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1.
Pathol Res Pract ; 254: 155083, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38277749

RESUMO

Small extracellular vesicles called exosomes play a crucial part in promoting intercellular communication. They act as intermediaries for the exchange of bioactive chemicals between cells, released into the extracellular milieu by a variety of cell types. Within the context of cancer progression, metastasis is a complex process that plays a significant role in the spread of malignant cells from their main site of origin to distant anatomical locations. This complex process plays a key role in the domain of cancer-related deaths. In summary, the trajectory of current research in the field of exosome-mediated metastasis is characterized by its unrelenting quest for more profound understanding of the molecular nuances, the development of innovative diagnostic tools and therapeutic approaches, and the unwavering dedication to transforming these discoveries into revolutionary clinical applications. This unrelenting pursuit represents a shared desire to improve the prognosis for individuals suffering from metastatic cancer and to nudge the treatment paradigm in the direction of more effective and customized interventions.


Assuntos
Exossomos , Vesículas Extracelulares , Neoplasias , Humanos , Exossomos/metabolismo , Neoplasias/patologia , Vesículas Extracelulares/metabolismo , Comunicação Celular , Biologia Molecular , Microambiente Tumoral
2.
AoB Plants ; 15(6): plad074, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38130422

RESUMO

High-throughput sequencing of herbarium specimens' DNA with short-read platforms has helped explore many biological questions. Here, for the first time, we investigate the potential of using herbarium specimens as a resource for long-read DNA sequencing technologies. We use target capture of 48 low-copy nuclear loci in 12 herbarium specimens of Silene as a basis for long-read sequencing using SMRT PacBio Sequel. The samples were collected between 1932 and 2019. A simple optimization of size selection protocol enabled the retrieval of both long DNA fragments (>1 kb) and long on-target reads for nine of them. The limited sampling size does not enable statistical evaluation of the influence of specimen age to the DNA fragmentation, but our results confirm that younger samples, that is, collected after 1990, are less fragmented and have better sequencing success than specimens collected before this date. Specimens collected between 1990 and 2019 yield between 167 and 3403 on-target reads > 1 kb. They enabled recovering between 34 loci and 48 (i.e. all loci recovered). Three samples from specimens collected before 1990 did not yield on-target reads > 1 kb. The four other samples collected before this date yielded up to 144 reads and recovered up to 25 loci. Young herbarium specimens seem promising for long-read sequencing. However, older ones have partly failed. Further exploration would be necessary to statistically test and understand the potential of older material in the quest for long reads. We would encourage greatly expanding the sampling size and comparing different taxonomic groups.

3.
Sensors (Basel) ; 23(18)2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37765849

RESUMO

Hand gesture recognition is a vital means of communication to convey information between humans and machines. We propose a novel model for hand gesture recognition based on computer vision methods and compare results based on images with complex scenes. While extracting skin color information is an efficient method to determine hand regions, complicated image backgrounds adversely affect recognizing the exact area of the hand shape. Some valuable features like saliency maps, histogram of oriented gradients (HOG), Canny edge detection, and skin color help us maximize the accuracy of hand shape recognition. Considering these features, we proposed an efficient hand posture detection model that improves the test accuracy results to over 99% on the NUS Hand Posture Dataset II and more than 97% on the hand gesture dataset with different challenging backgrounds. In addition, we added noise to around 60% of our datasets. Replicating our experiment, we achieved more than 98% and nearly 97% accuracy on NUS and hand gesture datasets, respectively. Experiments illustrate that the saliency method with HOG has stable performance for a wide range of images with complex backgrounds having varied hand colors and sizes.

4.
Prep Biochem Biotechnol ; 52(10): 1190-1201, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35234088

RESUMO

The main purpose of the present study is to introduce the biochemical characteristics of the industrial valuable thermostable pullulan degrading enzyme from Desulfurococcus mucosus DSM2162. Recombinant protein was purified by a combination of thermal treatment and affinity chromatography, with a yield of 15.94% and 7.69-fold purity. Purified enzyme showed the molecular mass of 55,787 Da with optimum activity at 70 °C and a broad range of pH (5.0-9.0) with kcat of 2150 min-1 and Km of 6.55 mg.mL-1, when using starch as substrate. The enzyme activity assay on various polysaccharide substrates revealed the substrate preference of pullulan > amylopectin > ß cyclodextrin > starch > glycogen; therefore, it classified as a neopullulanase. The neopullulanase structural analysis by spectrofluorometer, FT-IR, and circular dichroism spectroscopy indicated the corporation of α-helix (47.3%) and ß-sheet (31.6%) in its secondary structure. The melting temperature and specific heat capacity calculations using differential scanning calorimetry confirmed its extreme thermal stability. Further, salt-elevated concentrations resulted in oligomeric state dominancy without any significant influence on the starch-degrading ability. The newly cloned archaeal neopullulanase was with broad activity on polysaccharide substrates, with thermal and salt stability. Thus, the Desulfurococcus mucosus DSM2162 neopullulanase can be introduced as a good candidate to be used in carbohydrate industry.


