Competition between electron doping and short-range scattering in hydrogenated bilayer graphene on hexagonal boron nitride

We studied the electron doping of bilayer graphene (BLG) on hexagonal boron nitride (h-BN) by dissociative H₂ adsorption.

Measurement of double-polarization asymmetries in the quasielastic (3)He[→](e[→],e(')d) process

We present a precise measurement of double-polarization asymmetries in the ^{3}He[over →](e[over →],e^{'}d) reaction. This particular process is a uniquely sensitive probe of hadron dynamics in ^{3}He and the structure of the underlying electromagnetic currents. The measurements have been performed in and around quasielastic kinematics at Q^{2}=0.25(GeV/c)^{2} for missing momenta up to 270  MeV/c. The asymmetries are in fair agreement with the state-of-the-art calculations in terms of their functional dependencies on p_{m} and ω, but are systematically offset. Beyond the region of the quasielastic peak, the discrepancies become even more pronounced. Thus, our measurements have been able to reveal deficiencies in the most sophisticated calculations of the three-body nuclear system, and indicate that further refinement in the treatment of their two-and/or three-body dynamics is required.

A retrospective study to assess the relative value of peripheral blood, bone marrow aspirate and biopsy morphology, immunohistochemical stains, and flow cytometric analysis in the diagnosis of chronic B cell lymphoproliferative neoplasms

INTRODUCTION

The successful diagnosis of chronic B cell lymphoproliferative neoplasms (B-CLPN) requires the integration of multiple parameters, beginning with clinical information, CBC data, and morphology review. Immunophenotyping is essential and genetic testing may also be necessary. However, the relative value of each specimen or ancillary study in the diagnosis and classification has not been systematically established. We have performed a blinded retrospective review to assess what in our laboratory was the relative value of each specimen type and ancillary study in the diagnostic workup of B-CLPN.

METHODS

A total of 185 cases of PB, BM, spleen and lymph nodes were analyzed for relative value of morphology, IHC, flow cytometry study in the diagnosis of B-CLPN.

RESULTS

'High yield' specimen was identified in most B-CLPN categories, which was highly predictive of the final WHO diagnosis.

CONCLUSION

The goal of this retrospective study was to attempt to assess what was the relative value of morphology, immunophenotype, and molecular/cytogenetic study in various sites in the overall diagnostic process in our institution. We investigated the utility of the 'high yield' specimens in achieving the correct final diagnosis. In our study, some B-CLPNs notably splenic marginal zone lymphoma and hairy cell leukemia variant, required all studies for a 'best fit' type of diagnosis. In other cases, the morphology of a single specimen type was highly predictive of the final diagnosis, although confirmatory studies are recommended for definitive diagnosis.

A 3'-UTR KRAS-variant is associated with cisplatin resistance in patients with recurrent and/or metastatic head and neck squamous cell carcinoma

BACKGROUND

A germline mutation in the 3'-untranslated region of KRAS (rs61764370, KRAS-variant: TG/GG) has previously been associated with altered patient outcome and drug resistance/sensitivity in various cancers. We examined the prognostic and predictive significance of this variant in recurrent/metastatic (R/M) head and neck squamous cell carcinoma (HNSCC).

PATIENTS AND METHODS

We conducted a retrospective study of 103 HNSCCs collected from three completed clinical trials. KRAS-variant genotyping was conducted for these samples and 8 HNSCC cell lines. p16 expression was determined in a subset of 26 oropharynx tumors by immunohistochemistry. Microarray analysis was also utilized to elucidate differentially expressed genes between KRAS-variant and non-variant tumors. Drug sensitivity in cell lines was evaluated to confirm clinical findings.

RESULTS

KRAS-variant status was determined in 95/103 (92%) of the HNSCC tumor samples and the allelic frequency of TG/GG was 32% (30/95). Three of the HNSCC cell lines (3/8) studied had the KRAS-variant. No association between KRAS-variant status and p16 expression was observed in the oropharynx subset (Fisher's exact test, P = 1.0). With respect to patient outcome, patients with the KRAS-variant had poor progression-free survival when treated with cisplatin (log-rank P = 0.002). Conversely, KRAS-variant patients appeared to experience some improvement in disease control when cetuximab was added to their platinum-based regimen (log-rank P = 0.04).

CONCLUSIONS

The TG/GG rs61764370 KRAS-variant is a potential predictive biomarker for poor platinum response in R/M HNSCC patients.

