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1.
BMC Immunol ; 25(1): 9, 2024 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-38273260

RESUMEN

BACKGROUND: Intra-ductal cancer (IDC) is the most common type of breast cancer, with intra-lobular cancer (ILC) coming in second. Surgery is the primary treatment for early stage breast cancer. There are now irrefutable data demonstrating that the immune context of breast tumors can influence growth and metastasis. Adjuvant chemotherapy may be administered in patients who are at a high risk of recurrence. Our goal was to identify the processes underlying both types of early local recurrences. METHODS: This was a case-control observational study. Within 2 years of receiving adjuvant taxan and anthracycline-based chemotherapy, as well as modified radical mastectomy (MRM), early stage IDC and ILC recurred. Vimentin, α-smooth muscle actin (SMA), platelet-derived growth factor (PDGF), matrix metalloproteinase (MMP1), and clustered differentiation (CD95) were investigated. RESULTS: Of the samples in the ductal type group, 25 showed local recurrence, and 25 did not. Six individuals in the lobular-type group did not experience recurrence, whereas seven did. Vimentin (p = 0.000 and 0.021), PDGF (p = 0.000 and 0.002), and CD95 (p = 0.000 and 0.045) expressions were significantly different in ductal and lobular carcinoma types, respectively. Measurement of ductal type was the sole significant difference found in MMP1 (p = 0.000) and α-SMA (p = 0.000). α-SMA and CD95 were two variables that helped the recurrence mechanism in the ductal type according to the pathway analysis. In contrast, the CD95 route is a recurrent mechanism for the lobular form. CONCLUSIONS: While the immune system plays a larger role in ILC, the tumor microenvironment and immune system both influence the recurrence of IDC. According to this study, improving the immune system may be a viable cancer treatment option.


Asunto(s)
Neoplasias de la Mama , Carcinoma Ductal de Mama , Carcinoma Lobular , Humanos , Femenino , Neoplasias de la Mama/cirugía , Mastectomía , Vimentina/uso terapéutico , Carcinoma Ductal de Mama/patología , Carcinoma Ductal de Mama/secundario , Carcinoma Ductal de Mama/cirugía , Microambiente Tumoral , Metaloproteinasa 1 de la Matriz/uso terapéutico , Carcinoma Lobular/patología , Carcinoma Lobular/secundario , Carcinoma Lobular/cirugía
2.
J Neurol Neurosurg Psychiatry ; 95(3): 256-263, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-37673641

RESUMEN

BACKGROUND: Moyamoya is a chronic occlusive cerebrovascular disease of unknown etiology causing neovascularization of the lenticulostriate collaterals at the base of the brain. Although revascularization surgery is the most effective treatment for moyamoya, there is still no consensus on the best surgical treatment modality as different studies provide different outcomes. OBJECTIVE: In this large case series, we compare the outcomes of direct (DR) and indirect revascularisation (IR) and compare our results to the literature in order to reflect on the best revascularization modality for moyamoya. METHODS: We conducted a multicenter retrospective study in accordance with the Strengthening the Reporting of Observational studies in Epidemiology guidelines of moyamoya affected hemispheres treated with DR and IR surgeries across 13 academic institutions predominantly in North America. All patients who underwent surgical revascularization of their moyamoya-affected hemispheres were included in the study. The primary outcome of the study was the rate of symptomatic strokes. RESULTS: The rates of symptomatic strokes across 515 disease-affected hemispheres were comparable between the two cohorts (11.6% in the DR cohort vs 9.6% in the IR cohort, OR 1.238 (95% CI 0.651 to 2.354), p=0.514). The rate of total perioperative strokes was slightly higher in the DR cohort (6.1% for DR vs 2.0% for IR, OR 3.129 (95% CI 0.991 to 9.875), p=0.052). The rate of total follow-up strokes was slightly higher in the IR cohort (8.1% vs 6.6%, OR 0.799 (95% CI 0.374 to 1.709) p=0.563). CONCLUSION: Since both modalities showed comparable rates of overall total strokes, both modalities of revascularization can be performed depending on the patient's risk assessment.


