A regenerable and reducing false-positive fluorescent switch for detection of ß-amyloid 1-42 oligomers.

The conventional fluorescence analysis methods for disease identification are vulnerable to the restriction with false-positive. Here, a fluorescent switch with high efficiency and regeneration by the black phosphorus (BP) nanosheets-regulated was developed to overcome false-positive issue in the assay of ß-amyloid1-42 oligomers (Aß) process. The Aß was rapidly recognized using the fluorescent emitter-nitrogen-doped carbon nanodots (N-CDs) under the regulation of BP nanosheets, while the N-CDs alone cannot recognize Aß without the introduction of BP. The fluorescence analysis methods exhibited a wide sensing range of 0.25-15.0 ng/mL and a low detection limit of 83 pg/mL for Aß analysis, which was superior to the reported fluorescence analysis method. Further, BP nanosheets were recycled, demonstrating the fluorescent switch with highly efficient, stable, and regenerable. This provides a new idea for developing high-efficiency and high-precision fluorescence detection platform.

Low-concentration iron promotes Klebsiella pneumoniae biofilm formation by suppressing succinic acid.

BACKGROUND: Klebsiella pneumoniae is widely distributed in water and plays a major role in both human and poultry infections. Many K. pneumoniae strains form biofilms on various surfaces, enhancing their pathogenicity and resistance to antibiotics. The water supply pipeline of chicken farms has become a hotbed for the growth of K pneumoniae biofilm because of its humid environment, and because the chicken drinking water pipeline is thin, it is easily blocked by the biofilm, and the diffused cells can cause repeated and persistent infections. Iron is vital to the growth of microorganisms and the formation of biofilms. Therefore, the aim of this study was to examine the effects of iron on K. pneumoniae biofilm formation and any associated metabolic changes to provide a rationale for reducing the formation of biofilms. RESULTS: Biofilm formation was enhanced to the greatest extent by the presence of 0.16 mM FeCl2, producing a denser structure under electron microscopy. The number of biofilm-forming and planktonic bacteria did not change, but protein and polysaccharide concentrations in the bacterial extracellular polymeric substances (EPS) were significantly increased by iron supplementation. To clarify this mechanism, intracellular metabolomic analysis was carried out, showing that the differential, down-regulated metabolites included succinic acid. The addition of 1.7 mM succinic acid counteracted the biofilm-forming effect of iron, with no bactericidal side effects. CONCLUSION: This study demonstrates the importance of succinic acid and iron in K. pneumoniae biofilms, and provides insight into the formation of K. pneumoniae biofilms and direction for the development of new antibacterial agents.

[Acupuncture based on meridian diagnosis for chronic atrophic gastritis].

OBJECTIVE: To compare the efficacy between acupoint selection of meridian diagnosis and regular acupoint selection for chronic atrophic gastritis (CAG). METHODS: A total of 70 cases of CAG were randomly divided into an observation group (35 cases, 5 cases dropped off) and a control group (35 cases, 5 dropped off). In the observation group, according to the hand diagnosis of meridians and the results of 80-channels energy determinator, based on the principle of child-mother relation acupoint combination, the luo-connecting point and back-shu points were added for excess syndrome, and the yuan-primary point, front-mu points and he-sea point of foot meridians were added for deficiency syndrome; in addition, the acupoints of the eight extraordinary meridians were added based on the nature of acupoints. In the control group, Zhongwan (CV 12), Neiguan (PC 6), Zusanli (ST 36) and Gongsun (SP 4) were selected as the primary acupoints, and additional acupoints were added according to syndrome differentiation. The two groups were treated twice a week (Tuesday and Thursday, respectively), totally for 6 months. Six months after treatment, the follow-up was conducted. The clinical symptom score, gastroenteropathy patient reported outcomes (PRO) scale score before treatment, after treatment and during follow-up as well as the score of pathological changes of gastric mucosa before and after treatment were compared between the two groups. RESULTS: After treatment and during follow-up, the clinical symptom scores and gastroenteropathy PRO scale scores were decreased in the two groups (P<0.01, P<0.001); at the follow-up, the gastroenteropathy PRO scale score in the observation group was lower than that in the control group (P<0.01). After treatment, the scores of pathological changes of gastric mucosa in the two groups were decreased (P<0.01), and the score in the observation group was lower than that in the control group (P<0.05). CONCLUSION: The acupoint selection of meridian diagnosis is superior to regular acupoint selection for CAG, which has better efficacy, more significant improvement on gastric mucosa pathology, and more stable long-term effect.

