Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 97
Filtrar
1.
Pestic Biochem Physiol ; 202: 105953, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38879307

RESUMEN

The brown planthopper (Nilaparvata lugens) is a major destructive rice pest in Asia. High levels of insecticide resistance have been frequently reported, and the G932C mutation in the chitin synthase 1 (CHS1) gene has been found to mediate buprofezin resistance. However, there has been no direct evidence to confirm the functional significance of the single G932C substitution mutation leading to buprofezin resistance in N. lugens. Here, we successfully constructed a knock-in homozygous strain (Nl-G932C) of N. lugens using CRISPR/Cas9 coupled with homology-directed repair (HDR). Compared with the background strain susceptible to buprofezin (Nl-SS), the knock-in strain (Nl-G932C) showed a 94.9-fold resistance to buprofezin. Furthermore, resistant strains (Nl-932C) isolated from the field exhibited a 2078.8-fold resistance to buprofezin, indicating that there are other mechanisms contributing to buprofezin resistance in the field. Inheritance analysis showed that the resistance trait is incomplete dominance. In addition, the Nl-G932C strain had a relative fitness of 0.33 with a substantially decreased survival rate, emergence rate, and fecundity. This study provided in vivo functional evidence for the causality of G932C substitution mutation of CHS1 with buprofezin resistance and valuable information for facilitating the development of resistance management strategies in N. lugens. This is the first example of using CRISPR/Cas9 gene-editing technology in a hemipteran insect to directly confirm the role of a candidate target site mutation in insecticide resistance.


Asunto(s)
Sistemas CRISPR-Cas , Quitina Sintasa , Hemípteros , Resistencia a los Insecticidas , Insecticidas , Tiadiazinas , Animales , Hemípteros/genética , Resistencia a los Insecticidas/genética , Tiadiazinas/farmacología , Quitina Sintasa/genética , Insecticidas/farmacología , Mutación , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Técnicas de Sustitución del Gen , Femenino , Masculino
2.
Vet Sci ; 11(6)2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38922018

RESUMEN

Ischemic teat necrosis (ITN) is a growing problem in the dairy industry characterized by teat lesions, necrosis, pruritus and automutilation. Despite the economic and welfare consequences, there is no treatment, and the etiology of the disease remains poorly understood. The aim of this study was to investigate ITN by analyzing its clinical presentation, potential risk factors and microbial involvement. Methods included collection of milk and swab samples from affected cows over a period of one-and-a-half years and completion of questionnaires by veterinarians and farmers. Microbial testing included PCR testing for Treponema spp. and cultural testing by anaerobic and aerobic incubation on blood agar. The results showed a high and significant prevalence of Treponema spp. and Staphylococcus aureus in affected teats compared to non-ITN-affected control teats, indicating their potential role in the development of ITN. Other factors such as edema and milking practices also appear to contribute to the tissue damage. First-lactation and early-lactation heifers are particularly at risk. In conclusion, ITN appears to have a multifactorial etiology with both infectious and non-infectious factors playing a role. Further research is needed to better understand the complex interplay of these factors and to develop effective prevention and management strategies.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38833401

RESUMEN

Superpixel aggregation is a powerful tool for automated neuron segmentation from electron microscopy (EM) volume. However, existing graph partitioning methods for superpixel aggregation still involve two separate stages-model estimation and model solving, and therefore model error is inherent. To address this issue, we integrate the two stages and propose an end-to-end aggregation framework based on deep learning of the minimum cost multicut problem called DeepMulticut. The core challenge lies in differentiating the NPhard multicut problem, whose constraint number is exponential in the problem size. With this in mind, we resort to relaxing the combinatorial solver-the greedy additive edge contraction (GAEC)-to a continuous Soft-GAEC algorithm, whose limit is shown to be the vanilla GAEC. Such relaxation thus allows the DeepMulticut to integrate edge cost estimators, Edge-CNNs, into a differentiable multicut optimization system and allows a decision-oriented loss to feed decision quality back to the Edge-CNNs for adaptive discriminative feature learning. Hence, the model estimators, Edge-CNNs, can be trained to improve partitioning decisions directly while beyond the NP-hardness. Also, we explain the rationale behind the DeepMulticut framework from the perspective of bi-level optimization. Extensive experiments on three public EM datasets demonstrate the effectiveness of the proposed DeepMulticut.