Asunto(s)
Revascularización Cerebral , Enfermedad de Moyamoya , Accidente Cerebrovascular , Humanos , Estudios Retrospectivos , Revascularización Cerebral/efectos adversos , Revascularización Cerebral/métodos , Resultado del Tratamiento , Accidente Cerebrovascular/etiología , Enfermedad de Moyamoya/cirugía
3.
Neuropathology ; 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38639066

RESUMEN

In the evolving landscape of ependymoma classification, which integrates histological, molecular, and anatomical context, we detail a rare case divergent from the usual histopathological spectrum. We present the case of a 37-year-old man with symptomatic spinal cord compression at the L3-L4 level. Neuroradiological evaluation revealed an intradural, encapsulated mass. Histologically, the tumor displayed atypical features: bizarre pleomorphic giant cells, intranuclear inclusions, mitotic activity, and a profusion of eosinophilic cytoplasm with hyalinized vessels, deviating from the characteristic perivascular pseudorosettes or myxopapillary patterns. Immunohistochemical staining bolstered this divergence, marking the tumor cells positive for glial fibrillary acidic protein and epithelial membrane antigen with a characteristic ring-like pattern, and CD99 but negative for Olig-2. These markers, alongside methylation profiling, facilitated its classification as a myxopapillary ependymoma (MPE), despite the atypical histologic features. This profile underscores the necessity of a multifaceted diagnostic process, especially when histological presentation is uncommon, confirming the critical role of immunohistochemistry and molecular diagnostics in classifying morphologically ambiguous ependymomas and exemplifying the histological diversity within MPEs.

4.
Eur Spine J ; 33(3): 985-1000, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38110776

RESUMEN

BACKGROUND: Awake surgery, under spinal anesthesia (SA), is an alternative to surgery under general anesthesia (GA), in neurological and spine surgery. In the literature, there seem to be some evidence supporting benefits associated with the use of this anesthetic modality, as compared to GA. Currently, there is a notable lack of updated and comprehensive review addressing the complications associated with both awake SA and GA in spine surgery. We hence aimed to perform a systematic review of the literature and meta-analysis on the topic. METHODS: A systematic search was conducted to identify studies that assessed SA in spine surgery from database inception to April 14, 2023, in PubMed, Medline, Embase, and Cochrane databases. Outcomes of interest included estimated blood loss, length of hospital stay, operative time, and overall complications. Meta-analysis was conducted using random effects models. RESULTS: In total, 38 studies that assessed 7820 patients were included. The majority of the operations that were treated with SA were single-level lumbar cases. Awake patients had significantly shorter lengths of hospital stay (Mean difference (MD): - 0.40 days; 95% CI - 0.64 to - 0.17) and operative time (MD: - 19.17 min; 95% CI - 29.68 to - 8.65) compared to patients under GA. The overall complication rate was significantly higher in patients under GA than SA (RR, 0.59 [95% CI 0.47-0.74]). Patients under GA had significantly higher rates of postoperative nausea/vomiting RR, 0.60 [95% CI 0.39-0.90]) and urinary retention (RR, 0.61 [95% CI 0.37-0.99]). CONCLUSIONS: Patients undergoing awake spine surgery under SA had significantly shorter operations and hospital stays, and fewer rates of postoperative nausea and urinary retention as compared to GA. In summary, awake spine surgery offers a valid alternative to GA and added benefits in terms of postsurgical complications, while being associated with relatively low morbidity.


Asunto(s)
Anestesia Raquidea , Neoplasias Encefálicas , Retención Urinaria , Humanos , Náusea y Vómito Posoperatorios , Vigilia , Anestesia General/efectos adversos
5.
BMC Surg ; 23(1): 230, 2023 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-37568135

