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Mucosal-associated invariant T (MAIT) cells are a subset of unconventional T cells that recognize small molecule metabolites presented by major histocompatibility complex class I related protein 1 (MR1), via an αß T cell receptor (TCR). MAIT TCRs feature an essentially invariant TCR α-chain, which is highly conserved between mammals. Similarly, MR1 is the most highly conserved major histocompatibility complex-I-like molecule. This extreme conservation, including the mode of interaction between the MAIT TCR and MR1, has been shown to allow for species-mismatched reactivities unique in T cell biology, thereby allowing the use of selected species-mismatched MR1-antigen (MR1-Ag) tetramers in comparative immunology studies. However, the pattern of cross-reactivity of species-mismatched MR1-Ag tetramers in identifying MAIT cells in diverse species has not been formally assessed. We developed novel cattle and pig MR1-Ag tetramers and utilized these alongside previously developed human, mouse, and pig-tailed macaque MR1-Ag tetramers to characterize cross-species tetramer reactivities. MR1-Ag tetramers from each species identified T cell populations in distantly related species with specificity that was comparable to species-matched MR1-Ag tetramers. However, there were subtle differences in staining characteristics with practical implications for the accurate identification of MAIT cells. Pig MR1 is sufficiently conserved across species that pig MR1-Ag tetramers identified MAIT cells from the other species. However, MAIT cells in pigs were at the limits of phenotypic detection. In the absence of sheep MR1-Ag tetramers, a MAIT cell population in sheep blood was identified phenotypically, utilizing species-mismatched MR1-Ag tetramers. Collectively, our results validate the use and define the limitations of species-mismatched MR1-Ag tetramers in comparative immunology studies.
Assuntos
Antígenos de Histocompatibilidade Classe I , Antígenos de Histocompatibilidade Menor , Células T Invariantes Associadas à Mucosa , Especificidade da Espécie , Animais , Células T Invariantes Associadas à Mucosa/imunologia , Células T Invariantes Associadas à Mucosa/metabolismo , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Camundongos , Bovinos , Antígenos de Histocompatibilidade Menor/metabolismo , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/imunologia , Antígenos de Histocompatibilidade Menor/química , Suínos , Macaca , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Receptores de Antígenos de Linfócitos T alfa-beta/genéticaRESUMO
Powdery mildew (PM) is one of the most serious fungal diseases affecting cucumbers (Cucumis sativus L.). The mechanism of PM resistance in cucumber is intricate and remains fragmentary as it is controlled by several genes. In this study, we detected the major-effect Quantitative Trait Locus (QTL), PM5.2, involved in PM resistance by QTL mapping. Through fine mapping, the dominant PM resistance gene, CsPM5.2, was cloned and its function was confirmed by transgenic complementation and natural variation identification. In cultivar 9930, a dysfunctional CsPM5.2 mutant resulted from a single nucleotide polymorphism in the coding region and endowed susceptibility to PM. CsPM5.2 encodes a phosphate transporter-like protein PHO1; H3. The expression of CsPM5.2 is ubiquitous and induced by the PM pathogen. In cucumber, both CsPM5.2 and Cspm5.1 (Csmlo1) are required for PM resistance. Transcriptome analysis suggested that the salicylic acid (SA) pathway may play an important role in CsPM5.2-mediated PM resistance. Our findings help parse the mechanisms of PM resistance and provide strategies for breeding PM-resistant cucumber cultivars.
Assuntos
Ascomicetos , Cucumis sativus , Cucumis sativus/genética , Fosfatos , Ascomicetos/genética , Melhoramento Vegetal , Mapeamento Cromossômico , Resistência à Doença/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologiaRESUMO
New neurones are generated throughout life in the mammalian brain in a process known as adult hippocampal neurogenesis (AHN). Since this phenomenon grants a high degree of neuroplasticity influencing learning and memory, identifying factors that regulate AHN may be important for ameliorating age-related cognitive decline. Calorie restriction (CR) has been shown to enhance AHN and improve memory, mediated by the stomach hormone, ghrelin. Intermittent fasting (IF), a dietary strategy offering more flexibility than conventional CR, has also been shown to promote aspects of AHN. The 5:2 diet is a popular form of IF; however, its effects on AHN are not well characterised. To address this, we quantified AHN in adolescent and adult wild-type and ghrelin-receptor-deficient mice following 6 weeks on a 5:2 diet. We report an age-related decline in neurogenic processes. However, the 5:2 diet does not increase AHN nor enhance memory performance, suggesting that this specific form of IF is ineffective in promoting brain plasticity to support learning.
