Endometrial Status in Queens Evaluated by Histopathology Findings and Two Cytological Techniques: Low-Volume Uterine Lavage and Uterine Swabbing.

Endometritis is associated with fertility problems in many species, with endometrial biopsy being the main diagnostic tool. In feline queens, the reduced size of the uterus may make it difficult to obtain representative diagnostic samples. Endometrial cytology may represent a valuable diagnostic tool for evaluating the health status of the endometrium in queens. Fifty domestic shorthair queens were included and divided into two cytological diagnostic technique groups, the uterine lavage (UL; n = 28) and uterine swabbing (US; n = 22) groups. Cytological results were compared with histopathological and bacteriological information. Changes in the histopathological patterns were also evaluated and compared with progesterone levels to confirm previous published data. Furthermore, the results from both cytological sampling methods were compared to evaluate the utility of each method. Endometritis was ruled out in all queens by means of histology and microbiology. Leukocyte counts and red blood cell/endometrial cell ratios were significantly higher in US than UL samples. Additionally, UL sampling is less affected by blood contamination and cells are better preserved. The combination of endometrial cytology and uterine culture might be useful for evaluating the endometrial characteristics in queens. The UL evaluation method is more representative of the actual endometrial status than the US technique.

Isolation of Phage Lysins That Effectively Kill Pseudomonas aeruginosa in Mouse Models of Lung and Skin Infection.

Multidrug resistance (MDR) is rapidly increasing in prevalence among isolates of the opportunistic pathogen Pseudomonas aeruginosa, leaving few treatment options. Phage lysins are cell wall hydrolases that have a demonstrated therapeutic potential against Gram-positive pathogens; however, the outer membrane of Gram-negative bacteria prevents most lysins from reaching the peptidoglycan, making them less effective as therapeutics. Nevertheless, a few lysins from Gram-negative bacterial phage can penetrate the bacterial outer membrane with the aid of an amphipathic tail found in the molecule's termini. In this work, we took a phylogenetic approach to systematically identify those lysins from P. aeruginosa phage that would be most effective therapeutically. We isolated and performed preliminary characterization of 16 lysins and chose 2 lysins, PlyPa03 and PlyPa91, which exhibited >5-log killing activity against P. aeruginosa and other Gram-negative pathogens (particularly Klebsiella and Enterobacter). These lysins showed rapid killing kinetics and were active in the presence of high concentrations of salt and urea and under pH conditions ranging from 5.0 to 10.0. Activity was not inhibited in the presence of the pulmonary surfactant beractant (Survanta). While neither enzyme was active in 100% human serum, PlyPa91 retained activity in low serum concentrations. The lysins were effective in the treatment of a P. aeruginosa skin infection in a mouse model, and PlyPa91 protected mice in a lung infection model, making these lysins potential drug candidates for Gram-negative bacterial infections of the skin or respiratory mucosa.

A Swine Model of Selective Geographic Atrophy of Outer Retinal Layers Mimicking Atrophic AMD: A Phase I Escalating Dose of Subretinal Sodium Iodate.

PURPOSE: To establish the dose of subretinal sodium iodate (NaIO3) in order to create a toxin-induced large animal model of selective circumscribed atrophy of outer retinal layers, the retinal pigment epithelium (RPE), and photoreceptors, by spectral-domain optical coherence tomography (SD-OCT) and immunocytochemistry. METHODS: Fifteen male and female healthy Yorkshire pigs received unilateral subretinal escalating doses of NaIO3 under general anesthesia. In all the animals, volumes of 0.1 to 0.2 mL NaIO3 were injected into the subretinal space of the area centralis through a 23/38-gauge subretinal cannula. Control SD-OCTs were performed 1 and 2 months after the surgery, at which time pigs were euthanized and eyes enucleated. Globes were routinely processed for histologic and immunohistochemical evaluation. RESULTS: Spectral-domain OCT and immunohistochemistry revealed circumscribed and well-demarcated funduscopic lesions, limited to the outer retinal layers in pigs treated with 0.01 mg/mL subretinal sodium iodate. CONCLUSIONS: The swine model of a controlled area of circumscribed retinal damage, with well-delimited borders, and selectively of the outer layers of the retina presented herein shows several clinical and histologic features of geographic atrophy in AMD. Therefore, it may represent a valuable tool in the investigation of new emerging regenerative therapies that aim to restore visual function, such as stem cell transplantation or optogenetics.

Streptococcus pyogenes Sortase Mutants Are Highly Susceptible to Killing by Host Factors Due to Aberrant Envelope Physiology.

Cell wall anchored virulence factors are critical for infection and colonization of the host by Gram-positive bacteria. Such proteins have an N-terminal leader sequence and a C-terminal sorting signal, composed of an LPXTG motif, a hydrophobic stretch, and a few positively charged amino acids. The sorting signal halts translocation across the membrane, allowing sortase to cleave the LPXTG motif, leading to surface anchoring. Deletion of sortase prevents the anchoring of virulence factors to the wall; the effects on bacterial physiology however, have not been thoroughly characterized. Here we show that deletion of Streptococcus pyogenes sortase A leads to accumulation of sorting intermediates, particularly at the septum, altering cellular morphology and physiology, and compromising membrane integrity. Such cells are highly sensitive to cathelicidin, and are rapidly killed in blood and plasma. These phenomena are not a loss-of-function effect caused by the absence of anchored surface proteins, but specifically result from the accumulation of sorting intermediates. Reduction in the level of sorting intermediates leads to a return of the sortase mutant to normal morphology, while expression of M protein with an altered LPXTG motif in wild type cells leads to toxicity in the host environment, similar to that observed in the sortase mutant. These unanticipated effects suggest that inhibition of sortase by small-molecule inhibitors could similarly lead to the rapid elimination of pathogens from an infected host, making such inhibitors much better anti-bacterial agents than previously believed.

[Comparison between coproparasitological techniques for the diagnosis of helminth eggs or protozoa oocysts in dogs]. / Comparação entre técnicas coproparasitológicas no diagnóstico de ovos de helmintos e oocistos de protozoários em cães.

In this study we evaluated the frequency of enteroparasites in pet dogs and their association with age, sex and breed, as well as the efficiency of the Willis-Mollay, Faust, Sedimentation and Direct exam methods. By these methods we processed 401 fecal samples. The samples were positive in the following percentages: Ancylostoma spp. (53.1%), Toxocara canis (20.7%), Cystoisospora ohioensis (15.7%), Trichuris vulpis (3.7%), Dipylidium caninum (2.5%) and Taenia spp. (1.0%). Toxocara canis (67.3%) and C. ohioensis (47.3%) showed higher positivity in the puppies. The Willis-Mollay technique was more efficient in the diagnosis of Ancylostoma spp. and T. canis eggs. The Direct method was the least efficient. It was found that the majority of the cases of D. caninum were diagnosed by the Sedimentation method (8=2.0%), while for T. vulpis Willis-Mollay (12=3.0%) and Sedimentation (13=3.2%) were more efficient. In view of these results, we can recommend the association of Willis-Mollay and Sedimentation methods for the diagnosis of gastrointestinal helminths. Due to the elevated occurrence of Ancylostoma spp. and T. canis, which are involved in zoonotic diseases, it becomes necessary to apply more efficient prophylaxis of canine intestinal parasitosis at the City of Araçatuba, state of São Paulo.