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1.
Mol Biol Rep ; 48(11): 7379-7385, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34626314

RESUMO

BACKGROUND: Cryptochrome 1 (cry1), the core regulator of the circadian clock, is essential for ontogeny and mammalian reproduction. Unlike in other tissues, the cry1 gene have noncircadian functions in spermatogenesis, which implies the unique role of cry1 gene in the development of testis. The role of cry1 during the puberty has not been described yet. This study aimed to explore the relationship between cry1 expression and spermatogenic cell numbers. METHODS AND RESULTS: We analyzed testicular tissues from Hu sheep aged 0-180 days by hematoxylin and eosin staining, measured cry1 and cell proliferation regulatory factors (bricd5, tnfrsf21, cdk1) expression by quantitative real-time PCR and characterized the transcription factor in the 5' flanking region of cry1 gene. The data revealed that the number of spermatocytes and early spermatocytes increased rapidly from 90 to 120 dpp (day postpartum). Correspondingly, there was a marked variation in the cry1 and cell proliferation related genes (bricd5, tnfrsf21, cdk1) mRNA expression in the testes from the age of 90 days to 180 days (p < 0.05). We also identified some transcription factors (tcfl5) related to cell proliferation. CONCLUSIONS: There is a significant causal relationship between the transcription level of cry1 gene in Hu sheep testes and the number of spermatogenic cells. It is speculated that cry1 gene may regulate the proliferation of spermatogenic cells by regulating the expression of cell proliferation related genes such as bricd5, tnfrsf21 and cdk1.


Assuntos
Proteína Quinase CDC2/genética , Criptocromos/genética , Receptores do Fator de Necrose Tumoral/genética , Maturidade Sexual , Espermatogênese , Testículo/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proliferação de Células , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Ovinos , Espermatócitos/metabolismo , Espermatócitos/fisiologia , Testículo/crescimento & desenvolvimento , Testículo/fisiologia
2.
Angew Chem Int Ed Engl ; 60(39): 21426-21433, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34314080

RESUMO

Although numerous adsorbent materials have been reported for the capture of radioactive iodine, there is still demand for new absorbents that are economically viable and can be prepared by reliable synthetic protocols. Herein, we report a coordination-driven self-assembly strategy towards adsorbents for the sequential confinement of iodine molecules. These adsorbents are versatile heterometallic frameworks constructed from aluminum molecular rings of varying size, flexible copper ions, and conjugated carboxylate ligands. Additionally, these materials can quickly remove iodine from cyclohexane solutions with a high removal rate (98.8 %) and considerable loading capacity (555.06 mg g-1 ). These heterometallic frameworks provided distinct pore sizes and binding sites for iodine molecules, and the sequential confinement of iodine molecules was supported by crystallographic data. This work not only sets up a bridge between molecular rings and infinite porous networks but also reveals molecular details for the underlying host-guest binding interactions at crystallographic resolution.

3.
Angew Chem Int Ed Engl ; 59(38): 16735-16740, 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32524709

RESUMO

Presented herein are the AlIII molecular ring architectures from 8-ring to 16-ring. Although there are numerous reported cyclic coordination compounds based on transition metals, gallium, or lanthanides, the Al versions are less developed due to the fast hydrolysis nature of Al3+ ion. With the assistant of monohydric alcohols, a series of atomic precisely Al molecular rings based on benzoates are synthesized. The ring expansion of these Al-rings from 8-ring to 16-ring is related to the monohydric alcohol structure-directing agents. Moreover, the organic ligands on the Al-rings can be modified by using various benzoate derivatives, which lead to tunable surface properties of the Al-rings from hydrophilicity to ultra-hydrophobicity. Importantly, 4-aminobenzoic acid bridged 16-ring is soluble in organic solvents and exhibits high solution stability revealed by mass spectroscopy. Ligand substitution also can be performed between these Al-rings, which reveal controllable ligand functionalization of these Al-rings.

4.
Environ Sci Pollut Res Int ; 27(18): 23270-23280, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32335836

RESUMO

In this study, the mud-phosphorus slurry was used to simultaneously remove SO2 and NOx. The technology proposed new avenues for the purification and utilization of remove SO2 and NOx in flue gas. The effects of reaction temperature, solid-liquid ratio, and oxygen content on the efficiency of desulfurization and denitrification were studied experimentally. Results show that the parameters were solid-liquid ratio of 5.0 g/40 mL, T = 60 °C, φ (O2) = 20%, Q = 300 mL/min under the best experimental conditions. The maximum amount of ozone generated was 563.8 mg/m3. The reaction time with desulfurization rate ≥ 99% was 340 min; the reaction time with denitrification rate ≥ 99% was 160 min. Response surface analysis method was used to perform a three-factor three-level response surface experiment. Results show that the oxygen content had a highly significant effect on the desulfurization and denitrification efficiency, and the relationship between the desulfurization and denitrification efficiency was oxygen content > mud-phosphorus slurry liquid-solid ratio > reaction temperature. The process is simple, the solid waste is used to treat the flue gas, and the removal effect is good, which is convenient for popularization.


