Atom counting from a combination of two ADF STEM images

To understand the structure-property relationship of nanostructures, reliably quantifying parameters, such as the number of atoms along the projection direction, is important. Advanced statistical methodologies have made it possible to count the number of atoms for monotype crystalline nanoparticles from a single ADF STEM image. Recent developments enable one to simultaneously acquire multiple ADF STEM images. Here, we present an extended statistics-based method for atom counting from a combination of multiple statistically independent ADF STEM images reconstructed from non-overlapping annular detector collection regions which improves the accuracy and allows one to retrieve precise atom-counts, especially for images acquired with low electron doses and multiple element structures.

C4 leaf development and evolution

C4 photosynthesis is more efficient than C3 photosynthesis for two reasons. First, C4 plants have evolved efficient C4 enzymes to suppress wasteful photorespiration and enhance CO2 fixation. Second, C4 leaves have Kranz anatomy in which the veins are surrounded by one layer of bundle sheath (BS) cells and one layer of mesophyll (M) cells. The BS and M cells are functionally well differentiated and also well coordinated for rapid assimilation of atmospheric CO2 and transport of photo-assimilates between the two types of cells. Recent comparative transcriptomics of developing M and BS cells in young maize embryonic leaves revealed not only potential regulators of BS and M cell differentiation but also rapid early BS cell differentiation whereas slower, more prolonged M cell differentiation, contrary to the traditional view of a far simpler process of M cell development. Moreover, new upstream regulators of Kranz anatomy development have been identified and a number of gene co-expression modules for early vascular development have been inferred. Also, a candidate gene regulatory network associated with Kranz anatomy and vascular development has been constructed. Additionally, how whole genome duplication (WGD) may facilitate C4 evolution has been studied and the reasons for why the same WGD event led to successful C4 evolution in Gynandropsis gynandra but not in the sister species Tarenaya hassleriana have been proposed. Finally, new future research directions are suggested.

[Long-term survival analysis of 1 367 patients treated with radical nephrectomy from a single center]

Objective: To report the long-term survival of renal cell carcinoma (RCC) patients treated with radical nephrectomy in Sun Yat-sen University Cancer Center. Methods: We retrospectively analyzed the clinical, pathological and follow-up records of 1 367 non-metastatic RCC patients treated with radical nephrectomy from 1999 to 2020 in this center. The primary endpoint of this study was overall survival rate. Survival curves were estimated using the Kaplan-Meier method, and group differences were compared through Log-rank test. Univariate and multivariate Cox analysis were fit to determine the clinical and pathological features associated with overall survival rate. Results: A total of 1 367 patients treated with radical nephrectomy with complete follow-up data were included in the study. The median follow-up time was 52.6 months, and 1 100 patients survived and 267 died, with the median time to overall survival not yet reached. The 5-year and 10-year overall survival rates were 82.8% and 74.9%, respectively. The 5-year and 10-year overall survival rates of Leibovich low-risk patients were 93.3% and 88.2%, respectively; of Leibovich intermediate-risk patients were 82.2% and 72.3%, respectively; and of Leibovich high-risk patients were 50.5% and 30.2%, respectively. There were significant differences in the long-term survival among the three groups (P<0.001). The 10-year overall survival rates for patients with pT1, pT2, pT3 and pT4 RCC were 83.2%, 73.6%, 55.0% and 31.4%, respectively. There were significant differences among pT1, pT2, pT3 and pT4 patients(P<0.001). The 5-year and 10-year overall survival rates of patients with lymph node metastasis were 48.5% and 35.6%, respectively, and those of patients without lymph node metastasis were 85.1% and 77.5%, respectively. There was significant difference in the long-term survival between patients with lymph node metastasis and without lymph node metastasis. The 10-year overall survival rate was 96.2% for nuclear Grade 1, 81.6% for nuclear Grade 2, 60.5% for nuclear Grade 3, and 43.4% for nuclear Grade 4 patients. The difference was statistically significant. There was no significant difference in the long-term survival between patients with localized renal cancer (pT1-2N0M0) who underwent open surgery and minimally invasive surgery (10-year overall survival rate 80.5% vs 85.6%, P=0.160). Multivariate Cox analysis showed that age≥55 years (HR=2.11, 95% CI: 1.50-2.96, P<0.001), T stage(T3+ T4 vs T1a: HR=2.37, 95% CI: 1.26-4.46, P=0.008), local lymph node metastasis (HR=3.04, 95%CI: 1.81-5.09, P<0.001), nuclear grade (G3-G4 vs G1: HR=4.21, 95%CI: 1.51-11.75, P=0.006), tumor necrosis (HR=1.66, 95% CI: 1.17-2.37, P=0.005), sarcomatoid differentiation (HR=2.39, 95% CI: 1.31-4.35, P=0.005) and BMI≥24kg/m(2) (HR=0.56, 95%CI: 0.39-0.80, P=0.001) were independent factors affecting long-term survival after radical nephrectomy. Conclusions: The long-term survival of radical nephrectomy in patients with renal cell carcinoma is satisfactory. Advanced age, higher pathological stage and grade, tumor necrosis and sarcomatoid differentiation were the main adverse factors affecting the prognosis of patients. Higher body mass index was a protective factor for the prognosis of patients.

[Establishment and validation of a novel nomogram to predict overall survival after radical nephrectomy]

Objective: To establish a nomogram prognostic model for predicting the 5-, 10-, and 15-year overall survival (OS) of non-metastatic renal cell carcinoma patients managed with radical nephrectomy (RN), compare the modelled results with the results of pure pathologic staging, the Karakiewicz nomogram and the Mayo Clinic Stage, Size, Grade, and Necrosis (SSIGN) score commonly used in foreign countries, and stratify the patients into different prognostic risk subgroups. Methods: A total of 1 246 non-metastatic renal cell carcinoma patients managed with RN in Sun Yat-sen University Cancer Center (SYSUCC) from 1999 to 2020 were retrospectively analyzed. Multivariate Cox regression analysis was used to screen the variables that influence the prognosis for nomogram establishment, and the bootstrap random sampling was used for internal validation. The time-receiver operating characteristic curve (ROC), the calibration curve and the clinical decision curve analysis (DCA) were applied to evaluate the nomogram. The prediction efficacy of the nomogram and that of the pure pathologic staging, the Karakiewicz nomogram and the SSIGN score was compared through the area under the curve (AUC). Finally, patients were stratified into different risk subgroups according to our nomogram scores. Results: A total of 1 246 patients managed with RN were enrolled in this study. Multivariate Cox regression analysis showed that age, smoking history, pathological nuclear grade, sarcomatoid differentiation, tumor necrosis and pathological T and N stages were independent prognostic factors for RN patients (all P<0.05). A nomogram model named SYSUCC based on these factors was built to predict the 5-, 10-, and 15-year survival rate of the participating patients. In the bootstrap random sampling with 1 000 iterations, all these factors occurred for more than 800 times as independent predictors. The Harrell's concordance index (C-index) of SYSUCC was higher compared with pure pathological staging [0.770 (95% CI: 0.716-0.823) vs 0.674 (95% CI: 0.621-0.728)]. The calibration curve showed that the survival rate as predicted by the SYSUCC model simulated the actual rate, while the clinical DCA showed that the SYSUCC nomogram has a benefit in certain probability ranges. In the ROC analysis that included 857 patients with detailed pathological nuclear stages, the nomogram had a larger AUC (5-/10-year AUC: 0.823/0.804) and better discriminating ability than pure pathological staging (5-/10-year AUC: 0.701/0.658), Karakiewicz nomogram (5-/10-year AUC: 0.772/0.734) and SSIGN score (5-/10-year AUC: 0.792/0.750) in predicting the 5-/10-year OS of RN patients (all P<0.05). In addition, the AUC of the SYSUCC nomogram for predicting the 15-year OS (0.820) was larger than that of the SSIGN score (0.709), and there was no statistical difference (P<0.05) between the SYSUCC nomogram, pure pathological staging (0.773) and the Karakiewicz nomogram (0.826). The calibration curve was close to the standard curve, which indicated that the model has good predictive performance. Finally, patients were stratified into low-, intermediate-, and high-risk subgroups (738, 379 and 129, respectively) according to the SYSUCC nomogram scores, among whom patients in intermediate- and high-risk subgroups had a worse OS than patients in the low-risk subgroup (intermediate-risk group vs. low-risk group: HR=4.33, 95% CI: 3.22-5.81, P<0.001; high-risk group vs low-risk group: HR=11.95, 95% CI: 8.29-17.24, P<0.001), and the high-risk subgroup had a worse OS than the intermediate-risk group (HR=2.63, 95% CI: 1.88-3.68, P<0.001). Conclusions: Age, smoking history, pathological nuclear grade, sarcomatoid differentiation, tumor necrosis and pathological stage were independent prognostic factors for non-metastasis renal cell carcinoma patients after RN. The SYSUCC nomogram based on these independent prognostic factors can better predict the 5-, 10-, and 15-year OS than pure pathological staging, the Karakiewicz nomogram and the SSIGN score of patients after RN. In addition, the SYSUCC nomogram has good discrimination, agreement, risk stratification and clinical application potential.

