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1.
Artigo em Inglês | MEDLINE | ID: mdl-38873901

RESUMO

OBJECTIVE: To establish a methodology for objectively estimating the Lens Equatorial Plane (LEP) from clinical images, comparing LEP with dilated versus non-dilated pupils. METHODS: A cohort of 91 eyes from 60 patients undergoing preoperative assessments for cataract surgery was evaluated. Anterior Segment Optical Coherence Tomography (AS-OCT) images were analysed under conditions of pharmacologically induced pupil dilation versus a non-dilated pupil. Geometrical parameters, including LEP, intersection diameter (ID), lens thickness (LT), anterior and posterior lens thickness were automatically calculated by applying standard image processing techniques to clinical AS-OCT images. RESULTS: Significant differences in lens parameters, including LEP, were observed between dilated and non-dilated conditions (all p < 0.001). A strong linear correlation was found across all geometrical variables under both conditions (r[LEP] = 0.64, r[ID] = 0.78, r[LT] = 0.99, all p < 0.001); enabling reliable correction of these differences. CONCLUSION: The study introduces an objective methodology for LEP calculation, emphasising the need to consider the eye's physiological state during preoperative measurements. Incorporating LEP into future intraocular lens (IOL) power calculation formulas and replacing the habitual effective lens position may potentially improve the accuracy of IOL power estimation and thus postoperative visual outcomes.

2.
Antioxidants (Basel) ; 13(6)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38929183

RESUMO

A pathway frequently altered in cancer is glutaminolysis, whereby glutaminase (GA) catalyzes the main step as follows: the deamidation of glutamine to form glutamate and ammonium. There are two types of GA isozymes, named GLS and GLS2, which differ considerably in their expression patterns and can even perform opposing roles in cancer. GLS correlates with tumor growth and proliferation, while GLS2 can function as a context-dependent tumor suppressor. However, both isoenzymes have been described as essential molecules handling oxidant stress because of their involvement in glutathione production. We reviewed the literature to highlight the critical roles of GLS and GLS2 in restraining ROS and regulating both cellular signaling and metabolic stress due to their function as indirect antioxidant enzymes, as well as by modulating both reductive carboxylation and ferroptosis. Blocking GA activity appears to be a potential strategy in the dual activation of ferroptosis and inhibition of cancer cell growth in a ROS-mediated mechanism.

3.
J Cataract Refract Surg ; 50(7): 668-675, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38446495

RESUMO

PURPOSE: To describe gender differences in the biometric parameters of a large sample of patients with cataract. Cataract surgery has evolved from a vision restoration to a refractive procedure, and population-based studies are vital to optimize normative databases and postsurgical outcomes. SETTING: Miguel Servet University Hospital, Zaragoza, Spain. DESIGN: Retrospective single-center observational study. METHODS: The study included 34 589 eyes (20 004 patients with cataract). Biometric data were obtained from IOL Master 700 and Pentacam HR. Linear mixed models were used to account for intereye correlation. HofferQST formula was used to calculate the hypothetical distribution of intraocular lens (IOL) power (arbitrary lens; A = 119.2). RESULTS: Most biometric variables showed significant differences between sexes ( P < .0001), such as 0.53 mm shorter eyes found in females, of which 0.16 mm are explained by shorter aqueous depth. Steeper anterior keratometries (∼0.75 diopter [D]) were found in women, to end up in no difference on anterior astigmatism magnitude, but different orientation ( P < .0001). The distribution of IOL power differed between sexes ( P < .001), with the interquartile range shifting 1 D toward more powerful lenses in women and odds ratio (power >26 D) = 2.26, P < .0001 (Fisher). CONCLUSIONS: Large sample size studies provide smaller margin of error, higher power, and controlled risk of reporting false (negative or positive) findings. Highly significant differences between sexes in ocular biometry were found; this supports the idea that including sex as a parameter in IOL calculation should be explored and may improve results. In addition, the distribution of IOL powers was provided, which may be useful for manufacturers and hospital stock planning.


