Measurements of All-Particle Energy Spectrum and Mean Logarithmic Mass of Cosmic Rays from 0.3 to 30 PeV with LHAASO-KM2A

We present the measurements of all-particle energy spectrum and mean logarithmic mass of cosmic rays in the energy range of 0.3-30 PeV using data collected from LHAASO-KM2A between September 2021 and December 2022, which is based on a nearly composition-independent energy reconstruction method, achieving unprecedented accuracy. Our analysis reveals the position of the knee at 3.67±0.05±0.15  PeV. Below the knee, the spectral index is found to be -2.7413±0.0004±0.0050, while above the knee, it is -3.128±0.005±0.027, with the sharpness of the transition measured with a statistical error of 2%. The mean logarithmic mass of cosmic rays is almost heavier than helium in the whole measured energy range. It decreases from 1.7 at 0.3 PeV to 1.3 at 3 PeV, representing a 24% decline following a power law with an index of -0.1200±0.0003±0.0341. This is equivalent to an increase in abundance of light components. Above the knee, the mean logarithmic mass exhibits a power law trend towards heavier components, which is reversal to the behavior observed in the all-particle energy spectrum. Additionally, the knee position and the change in power-law index are approximately the same. These findings suggest that the knee observed in the all-particle spectrum corresponds to the knee of the light component, rather than the medium-heavy components.

Measurement of Ultra-High-Energy Diffuse Gamma-Ray Emission of the Galactic Plane from 10 TeV to 1 PeV with LHAASO-KM2A

The diffuse Galactic γ-ray emission, mainly produced via interactions between cosmic rays and the interstellar medium and/or radiation field, is a very important probe of the distribution, propagation, and interaction of cosmic rays in the Milky Way. In this Letter, we report the measurements of diffuse γ rays from the Galactic plane between 10 TeV and 1 PeV energies, with the square kilometer array of the Large High Altitude Air Shower Observatory (LHAASO). Diffuse emissions from the inner (15°10  TeV). The energy spectrum in the inner Galaxy regions can be described by a power-law function with an index of -2.99±0.04, which is different from the curved spectrum as expected from hadronic interactions between locally measured cosmic rays and the line-of-sight integrated gas content. Furthermore, the measured flux is higher by a factor of ∼3 than the prediction. A similar spectrum with an index of -2.99±0.07 is found in the outer Galaxy region, and the absolute flux for 10≲E≲60  TeV is again higher than the prediction for hadronic cosmic ray interactions. The latitude distributions of the diffuse emission are consistent with the gas distribution, while the longitude distributions show clear deviation from the gas distribution. The LHAASO measurements imply that either additional emission sources exist or cosmic ray intensities have spatial variations.

[Update points for the 2022 edition of the European Association for the Study of Liver Diseases Clinical Practice Guidelines for the Management of Hepatic Encephalopathy and comparison with China's 2018 edition guidelines]

The European Association for the Study of Liver Diseases issued the "Clinical Practice Guidelines for the Management of Hepatic Encephalopathy" in 2022, which included recommendations for clinical diagnosis, assessment, treatment, management, and prevention. The Society's "Hepatic Encephalopathy Clinical Practice Guidelines in Chronic Liver Disease," which was last published in 2014, and the "Guidelines for the Diagnosis and Treatment of Hepatic Encephalopathy in Cirrhosis," which the Chinese Society of Hepatology, Chinese Medical Association, released in 2018, have certain differences and updates in terms of comparison to terminology, grading and classification, diagnosis, clinical evaluation and treatment, management, and prevention. Herein, the updated points of this guideline and the differences between it and our nation's guidelines are summarized in order to refine and understand the guiding role of the new version of the guideline for the clinical treatment of hepatic encephalopathy and provide aid for standardizing clinical diagnosis and treatment.

A tera-electron volt afterglow from a narrow jet in an extremely bright gamma-ray burst

Some gamma-ray bursts (GRBs) have a tera-electron volt (TeV) afterglow, but the early onset of this has not been observed. We report observations with the Large High Altitude Air Shower Observatory of the bright GRB 221009A, which serendipitously occurred within the instrument field of view. More than 64,000 photons >0.2 TeV were detected within the first 3000 seconds. The TeV flux began several minutes after the GRB trigger, then rose to a peak about 10 seconds later. This was followed by a decay phase, which became more rapid ~650 seconds after the peak. We interpret the emission using a model of a relativistic jet with half-opening angle ~0.8°. This is consistent with the core of a structured jet and could explain the high isotropic energy of this GRB.

