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1.  TLR3 deficiency impairs spinal cord synaptic transmission, central sensitization, and pruritus in mice 
The Journal of Clinical Investigation  2012;122(6):2195-2207.
Itch, also known as pruritus, is a common, intractable symptom of several skin diseases, such as atopic dermatitis and xerosis. TLRs mediate innate immunity and regulate neuropathic pain, but their roles in pruritus are elusive. Here, we report that scratching behaviors induced by histamine-dependent and -independent pruritogens are markedly reduced in mice lacking the Tlr3 gene. TLR3 is expressed mainly by small-sized primary sensory neurons in dorsal root ganglions (DRGs) that coexpress the itch signaling pathway components transient receptor potential subtype V1 and gastrin-releasing peptide. Notably, we found that treatment with a TLR3 agonist induces inward currents and action potentials in DRG neurons and elicited scratching in WT mice but not Tlr3–/– mice. Furthermore, excitatory synaptic transmission in spinal cord slices and long-term potentiation in the intact spinal cord were impaired in Tlr3–/– mice but not Tlr7–/– mice. Consequently, central sensitization–driven pain hypersensitivity, but not acute pain, was impaired in Tlr3–/– mice. In addition, TLR3 knockdown in DRGs also attenuated pruritus in WT mice. Finally, chronic itch in a dry skin condition was substantially reduced in Tlr3–/– mice. Our findings demonstrate a critical role of TLR3 in regulating sensory neuronal excitability, spinal cord synaptic transmission, and central sensitization. TLR3 may serve as a new target for developing anti-itch treatment.
PMCID: PMC3366391  PMID: 22565312
2.  Association of Uric Acid with Metabolic Syndrome in Men, Premenopausal Women and Postmenopausal Women 
Objective: To explore the relationship between serum uric acid (SUA) and metabolic syndrome (MS) in men, premenopausal women and postmenopausal women. Methods: A cross-sectional study was conducted in 1,834 community-based Southern Chinese participants from June to October 2012. Sex-specific SUA quartiles were used as follows: <345, 345–<400, 400–<468, ≥468 µmol/L in males; and <248, 248–<288, 288–<328, ≥328 µmol/L in females. MS was defined by the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) Criteria. The association between SUA and MS was then analyzed using the STATA software. Results: The odds ratio (OR) for having MS in the highest versus lowest quartiles of SUA levels was 2.46 (95% confidence interval [CI], 1.39 to 4.34, p = 0.002) in men after adjusting for age, sex, history of coronary heart disease, history of stroke, current current smoking, current alcohol use, physical inactivity, education status, and BMI. Further adjusting for above confounders, hypertension and diabetes, the OR for having MS in the highest versus lowest quartiles of SUA was 3.06 (95% CI, 1.64 to 5.70, p < 0.001). The OR for having MS in the highest versus lowest quartiles of SUA was 3.45 (95% CI, 1.38 to 8.64, p = 0.008) and 1.98 (95% CI, 1.16 to 3.37, p = 0.08) in premenopausal women and postmenopausal women after adjusting for age, sex, history of coronary heart disease, history of stroke, current smoking, current alcohol use, physical inactivity, education status, and BMI. Further adjusting for above confounders, hypertension and diabetes, the OR for having MS in the highest versus lowest quartiles of SUA was 3.42 (95% CI, 1.15 to 10.18, p = 0.03) and 1.87 (95% CI, 1.05 to 3.33, p = 0.03) in premenopausal women and postmenopausal women. Conclusions: Higher SUA levels are positively associated with the presence of MS in males and females. Higher SUA levels had a higher risk of having MS in premenopausal women than in postmenopausal women.
PMCID: PMC3987011  PMID: 24619122
uric acid; metabolic syndrome; premenopausal women and postmenopausal women
3.  Association between Metabolic Syndrome and Chronic Kidney Disease in Perimenopausal Women 
The purpose of the study was to explore the association between metabolic syndrome (MetS) and chronic kidney disease (CKD) in perimenopausal women. A cross-sectional study was conducted in Zhuhai from June to October 2012. Perimenopausal women (n = 685) were included in the study. All participants were divided into three subgroups: Group 1, 40 years old ≤ Age < 50 years old; Group 2, 50 years old ≤ Age < 60 years old; Group 3, 60 years old ≤ Age ≤ 65 years old. MetS was associated with CKD (p < 0.01) in the unadjusted analyses in total subjects. After adjusting the potential confounders, the odd ratios of CKD for MetS was 2.66 (95% CI 1.56 to 4.49, p < 0.001). There was no relationship between MetS and CKD in both Group 1 and Group 3. MetS was associated with CKD (p < 0.001) in the unadjusted analyses in Group 2. After adjusting for potential confounders, MetS was significantly associated with CKD. The odd ratios for MetS was 6.79 (95% CI 2.30 to 20.09, p < 0.001). There was no relationship between elevated blood pressure, elevated fasting glucose, abdominal obesity, Low HDL cholesterol, elevated triglycerides and CKD in both Group 1 and Group 3. Elevated blood pressure was associated with CKD in Group 2 (unadjusted Odds ratio: 4.52 (1.28–16.02), p = 0.02). After adjusting for potential confounders, there was no relationship between elevated blood pressure and CKD (p = 0.78). Elevated fasting glucose was associated with CKD in Group 2 (unadjusted Odds ratio: 3.69 (1.10–12.38), p = 0.03). After adjusting for potential confounders, there was no relationship between elevated fasting glucose and CKD (p = 0.15). There was no relationship between abdominal obesity, Low HDL cholesterol, elevated triglycerides and CKD in Group 2. These findings suggest that in perimenopausal women aged from 50 or older to 60 MetS was associated with CKD. There is no relationship between MetS and CKD in perimenopausal women aged from 40 or older to 50 and aged from 60 or older to 65.
