Modeling of resonantly pumped mid-infrared Pr3+-doped chalcogenide fiber amplifier with different pumping schemes

We propose a model for resonantly pumped Pr³⁺-doped chalcogenide fiber amplifiers, which includes excited state absorption and the full spectral amplified spontaneous emission spanning from 2 μm to 6 μm. Based on this model, the observed near- and mid-infrared photoluminescence generated from Pr³⁺-doped chalcogenide fiber is explained. Then the output properties of a 4.1 μm resonantly pumped Pr³⁺-doped chalcogenide fiber amplifier are simulated in both co- and counter-pumping schemes. Results show that the 4.1 μm counter-pumped fiber amplifier can achieve a power conversion efficiency (PCE) of over 62.8% for signal wavelengths ranging from 4.5 μm to 5.3 μm. This is, to our best knowledge, the highest simulated PCE for a Pr³⁺-doped chalcogenide fiber amplifier.

Heterogeneous to homogeneous melting transition visualized with ultrafast electron diffraction

The ultrafast laser excitation of matters leads to nonequilibrium states with complex solid-liquid phase-transition dynamics. We used electron diffraction at mega-electron volt energies to visualize the ultrafast melting of gold on the atomic scale length. For energy densities approaching the irreversible melting regime, we first observed heterogeneous melting on time scales of 100 to 1000 picoseconds, transitioning to homogeneous melting that occurs catastrophically within 10 to 20 picoseconds at higher energy densities. We showed evidence for the heterogeneous coexistence of solid and liquid. We determined the ion and electron temperature evolution and found superheated conditions. Our results constrain the electron-ion coupling rate, determine the Debye temperature, and reveal the melting sensitivity to nucleation seeds.

Acetylated Polyethylenimine-Entrapped Gold Nanoparticles Enable Negative Computed Tomography Imaging of Orthotopic Hepatic Carcinoma

Developing an effective computed tomography (CT) contrast agent is still a challenging task for precise diagnosis of hepatic carcinoma (HCC). Here, we present the use of acetylated polyethylenimine (PEI)-entrapped gold nanoparticles (Ac-PE-AuNPs) without antifouling modification for negative CT imaging of HCC. PEI was first linked to fluorescein isothiocyanate (FI) and then utilized as a vehicle for the entrapment of AuNPs. The particles were then acetylated to reduce its positive surface potential. The designed Ac-PE-AuNPs were characterized by various techniques. We find that the Ac-PE-AuNPs with a uniform size distribution (mean diameter = 2.3 nm) are colloidally stable and possess low toxicity in the studied range of concentration. Owing to the fact that the particles without additional antifouling modification were mainly gathered in liver, the Ac-PE-AuNPs could greatly improve the CT contrast enhancement of normal liver, whereas poor CT contrast enhancement appeared in liver necrosis region caused by HCC. As a result, HCC could be easily and precisely diagnosed. The designed Ac-PE-AuNPs were demonstrated to have biocompatibility through in vivo biodistribution and histological studies, hence holding an enormous potential to be adopted as an effective negative CT contrast agent for diagnosis of hepatoma carcinoma.

Determination of Oleandrin in Blood and Liver Samples by LC-MS/MS

OBJECTIVES

To develop a liquid chromatography-tandem mass spectrometry （LC-MS/MS） analytical method for the determination of oleandrin in blood and liver tissues, which could be applied to the cases of death caused by oleander poisoning.

METHODS

Blood or liver tissues underwent a liquid-liquid extraction （LLE） using ethyl acetate, and the extract was separated on an Agilent ZORBAX SB-C₁₈ column and eluted with a gradient of acetonitrile and 20 mmol/L ammonium acetate （containing 0.1% formic acid）. Oleandrin was detected using electrospray positive ionization （ESI+） with multiple-reaction monitoring （MRM） mode.

RESULTS

Oleandrin showed excellent linearity in both blood and liver samples in the corresponding linear range （r>0.995 0）, with detection limits 1 ng/mL and 2 ng/g, respectively, extraction recovery rates greater than 70.50%, both intra- and inter-day precisions less than 10.71%, accuracies 98.42%-111.63%, and matrix effects 91.52%-106.39%. The method was successfully applied to a case of suspected oleander poisoning. Oleandrin was detected in the blood, urine, liver tissues, bile, stomach wall tissues and stomach contents of the cadaver, with the content ranging from 65.5 to 29 600.0 ng/mL （ng/g）.

CONCLUSIONS

The method developed in this study is simple and convenient to operate with good selectivity, and is suitable for the analysis of oleandrin in biological samples such as blood and liver tissues, which can provide technical support for forensic identification and clinical diagnosis and treatment of oleander poisoning.

