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1.
Sensors (Basel) ; 23(2)2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36679552

RESUMO

Diabetes mellitus presents a high prevalence around the world. A common and long-term derived complication is diabetic foot ulcers (DFUs), which have a global prevalence of roughly 6.3%, and a lifetime incidence of up to 34%. Infrared thermograms, covering the entire plantar aspect of both feet, can be employed to monitor the risk of developing a foot ulcer, because diabetic patients exhibit an abnormal pattern that may indicate a foot disorder. In this study, the publicly available INAOE dataset composed of thermogram images of healthy and diabetic subjects was employed to extract relevant features aiming to establish a set of state-of-the-art features that efficiently classify DFU. This database was extended and balanced by fusing it with private local thermograms from healthy volunteers and generating synthetic data via synthetic minority oversampling technique (SMOTE). State-of-the-art features were extracted using two classical approaches, LASSO and random forest, as well as two variational deep learning (DL)-based ones: concrete and variational dropout. Then, the most relevant features were detected and ranked. Subsequently, the extracted features were employed to classify subjects at risk of developing an ulcer using as reference a support vector machine (SVM) classifier with a fixed hyperparameter configuration to evaluate the robustness of the selected features. The new set of features extracted considerably differed from those currently considered state-of-the-art but provided a fair performance. Among the implemented extraction approaches, the variational DL ones, particularly the concrete dropout, performed the best, reporting an F1 score of 90% using the aforementioned SVM classifier. In comparison with features previously considered as the state-of-the-art, approximately 15% better performance was achieved for classification.


Assuntos
Diabetes Mellitus , Pé Diabético , Humanos , Pé Diabético/diagnóstico ,
2.
Mol Microbiol ; 115(5): 1039-1053, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33665906

RESUMO

Giardia duodenalis is a parasite of great medical interest due to the number of infections it causes worldwide each year. Although research on epigenetic mechanisms in this protist has only begun recently, epigenetic regulation has already been shown to have important roles in encystation, antigenic variation, and resistance to antibiotics in Giardia. In this work, we show that a Giardia ortholog of Sir2, GdSir2.4, is involved in the silencing of rRNA expression. Our results demonstrate that GdSir2.4 localizes to the nucleolus, and its binding to the intergenic spacer region of the rDNA is associated with the deacetylation of the chromatin in this region. Given the importance of the regulation of rRNA expression to maintain adequate levels of ribosomes and genomic stability within the cells, GdSir2.4 can be considered a target to create new therapeutic agents against this parasite.


Assuntos
DNA Ribossômico/genética , Giardia lamblia/metabolismo , Proteínas de Protozoários/metabolismo , RNA de Protozoário/genética , Sirtuínas/metabolismo , Transcrição Gênica , Cromatina/metabolismo , DNA Ribossômico/metabolismo , Epigênese Genética , Regulação da Expressão Gênica , Inativação Gênica , Giardia lamblia/genética , Giardíase/parasitologia , Humanos , Proteínas de Protozoários/genética , RNA de Protozoário/metabolismo , Sirtuínas/genética
3.
Sensors (Basel) ; 21(3)2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-33573296

RESUMO

Thermography enables non-invasive, accessible, and easily repeated foot temperature measurements for diabetic patients, promoting early detection and regular monitoring protocols, that limit the incidence of disabling conditions associated with diabetic foot disorders. The establishment of this application into standard diabetic care protocols requires to overcome technical issues, particularly the foot sole segmentation. In this work we implemented and evaluated several segmentation approaches which include conventional and Deep Learning methods. Multimodal images, constituted by registered visual-light, infrared and depth images, were acquired for 37 healthy subjects. The segmentation methods explored were based on both visual-light as well as infrared images, and optimization was achieved using the spatial information provided by the depth images. Furthermore, a ground truth was established from the manual segmentation performed by two independent researchers. Overall, the performance level of all the implemented approaches was satisfactory. Although the best performance, in terms of spatial overlap, accuracy, and precision, was found for the Skin and U-Net approaches optimized by the spatial information. However, the robustness of the U-Net approach is preferred.