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Grelina , Memória Espacial , Camundongos , Animais , Dieta , Neurogênese , Hipocampo , MamíferosRESUMO
Visual hallucinations can increase the burden of disease for both patients with Parkinson's disease and their caregivers. Multiple neurotransmitters have been implicated in the neuropathology of visual hallucinations, which provide targets for treatment and prevention. In this study, we assessed the association between cholinergic denervation and visual hallucinations in Parkinson's disease in vivo, using PET imaging of the cholinergic system. A total of 38 patients with Parkinson's disease participated in this study. A group of 10 healthy subjects, matched for age, sex and education, was included for comparison. None of the participants used cholinergic drugs. Thirteen patients who had experienced visual hallucinations in the past month (VH+) were compared with 20 patients who had never experienced visual hallucinations in their lives (VH-). Cholinergic system integrity was assessed with PET imaging using 18F-fluoroethoxybenzovesamicol as the tracer. We assessed the differences in tracer uptake between groups by cluster-based analysis and by analysis of predefined regions of interest consisting of the ventral visual stream, the dorsal attentional network, the ventral attentional network and the lateral geniculate nucleus and mediodorsal nucleus of the thalamus. The Parkinson's disease group (n = 38) showed an extensive pattern of decreased tracer uptake throughout the brain compared with the controls (n = 10). Within the Parkinson's disease group, the VH+ group (n = 13) showed a cluster of decreased tracer uptake compared with the VH- group (n = 20), which covered most of the left ventral visual stream and extended towards superior temporal areas. These results were mirrored in the regions of interest-based analysis, in which the VH+ group showed the strongest deficits in the left inferior temporal gyrus and the left superior temporal gyrus compared with the VH- group. Visual hallucinations in Parkinson's disease are associated with a marked cholinergic deficiency in the left ventral visual stream and the left superior temporal lobe, in addition to an extensive global cholinergic denervation in the general Parkinson's disease population.
Assuntos
Alucinações , Doença de Parkinson , Tomografia por Emissão de Pósitrons , Humanos , Doença de Parkinson/complicações , Alucinações/etiologia , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagem , PiperidinasRESUMO
In this issue (J Bacteriol. 206: e0014024, https://doi.org/10.1128/jb.00140-24), Ridone and Baker describe hybrids between two 5:2 heteroheptameric ion-powered motors. Chimeras were constructed between stator units of a bacterial flagellum and ExbBD of the Ton outer-membrane transport system. Only one of the 14 hybrids supported swimming in Escherichia coli. Three additional residue changes at sites distant from the hybrid region enhanced motility. This work suggests that flagellar stator units and ExbBD share an ancestor that diverged during evolution to perform different tasks.
Assuntos
Escherichia coli , Flagelos , Escherichia coli/genética , Escherichia coli/metabolismo , Flagelos/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/química , Proteínas Motores Moleculares/metabolismo , Proteínas Motores Moleculares/genética , Proteínas Motores Moleculares/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/químicaRESUMO
Anastasis is a phenomenon observed in cancer cells, where cells that have initiated apoptosis are able to recover and survive. This molecular event is increasingly recognized as a potential contributor to cancer metastasis, facilitating the survival and migration of tumor cells. Nevertheless, the identification of a specific surface marker for detecting cancer cells in anastasis remained elusive. Here we report our observation that the cell surface expression of CD24 is preferentially enriched in a non-adherent FSClowSSChigh melanoma subpopulation, which is generally considered a non-viable population in cultivated melanoma cell lines. More than 90% of non-adherent FSClowSSChighCD24+ve metastatic melanoma cells exhibited bonafide features of apoptosis on the cell surface and in the nucleus, marking apoptotic or seemingly apoptotic subpopulations of the in vitro cultivated metastatic melanoma cell lines. Unexpectedly, however, the CD24+ve subpopulation, despite being apoptotic, showed evidence of metabolic activity and exhibited proliferative capacities, including anchorage-independent growth, when inoculated in soft agarose growth medium. These findings indicate that apoptotic FSClowSSChighCD24+ve melanoma subpopulations are capable of reversing the progression of apoptosis. We report CD24 as the first novel cell surface marker for anastasis in melanoma cells.
