Magnolol attenuates macrophage pyroptosis triggered by Streptococcus equi subsp. zooepidemicus.

Streptococcus equi subsp. zooepidemicus (SEZ) is a zoonotic bacterial pathogen that causes life-threatening infections and various diseases such as meningitis, endocarditis and pneumonia. With the use of antibiotics being severely restricted in the international community, an alternative to antibiotics is urgently needed against bacterial. In the present study, the herbal extract magnolol protected mice against SEZ infection, reflected by increased survival rate and reduced bacterial burden. A pro-inflammatory form of cell death occurred in SEZ-infected macrophage. Magnolol downregulated the expression of pyroptosis-related proteins and reduced the formation of cell membrane pores in infected macrophages to suppress the development of subsequent inflammation. We further demonstrated that magnolol directly suppressed SEZ-induced macrophage pyroptosis, which partially protected macrophages from SEZ infection. Our study revealed that magnolol suppressed inflammation and protected mice against SEZ infection, providing a possible treatment for SEZ infection.

Neutrophil accumulation raises defence against Streptococcus equi ssp. zooepidemicus in the absence of Gasdermin D.

Streptococcus equi ssp. zooepidemicus (SEZ) predominantly acts as a zoonotic pathogen, capable of infecting a diverse range of animal species including human. Gasdermin D (GSDMD) exhibited comprehensive functions in host against different pathogenic microorganism. This study aimed to investigate the role of GSDMD in host against SEZ. Mice were administrated with SEZ via intranasal intubation for 24 h (3 × 106CFU), GSDMD protein expression significantly increased in the lung tissue of mice infected with SEZ. For further research on the role of GSDMD during SEZ infection, GSDMD-/- mice and WT mice were treated with SEZ via intranasal intubation for 24 h (3 × 106CFU). GSDMD-/- mice showed less severe lung tissue due to fewer bacteria colonization. Numerous neutrophils were recruited into lung tissues in GSDMD-/- mice, related to the release of CXCL1 and CXCL2 regulated by p65 phosphorylation. In further study, neutrophils of WT and GSDMD-/- mice were isolated and treated with SEZ (multiplicity of infection, MOI = 10, 4 h). The absence of GSDMD alleviated the death of neutrophils, in addition, GSDMD deficiency could promote translocation of p65 from the cytoplasm into the nucleus in neutrophil, which may contribute to the release of IL-1ß and TNF-α. This study demonstrated a novel function of GSDMD in host immune response to SEZ invading, indicating that GSDMD deficiency ameliorated SEZ infection through enhancing neutrophil accumulation into infected site, and activating NF-κB pathway in neutrophil to release cytokines against SEZ. Our study suggested that inhibition of host GSDMD may be an effective method against SEZ.

A case of bacteremia and pneumonia caused by Streptococcus equi subspecies equi infection in a 70-year-old female following horse exposure in rural Wyoming.

BACKGROUND: The occurrence of zoonotic infections following an animal exposure continues to be an important consideration for all patients, especially those within agricultural communities. Streptococcus equi subspecies equi (S. equi subsp. equi) is a bacteria known to cause a common infection called 'Strangles' in horses. This article highlights a new case of pneumonia and bacteremia in a patient caused by S. equi subsp. equi following strangles exposure in a horse. Rarely has there been reported horse to human transmission of subsp. equi. CASE PRESENTATION: A 70-year-old woman attended a rural emergency department with complaints of dry heaving, fever, chills, shakes, and nausea and presented with a cough. She had undergone a screening colonoscopy two days prior with no other significant medical history. The patient had computed tomography (CT) evidence of a pneumonia and positive blood cultures growing S. equi subsp. equi consistent with bacteremia. The patient later disclosed the recent passing of her horse following its sudden illness six days prior to her emergency department presentation. She had cuddled and kissed the horse prior to its death. The patient was treated with IV lactated ringers during the initial evaluation and admission and also received IV piperacillin-tazobactam 4.5 g every eight hours intravenously during her hospital stay. She was transitioned to an oral antibiotic on discharge. Subsequent blood cultures drawn the day after discharge were negative for S. equi subsp. equi, indicating successful treatment of her bacteremia. CONCLUSIONS: This report discusses an atypical presentation of S. equi subsp. equi infection in an otherwise healthy individual, manifesting as early sepsis, pneumonia, and bacteremia. The patient likely developed this infection following direct contact exposure to her horse who had died from presumed strangles a few days prior to her symptom onset. This case highlights the importance of investigating potential exposures to S. equi subsp. equi in rural areas, areas where farming and ranching are prevalent, particularly among individuals working with horses. It is especially important to acknowledge high risk populations such as immunocompromised individuals with signs and symptoms of meningitis or bacteremia.

