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1.
BMC Oral Health ; 24(1): 219, 2024 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-38342887

RESUMO

BACKGROUND: This study was conducted to assess the prevalence of dental caries, tobacco usage, and associated risk factors for dental caries in patients who visited a government hospital in Western, Nepal. METHODS: This analytical cross-sectional study was conducted from January to April 2022. Patients above 18 years visiting the dental OPD of a government hospital, and who had provided informed consent were enrolled in the study using a convenience sampling technique. As the study also involved an illiterate population, in that case, informed consent was obtained from their respective legal guardian as well. A pretested standardized, close-ended questionnaire was administered by researchers to gather information regarding the associated risk factors and oral hygiene practices. Clinical examination was done for dental caries according to the criteria by the World Health Organization (WHO) using the "DMFT" index (WHO modification 1987). Bivariate and multivariable logistic regression was done and the odds ratio and p-value was calculated. For all tests, statistical significance was set at p < 0.05. RESULTS: A total of 219 participants completed the study with a mean age of 31.73 ± 12.46. The prevalence of dental caries and tobacco was found to be 80.36% and 5.02% respectively. Participants without health insurance had 2.35 times higher odds of dental caries (95% CI: 1.03-5.36). Not rinsing the mouth after eating sweets was associated with 3.07 times higher odds of dental caries (95% CI: 1.31-7.18). Those who hadn't visited a dentist in the past 12 months had lower odds (0.42; 95% CI: 0.18-0.94). Eating fresh fruit daily showed statistically higher odds (2.70; 95% CI: 1.04-6.99) of dental caries. Non-tobacco users had higher odds (14.19; 2.55-78.99) of dental caries. CONCLUSION: Dental caries is highly prevalent, while tobacco usage is relatively low. Factors associated with dental caries included lack of health insurance coverage, consumption of fruits once daily, recent dental visits within the past year, not rinsing the mouth with water after consuming sweets, and non-tobacco users.


Assuntos
Cárie Dentária , Humanos , Adulto Jovem , Adulto , Cárie Dentária/epidemiologia , Cárie Dentária/etiologia , Estudos Transversais , Nepal/epidemiologia , Índice CPO , Fatores de Risco , Prevalência , Governo , Hospitais , Produtos do Tabaco
2.
Indian J Pediatr ; 91(2): 191-192, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37782391

RESUMO

Perinatal spinal cord injury is a relatively uncommon, but a frequently misdiagnosed disorder. Improvements in obstetric care have certainly led to a decrease in the incidence of birth related spinal cord trauma but unfortunately the incidence of hypoxic-ischemic encephalopathy is still very high. The exact incidence of spinal cord trauma is difficult to determine because the spinal cord is not routinely examined in far and few neonatal autopsies done in India. Here, authors present a neonate who received treatment for birth asphyxia and then had extubation failure which made the clock tick towards cervical cord injury. This baby had a hemorrhagic contusion of cervical spinal cord.


Assuntos
Asfixia Neonatal , Medula Cervical , Hipóxia-Isquemia Encefálica , Traumatismos da Medula Espinal , Recém-Nascido , Gravidez , Feminino , Humanos , Hipóxia-Isquemia Encefálica/complicações , Hipóxia-Isquemia Encefálica/diagnóstico , Medula Cervical/diagnóstico por imagem , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/diagnóstico , Asfixia Neonatal/complicações , Incidência
3.
J Ultrasound Med ; 43(1): 137-150, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37873733

