Intensive feeding alters the rumen microbiota and its fermentation parameters in natural grazing yaks

Introduction

Amidst the challenging environmental conditions characterized by low oxygen levels and cold temperatures on the plateau, alterations in nutrient supply emerge as pivotal factors influencing the survival and reproduction of yaks. Intensive feeding stands out as a substantial mechanism for nutrient provision, initiating discernible changes in the host's rumen flora. Within the extreme natural conditions prevailing in the plateau area of northwest Yunnan, China, there exists a con-strained comprehension of the variations in rumen microflora, fermentation parameters, and growth responses exhibited by yaks subjected to intensive feeding.

Methods

This study employs 16S rRNA and ITS sequencing methods to scrutinize the rumen flora of yaks engaged in both natural grazing (G) and intensive feeding (F) on the plateau.

Results

The outcomes unveil that, during the severe winter season, yaks adeptly modulate the abundance and diversity of rumen flora in response to dietary modifications under intensive feeding, aiming to optimize the efficient utilization of dietary fiber and energy. Principal Coordinate Analysis (PCoA) illustrates a substantial alteration in the rumen microbial community of naturally grazing yaks when exposed to intensive feeding. The natural grazing group manifests a higher prevalence of Firmicutes and Bacteroidetes, while the intensive feeding group exhibits heightened levels of Prevotella in the rumen. The Rikenellaceae _ RC9 _ gut_ group, associated with mycobacteria, prevails more abundantly in the natural grazing setting. PICRUSt2 analysis indicates that intensive feeding induces bacterial gene overexpression linked to protein metabolism. Rumen fungi showcase heightened diversity under intensification. Intensive feeding results in an augmented abundance of non-fiber-degrading bacteria and semi-fiber-degrading bacteria, accompanied by elevated concentrations of Volatile Fatty Acids (VFA).

Discussion

These findings yield novel insights into the shifts in the rumen microflora of yaks acclimated to intensive feeding in high-altitude environments, provide an important reference for the nutritional regulation of supplemental feeding of natural grazing yaks in the cold season, ultimately contributing to their enhanced growth.

Acceleration and transport of relativistic electrons in the jets of the microquasar SS 433

SS 433 is a microquasar, a stellar binary system that launches collimated relativistic jets. We observed SS 433 in gamma rays using the High Energy Stereoscopic System (H.E.S.S.) and found an energy-dependent shift in the apparent position of the gamma-ray emission from the parsec-scale jets. These observations trace the energetic electron population and indicate that inverse Compton scattering is the emission mechanism of the gamma rays. Our modeling of the energy-dependent gamma-ray morphology constrains the location of particle acceleration and requires an abrupt deceleration of the jet flow. We infer the presence of shocks on either side of the binary system, at distances of 25 to 30 parsecs, and that self-collimation of the precessing jets forms the shocks, which then efficiently accelerate electrons.

A Novel Planning and Delivery Technology: Dose, Dose Rate and Linear Energy Transfer (LET) Optimization Based on Spot-Scanning Proton Arc Therapy FLASH (SPLASHLET)

PURPOSE/OBJECTIVE(S)

To achieve a high conformal dose with Linear Energy Transfer (LET) optimized FLASH proton therapy, we introduced a new planning and delivery technique concept, the voxel-wised optimization of LET distribution and dose rate based on scanning arc therapy (SPLASHLET) MATERIALS/METHODS: The algorithm optimizes (1) the clinical dose-volume constraint based on dose distribution and (2) the clinical LET-volume constraint based on LET distribution using Alternating Direction Method of Multipliers (ADMM) with Limited-memory BFGS solver by minimizing the monitor unit (MU) constraint on spot weight and (3) the effective dose-average dose rate by minimizing the accelerator's beam current sequentially. Such optimization framework enables the high dose conformal dynamic arc therapy with the capability of LET painting with voxel-based FLASH dose rate in an open-source proton planning platform (MatRad, Department of Medical Physics in Radiation Oncology, German Cancer Research Center-DKFZ). It aiming to minimize the overall cost function value combined with plan quality and voxel-based LET and dose rate constraints. Three representative cases (brain, liver and prostate cancer) were used for testing purposes. Dose-volume histogram (DVH), LET volume histogram (LVH) dose rate volume histogram (DRVH) and dose rate map were assessed compared to the original SPArc plan (SPArcoriginal).

