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1.
J Surg Case Rep ; 2024(6): rjae389, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38832063

RESUMO

Meningiomas, typically benign neoplasms originating in the central nervous system, display a predilection for female patients. Although they predominantly manifest within the cranial vault, ~25% of primary spinal neoplasms are attributed to these tumors. The occurrence of ossification in spinal meningiomas is an uncommon phenomenon, with scant documentation in medical literature. In this report, we detail the clinical journey of an octogenarian female patient afflicted with an ossified spinal meningioma, which was associated with left lower extremity weakness and reduced sensation. Diagnostic imaging, specifically magnetic resonance imaging, identified a mass exerting pressure on the spinal cord, necessitating its surgical removal. Subsequent histopathological examinations corroborated the initial diagnosis. Postoperative magnetic resonance imaging scans confirmed the absence of residual tumor tissue and ruled out recurrence. A comprehensive review of existing literature yielded 47 analogous cases, with a majority involving elderly female patients and the thoracic region of the spine being the most common site. The standard therapeutic approach is surgical intervention, which is often complicated by the tumor's tenacious adherence to surrounding structures and the potential for ensuing operative complications. This case highlights the exceptional nature of ossified spinal meningiomas and emphasizes the critical need for meticulous surgical management.

3.
Clin Park Relat Disord ; 10: 100234, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38292816

RESUMO

Background and Objectives: Deep brain stimulation (DBS) is a well-established surgical treatment for certain movement disorders and involves the implantation of brain electrodes connected to implantable pulse generators (IPGs). As more device manufacturers have entered the market, some IPG technology has been designed to be compatible with brain electrodes from other manufacturers, which has facilitated the hybridization of implant technology. The aim of this study was to assess the benefits of hybridization of non-rechargeable, constant voltage IPGs to rechargeable, constant current IPGs. Methods: A list of DBS movement disorder patients who had their non-rechargeable, constant voltage IPGs replaced with rechargeable, constant current IPGs from a different manufacturer was compiled. Structured surveys of these patients, and their caregivers when applicable, were undertaken to determine both patient and caregiver satisfaction in this DBS hybridization strategy. Results: Eighteen patients met inclusion criteria and twelve patients or their caregivers completed the structured survey (67% response rate). Nine patients had Parkinson's disease (75%), three had essential tremor (25%). Nine (75%) were converted from bilateral single-channel IPGs, and three (25%) were converted from a unilateral dual-channel IPGs. Overall, 92% of patients and caregivers surveyed reported improvement or no change in their symptoms, 92% reported a decrease or no change in their medication requirements, and 92% report they are satisfied or very satisfied with their IPG hybridization and would recommend the surgery to similar patients. There were no immediate surgical complications. Conclusion: In this series of movement disorder DBS patients, surgery was safe and patient and caregiver satisfaction were high with a hybridization of non-rechargeable, constant voltage IPGs to rechargeable, constant current IPGs.

4.
J Neurosurg Case Lessons ; 6(26)2023 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-38145559

RESUMO

BACKGROUND: Tophaceous gout is a severe form of gout that results in the formation of large nodules, or tophi, in the affected joints and surrounding tissues. Gouty tophi in the spine have a constellation of presentations that often mimic other pathologies and may not be easily discernable from more common pathologic processes. OBSERVATIONS: A 47-year-old female with a history of chronic renal disease, obesity, gout, inflammatory polyarthritis, and multiple sclerosis presented with 6 months of low-back pain and lumbar radiculopathy affecting the right lower extremity. A lumbar magnetic resonance imaging study revealed right foraminal stenosis and spondylolisthesis at levels L4-5. An intraspinal extradural mass was noted adjacent to the traversing right L5 and exiting right L4 nerve roots. A bilateral decompressive laminectomy, facetectomy, and foraminotomy of L4-5 was performed. A calcific, chalky-white mass was discovered in the foramen, and pathology determined the specimen to be a gout tophus. Postoperatively, the patient endorsed the resolution of her preoperative symptoms, which have not returned on follow-up. LESSONS: Reports of gouty depositions compressing the spinal cord in the current literature are relatively rare. Although the diagnosis of gouty tophi can only be confirmed histologically, patient history may serve as a helpful diagnostic tool.