Assuntos
Archaea , Desulfurococcaceae , Archaea/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Especificidade por Substrato , Glicosídeo Hidrolases/metabolismo , Amido/metabolismo , Polissacarídeos , Desulfurococcaceae/genética , Desulfurococcaceae/metabolismo , Clonagem Molecular , Concentração de Íons de Hidrogênio , Estabilidade Enzimática
5.
Immunol Cell Biol ; 99(8): 814-832, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33988889

RESUMO

The mechanistic/mammalian target of rapamycin (mTOR) is considered to be an atypical protein kinase that plays a critical role in integrating different cellular and environmental inputs in the form of growth factors, nutrients and energy and, subsequently, in regulating different cellular events, including cell metabolism, survival, homeostasis, growth and cellular differentiation. Immunologically, mTOR is a critical regulator of immune function through integrating numerous signals from the immune microenvironment, which coordinates the functions of immune cells and T cell fate decisions. The crucial role of mTOR in immune responses has been lately even more appreciated. MicroRNAs (miRNAs) are endogenous, small, noncoding single-stranded RNAs that act as molecular regulators involved in multiple processes during immune cells development, homeostasis, activation and effector polarization. Several studies have recently indicated that a range of miRNAs are involved in regulating the phosphoinositide 3-kinase/protein kinase B/mTOR (PI3K/AKT/mTOR) signaling pathway by targeting multiple components of this signaling pathway and modulating the expression and function of these targets. Current evidence has revealed the interplay between miRNAs and the mTOR pathway circuits in various immune cell types. The expression of individual miRNA can affect the function of mTOR signaling to determine the cell fate decisions in immune responses through coordinating immune signaling and cell metabolism. Dysregulation of the mTOR pathway/miRNAs crosstalk has been reported in cancers and various immune-related diseases. Thus, expression profiles of dysregulated miRNAs could influence the mTOR pathway, resulting in the promotion of aberrant immunity. This review summarizes the latest information regarding the reciprocal role of the mTOR signaling pathway and miRNAs in orchestrating immune responses.


Assuntos
MicroRNAs , Diferenciação Celular , MicroRNAs/genética , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
6.
Ann Diagn Pathol ; 49: 151654, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33130384

RESUMO

Osteosarcoma, a bone cancer usually seen in children and young adults, is generally a high-grade malignancy presented by extreme metastases to the lungs. Osteosarcoma has a tendency for appearing in bones with rapid growth rate. The etiology of osteosarcoma is multifaceted and poorly understood. A molecular consideration of this disease will lead to a directed tumor treatment. The present treatment for osteosarcoma comprises of an arrangement of systemic chemotherapy and wide surgical resection. Survival rate is increased by the progress of destructive systemic chemotherapies. So, the development of new treatment approaches for metastatic osteosarcoma is essential. Immunomodulation has been used in clinical settings. Through targeting surface antigens expressed on tumor cells, particular antibodies and exploitation of cellular immunotherapy against sarcomas have been confirmed to be effective as cancer therapeutics. In this article, we have reviewed epidemiology, etiology, pathogenesis, diagnosis, and treatment of osteosarcoma and we have focused on different methods of immunotherapy including vaccines, cell-based immunotherapy, cytokines, and monoclonal antibodies.


Assuntos
Neoplasias Ósseas/terapia , Osteossarcoma/terapia , Humanos , Imunoterapia/métodos
7.
PhytoKeys ; 159: 1-34, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32973386

RESUMO

A putatively monophyletic group of annual Silene species is revised taxonomically and described as the new section S. sect. Arenosae. The species of this section were previously treated as a part of a widely circumscribed and polyphyletic S. sect. Rigidulae. Silene sect. Arenosae as circumscribed here consists of nine species. Members of the section show a predominantly E Mediterranean to SW Asian distribution pattern from Turkey southward to Egypt and eastward to Iran and Pakistan, although most of the species have a limited distribution range. The species of S. sect. Arenosae are characterized by narrowly lanceolate calyx teeth, which are often highly polymorphic, and lanceolate to oblanceolate (non-spathulate) basal leaves. The provided taxonomic revision is based on morphological characters and supported by phylogenetic analyses of two nuclear loci (nrITS and an intron of the RPB2 gene) and one chloroplast locus (the intron of the rps16 gene). The species descriptions are formalized using a novel implementation of the Prometheus Description Model.