RESUMO

OBJECTIVES: Quantitative ultrasound (QUS) is a noninvasive imaging technique that can be used for assessing response to anticancer treatment. In the present study, tumor cell death response to the ultrasound-stimulated microbubbles (USMB) and hyperthermia (HT) treatment was monitored in vivo using QUS. METHODS: Human breast cancer cell lines (MDA-MB-231) were grown in mice and were treated with HT (10, 30, 50, and 60 minutes) alone, or in combination with USMB. Treatment effects were examined using QUS with a center frequency of 25 MHz (bandwidth range: 16 to 32 MHz). Backscattered radiofrequency (RF) data were acquired from tumors subjected to treatment. Ultrasound parameters such as average acoustic concentration (AAC) and average scatterer diameter (ASD), were estimated 24 hours prior and posttreatment. Additionally, texture features: contrast (CON), correlation (COR), energy (ENE), and homogeneity (HOM) were extracted from QUS parametric maps. All estimated parameters were compared with histopathological findings. RESULTS: The findings of our study demonstrated a significant increase in QUS parameters in both treatment conditions: HT alone (starting from 30 minutes of heat exposure) and combined treatment of HT plus USMB finally reaching a maximum at 50 minutes of heat exposure. Increase in AAC for 50 minutes HT alone and USMB +50 minutes was found to be 5.19 ± 0.417% and 5.91 ± 1.11%, respectively, compared to the control group with AAC value of 1.00 ± 0.44%. Furthermore, between the treatment groups, ΔASD-ENE values for USMB +30 minutes HT significantly reduced, depicting 0.00062 ± 0.00096% compared to 30 minutes HT only group, showing 0.0058 ± 0.0013%. Further, results obtained from the histological analysis indicated greater cell death and reduced nucleus size in both HT alone and HT combined with USMB. CONCLUSION: The texture-based QUS parameters indicated a correlation with microstructural changes obtained from histological data. This work demonstrated the use of QUS to detect HT treatment effects in breast cancer tumors in vivo.


Assuntos
Neoplasias da Mama , Hipertermia Induzida , Neoplasias Mamárias Animais , Humanos , Animais , Camundongos , Feminino , Microbolhas , Ultrassonografia/métodos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/terapia , Neoplasias da Mama/patologia , Terapia Combinada
4.
Technol Cancer Res Treat ; 22: 15330338231200993, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37750232

RESUMO

Objectives: Prior study has demonstrated the implementation of quantitative ultrasound (QUS) for determining the therapy response in breast tumour patients. Several QUS parameters quantified from the tumour region showed a significant correlation with the patient's clinical and pathological response. In this study, we aim to identify if there exists such a link between QUS parameters and changes in tumour morphology due to combined ultrasound-stimulated microbubbles (USMB) and hyperthermia (HT) using the breast xenograft model (MDA-MB-231). Method: Tumours grown in the hind leg of severe combined immuno-deficient mice were treated with permutations of USMB and HT. Ultrasound radiofrequency data were collected using a 25 MHz array transducer, from breast tumour-bearing mice prior and post-24-hour treatment. Result: Our result demonstrated an increase in the QUS parameters the mid-band fit and spectral 0-MHz intercept with an increase in HT duration combined with USMB which was found to be reflective of tissue structural changes and cell death detected using haematoxylin and eosin and terminal deoxynucleotidyl transferase dUTP nick end labelling stain. A significant decrease in QUS spectral parameters was observed at an HT duration of 60 minutes, which is possibly due to loss of nuclei by the majority of cells as confirmed using histology analysis. Morphological alterations within the tumour might have contributed to the decrease in backscatter parameters. Conclusion: The work here uses the QUS technique to assess the efficacy of cancer therapy and demonstrates that the changes in ultrasound backscatters mirrored changes in tissue morphology.


Assuntos
Neoplasias da Mama , Hipertermia Induzida , Humanos , Animais , Camundongos , Feminino , Microbolhas , Ultrassonografia/métodos , Morte Celular , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/terapia
5.
Z Med Phys ; 33(3): 407-426, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37586962

RESUMO

Cancer is one of the leading causes of death worldwide. Several emerging technologies are helping to battle cancer. Cancer therapies have been effective at killing cancer cells, but a large portion of patients still die to this disease every year. As such, more aggressive treatments of primary cancers are employed and have been shown to be capable of saving a greater number of lives. Recent research advances the field of cancer therapy by employing the use of physical methods to alter tumor biology. It uses microbubbles to enhance radiation effect by damaging tumor vasculature followed by tumor cell death. The technique can specifically target tumor volumes by conforming ultrasound fields capable of microbubbles stimulation and localizing it to avoid vascular damage in surrounding tissues. Thus, this new application of ultrasound-stimulated microbubbles (USMB) can be utilized as a novel approach to cancer therapy by inducing vascular disruption resulting in tumor cell death. Using USMB alongside radiation has showed to augment the anti-vascular effect of radiation, resulting in enhanced tumor response. Recent work with nanobubbles has shown vascular permeation into intracellular space, extending the use of this new treatment method to potentially further improve the therapeutic effect of the ultrasound-based therapy. The significant enhancement of localized tumor cell kill means that radiation-based treatments can be made more potent with lower doses of radiation. This technique can manifest a greater impact on radiation oncology practice by increasing treatment effectiveness significantly while reducing normal tissue toxicity. This review article summarizes the past and recent advances in USMB enhancement of radiation treatments. The review mainly focuses on preclinical findings but also highlights some clinical findings that use USMB as a therapeutic modality in cancer therapy.


