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1.  Association between MMP1 -1607 1G>2G Polymorphism and Head and Neck Cancer Risk: A Meta-Analysis 
PLoS ONE  2013;8(2):e56294.
Background
MMP1 is an important member of the MMP endopeptidase family that plays a critical role in the development of head and neck cancer (HNC). Several studies have investigated the association between the MMP1 -1607 1G>2G polymorphism and risk of HNC, but their results have been inconsistent. Here, we conducted a meta-analysis to further explore the role of the MMP1 -1607 1G>2G polymorphism in HNC development.
Methods
We identified all eligible studies in the electronic databases of PubMed, ISI Web of Knowledge, MEDLINE, Embase, and Google Scholar (from January 2000 to June 2012). A meta-analysis was performed to evaluate the association between the MMP1 -1607 1G>2G polymorphism and risk of HNC by calculating odds ratios (OR) and 95% confidence interval (CIs).
Results
Twelve studies were included in this meta-analysis. In overall comparison, significant associations were found using the recessive and allelic contrast models (OR, 1.38; 95% CI, 1.07–1.79 and OR, 1.27; 95% CI, 1.05–1.53, respectively), but no association was detected using the dominant model. In the stratified analyses by several variables, significant associations were observed using the recessive, dominant, and allelic contrast models in the Asian population (OR, 1.64; 95% CI, 1.29–2.08; OR, 1.39; 95% CI, 1.06–1.82; and OR, 1.41; 95% CI, 1.21–1.65, respectively), European population (OR, 0.58; 95% CI, 0.40–0.84; OR, 0.64; 95% CI, 0.44–0.92; and OR, 0.68; 95% CI, 0.54–0.85, respectively), and population-based subgroup (OR, 1.24; 95% CI,1.05–1.47; OR,1.48; 95% CI,1.04–2.12; and OR, 1.22; 95% CI, 1.07–1.38, respectively). Furthermore, significant associations were detected in oral cavity cancer and nasopharyngeal cancer under the recessive model.
Conclusion
Our results suggest that the MMP1 -1607 1G>2G polymorphism is associated with risk of HNC and that it plays different roles in Asian and European populations. Further studies with large sample size are needed to validate our findings.
doi:10.1371/journal.pone.0056294
PMCID: PMC3575339  PMID: 23441173
2.  MicroRNA Variants Increase the Risk of HPV-Associated Squamous Cell Carcinoma of the Oropharynx in Never Smokers 
PLoS ONE  2013;8(2):e56622.
Background
Both microRNAs and human papillomavirus (HPV) infection play an important role in the development and progression of oral squamous cell carcinoma (OSCC). In addition, microRNAs affect all facets of the immune/inflammation responses to infection, which may control HPV clearance. We thus hypothesized that microRNA polymorphisms modify the association between HPV16 seropositivity and OSCC risk.
Methods
Four single-nucleotide polymorphisms in microRNAs were genotyped and HPV16 serology was determined in 325 cases and 335 matched controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using univariate and multivariable logistic regression models.
Results
Overall, each polymorphism had no significant main effect on OSCC risk. Compared with the risk among individuals with both miR146 rs2910164 GG genotype and HPV16 seronegativity, risk of OSCC was increased among those with CG or CC genotype and HPV16 seronegativity (OR, 1.2; 95% CI, 0.9–1.8), GG genotype and HPV16 seropositivity (OR, 3.0; 95% CI, 1.8–5.0), and CG or CC genotype and HPV16 seropositivity (OR, 4.7; 95% CI, 2.3–9.4). Similar results were found for miR149 rs2292832, miR196 rs11614913, and miR499 rs3746444. Analyses stratified by tumor sites and smoking status showed that each polymorphism significantly increased the risk of HPV16-associated squamous cell carcinoma of the oropharynx (SCCOP), and such effect modification was particularly prominent in never smokers.
