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1.
World Neurosurg ; 184: e743-e753, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38342171

RESUMO

BACKGROUND: Papilledema's association with hydrocephalus (HCP)-linked larger vestibular schwannoma (VS) is established but cases lacking concurrent HCP require further investigation. METHODS: This retrospective comparative observational study, conducted from July 2018 to July 2023, examined 120 VS patients undergoing surgery. Patients were categorized into Group 1 (papilledema without HCP) and Group 2 (no papilledema or HCP), with comprehensive data analyzed. RESULTS: In this study, Group 1 (14 patients with papilledema) and Group 2 (106 patients without papilledema or HCP) were compared. Group 1 was younger (mean age 27.21 ± 11.73 years) than Group 2 (mean age 54.66 ± 11.44 years). Both groups had similar symptom durations and tumor detection times. Group 1 had increased vascularity (P = 0.001), elevated cisterna magna protein levels (P = 0.001), and a higher incidence of neurofibromatosis 2 (P = 0.003). They also experienced longer surgeries (P = 0.001) and more blood loss (P = 0.001), leading to extended postoperative complications. Group 2 showed improved postsurgery visual outcomes (P = 0.001), better Glasgow Outcome Scores (P = 0.001), enhanced facial nerve preservation (P = 0.002), and improved hearing on follow-up (P = 0.003). Logistic regression analysis highlighted prolonged surgery duration (P = 0.057) and papilledema (P = 0.0001) as significant factors influencing visual improvement. CONCLUSIONS: Patients with VS require preoperative fundoscopy evaluation due to potential visual loss and papilledema, even without HCP. Early treatment initiation enhances visual and hearing outcomes. Meticulous surgery is vital given the lesion's hypervascular nature and adherence to surrounding structures. Preoperative embolization may aid in preserving neurovascular structures. In developing countries with higher blindness rates, judicious noncontrast computed tomography brain evaluation is crucial for timely detection and treatment initiation of lesions like VS.


Assuntos
Hidrocefalia , Neuroma Acústico , Papiledema , Humanos , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Neuroma Acústico/complicações , Neuroma Acústico/diagnóstico por imagem , Neuroma Acústico/cirurgia , Papiledema/diagnóstico por imagem , Papiledema/etiologia , Estudos Retrospectivos , Hidrocefalia/etiologia , Hidrocefalia/cirurgia , Hidrocefalia/diagnóstico , Cegueira , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Progressão da Doença , Resultado do Tratamento
2.
Cancers (Basel) ; 15(18)2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37760422

RESUMO

PURPOSE: The isocitrate dehydrogenase (IDH) mutation has become one of the most important prognostic biomarkers in glioma management, indicating better treatment response and prognosis. IDH mutations confer neomorphic activity leading to the conversion of alpha-ketoglutarate (α-KG) to 2-hydroxyglutarate (2HG). The purpose of this study was to investigate the clinical potential of proton MR spectroscopy (1H-MRS) in identifying IDH-mutant gliomas by detecting characteristic resonances of 2HG and its complex interplay with other clinically relevant metabolites. MATERIALS AND METHODS: Thirty-two patients with suspected infiltrative glioma underwent a single-voxel (SVS, n = 17) and/or single-slice-multivoxel (1H-MRSI, n = 15) proton MR spectroscopy (1H-MRS) sequence with an optimized echo-time (97 ms) on 3T-MRI. Spectroscopy data were analyzed using the linear combination (LC) model. Cramér-Rao lower bound (CRLB) values of <40% were considered acceptable for detecting 2HG and <20% for other metabolites. Immunohistochemical analyses for determining IDH mutational status were subsequently performed from resected tumor specimens and findings were compared with the results from spectral data. Mann-Whitney and chi-squared tests were performed to ascertain differences in metabolite levels between IDH-mutant and IDH-wild-type gliomas. Receiver operating characteristic (ROC) curve analyses were also performed. RESULTS: Data from eight cases were excluded due to poor spectral quality or non-tumor-related etiology, and final data analyses were performed from 24 cases. Of these cases, 9/12 (75%) were correctly identified as IDH-mutant or IDH-wildtype gliomas through SVS and 10/12 (83%) through 1H-MRSI with an overall concordance rate of 79% (19/24). The sensitivity, specificity, positive predictive value, and negative predictive value were 80%, 77%, 86%, and 70%, respectively. The metabolite 2HG was found to be significant in predicting IDH-mutant gliomas through the chi-squared test (p < 0.01). The IDH-mutant gliomas also had a significantly higher NAA/Cr ratio (1.20 ± 0.09 vs. 0.75 ± 0.12 p = 0.016) and lower Glx/Cr ratio (0.86 ± 0.078 vs. 1.88 ± 0.66; p = 0.029) than those with IDH wild-type gliomas. The areas under the ROC curves for NAA/Cr and Glx/Cr were 0.808 and 0.786, respectively. CONCLUSIONS: Noninvasive optimized 1H-MRS may be useful in predicting IDH mutational status and 2HG may serve as a valuable diagnostic and prognostic biomarker in patients with gliomas.

