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1.
J Cell Mol Med ; 28(10): e18397, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38766687

RESUMO

Malignant insulinoma is an extremely rare type of functioning pancreatic neuroendocrine tumour with a high degree of malignancy and a high incidence of metastasis. However, it is still unclear how malignant insulinomas develop and metastasize. Serum amyloid P component (SAP), a member of the pentraxin protein family, is an acute-phase protein secreted by liver cells. The role of SAP in insulinoma and the related mechanism are still unknown. To determine the effect of SAP on insulinoma, we crossed Rip1-Tag2 mice, which spontaneously develop insulinoma, and SAP knockout (KO) mice to generate Rip1-Tag2;SAP-/- mice. We found that SAP deletion significantly promoted the growth, invasion and metastasis of malignant insulinoma through C-X-C motif chemokine ligand 12 (CXCL12) secreted by cancer-associated fibroblasts (CAFs). Further study showed that SAP deletion promoted CXCL12 secretion by CAFs through the CXCR4/p38/ERK signalling pathway. These findings reveal a novel role and mechanism of SAP in malignant insulinoma and provide direct evidence that SAP may be a therapeutic agent for this disease.


Assuntos
Quimiocina CXCL12 , Insulinoma , Sistema de Sinalização das MAP Quinases , Camundongos Knockout , Receptores CXCR4 , Animais , Insulinoma/metabolismo , Insulinoma/patologia , Insulinoma/genética , Quimiocina CXCL12/metabolismo , Quimiocina CXCL12/genética , Receptores CXCR4/metabolismo , Receptores CXCR4/genética , Camundongos , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Deleção de Genes , Progressão da Doença , Humanos , Linhagem Celular Tumoral , Proliferação de Células
2.
Ultrasonics ; 140: 107315, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38603903

RESUMO

Lung diseases are commonly diagnosed based on clinical pathological indications criteria and radiological imaging tools (e.g., X-rays and CT). During a pandemic like COVID-19, the use of ultrasound imaging devices has broadened for emergency examinations by taking their unique advantages such as portability, real-time detection, easy operation and no radiation. This provides a rapid, safe, and cost-effective imaging modality for screening lung diseases. However, the current pulmonary ultrasound diagnosis mainly relies on the subjective assessments of sonographers, which has high requirements for the operator's professional ability and clinical experience. In this study, we proposed an objective and quantifiable algorithm for the diagnosis of lung diseases that utilizes two-dimensional (2D) spectral features of ultrasound radiofrequency (RF) signals. The ultrasound data samples consisted of a set of RF signal frames, which were collected by professional sonographers. In each case, a region of interest of uniform size was delineated along the pleural line. The standard deviation curve of the 2D spatial spectrum was calculated and smoothed. A linear fit was applied to the high-frequency segment of the processed data curve, and the slope of the fitted line was defined as the frequency spectrum standard deviation slope (FSSDS). Based on the current data, the method exhibited a superior diagnostic sensitivity of 98% and an accuracy of 91% for the identification of lung diseases. The area under the curve obtained by the current method exceeded the results obtained that interpreted by professional sonographers, which indicated that the current method could provide strong support for the clinical ultrasound diagnosis of lung diseases.


Assuntos
Algoritmos , COVID-19 , Pneumopatias , Ultrassonografia , Humanos , Ultrassonografia/métodos , Pneumopatias/diagnóstico por imagem , COVID-19/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Masculino , Feminino , Pessoa de Meia-Idade , Interpretação de Imagem Assistida por Computador/métodos , SARS-CoV-2
3.
J Affect Disord ; 350: 420-427, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38244785