Assuntos
Biometria , Lentes Intraoculares , Humanos , Masculino , Estudos Retrospectivos , Feminino , Idoso , Facoemulsificação , Implante de Lente Intraocular , Pessoa de Meia-Idade , Extração de Catarata , Refração Ocular/fisiologia , Fatores Sexuais , Catarata , Idoso de 80 Anos ou mais , Acuidade Visual/fisiologia , Comprimento Axial do Olho/patologia , Óptica e Fotônica
4.
Cancers (Basel) ; 15(2)2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36672480

RESUMO

Most tumor cells can use glutamine (Gln) for energy generation and biosynthetic purposes. Glutaminases (GAs) convert Gln into glutamate and ammonium. In humans, GAs are encoded by two genes: GLS and GLS2. In glioblastoma, GLS is commonly overexpressed and considered pro-oncogenic. We studied the metabolic effects of inhibiting GLS activity in T98G, LN229, and U87MG human glioblastoma cell lines by using the inhibitor CB-839. We performed metabolomics and isotope tracing experiments using U-13C-labeled Gln, as well as 15N-labeled Gln in the amide group, to determine the metabolic fates of Gln carbon and nitrogen atoms. In the presence of the inhibitor, the results showed an accumulation of Gln and lower levels of tricarboxylic acid cycle intermediates, and aspartate, along with a decreased oxidative labeling and diminished reductive carboxylation-related labeling of these metabolites. Additionally, CB-839 treatment caused decreased levels of metabolites from pyrimidine biosynthesis and an accumulation of intermediate metabolites in the de novo purine nucleotide biosynthesis pathway. The levels of some acetylated and methylated metabolites were significantly increased, including acetyl-carnitine, trimethyl-lysine, and 5-methylcytosine. In conclusion, we analyzed the metabolic landscape caused by the GLS inhibition of CB-839 in human glioma cells, which might lead to the future development of new combination therapies with CB-839.

5.
J Am Geriatr Soc ; 71(1): 36-45, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36302724

RESUMO

BACKGROUND/OBJECTIVES: Hospitalization due to acute illness in older patients is often associated with anxiety or depressive symptoms. In these circumstances, given that pharmacologic treatment should be avoided to reduce interactions with ongoing medication regimes, psychotherapy techniques should be considered. The purpose of this study was to evaluate the effectiveness of group reminiscence therapy (RT) on the reduction of anxiety and depressive symptoms in acutely hospitalized older patients. METHODS: Controlled and prospective study conducted on the Acute Geriatric Unit of a university hospital. Patients included in the intervention group (RT Group) attended a group session focused on RT, whereas those included in the control group (UC) received usual hospital care. Exclusion criteria were severe cognitive impairment, impossibility to mobilize, and clinical/hemodynamic instability. The intervention was based on a multi-task daily group session of reminiscence activities. The severity of anxiety (Hamilton Anxiety Rating Scale, HAM-A), depressive symptoms (15-item Geriatric Depression Scale, GDS-15), loneliness (ESTE-II social loneliness scale), and fear of death (Collet-Lester scale) was assessed at admission and discharge in both groups. RESULTS: The intervention was effective in reducing the proportion of patients with anxiety and depressive symptoms during hospitalization. The proportion of patients with moderate-severe anxiety at discharge was 32.1% in the UC and 13.4% in the RT Group (p < 0.001), whereas the proportion of patients with depressive symptoms at discharge was 49.1% in the UC and 19.5% in the RT Group (p < 0.001). The intervention was independently associated with benefits on anxiety levels (RR 2.45, 95% CI 1.83-3.28) and depression (RR 3.71, 95% CI 2.22-6.19) at discharge. No differences were found in loneliness or fear of death. CONCLUSIONS: A group reminiscence activity reduces the proportion of patients with anxiety and depressive symptoms during hospitalization for an acute disease. Absolute changes in both anxiety and depression scores, even though significant, were relatively small.


