Zonation of metabolic activities within specific structures and cell types is a phenomenon of liver organization and ensures complementarity of variant liver functions like protein production, glucose homeostasis and detoxification. To analyze damage and regeneration of liver tissue in response to a toxic agent, expression of liver specific enzymes was analyzed by in situ hybridization in mouse over a 6 days time course following carbon tetrachloride (CCl4) injection. CCl4 mixed with mineral oil was administered to BALB/c mice by intraperitoneal injection, and mice were sacrificed at different time points post injection. Changes in the expression of albumin (Alb), arginase (Arg1), glutaminase 2 (Gls2), Glutamine synthetase (Gs), glucose-6-phosphatase (G6pc), glycogen synthase 2 (Gys2), Glycerinaldehyd-3-phosphat-Dehydrogenase (Gapdh), Cytochrom p450 2E1 (Cyp2e1) and glucagon receptor (Gcgr) genes in the liver were studied by in situ hybridization and qPCR. We observed significant changes in gene expression of enzymes involved in nitrogen and glucose metabolism and their local distribution following CCl4 injury. We also found that Cyp2e1, the primary metabolizing enzyme for CCl4, was strongly expressed in the pericentral zone during recovery. Furthermore, cells in the damaged area displayed distinct gene expression profiles during the analyzed time course and showed complete recovery with strong albumin production 6 days after CCl4 injection. Our results indicate that despite severe damage, liver cells in the damaged area do not simply die but instead display locally adjusted gene expression supporting damage response and recovery.
Premature infants often experience chronic hypoxia, resulting in cognitive & motor neurodevelopmental handicaps. These sometimes devastating handicaps are thought to be caused by compromised neural precursor cell (NPC) repair/recovery resulting in variable central nervous system (CNS) repair/recovery. We have identified differential responses of two mouse strains (C57BL/6 & CD1) to chronic hypoxia that span the range of responsiveness noted in the premature human population. We previously correlated several CNS tissue and cellular behaviors with the different behavioral parameters manifested by these two strains. In this report, we use unbiased array technology to interrogate the transcriptome of the subventricular zone (SVZ) in these strains. Our results illustrate differences in mRNA expression in the SVZ of both C57BL/6 and CD1 mice following hypoxia as well as differences between C57BL/6 and CD1 SVZ under both normoxic and hypoxic conditions. Differences in expression were found in gene sets associated with Sox10-mediated neural functions that explain, in part, the differential cognitive and motor responsiveness to hypoxic insult. This may shed additional light on our understanding of the variable responses noted in the human premature infant population and facilitate early intervention approaches. Further interrogation of the differentially expressed gene sets will provide a more complete understanding of the differential responses to, and recovery from, hypoxic insult allowing for more informed modeling of the ranges of disease severity observed in the very premature human population.
In 1985, a hepatitis C virus (HCV) outbreak caused by plasmapheresis donation was reported in the Hebei Province, China. However, studies assessing the epidemic features and risk factors of HCV in the general population of Hebei have been limited until now.
The multicenter cluster sampling method was used to collect samples. The participants were interviewed. Relevant information was obtained from the general population using a standardized questionnaire, and association and logistic regression analyses were conducted. Serum samples were taken to test anti-HCV by enzyme immunoassays.
A total of 4562 participants from 11 cities of the Hebei Province were enrolled. The average anti-HCV positive rate was 0.62% (29/4562), which was 1.07% in the rural population, compared with 0.22% in the urban population. The anti-HCV positive rate in the 40–59-year age group was higher than in those aged <40 years. History of blood transfusion and transmission in families were the main risk factors for HCV infection in this area.
The anti-HCV positive rate in Hebei has decreased significantly from that two decades ago. Safety of blood products and health education about HCV still need to be improved.
Although superoxide dismutase (SOD) and malondialdehyde (MDA) affect Delayed Onset Muscle Soreness (DOMS), their effects are unclear in rectus femoris muscles (RFM) of rats with different eccentric exercise programs and time points. The purpose of this study is to investigate the effects of the various eccentric exercise programs at different time points on the SOD mRNA expression and MDA using rat as the animal model.
