individuals. RESULTS: The highest neutralizing antibody titers against D614G were observed in individuals who only received four-dose vaccination and those who experienced BA.5 breakthrough infection, which was also significantly higher than the antibody titers against XBB.1.5, EG.5.1, and BA.2.86. In contrast, only BA.5 infection elicited comparable neutralizing antibody titers against the tested variants. While neutralizing antibody titers against D614G or BA.5 were similar across the cohorts, the neutralizing capacity of antibodies against XBB.1.5, EG.5.1, and BA.2.86 was significantly reduced. BA.5 breakthrough infection following heterologous booster induced significantly higher neutralizing antibody titers against the variants, particularly against XBB.1.5 and EG.5.1, than uninfected vaccinated individuals, only BA.5 infected individuals, or those with BA.5 breakthrough infection after primary vaccination. CONCLUSIONS: Our findings suggest that repeated vaccination with the Wuhan-hu-1 strain imprinted a neutralizing antibody response toward the Wuhan-hu-1 strain with limited effects on the antibody response to the Omicron subvariants.
RESUMO
As the first member of the family with sequence similarity 3 (FAM3), FAM3A promotes synthesis of ATP in mitochondria of hepatic cells and cells from other organs. Dysregulations of FAM3A are involved in the development of diabetes and nonalcoholic fatty liver disease (NAFLD). So far, the molecule mechanism under the physiological and pathological functions of FAM3A is largely unexplored. Here, we determined the crystal structure of FAM3A at high resolution of 1.38Å, complexed with an unknown-source compound which was characterized through metabolomics and confirmed as methacholine by thermal shift assay and surface plasmon resonance (SPR). Exploration for natural ligands of FAM3A was conducted through the same molecular interaction assays. The observed binding of acyl-L-carnitine molecules indicated FAM3A participating in fatty acid beta-oxidation. Knockdown and rescue assays coupled with fatty acid oxidation determination confirmed the role of FAM3A in beta-oxidation. This investigation reveals the molecular mechanism for the biological function of FAM3A and would provide basis for identifying drug target for treatment of diabetes and NAFLD.
RESUMO
Hydrogen sulfide (H2S) is a pervasive gaseous pollutant that emits the characteristic odor of rotten gas, even at low concentrations. It is generated during various industrial processes, including petroleum and natural gas refining, mining operations, wastewater treatment activities, and refuse disposal practices. According to statistics from the World Health Organization (WHO), over 70 occupations are exposed to H2S, rendering it a key monitoring factor in occupational disease detection. Although H2S has legitimate uses in the chemical, medical, and other fields, prolonged exposure to this gas can cause severe damage to the respiratory and central nervous systems, as well as other organs in the human body. Moreover, the substantial release of H2S into the environment can lead to significant pollution. This noxious substance has the potential to impair soil, water, and air quality, while disrupting the equilibrium of the surrounding ecosystems. Therefore, sulfide has become one of the most commonly measured substances for environmental monitoring worldwide. Achieving the stable enrichment and accurate detection of low-level H2S is of great significance. Common methods for detecting this gas include spectrophotometry, chemical analysis, gas chromatography, rapid field detection, and ion chromatography. Although these methods provide relatively reliable results, they suffer from limitations such as high detection cost, low recovery, lack of environmental friendliness, and imprecise quantification of low-concentration H2S. Furthermore, the sampling processes involved in these methods are complex and require specialized equipment and electrical devices. Additionally, approximately 20% of the sulfides in a sample are lost after 2 h in a conventional alkaline sodium hydroxide solution, causing difficulties in preservation and detection. In this study, an accurate, efficient, and cost-saving method based on ion chromatography-pulse amperometry was developed for H2S determination. A conventional IonPac AS7 (250 mm×4 mm) anion-exchange column was employed, and a new eluent based on sodium