5.
ArXiv ; 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37961731

RESUMO

Purpose: To study the effect of proton linear energy transfer (LET) on rib fracture in breast cancer patients treated with pencil-beam scanning proton therapy (PBS) using a novel tool of dose-LET volume histogram (DLVH). Methods: From a prospective registry of patients treated with post-mastectomy proton therapy to the chest wall and regional lymph nodes for breast cancer between 2015 and 2020, we retrospectively identified rib fracture cases detected after completing treatment. Contemporaneously treated control patients that did not develop rib fracture were matched to patients 2:1 considering prescription dose, boost location, reconstruction status, laterality, chest wall thickness, and treatment year.The DLVH index, V(d, l), defined as volume(V) of the structure with at least dose(d) and LET(l), was calculated. DLVH plots between the fracture and control group were compared. Conditional logistic regression (CLR) model was used to establish the relation of V(d, l) and the observed fracture at each combination of d and l. The p-value derived from CLR model shows the statistical difference between fracture patients and the matched control group. Using the 2D p-value map derived from CLR model, the DLVH features associated with the patient outcomes were extracted. Results: Seven rib fracture patients were identified, and fourteen matched patients were selected for the control group. The median time from the completion of proton therapy to rib fracture diagnosis was 12 months (range 5 to 14 months). Two patients had grade 2 symptomatic rib fracture while the remaining 5 were grade 1 incidentally detected on imaging. The derived p-value map demonstrated larger V(0-36Gy[RBE], 4.0-5.0 keV/µm) in patients experiencing fracture (p<0.1). For example, the p value for V(30 Gy[RBE], 4.0 keV/um) was 0.069. Conclusions: In breast cancer patients receiving PBS, a larger volume of chest wall receiving moderate dose and high LET may result in increased risk of rib fracture.

6.
Cureus ; 15(10): e47443, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38022023

RESUMO

We present the case of a 53-year-old male with complicated left-sided parapneumonic effusion due to Streptococcus intermedius and Prevotella buccae. Management required video-assisted thoracoscopic surgery and partial decortication of the left lung. Complications during the hospital stay were extensive, including sepsis, acute hypoxic respiratory failure, alcohol withdrawal, and transient ischemic attack.

7.
Int J Radiat Oncol Biol Phys ; 117(4): 1018-1027, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37364800

RESUMO

PURPOSE: This work describes the first implementation and in vivo study of ultrahigh-dose-rate radiation (>37 Gy/s; FLASH) effects induced by kilovoltage (kV) x-ray from a rotating-anode x-ray source. METHODS AND MATERIALS: A high-capacity rotating-anode x-ray tube with an 80-kW generator was implemented for preclinical FLASH radiation research. A custom 3-dimensionally printed immobilization and positioning tool was developed for reproducible irradiation of a mouse hind limb. Calibrated Gafchromic (EBT3) film and thermoluminescent dosimeters (LiF:Mg,Ti) were used for in-phantom and in vivo dosimetry. Healthy FVB/N and FVBN/C57BL/6 outbred mice were irradiated on 1 hind leg to doses up to 43 Gy at FLASH (87 Gy/s) and conventional (CONV; <0.05 Gy/s) dose rates. The radiation doses were delivered using a single pulse with the widths up to 500 ms and 15 minutes at FLASH and CONV dose rates. Histologic assessment of radiation-induced skin damage was performed at 8 weeks posttreatment. Tumor growth suppression was assessed using a B16F10 flank tumor model in C57BL6J mice irradiated to 35 Gy at both FLASH and CONV dose rates. RESULTS: FLASH-irradiated mice experienced milder radiation-induced skin injuries than CONV-irradiated mice, visible by 4 weeks posttreatment. At 8 weeks posttreatment, normal tissue injury was significantly reduced in FLASH-irradiated animals compared with CONV-irradiated animals for histologic endpoints including inflammation, ulceration, hyperplasia, and fibrosis. No difference in tumor growth response was observed between FLASH and CONV irradiations at 35 Gy. The normal tissue sparing effects of FLASH irradiations were observed only for high-severity endpoint of ulceration at 43 Gy, which suggests the dependency of biologic endpoints to FLASH radiation dose. CONCLUSIONS: Rotating-anode x-ray sources can achieve FLASH dose rates in a single pulse with dosimetric properties suitable for small-animal experiments. We observed FLASH normal tissue sparing of radiation toxicities in mouse skin irradiated at 35 Gy with no sacrifice to tumor growth suppression. This study highlights an accessible new modality for laboratory study of the FLASH effect.


