Metagenomics as New Tool for Diagnosis of Scrub Typhus: Two Case Reports.

Scrub typhus is a vector-borne infectious disease caused by Orientia tsutsugamushi. Accurate and timely diagnosis at the early infection stage could save the patients' lives. Traditional technologies were limited to rapidly and successfully detecting Orientia tsutsugamushi due to poor specificity, especially in the condition of atypical symptoms. The technology of Metagenomic next-generation sequencing (mNGS) is amenable to finding the real pathogen because it holds potential as a diagnostic platform for unbiased pathogen identification and precision medicine. Herein, we reported two clinical case reports relative to the Orientia tsutsugamushi infection diagnosed by mNGS. We hope these two cases will improve clinical diagnosis.

Late Oligocene fossil acorns and nuts of Quercus section Cyclobalanopsis from the Nanning Basin, Guangxi, South China.

Quercus is the largest genus within the Fagaceae and has a rich fossil record. Most of the fossil material is attributed to the subgenus Quercus based on leaves, pollen or rarely acorns and nuts. Fossil records of Q. section Cyclobalanopsis characterized by ring-cupped acorns are relatively few and especially those described based on nuts are scant. In this study, we described four new species of Quercus section Cyclobalanopsis based on mummified acorns and nuts: Q. paleodisciformis X.Y. Liu et J.H. Jin sp. nov., Q. paleohui X.Y. Liu et J.H. Jin sp. nov., Q. nanningensis X.Y. Liu et J.H. Jin sp. nov. and Q. yongningensis X.Y. Liu et J.H. Jin sp. nov. These species closely resemble the extant species Q. disciformis, Q. hui, Q. kerrii, and Q. dinghuensis. The occurrence of Q. section Cyclobalanopsis in the Oligocene stratum of Guangxi, South China, suggests that the section has diversified within its extant distribution center since the Oligocene. By combining records from other areas, we propose that the section first appeared in the middle Eocene of East Asia (Sino-Japan), has diversified in situ with a few elements scattering into West Asia and southern Europe since the Oligocene and Pliocene, respectively, and finally became restricted in East Asia since the Pleistocene. This indicates that the section originated and diversified in East Asia, before spreading into West Asia no later than the Oligocene and into southern Europe by the Pliocene. Subsequently it disappeared from South Europe and West Asia due to the appearance of the (summer dry) Mediterranean climate and widespread cooling during the Pleistocene.

Fabrication of Silicon Nanowires by Metal-Assisted Chemical Etching Combined with Micro-Vibration.

In this work, we design a micro-vibration platform, which combined with the traditional metal-assisted chemical etching (MaCE) to etch silicon nanowires (SiNWs). The etching mechanism of SiNWs, including in the mass-transport (MT) and charge-transport (CT) processes, was explored through the characterization of SiNW's length as a function of MaCE combined with micro-vibration conditions, such as vibration amplitude and frequency. The scanning electron microscope (SEM) experimental results indicated that the etching rate would be continuously improved with an increase in amplitude and reached its maximum at 4 µm. Further increasing amplitude reduced the etching rate and affected the morphology of the SiNWs. Adjusting the vibration frequency would result in a maximum etching rate at a frequency of 20 Hz, and increasing the frequency will not help to improve the etching effects.

Cryptocarya chinensis from the Upper Pleistocene of South China and its biogeographic and paleoecological implications.

Anatomical structure of mummified wood of Cryptocarya (Lauraceae) from the Upper Pleistocene of Maoming, South China and the woods of 15 extant species of Cryptocarya from China and Malaysia were examined. The fossil wood has been convincingly attributed to extant species Cryptocarya chinensis (Hance) Hemsl. This is the first reliable fossil record of Cryptocarya in Asia. The finding combined with the results of Biomod2 species distribution modeling suggest that the range of C. chinensis in the Late Pleistocene in South China and North Vietnam was very restricted due to increased continental aridity and enhanced temperature seasonality in this region. Thus, modern populations of C. chinensis in Maoming can be considered as glacial relicts. The mines (larval tunnels) produced by the larvae of flies from the genus Phytobia Lioy (Agromyzidae, Diptera) were observed in fossil wood under study. These cambial miners have never been reported in Cryptocarya.

