Pyruvate Upregulates Hepatic FGF21 Expression by Activating PDE and Inhibiting cAMP-Epac-CREB Signaling Pathway.

Fibroblast growth factor 21 (FGF21) functions as a polypeptide hormone to regulate glucose and lipid metabolism, and its expression is regulated by cellular metabolic stress. Pyruvate is an important intermediate metabolite that acts as a key hub for cellular fuel metabolism. However, the effect of pyruvate on hepatic FGF21 expression and secretion remains unknown. Herein, we examined the gene expression and protein levels of FGF21 in human hepatoma HepG2 cells and mouse AML12 hepatocytes in vitro, as well as in mice in vivo. In HepG2 and AML12 cells, pyruvate at concentrations above 0.1 mM significantly increased FGF21 expression and secretion. The increase in cellular cAMP levels by adenylyl cyclase activation, phosphodiesterase (PDE) inhibition and 8-Bromo-cAMP administration significantly restrained pyruvate-stimulated FGF21 expression. Pyruvate significantly increased PDE activities, reduced cAMP levels and decreased CREB phosphorylation. The inhibition of exchange protein directed activated by cAMP (Epac) and cAMP response element binding protein (CREB) upregulated FGF21 expression, upon which pyruvate no longer increased FGF21 expression. The increase in plasma pyruvate levels in mice induced by the intraperitoneal injection of pyruvate significantly increased FGF21 gene expression and PDE activity with a reduction in cAMP levels and CREB phosphorylation in the mouse liver compared with the control. In conclusion, pyruvate activates PDEs to reduce cAMP and then inhibits the cAMP-Epac-CREB signaling pathway to upregulate FGF21 expression in hepatocytes.

Forecasting seasonal variations in electricity consumption and electricity usage efficiency of industrial sectors using a grey modeling approach.

The aim of this research is to forecast seasonal fluctuations in electricity consumption, and electricity usage efficiency of industrial sectors and identify the impacts of the novel coronavirus disease 2019 (COVID-19). For this purpose, a new seasonal grey prediction model (AWBO-DGGM(1,1)) is proposed: it combines buffer operators and the DGGM(1,1) model. Based on the quarterly data of the industrial enterprises in Zhejiang Province of China from the first quarter of 2013 to the first quarter of 2020, the GM(1,1), DGGM(1,1), SVM, and AWBO-DGGM(1,1) models are employed, respectively, to simulate and forecast seasonal variations in electricity consumption, the added value, and electricity usage efficiency. The results indicate that the AWBO-DGGM(1,1) models can identify seasonal fluctuations and variations in time series data, and predict the impact of COVID-19 on industrial systems. The minimum mean absolute percentage errors (MAPEs) of the electricity consumption, added value, and electricity usage efficiency of industrial enterprises separately are 0.12%, 0.10%, and 3.01% in the training stage, while those in the test stage are 6.79%, 4.09%, and 2.25%, respectively. The electricity consumption, added value, and electricity usage efficiency of industrial enterprises in Zhejiang Province will still present a tendency to grow with seasonal fluctuations from 2020 to 2022. Of them, the added value is predicted to increase the fastest, followed by electricity consumption.

Lipopolysaccharide inhibits GPR120 expression in macrophages via Toll-like receptor 4 and p38 MAPK activation.

Free fatty acid receptor G protein-coupled receptor 120 (GPR120) is highly expressed in macrophages and was reported to inhibit lipopolysaccharide (LPS)-stimulated cytokine expression. Under inflammation, macrophages exhibit striking functional changes, but changes in GPR120 expression and signaling are not known. In this study, the effects of LPS treatment on macrophage GPR120 expression and activation were investigated. The results showed that LPS inhibited GPR120 expression in mouse macrophage cell line Ana-1 cells. Moreover, LPS treatment inhibited GPR120 expression in mouse alveolar macrophages both in vitro and in vivo. The inhibitory effect of LPS on GPR120 expression was blocked by Toll-like receptor 4 (TLR4) inhibitor TAK242 and p38 mitogen-activated protein kinase inhibitor LY222820, but not by ERK1/2 inhibitor U0126 and c-Jun N-terminal kinase inhibitor SP600125. LPS-induced inhibition of GPR120 expression was not attenuated by GPR120 agonists TUG891 and GW9508. TUG891 inhibited the phagocytosis of alveolar macrophages, and LPS treatment counteracted the effects of TUG891 on phagocytosis. These results indicate that pretreatment with LPS inhibits GPR120 expression and activation in macrophages. It is suggested that LPS-induced inhibition of GPR120 expression is a reaction enhancing the LPS-induced pro-inflammatory response of macrophages.

