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1.
Front Bioeng Biotechnol ; 12: 1390337, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38707496

RESUMO

Objective: This study aims to develop and evaluate the biocompatibility and osteogenic potential of a novel injectable strontium-doped hydroxyapatite bone-repair material. Methods: The properties of strontium-doped hydroxyapatite/chitosan (Sr-HA/CS), hydroxyapatite/chitosan (HA/CS) and calcium phosphate/chitosan (CAP/CS) were assessed following their preparation via physical cross-linking and a one-step simplified method. Petri dishes containing Escherichia coli and Staphylococcus epidermidis were inoculated with the material for in vitro investigations. The material was also co-cultured with stem cells derived from human exfoliated deciduous teeth (SHEDs), to assess the morphology and proliferation capability of the SHEDs, Calcein-AM staining and the Cell Counting Kit-8 assay were employed. Osteogenic differentiation of SHEDs was determined using alkaline phosphatase (ALP) staining and Alizarin Red staining. For in vivo studies, Sr-HA/CS was implanted into the muscle pouch of mice and in a rat model of ovariectomy-induced femoral defects. Hematoxylin-eosin (HE) staining was performed to determine the extent of bone formation and defect healing. The formation of new bone was determined using Masson's trichrome staining. The osteogenic mechanism of the material was investigated using Tartrate-resistant acid phosphatase (TRAP) staining and immunohistochemical studies. Results: X-ray diffraction (XRD) and energy-dispersive spectroscopy (EDS) showed that strontium was successfully doped into HA. The Sr-HA/CS material can be uniformly squeezed using a syringe with a 13% swelling rate. Sr-HA/CS had a significant antibacterial effect against both E. coli and S. epidermidis (p < 0.05), with a stronger effect observed against E. coli. The Sr-HA/CS significantly improved cell proliferation and cell viability in vitro studies (p < 0.05). Compared to CAP/CS and CS, Sr-HA/CS generated a substantially greater new bone area during osteoinduction experiments (p < 0.05, p < 0.001). The Sr-HA/CS material demonstrated a significantly higher rate of bone repair in the bone defeat studies compared to the CAP/CS and CS materials (p < 0.01). The OCN-positive area and TRAP-positive cells in Sr-HA/CS were greater than those in control groups (p < 0.05). Conclusion: A novel injectable strontium-doped HA bone-repair material with good antibacterial properties, biocompatibility, and osteoinductivity was successfully prepared.

2.
Org Lett ; 26(15): 3235-3240, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38557113

RESUMO

Catalytic asymmetric 1,2-allylation of aurone-derived azadienes is very difficult to achieve due to the driving force for aromatization and the greater steric hindrance of 1,2-addition compared with 1,4-addition. By taking advantage of the ability of nitrogen ligated metal complexes, we successfully demonstrated the first example of copper-catalyzed 1,2-allylation of azadienes with allylboronates for the highly enantioselective synthesis of homoallylic amines. Meanwhile, the enantioenriched 1,4-addition products could also be obtained through a subsequent 3,3-sigmatropic rearrangement of the 1,2-addition products. Extensive DFT calculations were carried out to elucidate the origins of high regioselectivity (1,2- vs 1,4-) and enantioselectivity.

