Diagnostic value of ultrasound elastography for differentiation of benign and malignant axillary lymph nodes: a meta-analysis.

AIM: To investigate the diagnostic value of ultrasound elastography (UE) for benign and malignant axillary lymph nodes. MATERIALS AND METHODS: A literature search was conducted from PubMed, Cochrane EMBASE, and Medline. Fourteen studies including 1,186 patients with 1,411 lymph nodes were enrolled. Overall, diagnostic descriptive statistics included pooled sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) with corresponding 95% confidence intervals (95% CIs) were generated by random effect model. Subgroup analyses were performed in (real-time elastography [RTE] versus shear wave elastography [SWE]) and (conventional ultrasound versus combination of traditional ultrasound and elastography). Meta-regression was used to explore potential sources of heterogeneity. RESULTS: The overall pooled sensitivity, specificity, and AUC of UE was 0.79 (95% CI: 0.71-0.86), 0.90 (95% CI: 0.83-0.95), and 0.91 (95% CI: 0.88-0.93), respectively. In the subgroup analysis of the two UE techniques, the pooled sensitivity, specificity, and AUC of SWE was higher than that of RTE (sensitivity: 0.82>0.77; specificity: 0.91>0.89; AUC: 0.94>0.89). The pooled diagnostic value of ultrasound combined with UE were significantly improving compared with traditional ultrasound (sensitivity: 0.87>0.82, specificity: 0.83>0.78, and AUC: 0.91>0.87). No independent heterogeneous factor was found in meta-regression. CONCLUSION: The results indicate that UE was an effective technique for identifying malignant axillary lymph nodes due to its high diagnostic efficiency, which can provide useful information for surgical procedure selection.

The added value of contrast-enhanced ultrasound to conventional ultrasound in differentiating benign and malignant solid breast lesions: a systematic review and meta-analysis.

AIM: To investigate the added value of contrast-enhanced ultrasound (CEUS) to the conventional ultrasound (US) in the diagnosis of breast lesions. MATERIALS AND METHODS: PubMed, EMBASE, and Web of Science were searched for relevant studies published between 24 May 2005, and 29 October 2017. Studies incorporating CEUS into the conventional US were included. The reference standard was set by means of histopathological findings. The quality assessment of diagnostic studies (QUADAS) instrument was used to assess the quality of the included studies. Meta-Disc version 1.4. was used to calculate the sensitivity, specificity, summary receiver-operating characteristic (sROC) curves, and area under the curve (AUC). Meta-regression with Stata 12.0 was used to compare the diagnostic accuracy of the two techniques. RESULTS: Five studies, comprising 992 patients, were eligible for this meta-analysis. For conventional US, the pooled sensitivity and specificity for were 0.87 (95% confidence interval [CI]: 0.84-0.91) and 0.80 (95% CI: 0.76-0.84), respectively, the AUC was 0.9049. For CEUS-rerated US, the pooled sensitivity and specificity were 0.93 (95% CI: 0.90-0.95) and 0.87 (95% CI: 0.84-0.90). The AUC was 0.9482. Meta-regression showed the sensitivity of CEUS-rerated US did not differ from conventional US (p=0.29), while specificity showed significant difference (p<0.01). There was evidence of between-study heterogeneity regarding sensitivity and specificity for both assessments. CONCLUSIONS: Adding CEUS to conventional US could improve the diagnostic performance in differentiating benign from malignant solid breast lesions, whilst retaining high sensitivity, especially in Breast Imaging-Reporting and Data System (BI-RADS) 3-5 lesions. A uniform standard to distinguish benign from malignant lesions might be needed for further clinical application.

The correlation between miR-200c and the severity of interstitial lung disease associated with different connective tissue diseases.

