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1.
FASEB J ; 38(17): e70013, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39225365

RESUMO

Articular cartilage phenotypic homeostasis is crucial for life-long joint function, but the underlying cellular and molecular mechanisms governing chondrocyte stability remain poorly understood. Here, we show that the protein tyrosine phosphatase SHP2 is differentially expressed in articular cartilage (AC) and growth plate cartilage (GPC) and that it negatively regulates cell proliferation and cartilage phenotypic program. Postnatal SHP2 deletion in Prg4+ AC chondrocytes increased articular cellularity and thickness, whereas SHP2 deletion in Acan+ pan-chondrocytes caused excessive GPC chondrocyte proliferation and led to joint malformation post-puberty. These observations were verified in mice and in cultured chondrocytes following treatment with the SHP2 PROTAC inhibitor SHP2D26. Further mechanistic studies indicated that SHP2 negatively regulates SOX9 stability and transcriptional activity by influencing SOX9 phosphorylation and promoting its proteasome degradation. In contrast to published work, SHP2 ablation in chondrocytes did not impact IL-1-evoked inflammation responses, and SHP2's negative regulation of SOX9 could be curtailed by genetic or chemical SHP2 inhibition, suggesting that manipulating SHP2 signaling has translational potential for diseases of cartilage dyshomeostasis.


Assuntos
Cartilagem Articular , Condrócitos , Osteoartrite , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Fatores de Transcrição SOX9 , Fatores de Transcrição SOX9/metabolismo , Fatores de Transcrição SOX9/genética , Animais , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Condrócitos/metabolismo , Condrócitos/patologia , Camundongos , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Osteoartrite/metabolismo , Osteoartrite/patologia , Proliferação de Células , Células Cultivadas , Camundongos Endogâmicos C57BL , Camundongos Knockout , Masculino
2.
Cancer Lett ; 604: 217203, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39236847
4.
Int J Antimicrob Agents ; : 107331, 2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39251094

RESUMO

BACKGROUND: Vonoprazan, the new acid suppressive drug, provides more choices for eradicating H. pylori. Therefore, whether vonoprazan and high dose amoxicillin dual therapy is more effective and safer requires a systematic analysis. MATERIALS AND METHODS: A comprehensive search of the literature from PubMed, Embase, Cochrane Library, Web of Science database, up to May 16, 2024. Trails evaluating H. pylori eradicating rates, adverse events, and compliance of VHA dual therapy compared with other therapies were included. RevMan 5.4 was used for statistical analysis. RESULTS: 11 RCTs and 2 retrospective clinical studies with 4570 samples were included. The VHA dual therapy has superior H. pylori eradicating rates (ITT: 86.0% vs 80.7%, OR=1.36, 95% CI 1.07-1.73, P=0.01; PP: 90.6% vs 85.7%, OR=1.42, 95% CI 1.07-1.88, P=0.02), fewer adverse events(15.4% vs 27.7%, OR=0.49, 95%CI 0.35-0.68, P<0.0001), and similar compliance (94.6% vs 93.2%, OR=1.27, 95% CI 0.98-1.64, P=0.07) in comparison to other guideline therapies. According to subgroup analysis with PP data, VHA is more effective than P-BQT (93.5% vs 89.3%, OR=1.76, 95% CI 1.03-3.00, P=0.04). In addition, the eradicating rates of 10-day and 14-day VHA were 92% (95% CI 0.91-0.94) and 93% (95% CI 0.90-0.97) respectively, with the 7-day VHA 65% (95% CI 0.55-0.75). CONCLUSION: VHA dual therapy, for 10 or 14 days showed superior efficacy and safety comparing with therapies recommended by the guidelines, should be prioritized for adoption.