Assuntos
Depressão , Psicoterapia , Humanos , Idoso , Depressão/psicologia , Estudos Prospectivos , Psicoterapia/métodos , Ansiedade/terapia , Hospitalização
6.
Diagnostics (Basel) ; 12(7)2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35885610

RESUMO

BACKGROUND: Plantar fibromatosis, known as Ledderhose disease, is a neoplastic disease characterized by a locally-aggressive bland fibroblastic proliferation. Although Pacinian corpuscles alterations are commonly described in palmar fibromatosis, there are still no references about Pacinian corpuscles alterations in the rarer plantar version. METHODS: We present a case report where a wide cutaneous resection, including the plantar fascia was performed, allowing a detailed study of Pacinian corpuscles. Pacinian corpuscles were analyzed using immunohistochemistry for neurofilament proteins, S100 protein, CD34, vimentin, glucose transporter 1, epithelial membrane antigen, neural-cell adhesion molecule, actin, desmin, type IV collagen, and high-affinity neurotrophin Trk-receptors. Moreover, the density and the size of the corpuscles were determined. RESULTS: A clear increase in the number (hyperplasia) of Pacinian corpuscles was evidenced in the Ledderhose disease plantar fascia in comparison with similarly aged normal subjects. Pacinian hypertrophy was not demonstrated, but a significant decrease in the number of corpuscular lamellae was noted, with a subsequent increase in the interlamellar spaces. Pacinian corpuscles from the pathological plantar fascia showed an abnormal structure and immunohistochemical profile, generally without identifiable axons, and also absence of an inner core or an intermediate layer. Moreover, other molecules related with trophic maintenance of corpuscles were also absent. Finally, a vascular proliferation was commonly noted in some corpuscles, which involved all corpuscular constituents. CONCLUSION: The observed Pacinian corpuscles hyperplasia could be considered a diagnostic clue of plantar fibromatosis.

7.
Front Endocrinol (Lausanne) ; 13: 926668, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35846298

RESUMO

Purpose: Infertility is a major problem affecting children, adolescents, and young adults (AYAs) with cancer, either due to the disease itself or because of oncologic treatment. Oncofertility (OF) focuses on counseling cancer patients about fertility risks and preservation options. However, OF and fertility preservation (FP) conversations on Twitter and their impact are unknown. We aim to characterize the users and type of content of these conversations. Materials and Methods: This observational study analyzed tweets with the hashtags "#Oncofertility" and "#FertilityPreservation" over eight months. We classified Twitter accounts by user type and country. Tweets were categorized by content type, and retweets and likes were quantified. Descriptive statistics were used for analysis. Results: A total of 399 tweets from 223 different accounts were evaluated. Twitter accounts comprised 22 countries and stemmed from high, upper-middle, and lower-middle-income countries in 86.5%, 5.4%, and 6.3%, respectively; no accounts from low-income countries were found. Accounts were mostly from physicians (37%) and healthcare centers (20%); we did not find any patient accounts. The most common content category was informative tweets directed to patients (30.8%), followed by discussion/sharing of medical papers (25.6%). Only 14.5% of tweets contained information about children and adolescents. Still, only 4.5% were aimed at children. Retweets were absent in 16.5% of the tweets, and 80.7% did not have comments. Conclusion: OF and FP discussions on Twitter were limited to interactions among medical professionals. Also, advocacy groups showed limited activity on social media. Even though a significant proportion of tweets directed to patients were found, no active involvement of patients was observed. Finally, limited number of tweets (4.5%) were directed to children and adolescents. There is a need to raise awareness about the effects of cancer on fertility in this group. Currently, Twitter is not a resource of information for children and AYAs with cancer who need OF counseling and fertility preservation. Our results open a debate on how to promote the use of social media in the future to improve the quality of OF information available, awareness, and care since there is an unmet need for fertility preservation access in young cancer patients.