Assuntos
Microbolhas , Neoplasias , Humanos , Ultrassonografia , Neoplasias/diagnóstico por imagem , Neoplasias/radioterapia
7.
BMC Cancer ; 23(1): 693, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37488490

RESUMO

BACKGROUND: Radiation therapy (XRT) causes numerous biological changes in tumor microenvironment. Radiation vascular response, due to endothelial disruption, can influence treatment outcomes in a dose-dependent manner. Ultrasound-stimulated microbubbles (USMB) have also been demonstrated to create a vascular response in the tumor microenvironment and enhance tumor response when used in combination with XRT. Single doses of 8-10 Gy are known to induce activation of acid sphingomyelinase (ASMase)-induced ceramide production, causing vascular damage. Destruction of vasculature results in endothelial apoptosis followed by tumor cell death. The effect of tumor response is known to be synergistic by 10-fold higher cell kill observed when USMB is combined with radiation. METHODS: In this study, we used an USMB approach in combination with conventional low dose fractionated radiation to enhance endothelial cell responses to XRT in human PC3 prostate cancer xenograft model. Mice were divided into untreated, USMB therapy, fractionated XRT, and combined USMB therapy followed by XRT (USMB + XRT) groups. USMB therapy was delivered twice per week in the USMB-alone and combined USMB + XRT treatment groups over four weeks. Radiation treatments were delivered in fractions of 2 Gy/day (total 40 Gy in 20 fractions, BED10 = 48 Gy) in the XRT-alone and combined USMB + XRT groups. The treatment outcome was evaluated using histopathology, power Doppler, and immunohistochemistry assays. RESULTS: Tumor growth assessment showed that sizes of tumors increased in the control and the single treatment groups over a treatment period of four weeks, but significantly decreased with the combined treatments of USMB + XRT. Immunohistochemical analysis indicated a statistically significant vascular disruption in mice that received treatment involving a full 4-week schedule of combined (USMB + XRT) treatments. A statistically significant increase in vascular disruption was demonstrated through CD68 and trichrome fibrosis staining. Changes in local perfusion assessed using high-frequency power Doppler imaging demonstrated attenuated blood flow in the combined group. DISCUSSION AND CONCLUSIONS: This work demonstrates the efficacy of using USMB as a radiation sensitizer in a mouse model of human PC3 tumor xenograft. This radiation treatment enhancement modality has the advantage of targeting tumor vasculature with ultrasound stimulation that can be implemented prior to radiation treatment.


Assuntos
Microbolhas , Neoplasias da Próstata , Masculino , Humanos , Animais , Camundongos , Ultrassonografia , Terapia Combinada , Apoptose , Modelos Animais de Doenças , Microambiente Tumoral
8.
Dis Model Mech ; 16(6)2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37278613

RESUMO

Recent studies have indicated that radiotherapy affects tumour vasculature as well as tumour cells. The use of ultrasound-stimulated microbubbles (USMB) can potentially enhance the effects of radiotherapy through the activation of the acid sphingomyelinase [ASMase or sphingomyelin phosphodiesterase 1 (SMPD1)]-ceramide pathway. ASMase knockout (ASMase-/-) and wild-type (WT) mice bearing fibrosarcoma (MCA/129 tumour line) were treated with 10 Gy or 20 Gy in five fractions alongside or independently of USMB treatments. The results indicated that tumour responses to fractionated radiotherapy (fXRT) were enhanced when fXRT was coupled with USMB as part of the treatment regimen. Sphingosine-1-phosphate (S1P)-treated mice and ASMase-/- mice demonstrated radioresistance against fXRT alone, whereas only ASMase-/- mice showed radioresistance against fXRT treatment alone and when combined with USMB. Results indicated that in WT and S1P-treated cohorts, the use of USMB with fXRT enhanced the tumour response compared to use of USMB or fXRT alone. Although in WT and S1P-treated cohorts, there was enhanced vascular disruption, ASMase-/- cohorts demonstrated no significant vascular disruption, indicating the importance of ASMase in facilitating vascular changes in response to fXRT and USMB treatment.


