Paulo Worm
Universidade Federal do Rio Grande do Sul, Departamento de Cirurgia, Graduate Student
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Tock Benoît-Michel. Peter Worm. Karolingische Rekognitionszeichen: Die Kanzlerzeile und ihre graphische Ausgestaltung auf den Herrscherurkunden des achten und neunten Jahrhundert. In: Bibliothèque de l'école des chartes. 2005, tome... more
Tock Benoît-Michel. Peter Worm. Karolingische Rekognitionszeichen: Die Kanzlerzeile und ihre graphische Ausgestaltung auf den Herrscherurkunden des achten und neunten Jahrhundert. In: Bibliothèque de l'école des chartes. 2005, tome 163, livraison 1. pp. 291-292
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Abscesso cerebral por Actimomyces Odontolyticus. ...
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Esthetic deformities in the human skull are a subject of concern among neurosurgical patients and neurosurgeons; they can be disfiguring and harm the... more
Esthetic deformities in the human skull are a subject of concern among neurosurgical patients and neurosurgeons; they can be disfiguring and harm the patient's social relationships. To access inner structures, neurosurgical operations require skull trepanation, a process that frequently involves loss of bone tissue and leads to esthetic problems. Satisfactory reconstruction is a challenge, and neurosurgeons search for an implant which ideally is organic and low cost and does not cause an immunological or allergic reaction. Therefore, autologous bone tissue remains the gold standard for reconstruction. To develop a technique that allows neurosurgeons to rebuild the trepanation hole with a better esthetic outcome. Craniotomy orifices in 108 patients were closed with a graft obtained from the cranial bone inner layer. In order to remove the graft a specially made trephine was used. No grafts dislocated during follow-up. Cosmetic outcomes and results seen on image examinations were favorable for this new technique when compared with others previously described in medical literature. The authors present a new and feasible trepanation reconstruction technique that allows a better esthetic outcome without increasing the surgical risk for the patient, or making the surgical procedure longer or more expensive.
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Background: The association between remote cerebellar hematoma (RCH) and spinal surgery is poorly understood and rarely reported. We present seven cases of RCH after spinal surgery. Methods: Seven patients were diagnosed with RCH... more
Background: The association between remote cerebellar hematoma (RCH) and spinal surgery is poorly understood and rarely reported. We present seven cases of RCH after spinal surgery. Methods: Seven patients were diagnosed with RCH utilizing computed tomography and/or magnetic resonance, between 2012 and 2016. Their clinical presentations, imaging data, treatment modalities, and outcome were analyzed. There were five females and two males with an average age of 55.8 ± 8.4 years. The age of onset ranged from 43 to 67 years and the time to clinical presentation ranged from 3 h to 5 days. Patients presented with: diplopia/strabismus (one patient), dysphagia/urinary incontinence (one patient), respiratory arrest (one patient), meningismus (one patient), and dysarthria (two patients), along with other symptoms/signs. Results: Three patients were successfully managed without surgery, two required external ventricular drainage, and two were treated with posterior fossa decompression plus ven...
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IntroductionThe tumor microenvironment (TME) of glioblastoma (GB) is characterized by an increased infiltration of immunosuppressive cells that attenuate the antitumor immune response. The participation of neutrophils in tumor progression... more
IntroductionThe tumor microenvironment (TME) of glioblastoma (GB) is characterized by an increased infiltration of immunosuppressive cells that attenuate the antitumor immune response. The participation of neutrophils in tumor progression is still controversial and a dual role in the TME has been proposed. In this study, we show that neutrophils are reprogrammed by the tumor to ultimately promote GB progression.MethodsUsing in vitro and in vivo assays, we demonstrate the existence of bidirectional GB and neutrophil communication, directly promoting an immunosuppressive TME. Results and discussionNeutrophils have shown to play an important role in tumor malignancy especially in advanced 3D tumor model and Balb/c nude mice experiments, implying a time- and neutrophil concentration-dependent modulation. Studying the tumor energetic metabolism indicated a mitochondria mismatch shaping the TME secretome. The given data suggests a cytokine milieu in patients with GB that favors the recrui...
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Glioblastoma (GB) is the most common and aggressive form of primary brain tumor, in which the presence of an inflammatory environment, composed mainly by tumor-associated macrophages (TAMs), is related to its progression and development... more
Glioblastoma (GB) is the most common and aggressive form of primary brain tumor, in which the presence of an inflammatory environment, composed mainly by tumor-associated macrophages (TAMs), is related to its progression and development of chemoresistance. Toll-Like Receptors (TLRs) are key components of the innate immune system and their expression in both tumor and immune-associated cells may impact the cell communication in the tumor microenvironment (TME), further modeling cancer growth and response to therapy. Here, we investigated the participation of TLR4-mediated signaling as a mechanism of induced-immune escape in GB. Initially, bioinformatics analysis of public datasets revealed that TLR4 expression is lower in GB tumors when compared to astrocytomas (AST), and in a subset of TAMs. Further, we confirmed that TLR4 expression is downregulated in chemoresistant GB, as well as in macrophages co-cultured with GB cells. Additionally, TLR4 function is impaired in those cells even following stimulation with LPS, an agonist of TLR4. Finally, experiments performed in a cohort of clinical primary and metastatic brain tumors indicated that the immunostaining of TLR4 and CD45 are inversely proportional, and confirmed the low TLR4 expression in GBs. Interestingly, the cytoplasmic/nuclear pattern of TLR4 staining in cancer tissues suggests additional roles of this receptor in carcinogenesis. Overall, our data suggest the downregulation of TLR4 expression and activity as a strategy for GB-associated immune escape. Additional studies are necessary to better understand TLR4 signaling in TME in order to improve the benefits of immunotherapy based on TLR signaling.
