Background

Typhoid and paratyphoid fever are endemic in Hongta District and their prevalence, at 113 per 100,000 individuals, remains the highest in China. However, the exact sources of the disease and its main epidemiological characteristics have not yet been clearly identified.

Methods and Findings

Numbers of typhoid and paratyphoid cases per day during the period 2006 to 2010 were obtained from the Chinese Center of Disease Control (CDC). A number of suspected disease determinants (or their proxies), were considered for use in spatiotemporal analysis: these included locations of discharge canals and food markets, as well as socio-economic and environmental factors. Results showed that disease prevalence was spatially clustered with clusters decreasing with increasing distance from markets and discharge canals. More than half of the spatial variance could be explained by a combination of economic conditions and availability of health facilities. Temporal prevalence fluctuations were positively associated with the monthly precipitation series. Polluted hospital and residential wastewater was being discharged into rainwater canals. Salmonella bacteria were found in canal water, on farmland and on vegetables sold in markets.

Conclusion

Disease transmission in Hongta district is driven principally by two spatiotemporally coupled cycles: one involving seasonal variations and the other the distribution of polluted farmland (where vegetables are grown and sold in markets). Disease transmission was exacerbated by the fact that rainwater canals were being used for disposal of polluted waste from hospitals and residential areas. Social factors and their interactions also played a significant role in disease transmission.

Author Summary

Typhoid and paratyphoid epidemics are serious events in low-income countries; these diseases are notorious for their high infection rate, long duration, and heavy health burden. In China, typhoid and paratyphoid are considered to be under control, although the situation varies considerably from place to place. During 2010 the disease incidence was 1.2 per 100,000 at the national level. The highest incidence, 113 per 100,000, occurred in the Hongta District of Yunnan province, in southwestern China. We used quantitative spatiotemporal analysis to explore the relationship between the incidence of these diseases and a number of factors suspected of influencing their occurrence. We found that cases tended to occur near discharge canals and polluted farmland where vegetables are grown for sale in local markets. The spatial characteristics of disease transmission were associated with the seasonal variations common to all intestinal infectious diseases. The findings of this work could inform local public health planners and the health directorate and help to improve public health intervention programs in regions with the highest incidence of these diseases.

A phytochemical investigation of Monanthotaxis congoensis afforded eight new polyoxygenated cyclohexenes as well as the known compound crotepoxide. The structures were determined using NMR, MS, and optical rotation. One of the new compounds (7) displayed moderate antiproliferative activity against NCI-H460 and M14 cancer cells.

There has been discrepancies between the daily air quality reports of the Beijing municipal government, observations recorded at the U.S. Embassy in Beijing, and Beijing residents’ perceptions of air quality. This study estimates Beijing’s daily area PM2.5 mass concentration by means of a novel technique SPA (Single Point Areal Estimation) that uses data from the single PM2.5 observation station of the U.S Embassy and the 18 PM10 observation stations of the Beijing Municipal Environmental Protection Bureau. The proposed technique accounts for empirical relationships between different types of observations, and generates best linear unbiased pollution estimates (in a statistical sense). The technique extends the daily PM2.5 mass concentrations obtained at a single station (U.S. Embassy) to a citywide scale using physical relations between pollutant concentrations at the embassy PM2.5 monitoring station and at the 18 official PM10 stations that are evenly distributed across the city. Insight about the technique’s spatial estimation accuracy (uncertainty) is gained by means of theoretical considerations and numerical validations involving real data. The technique was used to study citywide PM2.5 pollution during the 423-day period of interest (May 10, 2010 to December 6, 2011). Finally, a freely downloadable software library is provided that performs all relevant calculations of pollution estimation.

Aims

The mammalian soluble epoxide hydrolase (sEH) has both an epoxide hydrolase and a phosphatase domain. The role of sEH hydrolase activity in the metabolism of epoxyeicosatrienoic acids (EETs) and the activation of endothelial nitric oxide synthase (eNOS) in endothelial cells (ECs) has been well defined. However, far less is known about the role of sEH phosphatase activity in eNOS activation. In the present study, we investigated whether the phosphatase domain of sEH was involved in the eNOS activation in ECs.