3.
3 Biotech ; 13(5): 123, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37033385

RESUMO

Potato cyst nematodes, Globodera pallida and G. rostochiensis, are economically important and difficult to manage pests of the potato crop. The cyst of both the species looks similar and it is difficult to differentiate once it turns brown upon maturity. Early detection of the PCN at the species level is crucial to avoid its further spread and for adopting the appropriate management strategies. Therefore, in the present study, highly specific and sensitive loop-mediated isothermal amplification (LAMP) assay was developed to amplify mitochondrial-Sequence Characterized Amplified Region (SCAR) sequence of potato cyst nematode, G. pallida. The LAMP assay was completed within a shorter incubation period of 60 min at 60 °C followed by the reaction termination at 80 °C for 5 min. The developed LAMP assay exhibited high specificity for G. pallida and did not detect any other species including its sibling species, G. rostochiensis. In sensitivity tests, the assay detected G. pallida at 1000 times less DNA concentration (10 fg/µl) as compared to conventional PCR (10 pg/µl). In addition to this, the developed LAMP assay was tested for the detection of G. pallida directly from the soil samples, and even a single cyst mixed with soil was successfully detected by the developed assay. Moreover, the utility of low-cost instruments like hot water bath was also demonstrated for the detection of G. pallida from the soil. The developed LAMP is a rapid, highly specific, sensitive, and cost-effective technique for the species-specific detection of G. pallida. The developed assay will facilitate the rapid detection of G. pallida at quarantine stations as well as from the fields which will help to stop its further spread in new areas and also to devise effective management strategies for sustainable potato production. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03542-x.

4.
Front Oncol ; 13: 1304106, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38273844

RESUMO

Introduction: Head and neck squamous cell carcinoma (HNSCC) constitutes a heterogeneous group of cancers. Human papilloma virus (HPV) is associated with a subtype of HNSCC with a better response to treatment and more favorable prognosis. Mitochondrial function and metabolism vary depending on cancer type and can be related to tumor aggressiveness. This study aims to characterize the metabolism of HPV-positive and HPV-negative HNSCC cell lines. Methods: Oxidative phosphorylation (OXPHOS) and glycolysis were assessed in intact cells, in four HNSCC cell lines using Seahorse XF Analyzer. OXPHOS was further studied in permeabilized cells using high-resolution respirometry in an Oroboros O2K. Metabolomic analysis was performed using mass spectroscopy. Results: The HPV-negative cell lines were found to display a higher OXPHOS capacity and were also able to upregulate glycolysis when needed. The HPV-positive cell line had a higher basal glycolytic rate but lower spare OXPHOS capacity. These cells were also unable to increase respiration in response to succinate, unlike the HPV-negative cells. In the metabolomic analysis, the HPV-positive cells showed a higher kynurenine/tryptophan ratio. Discussion: HPV-positive HNSCC preferred glycolysis to compensate for lower OXPHOS reserves, while the HPV-negative HNSCC displayed a more versatile metabolism, which might be related to increased tumor aggressiveness. The higher kynurenine/tryptophan ratio of HPV-positive HNSCC might be related to increased indoleamine 2,3-dioxygenase activity due to the carcinoma's viral origin. This study highlights important metabolic differences between HPV-positive and HPV-negative cancers and suggests that future metabolic targets for cancer treatment should be individualized based on specific tumor metabolism.