Conclusions
Our results indicate that microRNA polymorphisms modify the risk of OSCC associated with HPV16 seropositivity, particularly in patients with SCCOP and never smokers. Larger studies are needed to verify our findings.
doi:10.1371/journal.pone.0056622
PMCID: PMC3574010  PMID: 23457596
3.  VISA is Required for B Cell Expression of TLR7 
B cells play a critical role in the initialization and development of the Systemic Lupus Erythematosus (SLE) that is dependent on the expression of the endosomal ssRNA receptor TLR7. Previous studies have established that B cell expression of TLR7 is controlled by the Type I IFN secreted by Plasmacytoid Dendritic Cells (PDC). Here we report that VISA, also known as MAVS, IPS-1 and CardIf, essential for RIG-I/MDA5-mediated signaling following sensing of cytosolic RNA, regulate B cell expression of TLR7 and CD23. We found that B cells from VISA−/− mouse express reduced TLR7, but normal basal levels of Type I IFN. We also show that while IFNβ and TLR7 agonists synergize to promote TLR7 expression in VISA−/− B cells, they do not fully complement the defect seen in VISA−/− cells. Cell transfer experiments revealed that the observed effects of VISA−/− are B cell intrinsic. The reduced TLR7 expression in B cells is correlated with impaired TLR7 agonist-induced up-regulation of activation markers CD69 and CD86, cell proliferation, production of IFNα, TNF, IL-12 and NF-κB activation. Finally, studies indicate that genetic background may influence the observed phenotype of our VISA−/− mice, since VISA−/− B cells differ in CD23 and TLR7 expression when on C57BL/6 vs 129Sv-C57BL/6 background. Thus, our findings suggest an unexpected link between VISA-mediated cytosolic RLR signaling and autoimmunity.
doi:10.4049/jimmunol.1100918
PMCID: PMC3244560  PMID: 22105994
4.  Genome-Wide Expression Analysis in Down Syndrome: Insight into Immunodeficiency 
PLoS ONE  2012;7(11):e49130.
Down syndrome (DS) is caused by triplication of Human chromosome 21 (Hsa21) and associated with an array of deleterious phenotypes, including mental retardation, heart defects and immunodeficiency. Genome-wide expression patterns of uncultured peripheral blood cells are useful to understanding of DS-associated immune dysfunction. We used a Human Exon microarray to characterize gene expression in uncultured peripheral blood cells derived from DS individuals and age-matched controls from two age groups: neonate (N) and child (C). A total of 174 transcript clusters (gene-level) with eight located on Hsa21 in N group and 383 transcript clusters including 56 on Hsa21 in C group were significantly dysregulated in DS individuals. Microarray data were validated by quantitative polymerase chain reaction. Functional analysis revealed that the dysregulated genes in DS were significantly enriched in two and six KEGG pathways in N and C group, respectively. These pathways included leukocyte trans-endothelial migration, B cell receptor signaling pathway and primary immunodeficiency, etc., which causally implicated dysfunctional immunity in DS. Our results provided a comprehensive picture of gene expression patterns in DS at the two developmental stages and pointed towards candidate genes and molecular pathways potentially associated with the immune dysfunction in DS.
doi:10.1371/journal.pone.0049130
PMCID: PMC3498323  PMID: 23155455
5.  Genetic Variation in MDM2 and p14ARF and Susceptibility to Salivary Gland Carcinoma 
PLoS ONE  2012;7(11):e49361.
Background
The p14ARF/MDM2/p53 pathway plays an important role in modulation of DNA damage and oxidative stress responses. The aim of this study was to determine whether genetic variants in MDM2 and p14ARF are associated with risk of salivary gland carcinoma (SGC).
Methods
Four single nucleotide polymorphisms (SNPs) in MDM2 and p14ARF (MDM2-rs2279744, MDM2-rs937283, p14ARF-rs3731217, and p14ARF-rs3088440) were genotyped in 156 patients with SGC and 511 cancer-free controls. Multivariate logistic regression analysis was performed to calculate odds ratios (ORs) and 95% confidence intervals (CIs).
Results
MDM2-rs2279744 was significantly associated with a moderately increased risk of SGC (OR, 1.5, 95% CI, 1.1–2.2). There was a trend toward significantly increased SGC risk with increasing number of risk genotypes of the four polymorphisms (Ptrend = 0.004). Individuals carrying 3–4 risk genotypes in MDM2 and p14ARF were at increased SGC risk (OR, 2.0, 95% CI, 1.1–2.7) compared with individuals carrying 0–2 risk genotypes. Moreover, the combined effect of risk genotypes of MDM2 and p14ARF was more pronounced among young subjects (≤45 years), female subjects, subjects with race/ethnicity other than non-Hispanic white, ever-smokers, and ever-drinkers.