Methods and results

The level of eNOS phosphorylation in aortas is higher in the sEH knockout (sEH−/−) mice than in wild-type mice. In ECs, pharmacological inhibition of sEH phosphatase or overexpressing sEH with an inactive phosphatase domain enhanced vascular endothelial growth factor (VEGF)-induced NO production and eNOS phosphorylation. In contrast, overexpressing the phosphatase domain of sEH prevented the VEGF-mediated NO production and eNOS phosphorylation at Ser617, Ser635, and Ser1179. Additionally, treatment with VEGF induced a c-Src kinase-dependent increase in transient tyrosine phosphorylation of sEH and the formation of a sEH–eNOS complex, which was abolished by treatment with a c-Src kinase inhibitor, PP1, or the c-Src dominant-negative mutant K298M. We also demonstrated that the phosphatase domain of sEH played a key role in VEGF-induced angiogenesis by detecting the tube formation in ECs and neovascularization in Matrigel plugs in mice.

Conclusion

In addition to epoxide hydrolase activity, phosphatase activity of sEH plays a pivotal role in the regulation of eNOS activity and NO-mediated EC functions.

AIM: To investigate the effectiveness of 5-flurouracil-based neoadjuvant chemotherapy (NAC) for gastroesophageal and gastric cancer by meta-analysis.

METHODS: MEDLINE and manual searches were performed to identify all published randomized controlled trials (RCTs) investigating the efficacy of the flurouracil-based NAC for gastroesophageal and gastric cancer, and RCTs of NAC for advanced gastroesophageal and gastric cancer vs no therapy before surgery. Studies that included patients with metastases at enrollment were excluded. Primary endpoint was the odds ratio (OR) for improving overall survival rate of patients with gastroesophageal and gastric cancer. Secondary endpoints were the OR of efficiency for down-staging tumor and increasing R0 resection in patients with gastroesophageal and gastric cancer. Safety analyses were also performed. The OR was the principal measurement of effect, which was calculated as the treatment group (NAC plus surgery) vs control group (surgery alone) and was presented as a point estimate with 95% confidence intervals (CI). All calculations and statistical tests were performed using RevMan 5.1 software.

RESULTS: Seven RCTs were included for the analysis. A total of 1249 patients with advanced gastroesophageal and gastric cancer enrolled in the seven trials were divided into treatment group (n = 620) and control group (n = 629). The quality scores of the RCTs were assessed according to the method of Jadad. The RCT quality scores ranged from 2 to 7 (5-point scale), with a mean of 3.75. The median follow-up time in these studies was over 3 years. The meta-analysis showed that NAC improved the overall survival rate (OR 1.40, 95%CI 1.11-1.76; P = 0.005), which was statistically significant. The 3-year progression-free survival rate was significantly higher in treatment group than in control group (37.7% vs 27.3%) (OR 1.62, 95%CI 1.21-2.15; P = 0.001). The tumor down-stage rate was higher in treatment group than in control group (55.76% vs 41.38%) (OR 1.77, 95%CI 1.27-2.49; P = 0.0009) and the R0 resection rate of the gastroesophageal and gastric cancer was higher in treatment group than in control group (75.11% vs 68.56%) (OR 1.38, 95%CI 1.03-1.85; P = 0.03), with significant differences. No obvious safety concerns about mortality and complications were raised in these trials. There were no statistically significant differences in perioperative mortality (5.08% vs 4.86%) (OR 1.05, 95%CI 0.57-1.94; P = 0.87 fixed-effect model) and in the complication rate between the two groups (13.25% vs 9.66%) (OR 1.40, 95%CI 0.91-2.14; P = 0.12 fixed-effect model). Trials showed that patients from Western countries favored NAC compared with those from Asian countries (OR 1.40, 95%CI 1.07-1.83). Monotherapy was inferior to multiple chemotherapy (OR 1.40, 95%CI 1.07-1.83). Intravenous administration of NAC was more advantageous than oral route (OR 1.41, 95%CI 1.09-1.81).

CONCLUSION: Flurouracil-based NAC can safely improve overall survival rate of patients with gastroesophageal/gastric cancer. Additionally, NAC can down the tumor stage and improve R0 resection.

Background

Hypersensitivity diseases are associated with many severe human illnesses, including leprosy and tuberculosis. Emerging evidence suggests that the pathogenesis and pathological mechanisms of treating these diseases may be attributable to sphingolipid metabolism.