RESUMO

BACKGROUND: Rapid urbanization is a major trend in global population migration. There is growing debate about whether this urban-rural disparity exacerbate depression at the individual level. This study aims to investigate how urban living has a beneficial impact on individual mental health. METHODS: Based on the data of 15,764 participants in the 2018 China Health and Retirement Longitudinal Study (CHARLS), we perform analysis of variance to identify the gap in depression levels between urban and rural areas. Extensive comparisons and detailed statistical analyses are carried out to demonstrate the differences in social participation between urban and rural residents. Finally, we conduct a series of mediation and moderation analyses to reveal the underlying mechanisms of depressive disorder benefits of cities. RESULTS: The results indicate that those who lived in urban areas were less likely to suffer from depression (ß = -1.461, 95 % CI = [-1.691, -1.235], p < 0.001). Social engagement is found to mediate the relationship between residence type (ß = 0.164, 95 % CI = [0.136, 0.193], p < 0.001) and individual depression (ß = -0.462, 95 % CI = [-0.587, -0.337], p < 0.001). City size plays a moderating role in the association between urban living and social engagement. LIMITATIONS: The mechanism is conducted through cross-sectional data. Self-reported depression status is accessed in this study, which could lead to measurement error. CONCLUSION: This study demonstrates the beneficial effects of urban living on individual depression, and reveals the mechanism by which urbanization at different scales affects the prevalence of depression.


Assuntos
Transtorno Depressivo , População Rural , Humanos , Cidades , População Urbana , Estudos Longitudinais , Estudos Transversais , China/epidemiologia , Transtorno Depressivo/epidemiologia , Depressão/epidemiologia , Depressão/psicologia
4.
Ultrasonics ; 138: 107227, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38118237

RESUMO

Ultrasonic cavitation, characterized by the oscillation or abrupt collapse of cavitation nuclei in response to ultrasound stimulation, plays a significant role in various applications within both industrial and biomedical sectors. In particular, inertial cavitation (IC) has garnered considerable attention due to the resulting mechanical, chemical, and thermal effects. Passive cavitation detection (PCD) has emerged as a valuable technique for monitoring this procedure. While the fast Fourier transform (FFT) is a widely used algorithm to analyze IC-induced broadband noise detected by PCD system, it may not adequately capture the time-varying instability of cavitation due to potential nuclei collapse during ultrasound irradiation. In contrast, the continuous wavelet transform offers a more flexible approach, enabling more sensitive analysis of signals with varying frequencies over time. In this study, nanodiamond (ND) and its derivative, nitro-doped nanodiamond (N-AND), known to possess cavitation potential from previous research, were chosen as the source of cavitation nuclei. The cavitation signals detected by PCD were subjected to both FFT and wavelet analyses, with their results comprehensively compared. This research showcased the feasibility of employing wavelet analysis for effective inertial cavitation evaluation. It provided the advantage of monitoring the temporal evolution of cavitation events in real-time, enhancing sensitivity to weak and unstable cavitation signals, especially those in higher order components (3rd and 4th order). Additionally, it yielded a higher level of precision in determining IC thresholds and doses. Furthermore, the inclusion of time information through wavelet analysis offered insights into the limitations of low-cycle ultrasound in inducing IC. This study introduces a novel perspective for more sensitive and precise cavitation assessment, leveraging time and frequency data from wavelet analysis, and holds promise for effective utilization of cavitation effects while minimizing losses and damages resulting from unintended cavitation events.

5.
Am J Case Rep ; 24: e941627, 2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38069462

RESUMO

BACKGROUND Gitelman syndrome (GS) is a rare inherited autosomal recessive salt-losing renal tubulopathy. Early-onset GS is difficult to differentiate from Bartter syndrome (BS). It has been reported in some cases that cyclooxygenase (COX) inhibitors, which pharmacologically reduce prostaglandin E2(PGE2) synthesis, are helpful for GS patients, especially in children, but the long-term therapeutic effect has not yet been revealed. CASE REPORT A 4-year-old boy was first brought to our hospital for the chief concern of short stature and growth retardation. Biochemical tests demonstrated severe hypokalemia, hyponatremia, and hypochloremic metabolic alkalosis. The patient's serum magnesium was normal. He was diagnosed with BS and treated with potassium supplementation and indomethacin and achieved stable serum potassium levels and slow catch-up growth. At 11.8 years of age, the patient showed hypomagnesemia and a genetic test confirmed that he had GS with compound heterozygous mutations in the SLC12A3 gene. At the age of 14.8 years, when indomethacin had been taken for nearly 10 years, the boy reported having chronic stomachache, while his renal function remained normal. After proton pump inhibitor and acid inhibitor therapy, the patient's symptoms were ameliorated, and he continued to take a low dose of indomethacin (37.5 mg/d divided tid) with good tolerance. CONCLUSIONS Early-onset GS in childhood can be initially misdiagnosed as BS, and gene detection can confirm the final diagnosis. COX inhibitors, such as indomethacin, might be tolerated by pediatric patients, and long-term therapy can improve the hypokalemia and growth retardation without significant adverse effects.