Dual-channel compressed ultrafast photography for Z-pinch dynamic imaging

The compressed ultrafast photography (CUP) can capture non-repetitive time-evolving events at 7 × 10¹³ fps, which is anticipated to find a diverse range of applications in physics, biomedical imaging, and materials science. The feasibility of diagnosing ultrafast phenomenon of Z-pinch by using the CUP has been analyzed in this article. Specifically, a dual-channel CUP design has been adopted for acquiring high quality reconstructed images and the strategies of identical masks, uncorrelated masks, and complementary masks have been compared. Furthermore, the image of the first channel was rotated by 90° to balance the spatial resolution between the sweep direction and the non-sweep direction. Both five synthetic videos and two simulated Z-pinch videos were chosen as the ground truth to validate this approach. The average peak signal to noise ratio of the reconstruction results is 50.55 dB for the self-emission visible light video and 32.53 dB for the laser shadowgraph video with unrelated masks (rotated channel 1). The simulation results show that the time-space-evolving process of plasma distribution can be well retold, and the phenomenon of plasma instability can be accurately diagnosed by the dual-channel CUP with unrelated masks (rotated channel 1). This study may promote the practical applications of the CUP in the field of accelerator physics.

Constraints on Heavy Decaying Dark Matter from 570 Days of LHAASO Observations

The kilometer square array (KM2A) of the large high altitude air shower observatory (LHAASO) aims at surveying the northern γ-ray sky at energies above 10 TeV with unprecedented sensitivity. γ-ray observations have long been one of the most powerful tools for dark matter searches, as, e.g., high-energy γ rays could be produced by the decays of heavy dark matter particles. In this Letter, we present the first dark matter analysis with LHAASO-KM2A, using the first 340 days of data from 1/2-KM2A and 230 days of data from 3/4-KM2A. Several regions of interest are used to search for a signal and account for the residual cosmic-ray background after γ/hadron separation. We find no excess of dark matter signals, and thus place some of the strongest γ-ray constraints on the lifetime of heavy dark matter particles with mass between 10^{5} and 10^{9}  GeV. Our results with LHAASO are robust, and have important implications for dark matter interpretations of the diffuse astrophysical high-energy neutrino emission.

[A meta-analysis on prevalence of primary angle-closure glaucoma in the middle-aged and elderly chinese population]

Objective: To evaluate the prevalence and relevant factors of primary angle-closure glaucoma (PACG) in the middle-aged and elderly (40 years old and above) Chinese population. Methods: Epidemiological literature (of English and/or Chinese language) on prevalence of PACG in China between 2000 and 2022 were retrieved from PubMed, Embase, Web of Science, CNKI, and Wanfang database. Two researchers conducted the process of document retrieval, inclusion, quality assessment and data extraction independently based on inclusion and exclusion criteria. Disagreement was resolved by consensus with a third researcher. The heterogeneity among studies was assessed by using the I² statistics, and a corresponding model was used for the meta-analysis. Subgroup analysis (gender, age, survey date, place of residence, diagnostic criteria, and temperature zone), as well as sensitivity analysis and publication bias analysis, were conducted. Results: Twenty-three studies were included in this research. Among them, eight were of high-quality and fifteen were of middle-quality. In the past 20 years, the PACG prevalence in middle-aged and elderly (40 years and older) Chinese population was 1.35% (95%CI:1.08% to 1.61%). Chinese women (1.40%) were more likely to have PACG than men (0.96%, P<0.01). The PACG prevalence had a positive correlation with age (P<0.01). The prevalence was similar between urban (1.3%) and rural (1.2%, P=0.61) areas. The PACG prevalence from studies in which the diagnostic criteria of PACG requested the symptom of vision or optic nerve damage (1.1%) was lower than that those without such requirement (1.7%, P<0.01). In mid-temperate zone, the prevalence was higher (1.7%, P=0.02). Conclusions: The PACG prevalence in middle-aged and elderly (40 years old and above) Chinese population was 1.35% in the last 20 years. The prevalence of PACG varies across age, regions, and other variations. This risk is higher in the elderly, women, and people in cold regions among Chinese population.