Assuntos
Aprendizado Profundo , Diabetes Mellitus , Pé Diabético , Doenças do Pé , Pé Diabético/diagnóstico por imagem , Diagnóstico Precoce , Pé/diagnóstico por imagem , Humanos , Termografia
4.
Sensors (Basel) ; 21(7)2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33804926

RESUMO

This work presents a revision of four different registration methods for thermal infrared and visible images captured by a camera-based prototype for the remote monitoring of diabetic foot. This prototype uses low cost and off-the-shelf available sensors in thermal infrared and visible spectra. Four different methods (Geometric Optical Translation, Homography, Iterative Closest Point, and Affine transform with Gradient Descent) have been implemented and analyzed for the registration of images obtained from both sensors. All four algorithms' performances were evaluated using the Simultaneous Truth and Performance Level Estimation (STAPLE) together with several overlap benchmarks as the Dice coefficient and the Jaccard index. The performance of the four methods has been analyzed with the subject at a fixed focal plane and also in the vicinity of this plane. The four registration algorithms provide suitable results both at the focal plane as well as outside of it within 50 mm margin. The obtained Dice coefficients are greater than 0.950 in all scenarios, well within the margins required for the application at hand. A discussion of the obtained results under different distances is presented along with an evaluation of its robustness under changing conditions.


Assuntos
Diabetes Mellitus , Pé Diabético , Algoritmos , Pé Diabético/diagnóstico por imagem , , Humanos , Monitorização Fisiológica , Termografia
5.
Exp Parasitol ; 209: 107822, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31863745

RESUMO

Giardia duodenalis is a flagellated unicellular eukaryotic microorganism that commonly causes diarrheal disease throughout the world. Treatment of giardiasis is limited to nitroheterocyclic compounds as metronidazole and benzimidazoles as albendazole, where remarkably treatment failure is relatively common. Consequently, the need for new options to treat this disease is underscored. We predicted by a bioinformatic approach that nicotinamide inhibits Giardia sirtuins by the nicotinamide exchange pathway, and since sirtuins are involved in cell cycle control, they could be related with arrest and decrease of viability. When trophozoites were treated with nicotinamide (NAM), a strong arrest of Giardia trophozoites in G2 phase was observed and at the same time changes in transcriptional expression of sirtuins were produced. Interestingly, the G2 arrest is not related to double-strand breaks, which strengthens the role of sirtuins in the control of the Giardia cell cycle. Results with NAM-treated trophozoites as predicted demonstrate antigiardial effects and thus open new options for the treatment of giardiasis, either with the combination of nicotinamide with another antigiardial drug, or with the design of specific inhibitors for Giardia sirtuins.


Assuntos
Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Giardia lamblia/efeitos dos fármacos , Niacinamida/farmacologia , Sirtuínas/metabolismo , Complexo Vitamínico B/farmacologia , Sequência de Aminoácidos , Giardia lamblia/citologia , Giardia lamblia/genética , Giardia lamblia/metabolismo , Humanos , Alinhamento de Sequência , Sirtuínas/antagonistas & inibidores , Sirtuínas/química , Sirtuínas/genética
7.
Sensors (Basel) ; 20(7)2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32252309

RESUMO

Microwave thermometry is a noninvasive and passive technique for measuring internal body temperature. Wearable compact antennas, matched to the specific body area, are required for this method. We present a new epidermal wideband antenna for medical radiometry. The double asymmetric H-shaped slot antenna was designed to be matched to different parts of the body without fat layers. The slots are fed by a short-circuited microstrip line in order to decrease size and back radiation, thus reducing potential interferences. In this way, contribution to radiometric temperature due to back radiation is lower than 4%, versus the 20% of the volume under investigation, over the whole operating frequency band. The designed prototype was manufactured on a flexible substrate. The antenna is a very small size, to make it comfortable and suitable for being used by patients with different body mass indexes. The double H-shaped antenna shows good wideband matching results from around 1.5 GHz up to 5 GHz, in different body locations such as the neck, foot instep and foot sole.


