Evaluation of the Antimicrobial, Cytotoxic, and Physical Properties of Selected Nano-Complexes in Bovine Udder Inflammatory Pathogen Control

Purpose

Mastitis in dairy cows is a worldwide problem faced by dairy producers. Treatment mainly involves antibiotic therapy, however, due to widespread antibiotic resistance among bacteria, such treatments are no longer effective. For this reason, scientists are searching for new solutions to combat mastitis, which is caused by bacteria, fungi, and algae. One of the most promising solutions, nanotechnology, is attracting research due to its biocidal properties. The purpose of this research was to determine the biocidal properties of nanocomposites as a potential alternative to antibiotics in the control of mastitis, as well as to determine whether the use of nanoparticles and what concentration is safe for the breeder and the animal.

Patients and Methods

In this study, the effects of Ag, Au, Cu, Fe, and Pt nanoparticles and their complexes were evaluated in relation to the survival of bacteria and fungi isolated from cattle diagnosed with mastitis, their physicochemical properties, and their toxicity to bovine and human mammary epithelial cells BME-UV1 and HMEC (human microvascular endothelial cells). Moreover, E. coli, S. aureus, C. albicans, and Prototheca sp. invasion was assessed using the alginate bead (bioprinted) model. The NPs were tested at concentrations of 25, 12.5, 6.25, 3.125, 1.56 mg/l for Au, Ag, Cu and Fe NPs, and 10, 5, 2.5, 1.25, 0.625 mg/l for Pt.

Results

With the exception of Fe and Pt, all exhibited biocidal properties against isolates, while the AgCu complex had the best effect. In addition, nanoparticles showed synergistic effects, while the low concentrations had no toxic effect on BME-UV1 and HMEC cells.

Conclusion

Synergistic effects of nanoparticles and no toxicity to bovine and human cells might, in the future, be an effective alternative in the fight against microorganisms responsible for mastitis, and the implementation of research results in practice would reduce the percentage of dairy cows suffering from mastitis. The problem of increasing antibiotic resistance is posing a global threat to human's and animal's health, and requires comprehensive research to evaluate the potential use of nanoparticles - especially their complexes - as well as to determine whether nanoparticles are safe for the breeders and the animals. The conducted series of studies allows further consideration of the use of the obtained results in practice, creating a potentially new alternative to antibiotics in the treatment and prevention of mastitis in dairy cattle.

In Vitro Evaluation of the Antimicrobial Properties of Nanoparticles as New Agents Used in Teat Sealants for Mastitis Prevention in Dry Cows

Mastitis prevention and treatment in dry cows are complex issues with limited solutions. The most common is intramammary antibiotic treatment. However, the effectiveness of this treatment varies among countries and even within herds in the same region. Therefore, it is necessary to develop new strategies for dry cow therapy. Metal nanoparticles (NPs), which have strong biocidal properties for treating diseases caused by bacteria, fungi, and algae, are increasingly used to reduce antibiotic use. In this study, AuNPs, CuNPs, AgNPs, PtNPs, NP-FeCs, and their triple complexes were used at different concentrations to evaluate their practical use in treating cows during their dry period. The nanoparticles were in hydrocolloid form and were added separately to form a mixture with beeswax, a mixture with oil, or a mixture based on vegetable glycerin and propylene glycol. The NPs' concentrations were 0.5, 1, 2, and 5 ppm. Gram-positive and Gram-negative bacteria, and fungi isolated from cows diagnosed with mastitis were used to determine pathogen viability. The results indicated that AuNPs, CuNPs, AgNPs, and their complexes show biocidal properties against mastitis pathogens. AgNPs at 5 ppm had the strongest biocidal properties and reduced Streptococcus agalactiae's survival rate by 50%; however, the nanoparticle complexes showed poor synergism. The strongest biocidal properties of NPs in wax and in glycerin mixed with glycol were shown against Escherichia coli. Additionally, low nanoparticle concentrations showed no cytotoxicity for BME-UV1 bovine cells, suggesting that these mixtures might be used for further in vivo testing.