[Identification of New Designer Benzodiazepine Diclazepam in Drug Facilitated Sexual Assault]

OBJECTIVES

To identify the new designer drugs which are totally unknown and not in the routine testing list by the technologies such as high-resolution mass spectrometry in drug facilitated sexual assault, in order to solve the problem in actual cases.

METHODS

The milky fluid from an actual case was extracted and analyzed using LC-QE, ¹H-NMR and GC-MS, respectively. The accurate masses and cluster ions isotope patterns of unknown compound were obtained by LC-QE. The molecular formula was confirmed as C₁₆H₁₂C₂N₂O based on the protons number of ¹H-NMR. The isomers diclazepam and 4-chlorodiazepam were separated and detected with GC-MS.

RESULTS

The new designer benzodiazepine as diclazepam in the milky fluid was identified. The results provided direct evidence for the investigation and qualitative analysis of such cases.

CONCLUSIONS

The combined application of various methods, including LC-QE, ¹H-NMR and GC-MS, can be used to detect unknown new psychoactive substances.

Genome-wide association study reveals novel genes for the ear size in sheep (Ovis aries)

Variations in ear size can be observed in livestock such as sheep; however, the genetic basis of variable ear size in sheep is still poorly understood. To investigate causative genes associated with ear size in sheep, a genome-wide association study was performed in 115 adult Duolang sheep with different-sized floppy ears using the Ovine Infinium HD BeadChip. We found 38 significant SNPs at the genome-wide or chromosome-wise 5% significance level after Bonferroni correction. The most significant association (P = 1.61 × 10^-6 ) was found at SNP rs402740419, located in the DCC gene, which plays a critical role in ear development. Also, we observed two additional significant SNPs, rs407891215 in PTPRD and rs407769095 in SOX5, both of which are functionally associated with ear developmental processes. Our results are useful for future sheep breeding and provide insights into the genetic basis of ear size development in sheep and other livestock.

Electrospun PEGylated PLGA nanofibers for drug encapsulation and release

We report the fabrication of electrospun nanofibers of polyethylene glycol (PEG)-modified poly (lactic-co-glycolic acid) (PLGA) with a fast release profile for biomedical applications. In this work, PLGA was first covalently modified with methoxy poly (ethylene glycol) amine (mPEG-NH₂). The formed PEGylated PLGA (PLGA-PEG) was then mixed with a model drug amoxicillin (AMX) for subsequent fabrication of drug-loaded electrospun nanofibers. The synthesized PLGA-PEG conjugate and the formed drug-loaded PLGA-PEG nanofibers were characterized using different techniques. We show that the modification of PEG does not lead to an appreciable change in the uniform and smooth morphology of PLGA nanofibers. Importantly, the PEGylation modification affords a faster release profile of the encapsulated drug than pure PLGA nanofibers without PEGylation, which may be ascribed to the improved hydrophilicity of the PLGA-PEG polymer. Furthermore, antibacterial activity assay data reveal that the drug-loaded PLGA-PEG nanofibers are able to inhibit the growth of a model bacterium S. aureus. Finally, the hemocompatibility of the drug-loaded PLGA-PEG nanofibers was evaluated by hemolysis and anticoagulant assays, and the cytocompatibility of the fibers was confirmed by cell viability assay and cell morphology observation. We show that the formed drug-loaded PLGA-PEG nanofibers have an excellent hemocompatibility and cytocompatibility. The developed electrospun PLGA-PEG nanofibers may find various applications in the fields of tissue engineering and pharmaceutical sciences.

Radiotherapy-Sensitized Tumor Photothermal Ablation Using γ-Polyglutamic Acid Nanogels Loaded with Polypyrrole

Development of versatile nanoscale platforms for cancer diagnosis and therapy is of great importance for applications in translational medicine. In this work, we present the use of γ-polyglutamic acid (γ-PGA) nanogels (NGs) to load polypyrrole (PPy) for thermal/photoacoustic (PA) imaging and radiotherapy (RT)-sensitized tumor photothermal therapy (PTT). First, a double emulsion approach was used to prepare the cystamine dihydrochloride (Cys)-cross-linked γ-PGA NGs. Next, the cross-linked NGs served as a reactor to be filled with pyrrole monomers that were subjected to in situ oxidation polymerization in the existence of Fe(III) ions. The formed uniform PPy-loaded NGs having an average diameter of 38.9 ± 8.6 nm exhibited good water-dispersibility and colloid stability. The prominent near-infrared (NIR) absorbance feature due to the loaded PPy endowed the NGs with contrast enhancement in PA imaging. The hybrid NGs possessed excellent photothermal conversion efficiency (64.7%) and stability against laser irradiation, and could be adopted for PA imaging and PTT of cancerous cells and tumor xenografts. Importantly, we also explored the cooperative PTT and X-ray radiation-mediated RT for enhanced tumor therapy. We show that PTT of tumors can be more significantly sensitized by RT using the sequence of laser irradiation followed by X-ray radiation as compared to using the reverse sequence. Our study suggests a promising theranostic platform of hybrid NGs that may be potentially utilized for PA imaging and combination therapy of different types of tumors.