Assuntos
Preservação da Fertilidade , Neoplasias , Médicos , Mídias Sociais , Adolescente , Criança , Humanos , Neoplasias/complicações , Neoplasias/terapia
8.
Endoscopy ; 54(6): 629, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35613613
9.
JCO Glob Oncol ; 8: e2100299, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35258989

RESUMO

PURPOSE: Global Oncology is the movement to improve equitable access to cancer control and care, recognizing challenges because of economic and social factors between high-, middle-, and low-income countries (HIC, MIC, and LIC, respectively). The JCO Global Oncology (JCO GO) is a major platform dedicated to publishing peer-reviewed research relevant to populations with limited resources. To assess the success of its goals of encouraging global interaction and increasing MIC and LIC engagement, we analyzed authorship and readership patterns. METHODS: Metadata of logged views between January 1, 2018, and June 30, 2019, of articles published in 2018 by JCO GO were identified using Google Analytics. The country of origin of each author and those who accessed the journal were categorized according to the 2019 income group World Bank Classification (WBC). RESULTS: One hundred thirty-two articles were published in JCO GO in 2018. Corresponding authors came from 34 nations: 35% HIC, 47% MIC, and 18% LIC. The top publishing countries were the United States, India, Brazil, Mexico, and Nigeria. Article authors were solely from within one WBC group in 41% (23% HIC, 16% MIC, and 2% LIC). In those with mixed-WBC authorship origins, collaborations were 42% HIC + MIC, 11% HIC + LIC, and 6% HIC + MIC + LIC, but none with MIC + LIC. Regarding viewing, 87,860 views originated from 180 countries (82% of the WBC list): 35% HIC, 51% MIC, and 14% LIC. The most common accessing nations were the United States, India, the United Kingdom, Brazil, and Ethiopia. CONCLUSION: More than half of JCO GO's authorship comes from mixed WBC groups, with viewership extending to most of the world's nations. Areas to address are low level of LIC corresponding authors, few papers from authors across all WBC groups, no publications from MIC + LIC collaborations, and a low percentage of readership by LIC. These data provide focus to target interventions aimed at reducing the academic segregation of LIC and improving interactions across all WBC countries.


Assuntos
Autoria , Publicações , Renda , Oncologia , Pobreza
10.
Endosc Int Open ; 9(10): E1466-E1471, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34540537

RESUMO

Background and study aims Endoscopic ultrasound-guided fine needle biopsy (EUS-FNB) is recommended after non-diagnostic biopsy in gastrointestinal wall thickening, although the performance of currently available FNB needles in this setting is unknown. We aimed to assess the diagnostic accuracy and safety of EUS-FNB and to evaluate the "T" wall staging in malignant pathology. Patients and methods This was a single center retrospective study that included all consecutive patients undergoing EUS-FNB for diffuse gastrointestinal wall thickening with at least one previous negative conventional endoscopic biopsy between January 2016 and November 2019. EUS-FNB was performed using linear-array echoendoscopes with slow-pull/fanning technique. Tissue acquisition was done with 19- or 22-gauge biopsy needles. Samples were included in formalin without rapid on-site evaluation and submitted for histopathological processing. The final diagnosis was based on conclusive histology or absence of evidence of disease progression after follow-up at least 6 months. Results Twenty-nine patients (21 men), with a median age of 68 (IQR: 56-77), were included. EUS-FNB was technically feasible and the sample quality was adequate for full histological assessment in all patients (100 %). Sensitivity, specificity, positive and negative predictive values, and overall accuracy for diagnosis of malignancy were 95.5 %, 100 %, 100 %, 83.3 %, and 96.3 %, respectively. In patients with malignant disease, the samples obtained allowed detection of signs of deep layer infiltration ("histological staging") in 17 of 21 cases (81 %). No adverse events were noted. Conclusions The EUS-FNB technique demonstrated excellent diagnostic performance and safety in the study of unexplained diffuse gastrointestinal wall thickening. Histological staging was obtained in a high percentage of samples.