[The molecular mechanism of fibroblast growth factor 21-inhibited leptin expression in adipocytes].

The present study was aimed to clarify the signaling molecular mechanism by which fibroblast growth factor 21 (FGF21) regulates leptin gene expression in adipocytes. Differentiated 3T3-F442A adipocytes were used as study object. The mRNA expression level of leptin was detected by fluorescence quantitative RT-PCR. The phosphorylation levels of proteins of signal transduction pathways were detected by Western blot. The results showed that FGF21 significantly down-regulated the mRNA expression level of leptin in adipocytes, and FGF21 receptor inhibitor BGJ-398 could completely block this effect. FGF21 up-regulated the phosphorylation levels of ERK1/2 and AMPK in adipocytes. Either ERK1/2 inhibitor SCH772984 or AMPK inhibitor Compound C could partially block the inhibitory effect of FGF21, and the combined application of these two inhibitors completely blocked the effect of FGF21. Neither PI3K inhibitor LY294002 nor Akt inhibitor AZD5363 affected the inhibitory effect of FGF21 on leptin gene expression. These results suggest that FGF21 may inhibit leptin gene expression by activating ERK1/2 and AMPK signaling pathways in adipocytes.

[Facilitative glucose transporters: expression, distribution and the relationship to diseases].

Facilitative glucose transporters (GLUT) are proteins that mediate glucose transmembrane transport in the form of facilitated diffusion, which play an important role in regulating cell energy metabolism. There are many breakthroughs in researches of facilitative GLUT in recent years. It has been known that there are 14 subtypes of facilitative GLUT with obvious tissue specificity in distribution and physiological function. In the present review, the tissue and cellular distribution, subcellular localization, expression regulation, physiological function and the relationship to diseases of facilitative GLUT subtypes were summarized, in order to further understand their physiological and pathophysiological significances.

Diagnosis and treatment of rare complications of pelvic fractures.

PURPOSE: To enhance the awareness of rare complications of pelvic fracture and describe the correct diagnosis and effective treatment. METHODS: A total of 188 cases of pelvic fractures were retrospectively reviewed, and four patients who suffered from four types of rare pelvic fracture complications were described, namely ureteral obstruction caused by retroperitoneal hematoma-induced abdominal compartment syndrome (ACS), bowel entrapment, external iliac artery injury, and open scrotal sac injury. RESULTS: We demonstrated that combined measures should be employed to prevent the occurrence of ACS following major pelvic fractures. Ureteral catheter support may be a good option at an early stage when ACS occurred. Contrasted computed tomography examination and sufficient awareness are keys to a correct diagnosis of bowel entrapment following pelvic fractures. Recognition of risk factors, early diagnosis, and prompt treatment of suspected injury of the external iliac artery are keys to patient survival and to avoid limb loss. Scrotal and/or testicular injury complicated by pelvic fractures should be carefully treated to maintain normal gonad function. Additionally, establishment of a sophisticated trauma care system and multi-disciplinary coordination are important for correct diagnosis and treat- ment of rare complications in pelvic fractures. CONCLUSIONS: Rare complications of pelvic fractures are difficult to diagnose and negatively impact outcome. Recognition of risk factors and sufficient awareness are essential for correct diagnosis and prompt treatment.

[Study on method for formulating clinical practice guidelines of common Chinese patent medicines based on clinical practices].