PMCID: PMC3799514  PMID: 23999547
metabolic syndrome; chronic kidney disease; perimenopausal women
4.  Laser-Machined Microcavities for Simultaneous Measurement of High-Temperature and High-Pressure 
Sensors (Basel, Switzerland)  2014;14(8):14330-14338.
Laser-machined microcavities for simultaneous measurement of high-temperature and high-pressure are demonstrated. These two cascaded microcavities are an air cavity and a composite cavity including a section of fiber and an air cavity. They are both placed into a pressure chamber inside a furnace to perform simultaneous pressure and high-temperature tests. The thermal and pressure coefficients of the short air cavity are ∼0.0779 nm/°C and ∼1.14 nm/MPa, respectively. The thermal and pressure coefficients of the composite cavity are ∼32.3 nm/°C and ∼24.4 nm/MPa, respectively. The sensor could be used to separate temperature and pressure due to their different thermal and pressure coefficients. The excellent feature of such a sensor head is that it can withstand high temperatures of up to 400 °C and achieve precise measurement of high-pressure under high temperature conditions.
PMCID: PMC4178988  PMID: 25106018
high pressure sensing; high temperature sensing; laser micromachining; micro-cavity; simultaneous measurement
5.  Comparative studies of salinomycin-loaded nanoparticles prepared by nanoprecipitation and single emulsion method 
Nanoscale Research Letters  2014;9(1):351.
To establish a satisfactory delivery system for the delivery of salinomycin (Sal), a novel, selective cancer stem cell inhibitor with prominent toxicity, gelatinase-responsive core-shell nanoparticles (NPs), were prepared by nanoprecipitation method (NR-NPs) and single emulsion method (SE-NPs). The gelatinase-responsive copolymer was prepared by carboxylation and double amination method. We studied the stability of NPs prepared by nanoprecipitation method with different proportions of F68 in aqueous phase to determine the best proportion used in our study. Then, the NPs were prepared by nanoprecipitation method with the best proportion of F68 and single emulsion method, and their physiochemical traits including morphology, particle size, zeta potential, drug loading content, stability, and in vitro release profiles were studied. The SE-NPs showed significant differences in particle size, drug loading content, stability, and in vitro release profiles compared to NR-NPs. The SE-NPs presented higher drug entrapment efficiency and superior stability than the NR-NPs. The drug release rate of SE-NPs was more sustainable than that of the NR-NPs, and in vivo experiment indicated that NPs could prominently reduce the toxicity of Sal. Our study demonstrates that the SE-NPs could be a satisfactory method for the preparation of gelatinase-responsive NPs for intelligent delivery of Sal.
PMCID: PMC4134115  PMID: 25147486
Salinomycin; Nanoprecipitation method; Single emulsion method; Gelatinase; Drug delivery; Nanoparticles
6.  Tick-borne pathogens and associated co-infections in ticks collected from domestic animals in central China 
Parasites & Vectors  2014;7:237.
Ticks can transmit a number of pathogens to humans and domestic animals. Tick borne diseases (TBDs), which may lead to organ failure and death have been recently reported in China. 98.75% of the total cases (>1000) in Henan provinces have been reported in Xinyang city. Therefore, the aims of this study were to investigate the fauna of ticks and detect the potential pathogens in ticks in Xinyang, the region of central China.
Ticks were collected from 10 villages of Xinyang from April to December 2012, from domestic animals including sheep, cattle and dogs. Then identification of ticks and detection of tick-borne pathogens, including Babesia spp., Theileria spp., Anaplasma spp., Ehrlichia spp., Rickettsia spp., tick-borne encephalitis virus (TBEV), Borrelia burgdorferi sensu lato, Leishmania infantum, were undertaken by using polymerase chain reaction assay (PCR) and sequence analysis. Moreover, the co-infection patterns of various pathogens were compared among locations where ticks were collected.
A total of 308 ticks were collected. Two species of Ixodidae were found, namely Haemaphysalis longicornis (96.75%) and Rhipicephalus microplus (3.25%). Five genera of pathogens, namely Theileria spp. (3.25%), Anaplasma spp. (2.92%), Babesia spp. (1.95%), Ehrlichia spp. (2.92%) and Rickettsia spp. (0.65%), were detected in 7 villages. Co-infections by two pathogens were diagnosed in 11.11% of all infected ticks.