[Analysis of Arsenic Compounds in Blood and Urine by HPLC-ICP-MS]

OBJECTIVES

To establish an analysis method for the detection of 6 arsenic compounds [AsC, AsB, As（Ⅲ）, DMA, MMA and As（V）] in blood and urine by high-performance liquid chromatography-inductively coupled plasma-mass spectrometry （HPLC-ICP-MS）, and apply it to real cases.

METHODS

Triton was used to damage cells, and then EDTA·2Na·2H2O was used to complex arsenic compounds in cells, and sonication and protein deposition by acetonitrile were performed for sample pretreatment. With the mobile phase consisted of ammonium carbonate and ultrapure water, gradient elution was performed for obtaining the arsenic compounds in samples, which were analysed by ICP-MS with Hamilton PRP-X100 column.

RESULTS

The limits of detection in blood were 1.66-10 ng/mL, while the lower limits of quantitation in blood ranged from 5 to 30 ng/mL. The limits of detection in urine were 0.5-10 ng/mL, while the lower limits of quantitation in urine were 5-30 ng/mL. The relative standard deviation of inter-day and intra-day precisions was less than 10%. This method had been successfully applied to 3 cases.

CONCLUSIONS

This study has established an analysis method for detecting 6 common arsenic compounds in blood and urine, which can be used to detect the arsenic compounds in the blood and urine from arsenic poisoning cases as well as the patients under arsenic treatment.

99mTc-Labeled RGD-Polyethylenimine Conjugates with Entrapped Gold Nanoparticles in the Cavities for Dual-Mode SPECT/CT Imaging of Hepatic Carcinoma

We report the construction and characterization of ^99mTc-labeled arginine-glycine-aspartic acid (RGD)-polyethylenimine (PEI) conjugates with entrapped gold nanoparticles in the cavities (RGD-^99mTc-Au PENPs) for dual-mode single-photon emission computed tomography (SPECT)/computed tomography (CT) imaging of an orthotopic hepatic carcinoma model. In this study, PEI was successively decorated with diethylenetriaminepentaacetic acid, poly(ethylene glycol) (PEG), and PEGylated RGD segments, and was utilized as an effective nanoplatform to entrap Au NPs and to be labeled with ^99mTc. We showed that the designed RGD-^99mTc-Au PENPs displayed desirable colloidal stability and radiostability, and cytocompatibility in the investigated concentration range, and could be specifically uptaken by α_vβ₃ integrin-overexpressing liver cancer cells in vitro. In vivo CT and SPECT imaging results indicated that the particles were able to be accumulated within an orthotopic hepatic carcinoma and displayed both CT and SPECT contrast enhancement in the tumor tissue. With the proven biocompatibility in vivo via histological examinations, the designed RGD-^99mTc-Au PENPs may be potentially employed as an effective nanoprobe for a highly efficient dual-mode SPECT/CT imaging of various α_vβ₃ integrin-overexpressing tumors.

Construction of Hybrid Alginate Nanogels Loaded with Manganese Oxide Nanoparticles for Enhanced Tumor Magnetic Resonance Imaging

Development of sensitive contrast agents for positive magnetic resonance (MR) imaging of biosystems still remains a great challenge. Herein, we report a facile process to construct hybrid alginate (AG) nanogels (NGs) loaded with manganese oxide (Mn₃O₄) nanoparticles (NPs) for enhanced tumor MR imaging. The obtained AG/PEI-Mn₃O₄ NGs with a mean size of 141.6 nm display excellent colloidal stability in aqueous solution and good cytocompatibility in the studied concentration range. Moreover, the hybrid NGs have a high r₁ relaxivity of 26.12 mM^-1 s^-1, which is about 19.5 times higher than that of PEI-Mn₃O₄ NPs with PEI surface amine acetylated (PEI.Ac-Mn₃O₄ NPs). Furthermore, the AG/PEI-Mn₃O₄ NGs presented longer blood circulation time and better tumor MR imaging performances in vivo than PEI.Ac-Mn₃O₄ NPs. With the good biosafety confirmed by histological examinations, the developed AG/PEI-Mn₃O₄ NGs may be potentially used as an efficient contrast agent for enhanced MR imaging of different biosystems.