[Efficacy and safety of total neoadjuvant therapy versus neoadjuvant chemoradiotherapy in the treatment of locally advanced rectal cancer: a meta-analysis]

Objective: To systematically evaluate the efficacy and safety of total neoadjuvant therapy (TNT) in the comprehensive treatment of locally advanced rectal cancer. Methods: Literatures were screened from PubMed, Embase, Web of Science, Cochrane Library, CBM, Wanfang Data, VIP and CNKI from the inception date to May 2021 to collect the randomized controlled clinical trials (RCTs) of TNT followed by total mesorectal excision (TME) versus neoadjuvant chemotherapy (nCRT) followed by TME in the treatment of locally advanced rectal cancer. The data of overall survival, disease-free survival, R0 radical resection rate, pathological complete response (pCR) rate, T downstaging rate, the incidence of adverse events ≥ grade III, including neutropenia, nausea and vomiting, diarrhea, radiation dermatitis and nervous system toxicity, and the morbidity of complications within postoperative 30 days of the two groups were extracted from the included literatures. Review Manager 5.3 software was utilized for statistical meta-analysis. Results: Nine RCTs were finally enrolled including 2430 patients. Meta-analysis results showed that compared with nCRT group, patients in TNT group had longer overall survival (HR=0.80, 95%CI: 0.65-0.97, P=0.03) and higher pCR rate (RR=1.73, 95%CI: 1.44-2.08, P<0.01) with significant differences. Besides, there were no significant differences between two groups in disease-free survival (HR=0.86, 95%CI:0.71-1.05, P=0.14), R0 radical resection rate (RR=1.02, 95%CI: 0.99-1.06, P=0.17) and T downstaging rate (RR=1.04, 95%CI: 0.89-1.22, P=0.58) between two groups. In terms of treatment safety, the incidence of adverse events ≥ grade III (RR=1.09, 95%CI: 0.70-1.70, P=0.70) and morbidity of complications within postoperative 30 days (RR=1.07, 95%CI: 0.97-1.18, P=0.19) did not significantly differ between two groups. Conclusions: In the treatment of locally advanced rectal cancer, TNT may bring more survival benefits than nCRT and does not increase the incidence of adverse events and postoperative complications. Therefore, TNT could be used as a recommended treatment for patients with locally advanced rectal cancer.

Exploring Lorentz Invariance Violation from Ultrahigh-Energy γ Rays Observed by LHAASO

Recently, the LHAASO Collaboration published the detection of 12 ultrahigh-energy γ-ray sources above 100 TeV, with the highest energy photon reaching 1.4 PeV. The first detection of PeV γ rays from astrophysical sources may provide a very sensitive probe of the effect of the Lorentz invariance violation (LIV), which results in decay of high-energy γ rays in the superluminal scenario and hence a sharp cutoff of the energy spectrum. Two highest energy sources are studied in this work. No signature of the existence of the LIV is found in their energy spectra, and the lower limits on the LIV energy scale are derived. Our results show that the first-order LIV energy scale should be higher than about 10^{5} times the Planck scale M_{Pl} and that the second-order LIV scale is >10^{-3}M_{Pl}. Both limits improve by at least one order of magnitude the previous results.

[Efficacy of the XEN gel stent on intraocular pressure lowering in glaucoma patients]

Objective: To evaluate the efficacy and safety of the XEN gel implant in the treatment of glaucoma. Methods: It was a retrospective case series study. Eight patients (8 eyes) in the First Affiliated Hospital of Fujian Medical University from January 2020 to September 2020 were included, including six males and two females, aged 29 to 74 years. The patients treated with the XEN gel implanting for glaucoma. After detailed ophthalmic examination, all the patients met the surgical indications for the XEN gel implanting. Preoperative and postoperative intraocular pressure (IOP), anterior segment and fundus examination results, medication, and surgical complications were evaluated. Results: There were seven patients with primary open-angle glaucoma and one patient with glaucomatocyclitic syndrome. Five patients had received anti-glaucoma surgeries, and the remaining three patients had not received surgical treatment. All XEN gel stents were implanted successfully. All patients were followed up for 4 to 12 months. The preoperative maximum IOP ranged from 11 to 44 mmHg (median, 28 mmHg, 1 mmHg=0.133 kPa), and the IOP was 10 to 18 mmHg (median, 13 mmHg) at the last follow-up. Two to 4 types of medication were used for glaucoma preoperatively (median, 3), while 0 to 2 types (median, 0) were used at the last follow-up. During the follow-up, 7 cases were completely successful and only one case failed. Intraoperative hemorrhage occurred in two patients, and after effective treatment, the IOP decreased to below 20 mmHg. One patient was found to have an increased IOP with the XEN luminal obstruction, and the XEN drainage tube was recanalized. The IOP was about 10 mmHg at the last follow-up, and no anti-glaucoma drugs were used, but the surgery was assessed as failure by standard. The remaining patients had no other serious complications. Conclusion: This preliminary study shows that the XEN gel drainage may be a safe and effective treatment for patients with glaucoma. (Chin J Ophthalmol, 2021, 57: 679-684).

