Development of novel Streptococcus equi vaccines with an assessment of their immunizing potentials and protective efficacies.

Strangles is a highly contagious disease of the equine upper respiratory tract caused by Streptococcus equi subspecies. Streptococcus equi subsp. equi (S. equi) and Streptococcus equi subsp. zooepidemicus (S. zooepidemicus) was isolated, as local, hot, and field strains, from horses clinically suffering from respiratory distress. The isolated Streptococci were identified using bacteriological and molecular techniques. Four formulations of inactivated S. equi vaccines were developed and evaluated. The first formulation was prepared using the S. equi isolates, adjuvanted with MONTANIDE GEL adjuvant, while the second formulation was adjuvanted with MONTANIDE ISA-70 adjuvant. The other 2 formulations were inactivated combined vaccines prepared from both S. equi and S. zooepidemicus isolates. The 3rd formulation was the combined isolates adjuvanted with MONTANIDE GEL while the 4th formulation was the combined isolates adjuvanted with MONTANIDE ISA-70. The developed vaccines' physical properties, purity, sterility, safety, and potency were ensured. The immunizing efficacy was determined in isogenic BALB/c mice and white New Zealand rabbits using the passive hemagglutination test. Also, the antibodies' titer of the combined S. equi and S. zooepidemicus vaccine adjuvanted with MONTANIDE ISA-70 in foals was tracked using an indirect enzyme-linked immunosorbent assay. The protective efficacy of the developed vaccines was determined using a challenge test in both laboratory and field animal models, where a 75% protection rate was achieved. The combined vaccine proved to be more efficacious than the monovalent vaccine. Also, the MONTANIDE ISA-70 adjuvant provided significant protective efficacy than the MONTANIDE GEL. The current work is introducing a very promising mitigative and strategic controlling solution for strangles.

Development of a lateral flow device for rapid simultaneous multiple detections of some common bacterial causes of bovine mastitis.

Objective: This work was conducted for the development of a 5-combi lateral flow immunochromatographic kit (LFK) for rapid and simultaneous identification of the common bacterial causes of bovine mastitis. The following pathogens are the identification targets of this kit: Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, Streptococcus agalactiae, and Streptococcus pyogenes in milk samples from suspected bovine mastitis cases. The conventional microbiological identification of these agents is not only time-consuming and requires a fully equipped laboratory but also requires experienced personnel. Materials and Methods: Rabbit polyclonal antibodies (PAbs) specific to the antigenic components of the selected pathogens were prepared, and the pathogen-specific IgG was separated, purified, and conjugated with nanogold that was laid on the conjugate pad. Guinea pig PAbs specific to the microbial antigens of the selected pathogens were prepared, and their IgG content was separated, purified, and used as a capture antibody in the test (T) line on the nitrocellulose (NC) strips. Goat anti-rabbit IgG antibodies were used to capture the rabbit antibodies in the control (C) line of NC strips. The kit was held in a device comprising five strip-holding channels for the above-mentioned five bacterial species antigens. The developed LFK was evaluated, and its sensitivity and specificity were determined. Results: The developed kits were applied for the examination of bovine milk samples from suspected mastitis cases, and the average sensitivity, specificity, and accuracy of 5-combi LFK for the detection of the five selected bacterial species compared to bacteriological examination (gold standard test) were 93.90%, 80.83%, and 90.53%, respectively. The minimal microbial count that gave positive results using the developed LFK was 103 colony forming unit/ml. Treatment of the milk samples with an application buffer and its pre-incubation in trypticase soy broth for 6 h at 37°C before testing significantly increased the sensitivity of the prepared LFK. The developed kit proved simple and convenient, and the results could be obtained in less than 10 min.

Development of Lateral Flow Immunochromatographic Test for Rapid Detection of SARS-CoV-2 Virus Antigens in Clinical Specimens.

In the presented study, we developed a nanogold lateral glow immunoassay-based technique (LFI-COVID-19 antigen test) for the detection of SARS-CoV-2 nucleocapsid proteins; the developed LFI-COVID-19 Ag test has been tested for limit of detection (LOD), cross-reactivity and interfering substances, and performance. It was found that the performance of the developed LFI-COVID-19 antigen test when it was evaluated by RT-qPCR indicated 95, 98, and 97% for sensitivity, specificity and accuracy, respectively. This complies with the WHO guidelines. It was concluded that the developed LFI-COVID-19 antigen test is a point of care and an alternative approach to current laboratory methods, especially RT-qPCR. It provides an easy, rapid (within 20 min), and on-site diagnostic tool for COVID-19 infection, and it is a cheap test if it is manufactured on a large scale for commercial use.