CLINICAL TRIAL REGISTRATION NUMBERS

NCT00503997, NCT00425750, NCT00003809.

Probing the repulsive core of the nucleon-nucleon interaction via the (4)He(e,e'pN) triple-coincidence reaction

We studied simultaneously the (4)He(e,e'p), (4)He(e,e'pp), and (4)He(e,e'pn) reactions at Q(2)=2(GeV/c)(2) and x(B)>1, for an (e,e'p) missing-momentum range of 400 to 830  MeV/c. The knocked-out proton was detected in coincidence with a proton or neutron recoiling almost back to back to the missing momentum, leaving the residual A=2 system at low excitation energy. These data were used to identify two-nucleon short-range correlated pairs and to deduce their isospin structure as a function of missing momentum, in a region where the nucleon-nucleon (NN) force is expected to change from predominantly tensor to repulsive. The abundance of neutron-proton pairs is reduced as the nucleon momentum increases beyond ∼500  MeV/c. The extracted fraction of proton-proton pairs is small and almost independent of the missing momentum. Our data are compared with calculations of two-nucleon momentum distributions in (4)He and discussed in the context of probing the elusive repulsive component of the NN force.

Pneumocephalus following the minimally invasive hematoma aspiration and thrombolysis for ICH

INTRODUCTION

The objective of this study was to clarify whether pneumocephalus occurred and affected the outcome following minimally invasive hematoma aspiration and thrombolysis for intracerebral hemorrhage (ICH).

MATERIALS AND METHODS

A prospective case note review on all ICH patients treated with the micro-invasive procedure presenting to our division from 2006 to 2011 was conducted. Demographic, clinical, and outcome data were documented; head CT scans were applied postoperatively to identify the intracranial air collection. The ICH victims with pneumocephalus were included into Group A and the others into Group B. A multi-variant analysis was performed between Groups A and B to examine the effect of pneumocephalus on the prognosis.

RESULTS

Data were collected on a total of 134 cases in this study, among whom 72.38% developed pneumocephalus postoperatively. No significant difference was demonstrated in terms of the preoperative and postoperative hematoma volume, Glasgow Coma Scale (GCS) score, middle line shift (MLS), and 30-day mortality rate between Groups A and B, respectively. Moreover, the long-term outcome rated by GCS of these two groups was also similar. Logistic regression analysis indicated double-needle puncture be an independent risk factor for both postoperative pneumocephalus (OR, 2.478; 95% CI, 1.010-6.080; P = 0.045) and its degree (OR, 11.84; 95%CI, 4.141-30.208; P < 0.001).

CONCLUSION

The present study shows that pneumocephalus is common following the minimally invasive hematoma aspiration and thrombolysis for ICH but may not affect the outcome. And double-needle puncture may be the risk factor for pneumocephalus.

MARCH5-mediated quality control on acetylated Mfn1 facilitates mitochondrial homeostasis and cell survival

Mitochondrial dynamics and quality control have a central role in the maintenance of cellular integrity. Mitochondrial ubiquitin ligase membrane-associated RING-CH (MARCH5) regulates mitochondrial dynamics. Here, we show that mitochondrial adaptation to stress is driven by MARCH5-dependent quality control on acetylated Mfn1. Under mitochondrial stress conditions, levels of Mfn1 were elevated twofold and depletion of Mfn1 sensitized these cells to apoptotic death. Interestingly, overexpression of Mfn1 also promoted cell death in these cells, indicating that a fine tuning of Mfn1 levels is necessary for cell survival. MARCH5 binds Mfn1 and the MARCH5-dependent Mfn1 ubiquitylation was significantly elevated under mitochondrial stress conditions along with an increase in acetylated Mfn1. The acetylation-deficient K491R mutant of Mfn1 showed weak interaction with MARCH5 as well as reduced ubiquitylation. Neither was observed in the acetylation mimetic K491Q mutant. In addition, MARCH5-knockout mouse embryonic fibroblast and MARCH5(H43W)-expressing HeLa cells lacking ubiquitin ligase activity experienced rapid cell death upon mitochondrial stress. Taken together, a fine balance of Mfn1 levels is maintained by MARCH5-mediated quality control on acetylated Mfn1, which is crucial for cell survival under mitochondria stress conditions.

