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1.
Cureus ; 16(8): e66197, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39233954

RESUMO

In this study, we report surgical management combined with radiotherapy in two patients with typical chordoma. Different types of radiation have varied effects on chordomas when they are radiated. Classical cases display cellular atypia and fibrosis following irradiation, while necrosis and fibrosclerosis are observed after carbon ion therapy, implying that it is possible to control the tumor more effectively using carbon ion therapy with minimal side effects.

2.
Cureus ; 16(5): e61308, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38947620

RESUMO

The papillary tumor of the pineal region (PTPR) is a rare neuroepithelial tumor originating from specialized ependymocytes. It primarily affects structures within the pineal region, including the pineal gland, epithalamus, quadrigeminal cistern, and posterior wall of the third ventricle. Here, we present a series of four cases characterized by symptoms associated with obstructive hydrocephalus such as headaches, seizures, visual disturbances, gait disturbances, and Parinaud syndrome. Imaging studies revealed lesions in the pineal region, prompting surgical intervention. Histopathological examination, including biopsy and intraoperative analysis, confirmed the diagnosis of PTPR. Despite advancements, the etiology and pathogenesis of PTPR remain incompletely understood, warranting further research to refine management strategies.

3.
World Neurosurg ; 187: 19-28, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38583569

RESUMO

BACKGROUND: Ventriculoscopic neuronavigation has been described in several articles. However, there are different ventriculoscopes and navigation systems. Due to these different combinations, it is difficult to find detailed neuronavigation protocols. We describe, step-by-step, a simple method to navigate both the trajectory until reaching the ventricular system, as well as the intraventricular work. METHODS: We use a rigid ventriculoscope (LOTTA, KarlStorz) with an electromagnetic stylet (S8-StealthSystem, Medtronic). The protocol is based on a modified or 3-dimensionally printed trocar for navigating the extraventricular step and on a modified pediatric nasogastric tube for the intraventricular navigation. RESULTS: This protocol can be set up in less than 10 minutes. The extraventricular part is navigated by introducing the electromagnetic stylet inside the modified or 3-dimensionally printed trocar. Intraventricular navigation is done by combining a modified pediatric nasogastric tube with the electromagnetic stylet inside the endoscope's working channel. The most critical point is to obtain a blunt-bloodless ventriculostomy while achieving perfect alignment of all targeted structures via pure straight trajectories. CONCLUSIONS: This protocol is easy-to-set-up, avoids head rigid-fixation and bulky optical-based attachments to the ventriculoscope, and allows continuous navigation of both parts of the surgery. Since we have implemented this protocol, we have noticed a significant enhancement in both simple and complex ventriculoscopic procedures because the surgery is dramatically simplified.


Assuntos
Neuroendoscópios , Neuroendoscopia , Neuronavegação , Ventriculostomia , Fluxo de Trabalho , Humanos , Neuronavegação/métodos , Neuronavegação/instrumentação , Neuroendoscopia/métodos , Neuroendoscopia/instrumentação , Ventriculostomia/métodos , Ventriculostomia/instrumentação , Fenômenos Eletromagnéticos , Impressão Tridimensional
4.
J Ultrasound ; 27(1): 191-197, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38308121

RESUMO

PURPOSE: Surgery of deep-seated brain tumors can be challenging. Several methods have been described to facilitate transcortical approaches, including ultrasound-assisted resection. Ultrasound-guided placement of a standard ventricular catheter is a widely reported technique and has been used to approach these lesions via the transcortical route. We describe how we usually perform this useful technique to assist and enhance the transcortical resection of some deep-seated brain tumors. METHODS: Standard electromagnetic frameless navigation (S8 Neuronavigation System, Medtronic, Minneapolis, USA) was employed to focus the craniotomy and to plan the trajectory of the ventricular catheter. After dural opening, an ultrasound device (Arietta 850, Hitachi-Aloka Medical, Tokyo, Japan) was used for intraoperative ultrasound (IOUS) assessment. A ventricular catheter was placed from the cortex to the lateral wall of the tumor under direct real-time IOUS visualization to guide the further transcortical dissection. RESULTS: Transcortical transcatheter ultrasound-assisted technique involved minimal time and infrastructure requirements. There were no major technical difficulties during its use, providing confidence and improving subcortical white matter dissection by guiding the route to the tumor. CONCLUSIONS: Recent improvement of IOUS image-quality devices offers several attractive options for real-time navigation. The combination of conventional neuronavigation systems with real-time IOUS assessment during the intradural step provides a higher degree of control by improving the execution of the surgery. We hope this description may be a useful tool for some selected cases and contribute to the further enhancement and improvement of this widely used technique.


