Pulse transit time (PTT) has attracted much interest for cuffless blood pressure (BP) measurement. However, its limited accuracy is one of the main problems preventing its widespread acceptance. ...Arterial BP oscillates mainly at high frequency (HF) because of respiratory activity, and at low frequency (LF) because of vasomotor tone. Prior studies suggested that PTT can track BP variation in HF range, but was inadequate to follow the LF variation, which is probably the main reason for its unsatisfactory accuracy. This paper presents a new indicator, the photoplethysmogram intensity ratio (PIR), which can be affected by changes in the arterial diameter, and, thus, trace the LF variation of BP. Spectral analysis of BP, PTT, PIR, and respiratory signal confirmed that PTT was related to BP in HF at the respiratory frequency, while PIR was associated with BP in LF range. We, therefore, develop a novel BP estimation algorithm by using both PTT and PIR. The proposed algorithm was validated on 27 healthy subjects with continuous Finapres BP as reference. The results showed that the mean ± standard deviation (SD) for the estimated systolic, diastolic, and mean BP with the proposed method against reference were -0.37 ± 5.21, -0.08 ± 4.06, -0.18 ± 4.13 mmHg, and mean absolute difference (MAD) were 4.09, 3.18, 3.18 mmHg, respectively. Furthermore, the proposed method outperformed the two most cited PTT algorithms for about 2 mmHg in SD and MAD. These results demonstrated that the proposed BP model using PIR and PTT can estimate continuous BP with improved accuracy.
Background/Aims: Periplocin is extracted from the traditional herbal medicine cortex periplocae, which has been reported to suppress the growth of cancer cells. However, little is known about its ...effect on gastric cancer cells. Methods: Gastric cancer cells were treated with periplocin, and cell viability was assessed using MTS assay. Flow cytometry and TUNEL staining were performed to evaluate apoptosis, and protein expression was examined by western blotting. Microarray analysis was used to screen for changes in related genes. Results: We found that periplocin had an inhibitory effect on gastric cancer cell viability in a dose-dependent manner. Periplocin inhibited cell viability via the ERK1/2-EGR1 pathway to induce apoptosis. Periplocin also inhibited the growth of tumor xenografts and induced apoptosis in vivo. Conclusion: Our results show that periplocin inhibits the proliferation of gastric cancer cells and induces apoptosis in vitro and in vivo, indicating its potential to be used as an antitumor drug.
In this work, we present a multi-wavelength (MW) PPG method exploiting the wavelength dependence of light penetration in skin tissue to provide depth resolution of skin blood pulsation. The MW PPG ...system requires two to three light sources in different wavelengths and extracts the arterial blood pulsation through a multi-wavelength multi-layer light-skin interaction model, which removes the capillary pulsation (determined from the short-wavelength PPG signal) from the long-wavelength PPG signal using absorption weighting factors that are quasi-analytically calibrated. The extracted pulsations are used to calculate blood pressure (BP) through pulse transit time (PTT), and the results are compared with those obtained from the single wavelength PPG method. The comparative study is clinically performed on 20 subjects including 10 patients diagnosed with cardiovascular diseases and 10 healthy subjects. The result demonstrates that the MW PPG method significantly improves the measurement accuracy of systolic BP (SBP), reducing the mean absolute difference between the reference and the estimated SBP values from 5.7 mmHg (for single-wavelength PPG) to 2.9 mmHg (for three-wavelength PPG).