248 male rats were randomly divided into 4 groups: control group (CTL, n = 8), once-only exercise group (OEG, n = 80), continuous exercise group (CEG, n = 80), and intermittent exercise group (IEG, n = 80). Each exercise group was divided into 10 subgroups that exercised 0.5 h, 6 h, 12 h, 24 h, 48 h, 72 h, 96 h, 120 h, 144 h, or 168 h. Rats were sacrificed and their SOD mRNA expression, and MDA concentrations of skeletal muscle tissue were measured.
The specimen in all eccentric exercise programs showed increased RFM SOD1 mRNA expression levels at 0.5 h (P<0.05), and decreased RFM SOD3 mRNA expression at 0.5 h (P<0.05). The continuous eccentric exercise (CE) significantly enhanced muscle SOD2 mRNA level at 0.5 h (P<0.05). After once-only eccentric exercise (OE), SOD1, SOD2, and SOD3 mRNA expression significantly increased at 96 h, whereas MDA concentrations decreased at 96 h. After CE, the correlation coefficients of SOD1, SOD2, SOD3 mRNA expression levels and MDA concentrations were −0.814, −0.763, −0.845 (all P<0.05) at 12 h.
Regular eccentric exercise, especially CE could enhance SOD1 and SOD2 mRNA expression in acute stage and the SOD2 mRNA expression correlates to MDA concentration in vivo, which may improve the oxidative adaption ability of skeletal muscles.
Transcriptional regulation is essential for any gene expression including microRNA expression. MiR-1-1 and miR-133a-2 are essential microRNAs (miRs) involved in cardiac and skeletal muscle development and diseases. Early studies reveal two regulatory enhancers, an upstream and an intragenic, that direct the miR-1-1 and miR-133a-2 transcripts. In this study, we identify a unique serum response factor (SRF) binding motif within the enhancer through bioinformatic approaches. This motif is evolutionarily conserved and is present in a range of organisms from yeast, flies, to humans. We provide evidence to demonstrate that this regulatory motif is SRF-dependent in vitro by electrophoretic mobility shift assay, luciferase activity assay, and endogenous chromatin immunoprecipitation assay followed by DNA sequence confirmation, and in vivo by transgenic lacZ reporter mouse studies. Importantly, our transgenic mice indicate that this motif is indispensable for the expression of miR1-1/133a-2 in the heart, but not necessary in skeletal muscle, while the enhancer is sufficient for miR1-1/133a-2 gene expression in both tissues. The mutation of the motif alone completely abolishes miR-1-1/133a-2 gene expression in the animal heart, but not in the skeletal muscle. Our findings reveal an additional architecture of regulatory complex directing miR-1-1/133a-1 gene expression, and demonstrate how this intragenic enhancer differentially manages the expression of the two miRs in the heart and skeletal muscle, respectively.
Portal vein tumor thrombus (PVTT) is strongly correlated to a poor prognosis for patients with hepatocellular carcinoma (HCC). In this study, we uncovered a causative link between hepatitis B virus (HBV) infection and development of PVTT. Mechanistically, elevated TGF-β activity, associated with the persistent presence of HBV in the liver tissue, suppresses the expression of microRNA-34a, leading to enhanced production of chemokine CCL22, which recruits regulatory T (Treg) cells to facilitate immune escape. These findings strongly suggest that HBV infection and activity of the TGF-β-miR-34a-CCL22 axis serve as potent etiological factors to predispose HCC patients for the development of PVTT, possibly through the creation of an immune-subversive microenvironment to favor colonization of disseminated HCC cells in the portal venous system.
Thymic positive selection is based on the interactions of T cell antigen receptors (TCRs) with self peptide–major histocompatibility complex (MHC) ligands, but the identity of selecting peptides for MHC class II–restricted TCRs and the functional consequences of this peptide specificity are not clear. Here we identify several endogenous self peptides that positively selected the MHC class II–restricted 5C.C7 TCR. The most potent of these also enhanced mature T cell activation, which supports the hypothesis that one function of positive selection is to produce T cells that can use particular self peptide–MHC complexes for activation and/or homeostasis. We also show that inhibiting the microRNA miR-181a resulted in maturation of T cells that overtly reacted toward these erstwhile positively selecting peptides. Therefore, miR-181a helps to guarantee the clonal deletion of particular moderate-affinity clones by modulating the TCR signaling threshold of thymocytes.