Histone H3K27 demethylase UTX compromises articular chondrocyte anabolism and aggravates osteoarthritic degeneration

Epigenome alteration in chondrocytes correlates with osteoarthritis (OA) development. H3K27me3 demethylase UTX regulates tissue homeostasis and deterioration, while its role was not yet studied in articulating joint tissue in situ. We now uncovered that increased UTX and H3K27me3 expression in articular chondrocytes positively correlated with human knee OA. Forced UTX expression upregulated the H3K27me3 enrichment at transcription factor Sox9 promoter, inhibiting key extracellular matrix molecules collagen II, aggrecan, and glycosaminoglycan in articular chondrocytes. Utx overexpression in knee joints aggravated the signs of OA, including articular cartilage damage, synovitis, osteophyte formation, and subchondral bone loss in mice. Chondrocyte-specific Utx knockout mice developed thicker articular cartilage than wild-type mice and showed few gonarthrotic symptoms during destabilized medial meniscus- and collagenase-induced joint injury. In vitro, Utx loss changed H3K27me3-binding epigenomic landscapes, which contributed to mitochondrial activity, cellular senescence, and cartilage development. Insulin-like growth factor 2 (Igf2) and polycomb repressive complex 2 (PRC2) core components Eed and Suz12 were, among others, functional target genes of Utx. Specifically, Utx deletion promoted Tfam transcription, mitochondrial respiration, ATP production and Igf2 transcription but inhibited Eed and Suz12 expression. Igf2 blockade or forced Eed or Suz12 expression increased H3K27 trimethylation and H3K27me3 enrichment at Sox9 promoter, compromising Utx loss-induced extracellular matrix overproduction. Taken together, UTX repressed articular chondrocytic activity, accelerating cartilage loss during OA. Utx loss promoted cartilage integrity through epigenetic stimulation of mitochondrial biogenesis and Igf2 transcription. This study highlighted a novel noncanonical role of Utx, in concert with PRC2 core components, in controlling H3K27 trimethylation and articular chondrocyte anabolism and OA development.

Single-cell transcriptomics reveals a low CD8+ T cell infiltrating state mediated by fibroblasts in recurrent renal cell carcinoma

Purpose

Recurrent renal cell carcinoma(reRCC) is associated with poor prognosis and the underlying mechanism is not yet clear. A comprehensive understanding of tumor microenvironment (TME) of reRCC may aid in designing effective anticancer therapies, including immunotherapies. Single-cell transcriptomics holds great promise for investigating the TME, however, this technique has not been used in reRCC. Here, we aimed to explore the difference in the TME and gene expression pattern between primary RCC (pRCC) and reRCC at single-cell level.

Experimental design

We performed single-cell RNA sequencing analyses of 32,073 cells from 2 pRCC, 2 reRCC, and 3 adjacent normal kidney samples. 41 pairs of pRCC and reRCC samples were collected as a validation cohort to assess differences observed in single-cell sequencing. The prognostic significance of related cells and markers were studied in 47 RCC patients underwent immunotherapy. The function of related cells and markers were validated via in vitro and in vivo experiments.

Results

reRCC had reduced CD8⁺ T cells but increased cancer-associated fibroblasts (CAFs) infiltration compared with pRCC. Reduced CD8⁺ T cells and increased CAFs infiltration were significantly associated with a worse response from immunotherapy. Remarkably, CAFs showed substantial expression of LGALS1 (Gal1). In vitro, CAFs could induce CD8⁺ T cells apoptosis via Gal1. In vivo, knockdown of Gal1 in CAFs suppressed tumor growth, increased CD8⁺ T cells infiltration, reduced the proportion of apoptotic CD8⁺ T cells and enhanced the efficacy of immunotherapy.

Conclusions

We delineated the heterogeneity of reRCC and highlighted an innovative mechanism that CAFs acted as a suppressor of CD8⁺ T cells via Gal1. Targeting Gal1 combined with anti-PD1 showed promising efficacy in treating RCC.

LRPPRC regulates redox homeostasis via the circANKHD1/FOXM1 axis to enhance bladder urothelial carcinoma tumorigenesis

Reactive oxygen species (ROS) which are continuously generated mainly by mitochondria, have been proved to play an important role in the stress signaling of cancer cells. Moreover, pentatricopeptide repeat (PPR) proteins have been suggested to take part in mitochondrial metabolism. However, the mechanisms integrating the actions of these distinct networks in urothelial carcinoma of the bladder (UCB) pathogenesis are elusive. In this study, we found that leucine rich pentatricopeptide repeat containing (LRPPRC) was frequently upregulated in UCB and that it was an independent prognostic factor in UCB. We further revealed that LRPPRC promoted UCB tumorigenesis by regulating the intracellular ROS homeostasis. Mechanistically, LRPPRC modulates ROS balance and protects UCB cells from oxidative stress via mt-mRNA metabolism and the circANKHD1/FOXM1 axis. In addition, the SRA stem-loop interacting RNA binding protein (SLIRP) directly interacted with LRPPRC to protect it from ubiquitination and proteasomal degradation. Notably, we showed that LRPPRC modulated the tumorigenesis of UCB cells in a circANKHD1-FOXM1-dependent manner. In conclusion, LRPPRC exerts critical roles in regulating UCB redox homeostasis and tumorigenesis, and is a prognostic factor for UCB; suggesting that LRPPRC may serve as an exploitable therapeutic target in UCB.

Ureteral stents cannot decrease the incidence of ureteroileal anastomotic stricture and leakage: A systematic review and meta-analysis

BACKGROUND

The ileal conduit and ileal orthotopic neobladder were the most popular methods for urinary diversion following radical cystectomy. Stenting the anastomosis of ileo-ureter or ureter-neobladder was a common practice. However, it is still controversial if ureteral stents could prevent complications such as ureteroileal anastomosis stricture (UIAS) and ureteroileal anastomosis leakage (UIAL) after ureteral anastomosis.

OBJECTIVES

This study aims to investigate the role of the ureteral stent in preventing UIAS and UIAL.

DATA SOURCES

We systematically searched the related studies in PubMed, Embase, and Cochrane Library up to June 2020.

STUDY ELIGIBILITY CRITERIA

Cohort studies that identified the use of stent and the incidence of UIAS or UIAL were recorded.

DATA SYNTHESIS

Comparative meta-analysis was conducted on four cohort studies for comparison of UIAS and UIAL between the stented and nonstented groups. Besides, eleven studies which reported the events of UIAS and UIAL were used for meta-analysis of single proportion.

RESULTS

A total of 11 studies were qualified for analysis. Comparative meta-analysis identified that the incidence of UIAS was higher in the stented group than that in the nonstented group, but this did not reach a significant difference (odds ratio [OR]: 1.64; 95% confidence interval [CI]: 0.88-3.05; P = 0.12). Besides, there was no difference in the incidences of UIAL between the stented and the nonstented groups. On meta-analysis of single proportion, the incidence of UIAS was 7% (95% CI: 3%-10%) in the stented group and 3% (95% CI: 1%-6%) in the nonstented group. The UIAL rate was 1% (95% CI, 0%-4%) in stented patients and 2% (95% CI, 1%-4%) in nonstented patients.

CONCLUSION

Stenting the ureteroileal anastomosis resulted in a higher incidence of UIAS. There is no evidence to support ureteral stents could prevent the occurrence of UIAL after urinary diversion.