RESUMEN

INTRODUCTION: The spleen is a responsible significant part of the immune system; after Splenectomy following trauma, the immune system changes; splenic autotransplantation can preserve the immune system after trauma and Splenectomy. BACKGROUND: Patients can be protected from immune dysfunction by autotransplanting splenic tissues after splenectomy following trauma because their immune systems and spleens are changed. Patients can gain their immune function after splenic autotransplantation. METHODS: Patient classification methods are into three categories, Group A, 6 cases with auto-translation; Group B, 6 cases without transplantation; Group C, seven regular people serving as the control. AIM OF WORK: The aim of the work is not to compare outcome methods or compare types of autotransplantation; This work aims to document postoperative radiological, immunological, clinical, and hematological investigations. We concentrated on the results of investigations more than the types of operation or approach or types of autotransplantation. RESULTS: We showed that, after comparing each group with normal individuals subjects, patients who did not undergo autotransplantation had significantly higher platelet counts, a more significant percentage of micronucleated reticulocytes, increased levels of naive B lymphocytes, changes in class-switched memory and class-unswitched memory B cells, and higher levels of PD1 on CD8 + T lymphocytes. Nevertheless, neither splenic autotransplant patients nor the average general population showed any appreciable variations in any of the parameters. CONCLUSIONS: Spleen's activities with adequate hemocatheter activity and recovery of the immunological deficit after splenic autotransplantation.


Asunto(s)
Bazo , Esplenectomía , Humanos , Bazo/cirugía , Esplenectomía/métodos , Trasplante Autólogo
6.
Br J Neurosurg ; 37(5): 1271-1272, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33241950

RESUMEN

We present a case of extradural hematoma resulting from a relatively minor closed injury over the vertex where a plasma cell tumour had invaded the superior sagittal sinus. The patient underwent an emergency craniotomy and evacuation of the hematoma. Hemostasis and prevention of recollection of the hematoma were hampered by the erosion of the sagittal sinus making its direct repair impossible. This was achieved by hitching up the dura lateral to the sinus to become its lateral wall reinforced by hemostatic agents. The patient made a full recovery. Malignant tumours invading the dural venous sinuses and eroding the skull can cause life-threatening intracranial bleeding after relatively minor trauma.


Asunto(s)
Hematoma Epidural Craneal , Fracturas Craneales , Neoplasias Craneales , Humanos , Senos Craneales/cirugía , Craneotomía/métodos , Hematoma Epidural Craneal/diagnóstico por imagen , Hematoma Epidural Craneal/etiología , Hematoma Epidural Craneal/cirugía , Cráneo/cirugía , Fracturas Craneales/cirugía , Neoplasias Craneales/diagnóstico por imagen , Neoplasias Craneales/cirugía , Masculino , Adulto
7.
Neurosurg Rev ; 44(6): 2991-2999, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33543414

RESUMEN

Aneurysms arising from the distal carotid, proximal A1, and proximal M1 that project posteriorly and superiorly toward the anterior perforated substance (APS) are rare. Their open surgical treatment is particularly difficult due to poorly visualized origin of the aneurysm and the abundance of surrounding perforators. We sought to analyze the anatomical and clinical characteristics of APS aneurysms and discuss surgical nuances that can optimize visualization, complete neck clip obliteration, and preservation of adjacent perforators. Thirty-two patients with 36 APS aneurysms were surgically treated between November 2000 and September 2017. Patients were prospectively enrolled in a cerebral aneurysm database and their clinical, imaging, and surgical records were retrospectively reviewed. Twenty-seven aneurysms originated from the distal ICA, 7 from the proximal A1, and 2 from the proximal M1; 15 patients presented with subarachnoid hemorrhage. Careful intraoperative dissection revealed 4 aneurysms originating at the takeoff of a perforator; another 25 had at least 1 adherent perforator. All aneurysms were clipped except for one that was trapped. Postoperatively, 3 patients had radiographic infarctions in perforator territory with only 1 developing delayed clinical hemiparesis. Good outcome (modified Rankin Scale, 0-2) was achieved in 28 patients (88%). APS aneurysms present a challenging subset of aneurysms due to their complex anatomical relationship with surrounding perforators. These should be identified on preoperative imaging based on location and projection. Successful microsurgical clipping relies on optimization of the surgical view, meticulous clip reconstruction, preservation of all perforators, and electrophysiological monitoring to minimize ischemic complication.


