317 research outputs found
Prions and neuronal death
The present contribution is a Letter to the Editor (Correspondence) and, as a consequence, no abstract is available.[...
Effect of hydrogen peroxide on the oxidative burst of neutrophils in pigs and ruminants
Background and Aim: Neutrophils represent between 20% and 75% of white blood cells in animals and play a key role in an effective immune response. The generation of reactive oxygen species (ROS) is commonly referred to as an oxidative burst and is crucial under healthy and disease conditions. Interestingly, ROS are emerging as regulators of several neutrophil functions, including their oxidative burst. The present study aimed to investigate the effect of hydrogen peroxide on the oxidative burst of neutrophils, collected from domestic animal species (namely, pig, cattle, and sheep), and exposed to different stimuli. Materials and Methods: A total of 65 slaughtered animals were included in the present study: Twenty-two pigs, 21 cattle, and 22 sheep. Blood samples were collected at bleeding and neutrophils were then purified using ad hoc developed and species-specific protocols. Neutrophils were treated with hydrogen peroxide at micromolar-to-millimolar concentrations, alone, or combined with other stimuli (i.e., opsonized yeasts, and phorbol 12-myristate 13-acetate). The generation of ROS was evaluated using a luminol-derived chemiluminescence (CL) assay. For each animal species, data were aggregated and reported as mean area under curve±standard deviation. Finally, data were statistically analyzed by one-way ANOVA, followed by Tukey's post hoc test. Results: Exposure of bovine and ovine neutrophils to hydrogen peroxide alone resulted in a dose-dependent enhancement of the CL response, which was significantly stronger at its highest concentration and proved particularly prominent in sheep. Opsonized yeasts and phorbol 12-myristate 13-acetate both proved capable of stimulating the generation of ROS in all animal species under study. Hydrogen peroxide negatively modulated the oxidative burst of neutrophils after exposure to those stimuli, observed response patterns varying between pigs and ruminants. Porcine neutrophils, pre-exposed to micromolar concentrations of hydrogen peroxide, showed a decreased CL response only to opsonized yeasts. Conversely, pre-exposure to hydrogen peroxide reduced the CL response of ruminant neutrophils both to yeasts and phorbol 12-myristate 13-acetate, the effect being most prominent at 1 mM concentration. Conclusion: These results indicate that hydrogen peroxide is capable of modulating the oxidative bursts of neutrophils in a species-specific and dose-dependent manner, substantial differences existing between pigs and ruminants. Further investigation is required to fully comprehend such modulation, which is crucial for the proper management of the generation of ROS under healthy and disease conditions
A case of pulmonary tuberculosis presenting as diffuse alveolar haemorrhage: is there a role for anticardiolipin antibodies?
<p>Abstract</p> <p>Background</p> <p>Diffuse alveolar haemorrhage (DAH) has been rarely reported in association with pulmonary infections.</p> <p>Case Presentation</p> <p>We report the case of a 43 year old immunocompetent man presenting with dyspnoea, fever and haemoptysis. Chest imaging showed bilateral ground glass opacities. Microbiological and molecular tests were positive for <it>Mycobacterium tuberculosis </it>and treatment with isoniazid, rifampicin, ethambutol and pyrazinamide was successful. In this case the diagnosis of DAH relies on clinical, radiological and endoscopic findings. Routine blood tests documented the presence of anticardiolipin antibodies. In the reported case the diagnostic criteria of antiphospholipid syndrome were not fulfilled.</p> <p>Conclusions</p> <p>The transient presence of anticardiolipin antibodies in association with an unusual clinical presentation of pulmonary tuberculosis is intriguing although a causal relationship cannot be established.</p
SUMMER SORES SECONDARY TO A HOOF CRACK IN AN ANDALUSIAN STALLION