4.
Orthop Surg ; 16(7): 1657-1664, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38790115

RESUMEN

OBJECTIVE: Both porous metal cones and metaphyseal sleeves are excellent implants for reconstructing severe bone defects in the knee joint, but they both exhibit design limitations. The porous metal cone, especially, has significant room for improvement in its shape design. The existing porous metal cones often feature a conical external surface with a relatively small taper, potentially compromising both rotational and axial stability. To improve both axial and rotational stability in porous metal cones, we developed a 3D-printed stepped porous metal cone. This study aimed to assess the short-term clinical outcome of the 3D-printed stepped porous metal cone and to compare it with the clinical outcome of patients who underwent revision total knee arthroplasty (rTKA) with the metaphyseal sleeves during the same period. METHOD: Patients who underwent total knee arthroplasty revision with metaphyseal bone defect reconstruction from 2019 to 2021 were retrospectively analyzed. A total of 61 patients were enrolled in the study, including 15 patients using 3D-printed stepped porous metal cones and 46 patients using metaphyseal metal sleeves. Thirty patients using metaphyseal sleeves were screened by propensity score matching method and compared with those using stepped cones. Analysis included the American Knee Society Score, the Hospital for Special Surgery knee score, the Western Ontario and McMaster Universities Arthritis index, the Short Form 12 (SF-12) health survey, and radiographic assessment with a mean follow-up of 28.5 ± 8.3 months. To conduct comparative analyses, unpaired Student's t-tests were employed for continuous variables, while categorical variables were analyzed using the appropriate Fisher exact or chi-squared test. RESULTS: In this study, the survival rates of both the stepped cone and metaphyseal sleeve were 100%. There was no statistically significant difference in postoperative knee function scores between the two groups (p > 0.05). However, patients in the cone group had significantly higher mental component summary scores on the SF-12 scale (p < 0.05) and higher increases in mean postoperative physical component summary scores than patients in the sleeve group (p < 0.05). In addition, patients in the cone group experienced fewer intraoperative and postoperative complications compared to the sleeve group. CONCLUSION: The 3D-printed stepped porous metal cone can effectively reconstruct bone defects in complex rTKA and provide satisfactory early clinical and radiographic results. The 3D-printed stepped cone provides a more stable structure similar to the sleeve while maintaining the original benefits of the cone making it a promising choice for rTKA.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Prótesis de la Rodilla , Impresión Tridimensional , Diseño de Prótesis , Humanos , Femenino , Masculino , Anciano , Estudios Retrospectivos , Artroplastia de Reemplazo de Rodilla/métodos , Persona de Mediana Edad , Porosidad , Reoperación/métodos
5.
Pathogens ; 13(5)2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38787282

RESUMEN

Prevention of new intramammary infection (NIMI) during the dry period (DP) is essential to prevent the development of mastitis in dairy cows. To investigate risk factors for NIMI, 212 cows, comprising a total of 848 udder quarters, were examined in this study. Quarter milk samples were taken on the day of drying off and 7 ± 3 days after calving. Cow- and quarter-level associated risk factors were assessed at the beginning of the DP and after calving. In total, 7.1% of the udder quarters developed an NIMI between the samplings. Non-aureus staphylococci (40.4%) and Gram-negative pathogens (22.8%) were most frequently the cause of NIMI. The observed milk leakage prevalence was 16.7%, with a peak 24 h after drying off. Simultaneously, the udder pressure peaked 24 h after drying off. A significant correlation between milk yield on the day before drying off and milk leakage could be proven. Cows with quarters leaking milk produced an average milk yield of 28.32 kg on the day before drying off. Generalised linear mixed models and odds ratios were calculated to determine the significant risk factors for NIMI during the DP and early lactation. Quarters leaking milk had 3.4 higher odds for NIMI between the samplings compared to quarters without milk leakage. Quarters from cows with dirty udders had 3.1 higher odds of developing an NIMI between the samplings compared to quarters from cows with clean udders. The results of this study demonstrate the importance of dry cow management before drying off and during the critical period of active involution of the udder tissue.