OBJECTIVES: To explore the correlation between microRNA (miR)-200c and the severity of interstitial lung disease (ILD) associated with connective tissue diseases (CTDs). METHOD: We recruited 218 patients with CTDs who were evaluated with high-resolution computed tomography (HRCT) and the pulmonary function test (PFT). Peripheral blood mononuclear cells (PBMCs) were acquired from 23 patients with systemic sclerosis (SSc), 29 with dermatomyositis/polymyositis (DM/PM), 30 with primary Sjögren's syndrome (pSS), 47 with rheumatoid arthritis (RA), and 23 normal controls to detect the expression level of miR-200c by quantitative reverse transcription polymerase chain reaction (QRT-PCR). miR-200c levels were compared among the different disease groups, between the group with ILD (CTD+ILD) and the group without ILD (CTD-ILD), and between mild and severe ILD groups. Forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) were compared among the different CTD groups and the different CTD+ILD groups. RESULTS: The miR-200c level in the SSc group was significantly higher than in the DM/PM, pSS, and RA groups, and the levels in the DM/PM and pSS groups were significantly higher than in the RA group. The level of miR-200c in the CTD+ILD group was significantly higher than in the CTD-ILD group, and the level in the severe ILD group was significantly higher than in the mild ILD group. FVC and FEV1 were significantly different among the different CTD groups, and among the different CTD+ILD groups. There was a negative correlation between the level of miR-200c and FVC and FEV1. CONCLUSIONS: The level of miR-200c was positively correlated with the severity of ILD, and miR-200c in PBMCs could be a biomarker of the severity of ILD in CTDs.

Correlation of MSH3 polymorphisms with response and survival in advanced non-small cell lung cancer patients treated with first-line platinum-based chemotherapy.

Mismatch repair (MMR) genes, as well as the nucleotide excision repair genes, play an important role in removing cisplatin-DNA adducts, and the mutation of MMR genes in tumors can lead to a decreased response to platinum-based therapies. We examined MutS homolog 3 (MSH3), a mismatch repair gene, and whether polymorphisms of MSH3 were associated with response and survival in advanced non-small cell lung cancer (NCSLC) patients who were treated with platinum-based chemotherapy. The peripheral blood of 180 advanced NCSLC patients who were treated with first-line platinum-based chemotherapy was collected to determine the patients' genotypes of MSH3. The three genotypes of the MSH3 polymorphisms rs26279, rs1650697 and rs1105524 were investigated. A statistically significant association was observed between the polymorphism rs26279 (Ala1054Thr) and sensitivity to platinum-based chemotherapy (P = 0.014). A significant correlation was found between rs1105524 and progression-free survival (PFS), with the G/A and A/A genotypes (median survival time: 14.27 months; 95%CI = 9.80-18.75) suffering shorter survival than patients with the G/G genotype (median survival time: 26.37 months; 95%CI = 15.03-37.71) (P = 0.04). Our results showed that single nucleotide polymorphisms in MSH3 had an impact on the chemotherapy response and prognosis of advanced NCSLC patients who were treated with platinum-based chemotherapy.

The impact of E-cadherin expression on the prognosis of esophageal cancer: a meta-analysis.

E-cadherin is a 120-KD transmembrane calcium-dependent cell adhesion protein that has been demonstrated drownregulated in a large amount of invasive tumors. However, its effect on the prognosis of esophageal cancer (EC) remains controversial. All the relevant English articles that reported survival data or clinicopathological parameters were enrolled in this meta-analysis. A total of 24 studies, including 2691 cases, were included in this study. Twelve studies containing 1669 cases were enrolled to synthesize with hazard ratio (HR) and its 95% confidence interval (CI). The pooled HR for all 12 studies enrolled in this meta-analysis was 1.33 (95% CI 1.16-1.52; z = 3.99, P = 0.00). When the study measured by enzyme-linked immunosorbent assay is excluded, the pooled HR-evaluated E-cadherin to reduce the expression in EC, and in esophageal squamous cell carcinoma was 1.39 (95% CI 1.22-1.58; z = 5.08, P = 0.00) and 1.38 (95% CI 1.21-1.56; z = 4.87, P = 0.00), respectively. The risk of reduced E-cadherin expression on poor differentiation degree was 1.636 (95% CI 1.33-2.02). The pooled odds ratio of reduced E-cadherin expression on deeper tumor invasion, lymph node metastasis, and higher clinical stage were 2.63 (95% CI 1.75-3.94), 1.77 (95% CI 1.06 -2.97), and 3.39 (95% CI 1.85-6.23). Reduced E-cadherin expression detected by immunohistochemistry could be a valid prognostic marker in patients with EC, especially in patients with esophageal squamous cell carcinoma. Reduced E-cadherin expression is significantly associated with poorer differentiation degree.

