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1.
Phys Rev Lett ; 132(21): 211804, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38856254

RESUMO

We measure the tau-to-light-lepton ratio of inclusive B-meson branching fractions R(X_{τ/ℓ})≡B(B→Xτν)/B(B→Xℓν), where ℓ indicates an electron or muon, and thereby test the universality of charged-current weak interactions. We select events that have one fully reconstructed B meson and a charged lepton candidate from 189 fb^{-1} of electron-positron collision data collected with the Belle II detector. We find R(X_{τ/ℓ})=0.228±0.016(stat)±0.036(syst), in agreement with standard-model expectations. This is the first direct measurement of R(X_{τ/ℓ}).

2.
Public Health ; 226: 248-254, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38091813

RESUMO

OBJECTIVES: Carotid intima-media thickness (CIMT) is a noninvasive marker of atherosclerosis, a typical pathologic process underlying cardiovascular diseases (CVDs). It is essential to explore the relationships between weight loss and the reduction of CIMT. STUDY DESIGN: This was an updated systematic review and meta-analysis. METHODS: A systematic literature search was conducted to collect relevant clinical trials. The pooled results of meta-analyses were assessed by weighted mean difference (WMD) and the corresponding 95 % confidence interval (95% CI). RESULTS: Thirty-three articles involving 2273 participants were collected in this meta-analysis. Among all participants with obesity, the pooled mean of weight loss was -23.26 kg (95% CI: -27.71 to -18.81), and the pooled mean change of CIMT was -0.06 mm (95% CI: -0.08 to -0.04). Compared with Non-surgical interventions, Surgical ones could lead to much higher weight loss (Pbetween groups < 0.001). A more significant CIMT reduction was identified among Surgical intervention patients than among Non-surgical intervention participants (Pbetween groups < 0.001). CONCLUSIONS: Effective interventions, especially Surgical interventions, could reduce the weight of patients with obesity, followed by the decline of CIMT, which might further disturb atherosclerosis progression and lower CVD risk.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Humanos , Fatores de Risco , Espessura Intima-Media Carotídea , Obesidade/complicações , Redução de Peso
3.
Tech Coloproctol ; 28(1): 40, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38507096

RESUMO

BACKGROUND: Resection and strictureplasty are the two surgical modalities used in the management of Crohn's disease (CD). The objective of this study was to compare morbidity and clinical recurrence between patients who underwent strictureplasty and patients who underwent resection. METHODS: Patients with CD who underwent strictureplasty between January 2012 and December 2022 were enrolled. The patients were well matched with patients who underwent resection without strictureplasty. Patient- and disease-specific characteristics, postoperative morbidity, and clinical recurrence were also analyzed. RESULTS: A total of 118 patients who underwent a total of 192 strictureplasties were well matched to 118 patients who underwent resection. The strictureplasty group exhibited significantly less blood loss (30 ml versus 50 ml, p < 0.001) and stoma creation (2.5% versus 16.9%, p < 0.001). No significant difference was found regarding postoperative complications or length of postoperative stay. At the end of the follow-up, the overall rate of clinical recurrence was 39.4%, and no difference was observed between the two groups. Postoperative prophylactic use of biologics (odds ratio = 0.2, p < 0.001) was the only protective factor against recurrence. CONCLUSION: Strictureplasty does not increase the risk of complications or recurrence compared with resection. It represents a viable alternative to resection in selected patients, and as such, it should have a broader scope of indications and greater acceptance among surgeons.


Assuntos
Doença de Crohn , Humanos , Doença de Crohn/cirurgia , Doença de Crohn/complicações , Recidiva , Reoperação , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Resultado do Tratamento
4.
Zhonghua Zhong Liu Za Zhi ; 46(7): 710-721, 2024 Jul 23.
Artigo em Chinês | MEDLINE | ID: mdl-39034807

RESUMO

In April 2024, the World Health Organization/International Agency for Research on Cancer (IARC) published the global cancer statistics 2022 in the CA: Cancer Journal for Clinicians. This report focuses on the incidence and mortality of 36 cancers in 185 countries or territories worldwide, analyzing the differences of gender, geographic region, and the Human Development Index (HDI) level. It is estimated that in the year 2022, there were 19.96 million new cancer cases and 9.74 million cancer deaths worldwide. Lung cancer (2 480 301, 12.4%) was the most frequently diagnosed cancer in 2022, followed by female breast cancer (2 295 686, 11.5%), colorectal cancer (1 926 118, 9.6%), prostate cancer (1 466 680, 7.3%), and gastric cancer (968 350, 4.9%). Lung cancer (1 817 172, 18.7%) was also the leading cause of cancer death, followed by colorectal cancer (903 859, 9.3%), liver cancer (757 948, 7.8%), female breast cancer (665 684, 6.9%), and gastric cancer (659 853, 6.8%). With demographics-based predictions indicating that the number of new cases of cancer will reach over 35 million by 2050. The Beijing Office for Cancer Prevention and Control team has collated this report and briefly interpreted it in combination with the current situation of cancer incidence and mortality in China.


