Liver Transplantation in a Woman with Mahvash Disease.

Mahvash disease is an exceedingly rare genetic disorder of glucagon signaling characterized by hyperglucagonemia, hyperaminoacidemia, and pancreatic α-cell hyperplasia. Although there is no known definitive treatment, octreotide has been used to decrease systemic glucagon levels. We describe a woman who presented to our medical center after three episodes of small-volume hematemesis. She was found to have hyperglucagonemia and pancreatic hypertrophy with genetically confirmed Mahvash disease and also had evidence of portal hypertension (recurrent portosystemic encephalopathy and variceal hemorrhage) in the absence of cirrhosis. These findings established a diagnosis of portosinusoidal vascular disease, a presinusoidal type of portal hypertension previously known as noncirrhotic portal hypertension. Liver transplantation was followed by normalization of serum glucagon and ammonia levels, reversal of pancreatic hypertrophy, and resolution of recurrent encephalopathy and bleeding varices.

Analysis of full and empty ratio of EV71 virus by using capillary zone electrophoresis.

Hand, foot, and mouth disease is a serious public health problem, and the main pathogen is enterovirus 71 (EV71). Its capsid assembly mechanism including capsid protein processing has been widely studied. Full and empty capsids have different immunological efficacy. Therefore, tracking full/empty capsid ratio throughout the EV71 production process is important to ensure consistent product quality and proper dosing response. The analysis of full/empty capsid ratio of intact virus has been widely reported as well. A variety of techniques have been employed to evaluate the full/empty capsid ratios. However, there has not been a rapid, reproducible, and robust assay to determine the full/empty capsid ratios of final and in-process products. In this study, a novel assay based on capillary zone electrophoresis was established. The separation of full and empty species could be achieved within 10 min and the ratio of peak areas was used to calculate the full/empty capsid ratio directly. The results showed good reproducibility and linearity for the determination of full/empty capsid ratios.

Bending-induced enhanced spatial separation of dopants and long-lived conventional nanoribbon p-n junctions.

The spatial separation of dopants is crucial in extending the lifetime of nanoribbon p-n junctions, which is traditionally realized via van der Waals heterostructures at a high cost. In this study, we employ atomistic quantum mechanical simulations to demonstrate that a simple in-plane bending deformation can lead to an enhanced doping preference in conventional nanoribbons. Dopants with larger atomic sizes than those of host atoms tend to reside on the tensile side close to the outermost edge of the bent nanoribbons, while dopants with smaller atomic sizes than those of host atoms tend to reside on the compressive side close to the innermost edge of the bent nanoribbons. We also show that this doping preference induces an enhanced spatial separation of n-type and p-type dopants with different atomic sizes. As conventional nanoribbons are easier to synthesize and cost-effective, our results provide a pathway for modulating dopant distribution and designing long-lived nanoribbon p-n junctions via inhomogeneous strain engineering.

Origins of the short circuit current of a current mismatched multijunction photovoltaic cell considering subcell reverse breakdown.

In the photovoltaic community, short circuit current (Isc) of a current mismatched multijunction photovoltaic (MJPV) cell was usually thought to be limited by the lowest subcell photocurrent (Imin). However, under certain conditions for multijunction solar cells, Isc≠Imin was observed by researchers, while this effect has not been studied in multijunction laser power converters (MJLPCs). In this work, we provide an in-depth analysis of the formation mechanisms for the Isc of the MJPV cell by measuring I-V curves of the GaAs and InGaAs LPCs with different number of subcells and simulating the I-V curves with the reverse breakdown of each subcell considered. It is found that Isc of an N-junction PV cell can be theoretically equal to any current value within a range from a current lower than Imin to the maximum subcell photocurrent, which is up to the number of subcell current steps in the forward biased I-V curve. An MJPV cell with a constant Imin will demonstrate a higher Isc if it has more subcells, smaller subcell reverse breakdown voltage and smaller series resistance. As a result, Isc tends to be limited by the photocurrent of a subcell closer to the middle cell and is less sensitive to the optical wavelength than Imin. This should be another possible reason why the measured EQE of a multijunction LPC exhibits a wider spectrum width than the calculated Imin-based EQE, whereas this was usually attributed to the luminescent coupling effect merely.