Both human and animal pathogens were abundant in ticks in the study areas. Humans and animals in these regions were at a high risk of exposure to piroplasmosis, since piroplasm had the highest rates of infection and co-infection in positive ticks.
PMCID: PMC4045914  PMID: 24886497
Ticks; Domestic animals; Tick-borne pathogens; Co-infections; China
7.  Enhancement of radiotherapy efficacy by miR-200c-loaded gelatinase-stimuli PEG-Pep-PCL nanoparticles in gastric cancer cells 
Radiotherapy is the main locoregional control modality for many types of unresectable tumors, including gastric cancer. However, many patients fail radiotherapy due to intrinsic radioresistance of cancer cells, which has been found to be strongly associated with cancer stem cell (CSC)-like properties. In this study, we developed a nanoparticle formulation to deliver miR-200c, which is reported to inhibit CSC-like properties, and then evaluated its potential activity as a radiosensitizer. miR-200c nanoparticles significantly augmented radiosensitivity in three gastric cancer cell lines (sensitization enhancement ratio 1.13–1.25), but only slightly in GES-1 cells (1.06). In addition to radioenhancement, miR-200c nanoparticles reduced the expression of CD44, a putative CSC marker, and the percentage of CD44+ BGC823 cells. Meanwhile, other CSC-like properties, including invasiveness and resistance to apoptosis, could be suppressed by miR-200c nanoparticles. CSC-associated radioresistance mechanisms, involving reactive oxygen species levels and DNA repair capacity, were also attenuated. We have demonstrated that miR-200c nanoparticles are an effective radiosensitizer in gastric cancer cells and induce little radiosensitization in normal cells, which suggests that they are as a promising candidate for further preclinical and clinical evaluation.
PMCID: PMC4026568  PMID: 24872697
radiosensitizer; miR-200c; gelatinase-stimuli nanoparticles; cancer stem cell-like properties; gastric cancer
8.  Hypertriglyceridemic Waist Phenotype and Chronic Kidney Disease in a Chinese Population Aged 40 Years and Older 
PLoS ONE  2014;9(3):e92322.
To examine the relationship between the HW phenotype and risk for CKD in a community population aged 40 years and older.
A cross-sectional study was conducted in Zhuhai from June to October 2012. The participants were divided into three groups: Group 1, Waist circumference >90 cm in men or >85 cm in women and triglycerides ≥2 mmol/l; Group 3, Waist circumference ≤90 cm in men or ≤85 cm in women and triglycerides <2 mmol/l; Group 2, The remaining participants. The prevalence of the three subgroups and CKD were determined. The association between HW phenotype and CKD was then analyzed using SPSS (version 13.0).
After adjusting for age and sex, Group 1 was associated with CKD (OR 3.08, 95% CI 2.01, 4.73, P<0.001), when compared with Group 3. Further adjustment for factors which were potential confounders and unlikely to be in the causal pathway between the HW phenotype and CKD, Group 1 was still significantly associated with CKD. The OR for CKD was 2.65 (95% CI 1.65, 4.26, P<0.001). When adjusted for diabetes and hypertension, the association of Group 1 and CKD was still significant (OR 2.09, 95% CI 1.26, 3.45, P = 0.004). Group 2 was associated with CKD (OR 1.81, 95% CI 1.29, 2.53, P = 0.001), when compared with Group 3. Further adjustment for factors which were potential confounders, Group 2 was still significantly associated with CKD. The OR for CKD was 1.75 (95% CI 1.22, 2.51, P = 0.002). When adjusted for diabetes and hypertension, the association between Group 2 and CKD still existed. The OR for CKD was 1.48 (95% CI 1.01, 2.16, P = 0.046).
Our results showed that HW phenotype was associated with CKD in the population aged 40 years and older.
PMCID: PMC3963886  PMID: 24663403
9.  Intelligently Targeted Drug Delivery and Enhanced Antitumor Effect by Gelatinase-Responsive Nanoparticles 
PLoS ONE  2013;8(7):e69643.
The matrix metalloproteinase (MMP) 2/9, also known as collagenases IV and gelatinases A/B, play a key role in cancer invasion and metastasis. However, the clinical trials of the MMP inhibitors (MMPIs) ended up with disappointing results. In this paper, we synthesized a gelatinase-responsive copolymer (mPEG-PCL) by inserting a gelatinase cleavable peptide (PVGLIG) between mPEG and PCL blocks of mPEG-PCL for anticancer drug delivery to make use of MMP2/9 as an intelligent target for drug delivery.
