Biocontrol of multidrug resistant pathogens isolated from fish farms using silver nanoparticles combined with hydrogen peroxide insight to its modulatory effect

This study was divided into two parts. The first part involved the isolation, and detection of the prevalence and antimicrobial resistance profile of Aeromonas hydrophila, Pseudomonas aeruginosa, and Vibrio species from Nile tilapia fish and marine aquatic water. One hundred freshly dead Nile tilapia fish were collected from freshwater aquaculture fish farms located in Al-Abbassah district, Sharkia Governorate, and 100 samples of marine aquatic water were collected from fish farms in Port Said. The second part of the study focused on determining the in vitro inhibitory effect of dual-combination of AgNPs-H2O2 on bacterial growth and its down regulatory effect on crucial virulence factors using RT-PCR. The highest levels of A. hydrophila and P. aeruginosa were detected in 43%, and 34% of Nile tilapia fish samples, respectively. Meanwhile, the highest level of Vibrio species was found in 37% of marine water samples. Additionally, most of the isolated A. hydrophila, P. aeruginosa and Vibrio species exhibited a multi-drug resistance profile. The MIC and MBC results indicated a bactericidal effect of AgNPs-H2O2. Furthermore, a transcriptional modulation effect of AgNPs-H2O2 on the virulence-associated genes resulted in a significant down-regulation of aerA, exoU, and trh genes in A. hydrophila, P. aeruginosa, and Vibrio spp., respectively. The findings of this study suggest the effectiveness of AgNPs-H2O2 against drug resistant pathogens related to aquaculture.

The effect of butyric acid and nucleotides supplementation on broiler (Gallus gallus domesticus) growth performance, immune status, intestinal histology, and serum parameters

Background

Butyric acid and its derivatives support the immune system, lessen inflammation, and lessen oxidative stress in broilers in addition to preserving gut homeostasis and epithelial integrity. Broiler performance has also been demonstrated to rise with the addition of nucleotides to the diet.

Aim

The purpose of the study was to ascertain the effects of butyric acid and nucleotides added to feed on the overall performance, immunity, oxidant/antioxidant enzyme levels, intestinal histology, and hepatic functions of broilers.

Methods

Four experimental groups of thirty chickens, each were used in the present study. The groups were assigned as a control group that received normal diet without additives, butyrate (B) group received the diet supplemented with butyric acid (250 g/ton feed), nucleotides (N) group received the diet supplemented with nucleotides (200 g/ton feed), and the fourth group received the diet supplemented with a combination of butyrate and nucleotide (BN) (250 g/ton B feed, and 200 g/ton N feed, respectively). Necrotic enteritis was produced in ten birds from each group to assess the immune-modulatory effect of these supplements, antioxidant status, intestinal histology, and liver functions were measured in all experimental groups.

Results

The addition of butyric acid and nucleotides to feed enhanced body weight, growth performance, hepatic functions, and antioxidant capabilities. Histological sections of the gut from challenged or unchallenged (with necrotic enteritis) groups in the BN group showed considerable improvement, as shown by strong proliferation in intestinal crypts and villus enterocytes.

Conclusion

Nucleotides and butyric acid can be added to broiler feeding regimens to enhance growth and health.

Novel In Vivo Assessment of Antimicrobial Efficacy of Ciprofloxacin Loaded Mesoporous Silica Nanoparticles against Salmonella typhimurium Infection

Salmonella enterica serovar Typhimurium (S. typhimurium) is known for its intracellular survival, evading the robust inflammation and adaptive immune response of the host. The emergence of decreased ciprofloxacin (CIP) susceptibility (DCS) requires a prolonged antibiotic course with increased dosage, leading to threatening, adverse effects. Moreover, antibiotic-resistant bacteria can persist in biofilms, causing serious diseases. Hence, we validated the in vitro and in vivo efficacy of ciprofloxacin-loaded mesoporous silica nanoparticles (CIP–MSN) using a rat model of salmonella infection to compare the oral efficacy of 5 mg/kg body weight CIP–MSN and a traditional treatment regimen with 10 mg/kg CIP postinfection. Our results revealed that mesoporous silica particles can regulate the release rate of CIP with an MIC of 0.03125 mg/L against DCS S. typhimurium with a greater than 50% reduction of biofilm formation without significantly affecting the viable cells residing within the biofilm, and a sub-inhibitory concentration of CIP–MSN significantly reduced invA and FimA gene expressions. Furthermore, oral supplementation of CIP–MSN had an insignificant effect on all blood parameter values as well as on liver and kidney function parameters. MPO and NO activities that are key mediators of oxidative stress were abolished by CIP–MSN supplementation. Additionally, CIP–MSN supplementation has a promising role in attenuating the elevated secretion of pro-inflammatory cytokines and chemokines in serum from S. typhimurium-infected rats with a reduction in pro-apoptotic gene expression, resulting in reduced S. typhimurium-induced hepatic apoptosis. This counteracted the negative effects of the S. typhimurium challenge, as seen in a corrected histopathological picture of both the intestine and liver, along with increased bacterial clearance. We concluded that, compared with a normal ciprofloxacin treatment regime, MSN particles loaded with a half-dose of ciprofloxacin exhibited controlled release of the antibiotic, which can prolong the antibacterial effect.

