Delayed onset vagus nerve paralysis after occipital condyle fracture in a horse.

Occipital condylar fractures (OCFs) causing delayed onset lower cranial nerve paralysis (LCNPs) are rare. We present a 7-year-old Friesian horse with delayed onset dysphagia caused by vagus nerve (CNX) paralysis and suspicion of glossopharyngeal nerve (CNIX) paralysis developed several days after a minor head injury. Endoscopic examination revealed right laryngeal hemiplegia and intermittent dorsal displacement of the soft palate. An area of submucosal hemorrhage and bulging was appreciated over the dorsal aspect of the medial compartment of the right guttural pouch. Radiological examination of the proximal cervical region showed rotation of the atlas and the presence of a large bone fragment dorsal to the guttural pouches. Occipital condyle fracture with delayed onset cranial nerve paralysis was diagnosed. Delayed onset cranial nerve paralysis causing dysphagia might be a distinguishable sign of OCF in horses. Delayed onset dysphagia after head injury should prompt equine clinicians to evaluate the condition of the atlanto-occipital articulation and skull base.

Structural Insights into Bacteriophage GIL01 gp7 Inhibition of Host LexA Repressor.

Bacteria identify and respond to DNA damage using the SOS response. LexA, a central repressor in the response, has been implicated in the regulation of lysogeny in various temperate bacteriophages. During infection of Bacillus thuringiensis with GIL01 bacteriophage, LexA represses the SOS response and the phage lytic cycle by binding DNA, an interaction further stabilized upon binding of a viral protein, gp7. Here we report the crystallographic structure of phage-borne gp7 at 1.7-Å resolution, and characterize the 4:2 stoichiometry and potential interaction with LexA using surface plasmon resonance, static light scattering, and small-angle X-ray scattering. These data suggest that gp7 stabilizes LexA binding to operator DNA via coordination of the N- and C-terminal domains of LexA. Furthermore, we have found that gp7 can interact with LexA from Staphylococcus aureus, a significant human pathogen. Our results provide structural evidence as to how phage factors can directly associate with LexA to modulate the SOS response.

Structural insight into YcbB-mediated beta-lactam resistance in Escherichia coli.

The bacterial cell wall plays a crucial role in viability and is an important drug target. In Escherichia coli, the peptidoglycan crosslinking reaction to form the cell wall is primarily carried out by penicillin-binding proteins that catalyse D,D-transpeptidase activity. However, an alternate crosslinking mechanism involving the L,D-transpeptidase YcbB can lead to bypass of D,D-transpeptidation and beta-lactam resistance. Here, we show that the crystallographic structure of YcbB consists of a conserved L,D-transpeptidase catalytic domain decorated with a subdomain on the dynamic substrate capping loop, peptidoglycan-binding and large scaffolding domains. Meropenem acylation of YcbB gives insight into the mode of inhibition by carbapenems, the singular antibiotic class with significant activity against L,D-transpeptidases. We also report the structure of PBP5-meropenem to compare interactions mediating inhibition. Additionally, we probe the interaction network of this pathway and assay beta-lactam resistance in vivo. Our results provide structural insights into the mechanism of action and the inhibition of L,D-transpeptidation, and into YcbB-mediated antibiotic resistance.

Liquen plano bucal. Presentación de un caso / Oral lichen planus. Presentation of a case

El liquen plano es una enfermedad inflamatoria, eruptiva de la piel, pruriginosa, de marcha crónica o subaguda que puede involucrar las mucosas, sobre todo la bucal. Su etiología es desconocida, se relaciona con estímulos subjetivos (estados nerviosos, depresivos). Se mencionan también como posibles causas: las infecciones, los trastornos metabólicos y endocrinos, recientemente se ha considerado que la enfermedad puede presentar una reacción de hipersensibilidad retardada. El caso clínico del presente trabajo fue una paciente de 54 años de edad, remitida por su médico de familia con antecedentes de alteraciones psicosomáticas, resultado de un estrés mantenido durante un período de tiempo prolongado. Presentaba lesión en zona de carrillos derecho e izquierdo y en cara dorsal de lengua. Se interpretó como lesión inflamatoria no infecciosa de la mucosa bucal, la cual fue biopsiadas, lo que trajo como resultado el desarrollo de un liquen plano bucal. El diagnóstico fue corroborado por el examen histopatológico. A la paciente se le realizó tratamiento en diferentes etapas con ansiolíticos e inmuno moduladores, obteniéndose resultados satisfactorios.

Lichen planus is a pruriginous, eruptive inflammatory disease of the skin, of chronic or sub acute course that may involve mucosa, mainly the oral one. Its etiology is unknown, and is related with subjective stimuli (nervous, depressive status). Infections, metabolic and endocrine disorders are also mentioned as possible causes. Recently it has been considered that this disease may present a retarded hypersensibility reaction. The current work deals with the clinical case of a female patient, aged 54 years, who was referred by her family physician with antecedents of psychosomatic disorders, as a result of stress maintained during a long time period. She had a lesion in the area of the right and left cheeks, and in the dorsal side of the tongue. It was taken as a non infectious, inflammatory lesion of the oral mucosa, from which a biopsy was obtained, resulting in the development of an oral lichen planus. The diagnosis was corroborated by histopathological examination. The patient was treated in different stages with anxiolitics and immunomodulators, achieving satisfactory results.

[Gestation in sheep after autotransplantation with cryopreserved ovarian tissue: evidence for oocyte viability after the freezing and transplantation procedures]. / Gestaciones en ovejas autotrasplantadas con tejido ovárico criopreservado: evidencia de viabilidad ovocitaria posterior al proceso de congelación y trasplante.

UNLABELLED: Freezing ovarian tissue is acquiring a greater significance due to the increase in oocyte long term survival rates, which provides young women with malignancies an alternative to preserve their fertility. OBJECTIVES: 1. Assessing the physiological viability of ovarian tissue auto-transplants. 2. Determining possible differences between the two cryoprotectors that were used: dimethyl sulfoxide (DMSO) and propanediol (PROH). DESIGN: Experimental and prospective study assessing ovarian tissue viability after freezing and auto-transplantation in eight female sheep. MATERIALS AND METHODS: A bilateral oophorectomy was performed on the sheep under general anesthesia. The ovarian cortex was dissected and frozen using either DMSO (1.5 M) or PROH (1.5) with saccharose. The thawed tissue was auto-transplanted within the following one to six months, and weekly progesterone measurements were carried out in order to assess ovarian tissue functionality. Once ovulation levels were obtained, the female sheep were continuously exposed to the male in order to obtain the gestation process. RESULTS: Ovulation activity was recovered in seven of the eight female sheep (87.5%) submitted to auto-transplants within an average period of time of 62.8 +/- 9.1 days, as evidenced by serum progesterone levels. These findings were obtained regardless of the cryoprotector used. Two gestations were obtained, and these are evolving normally, as assessed by ultrasonic methods. CONCLUSIONS: The present study shows that ovarian function is adequately restored in oophorectomized sheep using ovarian tissue auto-transplantation, and produced the first pregnancies obtained through this technique in Latin America. It is possible to assume that these results can be reproduced in women.