EPO promotes the progression of rheumatoid arthritis by inducing desialylation via increasing the expression of neuraminidase 3

OBJECTIVE

Erythropoietin (EPO) known as an erythrocyte-stimulating factor is increased in patients with rheumatoid arthritis (RA). Nevertheless, the function of EPO in the process of RA and relative mechanism needs to be further clarified.

METHODS

The level of EPO in serum and synovial fluid from patients with RA and healthy controls was determined by . Collagen-induced arthritis (CIA) mice were constructed to confirm the role of EPO on RA pathogenesis. Differentially expressed genes (DEGs) of EPO-treated fibroblast-like synoviocyte (FLS) were screened by transcriptome sequencing. The transcription factor of neuraminidase 3 (NEU3) of DEGs was verified by double luciferase reporting experiment, DNA pulldown, electrophoretic mobility shift assay and chromatin immunoprecipitation-quantitative PCR (qPCR) assay.

RESULTS

The overexpression of EPO was confirmed in patients with RA, which was positively associated with Disease Activity Score 28-joint count. Additionally, EPO intervention could significantly aggravate the joint destruction in CIA models. The upregulation of NEU3 was screened and verified by transcriptome sequencing and qPCR in EPO-treated FLS, and signal transducer and activator of transcription 5 was screened and verified to be the specific transcription factor of NEU3. EPO upregulates NEU3 expression via activating the Janus kinase 2 (JAK2)-STAT5 signalling pathway through its receptor EPOR, thereby to promote the desialylation through enhancing the migration and invasion ability of FLS, which is verified by JAK2 inhibitor and NEU3 inhibitor.

CONCLUSION

EPO, as a proinflammatory factor, accelerates the process of RA through transcriptional upregulation of the expression of NEU3 by JAK2/STAT5 pathway.

CCCTC-binding factor: the specific transcription factor of β-galactoside α-2,6-sialyltransferase 1 that upregulates the sialylation of anti-citrullinated protein antibodies in rheumatoid arthritis

OBJECTIVE

Sialylation of the crystallizable fragment (Fc) of ACPAs, which is catalysed by β-galactoside α-2,6-sialyltransferase 1 (ST6GAL1) could attenuate inflammation of RA. In this study, we screened the transcription factor of ST6GAL1 and elucidated the mechanism of transcriptionally upregulating sialylation of ACPAs in B cells to explore its role in the progression of RA.

METHODS

Transcription factors interacting with the P2 promoter of ST6GAL1 were screened by DNA pull-down and liquid chromatography with tandem mass spectrometry (LC-MS/MS), and verified by chromatin immunoprecipitation (ChIP), dual luciferase reporter assay and electrophoretic mobility shift assay (EMSA). The function of the CCCTC-binding factor (CTCF) on the expression of ST6GAL1 and the inflammatory effect of ACPAs were verified by knocking down and overexpressing CTCF in B cells. The CIA model was constructed from B cell-specific CTCF knockout mice to explore the effect of CTCF on arthritis progression.

RESULTS

We observed that the levels of ST6GAL1 and ACPAs sialylation decreased in the serum of RA patients and were negatively correlated with DAS28 scores. Subsequently, CTCF was screened and verified as the transcription factor interacting with the P2 promoter of ST6GAL1, which enhances the sialylation of ACPAs, thus weakening the inflammatory activity of ACPAs. Furthermore, the above results were also verified in the CIA model constructed from B cell-specific CTCF knockout mice.

CONCLUSION

CCCTC-binding factor is the specific transcription factor of β-galactoside α-2,6-sialyltransferase 1 in B cells that upregulates the sialylation of ACPAs in RA and attenuates the disease progression.

[Analysis of respiratory syncytial virus nonstructural protein 1 amino acid variation and clinical characteristics]

Objective: To investigate the relationship between amino acid variations of respiratory syncytial virus (RSV) nonstructural protein (NS) 1 and the clinical characteristics. Method: A retrospective case review was conducted. From December 2018 to January 2020, a total of 81 cases of hospitalized children who were tested only positive for RSV by RT-PCR or PCR at the Department of Respiratory Medicine, Children's Hospital of Chongqing Medical University were included in the study. The NS1 genes of RSV subtype A and subtype B were amplified by PCR and sequenced. The amino acid sequences were analyzed. The Chi-square test and Mann-Whitney rank sum test were used to compare the clinical characteristics and type Ⅰ interferon levels of children with or without NS1 variation in the variation and non-variation groups. Results: Among 81 cases, there were 58 males and 23 females. There were 11 cases in the variation group, the age of onset was 2.0 (1.0, 11.0) months, included 4 cases of subtype A (variant sites were: 2 cases for Lys33Gln, one case for Gly2Asp, Pro67Ser, Leu137Phe, respectively) and 7 cases of subtype B (variant sites were: two cases for Val121Ile, one case for Tyr30Cys, Val65Met, Asn85Ser, Ser118Asn, Asp124Asn, respectively). These variant sites all appeared at a very low frequency 0.08 (0.04, 0.29) % in the NCBI PROTEIN database. There were 70 cases in non-variation group, the onset age was 3.5 (1.0, 7.0) months. The proportion of dyspnea in the variation group was higher than that in the non-variation group (10/11 vs. 47% (33/70), χ²=7.31, P<0.01). Conclusions: There are some variant sites in nonstructural protein NS1 of RSV. Children may be prone to have dyspnea with NS1 variations.