Down-regulation of long non-coding RNA DUXAP8 suppresses proliferation, metastasis and EMT by modulating miR-498 through TRIM44-mediated AKT/mTOR pathway in non-small-cell lung cancer.

OBJECTIVE: The long non-coding RNA double homeobox A pseudogene 8 (DUXAP8) was reported to be involved in the initiation and development of multiple cancers. However, the detailed biological role of DUXAP8 in non-small-cell lung cancer (NSCLC) remains unclear. Herein, we aimed to explore the biological function and molecular mechanism of DUXAP8 in NSCLC. PATIENTS AND METHODS: The levels of DUXAP8, microRNA-498 (miR-498) and tripartite motif-44 (TRIM44) were detected by Quantitative Real-time polymerase chain reaction (qRT-PCR). The cell proliferation, migration and invasion were detected by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and transwell assays. Protein expression levels were detected by Western blot. The target relationships among DUXAP8, miR-498 and TRIM44 were predicted by starBase2.0 and confirmed using luciferase reporter and RNA pull-down assays. To detect the role of DUXAP8 in vivo, tumor xenografts were created. RESULTS: DUXAP8 and TRIM44 were upregulated in NSCLC tissues and cell lines, while miR-498 was downregulated. Functionally, knockdown of DUXAP8 could repress proliferation, migration, invasion, Epithelial-Mesenchymal Transition (EMT) and phosphorylation of AKT/mTOR in NSCLC cells. This inhibition could be restored by inhibiting miR-498 or overexpressing TRIM44. Furthermore, we also observed a positive correlation between DUXAP8 and TRIM44 expression, while the expressions of miR-498 and DUXAP8, as well as miR-498 and TRIM44, were negatively correlated in NSCLC tissues. Importantly, DUXAP8 could regulate the expression of TRIM44 via miR-498. Moreover, knockdown of DUXAP8 notably decreased the xenograft tumor volume, weight and number of metastatic nodules in vivo. CONCLUSIONS: Our results identified that LncRNA DUXAP8 could regulate cell proliferation, metastasis and EMT in NSCLC cells by inhibiting miR-498 through the activation of TRIM44-mediated AKT/mTOR pathway.

The potential mechanism of INHBC and CSF1R in diabetic nephropathy.

OBJECTIVE: The aim of this study was to research the potential mechanism of INHBC and CSF1R in diabetic nephropathy. MATERIALS AND METHODS: 30 SD rats were selected and randomly divided into Con group, Sham group, and DN group. In the DN group, intraperitoneal injection of the streptozotocin-citrate solution was conducted to construct the DN model. In the Sham group, intraperitoneal injection of equal citrate solution was conducted. The Con group did not do anything. After successful modeling, blood glucose, insulin, biochemical indexes, and levels of inflammatory cytokines in blood samples were detected. The expression levels of INHBC, CSF1R, apoptosis-related proteins and IGF-1 were detected by Western blot. MRNA expression levels of INHBC, CSF1R, IGF-1 and inflammatory cytokines were detected by qPCR. RESULTS: Compared with the Con group, the expression levels of blood glucose, insulin, biochemical indexes, INHBC, CSF1R, IGF-1, IL-6, TNF-α and Bcl2 increased in the DN group, while the expression levels of IL-10, Caspase 3, Caspase 9, and Bax decreased. INHBC mRNA was positively correlated with IGF-1 mRNA. CSF1R was negatively correlated with Caspase 3, Caspase 9, Bax, and IL-10, and positively correlated with IL-6, TNF-α, and Bcl2. CONCLUSIONS: NHBC and CSF1R induced the secretion of IL-6 and TNF-α, inhibited the production of IL-10, inhibited apoptosis of cells, and promoted the proliferation of renal cells during DN disease. Therefore, INHBC and CSF1R can be used as target objects of DN treatment strategies.