Assuntos
Temperatura Corporal/fisiologia , Radiação Eletromagnética , Radiometria , Termometria , Humanos , Micro-Ondas/uso terapêutico , Tecnologia sem Fio
8.
J Cell Physiol ; 234(5): 5524-5536, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30272821

RESUMO

Mutations in p53 are strongly associated with several highly malignant cancer phenotypes but its role in regulating energy metabolism has not been completely elucidated. The effect on glycolysis and oxidative phosphorylation (OxPhos) of mutant p53R248Q overexpression in HeLa cells (HeLa-M) was analyzed and compared with cells overexpressing wild-type p53 (HeLa-H) and nontransfected cells containing negligible p53 levels (HeLa-L). p53 R248Q overexpression induced early cell detachment during in vitro growth; however, detached HeLa-M cells showed high viability, shorter generation time and significant diminution in the adhesion proteins E-cadherin and ß-catenin versus HeLa-H and HeLa-L cells. Under normoxia, a lower growth rate of attached HeLa-M cells correlated with decreased levels of proliferating cell nuclear antigen (PCNA), peroxisome proliferator-activated receptor gamma coactivator 1-α (PGC-1α), adenosine monophosphate-activated protein kinase (AMPK), mitochondrial proteins (20-80%) and OxPhos flux (69 ± 12%). On the contrary, HeLa-M also showed increased contents of CDKN1A, nuclear factor κB (NF-κB), c-MYC, hypoxia-inducible factor 1-α (HIF-1α; 1-4 times), glycolytic HIF-1α targets (2-4 times), and glycolysis flux (2-fold) versus HeLa-H. In consequence, glycolysis provided ~70% of the cellular adenosine triphosphate (ATP) in HeLa-M cells under normoxia whereas, OxPhos predominated (65-82%) in HeLa-H and HeLa-L cells. Pifithrin-α, a specific p53 inhibitor, did not alter the p53 R248Q target protein contents and OxPhos and glycolytic fluxes, and a poor HIF-1α-p53 R248Q interaction was attained, in HeLa-M cells. These observations suggested that p53 R248Q deficiently interacted with pifithrin-α and HIF-1α. Therefore, lower mitochondrial biogenesis, deficient HIF-1α/mutant p53 interaction, and development of a pseudohypoxic state under normoxia were the apparent biochemical mechanisms underlying glycolysis activation and OxPhos downregulation in HeLa-M cells.


Assuntos
Glicólise , Mutação , Fosforilação Oxidativa , Proteína Supressora de Tumor p53/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo , Proliferação de Células , Feminino , Células HeLa , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Biogênese de Organelas , Hipóxia Tumoral , Microambiente Tumoral , Proteína Supressora de Tumor p53/metabolismo , Neoplasias do Colo do Útero/patologia
9.
Apoptosis ; 22(1): 27-40, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27766434

RESUMO

The E6 oncoprotein can interfere with the ability of infected cells to undergo programmed cell death through the proteolytic degradation of proapoptotic proteins such as p53, employing the proteasome pathway. Therefore, inactivation of the proteasome through MG132 should restore the activity of several proapoptotic proteins. We investigated whether in HPV16 E6-expressing keratinocytes (KE6 cells), the restoration of p53 levels mediated by MG132 and/or activation of the CD95 pathway through apoptosis antigen-1 (APO-1) antibody are responsible for the induction of apoptosis. We found that KE6 cells underwent apoptosis mainly after incubation for 24 h with MG132 alone or APO-1 plus MG132. Both treatments activated the extrinsic and intrinsic apoptosis pathways. Autophagy was also activated, principally by APO-1 plus MG132. Inhibition of E6-mediated p53 proteasomal degradation by MG132 resulted in the elevation of p53 protein levels and its phosphorylation in Ser46 and Ser20; the p53 protein was localized mainly at nucleus after treatment with MG132 or APO-1 plus MG132. In addition, induction of its transcriptional target genes such as p21, Bax and TP53INP was observed 3 and 6 h after treatment. Also, LC3 mRNA was induced after 3 and 6 h, which correlates with lipidation of LC3B protein and induction of autophagy. Finally, using pifithrin alpha we observed a decrease in apoptosis induced by MG132, and by APO-1 plus MG132, suggesting that restoration of APO-1 sensitivity occurs in part through an increase in both the levels and the activity of p53. The use of small molecules to inhibit the proteasome pathway might permit the activation of cell death, providing new opportunities for CC treatment.