Assuntos
Saúde Global , Neoplasias Pulmonares , Neoplasias , Neoplasias Gástricas , Humanos , Neoplasias/epidemiologia , Incidência , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/patologia , Neoplasias Pulmonares/epidemiologia , Feminino , Neoplasias Colorretais/epidemiologia , Neoplasias da Mama/epidemiologia , Neoplasias Hepáticas/epidemiologia , Masculino , Neoplasias da Próstata/epidemiologia
5.
Zhonghua Nei Ke Za Zhi ; 63(7): 720-723, 2024 Jul 01.
Artigo em Chinês | MEDLINE | ID: mdl-38951100

RESUMO

A 19-year-old male patient with high-risk acute B-cell lymphoblastic leukemia received haploidentical stem cell transplantation. He developed anemia repeatedly and parvovirus B19 nucleic acid was positive in blood plasma. The patient was diagnosed with cold agglutinin syndrome and multiple organ dysfunction including respiratory failure and hepatitis. In the conflict between viral infection and the treatment of cold agglutinin syndrome, we provided supportive treatment, complement inhibitors to control hemolysis, and antiviral therapy. After timely glucocorticoid and immunosuppressant therapy, the patient had achieved a good response.


Assuntos
Insuficiência de Múltiplos Órgãos , Parvovirus B19 Humano , Humanos , Masculino , Adulto Jovem , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/virologia , Infecções por Parvoviridae/complicações , Infecções por Parvoviridae/diagnóstico , Anemia Hemolítica/etiologia , Anemia Hemolítica/diagnóstico , Anemia Hemolítica Autoimune/terapia
6.
Zhonghua Yi Xue Za Zhi ; 104(6): 433-439, 2024 Feb 06.
Artigo em Chinês | MEDLINE | ID: mdl-38326055

RESUMO

Objective: To investigate the incidence and influencing factors of hypogammaglobulinemia (HGG) in children with steroid-dependent/frequently relapsing nephrotic syndrome (SDNS/FRNS) treated with rituximab (RTX), and its relationship with the risk of severe infections. Methods: The clinical data of children with SDNS/FRNS treated with RTX at the Department of Pediatrics of the First Affiliated Hospital of Zhengzhou University from December 2020 to January 2023 were retrospectively analyzed. RTX treatment was performed using a B-cell-guided regimen (a single dose of 375 mg/m2, a maximum of 500 mg/dose, and an additional one dose when reassessment of peripheral blood CD19+B cells≥1%). Patients were divided into HGG and non-HGG groups according to the presence or absence of HGG during the follow-up period. A multivariate logistic regression model was used to analyze the influencing factors of HGG, and the predictive value of each influencing factor on HGG was assessed by plotting the receiver operating characteristic (ROC) curve. Results: A total of 59 SDNS/FRNS children (48 males and 11 females) were included, and aged [M (Q1, Q3)] 9.4 (6.5, 12.2) years at the time of the first RTX treatment, with a median application of 3 (2, 4) doses of RTX. During the follow-up period of 15.5 (9.9, 22.8) months, the HGG was present in 16 (27.1%) children, of which seven persisted for more than 1 year. Compared with non-HGG group, HGG group had a shorter duration of the disease [3.3 (2.1, 3.6) vs 4.6 (2.4, 8.0) years, P=0.030], younger age at the time of the first RTX treatment [6.2 (5.6, 7.4) vs 11.3 (8.8, 13.3) years, P<0.001], and lower serum IgG levels [5.9 (4.9, 6.4) vs 7.5 (6.1, 8.2) g/L, P<0.001]. Multivariate logistic regression analysis showed that young age at the time of the first RTX treatment (OR=0.52, 95%CI: 0.35-0.78, P=0.002) was an influencing factor of HGG. The area under the curve (AUC) for age at first RTX treatment to predict HGG was 0.887 (95%CI: 0.778-0.955, P<0.001), with an optimal cut-off value of 8.3 years. During the follow-up period, six children (10.2%) developed severe infectious, and there was no statistically significant difference in the incidence of serious infections between the HGG and non-HGG groups [12.5% (2/16) vs 9.3% (4/43), P=1.000]. Conclusions: HGG is frequent in children with SDNS/FRNS treated with RTX, and nearly half of HGG persists for more than 1 year. The possibility of HGG is greater in those≤8.3 years at the first RTX treatment, but HGG does not increase the risk of severe infections in children.