Asunto(s)
Aneurisma Intracraneal , Hemorragia Subaracnoidea , Humanos , Aneurisma Intracraneal/cirugía , Estudios Retrospectivos , Hemorragia Subaracnoidea/cirugía , Instrumentos Quirúrgicos , Resultado del Tratamiento
8.
Sensors (Basel) ; 21(21)2021 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-34770720

RESUMEN

In this work, a new prototype of the eight-element MIMO antenna system for 5G communications, internet of things, and networks has been proposed. This system is based on an H-shaped monopole antenna system that offers 200 MHz bandwidth ranges between 3.4-3.6 GHz, and the isolation between any two elements is well below -12 dB without using any decoupling structure. The proposed system is designed on a commercially available 0.8 mm-thick FR4 substrate. One side of the chassis is used to place the radiating elements, while the copper from the other side is being removed to avoid short-circuiting with other components and devices. This also enables space for other systems, sub-systems, and components. A prototype is fabricated and excellent agreement is observed between the experimental and the computed results. It was found that ECC is 0.2 for any two radiating elements which is consistent with the desirable standards, and channel capacity is 38 bps/Hz which is 2.9 times higher than 4 × 4 MIMO configuration. In addition, single hand mode and dual hand mode analysis are conducted to understand the operation of the system under such operations and to identify losses and/or changes in the key performance parameters. Based on the results, the proposed antenna system will find its applications in modern 5G handheld devices and internet of things with healthcare and high rate delivery. Besides that, its design simplicity will make it applicable for mass production to be used in industrial demands.


Asunto(s)
Atención a la Salud , Tecnología Inalámbrica , Diseño de Equipo
9.
Molecules ; 19(5): 5940-51, 2014 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-24818574

RESUMEN

A phytochemical investigation of the least polar organic extracts of Arnebia hispidissima (Lehm.) DC. roots has led to the isolation of two unique polycyclic geranylhydroquinone-derived metabolites, arnebacene (1) and arnebidin (2), along with some known phenolic metabolites viz., arnebin-7 (3) and vanillic acid (4). The chemical identification of the new isolated compounds, including their relative stereochemistry, was achieved via spectroscopic analyses, including 2D NMR, and spectral comparison with related compounds. A biosynthetic pathway is proposed for the new compounds on the basis of their structure-relationship with previously isolated metabolites.


Asunto(s)
Redes y Vías Metabólicas , Extractos Vegetales/química , Compuestos Policíclicos/química , Terpenos/química , Boraginaceae , Estructura Molecular , Raíces de Plantas/química , Compuestos Policíclicos/aislamiento & purificación , Compuestos Policíclicos/metabolismo , Terpenos/aislamiento & purificación , Terpenos/metabolismo
10.
Neurosurgery ; 94(2): 413-422, 2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-37856210

RESUMEN

BACKGROUND AND OBJECTIVES: Nongeneral anesthesia (non-GA) spine surgery is growing in popularity and has facilitated earlier postoperative recovery, reduced cost, and fewer complications compared with spine surgery under general anesthesia (GA). Changes in reimbursement policies have been demonstrated to correlate with clinical practice; however, they have yet to be studied for GA vs non-GA spine procedures. We aimed to investigate trends in physician reimbursement for GA vs non-GA spine surgery in the United States. METHODS: We queried the ACS-NSQIP for GA and non-GA (regional, epidural, spinal, and anesthesia care/intravenous sedation) spine surgeries during 2011-2020. Work relative value units per operative hour (wRVUs/h) were retrieved for decompression or stabilization of the cervical, thoracic, and lumbar spine. Propensity score matching (1:1) was performed using all baseline variables. RESULTS: We included 474 706 patients who underwent spine decompression or stabilization procedures. GA was used in 472 248 operations, whereas 2458 operations were non-GA. The proportion of non-GA spine operations significantly increased during the study period. Operative times ( P < .001) and length of stays ( P < .001) were shorter in non-GA when compared with GA procedures. Non-GA lumbar procedures had significantly higher wRVUs/h when compared with the same procedures performed under GA (decompression; P < .001 and stabilization; P = .039). However, the same could not be said about cervicothoracic procedures. Lumbar decompression surgeries using non-GA witnessed significant yearly increase in wRVUs/h ( P < .01) contrary to GA ( P = .72). Physician reimbursement remained stable for procedures of the cervical or thoracic spine regardless of the anesthesia. CONCLUSION: Non-GA lumbar decompressions and stabilizations are associated with higher and increasing reimbursement trends (wRVUs/h) compared with those under GA. Reimbursement for cervical and thoracic surgeries was equal regardless of the type of anesthesia and being relatively stable during the study period. The adoption of a non-GA technique relative to the GA increased significantly during the study period.