Comprehensive review on biosynthesis of hyaluronic acid with different molecular weights and its biomedical applications.

Hyaluronic acid (HA), an anionic and nonsulfated glycosaminoglycan, is the main structural component of various tissues and plays an important role in various biological processes. Given the promising properties of HA, such as high cellular compatibility, moisture retention, antiaging, proper interaction with cells, and CD44 targeting, HA can be widely used extensively in drug delivery, tissue engineering, wound healing, and cancer therapy. HA can obtain from animal tissues and microbial fermentation, but its applications depend on its molecular weight. Microbial fermentation is a common method for HA production on an industrial scale and S. zooepidemicus is the most frequently used strain in HA production. Culture conditions including pH, temperature, agitation rate, aeration speed, shear stress, dissolved oxygen, and bioreactor type significantly affect HA biosynthesis properties. In this review all the HA production methods and purification techniques to improve its physicochemical and biological properties for various biomedical applications are discussed in details. In addition, we showed that how HA molecular weight can significantly affect its properties and applications.

Conservation of vaccine antigen sequences encoded by sequenced strains of Streptococcus equi subsp. equi.

BACKGROUND: Streptococcus equi subspecies equi (S equi) is the cause of Strangles, one of the most prevalent diseases of horses worldwide. Variation within the immunodominant SeM protein has been documented, but a new eight-component fusion protein vaccine, Strangvac, does not contain live S equi or SeM and conservation of the antigens it contains have not been reported. OBJECTIVE: To define the diversity of the eight Strangvac antigens across a diverse S equi population. STUDY DESIGN: Genomic description. METHODS: Antigen sequences from the genomes of 759 S equi isolates from 19 countries, recovered between 1955 and 2018, were analysed. Predicted amino acid sequences in the antigen fragments of SEQ0256(Eq5), SEQ0402(Eq8), SEQ0721(EAG), SEQ0855(SclF), SEQ0935(CNE), SEQ0999(IdeE), SEQ1817(SclI) and SEQ2101(SclC) in Strangvac and SeM were extracted from the 759 assembled genomes and compared. RESULTS: The predicted amino acid sequences of SclC, SclI and IdeE were identical across all 759 genomes. CNE was truncated in the genome of five (0.7%) isolates. SclF was absent from one genome and another encoded a single amino acid substitution. EAG was truncated in two genomes. Eq5 was truncated in four genomes and 123 genomes encoded a single amino acid substitution. Eq8 was truncated in three genomes, one genome encoded four amino acid substitutions and 398 genomes encoded a single amino acid substitution at the final amino acid of the Eq8 antigen fragment. Therefore, at least 1579 (99.9%) of 1580 amino acids in Strangvac were identical in 743 (97.9%) genomes, and all genomes encoded identical amino acid sequences for at least six of the eight Strangvac antigens. MAIN LIMITATIONS: Three hundred and seven (40.4%) isolates in this study were recovered from horses in the UK. CONCLUSIONS: The predicted amino acid sequences of antigens in Strangvac were highly conserved across this collection of S equi.

Gasdermin D protects against Streptococcus equi subsp. zooepidemicus infection through macrophage pyroptosis.