5.
PLoS Negl Trop Dis ; 18(9): e0012439, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39235995

RESUMO

BACKGROUND: Hemorrhagic fever with renal syndrome (HFRS) is a severe public health problem in Jiangxi province, China. Previous studies reported genetic variants of Orthohantavirus hantanense (Hantaan virus, HTNV) in rodents in this area. However, the relationship between HTNV variants and human infection needs to be confirmed. This study aimed to identify the HTNV variants in patients and to understand the clinical characteristics of HFRS caused by these variants. METHODS: Samples were collected from hospitalized suspected cases of HFRS during the acute phase. HFRS cases were confirmed using quantitative real-time RT-PCR. Peripheral blood mononuclear cells (PBMC) from patients with HFRS were inoculated into Vero-E6 cells for viral isolation. The genomic sequences of HTNV from patients were obtained by amplicon-based next-generation sequencing. A retrospective analysis was conducted on the clinical characteristics of the patients. RESULTS: HTNV RNA was detected in 53 of 183 suspected HFRS patients. Thirteen HTNVs were isolated from 32 PBMCs of HFRS cases. Whole genome sequences of 14 HTNVs were obtained, including 13 isolates in cell culture from 13 patients, and one from plasma of the fatal case which was not isolated successfully in cell culture. Genetic analysis revealed that the HTNV sequence from the 14 patients showed significant variations in nucleotide and amino acid to the HTNV strains found in other areas. Fever (100%, 53/53), thrombocytopenia (100%, 53/53), increased serum aspartate aminotransferase (100%, 53/53), and increased lactate dehydrogenase (96.2%, 51/53) were the most common characteristics. Severe acute kidney injury was observed in 13.2% (7/53) of cases. Clinical symptoms, such as pain, petechiae, and gastrointestinal or respiratory symptoms were uncommon. CONCLUSION: The HTNV genetic variants cause human infections in Jiangxi. The clinical symptoms of HFRS caused by the HTNV genetic variant during the acute phase are atypical. In addition to renal dysfunction, attention should be paid to the common liver injuries caused by these genetic variants.


Assuntos
Variação Genética , Febre Hemorrágica com Síndrome Renal , Humanos , Febre Hemorrágica com Síndrome Renal/virologia , Febre Hemorrágica com Síndrome Renal/epidemiologia , China/epidemiologia , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Chlorocebus aethiops , Animais , Células Vero , Filogenia , RNA Viral/genética , Adulto Jovem , Estudos Retrospectivos , Leucócitos Mononucleares/virologia , Idoso , Genoma Viral , Orthohantavírus/genética , Orthohantavírus/isolamento & purificação , Orthohantavírus/classificação , Adolescente , Vírus Hantaan/genética , Vírus Hantaan/isolamento & purificação , Vírus Hantaan/classificação
6.
Mol Biol Evol ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39248185

RESUMO

The heterogeneous landscape of genomic variation has been well documented in population genomic studies. However, disentangling the intricate interplay of evolutionary forces influencing the genetic variation landscape over time remains challenging. In this study, we assembled a chromosome-level genome for Castanopsis eyrei and sequenced the whole genomes of 276 individuals from 12 Castanopsis species, spanning a broad divergence continuum. We found highly correlated genomic variation landscapes across these species. Furthermore, variations in genetic diversity and differentiation along the genome were strongly associated with recombination rates and gene density. These results suggest that long-term linked selection and conserved genomic features have contributed to the formation of a common genomic variation landscape. By examining how correlations between population summary statistics change throughout the species divergence continuum, we determined that background selection alone does not fully explain the observed patterns of genomic variation; the effects of recurrent selective sweeps must be considered. We further revealed that extensive gene flow has significantly influenced patterns of genomic variation in Castanopsis species. The estimated admixture proportion correlated positively with recombination rate and negatively with gene density, supporting a scenario of selection against gene flow. Additionally, putative introgression regions exhibited strong signals of positive selection, an enrichment of functional genes, and reduced genetic burdens, indicating that adaptive introgression has played a role in shaping the genomes of hybridizing species. This study provides insights into how different evolutionary forces have interacted in driving the evolution of the genomic variation landscape.