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The Coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains a global threat, exacerbated by the emergence of viral variants. Two variants of SARS-CoV-2, Omicron BA.2.75 and BA.5, led to global infection peaks between May 2022 and May 2023, yet their precise characteristics in pathogenesis are not well understood. In this study, we compared these two Omicron sublineages with the previously dominant Delta variant using a human angiotensin-converting enzyme 2 knock-in mouse model. As expected, Delta exhibited higher viral replication in the lung and brain than both Omicron sublineages which induced less severe lung damage and immune activation. In contrast, the Omicron variants especially BA.5.2 showed a propensity for cellular proliferation and developmental pathways. Both Delta and BA.5.2 variants, but not BA.2.75, led to decreased pulmonary lymphocytes, indicating differential adaptive immune response. Neuroinvasiveness was shared with all strains, accompanied by vascular abnormalities, synaptic injury, and loss of astrocytes. However, Immunostaining assays and transcriptomic analysis showed that BA.5.2 displayed stronger immune suppression and neurodegeneration, while BA.2.75 exhibited more similar characteristics to Delta in the cortex. Such differentially infectious features could be partially attributed to the weakened interaction between Omicron Spike protein and host proteomes decoded via co-immunoprecipitation followed by mass spectrometry in neuronal cells. Our present study supports attenuated replication and pathogenicity of Omicron variants but also highlights their newly infectious characteristics in the lung and brain, especially with BA.5.2 demonstrating enhanced immune evasion and neural damage that could exacerbate neurological sequelae.
Assuntos
COVID-19 , Doenças Transmissíveis , Doenças do Sistema Nervoso , Animais , Camundongos , Humanos , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genéticaRESUMO
The 5-2-1 criteria are intended to help general neurologists identify patients with advanced Parkinson's disease who may benefit from treatment optimisation, such as with a device-aided therapy. Although the 5-2-1 criteria claim to address an unmet need, we urge readers to cautiously interpret the results of this validation study.
Assuntos
Doença de Parkinson , Doença de Parkinson/diagnóstico , HumanosRESUMO
The 5-2-1 criteria was developed to facilitate the identification and referral of patients with Parkinson's Disease (PD) inadequately controlled by oral medications. The criterion was not developed to screen patients with PD for device-aided therapy eligibility. The robust design and validation of the 5-2-1 criteria minimizes over or inappropriate referrals, and supports physicians in the timely identification of patients with PD who may warrant further evaluation for treatment optimization. This response letter clarifies concerns raised by Moes et al.
Assuntos
Doença de Parkinson , Doença de Parkinson/diagnóstico , Humanos , Antiparkinsonianos/uso terapêuticoRESUMO
This non-randomized controlled trial aimed to compare the effect of the 5:2 diet on insulin levels as a primary outcome and markers of insulin secretion (connecting peptide (C-peptide) and insulin-like growth factor binding protein-1 (IGFBP-1)) and sensitivity (Homeostatic Model Assessment for Insulin Resistance (HOMA-IR)), as well as body composition as secondary outcomes in overweight/obese individuals with and without type 2 diabetes (T2D). Ninety-seven participants (62% women), 35 with T2D and 62 BMI- and waist-matched controls without T2D, followed the 5:2 diet (two days per week of fasting) for six months with a 12-month follow-up. At six months, there was no loss to follow-up in the T2D group, whereas four controls discontinued this study. Overall, 82% attended the 12-month follow-up. After the intervention, insulin levels decreased in the control group and glucose decreased in the T2D group, while C-peptide, HOMA-IR, waist circumference, BMI, trunk, and total fat% decreased in both groups. Furthermore, low IGFBP-1, indicating hyperinsulinemia, improved in the T2D group. The changes in fasting glucose and waist measurement were significantly more improved in the T2D group than in the controls. Persistent positive effects were observed at the 12-month follow-up. The 5:2 diet for six months was feasible and efficient to reduce markers of insulin secretion and resistance and therefore holds promise as management of overweight/obesity in subjects with and without T2D.