Cutaneous habronemosis in horses is caused by larvae of the spirurid nematodes Habronema microstoma and Habronema muscae. These lesions, also known as "summer sores'', are often severe and disfiguring. Although Habronema-caused lesions at the coronary grooves have been described, cases of hoof cracks with secondary summer sores have never been reported. The present case describes clinic-pathological and surgical features of a quarter crack case complicated by cutaneous habronemosis at the dermal layers. A 15-year-old, Andalusian stallion was referred to the Veterinary Teaching Hospital of the University of Teramo because of a mass of the hoof and a severe lameness. The clinical examination revealed an exuberant granulation tissue protruding from a full thickness vertical quarter crack. The mass was surgically removed, and subjected to histopathological, microbiological, and parasitological analyses. A copromicroscopic examination was also performed. The feces scored PCR positive for H. muscae, while the skin for both H. microstoma and H. muscae, thus confirming the primary role of Habronema in causing the hoof mass. This is the first description of a hoof wall crack complicated by summer sores, with simultaneous gastric habronemosis. This case confirms that a prompt diagnosis during fly activity is imperative for an efficacious treatment and a timely prevention of disfiguring summer sores
Chronic infection with non-tuberculous mycobacteria in patients with non-CF bronchiectasis: Comparison with other pathogens
Abstract Introduction The aim of this study is to compare characteristics of non-cystic fibrosis bronchiectasis (NCFBE) patients with chronic infections with non-tuberculous mycobacteria (NTM) versus those with Pseudomonas aeruginosa or other colonizations. Methods This was an observational, perspective study of consecutive NCFBE adult patients attending the outpatient bronchiectasis clinic at the San Gerardo Hospital in Monza, Italy, during 2012 and 2013. Patients with a chronic infection were included in the study and divided into three groups: those with NTM (Group A); those with P. aeruginosa (Group B); and those with other pathogens (Group C). Patients with both NTM and another pathogen were included in Group A. Comparison among the three study groups was performed using X 2 or Fisher exact test for categorical variables or Kruskal–Wallis or Mann–Whitney test for continuous variables. Results A total of 146 patients (median age 67 years, 40% males) were enrolled: 19 belonged to Group A, 34 to Group B and 93 to Group C. Within group A, 6 patients had only NTM isolation, 7 patients had NTM and P. aeruginosa co-infection and 6 patients had NTM plus another pathogen. The most common isolated pathogens among NTM was Mycobacterium avium complex (15 patients, 79%). A total of 4 patients (21%) with NTM were on active treatment. Patients affected by NTM pulmonary infection had a significantly less severe clinical, functional and radiological involvement compared with patients colonized by P. aeruginosa , see Table. Group A (NTM) n = 19 Group B ( P. aeruginosa ) n = 34 Group C (Others) n = 93 p Value ∗ p Value # p Value + Age (years), median (IQR) 70 (64–75) 74 (67–79) 66 (53–72) 0.001 0.172 0.050 Male, n (%) 8 (42) 15 (44) 36 (33) 0.660 – – BMI, median (IQR) 22 (19–26) 24 (21–25) 24 (21–27) 0.352 – – BSI, median (IQR) 5 (4–9) 12 (8.5–16) 5 (3–7) 0.001 0.001 0.090 Bhalla score, median (IQR) 21 (15–34) 36 (30.5–40.5) 16 (10.5–21.5) 0.001 0.016 0.076 Idiopathic etiology, n (%) 8 (42) 11 (32) 37 (40) 0.721 – – Post-infective etiology, n (%) 8 (42) 16 (47) 29 (31) 0.244 – – Exacerbations/y, median (IQR) 1 (0–2) 2 (1.5–3.5) 2 (1–2) 0.040 0.024 0.132 FEV1%, median (IQR) 85 (59.75–109.5) 58.5 (48.25–74) 84 (62–102) 0.002 0.010 0.857 FVC%, median (IQR) 94.5 (70–109.75) 65 (56–81.5) 88 (69.5–101.5) 0.003 0.003 0.270 ∗ Among the three groups: # Group A vs. Group B; + Group A vs. Group C; BMI: Body mass index; BSI: bronchiectasis severity index; y: year. Conclusions Colonization with P. aeruginosa seems to have the highest impact on the clinical, functional and radiological status of patients with NCFBE. No specific characteristics may help to identify NTM versus other pathogen colonizations. Thus, diagnostics for atypical mycobacteria should be performed on all patients with NCFBE, as suggested by recent international guidelines
Occurrence, antimicrobial susceptibility, and pathogenic factors of Pseudomonas aeruginosa in canine clinical samples
Background and Aim: Pseudomonas aeruginosa is a relevant opportunistic and difficult to treat pathogen due to its widespread environmental diffusion, intrinsic resistance to many classes of antimicrobials, high ability to acquire additional resistance mechanisms, and wide range of pathogenic factors. The present study aimed to investigate the prevalence of P. aeruginosa in canine clinical samples, the antimicrobial susceptibility against antipseudomonal antibiotics, and the presence of extracellular pathogenic factors of the isolates, as well as their ability to produce biofilm. Materials and Methods: Overall, 300 clinical specimens from dogs with pyoderma or abscesses (n=58), otitis (n=59), and suspected bladder infection (n=183) were analyzed by standard bacteriological methods. P. aeruginosa isolates were tested for their antimicrobial susceptibility by disk and gradient