DOCK4 regulates ghrelin production in gastric X/A-like cells

PURPOSE

Ghrelin, a gastric hormone, provides a hunger signal to the central nervous system to stimulate food intake. Ghrelin also modulates neuroinflammatory and apoptotic processes. Dedicator of cytokinesis 4 (DOCK4), a guanine nucleotide exchange factor (GEF), is involved in the regulation of neuronal polarization and axon regeneration. However, the effect of DOCK4 on ghrelin production has not been explored.

METHODS

The expression of DOCK4 in human and mouse stomach was examined by immunohistochemical staining. The synthesis and secretion of ghrelin in Dock4 null mice were evaluated by real-time quantitative PCR, Western blot and ELISA. The effects of DOCK4 on ghrelin production in mHypoE-42 cells were measured by real-time quantitative PCR and Western blot.

RESULTS

We showed that DOCK4 was expressed in both human and mouse gastric ghrelin cells. The mRNA and protein levels of gastric ghrelin, as well as ghrelin secretion, were remarkably diminished in Dock4 null mice. Furthermore, we showed that overexpression of Dock4 significantly stimulated ghrelin expression, while siRNA knockdown of endogenous Dock4 resulted in a marked decrease of ghrelin in mHypoE-N42 cells.

CONCLUSIONS

Our results identify DOCK4 as a critical regulator for ghrelin production in gastric X/A-like cells.

Caloric restriction and Roux-en-Y Gastric Bypass promote white adipose tissue browning in mice

PURPOSE

Caloric restriction (CR) and Roux-en-Y Gastric Bypass (RYGB) are considered effective means of body weight control, but the mechanism by which CR and RYGB protect against high-fat diet (HFD)-induced obesity remains elusive. The browning of white adipose tissue (WAT) is a potential approach to combat obesity. Here we assess whether browning of WAT is involved in CR- and RYGB-treatment.

METHODS

The average size of adipocytes was determined by histological analysis. Expression of thermogenic genes in both human subjects and mice were measured by quantitative real-time PCR and immunohistochemical staining.

RESULTS

The average size of adipocytes was bigger, while the expression of thermogenic genes such as uncoupling protein 1 (UCP1), nuclear factor erythroid-2 like 1 (NRF1) and PPARγ coactivator-1 α (PGC1α) were lower in the WAT of obese subjects when compared to lean controls. Both CR and RYGB promoted weight and fat loss. Increment of the average adipocytes size and down-regulation of thermogenic genes were significantly reversed by both CR and RYGB in the WAT of obese mice.

CONCLUSIONS

Our findings showed that CR and RYGB significantly improved high-fat diet-induced lipid accumulation by promoting the browning of WAT.

Effects of acids, pepsin, bile acids, and trypsin on laryngopharyngeal reflux diseases: physiopathology and therapeutic targets

PURPOSE

Laryngopharyngeal reflux disease (LPRD) is a general term for the reflux of gastroduodenal contents into the laryngopharynx, oropharynx and even the nasopharynx, causing a series of symptoms and signs. Currently, little is known regarding the physiopathology of LPRD, and proton pump inhibitors (PPIs) are the drugs of choice for treatment. Although acid reflux plays a critical role in LPRD, PPIs fail to relieve symptoms in up to 40% of patients with LPRD. The influence of other reflux substances on LPRD, including pepsin, bile acid, and trypsin, has received increasing attention. Clarification of the substances involved in LPRD is the basis for LPRD treatment.

METHODS

A review of the effects of acids, pepsin, bile acids, and trypsin on laryngopharyngeal reflux diseases was conducted in PubMed.

RESULTS

Different reflux substances have different effects on LPRD, which will cause various symptoms, inflammatory diseases and neoplastic diseases of the laryngopharynx. For LPRD caused by different reflux substances, 24-h multichannel intraluminal impedance combined with pH-metry (MII-pH), salivary pepsin, bile acid and other tests should be established so that different drugs and treatment courses can be used to provide patients with more personalized treatment plans.