hydroxide and sodium oxalate was used to replace the original sodium hydroxide-sodium acetate eluent. The main factors influencing the separation and detection performance of the proposed method, including the pulse amperage detection potential parameters and integration time, as well as the type and content of additives in the stabilizing solution, were optimized. The results showed that the proposed method had a good linear relationship between 10 and 3000 µg/L, with correlation coefficients (r2) of up to 0.999. The limits of detection (S/N=3) and quantification (S/N=10) were 1.53 and 5.10 µg/L, respectively. The relative standard deviations (RSDs) of the peak area and retention time of sulfides were less than 0.2% (n=6). The new method exhibited excellent stability, with up to 90% reduction in reagent costs. Compared with conventional ion chromatography-pulse amperometry, this method is more suitable for detecting low concentrations of sulfides in actual samples. Sulfides in a 250 mmol/L sodium hydroxide-0.8% (mass fraction) ethylenediaminetetraacetic acid disodium salt solution were effectively maintained for over 10 h. The new stabilizer significantly improved the reliability of both large-scale and long-term detection. The recovery of the proposed method was investigated by combining the system with a badge-type passive sampler. This sampling method requires no power devices; it is inexpensive, simple to operate, and can realize long-term sampling without the need for skilled personnel. Moreover, it can overcome the influence of short-term changes in pollutant concentration. The sampling results have high reference value for large-scale intervention-less pollutant monitoring in ultraclean rooms, museum counters, and other places. The results demonstrated that the recovery of the proposed method was greater than 95% for the blank sample and 80% for the sample plus standard solution. Finally, the newly established method was applied to determine H2S levels in air samples collected via passive sampling at school garbage stations. The measured results did not exceed the national limit.
Assuntos
Poluentes Atmosféricos , Sulfeto de Hidrogênio , Sulfeto de Hidrogênio/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Cromatografia por Troca Iônica/métodosRESUMO
Urea is a simple organic compound that is widely used in both the industry and daily life. Compared with conventional methods, the preparation of urea by electrochemical synthesis is more environmentally friendly and sustainable. However, after the reaction, low amounts of urea and high concentrations of inorganic ions, including [Formula: see text] concentration was achieved without interference. Thus, the developed method can be applied for the detection of trace urea and other related ions in urea-containing electrolyte products.
RESUMO
We aimed to build a deep learning-based pathomics model to predict the early recurrence of non-muscle-infiltrating bladder cancer (NMIBC) in this work. A total of 147 patients from Xuzhou Central Hospital were enrolled as the training cohort, and 63 patients from Suqian Affiliated Hospital of Xuzhou Medical University were enrolled as the test cohort. Based on two consecutive phases of patch level prediction and WSI-level predictione, we built a pathomics model, with the initial model developed in the training cohort and subjected to transfer learning, and then the test cohort was validated for generalization. The features extracted from the visualization model were used for model interpretation. After migration learning, the area under the receiver operating characteristic curve for the deep learning-based pathomics model in the test cohort was 0.860 (95% CI 0.752-0.969), with good agreement between the migration training cohort and the test cohort in predicting recurrence, and the predicted values matched well with the observed values, with p values of 0.667766 and 0.140233 for the Hosmer-Lemeshow test, respectively. The good clinical application was observed using a decision curve analysis method. We developed a deep learning-based pathomics model showed promising performance in predicting recurrence within one year in NMIBC patients. Including 10 state prediction NMIBC recurrence group pathology features be visualized, which may be used to facilitate personalized management of NMIBC patients to avoid ineffective or unnecessary treatment for the benefit of patients.