Methods

High performance liquid chromatography-tandem mass spectrometry was employed to target and measure 43 core sphingolipids in the plasma, kidneys, livers and spleens of BALB/c mice from four experimental groups: control, delayed-type hypersensitivity (DTH) model, DTH+triptolide, and control+triptolide. Orthogonal partial least squares discriminant analysis (OPLS-DA) was used to identify potential biomarkers associated with variance between groups. Relationships between the identified biomarkers and disease markers were evaluated by Spearman correlation.

Results

As a treatment to hypersensitivity disease, triptolide significantly inhibit the ear swelling and recover the reduction of splenic index caused by DTH. The sphingolipidomic result revealed marked alterations in sphingolipid levels between groups that were associated with the effects of the disease and triptolide treatment. Based on this data, 23 potential biomarkers were identified by OPLS-DA, and seven of these biomarkers correlated markedly with the disease markers (p<0.05) by Spearman correlation.

Conclusions

These data indicate that differences in sphingolipid levels in plasma and tissues are related to DTH and treatment with triptolide. Restoration of proper sphingolipid levels may attribute to the therapeutic effect of triptolide treatment. Furthermore, these findings demonstrate that targeted sphingolipidomic analysis followed by multivariate analysis presents a novel strategy for the identification of biomarkers in biological samples.

An amino acid, 3S-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid, was isolated for the first time from the leaves of Cichorium endivia. The complete assignment of its 1H and 13C NMR spectroscopic data was carried out also for the first time based on extensive 1D and 2D NMR experiments. Cytotoxicity of this isolated compound against HCT-8 and HepG2 human cancer cell lines was evaluated for the first time, with moderate activities being found.

The antibacterial activity of royalisin, an antimicrobial peptide from the royal jelly produced by honeybees, has been addressed extensively. However, its mechanism of action remains unclear. In this study, a recombinant royalisin, RAcc-royalisin from the royal jelly of Asian honeybee Apis cerana cerana, was expressed by fusing with glutathione S-transferase (GST) in Escherichia coli BL21, isolated and purified. The agar dilution assays with inhibition zone showed that RAcc-royalisin, similar to nisin, inhibits the growth of Gram-positive bacteria. The antibacterial activity of RAcc-royalisin was associated with its concentration, and was weakened by heat treatment ranging from 55°C to 85°C for 15 min. Both RAcc-royalisin and nisin exhibited the minimum inhibitory concentrations (MIC) of 62.5 µg/ml, 125 µg/ml, and 250 µg/ml against Gram-positive bacterial strains, Bacillus subtilis and Micrococcus flavus and Staphyloccocus aureus in the microplate assay, respectively. However, RAcc-royalisin did not show antimicrobial activity against tested Gram-negative bacterial and fungal strains. The antibacterial activity of RAcc-royalisin agrees well with the decrease in bacterial cell hydrophobicity, the leakage of 260-nm absorbing materials, and the observation by transmission electron microscopy, all indicating that RAcc-royalisin induced the disruption and dysfunction of cell walls and membranes. This is the first report detailing the antibacterial mechanism of royalisin against Gram-positive bacteria, and provides insight into the application of recombinant royalisin in food and pharmaceutical industries as an antimicrobial agent.

In this paper, we first observed that there were differences in expressions of 11β-HSD1 and PPAR-γ, in hippocampi and hypothalami, among constant hyperglycemia group, control group and the fluctuant glycemia group, using Immunohistochemical analysis. However, whether in expression o f 11β-HSD1 or PPAR-γ, there were no statistic differences between the control group or the fluctuant glycemia group. So, we removed the fluctuant glycemia group, retaining only constant hyperglycemia group and control group, being fed for 8 weeks. After 8 weeks of induction, 11β-HSD1 expression increased and PPAR-γ expression decreased in the constant hyperglycemia group compared with control group, both in hippocampi and hypothalami, by Western Blot. The constant hyperglycemia group also showed impaired cognition in MORRIS watermaze, lower serum corticosterone level, and higher Serum ACTH concentration after 8 weeks. We inferred that the cognition impairment may be related to the abnormal expression of 11β-HSD1 and PPAR-γ in central nerves system. As for 11β-HSD1 is a regulating enzyme, converting the inactive 11-dehydrocorticosterone into the active glucocorticoid corticosterone, thus amplifying GC action in local tissues. It is also well known that high local GC levels can affect the cognitive function. In addition, PPAR-a protective receptor, which is related to cognition.