As one of the main diseases leading to end-stage renal disease, steroid-resistant nephrotic syndrome(SRNS) can cause serious complications such as infection. Without effective control, this disease ...can further lead to the malignant development of the renal function, bringing serious social and economic burdens. As previously reported, the formation of SRNS is mostly related to the podocyte injury in the body, i.e., the injury of glomerular visceral epithelial cells. Phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt) signaling pathway, nuclear transcription factor-κB(NF-κB) signaling pathway, mammalian target of rapamycin(mTOR)/adenosine monophosphate(AMP)-activated protein kinase(AMPK), transforming growth factor(TGF)-β1/Smads, and other signaling pathways are classical signaling pathways related to podocyte injury. By regulating the expression of signaling pathways, podocyte injury can be intervened to improve the adhesion between podocyte foot processes and glomerular basement membrane and promote th
Two skeletally novel tetracyclic diterpenoids, psathyrins A (1) and B (2), have been characterized from cultures of the basidiomycete Psathyrella candolleana. Their structures including absolute ...configurations were established by means of spectroscopic methods, as well as ECD calculations. They possess a novel 5/5/4/6-fuesd ring system, for which the biosynthetic pathway is proposed. Compounds 1 and 2 inhibited the growth of Staphylococcus aureus and Salmonella enterica.
Background
Optimal lumbar puncture segment selection remains controversial. This study aims to analyze anatomical differences among L3-4, L4-5, and L5-S1 segments across age groups and provide ...quantitative evidence for optimized selection.
Methods
80 cases of CT images were collected with patients aged 10–80 years old. Threedimensional models containing L3-S1 vertebrae, dural sac, and nerve roots were reconstructed. Computer simulation determined the optimal puncture angles for the L3-4, L4-5, and L5-S1 segments. The effective dural sac area (ALDS), traversing nerve root area (ATNR), and area of the lumbar inter-laminar space (ALILS) were measured. Puncture efficacy ratio (ALDS/ALILS) and nerve injury risk ratio (ATNR/ALILS) were calculated. Cases were divided into four groups: A (10–20 years), B (21–40 years), C (41–60 years), and D (61–80 years). Statistical analysis was performed using SPSS.
Results
1) ALDS was similar among segments; 2) ATNR was greatest at L5-S1; 3) ALILS was greatest at L5-S1; 4) Puncture efficacy ratio was highest at L3-4 and lowest at L5-S1; 5) Nerve injury risk was highest at L5-S1. In group D, L5-S1 ALDS was larger than L3-4 and L4-5. ALDS decreased after age 40. Age variations were minimal across parameters.
Conclusion
The comprehensive analysis demonstrated L3-4 as the optimal first-choice segment for ages 10–60 years, conferring maximal efficacy and safety. L5-S1 can serve as an alternative option for ages 61–80 years when upper interspaces narrow. This study provides quantitative imaging evidence supporting age-specific, optimized lumbar puncture segment selection.
Miracle fruit (Synsepalum dulcificum) is an edible berry, and is known for its ability to turn sour to sweet. The leaf of S. dulcificum has been used as additives in food, medicine and cosmetic ...industries. In this study, two new pairs of enantiomeric coumarinolignans, synsepalumins A and B (1 and 2), three new pentacyclic triterpenoids, 3-O-cis-p-coumaroyl-2α,3β,29-trihydroxy-olean-12-en-28-oic acid (3), 3-O-trans-p-coumaroyl-2α,3β,29-trihydroxy-olean-12-en-28-oic acid (4), and 3-O-cis-p-coumaroyl-3β,19α-hydroxy-urs-12-en-28-oic acid (6), along with twenty-five known compounds (5, 7−30) were isolated from the leaves of S. dulcificum. Compounds 1 and 2 are two rare tricyclic 7-hydroxycoumarins featuring a classic bicyclic 7-hydroxycoumarin fused with a (1,4)-dioxane ring. Their structures were elucidated by the spectroscopic data analyses and quantum chemical electronic circular dichroism calculations. Meanwhile, compound 4 (SMG-1) significantly inhibited proliferation of HepG2 (IC50 = 13.9 ± 0.3 μM) and HCCLM3 (IC50 = 11.8 ± 0.2 μM) cells. We further explored the underlying mechanism of SMG-1 for hepatocellular carcinoma (HCC) cells death, and found that SMG-1 induced reactive oxygen to increase the level of BNIP3 through JNK/p53 pathway and decreased mitochondrial membrane potential, resulting in activating mitophagy. Moreover, SMG-1 up-regulated the Bax and cytoplasm level of Cyt-c to promote Caspase-9/Caspase-3-mediated apoptosis in HCC cells. Therefore, the leaves of S. dulcificum possess the ability to treat HCC.