Asunto(s)
Vértebras Lumbares , Procedimientos Neuroquirúrgicos , Humanos , Estados Unidos , Vértebras Lumbares/cirugía , Anestesia General/métodos , Descompresión Quirúrgica , Periodo Posoperatorio , Estudios Retrospectivos
11.
Neural Regen Res ; 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38845224

RESUMEN

ABSTRACT: Spinal cord injury remains a major cause of disability in young adults, and beyond acute decompression and rehabilitation, there are no pharmacological treatments to limit the progression of injury and optimize recovery in this population. Following the thorough investigation of the complement system in triggering and propagating cerebral neuroinflammation, a similar role for complement in spinal neuroinflammation is a focus of ongoing research. In this work, we survey the current literature investigating the role of complement in spinal cord injury including the sources of complement proteins, triggers of complement activation, and role of effector functions in the pathology. We study relevant data demonstrating the different triggers of complement activation after spinal cord injury including direct binding to cellular debris, and or activation via antibody binding to damage-associated molecular patterns. Several effector functions of complement have been implicated in spinal cord injury, and we critically evaluate recent studies on the dual role of complement anaphylatoxins in spinal cord injury while emphasizing the lack of pathophysiological understanding of the role of opsonins in spinal cord injury. Following this pathophysiological review, we systematically review the different translational approaches used in preclinical models of spinal cord injury and discuss the challenges for future translation into human subjects. This review emphasizes the need for future studies to dissect the roles of different complement pathways in the pathology of spinal cord injury, to evaluate the phases of involvement of opsonins and anaphylatoxins, and to study the role of complement in white matter degeneration and regeneration using translational strategies to supplement genetic models.

12.
J Neurointerv Surg ; 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38238008

RESUMEN

BACKGROUND: Endovascular thrombectomy (EVT) remains the standard of care for acute large vessel occlusion (LVO) stroke. However, the safety and efficacy of repeat thrombectomy (rEVT) in recurrent LVO remains unclear. This study uses a large real-world patient cohort to study technical and clinical outcomes after rEVT. METHODS: This is a retrospective cohort study including patients who underwent thrombectomy between January 2013 and December 2022. Data were included from 21 comprehensive stroke centers globally through the Stroke Thrombectomy and Aneurysm Registry (STAR). Patients undergoing single EVT or rEVT within 30 days of LVO stroke were included in the study. Propensity score matching was used to compare patients undergoing single EVT versus rEVT. RESULTS: Out of a total of 7387 patients who underwent thrombectomy for LVO stroke, 90 (1.2%) patients underwent rEVT for the same vascular territory within 30 days. The median (IQR) time to re-occlusion was 2 (1-7) days. Compared with a matched cohort of patients undergoing a single EVT procedure, patients undergoing rEVT had a comparable rate of good functional outcome and mortality rate, but a higher rate of symptomatic intracranial hemorrhage (sICH). There was a significant reduction in the National Institutes of Health Stroke Scale (NIHSS) score of patients who underwent rEVT at discharge compared with baseline (-4.8±11.4; P=0.006). The rate of successful recanalization was similar in the single thrombectomy and rEVT groups (78% vs 80%, P=0.171) and between index and rEVT performed on the same patient (79% vs 80%; P=0.593). CONCLUSION: Short-interval rEVT is associated with an improvement in the NIHSS score following large vessel re-occlusion. Compared with single thrombectomy, there was a higher rate of sICH with rEVT, but without a significant impact on rates of functional independence or mortality.