Negative Design Margin Realization through Deep Path Activity Detection Combined with Dynamic Voltage Scaling in a 55 nm Near-Threshold 32-Bit Microcontroller.

This paper presents an innovative approach for predicting timing errors tailored to near-/sub-threshold operations, addressing the energy-efficient requirements of digital circuits in applications, such as IoT devices and wearables. The method involves assessing deep path activity within an adjustable window prior to the root clock's rising edge. By dynamically adapting the prediction window and supply voltage based on error detection outcomes, the approach effectively mitigates false predictions-an essential concern in low-voltage prediction techniques. The efficacy of this strategy is demonstrated through its implementation in a near-/sub-threshold 32-bit microprocessor system. The approach incurs only a modest 6.84% area overhead attributed to well-engineered lightweight design methodologies. Furthermore, with the integration of clock gating, the system functions seamlessly across a voltage range of 0.4 V-1.2 V (5-100 MHz), effectively catering to adaptive energy efficiency. Empirical results highlight the potential of the proposed strategy, achieving a significant 46.95% energy reduction at the Minimum Energy Point (MEP, 15 MHz) compared to signoff margins. Additionally, a 19.75% energy decrease is observed compared to the zero-margin operation, demonstrating successful realization of negative margins.

Comparison of Preoperative Alpha-blockade for Resection of Paraganglioma and Pheochromocytoma.

OBJECTIVE: Phenoxybenzamine (nonselective, noncompetitive alpha-blocker) is the preferred drug for preoperative treatment of pheochromocytoma, but doxazosin (selective, competitive alpha-blocker) may be equally effective. We compared the efficacy of doxazosin vs phenoxybenzamine. METHODS: We conducted a prospective study of patients undergoing pheochromocytoma or paraganglioma resection by randomizing pretreatment with phenoxybenzamine or doxazosin at a single tertiary referral center. The high cost of phenoxybenzamine led to high crossover to doxazosin. Randomization was halted, and a consecutive historical cohort of phenoxybenzamine patients was included for a case-control study design. The efficacy of alpha-blockade was assessed with preinduction infusion of incremental doses of phenylephrine. The primary outcomes were mortality, cardiovascular complications, and intensive care unit admission. The secondary outcomes were hemodynamic instability index (proportion of operation outside of hemodynamic goals), adequacy of blockade by the phenylephrine titration test, and drug costs. RESULTS: Twenty-four patients were prospectively enrolled (doxazosin, n = 20; phenoxybenzamine, n = 4), and 15 historical patients treated with phenoxybenzamine were added (total phenoxybenzamine, n = 19). No major cardiovascular complications occurred in either group. The phenylephrine dose-response curves showed less blood pressure rise in the phenoxybenzamine than in the doxazosin group (linear regression coefficient = 0.008 vs 0.018, P = .01), suggesting better alpha-blockade in the phenoxybenzamine group. The median hemodynamic instability index was 14% vs 13% in the phenoxybenzamine and doxazosin groups, respectively (P = .56). The median highest daily cost of phenoxybenzamine was $442.20 compared to $5.06 for doxazosin. CONCLUSION: Phenoxybenzamine may blunt intraoperative hypertension better than doxazosin, but this difference did not translate to fewer cardiovascular complications and is offset by a considerably increased cost.

Therapeutic effects and perspective of stem cell extracellular vesicles in aging and cancer.

Senescent cells can secrete a plethora of cytokines which induce senescent phenotype of neighboring cells and was called senescence-associated secretory phenotype. Previously, it was believed that cancer was caused by the infinite division and uncontrolled proliferation of cells. Based on this, anticancer treatments were all aimed at killing cancer cells. Cancer is now considered an age-related disease. Cancer cells are not exogenous, but one of the worst results of injuries which initially induce cell senescence. Therefore, reversing cell senescence can fundamentally prevent and treat cancer. Though current anticancer treatments induce the cancer cells apoptosis, they induce senescence of normal cells at the same time, thus promoting the occurrence and development of cancer and forming a vicious circle. Extracellular vesicles (EVs) are nano-sized vesicles which partially mirror their parent cells. In the tumor microenvironment, EVs of senescent cells can change the expression profile of cancer cells, contributing to their resistance to chemotherapy. There is growing evidence indicates that stem cell EVs exert effective antiaging and anticancer actions by transferring functional microRNAs and proteins. This review will summarize the therapeutic role of stem cell EVs in reversing aging and cancer, which suggests the broad clinical application perspective.

