This paper presents the design, fabrication and characterization of a miniature PZT-on-CMOS matrix transducer for real-time pediatric 3-dimensional (3D) transesophageal echocardiography (TEE). This 3D TEE probe consists of a 32?×?32 array of PZT elements integrated on top of an Application Specific Integrated Circuit (ASIC). We propose a partitioned transmit/receive array architecture wherein the 8?×?8 transmitter elements, located at the centre of the array, are directly wired out and the remaining receive elements are grouped into 96 sub-arrays of 3?×?3 elements. The echoes received by these sub-groups are locally processed by micro-beamformer circuits in the ASIC that allow pre-steering up to ±37°. The PZT-on-CMOS matrix transducer has been characterized acoustically and has a centre frequency of 5.8 MHz, -6 dB bandwidth of 67%, a transmit efficiency of 6 kPa/V at 30 mm, and a receive dynamic range of 85 dB with minimum and maximum detectable pressures of 5 Pa and 84 kPa respectively. The properties are very suitable for a miniature pediatric real-time 3D TEE probe. 相似文献
Adenosine is a regulatory molecule with widespread physiological effects in almost every cells and acts as a potent regulator of cell growth. Adenosine has been shown to inhibit cell growth and induce apoptosis in the several cancer cells via caspase activation and Bcl-2/Bax pathway. The present study was designed to understand the mechanism underlying adenosine-induced apoptosis in the OVCAR-3 human ovarian cancer cells. MTT viability, BrdU and cell counting assays were used to study the cell proliferation effect of adenosine in presence of adenosine deaminase inhibitor and the nucleoside transporter inhibitor. Cell cycle analysis, propidium iodide and annexin V staining, caspase-3 activity assay, cyclinD1, Cdk4, Bcl-2 and Bax protein expressions were assessed to detect apoptosis. Adenosine significantly inhibited cell proliferation in a concentration-dependent manner in OVCAR-3 cell line. Adenosine induced cell cycle arrest in G0/G1 phase via Cdk4/cyclinD1-mediated pathway. Adenosine induced apoptosis, which was determined by Annexin V-FITC staining and increased sub-G1 population. Moreover, down-regulation of Bcl-2 protein expression, up-regulation of Bax protein expression and activation of caspase-3 were observed in response to adenosine treatment. The results of this study suggest that extracellular adenosine induced G1 cell cycle arrest and apoptosis in ovarian cancer cells via cyclinD1/ Cdk4 and Bcl-2/Bax pathways and caspase-3 activation. These data might suggest that adenosine could be used as an agent for the treatment of ovarian cancer. 相似文献
Glycodelin, previously known as PP14, has been localized in endometrial, ovarian and cervical carcinoma cells. Recently, glycodelin was demonstrated to be expressed in cancerous human breast tissue. In this study, paraffin-embedded slides of carcinoma in situ, invasive carcinomas without metastases, invasive carcinomas with corresponding lymph node metastases, invasive carcinomas with corresponding recurrence and invasive carcinomas with corresponding distant metastases were investigated for glycodelin protein and mRNA expression. Protein expression was found in all cases of carcinoma in situ, in invasive carcinoma without lymph node metastases in 90% of cases, in breast cancer with lymph node metastases in 50% of cases, in breast cancer with recurrence in 38% of cases and in breast cancer with distant metastases in 40% of cases. Results were confirmed by in situ hybridization showing reduced glycodelin expression as lymph node metastasis progressed, compared to carcinoma in situ. Glycodelin mRNA expression is not further reduced in carcinomas with distant metastasis and recurrence compared to carcinoma in situ. Results demonstrate that invasive breast carcinomas without metastases are more likely to express glycodelin. In contrast, cases of breast cancer with metastatic infiltration and recurrence show weak expression of glycodelin. On the basis of these results, we speculate that glycodelin could be used as a prognostic marker for breast cancer. 相似文献
Nitric oxide is an important cytotoxic agent for host defense which also regulates gene expression, signal transduction, and vasodilation. In normal wounds, nitric oxide synthesis and metabolism are significantly increased during inflammation and tissue remodeling. However, nitric oxide production is suppressed in wounds where healing is impaired by diabetes or steroid-treatment. Topical delivery of nitric oxide in therapeutic amounts may alleviate this deficiency and thereby enhance wound repair. Consequently, we developed polyethyleneimine cellulose NONOate polymer, a nonsoluble, nontoxic, polymer-based NONOate--one of a new class of compounds that spontaneously release nitric oxide in a controlled fashion in aqueous media. Polyethyleneimine cellulose NONOate polymer was synthesized from polyethyleneimine cellulose to provide extended nitric oxide release with a half-life of 16 hours. Polyethyleneimine cellulose NONOate polymer or a control polymer was applied topically on full-thickness dermal wounds of rats at the time of wounding and days 3, 7, 10, 14, 17, and 21. Nitric oxide delivery was determined indirectly by measuring urinary nitrate. The first two polyethyleneimine cellulose NONOate polymer applications increased urinary nitrate output twofold to fourfold, whereas urinary nitrate output of control rats did not significantly increase. Nitrate output in polyethyleneimine cellulose NONOate polymer-treated rats was elevated compared with controls after each application, although this was attenuated in later applications. Rate of wound closure was measured with computer-based video imaging. Polyethyleneimine cellulose NONOate polymer-treated wounds were significantly smaller (p < 0.05) on days 7, 10, and 17 relative to controls, based on percentage of wound open relative to initial wound area. In a second experiment, telemetry-implanted rats were wounded to detect potential hypotensive effects as a result of polyethyleneimine cellulose NONOate polymer application. Topical polyethyleneimine cellulose NONOate polymer application to wounds showed no prolonged hypotensive effects, in contrast to a soluble NONOate which suppressed systolic blood pressure for over 6 hours. These results show that a nonsoluble, polymeric NONOate can provide topical nitric oxide delivery to wounds in a controlled manner, which may enhance wound healing. Further studies are in progress with other promising NONOate candidates to establish dose-response effects and therapeutic limits of exogenous nitric oxide release in impaired wound models. 相似文献
Although the key contributors of altering neurological function in hepatic encephalopathy are relatively well known, the electrophysiological mechanism of CA1 damage, a key vulnerable area during hyperammonemia, have not yet been defined. Therefore, here we focus on the electrophysiological mechanisms of cognitive impairments following bile duct ligation (BDL). We performed patch-clamp recordings from the CA1 pyramidal neurons in hippocampus of male Wistar rats, which underwent sham or BDL surgery. A striking electrophysiological change of hippocampal neurons in experimental model of BDL was observed in the present study. Spontaneous firing frequency and rate of action potential (AP) rebound was decreased and afterhyperpolarization amplitude (AHP) was increased significantly in hippocampal cells of BDL animals compared to sham group. Together, the results suggest that altered intrinsic properties of the hippocampal neurons may contribute to the cognitive abnormalities during hepatic encephalopathy (HE), highlighting the electrophysiological mechanisms for providing new treatments against HE.