CONCLUSION

This article summarizes the research progress of different reflux substances on the pathogenesis, detection index and treatment of LPRD and lays a theoretical foundation to develop target drugs and clinical diagnosis and treatment.

Immunohistochemical Characterization of H3K4Me3 in Reactive Lymph Nodes and Follicular Lymphoma

Introduction/Objective

Genes involved in histone methylation are frequently mutated in non-Hodgkin’s lymphomas. For instance, frequent mutations in genes encoding histone methytransferases MML2 and EZH2 are present in diffuse large B cell lymphoma (DLBCL) and follicular lymphoma (FL). The aim of this study was to characterize the immunohistochemical expression of H3K4Me3 in benign/reactive lymph nodes (LNs) with comparison to follicular lymphoma (FL).

Methods/Case Report

Immunohistochemical staining with an anti-H3K4Me3 antibody was performed on FFPE whole slide section from patients with benign/reactive LNs (n=21), low grade (grade 1-2) FL (n=21). H3K4Me3 reactivity was scored for staining intensity and percentage of lymphocytes showing reactivity.

Results (if a Case Study enter NA)

The majority of the reactive LN sections (15 out of 21 cases) showed a distinct distribution of H3K4Me3 staining, with the majority of cells in the mantle zone and the interfollicular zones showing moderate-strong staining, whereas reactive germinal centers (GCs) showed significantly decreased or close to negative staining. Neoplastic follicles in all the FL cases contained positive cells with significantly stronger staining compared to that in the germinal centers in benign lymph nodes. The interfollicular zones, while diminished in FL due to expanded neoplastic follicles, showed retained H3K4Me3 staining. The difference in staining intensity between follicles and mantle/interfollicular zones became indistinct in FL.

Conclusion

H3K4Me3 expression in benign/reactive LNs is characterized by positive expression in lymphocytes in interfollicular and mantle zones and significantly decreased in GCs. However, the expression pattern is different in FL, which showed significantly increased expression in the follicles compared to that in reactive GCs. In FL, the expression in GCs is similar to that in the interfollicular and mantle zone lymphocytes. It is reported that about 90% of FL have MLL2 mutation and MLL2 is the enzyme responsible for the methylation of H3K4. So far, it is unclear whether the mutation of MLL2 in FL affects the overall methylation activity of the enzyme. In our study, there is increased methylation of H3K4 in the follicles of FL, which raises the possibility that MLL2 mutation somehow increases H3K4 methylation.

E_{8} Spectra of Quasi-One-Dimensional Antiferromagnet BaCo_{2}V_{2}O_{8} under Transverse Field

We report ^{51}V NMR and inelastic neutron scattering (INS) measurements on a quasi-1D antiferromagnet BaCo_{2}V_{2}O_{8} under transverse field along the [010] direction. The scaling behavior of the spin-lattice relaxation rate above the Néel temperatures unveils a 1D quantum critical point (QCP) at H_{c}^{1D}≈4.7  T, which is masked by the 3D magnetic order. With the aid of accurate analytical analysis and numerical calculations, we show that the zone center INS spectrum at H_{c}^{1D} is precisely described by the pattern of the 1D quantum Ising model in a magnetic field, a class of universality described in terms of the exceptional E_{8} Lie algebra. These excitations are nondiffusive over a certain field range when the system is away from the 1D QCP. Our results provide an unambiguous experimental realization of the massive E_{8} phase in the compound, and open a new experimental route for exploring the dynamics of quantum integrable systems as well as physics beyond integrability.