Assuntos
Agamaglobulinemia , Síndrome Nefrótica , Masculino , Feminino , Humanos , Criança , Idoso , Rituximab/uso terapêutico , Síndrome Nefrótica/tratamento farmacológico , Agamaglobulinemia/tratamento farmacológico , Incidência , Estudos Retrospectivos , Esteroides/uso terapêutico , Recidiva , Imunossupressores/uso terapêutico , Resultado do Tratamento
7.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(7): 959-966, 2024 Jul 06.
Artigo em Chinês | MEDLINE | ID: mdl-39034780

RESUMO

Objective: To establish a Plaque-reduction Neutralization Test (PRNT) for the detection of neutralizing antibody titers of Human Respiratory Syncytial Virus (HRSV) and optimize the conditions for preliminary application. Methods: The CHO expression system was used to produce palivizumab monoclonal antibody (palivizumab) and the influencing factors such as cell type, cell culture duration, fixation and permeabilization protocols, and blocking agents. The reproducibility of the method was verified and its correlation was verified with conventional PRNT. Finally, the optimized PRNT assay was further used to determine neutralizing antibody titers against HRSV subtypes A and B in BALB/c mouse serum (immunized by intramuscular injection of HRSV fusion proteins). Results: Palivizumab was expressed at approximately 50 mg/L. The optimal working conditions for PRNT were as follows: culturing HEp-2 cells for 2 days, fixing with 4% (V/V) paraformaldehyde at room temperature for 15 min followed by 0.2% (V/V) Triton X-100 permeabilization for 15 minutes as the optimal fixation-permeabilization and removing the blocking step. The overall coefficient of variation (CV) for the reproducibility validation of this method was <15%, showing a good linear relationship with the conventional PRNT. The Spearman correlation coefficient rs was 0.983. This method was used to detect neutralizing antibody titers in mouse sera against HRSV subtype A strain long and subtype B strain 9320, and the fusion proteins combined with AlOH and CpG adjuvant induced the highest neutralizing antibody titers in mice. Conclusion: The HRSV neutralizing antibody assay established in this study is rapid, reproducible, high-throughput, and can be used to detect neutralizing antibodies to HRSV subtypes A and B.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Camundongos Endogâmicos BALB C , Testes de Neutralização , Vírus Sincicial Respiratório Humano , Animais , Anticorpos Neutralizantes/imunologia , Camundongos , Vírus Sincicial Respiratório Humano/imunologia , Humanos , Testes de Neutralização/métodos , Anticorpos Antivirais/imunologia , Células CHO , Cricetulus , Cricetinae , Palivizumab
8.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(2): 159-165, 2024 Feb 06.
Artigo em Chinês | MEDLINE | ID: mdl-38387944

RESUMO

With the development of information technology and the increasing demand for vaccination services among the people, it is a definite trend to enhance the quality of vaccination services through digitization. This article starts with a clear concept of digital services for vaccination, introduces the current development status in China and abroad, analyzes the advantages and disadvantages of existing models in leading regions, takes a glean from the summation, and proposes targeted solutions. This study suggests establishing a departmental coordination mechanism for data interconnection and sharing, formulating data standards and functional specifications, enhancing the functionalities of the immunization planning information system, strengthening data collection and analytical usage, and intensifying appointment management and science and health education to provide expert guidance for the construction of digital vaccination services across the country in the future.


