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1.
Bull Exp Biol Med ; 177(1): 98-103, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38963599

RESUMO

We examined the effects of elevated temperatures and biocides on survivability of food isolates of Cronobacter spp. (C. sakazakii) and concomitant enterobacteriaceae obtained in microbiological control of infant nutrition products. Increased resistance of certain strains of Cronobacter, Enterobacter cloacae, and Pantoea spp. to thermal processing was revealed. Salmonella, Pantoea, and Cronobacter bacteria were least sensitive to antimicrobial action of chlorine-containing agents. The above properties varied in the strains of the same species. Specifically, only two of three examined isolates of Cronobacter spp. demonstrated lower sensitivity to heat in comparison with the enterobacterial test-cultures of other species.


Assuntos
Cloro , Cronobacter , Desinfetantes , Microbiologia de Alimentos , Desinfetantes/farmacologia , Cronobacter/efeitos dos fármacos , Cronobacter/isolamento & purificação , Cloro/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Temperatura Alta , Humanos , Cronobacter sakazakii/efeitos dos fármacos , Cronobacter sakazakii/isolamento & purificação , Testes de Sensibilidade Microbiana , Salmonella/efeitos dos fármacos , Salmonella/isolamento & purificação , Enterobacter cloacae/efeitos dos fármacos , Enterobacter cloacae/isolamento & purificação
2.
Opt Express ; 32(8): 13761-13768, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38859337

RESUMO

Bose-Einstein condensation occurs at an appropriate density of bosonic particles, depending on their mass and temperature. The transition from the semiclassical paradigm of spin waves to the magnon Bose-Einstein condensed state (mBEC) was obtained experimentally with increasing magnon density. We used the Faraday rotation effect to study the spatial distribution of the magnon density and phase far from their excitation region. A coherent magnetization precession was observed throughout the sample, which indicates the formation of a magnon BEC. It is shown that this result under experimental conditions goes beyond the applicability of the Landau-Lifshitz-Gilbert semiclassical theory.

3.
Nature ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862026

RESUMO

Human spaceflight has historically been managed by government agencies, such as the NASA Twins Study1, but new commercial spaceflight opportunities have opened spaceflight to a broader population. In 2021, the SpaceX Inspiration4 mission launched the first-ever all civilian crew to low Earth orbit, which included the youngest American astronaut (age 29), novel in-flight experimental technologies (handheld ultrasound imaging, smartwatch wearables, and immune profiling), ocular alignment measurements, and new protocols for in-depth, multi-omic molecular and cellular profiling. Here we report the primary findings from the 3-day spaceflight mission, which induced a broad range of physiological and stress responses, neurovestibular changes indexed by ocular misalignment, and altered neurocognitive functioning, some of which match long-term spaceflight2, but almost all of which did not differ from baseline (pre-flight) after return to Earth. Overall, these preliminary civilian spaceflight data suggest that short-duration missions do not pose a significant health risk, and moreover present a rich opportunity to measure the earliest phases of adaptation to spaceflight in the human body at anatomical, cellular, physiologic, and cognitive levels. Finally, these methods and results lay the foundation for an open, rapidly expanding biomedical database for astronauts3, which can inform countermeasure development for both private and government-sponsored space missions.

4.
Phys Rev Lett ; 132(21): 211803, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38856264

RESUMO

We report the first search for dark sectors performed at the NA64 experiment employing a high energy muon beam and a missing energy-momentum technique. Muons from the M2 beamline at the CERN Super Proton Synchrotron with a momentum of 160 GeV/c are directed to an active target. The signal signature consists of a single scattered muon with momentum <80 GeV/c in the final state, accompanied by missing energy, i.e., no detectable activity in the downstream calorimeters. For a total dataset of (1.98±0.02)×10^{10} muons on target, no event is observed in the expected signal region. This allows us to set new limits on the remaining (m_{Z^{'}},g_{Z^{'}}) parameter space of a new Z^{'} (L_{µ}-L_{τ}) vector boson which could explain the muon (g-2)_{µ} anomaly. Additionally, our study excludes part of the parameter space suggested by the thermal dark matter relic abundance. Our results pave the way to explore dark sectors and light dark matter with muon beams in a unique and complementary way to other experiments.