Assuntos
Aprendizado Profundo , Recidiva Local de Neoplasia , Neoplasias não Músculo Invasivas da Bexiga , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Recidiva Local de Neoplasia/patologia , Neoplasias não Músculo Invasivas da Bexiga/patologia , Curva ROC , Medição de Risco/métodosRESUMO
In recent years, studies on the degradation of emerging organic contaminants by sulfate radical (SO4-·) based advanced oxidation processes (SR-AOPs) have triggered increasing attention. Metal-loaded biochar (Me-BC) can effectively prevent the agglomeration and leaching of transition metals, and its good physicochemical properties and abundant active sites induce outstanding in activating persulfate (PS) for pollutant degradation, which is of great significance in the field of advanced oxidation. In this paper, we reviewed the preparation method and stability of Me-BC, the effect of metal loading on the physicochemical properties of biochar, the pathways of pollutant degradation by Me-BC-activated PS (including free radical pathways: SO4-·, hydroxyl radical (·OH), superoxide radicals (O2-·); non-free radical pathways: singlet oxygen (1O2), direct electron transfer), and discussed the activation of different active sites (including metal ions, persistent free radicals, oxygen-containing functional groups, defective structures, etc.) in the SR-AOPs system. Finally, the prospect was presented for the current research progress of Me-BC in SR-AOPs technology.
Assuntos
Carvão Vegetal , Sulfatos , Poluentes Químicos da Água , Carvão Vegetal/química , Sulfatos/química , Poluentes Químicos da Água/química , Metais/química , OxirreduçãoRESUMO
Hot-carrier transistors are a class of devices that leverage the excess kinetic energy of carriers. Unlike regular transistors, which rely on steady-state carrier transport, hot-carrier transistors modulate carriers to high-energy states, resulting in enhanced device speed and functionality. These characteristics are essential for applications that demand rapid switching and high-frequency operations, such as advanced telecommunications and cutting-edge computing technologies1-5. However, the traditional mechanisms of hot-carrier generation are either carrier injection6-11 or acceleration12,13, which limit device performance in terms of power consumption and negative differential resistance14-17. Mixed-dimensional devices, which combine bulk and low-dimensional materials, can offer different mechanisms for hot-carrier generation by leveraging the diverse potential barriers formed by energy-band combinations18-21. Here we report a hot-emitter transistor based on double mixed-dimensional graphene/germanium Schottky junctions that uses stimulated emission of heated carriers to achieve a subthreshold swing lower than 1 millivolt per decade beyond the Boltzmann limit and a negative differential resistance with a peak-to-valley current ratio greater than 100 at room temperature. Multi-valued logic with a high inverter gain and reconfigurable logic states are further demonstrated. This work reports a multifunctional hot-emitter transistor with significant potential for low-power and negative-differential-resistance applications, marking a promising advancement for the post-Moore era.
Assuntos
Temperatura Alta , Transistores Eletrônicos , Grafite/químicaRESUMO
Hereditary leiomyomatosis and renal cell cancer (HLRCC) is a rare autosomal dominant syndrome caused by a germline mutation in the fumarate hydratase (FH) gene that manifests with cutaneous leiomyomas, uterine fibroids, and renal cell cancer (RCC). Patients with HLRCC-associated RCC (HLRCC-RCC) have aggressive clinical courses, but there is no standardized therapy for advanced HLRCC-RCC. In this study, we described a case of aggressive HLRCC in a 33-year-old female who exhibited a novel heterozygous germline insertion mutation in exon 8 of the FH gene (c.1126 C > T; p.Q376*). The patient underwent laparoscopic resection of the right kidney, but metastases appeared within 3 months after surgery. Histological staining of the resected tumor revealed high expression levels of programmed cell death-ligand 1 (PD-L1). Therefore, the patient was treated with immunotherapy. The patient achieved a partial response to immunotherapy, and the treatment of metastatic lesions has continued to improve. A thorough literature review pinpointed 76 historical cases of HLRCC-RCC that had undergone immunotherapy. From this pool, 46 patients were selected for this study to scrutinize the association between mutations in the FH gene and the effectiveness of immunotherapy. Our results indicate that immunotherapy could significantly improve the overall survival (OS) of patients with HLRCC-RCC. However, no influence of different mutations in the FH germline gene on the therapeutic efficacy of immunotherapy was observed. Therefore, our study suggested that immunotherapy was an effective therapeutic option for patients with HLRCC regardless of the type of FH germline mutation.
