tsRNA-15797-modified BMSC-derived exosomes mediate LFNG to induce angiogenesis in osteonecrosis of the femoral head

Background

Osteonecrosis of the femoral head (ONFH) is an ischemic disease characterized by the impairment of angiogenesis. We have previously elucidated the role of tsRNAs and BMSC exosomes in ONFH, but whether tsRNA-modified BMSC exosomes promote angiogenesis in ONFH remains unclear.

Methods

The expression of angiogenesis-related tsRNA in plasma exosomes from ONFH patients was examined by q-PCR. The function of tsRNA in HUVECs was identified by CCK-8 and angiogenesis assay. Exosomes purified from tsRNA-15797 overexpressed BMSCs were cocultured with HUVECs to examine their role in angiogenesis. The molecule mechanism of tsRNA-15797-modified exosomes was explored by RNA sequencing, dual-luciferase assay, and immunofluorescence.

Results

A tRNA-derived small RNA tsRNA-15797 was down-regulated in plasma exosomes of ONFH patients. We found the effects of BMSCs-derived exosomes on accelerating HUVECs angiogenesis and migration, which were further enhanced after overexpressing tsRNA-15797. Besides, overexpression of tsRNA-15797 would lead to down-regulation of LFNG correlated with angiogenesis. tsRNA-15797 could directly interact with LFNG. We demonstrated that LNFG overexpression weakened the pro angiogenic and migratory effects of tsRNA-15797-modified BMSCs-derived exosomes.

Conclusion

We successfully constructed tsRNA-15797-modified BMSC-derived exosomes and demonstrated that it induced the angiogenesis of HUVECs by targeting the down-regulation of LFNG. Thus, tsRNA-15797-loaded BMSCs-derived exosomes may be a potential target therapy drug for ONFH.

Guiding Effect of Serum Procalcitonin (PCT) on the Antibiotic Application to Patients with Sepsis

BACKGROUND

This study aimed to investigate the guiding effect of serum procalcitonin (PCT) on the antibiotic application to patients with sepsis.

METHODS

Ninety-eight patients with sepsis treated in Renmin Hospital of Wuhan University, China from 2015-2017 were enrolled. They were divided into two equal groups of control group and the observation group. Patients in the observation group received the antibiotic therapy guided by PCT while patients in the control group received the regular antibiotic therapy. The conventional indexes, prognosis and clinical effects of the two groups were compared.

RESULTS

There were no statistical significance in the differences of the Acute Physiology and Chronic Health Evaluation II (APACHE-II) scores C-reactive protein (CRP) and white blood cell count (WBC) levels between the two groups. The duration of the antibiotic application to patients in the observation group was (7.74±0.61) d which was (10.22±0.78) d shorter than that to patients in the control group. The difference was statistically significant (P<0.05). The Intensive Care Unit (ICU) stay time and the hospital stays of patients in the observation group were shorter than those of patients in the control group. The difference had statistical significance (P<0.05). The difference in 30-day-recurrence rate and 30 day-mortality of the patients in the two groups had no statistical significance. There was statistically significant difference in the comparison of the clinical effects between the two groups.

CONCLUSION

Guiding effects of the serum PCT on the application of antibiotics to patients with sepsis shorten the usage time of the antibiotics, ICU stay time and hospital stays.

[Diagnostic knowledge and skills of parasitic diseases based on competition of professional personnel in Jiangsu Province, China]

Objective To understand the integrated ability of parasitic disease prevention and control of professional personnel of Jiangsu Province through the contest. Methods Totally 56 players from the whole province were selected, and all the players participated in the contest. The theory knowledge and skill scores were collected and the statistical analyses were conducted. Results The average theoretical score of the participants was 88.86±15.56 and the passing rate was 91.1%. The average skill operating score was 69.16±16.01 and the passing rate was 67.9%. The average Plasmodium microscopy score was 16.54±8.09 and the passing rate was 50%. The average helminth egg microscopy score was 34.27±10.66 and the passing rate was 67.9%. There were statistical differences among the age groups and different levels of schistosomiasis endemic situation (F = 5.10, 6.39, both P < 0.01). The theoretical knowledge including schistosomiasis, malaria, hydatid disease and others and the score rates were 91.07%, 90.94%, 85.83% and 90.93%, respectively. The hydatid disease score rate was lower (χ² = 19.17, P < 0.01). The radar chart displayed that the score rates of tabletting and microscopy test in Kato-Katz film production, malaria blood film production and microscopy test were all low. Conclusion In Jiangsu Province, the participants have higher score in the theory test. However, they have lower skill test score, especially in the parasite species identification. The operational skills still need to be strengthened for center for disease control (CDC) participants.