3.
ACS Appl Mater Interfaces ; 16(1): 95-110, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38157482

RESUMO

Nanozymes, emerging nanomaterials for wound healing, exhibit enzyme-like activity to modulate the levels of reactive oxygen species (ROS) at wound sites. Yet, the solo regulation of endogenous ROS by nanozymes often falls short, particularly in chronic refractory wounds with complex and variable pathological microenvironments. In this study, we report the development of a multifunctional wound dressing integrating a conventional alginate (Alg) hydrogel with a newly developed biodegradable copper hydrogen phosphate (CuP) nanozyme, which possesses good near-infrared (NIR) photothermal conversion capabilities, sustained Cu ion release ability, and pH-responsive peroxidase/catalase-mimetic catalytic activity. When examining acute infected wounds characterized by a low pH environment, the engineered Alg/CuP composite hydrogels demonstrated high bacterial eradication efficacy against both planktonic bacteria and biofilms, attributed to the combined action of catalytically generated hydroxyl radicals and the sustained release of Cu ions. In contrast, when applied to chronic diabetic wounds, which typically have a high pH environment, these composite hydrogels exhibit significant angiogenic performance. This is driven by the provision of catalytically generated dissolved oxygen and a beneficial supplement of Cu ions released from the degradable CuP nanozyme. Further, a mild thermal effect induced by NIR irradiation amplifies the catalytic activities and bioactivity of Cu ions, thereby enhancing the healing process of both infected and diabetic wounds. Our study validates that the synergistic integration of photothermal effects, catalytic activity, and released Cu ions can concurrently yield high antibacterial efficiency and tissue regenerative activity, rendering it highly promising for various clinical applications in wound healing.


Assuntos
Cobre , Diabetes Mellitus , Espécies Reativas de Oxigênio , Bandagens , Alginatos , Antibacterianos/farmacologia , Hidrogéis/farmacologia , Íons , Concentração de Íons de Hidrogênio
4.
Org Lett ; 25(46): 8344-8349, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-37962415

RESUMO

A nickel-catalyzed three-component alkylarylation of alkenyl N-heteroarenes with α-bromocarboxylates and aryl boronic acids is reported. The protocol provides a new method to access a variety of N-heteroarene substituted diarylalkanes in moderate to good yields. It features mild reaction conditions, cheap nickel catalyst, readily available substrates, and broad substrate scope.

5.
Regen Biomater ; 10: rbad049, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37274616

RESUMO

The increased number of mastectomies, combined with rising patient expectations for cosmetic and psychosocial outcomes, has necessitated the use of adipose tissue restoration techniques. However, the therapeutic effect of current clinical strategies is not satisfying due to the high demand of personalized customization and the timely vascularization in the process of adipose regeneration. Here, a composite hydrogel scaffold was prepared by three-dimensional (3D) printing technology, applying gelatin methacrylate anhydride (GelMA) as printing ink and calcium silicate (CS) bioceramic as an active ingredient for breast adipose tissue regeneration. The in vitro experiments showed that the composite hydrogel scaffolds could not only be customized with controllable architectures, but also significantly stimulated both 3T3-L1 preadipocytes and human umbilical vein endothelial cells in multiple cell behaviors, including cell adhesion, proliferation, migration and differentiation. Moreover, the composite scaffold promoted vascularized adipose tissue restoration under the skin of nude mice in vivo. These findings suggest that 3D-printed GelMA/CS composite scaffolds might be a good candidate for adipose tissue engineering.

6.
Front Bioeng Biotechnol ; 11: 1158007, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36937744

RESUMO

In clinical practice, the utilization of antibiotics is still the main approach for the treatment of wound contamination, which lacks the ability to accelerate wound healing and arises the global concern of antimicrobial resistance. Plenty of alternative methods have been explored in recent years due to the fast development of material science. Here, CuO/SiO2 nanowires (CuSi NWs) with good near-infrared (NIR) photothermal conversion ability are synthesized by a one-step hydrothermal method. The as-prepared CuSi NWs possess excellent antibacterial ability against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), which could be enhanced by the assistance of mild photothermal therapy (PTT). Moreover, CuSi NWs at suitable concentrations can promote proliferation, migration, and angiogenic gene expression of human umbilical vein endothelial cells (HUVECs), exhibiting a remarkable pro-vascularization ability. The in vivo mouse infect model further proves that the CuSi NWs might be a good candidate for the treatment of infected wounds as the high antibacterial efficiency and accelerated wound healing is obtained.