Assuntos
Terapia Combinada , Fibrossarcoma , Microbolhas , Microambiente Tumoral , Animais , Camundongos , Camundongos Endogâmicos C57BL , Apoptose , Fibrossarcoma/radioterapia , Esfingomielina Fosfodiesterase/metabolismo , Microambiente Tumoral/efeitos da radiação , Ultrassom
9.
Technol Cancer Res Treat ; 22: 15330338231176376, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37192751

RESUMO

Radiation therapy (RT) has been the standard of care for treating a multitude of cancer types. However, ionizing radiation has adverse short and long-term side effects which have resulted in treatment complications for decades. Thus, advances in enhancing the effects of RT have been the primary focus of research in radiation oncology. To avoid the usage of high radiation doses, treatment modalities such as high-intensity focused ultrasound can be implemented to reduce the radiation doses required to destroy cancer cells. In the past few years, the use of focused ultrasound (FUS) has demonstrated immense success in a number of applications as it capitalizes on spatial specificity. It allows ultrasound energy to be delivered to a targeted focal area without harming the surrounding tissue. FUS combined with RT has specifically demonstrated experimental evidence in its application resulting in enhanced cell death and tumor cure. Ultrasound-stimulated microbubbles have recently proved to be a novel way of enhancing RT as a radioenhancing agent on its own, or as a delivery vector for radiosensitizing agents such as oxygen. In this mini-review article, we discuss the bio-effects of FUS and RT in various preclinical models and highlight the applicability of this combined therapy in clinical settings.


Assuntos
Neoplasias , Radioterapia (Especialidade) , Humanos , Microbolhas , Neoplasias/radioterapia , Ultrassonografia , Morte Celular
10.
PLoS One ; 18(5): e0277759, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37130114

RESUMO

Ultrasound-stimulated microbubbles (USMB) cause localized vascular effects and sensitize tumors to radiation therapy (XRT). We investigated acoustic parameter optimization for combining USMB and XRT. We treated breast cancer xenograft tumors with 500 kHz pulsed ultrasound at varying pressures (570 or 740 kPa), durations (1 to 10 minutes), and microbubble concentrations (0.01 to 1% (v/v)). Radiation therapy (2 Gy) was administered immediately or after a 6-hour delay. Histological staining of tumors 24 hours after treatment detected changes in cell morphology, cell death, and microvascular density. Significant cell death resulted at 570 kPa after a 1-minute exposure with 1% (v/v) microbubbles with or without XRT. However, significant microvascular disruption required higher ultrasound pressure and exposure duration greater than 5 minutes. Introducing a 6-hour delay between treatments (USMB and XRT) showed a similar tumor effect with no further improvement in response as compared to when XRT was delivered immediately after USMB.


Assuntos
Neoplasias da Mama , Neoplasias Mamárias Animais , Terapia por Ultrassom , Animais , Humanos , Feminino , Neoplasias da Mama/radioterapia , Neoplasias da Mama/patologia , Terapia por Ultrassom/métodos , Microbolhas , Morte Celular/efeitos da radiação , Ultrassonografia
11.
Sci Rep ; 13(1): 4487, 2023 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-36934140

RESUMO

High intensity focused ultrasound (HIFU) systems have been approved for therapeutic ultrasound delivery to cause tissue ablation or induced hyperthermia. Microbubble agents have also been used in combination with sonication exposures. These require temperature feedback and monitoring to prevent unstable cavitation and prevent excess tissue heating. Previous work has utilized lower power and pressure to oscillate microbubbles and transfer energy to endothelial cells in the absence of thermally induced damage that can radiosensitize tumors. This work investigated whether reduced acoustic power and pressure on a commercial available MR-integrated HIFU system could result in enhanced radiation-induced tumor response after exposure to ultrasound-stimulated microbubbles (USMB) therapy. A commercially available MR-integrated HIFU system was used with a hyperthermia system calibration provided by the manufacturer. The ultrasound transducer was calibrated to reach a peak negative pressure of - 750 kPa. Thirty male New Zealand white rabbits bearing human derived PC3 tumors were grouped to receive no treatment, 14 min of USMB, 8 Gy of radiation in a separate irradiation cabinet, or combined treatments. In vivo temperature changes were collected using MR thermometry at the tumor center and far-field muscle region. Tissues specimens were collected 24 h post radiation therapy. Tumor cell death was measured and compared to untreated controls through hematoxylin and eosin staining and immunohistochemical analysis. The desired peak negative pressure of - 750 kPa used for previous USMB occurred at approximately an input power of 5 W. Temperature changes were limited to under 4 °C in ten of twelve rabbits monitored. The median temperature in the far-field muscle region of the leg was 2.50 °C for groups receiving USMB alone or in combination with radiation. Finally, statistically significant tumor cell death was demonstrated using immunohistochemical analysis in the combined therapy group compared to untreated controls. A commercial MR-guided therapy HIFU system was able to effectively treat PC3 tumors in a rabbit model using USMB therapy in combination with radiation exposures. Future work could find the use of reduced power and pressure levels in a commercial MR-guided therapy system to mechanically stimulate microbubbles and damage endothelial cells without requiring high thermal doses to elicit an antitumor response.