[Clinical analysis of multiple myeloma-associated amyloidosis]

Objective: To investigate the clinical features and survival of multiple myeloma-associated amyloidosis patients. Methods: Twenty three multiple myeloma-associated amyloidosis patients were retrospectively analyzed from January 2009 to December 2016. Results: The overall response rate(ORR)was 65.2% and the remission rate (sCR+ CR) was 21.7%. The median progression-free survival(PFS) was fourteen months(1-63), and the median overall survival(OS)was fifteen months(3-63). The early death rate (death rate within one year)was 33.3%. The median OS of patients(n=9)with the performance status(PS) score >2 was seven months(1-15), and the median OS of patients(n=14)with the PS score ≤2 was thirty months(10-63). There was a statistically significant difference in OS(P<0.05); the median PFS and OS of the patients (n=15) who responded to inductive treatment were seventeen months(2-63) and twenty four months (4-63)respectively, and the median PFS and OS of the patients (n=8)who did not respond to inductive treatment were three months(1-8) and eleven months (3-15) respectively. There was a statistically significant difference in PFS and OS(P<0.05). There was a statistically significant difference in PFS and OS between patients treated with remission (n=5)and those who did not(n=18) (P<0.05). Conclusions: The multiple myeloma-associated amyloidosis patients had a high early death rate and short survival time. Early identification and effective treatment are the preconditions for improving the poor prognosis.

99mTc-labelled multifunctional polyethylenimine-entrapped gold nanoparticles for dual mode SPECT and CT imaging

In this study, we report the synthesis, characterization and utilization of ^99mTc-labelled polyethylenimine-entrapped gold nanoparticles (^99mTc-Au-PENPs) for dual mode single-photon emission computed tomography/computed tomography (SPECT/CT) imaging applications. Polyethylenimine (PEI) was selected as a platform to conjugate with diethylene triamine pentacetate acid (DTPA) and polyethylene glycol monomethyl ether to synthesize Au PENPs, followed by acetylation or hydroxylation modification of the remaining PEI surface amine groups and radiolabelling of ^99mTc. The generated multifunctional ^99mTc-Au-PENPs with different surface groups (acetyl or hydroxyl) were characterized via different methods. The Au PENPs before ^99mTc labelling are colloidally stable, haemocompatibility and noncytotoxic at an Au concentration up to 100 μM. The ^99mTc-labelled Au PENPs exhibit high radiochemical purity, good stability and SPECT/CT imaging performance of different organs and lymph node. The designed strategy to use the radionuclide labelling technique and PEI-facilitated versatile nanoplatform may be extended to develop various novel nanoprobes for precision imaging applications.

[Strategy for minimally invasive cochlear implantation and residual hearing preservation]

In the past few decades, considerable development was achieved in the cochlear implantation following the emergence of innovative electrode array and advances in minimally invasive surgery. Minimally invasive technique led to a better preservation of residual low-frequency hearing. The loss of residual hearing was caused by complicated factors. According to previous studies, a slower and stable speed of electrode insertion and the use of perioperative steroids were demonstrated to have a positive impact on hearing preservation. The selection of electrode array or its insertion approaches didn't show any distinctive benefits in hearing preservation.

Construction of iron oxide nanoparticle-based hybrid platforms for tumor imaging and therapy

This review highlights the most recent progress in the construction of iron oxide nanoparticle-based hybrid platforms for tumor imaging and therapy.

Design of functional electrospun nanofibers for cancer cell capture applications

The review reports recent advances in the design of functional electrospun nanofibers for cancer cell capture applications.

A unique nanogel-based platform for enhanced dual mode tumor MR/CT imaging

Alginate nanogels loaded with gold nanoparticles and gadolinium can be synthesized via a nanoparticle-crosslinking approach for enhanced tumor MR/CT imaging.

Targeted dual-mode imaging and phototherapy of tumors using ICG-loaded multifunctional MWCNTs as a versatile platform

ICG-loaded MWCNTs can be synthesized and used as a theranostic platform for targeted dual-mode imaging and phototherapy of tumors.