Peta-electron volt gamma-ray emission from the Crab Nebula

The Crab Nebula is a bright source of gamma rays powered by the Crab Pulsar's rotational energy through the formation and termination of a relativistic electron-positron wind. We report the detection of gamma rays from this source with energies from 5 × 10^-4 to 1.1 peta-electron volts with a spectrum showing gradual steepening over three energy decades. The ultrahigh-energy photons imply the presence of a peta-electron volt electron accelerator (a pevatron) in the nebula, with an acceleration rate exceeding 15% of the theoretical limit. We constrain the pevatron's size between 0.025 and 0.1 parsecs and the magnetic field to ≈110 microgauss. The production rate of peta-electron volt electrons, 2.5 × 10³⁶ ergs per second, constitutes 0.5% of the pulsar spin-down luminosity, although we cannot exclude a contribution of peta-electron volt protons to the production of the highest-energy gamma rays.

Extended Very-High-Energy Gamma-Ray Emission Surrounding PSR J0622+3749 Observed by LHAASO-KM2A

We report the discovery of an extended very-high-energy (VHE) gamma-ray source around the location of the middle-aged (207.8 kyr) pulsar PSR J0622+3749 with the Large High-Altitude Air Shower Observatory (LHAASO). The source is detected with a significance of 8.2σ for E>25  TeV assuming a Gaussian template. The best-fit location is (right ascension, declination) =(95.47°±0.11°,37.92°±0.09°), and the extension is 0.40°±0.07°. The energy spectrum can be described by a power-law spectrum with an index of -2.92±0.17_{stat}±0.02_{sys}. No clear extended multiwavelength counterpart of the LHAASO source has been found from the radio to sub-TeV bands. The LHAASO observations are consistent with the scenario that VHE electrons escaped from the pulsar, diffused in the interstellar medium, and scattered the interstellar radiation field. If interpreted as the pulsar halo scenario, the diffusion coefficient, inferred for electrons with median energies of ∼160  TeV, is consistent with those obtained from the extended halos around Geminga and Monogem and much smaller than that derived from cosmic ray secondaries. The LHAASO discovery of this source thus likely enriches the class of so-called pulsar halos and confirms that high-energy particles generally diffuse very slowly in the disturbed medium around pulsars.

Ultrahigh-energy photons up to 1.4 petaelectronvolts from 12 γ-ray Galactic sources

The extension of the cosmic-ray spectrum beyond 1 petaelectronvolt (PeV; 10¹⁵ electronvolts) indicates the existence of the so-called PeVatrons-cosmic-ray factories that accelerate particles to PeV energies. We need to locate and identify such objects to find the origin of Galactic cosmic rays¹. The principal signature of both electron and proton PeVatrons is ultrahigh-energy (exceeding 100 TeV) γ radiation. Evidence of the presence of a proton PeVatron has been found in the Galactic Centre, according to the detection of a hard-spectrum radiation extending to 0.04 PeV (ref. ²). Although γ-rays with energies slightly higher than 0.1 PeV have been reported from a few objects in the Galactic plane^3-6, unbiased identification and in-depth exploration of PeVatrons requires detection of γ-rays with energies well above 0.1 PeV. Here we report the detection of more than 530 photons at energies above 100 teraelectronvolts and up to 1.4 PeV from 12 ultrahigh-energy γ-ray sources with a statistical significance greater than seven standard deviations. Despite having several potential counterparts in their proximity, including pulsar wind nebulae, supernova remnants and star-forming regions, the PeVatrons responsible for the ultrahigh-energy γ-rays have not yet been firmly localized and identified (except for the Crab Nebula), leaving open the origin of these extreme accelerators.

