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1.
Artigo em Inglês | MEDLINE | ID: mdl-38949236

RESUMO

BACKGROUND AND AIM: Sinonasal tumors are a rare and heterogeneous group of malignant tumors with different histopathological characteristics and clinical presentation. These tumors are usually treated through surgery. The aim of this study is to present our results of surgical therapy in patients with an advanced sinonasal tumor. METHODS: This retrospective study included patients with an advanced sinonasal tumor who were surgically treated. The surgical technique combined both a frontal transbasal approach together with an endoscopic endonasal approach. The parameters used for evaluation were the histological type of tumor, the radicality of resection (complete vs. incomplete), the frequency of recurrence, the surgical and postoperative complications, the type of subsequent oncological therapy and the overall survival. RESULTS: The group consisted of ten patients seven were men and three were women. Complete resection (defined as R0) was achieved in 8 (80%) of the cases, subcomplete resection was achieved in 2 (20%) of the cases. The overall survival period was 28.7 months (95% confidence interval 15.9-41.6). CONCLUSION: The combination of the frontal transbasal approach with the endoscopic endonasal approach is a suitable surgical strategy that enables easier achievement of complete tumor resection, reconstruction of the anterior skull base and reduces the need for extensive surgical approaches.

2.
Plant Physiol ; 195(1): 698-712, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38236304

RESUMO

Many insects have evolved the ability to manipulate plant growth to generate extraordinary structures called galls, in which insect larva can develop while being sheltered and feeding on the plant. In particular, cynipid (Hymenoptera: Cynipidae) wasps have evolved to form morphologically complex galls and generate an astonishing array of gall shapes, colors, and sizes. However, the biochemical basis underlying these remarkable cellular and developmental transformations remains poorly understood. A key determinant in plant cellular development is cell wall deposition that dictates the physical form and physiological function of newly developing cells, tissues, and organs. However, it is unclear to what degree cell walls are restructured to initiate and support the formation of new gall tissue. Here, we characterize the molecular alterations underlying gall development using a combination of metabolomic, histological, and biochemical techniques to elucidate how valley oak (Quercus lobata) leaf cells are reprogrammed to form galls. Strikingly, gall development involves an exceptionally coordinated spatial deposition of lignin and xylan to form de novo gall vasculature. Our results highlight how cynipid wasps can radically change the metabolite profile and restructure the cell wall to enable the formation of galls, providing insights into the mechanism of gall induction and the extent to which plants can be entirely reprogrammed to form unique structures and organs.


Assuntos
Parede Celular , Interações Hospedeiro-Parasita , Tumores de Planta , Vespas , Animais , Parede Celular/metabolismo , Vespas/fisiologia , Tumores de Planta/parasitologia , Quercus/metabolismo , Quercus/parasitologia , Folhas de Planta/metabolismo , Folhas de Planta/parasitologia , Lignina/metabolismo
3.
Artigo em Inglês | MEDLINE | ID: mdl-37737300

RESUMO

INTRODUCTION: Functioning pituitary adenomas lead to substantial morbidity and increased mortality associated with typical endocrine syndromes. Surgical therapy is an integral part of the management of these tumours. The aim of this study was to evaluate the results of surgical transnasal procedures in patients with functioning pituitary adenomas who underwent the surgery at the Department of Neurosurgery, University Hospital Olomouc. METHODS: Patients with functioning pituitary adenoma (ACTH, GH, PRL) were indicated for surgery. All patients underwent preoperative and postoperative endocrinological examination and laboratory tests to assess excessive or deficient hormonal production and imaging examination. RESULTS: The cohort consisted of 58 patients, 33 of whom were women and 25 men. The age range was 12-77 years (mean age 47.6 years). Microadenoma was diagnosed in 58.6% of patients and macroadenoma in 41.4% of patients. The most common hypersecretory syndrome was excessive production of growth hormone (56.9%), followed by excessive production of adrenocorticotropic hormone (24.1%) and prolactin (12.1%). In the group with excessive production of ACTH, complete remission was achieved after the first surgery in 78.6% of cases (72.8% for microadenomas (8) and 100% (3) cases in macroadenomas); in the group with excessive GH production in 51.4% (63.2% (7) in microadenomas and 46.2% (12) cases in macroadenomas). In the group with excessive production of PRL, it was 57.1% (100% (2) in microadenomas and 40% (2) cases in macroadenomas). CONCLUSION: Surgical therapy in the presented cohort led to the normalisation of hormonal excessive production in 58.6% of cases. A combination of drug therapy and radiotherapeutic methods was necessary in the remaining cases to achieve hormonal remission.