[Metagenomic sequencing for diagnosis of sparganosis mansoni: a case report]

The patient was found to develop a migrating mass in the lower abdomen without any known cause in 2000, and the cause had not been identified following multiple diagnoses since then. The mass was found to migrate to the left anterior axillary regions on August 11, 2020. Then, three segments of incomplete white worms were resected through minimally invasive surgery, and metagenomic sequencing revealed sparganosis mansoni. After surgical resection of complete worms was performed on October 21, 2021, the case was cured and discharged from the hospital. Follow-up revealed satisfactory outcomes and no new mass was found throughout the body.

Connective tissue growth factor-targeting DNA aptamer suppresses pannus formation as diagnostics and therapeutics for rheumatoid arthritis

Connective tissue growth factor (CTGF) has been recently acknowledged as an ideal biomarker in the early disease course, participating in the pathogenesis of pannus formation in rheumatoid arthritis (RA). However, existing approaches for the detection of or antagonist targeting CTGF are either lacking or unsatisfactory in the diagnosis and treatment of RA. To address this, we synthesized and screened high-affinity single-stranded DNA aptamers targeting CTGF through a protein-based SELEX procedure. The structurally optimized variant AptW2-1-39-PEG was characterized thoroughly for its high-affinity (KD 7.86 nM), sensitivity (minimum protein binding concentration, 2 ng), specificity (negative binding to other biomarkers of RA), and stability (viability-maintaining duration in human serum, 48 h) properties using various biochemical and biophysical assays. Importantly, we showed the antiproliferative and antiangiogenic activities of the aptamers obtained using functional experiments and further verified the therapeutic effect of the aptamers on joint injury and inflammatory response in collagen-induced arthritis (CIA) mice, thus advancing this study into actual therapeutic application. Furthermore, we revealed that the binding within AptW2-1-39-PEG/CTGF was mediated by the thrombospondin 1 (TSP1) domain of CTGF using robust bioinformatics tools together with immunofluorescence. In conclusion, our results revealed a novel aptamer that holds promise as an additive or alternative approach for CTGF-targeting diagnostics and therapeutics for RA.

Hsa_circ_0011946 promotes the migration and invasion of hepatocellular carcinoma by inducing EMT process

OBJECTIVE

Recently, the vital role of circular RNAs is discovered in many diseases including tumor progression and metastasis. Hepatocellular carcinoma (HCC) is one of the most ordinary malignant tumors. The purpose of our study is to detect the potential function of hsa_circ_0011946 in HCC to offer new biomarkers and targets.

PATIENTS AND METHODS

The level of hsa_circ_0011946 in HCC tissues and cell lines was monitored by Real Time Quantitative Polymerase Chain Reaction (RT-qPCR). Pearson's Chi-square test was used to determine the association between hsa_circ_0011946 expression and several clinicopathological factors. Then, hsa_circ_0011946 was knocked down in HCC cells to uncover its function in metastasis of HCC. Cell migrated and invaded ability was measured through transwell assay, Matrigel assay and wound healing assay. Western blot assay was performed to analyze the effect of hsa_circ_0011946 on the epithelial-to-mesenchymal transition (EMT) process.

RESULTS

In this research, the expression level of hsa_circ_0011946 was significantly increased in HCC tissues compared to that in adjacent samples. The expression of hsa_circ_0011946 was also increased in HCC cell lines. The hsa_circ_0011946 expression was associated with lymphatic metastasis in HCC patients. Knockdown of hsa_circ_0011946 led to the inhibition of cell migration and invasion in HCC. In addition, results of further experiments revealed that the EMT-related proteins were regulated via the knockdown of hsa_circ_0011946 in HCC.

CONCLUSIONS

The hsa_circ_0011946 could enhance cell migration and invasion of HCC by inducing the EMT process.

Is lower low-density lipoprotein cholesterol associated with lower androgen and erectile dysfunction in men?

BACKGROUND AND AIMS

Therapeutic possibilities now exist to lower low-density lipoprotein cholesterol (LDL-C) to very low levels. However, substantial controversy remains in clinical practice with regard to its safety, and the question of whether low LDL-C levels per se may provoke adverse effects in humans arises. We aimed to explore the association of LDL-C with androgen and erectile dysfunction (ED) in a general population of men.

METHODS AND RESULTS

A total of 4203 men without hormone replacement therapy were enrolled from 22 sites in East China. Total testosterone (T) and Free T were assessed. Free androgen index (FAI) was calculated. The IIEF-5 questionnaire was used to assess ED. We found that free T and FAI gradually and markedly increased with increasing LDL-C levels. Using linear regression, after adjusting for age, educational level, economic status, smoking status, drinking status, BMI, diabetes, and use of lipid-lowering medication, LDL-C was positively associated with free T (B = 0.175, 95% CI: 0.084, 0.266) and FAI (B = 0.064, 95% CI: 0.016, 0.112). Meanwhile, there was a U-shaped curvilinear relationship between LDL-C and prevalence of ED. In the logistic regression analysis, compared to those with LDL-C among the 10th-90th percentile, the ORs of ED in men in the lowest and highest deciles were 1.938 (95% CI: 1.121, 3.349) and 1.804 (95% CI: 1.117, 2.916), respectively.