Assuntos
Ablação por Ultrassom Focalizado de Alta Intensidade , Neoplasias Induzidas por Radiação , Masculino , Humanos , Coelhos , Animais , Microbolhas , Células Endoteliais , Temperatura , Imageamento por Ressonância Magnética
12.
Cancers (Basel) ; 14(24)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36551702

RESUMO

Quantitative ultrasound (QUS) is a non-invasive novel technique that allows treatment response monitoring. Studies have shown that QUS backscatter variables strongly correlate with changes observed microscopically. Increases in cell death result in significant alterations in ultrasound backscatter parameters. In particular, the parameters related to scatterer size and scatterer concentration tend to increase in relation to cell death. The use of QUS in monitoring tumor response has been discussed in several preclinical and clinical studies. Most of the preclinical studies have utilized QUS for evaluating cell death response by differentiating between viable cells and dead cells. In addition, clinical studies have incorporated QUS mostly for tissue characterization, including classifying benign versus malignant breast lesions, as well as responder versus non-responder patients. In this review, we highlight some of the important findings of previous preclinical and clinical studies and expand the applicability and therapeutic benefits of QUS in clinical settings. We summarized some recent clinical research advances in ultrasound-based radiomics analysis for monitoring and predicting treatment response and characterizing benign and malignant breast lesions. We also discuss current challenges, limitations, and future prospects of QUS-radiomics.

13.
MMWR Morb Mortal Wkly Rep ; 71(50): 1569-1575, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36520657

RESUMO

In 2019, India, along with other countries in the World Health Organization (WHO) South-East Asia Region,* adopted the goal of measles and rubella elimination by 2023,† a revision of the previous goal of measles elimination and control of rubella and congenital rubella syndrome (CRS) by 2020§ (1-3). During 2017-2021, India adopted a national strategic plan for measles and rubella elimination (4), introduced rubella-containing vaccine (RCV) into the routine immunization program, launched a nationwide measles-rubella supplementary immunization activity (SIA) catch-up campaign, transitioned from outbreak-based surveillance to case-based acute fever and rash surveillance, and more than doubled the number of laboratories in the measles-rubella network, from 13 to 27. Strategies included 1) achieving and maintaining high population immunity with at least 95% vaccination coverage by providing 2 doses of measles- and rubella-containing vaccines; 2) ensuring a sensitive and timely case-based measles, rubella and CRS surveillance system; 3) maintaining an accredited measles and rubella laboratory network; 4) ensuring adequate outbreak preparedness and rapid response to measles and rubella outbreaks; and 5) strengthening support and linkages to achieve these strategies, including planning and progress monitoring, advocacy, social mobilization and communication, identification and utilization of synergistic linkages of integrated program efforts, research, and development. This report describes India's progress toward the elimination of measles and rubella during 2005-2021, with a focus on the years 2017-2021.¶ During 2005-2021, coverage with the first dose of a measles-containing vaccine (MCV) administered through routine immunization increased 31%, from 68% to 89%. During 2011-2021, coverage with a second MCV dose (MCV2) increased by 204%, from 27% to 82%. During 2017-2021, coverage with a first dose of RCV (RCV1) increased almost 14-fold, from 6% to 89%. More than 324 million children received a measles- and rubella-containing vaccine (MRCV) during measles-rubella SIAs completed in 34 (94%) of 36 states and union territories (states) during 2017-2019. During 2017-2021, annual measles incidence decreased 62%, from 10.4 to 4.0 cases per 1 million population, and rubella incidence decreased 48%, from 2.3 to 1.2 cases per 1 million population. India has made substantial progress toward measles and rubella elimination; however, urgent and intensified efforts are required to achieve measles and rubella elimination by 2023.