5.
Neurochem Int ; : 105791, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38880231

RESUMO

Long-term studies have confirmed a causal relationship between the development of neurodegenerative processes and vitamin B1 (thiamine) deficiency. However, the biochemical mechanisms underlying the high neurotropic activity of thiamine are not fully understood. At the same time, there is increasing evidence that vitamin B1, in addition to its coenzyme functions, may have non-coenzyme activities that are particularly important for neurons. To elucidate which effects of vitamin B1 in neurons are due to its coenzyme function and which are due to its non-coenzyme activity, we conducted a comparative study of the effects of thiamine and its derivative, 3-decyloxycarbonylmethyl-5-(2-hydroxyethyl)-4-methyl-1,3-thiazolium chloride (DMHT), on selected processes in synaptosomes. The ability of DMHT to effectively compete with thiamine for binding to thiamine-binding sites on the plasma membrane of synaptosomes and to participate as a substrate in the thiamine pyrophosphokinase reaction was demonstrated. In experiments with rat brain synaptosomes, unidirectional effects of DMHT and thiamine on the activity of the pyruvate dehydrogenase complex (PDC) and on the incorporation of radiolabeled [2-14C]pyruvate into acetylcholine were demonstrated. The observed effects of thiamine and DMHT on the modulation of acetylcholine synthesis can be explained by suggesting that both compounds, which interact in cells with enzymes of thiamine metabolism, are phosphorylated and exert an inhibitory/activating effect (concentration-dependent) on PDC activity by affecting the regulatory enzymes of the complex. Such effects were not observed in the presence of structural analogs of thiamine and DMHT without a 2-hydroxyethyl substituent at position 5 of the thiazolium cycle. The effect of DMHT on the plasma membrane Ca-ATPase was similar to that of thiamine. At the same time, DMHT showed high cytostatic activity against neuroblastoma cells.

7.
Zhonghua Yi Xue Za Zhi ; 104(23): 2160-2166, 2024 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-38871474

RESUMO

Objective: To investigate the clinical and genetic mutation characteristics of patients with primary hemophagocytic lymphohistiocytosis (HLH) and their impact on prognosis. Methods: Sixty-three primary HLH patients with complete medical records admitted and diagnosed at Beijing Friendship Hospital of Capital Medical University from January 2013 to December 2022 were selected. The patients' clinical and laboratory features, genetic and rapid immunological indicator characteristics, treatment outcomes and prognosis were retrospectively analyzed. Follow-up was up to June 30, 2023, with a median follow-up time [M (Q1, Q3)] of 47 (21, 76) months. Overall survival was analyzed using Kaplan-Meier survival curve, and prognostic factors were analyzed using Cox proportional hazards regression model. Results: Sixty-three primary HLH patients included 35 males and 28 females, with a median age [M (Q1, Q3)] of 17 (7, 27) years. Clinical manifestations at the initial diagnosis mainly included fever (93.7%, 59/63), splenomegaly (87.3%, 55/63), hemophagocytosis (65.1%, 41/63), hepatomegaly (52.4%, 33/63) and central nervous system (CNS) involvement (38.1%, 24/63). A total of 39 patients (61.9%) were diagnosed with EB virus (EBV) infection at initial diagnosis.PRF1 and UNC13D gene mutations were the most common mutations, and the highest frequency mutation site in the PRF1 gene was c.1349C>T, and that of UNC13D gene was c.2588G>A. A total of 76.2% (48/63) of patients had reduced activity of natural killer (NK) cells. Cytotoxic cell degranulation function was impaired or absent in 52.7% (29/55) of patients, of which 79.2% (19/24) of patients with primary HLH with defects in degranulation-related genes had impaired degranulation function. The 1-year and 3-year overall survival rates were 74.8% and 66.7%, respectively. Cox multivariate analysis suggested that peripheral blood EBV≥10 000 copies/ml (HR=3.523, 95%CI: 1.418-8.757, P=0.007) was the risk factor for prognosis. Conclusions: The main clinical manifestations of primary HLH patients at the initial diagnosis include fever, splenomegaly, hemophagocytosis, hepatomegaly, and CNS involvement. PRF1 and UNC13D are the most commonly mutated genes. High copy number EBV infection in peripheral blood is the risk factor for prognosis.