RESULTS

SPLASHLET plan could offer comparable plan quality compared to SPArcoriginal plan. The DRVH results indicated that SPArcoriginal could not achieve FLASH using the clinic beam current configuration, while SPLASHLET could significantly not only improve V40Gy/s in target and region of interest (ROI) but also improve the mean LET in the target and reduce the high LET in organ at risk (OAR) in comparison with SPArcoriginal (Table 1).

CONCLUSION

SPLASHLET offers the first LET painting with voxel-based ultra-dose-rate and high-dose conformity treatment using proton beam therapy. Such technique has the potential to take full vantage of LET painting, FLASH and SPArc.

Van der Waals isotope heterostructures for engineering phonon polariton dispersions

Element isotopes are characterized by distinct atomic masses and nuclear spins, which can significantly influence material properties. Notably, however, isotopes in natural materials are homogenously distributed in space. Here, we propose a method to configure material properties by repositioning isotopes in engineered van der Waals (vdW) isotopic heterostructures. We showcase the properties of hexagonal boron nitride (hBN) isotopic heterostructures in engineering confined photon-lattice waves-hyperbolic phonon polaritons. By varying the composition, stacking order, and thicknesses of h10BN and h11BN building blocks, hyperbolic phonon polaritons can be engineered into a variety of energy-momentum dispersions. These confined and tailored polaritons are promising for various nanophotonic and thermal functionalities. Due to the universality and importance of isotopes, our vdW isotope heterostructuring method can be applied to engineer the properties of a broad range of materials.

Clinimetric properties of relevant criteria for assessing writing and drawing orientation after right hemisphere stroke

BACKGROUND

Writing and drawing orientation is rarely assessed in clinical routine, although it might have a potential value in detecting impaired verticality perception after right hemispheric stroke (RHS). Assessment tools and criteria must be conceived and validated. We therefore explored the clinimetric properties of a set of quantitative writing and drawing orientation criteria, their ranges of normality, and their tilt prevalence in RHS individuals.

NEW METHODS

We asked 69 individuals with subacute RHS and 64 matched healthy controls to write three lines and to copy the Gainotti Figure (house and trees). We determined six criteria referring to the orientation of writing and drawing main axes: for writing, the line and margin orientations, and for drawing, the tree, groundline, wall, and roofline orientations. Orientations were measured by using an electronic protractor from specific landmarks positioned by independent evaluators.

RESULTS

The set of criteria fulfilling all clinimetric properties (feasibility, measurability, reliability) comprised the line orientation of the writing and the wall and roofline orientations of the drawing. Writing and drawing tilts were frequent after RHS (about 30% by criterion).

COMPARISON WITH EXISTING METHODS

So far, graphomotor orientation was mostly tested qualitatively and could not be objectively appreciated in absence of validated tools and criteria, and without ranges of normality. Writing and drawing tilts may now be assessed both in routine clinical practice and research.

CONCLUSIONS

Our study paves the way for investigating the clinical determinants of graphomotor tilts, including impaired verticality perception, to better understand their underlying mechanisms.

A repeating fast radio burst associated with a persistent radio source

The dispersive sweep of fast radio bursts (FRBs) has been used to probe the ionized baryon content of the intergalactic medium1, which is assumed to dominate the total extragalactic dispersion. Although the host-galaxy contributions to the dispersion measure appear to be small for most FRBs2, in at least one case there is evidence for an extreme magneto-ionic local environment3,4 and a compact persistent radio source5. Here we report the detection and localization of the repeating FRB 20190520B, which is co-located with a compact, persistent radio source and associated with a dwarf host galaxy of high specific-star-formation rate at a redshift of 0.241 ± 0.001. The estimated host-galaxy dispersion measure of approximately [Formula: see text] parsecs per cubic centimetre, which is nearly an order of magnitude higher than the average of FRB host galaxies2,6, far exceeds the dispersion-measure contribution of the intergalactic medium. Caution is thus warranted in inferring redshifts for FRBs without accurate host-galaxy identifications.

Clinical insights into cisplatin-induced arrhythmia in a patient with locally advanced non-small cell lung cancer: a case report

OBJECTIVE

Cardiotoxicity is a common adverse effect of many antineoplastic agents, including anthracyclines and paclitaxel. However, it has not been defined as a causal side effect of cisplatin. Here we report on a patient with locally advanced non-small cell lung cancer who developed a cardiotoxic event induced by cisplatin that manifested primarily as arrhythmia.

MATERIALS AND METHODS

Intensive cardiac monitoring through electrocardiogram was performed to estimate the severity degree and clinical condition of arrhythmia.