Assuntos
Fumarato Hidratase , Imunoterapia , Leiomiomatose , Síndromes Neoplásicas Hereditárias , Neoplasias Cutâneas , Neoplasias Uterinas , Humanos , Feminino , Leiomiomatose/genética , Leiomiomatose/patologia , Leiomiomatose/terapia , Fumarato Hidratase/genética , Adulto , Síndromes Neoplásicas Hereditárias/genética , Síndromes Neoplásicas Hereditárias/terapia , Síndromes Neoplásicas Hereditárias/complicações , Síndromes Neoplásicas Hereditárias/patologia , Neoplasias Uterinas/genética , Neoplasias Uterinas/patologia , Neoplasias Uterinas/terapia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/terapia , Mutação em Linhagem Germinativa , Neoplasias Renais/genética , Neoplasias Renais/patologia , Neoplasias Renais/terapia , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/terapiaRESUMO
We conducted a longitudinal cohort study of SARS-CoV-2 and influenza rates in childcare centers and schools in Wuxi, China, collecting 1,760 environmental samples and 9,214 throat swabs from 593 students (regardless of symptoms) in weekly collections during February-June 2023. We estimated a cumulative infection rate of 124.8 (74 episodes)/1,000 persons for SARS-CoV-2 and 128.2 (76 episodes)/1,000 persons for influenza. The highest SARS-CoV-2 infection rate was in persons 18 years of age, and for influenza, in children 4 years of age. The asymptomatic proportion of SARS-CoV-2 was 59.6% and 66.7% for influenza; SARS-CoV-2 symptomatic proportion was lower in 16-18-year-olds than in 4-6-year-olds. Only samples from frequently touched surface tested positive for SARS-CoV-2 (4/1,052) and influenza (1/1,052). We found asynchronous circulation patterns of SARS-CoV-2 and influenza, similar to trends in national sentinel surveillance. The results support vaccination among pediatric populations and other interventions, such as environmental disinfection in educational settings.
Assuntos
COVID-19 , Influenza Humana , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , COVID-19/virologia , Criança , Influenza Humana/epidemiologia , Influenza Humana/virologia , Adolescente , China/epidemiologia , Pré-Escolar , Masculino , Feminino , Estudos Longitudinais , LactenteRESUMO
OBJECTIVE: To investigate the clinical effect of magnetic stimulation combined with moxibustion on mild to moderate overactive bladder (OAB) and sexual function in women. METHODS: We enrolled 80 female patients with mild to moderate OAB in this study and equally randomized them into a control and an experimental group, the former treated by magnetic stimulation and the latter by magnetic stimulation combined with moxibustion, both for 8 weeks. We obtained from the patients their OAB syndrome scores (OABSS), 72-hour urination diary (72-h UD) scores, International Consultation on Incontinence Questionnaire ï¼ Overactive Bladder (ICIQ-OAB) scores and female sexual function indexes (FSFI), and compared them between the two groups before and after intervention. RESULTS: A total of 77 patients completed the study, 37 in the control and 40 in the experimental group. There were no statistically significant differences in the baseline data between the two groups (P > 0.05). Compared with the baseline, the experimental group showed significant improvement after treatment in the OABSS (7.54±1.12 vs 4.46±0.96), 72-h urine volume (ï¼»126.40±46.04ï¼½ vs ï¼»216.63±38.26ï¼½ ml), urination frequency (15.55±3.21 vs 8.03±1.40), ICIQ-OAB score (10.25±1.15 vs 6.32±1.07) and FSFI (20.00±12.40 vs 33.30±21.00) (all P < 0.05), even more significantly than in the control group (OABSS: 4.46±0.96 vs 5.59±0.90; 72-h urine volume: ï¼»216.63±38.26ï¼½ vs ï¼»173.41±15.55ï¼½ ml; urination frequency: 8.03±1.40 vs 9.90±1.49; ICIQ-OAB score: 6.32±1.07 vs 7.89±0.77; FSFI: 33.30±21.00 vs 30.40±10.40) (all P < 0.01). CONCLUSION: Magnetic stimulation combined with moxibustion can improve the symptoms of mild to moderate overactive bladder and improve sexual function in females.