Vibration modes of a transportable optical cavity

Many factors still need to be evaluated to fully understand the physical mechanisms determining optical cavity vibration, which are crucial for designing and constructing a transportable ultra-stable laser. Herein, a detailed dynamic analysis is used to characterize the vibration modes of a transportable optical cavity. The first five resonance modes are identified in the presence of a cavity support, and the guidelines to achieve a high first-order resonance frequency are proposed; thereby, high robustness is described using a 50 mm length optical cavity. The results demonstrate that the first-order resonance of up to 681 Hz with a gross weight of 2.51 kg can be achieved using an optimization strategy for given cavity support. The theoretical results are consistent with simulation and experiment. With the optimal group, a 1.34 Hz linewidth transportable ultra-stable laser at 1550 nm is established, and a linewidth of 1.5 Hz and frequency instability of 9.5×10^-15@1s are obtained after the test including 100 km actual road transportation and 34 min continuous vibration. The test condition is equivalent to ∼ 1000 km road transportation. Our method can be readily extended to other transportable optical cavities, providing a powerful tool for improving the robustness of vibration, particularly important for transportable environments.

[Otological and hearing characteristics in children with Turner syndrome]

Objective: To explore the otological and hearing characteristics in children with Turner syndrome (TS), to determine risk factors of hearing loss, and to discuss algorithms for future surveillance. Methods: The clinical data of otolaryngology in children with TS from January 2018 to April 2020 were reviewed retrospectively. A total of 46 female children with TS, aged from 5 to 18 years were enrolled. Karyotypes included 17 cases (37.0%) of monosomy, 16 cases (34.7%) of mosaicism, and 13 cases (28.3%) of abnormal X chromosome structures. The otoscopic characteristics, audiological performance, and otologic diagnoses were evaluated. Multivariate logistic regression and Mann-Whitney U test were used for statistical analysis. Results: The most common otologic comorbidity was otitis media with effusion (OME), including 20 cases (43.5%) with 33 ears (35.9%). 14 cases (30.4%) were diagnosed with hearing loss. The regression analysis revealed that the age (OR=1.345, 95%CI: 1.072-1.760) and comorbidity of OME (OR=9.460, 95%CI: 2.065-60.350) were risk factors associated with hearing loss. In TS with OME, when compared with the mean air conduction threshold, the hearing loss of the group with pars flaccida retractions was significantly higher ((24.3±13.8) dB HL vs. (14.4±4.2) dB HL, U=59.500, P=0.008) than that of the group with none retractions. Conclusion: OME and hearing loss are common in children with TS. As age increases or suffers from OME, the risk of hearing loss increases.

The interface between paediatrics and camhs (child and adolescent psychiatry): Mental state examination teaching for paediatric trainees

Introduction

During an out-of-hours shift, the initial assessment of a CAMHS patient is performed by the paediatric trainee, usually the paediatric SHO (senior-house-officer). During my placement as a paediatric SHO, I was aware of a gap in formalised metal state examination teaching for paediatric juniors, which would be crucial for a thorough assessment of these patients, and to better guarantee they are safely managed until further assessment.

Objectives

The aim is to provide a short teaching session on mental state examining of the CAMHS patent to paediatric SHOs in order to improve their confidence in assessment.

Methods

In order to assess initial confidence in assessing the mental-state of a CAMHS patient, a pre-teaching questionnaire was given to the paediatric SHOs. A 30-minute teaching session on the mental state exam was then carried out and a post-teaching questionnaire was then given to the same trainees.

Results

Paired sample Wilcoxons signed rank test found that training significant improved trainees’ confidence in taking a psychiatric mental state exam (p= 0.005, r = 0.628), and improved their confidence in presenting a mental state exam (p = 0.0041, r = 0.6420).

Conclusions

Being able to confidently assess the mental state of a CAMHS patient in an on call shift is important for the initial assessing paediatric trainee. However this is often not taught in the paediatric curriculum and trainees have expressed some anxiety in performing this assessment overnight, before a more comprehensive assessment by a CAMHS professional. A simple teaching session may help to reduce this anxiety and improve trainees’ confidence.