RESULTS

The frequency and severity of the arrhythmia had a strong temporal relationship with the administration of cisplatin, that made it likely that cisplatin was responsible for the cardiotoxicity observed.

CONCLUSIONS

In the present case report, we discuss the potential factors that may provide pivotal contributions to the patient's susceptibility to cardiotoxicity and review the published studies regarding the cardiotoxic influence of cisplatin. We also outline the critical points that oncologists should be aware of when dealing with such high-risk patients.

A bimodal burst energy distribution of a repeating fast radio burst source

The event rate, energy distribution and time-domain behaviour of repeating fast radio bursts (FRBs) contain essential information regarding their physical nature and central engine, which are as yet unknown^1,2. As the first precisely localized source, FRB 121102 (refs. ^3-5) has been extensively observed and shows non-Poisson clustering of bursts over time and a power-law energy distribution^6-8. However, the extent of the energy distribution towards the fainter end was not known. Here we report the detection of 1,652 independent bursts with a peak burst rate of 122 h^-1, in 59.5 hours spanning 47 days. A peak in the isotropic equivalent energy distribution is found to be approximately 4.8 × 10³⁷ erg at 1.25 GHz, below which the detection of bursts is suppressed. The burst energy distribution is bimodal, and well characterized by a combination of a log-normal function and a generalized Cauchy function. The large number of bursts in hour-long spans allows sensitive periodicity searches between 1 ms and 1,000 s. The non-detection of any periodicity or quasi-periodicity poses challenges for models involving a single rotating compact object. The high burst rate also implies that FRBs must be generated with a high radiative efficiency, disfavouring emission mechanisms with large energy requirements or contrived triggering conditions.

Dynamics of Emim+ in [Emim][TFSI]/LiTFSI Solutions as Bulk and under Confinement in a Quasi-liquid Solid Electrolyte

Quasi-liquid solid electrolytes are a promising alternative for next-generation Li batteries. These systems combine the safety of solid electrolytes with the desired properties of liquids and are typically formed by solutions of Li salts in ionic liquids incorporated into solid matrices. Here, we present a fundamental understanding of the transport properties in solutions of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) in 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Emim][TFSI]), either in bulk form or incorporated in a boron nitride (BN) matrix. We performed a series of quasi-elastic neutron scattering experiments that, given the high incoherent neutron scattering cross section of hydrogen, allowed us to focus on the Emim⁺ dynamics. First, [Emim][TFSI]/LiTFSI solutions (0.5 and 2.5 mol·kg^-1) were investigated and we show how the increase in the concentration reduces the Emim⁺ mobility and increases the activation energy of their long-range motions. Then, the 0.5 mol·kg^-1 solution was incorporated into the BN matrix and we report that the diffusivities of the Emim⁺ cations that remain mobile under confinement are highly accelerated in comparison with the bulk sample and the activation energy of these motions is drastically reduced. We present the experimental evidence that this effect is related to the content of the Emim⁺ cations immobilized near the surfaces of the BN pores.

Beneficial effects of endophytic Pantoea ananatis with ability to promote rice growth under saline stress

AIMS

Soil salinization severely inhibits plant growth, leading to a low crop yield. The aim of the current study was to isolate endophytic bacteria with the ability to promote rice growth under saline conditions.

METHODS AND RESULTS

We isolated eight salt-tolerant endophytic bacteria from rice roots. An isolated strain D1 was selected due to its ability to stimulate rice seed germination in the presence of NaCl, which was identified as Pantoea ananatis D1. It exhibited multiple plant growth-promoting traits including phosphate solubilization, production of indole-3-acetic acid, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase and siderophore. Inoculation of P. ananatis D1 obviously enhanced the rice root and shoot growth under normal and saline conditions. It also significantly increased the contents of chlorophyll, total soluble protein, and proline in salt-stressed rice seedlings. Moreover P. ananatis D1 could ameliorate the oxidative stress in rice induced by NaCl and Na₂ CO₃ treatment. The malondialdehyde content and various antioxidant enzyme activities were decreased by P. ananatis D1 inoculation in salt-affected rice. In addition, P. ananatis D1 showed a positive potential for limiting the Na⁺ accumulation and enhancing the K⁺ uptake, leading to an increase of 1·2-1·7 fold in K⁺ /Na⁺ ratio under saline environment.

CONCLUSIONS

Pantoea ananatis D1 has the ability to improve the salt tolerance of rice seedlings.