Streptococcus equi subsp. zooepidemicus (S. zooepidemicus, SEZ) is an essential zoonotic bacterial pathogen that can cause various inflammation, such as meningitis, endocarditis, and pneumonia. Gasdermin D (GSDMD) is involved in cytokine release and cell death, indicating an important role in controlling the microbial infection. This study investigated the protective role of GSDMD in mice infected with SEZ and examined the role of GSDMD in peritoneal macrophages in the infection. GSDMD-deficient mice were more susceptible to intraperitoneal infection with SEZ, and the white pulp structure of the spleen was seriously damaged in GSDMD-deficient mice. Although the increased proportion of macrophages did not depend on GSDMD in both spleen and peritoneal lavage fluid (PLF), deficiency of GSDMD caused the minor release of the pro-inflammatory cytokines interleukin-1ß (IL-1ß) and interleukin-18 (IL-18) during the infection in vivo. In vitro, SEZ infection induced more release of IL-1ß, IL-18, and lactate dehydrogenase (LDH) in wild-type macrophages than in GSDMD-deficient macrophages. Finally, we demonstrated that pore formation and pyroptosis of macrophages depended on GSDMD. Our findings highlight the host defense mechanisms of GSDMD against SEZ infection, providing a potential therapeutic target in SEZ infection.

Tumor necrosis factor signaling during equine placental infection leads to pro-apoptotic and necroptotic outcomes.

Ascending placentitis is the leading cause of abortion in the horse. The pleiotropic cytokine tumor necrosis factor (TNF) is an upstream regulator of this disease, but little is understood regarding its function in pregnancy maintenance or placental infection. To assess this, RNA sequencing was performed on chorioallantois and endometrium of healthy pregnant mares at various gestational lengths (n = 4/gestational age), in addition to postpartum chorioallantois, and diestrus endometrium to assess expression of TNF, TNFR-1, and TNFR-2. Additionally, ascending placentitis was induced via trans-cervical inoculation of S. equi spp. zooepidemicus in pregnant mares (n = 6 infected / n = 6 control) and tissues and serum were collected to evaluate TNF-related transcripts. IHC was performed to confirm protein localization of TNFR-1 and TNFR-2. In healthy pregnancy, TNFR-1 appears to be the predominant TNF-related receptor. Following induction of disease, TNF concentrations increased in maternal serum, but expression did not alter at the tissue level. While both TNFR-1 and TNFR-2 increased following induction of disease, alterations in downstream pathways indicate that TNFR-1 is the dominant receptor in ascending placentitis, and is primarily activated within the chorioallantois, with minimal signaling occurring within the endometrium. In conclusion, TNF appears to be involved in the pathophysiology of ascending placentitis. An increase in this cytokine during disease progression is believed to activate TNFR-1 within the chorioallantois, leading to various pro-apoptotic and necroptotic outcomes, all of which may signal for fetal demise and impending abortion.

Retrospective study of pneumonia in non-racing horses in California.

Pneumonia is a significant disease of horses. Although pneumonia has traditionally been studied in racehorses, little information is available for non-racing horses. Non-racing horses that died with pulmonary lesions (n = 156) were available from cases submitted for autopsy from January 2015 to June 2020. Bronchopneumonia (35%), interstitial pneumonia (29%), embolic pneumonia (21%), granulomatous pneumonia (13%), and pleuritis (2%) were observed in the examined horses. Seventy-four horses died or were euthanized because of pulmonary diseases, and 82 horses died or were euthanized because of non-pulmonary causes but had lung lesions. Of the horses that died from pulmonary causes, the most common finding was bronchopneumonia, with abscesses and/or necrosis in the cranioventral aspect of the lung. Bacteria isolated from cases of bronchopneumonia were Streptococcus equi subsp. zooepidemicus (48.5%), Klebsiella pneumoniae (12.1%), and Actinobacillus equuli subsp. haemolyticus (9.1%). The most common extrapulmonary lesions responsible for death in horses that also had lesions in the lung were mainly in the gastrointestinal system (30%), multiple systems (septicemia and/or toxemia; 27%), and musculoskeletal system (12%). The main postmortem findings in cases of bronchopneumonia of non-racing horses were similar to those reported previously in racehorses. However, some non-racing horses also had interstitial and granulomatous pneumonia, patterns not described previously in racehorses in California, likely as a result of the inclusion of extended age categories for non-racing horses. We also found that the equine lung was frequently affected in cases of sepsis and gastrointestinal problems of infectious origin.

