Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 30
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
3.
Indian J Surg Oncol ; 15(1): 181-184, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38511032

RESUMO

Epithelioid hemangioma also known as angio-lymphoid hyperplasia with eosinophilia is a rare benign vascular neoplasm of unknown etiology. It very rarely involves the nasal cavity. It always poses a diagnostic challenge for clinicians and is usually misdiagnosed as Kimura's, IgG4-related disease, or malignant vascular tumors. The present case report describes an extremely rare presentation of epithelioid hemangioma inside the left nasal cavity causing complete obstruction and nasal septal deviation towards the right side in a young male. Hematoxylin and eosin-stained sections depicted a lobular proliferation of small capillary-sized vessels lined by plump epithelioid endothelial cells surrounding central vessels and scattered around them. These cells had abundant eosinophilic to amphophilic cytoplasm and enlarged nuclei with fine chromatin and central nucleoli. On immunohistochemistry, CD34 and CD31 highlighted the vascular proliferation and epithelioid endothelial cells. Erythroblast transformation-specific (ETS)-related gene (ERG) showed strong nuclear positivity in neoplastic plump epithelioid endothelial cells. EH is a benign vascular proliferation, but a high chance of recurrence is seen if complete resection is not done. As a result, the treatment of choice is complete surgical excision with clear margins. The case highlights a non-conventional presentation of epithelioid hemangioma and the importance of histomorphological features in diagnosing this entity.

4.
J Mycol Med ; 34(2): 101467, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38432117

RESUMO

A 3-year-old boy presented with acute headache, vomiting and right focal clonic seizures without history of fever, joint pain or altered sensorium. Neuroimaging showed multifocal contrast enhancing lesions with significant perilesional edema. CECT chest and abdomen showed multiple variable sized nodules in the lungs and hypodense lesion in liver with mesenteric lymphadenopathy. There was persistent eosinophilia with maximum upto 35 %. Liver biopsy and brain biopsy revealed Cladophialophora bantiana. He was treated with IV liposomal amphotericin and voriconazole for 6 weeks with repeat neuroimaging showing more than 50 % resolution of the intracranial lesions. He was transitioned to oral combination of flucytosine and voriconazole. At 14 months follow-up, he remained symptom free with complete radiological resolution of the lesions and no eosinophilia. High suspicion, an aggressive approach in obtaining microbiological diagnosis and timely combination antifungal therapy may give satisfactory outcome without surgery.

5.
Neuropathology ; 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409890

RESUMO

Astroblastoma is an uncommon circumscribed glial tumor mostly involving the cerebral hemisphere. The characteristic molecular alteration is meningioma (disrupted in balanced translocation) 1 (MN1) rearrangement. No definite World Health Organization grade has been assigned as both low- and high-grade tumors are known to occur. Tumors in the spine are extremely rare; to date only three cases have been reported in the literature. A vigilant microscopy and ancillary testing aid in diagnosis when the tumors present in unusual locations, as in our case. The prompt differentiation of this tumor from its mimickers is a mandate as modalities of management are different and not clearly established.

6.
Neuropathology ; 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38410881

RESUMO

Adamantinomatous craniopharyngioma is a grade 1 tumor that arises in a sellar/suprasellar location. Despite being a grade 1 tumor, there is high recurrence and endocrinal insufficiency. Malignancy arising in craniopharyngioma is extremely rare, has a dismal prognosis, and is currently not included as a separate entity in the World Health Organization Classification of Central Nervous System 5th edition. Here we describe a case of adamantinomatous craniopharyngioma and its malignant counterpart. The malignant part had unique histomorphology and basaloid cells with pseudoglandular architecture and a myxoid background. It bore a striking resemblance to adenoid cystic carcinoma. Both the benign and malignant counterparts were beta-catenin and SOX-2 positive, providing proof of the malignant part arising from the benign part. Tumors like squamous cell carcinoma and odontogenic ghost cell carcinoma have been described in cranipharyngioma. This case study is the first to describe this unique morphology of adenoid cystic carcinoma-like features. The possibility of adenoid cystic carcinoma was excluded by immunohistochemistry.