Glacial expansion of cold-tolerant species in low latitudes: megafossil evidence and species distribution modelling.

Fossil wood of Chinese white pine (Pinus armandii Franch.) from the Late Pleistocene deposits of Maoming Basin of South China provides the first megafossil evidence for glacial expansion of the range of a cold-tolerant species in low latitudes.

Left Atrial Anterior Wall Scar-Related Atrial Tachycardia in Patients after Catheter Ablation or Cardiac Surgery: Electrophysiological Characteristics and Ablation Strategy.

Background: The mechanisms of atrial tachycardia (AT) related to the left atrial anterior wall (LAAW) are complex and can be challenging to map in patients after catheter ablation for atrial fibrillation (AF) or cardiac surgery. We aimed to investigate the electrophysiological characteristics AT and to devise an ablation strategy. Methods and Results: We identified 31 scar-related LAAW reentrant ATs in 22 patients after catheter ablation for AF or cardiac surgery. Activation maps of the left atrium (LA) or both atria were obtained using a high-density mapping system, and the precise mechanism and critical area for each AT were analyzed. Patients were followed up regularly in a clinic. After analyzing the activation and propagation of each AT, the scar-related LAAW ATs were classified into three types, based on mechanisms related to: (1) LAAW conduction gap(s) in 19 LA macro-reentrant ATs; (2) LAAW epicardial connection(s) in 11 LA or bi-atrial ATs; and (3) LAAW local micro-reentry in 1 LAAW AT. Multiple ATs were identified in seven patients. Effective ablation (termination or circuit change of AT) was obtained in 30 ATs by targeting the critical area identified by the mapping system. During 16.0 ± 7.6 months follow-up, recurrent AT occurred in two patients. Conclusions: Three mechanisms of scar-related AT of LAAW were identified, most of which were related to LAAW conduction gaps. Notably, epicardial AT or bi-atrial AT comprised a nonnegligible proportion. A high-density mapping system could make it possible to determine the accurate mechanism of AT and serve as a guide following ablation.

Genomic and Transcriptomic Analysis of Neuroendocrine Transformation in ALK-Rearranged Lung Adenocarcinoma After Treatments With Sequential ALK Inhibitors: A Brief Report.

Introduction: Neuroendocrine (NE) transformation has been reported in patients with ALK-rearranged NSCLC after ALK inhibition, but unlike EGFR-mutant NSCLC, the exact mechanism of NE transformation in ALK-rearranged NSCLC is poorly studied. Methods: We collected the matched pre- and post-transformation samples from a patient with ALK-rearranged lung adenocarcinoma (LUAD) and performed targeted panel sequencing, whole exome sequencing, and bulk RNA sequencing. Results: Multiple mutations were shared between the pretransformation and post-transformation samples. Neither RB1 nor TP53 mutation was detected, but CDKN2A deletion and CDK4 amplification were found instead. Mismatch repair-associated mutational signature was significantly enriched after transformation. Genes associated with Notch signaling and PI3K/AKT pathway were significantly up-regulated, whereas genes related to lymphocyte activation and NF-kB signaling were down-regulated. Signatures relating to homologous recombination, mismatch repair, and Notch signaling pathways were enriched, which were further validated in The Cancer Genome Atlas cohorts. Macrophages M2 were found to have prominently higher abundance in the tumor immune microenvironment after NE transformation. Conclusions: The mechanism of NE transformation in ALK-rearranged LUAD may be different from that in EGFR-mutant LUAD.

Therapeutic targeting RORγ with natural product N-hydroxyapiosporamide for small cell lung cancer by reprogramming neuroendocrine fate.