6.
Microb Cell Fact ; 23(1): 119, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38659027

RESUMEN

BACKGROUND: Clostridium spp. has demonstrated therapeutic potential in cancer treatment through intravenous or intratumoral administration. This approach has expanded to include non-pathogenic clostridia for the treatment of various diseases, underscoring the innovative concept of oral-spore vaccination using clostridia. Recent advancements in the field of synthetic biology have significantly enhanced the development of Clostridium-based bio-therapeutics. These advancements are particularly notable in the areas of efficient protein overexpression and secretion, which are crucial for the feasibility of oral vaccination strategies. Here, we present two examples of genetically engineered Clostridium candidates: one as an oral cancer vaccine and the other as an antiviral oral vaccine against SARS-CoV-2. RESULTS: Using five validated promoters and a signal peptide derived from Clostridium sporogenes, a series of full-length NY-ESO-1/CTAG1, a promising cancer vaccine candidate, expression vectors were constructed and transformed into C. sporogenes and Clostridium butyricum. Western blotting analysis confirmed efficient expression and secretion of NY-ESO-1 in clostridia, with specific promoters leading to enhanced detection signals. Additionally, the fusion of a reported bacterial adjuvant to NY-ESO-1 for improved immune recognition led to the cloning difficulties in E. coli. The use of an AUU start codon successfully mitigated potential toxicity issues in E. coli, enabling the secretion of recombinant proteins in C. sporogenes and C. butyricum. We further demonstrate the successful replacement of PyrE loci with high-expression cassettes carrying NY-ESO-1 and adjuvant-fused NY-ESO-1, achieving plasmid-free clostridia capable of secreting the antigens. Lastly, the study successfully extends its multiplex genetic manipulations to engineer clostridia for the secretion of SARS-CoV-2-related Spike_S1 antigens. CONCLUSIONS: This study successfully demonstrated that C. butyricum and C. sporogenes can produce the two recombinant antigen proteins (NY-ESO-1 and SARS-CoV-2-related Spike_S1 antigens) through genetic manipulations, utilizing the AUU start codon. This approach overcomes challenges in cloning difficult proteins in E. coli. These findings underscore the feasibility of harnessing commensal clostridia for antigen protein secretion, emphasizing the applicability of non-canonical translation initiation across diverse species with broad implications for medical or industrial biotechnology.


Asunto(s)
Clostridium butyricum , Clostridium , Proteínas Recombinantes , Clostridium butyricum/genética , Clostridium butyricum/metabolismo , Clostridium/genética , Clostridium/metabolismo , Humanos , Proteínas Recombinantes/genética , Antígenos de Neoplasias/inmunología , Antígenos de Neoplasias/genética , Vacunas contra el Cáncer/inmunología , Vacunas contra el Cáncer/genética , SARS-CoV-2/inmunología , SARS-CoV-2/genética , Administración Oral , Proteínas de la Membrana/genética , Proteínas de la Membrana/inmunología , Proteínas de la Membrana/metabolismo , Esporas Bacterianas/genética , Esporas Bacterianas/inmunología , Vacunación , COVID-19/prevención & control , Ingeniería Genética , Escherichia coli/genética , Escherichia coli/metabolismo , Regiones Promotoras Genéticas
7.
ACS Appl Mater Interfaces ; 16(3): 4003-4012, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38207002

RESUMEN

N-Spirocyclic cations have excellent alkali resistance stability, and precise design of the structure of N-spirocyclic anion-exchange membranes (AEMs) improves their comprehensive performance. Here, we design and synthesize high-performance poly(triphenylene piperidine) membranes based on the "fishbone" design of amino/N-spirocyclic cations. The "fishbone" design does not disrupt the overall stabilized conformation but promotes a microphase separation structure, while exerting the synergistic effect of piperidine cations and spirocyclic cations, resulting in a membrane with good conductivity and alkali resistance stability. The hydroxide conductivity of the QPTPip-ASU-X membrane reached up to 133.5 mS cm-1 at 80 °C. The QPTPip-ASU-15 membrane was immersed in a 2 M NaOH solution at 80 °C for 1200 h, and the conductivity was maintained at 91.02%. In addition, the QPTPip-ASU-5 membrane had the highest peak power density of 255 mW cm-2.