5.
Front Neurol ; 13: 789355, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35370872

RESUMO

Proton magnetic resonance spectroscopy (1H-MRS) provides a non-invasive biochemical profile of brain tumors. The conventional 1H-MRS methods present a few challenges mainly related to limited spatial coverage and low spatial and spectral resolutions. In the recent past, the advent and development of more sophisticated metabolic imaging and spectroscopic sequences have revolutionized the field of neuro-oncologic metabolomics. In this review article, we will briefly describe the scientific premises of three-dimensional echoplanar spectroscopic imaging (3D-EPSI), two-dimensional correlation spectroscopy (2D-COSY), and chemical exchange saturation technique (CEST) MRI techniques. Several published studies have shown how these emerging techniques can significantly impact the management of patients with glioma by determining histologic grades, molecular profiles, planning treatment strategies, and assessing the therapeutic responses. The purpose of this review article is to summarize the potential clinical applications of these techniques in studying brain tumor metabolism.

6.
NMR Biomed ; 35(7): e4719, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35233862

RESUMO

Pseudoprogression (PsP) refers to treatment-related clinico-radiologic changes mimicking true progression (TP) that occurs in patients with glioblastoma (GBM), predominantly within the first 6 months after the completion of surgery and concurrent chemoradiation therapy (CCRT) with temozolomide. Accurate differentiation of TP from PsP is essential for making informed decisions on appropriate therapeutic intervention as well as for prognostication of these patients. Conventional neuroimaging findings are often equivocal in distinguishing between TP and PsP and present a considerable diagnostic dilemma to oncologists and radiologists. These challenges have emphasized the need for developing alternative imaging techniques that may aid in the accurate diagnosis of TP and PsP. In this review, we encapsulate the current state of knowledge in the clinical applications of commonly used metabolic and physiologic magnetic resonance (MR) imaging techniques such as diffusion and perfusion imaging and proton spectroscopy in distinguishing TP from PsP. We also showcase the potential of promising imaging techniques, such as amide proton transfer and amino acid-based positron emission tomography, in providing useful information about the treatment response. Additionally, we highlight the role of "radiomics", which is an emerging field of radiology that has the potential to change the way in which advanced MR techniques are utilized in assessing treatment response in GBM patients. Finally, we present our institutional experiences and discuss future perspectives on the role of multiparametric MR imaging in identifying PsP in GBM patients treated with "standard-of-care" CCRT as well as novel/targeted therapies.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Progressão da Doença , Glioblastoma/diagnóstico por imagem , Glioblastoma/patologia , Glioblastoma/terapia , Humanos , Imageamento por Ressonância Magnética/métodos , Prótons
7.
Environ Sci Technol ; 56(7): 4029-4038, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35302757

RESUMO

Efforts to understand macroplastic pollution have primarily focused on coastal and marine environments to the exclusion of freshwater, terrestrial, and urban ecosystems. To better understand macroplastics in the environment and their sources, a dual approach examining plastic input and leakage can be used. In this study, litter aggregation pathways at 40 survey sites with varying ambient population counts in the Ganges River Basin were surveyed in pre- and postmonsoon seasons. We examine active litter leakage using transect surveys of on-the-ground items, in conjunction with assessments of single-use plastic consumer products at the point of sale. We find that sites with low populations have a significantly higher number of littered items per 1,000 people than those with mid to high populations. Over 75% of litter items were plastics or multimaterial items containing plastic, and tobacco products and plastic food wrappers were the most recorded items. There was no significant variation of litter densities pre- and postmonsoon. Most single-use plastic consumer products were manufactured in-country, but approximately 40% of brands were owned by international companies. Stratified sampling of active litter input and consumer products provides a rapid, replicable snapshot of plastic use and leakage.


Assuntos
Rios , Resíduos , Ecossistema , Monitoramento Ambiental , Humanos , Plásticos , Resíduos/análise
8.
Med Oncol ; 39(1): 13, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34792663

RESUMO

Incidence of human papillomavirus (HPV)-associated oral cancers is on the rise. However, epidemiological data of this subset of cancers are limited. Dental hospital poses a unique advantage in detection of HPV-positive oral malignancies. We assessed the utility of formalin-fixed paraffin-embedded (FFPE) tissues, which are readily available, for evaluation of high-risk HPV infection in oral cancer. For protocol standardization, we used 20 prospectively collected paired FFPE and fresh tissues of histopathologically confirmed oral cancer cases reported in Oral Medicine department of a dental hospital for comparative study. Only short PCRs (~ 200 bp) of DNA isolated using a modified xylene-free method displayed a concordant HPV result. For HPV analysis, we used additional 30 retrospectively collected FFPE tissues. DNA isolated from these specimens showed an overall 23.4% (11/47) HPV positivity with detection of HPV18. Comparison of HPV positivity from dental hospital FFPE specimens with overall HPV positivity of freshly collected oral cancer specimens (n = 55) from three cancer care hospitals of the same region showed notable difference (12.7%; 7/55). Further, cancer hospital specimens showed HPV16 positivity and displayed a characteristic difference in reported sub-sites and patient spectrum. Overall, using a xylene-free FFPE DNA isolation method clubbed with short amplicon PCR, we showed detection of HPV-positive oral cancer in dental hospitals.