In Vitro Studies of Nanoparticles as a Potentially New Antimicrobial Agent for the Prevention and Treatment of Lameness and Digital Dermatitis in Cattle

Digital dermatitis (DD) is the second most prevalent disease in dairy cattle. It causes significant losses for dairy breeders and negatively impacts cows' welfare and milk yield. Despite this, its etiology has not been entirely identified, and available data are limited. Antibiotic therapy is a practical method for managing animal health, but overuse has caused the evolution of antibiotic-resistant bacteria, leading to a loss in antimicrobial efficacy. The antimicrobial properties of metal nanoparticles (NPs) may be a potential alternative to antibiotics. The aim of this study was to determine the biocidal properties of AgNPs, CuNPs, AuNPs, PtNPs, FeNPs, and their nanocomposites against pathogens isolated from cows suffering from hoof diseases, especially DD. The isolated pathogens included Sphingomonas paucimobilis, Ochrobactrum intermedium I, Ochrobactrum intermedium II, Ochrobactrum gallinifaecis, and Actinomyces odontolyticus. Cultures were prepared in aerobic and anaerobic environments. The viability of the pathogens was then determined after applying nanoparticles at various concentrations. The in vitro experiment showed that AgNPs and CuNPs, and their complexes, had the highest biocidal effect on pathogens. The NPs' biocidal properties and their synergistic effects were confirmed, which may forecast their use in the future treatment and the prevention of lameness in cows, especially DD.

Hepatitis A virus (HAV) RNA detection in Polish blood donors and likely transmissions through blood components during the 2017-2019 epidemic

BACKGROUND

In Poland, hepatitis A virus (HAV) RNA screening was performed in plasma for fractionation usually immediately before shipment.

OBJECTIVE

Our goal was to study epidemiology, rate of transfusion transmitted HAV during epidemic (2017-2019), and viral characteristics of infected plasma donors.

STUDY DESIGN AND METHODS

HAV RNA was tested in 1,866,590 donations from 1,210,423 donors using RT-PCR in mini pools of 96 (MP96) or TMA in MP16. Virological characteristics included RNA level (RL), antibody testing, and sequencing.

RESULTS

Twenty-one HAV infections were identified (1.13/100,000 donations; 95% confidence interval [95% CI]: 0.74-1.72) and (1.73/100,000 donors; 95% CI: 1.35-2.65). The Blood Transfusion Centers were also informed about three donors, who were hospitalized for hepatitis A soon after their blood donation. In addition, we identified a donor, who had reactive result for HAV after receiving HAV vaccination. He tested positive twice 10 days after receiving the first and the second dose. The highest RL was 16 million IU/ml, mean 1,706,905 IU/ml, and median 220 IU/ml. The longest detectable RL lasted for 113 days. HAV-infected donors were seronegative (36%) or IgM positive (64%). We followed up on 12 HAV contaminated blood components issued for transfusion. In two out of seven identified patients viral transmission was confirmed (28.6%).

CONCLUSION

Based on our results, we propose a 6 month deferral after HAV infection and 14 days post HAV vaccination. The infectivity rate was below 30%. The HAV RNA testing could be considered as an additional safeguard against HAV transmission at the time of increased incidence of HAV infections in the general population.

Silver and Copper Nanoparticles as the New Biocidal Agents Used in Pre- and Post-Milking Disinfectants with the Addition of Cosmetic Substrates in Dairy Cows

Mastitis is one of the most common issues for milk producers around the world. Antibiotic therapy is often ineffective, and therefore, scientists must find a new solution. The aim of this paper is to estimate the influence of common and well-known cosmetic substrates and mixtures of nanoparticles (NPs) and cosmetic substrates on the viability of frequently occurring mastitis pathogens, Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The obtained results suggest that only collagen + elastin and glycerine influenced and increased bacteria viability. In case of the rest of the cosmetic substrates, the viability of E. coli and S. aureus was decreased, and the results were statistically significant (p ≤ 0.01). Prepared pre-dipping and dipping mixtures decrease (p ≤ 0.01) the viability of the mentioned pathogens. The obtained results of the in vitro analysis are very promising. In the next step, prepared mixtures should be tested in different herd conditions if they can be used in mastitis prevention or decrease the number of subclinical mastitis cases. Furthermore, these mixtures could become an interesting alternative for organic milk production where conventional preparations and antibiotics are forbidden. However, further analysis, especially on the influence of prepared mixtures on other bacteria species and, algae, fungi, are necessary.