8.
Plants (Basel) ; 12(23)2023 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-38068696

RESUMEN

Penoxsulam is an acetolactate synthase (ALS)-inhibiting herbicide usually applied by post-emergence foliar spraying (PFS) for the control of Echinochloa crus-galli and numerous annual weeds in paddy fields. Herbicides applied by foliar spraying can have negative impacts on the environment, ecosystems, and human health. In this study, the response of E. crus-galli and rice to the PFS and post-emergence water-dispersal (PWD) applications of penoxsulam, and the differences in the detoxification displayed by them between the two treatment methods were compared. The results showed that the PWD application of penoxsulam provides a similar control efficacy against E. crus-galli as PFS at the 1-, 3-, and 5-leaf stages. Meanwhile, the PWD application had a higher safety for the rice. After being treated with 30 g a.i. ha-1 penoxsulam, residues were not detected in the rice treated by the PWD application method, whereas, with the PFS treatment, there was 59.0 µg/kg penoxsulam remaining. With the PFS application, there were many more residues of penoxsulam in the E. crus-galli than with the PWD method; the amount of residues was 32-fold higher 12 h after treatment. The in vitro enzyme activity assays revealed that the activities of ALS, glutathione-S-transferase (GST), and cytochrome P450 monooxygenases (P450) were increased in the PWD treatments, and were 1.5-, 1.3-, and 2.3-fold higher than with PFS 72 h after treatment. The real-time quantitative PCR (qRT-PCR) revealed that the GST1 and P450 genes, CYP81A14, CYP81A12, CYP81A18, and CYP81A21 were upregulated with the PWD application versus PFS in the E. crus-galli. In summary, these results demonstrate that the herbicidal activity was not affected by the upregulation of target and metabolic enzyme activities with the PWD application of penoxsulam. This research could contribute to application strategies reducing the risk of rice injury and environmental impacts by using water-dispersal formulations of penoxsulam.

9.
Microbiol Spectr ; 11(6): e0245923, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-37947521

RESUMEN

IMPORTANCE: Continued efforts in developing the CRISPR-Cas systems will further enhance our understanding and utilization of Clostridium species. This study demonstrates the development and application of a genome-engineering tool in two Clostridium strains, Clostridium butyricum and Clostridium sporogenes, which have promising potential as probiotics and oncolytic agents. Particular attention was given to the folding of precursor crRNA and the role of this process in off-target DNA cleavage by Cas12a. The results provide the guidelines necessary for efficient genome engineering using this system in clostridia. Our findings not only expand our fundamental understanding of genome-engineering tools in clostridia but also improve this technology to allow use of its full potential in a plethora of biotechnological applications.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Edición Génica/métodos , Clostridium/genética , Bacterias Anaerobias/genética , Genoma Bacteriano
10.
Front Immunol ; 14: 1241632, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37869009