Assuntos
Síndrome de Bartter , Síndrome de Gitelman , Hipopotassemia , Adolescente , Criança , Pré-Escolar , Humanos , Masculino , Síndrome de Bartter/genética , China , Síndrome de Gitelman/diagnóstico , Síndrome de Gitelman/tratamento farmacológico , Síndrome de Gitelman/genética , Transtornos do Crescimento/complicações , Hipopotassemia/tratamento farmacológico , Hipopotassemia/etiologia , Indometacina/uso terapêutico , Potássio , Membro 3 da Família 12 de Carreador de Soluto/genética , Membro 3 da Família 12 de Carreador de Soluto/metabolismo
6.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(11): 1113-1117, 2023 Nov 15.
Artigo em Chinês | MEDLINE | ID: mdl-37990454

RESUMO

OBJECTIVES: To investigate the difference in the therapeutic effect of mycophenolate mofetil (MMF) or cyclophosphamide (CTX) in children with Henoch-Schönlein purpura nephritis (HSPN) of different age groups. METHODS: A retrospective analysis was conducted on the clinical data of 135 children with HSPN who were treated with MMF or CTX in the Department of Nephrology, Children's Hospital Affiliated to Capital Institute of Pediatrics, from October 2018 to October 2020. According to the immunosuppressant used, they were divided into two groups: MMF group and CTX group, and according to the age, each group was further divided into two subgroups: ≤12 years and >12 years, producing four groups, i.e, the ≤12 years MMF subgroup (n=30), the >12 years MMF subgroup (n=15), the ≤12 years CTX subgroup (n=71), and the >12 years CTX subgroup (n=19). All children were followed up for at least 12 months, and the above groups were compared in terms of clinical outcomes and the incidence rate of adverse reactions. RESULTS: There was no significant difference in the complete response rate between the MMF group and the CTX group after 3, 6, and 12 months of treatment (P>0.05). There were no significant difference in the complete response rate and the incidence rate of adverse reactions between the >12 years MMF subgroup and the ≤12 years MMF subgroup at 3, 6, and 12 months of treatment (P>0.05). The >12 years CTX subgroup had a significantly lower complete response rate than the ≤12 years CTX subgroup at 6 and 12 months of treatment (P<0.05). The >12 years CTX subgroup had a significantly higher incidence rate of adverse reactions than the >12 years MMF subgroup (P<0.05). CONCLUSIONS: The efficacy and adverse reactions of MMF are not associated with age, but the efficacy of CTX is affected by age, with a higher incidence rate of adverse reactions. CTX should be selected with caution for children with HSPN aged >12 years.


Assuntos
Vasculite por IgA , Nefrite , Vasculite , Criança , Humanos , Ácido Micofenólico/efeitos adversos , Vasculite por IgA/tratamento farmacológico , Estudos Retrospectivos , Ciclofosfamida/efeitos adversos , Imunossupressores/efeitos adversos , Vasculite/induzido quimicamente , Vasculite/complicações , Vasculite/tratamento farmacológico , Nefrite/etiologia , Nefrite/complicações
7.
Heliyon ; 9(10): e20684, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37842633

RESUMO

Depression has become a widespread health concern today. Understanding the influencing factors can promote human mental health as well as provide a basis for exploring preventive measures. Combining LassoNet with recurrent neural network (RNN), this study constructed a screening model ,LassoNet-RNN, for identifying influencing factors of individual depression. Based on multi-wave surveys of China Health and Retirement Longitudinal Study (CHARLS) dataset (11,661 observations), we analyzed the multivariate time series data and recognized 27 characteristic variables selected from four perspectives: demographics, health-related risk factors, household economic status, and living environment. Additionally, the importance rankings of the characteristic variables were obtained. These results offered insightful recommendations for theoretical developments and practical decision making in public health.