The V369M Gcgr knock-in mice are a precision medicine model of mild Mahvash disease.

The detailed metabolic characterization of the glucagon receptor (Gcgr)V369M+/+ mutant mice described in Lin et al. in the Biochemical Journal is of interest and resulting in the expected metabolic profile. We would like to point out that these mice might also be extremely useful as a precision medicine model of mild Mahvash disease, a rare hereditary pancreatic neuroendocrine tumor syndrome characterized by inactivating mutations in the glucagon receptor. Further characterization of pancreas morphology and histology in the GcgrV369M+/+ mice at more advanced ages will be critically important to understand mild Mahvash disease in humans.

[Effects of different storage conditions on edible quality and antioxidant activity of Polygonatum cyrtonema flowers].

The flower of Polygonatum cyrtonema has good edible and medicinal values. In this study, four samples of P. cyrtonema flowers from different regions were selected as test materials. The contents, composition and antioxidant activities of lipid-soluble pigments and alcohol-soluble components were determined under different light and temperature conditions, which help to reveal the discoloration reason and the composition variation patterns during storage. The results showed that light and temperature had different effects on the lipid-soluble pigments and alcohol-soluble components in the dried flowers during storage. After storage for 4 weeks, the contents of total chlorophyll, carotenoids, phenols and saponins in the samples exposed to light respectively decreased by 62.62%, 66.4%, 68.7% and 43.4% compared with those in the dark. The decreases in the contents of chlorophyll a, chlorophyll b, lutein, ß-carotene and zeaxanthin were 64.64%, 56.74%, 59.2%, 77.7% and 45.4%, respectively. The contents of pigments and components in the samples stored at-20 ℃ were significantly higher than those at room temperature and 4 ℃, indicating that low temperature was conductive to the stability of lipid-soluble pigments and alcohol-soluble components. The samples stored at low temperature and in the dark had the strongest free radical scavenging activity. The results suggest that P. cyrtonema dried flowers should be stored in low temperature environment without light, which can slow down the degradation of internal components. The study provides a theoretical basis for the production, processing and storage of P. cyrtonema flowers.

Shock Wave Energy Absorption in Metal-Organic Framework.

Recent investigations into the mechanical properties and mechanochemical reactions of metal-organic frameworks (MOFs) have suggested the potential for energy dissipation by multiple mechanisms. Although the possibility of efficient multifunctional shock dissipation by MOFs was suggested by static high pressure studies, there is little known about MOFs under shock compression. Here, we measure the attenuation of shock wave by the MOF denoted zeolitic-imidazolate framework (ZIF-8) in its desolvated, porous state. We find that shock wave dissipation by ZIF-8 occurred by multiple processes: powder compaction, nanopore-collapse, and chemical bond-breakage. The shock energy absorbance in ZIF-8 is proportional to ZIF-8 thickness, allowing the prediction of the thickness of MOF layer needed to attenuate shock waves to a desired lower energy. Compared with PMMA, often used as a standard, ZIF-8 attenuates 7 times more shock energy per unit mass for impacts at a lower velocity of 0.75 km/s and 2.5 times more at a higher velocity of 1.6 km/s. This research illustrates how to improve the ability to attenuate shock waves for personnel and equipment protection by engineering multifunctionality into the shock wave absorbing armor material.

Foxa2, a novel protein partner of the tumour suppressor menin, is deregulated in mouse and human MEN1 glucagonomas.