Materials and Methods
mPEG-pep-PCL copolymer was synthesized via ring-opening copolymerization and double-amidation. To evaluate whether Nanoparticles (NPs) prepared from this copolymer are superior to NPs prepared from mPEG-PCL, NPs prepared from mPEG-PCL copolymer were used as positive control. Docetaxel-loading NPs using mPEG-pep-PCL and mPEG-PCL were prepared by nano-precipitation method, mentioned as Gel-NPs and Con-NPs, respectively. The morphologic changes of the NPs after treatment with gelatinases were observed macroscopically by spectrophotometer and microscopically by transmission electron microscopy (TEM) and atomic force microscopy (AFM). The cellular uptake amount and cytotoxicity of Gel-NPs and Con-NPs, respectively, in cell lines with different levels of gelatinase expression were studied. Moreover, the cytotoxicity study on the primary cancer cells isolated from pericardial fluids from a patient with late-stage lung cancer was conducted.
The Gel-NPs aggregated in response to gelatinases, which was confirmed macroscopically and microscopically. The cellular uptake amount of Gel-NPs was correlated with the level of gelatinases. The in vitro antitumor effect of Gel-NPs was also correlated with the level of gelatinases and was superior to Taxotere (commercially available docetaxel) as well as the Con-NPs. The cytotoxicity study on the primary lung cancer cells also confirmed the effectiveness of Gel-NPs.
The results in this study preliminarily demonstrated the effectiveness of gelatinase-responsive targeting strategy and the prospect of this intelligent nano-drug delivery system though further studies are needed.
PMCID: PMC3728361  PMID: 23936062
10.  Lentiviral Transgenic MicroRNA-Based shRNA Suppressed Mouse Cytochromosome P450 3A (CYP3A) Expression in a Dose-Dependent and Inheritable Manner 
PLoS ONE  2012;7(1):e30560.
Cytochomosome P450 enzymes (CYP) are heme-containing monooxygenases responsible for oxidative metabolism of many exogenous and endogenous compounds including drugs. The species difference of CYP limits the extent to which data obtained from animals can be translated to humans in pharmacodynamics or pharmacokinetics studies. Transgenic expression of human CYP in animals lacking or with largely reduced endogenous CYP counterparts is recognized as an ideal strategy to correct CYP species difference. CYP3A is the most abundant CYP subfamily both in human and mammals. In this study, we designed a microRNA-based shRNA (miR-shRNA) simultaneously targeting four members of mouse CYP3A subfamily (CYP3A11, CYP3A16, CYP3A41 and CYP3A44), and transgenic mice expressing the designed miR-shRNA were generated by lentiviral transgenesis. Results showed that the CYP3A expression level in transgenic mice was markedly reduced compared to that in wild type or unrelated miR-shRNA transgenic mice, and was inversely correlated to the miR-shRNA expression level. The CYP3A expression levels in transgenic offspring of different generations were also remarkably lower compared to those of controls, and moreover the inhibition rate of CYP3A expression remained comparable over generations. The ratio of the targeted CYP3A transcriptional levels was comparable between knockdown and control mice of the same gender as detected by RT-PCR DGGE analysis. These data suggested that transgenic miR-shRNA suppressed CYP3A expression in a dose-dependent and inheritable manner, and transcriptional levels of the targeted CYP3As were suppressed to a similar extent. The observed knockdown efficacy was further confirmed by enzymatic activity analysis, and data showed that CYP3A activities in transgenic mice were markedly reduced compared to those in wild-type or unrelated miR-shRNA transgenic controls (1.11±0.71 vs 5.85±1.74, 5.9±2.4; P<0.01). This work laid down a foundation to further knock down the remaining murine CYP3As or CYPs of other subfamilies, and a basis to generate CYP knockdown animals of other species.
PMCID: PMC3265487  PMID: 22291988
11.  Gelatinase-stimuli strategy enhances the tumor delivery and therapeutic efficacy of docetaxel-loaded poly(ethylene glycol)-poly(ɛ-caprolactone) nanoparticles 
Nanoscale drug carriers have been extensively developed to improve drug therapeutic efficiency. However, delivery of chemotherapeutic agents to tumor tissues and cells has not been favorably managed. In this study, we developed a novel “intelligent” nanoparticle, consisting of a gelatinase-cleavage peptide with poly(ethylene glycol) (PEG) and poly(ɛ-caprolactone) (PCL)-based structure for tumor-targeted docetaxel delivery (DOC-TNPs). The docetaxel-loaded PEG-PCL nanoparticles (DOC-NPs) that did not display gelatinase-stimuli behaviors were used as a control. We found clear evidence that the DOC-TNPs were transformed by gelatinases, allowing drug release and enhancing the cellular uptake of DOC (P < 0.01). In vivo biodistribution study demonstrated that targeted DOC-TNPs could accumulate and remain in the tumor regions, whereas non-targeted DOC-NPs rapidly eliminated from the tumor tissues. DOC-TNPs exhibited higher tumor growth suppression than commercialized Taxotere® (docetaxel; Jiangsu Hengrui Medicine Company, Jiangsu, China) and DOC-NPs on hepatic H22 tumor model via intravenous administration (P < 0.01). Both in vitro and in vivo experiments suggest that the gelatinase-mediated nanoscale delivery system is promising for improvement of antitumor efficacy in various overexpressed gelatinase cancers.