The role of human papilloma virus (HPV) in the pathogenesis of anogenital dysplasia is now conclusive. However, HPV detection
in formalin-fixed and paraffin-embedded tissues remains controversial. Therefore, the aim of this study was to evaluate morphological
changes directly in tissue specimens using a HPV-DNA detection system involving HPV in situ hybridisation. 相似文献
Aneurysmal lesions are commonly seen in Ehlers-Danlos Syndrome (EDS). To better identify the regional and vessel-specific spectrum of aneurysms in different subtypes of EDS, we performed a systematic review. We searched Medline for relevant studies from 1963 to April 2022. Studies providing a report of any EDS subtype by genetic diagnosis, histologic analysis, or clinical criteria were included. A total of 448 patients from 220 studies were included. 720 vessel-specific aneurysms were reported: 386 in the abdominopelvic area, 165 in the intracranial region, 98 in the thorax, 2 in the extremities, and 6 in the venous system. In 27 out of the 65 patients with ruptured aneurysms, the ruptured aneurysm was the initial presentation. Multiple aneurysms were present in 163 out of 249 patients who had been systematically evaluated for other locations of aneurysms. The head and neck and abdominopelvic regions are two potential foci for aneurysm formation in patients with EDS. The aneurysm development in EDS is not confined to arteries; the venous system and cardiac septa may also be affected. Many patients develop multiple aneurysms, either at the time of the initial presentation or throughout their lifetime and aneurysm formation or rupture may be the first presentation of EDS. 相似文献
Endometriosis is an inflammatory disease; the hallmark of inflammation is over-activation of matrix metalloproteinases (MMPs). The regulatory effects of Resveratrol on MMPs were formerly depicted in other cell lines. This study aimed at investigating the effects of Resveratrol on expression of MMP-2 and -9 in endometriosis patients. This trial was carried out on endometriosis patients (n?=?34) who were randomly divided into treatment (i?=?17) and control (n?=?17) groups. Alongside the routine protocol, the control and treatment groups took placebo and Resveratrol (400?mg), respectively, for 12–14?weeks. Endometrial tissue and fluid as well as blood sampling from both groups were done before and after the intervention. The level of mRNA and protein of both MMP-2 and -9 reduced in the endometrium of treatment group following intervention. Also, the serum and the endometrial fluid concentration of them lowered within the treatment group. Moreover, the serum and endometrial fluid levels of MMP-2 as well as MMP-9 were also diminished following the surgical removal of endometritic lesions. We showed that Resveratrol can modify the inflammation process in the endometrium of women with endometriosis at least in the level of MMP-2 and -9 expressions. The therapeutic potency of Resveratrol in endometriosis needs more clinical studies. 相似文献
Inhibins, dimeric peptide hormones composed of an alpha-subunit and one of two possible beta-subunits (betaA or betaB), exhibit
substantial roles in human reproduction and in endocrine-responsive tumors. However, it is still unclear if normal and cancerous
cervical glandular epithelial cells as well as cervical cancer cell lines of glandular origin express the inhibin-betaA and
-betaB subunits. 相似文献
Caerin 4 is a family of AMPs isolated from the frog called Litoria caerulea. In silico drug designing methods and using machine learning algorithms for AMPs design can reduce their usage restrictions such as production costs and the time required for investigation of their activity and toxicity. In this study, two short peptides were designed based on direct and reverse mirror repeats of GLWQKI conserved sequence from Caerin 4 family that called dCar12 and rCar12. Also, Caerin 4.1 was synthesized without primary GLWQKI sequence and named Car7‐23. Following the synthesis of peptides, their antimicrobial properties, cytotoxicity, secondary structure, and mode of action were further evaluated. Results indicated that rCar12 had a good antibacterial activity (at an MIC of 3.9–62.5 µg/ml), while Car7‐23 did not have any antimicrobial properties. Cytotoxicity of rCar12 at MICs range was <5%, which is much less than Caerin 4.1. In conclusion, rCar12 with reverse mirror repeat has different functional properties compared with dCar12. These results corroborate the fact that in two peptides with identical residues and length, the position and arrangement of amino acids are very important concerning peptide function. Moreover, GLWQKI sequence is highly crucial for the antimicrobial activity of Caerin 4 antimicrobial peptide family. 相似文献