Small cell lung cancer (SCLC) is an aggressive and exceptionally fatal disease. Unlike non- small cell lung cancer (NSCLC), no targetable genetic driver events have been identified in SCLC to date. Here, we investigate the function of RAR-related orphan receptor gamma (RORγ) and identified the anti-cancer activity of its natural inhibitor against SCLC and illustrate the underlying mechanism. We show that RORγ depletion affected cell growth both in 2-D cell proliferation and 3-D organoids formation. Natural marine product N-hydroxyapiosporamide (N-hydap) directly bound to RORγ and inhibited its transcriptional activity, leading to the blocking of transmission process of RORγ signaling. Gene expression profiling analysis revealed that N-hydap reprograms neuroendocrine fate via inhibiting RORγ activity in SCLC. Chromatin immunoprecipitation analysis showed that N-hydap strongly reduced RORγ occupancy and transcriptional activation-linked histone marks H3K27ac on the promoter and/or enhancer sites of neurogenesis markers gene including aurora kinase a (AURKA), delta like canonical Notch ligand 3 (DLL3) and tubulin beta 3 class III (TUBB3). Therapeutically, N-hydap exhibited a strong inhibitory effect on tumor growth and did not show significant toxicity in SCLC mice xenograft models. Taken together, RORγ could be an attractive target for SCLC and thus N-hydap can be a promising therapeutic drug candidate for SCLC by inhibiting the RORγ activation.

Lighting up hydrogen peroxide in living cells by a novel quinoxalinamine based fluorescent probe.

Hydrogen peroxide (H2O2), a member of small-molecule reactive oxygen species (ROS), plays vital roles in normal physiological activities and the occurrence of many diseases. In this work, two off-on fluorescent probes, QX8A-H2O2 and QX9A-H2O2, were firstly designed for H2O2 detection with novel fused quinoxalines as the fluorophores and boronate moiety as the reaction sites. By comparing the optical properties, QX9A-H2O2 with better performance was selected for further studies. QX9A-H2O2 exhibited a high sensitivity to H2O2 with the detection limit as low as 46 nM, and displayed a good selectivity towards H2O2 over other reactants such as ROS, biothiols and various ions. The detection was based on the intramolecular charge transfer (ICT), proceeding through a sequential oxidative hydrolysis, 1,6-rearrangement elimination and decarboxylation process to release the fluorophore QX9A. Moreover, probe QX9A-H2O2 was cell permeable and was successfully employed in both exogenous and endogenous H2O2 imaging in living cells.

High expression of eIF4A2 is associated with a poor prognosis in esophageal squamous cell carcinoma.

Eukaryotic initiation factor 4A-II (eIF4A2) is an ATP-dependent RNA helicase involved in mRNA translation. Abnormal expression of eIF4A2 has been reported as a prognostic factor in different types of cancer. However, little is known regarding the function of eIF4A2 in esophageal squamous cell carcinoma (ESCC). In the present study, 253 samples were collected from patients diagnosed with ESCC, and the expression of eIF4A2 was detected by immunohistochemical staining. The clinicopathological and prognostic significance of eIF4A2 expression in ESCC were then statistically analyzed. The results demonstrated that eIF4A2 was specifically localized to the cytoplasm. Kaplan-Meier analysis also revealed that eIF4A2 expression was associated with the clinical prognosis of patients with ESCC. The median disease-free and overall survival times were 40 and 48 months for patients with low eIF4A2 expression, compared with 16 and 25 months in the high eIF4A2 expression group, respectively. In conclusion, high expression levels of eIF4A2 are associated with a poor prognosis and may be used as a potential prognostic indicator in patients with ESCC.

A single-loop macroreentrant biatrial flutter identified by the Rhythmia mapping system.

We herein present a rare case of perimitral annulus (MA) counterclockwise single-loop macro-reentrant biatrial flutter utilizing Bachmann's bundle (BB), the atrial septum and the coronary sinus (CS) ostium as the critical components of the reentrant circuit, even though the left atrial anterior line was blocked. By acknowledging the interatrial conduction via the BB and the CS identified by the ultrahigh-resolution mapping result, we could understand the atrial flutter mechanism and successfully treat the patient.