Conclusion
Our results support the involvement of SNPs of MDM2 and p14ARF, either alone or more likely in combination, in susceptibility to SGC. Larger studies are needed to validate our findings.
doi:10.1371/journal.pone.0049361
PMCID: PMC3492289  PMID: 23145162
6.  Natural Killer Cells Are Characterized by the Concomitantly Increased Interferon-γ and Cytotoxicity in Acute Resolved Hepatitis B Patients 
PLoS ONE  2012;7(11):e49135.
Natural killer (NK) cells are abundant in the liver and have been implicated in inducing hepatocellular damage in patients with chronic hepatitis B virus (HBV) infection. However, the role of NK cells in acute HBV infection remains to be elucidated. We comprehensively characterized NK cells and investigated their roles in HBV clearance and liver pathology in 19 chronic hepatitis B (CHB) patients and 21 acute hepatitis B (AHB) patients as well as 16 healthy subjects. It was found that NKp46+ NK cells were enriched in the livers of AHB and CHB patients. We further found that peripheral NK cells from AHB patients expressed higher levels of activation receptors and lower levels of inhibitory receptors than those from CHB patients and HC subjects, thus displaying the increased cytolytic activity and interferon-γ production. NK cell activation levels were also correlated positively with serum alanine aminotransferase levels and negatively with plasma HBV DNA levels in AHB patients, which is further confirmed by the longitudinal follow-up of AHB patients. Serum pro-inflammatory cytokine and chemokine levels were also increased in AHB patients as compared with CHB and HC subjects. Thus, the concomitantly increased interferon-γ and cytotoxicity of NK cells were associated with liver injury and viral clearance in AHB patients.
doi:10.1371/journal.pone.0049135
PMCID: PMC3486810  PMID: 23133672
7.  Single action potentials and subthreshold electrical events imaged in neurons with a novel fluorescent protein voltage probe 
Neuron  2012;75(5):779-785.
Summary
Monitoring neuronal electrical activity using fluorescent protein-based voltage sensors has been limited by small response magnitudes and slow kinetics of existing probes. Here we report the development of a novel fluorescent protein voltage sensor, named ArcLight, and derivative probes that exhibit large changes in fluorescence intensity in response to voltage changes. ArcLight consists of the voltage-sensing domain of Ciona intestinalis voltage-sensitive phosphatase and super ecliptic pHluorin that carries the point mutation A227D. The fluorescence intensity of ArcLight A242 decreases 35% in response to +100mV depolarization when measured in HEK 293 cells, which is more than five times larger than the signals from previously reported fluorescent protein voltage sensors. We show that the combination of signal size and response speed of these new probes, for the first time, allows the reliable detection of single action potentials and excitatory potentials in individual neurons and dendrites.
doi:10.1016/j.neuron.2012.06.040
PMCID: PMC3439164  PMID: 22958819
8.  Prevalence of Toxoplasma gondii antibodies, circulating antigens and DNA in stray cats in Shanghai, China 
Parasites & Vectors  2012;5:190.
Background
Toxoplasma gondii is prevalent in most areas of the world and may cause abortions or neonatal complications in humans. As the only definitive host, cats play an important role in the epidemiology of the disease. Infection rates in cats, especially stray or free-living cats, are considered to be the best sentinels of the level of T. gondii in the environment. The T. gondii infection can be diagnosed in different ways with different methods depending on the target. However, little information on T. gondii infection in cats was available in Shanghai, China. Moreover reports on prevalence of circulating antigens, antibodies and DNA of T. gondii in the same study are rare.
Methods
In the present study, the presence of antibodies (Ab), circulating antigens (CA), and/or DNA of Toxoplasma gondii in samples from 145 stray or unwanted cats from 6 animal shelters in Shanghai (China) was determined in order to estimate the prevalence of T. gondii infection, by Ab-ELISA, CA-ELISA, and nested-PCR, respectively.
Results
The positive rates for the antibodies, circulating antigen and DNA of T. gondii were 11.7% (17 of 145), 5.5% (8 of 145) and 5.71% (2 of 35), respectively. No cat tested was positive by both the Ab-ELISA and the CA-ELISA, but the results of the PCR were consistent with the CA-ELISA assay. Therefore, the overall estimated prevalence of toxoplasmosis was 17.2% (25 of 145). According to our results, the positive rates of specific antibodies and circulating antigen of T. gondii were significantly different between adult cats (>1 year old) and juvenile cats (≤1 year old); the former was 13.5% versus 3.9% by Ab-ELISA, while the latter was 1.7% versus 23.1% by CA-ELISA. From the results obtained with all three detection methods used in this study, the rate of infection was not significantly different between male and female cats (P ≥0.05); and the overall rate was 17.9% for males versus 16.4% for females.