Assuntos
Linfo-Histiocitose Hemofagocítica , Mutação , Humanos , Linfo-Histiocitose Hemofagocítica/genética , Linfo-Histiocitose Hemofagocítica/diagnóstico , Masculino , Prognóstico , Feminino , Estudos Retrospectivos , Adolescente , Criança , Adulto , Adulto Jovem , Perforina/genética
8.
Zhonghua Yi Xue Za Zhi ; 104(23): 2173-2178, 2024 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-38871476

RESUMO

Objective: To investigate the efficacy and safety of intravenous thrombolysis with Tenecteplase (TNK) in patients with post-awakening branch atheromatous disease (BAD). Methods: A retrospective collection was conducted on 178 patients with post-awakening BAD admitted to the Stroke Centre of Zhengzhou People's Hospital from January 2017 to June 2023, who had a mismatch in DWI/FLAIR on magnetic resonance imaging. The patients were divided into thrombolysis group (60 patients) and control group (118 patients) according to whether or not they were applied to intravenous thrombolysis by TNK. Propensity score matching (PSM) was used to pair and balance the confounding factors at 1∶1 between the two groups, and the 90-d long-term prognosis of the patients was assessed using the modified Rankin Scale (mRS) and the Barthel Index (BI). The National Institutes of Health Stroke Scale (NIHSS) score was used to compare the early neurological changes between the two groups.The differences in clinical outcomes were compared between the two groups. Results: Fifty-two pairs of patients, 65 males and 39 females, aged (60±9) years, were successfully matched by PSM. The thrombolysis group had lower NIHSS score than that of the control group at 24 h, 7 d, 14 d after treatment or at discharge [3(2, 5) vs 4(3, 7), 3(2, 5) vs 4(3, 5), and 2(1, 4) vs 3(2, 4)], and shorter hospital stay than that of the control group [9(7, 12) d vs 11(9, 13) d], and at the same time, the thrombolysis group was less likely to experience early neurological deterioration (END) [9.6% (5/52) vs 28.9% (15/52)], and the proportion of 90 d mRS≤1, mRS≤2, and BI scores were higher than those in the control group [63.5% (33/52) vs 30.8% (16/52), 82.7% (43/52) vs 59.6% (31/52), and (91±8) points vs (82±8) points ], all differences were statistically significant (P<0.05). The percentage of mRS≥4 points was higher in the control group than that in the thrombolysis group [23.1% (12/52) vs 7.7% (4/52)]. One case of intracranial haemorrhage occurred in the thrombolysis group, and 1 case in the control group died of pulmonary infection within 90 d of follow-up, with a case-fatality rate of 1.9% (1/52). Conclusion: In the patients with post-awakening BAD screened by MRI, TNK intravenous thrombolysis can significantly reduce the risk of END, improving long-term prognosis and has a high safety.


Assuntos
Fibrinolíticos , Tenecteplase , Terapia Trombolítica , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tenecteplase/administração & dosagem , Tenecteplase/uso terapêutico , Fibrinolíticos/uso terapêutico , Fibrinolíticos/administração & dosagem , Administração Intravenosa , Resultado do Tratamento , Acidente Vascular Cerebral/tratamento farmacológico , Idoso , Ativador de Plasminogênio Tecidual/uso terapêutico , Ativador de Plasminogênio Tecidual/administração & dosagem , Prognóstico , Pontuação de Propensão
9.
Phys Rev E ; 109(4-2): 045205, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38755824

RESUMO

To find a way to control the electron-bunching process and the bunch-emitting directions when an ultraintense, linearly polarized laser pulse interacts with a nanoscale target, we explored the mechanisms for the periodical generation of relativistic attosecond electron bunches. By comparing the simulation results of three different target geometries, the results show that for nanofoil target, limiting the transverse target size to a small value and increasing the longitudinal size to a certain extent is an effective way to improve the total electron quantity in a single bunch. Then the subfemtosecond electronic dynamics when an ultrashort ultraintense laser grazing propagates along a nanofoil target was analyzed through particle-in-cell simulations and semiclassical analyses, which shows the detailed dynamics of the electron acceleration, radiation, and bunching process in the laser field. The analyses also show that the charge separation field produced by the ions plays a key role in the generation of electron bunches, which can be used to control the quantity of the corresponding attosecond radiation bunches by adjusting the length of the nanofoil target.