4.
Sci Rep ; 12(1): 16691, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-36202874

RESUMO

In this work, the electrochemical properties of the leached sludge, magnetite and zinc ferrite were studied. Acetic acid was used as a leaching reagent because, in recent years, there has been a surge of interest in using zinc-containing materials as photocatalysts, with acetic acid finding application in their preparation. Various methodological approaches were used, but the best results were achieved with a combination of 1-3 h leaching in 0.01 M acetic acid with a solid/liquid ratio of 500. In this arrangement, zincite was almost completely removed from the sludge, while zinc ferrite and magnetite remained in the solid residue. Ex situ analyses of the main leaching products were performed by X-ray diffraction, infrared spectroscopy, and thermogravimetry. The electrochemical behaviour of solid residue and model systems, that are micromagnetite and zinc ferrite, was studied in alkaline media by means of modified carbon paste electrodes, cyclic voltammetry, and chronocoulometry, with a suitable potential window ranging from 0 to 1.5 V. In summary, a linear dependence of the anodic and cathodic peak height on the square root of the scan rate was found. The position of the anodic and cathodic peaks shifted slightly with scan rate, only at low rates, up to 25 mV/s, the individual peaks coincided. The electrochemical response suggested a quasireversible process.


Assuntos
Esgotos , Aço , Carbono/química , Técnicas Eletroquímicas , Eletrodos , Compostos Férricos , Óxido Ferroso-Férrico , Zinco/química
5.
Materials (Basel) ; 15(4)2022 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-35208132

RESUMO

This work aims to assess the effect of an oxygen content graded in minimal quantities, on the order of hundreds of ppms, on the determination of surface tension of low-alloy FeCOCr and FeCONi steels in contact with a corundum substrate. Oxygen, as a surface-active element, was segregated at the surface where it interacted with the major components of the alloys, leading to a reduction in surface tension. The sessile drop method was used for wetting tests in the temperature range from steel liquidus temperatures to 1600 °C under nonoxidizing conditions. The effect of oxygen on surface tension and wetting angles was verified by statistical analysis using the Kruskal-Wallis test, which supported the results stating that the values of these quantities decreased with increasing oxygen content. Furthermore, liquidus temperatures, which are of practical importance, were determined by the optical and DTA methods and then compared with theoretically calculated temperature values. It turned out that the increased chromium content causes difficulties in determining surface tension up to 1550 °C due to the formation of a thin Cr2O3 layer. In addition, SEM and XRD analyses accompanied by calculations in the FactSage oxide database were performed to better understand the wetting mechanism.

6.
Artigo em Inglês | MEDLINE | ID: mdl-34446940

RESUMO

BACKGROUND: Transsphenoid meningoencephalocele is a congenital anomaly formed by herniation of an ependyma delimited sac through a bony defect into the sphenoid sinus. The sac contains cerebrospinal fluid and neurovascular structures. The prevalence of transsphenoid meningoencephalocele in the adult population is rare. It usually manifests as nasal liquorrhoea. METHODS AND RESULTS: This case report presents an adult male who underwent surgery due to suspected pituitary macroadenoma. The surgery was performed endoscopically via the transnasal approach with a surprising finding of true transsphenoid meningoencephalocele. Ectopic solid tissue was found in the sphenoid sinus in which pituitary adenoma was histologically confirmed. CONCLUSION: This paper presents a previously unpublished combination of true transsphenoid meningoencephalocele and pituitary adenoma in an adult individual.