Rice transcription factor GAMYB modulates bHLH142 and is homeostatically regulated by TDR during anther tapetal and pollen development

GIBBERELLIN MYB GENE (GAMYB), UNDEVELOPED TAPETUM1 (UDT1), TDR INTERACTING PROTEIN2 (TIP2/bHLH142), TAPETUM DEGENERATION RETARDATION (TDR), and ETERNAL TAPETUM 1/DELAYED TAPETUM DEGENERATION (EAT1/DTD) are important transcription factors that play a crucial role during pollen development in rice. This study demonstrates that bHLH142 acts downstream of UDT1 and GAMYB and works as a 'hub' in these two pollen pathways. We show that GAMYB modulates bHLH142 expression through specific binding to the MYB motif of the bHLH142 promoter during the early stage of pollen development, while TDR acts as a transcriptional repressor of the GAMYB modulation of bHLH142 by binding to the E-box close to the MYB motif on the promoter. Altered expression of these transcription factors highlights that a tight, precise, and coordinated regulation among them is essential for normal pollen development. Most notably, we show that the regulatory pathways of GAMYB and UDT1 rely on bHLH142 in a direct and indirect manner, respectively, and function in different tissues with distinct biological roles during pollen development. This study advances our understanding of the molecular mechanisms of rice pollen development.

[The study of the protection function of the sphingosine kinase 1 in the nerve cell damage caused by acrylamide]

Objective: To study the protective effect and effect of SphK1 overexpression on the injury of nerve cells induced by acrylamide. Methods: ACR with 99% purity was prepared into 1.25 mmol/L and 2.5 mmol/L solutions. SH-SY5Y cells were divided into control group (NC group) , experimental group and SphK1 activator group. The experimental group was given ACR solution with final concentration of 1.25 mmol/L and 2.5 mmol/L respectively for 24 h. In the SphK1 activator group, on the basis of the exposure concentration of the experimental group, the SphK1 specific activator (12-) phorbol tetradecanoate (-13-) acetate (PMA) solution[prepared by dimethyl sulfoxide (DMSO) , the final concentration was 100 nmol/l], and other treatments were the same as the experimental group. Control group (NC group) added PMA solution into normal cells. Western blot was used to detect the expression of SphK1 protein; CCK-8 was used to detect the proliferation of SH-SY5Y cells; hoechst33342 method was used to observe the morphological changes of nerve cells; flow cytometry was used to analyze the apoptosis of cells. Results: Compared with NC group, the expression of SphK1 protein in the experimental group and the SphK1 activator group was significantly lower (P<0.05) . Compared with the experimental group, the expression of SphK1 protein in each concentration of SphK1 activator group was increased, and the difference was statistically significant (P<0.05) . In addition to 1.25 mmol/L SphK1 activator group, compared with NC group, the relative growth survival rate of experimental group and 2.5 mmol/L SphK1 activator group were lower, the difference was statistically significant (P<0.05) . Compared with the experimental group, the relative survival rate of cells in the SphK1 activator group was higher, and the difference was statistically significant (P<0.05) . With the increase of exposure concentration, the cells in the experimental group showed the morphological characteristics of early apoptosis at ACR 1.25 mmol/L and late apoptosis at ACR 2.5 mmol/L. Compared with NC group, the apoptosis rate of experimental group and SphK1 activator group at ACR 2.5 mmol/L was significantly different (P<0.05) ; compared with experimental group, the apoptosis rate of SphK1 activator group at ACR 2.5 mmol/L was lower, the difference was statistically significant (P<0.05) . Conclusion: The SphK1 excessive expression plays the protective function to the nerve cell damage caused by acrylamide.

Prognostic significance of tumor-infiltrating immune cells in muscle-invasive bladder cancer

BACKGROUND

Muscle-invasive bladder cancer (MIBC) is a lethal disease with poor treatment response and a high death rate. Immune cells infiltrating the tumor tissues have been shown to play a vital role in tumorigenesis and tumor progression, but their prognostic significance in MIBC remains unclear.

OBJECTIVES

To explore the landscape and prognostic significance of tumor-infiltrating immune cells (TIICs) in MIBC, and to develop a model to improve the prognostic predictions of MIBC.

METHODS AND MATERIALS

The gene expression profile and clinical data of MIBC patients were downloaded from the Gene Expression Omnibus and The Cancer Genome Atlas portal. The fractions of 22 TIIC subtypes were calculated using the Cell Type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) algorithm. A TIICs-based model was constructed using least absolute shrinkage and selection operator (LASSO) Cox regression in a training cohort and validated in the validation cohort.

RESULTS

Ten types of TIICs demonstrated different infiltration abundance between MIBC and normal tissue. We also found 11 types of TIICs that were significantly associated with overall survival (OS). A TIICs-based model was established, consisting of 15 types of immune cells, and an immunoscore was calculated. Significant differences in OS were found between the high and low immunoscore groups, in both training (n = 343) and validation (n = 146) cohorts. The model could identify patients who would have worse OS despite having similar clinical characteristics. Furthermore, multivariate analysis identified the immunoscore as an independent risk factor (hazard ratio, 3.23; 95% confidence interval; 2.22-4.70) for OS in MIBC patients.

CONCLUSION

The landscape of immune infiltration is different between MIBC and normal tissue. The TIICs-based model could provide promising predictive value to complement the existing staging system for predicting the OS of MIBC patients.

[Clinical characteristics in patients with hypervirulent Klebsiella pneumoniae infection and its capsular serotypes and multilocus sequence typing]

Objective: To describe the clinical characteristics of hypervirulent Klebsiella pneumoniae (hvKP) infection. To analyze the antibiotic susceptibility of hvKP to provide the empiric antibiotic options. To investigate capsule serotype and sequence type (ST) of hvKP and their correlation with clinical profiles. Methods: hvKP was defined as bacteria isolated from patients with community-acquired pyogenic liver abscess (CA-PLA) with co-infection sites outside liver or a bloodstream infection in a host without underlying biliary tract diseases. Patients with CA-PLA hospitalized in the First Hospital of China Medical University were retrospectively analyzed from January 2011 to December 2017. Antibiotic susceptibility was detected by automatic bacterial identification and antibiotic susceptibility analysis system in vitro. Polymerase chain reaction method and gene sequencing were used to detect the main capsule serotype and ST. Results: A total of 140 cases with hvKP infection were enrolled. The co-infections outside liver abscess included 98 bloodstream infections, 53 pneumonia, 11 perianal abscess, 10 urinary system infections, 3 subphrenic abscess, 3 endophthalmitis, 2 spleen abscess, and other miscellaneous infections including 1 peritonitis, 1 skin and soft tissue infection, 1 myelitis, 1 colitis, 1 psoas major abscess and 1 myocardial abscess. Among the 140 cases, 106 presented with single co-infection site, 32 with 2 sites, and 2 with 3 sites. HvKP manifested high antibiotic susceptibility up to 80% for most commonly used antibiotics. Capsule serotyping of 43 revived isolates indicated that K1 serotype accounted for 53.49% (23/43), K2 34.88 (15/43), K54 2.33% (1/43), K57 2.33% (1/43), and other serotypes 6.98%(3/43). There was no significant distribution among K1, K2, K54 and K57 of hvKP capsule serotypes in patients with or without diabetes mellitus (P>0.05). Multilocus sequence typing (MLST) suggested that ST23 and ST65 were predominant accounting for 39.53% (17/43) and 25.58% (11/43) respectively. No serotype or ST predominance was seen in any of the clinical infections. Conclusion: HvKP is related to a wide spectrum of infectious diseases, including multiple extrahepatic sites and bloodstream infections besides CA-PLA with high antibiotic susceptibility. K1 and K2 are the predominant capsule serotypes, and ST 23 and ST65 are the predominant sequence types.

Popmarker: Identifying Phylogenetic Markers at the Population Level

As phylogenomic approach becomes a common practice for constructing true bacterial phylogenies, it has become apparent that single molecular markers such as 16S ribosomal DNA often lead to misclassification of species. In this study, we present a program called Popmarker that uses the true species phylogeny and identifies a minimum set of molecular markers reflecting the bacterial evolution history and phylogenetic relationship at the resolution of populations. Popmarker ranks the proteome according to the correlation of whole species tree or subtree branch length against orthologous sequence distances. We demonstrate that 5 proteins of 2 top ranks achieve the same resolution as concatenation of 2203 single-copy orthologous genes and the right species classification as well as correct split of the 2 groups of Vibrio campbellii . The top-ranking genes selected by Popmarker are candidates that lead to speciation and are useful in distinguishing close related species in microbiome study.