Thickness-induced structural phase transformation of layered gallium telluride

We report a spontaneous phase transformation of GaTe, occurring when the bulk is exfoliated to a few layers. The results demonstrate the crucial role of interlayer interactions in the structural stability.

Degradation of the photosystem I complex during photoinhibition

Exposure of isolated photosystem I (PSI) complexes to illumination (2300 microE m(-2) s(-1)) for various periods of time resulted in striking changes in their absorption spectra. A 6 nm blueshift of the absorption maximum in the red was detected after 100 min illumination. The fourth derivative of the absorption spectra verifies that the main change of the red peak was attributed to the 682 nm absorption band. Further, it was also shown that a shoulder in the absorption spectra located around 470 nm decreased after the first 5 min of illumination and almost disappeared after 40 min illumination, suggesting that chlorophyll b bound to light-harvesting complex I (LHCI) is also sensitive to excess light. A maximum inhibitory effect on the oxygen uptake rates and a strong stimulation were observed when the PSI complexes were exposed to illumination for about 20 and 40 min, respectively. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis shows that LHCI-680 started to degrade during the first 5 min of illumination and almost completely disappeared after 40 min of illumination. These observations demonstrated that LHCI was more sensitive to illumination than the PsaA/B subunits which also presented some degradation signs after 40 min illumination. In addition, insoluble-cohesive-denatured proteins also appeared between the stacking and resolving gel after prolonged illumination (100 min). A photoprotective function of LHCI for the PSI reaction center is proposed.

Adjusting the evaluation limit for broad-band whole-body vibration

The vibration levels of 87 axes in 29 conventional vehicles were measured, recorded, and analyzed. The mean deviation of the overall frequency-weighted vibration levels (Lw) and the greatest single one-third octave band frequency-weighted vibration levels (Lwi-max) in corresponding axes were statistically calculated. The results showed that the vehicle vibrations were broad-band vibrations. The mean deviation of Lw - Lwi-max is 6 dB. This article suggests a 6 dB value as an appropriate adjustment value for evaluating broad-band whole-body vibrations of vehicles when using the most sensitive limits given in International Organization for Standardization document 2631/1.

Discharge response of cerebellar Purkinje cells to stimulation of C-fiber in cat saphenous nerve

Experiments were performed in cats under chloralose anaesthesia and immobilized by Flaxedil. The discharge responses of cerebellar Purkinje cells (PC) were recorded with a microelectrode. The spontaneous activities of PC consisted of simple spike (SS) and complex spike (CS). When the saphenous nerve was stimulated at a low intensity, which elicited the A-fiber input only, the discharge responses (A-CED) consisted of an early component with short latency and late component with long latency in PC-SS and PC-CS. After A-fibers were blocked selectively by the polarizing current, the stimulation at the strength of C-fiber suprathreshold evoked the characteristic responses (C-CED) of PC-SS and PC-CS with middle latency. However, the C-CED could not be evoked by the inputs of A- and C-fibers simultaneously. These results suggested that the pure C-fiber input reaching the cerebellar PC passed through not only climbing fibers, but also mossy fibers, and elicited the characteristic responses (C-CED); these responses were neither the early component nor late component of the A-CED. When A- and C-fiber were activated at the same time, the C-CED might be inhibited by the A-fiber inputs.

An autopsy case of sudden unexpected death due to atherosclerotic coronary heart disease associated with simple right ventricular outflow tract stenosis

A case of a 35-year-old male who died suddenly after a blow on the chest by his opponent during a quarrel. From both the clinical and autoptical examinations there was no evidence of trauma found anywhere, even in the chest. The heart was the only one of all the internal organs whereon significant pathologic changes were observed during autopsy. It's lesions were as follows: (I) The right ventricle was greatly enlarged simply due to the simple right ventricular outflow tract stenosis (SRVOTS); the heart weight was 587 g. (II) All the main trunks of coronary arteries were involved by atherosclerosis. In addition, the appearance of the lumen at the proximal end of the left anterior descending artery narrowed by an atheromatous plaque (grade II) was completely occluded by a newly formed thrombus. The authors believed that both the coronary atherosclerotic changes and the enlarged heart due to the SRVOTS played a role in the pathogenesis of death (Kelberlus, H.E. and Wellens, H.J.J., Sudden Death, Developments in Cardiovascular Medicine, Vol. 4, Martinys Nijhoff Publishers, London, 1980, pp. 34-48; Jinming, Qin, A study of cardiac sudden death (51 cases) on the clinical pathologic view, Tianjin Med., 8 (1980) 458-461). The quarrel and blow were the disposing factor.