Assuntos
Neoplasias , Lesões por Radiação , Animais , Camundongos , Raios X , Camundongos Endogâmicos C57BL , Radiografia , Radiometria
8.
Int J Radiat Oncol Biol Phys ; 117(4): 846-856, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37244627

RESUMO

PURPOSE: To report oncologic, physician-assessed, and patient-reported outcomes (PROs) for a group of women homogeneously treated with modern, skin-sparing multifield optimized pencil-beam scanning proton (intensity modulated proton therapy [IMPT]) postmastectomy radiation therapy (PMRT). METHODS AND MATERIALS: We reviewed consecutive patients who received unilateral, curative-intent, conventionally fractionated IMPT PMRT between 2015 and 2019. Strict constraints were applied to limit the dose to the skin and other organs at risk. Five-year oncologic outcomes were analyzed. Patient-reported outcomes were evaluated as part of a prospective registry at baseline, completion of PMRT, and 3 and 12 months after PMRT. RESULTS: A total of 127 patients were included. One hundred nine (86%) received chemotherapy, among whom 82 (65%) received neoadjuvant chemotherapy. The median follow-up was 4.1 years. Five-year locoregional control was 98.4% (95% CI, 93.6-99.6), and overall survival was 87.9% (95% CI, 78.7-96.5). Acute grade 2 and 3 dermatitis was seen in 45% and 4% of patients, respectively. Three patients (2%) experienced acute grade 3 infection, all of whom had breast reconstruction. Three late grade 3 adverse events occurred: morphea (n = 1), infection (n = 1), and seroma (n = 1). There were no cardiac or pulmonary adverse events. Among the 73 patients at risk for PMRT-associated reconstruction complications, 7 (10%) experienced reconstruction failure. Ninety-five patients (75%) enrolled in the prospective PRO registry. The only metrics to increase by >1 point were skin color (mean change: 5) and itchiness (2) at treatment completion and tightness/pulling/stretching (2) and skin color (2) at 12 months. There was no significant change in the following PROs: bleeding/leaking fluid, blistering, telangiectasia, lifting, arm extension, or bending/straightening the arm. CONCLUSIONS: With strict dose constraints to skin and organs at risk, postmastectomy IMPT was associated with excellent oncologic outcomes and PROs. Rates of skin, chest wall, and reconstruction complications compared favorably to previous proton and photon series. Postmastectomy IMPT warrants further investigation in a multi-institutional setting with careful attention to planning techniques.

9.
Cell Rep ; 42(5): 112422, 2023 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-37099422

RESUMO

Humans use predictions to improve speech perception, especially in noisy environments. Here we use 7-T functional MRI (fMRI) to decode brain representations of written phonological predictions and degraded speech signals in healthy humans and people with selective frontal neurodegeneration (non-fluent variant primary progressive aphasia [nfvPPA]). Multivariate analyses of item-specific patterns of neural activation indicate dissimilar representations of verified and violated predictions in left inferior frontal gyrus, suggestive of processing by distinct neural populations. In contrast, precentral gyrus represents a combination of phonological information and weighted prediction error. In the presence of intact temporal cortex, frontal neurodegeneration results in inflexible predictions. This manifests neurally as a failure to suppress incorrect predictions in anterior superior temporal gyrus and reduced stability of phonological representations in precentral gyrus. We propose a tripartite speech perception network in which inferior frontal gyrus supports prediction reconciliation in echoic memory, and precentral gyrus invokes a motor model to instantiate and refine perceptual predictions for speech.