Assuntos
Apoptose/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética , Neoplasias do Colo do Útero/genética , Receptor fas/genética , Anticorpos/farmacologia , Autofagia/efeitos dos fármacos , Benzotiazóis/farmacologia , Proteínas de Transporte/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Feminino , Proteínas de Choque Térmico/genética , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/virologia , Leupeptinas/farmacologia , Proteínas Oncogênicas Virais/genética , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Proteínas Repressoras/genética , Tolueno/análogos & derivados , Tolueno/farmacologia , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/virologia , Proteína X Associada a bcl-2/genética , Receptor fas/metabolismo
10.
Biochim Biophys Acta ; 1853(12): 3266-78, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26434996

RESUMO

The role of p53 as modulator of OxPhos and glycolysis was analyzed in HeLa-L (cells containing negligible p53 protein levels) and HeLa-H (p53-overexpressing) human cervix cancer cells under normoxia and hypoxia. In normoxia, functional p53, mitochondrial enzyme contents, mitochondrial electrical potential (ΔΨm) and OxPhos flux increased in HeLa-H vs. HeLa-L cells; whereas their glycolytic enzyme contents and glycolysis flux were unchanged. OxPhos provided more than 70% of the cellular ATP and proliferation was abolished by anti-mitochondrial drugs in HeLa-H cells. In hypoxia, both cell proliferations were suppressed, but HeLa-H cells exhibited a significant decrease in OxPhos protein contents, ΔΨm and OxPhos flux. Although glycolytic function was also diminished vs. HeLa-L cells in hypoxia, glycolysis provided more than 60% of cellular ATP in HeLa-H cells. The energy metabolism phenotype of HeLa-H cells was reverted to that of HeLa-L cells by incubating with pifithrin-α, a p53-inhibitor. In normoxia, the energy metabolism phenotype of breast cancer MCF-7 cells was similar to that of HeLa-H cells, whereas p53shRNAMCF-7 cells resembled the HeLa-L cell phenotype. In hypoxia, autophagy proteins and lysosomes contents increased 2-5 times in HeLa-H cells suggesting mitophagy activation. These results indicated that under normoxia p53 up-regulated OxPhos without affecting glycolysis, whereas under hypoxia, p53 down-regulated both OxPhos (severely) and glycolysis (weakly). These p53 effects appeared mediated by the formation of p53-HIF-1α complexes. Therefore, p53 exerts a dual and contrasting regulatory role on cancer energy metabolism, depending on the O2level.


Assuntos
Neoplasias da Mama/metabolismo , Metabolismo Energético , Proteína Supressora de Tumor p53/fisiologia , Neoplasias do Colo do Útero/metabolismo , Neoplasias da Mama/patologia , Divisão Celular , Hipóxia Celular , Feminino , Células HeLa , Humanos , Células MCF-7 , Neoplasias do Colo do Útero/patologia
11.
Mol Cell Biochem ; 408(1-2): 261-72, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26173416

RESUMO

Persistent infection with high-risk human papillomaviruses is the main etiological factor in cervical cancer (CC). The human papillomavirus type 16 (HPV16) E7 oncoprotein alters several cellular processes, regulating the expression of many genes in order to avoid cell cycle control. Retinoic acid receptor beta (RARB) blocks cell growth, inducing differentiation and apoptosis. This tumor suppressor gene is gradually silenced in late passages of foreskin keratinocytes immortalized with HPV16 and in various tumors, including CC, mainly by epigenetic modifications. We investigated the effect of E7 oncoprotein on RARB gene expression. We found that HPV16 E7 increases RARB mRNA and RAR-beta protein expression both in vitro and in the cervix of young K14E7 transgenic mice. In E7-expressing cells, RARB overexpression is further increased in the presence of the tumor suppressor p53 (TP53) R273C mutant. This effect does not change when either C33-A or E7-expressing C33-A cell line is treated with Trichostatin A, suggesting that E7 enhances RARB expression independently of histone deacetylases inhibition. These findings indicate that RARB overexpression is part of the early molecular events induced by the E7 oncoprotein.


Assuntos
Proteínas E7 de Papillomavirus/metabolismo , Infecções por Papillomavirus/metabolismo , Receptores do Ácido Retinoico/genética , Receptores do Ácido Retinoico/metabolismo , Regulação para Cima , Neoplasias do Colo do Útero/virologia , Animais , Linhagem Celular Tumoral , Feminino , Células HeLa , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Humanos , Ácidos Hidroxâmicos/farmacologia , Camundongos , Camundongos Transgênicos , Infecções por Papillomavirus/genética , Proteína Supressora de Tumor p53/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo
12.
Sensors (Basel) ; 15(8): 19124-39, 2015 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-26251906

RESUMO

This paper presents preliminary polarization measurements and systematic-error characterization of the Thirty Gigahertz Instrument receiver developed for the QUIJOTE experiment. The instrument has been designed to measure the polarization of Cosmic Microwave Background radiation from the sky, obtaining the Q, U, and I Stokes parameters of the incoming signal simultaneously. Two kinds of linearly polarized input signals have been used as excitations in the polarimeter measurement tests in the laboratory; these show consistent results in terms of the Stokes parameters obtained. A measurement-based systematic-error characterization technique has been used in order to determine the possible sources of instrumental errors and to assist in the polarimeter calibration process.