13.
J Nat Prod ; 76(6): 1099-104, 2013 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-23713692

RESUMEN

The endophytic fungus Penicillium citrinum was isolated from a fresh stem of the Moroccan plant Ceratonia siliqua. Extracts of P. citrinum grown on rice and white bean media yielded five new compounds, namely, citriquinochroman (1), tanzawaic acids G and H (2 and 3), 6-methylcurvulinic acid (4), 8-methoxy-3,5-dimethylisoquinolin-6-ol (5), and one new natural product, 1,2,3,11b-tetrahydroquinolactacide (6), which had previously been described as a synthetic compound. In addition, 13 known compounds including seven alkaloids and six polyketides were isolated. The structures of the new compounds were unambiguously determined on the basis of one- and two-dimensional NMR spectroscopy as well as by high-resolution mass spectrometry. Citriquinochroman (1) features a new skeleton, consisting of quinolactacide and (3S)-6-hydroxy-8-methoxy-3,5-dimethylisochroman linked by a C-C bond. 1,2,3,11b-Tetrahydroquinolactacide (6) may be a biogenetic precursor of quinolactacide. Citriquinochroman (1) showed cytotoxicity against the murine lymphoma L5178Y cell line with an IC50 value of 6.1 µM, while the other compounds were inactive (IC50 >10 µM) in this assay.


Asunto(s)
Alcaloides/aislamiento & purificación , Antineoplásicos Fitogénicos/aislamiento & purificación , Fabaceae/microbiología , Penicillium/química , Policétidos/aislamiento & purificación , Alcaloides/química , Alcaloides/farmacología , Animales , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Escherichia coli/efectos de los fármacos , Ratones , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Marruecos , Resonancia Magnética Nuclear Biomolecular , Policétidos/química , Policétidos/farmacología , Staphylococcus aureus/efectos de los fármacos , Streptococcus pneumoniae/efectos de los fármacos
14.
Z Naturforsch C J Biosci ; 68(7-8): 269-74, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24066511

RESUMEN

Phytochemical investigation of Aglaia duppereana flowers led to the isolation of a new rocaglamide derivative and twelve known congeners. The structure of the new compound was unambiguously elucidated by spectroscopic techniques (1D- and 2D-NMR, HRESIMS). The isolated compounds exhibited a potent cytotoxic activity against mouse lymphoma (L5178Y) cells with EC50 values ranging from 5.1 to 54.8 nM.


Asunto(s)
Aglaia/química , Antineoplásicos Fitogénicos/farmacología , Benzofuranos/farmacología , Animales , Antineoplásicos Fitogénicos/química , Benzofuranos/química , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Espectroscopía de Resonancia Magnética , Ratones , Estructura Molecular , Espectrometría de Masa por Ionización de Electrospray
15.
Nat Prod Res ; 37(16): 2662-2671, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36194212

RESUMEN

Vanillin (1), the main constituent of vanilla species, was used as a starting natural scaffold for the synthesis of five new (2-6) and one known (7) triazole derivatives via click chemistry using the copper (I)-catalyzed azide-alkyne cycloaddition method. Vanillin and its new derivatives; 4-{1-[2-Hydroxymethyl-5-(5 methyl-2,4-dioxo-3,4-dihydro-2H-pyrimidin-1-yl)-tetrahydro-furan-3-yl]-1H[1,2,3]triazol-4-ylmethoxy}-3-methoxy-benzaldehyde (2); [4-(4-Formyl-2methoxy-phenoxymethyl)-[1,2,3]triazol-1-yl]-acetic acid methyl ester (3); 4-[1-(4-Acetyl-phenyl)-1H-[1,2,3]triazol-4-ylmethoxy]-3-methoxy-benzaldehyde (4); 4-[4-(1-Benzyl-1H-[1,2,3]triazol-4-ylmethoxy)-3-methoxy-phenyl]-but-3-en-2-one (5); and 4-[4-(1-Benzyl-1H-[1,2,3]triazol-4-ylmethoxy)-3-methoxy-phenyl]-4-hydroxy-butan-2-one (6), as well as the previously known derivative (7) were subjected to antimicrobial, antiquorum-sensing and cytotoxic evaluation. Compounds 4-7 possessed the most notable enhancement in the anti-bacterial activity against Bacillus cereus, Pseudomonas aeruginosa and antifungal activity against Candida albicans. However, compounds 1 and 2 exhibited high antiquorum-sensing activity against Chromobacterium violaceum using catechin as a positive control. Compounds 4-7 demonstrated selective cytotoxicity against MCF-7 and HepG2 cancer cells compared to normal lung fibroblast cells (WI-38). These findings proved the usefulness of synthesis bioactive derivatives from vanillin through chemical modifications.