CONCLUSION

Lower LDL-C levels were significantly associated with lower free T and lower FAI in a general population of men. Moreover, both low and high levels of LDL-C might be risk factors for ED.

Abstract P1-03-10: HER2 expression in clinical breast cancer samples: A novel detection methodology for HER2 protein quantitation using fluorescent nanoparticles

Background: The human epidermal growth factor receptor-2 (HER2) is a member of a family of transmembrane tyrosine kinase receptors that play an important role in regulated normal cell growth and differentiation. The over-expression of HER2 in a subset of 15-20% of invasive breast cancers has an important bearing on prognosis, as HER2-positive tumors are associated with an aggressive clinical course and poor outcome. Targeting HER2-overexpression has been shown to be a remarkably effective therapeutic modality; however testing of tumor samples to assess the HER2 status of the patient's breast cancer is required. Clinical assays to assess the HER2 status in patients being considered for targeted therapy include immunohistochemistry (IHC), which detects protein over-expression, or fluorescence in situ hybridization (FISH), which detects gene amplification. Both the IHC and FISH methodologies have limitations. Given that the target of the currently approved drugs is the receptor protein, novel detections systems that could more accurately and quantitatively detect HER2 protein in clinical samples over a broad dynamic range would be advantageous and may be clinically helpful.

Material and Methods: A novel detection technology using streptavidin-coated Phosphor Integrated Dot fluorescent nanoparticles (PID) has been developed that can be visualized by fluorescence microscopy and used for quantitative immunofluorescence detection of protein in clinical samples using computer assisted image analysis. In the current study, PID- nanoparticles were used to analyze HER2 protein expression in breast cancer cell lines and 120 well characterized breast cancer samples. These results have been compared with HER2 IHC and HER2 FISH analysis.

Results: The expression levels of HER2 protein from 8 breast cancer cell lines was evaluated by antibody-binding capacity with FACS analysis. Formalin fixed paraffin embedded cell pellets for these cell lines were prepared and used for quantitative HER2 analysis by PID. The PID score/cell for each of these cell lines showed a strong linear correlation with antibody-binding capacity sites/cell by FACS analysis (R2 = 0.94). For the 120 breast cancer samples, PID score/cell was measured and compared against HER2 IHC membrane intensity measure by image analysis (Aperio) and HER2 FISH results. The HER2 PID score/cell showed a correlation coefficient of R2=0.72 versus the average HER2 copy number per cell by FISH, compared with a correlation coefficient of R2=0.41 for HER2 IHC membrane intensity measured by Aperio. For the HER2/CEP17 ratio, the correlation coefficient for the PID score/cell was R2=0.79 compared with a correlation coefficient of R2=0.32 for the HER2 IHC membrane intensity.

Conclusions: PID-nanoparticles demonstrate great potential for the quantitative measurement of protein of clinical interest in routine clinical samples with morphologic confirmation of the tissue being studied. Further studies looking for PID-score thresholds for HER2 gene amplification and correlations with clinical outcome data are warranted and ongoing.

Citation Format: Hicks DG, Goda H, Zhai H, Okada H, McMahon L, Sullivan N, Tang P, Nakano Y. HER2 expression in clinical breast cancer samples: A novel detection methodology for HER2 protein quantitation using fluorescent nanoparticles [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-03-10.

True digestible phosphorus requirement for forty- to eighty-kilogram pigs

The objective of this study was to determine the true digestible P requirement of 40- to 60-kg (Exp. 1) and 60- to 80-kg (Exp. 2) pigs by broken-line analysis of growth performance data using 6 levels of true digestible P. In each 3-wk experiment, 108 barrows and gilts were used, and 6 levels of monocalcium phosphate were added to a corn-soybean meal-based diet to establish 6 graded levels of true total tract digestible P ranging from 1.26 to 3.98 g/kg of diet in Exp. 1 or from 1.21 to 3.31 g/kg in Exp. 2. The true digestible P content was calculated using true total tract digestibility of 40.53%, 35.96%, and 84.31% for P in corn, soybean meal, and monocalcium phosphate, respectively. Limestone was added accordingly to maintain a constant Ca level across all diets of each experiment. The results of Exp. 1 showed that with graded supplementation of monocalcium phosphate, ADG linearly increased ( < 0.001) in wk 1 and both linearly and quadratically increased ( < 0.01) in wk 2, wk 3, and wk 0 to 3, and G:F linearly improved ( < 0.001) in wk 1, quadratically improved ( < 0.05) in wk 3, and both linearly and quadratically improved ( < 0.05) in wk 2 and wk 0 to 3 ( < 0.05). In Exp. 2, ADG linearly increased ( < 0.001) in wk 1 and both linearly and quadratically increased ( < 0.05) in wk 2, wk 3, and wk 0 to 3, with the graded supplementation of monocalcium phosphate, and G:F linearly improved ( < 0.01) in wk 1 and wk 3 and both linearly and quadratically improved ( < 0.001) in wk 2 and wk 0 to 3. In Exp. 1, the true digestible P requirement was estimated to be 2.66, 2.79, and 2.51 g/kg of diet (884 g DM/kg) for pigs of mixed sex, barrows, and gilts, respectively, on the basis of broken-line regression of ADG data for wk 0 to 3 against 6 true digestible P levels. Using G:F, the P requirement estimate was correspondingly 2.67, 2.51, and 2.93 g/kg of diet. In Exp. 2, the true digestible P requirement was estimated to be 2.29, 2.20, and 2.39 g/kg of diet (884 g DM/kg) using ADG data for wk 0 to 3 as the response variable and to be 2.33, 2.19, and 2.47 g/kg using wk 0 to 3 G:F data for pigs of mixed sex, barrows, and gilts, respectively. In conclusion, the mean TTTD-based P requirement was 2.66 and 2.31 g/kg of diet (884 g DM/kg) for 40- to 60-kg and 60- to 80-kg pigs, respectively.