RESUMEN

Despite considerable clinical success, the potential of cancer immunotherapy is restricted by a lack of tumour-targeting strategies. Treatment requires systemic delivery of cytokines or antibodies at high levels to achieve clinically effective doses at malignant sites. This is exacerbated by poor penetration of tumour tissue by therapeutic antibodies. High-grade immune-related adverse events (irAEs) occur in a significant number of patients (5-15%, cancer- and therapeutic-dependent) that can lead to lifelong issues and can exclude from treatment patients with pre-existing autoimmune diseases. Tumour-homing bacteria, genetically engineered to produce therapeutics, is one of the approaches that seeks to mitigate these drawbacks. The ability of Clostridium sporogenes to form spores that are unable to germinate in the presence of oxygen (typical of healthy tissue) offers a unique advantage over other vectors. However, the limited utility of existing gene editing tools hinders the development of therapeutic strains. To overcome the limitations of previous systems, expression of the Cas9 protein and the gRNA was controlled using tetracycline inducible promoters. Furthermore, the components of the system were divided across two plasmids, improving the efficiency of cloning and conjugation. Genome integrated therapeutic genes were assayed biochemically and in cell-based functional assays. The potency of these strains was further improved through rationally-conceived gene knock-outs. The new system was validated by demonstrating the efficient addition and deletion of large sequences from the genome. This included the creation of recombinant strains expressing two pro-inflammatory cytokines, interleukin-2 (IL-2) and granulocyte macrophage-colony stimulating factor (GM-CSF), and a pro-drug converting enzyme (PCE). A comparative, temporal in vitro analysis of the integrant strains and their plasmid-based equivalents revealed a substantial reduction of cytokine activity in chromosome-based constructs. To compensate for this loss, a 7.6 kb operon of proteolytic genes was deleted from the genome. The resultant knock-out strains showed an 8- to 10-fold increase in cytokine activity compared to parental strains.


Asunto(s)
Edición Génica , Neoplasias , Humanos , Sistemas CRISPR-Cas , Neoplasias/genética , Citocinas/genética
11.
Orthop Surg ; 15(12): 3202-3208, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37873568

RESUMEN

OBJECTIVE: Management of bone loss in complex primary and revision total knee arthroplasty is key to the surgeries. Metaphyseal metal sleeves have been increasingly used recently to reconstruct severe knee metaphyseal bone defects. This study aimed to investigate the outcomes of the metaphyseal sleeve reconstructing Anderson Orthopedic Research Institute (AORI) type II and type III bone defects of knee joint. METHODS: From 2014 to 2019, a total of 44 knees were enrolled in this clinical retrospective study after the screening, including seven cases of primary TKA and 37 cases of revision TKA. The types of bone defects involved in this study were AORI types II and III, and did not involve AORI type I bone defects. Patients' knee function preoperatively and postoperatively as well as quality of life were recorded and analyzed. Analysis included the American Knee Society Score (KSS), hospital for special surgery knee score (HSS), the Western Ontario and McMaster Universities (WOMAC) index, the Short Form 12 (SF-12) health survey, visual analogue scale score, and radiographic assessment with a mean follow-up of 6.4 years. Paired t-tests were used to determine the significance of changes in clinical scores and knee mobility. RESULTS: A mean follow-up of 77.2 (±17.6, standard deviation [SD]) months was performed, and none of the patients underwent knee revision for infection or aseptic loosening. At the last follow-up, the KSS knee score changed statistically from 37.1 (±19.7) preoperatively to 86.5 (±13.6, SD, p < 0.001) postoperatively and the KSS function score from 32.7 (±24.0) preoperatively to 78.3 (±15.6, SD, p < 0.001) postoperatively. The knee mobility improved from a mean of preoperative 72.61° (±33.42°, SD) to 108.52° (±24.15°, SD, p < 0.001). Postoperative radiographs showed that the host bone was tightly integrated with the metaphyseal metal sleeve, and there was no obvious translucent line formation around the sleeve. Of the patients, 86.4% had a postoperative satisfaction score ≥8 (10-point scale). CONCLUSION: At the mean follow-up of 6.4 years, the survival rate of the metaphyseal sleeves was 100%. Metaphyseal sleeves combined with cementless stems is an excellent and viable option for reconstruction of AORI type II and type III bone defects of the knee.


Asunto(s)
Prótesis de la Rodilla , Humanos , Estudios de Seguimiento , Estudios Retrospectivos , Calidad de Vida , Tasa de Supervivencia , Reoperación , Diseño de Prótesis , Articulación de la Rodilla/cirugía , Rótula , Metales
12.
Br J Cancer ; 129(10): 1679-1691, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37731021