The human brain can anatomically combine task-relevant information from different sensory pathways to form a unified perception; this process is called multisensory integration. The aim of the present study was to test whether the multisensory integration abilities of patients with mild cognitive impairment (MCI) and Alzheimer’s disease (AD) differed from those of normal aged controls (NC). A total of 64 subjects were divided into three groups: NC individuals (n = 24), MCI patients (n = 19), and probable AD patients (n = 21). All of the subjects were asked to perform three separate audiovisual integration tasks and were instructed to press the response key associated with the auditory, visual, or audiovisual stimuli in the three tasks. The accuracy and response time (RT) of each task were measured, and the RTs were analyzed using cumulative distribution functions to observe the audiovisual integration. Our results suggest that the mean RT of patients with AD was significantly longer than those of patients with MCI and NC individuals. Interestingly, we found that patients with both MCI and AD exhibited adequate audiovisual integration, and a greater peak (time bin with the highest percentage of benefit) and broader temporal window (time duration of benefit) of multisensory enhancement were observed. However, the onset time and peak benefit of audiovisual integration in MCI and AD patients occurred significantly later than did those of the NC. This finding indicates that the cognitive functional deficits of patients with MCI and AD contribute to the differences in performance enhancements of audiovisual integration compared with NC.
Alzheimer’s disease; audiovisual integration; cognitive functional deficits; mild cognitive impairment; performance enhancement
Background and aim
Limitations of the currently recommended stepwise treatment pathway for type 2 diabetes mellitus (T2DM), especially the failure of monotherapies to maintain good glycemic control, have prompted use of early, more aggressive combination therapies.
The VISION study is designed to explore the efficacy and safety of vildagliptin as an add-on to metformin therapy compared with up-titration of metformin monotherapy in Chinese patients with T2DM.
VISION, a 24-week, phase 4, prospective, randomized, multicenter, open-label, parallel-group study, will include 3312 Chinese T2DM patients aged ≥18 years who are inadequately controlled (6.5% >HbA1c ≤9%) by metformin (750–1000 mg/day). Eligible patients will be randomized to receive either vildagliptin plus metformin or up-titration of metformin monotherapy (5:1). Patients will also be subgrouped (1:1:1:1) based on their age and body mass index (BMI): <60 years and <24 kg/m2; <60 years and ≥24 kg/m2; ≥60 years and <24 kg/m2; and ≥60 years and ≥24 kg/m2.
The VISION study will test the hypothesis that early use of combination therapy with vildagliptin and metformin will provide good glycemic control and will be better tolerated than up-titration of metformin monotherapy. The study will also correlate these benefits with age and BMI.
VISION study; Vildagliptin; Type 2 diabetes; Study design; DPP-IV inhibitors
An effective immune response to antigen challenge is critically dependent on the size of the effector cell population generated from clonal activation of antigen-specific T cells. The transcription network involved in regulating the size of the effector population, particularly for CD4 helper T cells, is poorly understood. Here we investigate the role of Id2, an inhibitor of E protein transcription factors, in the generation of CD4 effectors. Utilizing a T cell-specific conditional Id2 knock-out mouse model, we show that Id2 is essential for the development of experimental autoimmune encephalomyelitis (EAE). Although antigen-specific and IL-17 producing CD4 T cells are produced in these mice, the activated CD4 T cells form a smaller pool of effector cells in the peripheral lymphoid organs, exhibit reduced proliferation and increased cell death, and are largely absent in the central nervous system. In the absence of Id2, E protein targets, including the pro-apoptotic protein Bim and Suppressor of cytokine signaling 3 (SOCS3), are expressed at higher levels among activated CD4 T cells. This study reveals a critical role of Id2 in the control of effector CD4 T cell population size and the development of a Th17-mediated autoimmune disease.