Early and Mid-Term Results After Repair of Ischaemic Mitral Regurgitation with Complete Annuloplasty Ring and Incomplete Ring.

BACKGROUND: The choice of ring type for mitral valve (MV) repair is still debatable and usually is left to the surgeon's discretion. AIM: The aim of this study was to compare the early and mid-term results after repair of ischaemic mitral regurgitation (MR) with complete and incomplete annuloplasty rings. METHODS: Collected data included preoperative assessment (age, sex, comorbidities, clinical status, NYHA grade, and the EURO score); intraoperative details (echocardiography, degree of MR, and cross-clamp time); and results (the length of ICU and hospital stay, duration and need for inotropes, duration of mechanical ventilation, and postoperative adverse events). Follow up after discharge included assessment of dyspnea status, the degree and progression of MR, and left ventricular function and dimensions. RESULTS: The present study included 133 patients: 61 with incomplete rings and 72 with complete rings inserted. There was no significant difference in the rate of postoperative complications between the two groups, apart from a significantly higher percentage of patients with incomplete ring who required prolonged ventilation >24 hours (P = 0.002). There were no significant differences between the two groups, regarding the grade of residual MR (P = 0.464), postoperative dyspnea status (P = 0.723), 30-day mortality rate (P = 0.687), and mean duration of survival (P = 0.276). CONCLUSION: The choice of incomplete or complete annuloplasty ring was not associated with a marked difference in the early and midterm results of ischaemic MV repair.

Early and Midterm Results of Stent Endarterectomy for Left Anterior Descending Coronary Artery "Full Metal Jacket".

OBJECTIVE: Modern coronary interventional practice can result in coronary vessels that are totally stented. The term "full metal jacket" has been coined to refer to vessels that have an overlapping stent in series along the whole length of the vessel. This poses a serious challenge to surgical revascularization, particularly when a left internal thoracic artery (LITA) to the left anterior descending (LAD) needs to be undertaken. We evaluated the early and midterm results of on-pump coronary artery bypass grafting (CABG) following "stent endarterectomy" for the LAD with LITA to LAD grafting. METHODS: During October 2017 to September 2020, 21 patients presented with multi-vessel disease and a totally occluded LAD with a stent full metal jacket. No distal target for LITA grafting was available, despite a viable myocardial territory. The LAD was endarterectomised, removing the column of totally occluded stents with the medial wall of the vessel, leaving the proximal stent in place to avoid competitive flow. Long length anastomosis was then undertaken with the LITA graft. Postoperatively, patients were followed up clinically and by coronary computed tomography (CT) angiography at 6- and 18-month intervals. All patients were discharged on a combination of aspirin and warfarin for three months and then aspirin and clopidogrel for the rest of the first year and then aspirin alone for life. RESULTS: Patients had a mean age of 58.07 ± 2.06 yr. Sixteen (76.2%) were males, 13 (61.9%) patients were diabetics, 18 (85.7%) were hypertensive, 15 (71.4%) were dyslipidemic, six (28.6%) were obese, 11 (52.4%) were smokers, and five (23.8%) had positive family history of ischemic heart disease (IHD). The number of grafts per patient ranged 3-5, with a mean cross-clamp time of 64.71± 8.84 min. There were no postoperative deaths nor MI clinically, by electrocardiogram (ECG) criteria nor by troponin or CK-MB. In-hospital complications included one (4.8%) patient who required re-exploration for bleeding, one (4.8%) developed a superficial wound, and three (14.3%) developed atrial fibrillation (AF), during their hospital stay. Mean hospital stay was 7.71±1.73 days. All patients completed the 6-month follow up showing patent LITA to LAD with coronary CT angiography. One patient was lost to follow up after six months; five patients are awaiting their 18-month CT angiography, while 15 (71.4%) patients have completed their 18-month CT angiography, and all have a patent LITA to LAD. CONCLUSIONS: Stent endarterectomy for a totally occluded LAD with a full metal jacket and viable myocardial territory is a safe procedure with good early and midterm results. This technique should be considered in these difficult cases presenting for revascularisation when no other option is available.

Preparation and evaluation of Salmonella Enteritidis antigen conjugated with nanogold for screening of poultry flocks.