Conclusions
The results suggest that detection of circulating antigens (CA) is necessary in surveys of T. gondii infection, especially for juvenile cats. Our investigation revealed that the prevalence of T. gondii infection in stray cats in Shanghai is high. Control programs are needed for stray cat populations in order to reduce the risk of zoonotic transmission of toxoplasmosis to other domestic animals and humans, especially females.
doi:10.1186/1756-3305-5-190
PMCID: PMC3453520  PMID: 22950630
Prevalence; Toxoplasma gondii; Stray cats; Ab-ELISA; CA-ELISA; PCR; Shanghai; Epidemiology; Environment; Indicator
9.  MPYS is required for IRF3 activation and type I IFN production in the response of cultured phagocytes to bacterial second messengers c-di-AMP and c-di-GMP1 
Cyclic-di-GMP and cyclic-di-AMP are second messengers produced by bacteria and influence bacterial cell survival, differentiation, colonization, biofilm formation, virulence, and bacteria-host interactions. Here, we show that in both RAW264.7 macrophage cells and primary bone-marrow–derived macrophages (BMM) the production of IFNβ and IL-6, but not TNF, in response to cyclic-di-AMP and cyclic-di-GMP requires MPYS (also known as STING, MITA, and TMEM173). Furthermore, expression of MPYS was required for interferon response factor (IRF)-3 but not nuclear factor κB (NFκB) activation in response to these bacterial metabolites. We also confirm that MPYS is required for type I IFN production by cultured macrophages infected with the intracellular pathogens Listeria monocytogenes and Francisella tularensis. However, during systemic infection with either pathogen, MPYS deficiency did not impact bacterial burdens in infected spleens. Serum IFNβ and IL-6 concentrations in the infected control and MPYS−/− mice were also similar at 24 hpi, suggesting that these pathogens stimulate MPYS-independent cytokine production during in vivo infection. Our findings indicate that bifurcating MPYS-dependent and -independent pathways mediate sensing of cytosolic bacterial infections.
doi:10.4049/jimmunol.1100088
PMCID: PMC3159690  PMID: 21813776
10.  3.3 Å Cryo-EM Structure of a Nonenveloped Virus Reveals a Priming Mechanism for Cell Entry 
Cell  2010;141(3):472-482.
SUMMARY
To achieve cell entry, many nonenveloped viruses must transform from a dormant to a primed state. In contrast to the membrane fusion mechanism of enveloped viruses (e.g., influenza virus), this membrane penetration mechanism is poorly understood. Here, using single-particle cryo-electron microscopy, we report a 3.3 Å structure of the primed, infectious subvirion particle of aquareovirus. The density map reveals side-chain densities of all types of amino acids (except glycine), enabling construction of a full-atom model of the viral particle. Our structure and biochemical results show that priming involves autocleavage of the membrane penetration protein and suggest that Lys84 and Glu76 may facilitate this autocleavage in a nucleophilic attack. We observe a myristoyl group, covalently linked to the N terminus of the penetration protein and embedded in a hydrophobic pocket. These results suggest a well-orchestrated process of nonenveloped virus entry involving autocleavage of the penetration protein prior to exposure of its membrane-insertion finger.
doi:10.1016/j.cell.2010.03.041
PMCID: PMC3422562  PMID: 20398923
11.  Atomic structure of human adenovirus by cryoEM reveals interactions among protein networks 
Science (New York, N.Y.)  2010;329(5995):1038-1043.
Construction of a complex virus may involve a hierarchy of assembly elements. Here, we report the structure of the whole human adenovirus virion at 3.6Å resolution by cryo-electron microscopy, revealing in situ atomic models of three minor capsid proteins (IIIa, VIII and IX), extensions of the major (penton base and hexon) capsid proteins, and interactions within three protein-protein networks. One network is mediated by protein IIIa within Group-of-Six (GOS) tiles – a penton base and its five surrounding hexons – at vertices. Another is mediated by ropes (protein IX) that lash hexons together to form Group-of-Nine (GON) tiles and bind GONs to GONs. The third, mediated by IIIa and VIII, binds each GOS to five surrounding GONs. Optimization of adenovirus for cancer and gene therapy could target these networks.