10.
Vestn Otorinolaringol ; 89(2): 109-112, 2024.
Artigo em Russo | MEDLINE | ID: mdl-38805473

RESUMO

The article presents a case of pharyngeal dysphagia and obstructive sleep apnea syndrome caused by degenerative-dystrophic changes in the cervical spine with the formation of large cervical osteophytes at the C3-C6 level. Osteophytes caused deformation of the posterior wall of the hypopharynx and narrowing of its lumen by 20-25% from the level of the arytenoid cartilages to the upper parts of the epiglottis. CT scan also showed the intervertebral disc heights lost, as well as osteophytes at the posterolateral margins of the vertebral bodies (disc osteophyte complex). Osteosclerosis in combination with facet arthrosis caused spinal and foraminal stenosis.


Assuntos
Vértebras Cervicais , Transtornos de Deglutição , Humanos , Vértebras Cervicais/diagnóstico por imagem , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/fisiopatologia , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/fisiopatologia , Apneia Obstrutiva do Sono/complicações , Apneia Obstrutiva do Sono/etiologia , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
12.
Zhonghua Liu Xing Bing Xue Za Zhi ; 45(4): 559-565, 2024 Apr 10.
Artigo em Chinês | MEDLINE | ID: mdl-38678353

RESUMO

Objective: To understand the awareness rate of mpox knowledge and related factors among men who have sex with men (MSM) in China. Methods: The survey was conducted among men aged ≥18 years who had sex with men in the past year, using the convenience sampling method. The estimated sample size was 4 312. With the assistance of social organizations of MSM in 30 provinces in China, an online questionnaire survey was conducted using anonymous self-designed questionnaires powered by www.wjx.cn during 10-14 August 2023 to collect information on socio-demographic characteristics, awareness of mpox knowledge, travel history, and sexual behaviors of the respondents. The software SAS 9.4 was used for statistical analysis. Results: There were 7 725 respondents, and the age of the respondents was (31.6±9.0) years. The results revealed that the awareness rate of mpox knowledge was 50.1% (3 872/7 725). The main routes to acquire mpox knowledge were mainly new media, including WeChat, Weibo, TikTok, and Blued social software (88.4%,6 827/7 725), while official media report was the most trusted way to acquire related knowledge (79.3%,6 129/7 725). Multivariate logistic regression analysis revealed that the factors indicated a higher awareness rate of mpox knowledge, including living in the western region or the eastern region, people were over 26 years old in early adulthood and midlife, college-educated or with higher degrees, living in towns or urban periphery, being in homosexual or in bisexual relationships, 1-5 homosexual times/months in the past 3 months, knowing their HIV infection status, paying attention to mpox knowledge very often, occasionally or rarely, and convenient ways to acquire mpox knowledge from new media and social organizations. Conclusions: The awareness rate of mpox knowledge was low among MSM in China. Efforts should be made to improve the awareness rate of mpox knowledge among those who are young, less educated, or sexually active, with targeted health education via new media and social organizations.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Homossexualidade Masculina , Comportamento Sexual , Humanos , Masculino , Homossexualidade Masculina/estatística & dados numéricos , Homossexualidade Masculina/psicologia , China , Inquéritos e Questionários , Adulto , Comportamento Sexual/estatística & dados numéricos , Adulto Jovem
13.
Opt Express ; 32(6): 9495-9511, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571183

RESUMO

We study the properties of bound states in waveguide-QED systems consisting of multiple giant atoms coupled to a coupled-resonator waveguide. Based on the general analytical expressions for these states and the corresponding energy spectra, we analyze in detail the threshold conditions for the appearance of bound states and the photon-mediated interactions between dressed atoms for different configurations. In addition, when multiple giant atoms are coupled to the waveguide, different types of interacting atomic chain can be obtained by manipulating the coupling configurations. Accordingly, the energy spectra of the bound states form metaband structures in the photonic band gaps. This makes the system a useful platform for quantum simulation and quantum information processing.