Assuntos
Imunização , Vacinação , Humanos , Educação em Saúde , China
9.
Zhonghua Wai Ke Za Zhi ; 62(5): 379-386, 2024 May 01.
Artigo em Chinês | MEDLINE | ID: mdl-38548605

RESUMO

Objective: To investigate the risk factors and prognostic value of the textbook outcome (TO) in patients with advanced gastric cancer (AGC) who underwent neoadjuvant chemotherapy followed by surgical resection. Methods: This is a retrospective cohort study. A total of 253 patients with AGC who underwent neoadjuvant chemotherapy combined with gastrectomy and D2 lymphadenectomy in the Department of Gastric Surgery, Fujian Medical University Union Hospital from January 2010 to December 2019 were retrospectively included. There were 195 males and 58 females, aged (60.3±10.0) years (range: 27 to 75 years). The patients were then divided into the TO group (n=168) and the non-TO group (n=85). Multivariate Logistic regression was used to analyze the independent predictors of TO. Univariate and multivariate Cox analysis were used to analyze independent prognosis factors for overall survival (OS) and disease-free survival (DFS). Propensity score matching was performed to balance the TO and non-TO groups, and the Kaplan-Meier method was used to calculate survival rates and draw survival curves. Results: Among the 253 patients, 168 patients (66.4%) achieved TO. The Eastern Cooperative Oncology Group score (OR=0.488, 95%CI: 0.278 to 0.856, P=0.012) and ypN stage (OR=0.626, 95%CI:0.488 to 0.805, P<0.01) were independently predictive of TO. Multivariate analysis revealed that TO was an independent risk factor for both OS (HR=0.662, 95%CI: 0.457 to 0.959,P=0.029) and DFS (HR=0.687, 95%CI: 0.483 to 0.976, P=0.036). After matching, the 5-year OS rate (42.2% vs. 27.8%) and the 5-year DFS rate (37.5% vs. 27.8%) were significantly higher in the TO group than in the non-TO group (both P<0.05). Furthermore, patients in the non-TO group benefited significantly from postoperative chemotherapy (both P<0.05), but those in the TO group did not (both P>0.05). Conclusion: TO is an independent prognosis factor in patients undergoing neoadjuvant chemotherapy and surgery for AGC and is associated with postoperative chemotherapy benefits.


Assuntos
Gastrectomia , Terapia Neoadjuvante , Neoplasias Gástricas , Humanos , Masculino , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/terapia , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Prognóstico , Idoso , Adulto , Taxa de Sobrevida , Excisão de Linfonodo , Intervalo Livre de Doença , Fatores de Risco , Resultado do Tratamento , Quimioterapia Adjuvante , Pontuação de Propensão , Estimativa de Kaplan-Meier , Modelos de Riscos Proporcionais
10.
Phys Rev Lett ; 130(7): 071802, 2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36867815

RESUMO

An absolute measurement of the Λ_{c}^{+} lifetime is reported using Λ_{c}^{+}→pK^{-}π^{+} decays in events reconstructed from data collected by the Belle II experiment at the SuperKEKB asymmetric-energy electron-positron collider. The total integrated luminosity of the data sample, which was collected at center-of-mass energies at or near the ϒ(4S) resonance, is 207.2 fb^{-1}. The result, τ(Λ_{c}^{+})=203.20±0.89±0.77 fs, where the first uncertainty is statistical and the second systematic, is the most precise measurement to date and is consistent with previous determinations.

11.
Phys Rev Lett ; 130(26): 261802, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37450824

RESUMO

We present a search for the lepton flavor violating decays B^{+}→K^{+}τ^{±}ℓ^{∓}, with ℓ=(e,µ), using the full data sample of 772×10^{6} BB[over ¯] pairs recorded by the Belle detector at the KEKB asymmetric-energy e^{+}e^{-} collider. We use events in which one B meson is fully reconstructed in a hadronic decay mode. We find no evidence for B^{±}→K^{±}τℓ decays and set upper limits on their branching fractions at the 90% confidence level in the (1-3)×10^{-5} range. The obtained limits are the world's best results.

12.
Phys Rev Lett ; 131(5): 051804, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37595249

RESUMO

We present the first measurement of the ratio of branching fractions of inclusive semileptonic B-meson decays, R(X_{e/µ})=B(B→Xeν)/B(B→Xµν), a precision test of electron-muon universality, using data corresponding to 189 fb^{-1} from electron-positron collisions collected with the Belle II detector. In events where the partner B meson is fully reconstructed, we use fits to the lepton momentum spectra above 1.3 GeV/c to obtain R(X_{e/µ})=1.007±0.009(stat)±0.019(syst), which is the most precise lepton-universality test of its kind and agrees with the standard-model expectation.