Interaction between bone marrow-derived dendritic cells and miR-21 of tubular renal epithelial cells under hypoxia.

OBJECTIVE: To investigate the intracellular response and role of microRNA 21 in the regulation of dendritic cell maturation and function. MATERIALS AND METHODS: Bone marrow-derived DCs (BMDCs) isolated from male C57BL/6J mice and primary renal tubular epithelial cells were used as primary cells to perform this study. Flow cytometry was used to determine BMDCs and analyze the apoptosis effect. Transmission electron microscopy was used for the identification of the diameter of exosomes. Reverse transcription-Polymerase Chain Reaction (RT-PCR) and Western blotting were used to detect the effect after cells were transfected with oligo. ELISA was used to determine the tumor necrosis factor-α (TNF-α), interleukin-12 (IL-12), and IL-1beta in DC supernatants. RESULTS: We found that the upregulation of microRNA 21 in dendritic cells induced by physical hypoxia contributed to decreased expressions of CD80 (cluster of differentiation 80), CD86 (cluster of differentiation 86), and MHCII (major histocompatibility complex class II molecules) of dendritic cells and suppressed secretion of inflammatory cytokines and chemokine receptor type 7. Co-culture with tubular epithelial cells or hypoxia-pretreated tubular epithelial cell-derived conditional medium promoted bone marrow-derived dendritic cell maturation. Exosomes purified from the supernatant of cultured marrow-derived dendritic cells showed upregulated microRNA 21 under hypoxia, whereas anti-microRNA 21 treated tubular epithelial cells promoted co-cultured marrow-derived dendritic cell maturation. CONCLUSIONS: Both oxygen concentration and tubular epithelial cells participate in regulating dendritic cell maturation, directly or indirectly through the microRNA 21 signal pathway.

MiR-99a suppresses cell migration and invasion by regulating IGF1R in gastric cancer.

OBJECTIVE: Gastric cancer is a common kind of gastrointestinal malignancies. Increasing evidence indicates dysregulation of microRNA-99a (miR-99a) in gastric cancer, and has been extensively investigated in terms of cancer formation, progression, diagnosis, therapy, and prognosis. The purpose of this study is to explore how miR-99a worked in gastric cancer on migration and invasion. PATIENTS AND METHODS: The mRNA and protein levels of miR-99a and insulin-like growth factor 1 receptor (IGF1R) in gastric cancer were measured by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) and Western blot. Transwell assay was employed to analyze the migratory and invasive capacities. The Dual-Luciferase reporter assay was performed to confirm miR-99a mediated the expression of IGF1R by directly targeting its mRNA 3'-untranslated regions (3'-UTR) in gastric cancer cells. RESULTS: MiR-99a was discovered to be significantly downregulated while IGF1R was upregulated in gastric cancer tissues and cell lines. The expression of miR-99a had a negative correlation with the IGF1R expression in gastric cancer tissues. Moreover, miR-99a was low expressed in gastric cancer cells HGC-27 and MGC-803 compared to the normal cell line. MiR-99a suppressed the migration and invasion through directly binding to the 3'-UTR of IGF1R mRNA in HGC-27 cells. In addition, IGF1R could reverse partial roles of miR-99a on migration and invasion in gastric cancer. CONCLUSIONS: MiR-99a inhibited the migratory and invasive abilities by regulating the expression of IGF1R. MiR-99a was downregulated while IGF1R was upregulated in gastric cancer cell lines. The newly identified miR-99a/IGF1R axis provides novel insight into the pathogenesis of gastric cancer.