8.
Arch Public Health ; 81(1): 166, 2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37679764

RESUMO

BACKGROUND: The Coronavirus Disease 2019 (COVID-19) pandemic was a huge shock to society, and the ensuing information problems had a huge impact on society at the same time. The urgent need to understand the Infodemic, i.e., the importance of the spread of false information related to the epidemic, has been highlighted. However, while there is a growing interest in this phenomenon, studies on the topic discovery, data collection, and data preparation phases of the information analysis process have been lacking. OBJECTIVE: Since the epidemic is unprecedented and has not ended to this day, we aimed to examine the existing Infodemic-related literature from January 2019 to December 2022. METHODS: We have systematically searched ScienceDirect and IEEE Xplore databases with some search limitations. From the searched literature we selected titles, abstracts and keywords, and limitations sections. We conducted an extensive structured literature search and analysis by filtering the literature and sorting out the available information. RESULTS: A total of 47 papers ended up meeting the requirements of this review. Researchers in all of these literatures encountered different challenges, most of which were focused on the data collection step, with few challenges encountered in the data preparation phase and almost none in the topic discovery section. The challenges were mainly divided into the points of how to collect data quickly, how to get the required data samples, how to filter the data, what to do if the data set is too small, how to pick the right classifier and how to deal with topic drift and diversity. In addition, researchers have proposed partial solutions to the challenges, and we have also proposed possible solutions. CONCLUSIONS: This review found that Infodemic is a rapidly growing research area that attracts the interest of researchers from different disciplines. The number of studies in this field has increased significantly in recent years, with researchers from different countries, including the United States, India, and China. Infodemic topic discovery, data collection, and data preparation are not easy, and each step faces different challenges. While there is some research in this emerging field, there are still many challenges that need to be addressed. These findings highlight the need for more articles to address these issues and fill these gaps.

9.
Heliyon ; 9(7): e17766, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37539221

RESUMO

Background: Sepsis is a common complication of many diseases and is associated with high morbidity and mortality rates. Astragalus can improve humoral and innate immunity, inhibit inflammatory responses, and protect immune cells and organs from damage. However, to the best of our knowledge there are no reports on whether astragalus can regulate intestinal innate immune function during sepsis. Methods: In this study, a rat cecal ligation and puncture model of sepsis was used to investigate the effects of astragalus treatment, following which the apoptosis rate of lymphocytes from Peyer's patches (PP) was determined. Type 3 innate lymphoid cells (ILC3) were cultured in vitro to further evaluate the effects and mechanisms of astragalus. Results: The apoptosis level of lymphocytes from PP in rats with sepsis was significantly increased, and the number of ILC3 was significantly reduced, compared with the sham operation group, which aggravated intestinal injury and ultimately led to the death of rats. Astragalus treatment significantly inhibited the apoptosis of lymphocytes from PP, increased the number of ILC3, and improved the intestinal inflammatory environment compared to the sepsis group. RT-PCR revealed that astragalus and the retinoic acid-related orphan receptor γt (RORγt) agonist LYC-55716 both promote the expression of interleukin (IL)-17A, IL-17F, IL-22, interferon-γ, and granulocyte-macrophage colony-stimulating factor mRNA. Mechanistically, astragalus promotes the proliferation of ILC3 through RORγt, thereby reducing intestinal inflammatory damage. Conclusion: Astragalus, via RORγt, promotes the generation of ILC3, improves the inflammatory environment in rats with sepsis.

10.
Ultrason Sonochem ; 99: 106563, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37647744

RESUMO

In biomedical research, ultrasonic cavitation, especially inertial cavitation (IC) has attracted extensive attentions due to its ability to induce mechanical, chemical and thermal effects. Like ultrasound contrast agent (UCA) microbubbles or droplets, acoustic cavitation can be effectively triggered beyond a certain pressure threshold through the interaction between ultrasound and nucleation particles, leading to an enhanced thrombolytic effect. As a newly developed nanocarbon material, nitrogen-doped annealed nanodiamond (N-AND) has shown promising catalytic performance. To further explore its effects on ultrasonic cavitation, N-AND was synthesized at the temperature of 1000 °C. After systematic material characterization, the potential of N-AND to induce enhanced IC activity was assessed for the first time by using passive cavitation detection (PCD). Based on experiments performed at varied material suspension concentration and cycle number, N-AND demonstrated a strong capability to generate significant cavitation characteristics, indicating the formation of stable bubbles from the surface of the materials. Furthermore, N-AND was applied in the in vitro thrombolysis experiments to verify its contribution to ultrasound thrombolysis. The influence of surface hydrophobicity on the cavitation potentials of ND and N-AND was innovatively discussed in combination with the theory of mote-induced nucleation. It is found that the cavitation stability of N-AND was better than that of the commercial UCA microbubbles. This study would provide better understanding of the potential of novel carbonous nanomaterials as cavitation nuclei and is expected to provide guidance for their future biomedical and industrial applications.

