Time-domain sound field reconstruction using a rigid spherical microphone array.

A time-domain approach for interior spherical near-field acoustic holography is proposed to achieve the low-delay reconstruction of time-domain sound fields using a rigid spherical microphone array. This reconstruction encompasses the incident pressure field, the incident radial particle velocity field, and the total pressure field, which includes scattering. The proposed approach derives time-domain radial propagators through the inverse Fourier transform of their frequency-domain counterparts. These propagators are then applied to the array measurements to obtain the time-domain spherical harmonic coefficients of the interior sound field. Given the fact that the time-domain radial propagators possess finite-time support and exhibit significant high-frequency attenuation characteristics, they can be efficiently implemented using finite impulse response (FIR) filters. The proposed approach processes the signal sample-by-sample through these FIR filters, avoiding a series of issues associated with time-frequency transformations in frequency-domain methods. As a result, the approach offers higher accuracy and lower latency in reconstructing non-stationary sound fields compared to its frequency-domain counterpart and thus holds greater potential for real-time applications. Additionally, owing to the scattering effect of the rigid sphere, the approach avoids the impact of spherical Bessel function nulls and does not require the measurement of particle velocities, which renders the measurements cost effective.

Comprehensive Analysis of Physiological, Biochemical and Flavor Characteristics Changes in Crucian Carp (Carassius auratus) under Different Concentrations of Eugenol.

Eugenol is a widely used fishery anesthetic. This study investigated the effects of various concentrations of eugenol on blood physiological and biochemical indexes, and muscle flavor, in crucian carp (Carassius auratus). To determine the appropriate concentration of eugenol anesthetic for use in crucian carp transportation and production operations, we evaluated seven anesthesia groups of 20, 30, 40, 50, 60, 70, and 80 mg/L and one control group (without eugenol) to determine the effects on blood physiological and biochemical indexes, and muscle flavor. The red blood cells and platelets of crucian carp decreased significantly (p < 0.05) with eugenol treatment. With increasing eugenol concentration, the white blood cells and hemoglobin did not change significantly, whereas lactate dehydrogenase, alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase increased significantly (p < 0.05). The content of phosphorus, magnesium, and sodium increased after anesthesia, whereas the content of potassium decreased with increasing eugenol concentration. After anesthesia, the content of albumin and total protein in the serum decreased with increasing eugenol concentration (p < 0.05); triglyceride first increased and subsequently decreased (p < 0.05); blood glucose content first increased and then decreased (p < 0.05); and no significant difference was observed in total cholesterol content (p > 0.05). No significant difference was observed in muscle glycogen and liver glycogen content after eugenol anesthesia (p > 0.05). The eugenol-based anesthesia test did not indicate major liver histomorphological effects, but the very small number of gill sheet edema cases observed requires further study. Analysis of electronic nose data indicated that eugenol treatment affected the flavor of the fish. The anesthesia concentration of 20-80 mg/L had some effect on the physiology and biochemistry of crucian carp, thus providing a reference for the application of eugenol in crucian carp transportation and experimental research.

Study on the Regulation Mechanism of Quality Deterioration Due to Chilling Stress and Dry Exposure during Anhydrous Storage and Transportation of Yesso Scallop Patinopecten yessoensis.

In this paper, the quality change of Yesso scallop (Patinopecten yessoensis) in the process of anhydrous storage and transportation after cold acclimation and induced dormancy was studied, and the regulation mechanism of quality degradation during storage and transportation in the process of gradient chilling stress and drying exposure was further explored. The results show that, when transferred from hydrous to anhydrous states, the breathing pattern of the scallops changed from aerobic to anaerobic. Their gill filaments were altered and their apparent vitality constantly declined, which was reflected by the edge shrinkage of the pallium and the direct proportions of the edge reduction rate and the stimulus response period. After being in the anhydrous state for 4 d, the AEC value dropped to 67.59%. At this time, if they were placed under hydration again, the scallops resumed a good growth state. By proteomics analysis, it was revealed that cold acclimation and dry exposure mainly led to changes in biological functions and pathways, such as mitochondrial inner membrane and ATP hydrolysis activity. In addition, it can be seen from the functional annotation and enrichment analysis of the metabolite KEGG that cold acclimation promoted the purine metabolism of scallops, while dry exposure inhibited the metabolism of saturated fatty acids. In this study, the infrared sensing mode was used for the first time, too, in order to record the heart-rate changes of the scallops during circulation, which shows that non-destructive vitality monitoring of Lamellibranchia is feasible.