A high-throughput phytochemical investigation of Abronia villosa afforded a new rotenoid designated abronione (1) along with the known compounds boeravinone C and lupeol. The structure of 1 was determined using NMR, MS, and optical analysis with < 400 µg of material. Compound 1 displayed moderate cytotoxicity against NCI-H460 and HL-60 human cancer cell lines with IC50 values of 14 and 36 µM, respectively.

In the last two decades, the accumulation of heavy metal in crop grains has become the study hotspot. In this study, 19 representative elite maize inbred lines and 3 hybrid varieties were investigated at the seedling stage, which can accumulate Pb and Cd in the stems and leaves, respectively. The results demonstrated that significant differences are among inbred lines for accumulation of heavy metals, implying that the Cd accumulation is significant correlation between the male parents and their hybrids and some inbred lines have been selected for cross-breeding with low Pb or Cd accumulation, such as S37, 9782, and ES40; Moreover, some inbred lines could be suitable for phytoremediation species for soil bioremediation with high levels of Pb and Cd accumulation, including 178, R08, 48-2, and Mo17ht.

In the title compound, C10H7BrN2, the non-H atoms, except the N atom of the acetonitrile group and the C atom bonded to it, lie in the least-squares plane defined by the atoms of the indole ring system (r.m.s deviation = 0.019 Å), with the N and C atom of the cyano group displaced by 2.278 (1) and 1.289 (1) Å, respectively, out of that plane. In the crystal, N—H⋯N hydrogen bonds link the mol­ecules into a C(7) chain along [100].

Most known basic-region helix-loop-helix (bHLH) proteins belong to a superfamily of transcription factors often involved in the control of growth and differentiation. Therefore, inappropriate expression of genes encoding bHLH proteins is frequently associated with developmental dysfunction. In our previously reported study, a novel bHLH protein-encoding gene (AO090011000215) of Aspergillus oryzae was identified. The gene-disrupted strain was found to produce dense conidia, but sparse sclerotia, relative to the parent strain. Here, to further analyze its function, we generated an overexpressing strain using the A. oryzae amyB gene promoter. Genetic overexpression led to a large number of initial hyphal aggregations and then the formation of mature sclerotia; it was therefore designated sclR (sclerotium regulator). At the same time, the sclR-overexpressing strain also displayed both delayed and decreased conidiation. Scanning electron microscopy indicated that the aerial hyphae of the sclR-overexpressing strain were extremely branched and intertwined with each other. In the generation of the SclR-enhanced green fluorescent protein (EGFP) expression strain, the SclR-EGFP protein fusion was conditionally detected in the nuclei. In addition, the loss of sclR function led to rapid protein degradation and cell lysis in dextrin-polypeptone-yeast extract liquid medium. Taken together, these observations indicate that SclR plays an important role in hyphal morphology, asexual conidiospore formation, and the promotion of sclerotial production, even retaining normal cell function, at least in submerged liquid culture.

The current study was performed to investigate mitochondrial protection and anti-aging activity of Astragalus polysaccharides (APS) and the potential underlying mechanism. Lipid peroxidation of liver and brain mitochondria was induced by Fe2+–Vit C in vitro. Thiobarbituric acid (TBA) colorimetry was used to measure the content of thiobarbituric acid reactive substances (TBARS). Mouse liver mitochondrial permeability transition (PT) was induced by calcium overload in vitro and spectrophotometry was used to measure it. The scavenging activities of APS on superoxide anion (O2•−) and hydroxyl radical (•OH), which were produced by reduced nicotinamide adenine dinucleotide (NADH)—N-Methylphenazonium methyl sulfate (PMS) and hydrogen peroxide (H2O2)–Fe2+ system respectively, were measured by 4-nitrobluetetrazolium chloride (NBT) reduction and Fenton reaction colorimetry respectively. The Na2S2O3 titration method was used to measure the scavenging activities of APS on H2O2. APS could inhibit TBARS production, protect mitochondria from PT, and scavenge O2•−, •OH and H2O2 significantly in a concentration-dependent manner respectively. The back of the neck of mice was injected subcutaneously with D-galactose to induce aging at a dose of 100 mg/kg/d for seven weeks. Moreover, the activities of catalase (CAT), surperoxide dismutase (SOD) and glutathione peroxidase (GPx) and anti-hydroxyl radical which were assayed by using commercial monitoring kits were increased significantly in vivo by APS. According to this research, APS protects mitochondria by scavenging reactive oxygen species (ROS), inhibiting mitochondrial PT and increasing the activities of antioxidases. Therefore, APS has the effect of promoting health.