Assuntos
Magnetoterapia , Moxibustão , Bexiga Urinária Hiperativa , Humanos , Feminino , Bexiga Urinária Hiperativa/terapia , Moxibustão/métodos , Magnetoterapia/métodos , Pessoa de Meia-Idade , Adulto , Resultado do TratamentoRESUMO
In this study, Listeria monocytogenes from minced pork was evaluated for changes in resistance to thermal treatment and gastric fluid following environmental stresses during food processing. Bacteria were exposed to cold stress, followed by successive exposures to different stressors (lactic acid (LA), NaCl, or Nisin), followed by thermal treatments, and finally, their gastrointestinal tolerance was determined. Adaptation to NaCl stress reduced the tolerance of L. monocytogenes to subsequent LA and Nisin stress. Adaptation to LA stress increased bacterial survival in NaCl and Nisin-stressed environments. Bacteria adapted to Nisin stress showed no change in tolerance to subsequent stress conditions. In addition, treatment with NaCl and LA enhanced the thermal tolerance of L. monocytogenes, but treatment with Nisin decreased the thermal tolerance of the bacteria. Almost all of the sequential stresses reduced the effect of a single stress on bacterial thermal tolerance. The addition of LA and Nisin as a second step of stress reduced the tolerance of L. monocytogenes to gastric fluid, whereas the addition of NaCl enhanced its tolerance. The results of this study are expected to inform processing conditions and sequences for meat preservation and processing and reduce uncertainty in risk assessment of foodborne pathogens due to stress adaptation.
Assuntos
Manipulação de Alimentos , Microbiologia de Alimentos , Listeria monocytogenes , Produtos da Carne , Nisina , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/fisiologia , Nisina/farmacologia , Produtos da Carne/microbiologia , Animais , Manipulação de Alimentos/métodos , Temperatura Alta , Cloreto de Sódio , Suínos , Estresse Fisiológico , Conservação de Alimentos/métodos , Adaptação FisiológicaRESUMO
The effective method for trypsin purification should be established because trypsin has important economic value. In this work, a novel and simple strategy was proposed for fabricating micron-sized magnetic Fe3O4@agarose-benzamidine beads (MABB) with benzamidine as a ligand, which can efficiently and selectively capture trypsin. The micro-sized MABB, with clear spherical core-shell structure and average particle size of 6.6 µm, showed excellent suspension ability and magnetic responsiveness in aqueous solution. The adsorption capacity and selectivity of MABB towards target trypsin were significantly better than those of non-target lysozyme. According to the Langmuir equation, the maximum adsorption capacity of MABB for trypsin was 1946 mg g-1 at 25 °C, and the adsorption should be a physical sorption process. Furthermore, the initial adsorption rate and half equilibrium time of MABB toward trypsin were 787.4 mg g-1 min-1 and 0.71 min, respectively. To prove the practicability, MABB-based magnetic solid-phase extraction (MSPE) was proposed, and the related parameters were optimized in detail to improve the purification efficiency. With Tris-HCl buffer (50 mM, 10 mM CaCl2, pH 8.0) as extraction buffer, Tris-HCl buffer (50 mM, 100 mM CaCl2, pH 8.0) as rinsing buffer, acidic eluent (0.01 M HCl, 0.5 M NaCl, pH 2.0) as eluent buffer and alkaline buffer (1 M Tris-HCl buffer, pH 10.0) as neutralization solution, the MABB-based MSPE was successfully used for trypsin purification from the viscera of grass carp (Ctenopharyngodon idella). The molecular weight of purified trypsin was determined as approximate 23 kDa through sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The purified trypsin was highly active from 30 °C to 60 °C, with an optimum temperature of 50 °C, and was tolerant to pH variation, exhibiting 85 % of maximum enzyme activity from pH 7.0 to 10.0. The results demonstrated that the proposed MABB-based MSPE could effectively purify trypsin and ensure the biological activity of purified trypsin. Therefore, we believe that the novel MABB could be applicable for efficient purification of trypsin from complex biological systems.