doi:10.1126/science.1187433
PMCID: PMC3412078  PMID: 20798312
12.  Random Insertion of Split-cans of the Fluorescent Protein Venus into Shaker Channels Yields Voltage Sensitive Probes with Improved Membrane Localization in Mammalian Cells 
FlaSh-YFP, a fluorescent protein (FP) voltage sensor that is a fusion of the Shaker potassium channel with yellow fluorescent protein (YFP), is primarily expressed in the endoplasmic reticulum (ER) of mammalian cells, possibly due to misfolded monomers. In an effort to improve plasma membrane expression, the FP was split into two non-fluorescent halves. Each half was randomly inserted into Shaker monomers via a transposon reaction. Shaker subunits containing the 5' half were co-expressed with Shaker subunits containing the 3' half. Tetramerization of Shaker subunits is required for re-conjugation of the FP. The misfolded monomers trapped in ER are unlikely to tetramerize and reconstitute the beta-can structure, and thus intracellular fluorescence might be reduced. This split-can transposon approach yielded 56 fluorescent probes, 30 (54%) of which were expressed at the plasma membrane and were capable of optically reporting changes in membrane potential. The largest signal from these novel FP-sensors was a −1.4% in ΔF/F for a 100 mV depolarization, with on time constants of about 15 ms and off time constants of about 200 ms. This split-can transposon approach has the potential to improve other multimeric probes.
doi:10.1016/j.jneumeth.2011.03.028
PMCID: PMC3281265  PMID: 21497167
Split-can; transposon; Venus; Shaker; membrane localization; FP voltage sensor; genetically encoded voltage sensor
13.  Benzyl­triethyl­ammonium tetra­chlorido­ferrate(III) 
In the title mol­ecular salt, (C13H22N)[FeCl4], three of the chloride ions of the tetra­hedral FeIII-containing anion are disordered over two orientations in a 0.656 (11):0.344 (11) ratio. In the crystal, there are no identifiable directional inter­actions between cations and anions except for Coulombic forces.
doi:10.1107/S1600536812023008
PMCID: PMC3379130  PMID: 22719351
14.  Dimeth­yl(3-oxo-3-phenyl­prop­yl)aza­nium tetra­chloridoferrate(III) 
In the title mol­ecular salt, (C11H16NO)[FeCl4], an intra­molecular N—H⋯O hydrogen bond in the cation generates an S(6) loop and the conformation of the C(=O)—C—C—N chain is gauche [torsion angle = 57.0 (6)°]. The anion is a near-regular tetra­hedron [range of Cl—Fe—Cl angles = 107.93 (8)–112.13 (10)°]. There are no directional inter-ionic bonds in the crystal.
doi:10.1107/S1600536812018600
PMCID: PMC3344424  PMID: 22590186
15.  Butyl­triethyl­ammonium tetra­chlorido­ferrate(III) 
In the title compound, (C10H24N)[FeCl4], no classical hydrogen bonds are observed. The butyl­triethyl­ammonium cations inter­act with the tetra­hedral [FeCl4]− anion through weak C—H⋯Cl inter­actions, forming a three-dimensional network.
doi:10.1107/S1600536812017047
PMCID: PMC3344376  PMID: 22590142
16.  Bis(butyl­triethyl­ammonium) di-μ-bromido-bis­[dibromido­mercurate(II)] 
In the title mol­ecular salt, (C10H24N)2[Hg2Br6], the complete anion is generated by crystallographic inversion symmetry, forming a pair of edge-sharing HgBr4 tetra­hedra. In the crystal, the cations and anions are linked by weak C—H⋯Br inter­actions.
doi:10.1107/S1600536812017011
PMCID: PMC3344377  PMID: 22590143
17.  Concentration- and time-dependent response of human gingival fibroblasts to fibroblast growth factor 2 immobilized on titanium dental implants 
Background
Titanium (Ti) implants are widely used clinically, but peri-implantitis remains one of the most common and serious complications. Healthy integration between gingival tissue and the implant surface is critical to long-term success in dental implant therapy. The objective of this study was to investigate how different concentrations of immobilized fibroblast growth factor 2 (FGF2) on the titania nanotubular surface influence the response of human gingival fibroblasts (HGFs).