PMCID: PMC3265997  PMID: 22287839
drug delivery; stimuli-responsive; gelatinase; antitumor; docetaxel
12.  Reversion of pH-Induced Physiological Drug Resistance: A Novel Function of Copolymeric Nanoparticles 
PLoS ONE  2011;6(9):e24172.
The extracellular pH of cancer cells is lower than the intracellular pH. Weakly basic anticancer drugs will be protonated extracellularly and display a decreased intracellular concentration. In this study, we show that copolymeric nanoparticles (NPs) are able to overcome this “pH-induced physiological drug resistance” (PIPDR) by delivering drugs to the cancer cells via endocytosis rather than passive diffussion.
Materials and Methods
As a model nanoparticle, Tetradrine (Tet, Pka 7.80) was incorporated into mPEG-PCL. The effectiveness of free Tet and Tet-NPs were compared at different extracellular pHs (pH values 6.8 and 7.4, respectively) by MTT assay, morphological observation and apoptotic analysis in vitro and on a murine model by tumor volume measurement, PET-CT scanning and side effect evaluation in vivo.
The cytotoxicity of free Tet decreased prominently (P<0.05) when the extracellular pH decreased from 7.4 to 6.8. Meanwhile, the cytotoxicity of Tet-NPs was not significantly influenced by reduced pH. In vivo experiment also revealed that Tet-NPs reversed PIPDR more effectively than other existing methods and with much less side effects.
The reversion of PIPDR is a new discovered mechanism of copolymeric NPs. This study emphasized the importance of cancer microenvironmental factors in anticancer drug resistance and revealed the superiority of nanoscale drug carrier from a different aspect.
PMCID: PMC3180282  PMID: 21966359
13.  Expression of cadherin10, a type II classic cadherin gene, in the nervous system of the embryonic zebrafish 
Gene expression patterns : GEP  2006;6(7):703-710.
Cadherins are cell surface adhesion molecules that play important roles in development of tissues and organs. In this study we analyzed expression pattern of cadherin10, a member of the type II classic cadherin subfamily, in the embryonic zebrafish using in situ hybridization methods. cadherin10 message (cdh10) is first and transiently expressed by the notochord. In the developing nervous system, cdh10 was first detected in a subset of the cranial ganglia, then in restricted brain regions and neural retina. As development proceeds, cdh10 expression domain and/or expression levels increased in the embryonic nervous system. Our results show that cdh10 expression in the zebrafish developing nervous system is both spatially and temporally regulated.
PMCID: PMC2562320  PMID: 16488669
zebrafish; development; cell adhesion molecules; brain; cranial and lateral line ganglia
14.  Cadherin-4 Plays a Role in the Development of Zebrafish Cranial Ganglia and Lateral line System 
We previously reported that cadherin4 (also called R-cadherin) was expressed by the majority of the developing zebrafish cranial and lateral line ganglia. Cadherin4 function in the formation of these structures in zebrafish was studied using morpholino antisense technology. Differentiation of the cranial and lateral line ganglia, and lateral line nerve and neuromasts of the cadherin4 morphants was analyzed using multiple neural markers. We found that a subset of the morphants cranial and lateral line ganglia were disorganized, smaller, with reduced staining, and/or with altered shape compared to control embryos. Increased cell death in the morphant ganglia likely contributed to these defects. Moreover, cadherin4 morphants had shorter lateral line nerves and reduced number of neuromasts, which was likely caused by disrupted migration of the lateral line primordia. These results indicate that cadherin4 plays a role in the normal formation of the zebrafish lateral line system and a subset of the cranial ganglia.
PMCID: PMC2504752  PMID: 17279575
zebrafish; development; lateral line nerve, neuromasts; cell adhesion molecules; cranial nerves
15.  Cloning and expression analysis of cadherin7 in the central nervous system of the embryonic zebrafish 
Gene expression patterns : GEP  2006;7(1-2):15-22.
Cadherin cell adhesion molecules exhibit unique expression patterns during development of the vertebrate central nervous system. In this study we obtained a full-length cDNA of a novel zebrafish cadherin using reverse transcriptase-polymerase chain reaction (RT-PCR) and 5′ and 3′ rapid amplification of cDNA ends (RACE). The deduced amino acid sequence of this molecule is most similar to the published amino acid sequences of chicken and mammalian cadherin7 (Cdh7), a member of the type II cadherin subfamily. cadherin7 message (cdh7) expression in embryonic zebrafish was studied using in situ hybridization and RT-PCR methods. cdh7 expression begins at about 12 hours post fertilization (hpf) in a small patch in the anterior neural keel, and along the midline of the posterior neural keel. By 24 hpf, cdh7 expression in the brain shows a distinct segmental pattern that reflects the neuromeric organization of the brain, while its expression domain in the spinal cord is continuous, but confined to the middle region of the spinal cord. As development proceeds, cdh7 expression is detected in more regions of the brain, including the major visual structures in the fore- and midbrains, while its expression domain in the hindbrain becomes more restricted, and its expression in the spinal cord becomes undetectable. cdh7 expression becomes reduced in 3-day old embryos. Our results show that cdh7 expression in the zebrafish developing central nervous system is both spatially and temporally regulated.