Development of secondary mutations in wild-type and mutant EZH2 alleles cooperates to confer resistance to EZH2 inhibitors

The histone methyltransferase Enhancer of Zeste Homolog 2 (EZH2) is frequently dysregulated in cancers, and gain-of-function (GOF) EZH2 mutations have been identified in non-Hodgkin lymphomas. Small-molecule inhibitors against EZH2 demonstrated anti-tumor activity in EZH2-mutated lymphomas and entered clinical trials. Here, we developed models of acquired resistance to EZH2 inhibitor EI1 with EZH2-mutated lymphoma cells. Resistance was generated by secondary mutations in both wild-type (WT) and GOF Y641N EZH2 alleles. These EZH2 mutants retained the substrate specificity of their predecessor complexes but became refractory to biochemical inhibition by EZH2 inhibitors. Resistant cells were able to maintain a high level of H3K27Me3 in the presence of inhibitors. Interestingly, mutation of EZH2 WT alone generated an intermediate resistance phenotype, which is consistent with a previously proposed model of cooperation between EZH2 WT and Y641N mutants to promote tumorigenesis. In addition, the findings presented here have implications for the clinical translation of EZH2 inhibitors and underscore the need to develop novel EZH2 inhibitors to target potential resistance emerging in clinical settings.

Gastroretentive extended-release floating granules prepared using a novel fluidized hot melt granulation (FHMG) technique

The objective of this work was to investigate the feasibility of using a novel granulation technique, namely, fluidized hot melt granulation (FHMG), to prepare gastroretentive extended-release floating granules. In this study we have utilized FHMG, a solvent free process in which granulation is achieved with the aid of low melting point materials, using Compritol 888 ATO and Gelucire 50/13 as meltable binders, in place of conventional liquid binders. The physicochemical properties, morphology, floating properties, and drug release of the manufactured granules were investigated. Granules prepared by this method were spherical in shape and showed good flowability. The floating granules exhibited sustained release exceeding 10 h. Granule buoyancy (floating time and strength) and drug release properties were significantly influenced by formulation variables such as excipient type and concentration, and the physical characteristics (particle size, hydrophilicity) of the excipients. Drug release rate was increased by increasing the concentration of hydroxypropyl cellulose (HPC) and Gelucire 50/13, or by decreasing the particle size of HPC. Floating strength was improved through the incorporation of sodium bicarbonate and citric acid. Furthermore, floating strength was influenced by the concentration of HPC within the formulation. Granules prepared in this way show good physical characteristics, floating ability, and drug release properties when placed in simulated gastric fluid. Moreover, the drug release and floating properties can be controlled by modification of the ratio or physical characteristics of the excipients used in the formulation.

First Report of Fusarium equiseti Causing a Sheath Rot of Corn in China

Corn is the most important cereal crop in China. Over 34.94 million ha of corn is cultivated in the country annually. However, fungal diseases are a major limiting factor in corn production. In August 2008, 50 ha in several corn fields in Liaoning, Jilin, and Heilongjiang provinces were observed to be severely affected by a disease causing a yield loss of 30%. Results from field surveys suggested an epidemic during late corn growth stages that affected corn sheaths, causing irregularly circular spots with grayish brown to dark brown lesions. Lesions ranged from 2.5 to 3 × 3 to 5 cm. To isolate the causal agent, tissue was removed from the border of lesions and surface sterilized in 75% ethanol for 30 sec and 0.1% HgCl₂ for 1 min. The sample was then triple rinsed in sterile distilled water. The isolate was purified and subcultured on potato dextrose agar (PDA) at 25 ± 2°C. The initial color of the mycelium was white, turning brown after being cultured for 7 days. A pale brown to dark brown pigment developed in the agar beneath the colony. Chlamydospores, solitary but also in short chains, measuring 7.2 to 15.3 μm, were produced on carnation leaf agar (CLA) after 10 days and became verrucose 20 days later. Macroconidia were produced on CLA in orange sporodochia from monophialides on branched conidiophores, usually 5- to 7-septate, and apical cells were tapered and elongate. Basal cells were prominent, foot-shaped, and elongated in appearance. Microconidia were not observed (1). These morphological characteristics matched the description of Fusarium equiseti reported by Leslie and Summerell (1). A pathogenicity test was conducted with an isolate from each of the 36 corn plants by spraying 2 ml of spore suspension (10⁶ conidia/ml) on 45-day-old corn sheaths (cv. Huang Zao). For the control treatment, 36 corn plants were sprayed with an equal volume of sterilized water. Inoculated plants were placed in a greenhouse at 32 to 34°C and 95% relative humidity. Typical irregularly circular lesions were observed 7 days after inoculation, except in the control samples. Each treatment was replicated three times. The suspected pathogen was consistently re-isolated from diseased tissue according to Koch's postulates, and was found to be morphologically similar to F. equiseti. Preliminary morphological identification of the fungus was confirmed by a PCR assay using genomic DNA extracted from the mycelia of a 7-day-old culture on PDA at 25 ± 2°C. A 750-bp amplified region of the transcription elongation factor (TEF) of rDNA was generated using TEF1 (5'-ATGGGTAAGGAGGACAAGAC-3') and TEF2 (5'-GGAAGTACCAGTGATCATGTT-3') primers. The TEF region (GenBank Accession No. KF754798) was sequenced by Sangon Biotech Co., Ltd. (Shanghai, China) and displayed 99% nucleotide similarity with the rDNA-TEF of F. equiseti (JN127347.1) separately after a BLASTn search in GenBank. Based on the symptoms, fungal morphology, TEF sequence, and pathogenicity testing, this fungus was identified as F. equiseti. To our knowledge, this is the first report of F. equiseti on corn sheaths in China. This report will establish a foundation for further study of F. equiseti to address the disease effectively and to determine the severity of damage caused by F. equiseti. Reference: (1) J. F. Leslie and B. A. Summerell. The Fusarium Laboratory Manual. Blackwell, Ames, IA, 2006.