[Presented with subarachnoid hemorrhage and then blood culture negative infective endocarditis: a case report and literature review]

The patient, a 43-year-old man, had paroxysmal headache three months ago, and he had complained the left occipital sharp pain, which could be alleviated by itself, with alalia and the right side of the upper limb numbness. Head computed tomography (CT) revealed a left temporal lobe intraparenchymal hemorrhage with the left side of the subarachnoid hemorrhage in small quantities. Digital subtraction angiography (DSA) revealed a suspicious aneurysm on the left internal carotid artery siphon. He had intermittent fever 1 month ago, with maximum body temperature 39 °C. He suffered headache again 20 days ago, with pain nature, duration and the way of easing up similar to the earlier onset. General examination demonstrated 2/6 grade blowing systolic murmurs at apex area. Neurological examination revealed that Babinski's sign was positive on the right side. Echocardiographic found an anterior mitral valve ve-getation on the 4th day in hospital. So his clinical diagnosis was infective endocarditis with cerebral embolism. He received vancomycin treatment immediately. His three blood cultures remained negative in hospital. His blood specimens were sent to Chinese Center for Disease Control and Prevention, indirect immunofluorescence method (IFA) IgG antibody detection revealed that the Bartonella henselae IgG antibody was positive. Therefore the clinical diagnosis was Bartonella endocarditis complicated with subarachnoid hemorrhage and cerebral embolism. Bartonella, an intracellular fastidious, gram-negative bacilli, was first documented as a cause of endocarditis in 1993 and since then has been increasingly recognized as an important etiology of infective culture-negative endocarditis. In cases of documented Bartonella endocarditis, the Infectious Diseases Society of America (IDSA) guidelines recommended 2 weeks of gentamicin plus 6 weeks of doxycycline treatment, to achieve a higher cure rate.

[Identification of Methamphetamine Abuse and Selegiline Use： Chiral Analysis of Methamphetamine and Amphetamine in Urine]

OBJECTIVES

To study the content variation of selegiline and its metabolites in urine, and based on actual cases, to explore the feasibility for the identification of methamphetamine abuse and selegiline use by chiral analysis.

METHODS

The urine samples were tested by chiral separation and LC-MS/MS method using CHIROBIOTIC™ V2 chiral liquid chromatography column. The chiral analysis of methamphetamine and amphetamine were performed on the urine samples from volunteers of selegiline use and drug addicts whom suspected taking selegiline.

RESULTS

After 5 mg oral administration, the positive test time of selegiline in urine was less than 7 h. The mass concentrations of R（-）-methamphetamine and R（-）-amphetamine in urine peaked at 7 h which were 0.86 μg/mL and 0.18 μg/mL and couldn't be detected after 80 h and 168 h, respectively. The sources of methamphetamine and amphetamine in the urine from the drug addicts whom suspected taking selegiline were analysed successfully by present method.

CONCLUSIONS

The chiral analysis of methamphetamine and amphetamine, and the determination of selegiline's metabolites can be used to distinguish methamphetamine abuse from selegiline use.

Construction of core-shell tecto dendrimers based on supramolecular host-guest assembly for enhanced gene delivery

Design of dendrimer-based nanoarchitectures for enhanced gene delivery still remains a great challenge. Here, we report the design of core-shell tecto dendrimers using a supramolecular assembly approach for enhanced gene delivery applications. Firstly, β-cyclodextrin (CD)-modified generation 5 (G5) poly(amidoamine) (PAMAM) dendrimers (G5-CD) and adamantine (Ad)-modified generation 3 (G3) PAMAM dendrimers (G3-Ad) both having amine termini were synthesized. Through the supramolecular recognition of CD and Ad, G5-CD/Ad-G3 core-shell tecto dendrimers with a G5 core and G3 shell were formed. The formed G5-CD/Ad-G3 core-shell tecto dendrimers with a size of 8.4 nm possess good monodispersity, well-defined three-dimensional structure, and quite low cytotoxicity. Importantly, with the abundant amines on the surface, the core-shell tecto dendrimers are able to transfect the luciferase (Luc) gene with an efficiency 20 times and 170 times higher than the G5-CD and G3-Ad dendrimers, respectively. The higher gene transfection efficiency can also be qualitatively confirmed by transfection of plasmid DNA encoding enhanced green fluorescence protein. Our results suggest that the developed G5-CD/Ad-G3 core-shell tecto dendrimers may be used as a promising vehicle for enhanced gene transfection applications.

Minimizing the t1-noise when using an indirect 1H high-resolution detection of unlabeled samples