7.
Tissue Eng Regen Med ; 20(5): 671-681, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36920676

RESUMO

BACKGROUND: Pathological cardiac hypertrophy is one of the main activators of heart failure. Currently, no drug can completely reverse or inhibit the development of pathological cardiac hypertrophy. To this end, we proposed a silicate ion therapy based on extract derived from calcium silicate (CS) bioceramics for the treatment of angiotensin II (Ang II) induced cardiac hypertrophy. METHODS: In this study, the Ang II induced cardiac hypertrophy mouse model was established, and the silicate ion extract was injected to mice intravenously. The cardiac function was evaluated by using a high-resolution Vevo 3100 small animal ultrasound imaging system. Wheat germ Agglutinin, Fluo4-AM staining and immunofluorescent staining was conducted to assess the cardiac hypertrophy, intracellular calcium and angiogenesis of heart tissue, respectively. RESULTS: The in vitro results showed that silicate ions could inhibit the cell size of cardiomyocytes, reduce cardiac hypertrophic gene expression, including atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and ß-myosin heavy chain (ß-MHC), decrease the content of intracellular calcium induced by Ang II. In vivo experiments in mice confirmed that intravenous injection of silicate ions could remarkably inhibit the cardiac hypertrophy and promote the formation of capillaries, further alleviating Ang II-induced cardiac function disorder. CONCLUSION: This study demonstrated that the released silicate ions from CS possessed potential value as a novel therapeutic strategy of pathological cardiac hypertrophy, which provided a new insight for clinical trials.


Assuntos
Angiotensina II , Cálcio , Cardiomegalia , Silicatos , Animais , Camundongos , Angiotensina II/efeitos adversos , Cálcio/metabolismo , Cardiomegalia/induzido quimicamente , Cardiomegalia/tratamento farmacológico , Cardiomegalia/patologia , Silicatos/uso terapêutico , Remodelação Ventricular
8.
Ultrasound Med Biol ; 49(6): 1441-1448, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36948896

RESUMO

OBJECTIVE: Lung ultrasound (LUS) has become an essential clinical tool for pulmonary evaluation. LUS has been found to induce pulmonary capillary hemorrhage (PCH) in animal models, posing a safety issue. The induction of PCH was investigated in rats, and exposimetry parameters were compared with those of a previous neonatal swine study. METHODS: Female rats were anesthetized and scanned in a warmed water bath with the 3Sc, C1-5 and L4-12t probes from a GE Venue R1 point-of-care ultrasound machine. Acoustic outputs (AOs) of sham, 10%, 25%, 50% or 100% were applied for 5-min exposures with the scan plane aligned with an intercostal space. Hydrophone measurements were used to estimate the in situ mechanical index (MIIS) at the lung surface. Lung samples were scored for PCH area, and PCH volumes were estimated. RESULTS: At 100% AO, the PCH areas were 73 ± 19 mm2 for the 3.3 MHz 3Sc probe (4 cm lung depth), 49 ± 20 mm2 (3.5 cm lung depth) or 96 ± 14 mm2 (2 cm lung depth) for the 3.0 MHz C1-5 probe and 7.8 ± 2.9 mm2 for the 7 MHz L4-12t (1.2 cm lung depth). Estimated volumes ranged from 378 ± 97 mm3 for the C1-5 at 2 cm to 1.3 ± 1.5 mm3 for the L4-12t. MIIS thresholds for PCH were 0.62, 0.56 and 0.48 for the 3Sc, C1-5 and L4-12t, respectively. CONCLUSION: Comparison between this study and previous similar research in neonatal swine revealed the importance of chest wall attenuation. Neonatal patients may be most susceptible to LUS PCH because of thin chest walls.