Foxa2, known as one of the pioneer factors, plays a crucial role in islet development and endocrine functions. Its expression and biological functions are regulated by various factors, including, in particular, insulin and glucagon. However, its expression and biological role in adult pancreatic α-cells remain elusive. In the current study, we showed that Foxa2 was overexpressed in islets from α-cell-specific Men1 mutant mice, at both the transcriptional level and the protein level. More importantly, immunostaining analyses showed its prominent nuclear accumulation, specifically in α-cells, at a very early stage after Men1 disruption. Similar nuclear FOXA2 expression was also detected in a substantial proportion (12/19) of human multiple endocrine neoplasia type 1 (MEN1) glucagonomas. Interestingly, our data revealed an interaction between Foxa2 and menin encoded by the Men1 gene. Furthermore, using several approaches, we demonstrated the relevance of this interaction in the regulation of two tested Foxa2 target genes, including the autoregulation of the Foxa2 promoter by Foxa2 itself. The current study establishes menin, a novel protein partner of Foxa2, as a regulator of Foxa2, the biological functions of which extend beyond the pancreatic endocrine cells. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Interpretation of Unexpectedly High Levels of Endocrine Tumor Markers.

OBJECTIVE: Endocrine tumor markers (ETMs) are important and indispensable tools in the diagnosis and follow-up of endocrine tumors. Unexpectedly high level of ETM (UHLETM) is often encountered in clinical practice. The objectives of this article are to discuss the approach to UHLETMs and describe the most common UHLETMs. METHODS: Literature review and personal experience with UHLETMs. RESULTS: A UHLETM is defined as an ETM level much higher than what an endocrinologist would expect based on the patient's clinical information, other biochemical test results, and imaging findings. Most UHLETMs are false positive, in that they do not indicate the existence or growth of an endocrine tumor. The key issue, however, is how to convincingly prove that a UHLETM is false positive. The most important question to help resolve UHLETMs is whether the UHLETMs are due to false or true results. Some UHLETMs are due to interpretation errors, laboratory errors, or spurious test results, while the true levels of the ETMs are normal or unchanged from previous results. Other UHLETMs are due to nontumor conditions or medications, and the true levels of the ETMs are indeed very high. When it is not straightforward to assess whether certain UHLETMs are due to false or true results, they may be due to novel conditions. CONCLUSION: UHLETMs provide endocrinologists great opportunities to learn the basic biology and measurement of ETMs. Unresolved UHLETMs are exciting clinical research opportunities which may lead to discovery of new diseases and new mechanisms of measurement interference. ABBREVIATIONS: 5-HIAAA = 5-hydroxyindoleacetic acid; 5-HTP = 5-hydroxytryptophan; CGA = chromogranin A; ETM = endocrine tumor marker; MTC = medullary thyroid carcinoma; UHLETM = unexpectedly high level of endocrine tumor marker.

Energy Storage during Compression of Metal-Organic Frameworks.

Practical applications of metal-organic framework (MOF) materials require an in-depth understanding of their mechanical properties. We have investigated the mechanical properties and energy absorption behavior of single crystals of four isostructural UiO-type MOFs under uniaxial compression. In situ nanocompression experiments were used to measure the mechanical behavior of individual MOF nanocrystals under compression within a transmission electron microscope. The plasticity and endothermicity during deformation of MOFs shows a surprising potential for absorption and dissipation of mechanical shock. At compressive stress below 2 GPa, relatively small amounts of energy (<0.3 kJ/g) are absorbed by the compression of these MOFs. As the stress was increased, however, the energy absorption was significantly enhanced. Above 2 GPa, the energy absorption typically reaches 3-4 kJ/g; for comparison, the energy release in the explosion of TNT is ∼4 kJ/g. Gram for gram, MOFs can absorb as much energy as a high explosive can release.

Shock Wave Chemistry in a Metal-Organic Framework.

Metal-organic frameworks (MOFs) have potential applications as energy absorbing materials for shock wave energy mitigation due to their nanoporosity. Here we have examined km/s laser-driven flyer plate impacts on a prototypical MOF, ZIF-8. We observed particle fragmentation and morphological changes in microcrystals of ZIF-8 at lower shock pressures (≈2.5 GPa), and amorphization and structural collapse at higher pressures (≈8 GPa). High-speed emission spectroscopy revealed that 50 ns after flyer plate impacts, an emission pulse was generated by ZIF-8 resulting from chemical bonds that were broken and subsequently reformed. MOFs may prove useful in the dissipation of shock wave energy through large structural changes (free volume collapse and endothermic bond breakage).