14.
Zhonghua Liu Xing Bing Xue Za Zhi ; 45(3): 325-330, 2024 Mar 10.
Artigo em Chinês | MEDLINE | ID: mdl-38514307

RESUMO

Objective: To explore the prospective associations between physical activity and incident ischemic stroke in adults. Methods: Data of China Kadoorie Biobank study in Tongxiang of Zhejiang were used. After excluding participants with cancers, strokes, heart diseases and diabetes at baseline study, a total of 53 916 participants aged 30-79 years were included in the final analysis. The participants were divided into 5 groups according to the quintiles of their physical activity level. Cox proportional hazard regression models was used to calculate the hazard ratios (HR) for the analysis on the association between baseline physical activity level and risk for ischemic stroke. Results: The total physical activity level in the participants was (30.63±15.25) metabolic equivalent (MET)-h/d, and it was higher in men [(31.04±15.48) MET-h/d] than that in women [(30.33±15.07) MET-h/d] (P<0.001). In 595 526 person-years of the follow-up (average 11.4 years), a total of 1 138 men and 1 082 women were newly diagnosed with ischemic stroke. Compared to participants with the lowest physical activity level (<16.17 MET-h/d), after adjusting for socio-demographic factors, lifestyle, BMI, waist circumference, and SBP, the HRs for the risk for ischemic stroke in those with moderate low physical activity level (16.17-24.94 MET-h/d), moderate physical activity level (24.95-35.63 MET-h/d), moderate high physical activity level (35.64-43.86 MET-h/d) and the highest physical activity level (≥43.87 MET-h/d) were 0.93 (95%CI: 0.83-1.04), 0.87 (95%CI: 0.76-0.98), 0.82 (95%CI: 0.71-0.95) and 0.76 (95%CI: 0.64-0.89), respectively. Conclusion: Improving physical activity level has an effect on reducing the risk for ischemic stroke.


Assuntos
Diabetes Mellitus , AVC Isquêmico , Acidente Vascular Cerebral , Adulto , Masculino , Humanos , Feminino , Estudos Prospectivos , Acidente Vascular Cerebral/epidemiologia , Exercício Físico , China/epidemiologia , Fatores de Risco
15.
Zhonghua Liu Xing Bing Xue Za Zhi ; 45(3): 353-357, 2024 Mar 10.
Artigo em Chinês | MEDLINE | ID: mdl-38514311

RESUMO

Objective: To understand the baseline viral load (VL) of newly reported HIV- infected patients before antiretroviral therapy and related factors in Tianjin. Methods: Data were obtained from the China Disease Control and Prevention Information System, and the study subjects were HIV-infected patients before the first antiretroviral therapy in Tianjin from 2019 to 2022, and the information about their socio-demographic characteristics, baseline CD4+T lymphocyte (CD4) counts before antiretroviral therapy and baseline VL test results were collected, the baseline high VL was defined as ≥100 000 copies/ml. The effect of different factors on viral load were analyzed. Software SPSS 24.0 was used for statistical analysis. Results: A total of 1 296 newly reported HIV-infected patients were included in the study, in whom 15.89% (206/1 296) had high baseline VL, and multifactorial logistic regression analysis showed that those with history of STD (aOR=1.45, 95%CI:1.00-2.08) were more likely to have high baseline VL. Compared with those with baseline CD4 counts <200 cells/µl, those with baseline CD4 counts 200-350 cells/µl (aOR=0.40, 95%CI: 0.27-0.57), 351-500 cells/µl (aOR=0.32, 95%CI: 0.20-0.49), and >500 cells/µl (aOR=0.30, 95%CI: 0.18-0.49) were less likely to have high baseline VL. Conclusions: The proportion of HIV-infected patients with high baseline VL before antiretroviral therapy was low in Tianjin during 2019-2022. History of STD and baseline CD4 counts <200 cells/µl were associated with high baseline VL in HIV-infected patients, to which close attention needs to be paid in AIDS prevention and control.