The Box-Jenkins approach was used to fit an autoregressive integrated moving average (ARIMA) model to the incidence of hemorrhagic fever with renal Syndrome (HFRS) in China during 1986–2009. The ARIMA (0, 1, 1) × (2, 1, 0)12 models fitted exactly with the number of cases during January 1986–December 2009. The fitted model was then used to predict HFRS incidence during 2010, and the number of cases during January–December 2010 fell within the model's confidence interval for the predicted number of cases in 2010. This finding suggests that the ARIMA model fits the fluctuations in HFRS frequency and it can be used for future forecasting when applied to HFRS prevention and control.
Objective. To investigate the relationship between Brachial-ankle pulse wave velocity (baPWV), and its associated risk factors in Chinese patients with RA.
Methods. 138 Chinese RA patients and 150 healthy subjects were included. baPWV of all the participants was measured. RA related factors were determined, as well as traditional cardiovascular risk factors.
Results. baPWV was significant higher in RA group (1705.44 ± 429.20 cm/s) compared to the healthy control group (1386.23 ± 411.09 cm/s) (P < 0.001). Compared with low baPWV group, high baPWV group patients were significantly older (P = 0.008) and taller (P = 0.033). Serum cholesterol (P = 0.035), triglycerides (P = 0.004), and LDL level (P = 0.006) were significantly higher in high baPWV group patients compared with low baPWV group patients. The baPWV of RA patients was positively correlated with age (r = 0.439, P < 0.001), and serum cholesterol level (r = 0.231, P = 0.035), serum triglycerides level (r = 0.293, P < 0.001), serum LDL level (r = 0.323, P = 0.003). Meanwhile, baPWV negatively correlated with the height of RA patients (r = −0.253, P = 0.043). Multivariate regression analysis showed that baPWV of RA group was independently associated with age and serum triglycerides level. Conclusions. The old age and high level of serum triglycerides may be the major determinants of arterial stiffness in Chinese RA patients.
EF-hand proteins are ubiquitous in cell signaling. Parvalbumin (Parv), the archetypal EF-hand protein, is a high-affinity Ca2+ buffer in many biological systems. Given the centrality of Ca2+ signaling in health and disease, EF-hand motifs designed to have new biological activities may have widespread utility. Here, an EF-hand motif substitution that had been presumed to destroy EF-hand function, that of glutamine for glutamate at position 12 of the second cation binding loop domain of Parv (ParvE101Q), markedly inverted relative cation affinities: Mg2+ affinity increased, whereas Ca2+ affinity decreased, forming a new ultra-delayed Ca2+ buffer with favorable properties for promoting cardiac relaxation. In therapeutic testing, expression of ParvE101Q fully reversed the severe myocyte intrinsic contractile defect inherent to expression of native Parv and corrected abnormal myocardial relaxation in diastolic dysfunction disease models in vitro and in vivo. Strategic design of new EF-hand motif domains to modulate intracellular Ca2+ signaling could benefit many biological systems with abnormal Ca2+ handling, including the diseased heart.
Diseases caused by dengue virus (DV) infection vary in severity, with symptoms ranging from mild fever to life threatening dengue hemorrhage fever (DHF) and dengue shock syndrome (DSS). Clinical studies have shown that significant decrease in the level of lipoproteins is correlated with severe illness in DHF/DSS patients. Available evidence also indicates that lipoproteins including high-density lipoprotein (HDL) and low-density lipoprotein (LDL) are able to facilitate cell entry of HCV or other flaviviruses via corresponding lipoprotein receptors. In this study, we found that pre-incubation of DV with human serum leads to an enhanced DV infectivity in various types of cells. Such enhancement could be due to interactions between serum components and DV particles. Through co-immunoprecipitation we revealed that apolipoprotein A-I (ApoA-I), the major protein component in HDL, is associated with DV particles and is able to promote DV infection. Based on that observation, we further found that siRNA knockdown of the scavenger receptor class B type I (SR-BI), the cell receptor of ApoA-I, abolished the activity of ApoA-I in enhancement of DV infection. This suggests that ApoA-I bridges DV particles and cell receptor SR-BI and facilitates entry of DV into cells. FACS analysis of cell surface dengue antigen after virus absorption further confirmed that ApoA-I enhances DV infection via promoting initial attachment of the virus to cells. These findings illustrate a novel entry route of DV into cells, which may provide insights into the functional importance of lipoproteins in dengue pathogenesis.
