Predictive models for metritis cure using farm-collected data, metabolic and inflammation biomarkers, and hemogram variables measured at diagnosis

Our objective was to evaluate the accuracy of predictive models for metritis spontaneous cure (SC) and cure among ceftiofur-treated cows using farm collected data only, and with the addition of hemogram variables and circulating concentration of metabolites, minerals, and biomarkers of inflammation measured at time of diagnosis. Data related to parity, calving related issues, body condition score (BCS), rectal temperature (RT), and days in milk (DIM) at metritis diagnosis were collected from a randomized clinical trial that included 412 metritic cows from 4 herds in TX, CA, and FL. Metritis was defined as the presence of red-brownish, watery, and fetid vaginal discharge, while cure was defined as the absence of metritis 14 d after initial diagnosis. Cows were randomly allocated to receive systemic ceftiofur therapy (2 subcutaneous doses of 6.6 mg/kg of ceftiofur crystalline-free acid on the day of diagnosis and 3 d later; CEF) or to remain untreated (CON). At enrollment (day of metritis diagnosis), blood samples were collected and submitted to cell blood count (CBC) and processed for the measurement of 13 minerals and biomarkers of metabolism and inflammation (BM). Univariable analysis to evaluate the association of farm collected data and blood assessed variables with metritis cure were performed, and variables with P ≤ 0.20 were offered to multivariable logistic regression models and retained if P ≤ 0.15. The area under the curve (AUC) for models predicting SC using farm data only and farm + BM, was 0.70 and 0.76 respectively. Cell blood count variables were not retained in the models for SC. For models predicting cure among CEF cows, the AUC was 0.75, 0.77, 0.80, and 0.80 for models using farm data only, farm + CBC, farm + BM, and farm + CBC + BM, respectively. Predictive models of metritis cure had fair accuracy, with SC models being less accurate than models predictive of cure among CEF cows. Additionally, adding BM variables marginally improved the accuracy of models using farm collected data, while CBC data did not improve the accuracy of predictive models.

Azide-Masked Resiquimod Activated by Hypoxia for Selective Tumor Therapy

Resiquimod (R848) is an immunomodulator causing a severe systemic inflammatory reaction due to low tumor selectivity, thus hindering its use in cancer therapy. Therefore, an azide-masked prodrug (R848-N₃ ) of R848 was developed, which was selectively activated to R848 in hypoxic tumors. R848-N₃ significantly reduces pro-inflammatory cytokines in treated mice to 1/12 compared to R848 at the same dose. In addition, combretastatin A4 nanoparticles (CA4-NPs) were used to enhance the tumor selectivity of R848-N₃ by elevating the level of tumor hypoxia. R848-N₃ +CA4-NPs had higher tumor selectivity than the intratumoral injection of R848 at 1 h after administration. The concentration of the active R848 in the tumor was 21.45-fold that in the heart. Benefiting from the high tumor selectivity of R848-N₃ , R848-N₃ +CA4-NPs+anti-PD1 exerted 94.1% tumor suppression and 40.0% tumor cure. Therefore, this work highlighted the potential of azide-masking strategy in the development of tumor-selective prodrugs with reduced toxicity. This article is protected by copyright. All rights reserved.

Ferri-Liposomes: Preformulation and Selective Cytotoxicity against A549 Lung Cancer Cells

Liposomes have become successful nanostructured systems used in clinical practices. These vesicles are able to carry important drug loadings with noteworthy stability. The aim of this work was to develop iron oxide-loaded stealth liposomes as a prospective alternative for the treatment of lung cancer. In this study, citric acid iron oxide nanoparticles (IONPs-Ac) were synthesized and encapsulated in stealth liposomes. Their cytotoxicity and selectivity against lung tumor cells were assessed. Stealth liposomal vesicles, with relevant content of IONPs-Ac, named ferri-liposomes (SL-IONPs-Ac), were produced with an average size of 200 nm. They displayed important cytotoxicity in a human lung cancer cells model (A549 cells), even at low concentrations, whereas free IONPs-Ac displayed adequate biocompatibility. Nevertheless, the treatment at the same concentration of ferri-liposomes against HEK-293 cells, a normal human cell lineage, was not significantly cytotoxic, revealing a probable lung tumor selectiveness of the fabricated formulation. Furthermore, from the flow cytometry studies, it was possible to infer that ferri-liposomes were able to induce A549 tumor cells death through apoptosis/ferroptosis processes, evidenced by a significant reduction of the mitochondrial membrane potential.