SIGNIFICANCE AND IMPACT OF THE STUDY

The application of plant growth-promoting bacteria (PGPB) is an eco-friendly strategy to improve plant tolerance towards abiotic stresses. We demonstrated that P. ananatis D1 could be used as an effective halotolerant PGPB to enhance rice growth in different salt-affected soils.

[Imaging analysis of respiratory epithelial adenomatoid hamartoma in the nasal olfactory clefts]

Objective:To analyze the imaging features of respiratory epithelial adenomatoid hamartoma (REAH) in the nasal olfactory clefts. Method:Forty-two patients with REAH in the nasal olfactory clefts confirmed by pathology were enrolled in this study and their imaging features were analyzed. Result:All lesions of the patients were located in bilateral olfactory clefts, accompanied by varying degrees of sinusitis and nasal polyps. CT and MRI of sinuses showed that expanded soft tissue in bilateral olfactory region. The bilateral middle turbinate was extruded laterally. Sagittal images showed "discoid-shaped mass" changes. Conclusion:The imaging manifestations of REAH have certain characteristics, which can provide a basis for clinical diagnosis. Clinical analysis combined with imaging examination can improve the diagnosis of REAH and guide the treatment.

Notch3 signaling activation in smooth muscle cells promotes extrauterine growth restriction-induced pulmonary hypertension

BACKGROUND AND AIMS

Early postnatal life is a critical developmental period that affects health of the whole life. Extrauterine growth restriction (EUGR) causes cardiovascular development problems and diseases, including pulmonary arterial hypertension (PAH). PAH is characterized by proliferation, migration, and anti-apoptosis of pulmonary artery smooth muscle cells (PASMCs). However, the role of PASMCs in EUGR has not been studied. Thus, we hypothesized that PASMCs dysfunction played a role in EUGR-induced pulmonary hypertension.

METHODS AND RESULTS

Here we identified that postnatal nutritional restriction-induced EUGR rats exhibited an elevated mean pulmonary arterial pressure and vascular remodeling at 12 weeks old. PASMCs of EUGR rats showed increased cell proliferation and migration features. In EUGR-induced PAH rats, Notch3 signaling was activated. Relative mRNA and protein expression levels of Notch3 intracellular domain (Notch3 ICD), and Notch target gene Hey1 in PASMCs were upregulated. We further demonstrated that pharmacological inhibition of Notch3 activity by using a γ-secretase inhibitor DAPT, which blocked the cleavage of Notch proteins to ICD peptides, could effectively inhibit PASMC proliferation. Specifically knocked down of Notch3 in rat PASMCs by shRNA restored the abnormal PASMC phenotype in vitro. We found that administration of Notch signaling inhibitor DAPT could successfully reduce mean pulmonary arterial pressure in EUGR rats.

CONCLUSIONS

The present study demonstrated that upregulation of Notch3 signaling in PASMCs was crucial for the development of EUGR-induced PAH. Blocking Notch3-Hey1 signaling pathway in PASMCs provides a potential therapeutic target for PAH.

Simplified colonic dialysis with hemodialysis solutions delays the progression of chronic kidney disease

BACKGROUND

The colon plays a vital role in the disposal of nitrogenous waste products. Therefore, the colon may provide a therapeutic target for managing chronic kidney disease (CKD).

AIM

To evaluate the efficacy of a simplified model of colonic dialysis with hemodialysis solutions (SCD) to delay the progression of stages 3-5 CKD.

DESIGN

Retrospective study.

METHODS

We retrospectively analyzed 178 stages 3-5 CKD patients who did or did not receive SCD (SCD group, n = 88; control group, n = 90). The follow-up was 36 months. The outcome of CKD progression was defined as a decrease in 50% or more in estimated glomerular filtration rate, starting hemodialysis or peritoneal dialysis or undergoing transplantation. The Kaplan-Meier analysis was used to compare CKD progression between SCD and control groups as well as between subgroups at different CKD stages. Cox proportional hazard models adjusted for patients' characteristics were used to examine the association between SCD and the outcome.

RESULTS

For all patients, the outcome was significantly better in SCD group compared to control group (P < 0.05). The results were similar in the subgroups of patients at stage 4 (P = 0.001) and stage 5 (P = 0.000), but not in the subgroup of patients at stage 3 (P = 0.121). For all patients, SCD was associated with a lower risk of CKD progression after adjusted for patients' characteristics (adjusted hazard ratio, 0.373; 95% confidence interval, 0.201-0.694; P 0.002).

CONCLUSION

SCD is an effective supplementary therapy to delay the progression of stages 4-5 CKD.