The most utilized through-space correlation ¹H-{X} methods with proton indirect detection use two consecutive transfers, ¹H → X and then X → ¹H, with the evolution time t₁ in the middle. When the X isotope is not 100% naturally abundant (NA), only the signal of the protons close to these isotopes is modulated by the ¹H-X dipolar interactions. This signal is theoretically disentangled with phase-cycling from the un-modulated one. However, this separation is never perfect and it may lead to t₁-noise in case of isotopes with very small NA, such as ¹³C or even worse ¹⁵N. One way to reduce this t₁-noise is to minimize, 'purge', during t₁ the un-modulated ¹H magnetization before trying to suppress it with phase-cycling. We analyze experimentally several sequences following the HORROR condition, which allow purging the ¹H transverse magnetization. The comparison is made at three spinning speeds, including very fast ones for ¹H resolution: 27.75, 55.5 and 111 kHz. We show (i) that the efficiency of this purging process increases with the spinning speed, and (ii) that the best recoupling sequences are the two simplest ones: XY and S₁ = SR2¹₂. We then compare the S/N that can be achieved with the two most used ¹H-{X} 2D methods, called D-HMQC and CP-CP. The only difference in between these two methods is that the transfers are done with either two π/2-pulses on X channel (D-HMQC), or two Cross-Polarization (CP) transfers (CP-CP). The first method, D-HMQC, is very robust and should be preferred when indirectly detecting nuclei with high NA. The second method, CP-CP, (i) requires experimental precautions to limit the t₁-noise, and (ii) is difficult to use with quadrupolar nuclei because the two CP transfers are then not efficient nor robust. However, CP-CP is presently the best method to indirectly detect isotopes with small NA, such as ¹³C and ¹⁵N.

Optimization of the composition and dosage of PEGylated polyethylenimine-entrapped gold nanoparticles for blood pool, tumor, and lymph node CT imaging

Gold nanoparticles (Au NPs) with a high X-ray attenuation coefficient have a good potential in CT imaging applications. Here, we report the design and synthesis of Au NPs entrapped within polyethylene glycol (PEG)-modified branched polyethyleneimine (PEI) with varying the initial Au salt/PEI molar ratios and with the remaining PEI surface amines being acetylated for blood pool, lung tumor and lymph node CT imaging. The formed unacetylated and acetylated PEGylated PEI-entrapped Au NPs (Au PENPs) were characterized via different methods. We show that the PEGylated PEI is an effective template to entrap Au NPs having a uniform size ranging from 1.7nm to 4.4nm depending on the Au salt/PEI molar ratio. After optimization of the composition-dependent X-ray attenuation effect, we then selected {(Au⁰)₁₀₀-PEI·NHAc-mPEG} NPs for biological testing and show that the particles have good cytocompatibility in the given concentration range and can be used as a contrast agent for effective CT imaging of the blood pool of rats, lung cancer model of nude mice and lymph node of rabbits after intravenous injection. For each application, the injected dosage of the particles was optimized. In addition, the {(Au⁰)₁₀₀-PEI·NHAc-mPEG} NPs could be excreted out of the body with time. Our results indicate that the formed Au PENPs with an appropriate composition and dosage hold a great promise to be used for CT imaging of various biosystems.

Dendrimers meet zwitterions: development of a unique antifouling nanoplatform for enhanced blood pool, lymph node and tumor CT imaging

We report the synthesis and characterization of antifouling zwitterion carboxybetaine acrylamide (CBAA)-modified dendrimer-entrapped gold nanoparticles (Au DENPs) for enhanced CT imaging applications. The CBAA-modified nanodevice displays a better protein resistance property, less macrophage cellular uptake and liver accumulation, and longer blood half-delay time than the PEGylated counterpart material, thereby enabling enhanced blood pool, lymph node, and tumor CT imaging.

Polyaniline-loaded γ-polyglutamic acid nanogels as a platform for photoacoustic imaging-guided tumor photothermal therapy

We report the facile synthesis of polyaniline (PANI)-loaded γ-polyglutamic acid (γ-PGA) nanogels (NGs) for photoacoustic (PA) imaging-guided photothermal therapy (PTT) of tumors. In this work, γ-PGA NGs were first formed via a double emulsion approach, followed by crosslinking with cystamine dihydrochloride (Cys) via 1-ethyl-3-[3-dimethylaminopropyl]carbodiimide hydrochloride coupling chemistry. The formed γ-PGA/Cys NGs were employed as a nanoreactor to load aniline monomers via an electrostatic interaction for subsequent in situ polymerization in the presence of ammonium persulfate. The resulting γ-PGA/Cys@PANI NGs were thoroughly characterized. It is shown that the γ-PGA/Cys@PANI NGs with an average size of 71.9 nm are dispersible in water, colloidally stable, and cytocompatible and hemocompatible in the concentration range studied. The strong near-infrared (NIR) absorbance renders the NGs with good PA imaging contrast enhancement and photothermal conversion properties. With these excellent properties and biocompatibility, the developed γ-PGA/Cys@PANI NGs are able to be used for PA imaging-guided PTT of cancer cells in vitro and a xenografted tumor model in vivo. This unique theranostic nanoplatform may be further loaded with other imaging or therapeutic elements, or modified with targeting ligands, thereby providing a ubiquitous platform for multimode imaging and combinational therapy of different biosystems.