Assuntos
Neoplasias Encefálicas , Humanos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Ultrassonografia
5.
Neurochem Int ; 174: 105679, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309665

RESUMO

Down syndrome (DS) is the most common genetic disorder associated with intellectual disability. To study this syndrome, several mouse models have been developed. Among the most common is the Ts65Dn model, which mimics most of the alterations observed in DS. Ts65Dn mice, as humans with DS, show defects in the structure, density, and distribution of dendritic spines in the cerebral cortex and hippocampus. Fasudil is a potent inhibitor of the RhoA kinase pathway, which is involved in the formation and stabilization of dendritic spines. Our study analysed the effect of early chronic fasudil treatment on the alterations observed in the hippocampus of the Ts65Dn model. We observed that treating Ts65Dn mice with fasudil induced an increase in neural plasticity in the hippocampus: there was an increment in the expression of PSA-NCAM and BDNF, in the dendritic branching and spine density of granule neurons, as well as in cell proliferation and neurogenesis in the subgranular zone. Finally, the treatment reduced the unbalance between excitation and inhibition present in this model. Overall, early chronic treatment with fasudil increases cell plasticity and eliminates differences with euploid animals.


Assuntos
1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , Síndrome de Down , Humanos , Camundongos , Animais , Síndrome de Down/tratamento farmacológico , Síndrome de Down/genética , Síndrome de Down/metabolismo , Camundongos Transgênicos , Hipocampo/metabolismo , Neurônios/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL
6.
World Neurosurg ; 184: 137, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37972918

RESUMO

In recent decades, the management of middle fossa arachnoid cysts in pediatric patients has evolved significantly through the integration of novel techniques, such as the utilization of endoscopy systems1 and implementation of minimally invasive approaches like keyhole craniotomy.2,3 These cystic formations, occurring within the arachnoid membrane, may lead to neurologic impairments and raised intracranial pressure if left untreated.4 The utilization of endoscopy to aid microsurgical techniques or as a complement to them provides a level of visualization and manipulation of the cyst walls that is significantly more precise than the isolated use of a microscope.1 The keyhole craniotomy allows for reduced surgical trauma, smaller incisions, and quicker recovery times.5 In Video 1, we present the case of a 2-year-old patient with bilateral middle fossa arachnoid cysts exerting mass effect on the adjacent parenchyma. The patient was referred to our institution due to developmental delay and cognitive issues related to language and social interactions. On the basis of imaging findings and clinical correlation, we opted for a microsurgical fenestration with endoscopic inspection using a keyhole craniotomy to minimize complications and enhance the benefits of both techniques. Throughout the surgical video, tricks and considerations that contribute to the combined procedure's efficiency and ease of execution are highlighted and discussed. Postoperative images showed no complications, and the patient was discharged 3 days after surgery.


Assuntos
Cistos Aracnóideos , Hipertensão Intracraniana , Procedimentos Cirúrgicos Otológicos , Criança , Humanos , Pré-Escolar , Cistos Aracnóideos/diagnóstico por imagem , Cistos Aracnóideos/cirurgia , Endoscopia/métodos , Craniotomia/métodos , Hipertensão Intracraniana/cirurgia
7.
Front Plant Sci ; 14: 1250105, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37915512

RESUMO

Cassava is a major crop in Sub-Saharan Africa, where it is grown primarily by smallholder farmers. Cassava production is constrained by Cassava mosaic disease (CMD), which is caused by a complex of cassava mosaic begomoviruses (CMBs). A previous study showed that SEGS-1 (sequences enhancing geminivirus symptoms), which occurs in the cassava genome and as episomes during viral infection, enhances CMD symptoms and breaks resistance in cassava. We report here that SEGS-1 also increases viral disease severity in Arabidopsis thaliana plants that are co-inoculated with African cassava mosaic virus (ACMV) and SEGS-1 sequences. Viral disease was also enhanced in Arabidopsis plants carrying a SEGS-1 transgene when inoculated with ACMV alone. Unlike cassava, no SEGS-1 episomal DNA was detected in the transgenic Arabidopsis plants during ACMV infection. Studies using Nicotiana tabacum suspension cells showed that co-transfection of SEGS-1 sequences with an ACMV replicon increases viral DNA accumulation in the absence of viral movement. Together, these results demonstrated that SEGS-1 can function in a heterologous host to increase disease severity. Moreover, SEGS-1 is active in a host genomic context, indicating that SEGS-1 episomes are not required for disease enhancement.