13.
Oncol Lett ; 28(6): 577, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39397804

RESUMO

Lin28A is an oncoprotein overexpressed in several cancer types such as testicular, ovarian, colon, breast and lung cancers. As a pluripotency factor that promotes tumorigenesis, Lin28A is associated with more undifferentiated and aggressive tumors phenotypes. Moreover, Lin28A is a highly stable protein that is difficult to downregulate. The compound resveratrol (RSV) has anticancer effects. The present study aimed to elucidate the mechanisms underlying the downregulation of Lin28A protein expression by RSV in the NCCIT cell line. NCCIT cells were treated with different concentrations of RSV to investigate its effects on Lin28A expression. The mRNA expression levels of Lin28A and ubiquitin-specific protease 28 (USP28) were assessed using reverse transcription-quantitative PCR. Western blot analysis was employed to evaluate the protein levels of Lin28A, USP28 and phosphorylated Lin28A. In addition, in some experiments, cells were treated with a MAPK/ERK pathway inhibitor, and other experiments involved transfecting cells with small interfering RNAs targeting USP28. The results demonstrated that RSV significantly reduced Lin28A expression by destabilizing the protein; this effect was mediated by the ability of RSV to suppress the expression of USP28, a deubiquitinase that normally protects Lin28A from ubiquitination and degradation. Additionally, RSV inhibited phosphorylation of Lin28A via the MAPK/ERK pathway; this phosphorylation event has previously been shown to enhance the stability of Lin28A by increasing its half-life. This resulted in Lin28A degradation through the proteasomal pathway in NCCIT cells. The results provide further evidence of the anticancer activity of RSV, and identified Lin28A and USP28 as promising therapeutic targets. As a stable oncoprotein, downregulating Lin28A expression is challenging. However, the present study demonstrated that RSV can overcome this hurdle by inhibiting USP28 expression and MAPK/ERK signaling to promote Lin28A degradation. Furthermore, elucidating these mechanisms provides avenues for developing targeted cancer therapies.

14.
FEBS Lett ; 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39152528

RESUMO

Lin28A and Lin28B are paralogous RNA-binding proteins that play fundamental roles in development and cancer by regulating the microRNA family of tumor suppressor Let-7. Although Lin28A and Lin28B share some functional similarities with Let-7 inhibitors, they also have distinct expression patterns and biological functions. Increasing evidence indicates that Lin28A and Lin28B differentially impact cancer stem cell properties, epithelial-mesenchymal transition, metabolic reprogramming, and other hallmarks of cancer. Therefore, it is important to understand the overexpression of Lin28A and Lin28B paralogs in specific cancer contexts. In this review, we summarize the main similarities and differences between Lin28A and Lin28B, their implications in different cellular processes, and their role in different types of cancer. In addition, we provide evidence of other specific targets of each lin28 paralog, as well as the lncRNAs and miRNAs that promote or inhibit its expression, and how this impacts cancer development and progression.

15.
BMC Infect Dis ; 13: 20, 2013 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-23327529

RESUMO

BACKGROUND: In April 2009, public health surveillance detected an increased number of influenza-like illnesses in Mexico City's hospitals. The etiological agent was subsequently determined to be a spread of a worldwide novel influenza A (H1N1) triple reassortant. The purpose of the present study was to demonstrate that molecular detection of pandemic influenza A (H1N1) 2009 strains is possible in archival material such as paraffin-embedded lung samples. METHODS: In order to detect A (H1N1) virus sequences in archived biological samples, eight paraffin-embedded lung samples from patients who died of pneumonia and respiratory failure were tested for influenza A (H1N1) Neuraminidase (NA) RNA using in situ RT-PCR. RESULTS: We detected NA transcripts in 100% of the previously diagnosed A (H1N1)-positive samples as a cytoplasmic signal. No expression was detected by in situ RT-PCR in two Influenza-like Illness A (H1N1)-negative patients using standard protocols nor in a non-related cervical cell line. In situ relative transcription levels correlated with those obtained when in vitro RT-PCR assays were performed. Partial sequences of the NA gene from A (H1N1)-positive patients were obtained by the in situ RT-PCR-sequencing method. Sequence analysis showed 98% similarity with influenza viruses reported previously in other places. CONCLUSIONS: We have successfully amplified specific influenza A (H1N1) NA sequences using stored clinical material; results suggest that this strategy could be useful when clinical RNA samples are quantity limited, or when poor quality is obtained. Here, we provide a very sensitive method that specifically detects the neuraminidase viral RNA in lung samples from patients who died from pneumonia caused by Influenza A (H1N1) outbreak in Mexico City.