8.
Med J Islam Repub Iran ; 33: 20, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31380310

RESUMO

Background: Accidental exposure to sharp instruments is an important problem for health care students. Thus, the aim of this study was to determine the rate of immunity in health care students 2 decades after national neonatal hepatitis B (HB) vaccination. Methods: All junior students attending medicine, nursing and midwifery schools were screened for anti-HBs. One dose of hepatitis B vaccine was offered to all participants who did not have antibodies to HB surface antigen (anti-HBs) of > 10 IU/L; then, they were tested for anti-HBs after a month. The participants were classified into 3 groups: postboosting nonimmune, postboosting immune, and preboosting immune. Chi square test and ANOVA were used for data analysis. Results: In the first step, 65.20% of participants did not show immunity, but after receiving a booster dose, only 6.0% remained nonimmune. The mean age of nonimmune students was significantly higher than that of students who had postboosting immune and preboosting immune status (p=0.001 and 0.002, respectively). Also, the mean injection time from last shot was higher in postboosting immune group compared to preboosting immune group (p<0.001). Also, prebooster anti-HBs level was significantly different among participants with suboptimal response and those who developed anamnestic response, indicating preserved immune memory (p=0.001). Conclusion: High anamnestic response to HBV booster dose indicates sufficient immunity to HBV in the majority of health care students. However, identifying students who cannot respond to a booster dose of vaccine seems to be necessary at the beginning of health care courses.

9.
Artif Cells Nanomed Biotechnol ; 47(1): 1295-1311, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30033768

RESUMO

The aim of this study was to optimize the cationic PEGylated niosome-containing anti-cancer drugs and siRNA to enhance the therapeutic response. Therefore, various surfactant-based (tween-60) vesicles of doxorubicin (DOX; a chemotherapeutic drug) and quercetin (QC; a chemosensitizer) were prepared. To load siRNA on niosomes, 1, 2-dioleoyl-3-trimethylammonium-propane (DOTAP) was used as a cationic lipid. The optimum formulation containing tween-60:cholesterol:DPPC:DOTAP:DSPE-PEG2000 at 49.5:5.5:15:25:5 demonstrated that the vesicle size and zeta potential were 52.8 ± 2.7 nm and +27.4 ± 2.3 mV, respectively. Entrapment efficiency (EE%) for DOX and QC was 86.4 ± 2.1% and 94.9 ± 3.9%, respectively. Moreover, the drug release during 6 h was 32.1 ± 1.6% and 30.5 ± 1.3% for DOX and QC, respectively denoted on the controlled release. The gel retardation assay demonstrated that siRNA could be successfully loaded into a cationic niosome:siRNA in a weight ratio 40:1. Additionally, noisome-encapsulated drugs had a higher toxicity against cancer cells when compared with un-encapsulated forms and the synergistic effects of co-delivery of siRNA and DOX with QC on gastric, prostate, breast cancer cells as well as human foreskin fibroblast as a normal cell line was shown. The results showed that the co-delivery of drugs and siRNA using cationic PEGylated niosomes exhibited an increased anti-cancer activity against the tumor cell death. It seems that cationic PEGylated niosomes have opened up a new avenue to enrich the armamentarium of therapeutic agents to fight cancer.


Assuntos
Doxorrubicina/química , Doxorrubicina/farmacologia , Polietilenoglicóis/química , Quercetina/química , Quercetina/farmacologia , RNA Interferente Pequeno/química , RNA Interferente Pequeno/genética , Transporte Biológico , Cápsulas , Linhagem Celular Tumoral , Terapia Combinada , Doxorrubicina/administração & dosagem , Liberação Controlada de Fármacos , Ácidos Graxos Monoinsaturados/química , Humanos , Concentração de Íons de Hidrogênio , Lipossomos/química , Compostos de Amônio Quaternário/química , Quercetina/administração & dosagem , RNA Interferente Pequeno/administração & dosagem
10.
J Reprod Med ; 59(11-12): 566-70, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25552129

RESUMO

OBJECTIVE: To determine the curative effect of a repeat uterine evacuation in patients with low-risk gestational trophoblastic neoplasia. STUDY DESIGN: Patients with low-risk gestational trophoblastic neoplasia (GTN)(N=12), diagnosed according to the International Federation of Gynecology and Obstetrics 2002 guidelines, were enrolled in a prospective cohort study. Primary outcomes were need for chemotherapy after second uterine evacuation and number of chemotherapy courses needed to achieve complete remission. RESULTS: Ten patients (83%) did not require chemotherapy and were cured bya second curettage. Two patients failed to respond to the second curettage and received single-agent chemotherapy with actinomycin-D (1.25 mg/m2 biweekly, slow intravenous administration). Both patients responded to chemotherapy as second-line therapy. A 100% remission rate was achieved, with no recurrence at the 1-year follow-up. One patient (8%) had a uterine perforation. CONCLUSION: Second curettage has a favorable response rate. It seems reasonable to perform a second curettage in patients with low-risk GTN in settings where serum beta-hCG assay follow-up is highly reliable and available. However, its potential complications and inconvenience must be discussed critically with each patient.


Assuntos
Dilatação e Curetagem/métodos , Doença Trofoblástica Gestacional/cirurgia , Neoplasias Uterinas/cirurgia , Útero/cirurgia , Adulto , Estudos de Coortes , Feminino , Humanos , Projetos Piloto , Gravidez , Reoperação , Resultado do Tratamento
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