8.
J Clin Neurosci ; 116: 39-43, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37611370

RESUMO

The extended transforaminal endoscopic approaches allows visualization and manipulation of the middle and posterior third of the III ventricle. In selected cases where the venous anatomy is favorable, the medial subchoroidal approach can be performed as an alternative to the classic transchoroidal approach (via trans-taenia fornicis) with increased protection over the fornix and without the need to sacrifice the septal vein. We present a 14-year-old male with history of Neurofibromatosis type 1 referred for two weeks of clinical evolution with headache, dizziness, gait instability and appearance of a right VI nerve palsy. Magnetic resonance imaging showed obstructive tri-ventricular hydrocephalus due to stenosis of the aqueduct of Sylvius with suspicion of an underlying tumor. An endoscopic surgical procedure was performed through a single approach with III cisternostomy and resection of the tissue that produced the stenosis. The anatomopathological diagnosis showed reactive glial tissue with no signs of malignancy. In conclusion, the medial subchoroidal approach is a plausible alternative in the endoscopic approach to the III ventricle structures in a safe and comfortable manner.


Assuntos
Doenças do Nervo Abducente , Veias Cerebrais , Hidrocefalia , Masculino , Humanos , Adolescente , Constrição Patológica , Endoscopia , Ventrículos Cerebrais , Hidrocefalia/diagnóstico por imagem , Hidrocefalia/etiologia , Hidrocefalia/cirurgia
9.
Neurosurg Focus Video ; 8(2): V5, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37089745

RESUMO

The extended transforaminal endoscopic approach allows visualization and manipulation of the third ventricle posterior structures in a safe and comfortable manner. The medial subchoroidal approach has been described as a feasible alternative to the classical transchoroidal approach. In this video, the authors present the case of a 14-year-old male with a history of neurofibromatosis type 1 who was referred to our department after presenting with headaches and diplopia for 2 weeks. Suspecting an aqueduct tumor, the authors performed an endoscopic surgical procedure through a single approach with third cisternostomy and resection of the tumor that produced the stenosis. The video can be found here: https://stream.cadmore.media/r10.3171/2023.1.FOCVID22155.

10.
Cancers (Basel) ; 15(3)2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36765559

RESUMO

With a high risk of relapse and death, and a poor or absent response to therapeutics, the triple-negative breast cancer (TNBC) subtype is particularly challenging, especially in patients who cannot achieve a pathological complete response (pCR) after neoadjuvant chemotherapy (NAC). Although the tumor microenvironment (TME) is known to influence disease progression and the effectiveness of therapeutics, its predictive and prognostic potential remains uncertain. This work aimed to define the residual TME profile after NAC of a retrospective cohort with 96 TNBC patients by immunohistochemical staining (cell markers) and chromogenic in situ hybridization (genetic markers). Kaplan-Meier curves were used to estimate the influence of the selected TME markers on five-year overall survival (OS) and relapse-free survival (RFS) probabilities. The risks of each variable being associated with relapse and death were determined through univariate and multivariate Cox analyses. We describe a unique tumor-infiltrating immune profile with high levels of lymphocytes (CD4, FOXP3) and dendritic cells (CD21, CD1a and CD83) that are valuable prognostic factors in post-NAC TNBC patients. Our study also demonstrates the value of considering not only cellular but also genetic TME markers such as MUC-1 and CXCL13 in routine clinical diagnosis to refine prognosis modelling.