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Background Patients harboring an external ventricular drain (EVD) who develop signs of infection require screening for infection in the central nervous system (CNS). The cerebrospinal fluid (CSF) can be collected by the EVD or by lumbar... more
Background Patients harboring an external ventricular drain (EVD) who develop signs of infection require screening for infection in the central nervous system (CNS). The cerebrospinal fluid (CSF) can be collected by the EVD or by lumbar puncture (LP). If only one sample is analyzed, the diagnosis might be dubious or false-negative. The objective of this study was to compare the diagnosis accuracy of CNS infection of CSF samples collected from EVD and LP. Methods We conducted a transversal study where data were prospectively collected from 2016 to 2019. Patients harboring EVD with signs of infection were submitted to the CSF analysis collected by LP and EVD. Diagnosis sensibility and results correlation were analyzed using the kappa index. Results The 141 samples from LP and 141 samples from EVD were collected from 108 patients. Among the 282 samples, a total of 77 had infection. Seventy CSF samples from LP fulfilled infection criteria. However, only 32 EVD samples demonstrated infection. Among the 70 cases of infection based on the LP sample, 25 CSF samples collected from the EVD were also suggestive of infection; but in 45 patients only the CSF samples from LP met infection criteria. Seven patients had diagnosis of infection only in the EVD sample. The kappa correlation index of the results obtained from LP and EVD was 0.260 and the McNemar χ2 test was Conclusions The CSF analysis exclusive from the EVD has a low sensibility and negative predictive value. CSF collected from LP has a sensibility 2.18 times higher than EVD.
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Background Stroke is a clinical syndrome characterized by a sudden-onset neurological deficit of vascular cause. Stroke-like clinical symptoms that are later found to have nonvascular disorders have been termed stroke mimics (MIM), and... more
Background Stroke is a clinical syndrome characterized by a sudden-onset neurological deficit of vascular cause. Stroke-like clinical symptoms that are later found to have nonvascular disorders have been termed stroke mimics (MIM), and their incidence ranges from 1.3 to 25% in patients not treated with thrombolytic therapy. Eventually, intravenous thrombolysis of MIM may occur. Case Description We describe a 74-year-old woman with abrupt global aphasia who received thrombolytic therapy after the presumed diagnosis of acute ischemic stroke. She gradually improved despite the finding of an asymptomatic left temporal hematoma on the computed tomography (CT) scan. Two months later, she presented with a new focal neurological deficit and was diagnosed with a glioblastoma in the topography of the previous bleeding. Conclusion This case highlights the rare occurrence of hemorrhage after thrombolysis in patients with MIM.
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Esthetic deformities in the human skull are a subject of concern among neurosurgical patients and neurosurgeons; they can be disfiguring and harm the... more
Esthetic deformities in the human skull are a subject of concern among neurosurgical patients and neurosurgeons; they can be disfiguring and harm the patient's social relationships. To access inner structures, neurosurgical operations require skull trepanation, a process that frequently involves loss of bone tissue and leads to esthetic problems. Satisfactory reconstruction is a challenge, and neurosurgeons search for an implant which ideally is organic and low cost and does not cause an immunological or allergic reaction. Therefore, autologous bone tissue remains the gold standard for reconstruction. To develop a technique that allows neurosurgeons to rebuild the trepanation hole with a better esthetic outcome. Craniotomy orifices in 108 patients were closed with a graft obtained from the cranial bone inner layer. In order to remove the graft a specially made trephine was used. No grafts dislocated during follow-up. Cosmetic outcomes and results seen on image examinations were favorable for this new technique when compared with others previously described in medical literature. The authors present a new and feasible trepanation reconstruction technique that allows a better esthetic outcome without increasing the surgical risk for the patient, or making the surgical procedure longer or more expensive.
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Research Interests: Medicine, Prospective studies, Humans, Female, Skull, and 14 moreMale, Bone Density, Clinical Sciences, Aged, Middle Aged, Bone Marrow Transplantation, Adult, Analysis of Variance, Reproducibility of Results, X ray Computed Tomography, Craniofacial Surgery, Bone Transplantation, Craniotomy, and Reconstructive Surgical Procedures
Research Interests: Psychology, Cognitive Science, Animal Behavior, Medicine, Hippocampus, and 15 moreBrain, Animals, Object Recognition, Male, Cell Death, Brain Ischemia, Neurons, Cognitive impairment, Neuronal Death, Long Term Memory, Cerebral Blood Flow, Memory Disorders, Maze Learning, Neurosciences, and Experimental Model
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A 54-year-old woman presented with right grade 1 hemiparesis and aphasia (NIH Stroke Scale score 13) after 5 hours of initial symptoms. MRI revealed an ischemic area in left anterior cerebral artery territory and a left frontal tumor... more
A 54-year-old woman presented with right grade 1 hemiparesis and aphasia (NIH Stroke Scale score 13) after 5 hours of initial symptoms. MRI revealed an ischemic area in left anterior cerebral artery territory and a left frontal tumor (figure 1). Endovascular reperfusion was unavailable. Etiologic investigation, which included ECG, echocardiogram, routine blood analysis, renal and thyroid function, lipidogram, HIV, hepatitis and syphilis antibodies, thrombophilia markers, MRI, and cerebral angiography (figure 2), did not reveal another alteration than the mechanical compression of the artery. After 2 weeks of clinical investigation and stabilization, complete surgical resection was performed. Language symptoms improved and the patient remains in rehabilitation. Exceptionally, meningiomas can compress major cerebral arteries, resulting in transient neurologic symptoms.1 Even more rarely, they can present as a stroke, with an estimated incidence of 0.19%.2