13.
Phys Rev Lett ; 130(18): 181803, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37204890

RESUMO

We search for lepton-flavor-violating τ^{-}→e^{-}α and τ^{-}→µ^{-}α decays, where α is an invisible spin-0 boson. The search uses electron-positron collisions at 10.58 GeV center-of-mass energy with an integrated luminosity of 62.8 fb^{-1}, produced by the SuperKEKB collider and collected with the Belle II detector. We search for an excess in the lepton-energy spectrum of the known τ^{-}→e^{-}ν[over ¯]_{e}ν_{τ} and τ^{-}→µ^{-}ν[over ¯]_{µ}ν_{τ} decays. We report 95% confidence-level upper limits on the branching-fraction ratio B(τ^{-}→e^{-}α)/B(τ^{-}→e^{-}ν[over ¯]_{e}ν_{τ}) in the range (1.1-9.7)×10^{-3} and on B(τ^{-}→µ^{-}α)/B(τ^{-}→µ^{-}ν[over ¯]_{µ}ν_{τ}) in the range (0.7-12.2)×10^{-3} for α masses between 0 and 1.6 GeV/c^{2}. These results provide the most stringent bounds on invisible boson production from τ decays.

14.
Phys Rev Lett ; 130(9): 091902, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36930912

RESUMO

We study the processes e^{+}e^{-}→ωχ_{bJ}(1P) (J=0, 1, or 2) using samples at center-of-mass energies sqrt[s]=10.701, 10.745, and 10.805 GeV, corresponding to 1.6, 9.8, and 4.7 fb^{-1} of integrated luminosity, respectively. These data were collected with the Belle II detector during special operations of the SuperKEKB collider above the ϒ(4S) resonance. We report the first observation of ωχ_{bJ}(1P) signals at sqrt[s]=10.745 GeV. By combining Belle II data with Belle results at sqrt[s]=10.867 GeV, we find energy dependencies of the Born cross sections for e^{+}e^{-}→ωχ_{b1,b2}(1P) to be consistent with the shape of the ϒ(10753) state. These data indicate that the internal structures of the ϒ(10753) and ϒ(10860) states may differ. Including data at sqrt[s]=10.653 GeV, we also search for the bottomonium equivalent of the X(3872) state decaying into ωϒ(1S). No significant signal is observed for masses between 10.45 and 10.65 GeV/c^{2}.

15.
Phys Rev Lett ; 131(21): 211801, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38072600

RESUMO

The first simultaneous determination of the absolute value of the Cabibbo-Kobayashi-Maskawa matrix element V_{ub} using inclusive and exclusive decays is performed with the full Belle data set at the ϒ(4S) resonance, corresponding to an integrated luminosity of 711 fb^{-1}. We analyze collision events in which one B meson is fully reconstructed in hadronic modes. This allows for the reconstruction of the hadronic X_{u} system of the semileptonic b→uℓν[over ¯]_{ℓ} decay. We separate exclusive B→πℓν[over ¯]_{ℓ} decays from other inclusive B→X_{u}ℓν[over ¯]_{ℓ} and backgrounds with a two-dimensional fit that utilizes the number of charged pions in the X_{u} system and the four-momentum transfer q^{2} between the B and X_{u} systems. Combining our measurement with information from lattice QCD and QCD calculations of the inclusive partial rate as well as external experimental information on the shape of the B→πℓν[over ¯]_{ℓ} form factor, we determine |V_{ub}^{excl}|=(3.78±0.23±0.16±0.14)×10^{-3} and |V_{ub}^{incl}|=(3.88±0.20±0.31±0.09)×10^{-3}, respectively, with the uncertainties being the statistical error, systematic errors, and theory errors. The ratio of |V_{ub}^{excl}|/|V_{ub}^{incl}|=0.97±0.12 is compatible with unity.

16.
Phys Rev Lett ; 131(17): 171803, 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37955504

RESUMO

We measure the lifetime of the D_{s}^{+} meson using a data sample of 207 fb^{-1} collected by the Belle II experiment running at the SuperKEKB asymmetric-energy e^{+}e^{-} collider. The lifetime is determined by fitting the decay-time distribution of a sample of 116×10^{3} D_{s}^{+}→ϕπ^{+} decays. Our result is τ_{D_{s}^{+}}=(499.5±1.7±0.9) fs, where the first uncertainty is statistical and the second is systematic. This result is significantly more precise than previous measurements.