A rare case of pseudomyogenic hemangioendothelioma (PHE)/epithelioid sarcoma-like hemangioendothelioma (ES-H) of the breast first misdiagnosed as metaplastic carcinoma by FNAB and review of the literature.

AIMS: Pseudomyogenic hemangioendothelioma (PHE)/epithelioid sarcoma-like hemangioendothelioma (ES-H) is a rare vascular tumor of intermediate malignancy that commonly occurs in soft tissue of distal extremities of young adults. PHE typically has a multifocal presentation and can involve several tissue planes, including the dermis, subcutis, muscle and bone. METHODS AND RESULTS: We present here a unique case of PHE/ESH that arose in the breast as well as a review of the published literature. The initial biopsy was interpreted as a metaplastic carcinoma. However, complete resection largely revealed plump epithelioid cells, and a more spindled cell component was also noted. The cells displayed abundant eosinophilic cytoplasm and central vesicular nuclei arranged in loose fascicles, with a mild, mixed acute and chronic inflammatory infiltrate. Overall, linear membranous staining of CD31 and lack of CD34 expression were highly suggestive of PHE. At the same time, FOSB immunoreactivity was observed, which supported PHE/ESH instead of metaplastic carcinoma. The patient has not shown recurrence in the half year follow up after total mastectomy. CONCLUSION: To our knowledge, this is the first report of breast involvement in this neoplasm. Recognition of its histopathological features and immunohistochemical reactivity will prevent misdiagnosis of breast lesions.

Effects of DDIT4 in Methamphetamine-Induced Autophagy and Apoptosis in Dopaminergic Neurons.

Methamphetamine (METH) is an illicit psychoactive drug that can cause a variety of detrimental effects to the nervous system, especially dopaminergic pathways. We hypothesized that DNA damage-inducible transcript 4 (DDIT4) is involved in METH-induced dopaminergic neuronal autophagy and apoptosis. To test the hypothesis, we determined changes of DDIT4 protein expression and the level of autophagy in rat catecholaminergic PC12 cells and human dopaminergic SH-SY5Y cells, and in the hippocampus, prefrontal cortex, and striatum of Sprague Dawley rats exposed to METH. We also examined the effects of silencing DDIT4 expression on METH-induced dopaminergic neuronal autophagy using fluorescence microscopy and electron microscopy. Flow cytometry and Western blot were used to determine apoptosis and the expression of apoptotic markers (cleaved caspase-3 and cleaved PARP) after blocking DDIT4 expression in PC12 cells and SH-SY5Y cells with synthetic siRNA, as well as in the striatum of rats by injecting LV-shDDIT4 lentivirus using a stereotaxic positioning system. Our results showed that METH exposure increased DDIT4 expression that was accompanied with increased autophagy and apoptosis in PC12 cells (3 mM) and SH-SY5Y cells (2 mM), and in the hippocampus, prefrontal cortex, and striatum of rats. Inhibition of DDIT4 expression reduced METH-induced autophagy and apoptosis in vitro and in vivo. However, DDIT4-related effects were not observed at a low concentration of METH (1 µM). These results suggest that DDIT4 plays an essential role in METH-induced dopaminergic neuronal autophagy and apoptosis at higher doses and may be a potential gene target for therapeutics in high-dose METH-induced neurotoxicity.

Caspase-11 plays an essential role in methamphetamine-induced dopaminergic neuron apoptosis.