The clinical application of Chinese patent medicines has suffered sever problems and required guidelines for clinical practices. Currently, the expert consensus method is more suitable for formulating clinical practice guidelines of Chinese patent medicines than the evidence-based method. However, there remain problems in the application of the expert consensus method. This study proposed a derivative expert consensus method--a method for formulating clinical practice guidelines of common Chinese patent medicines based on clinical practices, and introduced the method in terms of research thought, methodology and implementation procedure.

Transcutaneous vagus nerve stimulation for the treatment of depression: a study protocol for a double blinded randomized clinical trial.

BACKGROUND: Depressive disorders are the most common form of mental disorders in community and health care settings. Unfortunately, the treatment of Major Depressive Disorder (MDD) is far from satisfactory. Vagus nerve stimulation (VNS) is a relatively new and promising physical treatment for depressive disorders. One particularly appealing element of VNS is the long-term benefit in mood regulation. However, because this intervention involves surgery, perioperative risks, and potentially significant side effects, this treatment has been limited to those patients with treatment-resistant depression who have failed medication trials and exhausted established somatic treatments for major depression, due to intolerance or lack of response.This double-blinded randomized clinical trial aims to overcome these limitations by introducing a novel method of stimulating superficial branches of the vagus nerve on the ear to treat MDD. The rationale is that direct stimulation of the afferent nerve fibers on the ear area with afferent vagus nerve distribution should produce a similar effect as classic VNS in reducing depressive symptoms without the burden of surgical intervention. DESIGN: One hundred twenty cases (60 males) of volunteer patients with mild and moderate depression will be randomly divided into transcutaneous vagus nerve stimulation group (tVNS) and sham tVNS group. The treatment period lasts 4 months and all clinical and physiological measurements are acquired at the beginning and the end of the treatment period. DISCUSSION: This study has the potential to significantly extend the application of VNS treatment for MDD and other disorders (including epilepsy, bipolar disorder, and morbid obesity), resulting in direct benefit to the patients suffering from these highly prevalent disorders. In addition, the results of this double-blinded clinical trial will shed new light on our understanding of acupuncture point specificity, and development of methodologies in clinical trials of acupuncture treatment. TRIALS REGISTRATION: Clinical Trials. ChiCTR-TRC-11001201 http://www.chictr.org/cn/

Free fatty acid receptors in the endocrine regulation of glucose metabolism: Insight from gastrointestinal-pancreatic-adipose interactions.

Glucose metabolism is primarily controlled by pancreatic hormones, with the coordinated assistance of the hormones from gastrointestine and adipose tissue. Studies have unfolded a sophisticated hormonal gastrointestinal-pancreatic-adipose interaction network, which essentially maintains glucose homeostasis in response to the changes in substrates and nutrients. Free fatty acids (FFAs) are the important substrates that are involved in glucose metabolism. FFAs are able to activate the G-protein coupled membrane receptors including GPR40, GPR120, GPR41 and GPR43, which are specifically expressed in pancreatic islet cells, enteroendocrine cells as well as adipocytes. The activation of FFA receptors regulates the secretion of hormones from pancreas, gastrointestine and adipose tissue to influence glucose metabolism. This review presents the effects of the FFA receptors on glucose metabolism via the hormonal gastrointestinal-pancreatic-adipose interactions and the underlying intracellular mechanisms. Furthermore, the development of therapeutic drugs targeting FFA receptors for the treatment of abnormal glucose metabolism such as type 2 diabetes mellitus is summarized.

α-Lipoic acid up-regulates gene expression but reduces protein levels of fibroblast growth factor 21 in HepG2 cells.