7.
Zhongguo Zhong Yao Za Zhi ; 49(14): 3894-3900, 2024 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-39099363

RESUMO

This study explored the effect of Tianma Gouteng Decoction on oxidative stress induced by angiotensin Ⅱ(AngⅡ) in vascular smooth muscle cell(VSMC) and its molecular mechanism. Primary rat VSMC were cultured using tissue block method, and VSMC were identified by α-actin immunofluorescence staining. AngⅡ at a concentration of 1×10~(-6) mol·L~(-1) was used as the stimulating factor, and Sprague Dawley(SD) rats were orally administered with Tianma Gouteng Decoction to prepare drug serum. Rat VSMC were divided into normal group, model group, Chinese medicine group, and inhibitor(3-methyladenine, 3-MA) group. Cell counting kit-8(CCK-8) assay was used to detect cell proliferation activity. Bromodeoxyuridine(BrdU) flow cytometry was used to detect cell cycle. Transwell assay was used to detect cell migration ability. Enzyme-linked immunosorbent assay(ELISA) was used to detect the activity of superoxide dismutase(SOD), catalase(CAT), and malondialdehyde(MDA) in VSMC. The intracellular reactive oxygen species(ROS) fluorescence intensity was detected using DCFH-DA fluorescent probe. Western blot was used to detect the expression of PTEN-induced putative kinase 1(PINK1), Parkin, p62, and microtubule-associated protein 1A/1B-light chain 3(LC3-Ⅱ) proteins in VSMC. The results showed that Tianma Gouteng Decoction-containing serum at a concentration of 8% could significantly inhibit VSMC growth after 48 hours of intervention. Compared with the normal group, the model group showed significantly increased cell proliferation activity and migration, significantly decreased levels of SOD and CAT, significantly increased levels of MDA, significantly enhanced ROS fluorescence intensity, significantly decreased expression of PINK1, Parkin, and LC3-Ⅱ proteins, and significantly increased expression of p62 protein. Compared with the model group, the Chinese medicine group showed significantly reduced cell proliferation activity and migration, significantly increased levels of SOD and CAT, significantly decreased levels of MDA, significantly weakened ROS fluorescence intensity, significantly increased expression of PINK1, Parkin, and LC3-Ⅱ proteins, and significantly decreased expression of p62 protein. Compared with the Chinese medicine group, the addition of the mitochondrial autophagy inhibitor 3-MA could block the intervention of Tianma Gouteng Decoction-containing serum on VSMC proliferation, migration, mitochondrial autophagy, and oxidative stress levels, with statistically significant differences. In summary, Tianma Gouteng Decoction has good antioxidant activity and can inhibit cell proliferation and migration. Its mechanism of action may be related to the activation of the mitochondrial autophagy PINK1/Parkin signaling pathway.


Assuntos
Angiotensina II , Proliferação de Células , Medicamentos de Ervas Chinesas , Músculo Liso Vascular , Estresse Oxidativo , Proteínas Quinases , Ratos Sprague-Dawley , Ubiquitina-Proteína Ligases , Animais , Medicamentos de Ervas Chinesas/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Masculino , Proliferação de Células/efeitos dos fármacos , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Proteínas Quinases/metabolismo , Proteínas Quinases/genética , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Movimento Celular/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Células Cultivadas , Superóxido Dismutase/metabolismo
9.
Nature ; 632(8027): 1009-1013, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39143219

RESUMO

The nucleus of almost all massive galaxies contains a supermassive black hole (BH)1. The feedback from the accretion of these BHs is often considered to have crucial roles in establishing the quiescence of massive galaxies2-14, although some recent studies show that even galaxies hosting the most active BHs do not exhibit a reduction in their molecular gas reservoirs or star formation rates15-17. Therefore, the influence of BHs on galaxy star formation remains highly debated and lacks direct evidence. Here, based on a large sample of nearby galaxies with measurements of masses of both BHs and atomic hydrogen (HI), the main component of the interstellar medium18, we show that the HI gas mass to stellar masses ratio (µHI = MHI/M⋆) is more strongly correlated with BH masses (MBH) than with any other galaxy parameters, including stellar mass, stellar mass surface density and bulge masses. Moreover, once the µHI-MBH correlation is considered, µHI loses dependence on other galactic parameters, demonstrating that MBH serves as the primary driver of µHI. These findings provide important evidence for how the accumulated energy from BH accretion regulates the cool gas content in galaxies, by ejecting interstellar medium gas and/or suppressing gas cooling from the circumgalactic medium.