The relationship between plasma β-hydroxybutyric acid and conjugated linoleic acid in milk as a biomarker for early diagnosis of ketosis in postpartum Polish Holstein-Friesian cows

Background

The aim of this study was to investigate the association between plasma β-hydroxybutyric acid (BHBA) and conjugated linoleic acid in postpartum Polish Holstein-Friesian (PHF) cows. The experiment was carried out at an experimental dairy farm, where a herd of approximately 350 cows was kept. Samples were taken at six time points: between days 5–7, 8–14, 15–21, 22–28, 29–35, and 36–42, resulting in 510 samples of both milk and blood. The cows involved in the experiment were divided into two groups – ketotic and healthy – by taking into account general health symptoms, blood serum BHBA, and non-esterified fatty acids (NEFA) concentration at 5–7 days postpartum.

Results

In the first week of lactation, at 5–7 day in milk (DIM), the study showed a 53% lower level of C18:2 cis-9 trans-11 (CLA9) and an 80% lower level of C18:2 trans-10 cis-12 (CLA10) in cows with diagnosed ketosis compared to healthy cows. In the second week of lactation (8–14 DIM), a 34% lower level of CLA9 and a 54% lower level of CLA10 was found in the group of cows with BHBA levels > 1.2 mmol/L. Additionally, Pearson correlation analysis showed significant negative correlation between BHBA x CLA9 and BHBA x CLA10 in the first week of lactation: − 0.732and − 0.821, respectively.

Conclusion

The study shows that that both CLA9 and CLA10 can be used as markers for the early diagnosis of elevated blood levels of BHBA in postpartum Polish Holstein-Friesian cows.

[Risk of transmission of blood-derived pathogens by transfusion in Poland]

Blood transfusion in Poland is the safest in history. High virological level of safety has been achieved mainly by improving not only the qualification of donors and methods used for donor screening, but also applying leukoreduction, pathogen reduction technology and grace period for serum.In this article, we discuss the improvement of the epidemic situation among blood donors for hepatitis B virus (HBV) and hepatitis C virus (HCV) and the increasing trend for HIV. Preliminary results of residual risk calculation for these pathogens are presented.Hepatitis E virus (HEV) and Babesia microti were considered as new factors potentially relevant for the safety of blood transfusion in our country. Due to evidence of West Nile virus (WNV) circulation in the ecosystem in Poland, it is also necessary to monitor the infections with this pathogen.In this article, it was emphasized that the reporting of all possible complications associated with transfusion and meticulous implementation of the look-back procedure play a key role for monitoring the risk of transmission of infectious agents by blood. It is especially important in view of the increasing epidemiological problems associated with emerging infectious agents.

[Parvovirus B19 DNA testing in Polish blood donors, 2004-2010]

Since 2004 Polish blood donors have been tested for parvovirus B19 (B19V) DNA. The screening testing has been performed in donors of plasma for fractionation and anti-D and anti-HBs production and donors of erythrocytes used for immunization. AIM is to present methods of the testing, quality control and results in period 2004-2010.

MATERIAL AND METHODS

Testing was performed in individual donation testing (IDT) in Regional Blood Transfusion Center (RBTC) in Lublin or in pools of 24 in Institute of Haematology and Transfusion Medicine in Warsaw (IHTM). Quantitative testing with real-time PCR was preceded with nucleic acid isolation on silica based methods (Prepito Viral DNA/RNA, Chemagen and QIAamp DNA Mini Kit, QIAGEN). Amplification was performed initially with home made method and later with commercial assay (Artus Parvo B19 RG PCR Kit on Rotor Gene 6 000). In total 17 625 donations were tested: 8 539 in pools and 9 090 individually. Beside routine external quality control programmes in which both laboratories participated (Proficiency Study VQC,Amsterdam, Holand; EQA Programe, Glasgow, Scotland), panel containing negative samples, positive with very high DNA B 19V level and plasma infected with genotype 2 was prepared for RBTC in Lublin.

RESULTS

B19V infection frequency was 1:980 donations, low viraemic donations were detected most frequently (1:1 037). It was identified only one donation with DNA load that could cause potential health risk for plasma product recipients (1:17 625). In one of the donors B 19V DNA was observed for 3 years and 3 months. In acute or persistent phase of infection no clinical or laboratory symptoms (morphology of peripheral blood, ALT) were observed. Due to risk of underestimation of viral load connected with viral genome polymorphism all donations with B19V positive result were not allowed to be clinically used.