Assuntos
Biomarcadores , Diabetes Mellitus Tipo 2 , Resistência à Insulina , Secreção de Insulina , Insulina , Humanos , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/dietoterapia , Feminino , Masculino , Pessoa de Meia-Idade , Insulina/metabolismo , Insulina/sangue , Peptídeo C/sangue , Peptídeo C/metabolismo , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Adulto , Glicemia/metabolismo , Dieta , Índice de Massa Corporal , Obesidade/metabolismo , Obesidade/dietoterapia , Composição Corporal , Sobrepeso/metabolismo , Sobrepeso/dietoterapiaRESUMO
The genome-the source of life and platform of evolution-is continuously exposed to harmful factors, both extra- and intra-cellular. Their activity causes different types of DNA damage, with approximately 80 different types of lesions having been identified so far. In this paper, the influence of a clustered DNA damage site containing imidazolone (Iz) or oxazolone (Oz) and 7,8-dihydro-8-oxo-2'-deoxyguanosine (OXOdG) on the charge transfer through the double helix as well as their electronic properties were investigated. To this end, the structures of oligo-Iz, d[A1Iz2A3OXOG4A5]*d[T5C4T3C2T1], and oligo-Oz, d[A1Oz2A3OXOG4A5]*d[T5C4T3C2T1], were optimized at the M06-2X/6-D95**//M06-2X/sto-3G level of theory in the aqueous phase using the ONIOM methodology; all the discussed energies were obtained at the M06-2X/6-31++G** level of theory. The non-equilibrated and equilibrated solvent-solute interactions were taken into consideration. The following results were found: (A) In all the discussed cases, OXOdG showed a higher predisposition to radical cation formation, and B) the excess electron migration toward Iz and Oz was preferred. However, in the case of oligo-Oz, the electron transfer from Oz2 to complementary C4 was noted during vertical to adiabatic anion relaxation, while for oligo-Iz, it was settled exclusively on the Iz2 moiety. The above was reflected in the charge transfer rate constant, vertical/adiabatic ionization potential, and electron affinity energy values, as well as the charge and spin distribution. It can be postulated that imidazolone moiety formation within the CDL ds-oligo structure and its conversion to oxazolone can significantly influence the charge migration process, depending on the C2 carbon hybridization sp2 or sp3. The above can confuse the single DNA damage recognition and removal processes, cause an increase in mutagenesis, and harm the effectiveness of anticancer therapy.
Assuntos
Dano ao DNA , Imidazóis , Imidazóis/química , Oxazolona/química , 8-Hidroxi-2'-Desoxiguanosina/química , DNA/química , Modelos Moleculares , Desoxiguanosina/química , Desoxiguanosina/análogos & derivados , TermodinâmicaRESUMO
Rice is a staple food for half of the world's population, but it is a poor dietary source of calcium (Ca) due to the low concentration. It is an important issue to boost Ca concentration in this grain to improve Ca deficiency risk, but the mechanisms underlying Ca accumulation are poorly understood. Here, we obtained a rice (Oryza sativa) mutant with high shoot Ca accumulation. The mutant exhibited 26%-53% higher Ca in shoots than did wild-type rice (WT) at different Ca supplies. Ca concentration in the xylem sap was 36% higher in the mutant than in the WT. There was no difference in agronomic traits between the WT and mutant, but the mutant showed 25% higher Ca in the polished grain compared with the WT. Map-based cloning combined with a complementation test revealed that the mutant phenotype was caused by an 18-bp deletion of a gene, OsK5.2, belonging to the Shaker-like K+ channel family. OsK5.2 was highly expressed in the mature region of the roots and its expression in the roots was not affected by Ca levels, but upregulated by low K. Immunostaining showed that OsK5.2 was mainly expressed in the pericycle of the roots. Taken together, our results revealed a novel role for OsK5.2 in Ca translocation in rice, and will be a good target for Ca biofortification in rice.