10.
J Chiropr Educ ; 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39177451

RESUMO

OBJECTIVE: Evidence-based radiographic guidelines are used to justify the need for radiographs and prevent their overuse. This study aimed to assess whether 4th-year chiropractic interns at the International Medical University plan to use x-ray imaging in their future private practice in line with the principles taught throughout their chiropractic program and the evidence-based imaging guidelines. METHODS: A survey questionnaire was distributed to 74 final year chiropractic interns, with 62 completed responses. The questionnaire consisted of 8 case scenarios representing potential chiropractic patients. The interns were asked to decide whether to x-ray the patient or not, and which x-ray views to request if they chose to x-ray the patient. RESULTS: Results were compared with the gold standard using percentage agreement. The findings revealed that the chiropractic students adhered to the gold standard answers for 6 out of 8 cases. However, they did not perform well in selecting the correct x-ray views for the 3 cases where radiography was indicated by the gold standard. CONCLUSION: Results suggest that while the interns have a good understanding of when radiography is necessary, they may need additional training in selecting the appropriate x-ray views for each case.

11.
Environ Pollut ; 360: 124677, 2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39127336

RESUMO

Mitochondria, as the powerhouse of the cell, play a vital role in maintaining cellular energy homeostasis and are known to be a primary target of cadmium (Cd) toxicity. The improper targeting of proteins to mitochondria can compromise the normal functions of the mitochondria. However, the precise mechanism by which protein localization contributes to the development of mitochondrial dysfunction induced by Cd is still not fully understood. For this research, Hy-Line white variety chicks (1-day-old) were used and equally distributed into 4 groups: the Control group (fed with a basic diet), the Cd35 group (basic diet with 35 mg/kg CdCl2), the Cd70 group (basic diet with 70 mg/kg CdCl2) and the Cd140 group (basic diet with 140 mg/kg CdCl2), respectively for 90 days. It was found that Cd caused the accumulation of heat shock factor 1 (HSF1) in the mitochondria, and the overexpression of HSF1 in the mitochondria led to mitochondrial dysfunction and neuronal damage. This process is due to the mitochondrial HSF1 (mtHSF1), causing mitochondrial fission through the upregulation of dynamin-related protein 1 (Drp1) content, while inhibiting oligomer formation of single-stranded DNA-binding protein 1 (SSBP1), resulting in the mitochondrial DNA (mtDNA) deletion. The findings unveil an unforeseen role of HSF1 in triggering mitochondrial dysfunction.


Assuntos
Cádmio , Galinhas , Fatores de Transcrição de Choque Térmico , Mitocôndrias , Cádmio/toxicidade , Animais , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Fatores de Transcrição de Choque Térmico/genética , Fatores de Transcrição de Choque Térmico/metabolismo , DNA Mitocondrial/genética , Dinâmica Mitocondrial/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos
12.
Adv Sci (Weinh) ; : e2310126, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39044361

RESUMO

There is an urgent need to fully understand the biology of third generation EGFR-tyrosine kinase inhibitors (EGFR-TKIs), particularly osimertinib, and to develop mechanism-driven strategies to manage their acquired resistance. Transient receptor potential melastatin-2 (TRPM2) functions as an important regulator of Ca2+ influx, but its role in mediating therapeutic efficacies of EGFR-TKIs and acquired resistance to EGFR-TKIs has been rarely studied. This study has demonstrated a previously undiscovered role of suppression of TRPM2 and subsequent inhibition of Ca2+ influx and induction of ROS and DNA damage in mediating apoptosis induction and the therapeutic efficacy of osimertinib against EGFR mutant NSCLC. The rebound elevation represents a key mechanism accounting for the emergence of acquired resistance to osimertinib and other third generation EGFR-TKIs. Accordingly, targeting TRPM2 is a potentially promising strategy for overcoming and preventing acquired resistance to osimertinib, warranting further study in this direction including the development of cancer therapy-optimized TRPM2 inhibitors.