Assuntos
Córtex Motor , Fala , Humanos , Fala/fisiologia , Mapeamento Encefálico , Lobo Frontal/fisiologia , Encéfalo , Lobo Temporal , Imageamento por Ressonância Magnética/métodos
10.
Int J Part Ther ; 9(3): 10-17, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36721479

RESUMO

Purpose: To compare Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE) in patients with endometrial cancer receiving adjuvant pelvic radiation therapy with proton beam therapy (PT) versus intensity-modulated radiation therapy (IMRT). Materials and Methods: Patients with uterine cancer treated with curative intent who received either adjuvant PT or IMRT between 2014 and 2020 were identified. Patients were enrolled into a prospective registry using a gynecologic-specific subset of PRO-CTCAE designed to assess symptom impact on daily living. Questions included gastrointestinal (GI) symptoms of diarrhea, flatulence, bowel incontinence, and constipation in addition to other pertinent gynecologic, urinary, and other general symptoms. Symptom-based questions were on a 0- to 4-point scale, with grade 3+ symptoms occurring frequently or almost always. Patient-reported toxicity was analyzed at baseline, end of treatment (EOT), and at 3, 6, 9, and 12 months after treatment. Unequal variance t tests were used to determine if treatment type was a significant factor in baseline-adjusted PRO-CTCAE. Results: Sixty-seven patients met inclusion criteria. Twenty-two received PT and 45 patients received IMRT. Brachytherapy boost was delivered in 73% of patients. Median external beam dose was 45 Gy for both PT and IMRT (range, 45-58.8 Gy). When comparing PRO-CTCAE, PT was associated with less diarrhea at EOT (P = .01) and at 12 months (P = .24) than IMRT. Loss of bowel control at 12 months was more common in patients receiving IMRT (P = .15). Any patient reporting grade 3+ GI toxicity was noted more frequently with IMRT (31% versus 9%, P = .09). Discussion: Adjuvant PT is a promising treatment for patients with uterine cancer and may reduce patient-reported GI toxicity as compared with IMRT.

11.
Transl Lung Cancer Res ; 11(8): 1578-1590, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36090640

RESUMO

Background: Cell free DNA (cfDNA) is an exciting biomarker with applications across the cancer care continuum. Determinants of cfDNA shedding dynamics remain an active research area. We performed a detailed analysis of tumor volume and factors associated with detection of cfDNA mutations. Methods: Patients with advanced non-small cell lung cancers (NSCLCs) were prospectively enrolled on a plasma biomarker protocol. Next generation sequencing (NGS) was performed using a validated, bias-corrected, hybrid-capture panel assay of lung cancer-associated genes. Volume of tumor in different subsites and total tumor volume were determined through manual volume delineation using PET/CT and brain magnetic resonance imaging (MRI) imaging. The primary endpoint was detection of cfDNA mutation; secondary endpoints were overall survival (OS) and variant allele frequency (VAF). Results: There were 110 patients included, 78 of whom had at least one mutation detected. Median total tumor volume for the entire cohort, patients with mutation detected, and patients with no mutation detected were 66 mL (range, 2-1,383 mL), 76 mL (range, 5-1,383 mL), and 45 mL (range, 2-460 mL), respectively (P=0.002; mutation detected vs. not). The optimal total tumor volume threshold to predict increased probability of mutation detection was 65 mL (P=0.006). Total tumor volume greater than 65 mL was a significant predictor of mutation detection on multivariate analysis (OR: 4.30, P=0.003). Significant predictors of OS were age (HR: 1.04, P=0.002), detection of cfDNA mutation (HR: 2.11, P=0.024), and presence of bone metastases (HR: 1.66, P=0.047). Conclusions: Total tumor volume greater than 65 mL was associated with cfDNA mutation detection in patients with advanced NSCLC.

