"Off-On" typed upconversion fluorescence resonance energy transfer probe for the determination of Cu2+ in tap water.

Detection of copper plays a prominent role in the environmental protection and human health. Herein, we firstly design and construct an "off-on" upconversion fluorescence resonance energy transfer (UFRET) probe with low toxicity for the Cu2+ determination by using NaYF4: Yb3+, Er3+ upconversion nanoparticles (UCNPs) and Au NPs. UCNPs with positive charge and Au NPs with negative charge are respectively employed as the donor and acceptor, and bound together to form UFRET probe. The upconversion fluorescence quenching of UCNPs occurs by Au NPs through FRET (defined as "off" state). When Cu2+ exists in samples, Cu2+ reacts with 4-mercaptobenzoic acid (4-MBA) capped on the surface of Au NPs to make Au NPs detach from UCNPs, leading to the termination of FRET and the recovery of upconversion fluorescence (defined as "on" state). "Off-on" typed UFRET probe has excellent sensing performances, including linear range of 0.02-1 µM Cu2+ concentration, the limit of detection of 18.2 nM, high selectivity to Cu2+ and good recovery. The probe has been successfully used to determine Cu2+ in spiked tap water with satisfactory results. The probe will provide theoretical and technical support for the design of new sensitive heavy metal ion detection probe.

Efficacy of abdominal ultrasound inspection in the diagnosis and prognosis of neonatal necrotizing enterocolitis.

OBJECTIVE: This study aimed to identify the most useful ultrasound (US) features associated with definite neonatal necrotizing enterocolitis (NEC) and their prognostic values, particularly the calculated markers combined with important features. METHODS: A total of 213 suspected NEC cases were collected from the neonatal department of our hospital from January 2015 to August 2017. Each infant received both X-ray and US examinations. RESULTS: No differences were found in sex composition and delivery modes between groups. NEC-positive neonates had poorer prognosis compared to negative ones. The NEC group showed a higher frequency of abnormal signals. US showed higher NEC-related frequencies in different parameters. A variable (named predictor in US [PUS]) with five features was constructed. For NEC diagnosis, this variable provided a much higher area under the curve Q2 (AUC) (0.965) than other parameters. In this model, PUS had a cutoff value of 0.376 with a 0.900 sensitivity and 0.922 specificity. In prognosis, the closest factors were selected to draw a receiver operating characteristic curve, as well as a novel calculated variable US prognostic (USPro) marker. USPro had a much higher AUC (0.86) than other single features and showed a cutoff value of 0.18145, with 0.75 sensitivity and 0.84 specificity. This variable had a weaker power in prognosis when compared with PUS in diagnosis. CONCLUSIONS: The application of abdominal color Doppler US can provide high accuracy and sensitivity in NEC diagnosis and also contribute to its prognosis, without induction of radiation. Suspected neonates should be examined using this technique as early as possible.

Efficacy of abdominal ultrasound inspection in the diagnosis and prognosis of neonatal necrotizing enterocolitis

OBJECTIVE: This study aimed to identify the most useful ultrasound (US) features associated with definite neonatal necrotizing enterocolitis (NEC) and their prognostic values, particularly the calculated markers combined with important features. METHODS: A total of 213 suspected NEC cases were collected from the neonatal department of our hospital from January 2015 to August 2017. Each infant received both X-ray and US examinations. RESULTS: No differences were found in sex composition and delivery modes between groups. NEC-positive neonates had poorer prognosis compared to negative ones. The NEC group showed a higher frequency of abnormal signals. US showed higher NEC-related frequencies in different parameters. A variable (named predictor in US [PUS]) with five features was constructed. For NEC diagnosis, this variable provided a much higher area under the curve Q2 (AUC) (0.965) than other parameters. In this model, PUS had a cutoff value of 0.376 with a 0.900 sensitivity and 0.922 specificity. In prognosis, the closest factors were selected to draw a receiver operating characteristic curve, as well as a novel calculated variable US prognostic (USPro) marker. USPro had a much higher AUC (0.86) than other single features and showed a cutoff value of 0.18145, with 0.75 sensitivity and 0.84 specificity. This variable had a weaker power in prognosis when compared with PUS in diagnosis. CONCLUSIONS: The application of abdominal color Doppler US can provide high accuracy and sensitivity in NEC diagnosis and also contribute to its prognosis, without induction of radiation. Suspected neonates should be examined using this technique as early as possible.