Methods
Pure Ti metal was anodized at 20 V to form a vertically organized titanium dioxide nanotube array on which three concentrations of FGF2 (250 ng/mL, 500 ng/mL, or 1000 ng/mL) were immobilized by repeated lyophilization. Surface topography was observed and FGF2 elution was detected using enzyme-linked immunosorbent assay. The bioactivity changes of dissolvable immobilized FGF2 were measured by methyl-thiazolyl-tetrazolium assay. Behavior of HGFs was evaluated using adhesion and methyl-thiazolyl-tetrazolium bromide assays.
Results
The FGF2 remained for several days on the modified surface on which HGFs were cultured. Over 90% of the dissolvable immobilized FGF2 had been eluted by Day 9, whereas the FGF2 activity was found to diminish gradually from Day 1 to Day 9. The titania nanotubular surface with an optimal preparing concentration (500 ng/mL) of FGF2 immobilization exhibited improved HGF functions such as cellular attachment, proliferation, and extracellular matrix-related gene expression. Moreover, significant bidirectional as well as concentration- and time-dependent bioactivity was observed.
Conclusion
Synergism of the FGF2-impregnated titanium dioxide nanotubular surface revealed good gingival-implant integration, indicating that these materials might have promising applications in dentistry and other biomedical devices.
doi:10.2147/IJN.S29538
PMCID: PMC3356224  PMID: 22619534
dental implants; titanium dioxide nanotube; fibroblast growth factor 2; extracellular matrix; real-time polymerase chain reaction
18.  Bis(benzyl­trimethyl­ammonium) di-μ-bromido-bis­[dibromido­mercurate(II)] 
In the crystal structure of the title compound, (C10H16N)2[Hg2Br6], the condensed anion consists of two edge-sharing HgBr4 tetrahedra and is situated on a centre of symmetry. The anions are linked to the cations through weak C—H⋯Br inter­actions.
doi:10.1107/S1600536811055887
PMCID: PMC3274863  PMID: 22346810
19.  Identification and Characterization of a Loss-of-Function Human MPYS Variant 
Genes and immunity  2011;12(4):263-269.
MPYS, also known as STING and MITA, is an IFNβ stimulator essential for host defense against RNA, DNA viruses and intracellular bacteria. MPYS also facilitates the adjuvant activity of DNA vaccines. Here we report identification of a distinct human MPYS haplotype that contains three non-synonymous SNPs, R71H-G230A-R293Q (thus named the HAQ haplotype). We estimate, in two cohorts (1074 individuals), that ~3% of Americans are homozygous for this HAQ haplotype. HAQ MPYS exhibits a >90% loss in the ability to stimulate IFNβ production. Furthermore, fibroblasts and macrophage cells expressing HAQ are defective in Listeria monocytogenes infection-induced IFNβ production. Lastly, we find that the loss of IFNβ activity is due primarily to the R71H and R293Q SNPs in HAQ. We hypothesize that individuals carrying HAQ may exhibit heightened susceptibility to viral infection and respond poorly to DNA vaccines.
doi:10.1038/gene.2010.75
PMCID: PMC3107388  PMID: 21248775
SNP; IFNβ; anti-viral signaling; MPYS/STING/MITA
20.  Benzyl­triethyl­ammonium aqua­trichlorido­zincate 
In the crystal structure of the title mol­ecular salt, (C13H22N)[ZnCl3(H2O)], the distorted tetrahedral anions are linked by O—H⋯Cl hydrogen bonds, generating [100] chains. Weak cation-to-anion C—H⋯Cl inter­actions generate a three-dimensional network.
doi:10.1107/S1600536811048823
PMCID: PMC3238703  PMID: 22199580
21.  Bis(benzyl­trimethyl­ammonium) dichromate(VI) 
The asymmetric part of the title compound, (C10H16N)2[Cr2O7], contains one cation and a half of the dichromate dianion, which has a staggered conformation and exhibits disorder of the bridging O atom around the inversion center over two positions in a 1:1 ratio. Weak inter­molecular C—H⋯O hydrogen bonds link cations and anions into a three-dimensional structure.
doi:10.1107/S1600536811043091
PMCID: PMC3246999  PMID: 22219819
22.  Bis(benzyl­trimethyl­ammonium) tetra­bromidocuprate(II) 
In the title mol­ecular salt, (C10H16N)2[CuBr4], the CuII ion adopts a squashed tetra­hedral geometry with Br—Cu—Br angles varying between 99.29 (3) and 132.53 (3)°. In the crystal, the components are linked by C—H⋯Br inter­actions, thereby generating a three-dimensional network.
doi:10.1107/S1600536811034830
PMCID: PMC3200753  PMID: 22058898
23.  Preliminary Evidence Regarding the Hypothesis That the Sex Ratio at Sexual Maturity May Affect Longevity in Men 
Demography  2010;47(3):579-586.