Elevated auxin biosynthesis and transport underlie high vein density in C4 leaves

High vein density, a distinctive trait of C4 leaves, is central to both C3-to-C4 evolution and conversion of C3 to C4-like crops. We tested the hypothesis that high vein density in C4 leaves is due to elevated auxin biosynthesis and transport in developing leaves. Up-regulation of genes in auxin biosynthesis pathways and higher auxin content were found in developing C4 leaves compared with developing C3 leaves. The same observation held for maize foliar (C4) and husk (C3) leaf primordia. Moreover, auxin content and vein density were increased in loss-of-function mutants of Arabidopsis MYC2, a suppressor of auxin biosynthesis. Treatment with an auxin biosynthesis inhibitor or an auxin transport inhibitor led to much fewer veins in new leaves. Finally, both Arabidopsis thaliana auxin efflux transporter pin1 and influx transporter lax2 mutants showed reduced vein numbers. Thus, development of high leaf vein density requires elevated auxin biosynthesis and transport.

[Recombinant human tumor necrosis factor receptor type Ⅱ-IgG Fc fusion protein for treatment of occupational medicamentosa-like dermatitis induced by trichloroethylene]

Objective: To investigate the efficacy and safety of the recombinant human tumor necrosis factor receptor Ⅱ-IgG Fc fusion protein (rhTNFR: Fc, etanercept) for the treatment of occupational medicamentosa-like dermatitis induced by trichloroethylene (OMLDT) . Methods: In September 2011 to February 2016, 12 patients with OMLDT were treated with etanercept 25 mg, subcutaneous injection, twice per week, doubling of first dose. The course of treatment was 6 weeks. The drug eruption area and severity index (DASI) score, the proportion of patients achieving a 50%, 75% and 90% reduction in DASI (DASI50, DASI75, DASI90) and the serum level of TNF-α were used to assess the efficacy at different times. Adverse reactions were also recorded and evaluated. The results were statistically analyzed by nonparametric Friedman test and repetitive measurement ANOVA using the software SPSS19.0. Results: After 4 weeks treatment, the DASI score decreased form 56.33±7.02 to 0.50±0.91 (P<0.01) . The DASI50, DASI75 and DASI90 were all increased to 12 (100%) . The serum level of TNF-α decreased form (43.74±41.62) pg/ml to (3.03±0.47) pg/ml (P<0.01) . Statistically significant difference was observed from the above indexes. There were no adverse reactions in clinical application. Conclusion: Recombinant human tumor necrosis factor receptor Ⅱ-IgG Fc fusion protein may be a safe and effective drug in the treatment of OMLDT.

Exome Sequencing of Oral Squamous Cell Carcinoma Reveals Molecular Subgroups and Novel Therapeutic Opportunities

Oral squamous cell carcinoma (OSCC), an epithelial malignancy affecting a variety of subsites in the oral cavity, is prevalent in Asia. The survival rate of OSCC patients has not improved over the past decades due to its heterogeneous etiology, genetic aberrations, and treatment outcomes. Improvement in therapeutic strategies and tailored treatment options is an unmet need. To unveil the mutational spectrum, whole-exome sequencing of 120 OSCC from male individuals in Taiwan was conducted. Analyzing the contributions of the five mutational signatures extracted from the dataset of somatic variations identified four groups of tumors that were significantly associated with demographic and clinical features. In addition, known (TP53, FAT1, EPHA2, CDKN2A, NOTCH1, CASP8, HRAS, RASA1, and PIK3CA) and novel (CHUK and ELAVL1) genes that were significantly and frequently mutated in OSCC were discovered. Further analyses of gene alteration status with clinical parameters revealed that the tumors of the tongue were enriched with copy-number alterations in several gene clusters containing CCND1 and MAP4K2. Through defining the catalog of targetable genomic alterations, 58% of the tumors were found to carry at least one aberrant event potentially targeted by US Food and Drug Administration (FDA)-approved agents. Strikingly, if targeting the p53-cell cycle pathway (TP53 and CCND1) by the drugs studied in phase I-III clinical trials, those possibly actionable tumors are predominantly located in the tongue, suggesting a better prediction of sensitivity to current targeted therapies. Our work revealed molecular OSCC subgroups that reflect etiological and prognostic correlation as well as defined the landscape of major altered events in the coding regions of OSCC genomes. These findings provide clues for the design of clinical trials for targeted therapies and stratification of OSCC patients with differential therapeutic efficacy.

Identification and evolutionary analysis of long non-coding RNAs in zebra finch

Background

Long non-coding RNAs (lncRNAs) are important in various biological processes, but very few studies on lncRNA have been conducted in birds. To identify IncRNAs expressed during feather development, we analyzed single-stranded RNA-seq (ssRNA-seq) data from the anterior and posterior dorsal regions during zebra finch (Taeniopygia guttata) embryonic development. Using published transcriptomic data, we further analyzed the evolutionary conservation of IncRNAs in birds and amniotes.

Results

A total of 1,081 lncRNAs, including 965 intergenic lncRNAs (lincRNAs), 59 intronic lncRNAs, and 57 antisense lncRNAs (lncNATs), were identified using our newly developed pipeline. These avian IncRNAs share similar characteristics with lncRNAs in mammals, such as shorter transcript length, lower exon number, lower average expression level and less sequence conservation than mRNAs. However, the proportion of lncRNAs overlapping with transposable elements in birds is much lower than that in mammals. We predicted the functions of IncRNAs based on the enriched functions of co-expressed protein-coding genes. Clusters of lncRNAs associated with natal down development were identified. The sequences and expression levels of candidate lncRNAs that shared conserved sequences among birds were validated by qPCR in both zebra finch and chicken. Finally, we identified three highly conserved lncRNAs that may be associated with natal down development.

Conclusions

Our study provides the first systematical identification of avian lncRNAs using ssRNA-seq analysis and offers a resource of embryonically expressed lncRNAs in zebra finch. We also predicted the biological function of identified lncRNAs.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-017-3506-z) contains supplementary material, which is available to authorized users.

Insights into the regulation of C4 leaf development from comparative transcriptomic analysis

C4 photosynthesis is more efficient than C3 photosynthesis for two reasons. First, C4 plants have evolved a repertoire of C4 enzymes to enhance CO2 fixation. Second, C4 leaves have Kranz anatomy with a high vein density in which the veins are surrounded by one layer of bundle sheath (BS) cells and one layer of mesophyll (M) cells. The BS and M cells are not only functionally well differentiated, but also well-coordinated for rapid transport of photo-assimilates between the two types of photosynthetic cells. Recent comparative transcriptomic and anatomical analyses of C3 and C4 leaves have revealed early onset of C4-related processes in leaf development, suggesting that delayed mesophyll differentiation contributes to higher C4 vein density, and have identified some candidate regulators for the higher vein density in C4 leaves. Moreover, comparative transcriptomics of maize husk (C3) and foliar leaves (C4) has identified a cohort of candidate regulators of Kranz anatomy development. In addition, there has been major progress in the identification of transcription factor binding sites, greatly increasing our knowledge of gene regulation in plants.

CARD9 mutation linked to Corynespora cassiicola infection in a Chinese patient

Corynespora cassiicola is a plant pathogen associated with leaf-spotting disease. The fungus has been found on diverse substrates: leaves, stems and roots of plants; nematode cysts and human skin. It rarely causes human infections. Here we report one case of subcutaneous phaeohyphomycosis caused by C. cassiicola with prominent tissue necrosis in a woman. All of her clinical features pointed towards a genetic linkage. Hence, whole-exome sequencing and Sanger sequencing were performed on this patient. One mutation of CARD9 was detected.

The importance of extranodal extension in penile cancer: a meta-analysis

Background

The role of extranodal extension (ENE) in penile cancer is controversial and has not been well studied. The aim of this study was to investigate the importance of ENE in predicting prognosis and presence of pelvic lymph node metastasis (PLNM) in penile cancer patients.

Methods

We searched related studies in Medline, Embase, Cochrane Library, and Scopus database. Hazard ratio (HR) and odds ratio (OR) were directly extracted or indirectly estimated from the included studies.