PMCID: PMC1716651  PMID: 16774849
zebrafish; development; cell adhesion molecules; brain; spinal cord; visual system
16.  cadherin-6 message Expression in the Nervous System of Developing Zebrafish 
Cadherins are cell surface adhesion molecules that play important roles in development of a variety of tissues including the nervous system. In this study we analyzed expression pattern of cadherin-6, a member of the type II cadherin subfamily, in the embryonic zebrafish nervous system using in situ hybridization methods. cadherin-6 message is first expressed by the neural keel, then by restricted regions in the brain and spinal cord. cadherin-6 expression in the brain transiently delineates specific brain regions. In the peripheral nervous system, cadherin-6 message is expressed by the neurogenic placodes and the dorsal root ganglia. As development proceeds, cadherin-6 expression domain and/or expression levels increased in the embryonic nervous system. Our results show that cadherin-6 expression in the zebrafish developing nervous system is both spatially and temporally regulated, implicating a role for cadherin-6 in the formation of these nervous structures.
PMCID: PMC1360229  PMID: 16258934
zebrafish; development; cell adhesion molecules; brain, cranial ganglia, lateral line system
17.  Cadherin2 (N-cadherin) plays an essential role in zebrafish cardiovascular development 
Cadherins are cell surface adhesion molecules that play important roles in development of vertebrate tissues and organs. We studied cadherin2 expression in developing zebrafish heart using in situ hybridization and immunocytochemical methods, and we found that cadherin2 was strongly expressed by the myocardium of the embryonic zebrafish. To gain insight into cadherin2 role in the formation and function of the heart, we analyzed cardiac differentiation and performance in a cadherin2 mutant, glass onion (glo).
We found that the cadherin2 mutant had enlarged pericardial cavity, disorganized atrium and ventricle, and reduced expression of a ventricular specific marker vmhc. Individual myocardiocytes in the glo mutant embryos became round shaped and loosely aggregated. In vivo measurements of cardiac performance revealed that the mutant heart had significantly reduced heart rate, stroke volume and cardiac output compared to control embryos. Formation of the embryonic vascular system in the glo mutants was also affected.
Our results suggest that cadherin2 plays an essential role in zebrafish cardiovascular development. Although the exact mechanisms remain unknown as to the formation of the enlarged pericardium and reduced peripheral blood flow, it is clear that myocardiocyte differentiation and physiological cardiovascular performance is impaired when cadherin2 function is disrupted.
PMCID: PMC1523202  PMID: 16719917
18.  Genes Underlying Positive Influence of Prenatal Environmental Enrichment and Negative Influence of Prenatal Earthquake Simulation and Corrective Influence of Chinese Herbal Medicine on Rat Offspring: Irf7 and Ninj2 
Prenatal environmental enrichment (EE) has been proven to positively affect but prenatal stress negatively influence the physiological and psychological processes in animals, whose trans-generational genetic mechanism remains unclearly defined. We aimed to investigate and find out key genes underlying the positive-negative effects derived from prenatal interventions.
Materials and Methods
Pregnant rats were randomized into EE group (EEG), earthquake simulation group (ESG), herbal group (HG) received herbal supplements in feed after earthquake simulation, and control group (CG).
Light Box Defecation Test (LBDT) showed EEG offspring presented less fecal pellets than CG offspring, ESG's more than CG's, and HG's less than ESG (p's<0.05). Open-field Test (OFT) score of EEG was higher than CG offspring, of ESG's was lower than CG's, and HG's higher than ESG's. Irf7 and Ninj were screened, which were up-regulated in EEG, down-regulated in ESG (FC<0.5), and were neutralized in HG. Prenatal EE could positively promote the nervous system development, prenatal earthquake simulation could retard the nervous system development and Chinese herbal remedy (JKSQW) which could correct the retardation.
The negative-positive prenatal effect could contribute to altered gene expression of Irf7 and Ninj2 which also could play a key role in the improving function of JKSQW for the kidneys.
PMCID: PMC4202648  PMID: 25435624
Prenatal stress; Earthquake simulation; Light Box Defecation Test; Open-field Test; Irf7; Ninj2
19.  Sevoflurane Postconditioning Protects Rat Hearts against Ischemia-Reperfusion Injury via the Activation of PI3K/AKT/mTOR Signaling 
Scientific Reports  2014;4:7317.
Phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway plays a key role in myocardial ischemia-reperfusion (I/R) injury. Mammalian target of rapamycin (mTOR), a downstream target of PI3K/AKT signaling, is necessary and sufficient to protect the heart from I/R injury. Inhaled anesthetic sevoflurane is widely used in cardiac surgeries because its induction and recovery are faster and smoother than other inhaled anesthetics. Sevoflurane proved capable of inducing postconditioning effects in the myocardium. However, the underlying molecular mechanisms for sevoflurane-induced postconditioning (SPC) were largely unclear. In the present study, we demonstrated that SPC protects myocardium from I/R injury with narrowed cardiac infarct focus, increased ATP content, and decreased cardiomyocyte apoptosis, which are mainly due to the activation of PI3K/AKT/mTOR signaling and the protection of mitochondrial energy metabolism. Application of dactolisib (BEZ235), a PI3K/mTOR dual inhibitor, abolishes the up-regulation of pho-AKT, pho-GSK, pho-mTOR, and pho-p70s6k induced by SPC, hence abrogating the anti-apoptotic effect of sevoflurane and reducing SPC-mediated protection of heart from I/R injury. As such, this study proved that PI3K/AKT/mTOR pathway plays an important role in SPC induced cardiac protection against I/R injury.
PMCID: PMC4255182  PMID: 25471136
20.  BCDP: Budget Constrained and Delay-Bounded Placement for Hybrid Roadside Units in Vehicular Ad Hoc Networks 
Sensors (Basel, Switzerland)  2014;14(12):22564-22594.
In vehicular ad hoc networks, roadside units (RSUs) placement has been proposed to improve the the overall network performance in many ITS applications. This paper addresses the budget constrained and delay-bounded placement problem (BCDP) for roadside units in vehicular ad hoc networks. There are two types of RSUs: cable connected RSU (c-RSU) and wireless RSU (w-RSU). c-RSUs are interconnected through wired lines, and they form the backbone of VANETs, while w-RSUs connect to other RSUs through wireless communication and serve as an economical extension of the coverage of c-RSUs. The delay-bounded coverage range and deployment cost of these two cases are totally different. We are given a budget constraint and a delay bound, the problem is how to find the optimal candidate sites with the maximal delay-bounded coverage to place RSUs such that a message from any c-RSU in the region can be disseminated to the more vehicles within the given budget constraint and delay bound. We first prove that the BCDP problem is NP-hard. Then we propose several algorithms to solve the BCDP problem. Simulation results show the heuristic algorithms can significantly improve the coverage range and reduce the total deployment cost, compared with other heuristic methods.
PMCID: PMC4299028  PMID: 25436656
roadside unit; facility placement; delay bound; vehicular sensor networks
21.  Concurrent MEK2 mutation and BRAF amplification confer resistance to BRAF and MEK inhibitors in melanoma 
Cell reports  2013;4(6):1090-1099.
Although BRAF and MEK inhibitors have proven clinical benefits in melanoma, most patients develop resistance. We report a de novo MEK2-Q60P mutation and BRAF gain in a melanoma from a patient who progressed on the MEK inhibitor trametinib and did not respond to the BRAF inhibitor dabrafenib. We also identified the same MEK2-Q60P mutation along with BRAF amplification in a xenograft tumor derived from a second melanoma patient resistant to the combination of dabrafenib and trametinib. Melanoma cells chronically exposed to trametinib acquired concurrent MEK2-Q60P mutation and BRAF-V600E amplification, which conferred resistance to MEK and BRAF inhibitors. The resistant cells had sustained MAPK activation and persistent phosphorylation of S6K. A triple combination of dabrafenib, trametinib, and the PI3K/mTOR inhibitor GSK2126458 led to sustained tumor growth inhibition. Hence, concurrent genetic events that sustain MAPK signaling can underlie resistance to both BRAF and MEK inhibitors, requiring novel therapeutic strategies to overcome it.
PMCID: PMC3956616  PMID: 24055054
22.  The p130 Isoform of Angiomotin Is Required for Yap-Mediated Hepatic Epithelial Cell Proliferation and Tumorigenesis 
Science signaling  2013;6(291):ra77.
The Hippo-Yap signaling pathway regulates a number of developmental and adult cellular processes, including cell fate determination, tissue growth, and tumorigenesis. Members of the scaffold protein angiomotin (Amot) family interact with several Hippo pathway components, including Yap (Yes-associated protein), and either stimulate or inhibit Yap activity. We used a combination of genetic, biochemical, and transcriptional approaches to assess the functional consequences of the Amot-Yap interaction in mice and in human cells. Mice with a liver-specific Amot knockout exhibited reduced hepatic “oval cell” proliferation and tumorigenesis in response to toxin-induced injury or when crossed with mice lacking the tumor suppressor Nf2. Biochemical examination of the Amot-Yap interaction revealed that the p130 splicing isoform of Amot (Amot-p130) and Yap interacted in both the cytoplasm and nucleus, which involved binding of PPxY and LPxY motifs in Amot-p130 to WW domains of Yap. In the cytoplasm, Amot-p130 prevented the phosphorylation of Yap by blocking access of the WW domains to the kinase Lats1. Within the nucleus, Amot-p130 was associated with the transcriptional complex containing Yap and Teads (TEA domain family members) and contributed to the regulation of a subset of Yap target genes, many of which are associated with tumorigenesis. These findings indicated that Amot acts as a Yap cofactor, preventing Yap phosphorylation and augmenting its activity toward a specific set of genes that facilitate tumorigenesis.