Assuntos
Pneumopatias , Parede Torácica , Ratos , Feminino , Animais , Suínos , Ratos Sprague-Dawley , Modelos Animais de Doenças , Pulmão/diagnóstico por imagem , Pulmão/irrigação sanguínea , Pneumopatias/etiologia , Ultrassonografia/efeitos adversos , Hemorragia/diagnóstico por imagem , Hemorragia/etiologia
9.
J Ultrasound Med ; 42(8): 1689-1698, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36723246

RESUMO

OBJECTIVES: Lung ultrasound (LUS) is a powerful and accessible clinical tool for pulmonary diagnosis, but risk of pulmonary capillary hemorrhage (PCH) presents a safety issue. The dependence of PCH in a rat model of LUS was evaluated for image frames-per-second (fps) and associated on-screen Mechanical Index (MIOS ) and Thermal Index (TI). METHODS: A Philips iE33 machine with L15-7io probe was used to scan anesthetized rats in a warmed water bath. B mode was applied at 9 MHz with settings of 34, 61 and 118 fps. After 2 minutes of exposure at an MIOS setting, samples were obtained for assessment of PCH areas on the lung surface. Ultrasound parameters were measured to determine the in situ MIIS at the lung surface. RESULTS: The PCH trend counter-intuitively decreased with increasing fps, with areas of 19.5 mm2 for 34 fps (MIOS  = 1.0, TI = 0.8, 4080 images), 9.6 mm2 at 61 fps (MIOS  = 1.0, TI = 0.5, 7320 images) and 7.5 mm2 at 118 fps (MIOS  = 1.1, TI = 0.4, 14,160 images). The PCH was not significantly different for 34 fps (TI = 0.5, MIOS  = 0.8) (10.7 mm2 ), compared to 61 and 118 fps, above, indicating some value for the TI as a predictive indicator of PCH. MIIS thresholds were 0.42, 0.46, and 0.49 for 34, 61 and 118 fps, respectively. CONCLUSIONS: The increase in PCH at low fps was associated with delivering more relatively high amplitude grazing pulse exposures during slower image scans. No significant PCH was found for the MIOS setting of 0.5, corresponding to in MIIS values of 0.35-0.39.


Assuntos
Pneumopatias , Ratos , Animais , Ratos Sprague-Dawley , Modelos Animais de Doenças , Pneumopatias/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Pulmão/irrigação sanguínea , Hemorragia/diagnóstico por imagem
10.
Int J Bioprint ; 8(4): 613, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36404785

RESUMO

Three-dimensional (3D) printing technology provides advanced technical support for designing personalized bone tissue engineering scaffold. In this study, two porous diffusing models, namely, average and layered perforated cylindrical scaffolds, were designed for bone tissue engineering scaffold. The designed models were fabricated by liquid crystal display mask stereolithography printing. Structural design and finite element mechanical analysis were conducted. 45S5 bioglass was selected as the raw material for preparing the printing inks for bone tissue engineering scaffolds. By adjusting the viscosity and temperature of the slurry, the maximum proportion of 45S5 bioglass (40 wt%) was added into the photosensitive resin for preparing 3D printing slurry. Our results indicated that an optimized sintering condition includes the debinding rate (0.5°C/min), and temperature raising rate (5°C/min) and sintering temperature (1100°C) were proposed to sinter 45S5 bioceramic scaffolds. The amorphous 45S5 bioglass showed good crystallization after sintering, and the scaffold porous structure showed good integrity. Micropores were observed in the struts which interconnected with each other. Moreover, the porosities were tested as 57% and 45% with a uniform pore distribution. The shrinkage rate was about 10% during sintering process due to binder burning and crystallization shrinkage. The compressive strength of the sintered scaffold was 0.71 ± 0.048 MPa and 2.13 ± 0.054 MPa, respectively, which are consistent with the finite element mechanical analysis simulation results. In conclusion, the layered perforated 45S5 bioglass scaffold shows good mechanical properties and porosity, indicating that it could be a promising candidate for bone tissue engineering.