13.
Carbohydr Polym ; 342: 122332, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39048187

RESUMO

High-amylose maize starch (69.3 % amylose) was debranched to increase the level of linear molecules and enhance the formation of spherulites. Debranched high-amylose maize starch (25 %, w/w) was heated to 180 °C in a Parr reactor followed by crystallization at different temperatures between 25 and 150 °C. The objectives of this study were to investigate the effects of crystallization temperature on the yield, morphology, structure, crystallinity, and digestibility of the spherulites formed. When the crystallization temperature was 150 °C, spherulites with negative birefringent sign were formed. High crystallization temperature caused molecular degradation and the degree of degradation was severe at 150 °C, resulting in relatively short chain amylose (DP < 150). When crystallized at 25 to 120 °C, spherulites with strong positive birefringence were produced. The long chain amylose was attributed to the positive birefringence. All spherulites had a predominant B-type crystalline structure. The spherulites with negative birefringence showed a lower degree of crystallinity and lower resistance to enzyme digestion, but all the spherulites with positive birefringence had a high resistant starch content (89-94 %). α-Amylase was not able to penetrate inside the spherulites as revealed by the confocal laser scanning microscopic images.


Assuntos
Amilose , Cristalização , Zea mays , Zea mays/química , Amilose/química , Amido/química , Temperatura , Hidrólise
14.
World J Gastrointest Oncol ; 16(6): 2646-2662, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38994157

RESUMO

BACKGROUND: Colon cancer (CC) occurrence and progression are considerably influenced by the tumor microenvironment. However, the exact underlying regulatory mechanisms remain unclear. AIM: To investigate immune infiltration-related differentially expressed genes (DEGs) in CC and specifically explored the role and potential molecular mechanisms of complement factor I (CFI). METHODS: Immune infiltration-associated DEGs were screened for CC using bioinformatics. Quantitative reverse transcription polymerase chain reaction was used to examine hub DEGs expression in the CC cell lines. Stable CFI-knockdown HT29 and HCT116 cell lines were constructed, and the diverse roles of CFI in vitro were assessed using CCK-8, 5-ethynyl-2'-deoxyuridine, wound healing, and transwell assays. Hematoxylin and eosin staining and immunohistochemistry staining were employed to evaluate the influence of CFI on the tumorigenesis of CC xenograft models constructed using BALB/c male nude mice. Key proteins associated with glycolysis and the Wnt pathway were measured using western blotting. RESULTS: Six key immune infiltration-related DEGs were screened, among which the expression of CFI, complement factor B, lymphoid enhancer binding factor 1, and SRY-related high-mobility-group box 4 was upregulated, whereas that of fatty acid-binding protein 1, and bone morphogenic protein-2 was downregulated. Furthermore, CFI could be used as a diagnostic biomarker for CC. Functionally, CFI silencing inhibited CC cell proliferation, migration, invasion, and tumor growth. Mechanistically, CFI knockdown downregulated the expression of key glycolysis-related proteins (glucose transporter type 1, hexokinase 2, lactate dehydrogenase A, and pyruvate kinase M2) and the Wnt pathway-related proteins (ß-catenin and c-Myc). Further investigation indicated that CFI knockdown inhibited glycolysis in CC by blocking the Wnt/ß-catenin/c-Myc pathway. CONCLUSION: The findings of the present study demonstrate that CFI plays a crucial role in CC development by influencing glycolysis and the Wnt/ß-catenin/c-Myc pathway, indicating that it could serve as a promising target for therapeutic intervention in CC.