Assuntos
Sarampo , Síndrome da Rubéola Congênita , Rubéola (Sarampo Alemão) , Criança , Humanos , Lactente , Erradicação de Doenças , Esquemas de Imunização , Vigilância da População , Sarampo/epidemiologia , Sarampo/prevenção & controle , Vacina contra Sarampo , Rubéola (Sarampo Alemão)/epidemiologia , Rubéola (Sarampo Alemão)/prevenção & controle , Programas de Imunização , Vacina contra Rubéola , Síndrome da Rubéola Congênita/epidemiologia , Síndrome da Rubéola Congênita/prevenção & controle
14.
Technol Cancer Res Treat ; 21: 15330338221132925, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36412102

RESUMO

Objective: Several studies have focused on the use of ultrasound-stimulated microbubbles (USMB) to induce vascular damage in order to enhance tumor response to radiation. Methods: In this study, power Doppler imaging was used along with immunohistochemistry to investigate the effects of combining radiation therapy (XRT) and USMB using an ultrasound-guided focused ultrasound (FUS) therapy system in a breast cancer xenograft model. Specifically, MDA-MB-231 breast cancer xenograft tumors were induced in severe combined immuno-deficient female mice. The mice were treated with FUS alone, ultrasound and microbubbles (FUS + MB) alone, 8 Gy XRT alone, or a combined treatment consisting of ultrasound, microbubbles, and XRT (FUS + MB + XRT). Power Doppler imaging was conducted before and 24 h after treatment, at which time mice were sacrificed and tumors assessed histologically. The immunohistochemical analysis included terminal deoxynucleotidyl transferase dUTP nick end labeling, hematoxylin and eosin, cluster of differentiation-31 (CD31), Ki-67, carbonic anhydrase (CA-9), and ceramide labeling. Results: Tumors receiving treatment of FUS + MB combined with XRT demonstrated significant increase in cell death (p = 0.0006) compared to control group. Furthermore, CD31 and Power Doppler analysis revealed reduced tumor vascularization with combined treatment indicating (P < .0001) and (P = .0001), respectively compared to the control group. Additionally, lesser number of proliferating cells with enhanced tumor hypoxia, and ceramide content were also reported in group receiving a treatment of FUS + MB + XRT. Conclusion: The study results demonstrate that the combination of USMB with XRT enhances treatment outcomes.


Assuntos
Neoplasias da Mama , Terapia por Ultrassom , Humanos , Feminino , Animais , Camundongos , Microbolhas , Xenoenxertos , Terapia por Ultrassom/métodos , Ceramidas/metabolismo , Neoplasias da Mama/radioterapia
15.
Carbohydr Polym ; 298: 120052, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36241259

RESUMO

Nanocellulose (NC) is the biological polymeric nanomaterial booming in the international market. The burgeoning demand for cellulose materials and advancements in nanotechnology have intensified the researches on the development of cellulose-based nanomaterials. Substantial research on nanocellulose-based composites in energy, electronics, biomedical, health, and the environment has been carried out in the last few decades. NC offers a plethora of outstanding properties such as biodegradability, renewability, and excellent fibrous structure. The recent advancement in the synthetic methodologies for various types of nanocellulose materials and their applications in a myriad of fields such as biosensing, chemical sensing, gas sensing, and strain sensing have been explored. The surface modification ability and robust nature of NC offer various possibilities for hybrid materials in the sensing field. Many sensors developed on plastic, paper, and glass platforms will be replaced with NC to modify the conventional sensing probes in the near future.