diffusion methods to determine the minimum inhibitory concentrations. The ability of the isolates to produce biofilm was investigated by a microtiter plate assay, while virulence genes coding for elastase (lasB), exotoxin A (toxA), alkaline protease (aprA), hemolytic phospholipase C (plcH), and exoenzyme S (ExoS) were detected by polymerase chain reaction method. Results: A total of 24 isolates of P. aeruginosa were found in clinical specimens (urine n=3, skin/soft tissue n=6, and ear canal n=15). No resistance was found to ceftazidime, gentamicin, aztreonam, and imipenem (IMI), while low levels of resistance were found to enrofloxacin (ENR) (4.2%) and piperacillin-tazobactam (8.3%). However, 41.7% and 29.2% of the isolates showed intermediate susceptibility to ENR and IMI, respectively. Disk and gradient diffusion methods showed high concordance. The majority of the isolates revealed a weak (33.3%) or intermediate (45.8%) ability to form biofilm, while the strong biofilm producers (20.8%) derived exclusively from the ear canal samples. All isolates (100%) were positive for lasB, aprA, and plcH genes, while exoS and toxA were amplified in 21 (87.5%) and 22 (91.7%) isolates, respectively. Conclusion: In the present study, P. aeruginosa isolates from canine clinical samples were characterized by low levels of antimicrobial resistance against antipseudomonal drugs. However, the high presence of isolates with intermediate susceptibility for some categories of antibiotics, including carbapenems which are not authorized for veterinary use, could represent an early warning signal. Moreover, the presence of isolates with strong ability to produce biofilm represents a challenge for the interpretation of the antimicrobial susceptibility profile. In addition, the high prevalence of the extracellular pathogenic factors was indicative of the potential virulence of the isolates
Congenital Oral Squamous Cell Carcinoma in a Suckling Piglet
A 3-week-old suckling piglet spontaneously died after septicemic colibacillosis. At postmortem examination, bulging and ulcerated lesions were seen, affecting the oral mucosa on the inner surface of the lower lip. After histopathological investigation, the diagnosis of congenital oral squamous cell carcinoma was made. To the best of our knowledge, this is the first case of congenital oral squamous cell carcinoma ever described. A relationship has been shown or suggested between papillomavirus infection and oral squamous cell carcinoma in humans and animals. However, next-generation sequencing study did not demonstrate any papillomavirus sequences in the case reported herein
Polymorphonuclear cells and reactive oxygen species in contagious bovine pleuropneumonia: New insight from in vitro investigations
Abstract Reactive oxygen species (ROS) are suggested to play a role in the pathogenesis of contagious bovine pleuropneumonia, a severe respiratory disorder caused by Mycoplasma mycoides subsp. mycoides ( Mmm ). The present study investigated the generation of ROS by different strains of Mmm , as well as their effect on the oxidative response of bovine neutrophils. The production of ROS was indirectly measured using a luminol-based chemiluminescence assay. Our results confirm that Mmm can produce ROS via the metabolism of glycerol, significant differences existing between African and European strains. Mmm was capable of adhering to the external surface of neutrophils. Interestingly, Mmm enhanced the respiratory burst of bovine neutrophils. This activity was particularly pronounced with the African field strain and in presence of glycerol. Taken together, our data argue in favour of a major role for neutrophils as the main source of ROS in contagious bovine pleuropneumonia
Aspergillus section fumigati pneumonia and oxalate nephrosis in a foal
Equine pulmonary aspergillosis is a rare deep mycosis often due to the hematogenous spread of hyphae after gastrointestinal tract disease. We describe herein the main clinic-pathological findings observed in a foal, which spontaneously died after showing diarrhea and respiratory distress. Necropsy and histopathological investigations allowed to diagnose pulmonary aspergillosis, which likely developed after necrotic typhlitis-colitis. Biomolecular studies identified Aspergillus section Fumigati strain as the causative agent. Notably, severe oxalate nephrosis was concurrently observed. Occasionally, oxalate nephropathy can be a sequela of pulmonary aspergillosis in humans. The present case report suggests that the renal precipitation of oxalates can occur also in horses affected by pulmonary aspergillosis and could likely contribute to the fatal outcome of the disease
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