15.
Front Microbiol ; 15: 1396699, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38957618

RESUMO

Background: Previous research has hinted at a crucial link between gut microbiota and arterial embolism and thrombosis, yet the causal relationship remains enigmatic. To gain a deeper understanding, we aimed to comprehensively explore the causal relationship and elucidate the impact of the gut microbiota on the risk through a two-sample Mendelian randomization (MR) study. Methods: Genetic instrumental variables for gut microbiota were identified from a genome-wide association study (GWAS) of 18,340 participants. Summary statistics for IBS were drawn from a GWAS including 1,076 cases and 381,997 controls. We used the inverse-variance weighted (IVW) method as the primary analysis. To test the robustness of our results, we further performed the weighted median method, MR-Egger regression, and MR pleiotropy residual sum and outlier test. Results: We identified three bacterial traits that were associated with the risk of arterial embolism and thrombosis: odds ratio (OR): 1.58, 95% confidence interval (CI): 1.08-2.31, p = 0.017 for genus Catenibacterium; OR: 0.64, 95% CI: 0.42-0.96, p = 0.031 for genus Dialister; and OR: 2.08, 95% CI: 1.25-3.47, p = 0.005 for genus Odoribacter. The results of sensitivity analyses for these bacterial traits were consistent (P<0.05). Conclusion: Our systematic analyses provided evidence to support a potential causal relationship between several gut microbiota taxa and the risk of arterial embolism and thrombosis. More studies are required to show how the gut microbiota affects the development of arterial embolism and thrombosis.

16.
Int Immunopharmacol ; 138: 112616, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-38959544

RESUMO

Intervertebral disc degeneration (IDD) is the leading cause of low back pain, which is one of the major factors leading to disability and severe economic burden. Necroptosis is an important form of programmed cell death (PCD), a highly regulated caspase-independent type of cell death that is regulated by receptor-interacting protein kinase 1 (RIPK1), RIPK3 and mixed lineage kinase domain-like protein (MLKL)-mediated, play a key role in the pathophysiology of various inflammatory, infectious and degenerative diseases. Recent studies have shown that necroptosis plays an important role in the occurrence and development of IDD. In this review, we provide an overview of the initiation and execution of necroptosis and explore in depth its potential mechanisms of action in IDD. The analysis focuses on the connection between NP cell necroptosis and mitochondrial dysfunction-oxidative stress pathway, inflammation, endoplasmic reticulum stress, apoptosis, and autophagy. Finally, we evaluated the possibility of treating IDD by inhibiting necroptosis, and believed that targeting necroptosis may be a new strategy to alleviate the symptoms of IDD.


Assuntos
Degeneração do Disco Intervertebral , Necroptose , Humanos , Degeneração do Disco Intervertebral/terapia , Degeneração do Disco Intervertebral/patologia , Animais , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Apoptose , Autofagia , Estresse Oxidativo , Proteínas Quinases/metabolismo
17.
Vet Sci ; 11(7)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-39057972

RESUMO

(1) Background: One method of eradicating brucellosis is to cull cattle that test positive for antibodies 12 months after being vaccinated with the 19-strain vaccine. Variations in immunization regimens and feeding practices may contribute to differences in the rate of persistent antibodies. We conducted this study to investigate the real positive rate of Brucella antibody in field strains of Brucella spp. after immunization over 12 months in dairy cows. This research aims to provide data to support the development of strategies for preventing, controlling, and eradicating brucellosis. (2) Method: We employed the baseline sampling method to collect samples from cows immunized with the A19 vaccine for over 12 months in Lingwu City from 2021 to 2023. Serological detection was conducted using the RBPT method. An established PCR method that could distinguish between 19 and non-19 strains of Brucella was utilized to investigate the field strains of Brucella on 10 dairy farms based on six samples mixed into one using the Mathematical Expectation strategy. (3) Results: We analyzed the rates of individual seropositivity and herd seropositive rates in dairy cattle in Lingwu City from 2021 to 2023 and revealed that antibodies induced by the Brucella abortus strain A19 vaccine persist in dairy herds for more than 12 months. We established a PCR method for identifying both Brucella A19 and non-A19 strains, resulting in the detection of 10 field strains of Brucella abortus from 1537 dairy cows. By employing a Mathematical Expectation strategy, we completed testing of 1537 samples after conducting only 306 tests, thereby reducing the workload by 80.1%. (4) Conclusions: There was a certain proportion of cows with a persistent antibody titer, but there was no evidence that all of these cattle were naturally infected with Brucella. The established PCR method for distinguishing between Brucella abortus strain 19 and non-19 strains can be specifically utilized for detecting natural Brucella infection in immunized cattle. We propose that relying solely on the detection of antibodies in cattle immunized with the A19 vaccine more than 12 months previously should not be solely relied upon as a diagnostic basis for brucellosis, and it is essential to complement this approach with PCR analysis to specifically identify field Brucella spp. Brucella abortus was the predominant strain identified in the field during this study. Detection based on the Mathematical Expectation strategy can significantly enhance detection efficiency.