Assuntos
Celulose , Nanoestruturas , Celulose/química , Nanoestruturas/química , Nanotecnologia , Plásticos , Polímeros
16.
Indian J Med Res ; 155(1): 129-135, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35859439

RESUMO

Background & objectives: Polio, measles, rubella, influenza and rotavirus surveillance programmes are of great public health importance globally. Virus isolation using cell culture is an integral part of such programmes. Possibility of unintended isolation of SARS-CoV-2 from clinical specimens processed in biosafety level-2 (BSL-2) laboratories during the above-mentioned surveillance programmes, cannot be ruled out. The present study was conducted to assess the susceptibility of different cell lines to SARS-CoV-2 used in these programmes. Methods: Replication of SARS-CoV-2 was studied in RD and L20B, Vero/hSLAM, MA-104 and Madin-Darby Canine Kidney (MDCK) cell lines, used for the isolation of polio, measles, rubella, rotavirus and influenza viruses, respectively. SARS-CoV-2 at 0.01 multiplicity of infection was inoculated and the viral growth was assessed by observation of cytopathic effects followed by real-time reverse transcription-polymerase chain reaction (qRT-PCR). Vero CCL-81 cell line was used as a positive control. Results: SARS-CoV-2 replicated in Vero/hSLAM, and MA-104 cells, whereas it did not replicate in L20B, RD and MDCK cells. Vero/hSLAM, and Vero CCL-81 showed rounding, degeneration and detachment of cells; MA-104 cells also showed syncytia formation. In qRT-PCR, Vero/hSLAM and MA-104 showed 106 and Vero CCL-81 showed 107 viral RNA copies per µl. The 50 per cent tissue culture infectious dose titres of Vero/hSLAM, MA-104 and Vero CCL-81 were 105.54, 105.29 and 106.45/ml, respectively. Interpretation & conclusions: Replication of SARS-CoV-2 in Vero/hSLAM and MA-104 underscores the possibility of its unintended isolation during surveillance procedures aiming to isolate measles, rubella and rotavirus. This could result in accidental exposure to high titres of SARS-CoV-2, which can result in laboratory acquired infections and community risk, highlighting the need for revisiting biosafety measures in public health laboratories.


Assuntos
COVID-19 , Sarampo , Poliomielite , Rubéola (Sarampo Alemão) , Animais , Linhagem Celular , Chlorocebus aethiops , Contenção de Riscos Biológicos , Cães , Vigilância em Saúde Pública , SARS-CoV-2 , Células Vero
17.
Int J Mol Sci ; 23(12)2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35743121

RESUMO

Sphingolipids are well-recognized critical components in several biological processes. Ceramides constitute a class of sphingolipid metabolites that are involved in important signal transduction pathways that play key roles in determining the fate of cells to survive or die. Ceramide accumulated in cells causes apoptosis; however, ceramide metabolized to sphingosine promotes cell survival and angiogenesis. Studies suggest that vascular-targeted therapies increase endothelial cell ceramide resulting in apoptosis that leads to tumour cure. Specifically, ultrasound-stimulated microbubbles (USMB) used as vascular disrupting agents can perturb endothelial cells, eliciting acid sphingomyelinase (ASMase) activation accompanied by ceramide release. This phenomenon results in endothelial cell death and vascular collapse and is synergistic with other antitumour treatments such as radiation. In contrast, blocking the generation of ceramide using multiple approaches, including the conversion of ceramide to sphingosine-1-phosphate (S1P), abrogates this process. The ceramide-based cell survival "rheostat" between these opposing signalling metabolites is essential in the mechanotransductive vascular targeting following USMB treatment. In this review, we aim to summarize the past and latest findings on ceramide-based vascular-targeted strategies, including novel mechanotransductive methodologies.


Assuntos
Células Endoteliais , Neoplasias Induzidas por Radiação , Ceramidas/metabolismo , Células Endoteliais/metabolismo , Humanos , Lisofosfolipídeos/metabolismo , Transdução de Sinais , Esfingolipídeos/metabolismo , Esfingosina/metabolismo
18.
Int J Mol Sci ; 23(8)2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35457210

RESUMO

At present, cancer is one of the leading causes of death worldwide. Treatment failure remains one of the prime hurdles in cancer treatment due to the metastatic nature of cancer. Techniques have been developed to hinder the growth of tumours or at least to stop the metastasis process. In recent years, ultrasound therapy combined with microbubbles has gained immense success in cancer treatment. Ultrasound-stimulated microbubbles (USMB) combined with other cancer treatments including radiation therapy, chemotherapy or immunotherapy has demonstrated potential improved outcomes in various in vitro and in vivo studies. Studies have shown that low dose radiation administered with USMB can have similar effects as high dose radiation therapy. In addition, the use of USMB in conjunction with radiotherapy or chemotherapy can minimize the toxicity of high dose radiation or chemotherapeutic drugs, respectively. In this review, we discuss the biophysical properties of USMB treatment and its applicability in cancer therapy. In particular, we highlight important preclinical and early clinical findings that demonstrate the antitumour effect combining USMB and other cancer treatment modalities (radiotherapy and chemotherapy). Our review mainly focuses on the tumour vascular effects mediated by USMB and these cancer therapies. We also discuss several current limitations, in addition to ongoing and future efforts for applying USMB in cancer treatment.