Elevated PHD2 expression might serve as a valuable biomarker of poor prognosis in lung adenocarcinoma, but no lung squamous cell carcinoma.

OBJECTIVE: Using data from The Cancer Genome Atlas (TCGA), we aimed to explore the association between Egl nine homolog 1 (EGLN1/PHD2) expression and survival outcomes in lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC), respectively. PATIENTS AND METHODS: A retrospective study was conducted based on the level-3 data in the Cancer Genome Atlas (TCGA)-LUAD and TCGA-LUSC and data from the Human Protein Atlas (HPA). RESULTS: Both LUAD and LUSC had elevated PHD2 expression compared to their respective adjacent normal tissues. However, Kaplan-Meier survival curves showed that the high PHD2 expression LUAD patients had a significantly shorter overall survival (OS) and recurrence-free survival (RFS) (p=0.001 and p<0.001) compared to the low expression group. However, these differences were not observed in LUSC patients. Univariate and multivariate analysis showed that high PHD2 expression was an independent indicator of unfavorable OS (HR: 1.685, 95%CI: 1.251-2.269, p=0.001) and unfavorable RFS (HR: 2.008, 95%CI: 1.430-2.818, p<0.001) in LUAD patients. The methylation status of two CpG sites (cg07040244 and cg21875980) in PHD2 was at least moderately and negatively correlated with PHD2 expression. High methylation level of these two CpG sites was associated with better OS in LUAD patients. CONCLUSIONS: Elevated PHD2 expression might only serve as a valuable biomarker of poor prognosis in LUAD, but no in LUSC. Cg07040244 and cg21875980 might be two CpG sites modulating PHD2 expression in LUAD.

Precipitation and ultimate pH effect on chemical and gelation properties of protein prepared by isoelectric solubilization/precipitation process from pale, soft, exudative (PSE)-like chicken breast meat1.

Pale, soft, exudative (PSE)-like chicken breast is considered deteriorated raw material in the poultry meat industry that has inferior processing ability. The chemical and gelation properties of PSE-like chicken breast meat paste were studied. These pastes were prepared by the pH adjustment method and protein isolation using the isoelectric solubilization/precipitation (ISP) process from PSE-like chicken meat. The ISP-isolated samples were solubilized at pH 11.0 and recovered at pH 5.5 and 6.2. The ultimate pH of the ISP-isolated protein and meat paste was adjusted to 6.2 and 7.0. The ultimate pH in this article referred to the final pH of the extracted protein and meat paste. Higher reactive sulfhydryl content and surface hydrophobicity were found in the precipitation at pH 6.2 than at pH 5.5. However, various ultimate pH values showed no significant influence on the surface hydrophobicity. The hardness of gel, as measured by textural profile analysis, was improved using 6.2 as the precipitation pH compared with pH 5.5. The viscoelastic modulus (G΄) of gel pastes prior to the thermal gelation was higher with ISP treatment. However, lower G΄ was seen after thermal gelation compared with the control. Dynamic rheological measurement demonstrated a different gel-forming mechanism for protein precipitated at pH values of 5.5 and 6.2 compared with the meat paste. The cooking loss showed that the recovered protein failed to form a gel with good water-retention capacity unless the ultimate pH was adjusted to 7.0. Gels made from protein extracted by the ISP method had higher yellowness and lower redness values, probably due to protein denaturation. Precipitation at pH 6.2 formed a harder gel with lower water-retention ability than that at pH 5.5, and this result was possibly due to higher surface hydrophobicity and S-S bridge formation. Overall, network characteristics of ISP-treated protein gels were strongly dependent on precipitation pH and ultimate pH.

Comparison of imaging value for diabetic lower extremity arterial disease between FBI and CE-MRA.