11.
Ultrasound Med Biol ; 48(11): 2276-2291, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36030131

RESUMO

This study investigated induction of pulmonary capillary hemorrhage (PCH) in neonatal pigs (piglets) using three different machines: a GE Venue R1 point-of-care system with C1-5 and L4-12t probes, a GE Vivid 7 Dimension with a 7L probe and a SuperSonic Imagine machine with an SL15-4 probe and shear wave elastography (SWE). Female piglets were anesthetized, and each was mounted vertically in a warm bath for scanning at two or three intercostal spaces. After aiming at an innocuous output, the power was raised for a test exposure. Hydrophone measurements were used to calculate in situ values of mechanical index (MIIS). Inflated lungs were removed and scored for PCH area. For the C1-5 probe at 50% and 100% acoustical output (AO), a PCH threshold of 0.53 MIIS was obtained by linear regression (r2 = 0.42). The L4-12t probe did not induce PCH, but the 7L probe induced zones of PCH in the scan planes. The Venue R1 automated B-line tool applied with the C1-5 probe did not detect PCH induced by the C1-5 probe as B-line counts. However, when PCH induced by C1-5 and 7L exposures were subsequently scanned with the L4-12t probe using the automated tool, B-lines were counted in association with the PCH. The SWE induced PCH at push-pulse positions for 3, 30 and 300 s of SWE with PCH accumulating at 0.33 mm2/s and an exponential rise to a maximum of 18.4 mm2 (r2 = 0.61). This study demonstrated the induction of PCH by LUS of piglets, and supports the safety recommendation for use of MIs <0.4 in neonatal LUS.


Assuntos
Técnicas de Imagem por Elasticidade , Pneumopatias , Animais , Modelos Animais de Doenças , Feminino , Hemorragia/diagnóstico por imagem , Pulmão/irrigação sanguínea , Pulmão/diagnóstico por imagem , Ratos , Ratos Sprague-Dawley , Suínos
12.
Front Bioeng Biotechnol ; 10: 921107, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35814015

RESUMO

Objective: The study aimed to explore a new approach for the treatment of osteosarcoma through combining biomaterials with next-generation small molecule-based targeted therapy. Methods: The model of osteosarcoma was established by 4-hydroxyaminoquinoline 1-oxide (4-HAQO) in mice while the collagen-thermosensitive hydrogel-calcium phosphate (CTC) biocomposites were prepared, and the small molecule inhibitors were virtually screened and synthesized. Then, for the osteosarcoma cell line, MG-63 cells were used to validate our bioinformatic findings in vitro, and the mouse osteosarcoma models were treated by combing CTC composites and small-molecule inhibitors after debridement. Results: Five compounds, namely, ZINC150338698, ZINC14768621, ZINC4217203, ZINC169291448, and ZINC85537017, were found in the ZINK database. Finally, ZINC150338698 was selected for chemical synthesis and experimental verification. The results of the MTT assay and Hoechst staining showed that the small-molecule inhibitor ZINC150338698 could significantly induce MG-63 cell death. Furthermore, CTC composites and ZINC150338698 could repair the bone defects well after the debridement of osteosarcoma. In addition, the biomaterials and small-molecule inhibitors have good biocompatibility and biosafety. Conclusion: Our findings not only offer systems biology approach-based drug target identification but also provide new clues for developing novel treatment methods for future osteosarcoma research.

13.
Org Lett ; 24(27): 4865-4870, 2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35775729

RESUMO

Herein, we report the Pd(0)-catalyzed intermolecular asymmetric dearomative [3 + 2] annulation of phenols with vinyl cyclopropanes via in situ generated ortho-quinone methide intermediates. A series of highly functionalized spiro-[5,6] bicycles which bear three contiguous stereogenic centers including one all-carbon quaternary were obtained with excellent stereoselectivities. Density functional theory (DFT) calculations indicate that the reactions were controlled by thermodynamics.


Assuntos
Ciclopropanos , Paládio , Catálise , Estrutura Molecular , Fenóis , Estereoisomerismo
14.
Biomed Mater Eng ; 33(5): 365-375, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35180103