Maternal pre-gravid cardiometabolic health and infant birthweight: A prospective pre-conception cohort study

BACKGROUND AND AIMS

Both low birthweight and high birthweight have been associated with the development of cardiometabolic disease in adulthood, possibly reflecting the effect of intrauterine fetal programming. As developmental programming can begin before conception, pre-gravid factors that predict birthweight may be relevant in this context. However, little is known about such factors. Thus, we established a pre-conception cohort to identify maternal pre-gravid cardiometabolic determinants of infant birthweight.

METHODS AND RESULTS

In this prospective observational cohort study, 1484 newly-married women in Liuyang, China, underwent baseline (pre-gravid) evaluation and then were followed across a subsequent pregnancy. Pre-gravid cardiometabolic characterization consisted of clinical (anthropometry, blood pressure) and biochemical evaluation (total/LDL/HDL cholesterol, triglycerides, glucose) at median 20 weeks before a singleton pregnancy. Mean birthweight was 3294 ± 444 g, with 173 neonates large-for-gestational-age (LGA) and 110 small-for-gestational-age (SGA). On multiple linear regression analysis, positive determinants of birthweight were maternal age, pre-gravid body mass index (BMI), weight gain in pregnancy, length of gestation, and male infant (all p ≤ 0.0003). On logistic regression analysis, independent predictors of an LGA delivery were maternal age (OR = 1.10 per year, 95%CI 1.03-1.18), pre-gravid BMI (OR = 1.21 per kg/m², 1.07-1.37), and gestational weight gain (OR = 1.10 per kg, 1.06-1.14). The only independent predictor of SGA was gestational weight gain (OR = 0.93 per kg, 0.89-0.97).

CONCLUSION

Maternal weight before and during pregnancy is the predominant cardiometabolic determinant of infant birthweight, rather than pre-gravid blood pressure, glucose or lipid profile.

A genome-wide association study reveals candidate genes for the supernumerary nipple phenotype in sheep (Ovis aries)

Genome-wide association studies (GWASs) have been widely applied in livestock to identify genes associated with traits of economic interest. Here, we conducted the first GWAS of the supernumerary nipple phenotype in Wadi sheep, a native Chinese sheep breed, based on Ovine Infinium HD SNP BeadChip genotypes in a total of 144 ewes (75 cases with four teats, including two normal and two supernumerary teats, and 69 control cases with two teats). We detected 63 significant SNPs at the chromosome-wise threshold. Additionally, one candidate region (chr1: 170.723-170.734 Mb) was identified by haplotype-based association tests, with one SNP (rs413490006) surrounding functional genes BBX and CD47 on chromosome 1 being commonly identified as significant by the two mentioned analyses. Moreover, Gene Ontology enrichment for the significant SNPs identified by the GWAS analysis was functionally clustered into the categories of receptor activity and synaptic membrane. In addition, pathway mapping revealed four promising pathways (Wnt, oxytocin, MAPK and axon guidance) involved in the development of the supernumerary nipple phenotype. Our results provide novel and important insights into the genetic mechanisms underlying the phenotype of supernumerary nipples in mammals, including humans. These findings may be useful for future breeding and genetics in sheep and other livestock.

Genome-wide association analysis identifies the genetic basis of fat deposition in the tails of sheep (Ovis aries)

Fat-tailed sheep (Ovis aries) can survive in harsh environments and satisfy human's intake of dietary fat. However, the animals require more feed, which increases the cost of farming. Thus, most farmers currently prefer thin-tailed, short-tailed or docked sheep. To date, the molecular mechanism of the formation of fat tails in sheep has not been completely elucidated. Here, we conducted a genome-wide association study using phenotypes and genotypes (the Ovine Infinium HD SNP BeadChip genotype data) of two breeds of contrasting tail types (78 Small-tailed and 78 Large-tailed Han sheep breeds) to identify functional genes and variants associated with fat deposition. We identified four significantly (rs416433540, rs409848439, rs408118325 and rs402128848) and three approximately associated autosomal SNPs (rs401248376, rs402445895 and rs416201901). Gene annotation indicated that the surrounding genes (CREB1, STEAP4, CTBP1 and RIP140, also known as NRIP1) function in lipid storage or fat cell regulation. Furthermore, through an X-chromosome-wide association analysis, we detected significantly associated SNPs in the OARX: 88-89 Mb region, which could be a strong candidate genomic region for fat deposition in tails of sheep. Our results represent a new genomic resource for sheep genetics and breeding. In addition, the findings provide novel insights into genetic mechanisms of fat deposition in the tail of sheep and other mammals.

[The Role of Segmental Analysis of Clonazepam in Hair in Drug Facilitated Cases]

OBJECTIVES

To infer the frequency of dosage and medication history investigate of the victims in drug facilitated cases by the segmental analysis of clonazepam in hair.

