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1.
Pediatr Neurosurg ; 54(4): 237-244, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31288223

RESUMO

BACKGROUND: Extradural hematoma (EDH) is one of the most common causes of mortality and morbidity after traumatic brain injury in pediatric patients. Early surgical intervention in these patients produces excellent results. OBJECTIVE: We reviewed surgical experience at our center, examining and presenting symptomatology and outcome analysis. MATERIALS AND METHODS: A retrospective study of 228 pediatric patients of EDH from July 2007 to August 2017 was performed. Patients were evaluated in terms of demographic profile, clinical features, pupillary size and reaction, computed tomography findings, operative measures, and several other parameters. Neurological status was assessed using motor component (M) of Glasgow Coma Scale score. Best motor response was considered as a criterion to classify severity of traumatic brain injury and for the assessment of outcome. RESULTS: Most of the patients were in the age group of 13-18 years (n = 122, 53.5%). Majority of them were male (n = 182, 79.8%). The commonest mode of injury was fall from height (n = 116, 50.9%) followed by road traffic accident (n = 92, 40.4%). Most common site of hematoma was frontal region (n = 66, 28.9%) followed by parietal region (n = 54, 23.7%). The volume of hematoma was between 30 and 50 mL in majority of the patients (n = 186, 81.6%), and most of the patients had a motor responses of M5 (n = 88, 38.6%) and M6 (n = 108, 47.4%). The association between hematoma site and volume was not significant (χ2 = 5.910, p = 0.749), whereas statistically significant association was noted between volume of hematoma and motor response (χ2 = 93.468, p ≤ 0.001), volume and age (χ2 = 7.380, p ≤ 0.05), and volume to time between trauma and surgery (χ2 = 8.469, p ≤ 0.05). Maximum mortality was in patients of low motor (M1-M3) response and who were operated 24 h after injury. CONCLUSION: Mortality in patients of EDH can be significantly reduced with gratifying results if operated early. Best motor response at presentation, pupillary abnormalities, time between injury to surgery, and location of hematoma have been identified as the important factors determining outcome in patients of EDH.


Assuntos
Lesões Encefálicas Traumáticas/cirurgia , Hematoma Epidural Craniano , Procedimentos Neurocirúrgicos , Acidentes por Quedas , Adolescente , Feminino , Escala de Coma de Glasgow , Hematoma Epidural Craniano/mortalidade , Hematoma Epidural Craniano/cirurgia , Humanos , Masculino , Estudos Retrospectivos , Centros de Atenção Terciária , Fatores de Tempo
2.
Pediatr Neurosurg ; 52(4): 268-270, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28601873

RESUMO

Posttraumatic hemorrhagic contusions are a common sequel of traumatic brain injuries. They occur in around 8% of all traumatic brain injuries. Spontaneous resolution of acute subdural and acute extradural hematomas, although rare, is a recognized entity, but spontaneous resolution of the hemorrhagic component of a contusion within 24 h has not been reported in the literature. We present a patient in whom the hemorrhagic component of her contusion resolved spontaneously over a period of 24 h after injury. The rarity of this case prompted us to this study.


Assuntos
Lesões Encefálicas , Contusões , Hematoma Subdural Agudo/diagnóstico por imagem , Hematoma Subdural Agudo/diagnóstico , Remissão Espontânea , Espaço Subaracnóideo , Acidentes por Quedas , Pré-Escolar , Feminino , Hematoma Subdural Agudo/etiologia , Hemorragia/diagnóstico por imagem , Humanos , Tomografia Computadorizada por Raios X
3.
Pediatr Neurosurg ; 52(2): 122-126, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28192784

RESUMO

Medulloblastoma is a common tumor of the posterior fossa, representing 20-25% of all pediatric neoplasms. It commonly occurs in the midline (cerebellar vermis) and rarely at the cerebellopontine angle. Most of them are intra-axial, and an extra-axial location of this tumor is very rare. Extra-axial cerebellopontine angle medulloblastoma is extremely uncommon and has never been reported in an infant. We report an extra-axial cerebellopontine angle medulloblastoma in a 1-year-old child.