Bacteriemia por Streptococcus equi subespecie zooepidemicus en un binomio madre hijo / Streptococcus equi subspecies zooepidemicus bacteremia in a mother-child binomial

Resumen Streptococcus equi subespecie zooepidemicus es una cocácea grampositiva, p-hemolítica, considerada parte de la microbiota de los equinos y un patógeno oportunista en otros animales. La infección en humanos es poco frecuente, pero suele manifestarse como cuadros graves. Se ha asociado al contacto con animales, especialmente caballos, y al consumo de productos lácteos no pasteurizados. Presentamos el caso de una bacteriemia en un binomio madre-hijo por este agente, asociado al consumo de quesos artesanales. Pese a que la penicilina es el tratamiento de elección, la recién nacida fue tratada en forma exitosa con ampicilina y la madre con ceftriaxona. Ninguna de ellas presentó complicaciones asociadas a la bacteriemia. A nuestro conocimiento, este es el primer reporte de infección connatal por este agente.

Abstract Streptococcus equi subspecies zooepidemicus is a Gram-positive, P-hemolytic coccus considered part of the commensal flora in horses and an opportunistic pathogen in other animals. Infection in humans is rare, but it usually manifests as serious symptoms, it has been associated with contact with animals, especially horses, and the consumption of unpasteurized dairy products. In this report we describe a case of bacteremia of the mother-child binomial by this agent, associated with the consumption of artisan cheeses. Although penicillin is the treatment of choice, the newborn was successfully treated with ampicillin and the mother with ceftriaxone, none of them presented complications associated with bacteremia. To our knowledge, this is the first report of connatal infection by this agent.

The clinical and histopathologic effects of potentiated chlorhexidine in the upper respiratory tract of horses.

OBJECTIVE: To describe the bactericidal and fungicidal properties of a 0.0005% chlorhexidine (CHD) solution potentiated with EDTA-Tris buffers (CHD-EDTA-Tris) and evaluate the safety of 0.0005% CHD-EDTA-Tris in the upper respiratory tract (URT) of normal horses. STUDY DESIGN: Clinical, prospective study. ANIMALS: Eight healthy, skeletally mature horses. METHODS: In vitro-serial dilutions of CHD-EDTA-Tris and EDTA-Tris alone were evaluated for bactericidal and fungicidal activity against Aspergillus fumigatus, Escherichia coli, Staphylococcus aureus, Streptococcus equi subspecies ssp. equi, Streptococcus equi ssp. zooepidemicus, and Pseudomonas aeruginosa. In vivo-eight healthy horses were topically treated twice with 30 ml of 0.0005% CHD-EDTA-Tris. Mucosal samples from each location were evaluated for the presence of inflammation or pathologic lesions. RESULTS: Solutions containing CHD were superior in fungal and bacterial killing to those without. In vitro-a 0.005% CHD-EDTA-Tris was 100% effective against all bacterial and fungal species evaluated, while a 0.0005% CHD-EDTA-Tris was less efficacious against A. fumigatus and S. equi ssp. equi. In vivo-a 0.0005% CHD-EDTA-Tris did not cause any clinical, gross, or histologic abnormalities when topically applied to the equine URT. CONCLUSIONS: A 0.0005% CHD-EDTA-Tris was highly effective for killing of common bacterial and fungal isolates in the equine upper respiratory tract. Short-term topical treatment of the equine URT with dilute CHD did not cause gross or histological inflammation in the tissue. CLINICAL SIGNIFICANCE: A 0.0005% CHD solution with EDTA-Tris should be considered for treatment of clinically relevant inflammatory or infectious conditions or in the URT of the horse.

Sucrose-modified iron nanoparticles for highly efficient microbial production of hyaluronic acid by Streptococcus zooepidemicus.