Impact of Shape Persistence on the Porosity of Molecular Cages.

Porous materials provide a plethora of technologically important applications that encompass molecular separations, catalysis, and adsorption. The majority of research in this field involves network solids constructed from multitopic constituents that, when assembled either covalently or ionically, afford macromolecular arrangements with micro- or meso-porous apertures. Recently, porous solids fabricated from discrete organic cages have garnered much interest due to their ease of handling and solution processability. Although this class of materials is a promising alternative to network solids, fundamental studies are still required to elucidate critical structure-function relationships that govern microporosity. Here, we report a systematic investigation of the effects of building block shape-persistence on the porosity of molecular cages. Alkyne metathesis and edge-specific postsynthetic modifications afforded three organic cages with alkynyl, alkenyl, and alkyl edges, respectively. Nitrogen adsorption experiments conducted on rapidly crystallized and slowly crystallized solids illustrated a general trend in porosity: alkynyl > alkenyl > alkyl. To understand the molecular-scale origin of this trend, we investigated the short and long time scale molecular motions of the molecular cages using ab initio molecular dynamics (AIMD) and classical molecular dynamics (MD) simulations. Our combined experimental and computational results demonstrate that the microporosity of molecular cages directly correlates with shape persistence. These findings discern fundamental molecular requirements for rationally designing porous molecular solids.

Are patients with hormonally functional phaeochromocytoma and paraganglioma initially receiving a proper adrenoceptor blockade? A retrospective cohort study.

OBJECTIVE: Pharmacological treatment is mandatory in patients with hormonally functional phaeochromocytoma and paraganglioma (PHAEO/PGL). We evaluated if patients initially diagnosed with hormonally functional PHAEO/PGL by various medical subspecialties received proper adrenoceptor blockade, and analysed factors predicting the prescription of adequate treatment. METHODS: In a retrospective cohort study, we reviewed data from patients initially diagnosed with hormonally functional PHAEO/PGL outside the National Institutes of Health and Cedars-Sinai Medical Center, who were referred to these institutions between January 2001 and April 2015. Logistic regression was used to assess factors associated with proper adrenoceptor blockade. RESULTS: A total of 381 patients were included. Adequate pharmacological treatment was prescribed to 69·3%, of which 93·1% received α-adrenoceptor blockers. Regarding patients who were inappropriately treated, 53% did not receive any medication. Independent predictors of the prescription of a proper blockade were the diagnosis by endocrinologists [odds ratio (OR) 4·14; 95% confidence interval (CI), 2·51-6·85; P < 0·001], the presence of high blood pressure (OR 5·94; 95% CI, 3·11-11·33; P < 0·001) and the evidence of metastasis (OR 5·96; 95% CI, 1·93-18·46; P = 0·002). CONCLUSIONS: Although most patients received adequate pharmacological treatment, almost one-third were either not treated or received inappropriate medications. The diagnosis by endocrinologists, the presence of high blood pressure and the evidence of metastatic disease were identified as independent predictors of a proper blockade. These results highlight the need to educate physicians about the importance of starting adequate adrenoceptor blockade in all patients with hormonally functional PHAEO/PGL.

Compression-induced deformation of individual metal-organic framework microcrystals.

The deformation and mechanical behavior of individual zeolitic-imidazolate framework (ZIF-8) micro- and sub-microcrystals were observed under compression. Young's modulus and volume changes as a function of applied pressure were determined on individual single crystals, offering insights in the relationship among structure, morphology, and mechanical properties. Dramatic volume decreases and amorphization were detected during compression over a pressure range of 0-4 GPa for individual 1.2 µm ZIF-8 microcrystals, and the deformed microcrystals partially recovered after pressure release. The orientation and size effects on the mechanical behavior of ZIF-8 nano- and microcrystals were also investigated. The presence of solvates within the pores of the ZIF-8 has a dramatic effect on the mechanical properties of the single crystals. Methanol-solvated ZIF-8 microcrystals are much less deformable than the desolvated microcrystals and shatter completely at very low applied force.