11.
Neurochem Int ; 149: 105136, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34274381

RESUMO

Glioblastoma remains one of the most challenging and devastating cancers, with only a very small proportion of patients achieving 5-year survival. The current standard of care consists of surgery, followed by radiation therapy with concurrent and maintenance chemotherapy with the alkylating agent temozolomide. To date, this drug is the only one that provides a significant survival benefit, albeit modest, as patients end up acquiring resistance to this drug. As a result, tumor progression and recurrence inevitably occur, leading to death. Several factors have been proposed to explain this resistance, including an upregulated antioxidant system to keep the elevated intracellular ROS levels, a hallmark of cancer cells, under control. In this review, we discuss the mechanisms of chemoresistance -including the important role of glioblastoma stem cells-with emphasis on antioxidant defenses and how agents that impair redox balance (i.e.: sulfasalazine, erastin, CB-839, withaferin, resveratrol, curcumin, chloroquine, and hydroxychloroquine) might be advantageous in combined therapies against this type of cancer.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Antioxidantes/metabolismo , Neoplasias Encefálicas/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Glioblastoma/metabolismo , Temozolomida/uso terapêutico , Animais , Antineoplásicos Alquilantes/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/fisiologia , Glioblastoma/tratamento farmacológico , Humanos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Temozolomida/farmacologia
12.
J Biomed Sci ; 28(1): 14, 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33610185

RESUMO

BACKGROUND: Glutaminase isoenzymes GLS and GLS2 play apparently opposing roles in cancer: GLS acts as an oncoprotein, while GLS2 (GAB isoform) has context specific tumour suppressive activity. Some microRNAs (miRNAs) have been implicated in progression of tumours, including gliomas. The aim was to investigate the effect of GLS and GAB expression on both miRNAs and oxidative status in glioblastoma cells. METHODS: Microarray profiling of miRNA was performed in GLS-silenced LN229 and GAB-transfected T98G human glioblastoma cells and their wild-type counterparts. Results were validated by real-time quantitative RT-PCR. Oxidative status and antioxidant enzymes were determined by spectrophotometric or fluorescence assays in GLS-silenced LN229 and T98G, and GAB-transfected LN229 and T98G. RESULTS: MiRNA-146a-5p, miRNA-140-3p, miRNA-21-5p, miRNA-1260a, and miRNA-92a-3p were downregulated, and miRNA-1246 was upregulated when GLS was knocked down. MiRNA-140-3p, miRNA-1246, miRNA-1260a, miRNA-21-5p, and miRNA-146a-5p were upregulated when GAB was overexpressed. Oxidative status (lipid peroxidation, protein carbonylation, total antioxidant capacity, and glutathione levels), as well as antioxidant enzymes (catalase, superoxide dismutase, and glutathione reductase) of silenced GLS glioblastoma cells and overexpressed GAB glioblastoma cells significantly changed versus their respective control glioblastoma cells. MiRNA-1246, miRNA-1260a, miRNA-146a-5p, and miRNA-21-5p have been characterized as strong biomarkers of glioblastoma proliferation linked to both GLS silencing and GAB overexpression. Total glutathione is a reliable biomarker of glioblastoma oxidative status steadily associated to both GLS silencing and GAB overexpression. CONCLUSIONS: Glutaminase isoenzymes are related to the expression of some miRNAs and may contribute to either tumour progression or suppression through certain miRNA-mediated pathways, proving to be a key tool to switch cancer proliferation and redox status leading to a less malignant phenotype. Accordingly, GLS and GAB expression are especially involved in glutathione-dependent antioxidant defence.


Assuntos
Regulação Neoplásica da Expressão Gênica , Glioblastoma/metabolismo , Glutaminase/genética , MicroRNAs/metabolismo , Estresse Oxidativo , Linhagem Celular Tumoral , Regulação para Baixo , Glutaminase/metabolismo , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Regulação para Cima
14.
Endosc Int Open ; 8(9): E1194-E1201, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32904815