Assuntos
Adenoma , Meningocele , Neoplasias Hipofisárias , Adenoma/complicações , Adenoma/patologia , Adenoma/cirurgia , Adulto , Encefalocele/etiologia , Encefalocele/patologia , Encefalocele/cirurgia , Endoscopia/métodos , Humanos , Masculino , Meningocele/diagnóstico por imagem , Meningocele/patologia , Meningocele/cirurgia , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/patologia , Neoplasias Hipofisárias/cirurgia , Seio Esfenoidal/patologia , Seio Esfenoidal/cirurgia
7.
Sci Rep ; 11(1): 23351, 2021 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-34857834

RESUMO

Endoscopic endonasal approach uses the nasal cavity and paranasal sinuses to access the cranial base and may be a source of post-surgical morbidity in many patients with a sellar tumour. The objective of the presented study was to evaluate sinonasal quality of life and assess the effect of chosen reconstruction of the cranial base on the final condition. 65 patients, 33 male and 32 female who underwent an endoscopic endonasal surgery due to sellar expansion, were included into this prospective study. Sinonasal quality of life was evaluated using the Sinonasal Outcome Test-22 (SNOT-22) questionnaire before the surgery and six months after the surgery. Sinonasal quality of life was evaluated for the total cohort of patients and for patients after reconstruction (fascia lata, muscle) and without reconstruction. The minimum follow-up period was one year. There was no significant difference between the score (SNOT-22) before the surgery (average 14.4 points) and after the surgery (average 17.5 points), p = 0.067 in the whole cohort. Statistically significant differences were found in the following items-the need to blow nose, nasal congestion, loss of smell and taste, and thick discharge from the nose. The comparison of subgroups with and without the reconstruction yielded statistically significant differences in favour of patients with reconstruction in the following items-lack of high-quality sleep and feeling exhaustion. The endoscopic endonasal approach in patients with a sellar tumour is a gentle method with minimal effects on sinonasal quality of life over a period longer than six months. The most common complaints are the need to blow nose, nasal congestion, loss of smell and taste, and thick discharge from the nose. Cranial base reconstruction using the muscle and fascia lata seems to be a potential factor positively influencing sinonasal quality of life.


Assuntos
Endoscopia/efeitos adversos , Cavidade Nasal/cirurgia , Doenças Nasais/patologia , Seios Paranasais/cirurgia , Neoplasias Hipofisárias/cirurgia , Qualidade de Vida , Sela Túrcica/cirurgia , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Cavidade Nasal/patologia , Doenças Nasais/etiologia , Seios Paranasais/patologia , Neoplasias Hipofisárias/patologia , Prognóstico , Estudos Prospectivos , Sela Túrcica/patologia , Adulto Jovem
8.
BMC Surg ; 21(1): 58, 2021 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-33485359

RESUMO

BACKGROUND: Endoscopic endonasal transsphenoidal approaches are broadly used nowadays for a vast spectrum of pathologies sited in the anterior and middle cranial fossa. The usage of neuronavigation systems (neuronavigation) in these surgeries is crucial for improving orientations deeply inside the skull and increasing patient safety. METHODS: The aim of this study was to assess the use of optical neuronavigation, together with an intraoperative O-arm O2 imaging system, in a group of patients with hypophyseal adenoma that underwent a transnasal transsphenoidal surgery, and correlate the accuracy and its deviation during the navigational process against the use of conventional neuronavigation that uses preoperative MRI and CT scans. The overall group consisted of six patients, between 39 and 78 years old, with a diagnosis of hypophyseal adenoma. Patients were treated with an endoscopic transsphenoidal technique and all of them underwent preoperative MRI and CT scans of the brain. These images were used in the neuronavigation system StealthStation S7® during the surgery, where we defined two bony anatomical landmarks, such as a vomer or the origin of an intrasphenoidal septum, in each operated patient. The tip of the navigational instrument, under endoscopic control, pointed to these landmarks and the distance between the tip and the bony structure was measured on the neuronavigation system. Afterwards, intraoperative 3D x-ray imaging was performed via the mobile system O-arm O2® system with automatic transfer into the navigational system. Under endoscopic guidance, we localized the identical bony anatomical landmarks used in the previous measurement and re-measured the distance between the tip and bony landmark in images acquired by the O-arm. The results of both measurements were statistically compared. RESULTS: The mean error of accuracy during conventional neuronavigation with usage of preoperative CT and MRI scans was 2.65 mm. During the neuronavigation, with utilization of intraoperative 3D O-arm images, the mean error of accuracy 0 mm. These mean errors of accuracy (both measurement methods were compared by nonparametric Wilcoxon test) had a statistically significant difference (p = 0.043). CONCLUSIONS: Based on this preliminary clinical study, we conclude that the O-arm is capable of providing intraoperative x-ray 3D images in sufficient spatial resolution in a clinically feasible acquisition. The mean error of accuracy during intraoperative navigation, based on 3D O-arm scans at the skull base, is significantly lower compared to the usage of navigation using conventional presurgical CT and MRI images. This suggests the suitability of this method for utilization during endoscopic endonasal skull base approaches.