OBJECTIVE: This study adopted self-control study method to assess the efficacy of fresh blood imaging (FBI) and contrast-enhanced MR angiography (CE-MRA) for patients with diabetic lower extremity arterial disease (DLEAD) (Fontaine stage I to IV), and to evaluate the imaging of lower extremity peripheral arterial disease (PAD) in different stages of diabetes mellitus (DM). PATIENTS AND METHODS: 1. This study recruited 44 diabetic patients with suspected lower extremity PAD to take both FBI and CE-MRA. 2. Two experienced cardiovascular radiologists assessed the image quality, the detection of lower extremity arterial branches, and tissue contamination (veins, arteries, and soft tissues) of FBI and CE-MRA, as well as the presence and severity of stenotic lesions. 3. Statistical differences of the quality of FBI and CE-MRA were determined using paired t-test. 4. Correlation analysis was adopted for determining the direction and strength of the relationship between the changes of the indexes of FBI and the different Fontaine stages. RESULTS: 1. The quality evaluation results of the image of lower extremity arteries from the 44 diabetic patients indicated no statistically significant difference between FBI and CE-MRA in the patients with Fontaine stage I-III (p >0.05). However, a statistically significant difference was observed in the patients with Fontaine stage IV (p <0.05), and the quality of FBI was slightly worse. 2. Arterial branches that observed from FBI and CE-MRA were 885 and 904, respectively. There was no statistically significant difference for the arterial branches between FBI and CE-MRA in the patients with Fontaine stage I-III (p >0.05). However, a statistically significant difference was observed in the patients with Fontaine stage IV (p <0.05), and CE-MRA indicated more artery branches than FBI. 3. There was a statistically significant difference for the evaluation of venous contamination between FBI and CE-MRA (p <0.05), and there was less venous contamination using FBI. 4. The study results indicated that with Fontaine stages going on the FBI's image quality and arterial branches reduced gradually, and the degree of tissue interference and arteriostenosis was rising gradually. CONCLUSIONS: The results of this study indicated that using FBI in lower extremity PAD of diabetics had good quality and high diagnostic accurancy, and the tissue contamination (veins and soft tissues of calf) was effectively avoided. Especially in Fontaine stage I-III, FBI can be used as an alternative technique of CE-MRA, and it also can be used in diabetic patients with renal impairment in Fontaine IV.

Enhancing mammary differentiation by overcoming lineage-specific epigenetic modification and signature gene expression of fibroblast-derived iPSCs.

Recent studies have shown that induced pluripotent stem cells (iPSCs) retain a memory of their origin and exhibit biased differentiation potential. This finding reveals a severe limitation in the application of iPSCs to cell-based therapy because it means that certain cell types are not available for reprogramming for patients. Here we show that the iPSC differentiation process is accompanied by profound gene expression and epigenetic modifications that reflect cells' origins. Under typical conditions for mammary differentiation, iPSCs reprogrammed from tail-tip fibroblasts (TF-iPSCs) activated a fibroblast-specific signature that was not compatible with mammary differentiation. Strikingly, under optimized conditions, including coculture with iPSCs derived from the mammary epithelium or in the presence of pregnancy hormones, the fibroblast-specific signature of TF-iPSCs obtained during differentiation was erased and cells displayed a mammary-specific signature with a markedly enhanced ability for mammary differentiation. These findings provide new insights into the precise control of differentiation conditions that may have applications in personalized cell-based therapy.

Urinary apolipoprotein M could be used as a biomarker of acute renal injury: an ischemia-reperfusion injury model of kidney in rat.

BACKGROUND: It has been well documented that apolipoprotein M (apoM) is principally expressed in hepatocytes as well as renal tubular epithelial cells. The importance of apoM in the kidney is unknown. In the present study we examined urinary any apoM after short-term ischemia-reperfusion injury (IRI) of kidney in a rat model. METHODS: The kidneys of 11 male Sprague-Dawley rats were rendered ischemic for 45 minutes followed by different intervals of reperfusion. Serum and urine apoM concentrations were determined using a dot-blot analysis with specific rabbit anti-human apoM antibodies that cross-react with rat apoM. Serum concentrations of blood urea nitrogen (BUN) and creatinine (Cr) were determined using standard clinical automated analyses. RESULTS: BUN was significantly elevated after 45 minutes of ischemia followed by 24 hours of reperfusion; serum Cr concentrations were also significantly increased at 6 and 24 hours of reperfusion. Interestingly, similar to BUN and Cr, serum apoM concentrations were significantly increased after ischemia for 45 minutes alone and after 2 hours of reperfusion. Urinary apoM concentrations were obviously increased after 2 h as well as 6 hours of reperfusion. CONCLUSION: apoM showed characteristics of an acute-phase reactive protein; its occurrence in urine may be considered to be a biomarker of acute renal injury.