RESUMO

Background and study aims Endoscopic ultrasound-guided gastroenterostomy (EUS-GE) with a lumen-apposing metal stent (LAMS) is a novel, minimally invasive technique in the palliative treatment of malignant gastric outlet obstruction (GOO). Several studies have demonstrated feasibility and safety of EUS-GE, but evidence on long-term durability is limited. The aim of this study was to evaluate patency of EUS-GE in treatment of malignant GOO. Patients and Methods An international multicenter study was performed in seven centers in four European countries. Patients who underwent EUS-GE with a LAMS between March 2015 and March 2019 for palliative treatment of symptomatic malignant GOO were included retrospectively. Our main outcome was recurrent obstruction due to LAMS dysfunction; other outcomes of interest were technical success, clinical success, adverse events (AEs), and survival. Results A total of 45 patients (mean age 69.9 ±â€Š12.3 years and 48.9 % male) were included. Median duration of follow-up was 59 days (interquartile range [IQR] 41-128). Recurrent obstruction occurred in two patients (6.1 %), after 33 and 283 days of follow-up. Technical success was achieved in 39 patients (86.7 %). Clinical success was achieved in 33 patients (73.3 %). AEs occurred in 12 patients (26.7 %), of which five were fatal. Median overall survival was 57 days (IQR 32-114). Conclusions EUS-GE showed a low rate of recurrent obstruction. The relatively high number of fatal AEs underscores the importance of careful implementation of EUS-GE in clinical practice.

15.
Sci Rep ; 10(1): 2259, 2020 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-32042057

RESUMO

Glutaminase (GA) catalyzes the first step in mitochondrial glutaminolysis playing a key role in cancer metabolic reprogramming. Humans express two types of GA isoforms: GLS and GLS2. GLS isozymes have been consistently related to cell proliferation, but the role of GLS2 in cancer remains poorly understood. GLS2 is repressed in many tumor cells and a better understanding of its function in tumorigenesis may further the development of new therapeutic approaches. We analyzed GLS2 expression in HCC, GBM and neuroblastoma cells, as well as in monkey COS-7 cells. We studied GLS2 expression after induction of differentiation with phorbol ester (PMA) and transduction with the full-length cDNA of GLS2. In parallel, we investigated cell cycle progression and levels of p53, p21 and c-Myc proteins. Using the baculovirus system, human GLS2 protein was overexpressed, purified and analyzed for posttranslational modifications employing a proteomics LC-MS/MS platform. We have demonstrated a dual targeting of GLS2 in human cancer cells. Immunocytochemistry and subcellular fractionation gave consistent results demonstrating nuclear and mitochondrial locations, with the latter being predominant. Nuclear targeting was confirmed in cancer cells overexpressing c-Myc- and GFP-tagged GLS2 proteins. We assessed the subnuclear location finding a widespread distribution of GLS2 in the nucleoplasm without clear overlapping with specific nuclear substructures. GLS2 expression and nuclear accrual notably increased by treatment of SH-SY5Y cells with PMA and it correlated with cell cycle arrest at G2/M, upregulation of tumor suppressor p53 and p21 protein. A similar response was obtained by overexpression of GLS2 in T98G glioma cells, including downregulation of oncogene c-Myc. Furthermore, human GLS2 was identified as being hypusinated by MS analysis, a posttranslational modification which may be relevant for its nuclear targeting and/or function. Our studies provide evidence for a tumor suppressor role of GLS2 in certain types of cancer. The data imply that GLS2 can be regarded as a highly mobile and multilocalizing protein translocated to both mitochondria and nuclei. Upregulation of GLS2 in cancer cells induced an antiproliferative response with cell cycle arrest at the G2/M phase.


Assuntos
Carcinogênese/metabolismo , Pontos de Checagem do Ciclo Celular , Diferenciação Celular , Glutaminase/fisiologia , Neoplasias/metabolismo , Animais , Células COS , Linhagem Celular Tumoral , Proliferação de Células , Chlorocebus aethiops , Células Hep G2 , Humanos
16.
Curr Med Chem ; 27(32): 5317-5339, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31038055

