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1.
J Biochem Mol Toxicol ; 38(11): e70044, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39503181

RESUMO

Natural killer (NK) cells are vital innate immune cells that play a crucial role in cancer therapy. They are targeted by therapies designed to modulate, retain, and enhance their antitumor function in vivo. In addition to whole-cell therapy, NK cell-derived exosomes (NDEs) offer high immune safety and are easily subject to chemical, biological, and immunological modifications. This makes them suitable for use in combination with various current cancer therapies to enhance efficacy, treatment outcomes, and reduce side effects in vivo. This review aims to outline summarizes the antitumor potential of NK cells, as well as the current challenges and opportunities in NK cell-based immunotherapies such as allogeneic and autologous NK cell transplantation, CAR NK cell therapy, and the use of cytokines and monoclonal antibodies. The review also explores the dual regulatory effects of tumor exosomes on NK cells, and highlights the potential of NDEs, either alone or in combination with other antitumor therapies, to reprogram the immunosuppressive tumor microenvironment and expedite the therapeutic effects of cancer immunotherapy in future clinical research.


Assuntos
Exossomos , Imunoterapia , Células Matadoras Naturais , Neoplasias , Células Matadoras Naturais/imunologia , Humanos , Neoplasias/imunologia , Neoplasias/terapia , Imunoterapia/métodos , Exossomos/imunologia , Exossomos/transplante , Animais , Microambiente Tumoral/imunologia
2.
Sci Rep ; 14(1): 26651, 2024 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-39496675

RESUMO

Key frame extraction is very important in video summarization and content-based video analysis to address the problem of data redundancy in a video. Key frame extraction enables quick navigation and expert video arrangement in many applications. The visually impaired can benefit from the use of key frame extraction for rapid object recognition and tracking. Most key frame extraction techniques consider only a single visual feature instead of multiple features or full pictorial information of the video. This study proposes a key frame extraction method from a video that (i) first removes insignificant frames by pre-processing, (ii) second, four visual and structural feature differences among the consecutive frames are extracted and aggregated to identify informative frames, (iii) third, to cluster the obtained frames, a hybrid FCM-AHA method is proposed by combining Fuzzy C-means(FCM) with artificial hummingbird optimization algorithm (AHA) to circumvent the local minima trapping problem of FCM, and finally, from each cluster, the two frames having greatest Euclidean distance from all the other frames within a cluster is selected as key frames to remove redundant frames. Experimental results on the Open video and YouTube datasets show that the suggested method outperforms state-of-the-art methods both in terms of subjective qualitative analysis and objective quantitative evaluation, e.g., Precision, Recall, and F-score. Further, results are also taken on real video to demonstrate its applicability in real-life applications.

3.
RSC Adv ; 14(33): 23592-23605, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39077319

RESUMO

This study undertakes a comparative analysis of the structural, morphological, electrical, and magnetic characteristics of Fe-doped LaMnO3 ceramics. The solid-state reaction method was used to prepare Fe-doped LaMnO3 at different concentrations (0.00 ≤ x ≤ 1.00) and has been characterized using X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), Field emission scanning electron microscopy (FE-SEM), energy-dispersive spectroscopy (EDS), and vibrating sample magnetometry (VSM). The structural transformation from rhombohedral to orthorhombic with Fe-doping is demonstrated by Rietveld's refined XRD patterns. The positive slope in Williamsons-Hall's (W-H) plots confirms the presence of tensile strain with increasing average crystallite size. Quasi-spherical morphology of all the compositions with similar uniformity was confirmed by FESEM images. The chemical distribution of all the elements has been identified by EDS mapping images. Normal dielectric dispersion behaviour of all the samples with NTCR response is confirmed by dielectric and impedance analysis respectively. Increasing lattice volume with Fe-concentration results is increasing E a. The presence of antiferromagnetic ordering, in addition to weak ferromagnetic ordering, is indicated by the unsaturated magnetization even up to a high external field. The decrease in M S and increase in H C values due to Fe-doping reflect the influence of particle size on various magnetic parameters.