Assuntos
Oryza , Oryza/genética , Oryza/metabolismo , Cálcio/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Grão Comestível/genética , Grão Comestível/metabolismoRESUMO
AIM OF STUDY: We sought to compare MANAGE-PD and 5-2-1 Delphi criteria which are two commonly used and approved screening tools in Parkinson's Disease, in order to highlight their strengths and limitations. CLINICAL RATIONALE FOR STUDY: Timely intervention with device-aided therapies is vital as it enables improving motor symptoms, lowering the dosage and side-effects of dopaminergic treatment, and improving patients' and caregivers' quality of life. Various screening tools have been created to help clinicians find the best candidates for device-aided therapies (DAT) for advanced Parkinson's Disease. In this study, we aimed to compare the 5-2-1 Delphi criteria to MANAGE-PD to determine how they could be used specifically to maximise their potential. MATERIAL AND METHODS: All of the patients (260) included in this study were DAT-naive, > 18 years of age, diagnosed with Parkinson's Disease, and had been referred to the Department of Neurology for qualification for advanced therapies over a 4-year period (2019-2022). They were subjected to both 5-2-1 Delphi criteria and MANAGE-PD tools and divided into subgroups based on the results of the screening. The data of patients was then statistically analysed. RESULTS: In the study group, 51 patients (19.5%) met all three of the 5-2-1 criteria, and 123 (47.1%) patients were categorised as '3' in MANAGE-PD, meaning that they may benefit from DAT. Finally, at the local centre level, 64 (24.5%) patients were qualified for DAT. 22 (34.4%) patients who were qualified for DAT by a clinician did not meet the 5-2-1 criteria. CONCLUSIONS: The 5-2-1 scheme based on the data from this study was characterised by a 92.5% specificity level and 65.1% sensitivity level compared to 69.5% specificity and 98.4% sensitivity level of MANAGE-PD. CLINICAL IMPLICATIONS: We found that MANAGE-PD has a better screening potential of DAT admission than 5-2-1 criteria. While both tools are reliable and valuable in daily practice, our study suggests that some patients may be omitted when using only less complicated tools such as 5-2-1 during the assessment.
Assuntos
Técnica Delphi , Neurologistas , Doença de Parkinson , Humanos , Doença de Parkinson/terapia , Doença de Parkinson/diagnóstico , Feminino , Pessoa de Meia-Idade , Masculino , IdosoRESUMO
Pandemic of COVID-19 hit China at the end of 2022. According to China Center for Disease Control and Prevention, Omicron BA.5.2 and BF.7 were the main circulating variants. Chinese people had a high COVID-19 vaccination rate, and the most widely used vaccines were CoronaVac (Sinovac) and BBIBP-CorV (Sinopharm). An online questionnaire was distributed to survey the vaccination history and infection information of China mainland residents during this pandemic. A total of 4250 subjects were included for propensity score matching, 566 unvaccinated subjects and 1072 vaccinated subjects were finally included to analyze the effects of the two vaccines on BA.5.2 and BF.7. The SARS-CoV-2 infection rate was 84.5% in the vaccinated group and 82.3% in the unvaccinated group (p = 0.255). Vaccinated subjects had significantly higher rates of COVID-19-related symptoms, including fever, cough, nasal obstruction, runny nose, and sore throat. However, vaccinated people had lower risk of pneumonia (odds ratio [OR]: 0.467, 95% confidence interval [CI]: 0.286-0.762) and hospitalization (OR: 0.290, 95% CI: 0.097-0.870) due to COVID-19. In general, the current study did not observe the protective effect of CoronaVac and BBIBP CorV against BA.5.2 and BF.7 infection. However, these vaccines can still reduce the risk of adverse outcomes such as pneumonia and hospitalization.