11.
J Ultrasound ; 26(3): 733-741, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36642754

RESUMO

BACKGROUND: Since the introduction of ultrasonography (US) in the operating theatre in the early 1970s, intraoperative ultrasound (IOUS) has become a very useful tool for real-time neurosurgical procedures. The main limitation of US is its innately reduced capacity to penetrate the intact skull. This is the reason why most IOUS-assisted procedures are usually performed via transfontanellar or after a craniotomy or laminotomy is done. OBJECTIVE: We present a 54-year-old woman with a right optic nerve sheath meningioma, who was operated on by a right cranio-orbital approach and IOUS-assisted tumour removal. METHODS: Data concerning the anamnesis and complementary studies were obtained from the clinical history. Surgical images were obtained in the operating room during surgery. Images obtained by US were compared with the preoperative and postoperative imaging scans. IOUS imaging was also compared with the intraoperative findings. RESULTS: The correlation between US and both preoperative and postoperative studies was very high. During surgery, both transpalpebral and transperiorbital IOUS facilitated the resection with no specific technical difficulties or significant time consumption. CONCLUSION: Recent improvements in the image quality of IOUS devices offer several attractive options for real-time neuronavigation. We describe our initial experience with the IOUS-assisted technique for orbital apex tumours. In our patient transpalpebral and transperiorbital IOUS provided an excellent source of control over location and over the extent of tumour resection. We hope that this description of how we usually perform this procedure may be useful for some selected cases and contribute to the further enhancement and improvement of the technique.


Assuntos
Neoplasias Encefálicas , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Encefálicas/cirurgia , Ultrassonografia , Procedimentos Neurocirúrgicos/métodos , Neuronavegação/métodos , Imageamento por Ressonância Magnética
12.
Front Neuroanat ; 16: 851432, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464133

RESUMO

This work provides evidence of the presence of immature neurons in the human brain, specifically in the layer II of the cerebral cortex. Using surgical samples from epileptic patients and post-mortem tissue, we have found cells with different levels of dendritic complexity (type I and type II cells) expressing DCX and PSA-NCAM and lacking expression of the mature neuronal marker NeuN. These immature cells belonged to the excitatory lineage, as demonstrated both by the expression of CUX1, CTIP2, and TBR1 transcription factors and by the lack of the inhibitory marker GAD67. The type II cells had some puncta expressing inhibitory and excitatory synaptic markers apposed to their perisomatic and peridendritic regions and ultrastructural analysis suggest the presence of synaptic contacts. These cells did not present glial cell markers, although astroglial and microglial processes were found in close apposition to their somata and dendrites, particularly on type I cells. Our findings confirm the presence of immature neurons in several regions of the cerebral cortex of humans of different ages and define their lineage. The presence of some mature features in some of these cells suggests the possibility of a progressively integration as excitatory neurons, as described in the olfactory cortex of rodents.

13.
J Clin Anesth ; 80: 110752, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35405517

RESUMO

STUDY OBJECTIVE: Assess the relationship between the Enhanced Recovery After Surgery (ERAS®) pathway and routine care and 30-day postoperative outcomes. DESIGN: Prospective cohort study. SETTING: European centers (185 hospitals) across 21 countries. PATIENTS: A total of 2841 adult patients undergoing elective colorectal surgery. Each hospital had a 1-month recruitment period between October 2019 and September 2020. INTERVENTIONS: Routine perioperative care. MEASUREMENTS: Twenty-four components of the ERAS pathway were assessed in all patients regardless of whether they were treated in a formal ERAS pathway. A multivariable and multilevel logistic regression model was used to adjust for baseline risk factors, ERAS elements and country-based differences. RESULTS: A total of 1835 patients (65%) received perioperative care at a self-declared ERAS center, 474 (16.7%) developed moderate-to-severe postoperative complications, and 63 patients died (2.2%). There was no difference in the primary outcome between patients who were or were not treated in self-declared ERAS centers (17.1% vs. 16%; OR 1.00; 95%CI, 0.79-1.27; P = 0.986). Hospital stay was shorter among patients treated in self-declared ERAS centers (6 [5-9] vs. 8 [6-10] days; OR 0.82; 95%CI, 0.78-0.87; P < 0.001). Median adherence to 24 ERAS elements was 57% [48%-65%]. Adherence to ERAS-pathway quartiles (≥65% vs. <48%) suggested that patients with the highest adherence rates experienced a lower risk of moderate-to-severe complications (15.9% vs. 17.8%; OR 0.71; 95%CI, 0.53-0.96; P = 0.027), lower risk of death (0.3% vs. 2.9%; OR 0.10; 95%CI, 0.02-0.42; P = 0.002) and shorter hospital stay (6 [4-8] vs. 7 [5-10] days; OR 0.74; 95%CI, 0.69-0.79; P < 0.001). CONCLUSIONS: Treatment in a self-declared ERAS center does not improve outcome after colorectal surgery. Increased adherence to the ERAS pathway is associated with a significant reduction in overall postoperative complications, lower risk of moderate-to-severe complications, shorter length of hospital stay and lower 30-day mortality.