Assuntos
Vírus da Influenza A Subtipo H1N1/genética , Influenza Humana/diagnóstico , Influenza Humana/epidemiologia , Neuraminidase/genética , Pandemias , Autopsia , Feminino , Expressão Gênica , História do Século XXI , Humanos , Influenza Humana/história , Pulmão/patologia , Pulmão/virologia , Masculino , México/epidemiologia , RNA Viral , Análise de Sequência de DNA
16.
Gels ; 9(2)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36826245

RESUMO

A low-cost custom-made pseudo-anthropomorphic lung phantom, offering a model for ultrasound-guided interventions, is presented. The phantom is a rectangular solidstructure fabricated with polyvinyl alcohol cryogel (PVA-C) and cellulose to mimic the healthy parenchyma. The pathologies of interest were embedded as inclusions containing gaseous, liquid, or solid materials. The ribs were 3D-printed using polyethylene terephthalate, and the pleura was made of a bidimensional reticle based on PVA-C. The healthy and pathological tissues were mimicked to display acoustic and echoic properties similar to that of soft tissues. Theflexible fabrication process facilitated the modification of the physical and acoustic properties of the phantom. The phantom's manufacture offers flexibility regarding the number, shape, location, and composition of the inclusions and the insertion of ribs and pleura. In-plane and out-of-plane needle insertions, fine needle aspiration, and core needle biopsy were performed under ultrasound image guidance. The mimicked tissues displayed a resistance and recoil effect typically encountered in a real scenario for a pneumothorax, abscesses, and neoplasms. The presented phantom accurately replicated thoracic tissues (lung, ribs, and pleura) and associated pathologies providing a useful tool for training ultrasound-guided procedures.

17.
Biosensors (Basel) ; 13(1)2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36671860

RESUMO

The analysis of near-field radiometry is described for characterizing the internal temperature of biological tissues, for which a system based on multifrequency pseudo-correlation-type radiometers is proposed. The approach consists of a new topology with multiple output devices that enables real-time calibration and performance assessment, recalibrating the receiver through simultaneous measurable outputs. Experimental characterization of the prototypes includes a well-defined calibration procedure, which is described and demonstrated, as well as DC conversion from the microwave input power. Regarding performance, high sensitivity is provided in all the bands with noise temperatures around 100 K, reducing the impact of the receiver on the measurements and improving its sensitivity. Calibrated temperature retrievals exhibit outstanding results for several noise sources, for which temperature deviations are lower than 0.1% with regard to the expected temperature. Furthermore, a temperature recovery test for biological tissues, such as a human forearm, provides temperature values on the order of 310 K. In summary, the radiometers design, calibration method and temperature retrieval demonstrated significant results in all bands, validating their use for biomedical applications.


Assuntos
Micro-Ondas , Radiometria , Humanos , Temperatura , Radiometria/métodos , Temperatura Corporal
18.
Pathogens ; 11(5)2022 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-35631072

RESUMO

There is an urgent need for an oral drug for the treatment of mild to moderate outpatient SARS-CoV-2. Our preclinical and clinical study's aim was to determine the safety and preliminary efficacy of oral TQ Formula (TQF), in the treatment of outpatient SARS-CoV-2. In a double-blind, placebo-controlled phase 2 trial, we randomly assigned (1:1 ratio) non-hospitalized, adult (>18 years), symptomatic SARS-CoV-2 patients to receive oral TQF or placebo. The primary endpoints were safety and the median time-to-sustained-clinical-response (SCR). SCR was 6 days in the TQF arm vs. 8 days in the placebo arm (p = 0.77), and 5 days in the TQF arm vs. 7.5 days in the placebo arm in the high-risk cohort, HR 1.55 (95% CI: 0.70, 3.43, p = 0.25). No significant difference was found in the rate of AEs (p = 0.16). TQF led to a significantly faster decline in the total symptom burden (TSB) (p < 0.001), and a significant increase in cytotoxic CD8+ (p = 0.042) and helper CD4+ (p = 0.042) central memory T lymphocytes. TQF exhibited an in vitro inhibitory effect on the entry of five SARS-CoV-2 variants. TQF was well-tolerated. While the median time-to-SCR did not reach statistical significance; it was shorter in the TQF arm and preclinical/clinical signals of TQF activity across multiple endpoints were significant. Therefore, a confirmatory study is planned.

