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Vertebrates need to maintain extracellular chloride (Cl–) concentrations to ensure the normal operation of physiological processes; the transition from aquatic to terrestrial environments necessitated the development of sophisticated mechanisms to ensure Cl– homeostasis in the face of fluctuating Cl– levels. Zebrafish calcitonin gene-related peptide (CGRP), unlike its splice variant calcitonin, does not respond to environmental Ca2+ levels. This study aimed to test the hypothesis that CGRP is involved in the control of body fluid Cl– homeostasis. Acclimation to high-Cl– artificial water stimulated the mRNA expression of cgrp and the receptor (crlr1) when compared with low- Cl–. CGRP knockdown induced upregulation of the Na+-Cl– co-transporter (ncc2b), while overexpression of CGRP resulted in the downregulation of ncc2b mRNA synthesis and a simultaneous decrease in Cl– uptake in embryos. Consistent with these findings, knockdown of either cgrp or crlr1 was found to increase the density of NCC2b-expressing cells in embryos. This is the first demonstration that CGRP acts as a hypochloremic hormone through suppressing NCC2b expression and the differentiation of NCC-expressing ionocytes. Elucidation of this novel function of CGRP in fish body fluid Cl– homeostasis promises to enhance our understanding of the related physiology in vertebrates. [ABSTRACT FROM AUTHOR]

Introduction: In mammals, internal Na+ homeostasis is maintained through Na+ reabsorption via a variety of Na+ transport proteins with mutually compensating functions, which are expressed in different segments of the nephrons. In zebrafish, Na+ homeostasis is achieved mainly through the skin/gill ionocytes, namely Na+/H+ exchanger (NHE3b)-expressing H+-ATPase rich (HR) cells and Na+-Cl- cotransporter (NCC)-expressing NCC cells, which are functionally homologous to mammalian proximal and distal convoluted tubular cells, respectively. The present study aimed to investigate whether or not the functions of HR and NCC ionocytes are differentially regulated to compensate for disruptions of internal Na+ homeostasis and if the cell differentiation of the ionocytes is involved in this regulation pathway. Results: Translational knockdown of ncc caused an increase in HR cell number and a resulting augmentation of Na+ uptake in zebrafish larvae, while NHE3b loss-of-function caused an increase in NCC cell number with a concomitant recovery of Na+ absorption. Environmental acid stress suppressed nhe3b expression in HR cells and decreased Na+ content, which was followed by up-regulation of NCC cells accompanied by recovery of Na+ content. Moreover, knockdown of ncc resulted in a significant decrease of Na+ content in acid-acclimated zebrafish. Conclusions: These results provide evidence that HR and NCC cells exhibit functional redundancy in Na+ absorption, similar to the regulatory mechanisms in mammalian kidney, and suggest this functional redundancy is a critical strategy used by zebrafish to survive in a harsh environment that disturbs body fluid Na+ homeostasis. [ABSTRACT FROM AUTHOR]

Diabetes can be associated with a reduction in functional β cell mass, which must be restored if the disease is to be cured or progress is to be arrested. To study the cell count, it is also necessary to determine the number of nuclei within the insulin stained area. It can take a single experimentalist several months to complete a single study of this kind, results of which may still be quite subjective. In this paper, we propose a framework based on a novel measure of local symmetry for detection of cells. The local isotropic phase symmetry measure (LIPSyM) is designed to give high values at or near the cell centers. We demonstrate the effectiveness of our algorithm for detection of two types of specific cells in histology images, cells in mouse pancreatic sections and lymphocytes in human breast tissue. Experimental results for these two problems show that our algorithm performs better than human experts for the former problem, and outperforms the best reported results for the latter. [ABSTRACT FROM AUTHOR]

The thiazide-sensitive NaCl- cotransporter (NCC), a member of the SLC12 family, is mainly expressed in the apical membrane of the mammalian distal convoluted tubule (DCT) cells, is responsible for cotransporting Na+ and Cl- from th lumen into DCT cells and plays a major role in the mammalian renal NaCl reabsorption. The NCC has also been reported in fish, but the functional role in fish ion regulation is yet unclear. The present study used zebrafish as an in vivo model to test the hypothesis of whether the NCC plays a role in Na+ and/or Cl- uptake mechanisms. Four NCCs were cloned, and only one of them, zebrafish (z) slcl2a10.2 was found to predominately and specifically be expressed in gills. Double in situ hybridization/immunocytochemistry in zebrafish skin/gills demonstrated that the specific expression of zslcl2a10.2 mRNA in a novel group of ionocytes differed from those of the previously-reported H+-ATPase-rich (HR) cells and Na+-KATPase rich (NaR) cells. Gill mRNA expression of zslcl2a10.2 was induced by a low-Cl- environment that stimulated fish Cl- influx, while a low-Na environment suppressed this expression. Incubation with metolazone, a specific inhibitor of the NCC, impaired both Na and Cl- influx in 5-day postfertilization (dpf) zebrafish embryos. Translational knockdown of zslcl2a10.2 with a specific morpholino caused significant decreases in both Cl- influx and Cl- content of 5-dpf zebrafish embryos, suggesting that the operation of zNCC-like 2 result in a net uptake of Cl- in zebrafish. On the contrary, zslcl2a10.2 morphants showed increased Na influx and content that resulted from upregulation of mRNA expressions of Na+-H+ exchanger 3b and carbonic anhydrase 15a in HR cells. These results for the first time provide in vivo molecular physiological evidence for the possible role of the NCC in the Cl- uptake mechanism in zebrafish skin/gills. [ABSTRACT FROM AUTHOR]