Fibroblast growth factor 21 (FGF21) is a metabolism-regulating hepatokine, and its expression is finely controlled by the nutrients and cellular stressors. α-Lipoic acid (ALA) regulates fuel metabolism as a nutrient, but it also arouses mitochondrial and endoplasmic reticulum (ER) stress as well as oxidative stress in hepatocytes. However, the role of cellular stress in ALA-regulated FGF21 expression has not been demonstrated as yet. The present study found that ALA up-regulated FGF21 gene expression while it reduced FGF21 protein levels in HepG2 cells, which was accompanied by mitochondrial damage that was shown by ATP reduction and ROS elevation. ALA led to mitochondrial stress and ER stress as shown by the increased expression of HSP60, ATF6 and ATF4. Inhibition of ER stress by 4-PBA significantly attenuated ALA-stimulated FGF21 gene expression while it did not influence the reduction of FGF21 protein levels. H2 O2 -induced oxidative stress reduced FGF21 protein levels in HepG2 cells, and anti-oxidation by Tempol blocked ALA-induced reduction of FGF21 proteins. In conclusion, ALA up-regulates FGF21 gene expression through the stimulation of mitochondrial and ER stress while it reduces FGF21 protein levels through the induction of oxidative stress in HepG2 cells. Further studies are needed to demonstrate the in vivo effect of ALA on hepatic FGF21 expression.

Comparison of the Curative Efficacy of Hemivertebra Resection via the Posterior Approach Assisted With Unilateral and Bilateral Internal Fixation in the Treatment of Congenital Scoliosis.

Objective: This study aimed to compare the curative efficacy of hemivertebra resection via the posterior approach assisted with unilateral and bilateral internal fixation in the treatment of congenital scoliosis (CS). Methods: In this study, 29 children (15 males and 14 females), who underwent hemivertebra resection via the posterior approach and received internal fixation from November 2005 to September 2018, were analyzed retrospectively. The age of these patients ranged from 0.9 to 15 years, with an average of 3.8 years. The follow-up duration ranged from 2 to 12.3 years, with an average of 5.7 years. The patients in group A received unilateral internal fixation, and those in group B received bilateral internal fixation. The operation duration, bleeding volume, and complications during the operation, as well as the Cobb angles of scoliosis and kyphosis before and after the operation and at the last follow-up, were compared between the two groups. Results: In group A, the operation duration was 207.4 ± 54.5 min, and the bleeding volume was 215.3 ± 75.4 ml; in group B, the operation duration was 249.5 ± 51.0 min, and the bleeding volume was 291.3 ± 115.6 ml (P < 0.05). The Cobb angles of segmental scoliosis, segmental kyphosis, cephalic compensatory curve, and caudal compensatory curve were significantly improved in the two groups after operation and at the last follow-up (P < 0.05). The post-operative correction rate of the scoliosis Cobb angle was 67.2% in group A and 79.5% in group B; and the difference was statistically significant (P < 0.05). At the last follow-up, the correction rate of the scoliosis Cobb angle was 72.7% in group A and 76.2% in group B (P > 0.05). After the operation and at the last follow-up, the correction rates of kyphosis were 83.1 and 79.6% in group A and 71.8 and 65.5% in group B (P > 0.05). Conclusion: Hemivertebra resection via posterior approach with unilateral internal fixation can also achieve the effect of bilateral internal fixation in the treatment of CS. It is able to preserve a certain degree of contralateral spinal growth potential and is a feasible method.

ß-Hydroxybutyrate upregulates FGF21 expression through inhibition of histone deacetylases in hepatocytes.

Fibroblast growth factor 21 (FGF21) is secreted by hepatocytes as a peptide hormone to regulate glucose and lipid metabolism. FGF21 promotes hepatic ketogenesis and increases ketone body utilization in starvation. Histones are the target molecules of nutrients in regulating hepatic metabolic homeostasis. However, the effect of ketone bodies on FGF21 expression and the involvement of histones in it is not clear yet. The present study observed the effects of ß-hydroxybutyrate (ß-OHB), the main physiological ketone body, on FGF21 expression in human hepatoma HepG2 cells in vitro and in mice in vivo, and the role of histone deacetylases (HDACs) in ß-OHB-regulated FGF21 expression was investigated. The results showed that ß-OHB significantly upregulated FGF21 gene expression and increased FGF21 protein levels while it inhibited HDACs' activity in HepG2 cells. HDACs' inhibition by entinostat upregulated FGF21 expression and eliminated ß-OHB-stimulated FGF21 expression in HepG2 cells. Intraperitoneal injections of ß-OHB in mice resulted in the elevation of serum ß-OHB and the inhibition of hepatic HDACs' activity. Meanwhile, hepatic FGF21 expression and serum FGF21 levels were significantly increased in ß-OHB-treated mice compared with the control. It is suggested that ß-OHB upregulates FGF21 expression through inhibition of HDACs' activity in hepatocytes.