16.
Materials (Basel) ; 16(7)2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-37049139

RESUMEN

A radiation source based on the inertial electrostatic confinement fusion (IECF) system is being developed for multidisciplinary research applications. The radiation outputs from the IECF system are 2.45 MeV fast neutrons and the associated co-generated X-rays with an energy less than 3 MeV. A radiation shielding study has been performed on five types of concrete to define the most efficient material for the shielding design of the system. The proposed materials were ilmenite-magnetite concrete (IMC), ordinary concrete-1 (OC-1), barite-containing concrete (BC), ordinary concrete-2 (OC-2), and serpentine-containing concrete (SC). A numerical model was applied to determine the effective removal cross-section coefficients (∑Rt) for the fast neutrons and the total mass attenuation coefficients (µm), the half-value layer (HVL), the mean free path (MFP), the effective atomic number (Zeff), and effective electron density (Neff) for photons inside the materials. The model considered the radiation source energy and the material properties of the concrete types. The results revealed that the serpentine-containing concrete exhibited the highest ∑Rt with 12 cm of concrete thickness needed to attenuate an incident neutron flux to 1/100 of its initial value. In addition, the BC shows the highest µm with a 38 cm concrete thickness needed to attenuate the 3 MeV energy X-ray flux to 1/100 of its initial value. This study suggests that a 40 cm thickness of SC or BC adequately shields the radiation generated from an IECF system with a maximum particle production rate of up to 1 × 107 n/s.

17.
Micromachines (Basel) ; 14(9)2023 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-37763895

RESUMEN

This paper introduces a novel two-port ultra-wideband (UWB) multiple-input multiple-output (MIMO) antenna system with enhanced isolation characteristics. The antenna, designed on a thin 0.787 mm RO5880 substrate, achieves a compact form factor of 52 × 26 mm2 and offers a wide bandwidth of 9.2 GHz (2.3 GHz to 11.5 GHz) while meeting the VSWR 2:1 criterion. Notably, the proposed antenna demonstrates an impressive increase in isolation, up to 16 dB, through the integration of a shared radiator with small rectangular slots, effectively reducing interference and improving overall performance. Furthermore, a comprehensive analysis of additional MIMO performance parameters, including the envelope correlation coefficient (ECC) and diversity gain, confirms their satisfactory limits, validating the potential of the proposed UWB-MIMO antenna for various UWB applications. The time domain analysis of the UWB antenna is also analyzed, and results are found to be within satisfactory limits. Simulation and measurement results further support the practicality and effectiveness of the antenna design, highlighting its compact size, wide bandwidth, and enhanced isolation characteristics, positioning it as a promising solution for advanced UWB microwave imaging systems.

18.
Micromachines (Basel) ; 14(4)2023 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-37421009

RESUMEN

In this article, we propose a light weight, low profile Multiple Input Multiple Output (MIMO) antenna system for compact 5th Generation (5G) mmwave devices. Using a RO5880 substrate that is incredibly thin, the suggested antenna is made up of circular rings stacked vertically and horizontally on top of one another. The single element antenna board has dimensions of 12 × 12 × 0.254 mm3 while the size of the radiating element is 6 × 2 × 0.254 mm3 (0.56λ0 × 0.19λ0 × 0.02λ0). The proposed antenna showed dual band characteristics. The first resonance showed a bandwidth of 10 GHz with a starting frequency of 23 GHz to an ending frequency point of 33 GHz followed by a second resonance bandwidth of 3.25 GHz ranging from 37.75 to 41 GHz, respectively. The proposed antenna is transformed into a four element Linear array system with size of 48 × 12 × 0.254 mm3 (4.48λ0 × 1.12λ0 × 0.02λ0). The isolation levels at both resonance bands were noted to be >20 dB which shows high levels of isolation among radiating elements. The MIMO parameters such as Envelope Correlation Co-efficient (ECC), Mean Effective Gain (MEG) and Diversity Gain (DG) were derived and were found to be in satisfactory limits. The proposed MIMO system model is fabricated and through validation and testing of the prototype, the results were found to be in good agreement with simulations.