Cardioprotection of Rosuvastatin Pre-conditioning on Myocardial Ischemia / Reperfusion Injury in a Rat Model

Abstract This study aimed to investigate the cardioprotection of rosuvastatin pre-conditioning (R-Pre) in a rat model of myocardial ischemia / reperfusion (I/R). Male SD rats were assigned into three groups: sham group, I/R group and R-Pre group. Rats in I/R group and R-Pre group received ischemia for 30 min and reperfusion for 2 h. In R-Pre group, rats received intragastrical administration with rosuvastatin at 5 mg/kg once daily for 1 week. After 2-h reperfusion, the cardiac function was detected by ultrasonography; the blood was collected for biochemical analysis; the heart was collected for the TUNEL staining and immunohistochemistry for Bcl-2 and Bax. Our results showed rosuvastatin pre-conditioning for 1 week could significantly reduce the infarct ratio and improve the cardiac function after myocardial I/R injury, in which attenuation of oxidative stress and cell apoptosis played an important role. Our study provides evidence on the cardioprotection of rosuvastatin pre-conditioning and highlight the use of rosuvastatin before cardiopulmonary bypass.

A study of community-acquired Mycoplasma pneumoniae in Yantai, China.

INTRODUCTION: Community-acquired pneumonia (CAP) is a global disease responsible for a large number of deaths, with significant economic impact. As diagnostic tools have increased in sensitivity, understanding of the etiology of CAP has begun to change. Mycoplasma pneumoniae is one of the major pathogens causing CAP. Macrolides and related antibiotics are first-line treatments for M. pneumoniae. Macrolide resistance has been spreading for 15 years and now occurs in worldwide. We undertook the first study on macrolide resistance of M. pneumoniae in Yantai. This may be helpful to determine the appropriate therapy for CAP in this population. OBJECTIVE: To investigate the rate and mechanism of macrolide resistance in Yantai. METHODS: Pharyngeal swab samples were collected from adult CAP patients. Samples were assayed by polymerase chain reaction (PCR) and cultivated to test for M. pneumoniae. Nested PCR was used to specifically amplify M. pneumoniae 23S rRNA gene fragments containing mutations, and amplicons were analyzed by CE-SSCP for macrolide resistance mutations. Results were confirmed by sequencing. Twenty-seven strains of M. pneumoniae were isolated and the activities of nine antibiotics against M. pneumoniae were tested in vitro. RESULTS: Out of 128 samples tested, 27 were positive for M. pneumoniae. Mycoplasma 100% macrolides resistance to Mycoplasma pneumoniae. The mechanism of macrolides resistance was A2063G point mutation in the sequence directly binding to macrolides in the 23S rRNA V domain in vitro. The mean pyretolytic time for the fluoroquinolone group was 4.7 ±2.9 d, which was significantly shorter than 8.2 ±4.1 d for the azithromycin group. CONCLUSIONS: Macrolides are not the first-line treatment for M. pneumoniae respiratory tract infections in Yantai.