11.
Artigo em Inglês | MEDLINE | ID: mdl-37490370

RESUMO

In ultrasonic imaging, high impedance obstacles in tissues may lead to artifacts behind them, making the examination of the target area difficult. Acoustical Airy beams possess the characteristics of self-bending and self-healing within a specific range. They are limited-diffracting when generated from finite aperture sources and are expected to have great potential in medical imaging and therapy. In this article, pulsed Airy (pAiry) beams are employed for ultrasonic imaging at megahertz frequency, and the protocol is demonstrated via both simulations and experiments. First, the generation of pAiry beams using a linear array is simulated, and the pulsed beams inherit some characteristics of continuous wave Airy beams, such as propagating along curved paths and self-healing. In experiments where obstacles are present at the beam paths, the image quality in pAiry-based imaging is superior to that in classical iso-depth imaging. The results demonstrate the feasibility and benefits of ultrasonic imaging based on pAiry beams and provide an important basis for developing imaging techniques employing nondiffracting acoustic beams.

12.
Artigo em Inglês | MEDLINE | ID: mdl-37379173

RESUMO

While thermal therapy is increasingly applied in clinics, real-time temperature monitoring in the target tissue can facilitate improvements in the planning, controlling, and evaluating of therapeutic procedures. Thermal strain imaging (TSI), based on tracking the echo shifts in ultrasound images, has great potential for temperature estimation as is demonstrated in vitro. However, due to physiological motion-induced artifacts and estimation errors, employing TSI for in vivo thermometry is still challenging. Building on our earlier development of respiration-separated TSI (RS-TSI), a multithread TSI (MT-TSI) approach is proposed as the first part of a bigger plan. A flag image frame is first identified by analyzing the correlation between ultrasound images. Then, the quasi-periodic phase profile of respiration is determined and split into multiple parallelly distributed periodical subranges. Multiple threads of independent TSI calculations are thus established, with image matching, motion compensation, and thermal strain estimation performed in each thread. Finally, after applying temporal extrapolation, spatial alignment, and interthread noise suppression, the TSI results obtained in different threads are averaged to obtain the merged output. In microwave (MW) heating experiments targeting porcine perirenal fat, the thermometry accuracy of MT-TSI is comparable to that of RS-TSI, while the former exhibits lower noise and higher temporal density.


Assuntos
Termometria , Animais , Suínos , Ultrassonografia/métodos , Termometria/métodos , Temperatura , Imageamento por Ressonância Magnética/métodos
13.
J Affect Disord ; 334: 246-257, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37146909

RESUMO

OBJECTIVES: Weak ties are becoming mainstream in daily relationships and play an essential role in the improvement of individuals' mental health. Despite growing concerns on depression, inclusion of weak ties is limited. To address the gap, this study empirically shed light on the role of weak ties on individual depression in the context of economic development. METHOD: A cross-sectional study was conducted based on 2018 China Health and Retirement Longitudinal Study (CHARLS) with a sample of 16,545 individuals. A moderated mediation model is constructed to evaluate the impact of economic development (GDP) on the degrees of depression, the mediating effect of weak ties, and the moderating effect of residents' residence types (living in urban or rural areas). RESULTS: Economic development exerts a significant direct impact on depression (ß=-1.027, p<0.001). Weak ties are significantly negatively correlated with depression (ß=-0.574, p<0.001), and act as a mediator between economic development and local individual depression. In addition, the residence type plays a moderating role between economic development and weak ties (ß=0.193, p<0.001). That is, living in urban areas would introduce the higher the level of weak ties. CONCLUSIONS: Higher economic development is largely conducive to alleviating the degrees of depression, weak ties play a mediating role between economic development and depression, and residence types exert a positive moderating effect on the economic development and weak ties.