Nanoparticles (NPs) were hypothesized to enhance fermentation processes and assist microorganisms in producing valuable biopolymers. Donors of trace iron, i.e., FeSO4·7H2O, zero-valence iron nanoparticles (Fe NPs), and ferric oxide nanoparticles (α-Fe2O3 NPs), were tested to study the impact on hyaluronic acid (HA) production. The bioprocess with the addition of 30 mg/L Fe NPs produced higher HA than the other groups. However, Fe NPs were limited by the synergistic effect of geomagnetism and high surface energy, resulting in obvious agglomeration behavior. To address this, we developed novel sucrose-modified iron nanoparticles (SM-Fe NPs), which showed effective improvement of dispersion and agglomeration. Concerning the SM-Fe NP additives, an adequate supply of nutrients and trace elements provided sufficient substrates and energy for the reproduction of Streptococcus zooepidemicus. Furthermore, the highest HA production with the addition of 30 mg/L SM-Fe NPs was 0.226 g/L, and the dry weight of the produced HA increased 3.28 times compared with the control group (0.069 g/L). This work significantly improved HA production and presented promising opportunities for industrial production.

Modelagem farmacocinética/farmacodinâmica do florfenicol para o tratamento da adenite equina por meio da simulação de Monte Carlo / Pharmacokinetic/pharmacodynamic modeling of florfenicol for the treatment of equine adenitis using Monte Carlo simulation

O objetivo deste trabalho foi avaliar a eficácia do florfenicol na dose usualmente empregada em equinos de 22 mg/kg pelas vias intravenosa, intramuscular e oral para o tratamento de adenite equina por Streptococcus equi. subsp. equi, usando a modelagem farmacocinética/farmacodinâmica (PK/PD – Pharmacokinetic/Pharmacodynamic) e a simulação de Monte Carlo. Foi realizada uma simulação de Monte Carlo a partir dos parâmetros PK, logo depois, efetuou-se a modelagem PK/PD para determinar as taxas de eficácia do antimicrobiano para o tratamento dessa infecção bacteriana, de acordo com o valor da concentração inibitória mínima (CIM), em um intervalo de CIM de 0,125 – 4 μg/mL. Pela via intravenosa, a probabilidade de erradicação bacteriana foi de 100% para CIM até 0,5 μg/mL e efeito bacteriostático com probabilidades de 99% e 80% para CIMs de 2 e 4 μg/mL, respectivamente. Já pelas vias intramuscular e oral a probabilidade de se atingir o índice de erradicação bacteriológica foi de 100% para CIM de até 0,5 μg/mL, contudo, atinge valores de 80% e 81%, respectivamente, para CIM de 1 μg/mL considerando o efeito bactericida (p<0,01). Portanto, através desse estudo é evidenciado a eficácia do florfenicol até a CIM de 0,5 μg/mL para as três vias de administração citadas, entretanto, para CIMs superiores a esse valor, é imprescindível o ajuste da dose farmacológica, evitando falhas na terapêutica e possível resistência microbiana.

The objective of this study was to evaluate the efficacy of florfenicol at the dose usually used in horses of 22 mg/kg by intravenous, intramuscular and oral routes for the treatment of equine adenitis caused by Streptococcus equi. subsp. equi, using Pharmacokinetic/Pharmacodynamic (PK/PD) modeling and Monte Carlo simulation. A Monte Carlo simulation was performed from the PK parameters, then PK/PD modeling was performed to determine the antimicrobial efficacy rates for the treatment of this bacterial infection, according to the minimum inhibitory concentration (MIC) value, in a MIC range of 0.125 - 4 μg/mL. Intravenously, the probability of bacterial eradication was 100% for MICs up to 0.5 μg/mL, and the bacteriostatic effect was 99% and 80% for MICs of 2 and 4 μg/mL, respectively. However, for the intramuscular and oral routes, the probability of reaching the bacteriologic eradication index was 100% for MICs of up to 0.5 μg/mL, however, it reaches values of 80% and 81%, respectively, for MICs of 1 μg/mL considering the bactericidal effect (p<0.01). Therefore, through this study the efficacy of florfenicol is evidenced up to the MIC of 0.5 μg/mL for the three routes of administration cited, however, for MICs higher than this value, it is essential to adjust the pharmacological dose, avoiding failures in therapy and possible microbial resistance.