INTRODUCCIÓN: Neumonía adquirida por en la comunidad (NAC) es una enfermedad responsable por un gran número de muertes y un impacto económico importante. Debido a que el diagnostico incrementó la sensibilidad, se cambió la etiología de la NAC. Adicionalmente, Mycoplasma pneumoniae es uno de los patógenos que causan la NAC. Los macrólidos y antibióticos relacionados son la primera línea de tratamiento para M. pneumoniae. La resistencia a macrólidos se aumentó en los últimos 15 años y ahora se encuentra distribuido en todo el mundo. Nosotros realizamos el primer estudio de resitencia a M. pneumoniae a los macrólidos en Yantai. Esto podría ser útil para determinar una terapia apropiada para NAC en esta población. OBJETIVO: Investigar la tasa y el mecanismo para la resitencia a los macrólidos en Yantai. MÉTODOS: Se colectaron muestras faringeas usando un hisopo. Las muestras se analizaron mediante la reacción en cadena de la polimerasa (PCR) y por cultivo para M. pneumoniae. Se uso una PCR anidad para amplificar fragmentos del gen 23S rRNA especifico con las mutaciones para M. pneumoniae. Se analizaron amplicomes por CE-SSCP para determinar la resitencia a los macrólidos. Estos resultados se confirmaron por secuenciación. Se aislaron 27 cepas de M. pneumoniae y se probaron nueve antibióticos in vitro. RESULTADOS: De 128 muestras, 27 fueron positivas para M. pneumoniae. Se determinó una resistencia a macrólidos por Mycoplasma del 100%. Los mecanismos de esta resitencia fue una mutacion punctual A2063G en la secuencia que se une directamente a los macrólidos en el dominio 23S rRNA V in vitro. El tiempo piotolítico medio para el grupo de fluoroquinolonas fue 4.7 ±2.9 d, que fue significativamente más corto que para el grupo de azitromicina: 8.2 ±4.1 d. CONCLUSIONES: Los macrólidos no son la primera linea de tratamiento para las infecciones del tracto respiratorio contra M. pneumoniae respiratory tract infections en Yantai.

A study of community-acquired Mycoplasma pneumoniae in Yantai, China / Estudio de Mycoplasma pneumoniae adquirido en la comunidad en Yantai, China

Abstract Introduction: Community-acquired pneumonia (CAP) is a global disease responsible for a large number of deaths, with significant economic impact. As diagnostic tools have increased in sensitivity, understanding of the etiology of CAP has begun to change. Mycoplasma pneumoniae is one of the major pathogens causing CAP. Macrolides and related antibiotics are first-line treatments for M. pneumoniae. Macrolide resistance has been spreading for 15 years and now occurs in worldwide. We undertook the first study on macrolide resistance of M. pneumoniae in Yantai. This may be helpful to determine the appropriate therapy for CAP in this population. Objective: To investigate the rate and mechanism of macrolide resistance in Yantai. Methods: Pharyngeal swab samples were collected from adult CAP patients. Samples were assayed by polymerase chain reaction (PCR) and cultivated to test for M. pneumoniae. Nested PCR was used to specifically amplify M. pneumoniae 23S rRNA gene fragments containing mutations, and amplicons were analyzed by CE-SSCP for macrolide resistance mutations. Results were confirmed by sequencing. Twenty-seven strains of M. pneumoniae were isolated and the activities of nine antibiotics against M. pneumoniae were tested in vitro. Results: Out of 128 samples tested, 27 were positive for M. pneumoniae. Mycoplasma 100% macrolides resistance to Mycoplasma pneumoniae. The mechanism of macrolides resistance was A2063G point mutation in the sequence directly binding to macrolides in the 23S rRNA V domain in vitro. The mean pyretolytic time for the fluoroquinolone group was 4.7 ±2.9 d, which was significantly shorter than 8.2 ±4.1 d for the azithromycin group. Conclusions: Macrolides are not the first-line treatment for M. pneumoniae respiratory tract infections in Yantai.