AIM: The present work aimed to develop lateral flow immunochromatographic strip (ICS) test for detection of Salmonella Enteritidis (SE) specific antibodies in chicken sera. MATERIALS AND METHODS: A rapid lateral flow immunochromatographic test (LFIT) has been developed, in which SE Group D antigen labeled with the gold chloride molecules laid on the conjugate pad. Staphylococcus aureus protein A was used as capture antibody at the test line (T) of a nitrocellulose (NC) membrane and anti-SE antigen-specific rabbit antibodies were used as capture antibody at the control line (C) of the NC strip in the lateral flow layout device. RESULTS: Using the developed LFIT, the minimal amount of SE-specific antibodies that can be detected in chicken serum sample was 1427 enzyme-linked immunosorbent assay (ELISA) unit/100 µl that was equal to 0.1 µg (Ab)/100 µl sample. 100 suspected serum samples collected from a poultry flock were tested with the prepared SE-LFIT kits and the locally prepared stained Salmonella antigen, and the results were compared with those obtained from examination of these samples with Salmonella Group D antibody ELISA kit as the gold standard test. The sensitivity, specificity, and accuracy of the prepared SE-LFIT antigen kits were 94.4%, 90%, and 94%, respectively, while those obtained with stained Salmonella antigen were 88.8%, 90%, and 89%, respectively. CONCLUSION: The developed test is a simple field rapid test of high sensitivity, specificity, and accuracy that can improve and facilitates rapid field surveillance of salmonellosis among chickens.

Leptospirosis in animals and human contacts in Egypt: broad range surveillance.

INTRODUCTION: Leptospirosis is a re-emerging zoonotic disease of humans and animals worldwide. The disease is caused by pathogenic species of the genus Leptospira. These organisms are maintained in nature via chronic renal infection of carrier animals, which excrete the organisms in their urine. Humans become infected through direct or indirect exposure to infected animals and their urine or through contact with contaminated water and soil. This study was conducted to investigate Leptospira infections as a re-emerging zoonosis that has been neglected in Egypt. METHODS: Samples from 1,250 animals (270 rats, 168 dogs, 625 cows, 26 buffaloes, 99 sheep, 14 horses, 26 donkeys and 22 camels), 175 human contacts and 45 water sources were collected from different governorates in Egypt. The samples were collected from different body sites and prepared for culture, PCR and the microscopic agglutination test (MAT). RESULTS: The isolation rates of Leptospira serovars were 6.9%, 11.3% and 1.1% for rats, dogs and cows, respectively, whereas the PCR results revealed respective detection rates of 24%, 11.3% and 1.1% for rats, dogs and cows. Neither the other examined animal species nor humans yielded positive results via these two techniques. Only six Leptospira serovars (Icterohaemorrhagiae, Pomona, Canicola, Grippotyphosa, Celledoni and Pyrogenes) could be isolated from rats, dogs and cows. Moreover, the seroprevalence of leptospiral antibodies among the examined humans determined using MAT was 49.7%. CONCLUSIONS: The obtained results revealed that rats, dogs and cows were the most important animal reservoirs for leptospirosis in Egypt, and the high seroprevalence among human contacts highlights the public health implications of this neglected zoonosis.

Leptospirosis in animals and human contacts in Egypt: broad range surveillance

INTRODUCTION: Leptospirosis is a re-emerging zoonotic disease of humans and animals worldwide. The disease is caused by pathogenic species of the genus Leptospira. These organisms are maintained in nature via chronic renal infection of carrier animals, which excrete the organisms in their urine. Humans become infected through direct or indirect exposure to infected animals and their urine or through contact with contaminated water and soil. This study was conducted to investigate Leptospira infections as a re-emerging zoonosis that has been neglected in Egypt. METHODS: Samples from 1,250 animals (270 rats, 168 dogs, 625 cows, 26 buffaloes, 99 sheep, 14 horses, 26 donkeys and 22 camels), 175 human contacts and 45 water sources were collected from different governorates in Egypt. The samples were collected from different body sites and prepared for culture, PCR and the microscopic agglutination test (MAT). RESULTS: The isolation rates of Leptospira serovars were 6.9%, 11.3% and 1.1% for rats, dogs and cows, respectively, whereas the PCR results revealed respective detection rates of 24%, 11.3% and 1.1% for rats, dogs and cows. Neither the other examined animal species nor humans yielded positive results via these two techniques. Only six Leptospira serovars (Icterohaemorrhagiae, Pomona, Canicola, Grippotyphosa, Celledoni and Pyrogenes) could be isolated from rats, dogs and cows. Moreover, the seroprevalence of leptospiral antibodies among the examined humans determined using MAT was 49.7%. CONCLUSIONS: The obtained results revealed that rats, dogs and cows were the most important animal reservoirs for leptospirosis in Egypt, and the high seroprevalence among human contacts highlights the public health implications of this neglected zoonosis. .