7.
World Neurosurg ; 184: e486-e493, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38307196

RESUMO

BACKGROUND: Papillary tumors of pineal region (PTPR) comprise a very rare subset of pineal region tumors that have been recently described. Literature on the management and outcome of PTPR is scarce owing to the rarity of these tumors. To address this lacuna, we analyzed our experience in management of PTPR. METHODS: We retrospectively analyzed the outcome of 11 patients with histopathologically proven PTPR who underwent surgical excision at our center. RESULTS: Mean patient age was 33.3 years (range, 12-45 years), and male-to-female ratio was 1.75:1. Headache was the most common presentation followed by visual disturbances, altered sensorium, Perinaud syndrome, and seizures. Cerebrospinal fluid diversion was required in 6 patients. Krause approach was the most common approach used for tumor excision (9/11 cases). There was no perioperative mortality. Two patients were lost to follow-up. In the remaining 9 patients, the average follow-up period was 45 months (range, 12-79 months). On first postoperative magnetic resonance imaging, 8 patients showed no evidence of residual tumor (gross total resection), while 1 patient had small residual tumor (near-total resection) that remained stable during follow-up. Four patients underwent adjuvant chemoradiotherapy. None of the patients developed recurrence during follow-up. CONCLUSIONS: PTPR are a rare subgroup of pineal region tumors with distinct cells of origin but presentation similar to other pineal region tumors. Surgical resection constitutes the mainstay of management, and the extent of resection appears to be the most important determinant of prognosis. The role of adjuvant therapy still needs to be determined.


Assuntos
Neoplasias Encefálicas , Glândula Pineal , Pinealoma , Humanos , Masculino , Feminino , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasia Residual/patologia , Glândula Pineal/diagnóstico por imagem , Glândula Pineal/cirurgia , Glândula Pineal/patologia , Pinealoma/cirurgia , Pinealoma/patologia , Neoplasias Encefálicas/patologia
8.
Materials (Basel) ; 17(2)2024 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-38276452

RESUMO

In this study, alder, spruce, and beech woods were used for homogeneous symmetric, inhomogeneous symmetric (combined) and inhomogeneous non-symmetric glued laminated timber (glulam) beams glued with resorcinol phenol formaldehyde (RPF) adhesive. The aim of this paper is to determine and compare the modulus of elasticity of glulam beams using three methods, i.e., analytical calculation, numerical model (FEM) and experimental testing. As an additional characteristic, the bending strength (MOR) of the beams was determined during experimental testing. Analytical calculation was used to calculate the modulus of elasticity (MOE) of glued laminated timber based on the knowledge of the modulus of elasticity of solid wood and to estimate the location of the neutral axis during bending. According to calculations, for symmetrical combinations, the deviation from the real neutral axis does not exceed 5%. In the case of the modulus of elasticity, the deviation is an average of 4.1% from that of the actual measured beams. The numerical model includes finite element modelling, where the deflection of the modelled beams can be calculated with a deviation of up to 10%. The last method was experimental testing of glued beams using four-point bending, in which, among homogeneous beams, beech glulam beams achieved the highest MOE and MOR, while alder glulam beams achieved the lowest. The combination of wood species resulted in an increase in both MOE and MOR compared to homogeneous spruce and alder beams.

9.
Environ Health Insights ; 17: 11786302231201259, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37808962

RESUMO

Along with expanding urbanization and industrialization, environmental pollution which negatively affects the surroundings, has been rising quickly. As a result, induces heavy metal contamination which poses a serious threat to living organisms of aquatic and soil ecosystems. Therefore, they are a need to ameliorate the effects cost by cost pollution on the environment. In this review, we explore methods employed to mitigate the effects caused by heavy metals on the environment. Many techniques employed to manage environmental pollution are tedious and very costly, necessitating the use of alternative management strategies to resolve this challenge. In this concept, bioremediation is viewed as a future technique, due to its environmental friendliness and cost-effective measures aligned with sustainable or climate-smart agriculture to manage contaminants in the environment. The technique involves the use of living entities such as bacteria, fungi, and plants to deteriorate toxic substances from the rhizosphere. Currently, bioremediation is thought to be the most practical, dependable, environmentally benign, and long-lasting solution. Although bioremediation involves different techniques, they are still a need to find the most efficient method for removing toxic substances from the environment. This review focuses on the origins of heavy metal pollution, delves into cost-effective and green technological approaches for eliminating heavy metal pollutants from the environment, and discusses the impact of these pollutants on human health.