Resumen Introducción: Neumonía adquirida por en la comunidad (NAC) es una enfermedad responsable por un gran número de muertes y un impacto económico importante. Debido a que el diagnostico incrementó la sensibilidad, se cambió la etiología de la NAC. Adicionalmente, Mycoplasma pneumoniae es uno de los patógenos que causan la NAC. Los macrólidos y antibióticos relacionados son la primera línea de tratamiento para M. pneumoniae. La resistencia a macrólidos se aumentó en los últimos 15 años y ahora se encuentra distribuido en todo el mundo. Nosotros realizamos el primer estudio de resitencia a M. pneumoniae a los macrólidos en Yantai. Esto podría ser útil para determinar una terapia apropiada para NAC en esta población. Objetivo: Investigar la tasa y el mecanismo para la resitencia a los macrólidos en Yantai. Métodos: Se colectaron muestras faringeas usando un hisopo. Las muestras se analizaron mediante la reacción en cadena de la polimerasa (PCR) y por cultivo para M. pneumoniae. Se uso una PCR anidad para amplificar fragmentos del gen 23S rRNA especifico con las mutaciones para M. pneumoniae. Se analizaron amplicomes por CE-SSCP para determinar la resitencia a los macrólidos. Estos resultados se confirmaron por secuenciación. Se aislaron 27 cepas de M. pneumoniae y se probaron nueve antibióticos in vitro. Resultados: De 128 muestras, 27 fueron positivas para M. pneumoniae. Se determinó una resistencia a macrólidos por Mycoplasma del 100%. Los mecanismos de esta resitencia fue una mutacion punctual A2063G en la secuencia que se une directamente a los macrólidos en el dominio 23S rRNA V in vitro. El tiempo piotolítico medio para el grupo de fluoroquinolonas fue 4.7 ±2.9 d, que fue significativamente más corto que para el grupo de azitromicina: 8.2 ±4.1 d. Conclusiones: Los macrólidos no son la primera linea de tratamiento para las infecciones del tracto respiratorio contra M. pneumoniae respiratory tract infections en Yantai.

Different models in predicting the short-term prognosis of patients with hepatitis B virus-related acute-on-chronic liver failure.

BACKGROUND AND AIMS: Effective assessing the prognosis of patients with end-stage liver disease is always challenging. This study aimed to investigate the accuracy of different models in predicting short-term prognosis of patients with hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACLF). MATERIAL AND METHODS: We retrospectively evaluated survival of a cohort of patients with at least 3-month follow up. The receiver-operating-characteristic curves (ROC) were drawn for Child-Turcotte-Pugh (CTP) classification, King's College Hospital (KCH) criteria, model for end-stage liver disease (MELD), MELD combined with serum sodium (Na) concentration (MELDNa), integrated MELD (iMELD) and logistic regression model (LRM). RESULTS: Of the 273 eligible patients, 152 patients (55.7%) died within 3-month follow up. In cirrhotic patients (n = 101), the AUCs of LRM (0.851), MELDNa (0.849), iMELD (0.845) and MELD (0.840) were all significantly higher than those of KCH criteria (0.642) and CTP (0.625) (all p < 0.05), while the differences among LRM, MELD, MELDNa and iMELD were not significant, and the most predictive cutoff value was 0.5176 for LRM, 30 for MELDNa, 47.87 for iMELD and 29 for MELD, respectively. In non-cirrhotic patients (n = 172), the AUC of LRM (0.897) was significantly higher than that of MELDNa (0.776), iMELD (0.768), MELD (0.758), KCH criteria (0.647) and CTP (0.629), respectively (all p < 0.05), and the most predictive cutoff value for LRM was -0.3264. CONCLUSIONS: LRM, MELD, MELDNa and iMELD are with similar accuracy in predicting the shortterm prognosis of HBV-ACLF patients with liver cirrhosis, while LRM is superior to MELD, MELDNa and iMELD in predicting the short-term prognosis of HBV-ACLF patients without liver cirrhosis.

Formation of cubane-like photodimers from 2-naphthalenecarbonitrile.

Irradiation of 2-naphthalenecarbonitrile (2-NpCN) in solution with a light lambda > 280 nm results in the formation of three rigid cubane-like photodimers, anti-head-to-head 1, anti-head-to-tail 2, and syn-head-to-tail 3, which are not in line with the previously recognized regioselectivity. These cubane-like photodimers have been well characterized by spectroscopic investigation and/or X-ray crystal structural analysis in this work. Moreover, the separation of the optically pure enantiomers of 1, 2, and 3 has been achieved by HPLC resolution.