The potential energy curves (PECs) of X2∑+, A2Πr and B2∑+ states of BeF radical have been investigated using the complete active space self-consistent-field (CASSCF) method, followed by the highly accurate valence internally contracted multireference configuration interaction (MRCI) approach at the correlation-consistent basis sets, cc-pV5Z for Be and aug-cc-pV6Z for F. Based on the PECs of X2∑+, A2Πr and B2∑+ states, the spectroscopic parameters (De, Re, ωe, ωeχe, αe and Be) have also been determined in the present work. With the PECs determined at the present level of theory, vibrational states have been predicted for each state when the rotational quantum number J equals zero (J = 0). The vibrational levels, inertial rotation and centrifugal distortion constants are determined for the three states, and the classical turning points are also calculated for the X2∑+ state. Compared with the available experiments and other theories, it can be seen that the present spectroscopic parameter and molecular constant results are more fully in agreement with the experimental findings.

In the title compound, C10H7ClN2, the carbonitrile group is twisted away from the plane of the indole ring system [Ccy—Cme—Car—Car = −44.7 (8)°; cy = cyanide, me = methyl­ene and ar = aromatic]. In the crystal, N—H⋯N hydrogen bonds link the mol­ecules into C(7) chains propagating in [010]. Aromatic π–π stacking inter­actions [minimum centroid–centroid separation = 3.663 (3) Å] are also observed.

Background

The Th17 subset and IL-17 have been found in increased frequencies within certain tumors. However, their relevance in cancer biology remains controversial. This study aimed to clarify the biological action of IL-17 on hepatocellular carcinoma (HCC).

Methods

Effects and underlying molecular mechanisms of IL-17 on human HCC were explored in vitro using exogenous IL-17 stimulation and in nude mice by implanting IL-17 overexpressed HCC cells. The clinical significance of IL-17 was investigated in tissue microarrays containing HCC tissues from 323 patients following hepatectomy using immunohistochemistry.

Results

Although exogenous IL-17 showed no direct effect on the growth rate of HCC cells in vitro, PCR and ELISA showed that IL-17 selectively augmented the secretion of diverse proinvasive factors and transwell showed a direct promotion of invasion of HCC cells by IL-17. Furthermore, transfection of IL-17 into HCC cells significantly promoted neoangiogenesis, neutrophil recruitment and tumor growth in vivo. Using siRNA mediated knockdown of AKT and STAT3, we suggested that the effects of IL-17 were operated through activation of the AKT signaling in HCC, which resulted in IL-6 production. Then, IL-6 in turn activated JAK2/STAT3 signaling and subsequently up-regulated its downstream targets IL-8, MMP2, and VEGF. Supporting these findings, in human HCC tissues, immunostaining indicated that IL-17 expression was significantly and positively associated with STAT3 phosphorylation, neutrophil infiltration and increased tumor vascularity. The clinical significance of IL-17 was authenticated by revealing that the combination of intratumoral IL-17+ cells and phospho-STAT3 served as a better prognosticator for postoperative tumor recurrence than either marker alone.

Conclusions

IL-17 mediated tumor-promoting role involves a direct effect on HCC cells through IL-6/JAK2/STAT3 induction by activating the AKT pathway.

In the title compound, C11H10N2O, the O atom and the C atom of the methyl­ene group deviate only slightly [0.029 (3) and 0.055 (3) Å, respectively] from the approximately planar ring system (r.m.s. deviation = 0.013 Å). In the crystal, N—H⋯O hydrogen bonds link the mol­ecules into zigzag chains running along the b axis.

Background

Escherichia coli O157:H7 (E. coli O157:H7) is an important pathogenic bacterium that threatens human health. A rapid, simple, highly sensitive, and specific method for the detection of E. coli O157:H7 is necessary.