Assuntos
Síndrome da Imunodeficiência Adquirida , Infecções por HIV , Humanos , Carga Viral , Contagem de Linfócito CD4 , China/epidemiologia , Terapia Antirretroviral de Alta Atividade
18.
Vestn Otorinolaringol ; 89(1): 42-44, 2024.
Artigo em Russo | MEDLINE | ID: mdl-38506025

RESUMO

The article presents a case of chronic odontogenic maxillary sinusitis and the results of its surgical treatment. The cause of the sinusitis, confirmed by the results of X-ray and pathohistological studies, was an inflammatory process affecting the bone tissue around the implant, installed in the place of the upper first molar which was accompanied by the development of an oroantral fistula. During the surgical intervention, the communication between the oral cavity and the maxillary sinus was eliminated, and the implant with the abutment, which was entirely in its cavity, was also removed.


Assuntos
Implantes Dentários , Sinusite Maxilar , Humanos , Sinusite Maxilar/diagnóstico , Sinusite Maxilar/etiologia , Sinusite Maxilar/cirurgia , Implantes Dentários/efeitos adversos , Seio Maxilar/diagnóstico por imagem , Seio Maxilar/cirurgia , Fístula Bucoantral/diagnóstico , Fístula Bucoantral/etiologia , Fístula Bucoantral/cirurgia , Doença Crônica
19.
Zh Vopr Neirokhir Im N N Burdenko ; 88(1): 109-114, 2024.
Artigo em Russo | MEDLINE | ID: mdl-38334738

RESUMO

The main problem in microsurgical resection of spinal cord tumors is excessive surgical aggression. The last one often leads to unsatisfactory clinical and neurological outcomes. Laser fluorescence spectroscopy is a modern neurosurgical approach to distinguish tumor boundaries even if standard visible fluorescence techniques are ineffective. OBJECTIVE: To evaluate the effectiveness of laser fluorescence spectroscopy alone or in combination with visual 5-ALA fluorescence for improvement of safety and quality of resection, as well as intraoperative diagnosis. MATERIAL AND METHODS: Searching for literature data was carried out in accordance with the PRISMA recommendations. The authors reviewed articles independently of each other. These data were systematized. RESULTS: Laser fluorescence spectroscopy is valuable to identify fragments of intramedullary ependyomas in 86% of cases, while visual fluorescence only in 81% of cases. Advisability of this technique for low-grade astrocytomas is still unclear and requires further study. Its effectiveness is 87.5% for extramedullary meningiomas. Neuromas do not accumulate 5-ALA. In addition, this method can be used to determine the boundaries of intradural metastatic lesions. CONCLUSION: 5-ALA fluorescence is a safe and useful intraoperative method for identifying tumor tissue and resection margins in patients with intramedullary or infiltrative extramedullary spinal cord tumors. Visual fluorescence combined with laser spectroscopy is a perspective method for intraoperative visualization of tumor remnants. This approach can improve safety and postoperative outcomes while maintaining resection quality.


Assuntos
Neoplasias da Medula Espinal , Neoplasias da Coluna Vertebral , Humanos , Neoplasias da Coluna Vertebral/cirurgia , Espectrometria de Fluorescência , Neoplasias da Medula Espinal/diagnóstico por imagem , Neoplasias da Medula Espinal/cirurgia , Procedimentos Neurocirúrgicos/métodos , Lasers
20.
Bull Exp Biol Med ; 176(3): 399-402, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38342809

RESUMO

A morphological analysis of the liver of Wistar rats was performed 2 months after a single intravenous injection of porous silicon particles of different sizes (60-80, 250-300, and 500-600 nm; 2 mg/ml, 1 ml). Histological, immunohistochemical, and electron microscopic methods showed the development of CD68+ granulomas in all experimental groups. Injection of 60-80-nm porous silicon particles led to the formation of single large granulomas (>2000 µm2), while 500-600-nm nanoparticles caused the formation of numerous smaller granulomas. The mechanism of involution of granulomas by apoptosis of Kupffer cells and the absence of subsequent connective tissue remodeling of the organ tissue is shown.


Assuntos
Fígado , Silício , Ratos , Animais , Ratos Wistar , Fígado/patologia , Granuloma/induzido quimicamente , Granuloma/patologia , Células de Kupffer
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