[The application of 3D reconstruction in investigating the frontal sinus drainage pathway based on computer tomography data]

Objective:The aim of this study is to explore the value of 3D reconstruction technology based on computer tomography data in understanding the frontal sinus drainage pathway. Method:Three-dimensional reconstruction of DICOM data from 100 cases of sinus CT was performed by using Mimics 19.0 software. The 3D models were used to study types, the relative locations of frontal sinus and recess cells as well as the influence of the frontal sinus drainage pathway. Result:The 3D model of frontal sinus, frontal recess cells and frontal sinus drainage pathway were reconstructed successfully. Among them, the incidence of nasal cavity was 95.5% (191/200), nasal cavity was 31.5% (63/200), nasal cavity on the frontal air room was 24.5% (49/200) supra bulla cells were 54% (108/200), supra bulla frontal cells were 14.5% (29/200), supraorbital ethmoid cells were 20.5% (41/200), and the rate of frontal septal cells were 4% (8/200). It visually demonstrated the relationship between the frontal recess and the frontal sinus drainage channel. Conclusion:The 3D reconstruction technology based on computer tomography data not only helps us to understand the anatomy of the frontal sinus, the relative position of the frontal crypt and the effect on the frontal sinus drainage channel, but also provides a new method for preoperative planning and intraoperative guidance to endoscopic frontal sinus surgery.

Predictors of long-term neurological outcomes in non-accidental head injury

BackgroundNon-accidental head injury (NAI) is an inflicted injury usually on a child, often resulting in long-term neurological impairment and occasionally death. This study aimed to investigate the predictive values of acute findings, especially ocular, for long-term neurological outcomes.MethodsMedical records including retinal images of all children who attended the local Children's hospital with a diagnosis of NAI from over a period of 5 years were reviewed and data collected via the electronic patient record system. Patient demographics, injuries sustained, wide-field digital retinal images, visual acuity and sequalae, neurological function, and global function was noted. IBM SPSS software program was used for statistical analysis.ResultsOf the 38 patients (24 males, 14 females), 12 children died acutely from the head injury with the remaining 26 children available for long-term follow-up. A younger age of injury (P=0.004) was the only statistically significant predictor of good neurological outcome as compared with absence of macular retinoschisis, unilateral retinal haemorrhage, and unilateral subdural haemorrhage. Of the 38 children, 17 children had retinoschisis; 9 children with macular retinoschisis died acutely while 4 suffered a degree of developmental delay and only 4 were developmentally normal at the last follow-up. Long-term visual acuity data was available for 18 of the 26 survivors (range: NPL to Snellen 6/5). A statistical significance was noted between retinoschisis and worsened visual acuity (P<0.05).ConclusionsBilateral macular retinoschisis on acute presentation of NAI is associated with a seven-fold and unilateral with a four-fold increase in the development of a poor neurological outcome and eventual death. Conflicting to other studies, younger children presented better neurological outcomes.

Imaging the Localized Plasmon Resonance Modes in Graphene Nanoribbons

We report a nanoinfrared (IR) imaging study of the localized plasmon resonance modes of graphene nanoribbons (GNRs) using a scattering-type scanning near-field optical microscope (s-SNOM). By comparing the imaging data of GNRs that are aligned parallel and perpendicular to the in-plane component of the excitation laser field, we observed symmetric and asymmetric plasmonic interference fringes, respectively. Theoretical analysis indicates that the asymmetric fringes are formed due to the interplay between the localized surface plasmon resonance (SPR) mode excited by the GNRs and the propagative surface plasmon polariton (SPP) mode launched by the s-SNOM tip. With rigorous simulations, we reproduce the observed fringe patterns and address quantitatively the role of the s-SNOM tip on both the SPR and SPP modes. Furthermore, we have seen real-space signatures of both the dipole and higher-order SPR modes by varying the ribbon width.

Identification of translationally controlled tumor protein in promotion of DNA homologous recombination repair in cancer cells by affinity proteomics