[Primary coenzyme Q10 deficiency-7: a case report and literature review]

Objective: To explore the clinical characteristics and gene variation of primary coenzyme Q10 deficiency-7 (COQ10D7) in children. Methods: Clinical data and genetic tests results of a COQ10D7 child caused by coenzyme Q4 (COQ4) gene variation at the First Affiliated Hospital of Xiamen University in March 2020 were collected and analyzed. A literature search with "primary coenzyme Q10 deficiency" or "COQ4 gene" as the keyword was conducted at Wanfang database, China national knowledge infrastructure(CNKI), PubMed, online Mendelian inheritance in man(OMIM), ClinVar database (up to April 2020), the clinical characteristics and gene variation of children with primary COQ10D7 were summarized. Results: A 5-month-old boy was diagnosed as "epilepsy" because of intermittent epileptic seizures in three months. He had feeding difficulties, growth retardation, hypotonia of limbs and increased lactic acid. His whole exon gene testing suggested a homozygous variation of COQ4 gene (c.370G>A). One article in Chinese and 9 articles in English were found, which made up the complete case data of 33 patients (including our case). There were 12 missense variations, 2 frameshift variations, 1 splicing variation, 1 nonsense variation and 1 deletion variation, among these variations c. 370G>A was found only in children in southern China.The age of onset was mostly in the neonatal period (22 cases). Among all patients, 20 cases had presented neonatal respiratory distress or respiratory insufficiency, 21 cases had seizures, 20 cases had hypertrophic cardiomyopathy, and 26 cases had elevated serum lactic acid or lactic acidosis. Brain dysplasia, brain atrophy, basal ganglia and other lesions were observed on brain magnetic resonance imaging in 28 cases. Most of them had a poor prognosis with a mortality rate of 20/33. The age of death ranged from 4 hours to 42 months old. Conclusions: The main clinical phenotypes of primary COQ10D7 are neonatal respiratory distress or respiratory insufficiency, epilepsy, myocardial hypertrophy and lactic acid elevation. Primary COQ10D7 is caused by homozygous or compound heterozygous variation in the COQ4 gene, and c.370G>A may be the hotspot variation in children in southern China.

[Clinical characteristics and distribution of peripheral T lymphocyte subsets in patients with schistosomal hepatic diseases in Suzhou City]

OBJECTIVE

To investigate the clinical characteristics and the distribution of peripheral blood T lymphocyte sub-sets in patients with schistosomal hepatic cirrhosis in Suzhou City.

METHODS

A total of 32 inpatients with liver diseases due to advanced schistosomiasis at the Department of Infectious Diseases, The First Affiliated Hospital of Soochow University from January 2016 to January 2018 were recruited and assigned into the infection and non-infection groups according to presence of co-infections, and 20 old healthy volunteers served as controls. Venous blood samples were collected on the day of admission, and the proportions of CD4⁺ T cells, CD8⁺ T cells, regulatory T (Treg) cells and Th17 cells were detected in peripheral blood using flow cytometry.

RESULTS

Most patients with liver disorders due to advanced schistosomiasis were admitted to hospital in Suzhou City because of portal hypertension-associated complications, with a high prevalence of co-infections (59.38%, 19/32). The proportions of peripheral CD4⁺ and CD8⁺ T cells and Th17 cells were all significantly lower in patients with liver disorders due to advanced schistosomiasis than in controls (t = -5.111, -4.470 and -2.749, all P < 0.05), and a higher proportion of Treg cells was detected in patients than in controls (t = 5.628, P < 0.05). In addition, there were significant differences among the infection group, non-infection group and controls in terms of the percentage of CD4⁺ T cells, CD8⁺ T cells, Th17 cells and Treg cells (F = 15.837, 16.594, 9.290 and 27.866, all P < 0.05).

CONCLUSIONS

Portal hypertension-associated complications are predominantly seen in patients with liver diseases due to advanced schistosomiasis at admission in Suzhou City, and co-infections are common. Imbalance of peripheral T cell subsets is detected in patients with liver diseases due to advanced schistosomiasis in Suzhou City.