Results

A total of ten studies with 1,142 patients were included in this meta-analysis. Patients with ENE showed a worse cancer-specific survival (CSS) (HR = 1.90, 95 % confidence interval [CI] = 1.35–2.67, P = 0.0002) and overall survival (HR = 4.04, 95 % CI = 1.02–16.1, P = 0.05) than those without ENE. Further subgroup analysis revealed that the predictive value of ENE for CSS in penile cancer patients was significant regardless of the study’s country of origin, but not in the subgroup with shorter follow-up time (<36 months, P = 0.38). Patients with ENE also showed a higher incidence of presenting with PLNM (OR = 4.95, 95 % CI = 2.58–9.49, P < 0.001). A stratified analysis demonstrated that the predictive role of ENE for PLNM was only detected in studies with a larger sample size (> 100 cases). No significant publication bias was observed, as suggested by Begg’s and Egger’s tests.

Conclusions

ENE is associated with worse prognosis and high risk of PLNM in penile cancer patients. Due to the limited number of studies included in this meta-analysis, a large-scale, well-designed study will be required to verify our results.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-015-1834-4) contains supplementary material, which is available to authorized users.

Potential modulation on P-glycoprotein and CYP3A by soymilk and miso: in vivo and ex-vivo studies

P-glycoprotein (P-gp) and CYP3A4 both play very important roles in drug bioavailability, resistance and interactions. Our in vitro studies indicated that P-gp function was activated by many isoflavones. This study investigated the in vivo effects of soymilk and miso, isoflavone-rich soy foods, on P-gp and CYP3A by tracing the pharmacokinetics of cyclosporine (CSP), a probe drug of P-gp. Rats were orally administered CSP with and without soymilk or miso. A specific monoclonal fluorescence polarisation immunoassay was used to determine the blood concentration of CSP. The results showed that soymilk and miso significantly decreased the C(max) of CSP by 64.5% and 78.3%, and reduced the AUC(0-540) by 64.9% and 78.3%, respectively. Mechanism studies revealed that the activities of P-gp and CYP3A4 were induced by soymilk and miso. In conclusion, ingestion of soymilk and miso significantly activated the functions of P-gp and CYP3A.

Kidney-targeting Smad7 gene transfer inhibits renal TGF-β/MAD homologue (SMAD) and nuclear factor κB (NF-κB) signalling pathways, and improves diabetic nephropathy in mice

AIMS/HYPOTHESIS

The TGF-β/MAD homologue (SMAD) and nuclear factor κB (NF-κB) signalling pathways have been shown to play a critical role in the development of renal fibrosis and inflammation in diabetic nephropathy. We therefore examined whether targeting these pathways by a kidney-targeting Smad7 gene transfer has therapeutic effects on renal lesions in the db/db mouse model of type 2 diabetes.

METHODS

We delivered Smad7 plasmids into the kidney of db/db mice using kidney-targeting, ultrasound-mediated, microbubble-inducible gene transfer. The histopathology, ultrastructural pathology and pathways of TGF-β/SMAD2/3-mediated fibrosis and NF-κB-dependent inflammation were evaluated.

RESULTS

In this mouse model of type 2 diabetes, Smad7 gene therapy significantly inhibited diabetic kidney injury, compared with mice treated with empty vectors. Symptoms inhibited included: (1) proteinuria and renal function impairment; (2) renal fibrosis such as glomerular sclerosis, tubulo-interstitial collagen matrix abundance and renal inflammation, including Inos (also known as Nos2), Il1b and Mcp1 (also known as Ccl2) upregulation, as well as macrophage infiltration; and (3) podocyte and endothelial cell injury as demonstrated by immunohistochemistry and/or electron microscopy. Further study demonstrated that the improvement of type 2 diabetic kidney injury by overexpression of Smad7 was associated with significantly inhibited local activation of the TGF-β/SMAD and NF-κB signalling pathways in the kidney.

CONCLUSIONS/INTERPRETATION

Our results clearly demonstrate that kidney-targeting Smad7 gene transfer may be an effective therapy for type 2 diabetic nephropathy, acting via simultaneous modulation of the TGF-β/SMAD and NF-κB signalling pathways.

A rare case of the coexistence of ovarian clear cell carcinoma, mucinous cystadenoma, and endometriosis in the same ovary

Clear cell carcinomas and endometrioid carcinomas are associated with endometriosis. The association of clear cell carcinomas with mucinous lesions has only been reported infrequently, and with mucinous cystadenoma has been rarely reported. This is the second reported case of the coexistence of ovarian clear cell carcinoma, mucinous cystadenoma, and endometriosis in the same ovary. A 57-year-old woman presented with lower abdominal pain for three weeks. Ultrasonography revealed a 16 x 14 x 10 cm mass in the left ovary with solid and cystic components. Hysterectomy and bilateral salpingo-oophorectomy were performed. Histopathological examination of the left ovary revealed the presence of clear cell carcinoma, mucinous cystadenoma, and endometriosis. Continuity between the areas of mucinous epithelium and clear cell carcinoma were noted; this may suggest that clear cell carcinoma may arise from endometriosis or mucinous cystic tumors.

From laws of inference to protein folding dynamics

Protein folding dynamics is one of major issues constantly investigated in the study of protein functions. The molecular dynamic (MD) simulation with the replica exchange method (REM) is a common theoretical approach considered. Yet a trade-off in applying the REM is that the dynamics toward the native configuration in the simulations seems lost. In this work, we show that given REM-MD simulation results, protein folding dynamics can be directly derived from laws of inference. The applicability of the resulting approach, the entropic folding dynamics, is illustrated by investigating a well-studied Trp-cage peptide. Our results are qualitatively comparable with those from other studies. The current studies suggest that the incorporation of laws of inference and physics brings in a comprehensive perspective on exploring the protein folding dynamics.

The polycomb group protein Bmi-1 represses the tumor suppressor PTEN and induces epithelial-mesenchymal transition in human nasopharyngeal epithelial cells

The polycomb group protein B lymphoma Mo-MLV insertion region 1 homolog (Bmi-1) is dysregulated in various cancers, and its upregulation strongly correlates with an invasive phenotype and poor prognosis in patients with nasopharyngeal carcinomas. However, the underlying mechanism of Bmi-1-mediated invasiveness remains unknown. In the current study, we found that upregulation of Bmi-1 induced epithelial-mesenchymal transition (EMT) and enhanced the motility and invasiveness of human nasopharyngeal epithelial cells, whereas silencing endogenous Bmi-1 expression reversed EMT and reduced motility. Furthermore, upregulation of Bmi-1 led to the stabilization of Snail, a transcriptional repressor associated with EMT, via modulation of PI3K/Akt/GSK-3beta signaling. Chromatin immunoprecipitation assays revealed that Bmi-1 transcriptionally downregulated expression of the tumor suppressor PTEN in tumor cells through direct association with the PTEN locus. This in vitro analysis was consistent with the statistical inverse correlation detected between Bmi-1 and PTEN expression in a cohort of human nasopharyngeal carcinoma biopsies. Moreover, ablation of PTEN expression partially rescued the migratory/invasive phenotype of Bmi-1-silenced cells, indicating that PTEN might be a major mediator of Bmi-1-induced EMT. Our results provide functional and mechanistic links between the oncoprotein Bmi-1 and the tumor suppressor PTEN in the development and progression of cancer.

Upregulation of CENP-H in tongue cancer correlates with poor prognosis and progression

Background

Centromere protein H (CENP-H) is one of the fundamental components of the human active kinetochore. Recently, CENP-H was identified to be associated with tumorigenesis. This study was aimed to investigate the clinicopathologic significance of CENP-H in tongue cancer.

Methods

RT-PCR, real time RT-PCR and Western blot were used to examine the expression of CENP-H in tongue cancer cell lines and biopsies. CENP-H protein level in paraffin-embedded tongue cancer tissues were tested by immunohistochemical staining and undergone statistical analysis. CENP-H-knockdown stable cell line was established by infecting cells with a retroviral vector pSuper-retro-CENP-H-siRNA. The biological function of CENP-H was tested by MTT assay, colony formation assay, and Bromodeoxyuridine (BrdU) incorporation assay.

Results

CENP-H expression was higher in tongue cancer cell lines and cancer tissues (T) than that in normal cell and adjacent noncancerous tongue tissues (N), respectively. It was overexpressed in 55.95% (94/168) of the paraffin-embedded tongue cancer tissues, and there was a strong correlation between CENP-H expression and clinical stage, as well as T classification. CENP-H can predict the prognosis of tongue cancer patients especially those in early stage. Depletion of CENP-H can inhibit the proliferation of tongue cancer cells (Tca8113) and downregulate the expression of Survivin.