[Analysis of the clinical effect on post-stroke shoulder hand syndrome stage â treated with the along-meridian trochar acupuncture therapy].

OBJECTIVE: To compare the differences in the clinical effect on post-stroke shoulder hand syndrome (SHS) stage Ⅰ between the along-meridian trochar acupuncture therapy and the routine acupuncture therapy with filiform needles. METHODS: A total of 80 patients with post-stroke SHS stage I were divided into a treatment group (41 cases) and a control group (39 cases) according to the random number table. In the control group, the common filiform needles were used to stimulate Jianyu (LI15), Jianliao (TE14), Jianzhen (SI9), Jianzhongshu (SI15), Jianwaishu (SI14), 5 times a week, 3 weeks as 1 course. In the treatment group, along-meridian trochar acupuncture therapy was applied, 3 times a week, 3 weeks as 1 course. The patients in both groups were all treated with basic medications and routine rehabilitation training. Pain degree, edema degree, upper limb motor function and activity of daily living were observed in the two groups before the treatment, at the end of the treatment and in follow-up. At the end of treatment and in follow-up, the therapeutic effect was evaluated respectively in the patients of the two groups. RESULTS: Compared with the values before treatment, the VAS score of the upper limb was reduced obviously (P< 0.001), the score of the upper limb motor function and Barthel index were increased obviously (P<0.001, P<0.05) in the patients of the two groups, the score of edema degree of the affected limb was reduced after treatment in the patients of the treatment group (P<0.001). Compared with the control group, VAS score of the upper limb and the score of edema degree of the affected limb were obviously lower (P<0.001), and the score of the upper limb motor function and Barthel index were obviously higher in the treatment group (P<0.001). The total effective rate was 66.7% (26/39) after treatment and was 74.4% (29/39) in follow-up in the treatment group and they were 20.5% (8/39) and 28.2% (11/39) respectively in the control group. The total effective rates after treatment and in follow-up in the treatment group were all obviously higher than those in the control group respectively (P<0.001). CONCLUSION: The along-meridian trochar acupuncture therapy remarkably relieves pain and edema and improves the upper limb motor function and the activity of daily living in the patients with post-stroke shoulder hand syndrome and its clinical therapeutic effect is definite.

[Clinical study for stroke treated with meridian-collateral diagnosis and therapy by WANG Juyi].

OBJECTIVE: To compare the effect difference for stroke between meridian-collateral diagnosis and therapy by WANG Juyiand conventional acupuncture with syndrome differentiation. METHODS: Totally 148 patients were assigned into an observation group(72 cases) and a control group(76 cases) by random number table,with 10 cases dropping out in the observation group. In the observation group,meridians were examined and differentiated and then the treating meridians and acupoints were defined. Corresponding acupuncture was used according to them. In the control group,acupuncture was applied at acupoints by internal differentiation and experience. Treatment was given once a day and five times a week,with total 20 times. The motion function of limbs and coloboma degree of nerve function were assessed by Fugl-Meyer score and National Institutes of Health Stroke Score(NIHSS) before and after treatment as well as at three-month follow-up. RESULTS: After treatment,the Fugl-Meyer scores increased and the NIHSS scores decreased in the two groups compared with those before treatment(all P<0.05). At follow-up three months after treatment,Fugl-Meyer score upgraded in the observation group (P<0.05) and NIHSS score declined in the two groups (both P<0.01) than those before treatment,and NIHSS scores were statistically different between the two groups(P<0.05). CONCLUSIONS: Meridian-collateral diagnosis and therapy by WANG Juyi has better long-term efficacy when it is compared with conventional acupuncture with syndrome differentiation for motion function of limbs and nerve function of stroke.