4.
Artigo em Inglês | MEDLINE | ID: mdl-36360827

RESUMO

Gestational diabetes mellitus (GDM) during pregnancy is a marker for future type 2 diabetes mellitus (T2DM); therefore, a meticulous follow-up after delivery can help identify women at risk for T2DM. In a cohort of 5504 pregnant women, the postpartum follow-up of all 1043 women with GDM for hyperglycemia in a multi-ethnic, high-risk Arab population was investigated. The prevalence of GDM was 18.9%. A total of 265 (25.4%) women returned for an oral glucose tolerance test (OGTT) 4-6 weeks after delivery, with more South Asian than Arab women (p < 0.01). The other factors associated with return were (a) family history of T2DM, (b) lower basic metabolic index, (c) higher abortions and (d) lower gravida (p < 0.05), all with minimal effect. An abnormal postpartum OGTT was statistically associated with previous GDM history and hypoglycemic drug treatment, although these effects were small. Overall, the follow-up of women with GDM postpartum was dismal, ethnicity being the major factor influencing return. Urgent public measures are needed to educate women with GDM about follow-up highlighting (a) risk awareness for T2DM and (b) a healthy lifestyle after childbirth-if we are to turn the tide on the epidemic of T2DM plaguing the Arab world.


Assuntos
Diabetes Mellitus Tipo 2 , Diabetes Gestacional , Intolerância à Glucose , Feminino , Gravidez , Humanos , Masculino , Diabetes Gestacional/diagnóstico , Diabetes Gestacional/epidemiologia , Diabetes Gestacional/terapia , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Etnicidade , Teste de Tolerância a Glucose , Intolerância à Glucose/epidemiologia , Período Pós-Parto , Fatores de Risco , Glicemia/metabolismo
5.
Sci Rep ; 11(1): 17889, 2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34504239

RESUMO

Sn-doped BaTi4O9 (BT4) dielectric ceramics were prepared by a mixed oxide route. Preliminary X-ray diffraction (XRD) structural study shows that the ceramic samples have orthorhombic symmetry with space group (Pnmm). Scanning electron microscopy (SEM) shows that the grain size of the samples decreases with an increase in Sn4+ content. The presence of the metal oxide efficient group was revealed by Fourier transform infrared (FTIR) spectroscopy. The photoluminescence spectra of the ceramic samples reported red color ~ 603, 604, 606.5 and 605 nm with excitation energy ~ 2.06, 2.05, 2.04 and 2.05 eV for Sn4+ content with x = 0.0, 0.3, 0.5, and 0.7, respectively. The microwave dielectric properties of these ceramic samples were investigated by an impedance analyzer. The excellent microwave dielectric properties i.e. high dielectric constant (εr = 57.29), high-quality factor (Qf = 11,852), or low-dielectric loss (3.007) has been observed.

6.
J Xray Sci Technol ; 26(2): 209-225, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29154313

RESUMO

BACKGROUND: Since breast ultrasound images are of low contrast, contain inherent noise and shadowing effect due to its imaging process, segmentation of breast tumors depicting ultrasound image is a challenging task. Thus, a robust breast ultrasound image segmentation technique is inevitable. OBJECTIVE: To develop an automatic lesion segmentation technique for breast ultrasound images. METHODS: First, the technique automatically detects the suspicious tumor region of interest and discards the unwanted complex background regions. Next, based on the concept of information gain, the technique applies an existing neutrosophic clustering method to the detected region to segment the desired tumor area. The proposed technique computes information gain values from the local neighbourhood of each pixel, which is further used to update the membership values and the cluster centers for the neutrosophic clustering process. Integrating the concept of entropy and neutrosophic logic features into the technique enabled to generate better segmentation results. RESULTS: Results of proposed method were compared both qualitatively and quantitatively with fuzzy c-means, neutrosophic c-means and neutrosophic ℓ-means clustering methods. It was observed that the proposed method outperformed the other three methods and yielded the best Mean (TP: 94.72, FP: 5.85, SI: 93.75, HD: 8.2, AMED: 2.4) and Standard deviation (TP: 3.2, FP: 3.7, SI: 3.8, HD: 2.6, AMED: 1.3) values for different quality metrics on the current set of breast ultrasound images. CONCLUSION: Study demonstrated that the proposed technique is robust to the shadowing effect and produces more accurate segmentation of the tumor region, which is very similar to that visually segmented by Radiologist.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mama/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Ultrassonografia Mamária/métodos , Adolescente , Adulto , Idoso , Algoritmos , Análise por Conglomerados , Feminino , Lógica Fuzzy , Humanos , Pessoa de Meia-Idade , Adulto Jovem
7.
3 Biotech ; 7(5): 282, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28828289