Glomerulonephritis after contact with a horse. / Glomerulonefritt etter kontakt med hest.

BACKGROUND: Zoonoses are important to consider when humans become ill after being in contact with animals. In such cases thorough patient history is crucial, especially when infections have an unclear cause. We present a patient with infection-associated glomerulonephritis, where a horse was the probable source of infection. CASE PRESENTATION: A young woman was admitted to the district general hospital in Vestfold, Norway, with infection and acute kidney failure. Renal biopsy suggested glomerulonephritis, and nasopharyngeal culture taken at admission detected Streptococcus equi. It emerged that the patient had daily contact with horses. INTERPRETATION: As Streptococcus equi is not part of normal human flora and the clinical signs were compatible with infection-associated glomerulonephritis, it was considered a probable causal link between the microbial finding and diagnosis. The source of infection was one of the horses.

Effects of srtA variation on phagocytosis resistance and immune response of Streptococcus equi.

Strangles, which is caused by Streptococcus equi subspecies equi (S. equi), is one of the most prevalent equine infectious diseases with worldwide distribution and leads to serious economic loss in the horse industry. Sortase A (srtA) is a transpeptidase that anchors multiple virulence-associated surface proteins to the cell surface of S. equi. srtA plays a major role in S. equi infection and colonization of the host cell. In this study, we aimed to investigate the effects of srtA mutation on the phagocytic activity and immunogenicity of S. equi. The point-mutated recombinant sortases, including srtA-HT1112 (I88V), srtA-5012 (R147G), and srtA-ZZM17 (control), were expressed, purified, and used to immunize the mouse models. Phagocytic activity was assessed using equine polymorphonuclear cells, whereas opsonophagocytic function and adherence inhibition were measured using the antiserum of these mutants. Mouse serum antibody, bacterial load, and weight gain were also measured. The srtA-HT1112 (I88V) mutant showed significantly enhanced antiphagocytic capability, and its antiserum exhibited increased adherence inhibition activity. In addition, the srtA-HT1112 (I88V) mutant presented the highest lung bacterial load and lowest protection rate (50%) after the challenge with S. equi ZZM17. The srtA-5012 (R147G) mutant exhibited a high IgG2a level and protection rate (62.5%-75%) and the lowest lung bacterial load. These results indicate that the I88V mutation is associated with a high antiphagocytic activity, whereas R147G mutation is associated with the decreased lung bacterial load. Our findings may be useful for the evaluation and development of vaccines.

Interleukin-6 pathobiology in equine placental infection.

PROBLEM: Ascending placentitis is the leading cause of abortion in the horse. Interleukin (IL)-6 is considered predictive of placental infection in other species, but little is understood regarding its role in the pathophysiology of ascending placentitis. METHOD OF STUDY: Sub-acute ascending placentitis was induced via trans-cervical inoculation of S zooepidemicus, and various fluids/serum/tissues collected 8 days later. Concentrations of IL-6 were detected within fetal fluids and serum in inoculated (n = 6) and control (n = 6) mares. RNASeq was performed on the placenta (endometrium and chorioallantois) to assess transcripts relating to IL-6 pathways. IHC was performed for immunolocalization of IL-6 receptor (IL-6R) in the placenta. RESULTS: IL-6 concentrations increased in allantoic fluid following inoculation, with a trend toward an increase in amniotic fluid. Maternal serum IL-6 was increased in inoculated animals, while no changes were noted in fetal serum. mRNA expression of IL-6-related transcripts within the chorioallantois indicates that IL-6 is activating the classical JAK/STAT pathway, thereby acting as anti-inflammatory, anti-apoptotic, and pro-survival. The IL-6R was expressed within the chorioallantois, indicating a paracrine signaling pathway of maternal IL-6 to fetal IL-6R. CONCLUSION: IL-6 plays a crucial role in the placental response to induction of sub-acute equine ascending placentitis, and this could be noted in amniotic fluid, allantoic fluid, and maternal serum. Additionally, IL-6 is acting as anti-inflammatory in this disease, potentially altering disease progression, impeding abortion signals, and assisting with the production of a viable neonate.