Assuntos
Alphapapillomavirus/isolamento & purificação , Instalações Odontológicas , Neoplasias Bucais/diagnóstico , Infecções por Papillomavirus/diagnóstico , Adulto , Idoso , Alphapapillomavirus/genética , DNA Viral/genética , Feminino , Formaldeído , Genótipo , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/patologia , Neoplasias Bucais/virologia , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Inclusão em Parafina , Reação em Cadeia da Polimerase , Prevalência , Fixação de Tecidos
9.
Magn Reson Imaging Clin N Am ; 29(1): 41-52, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33237014

RESUMO

More than one million people in the United States suffer from seizures that are not controlled with antiseizure medications. Targeted interventions such as surgery and deep brain stimulation can confer seizure reduction or even freedom in many of these patients with drug-resistant epilepsy, but success critically depends on identification of epileptogenic zones through MR imaging. Ultrahigh field imaging facilitates improved sensitivity and resolution across many imaging modalities and may facilitate better detection of epileptic markers than is achieved at lower field strengths. The increasing availability and clinical adoption of ultrahigh field scanners play an important role in characterizing drug-resistant epilepsy and planning for its treatment.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Epilepsia/diagnóstico , Epilepsia/fisiopatologia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Humanos
10.
Dev Comp Immunol ; 114: 103800, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32771347

RESUMO

The mechanisms underlying M. fortuitum-induced pathogenesis remains elusive. Using headkidney macrophages (HKM) from Clarias gariepinus, we report that TLR-2-mediated internalization of M. fortuitum is imperative to the induction of pathogenic effects. Inhibiting TLR-2 signalling alleviated HKM apoptosis, thereby favouring bacterial survival. Additionally, TLR-2-mediated cytosolic calcium (Ca2+)c elevation was instrumental for eliciting ER-stress in infected HKM. ER-stress triggered the activation of membrane-proximal calcium entry channels comprising stromal interaction molecule 1 (STIM1) and calcium-release activated calcium channel 1 (Orai1). RNAi studies suggested STIM1-Orai1 signalling initiate calpain-mediated cleavage of nitric oxide synthase interacting protein, prompting the release of pro-apoptotic nitric oxide. Inhibiting STIM1-Orai1 signalling attenuated superoxide production (O2•-) and vice versa. We conclude, TLR-2-induced ER-stress triggers STIM1/Orai1 expression and that the reciprocal association between STIM1-Orai1 signalling and oxidative stress is critical for sustaining (Ca2+)c level, thereby prolonging ER-stress and maintenance of pro-oxidant rich environment to induce HKM apoptosis and bacterial clearance.


Assuntos
Peixes-Gato/imunologia , Doenças dos Peixes/imunologia , Proteínas de Peixes/genética , Rim Cefálico/patologia , Macrófagos/metabolismo , Infecções por Mycobacterium não Tuberculosas/imunologia , Mycobacterium fortuitum/fisiologia , Proteína ORAI1/genética , Molécula 1 de Interação Estromal/genética , Animais , Apoptose , Carga Bacteriana , Cálcio/metabolismo , Células Cultivadas , Proteínas de Peixes/metabolismo , Proteína ORAI1/metabolismo , RNA Interferente Pequeno/genética , Transdução de Sinais , Molécula 1 de Interação Estromal/metabolismo , Superóxidos/metabolismo , Receptor 2 Toll-Like/metabolismo
11.
J Biol Chem ; 295(45): 15245-15252, 2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-32855238