With the rapid development of urbanization, pregnant population is growing rapidly in Shenzhen, and it has been a difficulty to serve more and more pregnant women and reduce spatial access disparities to maternity units (MUs). Understanding of the current status of accessibility to MUs is valuable for supporting the rational allocation of MUs in the future.
Based on pregnant population data and MUs data, this study uses a two-step floating catchment area (2SFCA) method based on Geographic Information System (GIS) to analyze the current spatial accessibility to MUs, and then make a comparison between that to public MUs and private MUs.
Our analysis of the accessibility to all MUs within a distance of 20 km shows that the accessibilities of the areas alongside the traditional border management line are acceptable, meanwhile highlights some critical areas, such as the west part of Nanshan district and the vast east part of Longgang district. The comparison between spatial accessibility to public MUs and private MUs shows statistically significant difference.
Results of this study suggest a great effort should be made to improve the equity of spatial accessibility to MUs in Shenzhen. For policy-making, strategy for the siting and allocation of future MUs, no matter public or private, should guarantee the greatest spatial accessibility for every pregnant woman.
Published evidence suggests that the rs2233678 (−842 G>C) polymorphism in the PIN1 (peptidyl-prolyl cis/trans somerase NIMA-interacting 1) promoter region may be associated with cancer risk; however, the conclusion is still inconclusive.
We conducted a meta-analysis to determine whether −842 G>C polymorphism was associated with cancer risk. Odds ratio (OR) and 95% confidence intervals (95% CI) were used to assess the strength of association. Genotype distribution data and adjusted ORs were collected to calculate the pooled ORs. Meta-regression was conducted to detect the source of heterogeneity. Publication bias was evaluated by Egger’s test and Begg’s test.
A total of 11 eligible studies, including 9280 participants, were identified and analyzed. Overall, we found that carriers of the −842 C allele were associated with significantly decreased cancer risk (C vs. G, OR = 0.750, 95% CI: 0.639–0.880, Pheterogeneity = 0.014, estimated by genotype distribution data; CC+GC vs. GG, OR = 0.668, 95% CI: 0.594–0.751, Pheterogeneity = 0.638, estimated by adjusted ORs). No evidence of publication bias was observed. Meta-regression revealed that ethnicities (p = 0.021) and sample size (p = 0.02) but not sources of control (p = 0.069) were the source of heterogeneity.
These results suggest that the PIN1 rs2233678 (−842 G>C) polymorphism significantly reduces cancer risk.
The prevalence of type 2 diabetes mellitus (T2DM) is increasing rapidly among Chinese adults, and limited data are available on T2DM management and the status of glycemic control in China. We assessed the efficacy of oral antidiabetes drugs (OADs), glucagon-like peptide-1 (GLP-1) receptor agonists, and insulin for treatment of T2DM across multiple regions in China.
This was a multicenter, cross-sectional survey of outpatients conducted in 606 hospitals across China. Data from all the patients were collected between April and June, 2011.
A total of 238,639 patients were included in the survey. Eligible patients were treated with either OADs alone (n=157,212 [65.88%]), OADs plus insulin (n=80,973 [33.93%]), or OADs plus GLP-1 receptor agonists (n=454 [0.19%]). The OAD monotherapy, OAD + insulin, and OAD + GLP-1 receptor agonist groups had mean glycosylated hemoglobin (HbA1c) levels (±SD) of 7.67% (±1.58%), 8.21% (±1.91%), and 7.80% (±1.76%), respectively. Among those three groups, 34.63%, 26.21%, and 36.12% met the goal of HbA1c <7.0%, respectively. Mean HbA1c and achievement of A1c <7.0% was related to the duration of T2DM.
Less than one third of the patients had achieved the goal of HbA1c <7.0%. Glycemic control decreased and insulin use increased with the duration of diabetes.