Nano-realgar suppresses lung cancer stem cell growth by repressing metabolic reprogramming.

BACKGROUND: Recent studies in cancer biology suggest that metabolic glucose reprogramming is a potential target for cancer treatment. However, little is known about drug intervention in the glucose metabolism of cancer stem cells (CSCs) and its related underlying mechanisms. METHODS: The crude realgar powder was Nano-grinded to meets the requirements of Nano-pharmaceutical preparations, and Nano-realgar solution (NRS) was prepared for subsequent experiments. Isolation and characterization of lung cancer stem cells (LCSCs) was performed by magnetic cell sorting (MACS) and immunocytochemistry, respectively. Cell viability and intracellular glucose concentration were detected by MTT assay and glucose oxidase (GOD) kit. Protein expressions related to metabolic reprogramming was detected by ELISA assay. Determination of the expression of HIF-1α and PI3K/Akt/mTOR pathways was carried out by RT-PCR and western blotting analysis. A subcutaneous tumor model in BALB/c-nu mice was successfully established to evaluate the effects of Nano-realgar on tumor growth and histological structure, and the expression of HIF-1α in tumor tissues was measured by immunofluorescence. RESULTS: Nano-realgar inhibits cell viability and induces glucose metabolism in LCSCs, and inhibits protein expression related to metabolic reprogramming in a time- and dose-dependent manner. Nano-realgar downregulated the expression of HIF-1α and PI3K/Akt/mTOR pathways in vitro and in vivo. Nano-realgar inhibits tumor growth and changes the histological structure of tumors through in vivo experiments and consequently inhibits the constitutive activation of HIF-1α signaling. CONCLUSIONS: These results reveal that Nano-realgar inhibits tumor growth in vitro and in vivo by repressing metabolic reprogramming. This inhibitory effect potentially related to the downregulation HIF-1α expression via PI3K/Akt/mTOR pathway.

DSCR1/RCAN1 regulates vesicle exocytosis and fusion pore kinetics: implications for Down syndrome and Alzheimer's disease.

Genes located on chromosome 21, over-expressed in Down syndrome (DS) and Alzheimer's disease (AD) and which regulate vesicle trafficking, are strong candidates for involvement in AD neuropathology. Regulator of calcineurin activity 1 (RCAN1) is one such gene. We have generated mutant mice in which RCAN1 is either over-expressed (RCAN1(ox)) or ablated (Rcan1-/-) and examined whether exocytosis from chromaffin cells, a classic cellular model of neuronal exocytosis, is altered using carbon fibre amperometry. We find that Rcan1 regulates the number of vesicles undergoing exocytosis and the speed at which the vesicle fusion pore opens and closes. Cells from both Rcan1-/- and RCAN1(ox) mice display reduced levels of exocytosis. Changes in single-vesicle fusion kinetics are also evident resulting in the less catecholamine released per vesicle with increasing Rcan1 expression. Acute calcineurin inhibition did not replicate the effect of RCAN1 overexpression. These changes are not due to alterations in Ca2+ entry or the readily releasable vesicle pool size. Thus, we illustrate a novel regulator of vesicle exocytosis, Rcan1, which influences both exocytotic rate and vesicle fusion kinetics. If Rcan1 functions similarly in neurons then overexpression of this protein, as occurs in DS and AD brains, will reduce both the number of synaptic vesicles undergoing exocytosis and the amount of neurotransmitter released per fusion event. This has direct implications for the pathogenesis of these diseases as sufficient levels of neurotransmission are required for synaptic maintenance and the prevention of neurodegeneration and vesicle trafficking defects are the earliest hallmark of AD neuropathology.