Assuntos
Fósforo , Dióxido de Enxofre , Temperatura
5.
Med Phys ; 2018 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-29963699

RESUMO

PURPOSE: High-intensity focused ultrasound (HIFU) is becoming an effective and noninvasive treatment modality for cancer and solid tumors. In order to avoid the cancer relapse and guarantee the success of ablation, there should be no gaps left among all HIFU-generated lesions. However, there are few imaging approaches available for detecting the HIFU lesion gaps in real time during ablation. METHODS: Transient axial shear strain elastograms (ASSEs) were proposed and evaluated both numerically and experimentally to detect the lesion gaps immediately after the cessation of therapeutic HIFU exposure. Acoustic intensity and subsequent acoustic radiation force were first calculated by solving the nonlinear Khokhlov-Zabolotskaya-Kuznetzov (KZK) equation. Motion of being- and already-treated lesions during and after HIFU exposure was simulated using the transient dynamic analysis module of finite element method (FEM). The corresponding B-mode sonography of tissue-mimicking phantom with two HIFU lesions inside was simulated by FIELD II, and then axial strain elastograms (ASEs) under static compression and transient ASSEs were reconstructed. An ultrasound imaging probe was integrated with the HIFU transducer and used to obtain radio frequency (RF) echo signals at high frame rate using plane wave imaging (PWI). The resulting strains were mapped using the correlation-based method and block search strategy. RESULTS: Acoustic radiation force from the therapeutic HIFU burst is sufficiently strong to produce significant displacement. As a result, large and highly localized axial shear strain appears in the gap zone between two HIFU-generated lesions and then disappears after sufficient HIFU ablation (no gap between them). Such capability of detecting the lesion gap is validated at the varied acoustic radiation force density, gap width, and the size of the lesion. In contrast, conventional ASEs using the static compression cannot distinguish whether a gap exists between lesions. Static ASEs and transient ASSEs reconstructed using both high-speed photography and sonography in the gel phantom show the same conclusion as that in the simulation. Ex vivo tissue experiments further confirmed that the presence of large axial shear strain in the gap zone. The ratios of axial shear strain in the porcine kidney and liver samples had statistical differences for two HIFU-generated lesions without and with a gap (P < 0.05). CONCLUSIONS: Large axial shear strain induced by the acoustic radiation force from therapeutic HIFU burst only appears between two HIFU-generated lesions with a gap between them. Transient ASSEs reconstructed immediately after the cession of HIFU exposure can easily, reliably, and sensitively detect the gap between produced lesions, which would provide real-time feedback to enhance the success of HIFU ablation.

6.
PLoS One ; 12(11): e0188206, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29161293

RESUMO

High-intensity focused ultrasound (HIFU) has been emerging as an effective and noninvasive modality in cancer treatment with very promising clinical results. However, a small vessel in the focal region could be ruptured, which is an important concern for the safety of HIFU ablation. In this study, lesion formation in the polyacrylamide gel phantom embedded with different tubing (inner diameters of 0.76 mm and 3 mm) at varied flow speeds (17-339 cm/s) by HIFU ablation was photographically recorded. Produced lesions have decreased length (~30%) but slightly increased width (~6%) in comparison to that without the embedded tubing. Meanwhile, bubble activities during the exposures were measured by passive cavitation detection (PCD) at the varied pulse repetition frequency (PRF, 10-30 Hz) and duty cycle (DC, 10%-20%) of the HIFU bursts. High DC and low flow speed were found to produce stronger bubble cavitation whereas no significant influence of the PRF. In addition, high-speed photography illustrated that the rupture of tubing was produced consistently after the first HIFU burst within 20 ms and then multiple bubbles would penetrate into the intraluminal space of tubing through the rupture site by the acoustic radiation force. Alignment of HIFU focus to the anterior surface, middle, and posterior surface of tubing led to different characteristics of vessel rupture and bubble introduction. In summary, HIFU-induced vessel rupture is possible as shown in this phantom study; produced lesion sizes and shapes are dependent on the focus alignment to the tubing, flow speed, and tubing properties; and bubble cavitation and the formation liquid jet may be one of the major mechanisms of tubing rupture as shown in the high-speed photography.


Assuntos
Vasos Sanguíneos/efeitos da radiação , Ablação por Ultrassom Focalizado de Alta Intensidade/efeitos adversos , Ablação por Ultrassom Focalizado de Alta Intensidade/instrumentação , Neoplasias/terapia , Acústica , Resinas Acrílicas/química , Vasos Sanguíneos/fisiopatologia , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Humanos , Neoplasias/fisiopatologia , Imagens de Fantasmas , Fotografação
7.
IEEE Trans Biomed Eng ; 63(8): 1642-52, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26126268