RESUMO

BACKGROUD: Calcium phosphate biomaterials have excellent bone inductivity, and exercise can promote the bone formation of biomaterials in animals, but it is not clear which exercise mode is better. OBJECTIVE: To explore the effect of different exercise modes on osteoinduction by calcium phosphate-based biomaterials which were implanted in mice. METHOD: The collagen-thermosensitive hydrogel-calcium phosphate (CTC) composite was prepared and transplanted in the thigh muscle of mice, then all mice were divided randomly into four groups (n = 10): the uphill running group, the downhill running group, the swimming group and the control group (conventional breeding). Ten weeks later, the samples were harvested, fixed, decalcified, embedded in paraffin and stained with hematoxylin and eosin (H&E), and then the osteoinduction phenomenon was observed and compared through digital slice scanning system. The area percentage of new bone-related tissues and the number of osteocytes and chondrocytes were counted and calculated. Lastly, the immunohistochemistry of type I collagen (ColI) and osteopontin (OPN) was performed to identify the new bone tissues. RESULTS: The area percentage of new bone-related tissues and the number of osteocytes and chondrocytes were positively correlated; ordering from most to least of each group were as followings: the uphill running group > the swimming group > the downhill running group > the control group. The immunostaining of ColI and OPN results showed that both of the two proteins were identified in the new bone tissues, indicating that the CTC composite could induce ectopic bone formation in mice, especially training for uphill running and swimming. CONCLUSION: Our results show that uphill running or swimming is a form of exercise that is beneficial to osteogenesis. According to this, we propose treatment with artificial bone transplantation to patients who suffer from bone defects. Patients should do moderate exercise, such as running uphill on the treadmill or swimming.


Assuntos
Corrida , Animais , Materiais Biocompatíveis/metabolismo , Osso e Ossos , Fosfatos de Cálcio/metabolismo , Camundongos , Músculo Esquelético/fisiologia , Corrida/fisiologia
15.
Ultrasound Med Biol ; 47(8): 2331-2338, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33972153

RESUMO

Induction of pulmonary capillary hemorrhage (PCH) by lung ultrasound (LUS) depends not only on physical exposure parameters but also on physiologic conditions and drug treatment. We studied the influence of xylazine and clonidine on LUS-induced PCH in spontaneously hypertensive and normotensive rats using diagnostic B-mode ultrasound at 7.3 MHz. Using ketamine anesthesia, rats receiving saline, xylazine, or clonidine treatment were tested with different pulse peak rarefactional pressure amplitudes in 5 min exposures. Results with xylazine or clonidine in spontaneously hypertensive rats were not significantly different at the three exposure pulse peak rarefactional pressure amplitudes, and thresholds were lower (2.2 MPa) than with saline (2.6 MPa). Variations in LUS PCH were not correlated with mean systemic blood pressure. Similar to previous findings for dexmedetomidine, the clinical drug clonidine tended to increase susceptibility to LUS PCH.


Assuntos
Anti-Hipertensivos/uso terapêutico , Capilares , Clonidina/uso terapêutico , Hemorragia/tratamento farmacológico , Hemorragia/etiologia , Hipertensão/complicações , Hipertensão/tratamento farmacológico , Pulmão/irrigação sanguínea , Xilazina/uso terapêutico , Animais , Hemorragia/diagnóstico por imagem , Masculino , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Ondas Ultrassônicas , Ultrassonografia
16.
J Ultrasound Med ; 40(4): 787-794, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32856724

RESUMO

OBJECTIVES: Lung ultrasound (LUS) exposure can induce pulmonary capillary hemorrhage (PCH), depending on biological and physical exposure parameters. This study was designed to investigate the variation in the LUS induction of PCH due to hemorrhagic shock, which itself can engender pulmonary injury. METHODS: Male rats were anesthetized with isoflurane in air. Shock was induced by withdrawal of 40% of the blood volume and assessed by the blood pressure detected by a femoral artery catheter and by blood glucose tests. B-mode ultrasound was delivered at 7.3 MHz with a low output (-20 dB) for aiming and with the maximal output (0 dB) for exposure. Pulmonary capillary hemorrhage was quantified by an assessment of comet tail artifacts in the LUS images and by measurement of PCH areas on the surface of fresh lung samples. RESULTS: Tests without shock or catheterization surgery gave results for PCH similar to those of previous studies using different methods. Exposure before hemorrhagic shock gave a mean PCH area ± SE of 24.8 ± 9.2 mm2 on the ultrasound scan plane, whereas exposure after shock gave 0 PCH (P < .001; n = 7). CONCLUSIONS: The presence of hemorrhagic shock significantly reduces the occurrence of LUS-induced PCH.