Protective effects of vasonatrin peptide against hypobaric hypoxia-induced pulmonary hypertension in rats.

1. The aim of the present study was to investigate the in vivo effects of vasonatrin peptide (VNP) on hypoxia-induced pulmonary hypertension (HPH). 2. The HPH model was developed by subjecting rats to hypobaric hypoxia. The HPH rats were then treated with either VNP (50 microg/kg per day, i.p.) or saline (0.5 mL, i.p.) every day for 7 days. Haemodynamic indices, right ventricular hypertrophy (RVH) and remodelling of the pulmonary arteries were evaluated. In addition, plasma levels of atrial natriuretic peptide (ANP), endothelin (ET)-1 and angiotensin II (AngII) were determined, as was natriuretic peptide receptor-C (NPR-C) mRNA expression in the right ventricle. 3. Hypobaric hypoxia induced severe HPH compared with the normoxic control group. Treatment of HPH rats with VNP for 1 week significantly reduced mean pulmonary arterial pressure, pulmonary vascular resistance, RVH and muscularization of the pulmonary arteries, although pulmonary blood flow was increased in this group. In addition, significantly lower levels of plasma ET-1 and AngII and cardiac NPR-C mRNA expression were observed in VNP-treated compared with saline-treated HPH rats, whereas higher plasma concentrations of ANP were found in the former group. Acute intravenous administration of 50 microg/kg VNP significantly ameliorated pulmonary haemodynamics in HPH rats. 4. Taken together, the date indicate that VNP has certain preventative and therapeutic effects against HPH.

Comparison of interface contact profiles of a new minimum contact locking compression plate and the limited contact dynamic compression plate.

In this study, we investigated whether or not a new minimum contact locking compression plate (MC-LCP) can provide advantages over the limited contact dynamic compression plate (LC-DCP) in the context of interface contact area and force. Six matched pairs of cadaveric bones were used for each of three bone types of the humerus, radius and ulna. For each bone type, one of two bone plates was fixed to either of two matched cadaveric bones at the middle of the diaphysis. The interface contact area and force of the plate fixed to three types of human cadaveric bones were evaluated using Fuji prescale pressure sensitive film. Data were quantitated using computer-assisted image analysis. Results showed that the average force between the MC-LCP and humerus or radius was about half of that of the LC-DCP. And the average force between the MC-LCP and ulna was one third less than that of the LC-DCP. Meanwhile, the interface contact area between the MC-LCP and humerus or radius was also about half of that of the LC-DCP, and the interface contact area between the MC-LCP and ulna was less than one third of that of the LC-DCP. These results indicate that the MC-LCP has lower interface contact area and lower average force than that of the LC-DCP. Thus, the MC-LCP system may be a good alternate to treat forearm diaphyseal fractures.

[Effects of linoleic acid on intracellular calcium concentration in primarily cultured rat pancreatic ß-cells and underlying mechanism].

In this study, we investigated the mechanism of linoleic acid-stimulated increase in intracellular calcium concentration ([Ca(2+)](i)) in pancreatic islet ß-cells. Pancreatic islet cells were primarily isolated from rats and cultured for the experiments. The cells were loaded with Fluo-3/AM, the indicator of [Ca(2+)](i), and the intensity of Fluo-3 was measured using confocal microscope. The islet ß-cells were identified by immunocytochemical staining with insulin antibody after recording. The drugs were given by perfusion system. The results showed that linoleic acid (20 µmol/L) stimulated [Ca(2+)](i) increase with the first peak increase and the following plateau increase. Linoleic acid-stimulated [Ca(2+)](i) increase was partly inhibited by removal of extracellular calcium and by transient receptor potential (TRP) channel blocker, La(3+), and it was totally blocked by exhaustion of intracellular calcium stores and inhibition of phospholipase C. It is concluded that linoleic acid stimulates [Ca(2+)](i) increase in islet ß-cells through both extracellular calcium influx via TRP channels and calcium release from intracellular calcium stores.