[Model for end-stage liver disease combined with arterial blood lactate to assess the prognosis of hepatitis B virus-associated acute-on-chronic liver failure: a retrospective analysis of 97 cases]

Objective: To explore the prognostic value of model for end-stage liver disease (MELD) combined with arterial blood lactate (Lac) in admitted patients with hepatitis B virus-associated acute- on-chronic liver failure (HBV-ACLF). Methods: Clinical data of 97 cases with hepatitis B virus-associated acute- on-chronic liver failure (HBV-ACLF) admitted to the First Affiliated Hospital of Suzhou University between March 2016 and March 2018 was retrospectively analyzed. Age, gender, complications, MELD score, lactic acid (Lac), total bilirubin (TBil), creatinine (Cr), serum albumin (Alb), high-sensitivity C-reactive protein (CRP), white blood cell count (WBC), platelet count (PLT), hematocrit (Hct), quantification of HBV DNA and HBsAg, and organ support treatment (artificial liver support system, renal replacement therapy and mechanical ventilation ) were documented after admission. The primary endpoint of treatment was death due to ineffective medical treatment during hospitalization, abandonment of medical treatment due to deterioration of the health condition, and switch to liver transplantation for patients with poor medical treatment. The risk factors for primary endpoint of treatment were analyzed by binary logistic regression. Hosmer-Lemeshow test was used to evaluate the goodness of fit for the scoring system, and the ROC to predict the prognosis of MELD-Lac. Results: Ninety-seven cases with HBV-ACLF were included, 56 cases had good prognosis, and 41 cases had bad prognosis (including two cases with poor medical treatment and liver transplantation). The overall improvement rate was 57.7%. MELD score and Lac value in treated group was significantly lower than non-treated group. Bivariable and multivariable logistic regression analysis showed that the MELD score [odds ratio (OR = 1.806)], and Lac score [odds ratio (OR = 1.820)] was the risk factor for hospitalization and mortality in patients with liver failure (P < 0.05). The area under the ROC curve (AUC) and the 95% confidence interval (95% CI) of prognostic patients with MELD-Lac were significantly better than Lac and MELD scores [0.923 (0.84 to 1.00) vs. 0.804 (0.067 to 0.942) and 0.864 (0.75). 0.977)], P < 0.05. When the MELD-Lac Youden index was set at 0.746, the optimal threshold was 18.36, and the sensitivity and specificity were 91.3% and 83.3%, respectively. Conclusion: MELD-Lac score has a high prognostic value in HBV-ACLF patients.

[A multicenter, retrospective study of pathogenic bacteria distribution and drug resistance in febrile neutropenic patients with hematological diseases in Shanghai]

目的

了解上海地区中性粒细胞缺乏（粒缺）伴发热血液病患者致病细菌的分布及耐药情况。

方法

回顾性分析2012年1月至2014年12月上海市12家医院血液科粒缺伴发热住院患者的临床分离菌株，用纸片扩散法进行药敏试验，WHONET 5.6软件分析病原菌分布及药敏数据。

结果

从上海地区粒缺伴发热患者中共分离出1 260株细菌，其中革兰阳性菌420株（33.3%），革兰阴性菌840株（66.7%）。排在前七位的分别是肺炎克雷伯菌158株（12.5%）、嗜麦芽窄食单胞菌120株（9.5%）、大肠埃希菌115株（9.1%）、铜绿假单胞菌109株（8.7%）、鲍曼不动杆菌83株（6.6%）、金黄色葡萄球菌70株（5.6%）和屎肠球菌63株（5.0%）。呼吸道分泌物标本中，非发酵菌占56.2%（350/623）。其中嗜麦芽窄食单胞菌占15.3%（95/623）。血液标本中，肠杆菌科细菌占42.3%（104/246），凝固酶阴性葡萄球菌占34.6%（85/246）。脓液标本中肠杆菌科细菌占39.4%（76/193），肠球菌属细菌占28.5%（55/193）。耐甲氧西林金黄色葡萄球菌葡萄球菌（MRSA）和耐甲氧西林凝固酶阴性葡萄球菌（MRCNS）的检出率分别为54.3%和82.5%，未发现耐利奈唑胺、万古霉素、替考拉宁葡萄球菌属菌株，耐万古霉素屎肠球菌的检出率为8.9%，肠球菌属未检出耐利奈唑胺的菌株。肠杆菌科细菌对碳青霉烯类药物高度敏感。铜绿假单胞菌对亚胺培南和美罗培南的耐药率已分别达34.1%和15.8%。嗜麦芽窄食单胞菌对米诺环素、左氧氟沙星、复方磺胺甲恶唑等药物敏感。鲍曼不动杆菌仅对头孢哌酮/舒巴坦的耐药率低于10.0%。肺炎克雷伯菌、嗜麦芽窄食单胞菌、铜绿假单胞菌、鲍曼不动杆菌等革兰阴性菌对大多常用抗菌药物的耐药率低于CHINET监测的数据。