China; GLP-1 receptor agonists; HbA1c; Insulin; Oral antidiabetes drugs (OADs); Type 2 diabetes mellitus
This article aims to investigate whether auditory stimuli in the horizontal plane, particularly originating from behind the participant, affect audiovisual integration by using behavioral and event-related potential (ERP) measurements. In this study, visual stimuli were presented directly in front of the participants, auditory stimuli were presented at one location in an equidistant horizontal plane at the front (0°, the fixation point), right (90°), back (180°), or left (270°) of the participants, and audiovisual stimuli that include both visual stimuli and auditory stimuli originating from one of the four locations were simultaneously presented. These stimuli were presented randomly with equal probability; during this time, participants were asked to attend to the visual stimulus and respond promptly only to visual target stimuli (a unimodal visual target stimulus and the visual target of the audiovisual stimulus). A significant facilitation of reaction times and hit rates was obtained following audiovisual stimulation, irrespective of whether the auditory stimuli were presented in the front or back of the participant. However, no significant interactions were found between visual stimuli and auditory stimuli from the right or left. Two main ERP components related to audiovisual integration were found: first, auditory stimuli from the front location produced an ERP reaction over the right temporal area and right occipital area at approximately 160–200 milliseconds; second, auditory stimuli from the back produced a reaction over the parietal and occipital areas at approximately 360–400 milliseconds. Our results confirmed that audiovisual integration was also elicited, even though auditory stimuli were presented behind the participant, but no integration occurred when auditory stimuli were presented in the right or left spaces, suggesting that the human brain might be particularly sensitive to information received from behind than both sides.
Two brothers (case 1 and case 2) with erythema nodosum were diagnosed with thromboangiitis obliterans (TAO). The patients were treated with compounds including Danshen Dripping Pills, Fufang Danshen Diwan and Salvia tetramethylpyrazine. The patients were also treated with fibro-blast growth factor to promote epidermal growth and Bayaspirin enteric-coated tablets to reduce platelet aggregation. The polysaccharide nucleic acid fraction of Bacillus Calmette-Guérin and compound glycyrrhizin tablets were taken to improve immune function. Following treatment, case 2 had reduced pain levels in the left foot. The ulcer on the first toe of the left foot had decreased in size, with a reduction in pus secretions and inflammation. Case 1 demonstrated a reduction in pus secretion from the ulcer. However, the area of the ulcer had increased, spreading to the fifth toe with gangrene. A tendon had become exposed on the right foot, which was broken and induced severe pain.
erythema nodosum; thromboangiitis obliterans; case report
Insulin is known to regulate multiple cellular functions and is used for the treatment of diabetes. MicroRNAs have been demonstrated to be involved in many human diseases, including Type 2 diabetes. In this study, we showed that insulin decreased miR-99a expression levels, but induced glucose consumption and lactate production, and increased the expression of mTOR, HIF-1α and PKM2 in HepG2 and HL7702 cells. Forced expression of miR-99a or rapamycin treatment blocked insulin-induced PKM2 and HIF-1α expression, and glucose consumption and lactate production. Meanwhile, knockdown of HIF-1α inhibited PKM2 expression and insulin-induced glucose consumption. Taken together, these findings will reveal the role and mechanism ofinsulin in regulating glycolytic activities via miR-99a/mTOR.
The tumour stroma is an active participant during cancer progression. Stromal cells promote tumour progression and metastasis through multiple mechanisms including enhancing tumour invasiveness and angiogenesis, and suppressing immune surveillance. We report here that miR-126/miR-126*, a microRNA pair derived from a single precursor, independently suppress the sequential recruitment of mesenchymal stem cells and inflammatory monocytes into the tumour stroma to inhibit lung metastasis by breast tumour cells in a mouse xenograft model. miR-126/miR-126* directly inhibit stromal cell-derived factor-1 alpha (Sdf-1α) expression, and indirectly suppress the expression of chemokine (C–C motif) ligand 2 (Ccl2) by cancer cells in an Sdf-1α-dependent manner. miR-126/miR-126* expression is downregulated in cancer cells by promoter methylation of their host gene Egfl7. These findings determine how this microRNA pair alters the composition of the primary tumour microenvironment to favour breast cancer metastasis, and demonstrate a correlation between miR-126/126* downregulation and poor metastasis-free survival of breast cancer patients.