Assuntos
Depressão , Desenvolvimento Econômico , Humanos , Estudos Longitudinais , Depressão/epidemiologia , Estudos Transversais , China/epidemiologia
14.
Artigo em Inglês | MEDLINE | ID: mdl-37204942

RESUMO

Benefiting from the independence of the vortex radius on the topological charge (TC), the perfect acoustic-vortex (PAV) with an angular phase gradient exhibits important perspectives in acoustic applications. However, the practical implementation is still restricted by the limited accuracy and flexibility of the phase control for large-scaled source arrays. An applicable scheme of constructing PAVs by the spatial Fourier transform of quasi-Bessel AV (QB-AV) beams is developed using the simplified ring array of sectorial transducers. The principle of PAV construction is derived based on the phase modulation of the Fourier and saw-tooth lenses. Numerical simulations and experimental measurements are carried out for the ring array with the continuous and discrete phase spirals. The construction of PAVs is demonstrated by the annuli at an almost identical peak pressure with the vortex radius independent of the TC. The vortex radius is proved to increase linearly with the increase of the rear focal length and the radial wavenumber, which are determined by the curvature radii and the acoustic refractive index of the Fourier lens and the bottom angle of the saw-tooth lens, respectively. The improved PAV with a more continuous high-pressure annulus and lower concentric disturbances can be constructed by the ring array of more sectorial sources and the Fourier lens of a bigger radius. The favorable results demonstrate the feasibility of constructing PAVs by the Fourier transform of QB-AV beams and provide an implementable technology in the fields of acoustic manipulation and communication.


Assuntos
Acústica , Transdutores , Análise de Fourier
15.
Clin Pediatr (Phila) ; 62(11): 1385-1389, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-36908098

RESUMO

Acute focal bacterial nephritis (AFBN) is a kidney disease characterized by a localized bacterial infection that manifests as an inflammatory mass. Most children with AFBN have nonspecific symptoms including fever, vomiting, and abdominal discomfort, and some develop neurological symptoms such as meningeal irritation, unconsciousness, and seizures as their condition worsens. This was 2 cases of AFBN with central nervous system manifestations in children, and we analyzed its possible mechanisms of the clinical and radiographic features. We experience 2 very unusual cases of AFBN which were linked to central nervous system abnormalities. A 6-year-old boy with AFBN and clinically moderate ncephalitis/encephalopathy with a reversible splenial lesion (MERS) presented with neurological symptoms, including unconsciousness and convulsions. The second case involved an 8-year-old child with AFBN-associated acute encephalopathy who exhibited neurological symptoms, including unconsciousness. According to previous research, AFBN is linked to central nervous system impairment. As a result, when a clinician meets a patient with an inexplicable fever caused by a neurological condition, he should pay attention to this diagnosis of AFBN and follow it in the abdominal graph.


Assuntos
Infecções Bacterianas , Encefalopatias , Nefrite , Masculino , Criança , Humanos , Nefrite/diagnóstico , Nefrite/microbiologia , Nefrite/patologia , Sistema Nervoso Central/patologia , Encefalopatias/complicações , Infecções Bacterianas/complicações , Convulsões , Febre/etiologia , Inconsciência/complicações , Imageamento por Ressonância Magnética
16.
Ultrason Sonochem ; 94: 106312, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36731283

RESUMO

Phase-changeable contrast agents have been proposed as a next-generation ultrasound contrast agent over conventional microbubbles given its stability, longer circulation time and ability to extravasate. Safe vaporization of nanodroplets (NDs) plays an essential role in the practical translation of ND applications in industry and medical therapy. In particular, the exposure parameters for initializing phase change as well as the site of phase change are concerned to be controlled. Compared to the traditional optical vaporization or acoustic droplet vaporization, this study exhibited the potential of using simultaneous, single burst laser and ultrasound incidence as a means of activating phase change of NDs to generate cavitation nuclei with reduced fluence and sound pressure. A theoretical model considering the laser heating, vapor cavity nucleation and growth was established, where qualitative agreement with experiment findings were found in terms of the trend of combined exposure parameters in order to achieve the same level of vaporization outcome. The results indicate that using single burst laser pulse and 10-cycle ultrasound might be sufficient to lower the exposure levels under FDA limit for laser skin exposure and ultrasound imaging. The combination of laser and ultrasound also provides temporal and spatial control of ND vaporization and cavitation nucleation without altering the sound field, which is beneficial for further safe and effective applications of phase-changeable NDs in medical, environmental, food processing and other industrial areas.