Responses to COVID-19: The role of performance in the relationship between small hospitality enterprises' resilience and sustainable tourism development

Tourism is one of the hardest-hit industries by the global pandemic of Novel Coronavirus (COVID-19). Small tourism enterprises have been heavily affected and have had difficulty in business recovery. This research is an early attempt to explore the direct impact of small hospitality enterprises' resilience on sustainable tourism development as well as indirect impact through performance. A pre-tested questionnaire survey was self-administered to owner-managers of small hospitality enterprises in Greater Cairo, Egypt. The results of structural equation modeling (SEM) using AMOS showed a positive, direct, and significant impact of resilience (planned and adaptive) on sustainable tourism development and indirect influence through performance. The results of the multi-group analysis showed that enterprise type has a significant effect on the results, where restaurant owner-managers expressed more resilience than their hotel counterparts. Several theoretical (for scholars) and practical implications for tourism policy-makers and owner-managers have been discussed and elaborated.

Chemotherapeutic Potential of Epimedium brevicornum Extract: The cGMP-Specific PDE5 Inhibitor as Anti-Infertility Agent Following Long-Term Administration of Tramadol in Male Rats

Epimedium brevicornum Maxim (EbM) is a well-known Chinese herb that has been widely used for the treatment of several diseases. The main purpose of this study is to examine the role of Epimedium brevicornum extract in certain andrological parameters in rats as a natural modulator for adverse viewpoints associated with chronic administration of tramadol (TAM). Fifty rats were categorized into five groups. Untreated rats were known as Group I, whereas rats in Groups II and III were administered 2.43 g/kg/day of E. brevicornum extract and 50 mg/kg/day of TAM for 130 consecutive days, respectively. Both of Groups IV and V were administered TAM for 65 successive days, followed by concomitant use of both drugs for another 65 days, with the E. brevicornum extract at doses of 0.81 and 2.43 g/kg/day, respectively. TAM showed an injurious effect on sperm attributes, serum hormones, tissue malondialdehyde, superoxide dismutase, and nitric oxide. Elevation of the apoptotic marker Bax and a reduction of Bcl2 were recorded. Histopathological abnormalities have been reported in rat testicles. Rats treated with E. brevicornum extract with TAM showed an improvement in all the parameters tested. It could be presumed that E. brevicornum extract plus TAM exhibits a promising effect on the enhancement of male anti-infertility effects.

Chemotherapeutic Potential of Carthamus Oxycantha Root Extract as Antidiarrheal and In Vitro Antibacterial Activities

Our research work was designed to investigate the curative and preventive effects of Carthamus oxycantha root extract against diarrhea and microorganisms. For the antibacterial experiment, the agar well diffusion method was used against standard bacteria Staphylococcus aureus, Escherichia coli, Pseudomonas aeroginosa, and Salmonella typhi, while for the assessment of antidiarrheal activity, castor oil and the magnesium sulfate-induced diarrhea method was used on albino, laboratory-bred (BALB/c) mice at a dose rate of 200 and 400 mg/kg (body weight, b.w) orally. The methanol extract of C. oxycantha significantly (p < 0.001) decreased the frequency of defecation, and wet stools in a dose depended on the manner of after receiving magnesium sulfate (2 g/kg (b.w)) and castor oil (1.0 mL/mice). Furthermore, the extract of C. oxycantha showed concentration-dependent antimicrobial properties against S. aureus followed by S. typhi, E. coli, and P. aeroginosa bacterial strains, with inhibitions ranging from 10.5–15 mm. These findings show significant results that C. oxycantha is effective as an antidiarrheal and antibacterial agent. However, further works are needed to establish its mode of action.