Methods

In the present study, immunomagnetic nanoparticles (IMPs) were prepared with nanopure iron as the core, coated with E. coli O157:H7 polyclonal antibodies. These IMPs were used in combination with immunochromatographic assay (ICA) and used to establish highly sensitive and rapid kits (IMPs+ICA) to detect E. coli O157:H7. The kits were then used to detect E. coli O157:H7 in 150 food samples and were compared with conventional ICA to evaluate their efficacy.

Results

The average diameter of IMPs was 56 nm and the amount of adsorbed antibodies was 106.0 μg/mg. The sensitivity of ICA and IMPs+ICA was 105 colony-forming units/mL and 103 CFUs/mL, respectively, for purified E. coli O157:H7 solution. The sensitivity of IMPs+ICA was increased by two orders, and its specificity was similar to ICA.

Conclusion

The kits have the potential to offer important social and economic benefits in the screening, monitoring, and control of food safety.

Background

Depletion of the circulating actin-binding protein, plasma gelsolin (pGSN) has been described in critically ill surgical patients. We hypothesized that the extent of pGSN reduction might correlate with different outcome of burn patients. The study was performed to evaluate the prognostic implications of pGSN levels on the development of multiple organ dysfunction syndrome (MODS) and fatal outcome in a group of severely burn patients.

Methods and Findings

95 patients were included, and they were divided into three groups with different burn area: group I (n = 33), group II (n = 32) and group III (n = 30). According to whether there was development of MODS or not, patients were divided into MODS group (n = 28) and none-MODS group (n = 67); then the patients with MODS were further divided into non-survivor group (n = 17) and survivor group (n = 11). The peripheral blood samples were collected on postburn days (PBD) 1, 3, 7, 14, and 21. The levels of pGSN were determined and T cells were procured from the blood. The contents of cytokines (IL-2, IL-4 and IFN-γ) released by T cells were also measured. The related factors of prognosis were analyzed by using multivariate logistic regression analysis. The results showed that pGSN concentrations, as well as the levels of IL-2 and IFN-γ, decreased markedly on PBD 1–21, whereas, the levels of IL-4 increased markedly in all burn groups as compared with normal controls (P<0.05 or P<0.01), and there were obviously differences between group I and group III (P<0.05 or P<0.01). The similar results were found in MODS patients and the non-survivor group as compared with those without MODS and the survival group on days 3–21 postburn (P<0.05 or P<0.01). Moreover, as the pGSN levels decreased, the incidence of septic complication as well as MODS remarkably increased.

Conclusions

pGSN levels appear to be an early prognostic marker in patients suffering from major burns.

Fe3O4 particles are currently used as the core of immunomagnetic microspheres in the immunomagnetic enrichment assay of circulating tumor cells (CTCs). It is difficult to further improve the sensitivity of CTC detection or to improve tumor cell-type identification and characterization. In the present study, we prepared immunomagnetic nanoparticles with nanopure iron as the core, coated with anti-cytokeratin 7/8 (CK7/8) monoclonal antibody. These immunomagnetic nanoparticles (IMPs) were used in conjunction with immunocytochemistry (ICC) to establish a refined immunomagnetic nanoparticle enrichment assay for CTC detection in non-small cell lung cancer (NSCLC). The assay was compared with nested reverse transcription polymerase chain reaction (RT-PCR) to detect CK19 mRNA and lung specific X protein (LUNX) mRNA. Human lung adenocarcinoma cell line A549 was used for sensitivity and specificity evaluation. Peripheral blood samples were collected from each group for CTC detection. The average diameter of the immunomagnetic nanoparticles was 51 nm, and the amount of adsorbed antibodies was 111.2 μg/mg. We could detect down to one tumor cell in 5 × 107 peripheral blood mononuclear cells. The sensitivity was consistent with that of nested RT-PCR; however, the false positive rate was significantly reduced. The modified assay combined with ICC did not differ from nested RT-PCR in sensitivity, but it had significantly increased specificity. This approach could, therefore, contribute to identification of micrometastases, re-defining clinical staging, and guiding individual postoperative treatments. The technique shows considerable potential clinical value and further clinical trials are warranted.