Interface contact profiles of a novel locking plate and its effect on fracture healing in goat.

OBJECTIVE: To evaluate the interface characteristics of the new-designed locking plate (LP) and limited contact-dynamic compression plate (LC-DCP) and compare the fracture healing between LP and LC-DCP in a goat tibia fracture model. METHODS: Eight-hole LP and LC-DCP were applied to fix fresh goat tibiae in a reproducible manner. The average pressure, force and interface contact area were calculated using Fuji prescale pressure sensitive film interposed among the plate and the bone and image analysis system. Eight-hole LP and LC-DCP were applied to each tibia in a goat tibia fracture model. The fracture healing was evaluated by X-ray photography at postoperative 8 weeks. The goats were sacrificed at postoperative 12 weeks. Three-point bending test was conducted in the tibiae. RESULTS: The interface contact of LP system was smaller than that of LC-DCP (P < 0.05), while interface contact force of LP system was higher than that of LC-DCP (P < 0.05). Radiographs revealed that the fracture line disappeared in the LP group, while the fracture line was visible in DCP group at postoperative 8 weeks. At postoperative 12 weeks, the bending strength and bending load of fractured tibia were higher in LP group than in DCP group, respectively. CONCLUSION: The new-designed locking plate can significantly decrease the contact area on the bone interface, which further provides better fracture healing than conventional plates.

[Determination of GATA-4 in the testis of the mouse].

OBJECTIVE: To explore the characteristics and distribution of GATA-4 in the testis of male mice. METHODS: Paraffin sections were obtained from the testes of 24 male B6SJLF1/J mice, aged 0 day (n = 6), 2 weeks (n = 6), 4 weeks (n = 6) and 6 weeks (n = 6), and the expressions of GATA-4 in the testis were observed by the immunohistochemical ABC method and DAB visualization at different times. RESULTS: Positive expressions of GATA4 were found in the Sertoli cells and Leydig cells of all the mice, but significantly higher in the 4- and 6-week-old than in the 0-day and 2-week-old groups (P < 0.01). And they were also observed in the germ cells of the 4- and 6-week-old mice, significantly higher in the latter than in the former (P < 0.01). CONCLUSION: GATA-4 exists in the testis of male mice, which has provided a morphological base for sex determination and differentiation and hormone regulation in the testis.

Prediction of the Number of Patients Infected with COVID-19 Based on Rolling Grey Verhulst Models.

The outbreak of a novel coronavirus (SARS-CoV-2) has caused a large number of residents in China to be infected with a highly contagious pneumonia recently. Despite active control measures taken by the Chinese government, the number of infected patients is still increasing day by day. At present, the changing trend of the epidemic is attracting the attention of everyone. Based on data from 21 January to 20 February 2020, six rolling grey Verhulst models were built using 7-, 8- and 9-day data sequences to predict the daily growth trend of the number of patients confirmed with COVID-19 infection in China. The results show that these six models consistently predict the S-shaped change characteristics of the cumulative number of confirmed patients, and the daily growth decreased day by day after 4 February. The predicted results obtained by different models are very approximate, with very high prediction accuracy. In the training stage, the maximum and minimum mean absolute percentage errors (MAPEs) are 4.74% and 1.80%, respectively; in the testing stage, the maximum and minimum MAPEs are 4.72% and 1.65%, respectively. This indicates that the predicted results show high robustness. If the number of clinically diagnosed cases in Wuhan City, Hubei Province, China, where COVID-19 was first detected, is not counted from 12 February, the cumulative number of confirmed COVID-19 cases in China will reach a maximum of 60,364-61,327 during 17-22 March; otherwise, the cumulative number of confirmed cases in China will be 78,817-79,780.