19.
Discov Oncol ; 13(1): 28, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35445848

RESUMO

Mexico City has one of the highest incidences of acute lymphoblastic leukemia (ALL) globally, with patients showing low survival, and high relapse rates. To gain more insight into the molecular features of B-ALL in Mexican children, we isolated CD10 + /CD19 + precursor B lymphoblasts from four bone marrow and nine peripheral blood samples of B-ALL patients using a fluorescence-activated cell sorting protocol. The global gene expression profile (BM vs PB) revealed 136 differentially expressed genes; 62 were upregulated (45.6%) and 74 were downregulated (54.4%). Pearson's correlation coefficient was calculated to determine the similarity between pre-B lymphoblast populations. We selected 26 highly significant genes and validated 21 by RT-qPCR (CNN3, STON2, CALN1, RUNX2, GADD45A, CDC45, CDC20, PLK1, AIDA, HCK, LY86, GPR65, PIK3CG, LILRB2, IL7R, TCL1A, DOCK1, HIST1H3G, PTPN14, CD72, and NT5E). The gene set enrichment analysis of the total expression matrix and the ingenuity pathway analysis of the 136 differentially expressed genes showed that the cell cycle was altered in the bone marrow with four overexpressed genes (PLK1, CDC20, CDC45, and GADD45A) and a low expression of IL7R and PIK3CG, which are involved in B cell differentiation. A comparative bioinformatics analysis of 15 bone marrow and 10 peripheral blood samples from Hispanic B-ALL patients collected by the TARGET program, corroborated the genes observed, except for PIK3CG. We conclude the Mexican and the Hispanic B-ALL patients studied present common driver alterations and histotype-specific mutations that could facilitate risk stratification and diagnostic accuracy and serve as potential therapeutic targets.

20.
J Physiol Biochem ; 77(4): 547-555, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33937961

RESUMO

The high-risk human papillomavirus (HR-HPV) E7 oncoprotein appears to be a major determinant for cell immortalization and transformation altering critical processes such as cell proliferation, apoptosis, and immune response. This oncoprotein plays an essential role in cervical carcinogenesis, but other cofactors such as long-term use of hormonal contraceptives are necessary to modulate the risk of cervical cancer (CC). The role of HR-HPVs in the alteration of microRNA (miRNA) levels in persistent viral infections currently remains unclear. The aim of this study was to evaluate the miR-34a and miR-15b expression levels in the murine HPV16K14E7 (K14E7) transgenic model after chronic estrogen (E2) treatment and their involvement in CC. Interestingly, results showed that, although miR-34a expression is elevated by the HPVE7 oncogene, this expression was downregulated in the presence of both the E7 oncoprotein and chronic E2 in cervical carcinoma. On the other hand, miR-15b expression was upregulated along cervical carcinogenesis mainly by the effect of E2. These different changes in the expression levels of miR-34a and miR-15b along cervical carcinogenesis conduced to low apoptosis levels, high cell proliferation and finally, to cancerous cervical tissue development. In this work, we also determined the relative mRNA expression of Cyclin E2 (Ccne2), Cyclin A2 (Ccna2), and B cell lymphoma 2 (Bcl-2) (target genes of miR-34a and miR-15b); Sirtuin 1 (Sirt1), Cmyc, and Bax (miR-34a target genes); and p21/WAF1 (mir15b target gene) and the H-ras oncogene. Given the modifications in the expression levels of miR-34a and miR-15b during the development of cervical cancer, it will be useful to carry out further investigation to confirm them as molecular biomarkers of cancer.


Assuntos
MicroRNAs , Neoplasias do Colo do Útero , Animais , Proliferação de Células , Colo do Útero , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , MicroRNAs/genética , Neoplasias do Colo do Útero/genética
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