10.
J R Coll Physicians Edinb ; 53(1): 23-26, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36680356

RESUMO

Acanthamoeba is a rare cause of granulomatous amoebic encephalitis (GAE) associated with high mortality. There have been few case reports of Acanthamoeba meningoencephalitis worldwide. Hemophagocytic lymphohistiocytosis (HLH) is a severe hyperinflammatory condition caused by abnormally active macrophages and cytotoxic T lymphocytes; its secondary form is due to infections or malignancies. However, HLH is rather an unknown complication of GAE. We describe an unusual and previously unreported case of Acanthamoeba meningoencephalitis in a young immunocompetent female culminating in secondary HLH.


Assuntos
Infecções Protozoárias do Sistema Nervoso Central , Linfo-Histiocitose Hemofagocítica , Humanos , Feminino , Linfo-Histiocitose Hemofagocítica/complicações , Linfo-Histiocitose Hemofagocítica/diagnóstico , Infecções Protozoárias do Sistema Nervoso Central/complicações , Infecções Protozoárias do Sistema Nervoso Central/diagnóstico , Granuloma/complicações
12.
Plants (Basel) ; 13(1)2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38202406

RESUMO

The global industrial revolution has led to a substantial rise in heavy metal levels in the environment, posing a serious threat to nature. Plants synthesize phenolic compounds under stressful conditions, which serve as protective agents against oxidative stress. Basilicum polystachyon (L.) Moench is an herbaceous plant of the Lamiaceae family. Some species within this family are recognized for their capacity to remediate sites contaminated with heavy metals. In this study, the effects of mercury (II) chloride and lead (II) nitrate on the in vitro propagation of B. polystachyon were investigated. Shoot tips from in vitro plantlets were cultured in Murashige and Skoog's (MS) media with heavy metals ranging from 1 to 200 µM to induce abiotic stress and enhance the accumulation of phenolic compounds. After three weeks, MS medium with 1 µM of lead (II) supported the highest shoot multiplication, and the maximum number of roots per explant was found in 100 µM of lead (II), whereas a higher concentration of heavy metals inhibited shoot multiplication and root development. The plantlets were hardened in a greenhouse with a 96% field survival rate. Flame atomic absorption spectroscopy (FAAS) was used to detect heavy metal contents in plant biomass. At both 200 µM and 50 µM concentrations, the greatest accumulation of mercury (II) was observed in the roots (16.94 ± 0.44 µg/g) and shoots (17.71 ± 0.66 µg/g), respectively. Similarly, lead (II) showed the highest accumulation in roots (17.10 ± 0.54 µg/g) and shoots (7.78 ± 0.26 µg/g) at 200 µM and 50 µM exposures, respectively. Reverse-phase high-performance liquid chromatography (RP-HPLC) identified and quantified various phenolic compounds in B. polystachyon leaves, including gallic acid, caffeic acid, vanillic acid, p-coumaric acid, ellagic acid, rosmarinic acid, and trans-cinnamic acid. These compounds were found in different forms, such as free, esterified, and glycosylated. Mercury (II)-exposed plants exhibited elevated levels of vanillic acid (1959.1 ± 3.66 µg/g DW), ellagic acid (213.55 ± 2.11 µg/g DW), and rosmarinic acid (187.72 ± 1.22 µg/g DW). Conversely, lead (II)-exposed plants accumulated higher levels of caffeic acid (42.53±0.61 µg/g DW) and p-coumaric acid (8.04 ± 0.31 µg/g DW). Trans-cinnamic acid was the predominant phenolic compound in control plants, with a concentration of 207.74 ± 1.45 µg/g DW. These results suggest that sublethal doses of heavy metals can act as abiotic elicitors, enhancing the production of phenolic compounds in B. polystachyon. The present work has the potential to open up new commercial opportunities in the pharmaceutical industry.

13.
Aging Med (Milton) ; 5(3): 237-240, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36247336

RESUMO

Limb-girdle muscular dystrophy is a genetic disorder usually presenting in younger age patients. This case report presents a case of late-onset limb-girdle muscular dystrophy type R1 (Calpainopathy) in a 65 year old patient.