RESUMEN

BACKGROUND: NME1 has been exploited as a potential translational target for decades. Substantial efforts have been made to upregulate the expression of NME1 and restore its anti-metastasis function in metastatic cancer. METHODS: Cycloheximide (CHX) chase assay was used to measure the steady-state protein stability of NME1 and HSP90α. The NME1-associating proteins were identified by immunoprecipitation combined with mass spectrometric analysis. Gene knockdown and overexpression were employed to examine the impact of HSP90AA1 on intracellular NME1 degradation. The motility and invasiveness of breast cancer cells were examined in vitro using wound healing and transwell invasion assays. The orthotopic spontaneous metastasis and intra-venous experimental metastasis assays were used to test the formation of metastasis in vivo, respectively. RESULTS: HSP90α interacts with NME1 and increases NME1 lifetime by impeding its ubiquitin-proteasome-mediated degradation. HSP90α overexpression significantly inhibits the metastatic potential of breast cancer cells in vitro and in vivo. A novel cell-permeable peptide, OPT22 successfully mimics the HSP90α function and prolongs the life span of endogenous NME1, resulting in reduced metastasis of breast cancer. CONCLUSION: These results not only reveal a new mechanism of NME1 degradation but also pave the way for the development of new and effective approaches to metastatic cancer therapy.


Asunto(s)
Neoplasias de la Mama , Proteínas de Choque Térmico , Humanos , Femenino , Proteínas de Choque Térmico/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Procesamiento Proteico-Postraduccional , Proteínas HSP90 de Choque Térmico/metabolismo , Metástasis de la Neoplasia , Nucleósido Difosfato Quinasas NM23/genética
13.
Ying Yong Sheng Tai Xue Bao ; 34(7): 1763-1770, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37694459

RESUMEN

To investigate the effects of algal detritus export on the trophic structure of macrozoobenthic community in the adjacent benthic habitat during the bloom and decline of macroalgae, we collected macrozoobenthos from the adjacent sea area of Dalian Island in the North Yellow Sea in May (the algal bloom period) and August (the algal decay period) of 2020. We quantifyied the seasonal changes in the trophic structure of macrozoobenthic community by using carbon and nitrogen stable isotope techniques. Results showed that δ13C and δ15N values of macrozoo-benthos in May ranged from -23.14‰ to -14.24‰, 6.21‰ to 12.90‰, respectively, and -22.36‰ to -14.13‰, 5.33‰ to 12.00‰, respectively in August. Results of PERMANOVA analysis showed that δ13C values of macrozoobenthos differed significantly between the two months, while δ15N values were not significantly different. Based on the Euclidean distance, the macrozoobenthic communities in both months could be classified into five trophic functional groups. The trophic levels of macrozoobenthos ranged from 2.00 (Nitidotellina minuta) to 3.97 (Glycera onomichiensis) in May and from 2.00 (N. minuta) to 3.96 (G. onomichiensis) in August. The δ13C range, δ15N range, mean centroid distance, total area and corrected standard ellipse areas which represented community trophic structure indices in August were higher than those in May. Our results indicated that the trophic diversity level and trophic niche width of the macrozoobenthic community in the adjacent sea area of the seaweed bed were higher in the algal decline season.


Asunto(s)
Algas Marinas , Verduras , Estaciones del Año , Carbono , Isótopos de Nitrógeno , China
14.
Pathogens ; 12(9)2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37764906

RESUMEN

The aim of this cross-sectional study was to investigate associated factors of the severity of clinical mastitis (CM). Milk samples of 249 cases of CM were microbiologically examined, of which 27.2% were mild, 38.5% moderate, and 34.3% severe mastitis. The samples were incubated aerobically and anaerobically to investigate the role of aerobic and anaerobic microorganisms. In addition, the pathogen shedding was quantitatively examined, and animal individual data, outside temperature and relative humidity, were collected to determine associated factors for the severity of CM. The pathogen isolated the most was Escherichia coli (35.2%), followed by Streptococcus spp. (16.4%). Non-aureus staphylococci (NaS) (15.4%) and other pathogens (e.g., Staphylococcus aureus, coryneforms) (15.4%) were the pathogens that were isolated the most for mild mastitis. Moderate mastitis was mostly caused by E. coli (38%). E. coli was also the most common pathogen in severe mastitis (50.6%), followed by Streptococcus spp. (16.4%), and Klebsiella spp. (10.3%). Obligate anaerobes (Clostridium spp.) were isolated in one case (0.4%) of moderate mastitis. The mortality rate (deceased or culled due to the mastitis in the following two weeks) was 34.5% for severe mastitis, 21.7% for moderate mastitis, and 4.4% for mild mastitis. The overall mortality rate of CM was 21.1%. The pathogen shedding (back logarithmized) was highest for severe mastitis (55,000 cfu/mL) and E. coli (91,200 cfu/mL). High pathogen shedding, low previous somatic cell count (SCC) before mastitis, high outside temperature, and high humidity were associated with severe courses of mastitis.