Assuntos
Neoplasias Cerebelares/diagnóstico , Meduloblastoma/diagnóstico , Neoplasias Cerebelares/patologia , Ângulo Cerebelopontino/diagnóstico por imagem , Ângulo Cerebelopontino/patologia , Humanos , Lactente , Meduloblastoma/diagnóstico por imagem , Meduloblastoma/patologia , Tomografia Computadorizada por Raios X
4.
Pediatr Neurosurg ; 51(6): 309-312, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27513987

RESUMO

Interfrontal encephalocele is one of the rare varieties of anterior encephalocele, and a giant interfrontal encephalocele is extremely rare. The authors could find only one case report of giant interfrontal encephalocele in the literature. Anterior encephaloceles are more prevalent in South-East Asia and some northern parts of India. Giant encephalocele poses a great challenge to neurosurgeons and neuroanesthetists during surgery, as these infants usually have a low birth weight and a large sac, thus making the infant prone to hypothermia and blood loss among other risks. We encountered a patient with a giant interfrontal encephalocele aged 1 month. The rarity of this case prompted us to this report.


Assuntos
Encefalocele/diagnóstico por imagem , Encefalocele/cirurgia , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/cirurgia , Doenças Raras , Osso Frontal/diagnóstico por imagem , Osso Frontal/cirurgia , Humanos , Lactente , Masculino
5.
Materials (Basel) ; 16(4)2023 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-36837352

RESUMO

The investigation of mould inserts in the injection moulding process using metal epoxy composite (MEC) with pure metal filler particles is gaining popularity among researchers. Therefore, to attain zero emissions, the idea of recycling metal waste from industries and workshops must be investigated (waste free) because metal recycling conserves natural resources while requiring less energy to manufacture new products than virgin raw materials would. The utilisation of metal scrap for rapid tooling (RT) in the injection moulding industry is a fascinating and potentially viable approach. On the other hand, epoxy that can endure high temperatures (>220 °C) is challenging to find and expensive. Meanwhile, industrial scrap from coal-fired power plants can be a precursor to creating geopolymer materials with desired physical and mechanical qualities for RT applications. One intriguing attribute of geopolymer is its ability to endure temperatures up to 1000 °C. Nonetheless, geopolymer has a higher compressive strength of 60-80 MPa (8700-11,600 psi) than epoxy (68.95 MPa) (10,000 psi). Aside from its low cost, geopolymer offers superior resilience to harsh environments and high compressive and flexural strength. This research aims to investigate the possibility of generating a new sustainable material by integrating several types of metals in green geopolymer metal composite (GGMC) mould inserts for RT in the injection moulding process. It is necessary to examine and investigate the optimal formulation of GGMC as mould inserts for RT in the injection moulding process. With less expensive and more ecologically friendly components, the GGMC is expected to be a superior choice as a mould insert for RT. This research substantially impacts environmental preservation, cost reduction, and maintaining and sustaining the metal waste management system. As a result of the lower cost of recycled metals, sectors such as mould-making and machining will profit the most.

6.
Materials (Basel) ; 15(10)2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35629485

RESUMO

Ordinary Portland cement (OPC) is a conventional material used to construct rigid pavement that emits large amounts of carbon dioxide (CO2) during its manufacturing process, which is bad for the environment. It is also claimed that OPC is susceptible to acid attack, which increases the maintenance cost of rigid pavement. Therefore, a fly ash based geopolymer is proposed as a material for rigid pavement application as it releases lesser amounts of CO2 during the synthesis process and has higher acid resistance compared to OPC. This current study optimizes the formulation to produce fly ash based geopolymer with the highest compressive strength. In addition, the durability of fly ash based geopolymer concrete and OPC concrete in an acidic environment is also determined and compared. The results show that the optimum value of sodium hydroxide concentration, the ratio of sodium silicate to sodium hydroxide, and the ratio of solid-to-liquid for fly ash based geopolymer are 10 M, 2.0, and 2.5, respectively, with a maximum compressive strength of 47 MPa. The results also highlight that the durability of fly ash based geopolymer is higher than that of OPC concrete, indicating that fly ash based geopolymer is a better material for rigid pavement applications, with a percentage of compressive strength loss of 7.38% to 21.94% for OPC concrete. This current study contributes to the field of knowledge by providing a reference for future development of fly ash based geopolymer for rigid pavement applications.