Implementation of a targeted mastitis therapy concept using an on-farm rapid test: antimicrobial consumption, cure rates and compliance

BACKGROUND

Aim of the present study was to investigate the implementation of a targeted therapy (tLCT) concept under real-life circumstances, taking both pathogen-related and animal-related factors into account. The reduction of antibiotics without negative effects on cure rates was evaluated as well as the compliance by the farmers.

METHODS

After analysing the existing conventional therapy (CT) concepts of five farms, the tLCT concept and a novel on-farm test were introduced. Three treatment groups were compared with respect to bacteriological cure (BC), cytological cure (CYC), full cure (FC), new infection rate (NIR), relapse rate and the treatment approach per mastitis case: the CT group, the tLCT group including all clinical mastitis (CM) cases treated according to the concept, and the modified tLCT group (tLCTmod), including the CM cases in which farmers deviated from the concept.

RESULTS

Even so farmers deviated from the treatment concept in 506 out of 909 cases; belonging to one of the three treatment groups had no significant impact on BC, CYC, FC, NIR or relapse rate. The antibiotic usage in the tLCT as well as in the tLCTmod group was significantly lower in comparison to the CT group.

CONCLUSION

From this, it can be deduced that farmers will reduce antibiotic doses by implementing a tLCT concept.

The association of cow-related factors assessed at metritis diagnosis with metritis cure risk, reproductive performance, milk yield, and culling for untreated and ceftiofur-treated dairy cows

Our objective was to assess the association of cow-related factors with metritis cure risk and economically important outcomes. In this prospective cohort study nested inside a randomized clinical trial, cows enrolled in a clinical trial that aimed to evaluate an alternative metritis therapy that had available plasma samples collected at metritis diagnosis were included. Metritis was defined as fetid, watery, reddish-brownish discharge with or without fever, and cure was defined as the absence of metritis signs 12 d after diagnosis. Cows were randomly allocated to remain untreated (CON; n = 147) or receive subcutaneous injections of 6.6 mg/kg of ceftiofur crystalline-free acid at enrollment and 72 h later (CEF, n = 168). Additionally, a random subset of 150 nonmetritic cows (NMET) was also included to compare milk production, reproductive performance, and culling responses. Cow-related factors evaluated include plasma concentrations of nonesterified fatty acids, β-hydroxybutyrate, and haptoglobin (Hp), parity, rectal temperature, and days in milk (DIM) at metritis diagnosis, vulvovaginal laceration (VL), BCS, dystocia, twins, and retained placenta. Among CON cows, DIM at metritis diagnosis was positively associated with metritis cure [threshold = 8, area under the curve (AUC) = 0.67], whereas plasma Hp concentration tended to be negatively associated with cure of metritis (threshold = 0.54 mg/mL, AUC = 0.64). Among CEF cows, DIM at metritis diagnosis (threshold = 5, AUC = 0.67) and dystocia were positively associated with metritis cure, whereas VL and Hp (threshold = 0.78 mg/mL, AUC = 0.76) were negatively associated with cure. For CON cows that were diagnosed with metritis after 8 DIM or had plasma Hp concentration ≤0.54 mg/mL, milk production, pregnancy, and culling risk were comparable to NMET cows. However, performance was impaired when cows that developed metritis at ≤8 DIM or had Hp >0.54 mg/mL were left untreated. Among CEF cows, Hp, DIM at metritis diagnosis, dystocia, and VL were associated with metritis cure. Milk yield, reproductive performance, and culling losses are more pronounced among CEF cows when metritis was diagnosed at ≤5 DIM, Hp >0.78 mg/mL, or if they had VL or dystocia. In conclusion, these data indicate that timing of the onset of metritis and inflammatory biomarkers could be used for the development of a selective therapy strategy for metritis, but more research is needed to identify more accurate predictors of metritis spontaneous cure and treatment failure.

[Bispecific Antibodies: Formats and Areas of Application]

Bispecific antibodies capable of simultaneously binding two targets have been studied for many years with a view to their implementation in clinical practice. Unique biological and pharmacological properties, as well as the diversity of their formats, make it possible to consider bispecific antibodies as promising agents for use in various procedures: from visualization of intracellular processes to targeted anticancer therapy. Bispecific antibodies help to determine more precisely the therapeutic target, thereby increasing the efficiency of therapy and reducing the probability of side effects. The present review describes the main formats of bispecific antibodies, methods for their generation, and possibilities for practical application.