结论

粒缺伴感染患者常见感染部位致病菌株分布有其特点，细菌耐药率整体低于CHINET全国医院大样本监测。

[The safety of decitabine as bridging pretreatment regimen before hematopoietic stem cell transplantation in pediatric hematological malignancies]

The safety of decitabine as bridging treatment before allogeneic hematopoietic stem cell transplantation (allo-HSCT) in children with refractory hematological malignancies was evaluated. All 11 cases succeeded in hematopoietic reconstitution. The main adverse reaction was hematological toxicity. Neither did infections occur, nor drug-induced liver damage and renal impairment during decitabine administration. Most cases showed grade Ⅰ-Ⅱgastrointestinal adverse events. One case was diagnosed as severe acute graft versus host disease and died of intracranial hemorrhage on day 61 after allo-HSCT. The other 10 patients survived. Decitabine bridge is a safe regimen before allo-HSCT in children with refractory hematological malignancies.

Reduced Penetrance of PRRT2 Mutation in a Chinese Family With Infantile Convulsion and Choreoathetosis Syndrome

Paroxysmal kinesigenic dyskinesia is a rare episodic movement disorder that can be isolated or associated with benign infantile seizures as part of choreoathetosis syndrome. Mutations in the PRRT2 gene have been recently identified as a cause of paroxysmal kinesigenic dyskinesia and infantile convulsion and choreoathetosis (ICCA). We reported a PRRT2 heterozygous mutation (c.604-607delTCAC, p.S202Hfs*25) in a 3-generation Chinese family with infantile convulsion and choreoathetosis and paroxysmal kinesigenic dyskinesia. The mutation was present in 5 family members, of which 4 were clinically affected and 1 was an obligate carrier with reduced penetrance of PRRT2. The affected carriers of this mutation presented with a similar type of infantile convulsion during early childhood and developed additional paroxysmal kinesigenic dyskinesia symptoms later in life. In addition, they all had a dramatic clinical response to oxcarbazepine/phenytoin therapy. Reduced penetrance of the PRRT2 mutation in this family could warrant genetic counseling.

Antisera against peptides derived from a purified mu-opioid binding protein recognize the protein as well as mu-opioid receptors in brain regions and a cell line

Two peptides, which have no significant homology with known protein structures, were obtained by microsequencing of a mu-opioid binding protein purified to homogeneity from bovine striatal membranes. Polyclonal antibodies generated against portions of these peptides immunoprecipitated up to 65% of radiolabeled purified opioid binding protein. Sequential immunoprecipitations, using antibodies directed against portions of the two different peptides, confirmed that the peptides are derived from the same protein. Immunoblots of the protein with antipeptide antibodies revealed a protein band corresponding to the molecular weight of denatured reduced mu-opioid binding protein. The immunoresponse was blocked by the appropriate peptide and was not observed with irrelevant antisera. The antipeptide antibodies were used for immunoblots of sodium dodecyl sulfate extracts of tissues from bovine brain regions and of the mu receptor-containing cell line SK-N-SH. Affinity-purified antipeptide antibody detected an immunoreactive protein of molecular weight 65,000 in brain regions containing high levels of mu-opioid receptors (striatum, thalamus, hippocampus, and frontal cortex) and in the cell line SK-N-SH. Pons, which contains low levels of receptors, produced a a barely detectable signal, whereas white matter, HeLa cells, and C6 glioma cells, devoid of opioid binding activity, produced no detectable signal. The correlation between immunoreactivity and the presence of mu-opioid binding in brain regions and cell lines and the correspondence of the molecular weight of the immunoreactive protein to that of mu-opioid receptors provide strong evidence that the peptide antisera recognize mu receptors.

Reconstitution of a purified mu-opioid binding protein in liposomes: selective, high affinity, GTP gamma S-sensitive mu-opioid agonist binding is restored

An opioid binding protein (OBP) purified to homogeneity from bovine striatal membranes has been reconstituted in liposomes. The liposomes were produced by PEG-precipitation of OBP in the presence of a CHAPS extract of bovine striatum, devoid of opioid binding. High affinity mu-agonist binding was restored. The binding was selective for mu-agonists, stereospecific and inhibited by GTP gamma S. These results demonstrate that there is recoupling of OBP with G-protein and confirm our earlier evidence that the purified OBP is a mu-opioid binding site.