RESUMO

Type-2 diabetes (T2D) is a global disease caused by the inability of pancreatic ß-cells to secrete adequate insulin. However, the molecular mechanisms underlying the failure of ß-cells to respond to glucose in T2D remains unknown. Here, we investigated the relative contribution of UDP-glucose (UDP-G), a P2Y14-specific agonist, in the regulation of insulin release using human isolated pancreatic islets and INS-1 cells. P2Y14 was expressed in both human and rodent pancreatic ß-cells. Dose-dependent activation of P2Y14 by UDP-G suppressed glucose-stimulated insulin secretion (GSIS) and knockdown of P2Y14 abolished the UDP-G effect. 12-h pretreatment of human islets with pertussis-toxin (PTX) improved GSIS and prevented the inhibitory effect of UDP-G on GSIS. UDP-G on GSIS suppression was associated with suppression of cAMP in INS-1 cells. UDP-G decreased the reductive capacity of nondiabetic human islets cultured at 5 mm glucose for 72 h and exacerbated the negative effect of 20 mm glucose on the cell viability during culture period. T2D donor islets displayed a lower reductive capacity when cultured at 5 mm glucose for 72 h that was further decreased in the presence of 20 mm glucose and UDP-G. Presence of a nonmetabolizable cAMP analog during culture period counteracted the effect of glucose and UDP-G. Islet cultures at 20 mm glucose increased apoptosis, which was further amplified when UDP-G was present. UDP-G modulated glucose-induced proliferation of INS-1 cells. The data provide intriguing evidence for P2Y14 and UDP-G's role in the regulation of pancreatic ß-cell function.


Assuntos
AMP Cíclico/biossíntese , Diabetes Mellitus Tipo 2/tratamento farmacológico , Secreção de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/efeitos dos fármacos , Toxina Pertussis/farmacologia , Uridina Difosfato Glucose/antagonistas & inibidores , Animais , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Humanos , Células Secretoras de Insulina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Células Tumorais Cultivadas , Uridina Difosfato Glucose/metabolismo
12.
Sci Rep ; 10(1): 9441, 2020 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-32523022

RESUMO

Bioengineered nanoconjugates have enormous potential as a multifunctional platform for biomedical applications. Conjugation between biotic and abiotic materials enables formulation of nanoconjugates with enhanced physico-chemical properties, increased stability and ability to overcome the inherent shortcomings of individual materials. In this study, we report the preparation and biophysical characterization of an antibacterial system formulated by functionalizing reduced graphene oxide (rGO) with an antimicrobial peptide via covalent as well as non-covalent interaction mechanisms. Environmentally benign synthesis approach was adopted for the formation of rGO, using L-ascorbic acid as a reducing agent. Covalently conjugated peptide-graphitic conjugate displayed improved antibacterial efficacy against Escherichia coli with considerably low cytotoxic activity towards erythrocytes in comparison to self-assembled conjugate and rGO alone. The studies described herein are highly significant in the field of biomaterials and aims to open new avenues of research focusing on a plethora of applications as a prospective non-toxic substitute to conventional antibacterial approaches.


Assuntos
Materiais Biocompatíveis/química , Grafite/farmacologia , Nanocompostos/química , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Óxidos/química , Peptídeos/farmacologia
13.
Eur J Radiol ; 126: 108931, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32146344

RESUMO

PURPOSE: Tumor consistency is a critical factor in surgical planning that influences ease of resection and risk of operative morbidity. The ability of MRI to predict tumor consistency tumor consistency has been shown to increase with higher field strength. The present study examined the utility of 7 T (7 T) MRI in predicting the tumor consistency of pituitary adenomas. METHOD: Fifteen patients with pituitary adenomas were preoperatively scanned at 7 T MRI. Regions of interest were drawn around lesions for voxel-based signal intensity (SI) analysis. The percentage of tumor voxels with intensity higher than local gray matter was calculated on T2-weighted imaging. A single neurosurgeon rated tumor firmness for all patients. Histopathological analysis was performed. Radiological tumor features were correlated with intraoperative tumor consistency measurements and histopathology. RESULTS: Tumors rated as 'soft' intraoperatively were hyperintense to local gray matter on T2-weighted imaging. 'Firm' tumors were hypointense to local gray matter. There was no significant difference in SI ratio between soft and firm tumors (p = 0.098). Soft tumors had a significantly higher percentage of tumor voxels greater than local gray matter compared to firm tumors (p = 0.035, Cohen's D-effect size = 1.208). Soft tumors had higher vascularity than firm tumors, p = 0.015. CONCLUSIONS: The signal and contrast advantage conferred by 7 T MRI may provide valuable preoperative information regarding pituitary tumor consistency and physiology. The use of granular, voxel-based analysis maximizes the potential afforded by the high resolution of 7 T imaging, and may be a valuable method of predicting consistency of pituitary adenoma.