Assuntos
Cirurgia Colorretal , Recuperação Pós-Cirúrgica Melhorada , Adulto , Cirurgia Colorretal/efeitos adversos , Procedimentos Cirúrgicos Eletivos/efeitos adversos , Humanos , Tempo de Internação , Estudos Observacionais como Assunto , Assistência Perioperatória/métodos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos
14.
Rev Esp Geriatr Gerontol ; 57(1): 6-12, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-34924215

RESUMO

BACKGROUND AND OBJECTIVE: COVID-19 is a disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and has caused a global pandemic that we are currently suffering from. OBJECTIVE: to identify factors associated with the death of patients aged 65 years or older hospitalized for COVID-19. MATERIALS AND METHODS: Retrospective cohort study. We included patients aged 65 years or older who were hospitalized for COVID-19 and dead o discharged between March 5 and 25, 2020. We used univariable and multivariable logistic regression methods to explore the risk factors associated with in-hospital death. RESULTS: 277 patients were included in this study. The bivariate analysis showed significant differences (p<0.05) between survivors and non survivors: age, increased dependence and comorbidity, history of ischemic heart disease, renal failure and non-hematological neoplasms, heart failure during admission, leukocytosis, elevated creatinine, PCR, GOT and troponin Ic values, lymphopenia, and decreased blood pH and SatO2. Multivariate logistic regression revealed that age ≥65 years (OR: 4.23 (95% CI: 1.43-12.52; p=0.009), lymphopenia <1000/µL (OR: 2.36 (95% CI: 1.07-5.20; p=0.033), creatinine>1.2mg/dL (OR: 3.08 (95% CI: 1.37-6.92; p=0.006), SatO2 <90% (OR: 2.29 (95% CI: 1.01-5.21; p=0.049) and troponin Ic>11ng/mL (OR: 2.32 (95% CI: 1.04-5.16; p=0.040) were independently associated with higher hospital mortality. CONCLUSIONS: Older age, lymphopenia, SatO2 <90%, elevated creatinine and troponin Ic values were independently associated with higher mortality in hospitalized patients with COVID-19, these factors could help clinicians to identify patients with poor prognosis.


Assuntos
COVID-19 , Fatores Etários , Idoso , Comorbidade , Mortalidade Hospitalar , Humanos , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2
15.
Rev. Méd. Clín. Condes ; 32(5): 535-542, sept.-oct. 2021. tab
Artigo em Espanhol | LILACS | ID: biblio-1526030

RESUMO

Los trastornos del sueño son frecuentes en la población y una causa importante de morbilidad. El objetivo de esta revisión es evaluar las alteraciones del sueño en periodos de emergencia y desastres. A lo largo de la historia, la esfera biopsicosocial y el sueño de las personas ha sido abrumada por múltiples eventos a gran escala, tales como desastres naturales, tragedias provocadas por el hombre, conflictos bélicos, crisis sociales y pandemias, cuya experiencia puede derivar en problemas de salud a corto, mediano y/o largo plazo. En los estudios analizados, se ha observado el impacto negativo de las emergencias y desastres en el sueño, por lo que ha cobrado gran relevancia la difusión y promoción de medidas que incentiven el buen dormir. Debido a la llegada del COVID-19 y a la situación de confinamiento por periodos prolongados en el hogar para prevenir su propagación, han surgido importantes consecuencias a nivel social. Ciertos factores ocupacionales y características de los desastres se asocian a mayor comorbilidad, un alto riesgo de experimentar agotamiento físico, trastornos psicológicos e insomnio en grupos altamente vulnerables, como lo son los profesionales de la salud, rescatistas y socorristas. El insomnio es el trastorno de sueño más frecuente en la población general y su empeoramiento en el contexto de pandemia por COVID-19 representa un nuevo problema en salud pública. Es por ello, que es indispensable promover campañas de prevención de salud física y mental orientados a la pesquisa precoz y manejo de patologías de la esfera psicosocial, dentro de las posibilidades socioeconómicas.