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•Synsepalum dulcificum has high medicinal and economic values.•Two pairs of undescribed enantiomeric coumarinolignans, three undescribed triterpenoids, along with twenty-five known compounds were isolated from Synsepalum dulcificum leaves.•Some compounds showed significantly antitumor activity against hepatocellular carcinoma cells.•Compound 4 induced reactive oxygen to activate mitophagy and promote Caspase-9/Caspase-3-mediated apoptosis in hepatocellular carcinoma cells.
Graphene aerogels/epoxy composites were prepared by vacuum-impregnated process with graphene aerogels as the functional filler and epoxy resin as polymer matrix. The changes in chemical structure of ...graphene aerogels during the preparation process and carbonization treatment were investigated by FT-IR, XPS and XRD. The results show that GO@PAA aerogel is prepared by the physical interaction between graphene oxide (GO) and polyamide acid (PAA). PAA will be transformed to polyimide by imidization and graphene oxide is partially reduced during the 300 ℃ thermal treatment. With the carbonation temperature increases, reduction degree of graphene sheets and the carbonation degree of polyimide are increased gradually. Meanwhile, SEM images and OM images show that graphene aerogels can also maintain the good three-dimensional network structure after carbonation treatment and vacuum impregnation. On this basis, graphene aerogels, which serve as the functional filler, taking advantage of the good three-dimensional netw
The first-principles calculations with density functional theory were performed to investigate the effects of transition metal elements (Mo, Cu, Fe, Ni and Nb) on the physical properties of the ...Ti–Al-based compounds. Our optimized crystal parameters are in good agreement with the previous theoretical and experimental values. The mechanical stability is verified by the independent elastic constants. The B/G and Poisson’s ratio
ν
both show that Al
6
TiMo is brittle, while other compounds exhibit ductility. The values of compression anisotropy of the compounds are small, but the shear anisotropy of AlCu
2
Ti and AlNi
2
Ti is much more intense than that of other compounds. The anisotropy in elastic properties of AlFe
2
Ti and AlNbTi
2
is smaller than that of the others. It can be seen that the capacity to compress along
c
-axis is smaller than that along
a
-axis and
b
-axis for AlNbTi
2
. For AlNbTi
2
, the anisotropy of the bulk modulus along
a
-axis relative to
b
-axis is more insignificant than that along
c
-axis relative to
b
-axis. The hardness and Debye temperature verify that AlFe
2
Ti has the greatest resistance to the plastic deformation and more intense inter-atomic bonding force, respectively. Band structures and DOS are used to investigate the electronic properties. The band structures without band gaps show that these ternary Ti–Al-based compounds are conductors. DOS shows the interactions between elements and gives the bond properties. Density of states and charge density both show the strong covalent properties of AlFe
2
Ti by the hybridization between Fe-3d and Ti-3d states.
Graphene/carbon fiber/epoxy composites were prepared by autoclave co-curing molding process with graphene prepregs as the functional layer, which were paved on the surface of carbon fiber perform. ...The effect of graphene prepregs on the internal quality, electromagnetic interference shielding performance and mechanical properties of the composites was investigated by ultrasound scanner, metallograph, four-probe instrument, vector network analyzer and electronic universal material testing machine. The results show that the internal quality of the graphene/carbon fiber/epoxy composites will not be influenced by the addition of graphene prepregs, and there are a good interfacial compatibility between graphene functional layer and carbon fiber structural layer. On this basis, graphene prepregs, which serves as the functional layer, taking advantage of excellent electrical conductivity, can improve the electromagnetic interference shielding performance of the corresponding composites rapidly. With only one layer of
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