Lower serum uric acid levels in cerebral amyloid angiopathy: a pilot study

Cerebral amyloid angiopathy (CAA) is a common degenerative disease presenting intracerebral hemorrhage (ICH) in older people. Uric acid (UA) is a natural antioxidant, and may have a beneficial role in neurodegenerative diseases. Nevertheless, the role of UA in CAA remains unknown. In the present study, we compared serum UA levels in CAA-associated ICH patients (n = 82) and age/sex-matched controls (n = 82). Serum UA levels in possible CAA were significantly decreased when compared with healthy controls (232.68 ± 77.70 vs. 309.42 ± 59.83 μmol/L; p < 0.001). Furthermore, UA levels in patients clinically diagnosed as probable CAA were significantly lower than those in patients diagnosed as possible CAA (193.06 ± 56.98 vs. 232.68 ± 77.70 μmol/L; p = 0.014). These differences were still significant after adjusting for renal function and dyslipidemia (p < 0.001 and p = 0.002, respectively). However, there were no associations between serum UA levels and the distribution of hemorrhagic lesion, as well as neurological impairment. Our observations indicate that serum UA levels were decreased in CAA patients. UA might play a neuroprotective role in CAA and serve as a potential biomarker for reflecting the severity of Aβ deposition.

Olea europaea Linn. Fruit Pulp Extract Protects against Carbon Tetrachloride-induced Hepatic Damage in Mice

The present study we investigated the hepatoprotective effects of Olea europaea fruit pulp extract against carbon tetrachloride-induced hepatic damage in experimental mice. Further we explored the antioxidant potential of the extract to substantiate the hepatoprotective properties. Biochemical parameters were analyzed in the serum of experimental mice using respective diagnostic kits. Antioxidant activities were measured following alkyl and hydroxyl radical scavenging assays. Compared with control groups, administration of the extract to carbon tetrachloride-treated mice significantly reduced the elevated serum levels of alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase. The carbon tetrachloride-treated morphological changes in hepatocyte architecture were also reversed by extract pretreatment. Further, the carbon tetrachloride-treated increased serum cholesterol levels such as triglyceride and low density/very low-density lipoprotein in the liver were reversed in acute and chronic carbon tetrachloride-treated mice. The extract was also found to significantly increase the serum level of high-density lipoproteins in carbon tetrachloride-treated mice. Furthermore, the extract showed significant in vitro antioxidant actions by scavenging the alkyl and hydroxyl free radicals, substantiating its use in hepatoprotection. The concentration of the extract necessary for 50% inhibition of alkyl and hydroxyl radicals was 72.41 and 52.24 μg/ml, respectively. In conclusion, data from our study suggest that Olea europaea fruit pulp extract could prevent carbon tetrachloride-treated acute and chronic liver degeneration and attenuated the lipid levels elevated by carbon tetrachloride. The hepatoprotective activity exhibited by Olea europaea extract might possibly be through its antioxidant defense mechanisms.

Hepatoprotective Effect of Houttuynia cordata Thunb Extract against Carbon Tetrachloride-induced Hepatic Damage in Mice

Houttuynia cordata Thunb (Saururaceae) is a traditional medicinal herb used to treat several disease symptoms. The present study was focused on the hepatoprotective effects of H. cordata ethyl acetate extract in experimental mice. Further the antioxidant potential of the extract was also evaluated to substantiate its hepatoprotective properties. Carbon tetrachloride-induced hepatic damage in mice was used to measure the serum biochemical parameters. Morphological changes in hepatocyte architecture were studied by haematoxylin and eosin staining. In vitro alkyl and hydroxyl free radical scavenging assays were performed to evaluate the antioxidant effect. Administration of H. cordata extract significantly reduced the elevated serum levels and regulated the altered levels of serum cholesterol in carbon tetrachloride-treated mice (P<0.05). The morphological changes in hepatocyte architecture were also reversed by H. cordata treatment. Further, the extract showed significant antioxidant actions by scavenging the alkyl and hydroxyl free radicals. The concentration of the extract necessary for 50% scavenging of alkyl and hydroxyl radicals was 15.5 and 410 μg/ml, respectively. H. cordata extract exhibited significant hepatoprotective property in carbon tetrachloride-induced hepatotoxicity in mice. The strong antioxidant activities possessed by the extract might be responsible for such actions.