Assuntos
Acústica , Som , Volatilização , Ultrassonografia , Meios de Contraste , Lasers , Microbolhas
17.
Neurosci Res ; 192: 26-36, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36731541

RESUMO

The inevitability of age-related degeneration makes research on degradation mitigation attractive to humans, while exercise is considered an effective means due to its powerful impact on life and health. Caenorhabditis elegans is a model animal with a short life cycle and is widely used in health and aging studies. In this work, ultrasonic stimuli in the form of surface acoustic waves (SAWs) were used to induce behavioral activities in worms. As the worms grew, ultrasound-elicited behavioral responses started to decrease in the early adulthood stage. However, this situation was significantly ameliorated when ultrasonic training sessions at an effective acoustic pressure of 1.1 MPa were performed four times per day for 5 or 7 days, while ultrasonic responses in trained nematodes were stronger than those in untrained ones. These results suggest that long-term ultrasonic training might positively intervene in aging-related degeneration. Besides, it was found that exercise driven by long-term ultrasonic training had insignificant effects on the lifespan of worms. A preliminary exploration of the neural mechanisms underlying the sensation of SAWs was also conducted. The results show that, apart from touch receptor neurons (TRNs), polymodal nociceptors FLP and PVD neurons may also be involved in the perception of ultrasound in C. elegans. The results of this study may inspire related studies on other animals or humans.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Humanos , Adulto , Caenorhabditis elegans/metabolismo , Ultrassom , Envelhecimento , Proteínas de Caenorhabditis elegans/metabolismo , Células Receptoras Sensoriais/metabolismo
18.
Med Phys ; 50(5): 3076-3091, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36815305

RESUMO

BACKGROUND: As a novel non-invasive multi-physics imaging methodology, the magneto-acousto-electrical (MAE) technology is capable of detecting electric conductivity changes for biological tissues, exhibiting prosperous perspectives in medical applications. However, the acoustic beam was often simplified to a straight line or a focused one, being perpendicular to layered boundaries of tissues in previous studies. Linear-scanning measurements were carried out to reconstruct B-mode MAE images for layered models without considering the radiation pattern of transducers. Obvious image distortions in both shape and brightness were observed in experiments without any reasonable explanation. PURPOSE: This study aims to establish a general physical model for MAE measurements and solve the problem of B-mode image distortion, and hence provide theoretical and technical supports for the improvement of MAE imaging in practical applications. METHODS: By considering the radiation pattern of actual transducers and the inclined angle of electric conductivity boundaries, a general principal of MAE measurements applicable for objects of arbitrary shapes is proposed based on the theories of acoustic radiation, Hall Effect and electrical detection. The influences of inclined conductivity boundaries and transducer directivities are numerically analyzed with Matlab programming and also demonstrated by experimental measurements. To evaluate the degree of B-mode image distortion, the deformation length (3 dB amplitude decrease) of approximate straight lines for a circular model is defined as L = dtan(ßm /2), with d and ßm being the measurement distance and the half radiation angle of the main-lobe, respectively. The rotary-scanning-based MAE tomography (MAET) is employed to reduce the image distortion, and the rotation angle step is further optimized based on the criterion of the boundary radius fluctuation coefficient <0.01 mm. RESULTS: The experimental results of MAE signals and B-mode images as well as MAETs show good agreements with simulations. It is demonstrated that, as the increase of the inclined angle, the MAE decreases rapidly with an extended time interval and reaches the 20 dB amplitude decrease when the angle exceeds 12°. Meanwhile, the deformation length of B-mode MAE imaging increases with the increase of the radiation angle for the transducer with a weaker radiation pattern, and hence results in a more serious image distortion. A smaller rotation angle step should be adopted to the MAET system with a longer deformation length, and the optimized maximum angle step of 12° is also achieved for the omnidirectional radiation of point sources with a long deformation length. CONCLUSION: The image distortion is originated from the amplitude decrease, the time shift and the time interval expansion of MAE signals introduced by the deformation length and the incident angle. The favorable results demonstrate that the fast high-resolution imaging can be accomplished by the minimum rotations of the rotary-scanning-based MAET using an actual transducer, and also provide an optimized scheme for the rotary-based MAET without scanning using a linear array of point sources.