False negative results in high viremia parvovirus B19-samples tested with real-time PCR

Extremely high viremia is observed during some viruses infection, especialy in immunocompromised patients. False negative results of Parvovirus B 19 DNA tests performed with real-time PCR in high viremic samples are reported. The way of fluorescence diagrams analysis and algorithm of positive result confirmation to exclude such phenomenon are proposed.

[Non-invasive fetal RhD typing and RhD negative pregnant women--preliminary observations]

OBJECTIVES

For a follow up of a pregnancy in a RhD neg women it is crucial to learn whether her fetus is RhD pos or neg.

AIM

Detection of fetal RHD gene in the plasma of RhD neg mother in various periods of pregnancy and a comparison with RhD of a newborn. 45 plasma samples from various periods of pregnancy from 28 RhD neg women.

MATERIAL AND METHODS

Examination of: RHD (exon 7 and 10), SRY, GSTM1 and ACE using real-time PCR.

RESULTS

Fetal RHD was detected in all 23 mothers with RhD pos child; in one of them, in the 12th week of gestation, RHD was detected only using primers for exon 7, however in the 21st--the presence of both RHD exons was confirmed. Five mothers delivered RhD neg newborns--both RHD exons were not detected. In all 5 cases other fetal genes were examined to be certain that the fetal DNA was analysed. In all 3 mothers who delivered RhD neg boys, the SRY was detected. Among 2 mothers who delivered RhD neg girls, the presence of fetal DNA was confirmed in one, by GSTM1 detection.

CONCLUSIONS

1) Real-time PCR is an appropriate, non-invasive method for fetal RhD examination. 2) Two RHD exons should be examined. 3) Control genes should be investigated and found to be sure that negative result of the RHD was not false negative due to the lack of fetal DNA; SRY is an appropriate control for boys, while for girls further investigations are needed, which are in progress.

DRB1 alleles in relation to severity of liver disease in patients with chronic hepatitis C

The aim of our study was analysis of relation between HLA class II antigens and the liver disease severity in chronic hepatitis C (CHC) patients. The subject of analysis was data obtained from 134 CHC patients with disease confirmed by histopathologic test (F/M: 62/72; age 16-74; average age 41.4 +/- 12.7 yrs), HCV RNA-positive, HbsAg- and HIV-negative with no coexistence of any other liver diseases. Liver biopsy specimens were estimated according to Ishak's criterions (grading 0-18; staging 0-6). HLA DRB1 alleles were determined by a commercial method INNOLiPA DRB (Innogenetics, Belgium). Statistical analysis considered alleles occurring with frequency higher than 10%. The necroinflammatory activity (average grading score) was compared in groups of patients with- and without particular allele. The frequency of each allele's occurrence was analyzed according to patients sex, age and staging score of liver fibrosis. In statistical analysis t-Student test and chi-squared test with or without Yates' correction were applied. Statistically significant correlation was found between occurrence of DRB1*13 and DRB1*07 alleles and necroinflammatory activity intensification, and between occurrence of DRB1*13 allele and progression of liver disease. Mild liver damage, instead, expresses statistically significant relation with DRB1*11 allele.

Follow-up studies of a representative sample of children with severe mental handicap in Poland

A representative sample of 260 Polish children, aged 5-14 years, identified between 1964 and 1965 in an epidemiological study as severely mentally handicapped (IQs ranging from 0 to 51) were followed up twice: (I) after 10 years (in 1975-1976); and (II) after 23 years (in 1987-1988). At both follow-ups, all surviving subjects were contacted, and psychological and sociological data were gathered; the findings presented here pertain mostly to follow-up II. The great majority of subjects (85%) lived with their families, and the remainder resided in an institution. Only 10% of subjects (living with one exception in families) currently had a higher level of intellectual functioning than that of severe mental handicap. Among this group were individuals of relatively better health, without speech disorders, who had attended schools, had some vocational training, had been or were employed, and had families of their own, i.e. were self-dependent with a life-style similar to that of other people of their age and social background. Of the remainder, about 40% retained the same relative level of intellectual and social functioning, and about 50% deteriorated, particularly those in institutions. This latter group has remained in the role of permanent children, depending on others for care and maintenance.