Methamphetamine (METH) is an extremely addictive stimulant drug that is widely used with high potential of abuse. Previous studies have shown that METH exposure damages the nervous system, especially dopaminergic neurons. However, the exact molecular mechanisms of METH-induced neurotoxicity remain unclear. We hypothesized that caspase-11 is involved in METH-induced neuronal apoptosis. We tested our hypothesis by examining the change of caspase-11 protein expression in dopaminergic neurons (PC12 and SH-SY5Y) and in the midbrain of rats exposed to METH with Western blotting. We also determined the effects of blocking caspase-11 expression with wedelolactone (a specific inhibitor of caspase-11) or siRNA on METH-induced apoptosis in PC12 cells and SH-SY5Y cells using Annexin V and TUNEL staining. Furthermore, we observed the protein expression changes of the apoptotic markers, cleaved caspase-3 and cleaved poly(ADP-ribose) polymerase 1 (PARP), after silencing the caspase-11 expression in rat midbrain by injecting LV-shcasp11 lentivirus using a stereotaxic positioning system. Results showed that METH exposure increased caspase-11 expression both in vitro and in vivo, with the effects in vitro being dose- and time-dependent. Inhibition of caspase-11 expression with either wedelolactone or siRNAs reduced the number of METH-induced apoptotic cells. In addition, blocking caspase-11 expression inhibited METH-induced activation of caspase-3 and PARP in vitro and in vivo, suggesting that caspase-11/caspase-3 signal pathway is involved in METH-induced neurotoxicity. These results indicate that caspase-11 plays an essential role in METH-induced neuronal apoptosis and may be a potential gene target for therapeutics in METH-caused neurotoxicity.

S-Nitrosylating protein disulphide isomerase mediates α-synuclein aggregation caused by methamphetamine exposure in PC12 cells.

Methamphetamine (METH) belongs to Amphetamine-type stimulants, METH abusers are at high risk of neurodegenerative disorders, including Parkinson's disease (PD). However, there are still no effective treatments to METH-induced neurodegeneration because its mechanism remains unknown. In order to investigate METH's neurotoxic mechanism, we established an in vitro PD pathology model by exposing PC12 cells to METH. We found the expression of nitric oxide synthase (NOS), nitric oxide (NO) and α-synuclein (α-syn) was significantly increased after METH treatment for 24h, in addition, the aggregattion of α-syn and the S-nitrosylation of protein disulphideisomerase(PDI) were also obviously enhanced. When we exposed PC12 cells to the NOS inhibitor N-nitro-L-arginine(L-NNA) with METH together, the L-NNA obviously inhibited these changes induced by METH. While when we exposed PC12 cells to the precursor of NO L-Arginine together with METH, the L-Arginine resulted in the opposite effect compared to L-NNA. And when we knocked down the PDI gene, the L-NNA did not have this effect. Therefore, PDI plays a significant role in neurological disorders related to α-syn aggregation, and it suggests that PDI could be as a potential target to prevent METH-induced neurodegeneration.

Inhibition of ROCK2 expression protects against methamphetamine-induced neurotoxicity in PC12 cells.

Methamphetamine is a type of psychoactive drug. It is well known that neurotoxicity caused by Methamphetamine(METH) can damage the nervous system and lead to apoptosis and cell loss of dopaminergic neurons. ROCK2 is a prominent target for gene therapy because its inhibition has proved to have a protective effect in various cell lines and pathophysiological conditions. Although several of the negative effects of METH on the dopaminergic system have been studied, the protective molecular mechanisms and the effective treatment of METH-induced apoptosis remain to be clarified. We hypothesized that ROCK2 is involved in METH-induced apoptosis. We tested our hypothesis using RT-PCR and western blotting to analyze whether silencing of ROCK2 with small interfering RNA (siROCK2) could reduce damage and apoptosis in PC12 cells after METH exposure. Increases in viability and cytomorphological changes were detected by MTT assay and bright field microscopy after pretreatment of METH-treated PC12 cells with 100 nM siROCK2. Apoptosis decreased significantly after ROCK2 silencing, as shown by Annexin V and TUNEL staining. The results show that ROCK2 is a possible gene target for therapeutics in METH-induced neurotoxicity in vitro, providing a foundation for future in vivo research.