True digestible phosphorus requirement for twenty- to forty-kilogram pigs

The objective of this study was to determine the true digestible P requirements of 20- to 40-kg pigs by the broken-line regression analysis of growth performance using 6 levels of true total-tract digestible P. In Exp. 1, 24 barrows (initial BW=25.2±1.0 kg) were used to determine the true total-tract digestibility (TTTD) of P in monocalcium phosphate using the regression method. The dietary treatments included a corn-soybean meal-based diet (2.96 g total P/kg) and 3 additional dietary treatments with incremental addition of 0.50 g P/kg through monocalcium phosphate. Limestone (37.2% Ca) was added to maintain a constant Ca to P ratio of 1.25 to 1 across all diets. A 5-d adjustment period preceded a 5-d total collection of feces. Ferric oxide was used as a marker to time the initiation and termination of fecal collection. In Exp. 2, 108 barrows and gilts (initial BW=20.1±1.2 kg) were used in a 3-wk growth performance trial. Monocalcium phosphate was added to a corn-soybean meal-based diet to set up 6 levels of TTTD-based digestible P, ranging from 1.31 to 4.64 g/kg of diet with increments of 0.67 g/kg digestible P. Limestone was added to maintain a constant Ca level across all diets. The results of Exp.1 showed that dietary P intake, fecal P output, digested P, and apparent total-tract digestibility of P increased linearly (P<0.05) with the increasing supplementation of monocalcium phosphate. Regressing daily digested P against daily P intake resulted in TTTD of 84.3% for P in monocalcium phosphate. In Exp. 2, ADG, ADFI, and G:F increased both linearly (P<0.01) and quadratically (P<0.05) with increasing P level in wk 1 and 3 and for the overall 3-wk duration. In wk 2, both linear and quadratic effects of P level were observed for ADG and ADFI (P<0.05) whereas the G:F only showed linear improvement (P<0.01). The true digestible P requirement, defined as the breakpoint using the overall 3-wk G:F as the response variable, was estimated to be 3.03, 2.98, and 3.08 g/kg of diet for pigs of mixed sex, barrows, and gilts, respectively. Using ADG, the corresponding estimates of P requirement were 3.09, 3.08, and 3.10 g/kg of diet. In conclusion, the mean true digestible P requirement of pigs from 20 to 40 kg BW was determined to be 3.06 g/kg of diet using the average of the estimates for barrows and gilts based on ADG.

True digestible phosphorus requirement of 10- to 20-kg pigs

The objective of this study was to determine the true digestible P requirement of 10- to 20-kg pigs by broken-line regression analysis of growth performance using 6 levels of true total-tract digestible P. In Exp. 1, 48 barrows were used to determine the true total-tract digestibility (TTTD) of P in monocalcium phosphate using the regression method. The dietary treatments included a negative control (3.30 g/kg total P) and 7 additional dietary treatments with incremental addition of 0.74 g/kg P through monocalcium phosphate, resulting in a dietary range of 3.30 to 8.45 g/kg total P. Limestone was added accordingly to maintain a constant Ca to P ratio of 1.25:1 across all diets. A 5-d adjustment period preceded a 5-d total collection of feces. Ferric oxide was used to time the initiation and termination of fecal collection. In Exp. 2, 108 barrows and gilts were used in a 3-wk growth performance study. Monocalcium phosphate was added to a corn-soybean meal-based diet to set up 6 levels of TTTD-based digestible P, ranging from 1.55 to 4.21 g/kg at an increment of 0.53 g/kg digestible P. Limestone was added accordingly to maintain a constant Ca level across all diets. The results of Exp.1 showed dietary P intake, fecal P output, and digested P increased linearly (P < 0.001) with the increasing P level, whereas the apparent total-tract digestibility of P increased both linearly and quadratically (P < 0.01). The regression of daily digested P against daily P intake gave a TTTD of 67.5% for P in monocalcium phosphate. In Exp. 2, ADG increased linearly (P < 0.001) with the increasing P level in wk 1. In wk 2, wk 3, and the overall 3-wk duration, both linear and quadratic effects of P level (P < 0.05) were observed for ADG. Average daily feed intake increased with the addition of monocalcium phosphate linearly in wk 2 (P < 0.05) and during the overall period (P < 0.001) and both linearly (P < 0.001) and quadratically (P < 0.05) in wk 3. For any period, the G:F was improved in both a linear (P < 0.001) and quadratic (P < 0.05) fashion. The true digestible P requirement, defined as the breakpoint using G:F of the overall duration, was estimated to be 3.22, 2.81, and 3.45 g/kg of diet with dietary DM averaged at 887 g/kg for pigs of mixed sex, barrows, and gilts, respectively. Using ADG, the corresponding P requirement was 3.19, 3.40, and 2.97 g/kg of diet. In conclusion, the true digestible P requirement of pigs from 10 to 20 kg BW was determined to be 3.2 g/kg of diet.