17.
Phys Rev Lett ; 131(18): 181801, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37977641

RESUMO

We present the first comprehensive tests of the universality of the light leptons in the angular distributions of semileptonic B^{0}-meson decays to charged spin-1 charmed mesons. We measure five angular-asymmetry observables as functions of the decay recoil that are sensitive to lepton-universality-violating contributions. We use events where one neutral B is fully reconstructed in ϒ(4S)→BB[over ¯] decays in data corresponding to 189 fb^{-1} integrated luminosity from electron-positron collisions collected with the Belle II detector. We find no significant deviation from the standard model expectations.

18.
Phys Rev Lett ; 131(11): 111803, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37774261

RESUMO

We report a measurement of the CP-violating parameters C and S in B^{0}→K_{S}^{0}π^{0} decays at Belle II using a sample of 387×10^{6} BB[over ¯] events recorded in e^{+}e^{-} collisions at a center-of-mass energy corresponding to the ϒ(4S) resonance. These parameters are determined by fitting the proper decay-time distribution of a sample of 415 signal events. We obtain C=-0.04_{-0.15}^{+0.14}±0.05 and S=0.75_{-0.23}^{+0.20}±0.04, where the first uncertainties are statistical and the second are systematic.

19.
Phys Rev Lett ; 130(23): 231801, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37354391

RESUMO

The L_{µ}-L_{τ} extension of the standard model predicts the existence of a lepton-flavor-universality-violating Z^{'} boson that couples only to the heavier lepton families. We search for such a Z^{'} through its invisible decay in the process e^{+}e^{-}→µ^{+}µ^{-}Z^{'}. We use a sample of electron-positron collisions at a center-of-mass energy of 10.58 GeV collected by the Belle II experiment in 2019-2020, corresponding to an integrated luminosity of 79.7 fb^{-1}. We find no excess over the expected standard-model background. We set 90%-confidence-level upper limits on the cross section for this process as well as on the coupling of the model, which ranges from 3×10^{-3} at low Z^{'} masses to 1 at Z^{'} masses of 8 GeV/c^{2}.


Assuntos
Mésons , Humanos , Elétrons
20.
J Dairy Sci ; 106(10): 7147-7163, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37210351

RESUMO

Mastitis is the most common disease of dairy cows that incurs severe economic losses to the dairy industry. Currently, environmental mastitis pathogens are a major problem for most dairy farms. A current commercially available Escherichia coli vaccine does not prevent clinical mastitis and production losses, likely due to antibody accessibility and antigenic variation issues. Therefore, a novel vaccine that prevents clinical disease and production losses is critically needed. Recently a nutritional immunity approach, which restricts bacterial iron uptake by immunologically sequestering conserved iron-binding enterobactin (Ent), has been developed. The objective of this study was to evaluate the immunogenicity of the keyhole limpet hemocyanin-enterobactin (KLH-Ent) conjugate vaccine in dairy cows. Twelve pregnant Holstein dairy cows in their first through third lactations were randomized to the control or vaccine group, with 6 cows per group. The vaccine group received 3 subcutaneous vaccinations of KLH-Ent with adjuvants at drying off (D0), 20 (D21), and 40 (D42) days after drying off. The control group was injected with phosphate-buffered saline (pH 7.4) mixed with the same adjuvants at the same time points. Vaccination effects were assessed over the study period until the end of the first month of lactation. The KLH-Ent vaccine did not cause any systemic adverse reactions or reduction in milk production. Compared with the control group, the vaccine elicited significantly higher levels of serum Ent-specific IgG at calving (C0) and 30 d postcalving (C30), mainly its IgG2 fraction, which was significantly higher at D42, C0, C14, and C30 d, with no significant change in IgG1 levels. Milk Ent-specific IgG and IgG2 levels in the vaccine group were significantly higher on C30. Fecal microbial community structures were similar for both control and vaccine groups on the same day and shifted directionally along the sampling days. In conclusion, the KLH-Ent vaccine successfully triggered strong Ent-specific immune responses in dairy cows without significantly affecting the gut microbiota diversity and health. The results show that Ent conjugate vaccine is a promising nutritional immunity approach in control of E. coli mastitis in dairy cows.


Assuntos
Doenças dos Bovinos , Mastite Bovina , Gravidez , Feminino , Bovinos , Animais , Escherichia coli , Vacinas Conjugadas , Enterobactina , Mastite Bovina/microbiologia , Lactação , Leite/microbiologia , Imunoglobulina G , Ferro
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