15.
iScience ; 26(8): 107484, 2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37599836

RESUMEN

Reported herein is a new set of vectors designed to streamline molecular cloning and genome editing by exploiting modern cloning methods. The new vectors build on the existing pMTL8000 vectors that have been a staple of Clostridium research for more than a decade. The introduction of two pairs of type IIS restriction sites flanking an insulated multiple cloning site in both a cloning vector and a CRISPR-Cas9 gene editing vector enables plasmid construction in a "one-pot" reaction, avoiding the more laborious steps of conventional cloning. A synthetic lacZα expression cassette introduced between the cloning sites enables visual detection of background colonies. In addition, distinct selection markers on each vector permit selection of the desired clones according to antibiotic resistance. An example of strain development using the new vectors is demonstrated.

16.
Sci Total Environ ; 902: 166038, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37562632

RESUMEN

Petroleum hydrocarbons are widespread in seawater. As an important sea area in northern China, the content and distribution of petroleum hydrocarbons in seawater need our attention because of the high toxicity and lasting polluting effects on the ecological environment of the Yellow Sea and Bohai Sea. In addition, there are few reports comparing the diversity of oil-degrading bacteria before and after enrichment. Therefore, we collected surface seawater from 10 sites in the Yellow Sea and Bohai Sea in the autumn of 2020 to study the distribution characteristics of total petroleum hydrocarbons (TPH) and the diversity of oil-degrading bacteria. The concentration of TPH was 81.65 µg/L-139.55 µg/L at ten sites in the Bohai Sea and the Yellow Sea, which conformed to the China Grade II water quality standard (GB3097-1997). Moreover, the pristine/phytane (PR/PH) value of most sites was close to 1, indicating that the area was obviously polluted by exogenous petroleum hydrocarbons. We found that oil-degrading bacteria in the seawater of the Yellow Sea and the Bohai Sea had a good degradation effect on C11-C14 short chain alkanes (degradation rate of 59.19-73.22 %) and C1-C4 phenanthrene (degradation rate of 48.19-60.74 %). In terms of the diversity of oil-degrading bacteria, Gammaproteobacteria and Alphaproteobacteria dominated the enriched bacterial communities. Notably, the relative abundance of Alcanivorax changed significantly before and after enrichment. We proposed that surface seawater in the Bohai Sea and Yellow Sea could form oil-degrading bacteria mainly composed of Alcanivorax, which had great potential for oil pollution remediation.


Asunto(s)
Contaminación por Petróleo , Petróleo , Agua de Mar/química , Hidrocarburos/metabolismo , Alcanos/metabolismo , Bacterias/metabolismo , Petróleo/análisis , China , Biodegradación Ambiental
17.
Phys Rev E ; 108(1-1): 014208, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37583229

RESUMEN

We investigate matter-wave solitons in a binary Bose-Einstein condensate (BEC) with spin-orbit (SO) coupling, loaded in a one-dimensional (1D) deep optical lattice and a three-dimensional anisotropic magnetic trap, which creates an array of elongated sub-BECs with transverse tunneling. We show that the system supports 1D continuous and discrete solitons localized in the longitudinal (along the array) and the transverse (across the array) directions, respectively. In addition, such solitons are always unpolarized in the zero-momentum state but polarized in finite-momentum states. We also show that the system supports stable two-dimensional semidiscrete solitons, including single- and multiple-peaked ones, localized in both the longitudinal and transverse directions. Stability diagrams for single-peaked semidiscrete solitons in different parameter spaces are identified. The results reported here are beneficial not only for understanding the physical property of SO-coupled BECs but also for generating new types of matter-wave solitons.