Assuntos
Adenoma , Hipófise , Neoplasias Hipofisárias , Base do Crânio , Cirurgia Assistida por Computador , Cirurgia Endoscópica Transanal , Adenoma/diagnóstico por imagem , Adenoma/cirurgia , Adulto , Idoso , Feminino , Humanos , Imageamento Tridimensional , Período Intraoperatório , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuronavegação/métodos , Projetos Piloto , Hipófise/diagnóstico por imagem , Hipófise/cirurgia , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/cirurgia , Estudos Prospectivos , Base do Crânio/diagnóstico por imagem , Base do Crânio/cirurgia , Cirurgia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X , Cirurgia Endoscópica Transanal/métodos
9.
Nat Plants ; 3: 16208, 2017 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-28085153

RESUMO

Plants sequester intermediates of metabolic pathways into different cellular compartments, but the mechanisms by which these molecules are transported remain poorly understood. Monoterpene indole alkaloids, a class of specialized metabolites that includes the anticancer agent vincristine, antimalarial quinine and neurotoxin strychnine, are synthesized in several different cellular locations. However, the transporters that control the movement of these biosynthetic intermediates within cellular compartments have not been discovered. Here we present the discovery of a tonoplast localized nitrate/peptide family (NPF) transporter from Catharanthus roseus, CrNPF2.9, that exports strictosidine, the central intermediate of this pathway, into the cytosol from the vacuole. This discovery highlights the role that intracellular localization plays in specialized metabolism, and sets the stage for understanding and controlling the central branch point of this pharmacologically important group of compounds.


Assuntos
Proteínas de Transporte de Ânions/genética , Catharanthus/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Simportadores/genética , Alcaloides de Vinca/metabolismo , Proteínas de Transporte de Ânions/metabolismo , Transporte Biológico , Catharanthus/metabolismo , Monoterpenos/metabolismo , Transportadores de Nitrato , Proteínas de Plantas/metabolismo , Simportadores/metabolismo , Vacúolos/metabolismo
10.
Artigo em Inglês | MEDLINE | ID: mdl-23945847

RESUMO

AIM: The aim of this study was to compare resection and biopsy of glioblastoma (GBM) in eloquent brain areas (EBA). METHODS: This was a prospective evaluation of 38 patients with GBM in EBA. 22 were treated by surgical resection and 16 by biopsy. Preoperative KPS, neurological status and size of lesion on MRI were assessed. One week and three months postoperatively KPS, neurological status and Performance Status (PS) WHO were evaluated. Extent of resection (EOR) and overall survival (OS) were described. Overall mean age of the patients was 64.3 years, the mean lesion size in the resection group was 47.7 mm and in the biopsy group 51.0 mm. RESULTS: Worsening or development of permanent neurological deficits 3 months after surgery were significantly lower in the resection group (23%), than the biopsy group (94%). In the resection group the median pre and postoperative KPS three months after surgery was 80.0. In the biopsy group the median pre and postoperative KPS was 68.1 one week after the procedure. In the resection group, 3 months after surgery, the median PS was 1, in the biopsy group one week after surgery the median PS was 2. The difference was statistically insignificant. The mean OS after resection was 12.2 months, and after biopsy 3.5 months. The difference was highly statistically significant. The mean EOR was 90%. CONCLUSION: This is the first prospective study, to our knowledge, that compares the results of resection and biopsy of primary GBM in EBA. For patients in good clinical condition with tumors in or near EBA, recommended is as radical resection of GBM as possible.


Assuntos
Biópsia/métodos , Neoplasias Encefálicas/cirurgia , Encéfalo/patologia , Glioblastoma/cirurgia , Procedimentos Neurocirúrgicos/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/cirurgia , Neoplasias Encefálicas/diagnóstico , Feminino , Glioblastoma/diagnóstico , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos
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