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COVID-19 , Vacinas , Humanos , SARS-CoV-2 , Vacinas contra COVID-19 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Estudos Retrospectivos , China/epidemiologiaRESUMO
The initial severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron subvariants, BA.1 and BA.2, are being progressively displaced by BA.5 in many countries. To provide insight on the replacement of BA.2 by BA.5 as the dominant SARS-CoV-2 variant, we performed a comparative analysis of Omicron BA.2.12.1 and BA.5.2 variants in cell culture and hamster models. We found that BA.5.2 exhibited enhanced replicative kinetics over BA.2.12.1 in vitro and in vivo, which is evidenced by the dominant BA.5.2 viral genome detected at different time points, regardless of immune selection pressure with vaccine-induced serum antibodies. Utilizing reverse genetics, we constructed a mutant SARS-CoV-2 carrying spike F486V substitution, which is an uncharacterized mutation that concurrently discriminates Omicron BA.5.2 from BA.2.12.1 variant. We noticed that the 486th residue does not confer viral replication advantage to the virus. We also found that 486V displayed generally reduced immune evasion capacity when compared with its predecessor, 486F. However, the surge of fitness in BA.5.2 over BA.2.12.1 was not due to stand-alone F486V substitution but as a result of the combination of multiple mutations. Our study upholds the urgency for continuous monitoring of SARS-CoV-2 Omicron variants with enhanced replication fitness.
Assuntos
COVID-19 , Animais , Cricetinae , Humanos , SARS-CoV-2/genética , Técnicas de Cultura de Células , Genoma Viral , Glicoproteína da Espícula de Coronavírus/genética , Anticorpos Antivirais , Anticorpos NeutralizantesRESUMO
BACKGROUND: The purpose of this study was to investigate the differences between the clinical characteristics and the factors influencing liver injury in patients with the Omicron subvariant BA.5.2 (Omicron BA.5.2) and the prototype of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). METHODS: Between December 30, 2019 and November 30, 2022, 157 patients infected with the SARS-CoV-2 prototype and 199 patients infected with the Omicron BA.5.2 were included in this case-control, single-center, retrospective study. Differences in clinical characteristics and liver injury between the Omicron BA.5.2 patients and the prototype patients were subsequently analyzed. RESULTS: None of the Omicron BA.5.2 patients reached the critical state, and showed relatively milder symptoms including fever, cough, headache, muscle soreness, nausea or vomiting, diarrhea, anorexia and hypoxia. The Omicron BA.5.2 had a lower effect on body temperature (T), white blood cell (WBC) count, hematocrit (HCT), C-reactive protein (CRP) level, D-dimer, finger pulse oxygen saturation (SpO2) and lung lesions. The differences in liver injury between the two groups were related to the severity of the disease, T, blood oxygen levels, albumin (ALB), CRP, and medication usage. Gender, body mass index, and CRP levels influenced liver damage in the Omicron BA.5.2 patients. In particular, CRP was an independent risk factor for liver injury. Because the severity of liver function damage was considerably low, only a small number of Omicron BA.5.2 patients required liver-protective treatment. CONCLUSION: Liver injury is expected in the COVID-19 patients. The Omicron BA.5.2 patients showed milder symptoms of liver injury than the prototype patients. However, dynamic monitoring of liver function is warranted, especially for individuals presenting with elevated levels of CRP.
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COVID-19 , Fígado , SARS-CoV-2 , Humanos , Albuminas , COVID-19/complicações , Fígado/lesões , Estudos RetrospectivosRESUMO
With numbers of COVID-19 cases having substantially increased at the end of 2022 in China, some countries have started or expanded testing and genomic surveillance of travellers. We report screening results in Italy in late December 2022 of 556 flight passengers in provenance from two Chinese provinces. Among these passengers, 126 (22.7%) tested SARS-CoV-2 positive. Whole genome sequencing of 61 passengers' positive samples revealed Omicron variants, notably sub-lineages BA.5.2.48, BF.7.14 and BQ.1.1, in line with data released from China.