Conclusion

These findings suggested that CENP-H involves in the development and progression of tongue cancer. CENP-H might be a valuable prognostic indicator for tongue cancer patients within early stage.

Centromere protein H is a novel prognostic marker for human nonsmall cell lung cancer progression and overall patient survival

BACKGROUND

Lung cancer is 1 of the leading causes of cancer death worldwide, and the high mortality from this disease is caused mainly by the lack of efficient diagnostic strategies for early-stage lung cancer. The objective of the current study was to investigate the expression pattern and clinicopathologic significance of centromere protein H (CENP-H) in patients with nonsmall cell lung cancer (NSCLC).

METHODS

The expression profile of CENP-H in normal lung epithelial cells, NSCLC cell lines, NSCLC tissues, and adjacent noncancerous lung tissues were detected by reverse transcription-polymerase chain reaction (RT-PCR), real-time RT-PCR, and Western blot analysis. The expression level of CENP-H in 223 NSCLC tissues was measured by immunohistochemistry staining. Statistical analysis was performed to evaluate the clinicopathologic significance of CENP-H.

RESULTS

The expression level of CENP-H was much higher in cancer cell lines and lung cancer tissues than that in normal cells and adjacent noncancerous lung tissues, respectively. Immunohistochemical analysis revealed positive CENP-H expression in 118 of 223 NSCLC tissues (52.9%). Statistical analysis revealed that CENP-H expression was correlated strongly with clinical stage (P=.018), tumor classification (P=.03), and Ki-67 expression (P < .001). Patients with lower CENP-H expression had better overall survival than patients with higher CENP-H expression. Further analysis suggested that CENP-H could predict prognosis only in patients with early-stage disease. Multivariate analysis suggested that CENP-H expression was an independent prognostic marker for survival in patients with NSCLC.

CONCLUSIONS

The current results demonstrated that high CENP-H protein expression was related to poor outcome in patients with NSCLC. CENP-H may be used as a prognostic biomarker for patients lung patients, especially those with early-stage NSCLC.

Sphingosine kinase 1 is associated with gastric cancer progression and poor survival of patients

PURPOSE

The present study was to investigate the clinical significance of sphingosine kinase 1 (SPHK1), an oncoenzyme, in the development and progression of gastric cancer.

EXPERIMENTAL DESIGN

mRNA and protein levels of SPHK1 expression in normal gastric epithelial cells, gastric cancer cell lines, and paired gastric cancer lesions and the adjacent noncancerous tissues were examined using reverse transcription-PCR and Western blotting. Immunohistochemistry was employed to analyze SPHK1 expression in 175 clinicopathologically characterized gastric cancer cases. Statistical analyses were applied to derive prognostic and diagnostic associations.

RESULTS

Levels of SPHK1 mRNA and protein were higher in gastric cancer cell lines than in normal gastric epithelial cells. SPHK1 protein level was up-regulated in gastric cancer lesions compared with that in the paired adjacent noncancerous tissues. Gastric cancer tissues from 115 of 175 (65.7%) patients revealed high level of SPHK1 protein expression in contrast to the undetectable or marginally detectable expression of SPHK1 in the adjacent noncancerous gastric tissues. Significantly different expression levels of SPHK1 were found in patients at different clinical stages (P=0.003), T classification (P=0.035), and M classification (P=0.020). Patients with higher SPHK1 expression had shorter overall survival time, whereas those with lower SPHK1 expression survived longer. Further multivariate analysis suggested that SPHK1 up-regulation was an independent prognostic indicator for the disease.

CONCLUSIONS

SPHK1 protein could be a useful marker for the prognosis of gastric cancer. Further study on the potential use of SPHK1 as a therapeutic target is also warranted.

The presence of Merkel cells and CD10- and CD34-positive stromal cells compared in benign and malignant oral tumors

BACKGROUND

To describe sequential changes in Merkel cells (MC), and CD10(+) and CD34(+) stromal cells (SC) during the transition from benign to malignant oral lesions and correlate with clinicopathologic parameters.

MATERIALS AND METHODS

Changes in cytokeratin 20-positive (CK20(+)) Merkel cells, CD10(+) and CD34(+) SC were immunohistochemically examined in specimens of 28 oral verrucous carcinomas (VC), 32 squamous cell carcinomas (SCC) and 36 benign squamous lesions (BSL). Immunoreactivity and localized inflammation were measured quantitatively and/or semiquantitatively, and between-group results were statistically compared.

RESULTS

The mean number of CD34(+) SC was significantly lower in VC (57.36) and SCC (33.81) than BSL (351.56, P < 0.001). However, the three tumor types had similar staining level and number of CD10(+) SC. We found a significant difference in the density of MC between BSL and VC (P < 0.001) or SCC (P < 0.001). The number of CK20(+) MC was significantly lower in highly inflamed specimens than mildly inflamed specimens (P = 0.001).

CONCLUSION

CD34(+) SC and to a lesser extent MC, but not CD10(+) SC, reveal statistically different density during the transition from benign to malignant oral lesions. The correlations between the CD34(+) SC expression and squamous lesions may be associated with epithelial dysplasia and/or tumor invasion.

Expression of the serine protease, matriptase, in breast ductal carcinoma of Chinese women: correlation with clinicopathological parameters

Matriptase is a serine protease expressed by cells of surface epithelial origin, including epithelial breast tumor cells. Matriptase cleaves and activates proteins implicated in the progression of cancer and represents a potential prognostic and therapeutic target. The aim of this study was to examine matriptase expression in breast tumors of Chinese women and to identify its clinicopathological correlations. Immunohistochemical analysis of matriptase was performed in tissue microarrays of 251 breast tumors including 30 fibroadenomas, 59 ductal carcinomas in situ (DCIS), 38 grade I invasive ductal carcinomas (IDC), 79 grade II IDC, and 45 grade III IDC. The matriptase scores were significantly higher in the tumors than their non-tumor counterparts (178+/-12 for fibroadenoma; 275+/-11 for DCIS; 299+/-10 for grade I IDC; 251+/-10 for grade II IDC; and 314+/-11 for grade III IDC). In cases of IDC, matriptase scores were significantly correlated with tumor staging and nodal staging. Our findings demonstrate that matriptase is over-expressed in breast ductal carcinoma of Chinese women. It therefore may be a good biomarker for diagnosis and treatment of malignant breast tumors.

Solitary fibrous tumors of the pleura: clinical, radiological, surgical and pathological evaluation

AIMS

To report a clinicopathological series of cases of solitary fibrous tumor of the pleura from Taiwan.

METHODS

Clinical data was collected from a review of medical records and telephone interviewing for follow-up.

RESULTS

Eight patients, three men and five women aging from 34 to 71 years, underwent tumor resection and were followed in a period from 7 months to 13.5 years. Six patients underwent standard thoracotomy and two had VATS for tumor excision. Tumors were pathologically benign in seven patients and malignant in one. Patients were all alive with no evidence of tumor recurrence at the time of this report.

CONCLUSIONS

One should always consider SFTPs as potentially malignant tumors. Complete resection remains the mainstay of cure. Standard thoracotomy should always be considered when a high suspicion of malignancy is raised, whereas VATS may be a preferred approach for smaller tumors.

Prolonged survival in a subgroup of patients with brain metastases treated by gamma knife surgery

Object.The authors analyzed the factors involved in determining prolonged survival (≥ 24 months) in patients with brain metastases treated by gamma knife surgery (GKS).

Methods.Between 1995 and 2003, a total of 116 patients underwent 167 GKS procedures for brain metastases. There was no special case selection. Smaller and larger lesions were treated with different protocols. The mean patient age was 56.9 years, the mean number of initial lesions was 3.15, and the mean lesion volume was 10.45 cm.3The mean follow-up time was 9.2 months.

The median patient survival was 8.68 months. One-, 2-, 3-, 4-, and 5-year actuarial survival rates were 31.8%, 19.8%, 14.6%, 7.7%, and 6.9%, respectively. Patient age, number of lesions at presentation, and lesion volume had no influence on patient survival. Twenty-three (19.8%) patients survived for 24 months or more. Certain factors were associated with increased survival time. These were stable primary disease (21 of 23 patients), a long latency between diagnosis of the primary tumor and the occurrence of brain metastases (mean 28.4 months, median 16 months), absence of third-organ involvement, and repeated local procedures. Ten patients underwent repeated GKS (mean 3.4 per patient). Seven patients required open surgery for local treatment failures (recurrence or radiation necrosis). Two patients had both. Fifteen patients underwent repeated procedures.