Assuntos
Choque Hemorrágico , Animais , Modelos Animais de Doenças , Hemorragia/diagnóstico por imagem , Hemorragia/etiologia , Pulmão/diagnóstico por imagem , Masculino , Ratos , Ratos Sprague-Dawley , Choque Hemorrágico/diagnóstico por imagem
17.
Ultrasound Med Biol ; 46(8): 1978-1985, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32423571

RESUMO

Pulmonary capillary hemorrhage induction by diagnostic ultrasound (DUS-PCH) was investigated with respect to the influence of the fraction of inspired oxygen (FiO2). Sprague-Dawley rats were anesthetized with Telazol only (TO) or Telazol plus xylazine (TX), which can enhance DUS-PCH. A linear array probe (10 L, GE Vivid 7 Dimension) was used in B-mode at 7.5 MHz to expose the right lung. FiO2 at 10%, 20%, 60% and 100% was delivered through a nose cone. On the ultrasound images, the PCH effect was observed as growing comet tail (B-line) artifacts and as subpleural consolidated segments at higher FiO2. PCH for TO with 20% and 60% FiO2 were significantly greater (p < 0.05) than for the 10% FiO2. PCHs with TX at 10% and 20% FiO2 were significantly greater (p < 0.02) than those for TO anesthesia. Added xylazine and high percentages of FiO2 reduced PCH thresholds, but xylazine and high percentages of FiO2 together did not lower the PCH threshold further. The lowest threshold observed, 1.4 MPa, corresponded to an in situ mechanical index of 0.5.


Assuntos
Capilares/efeitos da radiação , Hemorragia/etiologia , Pneumopatias/etiologia , Oxigênio/metabolismo , Ultrassonografia/efeitos adversos , Animais , Feminino , Ratos , Ratos Sprague-Dawley
18.
Biomed Pharmacother ; 118: 109382, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31545257

RESUMO

Renal cell carcinoma (RCC) is one of the most lethal urological malignancies, yet its pathogenesis remains unclear. Here, we reported a long non-coding RNA (lncRNA), NONHSAT 113026 (NOAT113026), which may play an important role in the pathogenesis of RCC. The expression level of NOAT113026 was estimated by qPCR from 76 pairs of RCC and non-tumor (NT) samples. The correlation between NOAT113026 and clinical data of RCC patients was analyzed. NOAT113026 was overexpressed in 786-O and ACHN cell lines by lentivirus-mediated technology and the oncological behavioral changes of RCC cells were observed along with tumorigenicity in experimental nude mice. Compared to the adjacent tissues, NOAT113026 was noticeably downregulated in RCC. Survival analysis showed that the lower the expression level of NOAT113026 was, the shorter the disease-free survival and overall survival in RCC would be. Overexpression of NOAT113026 can decrease the ability of cell migration, invasion, proliferation, and colony formation by regulating NF-κB/p50 and SLUG through a mechanism that involves lncRNA-mRNA interactions. In conclusion, our data suggest that NOAT113026 could be a carcinostatic RNA in RCC, which may serve as a potential prognostic factor and a promising therapeutic target for malignant RCC.


Assuntos
Carcinogênese/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Neoplasias Renais/genética , Neoplasias Renais/patologia , Subunidade p50 de NF-kappa B/metabolismo , RNA Longo não Codificante/metabolismo , Fatores de Transcrição da Família Snail/metabolismo , Regiões 3' não Traduzidas/genética , Animais , Sequência de Bases , Biomarcadores Tumorais/metabolismo , Carcinogênese/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Inflamação/patologia , Masculino , Camundongos Nus , Invasividade Neoplásica , Prognóstico , RNA Longo não Codificante/genética , Regulação para Cima/genética
19.
Artif Cells Nanomed Biotechnol ; 47(1): 3711-3719, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31522559