19.
Antonie Van Leeuwenhoek ; 117(1): 102, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012584

RESUMO

This study represents the first analysis of the bacterial community in chickens affected by swollen head syndrome, utilizing 16S rRNA gene sequencing. Samples were obtained from clinical laying chickens and were examined for the presence of Avibacterium paragallinarum (APG) and Ornithobacterium rhinotracheale (ORT) using conventional polymerase chain reaction (PCR). From the samples, five APG-positive (APG) and APG-negative (N-APG) samples were chosen, along with five specific pathogen-free chickens, for 16S rRNA gene sequencing. Results showed that APG and ORT were widely detected in the chicken samples with swollen head syndrome (SHS, 9/10), while APG was detected in all five specific pathogen-free (SPF) samples. In contrast, conventional PCR sensitivity was found to be inadequate for diagnosis, with only 35.7% (5/14) and 11.1% (1/9) sensitivity for APG and ORT, respectively, based on 16S rRNA gene sequencing data. Furthermore, 16S rRNA gene sequencing was able to quantify the bacteria in the samples, revealing that the relative abundance of APG in the APG group ranged from 2.7 to 81.3%, while the relative abundance of APG in the N-APG group ranged from 0.1 to 21.0%. Notably, a low level of APG was also detected in all 5 SPF samples. The study also identified a significant number of animal and human common bacterial pathogens, including but not limited to Gallibacterium anatis, Riemerella columbina, Enterococcus cecorum, Mycoplasma synoviae, Helicobacter hepaticus, and Staphylococcus lentus. In conclusion, 16S rRNA gene sequencing is a valuable tool for bacterial pathogen diagnosis and the discovery of novel bacterial pathogens, while conventional PCR is not reliable for diagnosis.


Assuntos
Galinhas , Reação em Cadeia da Polimerase , Doenças das Aves Domésticas , RNA Ribossômico 16S , RNA Ribossômico 16S/genética , Animais , Galinhas/microbiologia , Reação em Cadeia da Polimerase/métodos , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/diagnóstico , Bactérias/genética , Bactérias/classificação , Bactérias/isolamento & purificação , DNA Bacteriano/genética , Análise de Sequência de DNA , Filogenia
20.
Phys Rev E ; 109(5-2): 055305, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38907478

RESUMO

Literature studies of the lattice Boltzmann method (LBM) demonstrate hydrodynamics beyond the continuum limit. This includes exact analytical solutions to the LBM, for the bulk velocity and shear stress of Couette flow under diffuse reflection at the walls through the solution of equivalent moment equations. We prove that the bulk velocity and shear stress of Couette flow with Maxwell-type boundary conditions at the walls, as specified by two-dimensional isothermal lattice Boltzmann models, are inherently linear in Mach number. Our finding enables a systematic variational approach to be formulated that exhibits superior computational efficiency than the previously reported moment method. Specifically, the number of partial differential equations (PDEs) in the variational method grows linearly with quadrature order while the number of moment method PDEs grows quadratically. The variational method directly yields a system of linear PDEs that provide exact analytical solutions to the LBM bulk velocity field and shear stress for Couette flow with Maxwell-type boundary conditions. It is anticipated that this variational approach will find utility in calculating analytical solutions for novel lattice Boltzmann quadrature schemes and other flows.

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