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COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , Genômica , China/epidemiologia , Itália/epidemiologiaRESUMO
Optically active citramalic acid (CMA) is naturally present as an acidic taste component in fruits, such as apples. The absolute configuration of CMA in such fruits was investigated by high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) following pre-column derivatization with a chiral reagent, benzyl 5-(2-aminoethyl)-3-methyl-4-oxoimidazolidine-1-carboxylate. The developed LC-MS/MS method successfully separated the enantiomers of CMA using an octadecylsilica column with a resolution and separation factor of 2.19 and 1.09, respectively. Consequently, the R-form of CMA was detected in the peel and fruit of three kinds of apple at concentrations in the 1.24-37.8 and 0.138-1.033 mg/wet 100 g ranges, respectively. In addition, R- CMA was present in commercial apple juice, whereas no quantity was detected in commercial blueberry, perilla, or Japanese apricot juice.
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Malus , Cromatografia Líquida/métodos , Malus/química , Espectrometria de Massas em Tandem/métodos , Sucos de Frutas e Vegetais , Cromatografia Líquida de Alta Pressão/métodos , Frutas/química , EstereoisomerismoRESUMO
Acacia saligna growing in Australia has not been fully investigated for its bioactive phytochemicals. Sequential polarity-based extraction was employed to provide four different extracts from individual parts of A. saligna. Bioactive extracts were determined using in vitro antioxidant and yeast α-glucosidase inhibitory assays. Methanolic extracts from barks, leaves, and flowers are the most active and have no toxicity against 3T3-L1 adipocytes. Compound isolation of bioactive extracts provided us with ten compounds. Among them are two novel natural products; naringenin-7-O-α-L-arabinopyranoside 2 and (3S*,5S*)-3-hydroxy-5-(2-aminoethyl) dihydrofuran-2(3H)-one 9. D-(+)-pinitol 5a (from barks and flowers), (-)-pinitol 5b (exclusively from leaf), and 2,4-di-t-butylphenol 7 are known natural products and new to A. saligna. (-)-Epicatechin 6, quercitrin 4, and myricitrin 8 showed potent antioxidant activities consistently in DPPH and ABTS assays. (-)-Epicatechin 6 (IC50 = 63.58 µM),D-(+)-pinitol 5a (IC50 = 74.69 µM), and naringenin 1 (IC50 = 89.71 µM) are the strong inhibitors against the α-glucosidase enzyme. The presence of these compounds supports the activities exerted in our methanolic extracts. The presence of 2,4-di-t-butylphenol 7 may support the reported allelopathic and antifungal activities. The outcome of this study indicates the potential of Australian A. saligna as a rich source of bioactive compounds for drug discovery targeting type 2 diabetes.
Assuntos
Acacia , Catequina , Diabetes Mellitus Tipo 2 , Humanos , Extratos Vegetais/química , Antioxidantes/química , alfa-Glucosidases , Austrália , Compostos Fitoquímicos/farmacologiaRESUMO
This review aims to summarize the effects of intermittent fasting on markers of cardiometabolic health in humans. All forms of fasting reviewed here-alternate-day fasting (ADF), the 5:2 diet, and time-restricted eating (TRE)-produced mild to moderate weight loss (1-8% from baseline) and consistent reductions in energy intake (10-30% from baseline). These regimens may benefit cardiometabolic health by decreasing blood pressure, insulin resistance, and oxidative stress. Low-density lipoprotein cholesterol and triglyceride levels are also lowered, but findings are variable. Other health benefits, such as improved appetite regulation and favorable changes in the diversity of the gut microbiome, have also been demonstrated, but evidence for these effects is limited. Intermittent fasting is generally safe and does not result in energy level disturbances or increased disordered eating behaviors. In summary, intermittent fasting is a safe diet therapy that can produce clinically significant weight loss (>5%) and improve several markers of metabolic health in individuals with obesity.