Sleep disorders are common in the population and are major cause of morbidity. The objective of this review is to assess sleep disturbances in times of emergency and disasters. Throughout history, the biopsychosocial field and sleep have been affected by multiple large-scale events, such as natural disasters, man-caused tragedies, armed conflicts, social crises and pandemics, the experience of which can lead to short, medium and/or long term health problems. In several studies, the negative impact of emergencies and disasters on sleep have been analyzed, emphasizing the importance of the diffusion and promotion of measures that encourage good sleep. The arrival of COVID-19 and consequent home confinement for prolonged periods caused important social consequences. Certain occupational factors and characteristics of disasters are associated with greater comorbidity: a high risk of experiencing physical exhaustion, psychological disorders and insomnia, especially in highly vulnerable groups, such as health professionals, rescuers and first aids-responders. Insomnia is the most frequent sleep disorder in the general population and its worsening in the context of the COVID-19 pandemic, represents a new public health problem. It is essential to promote physical and mental health prevention campaigns, aimed at early screening and management of pathologies in the psychosocial sphere, within socioeconomic possibilities.


Assuntos
Humanos , Transtornos do Sono-Vigília/diagnóstico , Transtornos do Sono-Vigília/psicologia , Transtornos do Sono-Vigília/prevenção & controle , Emergências em Desastres , Quarentena , Pessoal de Saúde/psicologia , Desastres , Pandemias , Socorristas/psicologia , COVID-19 , Distúrbios do Início e da Manutenção do Sono/classificação , Distúrbios do Início e da Manutenção do Sono/diagnóstico
16.
J Virol ; 95(21): e0043221, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34406866

RESUMO

Cassava mosaic disease (CMD), which is caused by single-stranded DNA begomoviruses, severely limits cassava production across Africa. A previous study showed that CMD symptom severity and viral DNA accumulation increase in cassava in the presence of a DNA sequence designated SEGS-2 (sequence enhancing geminivirus symptoms). We report here that when SEGS-2 is coinoculated with African cassava mosaic virus (ACMV) onto Arabidopsis thaliana, viral symptoms increase. Transgenic Arabidopsis with an integrated copy of SEGS-2 inoculated with ACMV also display increased symptom severity and viral DNA levels. Moreover, SEGS-2 enables Cabbage leaf curl virus (CaLCuV) to infect a geminivirus-resistant Arabidopsis thaliana accession. Although SEGS-2 is related to cassava genomic sequences, an earlier study showed that it occurs as episomes and is packaged into virions in CMD-infected cassava and viruliferous whiteflies. We identified SEGS-2 episomes in SEGS-2 transgenic Arabidopsis. The episomes occur as both double-stranded and single-stranded DNA, with the single-stranded form packaged into virions. In addition, SEGS-2 episomes replicate in tobacco protoplasts in the presence, but not the absence, of ACMV DNA-A. SEGS-2 episomes contain a SEGS-2 derived promoter and an open reading frame with the potential to encode a 75-amino acid protein. An ATG mutation at the beginning of the SEGS-2 coding region does not enhance ACMV infection in A. thaliana. Together, the results established that SEGS-2 is a new type of begomovirus satellite that enhances viral disease through the action of an SEGS-2-encoded protein that may also be encoded by the cassava genome. IMPORTANCE Cassava is an important root crop in the developing world and a food and income crop for more than 300 million African farmers. Cassava is rising in global importance and trade as the demands for biofuels and commercial starch increase. More than half of the world's cassava is produced in Africa, where it is primarily grown by smallholder farmers, many of whom are from the poorest villages. Although cassava can grow under high temperature, drought, and poor soil conditions, its production is severely limited by viral diseases. Cassava mosaic disease (CMD) is one of the most important viral diseases of cassava and can cause up to 100% yield losses. We provide evidence that SEGS-2, which was originally isolated from cassava crops displaying severe and atypical CMD symptoms in Tanzanian fields, is a novel begomovirus satellite that can compromise the development of durable CMD resistance.