Cross-sectional and dynamic change of serum metabolite profiling for Hepatitis B-related acute-on-chronic liver failure by UPLC/MS

Summary Acute-on-chronic liver failure(ACLF) is an increasingly recognized entity encompassing an acute deterioration of liver function and results in the failure of one or more organs with high short-term mortality. The focus of this study was to discover noninvasive and reliable biomarkers for the diagnosis and prognosis of hepatitis B-related ACLF. Ultra-performance liquid chromatography-mass spectrometry (UPLC/MS) was used to analyse serum metabolites of 28 patients with hepatitis B-related ACLF, 35 patients with Child-Pugh A cirrhosis, 30 patients with chronic hepatitis B and 35 healthy volunteers (HS). Characteristic metabolites were screened, identified and dynamically tracked to investigate their value for diagnosis and prognosis. After comparing serum metabolic profile of hepatitis B-related ACLF and Child-Pugh A cirrhosis, 99 characteristic metabolites were selected, and 38 of them were identified. Dynamic tracking model demonstrated that 17 metabolites were related to prognosis of hepatitis B-related ACLF, and there were also 11 metabolites which improved with treatment in the survival group. The correlations between these characteristic metabolites and the model for end-stage liver disease score were strong. These observations contributed to the investigation of the mechanisms of hepatitis B-related ACLF manifestation and progression on the metabolic level, and they provided information for the identification of biomarkers for the diagnosis and prognosis of hepatitis B-related ACLF.

Spontaneous intracerebral hemorrhage in CADASIL

BACKGROUND

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare hereditary small vascular disease and its mainly clinical manifestations are ischemic events. Spontaneous intracerebral hemorrhage (ICH) involvement in patients with CADASIL is extremely uncommon.

CASE REPORT

A 46-year-old normotensive Chinese man developed a large hematoma in the left basal ganglia after he was diagnosed with CADASIL 2 months ago, the patient did not take any antithrombotics. Susceptibility weighted imaging at pre-ICH showed multiple cerebral microbleeds (CMBs) in the bilateral basal ganglia. He experienced migraine at about 10 months post-ICH. To our knowledge, this is the first report of ICH in CADASIL patients with Arg90Cys mutation in exon 3.

DISCUSSION AND CONCLUSIONS

ICH should be considered when evaluating new attacks in CADASIL patients. Thus, MRI screening for CMBs might be helpful in predicting the risk of ICH and guiding antithrombotic therapy. In addition, strict control of hypertension and cautious use of antithrombotics may be important in this context.

Phylogenetic distinction of iNOS and IDO function in mesenchymal stem cell-mediated immunosuppression in mammalian species

Mammalian mesenchymal stem cells (MSCs) have been shown to be strongly immunosuppressive in both animal disease models and human clinical trials. We have reported that the key molecule mediating immunosuppression by MSCs is species dependent: indoleamine 2,3-dioxygenase (IDO) in human and inducible nitric oxide synthase (iNOS) in mouse. In the present study, we isolated MSCs from several mammalian species, each of a different genus, and investigated the involvement of IDO and iNOS during MSC-mediated immunosuppression. The characterization of MSCs from different species was by adherence to tissue culture plastic, morphology, specific marker expression, and differentiation potential. On the basis of the inducibility of IDO and iNOS by inflammatory cytokines in MSCs, the tested mammalian species fall into two distinct groups: IDO utilizers and iNOS utilizers. MSCs from monkey, pig, and human employ IDO to suppress immune responses, whereas MSCs from mouse, rat, rabbit, and hamster utilize iNOS. Interestingly, based on the limited number of species tested, the iNOS-utilizing species all belong to the phylogenetic clade, Glires. Although the evolutionary significance of this divergence is not known, we believe that this study provides critical guidance for choosing appropriate animal models for preclinical studies of MSCs.

Measurements of parity-violating asymmetries in electron-deuteron scattering in the nucleon resonance region

We report on parity-violating asymmetries in the nucleon resonance region measured using inclusive inelastic scattering of 5-6 GeV longitudinally polarized electrons off an unpolarized deuterium target. These results are the first parity-violating asymmetry data in the resonance region beyond the Δ(1232). They provide a verification of quark-hadron duality-the equivalence of the quark- and hadron-based pictures of the nucleon-at the (10-15)% level in this electroweak observable, which is dominated by contributions from the nucleon electroweak γZ interference structure functions. In addition, the results provide constraints on nucleon resonance models relevant for calculating background corrections to elastic parity-violating electron scattering measurements.