BCYRN1, a c-MYC-activated long non-coding RNA, regulates cell metastasis of non-small-cell lung cancer.

BACKGROUND: Long non-coding RNAs (lncRNAs) are increasingly implicated in the regulation of the progression of malignancy. AIM: To clarify the relations among BCYRN1 (brain cytoplasmic RNA 1, a long non-coding RNA), c-MYC and cell metastasis of non-small-cell lung cancer (NSCLC). METHODS: Real-time PCR was used to measure expression of BCYRN1 in NSCLC. Knockdown and overexpression of c-MYC were respectively performed using shRNA and lentivirus to investigate its effect on BCYRN1 expression. BCYRN1 was respectively knockdown and overexpressed by siRNA and BCYRN1 mimics to investigate its role in regulating cell metastasis in vitro. ChIP (chromatin immunoprecipitation) assay was performed to confirm the binding of c-MYC to the promoter of BCYRN1. Expression levels of matrix metalloproteinases (MMP9 and MMP13) were determined using real-time PCR and Western blotting. RESULTS: BCYRN1 is upregulated and targeted by c-MYC in NSCLC, leading to the increase of cell motility and invasiveness. RNA interference and lentivirus infection showed a positive correlation between the expressions of c-MYC and BCYRN1. ChIP assay confirmed the binding of c-MYC to the promoter region of BCYRN1 gene. In-vitro cell metastasis experiments demonstrated that BCYRN1 was necessary in the c-MYC-regulated cell migration and invasion. The mRNA and protein expression levels of MMP9 and MMP13 descended with the decreasing BCYRN1 level and ascended with the upregulation of BCYRN1. CONCLUSION: These findings uncover a regulatory mechanism in NSCLC cells involving the metastasis-promoting lncRNA BCYRN1 that improves expressions of the key metastasis-supporting proteins MMP9 and MMP13.

Nuclear imaging of neuroendocrine tumors with unknown primary: why, when and how?

Neuroendocrine tumors (NETs) with unknown primary (CUP-NET) are associated with a poor prognosis (10-year survival 22%), grade 1 and 2 NETs having a more favorable outcome than grade 3 (also called carcinoma). There is evidence that an effort should be made to localize the primary tumor even in the presence of metastasis because resection of the primary tumor(s) may improve disease-free and overall survival, and because the choice of chemotherapeutic agent depends on the location of the primary tumor. Localization of the tumors remains challenging and often relies on a combination of radiological, endoscopic and functional imaging. The functional imaging protocol for evaluation of these patients has historically relied on somatostatin receptor scintigraphy (SRS). However, the sensitivity and specificity of SRS may be unsatisfactory, especially for NETs of midgut origin. Newer PET radiotracers such as (68)Ga-labeled somatostatin analogs ((68)Ga-DOTA-SSTa) and (18)F-DOPA have shown promise. In direct comparisons between (68)Ga-DOTA-SSTa PET/CT and (99m)Tc-HYNIC-octreotide/(111)In-pentetreotide SPECT(/CT), (68)Ga-DOTA-SSTa performed better than other techniques, giving a compelling reason for switching from SPECT/CT to PET/CT imaging. (18)F-DOPA performs better than SRS and CT in well-differentiated NETs of the small intestine. For detecting pancreatic NETs, the high background uptake of (18)F-DOPA by the normal exocrine pancreas can be somewhat overcome by pretreatment with carbidopa. We have suggested a protocol in which SRS is replaced by one of the two agents (preferably with (68)Ga-DOTA-SSTa, alternatively (18)F-DOPA) as first-line nuclear tracer for detection of CUP-NET in patients with well-differentiated NETs and (18)F-FDG PET/CT may be an additional diagnostic test for poorly differentiated tumors and for prognostication. In the near future, it is expected that patients with CUP-NET will benefit from newly developed PET approaches (radiopharmaceuticals) and intraoperative PET imaging.