Immunogenicity of Streptococcus equi subsp. equi recombinant SeM protein and bacterin in mice / Imunogenicidade da proteína recombinante SeM de Streptococcus equi subsp. equi e da bacterina em camundongos

The infection caused by Streptococcus equi, known as strangles, affects the respiratory system of horses, causing high morbidity and rapid spread among the herd. Bacterin vaccines, composed of inactivated whole cells of S. equi, have variable efficacy and duration. Infected animals produce specific antibodies against SeM, the immunodominant antigen of S. equi. This makes it a promising target for vaccine development. In this context, the objective of this work was to evaluate a vaccine combining S. equi bacterin and recombinant SeM protein. Mice were vaccinated with bacterin (S. equi ~1.2 × 108CFU/ml); rSeM protein (20μg); bacterin-rSeM combination; or PBS (Control Group) and challenged with a suspension of S. equi, containing 10 × LD50. All vaccinated mice survived the challenge and produced anti-rSeM and anti-S. equi antibodies, which were assessed by indirect ELISA. The Control Group reached endpoint criteria 96 h after infection. These results demonstrate that a vaccine combining the S. equi bacterin with rSeM protein protects mice against strangles. This combination vaccine could potentially protect horses and overcome the limitations of currently available strangle vaccines.(AU)

A infecção causada por Streptococcus equi, denominada adenite, atinge o sistema respiratório de equinos, causando alta morbidade e rápida disseminação entre o rebanho. Vacinas bacterinas, compostas de células inteiras inativadas de S. equi apresentam eficácia e duração variáveis. Animais infectados apresentam anticorpos específicos à proteína SeM, antígeno imunodominante de S. equi, o que a torna um alvo promissor para o desenvolvimento de vacinas. Neste contexto, o objetivo deste trabalho foi avaliar uma vacina baseada na administração simultânea da bacterina e da proteína SeM recombinante. Camundongos foram vacinados com a bacterina (S. equi ~1.2 × 108CFU/ml); a proteína rSeM (20μg); a bacterina e rSeM simultaneamente; ou PBS (Grupo Controle) e, posteriormente, foram desafiados com uma suspensão de S. equi contendo 10 × LD50. Todos os animais vacinados apresentaram anticorpos anti-rSeM e contra S. equi, avaliados através de ELISA indireto, e mantiveram-se e sobreviveram ao desafio letal. O Grupo Controle atingiu critérios de endpoint 96 h após a infecção. Estes resultados demonstram que uma vacina constituída de células inteiras de S. equi com rSeM protege camundongos contra adenite, sugerindo a capacidade de proteção a equinos e, possivelmente, superando as limitações das vacinas contra adenite atualmente disponíveis.(AU)

Films Based on Blends of Polyvinyl Alcohol and Microbial Hyaluronic Acid

Abstract The aims of this work were to produce hyaluronic acid (HA) by Streptococcus zooepidemicus ATCC 39920 in a low cost sugarcane molasses fermentation medium and to employ the produced HA to obtain films blends based on polyvinyl alcohol (PVA). The films were produced using solution casting method and they were characterized according to their microstructure, mechanical and barrier properties. HA was added in different concentrations (0, 5, 10 and 15% (w/w)), and glycerol was used as a plasticizer (25 g/100 g solids). All formulations resulted in easily manipulated films with good appearance. The addition of HA on PVA films increased their thermal stability, solubility, swelling index, water vapor permeability and elongation. Microbial HA sample combined with PVA showed to be a promising material to biomedical application, and an addition between 5 and 10% (w/w) was sufficient to improve PVA films properties.