RESUMO

BACKGROUND: Metabolic reprogramming of tumours is a hallmark of cancer. Among the changes in the metabolic network of cancer cells, glutaminolysis is a key reaction altered in neoplasms. Glutaminase proteins control the first step in glutamine metabolism and their expression correlates with malignancy and growth rate of a great variety of cancers. The two types of glutaminase isoenzymes, GLS and GLS2, differ in their expression patterns and functional roles: GLS has oncogenic properties and GLS2 has been described as a tumour suppressor factor. RESULTS: We have focused on glutaminase connections with key oncogenes and tumour suppressor genes. Targeting glutaminase isoenzymes includes different strategies aimed at deactivating the rewiring of cancer metabolism. In addition, we found a long list of metabolic enzymes, transcription factors and signalling pathways dealing with glutaminase. On the other hand, a number of chemicals have been described as isoenzyme-specific inhibitors of GLS and/or GLS2 isoforms. These molecules are being characterized as synergic and therapeutic agents in many types of tumours. CONCLUSION: This review states the metabolic pathways that are rewired in cancer, the roles of glutaminase isoforms in cancer, as well as the metabolic circuits regulated by glutaminases. We also show the plethora of anticancer drugs that specifically inhibit glutaminase isoenzymes for treating several sets of cancer.


Assuntos
Neoplasias , Carcinogênese , Glutaminase , Humanos , Isoenzimas , Neoplasias/tratamento farmacológico
18.
Front Neurorobot ; 13: 58, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31417390

RESUMO

Hybrid orthoses or rehabilitation exoskeletons have proven to be a powerful tool for subjects with gait disabilities due to their combined use of electromechanical actuation to provide motion and support, and functional electrical stimulation (FES) to contract muscle tissue so as to improve the rehabilitation process. In these devices, each degree of freedom is governed by two actuators. The main issue arises in the design of the two actuation profiles for there to be natural or normative gait motion in which the two actuators are transparent to each other. Hybrid exoskeleton control solutions proposed in the literature have been based on tracking the desired kinematics and applying FES to maintain the desired motion rather than to attain the values expected for physiological movement. This work proposes a muscle-model approach involving inverse dynamics optimization for the design of combined actuation in hybrid orthoses. The FES profile calculated in this way has the neurophysiological meaningfulness for the device to be able to fulfill its rehabilitative purpose. A general scheme is proposed for a hybrid hip-knee-ankle-foot orthosis. The actuation profiles, when muscle tissue is fatigued due to FES actuation are analyzed, and an integrated approach is presented for estimating the actuation profiles so as to overcome muscle peak force reduction during stimulation. The objective is to provide a stimulation profile for each muscle individually that is compatible with the desired kinematics and actuation of the orthosis. The hope is that the results may contribute to the design of subject-specific rehabilitation routines with hybrid exoskeletons, improving the exoskeleton's actuation while maintaining its rehabilitative function.

19.
J Neuropathol Exp Neurol ; 77(12): 1122-1136, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30364991

RESUMO

In congenital hydrocephalus, cerebrospinal fluid accumulation is associated with increased intracranial pressure (ICP), ischemia/hypoxia, metabolic impairment, neuronal damage, and astrocytic reaction. The aim of this study was to identify whether a metabolite profile revealing tissue responses according to the severity of hydrocephalus can be detected. The hyh mutant mouse used for this study exhibits 2 different forms of hydrocephalus, severe and moderate. In a comprehensive investigation into the 2 progressions of hydrocephalus, mice with severe hydrocephalus were found to have higher ICP and astrocytic reaction. Several metabolites from the mouse brain cortex were analyzed with 1H high-resolution magic angle spinning nuclear magnetic resonance (1H HR-MAS NMR) spectroscopy. A differential profile for metabolites including glutamate and glutamine was found to correlate with the severity of hydrocephalus and can be explained due to differential astrocytic reactions, neurodegenerative conditions, and the presence of ischemia. The glutamate transporter EAAT2 and the metabolite taurine were found to be key histopathological markers of affected parenchymata. In conclusion, a differential metabolite profile can be detected according to the severity of hydrocephalus and associated ICP and therefore can be used to monitor the efficacy of experimental therapies.


Assuntos
Hidrocefalia/genética , Hidrocefalia/patologia , Metaboloma/fisiologia , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/patologia , Índice de Gravidade de Doença , Animais , Feminino , Hidrocefalia/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Doenças Neurodegenerativas/metabolismo
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