True total-tract digestibility of phosphorus in corn and soybean meal for fifteen-kilogram pigs are additive in corn-soybean meal diet

The objective of this study was to verify the additivity of true total-tract P digestibility (TPD) in corn and soybean meal (SBM) for 15-kg pigs. Fifty-four barrows with an average initial BW of 14.7±1.6 kg were used in a randomized complete block design with a 3×2 factorial arrangement of 6 diets. Three P sources included corn, SBM, and their mixture at a ratio of 2:1. Each P source was provided at low or high level. The diets were fed for a 5-d adjustment period followed by a total collection period of 7 d with ferric oxide as a marker to determine the initiation and termination of fecal collection. The results showed the high P level of each P source increased (P<0.001) P intake, fecal P output, and digested P compared with the low P level. The respective apparent total-tract digestibility of P were 35.66 and 40.57% for low and high P levels in corn, 35.72 and 38.04% for low and high P levels in SBM, and 41.85 and 38.53% for low and high P levels in the corn-soybean meal mixture without significant difference between P levels within P sources. Regressing daily digested P against daily P intake, the TPD was estimated at 40.53, 35.96, and 37.52% for corn, SBM, and their mixture, respectively. The expected TPD in corn and SBM mixture was calculated to be 37.92% based upon the P contribution coefficient calculated to be 0.428 for corn and 0.572 for SBM. The determined TPD (37.52%) in the mixture was not statistically different from the expected (37.92%). In conclusion, the TPD in corn and SBM are additive in corn-soybean meal diet for pigs.

Apparent and standardized ileal digestibilities of amino acids for pigs fed corn- and soybean meal-based diets at varying crude protein levels

The objective of this study was to determine the effect of CP level in corn- and soybean meal-based diets on apparent (AID) and standardized ileal digestibility (SID) of AA. Six pigs (initial BW, 47.1 ± 1.0 kg) fitted with T-cannula at the distal ileum were fed 6 diets for 6 periods in a 6 × 6 Latin square design. The 6 diets consisted of a nitrogen-free diet and 5 corn- and soybean meal-based diets that contained CP of 68, 105, 141, 177, and 214 g/kg. Each period consisted of a 5-d adjustment period and 2 d of ileal digesta collection for 10 h on each of d 6 and 7. The ratio of corn:soybean meal was fixed at 3 to 2 by weight and cornstarch was added to dilute the CP concentration. Chromic oxide was added at 5 g/kg as an indigestible marker. The results showed basal endogenous loss ranged from 65 mg/kg of DMI for Met to 3,104 mg/kg of DMI for Pro. Proline and Gly (1,053 mg/kg of DMI) were the 2 most abundant AA in endogenous flow and together accounted for approximately 43% of the total endogenous AA flow. Of the basal ileal endogenous CP, total AA accounted for 82%. The AID were 80.9 to 84.7%, 85.1 to 87.4%, 72.9 to 79.5%, and 86.5 to 87.9% for Lys, Met, Thr, and Trp, respectively, with corresponding SID being 86.6 to 89.0%, 87.5 to 90.5%, 82.7 to 88.2%, and 90.2 to 94.6%, respectively, as dietary CP increased from 68 to 214 g/kg. There were linear increases in AID of N, Arg, Gly, Ile, Lys, Ser, Thr, Tyr, and Val (P ≤ 0.05) as CP increased and linear decreases in SID of N and all AA measured in this study except Lys, Met, and Pro (P ≤ 0.05). Both linear and quadratic effects were observed in AID for Pro (P < 0.05). In conclusion, the protein content of corn-soybean meal diets evaluated in the current study affected SID of most indispensable and dispensable AA, excluding Lys, Met, and Pro.

Tape stripping on a human nail: quantification of removal

BACKGROUND/PURPOSE

Tape stripping is commonly used to investigate the stratum corneum (SC). This study assesses if protein quantitative tape stripping method was suitable for human nails.

METHOD

We used a colorimetric method to quantify proteins removed by the tape. Water barrier functions as a result of tape stripping were also observed by changes in transonychial water loss (TOWL) from the baseline.