METHODS

Freezing milling under liquid nitrogen environment combined with ultrasonic bath was used as sample pretreatment in this study, and liquid chromatography-tandem mass spectrometry was used for the segmental analysis of the hair samples collected from 6 victims in different cases. The concentrations of clonazepam and 7-aminoclonazepam were detected in each hair section.

RESULTS

Clonazepam and its metabolite 7-aminoclonazepam were detected in parts of hair sections from the 6 victims. The occurrence time of drug peak concentration was consistent with the intake timing provided by victims.

CONCLUSIONS

Segmental analysis of hair can provide the information of frequency of dosage and intake timing, which shows an unique evidential value in drug facilitated crimes.

[Evaluation of Brodifacoum-induced Toxicity by Metabonomics Approach Based on HPLC-TOF-MS]

OBJECTIVES

To analyse the metabolic changes in urine of rats with brodifacoum intoxication, and to reveal the molecular mechanism of brodifacoum-induced toxicity on rats.

METHODS

By establishing a brodifacoum poisoning rats model, the urine metabolic profiling data of rats were acquired using high performance liquid chromatography-time of flight mass spectrometry （HPLC-TOF-MS）. The orthogonal partial least squares analysis-discrimination analysis （OPLS-DA） was applied for the multivariate statistics and the discovery of differential metabolites closely related to toxicity of brodifacoum.

RESULTS

OPLS-DA score plot showed that the urinary metabolic at different time points before and after drug administration had good similarity within time period and presented clustering phenomenon. Comparing the urine samples of rats before drug administration with which after drug administration, twenty-two metabolites related to brodifacoum-induced toxicity were selected.

CONCLUSIONS

The toxic effect of brodifacoum worked by disturbing the metabolic pathways in rats such as tricarboxylic cycle, glycolysis, sphingolipid metabolism and tryptophan metabolism, and the toxicity of brodifacoum is characterized of accumulation effect. The metabonomic method based on urine HPLC-TOF-MS can provide a novel insight into the study on molecular mechanism of brodifacoum-induced toxicity.

A promising dual mode SPECT/CT imaging platform based on 99mTc-labeled multifunctional dendrimer-entrapped gold nanoparticles

Multifunctional ^99mTc-labeled dendrimer-entrapped gold nanoparticles (^99mTc-Au DENPs) were designed and synthesized. Our results show that the type of surface groups (acetyl or hydroxyl) significantly impact the biodistribution profile of the ^99mTc-Au DENPs, thereby allowing for preferential SPECT/CT imaging of different organs.

[Determination of Sulfide Ion in Blood from Hydrogen Sulfide Poisoning Cases]

OBJECTIVES

To establish a gas chromatography-mass spectrometry （GC-MS） method for the determination of sulfide ion in blood and apply it to the practical cases.

METHODS

The 1, 3, 5-tribromobenzene was selected as an internal standard, and 0.2 mL blood sample was collected and analyzed using GC-MS after α-Bromo-2, 3, 4, 5, 6-pentafluorobenzyl bromide derivatization.

RESULTS

The mass concentration of sulfide ion in blood had good linearity in the range of 0.2-40 μg/mL with a limit of detection （LOD） of 0.05 μg/mL. The mass concentration of sulfide ion was less than 0.05 μg/mL in blank blood from different sources such as healthy subjects and dead cases. In 3 sulfide poisoning cases, sulfide ion was detected in the blood samples of 6 victims, and the mass concentration range was 1.02-3.13 μg/mL.

CONCLUSIONS

This study establishes a method for investigation of sulfide ion in blood which has been applied successfully to the cases of fatal sulfide poisonings.

Genera of phytopathogenic fungi: GOPHY 1

Genera of Phytopathogenic Fungi (GOPHY) is introduced as a new series of publications in order to provide a stable platform for the taxonomy of phytopathogenic fungi. This first paper focuses on 21 genera of phytopathogenic fungi: Bipolaris, Boeremia, Calonectria, Ceratocystis, Cladosporium, Colletotrichum, Coniella, Curvularia, Monilinia, Neofabraea, Neofusicoccum, Pilidium, Pleiochaeta, Plenodomus, Protostegia, Pseudopyricularia, Puccinia, Saccharata, Thyrostroma, Venturia and Wilsonomyces. For each genus, a morphological description and information about its pathology, distribution, hosts and disease symptoms are provided. In addition, this information is linked to primary and secondary DNA barcodes of the presently accepted species, and relevant literature. Moreover, several novelties are introduced, i.e. new genera, species and combinations, and neo-, lecto- and epitypes designated to provide a stable taxonomy. This first paper includes one new genus, 26 new species, ten new combinations, and four typifications of older names.