AIM: To investigate the inhibitory role and the underlying mechanisms of sorafenib on signal transducer and activator of transcription 3 (STAT3) activity in hepatocellular carcinoma (HCC).

METHODS: Human and rat HCC cell lines were treated with sorafenib. Proliferation and STAT3 dephosphorylation were assessed. Potential molecular mechanisms of STAT3 pathway inhibition by sorafenib were evaluated. In vivo antitumor action and STAT3 inhibition were investigated in an immunocompetent orthotopic rat HCC model.

RESULTS: Sorafenib decreased STAT3 phosphorylation at the tyrosine and serine residues (Y705 and S727), but did not affect Janus kinase 2 (JAK2) and phospha-tase shatterproof 2 (SHP2), which is associated with growth inhibition in HCC cells. Dephosphorylation of S727 was associated with attenuated extracellular signal-regulated kinase (ERK) phosphorylation, similar to the effects of a mitogen-activated protein kinase (MEK) inhibitor U0126, suggesting that sorafenib induced S727 dephosphorylation by inhibiting MEK/ERK signaling. Meanwhile, sorafenib could also inhibit Akt phosphorylation, and both the phosphatidylinositol-3-kinase (PI3K) inhibitor LY294002 and Akt knockdown resulted in Y705 dephosphorylation, indicating that Y705 dephosphorylation by sorafenib was mediated by inhibiting the PI3K/Akt pathway. Finally, in the rat HCC model, sorafenib significantly inhibited STAT3 activity, reducing tumor growth and metastasis.

CONCLUSION: Sorafenib inhibits growth and metastasis of HCC in part by blocking the MEK/ERK/STAT3 and PI3K/Akt/STAT3 signaling pathways, but independent of JAK2 and SHP2 activation.

In the crystal structure of the title compound, C5H5NO3, all the non-H atoms are approximately coplanar: the carb­oxy O atoms deviating by 0.013 (2) and −0.075 (2) Å from the isoxazole ring plane. In the crystal, the molecules form inversion dimers linked by pairs of O—H⋯O hydrogen bonds and the dimers stack via π–π inter­actions [centroid–centroid distance = 3.234 (2) Å].

Background

Population health attributes (such as disease incidence and prevalence) are often estimated using sentinel hospital records, which are subject to multiple sources of uncertainty. When applied to these health attributes, commonly used biased estimation techniques can lead to false conclusions and ineffective disease intervention and control. Although some estimators can account for measurement error (in the form of white noise, usually after de-trending), most mainstream health statistics techniques cannot generate unbiased and minimum error variance estimates when the available data are biased.

Methods and Findings

A new technique, called the Biased Sample Hospital-based Area Disease Estimation (B-SHADE), is introduced that generates space-time population disease estimates using biased hospital records. The effectiveness of the technique is empirically evaluated in terms of hospital records of disease incidence (for hand-foot-mouth disease and fever syndrome cases) in Shanghai (China) during a two-year period. The B-SHADE technique uses a weighted summation of sentinel hospital records to derive unbiased and minimum error variance estimates of area incidence. The calculation of these weights is the outcome of a process that combines: the available space-time information; a rigorous assessment of both, the horizontal relationships between hospital records and the vertical links between each hospital's records and the overall disease situation in the region. In this way, the representativeness of the sentinel hospital records was improved, the possible biases of these records were corrected, and the generated area incidence estimates were best linear unbiased estimates (BLUE). Using the same hospital records, the performance of the B-SHADE technique was compared against two mainstream estimators.

Conclusions

The B-SHADE technique involves a hospital network-based model that blends the optimal estimation features of the Block Kriging method and the sample bias correction efficiency of the ratio estimator method. In this way, B-SHADE can overcome the limitations of both methods: Block Kriging's inadequacy concerning the correction of sample bias and spatial clustering; and the ratio estimator's limitation as regards error minimization. The generality of the B-SHADE technique is further demonstrated by the fact that it reduces to Block Kriging in the case of unbiased samples; to ratio estimator if there is no correlation between hospitals; and to simple statistic if the hospital records are neither biased nor space-time correlated. In addition to the theoretical advantages of the B-SHADE technique over the two other methods above, two real world case studies (hand-foot-mouth disease and fever syndrome cases) demonstrated its empirical superiority, as well.