Assuntos
Adenoma/diagnóstico por imagem , Adenoma/patologia , Imageamento por Ressonância Magnética/métodos , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/patologia , Adenoma/cirurgia , Adulto , Idoso , Algoritmos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Hipófise/diagnóstico por imagem , Hipófise/patologia , Hipófise/cirurgia , Neoplasias Hipofisárias/cirurgia , Cuidados Pré-Operatórios/métodos , Estudos Prospectivos
14.
Angew Chem Int Ed Engl ; 59(11): 4354-4359, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-31913559

RESUMO

Herein, for the first time, we present the successful synthesis of a novel two-dimensional corrole-based covalent organic framework (COF) by reacting the unusual approximately T-shaped 5,10,15-tris(p-aminophenyl)corrole H3 TPAPC with terephthalaldehyde, which adopts desymmetrized hcb topology and consists of a staggered AB stacking structure with elliptical pores. The resultant corrole-based COF, TPAPC-COF, exhibits high crystallinity and excellent chemical stability. The combination of extended π-conjugated backbone and interlayer noncovalent π-π interactions endows TPAPC-COF with excellent absorption capability in the entire visible-light and even near-infrared regions. Moreover, this work suggests the promise of TPAPC-COF as a new class of photoactive material for efficient singlet-oxygen generation with potential photodynamic therapy application as demonstrated by in vitro anticancer studies.

15.
Mikrochim Acta ; 187(1): 27, 2019 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-31811393

RESUMO

Peptides exhibit unique binding behavior with graphene and its derivatives by forming bonds on its edges and planes. This makes them useful for sensing and imaging applications. This review with (155 refs.) summarizes the advances made in the last decade in the field of peptide-GO bioconjugation, and the use of these conjugates in analytical sciences and imaging. The introduction emphasizes the need for understanding the biotic-abiotic interactions in order to construct controllable peptide-functionalized graphitic material-based nanotools. The next section covers covalent and non-covalent interactions between peptide and oxidized graphene derivatives along with a discussion of the adsorption events during interfacing. We then describe applications of peptide-graphene conjugates in bioassays, with subsections on (a) detection of cancer cells, (b) monitoring protease activity, (c) determination of environmental pollutants and (d) determination of pathogenic microorganisms. The concluding section describes the current status of peptide functionalized graphitic bioconjugates and addresses future perspectives. Graphical abstractSchematic representation depicting biosensing applications of peptide functionalized graphene oxide.


Assuntos
Técnicas Biossensoriais , Grafite/química , Nanopartículas/química , Neoplasias/patologia , Peptídeos/química , Bactérias/patogenicidade , Poluentes Ambientais/análise , Grafite/metabolismo , Humanos , Nanopartículas/metabolismo , Neoplasias/metabolismo , Peptídeo Hidrolases/metabolismo , Peptídeos/metabolismo
16.
J Neurosurg ; : 1-11, 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31628280

RESUMO

OBJECTIVE: Vision loss remains a debilitating complication of pituitary adenomas, although there is considerable variability in visual impairment before and after decompression surgery. Growing evidence suggests secondary damage to remote visual structures may contribute to vision loss in patients with chiasmatic compression. The present study leverages ultrahigh field 7-T MRI to study the retinotopic organization of the primary visual cortex (V1), and correlates visual defects with cortical thinning in V1 to characterize consequences of pituitary adenomas on the posterior visual system. METHODS: Eight patients (4 males and 4 females, mean age 44.3 years) with pituitary adenomas who exhibited chiasmatic compression and visual field defects, as well as 8 matched healthy controls (4 males and 4 females, mean age 43.3 years), were scanned at 7-T MRI for this prospective study. Whole-brain cortical thickness was calculated using an automated algorithm. A previously published surface-based algorithm was applied to associate the eccentricity and polar angle with each position in V1. Cortical thickness was calculated at each point in the retinotopic organization, and a cortical thickness ratio was generated against matched controls for each point in the visual fields. Patients with adenoma additionally underwent neuroophthalmological examination including 24-2 Humphrey automated visual field perimetry. Pattern deviation (PD) of each point in the visual field, i.e., the deviation in point detection compared with neurologically healthy controls, was correlated with cortical thickness at corresponding polar and eccentricity angles in V1. RESULTS: Whole-brain cortical thickness was successfully derived for all patients and controls. The mean tumor volume was 19.4 cm3. The median global thickness of V1 did not differ between patients (mean ± SD 2.21 ± 0.12 cm), compared with controls (2.06 ± 0.13 cm, p > 0.05). Surface morphometry-based retinotopic maps revealed that all 8 patients with adenoma showed a significant positive correlation between PD and V1 thickness ratios (r values ranged from 0.31 to 0.53, p < 0.05). Mixed-procedure analysis revealed that PD = -8.0719 + 5.5873*[Median V1 Thickness Ratio]. CONCLUSIONS: All 8 patients showed significant positive correlations between V1 thickness and visual defect. These findings provide retinotopic maps of localized V1 cortical neurodegeneration spatially corresponding to impairments in the visual field. These results further characterize changes in the posterior visual pathway associated with chiasmatic compression, and may prove useful in the neuroophthalmological workup for patients with pituitary macroadenoma.