Conclusions.Aggressive local therapy with GKS, repeated GKS, and GKS plus surgery can achieve increased survival in a subgroup of patients with stable primary disease, no third-organ involvement, and long primary-brain secondary intervals.

Quantitative risk analyses for RCF: survey and synthesis

Refractory ceramic fiber (RCF) is a high-temperature insulating fiber used principally in industrial applications. Epidemiological studies on occupationally exposed cohorts have not indicated that exposure leads to fibrosis, increased lung cancer, or mesothelioma. However, inhalation bioassays with rats and hamsters have shown that these animals can develop each of these endpoints when exposed to high levels of RCF-particle mixtures. This work summarizes relevant quantitative risk analyses based upon analysis of the rat bioassay studies, which lead to predicted unit risks that range nearly three orders of magnitude. Additionally, we identify key assumptions that affect the risk estimates and provide additional estimates using the benchmark dose methodology favored by the U.S. EPA in cases where mechanistic models are inadequate or not available. We show that a key determinant of risk is how lung burdens are normalized (e.g., in terms of the number of fibers per square centimeter of lung surface or the number of fibers per milligram dry lung) for species conversion. Plausible values of unit potency/risk range from 1.4x10(-4) to 7.2x10(-4), neglecting any allowance for the effects of particulate material in the RCF tested in the bioassay experiments.

Dose distribution close to metal implants in Gamma Knife Radiosurgery: a Monte Carlo study

Materials with high atomic numbers favor the occurrence of the photoelectric effect when they are irradiated with gamma rays. Therefore, the photoelectric effects of metal implants within the target regions in Gamma Knife Radiosurgery are worth studying. In the present work, Monte Carlo simulations using EGS4 were employed to investigate the resulting dose enhancements. A dose enhancement as high as 10% was observed close to a platinum implant along the x and y axes, while no significant dose enhancements were observed for silver, stainless steel 301, and titanium ones. A dose enhancement as high as 20% was observed close to the platinum implant along the z axis at the superior position of the metal-phantom interface and was 10% higher for other metal implants.

Choice of phantom materials for dosimetry of Leksell Gamma Knife unit: a Monte Carlo study

In calculations for the Leksell Gamma Knife, GammaPlan employs a tissue equivalent material without the presence of a skull bone, while dosimetry work is based on a polystyrene phantom. The compatibility of these dose distributions is uncertain. The Monte Carlo technique was employed to determine the radial dose distributions from a single 14 mm collimator helmet in 160 mm diam phantoms with different materials. The materials studied were polystyrene, perspex, water, and water with skull bone. Results showed no significant differences among the radial doses in different phantom materials for the 14 mm collimator helmet. The Monte Carlo simulation was repeated with the inclusion of all 201 sources. Again, no significant differences were observed.

Identification of treated target points for parkinsonism on gamma knife follow-up MR images

OBJECT

Identification of treated target points for Parkinsonism on follow-up MR images is difficult because of different orientations employed between the treatment and the follow-up MR scan. In the present work, the treated target points for Parkinsonism can be easily found, once the anterior-commissure (AC) and posterior-commissure (PC) have been defined in Leksell GammaPlan.

METHODS

The follow-up MR images must first be defined with the Cartesian co-ordinate system using a non-fiducial based technique. The mathematics of 3-dimensional coordinate geometry is then applied to locate the treated target points for Parkinsonism. Spreadsheet computer software helped to calculate the exact coordinates of the treated target points quickly and accurately.

CONCLUSIONS

The coordinates of treated target points can be found easily based on the coordinates of the AC and PC points on the follow-up MR images. Different orientations employed between the treatment and the follow-up MR scan are no longer a problem.

SB-242235, a selective inhibitor of p38 mitogen-activated protein kinase. II: in vitro and in vivo metabolism studies and pharmacokinetic extrapolation to man

1. Inhibition of p38 MAP kinase has been investigated extensively as a potential therapy for cytokine-mediated diseases such as autoimmune and inflammatory diseases. SB-242235 (1-(4-piperidinyl)-4-(4-fluorophenyl)-5-(2-methoxy-4-pyrimidinyl) imidazole) is a potent and selective p38 MAP kinase inhibitor; the preclinical pharmacokinetics of SB-242235 have been described previously. The present studies were conducted to describe the in vitro metabolic rates and routes of SB-242235 metabolism, to characterize its in vivo preclinical metabolism, and to use these data to aid in the prediction of the pharmacokinetic behaviour of SB-242235 in man. 2. SB-242235 was metabolically stable in rat, dog, monkey and human hepatic microsomes, isolated hepatocytes and liver slices in vitro. The in vivo preclinical metabolism studies were consistent with the in vitro findings; SB-242235 was minimally metabolized, and was primarily excreted unchanged in the urine (45 and 67% of the administered dose in the rat and monkey, respectively). 3. Allometric scaling using various correction factors predicted that SB-242235 would have low clearance in man with a predicted half-life ranging from 11.5 to 18.7h. This prediction was consistent with the observed mean half-life of 16.4h in the first-in-man study for SB-242235. An allometric scaling method with a correction for interspecies differences in glomerular filtration rate provided the most accurate prediction of the pharmacokinetic behaviour of SB-242235 in humans, although the clinical data also highlight potential difficulties in conducting prospective allometry.

Viral load of high-risk human papillomavirus in cervical squamous intraepithelial lesions

OBJECTIVES

This case-control study was conducted to investigate the role of viral load of high-risk human papillomaviruses (HPVs) in the development of cervical squamous intraepithelial lesions (SILs) and invasive cancers.

METHODS

A total of 30 female cases who had histological evidence of low-grade SIL (n=10) or high-grade SIL and above (n=20) were identified as the case group at the Tri-Service General Hospital, Taipei between September 1998 and March 1999. In addition, 80 female controls who had normal cervical cytology were enrolled and individually matched on age (+/-5 years) and date of recruitment to each case. Cervical swabs collected from study subjects were tested for the positivity and viral load of high-risk HPVs by Hybrid Capture II assay. Additionally, subjects completed a risk factor questionnaire.

RESULTS

Among sex behavioral factors studied, younger age at first intercourse was associated with a significantly elevated risk of cervical SIL and invasive cancers. With respect to HPV infection, high-risk HPV DNA was present in 70% (21/30) of case and 21% (17/80) of control subjects, resulting in an odds ratio (OR) of 6.6 [95% confidence interval (C.I.)=2.6-17.0]. Moreover, women who had a high viral load were at significantly greater risk for cervical SIL and invasive cancers than those who were infected with a low viral load (OR=18.0, 95% C.I.=3.0-108.5).

CONCLUSIONS

Among the variables tested, infection with a high viral load of high-risk HPVs is the strongest determinant for cervical SIL and cervical cancers in Taiwan.

The significance of human papillomavirus viral load in prediction of histologic severity and size of squamous intraepithelial lesions of uterine cervix

OBJECTIVES

Persistence of high-risk types of human papillomavirus (HPV) in cervical scrapes is responsible for the development, maintenance, and progression of squamous intraepithelial lesions (SILs). Previous studies of viral load and histologic severity have ended with controversial results. This study evaluated the relationships of HPV viral load with size and histologic severity of cervical lesions, which has not been reported previously.

METHODS

By using Hybrid Capture II, DNA level of high-risk HPVs was determined in cervical scrapes and correlated with lesion size and histologic confirmation for 73 women referred for colposcopy. The lesion size was classified as nonvisible (n = 12), small (< or =2/5 of the 12x colposcopic visual filed, n = 36), and large (>2/5 of the 12x field, n = 25) lesions. The final disease status was categorized as high-grade SIL (HSIL)/squamous cell carcinoma (SCC) (designated HSIL+) (n = 32), low-grade SIL (LSIL) (n = 19), and no detectable SIL (n = 22).

RESULTS

A distinct upward trend of high-risk HPV DNA levels paralleled increasing size and histologic severity of cervical lesions (P = 0.003 and 0.001, respectively). With respect to relative risk, women who had high viral load of HPV were at significantly greater risk for large lesion size (odds ratio [OR] = 5.3, 95% confidence interval [CI] = 1.1-24.9) and HSIL+ (OR = 35.0, 95% CI = 4.2-294.5). Of particular note, the risk of developing large lesion size and HSIL+ significantly increased with increasing viral load of HPV (P values for trend test were 0.008 and 0.0004, respectively). In contrast, there were no significant associations of trend in viral load with risk in small lesion size and LSIL.