14.
ACS Appl Mater Interfaces ; 14(38): 43666-43680, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36107717

RESUMO

This paper implements molecular dynamics (MD) simulation using reactive force field (ReaxFF) to evaluate the atomistic origin of the interfacial behavior in the overmolded hybrid unidirectional continuous carbon fiber low-melt PAEK (CFR-LMPAEK)-short carbon fiber reinforced PEEK (SFR-PEEK) polymer composites. From the MD simulation, it was observed that the interfacial properties improve with increasing maximum processing temperature and injection pressure although such an improving trajectory gets saturated beyond specific limits. The interfacial strength and fracture response of the hybrid polymer system at the interface are also evaluated. The mechanical responses obtained from MD simulation are used as adhesive properties in the macroscale finite element analysis (FEA)-based single lap joint (SLJ) model where the interfacial behavior between the adherends (CFR-LMPAEK and SFR-PEEK) is implemented using cohesive zone model (CZM). The simulated FE results show a good correlation with the SLJ experimental data. Thus, by linking the interfacial properties at the molecular scale to the performance of the interfacial bond at the macroscale, the comprehensive approach presented here opens up various efficient avenues toward atomistically engineered performance tuning in hybrid overmolded fiber-reinforced polymer composites to meet desired large-scale performance needs.

15.
Sci Rep ; 12(1): 1683, 2022 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-35102225

RESUMO

Thunbergia coccinea Wall. ex D. Don being a rare, ornamental and medicinal plant of India, is needed to propagate for conserving the germplasm and analyzing its phytochemical compounds in the future. A reliable protocol for direct in vitro propagation using nodal shoot meristem of T. coccinea as explant was standardized. The highest number of shoots per explant (22.17 ± 0.54) with maximum shoot length (2.36 ± 0.28) in cm was obtained in Murashige and Skoog (MS) medium supplemented with 9.70 µM of 6-furfurylaminopurine (Kinetin) and 0.053 µM of α-naphthaleneacetic acid (NAA) combination, among all the different plant growth regulators (PGR's) and concentrations tested. The aforesaid PGR's combination was optimum for axillary shoot bud induction and multiplication in T. coccinea. The best rooting was observed on the half-strength MS medium fortified with 2.68 µM NAA with the highest number of roots per shoot (3.75 ± 0.12) and maximum length (5.22 ± 0.32) in cm. All the in vitro raised plantlets were acclimatized in sterile sand and soil mixture (1:1) with a survival rate of 70% on earthen pots under greenhouse conditions. PCR-based RAPD (Random Amplified Polymorphic DNA) and ISSR (Inter-Simple Sequence Repeat) molecular markers were employed to determine the genetic homogeneity amongst the plantlets. Twelve (12) RAPD and nine (9) ISSR primers developed a total of 104 and 91 scorable bands, respectively. The band profiles of micropropagated plantlets were monomorphic to the mother, donor in vivo plant, and similarity values varied from 0.9542-1.000. The dendrogram generated through UPGMA (unweighted pair group method with arithmetic mean) showed 99% similarities amongst all tested plants confirming the genetic uniformity of in vitro raised plants.


Assuntos
Acanthaceae/genética , DNA de Plantas/genética , Genes de Plantas , Genoma de Planta , Meristema/genética , Repetições de Microssatélites , Técnica de Amplificação ao Acaso de DNA Polimórfico , Acanthaceae/efeitos dos fármacos , Acanthaceae/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Marcadores Genéticos , Instabilidade Genômica , Genótipo , Cinetina/farmacologia , Meristema/efeitos dos fármacos , Meristema/crescimento & desenvolvimento , Ácidos Naftalenoacéticos/farmacologia , Reguladores de Crescimento de Plantas/farmacologia
16.
Materials (Basel) ; 14(16)2021 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-34442958

RESUMO

This paper investigates the dynamic compressive behavior of wollastonite fiber-reinforced cementitious mortars using multiscale numerical simulations. The rate dependent behavior of the multiphase heterogeneous systems is captured in a multiscale framework that implements continuum damage towards effective property prediction. The influence of wollastonite fiber content (% by mass) as cement replacement on the dynamic compressive strength and energy absorption capacity is thereafter elucidated. An average compressive strength gain of 40% is obtained for mortars with 10% wollastonite fiber content as cement replacement, as compared to the control mortar at a strain rate of 200/s. The rate dependent constitutive responses enable the computation of energy absorption, which serves as a comparative measure for elucidating the material resistance to impact loads. Approximately a 45% increase in the dynamic energy absorption capacity is observed for the mixture containing 10% wollastonite fibers, as compared to the control case. Overall, the study establishes wollastonite fibers as a sustainable and dynamic performance-enhanced alternative for partial cement replacement. Moreover, the multiscale numerical simulation approach for performance prediction can provide an efficient means for the materials designers and engineers to optimize the size and dosage of wollastonite fibers for desired mechanical performance under dynamic loading conditions.