17.
Molecules ; 24(12)2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31248221

RESUMO

Coordination-driven self-assembly is an effective synthetic tool for the construction of spatially and electronically tunable supramolecular coordination complexes (SCCs), which are useful in various applications. Herein, we report the synthesis of a two-dimensional discrete metalla-rectangle [(η6-p-cymene)4Ru4(C6H2O4)2(2)2](CF3SO3)4 (3) by the reaction of a dinuclear half-sandwich ruthenium (II) complex [Ru2(η6-p-cymene)2(C6H2O4)Cl2] (1) and bis-pyridyl amide linker (2) in the presence of AgO3SCF3. This cationic ruthenium metalla-rectangle (3) has been isolated as its triflate salt and characterized by analytical techniques including elemental analysis, Fourier-transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectroscopy (1H-NMR), carbon nuclear magnetic resonance spectroscopy (13C-NMR), 1H-1H correlation spectroscopy (COSY), 1H-1H nuclear Overhauser effect spectroscopy (NOESY), diffusion ordered spectroscopy (DOSY), and high-resolution electrospray ionization mass spectrometry (HR-ESI-MS). Significantly, the 2D cationic ruthenium metalla-rectangle showed better anticancer activity towards three different cell lines (A549, Caki-1 and Lovo) as compared with the parent ruthenium complex (1) and the commercially used drug, cisplatin.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Rutênio , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Complexos de Coordenação/síntese química , Humanos , Estrutura Molecular , Rutênio/química , Espectrometria de Massas por Ionização por Electrospray
18.
Saudi J Anaesth ; 13(1): 9-15, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30692882

RESUMO

BACKGROUND: Whether intraoperative use of hydroxyethyl starch (HES) solutions is associated with postoperative acute kidney injury (AKI) continues to be researched. Urinary neutrophil gelatinase-associated lipocalin (NGAL) is validated for early detection of AKI. Previous studies are limited and use empirically predefined volumes of HES solutions with serum creatinine as marker for AKI. MATERIALS AND METHODS: Adults scheduled for orthopedic surgery under general anesthesia with >200-300 mL blood loss expected were included; 40 were randomized to receive 6% HES 130/0.4 (tetrastarch) (group HES) or Ringer's lactate (group RL) boluses when stroke volume variation (SVV) >10% in supine or lateral position, or >14% in prone position. Incidence of early postoperative AKI using urinary NGAL (>100 ng/mL) was the primary outcome, and using derangement of serum creatinine was the secondary measure. RESULTS: In 38 patients, intervention was completed, and incidence of AKI (postoperative urinary NGAL >100 ng/mL) among them was 0% in both groups. Patients with urinary NGAL >50 ng/mL were insignificantly higher for group RL versus group HES (6/19 vs. 4/19) (P = 0.461), as were those with incidence of AKI as per creatinine values (5/19 vs. 4/19) (P = 1.000). Group RL had significantly higher requirement of fluid (1211 ± 758 mL vs. 689 ± 394 mL) (P = 0.013) and lower cardiac index (P < 0.05) versus group HES. CONCLUSION: SVV-guided tetrastarch and Ringer's lactate do not result in postoperative AKI diagnosed by urinary NGAL >100 ng/mL; however, an insignificant trend for better renal functions as well as significantly more efficacious volume expansion and hemodynamic stability were seen with tetrastarch instead.

