3 resultados para dynamic capabilities of the territory


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BACKGROUND: Traumatic clival epidural hematoma is an extremely rare reported entity. CASE DESCRIPTION: We describe the case of a 26-year-old woman involved in a car accident who presented with a Glasgow Coma Scale score of 13, bilateral abducens palsy, bilateral numbness on the mandibular territory of the trigeminal nerve, and left hypoglossal palsy. Radiological examinations revealed a clival epidural hematoma. The patient was managed conservatively, with clinical improvement of her neurological condition. This is the first traumatic clival epidural hematoma reported in an adult. From a review of the literature, we found only 8 cases. CONCLUSION: The pathophysiology of these hematomas is still a subject of debate; occipitoatlantoaxial ligamentous instability may play a role in it. In one third of the cases, bilateral cranial nerve palsies were associated. Apparently, they have a benign outcome.

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Background: Differently from HIV-1, HIV-2 disease progression usually takes decades without antiretroviral therapy and the majority of HIV-2 infected individuals survive as elite controllers with normal CD4+ T cell counts and low or undetectable plasma viral load. Neutralizing antibodies (Nabs) are thought to play a central role in HIV-2 evolution and pathogenesis. However, the dynamic of the Nab response and resulting HIV-2 escape during acute infection and their impact in HIV-2 evolution and disease progression remain largely unknown. Our objective was to characterize the Nab response and the molecular and phenotypic evolution of HIV-2 in association with Nab escape in the first years of infection in two children infected at birth. Results: CD4+ T cells decreased from about 50% to below 30% in both children in the first five years of infection and the infecting R5 viruses were replaced by X4 viruses within the same period. With antiretroviral therapy, viral load in child 1 decreased to undetectable levels and CD4+ T cells recovered to normal levels, which have been sustained at least until the age of 12. In contrast, viral load increased in child 2 and she progressed to AIDS and death at age 9. Beginning in the first year of life, child 1 raised high titers of antibodies that neutralized primary R5 isolates more effectively than X4 isolates, both autologous and heterologous. Child 2 raised a weak X4-specific Nab response that decreased sharply as disease progressed. Rate of evolution, nucleotide and amino acid diversity, and positive selection, were significantly higher in the envelope of child 1 compared to child 2. Rates of R5-to-X4 tropism switch, of V1 and V3 sequence diversification, and of convergence of V3 to a β-hairpin structure were related with rate of escape from the neutralizing antibodies. Conclusion: Our data suggests that the molecular and phenotypic evolution of the human immunodeficiency virus type 2 envelope are related with the dynamics of the neutralizing antibody response providing further support for a model in which Nabs play an important role in HIV-2 pathogenesis.

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Introduction: Brachial plexus (BP) tumors are very rare tumors, with less than 800 cases been described in the literature worldwide since 1970. These tumors often present as local or radicular pain, with scant or no neurological deficits. These symptoms are shared by many other more common rheumatologic diseases, thus making their diagnosis difficult in most cases. Additionally, these tumors often present as lumps and are therefore biopsied, which carries a significant risk of iatrogenic nerve injury. Material and Methods: In this paper the authors describe their experience with the management of 5 patients with BP tumors followed up for at least 2 years. There were 4 males and 1 female. Median follow-up time was 41 ± 21 months. Average age at diagnosis was 40,0 ± 19,9 years. The most common complaints at presentation were pain and sensibility changes. All patients had a positive Tinel sign when the lesion was percussed. In all patients surgery was undertaken and the tumors removed. In 4 patients nerve integrity was maintained. In one patient with excruciating pain a segment of the nerve had to be excised and the nerve defect was bridged with sural nerve grafts. Results: Pathology examination of the resected specimens revealed a Schwannoma in 4 cases and a neurofibroma in the patient submitted to segmental nerve resection. Two years postoperatively, no recurrences were observed. All patients revealed clinical improvement. The patient submitted to nerve resection had improvement in pain, but presented diminished strength and sensibility in the involved nerve territory. Conclusion: Surgical excision of BP tumors is not a risk free procedure. Most authors suggest surgery if the lesion is symptomatic or progressing in size. If the tumor is stationary and not associated with neurological dysfunction a conservative approach should be taken.