RESUMO
Purpose: Although brain metastasis (BM) from gastric cancer (GC) is relatively uncommon, its incidence has been increasing owing to advancements in treatment modalities. Unfortunately, patients diagnosed with BM from gastric cancer have poor life expectancy. Our study aims to establish a predictive model for brain metastasis in advanced gastric cancer patients, thus enabling the timely diagnosis of brain metastasis. Patients and Methods: The clinicopathological features of a cohort which included 40 GC patients with brain metastasis, 32 of whom from the First Affiliated Hospital of Nanchang University, 2 from Gaoxin Branch of the First Affiliated Hospital of Nanchang University, remaining 6 from Anyang District Hospital, and 80 non-metastatic advanced GC patients from the First Affiliated Hospital of Nanchang University between 2018 and 2022. Data were retrospectively analyzed. Results: Age, tumor size, differentiation, lymph node grade, tumor location, Lauren classification, liver metastasis, carbohydrate antigen 199 (CA199), lactate dehydrogenase (LDH), and human epidermal growth factor receptor 2 (Her-2) were associated with BM. A nomogram integrated with nine risk factors (tumor size, differentiation, lymph node grade, tumor location, Lauren classification, liver metastasis, CA-199, LDH, and Her-2) showed good performance (Area Under Curve 0.95, 95% CI: 0.91-0.98). Conclusion: We developed and validated a nomogram that achieved individualized prediction of the possibility of BM from GC. This model enables personalized imaging review schedules for timely brain metastasis detection in advanced gastric cancer patients.
RESUMO
Although cytochrome P450 enzymes are the most versatile biocatalysts in nature, there is insufficient comprehension of the molecular mechanism underlying their functional innovation process. Here, by combining ancestral sequence reconstruction, reverse mutation assay, and progressive forward accumulation, we identified 5 founder residues in the catalytic pocket of flavone 6-hydroxylase (F6H) and proposed a "3-point fixation" model to elucidate the functional innovation mechanisms of P450s in nature. According to this design principle of catalytic pocket, we further developed a de novo diffusion model (P450Diffusion) to generate artificial P450s. Ultimately, among the 17 non-natural P450s we generated, 10 designs exhibited significant F6H activity and 6 exhibited a 1.3- to 3.5-fold increase in catalytic capacity compared to the natural CYP706X1. This work not only explores the design principle of catalytic pockets of P450s, but also provides an insight into the artificial design of P450 enzymes with desired functions.
RESUMO
A signal amplification electrochemical biosensor chip was developed to integrate loop-mediated isothermal amplification (LAMP) based on in situ nucleic acid amplification and methyl blue (MB) serving as the hybridization redox indicator for sensitive and selective foodborne pathogen detection without a washing step. The electrochemical biosensor chip was designed by a screen-printed carbon electrode modified with gold nanoparticles (Au NPs) and covered with polydimethylsiloxane membrane to form a microcell. The primers of the target were immobilized on the Au NPs by covalent attachment for in situ amplification. The electroactive MB was used as the electrochemical signal reporter and embedded into the double-stranded DNA (dsDNA) amplicons generated by LAMP. Differential pulse voltammetry was introduced to survey the dsDNA hybridization with MB, which differentiates the specifically electrode-unbound and -bound labels without a washing step. Pyrene as the back-filling agent can further improve response signaling by reducing non-specific adsorption. This method is operationally simple, specific, and effective. The biosensor showed a detection linear range of 102-107 CFU mL-1 with the limit of detection of 17.7 CFU mL-1 within 40 min. This method showed promise for on-site testing of foodborne pathogens and could be integrated into an all-in-one device.
Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Microbiologia de Alimentos , Ouro , Nanopartículas Metálicas , Técnicas de Amplificação de Ácido Nucleico , Técnicas de Amplificação de Ácido Nucleico/métodos , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais/métodos , Ouro/química , Nanopartículas Metálicas/química , Limite de Detecção , Eletrodos , DNA Bacteriano/análise , DNA Bacteriano/genética , Hibridização de Ácido NucleicoRESUMO
Bacillus cereus causes food poisoning by producing toxins that cause diarrhea and vomiting and, in severe cases, endocarditis, meningitis, and other diseases. It also tends to form biofilms and spores that lead to contamination of the food production environment. Citral is a potent natural antibacterial agent, but its antibacterial activity against B. cereus has not been extensively studied. In this study, we first determined the minimum inhibitory concentrations and minimum bactericidal concentrations, growth curves, killing effect in different media, membrane potential, intracellular adenosine triphosphate (ATP), reactive oxygen species levels, and morphology of vegetative cells, followed by germination rate, morphology, germination state of spores, and finally biofilm clearance effect. The results showed that the minimum inhibitory concentrations and minimum bactericidal concentrations of citral against bacteria ranged from 100 to 800 µg/mL. The lag phase of bacteria was effectively prolonged by citral, and the growth rate of bacteria was slowed down. Bacteria in Luria-Bertani broth were reduced to below the detection limit by citral at 800 µg/mL within 0.5 h. Bacteria in rice were reduced to 3 log CFU/g by citral at 4000 µg/mL within 0.5 h. After treatment with citral, intracellular ATP concentration was reduced, membrane potential was altered, intracellular reactive oxygen species concentration was increased, and normal cell morphology was altered. After treatment with citral at 400 µg/mL, spore germination rate was reduced to 16.71%, spore morphology was affected, and spore germination state was altered. It also had a good effect on biofilm removal. The present study showed that citral had good bacteriostatic activity against B. cereus vegetative cells and its spores and also had a good clearance effect on its biofilm. Citral has the potential to be used as a bacteriostatic substance for the control of B. cereus in food industry production.
Assuntos
Monoterpenos Acíclicos , Bacillus cereus , Biofilmes , Monoterpenos Acíclicos/farmacologia , Anti-Infecciosos/farmacologia , Bacillus cereus/efeitos dos fármacos , Bacillus cereus/crescimento & desenvolvimento , Bacillus cereus/ultraestrutura , Esporos Bacterianos/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Oryza/microbiologia , Potenciais da Membrana/efeitos dos fármacos , Espaço Intracelular/enzimologia , Trifosfato de Adenosina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Microscopia Eletrônica de Varredura , Microbiologia de AlimentosRESUMO
Vibrio parahaemolyticus (V. parahaemolyticus) is a major foodborne pathogen, which can cause serious foodborne illnesses like diarrhoea. Rapid on-site detection of foodborne pathogens is an ideal way to respond to foodborne illnesses. Herein, we provide an electrochemical sensor for rapid on-site detection. This sensor utilized a pH-sensitive metal-oxide material for the concurrent isothermal amplification and label-free detection of nucleic acids. Based on a pH-sensitive hydrated iridium oxide oxyhydroxide film (HIROF), the electrode transforms the hydrogen ion compound generated during nucleic acid amplification into potential, so as to achieve a real-time detection. The results can be transmitted to a smartphone via Bluetooth. Moreover, HIROF was applied in nucleic acid device detection, with a super-Nernst sensitivity of 77.6 mV/pH in the pH range of 6.0-8.5, and the sensitivity showed the best results so far. Detection of V. parahaemolyticus by this novel method showed a detection limit of 1.0 × 103 CFU/mL, while the time consumption was only 30 min, outperforming real-time fluorescence loop-mediated isothermal amplification (LAMP). Therefore, the characteristics of compact, portable, and fast make the sensor more widely used in on-site detection.