[Research advances on mechanism of exosomes derived from adipose derived stem cells in the treatment of chronic wounds]

Exosomes are a kind of membrane vesicle with a diameter of 30-150 nm. It is formed by the budding of multiple vesicles in cells, which can fuse with the cell membrane and be released into the extracellular matrix. Adipose derived stem cells (ADSCs) have the potential of self-renewal and multi-directional differentiation. They can transport the active substance, regulate the inflammatory response, cell migration, proliferation, differentiation and angiogenesis via the action of paracrine exosomes, so as to enhance the ability of wound repair, promote wound healing, and inhibit the formation of scars. Chronic wounds refer to the wounds that can not reach the anatomic and functional integrity through the normal, orderly, and timely repair process, and the course of the wound healing is more than 4 weeks. At present, there are various treatment methods for chronic wounds, among which ADSCs, although showing a good application prospect, have some limitations due to ethical issues, while exosomes can avoid this problem. This article reviews the treatment of chronic wounds with ADSC exosomes.

Cytokine storm syndrome in coronavirus disease 2019: A narrative review

Cytokine storm syndrome (CSS) is a critical clinical condition induced by a cascade of cytokine activation, characterized by overwhelming systemic inflammation, hyperferritinaemia, haemodynamic instability and multiple organ failure (MOF). At the end of 2019, the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan, China, and rapidly developed into a global pandemic. More and more evidence shows that there is a dramatic increase of inflammatory cytokines in patients with COVID-19, suggesting the existence of cytokine storm in some critical illness patients. Here, we summarize the pathogenesis, clinical manifestation of CSS, and highlight the current understanding about the recognition and potential therapeutic options of CSS in COVID-19.

[The problems and countermeasures in the training of public health talents in colleges and universities in China]

Colleges and universities are the cradle for public health talents training. Under the epidemic situation, the new requirements for the construction of public health service system and the promotion of population health, urged us to rethink how to reform the training of public health talents in colleges and universities. This research focused on key problems of the construction and distribution, scale, orientation, and contents of training for various public health talents in colleges and universities. It was suggested to reinforce the balanced development of public health in colleges and universities in various areas in China, to refine interdisciplinary training, to intensively cultivate technical and research-oriented talents, to expand talents within and outside the colleges and universities, as well as to introduce and cultivate public health teachers simultaneously, so as to better play the role of colleges and universities in the training of the public health talents.

HSP70 inhibits pig pituitary gonadotrophin synthesis and secretion by regulating the corticotropin-releasing hormone signaling pathway and targeting SMAD3

High levels or long periods of stress have been shown to negatively impact cell homeostasis, including with respect to abnormalities in domestic animal reproduction, which are typically activated through the hypothalamus-pituitary-adrenal axis, in which corticotropin-releasing hormone (CRH) and heat shock protein 70 (HSP70) are involved. In addition, CRH has been reported to inhibit pituitary gonadotrophin synthesis, and HSP70 is expressed in the pituitary gland. The aim of this study was to determine whether HSP70 was involved in regulating gonadotrophin synthesis and secretion by mediating the CRH pathway in the porcine pituitary gland. Our results showed that HSP70 was highly expressed in the porcine pituitary gland, with over 90% of gonadotrophic cells testing HSP70 positive. The results of functional studies demonstrated that the HSP70 inducer decreased FSH and LH levels in cultured porcine primary pituitary cells, whereas an HSP70 inhibitor blocked the negative effect of CRH on gonadotrophin synthesis and secretion. Furthermore, our results demonstrated that HSP70 inhibited gonadotrophin synthesis and secretion by blocking GnRH-induced SMAD3 phosphorylation, which acts as the targeting molecule of HSP70, while CRH upregulated HSP70 expression through the PKC and ERK pathways. Collectively, these data demonstrate that HSP70 inhibits pituitary gonadotrophin synthesis and secretion by regulating the CRH signaling pathway and inhibiting SMAD3 phosphorylation, which are important for our understanding the mechanisms of the stress affects domestic animal reproductive functions.