RESUMO

Cervical cancer (CC) is a primary gynecological malignancy worldwide. Cancer stem cells (CSCs) possess enhanced tumor-initiating and self-renewing abilities. MicroRNAs (miRNAs) play essential roles in CSCs' tumorigenesis. This study investigated the effects of miR-146a on CSCs' tumorigenesis and invasion. Tumorsphere cells (TCs) were enriched from the HeLa cell line. Real-time PCR, Western blots, ALDH assays, colony formation and invasion assays, luciferase reporter assays and the Xenograft mouse model were used to determine the underlying mechanism of CC. The results showed that TCs displayed higher ALDH activity and miR-146a was upregulated in differentiated TCs. Moreover, miR-146a inhibitor increased colony formation and cell invasion in TCs while miR-146a mimics displayed the opposite roles. An inverse relationship between miR-146a and VEGF expression was found in TCs and the luciferase reporter assay revealed that VEGF was a direct target of miR-146a. Inhibition of VEGF reversed the effects of miR-146a inhibitor on TCs. The activated CDC42/PAK1 signaling was associated with TCs' tumorigenesis and invasion. Furthermore, miR-146a inhibitor-treated TCs promoted tumor growth in nude mice. Altogether, the results suggest that miR-146a modulated TCs' tumor formation and invasion and was associated with VEGF/CDC42/PAK1 signaling. This study provided insight into developing new therapeutic strategies for CC.


Assuntos
Carcinogênese/genética , MicroRNAs/genética , Células-Tronco Neoplásicas/patologia , Neoplasias do Colo do Útero/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteína cdc42 de Ligação ao GTP/metabolismo , Quinases Ativadas por p21/metabolismo , Animais , Sequência de Bases , Proliferação de Células/genética , Transformação Celular Neoplásica , Feminino , Células HeLa , Humanos , Camundongos , Invasividade Neoplásica/genética , Transdução de Sinais/genética
20.
Ultrasound Med Biol ; 45(11): 2993-3004, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31412979

RESUMO

The occurrence of the pulmonary capillary hemorrhage (PCH) bioeffect of diagnostic ultrasound in rats was investigated for a SuperSonic Imagine shear wave elastography system (Aixplorer, Supersonic Imagine, Aix-en-Provence, France). The elastography imaging repeated at 1 Hz and consisted of widely spaced B-mode image pulses, supersonic push (SSP) pulses and shear wave imaging (SWI) pulses. Groups of rats anesthetized with ketamine and xylazine, or with ketamine only, were imaged on their right side in a warm water bath for one frame, 30 s and 300 s. The image focus and region of interest were adjusted to give exposure only with the background B-mode imaging, or primarily with the SSP and SWI pulses. A sham group had only low power aiming scans. The lungs were removed 5 min after exposure and evaluated for PCH area and volume. The B mode was notably ineffective and produced significant PCH only at the maximum 0 dB output. The SSP pulses together with the SWI pulses produced significant PCH for 300 s, 30 s and even single image exposures. Peak rarefactional pressure amplitude PCH thresholds for 300 s exposure were the same with or without the B-mode pulses at 1.5 MPa (in situ mechanical index, MIIS = 0.67). A 30 s duration resulted in a slightly increased threshold of 1.7 MPa (MIIS = 0.76). The omission of xylazine from the anesthetic, which reduces the sensitivity of rat lung to PCH occurrence, resulted in an increased threshold of 2.1 MPa (MIIS = 0.94). The unique SSP pulses were much more effective than the B mode, but thresholds were comparable to previous results with other diagnostic ultrasound modes on other systems.


Assuntos
Técnicas de Imagem por Elasticidade/efeitos adversos , Hemorragia/etiologia , Pneumopatias/etiologia , Animais , Capilares , Feminino , Pulmão/irrigação sanguínea , Pulmão/diagnóstico por imagem , Ratos , Ratos Sprague-Dawley
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