19.
Neurosurgery ; 92(1): 118-124, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36170173

RESUMEN

BACKGROUND: The use of flow diverters for treating intracranial aneurysms has been widely used in the past decade; however, data comparing pipeline embolization device (PED; Medtronic Inc) and flow-redirection endoluminal device (FRED; MicroVention) in the treatment of intracranial aneurysms remain scarce. OBJECTIVE: To compare the outcomes of PED and FRED in the treatment of intracranial aneurysms. METHODS: This is a single-center retrospective review of aneurysms treated with PED and FRED devices. Patients treated with PED or FRED were included. Cases requiring multiple or adjunctive devices were excluded. Primary outcome was complete aneurysm occlusion at 6 months. Secondary outcomes included good functional outcome, need for retreatment, and any complication. RESULTS: The study cohort comprised 150 patients, including 35 aneurysms treated with FRED and 115 treated with PED. Aneurysm characteristics including location and size were comparable between the 2 cohorts. 6-month complete occlusion rate was significantly higher in the PED cohort (74.7% vs 51.5%; P = .017) but lost significance after inverse probability weights. Patients in the PED cohort were associated with higher rates of periprocedural complications (3.5% vs 0%; P = .573), and the rate of in-stent stenosis was approximately double in the FRED cohort (15.2% vs 6.9%; P = .172). CONCLUSION: Compared with PED, FRED offers modest 6-month occlusion rates, which may be due to aneurysmal and baseline patient characteristics differences between both cohorts. Although not significant, FRED was associated with a higher complication rate mostly because of in-stent stenosis. Additional studies with longer follow-up durations should be conducted to further evaluate FRED thrombogenicity.


Asunto(s)
Embolización Terapéutica , Procedimientos Endovasculares , Aneurisma Intracraneal , Humanos , Aneurisma Intracraneal/terapia , Aneurisma Intracraneal/etiología , Constricción Patológica/etiología , Resultado del Tratamiento , Prótesis Vascular , Estudios Retrospectivos , Estudios de Seguimiento
20.
J Neurointerv Surg ; 15(11): 1072-1077, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36597932

RESUMEN

BACKGROUND: Endovascular thrombectomy (EVT) has become the mainstay treatment for large vessel occlusion, with favorable safety and efficacy profile. However, the safety and efficacy of EVT in concurrent multi-territory occlusions (MTVOs) remains unclear. OBJECTIVE: To investigate the prevalence, clinical and technical outcomes of concurrent EVT for MTVOs. METHODS: Data were included from the Stroke Thrombectomy and Aneurysm Registry (STAR) with 32 stroke centers for EVT performed to treat bilateral anterior or concurrent anterior and posterior circulation occlusions between 2017 and 2021. Patients with MTVO were identified, and propensity score matching was used to compare this group with patients with occlusion in a single arterial territory. RESULTS: Of a total of 7723 patients who underwent EVT for acute ischemic stroke, 54 (0.7%) underwent EVT for MTVOs (mean age 69±12.5; female 50%). 28% had bilateral and 72% had anterior and posterior circulations occlusions. The rate of successful recanalization (Thrombolysis in Cerebral Infarction 2b/3), complications, modified Rankin score at 90 days, and mortality was not significantly different between the matched cohorts. Multivariate analysis confirmed that MTVOs were not associated with poor functional outcome, symptomatic intracranial hemorrhage, or longer procedure time. CONCLUSION: Compared with EVT for single vessel occlusions, EVT in appropriately selected patients with MTVOs has a similar efficacy and safety profile.

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