12.
Radiother Oncol ; 171: 77-83, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35436537

RESUMO

PURPOSE: Inflammatory breast cancer (IBC) poses a radiotherapeutic challenge due to dermal lymphatic involvement, which often necessitates larger target volumes and chest wall boosts, making advanced planning techniques attractive to reduce exposure to nearby organs. We report our experience with intensity modulated proton therapy (IMPT) for the treatment of IBC. METHODS: Between 2016 and 2020, all IBC patients treated with adjuvant IMPT at our institution were identified. Overall survival (OS) and distant metastasis-free survival (DMFS) were estimated using the Kaplan-Meier method. Adverse events (AEs) were assessed using CTCAE version 5.0. RESULTS: Nineteen patients were identified with median 24-month follow-up. CTVs included skin, chest wall, and regional lymph nodes. Median dose was 50 Gy in 25 fractions, with fifteen receiving chest wall boost (median 56.25 Gy in 25 fractions). During treatment, plan re-optimization was required in 9 (47%). Acute grade 3 dermatitis occurred in 2 (11%). Rib facture occurred in 4 (21%). One patient with pre-existing surgical seroma experienced a grade 3 fistula. Mean heart, left anterior descending artery, and right coronary artery doses were 0.7 Gy, 2.3 Gy, and 0.1 Gy, respectively. Mean ipsilateral lung V20Gy was 14.9%. At 2 years, there were no locoregional recurrences, and OS and DMFS were 89% and 82%, respectively. CONCLUSION: IMPT for IBC is well-tolerated with excellent dosimetry, low rates of AEs, and favorable early locoregional control outcomes. Follow-up for long-term outcomes is ongoing. Our findings suggest that IMPT is feasible and an attractive modality worthy of further investigation in patients with IBC.


Assuntos
Neoplasias da Mama , Neoplasias Inflamatórias Mamárias , Terapia com Prótons , Radioterapia de Intensidade Modulada , Neoplasias da Mama/etiologia , Feminino , Humanos , Neoplasias Inflamatórias Mamárias/etiologia , Neoplasias Inflamatórias Mamárias/radioterapia , Recidiva Local de Neoplasia/etiologia , Terapia com Prótons/efeitos adversos , Terapia com Prótons/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos
13.
Cureus ; 14(1): e21172, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35165621

RESUMO

A 64-year-old male presented with spontaneous intracerebral hemorrhage and obstructive hydrocephalus without evidence of a third ventricular mass in 2019. The patient was lost to follow-up and re-admitted one year later for hydrocephalus secondary to a third ventricular mass. Imaging characteristics were consistent with a colloid cyst, which was the presumptive diagnosis. A transcallosal transchoroidal approach was utilized for cyst resection. The cyst wall was carefully incised, releasing flakey, partially solid contents which were grossly inconsistent with a colloid cyst. Due to the concern of iatrogenic cyst rupture in the setting of unknown diagnosis, the patient was placed on steroids post-operatively. Surgical specimens sent at the time of surgery were consistent with dermoid cyst. We present the first reported case of a third ventricular dermoid cyst in an adult initially misdiagnosed as a colloid cyst based on imaging characteristics.

14.
Eur J Dent ; 16(3): 619-626, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34879396

RESUMO

OBJECTIVES: To compare the changes in implant stability for the nonsubmerged and submerged protocols for a single-implant retained mandibular overdenture using Cendres and Metaux Locator attachment throughout a 24-month follow-up. MATERIALS AND METHODS: Eighty edentulous patients who were seeking to install a single implant in the midline of the completely edentulous mandible. At the day of implant installation, patients were randomized into two groups using sealed envelopes: the nonsubmerged and submerged groups. After 3 months of healing period, randomization using sealed envelopes was performed and patients were randomized to receive the Cendres and Metaux Locator attachment. The periotest readings were recorded using the Periotest M device, every 3 months for the first year and annually in the second year. The scope of this clinical trial focused only on results of the Cendres and Metaux attachment. STATISTICAL ANALYSIS: The Mann-Whitney U-test was used for comparison between study groups for independent samples. Two-sided p-values less than 0.05 were considered statistically significant. RESULTS: There was no statistically significant difference between the mean periotest readings of both groups throughout the 24-month follow-up. Both groups showed an improvement in mean periotest readings with the submerged group tending to show greater stability at 6, 12, and 24-month follow-ups. CONCLUSIONS: The nonsubmerged and the submerged healing protocols resulted in reliable periotest readings with the submerged group showing greater improvement than the nonsubmerged, although this improvement is nonsignificant when using the Cendres and Metaux attachment for a single mandibular overdenture.