RESUMO

Platelet-rich plasma (PRP) is a volume of autologous plasma that has a higher platelet concentration above baseline. It has already been approved as a new therapeutic modality and investigated in clinics, such as bone repair and regeneration, and oral surgery, with low cost-effectiveness ratio. At present, PRP is mostly prepared using a centrifuge. However, this method has several shortcomings, such as long preparation time (30 min), complexity in operation, and contamination of red blood cells (RBCs). In this paper, a new PRP preparation approach was proposed and tested. Ultrasound waves (4.5 MHz) generated from piezoelectric ceramics can establish standing waves inside a syringe filled with the whole blood. Subsequently, RBCs would accumulate at the locations of pressure nodes in response to acoustic radiation force, and the formed clusters would have a high speed of sedimentation. It is found that the PRP prepared by the proposed device can achieve higher platelet concentration and less RBCs contamination than a commercial centrifugal device, but similar growth factor (i.e., PDGF-ßß). In addition, the sedimentation process under centrifugation and sonication was simulated using the Mason-Weaver equation and compared with each other to illustrate the differences between these two technologies and to optimize the design in the future. Altogether, ultrasound method is an effective method of PRP preparation with comparable outcomes as the commercially available centrifugal products.


Assuntos
Remoção de Componentes Sanguíneos/métodos , Plasma Rico em Plaquetas , Ultrassom/métodos , Plaquetas/citologia , Centrifugação , Eritrócitos/citologia , Humanos , Microesferas , Tamanho da Partícula , Plasma Rico em Plaquetas/citologia , Plasma Rico em Plaquetas/fisiologia
8.
Oncol Lett ; 5(6): 1943-1947, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23833672

RESUMO

Despite a large number of studies indicating that celecoxib plays an important role in the prevention and treatment of tumors, the detailed molecular mechanisms are not well understood. The aim of the present study was to investigate the effect of celecoxib on insulin-like growth factor 1 (IGF-1)-induced growth and invasion in non-small cell lung cancer (NSCLC). For these experiments, IGF-1-induced cell growth and invasion were analyzed in A549 cells in the presence and absence of celecoxib. The effects of celecoxib on the expression of phosphorylated type-1 IGF receptor (IGF-1R) and phosphorylated AKT (p-AKT) were examined using western blot analysis. The influence of celecoxib on IGF-binding protein-3 (IGFBP-3) expression was analyzed using ELISA. Celecoxib inhibited IGF-1-stimulated growth and invasion in a dose-dependent manner. Celecoxib also reduced the expression of IGF-1R, IGFBP-3 and phosphorylation of AKT. The results suggest that modulating the IGF axis may be a new mechanism for the anticancer effect of celecoxib on NSCLC.

9.
J Transl Med ; 11: 141, 2013 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-23759023

RESUMO

BACKGROUND: The α2-adrenoreceptor agonist dexmedetomidine is known to provide renoprotection against ischemia and reperfusion (I/R) injury. However the underlying molecular mechanisms remain unclear. The purpose of this study was to investigate whether the Janus kinase and signal transducer and activator of transcription (JAK/STAT) signaling pathway plays a role in dexmedetomidine's renoprotection. METHODS: I/R model was induced by bilateral renal pedicle clamping for 45 min followed by 48 h of reperfusion in male Wistar rat. Sham laparotomy served as controls. Animals received dexmedetomidine (50 µg/kg, i.p.) in the absence or presence of atipamezole (250 µg/kg, i.p.), or vehicle (DMSO) in the absence or presence of selective JAK2 inhibitor tyrphostin AG490 (10 mg/kg, i.p.) before ischemia. Renal function, histology, apoptosis, expression of cleaved caspase 3 protein, intercellular adhesion molecule-1 (ICAM-1), monocyte chemoattractant protein-1 (MCP-1) and phosphorylations of JAK2, STAT1 and STAT3 were assessed. RESULTS: The animals treated with either dexmedetomidine or AG490 exhibited an improved renal functional recovery, attenuated histological lesions and reduced number of apoptotic tubular epithelial cells. Either dexmedetomidine or AG490 inhibited the phosphorylations of JAK2 and its downstream molecule STAT1 and STAT3, accompanied by down-regulation the expression of cleaved caspase 3, ICAM-1 and MCP-1 proteins, and significantly ameliorated renal I/R injury. CONCLUSIONS: Dexmedetomidine protects kidney against I/R injury, at least in part, through its inhibitory effects on injury-induced activation of JAK/STAT signaling pathway. If our data can be extrapolated to clinical setting, then dexmedetomidine may therefore serve as a clinical strategy to treat/prevent perioperative renal I/R injury.


Assuntos
Dexmedetomidina/uso terapêutico , Janus Quinases/metabolismo , Rim/patologia , Substâncias Protetoras/uso terapêutico , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/prevenção & controle , Fatores de Transcrição STAT/metabolismo , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Quimiocina CCL2/sangue , Dexmedetomidina/farmacologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Molécula 1 de Adesão Intercelular/sangue , Rim/efeitos dos fármacos , Rim/fisiopatologia , Testes de Função Renal , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/patologia , Masculino , Fosforilação/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Ratos Wistar , Traumatismo por Reperfusão/sangue , Traumatismo por Reperfusão/fisiopatologia , Transdução de Sinais/efeitos dos fármacos
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