Effects of Chinese herbal medicine serum on the apoptosis of sinoatrial node cells induced by simulated ischemia-reperfusion.

OBJECTIVE: To study the effect of Chinese herbal medicine Kangxin Fumai Granule ((see text) Granule for heart diseases) serum on the primary cultured sinoatrial node (SAN) cell apoptosis induced by simulated ischemia-reperfusion (IR). METHODS: The SAN cells removed from SAN tissue of neonatal Wistar rats were cultured and purified with differential attachment and 5'-bromodeoxyuridine (BrdU) treatment. Simulated IR model was adopted. The obtained cells were morphologically observed with inverted microscopy. By using the method of serum pharmacology, the cell apoptosis was measured with TUNEL staining qualitatively and with flow cytometry quantitatively. RESULTS: Three kinds of cells were observed in the cultured SAN cells: spindle, triangle and irregular. The spindle cells comprised the greatest proportion. The SAN cells in the model group showed moderate positive brown staining in the nucleus, and the apoptosis rate increased significantly compared to that in the control group (P < 0.01). While the SAN cells in the Kangxin Fumai Granule high-dose group did not demonstrated positive staining in the nucleus, and the apoptosis rate decreased significantly compared to that in the model group (P < 0.05). CONCLUSION: Of the cells cultured from SAN, the spindle cells were pacemaker cells of SAN in rats. Blockade and/or inhibition of the SAN cell apoptosis might be one of the important mechanisms of Kangxin Fumai Granule in preventing and treating sinoatrial injury induced by simulated IR.

[Effect of qiangxin fumai granule contained serum on sinoatrial node cells during Ca2+ overloading induced by simulated ischemia/reperfusion].

OBJECTIVE: To explore the effect of Qiangxin Fumai Granule (QFG, a Chinese herbal preparation for treatment of sick sinus syndrome) contained serum (QFG-S) on sinoatrial node cells during Ca2+ overloading induced by simulated ischemia/reperfusion. METHODS: Model Ca2+ overloading cells were established on sinoatrial node cells from newborn rats, with deprivation of oxygen and glucose to simulate ischemia and with restoration of them to simulate reperfusion. Cells were divided into 5 groups, those in the normal and model control groups were modeled directly and those in the treated groups were pre-cultured with UMEM containing respective medicines in aerobic environment for 30 mm before ischemia/reperfusion simulation. Cell Ca2+ concentration and morphology were observed by invert microscope and fluorescence spectrophotometer. RESULTS: Most cells in the model control group revealed cell edema and deformation, even abscission. By HE staining, many minimal vacuole appeared in cytoplasm, with crumpled nuclear membrane, partially damaged. While cells in the QFG-S treated group, either high-dose or low-dose, were attached grew well, with basically smooth and complete membrane and nuclear membrane, normal in size and shape. The intracellular Ca2+ concentration raised significantly after modeling, but it was much lower in the QFG-S treated group than in the model control group (P < 0.01) and it was not changed obviously in the atropine treated group. CONCLUSION: QFG-S could diminish the injury of cell induced by simulated ischemia/reperfusion, the acting mechanism for treatment of sick sinus syndrome might be related to its effect in relieving Ca2+ overloading and thus protecting cells from injury.

Effect of Qiangxin Fumai Granule () on electrophysiological functions of the sinoatrial node during ischemia-reperfusion of the right coronary artery in rabbits.