17.
Curr Microbiol ; 78(8): 2961-2969, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34081183

RESUMO

In the present study, a plant growth-promoting bacterium isolated from contaminated in vitro-grown Basilicum polystachyon (L.) Moench, an herbaceous plant, was studied and identified as Acinetobacter strain SuKIC24 based on the 16S rRNA gene sequence analysis. The results revealed that the identified strain exhibited a strong ability to solubilize the phosphate with phosphate solubilization index of 4.0 and produced 387 µg/ml of soluble phosphate in Pikovskaya media after 7 days of incubation, whereas zinc solubilization efficacy was determined to be 175%. Reversed-phase high-performance liquid chromatography (RP-HPLC) analysis revealed that the bacterium strain produced 77.36 µg/ml of indole-3-acetic acid. Plant inoculated with the bacterium strain was found to demonstrate a significant increase in height of B. polystachyon as compared to the control plant. The present findings indicated that the identified bacterium strain might act as plant growth-promoting bacterium (PGPB).


Assuntos
Acinetobacter , Acinetobacter/genética , Bactérias , Desenvolvimento Vegetal , RNA Ribossômico 16S/genética , Microbiologia do Solo
18.
Sci Rep ; 10(1): 21336, 2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-33288786

RESUMO

Prediction of material behavior using machine learning (ML) requires consistent, accurate, and, representative large data for training. However, such consistent and reliable experimental datasets are not always available for materials. To address this challenge, we synergistically integrate ML with high-throughput reactive molecular dynamics (MD) simulations to elucidate the constitutive relationship of calcium-silicate-hydrate (C-S-H) gel-the primary binding phase in concrete formed via the hydration of ordinary portland cement. Specifically, a highly consistent dataset on the nine elastic constants of more than 300 compositions of C-S-H gel is developed using high-throughput reactive simulations. From a comparative analysis of various ML algorithms including neural networks (NN) and Gaussian process (GP), we observe that NN provides excellent predictions. To interpret the predicted results from NN, we employ SHapley Additive exPlanations (SHAP), which reveals that the influence of silicate network on all the elastic constants of C-S-H is significantly higher than that of water and CaO content. Additionally, the water content is found to have a more prominent influence on the shear components than the normal components along the direction of the interlayer spaces within C-S-H. This result suggests that the in-plane elastic response is controlled by water molecules whereas the transverse response is mainly governed by the silicate network. Overall, by seamlessly integrating MD simulations with ML, this paper can be used as a starting point toward accelerated optimization of C-S-H nanostructures to design efficient cementitious binders with targeted properties.

19.
Phys Chem Chem Phys ; 22(41): 23707-23724, 2020 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-33057524

RESUMO

This paper presents the dynamics of confined water and its interplay with alkali cations in disordered sodium aluminosilicate hydrate (N-A-S-H) gel using reactive force field molecular dynamics. N-A-S-H gel is the primary binding phase in geopolymers formed via alkaline activation of fly ash. Despite attractive mechanical properties, geopolymers suffer from durability issues, particularly the alkali leaching problem which has motivated this study. Here, the dynamics of confined water and the mobility of alkali cations in N-A-S-H is evaluated by obtaining the evolution of mean squared displacements and Van Hove correlation function. To evaluate the influence of the composition of N-A-S-H on the water dynamics and diffusion of alkali cations, atomistic structures of N-A-S-H with Si/Al ratio ranging from 1 to 3 are constructed. It is observed that the diffusion of confined water and sodium is significantly influenced by the Si/Al ratio. The confined water molecules in N-A-S-H exhibit a multistage dynamic behavior where they can be classified as mobile and immobile water molecules. While the mobility of water molecules gets progressively restricted with an increase in Si/Al ratio, the diffusion coefficient of sodium also decreases as the Si/Al ratio increases. The diffusion coefficient of water molecules in the N-A-S-H structure exhibits a lower value than those of the calcium-silicate-hydrate (C-S-H) structure. This is mainly due to the random disordered structure of N-A-S-H as compared to the layered C-S-H structure. To further evaluate the influence of water content in N-A-S-H, atomistic structures of N-A-S-H with water contents ranging from 5-20% are constructed. Qn distribution of the structures indicates significant depolymerization of N-A-S-H structure with increasing water content. Increased conversion of Si-O-Na network to Si-O-H and Na-OH components with an increase in water content helps explain the alkali-leaching issue in fly ash-based geopolymers observed macroscopically. Overall, the results in this study can be used as a starting point towards multiscale simulation-based design and development of durable geopolymers.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...