RESULTS

Using tape stripping, we observed no difference between nails in the protein quantity removed by tape stripping (P=0.39). The mean TOWL before and after tape stripping were 6.9 and 9.3 g/m2/h, respectively; this was significantly increased in tape stripped nails (P<0.0001).

CONCLUSION

Tape stripping seems to be an effective method to extract proteins from human nail plate and may aid the study of nail structure and function. Further studies are needed to extend our results in terms of age, gender, ethnicity and disease.

Skin decontamination of glyphosate from human skin in vitro

This study compared three model decontaminant solutions (tap water, isotonic saline, and hypertonic saline) for their ability to remove a model herbicide (glyphosate) from an in vitro human skin model. Human cadaver skin was dosed (approximately 375microg) of [14C]-glyphosate on 3cm2 per skin. After each exposure time (1, 3, and 30min post-dosing, respectively), the surface skin was washed three times (4ml per time) with each solution. After washing, the skin was stripped twice with tape discs. Lastly, the wash solutions, strippings, receptor fluid, and remainder of skin were liquid scintillation analyzer counted to determine the amount of glyphosate. There were no statistical differences among these groups at any time points. The total mass balance recovery at three time exposure points was between 94.8% and 102.4%. The wash off rates (glyphosate in wash solutions) at three different exposure times is 79-101.2%. Thus the three tested decontaminants possess similar effectiveness in removing glyphosate from skin. This in vitro model is not only economic and rapid, but also provides quantitative data that may aid screening for optimal decontaminants.

Percutaneous Penetration Enhancers: An Overview

Transdermal drug delivery is the controlled release of drugs through the skin to obtain therapeutic levels systematically. Several technological advances have been made in the recent decades to enhance percutaneous drug penetration. This overview focuses on the physical, biochemical, and chemical means of penetration enhancement, as well as the classification and mechanisms of chemical penetration enhancers, their application in transdermal drug delivery, and trends and development in penetration enhancement.

In vitro model for decontamination of human skin: Formaldehyde

Decontamination of a chemical from skin is often an emergency measure. This study utilized an in vitro model to compare the decontamination capacity of three model decontaminant solutions (tap water, isotonic saline, and hypertonic saline). Human cadaver skin was dosed (approximately 0.25 microg on 3 cm(2) per skin) with radio-labeled [(14)C]-formaldehyde. After a defined exposure time (1, 3, and 30 min post-dosing, respectively), the surface skin was washed three times (4ml per time) with each solution. After washing, the skin was stripped with tape discs twice. Lastly, the wash solutions, strippings, receptor fluid, and remainder of skin were liquid scintillation analyzer counted to determine the amounts of formaldehyde. Additionally, an evaporation test at different exposure times (1min, 3min, 15min, 30min, and 60min, respectively) was conducted to monitor formaldehyde % evaporation. There were no statistical differences among these groups except isotonic saline, at 3min post-exposure (in wash solutions), showed a significantly difference (p<0.05) when compared to tap water. Formaldehyde % evaporation increased linearly with extending application times, and were 7.7%, 13.6%, 19.7%, 24.4%, and 35.9% (1min, 3min, 15min, 30min, and 60min, respectively). This data suggests that isotonic saline may be effective in removing formaldehyde from skin. However, results from this model need validation in vivo. The model may provide a facile and robust method of accelerating knowledge of decontamination mechanism and lead to enhanced efficacy.

Evaluation of the Antioxidant Capacity and Preventive Effects of a Topical Emulsion and Its Vehicle Control on the Skin Response to UV Exposure

Supplying topical exogenous antioxidants to the skin may prevent or minimize free radical-induced damaging. This study determines antioxidative capacity of a topical skin care emulsion (an oil-in-water vitamin E-containing formulation) versus its vehicle on human skin that was exposed to ultraviolet radiation (UVR) by utilizing a photochemiluminescence device and biophysical methods. Ten healthy Caucasians (3 male and 7 female; mean age 47 +/- 10 years) were enrolled. In a randomized and double-blind manner, a pH-balanced vitamin E emulsion or its vehicle control was applied onto predesignated forearm prior to UVR exposure. Thirty minutes after application, these test sites were exposed to a UV light to induce the minimal erythema dose. One untreated site served as a blank control. Visual scoring and instrumental measurements were recorded at baseline and at 24 h and 48 h thereafter. At day 3, after completing instrumental measurements, each test site was stripped three times in a consecutive manner with a proprietary adhesive tape disc. These tapes were quantified for antioxidant capacity using a photochemiluminescence device. Vitamin E emulsion and vehicle control significantly (p < 0.05) suppressed visual scores when compared with blank control at day 2 and day 3 after UV exposure. However, vitamin E emulsion showed significantly (p < 0.05) lower visual scores when compared with vehicle control at day 2 and day 3 after UV exposure.Also,vitamin E emulsion and its vehicle control significantly (p < 0.05) diminished skin color measurement (a*) values when compared with blank control at day 2 and day 3 after UV exposure. At day 2 after UV exposure, only vitamin E emulsion significantly (p < 0.05) reduced skin blood flow volume when compared with blank control. Vitamin E emulsion and its vehicle control showed significant (p < 0.05) reduction of blood flow volume when compared with blank control at day 3 after UV exposure. Vitamin E emulsion and its vehicle control proved effective in preventing induction of erythema and reducing inflammatory damage caused by UV exposure. The effect of vitamin E emulsion exceeded that of an 'active control'.