CONCLUSIONS

The present study revealed that the effect of HPV infection on SIL development is highly influenced by high viral load and highlighted a potential application of viral load testing in predicting the size and severity of lesions of the uterine cervix.

Cytokine up-regulation in ischaemic/reperfused lungs perfused with University of Wisconsin solution and normal saline

Ischaemia/reperfusion (I/R) lung injury using University of Wisconsin solution (UW) as perfusate has not been well studied. Isolated rat lungs were challenged with various periods of ischaemia and/or reperfusion. Haemodynamics, lung weight gain (LWG), capillary filtration coefficient (K(fc)), tissue pathology, the concentrations of cytokines in the perfusate, and mRNAs for the various cytokines in the lung tissues were measured. I/R induced a permeability type of pulmonary oedema, as reflected by increases in LWG and K(fc). LWG and K(fc) in the I(45)R(60)(UW) group (45 min of ischaemia followed by 60 min of reperfusion with UW) were only 2% and 5% respectively of those in the I(45)R(60)(NS) group (where NS is normal saline). LWG and K(fc) in the UW group had both increased by 180 min, to values similar to those in the I(45)R(60)(NS) group. However, these findings show that UW was remarkably effective at preventing LWG after 60 min of reperfusion, and was more than 3-fold more effective than NS in delaying LWG. For longer ischaemic times only, or the same period of ischaemia followed by longer reperfusion periods, greater lung injury occurred. I/R lung injury also induced increased concentrations of tumour necrosis factor-alpha (TNF-alpha), interleukin 1 and interleukin 6 in the perfusate, and increased the mRNAs for these cytokines in lung tissue. A significant correlation was obtained between TNF-alpha concentration and LWG. TNF-alpha production in the I(45)R(60)(UW) group was only 7% of that in the I(45)R(60)(NS) group. However, TNF-alpha mRNA expression in the I(45)R(60)(UW) group was 80% of that in the I(45)R(60)(NS) group. This indicates that transcription/translation do not correlate well with cytokine production, and also suggests that one reason for the effectiveness of UW in delaying LWG may be because it delays TNF-alpha production. In summary, ischaemia or I/R caused a permeability-type pulmonary oedema that was associated with leucocyte infiltration and the up-regulation of various cytokines, regardless of the perfusion fluid. Except for pulmonary hypertension, less severe I/R lung injury and delayed cytokine production in lungs perfused with UW, the pattern of injury associated with I/R challenge was similar to that in lungs perfused with NS. We propose that more or long-acting protective agents are required as additives in order to modify UW to produce an optimal preservation solution.

Evaluation of the Human Nickel Retention Model with Workplace Data

A previously developed dosimetry model of inhaled Ni compounds in the human lung has been expanded by incorporating three additional factors: (1) inhalability, (2) mixed breathing mode, and (3) clearance rate coefficient of a Ni compounds' mixture. Predicted lung burdens of Ni compounds from the expanded model for workers at different departments in a Ni refinery plant compared favorably with the reported data. Although many uncertainties remain, the present model represents a first step toward developing a more meaningful risk assessment tool that will allow for more accurate extrapolation of animal data to humans.

Diffuse leiomyomatosis of the esophagus

BACKGROUND

Leiomyomas are rare esophagus neoplasms. They are usually solitary, and the diffuse lesion is extremely rare.

CASE REPORT

A 19-year-old male presented with a 3-year history of occasional dysphagia and postprandial regurgitation. The chest radiographs showed a huge mass in the posterior mediastinum. Barium esophagograms showed narrowing of the middle third esophagus with proximal dilatation. The fibroesophagoscopy demonstrated multiple submucosal nodules below a level 22 cm from the incisor and covered with intact mucosa. CT scans of the chest showed a long segment of circumferential soft tissue in the posterior mediastinum which encircled and involved the upper two thirds of the esophagus. An intrathoracic esophagectomy with cervical esophagogastrostomy via the substernal route was performed. Grossly, multiple confluent myomatous nodules circumferentially involved the upper and middle third of the esophagus. Histologic findings showed diffuse leiomyomatosis of the esophagus.

CONCLUSION

Esophageal leiomyomatosis should be considered in a young patient with long-standing dysphagia in whom smooth, tapered esophageal narrowing on barium study and circumferential esophageal wall thickening on CT scan are seen. An esophagectomy combined with a reconstruction procedure is indicated.

Dose distributions at extreme irradiation depths of gamma knife radiosurgery: EGS4 Monte Carlo calculations

The accuracy of the dose planning system (Leksell GammaPlan), used in Gamma Knife (type B) radiosurgery at extreme irradiation depths, was verified using the Monte Carlo technique. EGS4 Monte Carlo calculations were employed to calculate the dose distribution along the x, y and z axes for an irradiation relatively shallow in a spherical bony cavity water phantom. Two different sizes of the collimator helmets, 8 and 18 mm, of the Leksell Gamma Knife Unit were studied. The results of GammaPlan showed good consistency with the Monte Carlo results. Furthermore, small dose enhancements were observed in the skull bone where accurate dose measurements are difficult due to the presence of the air-phantom interface. Therefore, the results of this project can promote confidence to all Gamma Knife centres in the world when using the Leksell GammaPlan.

A retrospective review of the carcinogenicity of refractory ceramic fiber in two chronic fischer 344 rat inhalation studies: an assessment of the MTD and implications for risk assessment

The purpose of this article is to review previous chronic inhalation studies in rats with refractory ceramic fiber (RCF), the mathematical modeling efforts to describe the deposition, clearance, and retention of RCF fiber in the rat and human, and the concept of "overload," and to assess the possibility that the maximum tolerated dose (MTD) was exceeded. Lastly, based on recent biopersistence and pulmonary clearance studies of several investigators with a particulate-free RCF, we examine the potential impact on the chronic RCF rat bioassay of coexposure to both RCF particulate and RCF fibers. The review concludes, inter alia, that RCF particulate coexposure probably had a major impact on the observed chronic adverse effects, that the MTD was probably exceeded at the highest exposure concentration of 30 mg/m(3) in the rat bioassay, and that inclusion of the highest dose in the risk assessment process may overstate human health risk if a linear rather than nonlinear model is used.

Lymphoma of bone with initial presentation as a calvarial mass

A 21-year-old man was examined for a right frontal skull mass that had been present for 4 months. Excision biopsy of the mass revealed diffuse large B-cell lymphoma. Subsequent studies showed right preauricular lymphadenopathy but no systemic involvement. The patient was treated with six courses of CHOP (cyclophosphamide, adriamycin, vincristine, and prednisolone) with adjuvant whole brain irradiation and achieved a complete remission.

Dexamethasone and pentastarch produce additive attenuation of ischaemia/reperfusion lung injury

The choice of an intravenous solution for the attenuation of ischaemia/reperfusion (I/R) lung injury is still a difficult one. Although 10% (w/v) pentastarch has been used in ICU settings, its use in I/R lung injury has not been well explored. We hypothesized that this synthetic colloid substance, which maintains colloid osmotic pressure and potentially 'seals' capillary leaks, in combination with an anti-inflammatory agent (i.e. dexamethasone), would ameliorate I/R lung injury. After 60 min of lung ischaemia in an isolated rat lung model, lungs were reperfused for 60 min in a closed circulating system with one of the following solutions: (1) NS (0.9% normal saline), (2) NS+Dex (dexamethasone), (3) NS+Penta (pentastarch), or (4) NS+Penta+Dex. Haemodynamic changes, lung weight gain (LWG), capillary filtration coefficient (K(fc)) and lung pathology were analysed. Results showed significantly lower values of K(fc) and LWG in pentastarch- or dexamethasone-perfused groups as compared with those in the NS group. Dexamethasone as an additive to NS+Penta further decreased K(fc) and LWG. Histopathological studies showed similar decreases in injury profiles. We conclude that reperfusion with dexamethasone and pentastarch can attenuate I/R lung injury, and that dexamethasone and pentastarch have additive effects. Our data thus suggest that the combination of a colloid substance with 'sealing effects' and an anti-inflammatory agent may provide a better reperfusion solution for patients with I/R lung injury or for lungs stored for transplant.