Cervical vertebral osteomyelitis secondary to Streptococcus equi infection in an adult horse - case report / Osteomielite vertebral cervical secundária à infecção por Streptococcus equi em um cavalo adulto - relato de caso

A 15-year-old, mixed breed, male horse was attended with a history of multiple abscesses in the cervical region with a three-year evolution. Upon admission, three fistulous tracts with drainage of purulent secretions in the cervical region, low body score, restriction of cervical movements, and painful sensitivity to palpation were observed. The horse was diagnosed with osteomyelitis secondary to Streptococcus equi infection. The initial treatment was antibiotic therapy and local curative. Owing to the lack of response, surgical debridement was performed. An initial favorable response was observed; however, after 4 months, drainage recurred, and the animal was euthanized. A post-mortem computed tomography scan was performed to obtain details of the injury. Cervical osteomyelitis is rare, and its occurrence through hematogenous spread in adult horses and the tomographic findings had not been reported previously. The long period of evolution, difficulty in performing an aggressive debridement, and the presence of multi-drug resistant bacteria contributed to the negative outcome.(AU)

Um equino macho, sem raça definida, de 15 anos de idade, foi atendido com histórico de múltiplos abscessos cervicais com evolução de três anos. Na admissão, foram observados: três trajetos fistulosos com drenagem de material purulento na região cervical; baixo escore corporal; restrição de movimentos cervicais; e sensibilidade dolorosa à palpação da região. Foi diagnosticada osteomielite vertebral cervical secundária à infecção por Streptococcus equi. O tratamento inicial consistiu na administração de antibióticos e curativo local. Na ausência de resposta à terapia, realizou-se o debridamento cirúrgico. Inicialmente, obteve-se uma resposta favorável, entretanto, após quatro meses, houve recidiva da lesão e o animal foi submetido à eutanásia. Realizou-se tomografia computadorizada no post mortem para detalhamento da lesão. A osteomielite vertebral cervical é rara, e sua ocorrência por meio de disseminação hematógena em animais adultos não foi previamente reportada. O longo período de evolução, aliado à dificuldade de realização de um debridamento agressivo, e a característica multirresistente do agente etiológico contribuíram para o desfecho negativo do caso.(AU)

Artritis séptica por Streptococcus equi: reporte de un caso y revisión de la literatura / Septic arthritis due to Streptococcus equi: a case report and review of the literatura

En humanos las infecciones producidas por Streptococcus equi son de rara ocurrencia, tienen una amplia variedad de formas de presentación, incluyendo compromiso articular, el cual ha sido pocas veces descrito en humanos y aún menos en pacientes inmunocompetentes. En este artículo se presenta un caso de artritis séptica por S. equi que ocurrió por una exposición ocupacional en un paciente inmunocompetente y la revisión de la literatura relacionada.

Human infections caused by Streptococcus equi are rare, have a wide variety of forms of presentation, including joint involvement, which has been rarely described in humans and even less in immunocompetent patients. In this article we present a septic arthritis case due to S. equi that occurred due to an occupational exposure in an immunocompetent patient, and a review of the related literature as well. The publication of this case report was accepted by the institutional ethics committee and the consent signed by the patient was obtained.

Streptococcus equi subsp. zooepidemicus and 'Neighbourhood syndrome' -extra-orbitocranial rhinosinusitis with reversible sudden loss of vision- a case report.

BACKGROUND: Rhinosinusitis is a common condition which may present with complications commonly involving the orbit and the intracranial space. Loss of vision in the absence of clinical or radiological signs of involvement of the orbit and intracranium is rare and carries a high morbidity rate. Streptococcus equi subspecies zooepidemicus is not a well-documented cause of paranasal sinus infection. CASE PRESENTATION: We present a case of a 16 year old female patient who had unilateral loss of vision with signs of retrobulbar optic neuritis and no other neurological signs. We isolated an unusual organism- Streptococcus equi subspecies zooepidemicus from the maxillary sinus. Emergency endoscopic sinus surgery and antibiotic treatment resulted in complete reversal of the loss of vision. CONCLUSION: The presence of paranasal sinus disease in association with loss of vision even in the absence of a clear link between the two should be treated as an emergency with surgical drainage and or appropriate antibiotic therapy. In patients presenting with suspected inflammatory orbital involvement, imaging of the orbit and paranasal sinuses should be considered early.