Cutaneous bioassay of salicylic acid as a keratolytic

Keratolytic efficacy of topical preparations containing salicylic acid was studied in humans utilizing adhesive tape stripping and quantifying SC removal by protein analysis. In combination with tape stripping, squamometry was used to evaluate the influence of salicylic acid on skin surface scaliness and desquamation. Furthermore, skin barrier perturbation and skin irritancy was recorded and related to the dermatopharmacological effect of the preparations. In contrast to squamometry, tape stripping combined with protein analysis was sensitive in detecting keratolytic effect of salicylic acid within hours of application. Importantly, whereas the pH of the preparations only minimally influenced efficacy, local dermatotoxicity was significantly increased at acidic pH. This indicates that the quest to increase the amount of free, non-dissociated SA is, in fact, counterproductive as the more acidic preparations resulted in skin irritation and barrier disruption.

Hydrating effects of a corticoid oil formulation and its vehicle on human skin

Factors in the treatment of atopic dermatitis include restoring skin moisture and reducing inflammation. This study evaluated a corticoid oil formulation and its components with respect to their skin hydration potential. Ten healthy Caucasians were enrolled. Five test sites on the left and right forearm of each subject were tested: one site served as a normal skin control (without treatment), whereas four were wetted by spraying distilled water (approximately 0.1 ml) over a 3-cm2 skin surface area, and spraying was repeated every 5 min for a total of three applications. Five minutes after the final application, 0.2 ml of the corticoid oil formulation, moisturizing vehicle, and plain peanut oil were applied to each pre-designated site (3 cm2); one site was kept as a blank control (water saturation only). Thirty minutes later, test sites were gently wiped with paper tissues, and visual scoring, transepidermal water loss (TEWL), and capacitance were recorded and repeated at 2 and 3 h. The corticoid oil formulation, plain peanut oil, and moisturizing vehicle significantly increased skin hydration 30 min after each single application, with no statistically significant difference among the treatments at any point. The corticoid oil formulation and plain peanut oil slightly but not significantly elevated TEWL 30 min after application. The results support intuitive dermatologic judgment of advising patients to apply moisturizing medicaments after bathing.

Provocative use test of nickel coins in nickel-sensitized subjects and controls

BACKGROUND

Consensus exists on levels of nickel release that are well tolerated in exposure to nickel-containing items in direct and continuous contact with skin (e.g. watches). The clinical relevance of nickel-containing coins eliciting nickel dermatitis associated with extensive occupational exposure (e.g. coins handled by cashiers) has not been determined.

OBJECTIVES

To examine whether nickel-containing coins might be an elicitor of allergic contact dermatitis (ACD) in occupational settings with extensive exposure to coins (i.e. cashiers).

METHODS

Eighteen subjects (10 nickel sensitized and eight non-nickel sensitized) completed this study after screening of history, physical examination and diagnostic patch testing (5% nickel sulphate). Each volunteer handled 10 coins (nickel-containing coins or non-nickel-containing coins) in a cross-over design at 5-min intervals (5 min handling followed by 5 min rest) for 8 h per day, for a total of 12 days excluding the weekend. One hand was gloved while the other was not during coin handling. Visual scoring and bioengineering measurements were recorded at each of four predetermined sites at baseline (day 1), end of day 5 and day 12 (last day of exposure).

RESULTS

There were no statistical differences for either visual or bioengineering data comparing: (i) nickel-sensitized vs. non-nickel-sensitized subjects handling nickel-containing coins at day 1, day 5 and day 12; (ii) day 12 vs. day 1 (baseline) for nickel-sensitized subjects handling nickel-containing coins; (iii) handling of nickel-containing coins vs. non-nickel-containing coins by nickel-sensitized subjects at day 5 and day 12; (iv) gloved hand vs. ungloved hand of nickel-sensitized subjects handling nickel-containing coins at day 12. Limitations of the method and clinical extrapolation are detailed.

CONCLUSIONS

Individuals handling these nickel-containing coins daily did not develop ACD, as judged by visual signs or bioengineering parameters.

Multidrug-resistance-associated protein MGr1-Ag is identical to the human 37-kDa laminin receptor precursor

We report the isolation and functional characterization of the gene encoding MGr1-Ag, a multidrug-resistance-associated protein. A lambdagt11 cDNA library derived from colorectal carcinoma SW480 cells was screened with monoclonal antibody MGr1. DNA homology analysis of 22 positive clones (designated R1-R22) suggested human 37-kDa laminin receptor precursor (37LRP, R7/R9/R15/R16/R19/R20) and a novel gene (R22) as candidate genes encoding MGr1-Ag. Western blot analysis showed that anti-R20 serum reacted with a unique protein band that was consistent with MGr1-Ag, while anti-R22 serum could not react with MGr1-Ag. The coding gene for MGr1-Ag was amplified using reverse transcription-PCR. Sequence analysis revealed that the MGr1-Ag and 37LRP genes shared the same coding sequence. An in vitro drug sensitivity assay indicated that down-regulation of 37LRP by an antisense technique could significantly enhance the cytotoxicity of anticancer drugs to gastric cancer cells. Thus we draw the conclusion that MGr1-Ag is identical to 37LRP.