7.
Materials (Basel) ; 14(11)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073169

RESUMO

This study intended to address the problem of damaged (collapsed, cracked and decreased soil strength) road pavement structure built on clay soil due to clay soil properties such as low shear strength, high soil compressibility, low soil permeability, low soil strength, and high soil plasticity. Previous research reported that ground granulated blast slag (GGBS) and fly ash can be used for clay soil stabilizations, but the results of past research indicate that the road pavement construction standards remained unfulfilled, especially in terms of clay's subgrade soil. Due to this reason, this study is carried out to further investigate soil stabilization using GGBS and fly ash-based geopolymer processes. This study investigates the effects of GGBS and ratios of fly ash (solid) to alkaline activator (liquid) of 1:1, 1.5:1, 2:1, 2.5:1, and 3:1, cured for 1 and 7 days. The molarity of sodium hydroxide (NaOH) and the ratio of sodium silicate (Na2SiO3) to sodium hydroxide (NaOH) was fixed at 10 molar and 2.0 weight ratio. The mechanical properties of the soil stabilization based geopolymer process were tested using an unconfined compression test, while the characterization of soil stabilization was investigated using the plastic limit test, liquid limit test, scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The results showed that the highest strength obtained was 3.15 MPA with a GGBS to alkaline activator ratio of 1.5 and Na2SiO3 to NaOH ratio of 2.0 at 7 days curing time. These findings are useful in enhancing knowledge in the field of soil stabilization-based geopolymer, especially for applications in pavement construction. In addition, it can be used as a reference for academicians, civil engineers, and geotechnical engineers.

8.
Materials (Basel) ; 14(5)2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33652863

RESUMO

The demand for durable, resistant, and high-strength structural material has led to the use of fibers as reinforcing elements. This paper presents an investigation into the inclusion of chopped steel wool fibers (CSWFs) in cement to form a high-flexural strength cementitious composite matrix (CCM). CSWFs were used as the primary reinforcement in CCM at increments of 0.5 wt%, from 0.5-6 wt%, with ratios of cement to sand of 1:1.5 and water to cement of 0.45. The inclusion of CSWFs resulted in an excellent optimization of the physicomechanical properties of the CCM, such as its density (2.302 g/cm3), compressive strength (61.452 MPa), and maximum flexural strength (10.64 MPa), all of which exceeded the performances of other reinforcement elements reported in the literature.

9.
Mini Rev Med Chem ; 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32767940

RESUMO

The article has been withdrawn at the request of the authors and editor of the journal Mini-Reviews in Medicinal Chemistry due to incoherent content. Bentham Science apologizes to the readers of the journal for any inconvenience this may have caused. The Bentham Editorial Policy on Article Withdrawal can be found at https://benthamscience.com/editorialpolicies-main.php Bentham Science Disclaimer: It is a condition of publication that manuscripts submitted to this journal have not been published and will not be simultaneously submitted or published elsewhere. Furthermore, any data, illustration, structure or table that has been published elsewhere must be reported, and copyright permission for reproduction must be obtained. Plagiarism is strictly forbidden, and by submitting the article for publication the authors agree that the publishers have the legal right to take appropriate action against the authors, if plagiarism or fabricated information is discovered. By submitting a manuscript, the authors agree that the copyright of their article is transferred to the publishers if and when the article is accepted for publication.

