RESUMEN
The response of Alnus glutinosa to Frankia alni ACN14a is driven by several sequential physiological events from calcium spiking and root-hair deformation to the development of the nodule. Early stages of actinorhizal symbiosis were monitored at the transcriptional level to observe plant host responses to Frankia alni. Forty-two genes were significantly upregulated in inoculated compared with noninoculated roots. Most of these genes encode proteins involved in biological processes induced during microbial infection, such as oxidative stress or response to stimuli, but a large number of them are not differentially modulated or downregulated later in the process of nodulation. In contrast, several of them remained upregulated in mature nodules, and this included the gene most upregulated, which encodes a nonspecific lipid transfer protein (nsLTP). Classified as an antimicrobial peptide, this nsLTP was immunolocalized on the deformed root-hair surfaces that are points of contact for Frankia spp. during infection. Later in nodules, it binds to the surface of F. alni ACN14a vesicles, which are the specialized cells for nitrogen fixation. This nsLTP, named AgLTP24, was biologically produced in a heterologous host and purified for assay on F. alni ACN14a to identify physiological effects. Thus, the activation of the plant immunity response occurs upon first contact, while the recognition of F. alni ACN14a genes switches off part of the defense system during nodulation. AgLTP24 constitutes a part of the defense system that is maintained all along the symbiosis, with potential functions such as the formation of infection threads or nodule primordia to the control of F. alni proliferation. [Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
Asunto(s)
Frankia , Raíces de Plantas , Frankia/fisiología , Simbiosis/genética , Fijación del NitrógenoRESUMEN
We report the case of a 10-year-old girl with a painless slowly growing mass that had developed over the course of 2 years in the left submandibular area. Physical examination revealed a firm painless submandibular mass with no other associated signs. Ultrasound graphics were in favor of a sebaceous cyst. Fine-needle aspiration and magnetic resonance images (MRI) concluded to a pleomorphic adenoma of the submandibular gland. The patient underwent left submandibulectomy. Histopathological examination confirmed the diagnosis of pleomorphic adenoma arising from the submandibular gland. The postoperative course was uneventful. Pleomorphic adenoma of the submandibular gland represents a diagnostic and therapeutic dilemma in children. Preoperative evaluation, including MRI and fine-needle aspiration, is recommended. Total submandibulectomy is also recommended to minimize recurrences and to avoid malignant transformation.
Asunto(s)
Adenoma Pleomórfico , Neoplasias de la Glándula Submandibular , Femenino , Humanos , Niño , Glándula Submandibular/diagnóstico por imagen , Glándula Submandibular/cirugía , Glándula Submandibular/patología , Adenoma Pleomórfico/diagnóstico por imagen , Adenoma Pleomórfico/cirugía , Neoplasias de la Glándula Submandibular/diagnóstico por imagen , Neoplasias de la Glándula Submandibular/cirugía , Cabeza/patología , Biopsia con Aguja FinaRESUMEN
OBJECTIVE: The purpose of this study was to evaluate the diagnosis circumstances, predisposing factors, investigations, and therapeutic management of retropharyngeal and parapharyngeal abscesses. METHODS: A retrospective chart review of patients diagnosed with retropharyngeal or parapharyngeal abscess from 2001 to 2021 was performed. Epidemiological characteristics, clinical signs, investigations, medical treatment, and surgical interventions were analyzed for each patient. RESULTS: A total of 30 patients with retropharyngeal or parapharyngeal abscess were identified. Computed tomography was performed in all cases, and magnetic resonance imaging was performed in three cases. Twelve patients had a "pure" retropharyngeal abscess, nine patients had a prestyloid abscess, one patient had a prestyloid abscess associated with a peritonsillar abscess, three patients had a retrostyloid abscess, and five patients had a prestyloid abscess associated with a retropharyngeal abscess or a retrostyloid abscess. The median long axis of the abscess was 42 cm. All patients received intravenous antibiotics for a median period of 8 days [4-30]. Seventeen patients required surgical trans-cervical drainage. Other patients underwent transoral or transnasal drainage. The pus culture revealed no growth in six cases, streptococcus (four cases), methicillin-sensitive Staphylococcus aureus (two cases), Klebsiella (two cases), Enterobacter (one case), Fungi (two cases), and Mycobacterium tuberculosis (a twelve-year-old boy). It was not documented in twelve cases. Histological examination revealed caseofollicular tuberculosis in a 53-year-old man. In 25 patients, no adverse events were observed during follow-up. Five patients had an unfavorable outcome. CONCLUSION: We have found an increase in the incidence of these infections in recent years. Computed tomography is the best imaging examination for the diagnosis and follow-up of retropharyngeal and parapharyngeal abscess. Early drainage and antimicrobial therapy are essential for rapid recovery and prevention of complications of these abscesses.
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Paragangliomas could be localized from the skull base to the pelvic floor. Tympanic localization represents the most common benign tumor of the middle ear. Diagnosis is based on clinical signs with a great contribution of radiology. A 40-year-old male presented with isolated tinnitus of the right ear evolving for 18 months. Examination revealed a red bulging right-sided tympanic membrane and a conductive hearing loss. Tomodensitometry and Magnetic resonance imagery showed findings in favor of a right jugular tympanic paraganglioma. The tumor was classified type B according to FISCH classification. The patient underwent surgery consisting in tympanotomy using a retro auricular access route. The postoperative course was uneventful. There was no recurrence during the one-year follow-up. Jugular tympanic paraganglioma diagnosis is guided by a combination of epidemiological, clinical and radiological features. Treatment is still not consensual, but surgery still have its indications in localized forms of head and neck paragangliomas (HNP´s).