15.
J Ind Text ; 51(1 Suppl): 246S-271S, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38603366

RESUMO

The novel coronavirus disease (COVID-19) has generated great confusion around the world, affecting people's lives and producing a large number of deaths. The development of portable and wearable devices is of great importance in several fields such as point-of-care medical applications and environmental monitoring. Wearable devices with an ability to collect various types of physiological records are progressively becoming incorporated into everyday life of people. Physiological indicators are essential health indicators and their monitoring could efficiently enable early discovery of disease. This would also help decrease the number of extra severe health problems, in disease avoidance, and lower the overall public sector health cost. Protective clothing is nowadays a main part of textiles classified as technical or industrial textiles. Protective clothing aims to protect its wearer from the harsh environmental impacts that may result in injury or death. Providing protection for the common population has also been taken seriously considering the anticipated disaster due to virus attacks. This review highlights the properties of the materials that are used in wearable health care device and medical textiles.

16.
Br J Neurosurg ; : 1-7, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34240676

RESUMO

INTRODUCTION: Laser interstitial thermal therapy (LITT) is a minimally invasive treatment method in managing primary brain neoplasms, brain metastases, radiation necrosis, and epileptogenic lesions, many of which are located in operative corridors that would be difficult to address. Although the use of lasers is not a new concept in neurosurgery, advances in technology have enabled surgeons to perform laser treatment with the aid of real-time MRI thermography as a guide. In this report, we present our institutional series and outcomes of patients treated with LITT. METHODS: We retrospectively evaluated 19 patients (age range, 28-77 years) who underwent LITT at one or more targets from 2015 to 2019. Primary endpoint observed was mean progression free survival (PFS) and overall survival (OS). RESULTS: Seven patients with glial neoplasms and 12 patients with metastatic disease were reviewed. Average hospitalization was 2.4 days. Median PFS was 7 and 4 months in the metastatic group and primary glial neoplasm group, respectively (p = 0.01). Median OS from time of diagnosis was 41 and 32 months (p = 0.02) and median OS after LITT therapy was 25 and 24 months (p = 0.02) for the metastatic and primary glial neoplasm groups, respectively. One patient experienced immediate post-procedural morbidity secondary to increased intracerebral edema peri-lesionally while one patient experienced post-operative mortality and expired secondary to hemorrhage 1-month post-procedure. Median follow-up was 10 months. CONCLUSION: Laser interstitial thermal therapy (LITT) is a safe, minimally invasive treatment method that provides surgeons with cytoreductive techniques to treat neurosurgical conditions. Both PFS and OS appear to be more favorable after LITT in patients with metastatic disease. In properly selected patients, this modality offers improved survival outcomes in conjunction with other salvage therapies.

17.
Sci Prog ; 104(2): 368504211029469, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34191657

RESUMO

Aluminum alloys are the most essential part of all shaped castings manufactured, mainly in the automotive, food industry, and structural applications. There is little consensus as to the precise relationship between grain size after grain refinement and corrosion resistance; conflicting conclusions have been published showing that reduced grain size can decrease or increase corrosion resistance. The effect of Al-5Ti-1B grain refiner (GR alloy) with different percentages on the mechanical properties and corrosion behavior of Aluminum-magnesium-silicon alloy (Al-Mg-Si) was studied. The average grain size is determined according to the E112ASTM standard. The compressive test specimens were made as per ASTM: E8/E8M-16 standard to get their compressive properties. The bulk hardness using Vickers hardness testing machine at a load of 50 g. Electrochemical corrosion tests were carried out in 3.5 % NaCl solution using Autolab Potentiostat/Galvanostat (PGSTAT 30).The grain size of the Al-Mg-Si alloy was reduced from 82 to 46 µm by the addition of GR alloy. The morphology of α-Al dendrites changes from coarse dendritic structure to fine equiaxed grains due to the addition of GR alloy and segregation of Ti, which controls the growth of primary α-Al. In addition, the mechanical properties of the Al-Mg-Si alloy were improved by GR alloy addition. GR alloy addition to Al-Mg-Si alloy produced fine-grained structure and better hardness and compressive strength. The addition of GR alloy did not reveal any marked improvements in the corrosion properties of Al-Mg-Si alloy.