Ethylenevinyl alcohol copolymer; Onyx copolymer; hemoptysis; bronchial artery embolization
Although a large set of full-length transcripts was recently assembled in catfish, annotation of large gene families, especially those with duplications, is still a great challenge. Most often, complexities in annotation cause mis-identification and thereby much confusion in the scientific literature. As such, detailed phylogenetic analysis and/or orthology analysis are required for annotation of genes involved in gene families. The ATP-binding cassette (ABC) transporter gene superfamily is a large gene family that encodes membrane proteins that transport a diverse set of substrates across membranes, playing important roles in protecting organisms from diverse environment.
In this work, we identified a set of 50 ABC transporters in catfish genome. Phylogenetic analysis allowed their identification and annotation into seven subfamilies, including 9 ABCA genes, 12 ABCB genes, 12 ABCC genes, 5 ABCD genes, 2 ABCE genes, 4 ABCF genes and 6 ABCG genes. Most ABC transporters are conserved among vertebrates, though cases of recent gene duplications and gene losses do exist. Gene duplications in catfish were found for ABCA1, ABCB3, ABCB6, ABCC5, ABCD3, ABCE1, ABCF2 and ABCG2.
The whole set of catfish ABC transporters provide the essential genomic resources for future biochemical, toxicological and physiological studies of ABC drug efflux transporters. The establishment of orthologies should allow functional inferences with the information from model species, though the function of lineage-specific genes can be distinct because of specific living environment with different selection pressure.
The migration of effector or memory T cells to the graft is a critical event in the
rejection of transplanted organs. The prevailing view is that the key steps involved
in T cell migration — integrin-mediated firm adhesion followed by
transendothelial migration — are dependent on the activation of
Gαi-coupled chemokine receptors on T cells. In contrast to
this view, we demonstrated in vivo that cognate antigen was necessary for the firm
adhesion and transendothelial migration of CD8+ effector T cells specific
to graft antigens and that both steps occurred independent of
Gαi signaling. Presentation of cognate antigen by either
graft endothelial cells or bone marrow–derived APCs that extend into the
capillary lumen was sufficient for T cell migration. The adhesion and transmigration
of antigen-nonspecific (bystander) effector T cells, on the other hand, remained
dependent on Gαi, but required the presence of
antigen-specific effector T cells. These findings underscore the primary role of
cognate antigen presented by either endothelial cells or bone
marrow–derived APCs in the migration of T cells across endothelial
barriers and have important implications for the prevention and treatment of graft
BACKGROUND & AIMS
Krüppel-like factor 4 (KLF4) is a putative tumor suppressor gene, however, the functional status and significance of KLF4 in hepatocellular carcinogenesis is unknown. In this study, we sought to determine the clinical significance and underlying mechanisms of its dysregulated signaling and biologic impact.
We have used HCC tissue microarray and molecular biology and animal models to evaluate the activation and function of KLF4-Vitamin D Receptor (VDR) pathway in human HCC.
KLF4 protein expression was decreased or lost in primary HCC and, in particular, lymph node metastases when compared with that in normal liver. Moreover, loss of KLF4 expression in the primary tumors was significantly associated with poor survival, and also a prognostic marker. Consistently, most human HCC cell lines exhibited loss of or a substantial decrease in KLF4 expression. Promoter hypermethylation contributed to the decreased KLF4 expression. Enforced restoration of KLF4 expression resulted in MET, and marked inhibition of cell migration, invasion and growth in vitro, and significantly attenuated tumor growth and metastasis in animal models. Moreover, VDR is a direct transcriptional target of KLF4 and two KLF4-binding sites in the VDR promoter bound specifically to KLF4 protein. Increased VDR expression sensitized the inhibitory effects of Vitamin D on tumor growth.
The novel KLF4-VDR pathway plays a critical role in HCC development and progression and its deregulated signaling could be a promising new molecular target for designing novel preventive and therapeutic strategies to control this malignancy.
VDR; KLF4; liver cancer; progression