In recent years, small animal image-guided irradiators have been widely utilized in preclinical studies involving rodent models. However, the dosimetry commissioning of such equipment involving kilovoltage small-field dosimetry has not received as much interest as the megavoltage small-field dosimetry used clinically. To date, a paucity of measured kilovoltage beam data, especially for field sizes less than 3 mm, can be found in the literature. For improvement of rodent treatments in the future, this work aims to provide comprehensive and accurate beam data for the small animal radiation research platform (SARRP, Xstrahl) using EBT3 Gafchromic films and Monte Carlo calculation, with submillimeter resolution and accuracy. This work includes three primary tasks: (1) establish an optimized film measurement protocol for small field dosimetry of kilovoltage photon beam. (2) Acquire dosimetric data including (a) depth dose curves from the surface to 6 cm depth (b) beam profiles, (c) penumbra, (d) cone factors and (e) 2D dose distribution. These tasks were undertaken for a 220 kVp photon beam with five different small field widths and 33 cm source to surface distance (0.5 mm and 1 mm circular fields, 3  ×  3 mm2, 5  ×  5 mm2, 10  ×  10 mm2 square fields). Beam data was measured with EBT3 films. (3) Provide comparative dosimetry for film measurements, Monte Carlo calculations, and the dose calculations performed with the SARRP treatment planning system, Muriplan. For the majority of parameters, film measurement agreed with Monte Carlo simulation within 1%. There were, however, discrepancies between measured beam data and Muriplan treatment planning data. Specifically, for PDD, Muriplan underestimates the dose for field sizes of 0.5 mm and 1 mm. For beam profiles comparisons, the calculation from Muriplan predicts a smaller lateral distance between the 50% isodose lines compared to film measurement. There is a difference of 0.18, 0.72, 0.6 mm between Muriplan and film for field sizes of 3, 5, 10 mm, respectively. This work demonstrates that accurate and precise kilovoltage small-field dosimetry can be conducted using EBT3 Gafchromic film with an optimized protocol. In addition, discrepancies between measured beam data and Muriplan were identified. [ABSTRACT FROM AUTHOR]

A foreword to “International Journal of Modern Physics A,” is presented.

Objective: Mumps is a seasonal infectious disease, always occurring in winter and spring. In this study, we aim to analyze its epidemiological characteristics, transmissibility, and its correlation with meteorological variables. Method: A seasonal SusceptibleeExposedeInfectious/AsymptomaticeRecovered model and a next-generation matrix method were applied to estimate the time-dependent reproduction number (Rt). Results: The seasonal double peak of annual incidence was mainly in May to July and November to December. There was high transmission at the median of Rt - 1.091 (ranged: 0 to 4.393). Rt was seasonally distributed mainly from February to April and from September to November. Correlations were found between temperature (Pearson correlation coefficient [r] ranged: from 0.101 to 0.115), average relative humidity (r - 0.070), average local pressure (r - -0.066), and the number of new cases. In addition, average local pressure (r - 0.188), average wind speed (r - 0.111), air temperature (r ranged: -0.128 to -0.150), average relative humidity (r - -0.203) and sunshine duration (r - -0.075) were all correlated with Rt. Conclusion: A relatively high level of transmissibility has been found in Xiamen City, leading to a continuous epidemic of mumps. Meteorological factors, especially air temperature and relative humidity, may be more closely associated with mumps than other factors. [ABSTRACT FROM AUTHOR]

Cohesin and CTCF are major drivers of 3D genome organization, but their role in neurons is still emerging. Here, we show a prominent role for cohesin in the expression of genes that facilitate neuronal maturation and homeostasis. Unexpectedly, we observed two major classes of activity-regulated genes with distinct reliance on cohesin in mouse primary cortical neurons. Immediate early genes (IEGs) remained fully inducible by KCl and BDNF, and short-range enhancer-promoter contacts at the IEGs Fos formed robustly in the absence of cohesin. In contrast, cohesin was required for full expression of a subset of secondary response genes characterized by long-range chromatin contacts. Cohesin-dependence of constitutive neuronal genes with key functions in synaptic transmission and neurotransmitter signaling also scaled with chromatin loop length. Our data demonstrate that key genes required for the maturation and activation of primary cortical neurons depend on cohesin for their full expression, and that the degree to which these genes rely on cohesin scales with the genomic distance traversed by their chromatin contacts. [ABSTRACT FROM AUTHOR]

The following sections are included: Overview of the BES-III Detector BES-III Offline Software Main Drift Chamber Time-Of-Flight System Electromagnetic Calorimeter Muon Identifier Trigger [ABSTRACT FROM AUTHOR]