19.
J Magn Reson Imaging ; 49(1): 184-194, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29676844

RESUMO

BACKGROUND: Accurate differentiation of brain infections from necrotic glioblastomas (GBMs) may not always be possible on morphologic MRI or on diffusion tensor imaging (DTI) and dynamic susceptibility contrast perfusion-weighted imaging (DSC-PWI) if these techniques are used independently. PURPOSE: To investigate the combined analysis of DTI and DSC-PWI in distinguishing brain injections from necrotic GBMs. STUDY TYPE: Retrospective. POPULATION: Fourteen patients with brain infections and 21 patients with necrotic GBMs. FIELD STRENGTH/SEQUENCE: 3T MRI, DTI, and DSC-PWI. ASSESSMENT: Parametric maps of mean diffusivity (MD), fractional anisotropy (FA), coefficient of linear (CL), and planar anisotropy (CP) and leakage corrected cerebral blood volume (CBV) were computed and coregistered with postcontrast T1 -weighted and FLAIR images. All lesions were segmented into the central core and enhancing region. For each region, median values of MD, FA, CL, CP, relative CBV (rCBV), and top 90th percentile of rCBV (rCBVmax ) were measured. STATISTICAL TESTS: All parameters from both regions were compared between brain infections and necrotic GBMs using Mann-Whitney tests. Logistic regression analyses were performed to obtain the best model in distinguishing these two conditions. RESULTS: From the central core, significantly lower MD (0.90 × 10-3 ± 0.44 × 10-3 mm2 /s vs. 1.66 × 10-3 ± 0.62 × 10-3 mm2 /s, P = 0.001), significantly higher FA (0.15 ± 0.06 vs. 0.09 ± 0.03, P < 0.001), and CP (0.07 ± 0.03 vs. 0.04 ± 0.02, P = 0.009) were observed in brain infections compared to those in necrotic GBMs. Additionally, from the contrast-enhancing region, significantly lower rCBV (1.91 ± 0.95 vs. 2.76 ± 1.24, P = 0.031) and rCBVmax (3.46 ± 1.41 vs. 5.89 ± 2.06, P = 0.001) were observed from infective lesions compared to necrotic GBMs. FA from the central core and rCBVmax from enhancing region provided the best classification model in distinguishing brain infections from necrotic GBMs, with a sensitivity of 91% and a specificity of 93%. DATA CONCLUSION: Combined analysis of DTI and DSC-PWI may provide better performance in differentiating brain infections from necrotic GBMs. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;49:184-194.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Glioblastoma/diagnóstico por imagem , Infecções/diagnóstico por imagem , Angiografia por Ressonância Magnética , Necrose/diagnóstico por imagem , Adulto , Idoso , Anisotropia , Encéfalo/microbiologia , Meios de Contraste/administração & dosagem , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos
20.
Br J Cancer ; 120(1): 54-56, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30478409

RESUMO

EGFRvIII targeted chimeric antigen receptor T (CAR-T) cell therapy has recently been reported for treating glioblastomas (GBMs); however, physiology-based MRI parameters have not been evaluated in this setting. Ten patients underwent multiparametric MRI at baseline, 1, 2 and 3 months after CAR-T therapy. Logistic regression model derived progression probabilities (PP) using imaging parameters were used to assess treatment response. Four lesions from "early surgery" group demonstrated high PP at baseline suggestive of progression, which was confirmed histologically. Out of eight lesions from remaining six patients, three lesions with low PP at baseline remained stable. Two lesions with high PP at baseline were associated with large decreases in PP reflecting treatment response, whereas other two lesions with high PP at baseline continued to demonstrate progression. One patient didn't have baseline data but demonstrated progression on follow-up. Our findings indicate that multiparametric MRI may be helpful in monitoring CAR-T related early therapeutic changes in GBM patients.


Assuntos
Receptores ErbB/imunologia , Glioblastoma/terapia , Imunoterapia Adotiva , Recidiva Local de Neoplasia/terapia , Linhagem Celular Tumoral , Receptores ErbB/antagonistas & inibidores , Feminino , Glioblastoma/diagnóstico por imagem , Glioblastoma/imunologia , Glioblastoma/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/imunologia , Recidiva Local de Neoplasia/patologia , Receptores de Antígenos Quiméricos/imunologia , Receptores de Antígenos Quiméricos/uso terapêutico
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