Position of totally thoracoscopic surgical ablation in the treatment of atrial fibrillation: an alternative method of conduction testing.

Recent advances in surgical techniques and understanding of the pathophysiology of atrial fibrillation has led to the development of a less invasive thoracoscopic surgical treatment including video-assisted bilateral pulmonary vein isolation using bipolar radiofrequency ablation clamps. More recently, the same operation became possible via a totally thoracoscopic approach. In this paper we describe technical aspects of the thoracoscopic approach to surgical treatment of AF and discuss its features, benefits and limitations. Furthermore, we present a new alternative technique of conduction testing using endoscopic multi-electrode recording catheters. An alternative electrophysiological mapping strategy involves a multi-electrode recording catheter designed primarily for percutaneous endocardial electrophysiologic mapping procedure. According to our initial experience, the recordings obtained from the multi-electrode catheters positioned around the pulmonary veins are more accurate than the recordings obtained from the multifunctional ablation and pacing pen. The totally thoracoscopic surgical ablation approach is a feasible and efficient treatment strategy for atrial fibrillation. The conduction testing can be easily and rapidly performed using a multifunctional pen or multi-electrode recording catheter.

Minimally invasive direct coronary artery bypass improves late survival compared with drug-eluting stents in isolated proximal left anterior descending artery disease: a 10-year follow-up, single-center, propensity score analysis.

OBJECTIVES: Minimally invasive direct coronary artery bypass (MIDCAB) has been proposed to reduce surgical morbidity and improve long-term outcomes compared with stenting in the treatment of isolated proximal left anterior descending artery. However, the survival benefit from MIDCAB still needs to be demonstrated, in particular, because percutaneous coronary intervention with drug-eluting stents (DES-PCI) continues to be considered the initial treatment strategy. We conducted a 10-year follow-up, single-center, propensity score-matched MIDCAB versus DES-PCI comparison. METHODS: A total of 1033 patients (303 MIDCAB and 730 DES-PCI) with isolated proximal left anterior descending disease were included. Propensity score matching was used to compare 303 pairs of MIDCAB and DES-PCI patients. RESULTS: MIDCAB and DES-PCI presented with comparable 30-day mortality (2 of 303 [0.6%] vs 1 of 303 [0.3%]; P=1.0). At 10 years, DES-PCI was associated with a 2.19-fold increased risk of late death (95% confidence interval, 1.15-4.17), a 2.0-fold increased risk of repeat revascularization (95% confidence interval, 1.20-3.47), and a 2.14-fold increased risk of the composite of death and repeat revascularization (95% confidence interval, 1.41-3.24). CONCLUSIONS: These findings strongly support a survival benefit from MIDCAB at long-term follow-up compared with DES-PCI in the treatment of isolated left anterior descending disease.

Does grafting of the left anterior descending artery with the in situ right internal thoracic artery have an impact on late outcomes in the context of bilateral internal thoracic artery usage?

BACKGROUND: Despite their well-established advantages, bilateral internal thoracic arteries (BITA) are still largely underused. This is partly because of the technical complexities associated with the use of the right internal thoracic artery (RITA) to guarantee the universally accepted gold standard left internal thoracic artery (LITA) to left anterior descending artery (LAD) graft. The use of the in situ RITA for LAD grafting is a less technically demanding strategy. The impact of this strategy on early and late outcomes is investigated in the context of BITA usage. METHODS: Among 1667 patients undergoing first-time isolated coronary artery bypass grafting using BITA, in situ RITA for LAD grafting was used in 546 patients compared with in situ LITA to LAD in 1121 patients. Propensity score matching was carried out to investigate the impact of in situ RITA to LAD on early and late outcomes including mortality and need for repeat revascularization. RESULTS: A total of 546 propensity matched pairs were available for comparison. In the propensity matched cohort, the mean follow-up time was 7.8±3.8 years. RITA to LAD did not increase the risk for late death (hazard ratio [HR], 0.78; 95% confidence interval [CI], 0.48-1.26), the need for repeat revascularization (HR, 0.83; 95% CI, 0.70-2.42), and the composite of death or repeat revascularization (HR, 0.81; 95% CI, 0.64-1.14). CONCLUSIONS: Using in situ BITA with retrosternal in situ RITA for LAD grafting is a technically less demanding, safe, and effective strategy that can increase usage of BITA by avoiding a composite graft configuration or technically challenging retrocaval routing of in situ RITA through the transverse sinus.