18.
Micromachines (Basel) ; 14(7)2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37512672

RESUMEN

Object-space model optimization (OSMO) has been proven to be a simple and high-accuracy approach for additive manufacturing of tomographic reconstructions compared with other approaches. In this paper, an improved OSMO algorithm is proposed in the context of OSMO. In addition to the two model optimization steps in each iteration of OSMO, another two steps are introduced: one step enhances the target regions' in-part edges of the intermediate model, and the other step weakens the target regions' out-of-part edges of the intermediate model to further improve the reconstruction accuracy of the target boundary. Accordingly, a new quality metric for volumetric printing, named 'Edge Error', is defined. Finally, reconstructions on diverse exemplary geometries show that all the quality metrics, such as VER, PW, IPDR, and Edge Error, of the new algorithm are significantly improved; thus, this improved OSMO approach achieves better performance in convergence and accuracy compared with OSMO.

19.
Microorganisms ; 11(7)2023 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-37512812

RESUMEN

The aim of this cross-sectional study was to investigate the occurrence of bacteremia in severe mastitis cases of dairy cows. Milk and corresponding blood samples of 77 cases of severe mastitis were bacteriologically examined. All samples (milk and blood) were incubated aerobically and anaerobically to also investigate the role of obligate anaerobic microorganisms in addition to aerobic microorganisms in severe mastitis. Bacteremia occurred if identical bacterial strains were isolated from milk and blood samples of the same case. In addition, pathogen shedding was examined, and the data of animals and weather were collected to determine associated factors for the occurrence of bacteremia in severe mastitis. If Gram-negative bacteria were detected in milk samples, a Limulus test (detection of endotoxins) was also performed for corresponding blood samples without the growth of Gram-negative bacteria. In 74 cases (96.1%), microbial growth was detected in aerobically incubated milk samples. The most-frequently isolated bacteria in milk samples were Escherichia (E.) coli (48.9%), Streptococcus (S.) spp. (18.1%), and Klebsiella (K.) spp. (16%). Obligatory anaerobic microorganisms were not isolated. In 72 cases (93.5%) of the aerobically examined blood samples, microbial growth was detected. The most-frequently isolated pathogens in blood samples were non-aureus Staphylococci (NaS) (40.6%) and Bacillus spp. (12.3%). The Limulus test was positive for 60.5% of cases, which means a detection of endotoxins in most blood samples without the growth of Gram-negative bacteria. Bacteremia was confirmed in 12 cases (15.5%) for K. pneumoniae (5/12), E. coli (4/12), S. dysgalactiae (2/12), and S. uberis (1/12). The mortality rate (deceased or culled) was 66.6% for cases with bacteremia and 34.1% for cases without bacteremia. High pathogen shedding and high humidity were associated with the occurrence of bacteremia in severe mastitis.

20.
Transpl Immunol ; 80: 101881, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37392897

RESUMEN

Post-transplant lymphoproliferative disease (PTLD) is a rare complication accompanying organ transplantation. Herein, we presented 3 cases of PTLD with different primary sites. All three patients presented with symptoms in the corresponding organs or sites and the latter two patients started with atypical symptoms of infections. The first two patients who developed the disease about a year after liver transplantation both had EBV infections. All three patients received immunosuppressant reduction and antiviral therapy. In case 2, remission occurred midway. Adult liver transplantation recipients are at high risk for PTLD, and screening for EBV infection should be intensified in such recipients within 1 year after liver transplantation. Patients should be highly alert for the development of PTLD when new unidentified masses appear, for whom enhanced CT and tissue biopsy should be performed as early as possible.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Trasplante de Hígado , Trastornos Linfoproliferativos , Trasplante de Órganos , Humanos , Adulto , Trasplante de Hígado/efectos adversos , Infecciones por Virus de Epstein-Barr/diagnóstico , Trastornos Linfoproliferativos/diagnóstico , Trastornos Linfoproliferativos/etiología , Trastornos Linfoproliferativos/terapia , Inmunosupresores/uso terapéutico
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...