Assuntos
Begomovirus/genética , Begomovirus/isolamento & purificação , Manihot/virologia , Doenças das Plantas/virologia , Vírus Satélites/genética , Vírus Satélites/isolamento & purificação , Begomovirus/classificação , Begomovirus/patogenicidade , DNA Viral/genética , Genoma Viral , Mutação , Filogenia , Recombinação Genética , Vírus Satélites/classificação , Vírus Satélites/patogenicidade , Nicotiana/virologia
17.
Childs Nerv Syst ; 37(8): 2619-2624, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33942143

RESUMO

BACKGROUND: The development of high levels of technical competence and excellent decision-making skills are key goals of all neurosurgical residency training programs. This acquisition of technical skills is becoming increasingly difficult due to many factors including less exposure to operative cases, demand for more time and cost-effective practices, and resident work hour restrictions. We describe a step-by-step method for how to build a low-cost and feasible model that allows residents to improve their neuroendoscopic skills. METHODS: The bell pepper-based model was developed as an endoscopic training model. Using continuous irrigation, several hands-on procedures were proposed under direct endoscopic visualization. Endoscope setup, endoscopic third ventriculostomy, septostomy, and tumor biopsy procedures were simulated and video recorded for further edition and analysis. RESULTS: The model can be setup in less than 15 min with minimal cost and infrastructure requirements. A single model allows simulation of all the exercises described above. The model allows exposure to the camera skills, instrument handling, and hand-eye coordination inherent to most neuroendoscopic procedures. CONCLUSION: Minimal infrastructure requirements, simplicity, and easily setup models provide a proper environment for regular training. The bell pepper-based model is inexpensive, widely available, and a feasible model for routine training. Neurosurgery residents may benefit from the use of this model to accelerate their learning curve and familiarize themselves with the neuroendoscopic core principles in a risk-free environment without time or resource constraints.


Assuntos
Internato e Residência , Neuroendoscopia , Neurocirurgia , Competência Clínica , Humanos , Neuroendoscópios , Neurocirurgia/educação , Procedimentos Neurocirúrgicos , Ventriculostomia
18.
Surg Oncol ; 36: 28-33, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33285433

RESUMO

PURPOSE: To assess the safety and effectiveness of magnetic seeds in preoperative localization and surgical dissection of metastatic axillary lymph nodes (LN+) in breast cancer patients with axillary involvement, after neoadjuvant chemotherapy (NAC). In addition, to assess the impact of targeted axillary dissection (TAD) in reducing the rate of false negatives (FN) in sentinel lymph node biopsy (SLNB). MATERIALS AND METHODS: A cross-sectional prospective cohort study was conducted from April 2017 to September 2019, including breast cancer patients with axillary lymph node involvement treated with NAC. Prior to NAC, the LN+ were marked by ultrasound-guided clip insertion. After NAC, a magnetic seed (Magseed®) was inserted in the clip-marked lymph node (MLN). During surgery, the MLN was located and removed with the aid of a magnetic detection probe (Sentimag®) and the sentinel lymph node was removed. Axillary lymph node dissection (ALND) was used to determine the rate of FN for SLNB alone and the combination of SLNB and MLN dissection, called TAD. RESULTS: The study included 29 patients (mean age, 55; range, 30-78 years). Selective preoperative localization and surgical dissection were successful for all 30 MLNs (100%). The MLN corresponded to the SLN in 50% of cases. After ALND, there were 21.4% (3/14) FN with SLNB alone and 5.9% (1/17) with TAD. CONCLUSIONS: Following NAC, selective surgical removal of MLN by preoperative localization using magnetic seeds is a safe and effective procedure with a success rate of 100%. Adding TAD reduces the rate of FN associated with SLNB alone.