10.
Materials (Basel) ; 14(1)2020 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-33374466

RESUMO

In recent years, research and development of geopolymers has gained significant interest in the fields of repairs and restoration. This paper investigates the application of a geopolymer as a repair material by implementation of high-calcium fly ash (FA) as a main precursor, activated by a sodium hydroxide and sodium silicate solution. Three methods of concrete substrate surface preparation were cast and patched: as-cast against ordinary Portland cement concrete (OPCC), with drilled holes, wire-brushed, and left as-cast against the OPCC grade 30. This study indicated that FA-based geopolymer repair materials (GRMs) possessed very high bonding strength at early stages and that the behavior was not affected significantly by high surface treatment roughness. In addition, the investigations using scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) spectroscopy have revealed that the geopolymer repair material became chemically bonded to the OPC concrete substrate, due to the formation of a C-A-S-H gel. Fundamentally, the geopolymer network is composed of tetrahedral anions (SiO4)4- and (AlO4)5- sharing the oxygen, which requires positive ions such as Na+, K+, Li+, Ca2+, Na+, Ba2+, NH4+, and H3O+. The availability of calcium hydroxide (Ca(OH)2) at the surface of the OPCC substrate, which was rich in calcium ions (Ca2+), reacted with the geopolymer; this compensated the electron vacancies of the framework cavities at the bonding zone between the GRM and the OPCC substrate.

11.
World Neurosurg ; 117: e612-e630, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29936209

RESUMO

BACKGROUND: Craniovertebral junction diseases, although considered rare, are common in northern parts of India. This study was conducted to evaluate the clinico-radiologic and surgical outcome of patients with a minimum follow-up of 1 year. Our study also compared bony fusion among various techniques of posterior fusion. METHODS: This retrospective study was performed with 38 patients who met the inclusion criteria for analysis. These patients were contacted by telephone and letters, and their clinical examination and radiologic investigations were performed at a follow-up visit. The preoperative, postoperative, and follow-up clinical evaluations of the patients were done using the Nurick grading system. RESULTS: The age range was 4-60 years with an average of 20.5 years. There were 31 male and 7 female patients, with a male:female ratio of 4.43:1. There were 13 cases of fixed atlantoaxial dislocation (AAD), 17 cases of mobile AAD, 6 cases of traumatic AAD, and 2 cases of postinfective AAD. The majority of these patients (n = 29; 76.31%) had neck pain and cerebellovestibular disturbances (n = 27; 71.1%). Sphincter disturbances were observed in 9 patients. An increase in craniovertebral angle was observed in postoperative period in all patients. Initially, 84% of the patients had a poor Nurick grade; this was reduced to 28% after the surgical intervention. One hundred percent bony fusion was attained in patients who underwent rigid fixation technique, and 80% was attained using a semirigid fixation technique. CONCLUSIONS: The key to successful management of craniovertebral junction disease is individualized selection of judicious surgical intervention from various available techniques.


Assuntos
Articulação Atlantoaxial/diagnóstico por imagem , Articulação Atlantoaxial/cirurgia , Luxações Articulares/diagnóstico por imagem , Luxações Articulares/cirurgia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença , Fusão Vertebral , Centros de Atenção Terciária , Resultado do Tratamento , Adulto Jovem
12.
BMJ Case Rep ; 20162016 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-27469385

RESUMO

An 8-year-old boy presented with a 1-year history of low backache, followed by paraparesis and urinary incontinence. MRI of the thoracic spine revealed an intramedullary, intensely contrast-enhancing lesion extending from T11 to L1 vertebral level, consistent with astrocytoma, ependymoma or haemangioblastoma. A diagnosis of intramedullary chordoma was made on tissue biopsy and immunohistochemical study. This is the second report of an intramedullary chordoma without bone involvement in English literature. After 6 months of follow-up, patient showed good clinical outcome in terms of improvement in power in lower limbs and backache.


Assuntos
Cordoma/diagnóstico por imagem , Neoplasias da Medula Espinal/diagnóstico por imagem , Criança , Cordoma/patologia , Cordoma/cirurgia , Meios de Contraste , Diagnóstico Diferencial , Humanos , Aumento da Imagem , Laminectomia , Imageamento por Ressonância Magnética , Masculino , Medula Espinal/diagnóstico por imagem , Medula Espinal/patologia , Medula Espinal/cirurgia , Neoplasias da Medula Espinal/patologia , Neoplasias da Medula Espinal/cirurgia , Vértebras Torácicas/diagnóstico por imagem
13.
Meta Gene ; 7: 70-5, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26862483