Chemical constituents of the brown alga Dictyopteris divaricata.

A novel sesquiterpene-substituted benzoic acid, named dictyvaric acid (1), together with nine known compounds (2-10), have been isolated from the brown alga Dictyopteris divaricata Okam. The structure of 1 was elucidated as 3-[(decahydro-2-hydroxy-2,5,5,8a-tetramethyl-1-naphthalenyl)-methyl]-4-hydroxybenzoic acid by spectroscopic methods, including IR, FABMS, HR-FABMS, 1D and 2D NMR techniques. All compounds were obtained from this species for the first time.

Molecular cloning and characterization of the cathepsin B-like proteinase from the cotton boll worm, Helicoverpa armigera.

An enzyme purified from the ovaries of Helicoverpa armigera, as an active form with molecular mass of 30 kDa on SDS-PAGE, was identified as a cysteine proteinase because it could be inhibited by E-64, a specific inhibitor of cysteine proteinase, and required reducing conditions for activity. This enzyme was further identified as a cathepsin B-like cysteine proteinase by partial amino acid sequencing. A cDNA encoding this proteinase was cloned from H. armigera, using degenerate primers and RACE techniques. Results of Northern blots indicated that the mRNA encoding the proteinase was transcribed in the ovaries, the fat bodies of female and male adults, pupae and in the larvae. No mRNA was detected from the larval epidermis or from the midgut. Hence, transcription of the cathepsin B-like cysteine proteinase from H. armigera was tissue-specific, but not gender- or developmental stage-specific. However, proteolytic activities were only detected from ovaries, and adult female and male fat bodies. No activity was observed from pupal and larval fat bodies, from the larval epidermis or from the midgut. Only one form of mRNA of approximately 1100 bases was detected, and in situ hybridization showed that the transcripts were distributed in the adult female fat bodies, follicular cells and the oocytes. Since the proteinase expressed in ovaries was able to degrade vitellin in vitro, it may be involved in the degradation of vitellin during embryonic development.

Molecular cloning and expression patterns of the molt-regulating transcription factor HHR3 from Helicoverpa armigera.

Molt-regulating transcription factors, hormone receptor 3 (HR3), play important roles in regulating expression of tissue-specific genes involved in insect molting and metamorphosis. A 1668 bp cDNA encoding a molt-regulating transcription factor (HHR3) was cloned from Helicoverpa armigera, which encodes a protein made up of 556 amino acids. This 62 kDa protein was found to have an isoelectric point (pI) of 6.52. There was no signal peptide or N-glycosylation site found in this cDNA. A DNA-binding region signature of nuclear hormone receptor was found from amino acids 107-133. A possible outside to inside transmembrane helice was found from amino acids 72-90. Northern blots of the larvae revealed five bands of HHR3 named as band 0, 1, 2, 3 and 4 with molecular masses determined as 2.1, 2.6, 3.6, 4.5 and 5.5 kb, respectively. The expression patterns of HHR3 in vivo were variable with developmental stages and tissues. Results showed that band 1-4 of HHR3 was only briefly expressed during molting, which suggested these bands are involved in the regulation of molting cascade, whereas band 0 was expressed in both molting and feeding larvae. Band 1 and 2 of HHR3 could be induced from epidermis of newly molted 6th instar larvae by non-steroidal ecdysone agonist, RH-2485.