19.
Surg Neurol Int ; 11: 186, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32754358

RESUMO

BACKGROUND: The minimally invasive approaches to the anterior skull base region through fronto-orbital craniotomy remain a highly accepted option that gains countenance and predilection over time. The transpalpebral "eyelid" incision is an under-utilized and more recent technique that offers a safe efficient corridor to manage a wide variety of lesions. METHODS: We carried a retrospective study of 44 patients operated on by the fronto-orbital craniotomy through transpalpebral "eyelid" incision for intracranial tumors, in the time period from March 2007 to July 2016. The results from surgeries were analyzed; extent of tumor resection, length of hospital stay, cosmetic outcome, and complications. RESULTS: Out of the 44 intracranial tumor cases, we had 16 male and 28 female patients with median age 54 years. We had 19 anterior skull base lesions, 8 middle skull base lesions and 8 parasellar lesions. We also operated on four frontal intraparenchymal lesions and four other various lesions. Total resection was achieved in 32 cases (72.7%), with excellent cosmetic outcome in 43 cases (97.7%). Average hospital stay was 6 days. No major complications recorded. Three cases (6.8%) had complications that varied between pseudomeningocele, wound infections, and facial pain. Follow-up average period was 23.6 months. CONCLUSION: The fronto-orbital approach through eyelid incision remains a reliable approach to the skull base. It provides natural anatomical dissection planes through the eyelid incision and a fronto-orbital craniotomy, creating a wide surgical corridor to manage specific lesions with consistent surgical and cosmetic outcome.

20.
Transl Oncol ; 13(4): 100755, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32197147

RESUMO

BACKGROUND: Chemotherapy-resistant cancer stem cells (CSC) may lead to tumor recurrence in glioblastoma (GBM). The poor prognosis of this disease emphasizes the critical need for developing a treatment stratification system to improve outcomes through personalized medicine. METHODS: We present a case series of 12 GBM and 2 progressive anaplastic glioma cases from a single Institution prospectively treated utilizing a CSC chemotherapeutics assay (ChemoID) guided report. All patients were eligible to receive a stereotactic biopsy and thus undergo ChemoID testing. We selected one of the most effective treatments based on the ChemoID assay report from a panel of FDA approved chemotherapy as monotherapy or their combinations for our patients. Patients were evaluated by MRI scans and response was assessed according to RANO 1.1 criteria. RESULTS: Of the 14 cases reviewed, the median age of our patient cohort was 49 years (21-63). We observed 6 complete responses (CR) 43%, 6 partial responses (PR) 43%, and 2 progressive diseases (PD) 14%. Patients treated with ChemoID assay-directed therapy, in combination with other modality of treatment (RT, LITT), had a longer median overall survival (OS) of 13.3 months (5.4-NA), compared to the historical median OS of 9.0 months (8.0-10.8 months) previously reported. Notably, patients with recurrent GBM or progressive high-grade glioma treated with assay-guided therapy had a 57% probability to survive at 12 months, compared to the 27% historical probability of survival observed in previous studies. CONCLUSIONS: The results presented here suggest that the ChemoID Assay has the potential to stratify individualized chemotherapy choices to improve recurrent and progressive high-grade glioma patient survival. IMPORTANCE OF THE STUDY: Glioblastoma (GBM) and progressive anaplastic glioma are the most aggressive brain tumor in adults and their prognosis is very poor even if treated with the standard of care chemoradiation Stupp's protocol. Recent knowledge pointed out that current treatments often fail to successfully target cancer stem cells (CSCs) that are responsible for therapy resistance and recurrence of these malignant tumors. ChemoID is the first and only CLIA (clinical laboratory improvements amendment) -certified and CAP (College of American Pathologists) -accredited chemotherapeutic assay currently available in oncology clinics that examines patient's derived CSCs susceptibility to conventional FDA (Food and Drugs Administration) -approved drugs. In this study we observed that although the majority of our patients (71.5%) presented with unfavorable prognostic predictors (wild type IDH-1/2 and unmethylated MGMT promoter), patients treated with ChemoID assay-directed therapy had an overall response rate of 86% and increased median OS of 13.3 months compared to the historical median OS of 9.1 months (8.1-10.1 months) previously reported [1] suggesting that the ChemoID assay may be beneficial in personalizing treatment strategies.

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