Assuntos
Neoplasias , Terapia por Ultrassom , Linhagem Celular Tumoral , Terapia Combinada , Microbolhas , Neoplasias/terapia , Terapia por Ultrassom/métodos , Ultrassonografia
19.
Bull World Health Organ ; 100(4): 247-255, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35386556

RESUMO

Objective: To expand the measles and rubella laboratory network of India by integrating new laboratories. Methods: In collaboration with the World Health Organization (WHO), the Indian government developed a 10-step scheme to systematically expand the number of laboratories performing serological and molecular testing for measles and rubella. The Indian Council of Medical Research and WHO identified suitable laboratories based on their geographical location, willingness, preparedness, past performance and adherence to national quality control and quality assurance mechanisms. The 10-step scheme was initiated with training on measles and rubella diagnostic assays followed by testing of both measles and rubella serology and molecular unknown panels, cross-verification with reference laboratories and ended with WHO on-site accreditation. Findings: After extensive training, technical support, funding and monitoring, all six selected laboratories attained passing scores of 90.0% or more in serological and molecular proficiency testing of measles and rubella. Since 2018, the laboratories are a part of the measles and rubella network of India. Within 12 months of initiation of independent reporting, the six laboratories have tested 2287 serum samples and 701 throat or nasopharyngeal swabs or urine samples. Conclusion: The process led to strengthening and expansion of the network. This proficient laboratory network has helped India in scaling up serological and molecular testing of measles and rubella while ensuring high quality testing. The collaborative model developed by the Indian government with WHO can be implemented by other countries for expanding laboratory networks for surveillance of measles and rubella as well as other infectious diseases.


Assuntos
Sarampo , Rubéola (Sarampo Alemão) , Saúde Global , Humanos , Índia , Laboratórios , Sarampo/diagnóstico , Sarampo/epidemiologia , Sarampo/prevenção & controle , Rubéola (Sarampo Alemão)/diagnóstico , Rubéola (Sarampo Alemão)/epidemiologia , Rubéola (Sarampo Alemão)/prevenção & controle
20.
J Ultrasound Med ; 41(11): 2659-2671, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35142383

RESUMO

OBJECTIVE: The objective of the present study was to investigate the treatment effects of ultrasound-stimulated microbubbles (USMB) and hyperthermia (HT) on breast tumor vasculature. METHODS: Tumor-bearing mice with breast cancer xenografts (MDA-MB-231), were exposed to different treatment conditions consisting of control (no treatment), USMB alone, HT alone, USMB with HT exposures of 10 and 50 minutes. Quantitative 3D Doppler ultrasound and photoacoustic imaging were used to detect tumor blood flow and oxygen saturation, respectively. In addition, histopathological analysis including TUNEL staining for cell death, and CD31 staining for the vessel count, was performed to complement the results of power Doppler and photoacoustic imaging. RESULTS: Results demonstrated a decrease in tumor blood flow as well as oxygenation level following 50 minutes HT treatment either alone or combined with USMB. In contrast, 10 minutes HT alone or combined with USMB had minimal effects on blood flow and tumor oxygenation level. Treatment with HT for 50 minutes caused drops in tumor oxygenation, which were not evident with USMB treatment alone. Additionally, results revealed an increase in cell death after 10 minutes HT with or without USMB and a decrease in vessel count compared to control. Unlike previous studies which demonstrated synergistic treatment effects combining USMB with other modalities such as radiation or chemotherapy, USMB and HT effects were not synergistic in the present study. CONCLUSION: The results here demonstrated HT and USMB both alone or together resulted in a significant reduction in tumor blood flow, tumor oxygenation, and vessel count with observed increases in cell death response.


Assuntos
Neoplasias da Mama , Hipertermia Induzida , Humanos , Camundongos , Animais , Feminino , Microbolhas , Xenoenxertos , Neoplasias da Mama/terapia , Neoplasias da Mama/patologia , Ultrassonografia , Linhagem Celular Tumoral
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