Assuntos
Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante/métodos , Excisão de Linfonodo/métodos , Magnetismo , Mastectomia/métodos , Terapia Neoadjuvante/métodos , Biópsia de Linfonodo Sentinela/métodos , Adulto , Idoso , Axila , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Estudos Transversais , Feminino , Seguimentos , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Prognóstico , Estudos Prospectivos
19.
Brain Res ; 1747: 147031, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-32726601

RESUMO

The piriform cortex is involved in olfactory information processing, that is altered in Down Syndrome. Moreover, piriform cortex has a crucial involvement in epilepsy generation and is one of the first regions affected in Alzheimer's Disease, both maladies being prevalent among Down Syndrome individuals. In this work, we studied the alterations in neuronal morphology, synaptology and structural plasticity in the piriform cortex of the Ts65Dn mouse model, which is the most used model for the study of this syndrome and mimics some of their alterations. We have observed that Ts65Dn piriform cortex displays: a reduction in dendritic arborisation, a higher density of inhibitory synapses (GAD67), a lower density of excitatory synapses (vGLUT1) and a higher density of inhibitory postsynaptic puncta (gephyrin). Under electron microscopy the excitatory presynaptic and postsynaptic elements were larger in trisomic mice than in controls. Similar results were obtained using confocal microscopy. There were less immature neurons in piriform cortex layer II in addition to a reduction in the expression of PSA-NCAM in the neuropil that subsequently can reflect impairment in structural plasticity. These data support the idea of an impaired environment with altered ratio of inhibition and excitation that involves a reduction in plasticity and dendritic atrophy, providing a possible substrate for the olfactory processing impairment observed in DS individuals.


Assuntos
Síndrome de Down/metabolismo , Neurônios/metabolismo , Córtex Piriforme/metabolismo , Terminações Pré-Sinápticas/metabolismo , Animais , Síndrome de Down/genética , Síndrome de Down/patologia , Glutamato Descarboxilase/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Neurônios/ultraestrutura , Córtex Piriforme/ultraestrutura , Terminações Pré-Sinápticas/ultraestrutura , Proteína Vesicular 1 de Transporte de Glutamato/metabolismo
20.
Anesthesiology ; 132(4): 667-677, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32011334

RESUMO

BACKGROUND: Pneumoperitoneum for laparoscopic surgery is associated with a rise of driving pressure. The authors aimed to assess the effects of positive end-expiratory pressure (PEEP) on driving pressure at varying intraabdominal pressure levels. It was hypothesized that PEEP attenuates pneumoperitoneum-related rises in driving pressure. METHODS: Open-label, nonrandomized, crossover, clinical trial in patients undergoing laparoscopic cholecystectomy. "Targeted PEEP" (2 cm H2O above intraabdominal pressure) was compared with "standard PEEP" (5 cm H2O), with respect to the transpulmonary and respiratory system driving pressure at three predefined intraabdominal pressure levels, and each patient was ventilated with two levels of PEEP at the three intraabdominal pressure levels in the same sequence. The primary outcome was the difference in transpulmonary driving pressure between targeted PEEP and standard PEEP at the three levels of intraabdominal pressure. RESULTS: Thirty patients were included and analyzed. Targeted PEEP was 10, 14, and 17 cm H2O at intraabdominal pressure of 8, 12, and 15 mmHg, respectively. Compared to standard PEEP, targeted PEEP resulted in lower median transpulmonary driving pressure at intraabdominal pressure of 8 mmHg (7 [5 to 8] vs. 9 [7 to 11] cm H2O; P = 0.010; difference 2 [95% CI 0.5 to 4 cm H2O]); 12 mmHg (7 [4 to 9] vs.10 [7 to 12] cm H2O; P = 0.002; difference 3 [1 to 5] cm H2O); and 15 mmHg (7 [6 to 9] vs.12 [8 to 15] cm H2O; P < 0.001; difference 4 [2 to 6] cm H2O). The effects of targeted PEEP compared to standard PEEP on respiratory system driving pressure were comparable to the effects on transpulmonary driving pressure, though respiratory system driving pressure was higher than transpulmonary driving pressure at all intraabdominal pressure levels. CONCLUSIONS: Transpulmonary driving pressure rises with an increase in intraabdominal pressure, an effect that can be counterbalanced by targeted PEEP. Future studies have to elucidate which combination of PEEP and intraabdominal pressure is best in term of clinical outcomes.


Assuntos
Abdome/fisiopatologia , Laparoscopia/métodos , Monitorização Intraoperatória/métodos , Pneumoperitônio/fisiopatologia , Respiração com Pressão Positiva/métodos , Idoso , Estudos Cross-Over , Feminino , Humanos , Laparoscopia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Pneumoperitônio/diagnóstico , Pneumoperitônio/etiologia , Respiração com Pressão Positiva/efeitos adversos , Volume de Ventilação Pulmonar/fisiologia
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