Assuntos
Técnicas Eletroquímicas , Irídio , Vibrio parahaemolyticus , Vibrio parahaemolyticus/isolamento & purificação , Vibrio parahaemolyticus/genética , Concentração de Íons de Hidrogênio , Técnicas Eletroquímicas/métodos , Irídio/química , Técnicas de Amplificação de Ácido Nucleico/métodos , Técnicas Biossensoriais/métodos , Limite de Detecção , EletrodosRESUMO
The emergence of novel Omicron subvariants has raised concerns regarding the efficacy of immunity induced by prior Omicron subvariants breakthrough infection (BTI) or reinfection against current circulating Omicron subvariants. Here, we prospectively investigated the durability of antibody and T cell responses in individuals post Omicron BA.2.2 BTI, with or without subsequent Omicron BA.5 reinfection. Our findings reveal that the emerging Omicron subvariants, including CH.1.1, XBB, and JN.1, exhibit extensive immune evasion induced by previous infections. Notably, the level of IgG and neutralizing antibodies were found to correlate with subsequent Omicron BA.5 reinfection. Fortunately, T cell responses recognizing both Omicron BA.2 and CH.1.1 peptides were observed. Furthermore, Omicron BA.5 reinfection may alleviate immune imprinting induced by WT-vaccination, bolster virus-specific ICS+ T cell responses, and promote the phenotypic differentiation of virus-specific memory CD8+ T cells. Antigen-updated or T cell-conserved vaccines are needed to control the transmission of diverse emerging SARS-CoV-2 variants.
RESUMO
Objective: This study aimed to explore whether famine exposure during early life are associated with a high risk of Type 2 Diabetes Mellitus (T2DM) in adulthood and the role of socioeconomic status (SES) on this effect. Materials and methods: We conducted a secondary data analysis based on data from a cross-sectional survey, collected 3,355 participants born between January 1, 1941 and December 31, 1966. Participants were categorized into four groups based on their date of birth, unexposed (individuals born in 1963-1966), infant exposed (individuals born in 1959-1962), childhood exposed (individuals born in 1949-1958), and adolescent exposed (born in 1941-1948). The association of famine exposure with T2DM risk in adults and conducted separately in plain area and mountain area was assessed using logistics regression model. Result: 22.35% of participants were diagnosed with T2DM, of which 43.47% were from the childhood famine-exposed group, representing the highest proportion among all subgroups (p < 0.001). Participants exposed to famine during childhood and adolescence from the lower SES mountain areas showed a significantly higher prevalence of T2DM in adulthood than those from the plain areas (p < 0.001). The adolescence stage exposed famine will increase the risk of T2DM in the mountain area (OR 2.46, 95% CI 1.61, 3.77). Conclusion: No strong evidence demonstrates that exposure to famine during the early life stage increases the risk of developing T2DM in adulthood. However, populations with lower SES are likely to be exposed to more risk factors for T2DM.
RESUMO
Cytochrome P450 2D6 (CYP2D6) is a key enzyme that mediates the metabolism of various drugs and endogenous substances in humans. However, its biological role in drug-drug interactions especially mechanism-based inactivation (MBI), and various diseases remains poorly understood, owing to the lack of molecular tools suitable for selectively monitoring CYP2D6 in complex biological systems. Herein, using a tailored molecular strategy, we developed a fluorescent probe BDPM for CYP2D6. BDPM exhibits excellent specificity and imaging capability for CYP2D6, making it suitable for the real-time monitoring of endogenous CYP2D6 activity in living bio-samples. Therefore, our tailored strategy proved useful for constructing the highly selective and enzyme-activated fluorescent probes. BDPM as a molecular tool to explore the critical roles of CYP2D6 in the pathogenesis of diseases, high-throughput screening of inhibitors and intensive investigation of CYP2D6-induced MBI in natural systems.