Assuntos
Algoritmos , Tomografia , Tomografia/métodos , Eletricidade , Condutividade Elétrica , Acústica , Imagens de Fantasmas
19.
Pediatr Res ; 94(1): 268-274, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36539574

RESUMO

BACKGROUND: The effect of recombinant human GH (rhGH) in Chinese children with chronic kidney disease (CKD) is unclear. METHODS: This was a 52-week, multicenter, randomized, open-label, negative-controlled phase 3 study. Prepubertal subjects were randomized 1:1 to either daily subcutaneous injections of rhGH 0.05 mg/kg/day or no treatment for 52 weeks. RESULTS: A total of 68 subjects with a mean age of 7.8 ± 3.27 years were enrolled. At week 52, the height standard deviation score (HT-SDS) in the treated group increased by 0.75 ± 0.58, which was significantly higher compared with 0.17 ± 0.47 in the untreated group (least squares mean 0.58, 95% confidence interval, 0.32-0.84; P < 0.001). At week 52, significant improvements were observed in other growth parameters (height velocity [P < 0.001]), insulin-like growth factor 1 (IGF-1) SDS [P < 0.001], IFG-1/insulin-like growth factor binding protein-3 molar ratio [P < 0.001], and height [P < 0.001]) compared with the untreated control. Seven patients reported treatment-related adverse events (TRAEs) and most TRAEs were mild in severity. Most subjects recovered without further intervention. CONCLUSIONS: Daily rhGH for 52 weeks in children with CKD-induced growth retardation significantly improved HT-SDS and other growth parameters without compromising safety. IMPACT: The efficacy and safety of growth hormone (GH) therapy in Chinese children with chronic kidney disease (CKD) are unclear. This study found that giving short stature Chinese children with CKD daily recombinant human growth hormone (rhGH) for 52 weeks improved growth parameters without compromising safety. This study's information can give physicians the confidence to treat these patients in their clinical practice.


Assuntos
Hormônio do Crescimento Humano , Insuficiência Renal Crônica , Humanos , Criança , Pré-Escolar , População do Leste Asiático , Transtornos do Crescimento/tratamento farmacológico , Hormônio do Crescimento Humano/uso terapêutico , Hormônio do Crescimento Humano/farmacologia , Hormônio do Crescimento/farmacologia , Insuficiência Renal Crônica/tratamento farmacológico , Fator de Crescimento Insulin-Like I/metabolismo , Proteínas Recombinantes/uso terapêutico , Proteínas Recombinantes/farmacologia , Estatura
20.
Research (Wash D C) ; 6: 0280, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38434241

RESUMO

With unlimited topological modes in mathematics, the fractional orbital angular momentum (FOAM) demonstrates the potential to infinitely increase the channel capacity in acoustic-vortex (AV) communications. However, the accuracy and stability of FOAM recognition are still limited by the nonorthogonality and poor anti-interference of fractional AV beams. The popular machine learning, widely used in optics based on large datasets of images, does not work in acoustics because of the huge engineering of the 2-dimensional point-by-point measurement. Here, we report a strategy of phase-dislocation-mediated high-dimensional fractional AV communication based on pair-FOAM multiplexing, circular sparse sampling, and machine learning. The unique phase dislocation corresponding to the topological charge provides important physical guidance to recognize FOAMs and reduce sampling points from theory to practice. A straightforward convolutional neural network considering turbulence and misalignment is further constructed to achieve the stable and accurate communication without involving experimental data. We experimentally present that the 32-point dual-ring sampling can realize the 10-bit information transmission in a limited topological charge scope from ±0.6 to ±2.4 with the FOAM resolution of 0.2, which greatly reduce the divergence in AV communications. The infinitely expanded channel capacity is further verified by the improved FOAM resolution of 0.025. Compared with other milestone works, our strategy reaches 3-fold OAM utilization, 4-fold information level, and 5-fold OAM resolution. Because of the extra advantages of high dimension, high speed, and low divergence, this technology may shed light on the next-generation AV communication.

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