Translationally controlled tumor protein(TCTP) has been implicated in the regulation of apoptosis, DNA repair and drug resistance. However, the underlying molecular mechanisms are poorly defined. To better understand the molecular mechanisms underlying TCTP involved in cellular processes, we performed an affinity purification-based proteomic profiling to identify proteins interacting with TCTP in human cervical cancer HeLa cells. We found that a group of proteins involved in DNA repair are enriched in the potential TCTP interactome. Silencing TCTP by short hairpin RNA in breast carcinoma MCF-7 cells leads to the declined repair efficiency for DNA double-strand breaks on the GFP-Pem1 reporter gene by homologous recombination, the persistent activation and the prolonged retention of γH2AX and Rad51 foci following ionizing radiation. Reciprocal immunoprecipitations indicated that TCTP forms complexes with Rad51 in vivo, and the stability maintenance of Rad51 requires TCTP in MCF-7 cells under normal cell culture conditions. Moreover, inactivation of TCTP by sertraline treatment enhances UVC irradiation-induced apoptosis in MCF-7 cells, and causes sensitization to DNA-damaging drug etoposide and DNA repair inhibitor olaparib. Thus, we have identified an important role of TCTP in promoting DNA double-stand break repair via facilitating DNA homologous recombination processes and highlighted the great potential of TCTP as a drug target to enhance conventional chemotherapy for cancer patients with high levels of TCTP expression.

An international comparison of retinopathy of prematurity grading performance within the Benefits of Oxygen Saturation Targeting II trials

Purpose

To investigate whether the observed international differences in retinopathy of prematurity (ROP) treatment rates within the Benefits of Oxygen Saturation Targeting (BOOST) II trials might have been caused by international variation in ROP disease grading.

Methods

Groups of BOOST II trial ophthalmologists in UK, Australia, and New Zealand (ANZ), and an international reference group (INT) used a web based system to grade a selection of RetCam images of ROP acquired during the BOOST II UK trial. Rates of decisions to treat, plus disease grading, ROP stage grading, ROP zone grading, inter-observer variation within groups and intra-observer variation within groups were measured.

Results

Forty-two eye examinations were graded. UK ophthalmologists diagnosed treat-requiring ROP more frequently than ANZ ophthalmologists, 13.9 (3.49) compared to 9.4 (4.46) eye examinations, P=0.038. UK ophthalmologists diagnosed plus disease more frequently than ANZ ophthalmologists, 14.1 (6.23) compared to 8.5 (3.24) eye examinations, P=0.021. ANZ ophthalmologists diagnosed stage 2 ROP more frequently than UK ophthalmologists, 20.2 (5.8) compared to 12.7 (7.1) eye examinations, P=0.026. There were no other significant differences in the grading of ROP stage or zone. Inter-observer variation was higher within the UK group than within the ANZ group. Intra-observer variation was low in both groups.

Conclusions

We have found evidence of international variation in the diagnosis of treatment-requiring ROP. Improved standardisation of the diagnosis of treatment-requiring ROP is required. Measures might include improved training in the grading of ROP, using an international approach, and further development of ROP image analysis software.

High non-esterified fatty acid concentrations promote expression and secretion of fibroblast growth factor 21 in calf hepatocytes cultured in vitro

Negative energy balance is considered as the pathological basis of energy metabolic disorders in periparturient dairy cows. Serum non-esterified fatty acids (NEFA) are one of the most important indicators of energy balance status. Fibroblast growth factor 21 (FGF21) has been identified as a hepatokine involved in regulation of metabolic adaptations, such as promoting hepatic lipid oxidation and ketogenesis, during energy deprivation. However, the direct effects of NEFA on FGF21 expression and secretion in bovine hepatocytes are not entirely clear. The objective of this study was to investigate the effects of different NEFA concentrations on FGF21 expression and secretion in calf hepatocytes cultured in vitro. NEFA were added to the culture solution at final concentrations of 0.6, 1.2, 1.8 and 2.4 mmol/L. After 24 hr of continuous culture, FGF21 mRNA and protein expression levels in the hepatocytes were determined by real-time PCR and Western blot respectively. FGF21 secretion in the supernatant was determined by enzyme-linked immunosorbent assay (ELISA). The results showed that expression and secretion of FGF21 at 0.6 mmol/L NEFA-treated hepatocytes was higher than that of the control group (p < .05). The FGF21 expression and secretion were similar at 1.2, 1.8 and 2.4 mmol/L NEFA-treated hepatocytes and significantly higher than those observed for controls (p < .01). These data suggest that high concentrations of NEFA significantly promote FGF21 expression and secretion in bovine hepatocytes. In particular, this promotion occurs in a dose-dependent manner and may be involved in the pathological processes of energy metabolism disorders of dairy cows in the peripartum period.