RESUMO

An efficient, simple and commercially applicable protocol for rapid micropropagation of sugarcane has been designed using variety Co 05011. Pretreatment of shoot tip explants with thidiazuron (TDZ) induced high frequency regeneration of shoot cultures with improved multiplication ratio. The highest frequency (80%) of shoot initiation in explants pretreated with 10 mg/l of TDZ was obtained during the study. Maximum 65% shoot cultures could be established from the explants pretreated with TDZ as compared to minimum 40% establishment in explants without pretreatment. The explants pretreated with 10 mg/l of TDZ required minimum 40 days for the establishment of shoot cultures as compared to untreated explants which required 60 days. The highest average number of shoots per culture (19.1) could be obtained from the explants pretreated with 10 mg/l of TDZ, indicating the highest multiplication ratio (1:6). Highest rooting (over 94%) was obtained in shoots regenerated from pretreated explants on ½ strength MS medium containing 5.0 mg/l of NAA and 50 g/l of sucrose within 15 days. Higher number of tillers/clump (15.3) could be counted in plants regenerated from pretreated explants than untreated ones (10.9 tillers/clump) in field condition, three months after transplantation. Molecular analysis using RAPD and DAMD markers suggested that the pretreatment of explants with TDZ did not adversely affect the genetic stability of regenerated plants and maintained high clonal purity.

8.
BMC Nephrol ; 10: 4, 2009 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-19220921

RESUMO

BACKGROUND: Chronic kidney disease (CKD) is increasingly being recognized as an emerging public health problem in India. However, community based estimates of low glomerular filtration rate (GFR) and proteinuria are few. Validity of traditional serum creatinine based GFR estimating equations in South Asian subjects is also debatable. We intended to estimate and compare the prevalence of low GFR, proteinuria and associated risk factors in North India using Cockcroft-Gault (CG) and Modification of Diet In Renal Disease (MDRD) equation. METHODS: A community based, cross-sectional study involving multistage random cluster sampling was done in Delhi and its surrounding regions. Adults > or = 20 years were surveyed. CG and MDRD equations were used to estimate GFR (eGFR). Low GFR was defined as eGFR < 60 ml/min/1.73 m2. Proteinuria (> or = 1+) was assessed using visually read dipsticks. Odds ratios, crude and adjusted, were calculated to ascertain associations between renal impairment, proteinuria and risk factors. RESULTS: The study population had 3,155 males and 2,097 females. The mean age for low eGFR subjects was 54 years. The unstandardized prevalence of low eGFR was 13.3% by CG equation and 4.2% by MDRD equation. The prevalence estimates of MDRD equation were lower across gender and age groups when compared with CG equation estimates. There was a strong correlation but poor agreement between GFR estimates of two equations. The survey population had a 2.25% prevalence of proteinuria. In a multivariate logistic regression analysis; age above 60 years, female gender, low educational status, increased waist circumference, hypertension and diabetes were associated with low eGFR. Similar factors were also associated with proteinuria. Only 3.3% of subjects with renal impairment were aware of their disease. CONCLUSION: The prevalence of low eGFR in North India is probably higher than previous estimates. There is a significant difference between GFR estimates derived from CG and MDRD equations. These equations may not be useful in epidemiological research. GFR estimating equations validated for South Asian populations are needed before reliable estimates of CKD prevalence can be obtained. Till then, primary prevention and management targeted at CKD risk factors must play a critical role in controlling rising CKD magnitude. Cost-benefit analysis of targeted screening programs is needed.