PMCID: PMC4175526  PMID: 24003254
23.  Protein isoform-specific validation defines multiple chloride intracellular channel and tropomyosin isoforms as serological biomarkers of ovarian cancer 
Journal of proteomics  2013;89:165-178.
New serological biomarkers for early detection and clinical management of ovarian cancer are urgently needed, and many candidates have been reported. A major challenge frequently encountered when validating candidates in patients is establishing quantitative assays that distinguish between highly homologous proteins. The current study tested whether multiple members of two recently discovered ovarian cancer biomarker protein families, chloride intracellular channel (CLIC) proteins and tropomyosins (TPM), were detectable in ovarian cancer patient sera. A multiplexed, label-free multiple reaction monitoring (MRM) assay was established to target peptides specific to all detected CLIC and TPM family members, and their serum levels were quantitated for ovarian cancer patients and non-cancer controls. In addition to CLIC1 and TPM1, which were the proteins initially discovered in a xenograft mouse model, CLIC4, TPM2, TPM3, and TPM4 were present in ovarian cancer patient sera at significantly elevated levels compared with controls. Some of the additional biomarkers identified in this homolog-centric verification and validation approach may be superior to the previously identified biomarkers at discriminating between ovarian cancer and non-cancer patients. This demonstrates the importance of considering all potential protein homologs and using quantitative assays for cancer biomarker validation with well-defined isoform specificity.
PMCID: PMC3779132  PMID: 23792823
24.  Tobacco Dependence Treatment Teaching by Medical School Clerkship Preceptors: Survey Responses from more than 1,000 US Medical Students 
Preventive medicine  2013;57(2):81-86.
To determine factors associated with tobacco cessation counseling in medical school clerkships
Third-year medical students at 10 medical schools across the United States completed a 100-item survey, measuring the frequency with which they experienced their preceptors’ providing clinical teaching components: clear instruction, feedback, modeling behavior, setting clear objectives, and responding to questions about tobacco dependence counseling as well as frequency of use of tobacco prompts and office systems. Our primary dependent measure was student self-reported skill level for items of tobacco dependence treatment (e.g. “5As”).
Surveys were completed by 1213 students. For both family medicine and internal medicine clerkships, modeling and providing clear instruction on ways to provide tobacco counseling were reported most commonly. In contrast, providing feedback and clear objectives for tobacco dependence treatment lagged behind. Overall, students who reported preceptors’ provision of optimal clinical teaching components and office system prompts in both family medicine and internal medicine clerkships had higher self-reported skill (p<0.001) than students with no exposure or exposure during only one of the clerkships.
Future educational interventions intended to help students adopt effective tobacco dependence treatment techniques should be engineered to facilitate these critical precepting components.
PMCID: PMC3767283  PMID: 23623894
25.  A Correlate of HIV-1 Control Consisting of Both Innate and Adaptive Immune Parameters Best Predicts Viral Load by Multivariable Analysis in HIV-1 Infected Viremic Controllers and Chronically-Infected Non-Controllers 
PLoS ONE  2014;9(7):e103209.
HIV-1 infected viremic controllers maintain durable viral suppression below 2000 copies viral RNA/ml without anti-retroviral therapy (ART), and the immunological factor(s) associated with host control in presence of low but detectable viral replication are of considerable interest. Here, we utilized a multivariable analysis to identify which innate and adaptive immune parameters best correlated with viral control utilizing a cohort of viremic controllers (median 704 viral RNA/ml) and non-controllers (median 21,932 viral RNA/ml) that were matched for similar CD4+ T cell counts in the absence of ART. We observed that HIV-1 Gag-specific CD8+ T cell responses were preferentially targeted over Pol-specific responses in viremic controllers (p = 0.0137), while Pol-specific responses were positively associated with viral load (rho = 0.7753, p = 0.0001, n = 23). Viremic controllers exhibited significantly higher NK and plasmacytoid dendritic cells (pDC) frequency as well as retained expression of the NK CD16 receptor and strong target cell-induced NK cell IFN-gamma production compared to non-controllers (p<0.05). Despite differences in innate and adaptive immune function however, both viremic controllers (p<0.05) and non-controller subjects (p<0.001) exhibited significantly increased CD8+ T cell activation and spontaneous NK cell degranulation compared to uninfected donors. Overall, we identified that a combination of innate (pDC frequency) and adaptive (Pol-specific CD8+ T cell responses) immune parameters best predicted viral load (R2 = 0.5864, p = 0.0021, n = 17) by a multivariable analysis. Together, this data indicates that preferential Gag-specific over Pol-specific CD8+ T cell responses along with a retention of functional innate subsets best predict host control over viral replication in HIV-1 infected viremic controllers compared to chronically-infected non-controllers.
PMCID: PMC4117509  PMID: 25078947

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