OBJECTIVE: To study the effect of the Chinese medicine Qiangxin Fumai Granule (, QFG) on electrophysiological functions of the sinoatrial node during ischemia-reperfusion (IR) of the right coronary artery in rabbits. METHODS: The right coronary artery IR model in rabbits was adopted. The modeled rabbits were randomly divided into 4 groups: the model group, the atropine group, the high-dose QFG group, and the low-dose QFG group, with 8 animals in each group. In addition, twelve rabbits were selected for the sham-operative group. The drugs were administered once via duodenal perfusion after modeling had been stabilized for 10 min. The changes in AA interval, the sinoatrial conduction time (SACT), the sinus node recovery time (SNRT), the corrected sinus node recovery time (CSNRT) and the index of sinus node recovery time (ISNRT) at different time points during ischemia and reperfusion were measured. RESULTS: The AA interval was prolonged for more than 40 ms in the model group during ischemia. Compared with the model group, the four electrophysiological parameters abovementioned in the high-dose QFG group and the low-dose QFG group were decreased to different extents at each time point (P<0.01 or P<0.05), and no statistically significant differences were found between the QFG groups and the atropine group (P>0.05). CONCLUSION: QFG is beneficial for accelerating the recovery of sinus node autorhythmicity and conduction function, so as to protect electrophysiological functions of the sinoatrial node. Accelerating the recovery of autorhythmicity and conduction function in the sinus node is considered its electrophysiological mechanism in the treatment of sinoatrial node injury induced by ischemia.

[Intervening effect of Qiangxin Fumai Granule on arrhythmia induced by right coronary artery ischemia/reperfusion in rabbits].

OBJECTIVE: To observe the development of arrhythmia induced by ischemia/reperfusion (I/R) of the right coronary artery in rabbits and the intervening effect of Chinese medicine Qiangxin Fumai Granule (QFG), a Chinese preparation for activating yang and promoting blood circulation, on it. METHODS: Rabbit right coronary artery I/R model was adopted. Forty healthy adult rabbits were randomly divided into 5 groups, the sham-operation group, the model group, the atropine group, the high-dose QFG group, and the low-dose QFG group, eight in each group. The drugs were administered via duodenal perfusion 10 min after ischemia. The changes of AA interval before and after medication were observed and the scores of arrhythmia were calculated. RESULTS: During ischemia period, AA interval prolonged for more than 40 ms in the model group, and the scores of arrhythmia showed a rising trend along with the prolonging of ischemia, with the presence of atrial-ventricular block (AVB) and aggravating of sinus and atrial arrhythmia; during reperfusion period, the incidence of AVB decreased, and AA interval somewhat decreased. The AA intervals and scores of arrhythmia in the high and low-dose QFG groups were significantly lower than those in the model group respectively (P < 0.01 or P < 0.05). CONCLUSION: QFG is beneficial for shortening AA interval and preventing arrhythmia induced by I/R.

[Effect of Qiangxin Fumai granule on myocyte apoptosis of sinus node and Bax, Bcl-2, Fas-L gene protein in rabbits of sinoatrial ischemia/reperfusion].

OBJECTIVE: To explore the molecular mechanism of Qiangxin Fumai granule (QFG, an effective Chinese composite drug) in preventing and treating sick sinus syndrome (SSS). METHOD: Rabbit model of sinoatrial ischemia/reperfusion was established by occluding and loosening the root of right coronary artery. Effect of QFG on cell apoptosis was observed by TUNEL method, and its effect on apoptotic related gene Bax, Bcl-2 and Fas-L gene protein expression was observed by immunohistochemical method. Average light density values of the expression of Bax, Bcl-2 and Fas-L of SAN cells was determined by Imagepro Plus image analysis system. RESULT: Sinoatrial injury induced by ischemia/reperfusion could cause evident sinoatrial cell apoptosis, enhance Fas-L gene protein expression and obviously enhance Bax gene protein expression, reduce Bcl-2/Bax ratio. QFG could significantly down-regulate Fas-L and Bax gene protein expression, up-regulate Bcl-2/Bax ratio, significantly inhibit and block the sinoatrial cell apoptosis. CONCLUSION: To inhibit and block the event of cell apoptosis through regulating Bax, Bcl-2 and Fas-L gene protein expression in sinoatrial node after ischemia/reperfusion might be one of the mechanisms of QFG in preventing and treating sinoatrial ischemia/reperfusion injury of SSS.