Electrophilic alpha-methylene-gamma-lactone and isothiocyanate opioid ligands related to etorphine

Isothiocyanate and alpha-methylene-gamma-lactone analogues of 6,14-endo-ethenotetrahydrothebaine and -oripavine were prepared with the electrophilic groups being located at C-19 in the C-7 alpha-side chain. Isothiocyanates were prepared in the N-Me and N-CPM (N-cyclopropylmethyl) series, both as the phenols and 3-O-methyl ethers from the diastereomeric amines formed from reductive amination of thevinone (2) and N-(cyclopropylmethyl)northevinone (13). Although addition of the organozinc reagent from methyl alpha-bromomethacrylate to 25 failed, addition to 3-O-protected aldehydes 27 and 35 produced, after subsequent deprotection, alpha-methylene-gamma-lactones 29 and 37, respectively. In the opioid receptor displacement assays against [3H]bremazocine as the radiolabeled ligand, the phenolic compounds were most potent with N-CPM isothiocyanates 20 and 21 showing IC50s of 0.32 and 0.76 nM, respectively, and N-CPM alpha-methylene-gamma-lactone 37 having an IC50 = 1.0 nM. Compound 37 showed irreversible effects in the binding assay which were mu-selective, as demonstrated by analogous experiments using [3H]DAGO, and naloxone was found to protect against the irreversible effects. This observation suggests that a receptor-bound nucleophile is located at a position where it can readily reach the alpha-methylene group of lactone 37.

Cross-linking of human [125I]beta-endorphin to opioid receptors in rat striatal membranes: biochemical evidence for the existence of a mu/delta opioid receptor complex

In a modified Krebs buffer at 37 degrees C, the selective mu agonist [3H] D-Ala2,MePhe4,Gly-ol5]enkephalin [( 3H]DAMGO) and the nonselective mu/delta agonist human [125I]beta-endorphin [( 125I]beta-endH) bound to rat striatal membranes with a Kd of about 7 and 5 nM and a Bmax of about 95 and 260 fmol/mg of protein, respectively, consistent with labeling of mu receptors by the former ligand and labeling of both mu and delta receptors by the latter. The binding of 2 nM [125I]beta-endH was displaced by unlabeled DAMGO (IC50 30 nM), [D-Ala2-D-Leu5]enkephalin (IC50 60 nM) as well as by the selective delta agonists [D-Ser2(O-tert-butyl),Leu5]enkephalyl-Thr6 (DSTBULET, IC50 500 nM) and Tyr-Ala-Phe-Asp-Val-Val-Gly-NH2 (IC50 700 nM) in a monophasic manner within 2 to 3 log concentration units, suggesting an allosteric interaction between mu and delta sites labeled by [125I]beta-endH under these conditions. Accordingly, 500 nM DSTBULET caused almost 40% inhibition of the apparent Bmax without changing the apparent Kd of [3H] DAMGO. The kappa agonist U 50,488 was ineffective as competing ligand even at a concentration of 10 microM. Upon affinity cross-linking of [125I]beta-endH (2 nM) to rat striatal mu- and delta-opioid receptors, sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the solubilized tissue under reducing conditions followed by autoradiography of the dried gels revealed a major broad band of covalently labeled protein with an apparent molecular weight of 80 kDa.(ABSTRACT TRUNCATED AT 250 WORDS)

Conjugate addition ligands of opioid antagonists. Methacrylate esters and ethers of 6 alpha- and 6 beta-naltrexol

Alpha- and beta-naltrexol derived esters 9 and 10 and ethers 11 and 12, each containing the alpha, beta-unsaturated ester functionality, were prepared as conformationally more flexible analogues of spiro-alpha-methylene-gamma-lactones 5 and 6. All were active in the opioid radioreceptor binding assay against [3H]bremazocine and more active against [3H]DAGO, indicating mu-subtype selectivity, but only ether 12 showed significant irreversible activity. We conclude that small structural changes, made in very closely related electrophilic opioids, lead to changes in receptor binding. All four compounds were long-acting antagonists to morphine in mice, with ester 10 being approximately equipotent with naltrexone.