Ultraconfined Plasmonic Hotspots Inside Graphene Nanobubbles

We report on a nanoinfrared (IR) imaging study of ultraconfined plasmonic hotspots inside graphene nanobubbles formed in graphene/hexagonal boron nitride (hBN) heterostructures. The volume of these plasmonic hotspots is more than one-million-times smaller than what could be achieved by free-space IR photons, and their real-space distributions are controlled by the sizes and shapes of the nanobubbles. Theoretical analysis indicates that the observed plasmonic hotspots are formed due to a significant increase of the local plasmon wavelength in the nanobubble regions. Such an increase is attributed to the high sensitivity of graphene plasmons to its dielectric environment. Our work presents a novel scheme for plasmonic hotspot formation and sheds light on future applications of graphene nanobubbles for plasmon-enhanced IR spectroscopy.

Novel poly (ADP-ribose) polymerase inhibitor, AZD2281, enhances radiosensitivity of both normoxic and hypoxic esophageal squamous cancer cells

Radiotherapy plays an important role in the treatment of esophageal squamous cell carcinoma (ESCC). However, the outcome of radiotherapy in ESCC remains unsatisfactory because esophageal squamous cancer cells, particularly those under hypoxic condition, exhibit radioresistance. The aim of this study was to determine whether or not AZD2281, a potent poly (ADP-ribose) polymerase (PARP) inhibitor, could enhance the radiation sensitivity of two ESCC cell lines, namely ECA109 and TE13. The radiosensitizing effect of AZD2281 was evaluated on the basis of cell death, clonogenic survival and tumor xenograft progression. AZD2281 alone was slightly toxic to ESCC cell lines. Apoptosis was increased and clonogenic survival was decreased in both cell lines when AZD2281 was combined with ionizing radiation (IR) under normoxic condition. AZD2281 enhanced IR-induced apoptosis to a more significant level under chronic hypoxic condition (0.2% O(2), 48 hour) than under normoxic condition. AZD2281 also slightly enhanced clonogenic cell death under chronic hypoxic condition compared with that under normoxic condition. This result could be associated with increased radiation-induced DNA double-strand breaks (DSB), decreased DSB repair and increased apoptosis of ESCC cells. Furthermore, homologous recombination (HR) protein Rad51 expression and focus formation were decreased in ESCC cells exposed to moderate chronic hypoxic condition (0.2% O(2), 48 hour); this result indicated that chronic hypoxic ESCC cells were HR deficient, possibly causing contextual synthetic lethality with PARP inhibitor in radiation sensitization. AZD2281 was also a radiation sensitizer in ESCC tumor xenograft models. Hence, in vitro and in vivo findings provide evidence that AZD2281 potently sensitizes ESCC cells to X-ray irradiation. The selective cell killing of HR-defective hypoxic cells contributes to radiosensitization by PARP inhibitor in ESCC cells under hypoxic condition.

A report on emergent uranyl binding phenomena by an amidoxime phosphonic acid co-polymer

XAFS investigations of uranyl binding by an adsorbent polymer reveal different coordination modes than anticipated from previous small molecule studies.

A mechanistic study on tumour spheroid formation in thermosensitive hydrogels: experiments and mathematical modelling

Thermo-reversible microgels to culture and harvest uniform-sized tumour spheroids with a narrow size-distribution.

Edge and Surface Plasmons in Graphene Nanoribbons

We report on nano-infrared (IR) imaging studies of confined plasmon modes inside patterned graphene nanoribbons (GNRs) fabricated with high-quality chemical-vapor-deposited (CVD) graphene on Al2O3 substrates. The confined geometry of these ribbons leads to distinct mode patterns and strong field enhancement, both of which evolve systematically with the ribbon width. In addition, spectroscopic nanoimaging in the mid-infrared range 850-1450 cm(-1) allowed us to evaluate the effect of the substrate phonons on the plasmon damping. Furthermore, we observed edge plasmons: peculiar one-dimensional modes propagating strictly along the edges of our patterned graphene nanostructures.

Tunneling Plasmonics in Bilayer Graphene

We report experimental signatures of plasmonic effects due to electron tunneling between adjacent graphene layers. At subnanometer separation, such layers can form either a strongly coupled bilayer graphene with a Bernal stacking or a weakly coupled double-layer graphene with a random stacking order. Effects due to interlayer tunneling dominate in the former case but are negligible in the latter. We found through infrared nanoimaging that bilayer graphene supports plasmons with a higher degree of confinement compared to single- and double-layer graphene, a direct consequence of interlayer tunneling. Moreover, we were able to shut off plasmons in bilayer graphene through gating within a wide voltage range. Theoretical modeling indicates that such a plasmon-off region is directly linked to a gapped insulating state of bilayer graphene, yet another implication of interlayer tunneling. Our work uncovers essential plasmonic properties in bilayer graphene and suggests a possibility to achieve novel plasmonic functionalities in graphene few-layers.