Assuntos
Algoritmos , Nefropatias/epidemiologia , Proteinúria/epidemiologia , Adulto , Idoso , Consumo de Bebidas Alcoólicas/epidemiologia , Antropometria , Comorbidade , Creatinina/sangue , Estudos Transversais , Países em Desenvolvimento , Diabetes Mellitus/epidemiologia , Taxa de Filtração Glomerular , Humanos , Hipertensão/epidemiologia , Índia/epidemiologia , Nefropatias/diagnóstico , Pessoa de Meia-Idade , Obesidade/epidemiologia , Prevalência , Fatores de Risco , Estudos de Amostragem , Fumar/epidemiologia , Mudança Social
10.
Indian J Public Health ; 51(3): 198-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18229446

RESUMO

The present study was undertaken to determine the seroprevalence of dengue fever and dengue haemorrhagic fever (DHF) in patients attending medical clinics or admitted in ICU with febrile signs and symptoms of heamorrhages. 168 (39.4%) out of 426 samples were tested positive for IgM antibodies. Of the 168 positive cases 159 were detected during the months of October and November 2005. Early detection of DHF/DSS can go a long way in managing these patients and to reduce morbidity and mortality specially in DHF and DSS cases.


Assuntos
Doenças Transmissíveis Emergentes/epidemiologia , Dengue/epidemiologia , Animais , Culicidae , Dengue/diagnóstico , Surtos de Doenças , Humanos , Índia/epidemiologia , Insetos Vetores , Chuva , Estudos Soroepidemiológicos , Clima Tropical
11.
Indian J Pathol Microbiol ; 49(1): 49-50, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16625978

RESUMO

The adherence of pathogenic bacteria to eukaryotic cells plays a central role in their ability to colonize the mucosal epithelial surfaces. The adherence by Y. enterocolitica to the mucosal surface of the gut is the initiating event leading to penetration of mucosa. Adhesion of 10 probable pathogenic and one non-pathogenic isolate was studied using ileum and colon epithelial cells of mouse for 90 minutes. Adhesion study revealed that isolates of Y. enterocolitica had a good adhesive property while non pathogenic showed negligible adherence. All isolates showed better adherence to colon epithelial cells. The organism continued to be excreted in faeces up to 8-10 days after oral feeding. Adhesion positive isolates were found to be virulent when tested in mice for diarrhoea and death. Adhesion was found to be thermoregulated.


Assuntos
Aderência Bacteriana , Colo/microbiologia , Íleo/microbiologia , Mucosa Intestinal/microbiologia , Yersinia enterocolitica/patogenicidade , Animais , Células Cultivadas , Diarreia/microbiologia , Células Epiteliais/microbiologia , Fezes/microbiologia , Camundongos , Análise de Sobrevida , Virulência , Yersiniose/microbiologia
13.
Indian J Pathol Microbiol ; 47(4): 559-64, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16295398

RESUMO

Yersinia enterocolitica is an enteric bacterium and infections by this organism are mostly foodborne. It has been implicated to cause enterocolitis, terminal ilitis. diarrhoea, mesenteric lymphadenitis and arthritis in man. Due to paucity of information regarding histopathological and specially ultrastructural alterations in tissues affected, this study was planned with mice as the experimental model. Nine pathogenic Y.enterocoliticaisolates were used to infect 80 albino mice by oral and intraperitoneal route. Pathological alterations were studied by light and electron microscopy. Histopathological examination of intestines showed severe edema, purulent enteritis, goblet cell hyperplasia infiltration of mononuclear cells, thickening of mucosa and necrosis of the tips of villi. Liver showed congestion, hepatocellular degeneration and necrosis, atrophy of hepatocytes and microabcesses. The lungs revealed congestion, edema, haemorrhage and purulent ronchopneumonia, while kidneys showed mild necrotic changes and bacterial emboli in glomeruli. Ultrastructural changes were indicative of mitochondrial degeneration and their loss in kidneys, membranous degeneration with formation of myelin figures in lungs and disorganization, disruption and bleb formation of microvilli in intestines. Y.enterocolitica caused significant histopathological and ultrastructural alterations in experimentally infected mice. Variation in pathogenicity of different strains of Y.enterocolitica was also observed.


Assuntos
Yersiniose/patologia , Yersinia enterocolitica , Animais , Modelos Animais de Doenças , Humanos , Intestinos/patologia , Rim/patologia , Pulmão/patologia , Camundongos , Microscopia Eletrônica , Virulência , Yersinia enterocolitica/patogenicidade
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