RESUMO

Here, we sequenced and functionally annotated the long reads (1-2 kb) cDNAs library of an infratentorial ependymoma tumor tissue on PacBio RSII by Iso-Seq protocol using SMRT technology. 577 MB, data was generated from the brain tissues of ependymoma tumor patient, producing 1,19,313 high-quality reads assembled into 19,878 contigs using Celera assembler followed by Quiver pipelines, which produced 2952 unique protein accessions in the nr protein database and 307 KEGG pathways. Additionally, when we compared GO terms of second and third level with alternative splicing data obtained through HTA Array2.0. We identified four and twelve transcript cluster IDs in Level-2 and Level-3 scores respectively with alternative splicing index predicting mainly the major pathways of hallmarks of cancer. Out of these transcript cluster IDs only transcript cluster IDs of gene PNMT, SNN and LAMB1 showed Reads Per Kilobase of exon model per Million mapped reads (RPKM) values at gene-level expression (GE) and transcript-level (TE) track. Most importantly, brain-specific genes--PNMT, SNN and LAMB1 show their involvement in Ependymoma.

14.
J Biomol Struct Dyn ; 33(3): 625-38, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24650131

RESUMO

Cefotaxime hydrolyzing ß-lactamase-15 (CTX-M-15) is encoded by blaCTX-M-15 gene present on plasmid of various Gram-negative bacteria, such as E. coli, E. cloacae, K. pneumoniae, etc. The widespread dissemination of CTX-M-15 harboring bacteria in hospital as well as community settings is a universal threat as they are resistant to various clinically significant antibiotics. In order to gain an insight into the folding mechanism of CTX-M-15, we carried out pH-induced denaturation study by monitoring Trp fluorescence, far-UV circular dichroism (CD), and ANS fluorescence. We found that the pH-induced denaturation of CTX-M-15 was a three-step process with the accumulation of two stable folding intermediates (XI at pH 2.5 and XII at pH 1.5) in the folding pathway. The intermediates were further characterized by far-UV and near-UV CD analysis, Trp fluorescence, ANS fluorescence, three-dimensional fluorescence, acrylamide quenching, dynamic light scattering, and thermal denaturation studies. We found that XI state lacked tertiary structure but retained most of the secondary structure, its Trp residues were partially exposed to the solvent and its hydrophobic patches were highly accessible to ANS. On the other hand, a complete disruption of tertiary structure along with more than 50% loss in secondary structure was observed in XII state. We conclude that the XI state of CTX-M-15 at pH 2.5 had all the characteristics of a molten globule (MG) state, while its XII state at pH 1.5 was more similar to pre-molten globule (PMG) state. ANS fluorescence also showed that the binding of ANS in XII state was lower than that in the XI state. We propose that the accumulation of MG- and PMG-states was due to separation (at pH 2.5) and then unfolding (at pH 1.5) of the αßα-fold of CTX-M-15, respectively.


Assuntos
Proteínas de Bactérias/química , beta-Lactamases/química , Cefotaxima , Enterobacter cloacae/enzimologia , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Desnaturação Proteica , Estrutura Secundária de Proteína , Espectrometria de Fluorescência , Termodinâmica
15.
J Med Case Rep ; 5: 370, 2011 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-21838905

RESUMO

INTRODUCTION: Teratoma is a tumor that usually arises from one or more germ layers. They are most commonly found in the sacrococcygeal region and have a female preponderance. We present a very rare case of a boy with a benign cystic teratoma in the lumbosacral region. CASE PRESENTATION: A 16-year-old Indian boy presented to our hospital with a history of a lump in the lower back region since birth. Initially, it was small, but its size increased gradually over time to a size of 15 cm × 15 cm at presentation. There were no other associated abnormalities. Investigations revealed the lump to be a benign cystic teratoma. The patient underwent surgery, and the whole tumor, from its base to the vertebrae, was excised. Bisection of the tumor revealed that it contained hair and pultaceous material consistent with a teratoma, which was later confirmed by histopathologic examination. CONCLUSION: Benign cystic teratomas should be diagnosed and managed aggressively because they generally have a greater tendency to progress toward malignancy. After extensively searching the case report database, we arrived at the conclusion that this was a rare case of a benign cystic teratoma in the lumbosacral region in a boy.

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