Clinicopathological and phenotypic features of chronic NK cell lymphocytosis identified among patients with asymptomatic lymphocytosis

INTRODUCTION

Chronic natural killer (NK) cell lymphocytosis is currently a provisional entity. This study demonstrated NK cell lymphocytosis in patients with asymptomatic lymphocytosis and presented the hematological and phenotypic findings.

METHODS

Flow cytometry analysis was performed for investigation of unexplained peripheral lymphocytosis. NK cells were determined by the phenotype of CD3-/CD16+/CD56+. Chronic NK cell lymphocytosis was defined by a NK cell count of ≥ 2 × 10(9)/L, persistent for over 6 months, no evidence of B- or T-cell clonality and no hematologic disorders.

RESULTS

Among 190 patients with peripheral lymphocytosis, 15(7.9%) patients, age 42-72 years, were identified to have NK cell lymphocytosis, with a median NK cell count of 3.1 × 10(9)/L (range 2.1-7.3 × 10(9)/L). Persistent NK cell lymphocytosis was confirmed with a median follow-up of 18 months. CD56(bright) NK cell populations were seen in eight patients and CD56(dim) NK cells in seven patients. CD57 co-expression was seen in both CD56(dim) and CD56(bright) cells. CD7, CD2, or CD8 expression was seen in some of the NK populations. The NK cell lymphocytosis appeared stable and no progression to NK cell leukemia during the follow-up period.

CONCLUSION

This study demonstrated that chronic NK cell lymphocytosis, similar to monoclonal B lymphocytosis or T-cell clones, may account for asymptomatic lymphocytosis. There were no identifiable causes of the NK cell expansion. The variable phenotype may represent the heterogeneity and pathological features of NK lymphocytosis.

Graphene on hexagonal boron nitride as a tunable hyperbolic metamaterial

Hexagonal boron nitride (h-BN) is a natural hyperbolic material, in which the dielectric constants are the same in the basal plane (ε(t) ≡ ε(x) = ε(y)) but have opposite signs (ε(t)ε(z) < 0) in the normal plane (ε(z)). Owing to this property, finite-thickness slabs of h-BN act as multimode waveguides for the propagation of hyperbolic phonon polaritons--collective modes that originate from the coupling between photons and electric dipoles in phonons. However, control of these hyperbolic phonon polaritons modes has remained challenging, mostly because their electrodynamic properties are dictated by the crystal lattice of h-BN. Here we show, by direct nano-infrared imaging, that these hyperbolic polaritons can be effectively modulated in a van der Waals heterostructure composed of monolayer graphene on h-BN. Tunability originates from the hybridization of surface plasmon polaritons in graphene with hyperbolic phonon polaritons in h-BN, so that the eigenmodes of the graphene/h-BN heterostructure are hyperbolic plasmon-phonon polaritons. The hyperbolic plasmon-phonon polaritons in graphene/h-BN suffer little from ohmic losses, making their propagation length 1.5-2.0 times greater than that of hyperbolic phonon polaritons in h-BN. The hyperbolic plasmon-phonon polaritons possess the combined virtues of surface plasmon polaritons in graphene and hyperbolic phonon polaritons in h-BN. Therefore, graphene/h-BN can be classified as an electromagnetic metamaterial as the resulting properties of these devices are not present in its constituent elements alone.

Subdiffractional focusing and guiding of polaritonic rays in a natural hyperbolic material

Uniaxial materials whose axial and tangential permittivities have opposite signs are referred to as indefinite or hyperbolic media. In such materials, light propagation is unusual leading to novel and often non-intuitive optical phenomena. Here we report infrared nano-imaging experiments demonstrating that crystals of hexagonal boron nitride, a natural mid-infrared hyperbolic material, can act as a ‘hyper-focusing lens' and as a multi-mode waveguide. The lensing is manifested by subdiffractional focusing of phonon–polaritons launched by metallic disks underneath the hexagonal boron nitride crystal. The waveguiding is revealed through the modal analysis of the periodic patterns observed around such launchers and near the sample edges. Our work opens new opportunities for anisotropic layered insulators in infrared nanophotonics complementing and potentially surpassing concurrent artificial hyperbolic materials with lower losses and higher optical localization.

Hexagonal boron nitride has many interesting properties, including a natural hyperbolic dispersion, making it attractive for nanophotonic applications. Here, Dai et al. show that metallic disks under the material launch phonon–polaritons, turning it into a hyper-focusing lens.