In human populations, variation in mate availability has been linked to various biological and social outcomes, but the possible effect of mate availability on health or survival has not been studied. Unbalanced sex ratios are a concern in many parts of the world, and their implications for the health and survival of the constituent individuals warrant careful investigation. We indexed mate availability with contextual sex ratios and investigated the hypothesis that the sex ratio at sexual maturity might be associated with long-term survival for men. Using two unique data sets of 7,683,462 and 4,183 men who were followed for more than 50 years, we found that men who reached their sexual maturity in an environment with higher sex ratios (i.e., higher proportions of reproductively ready men) appeared to suffer higher long-term mortality risks than those in an environment with lower sex ratios. Mate availability at sexual maturity may be linked via several biological and social mechanisms to long-term survival in men.
PMCID: PMC3000064  PMID: 20879678
24.  Fab crystallization and preliminary X-ray analysis of NC-1, an anti-HIV-1 antibody that recognizes the six-helix bundle core of gp41 
The Fab fragment of NC-1, a murine antibody that specifically recognizes the six-helix bundle core of HIV-1 gp41, has been crystallized in space group P3221. An X-ray diffraction data set was collected at 3.2 Å resolution and a clear molecular-replacement solution was obtained for solution of the structure.
NC-1 is a murine monoclonal antibody that specifically recognizes the six-helix bundle core of the human immunodeficiency virus type 1 (HIV-1) gp41. As such, it is a useful tool for probing gp41 conformations in HIV-1 membrane fusion. To establish the structural basis underlying the NC-1 specificity, X-ray crystallo­graphy was employed to solve its three-dimensional structure. To accomplish this, hybridoma-produced NC-1 antibody was first purified and digested with papain. Its Fab fragment was then purified using size-exclusion chromatography following Fc depletion using a Protein A affinity column. Finally, crystallization of NC-1 Fab was performed by the hanging-drop vapour-diffusion method and the protein was crystallized at pH 8.0 using PEG 6000 as precipitant. The results showed that the NC-1 Fab crystals belonged to the trigonal space group P3221, with unit-cell parameters a = b = 118.7, c = 106.0 Å. There is one Fab molecule in the asymmetric unit, with 67.5% solvent content. An X-ray diffraction data set was collected at 3.2 Å resolution and a clear molecular-replacement solution was obtained for solution of the structure.
doi:10.1107/S1744309110019287
PMCID: PMC2898479  PMID: 20606291
NC-1 antibody; HIV-1 gp41; Fab fragments
25.  Development and application of ‘phosphoflow’ as a tool for immunomonitoring 
Expert review of vaccines  2010;9(6):631-643.
Flow cytometry has revolutionized our ability to monitor immune responses by allowing us to simultaneously track a variety of cell surface and intracellular markers in discrete cell subsets in a highly sensitive and reproducible manner. This is especially critical in this new era of vaccinology trying to tackle the growing problems of chronic viral infections and cancer that not only evade host immune responses, but can negatively manipulate vaccine-induced immune responses. Thus, understanding how lymphocyte signaling is altered under normal and pathological conditions has become more critical. Over the last decade, a new flow cytometry technology called ‘phosphoflow’ (also sometimes called ‘phosflow’), is rapidly developing for tracking multiple intracellular signaling molecules in the immune system at a single-cell level. Antibodies and reagents for tracking both tyrosine-phosphorylated and serine/threonine-phosphorylated signaling intermediaries in key immune signaling pathways have been developed, and phosphoflow is now starting to be applied to a wide variety of both preclinical and clinical studies on lymphocyte responses, as well as the functioning of cancer cells and virally infected cells. Here, we review the development of phosphoflow technology, its modern applications in the field of immunomonitoring and its current limitations. We then provide a perspective on the future of phosphoflow and a vision of how it can be applied to emerging critical questions in human vaccinology and public health.
doi:10.1586/erv.10.59
PMCID: PMC2933839  PMID: 20518718
flow cytometry; immunomonitoring; lymphocyte; phosflow; phosphoflow; phosphorylation; signaling

Results 1-25 (45)