Effect of Vanillin on the Anaesthesia of Crucian Carp: Effects on Physiological and Biochemical Indices, Pathology, and Volatile Aroma Components.

The anaesthetic effect of vanillin on crucian carp was investigated using different concentrations of vanillin, with a nonvanillin control. The effective concentration range of vanillin anaesthesia was determined from the behavioural characteristics of crucian carp during the anaesthesia onset and recovery phases. Physiological and biochemical indices, and the electronic nose response to the fish muscle, were measured over the range of effectiveanaestheticc concentrations. An increased concentration of vanillin shortened the time taken to achieve deep anaesthesia but increased the recovery time. The levels of white blood cells, red blood cells, haemoglobinn, platelets, alanine aminotransferase, alkaline phosphatase, lactate dehydrogenase, phosphorus, potassium, magnesium, total protein, and serum albumin were lower than the control in the vanillin treatment group. Triglycerides and total cholesterol were not significantly affected. Histology showed no effect of vanillin on the liver, except at 1.00 g/L vanillin. Vanillin resulted in a nondose-responsive effect on the gill tissue, increasing the width and spacing of the gill lamellae. E-Nose analysis of the carp-muscle flavour volatiles was able to distinguish between different vanillin treatment concentrations. GC-IMS identified 40 flavour compounds, including 8 aldehydes, 11 alcohols, 10 ketones, 2 esters, and 1 furan. Vanillin had aanaestheticic effect on crucian carp and these findings provide a theoretical basis for improving the transport and experimental manipulation of crucian carp.

Interaction between serine carboxypeptidase-like protein TtGS5 and Annexin D1 in developing seeds of Triticum timopheevi.

GS5 encoding a serine carboxypeptidase-like protein positively regulates grain size and weight through the regulation of grain width and filling and is helpful in improving cereal yields. Grain width variation determined by GS5 is associated with cell number and size, but the actual underlying mechanism is still unclear. Two orthologs of GS5, TtGS5-3A-G and TtGS5-3G-G, were cloned from the Triticum timopheevi accession no. CWI17006. To identify the proteins that interacted with TtGS5-3A-G and TtGS5-3G-G in premature grains, we performed pull-down assays followed by liquid chromatography-mass spectrometry/mass spectrometry analysis. The analyses revealed 18 proteins were present in both the TtGS5-3A-G and TtGS5-3G-G interactomes. Among five candidates selected, only Annexin D1 interacted with both TtGS5-3A-G and TtGS5-3G-G in yeast. Annexin D1, TtGS5-3A-G, and TtGS5-3G-G were located on the cytoplasmic membranes of Arabidopsis protoplasts and onion epidermal cells, and interactions between Annexin D1 and TtGS5-3A-G, as well as TtGS5-3G-G, were shown by bimolecular fluorescence complementation assays. Annexin D1 was expressed widely in different tissues, and it co-expressed with TtGS5-3A-G/TtGS5-3G-G at the grain enlargement phase. These results indicated that Annexin D1 interacted with TtGS5-3A-G and TtGS5-3G-G in premature grains. Together with the structural similarities of Annexin D1 to known fiber elongation factors, we proposed that TtGS5 might regulate the cell size by interacting with Annexin D1. The results provide significant new information for understanding the roles that GS5 plays in regulating grain size, which may be useful in improving crop yields.

Analyzing the action of evolutionarily conserved modules on HMW-GS 1Ax1 promoter activity.

KEY MESSAGE: The specific and high-level expression of 1Ax1 is determined by different promoter regions. HMW-GS synthesis occurs in aleurone layer cells. Heterologous proteins can be stored in protein bodies. High-molecular-weight glutenin subunit (HMW-GS) is highly expressed in the endosperm of wheat and relative species, where their expression level and allelic variation affect the bread-making quality and nutrient quality of flour. However, the mechanism regulating HMW-GS expression remains elusive. In this study, we analyzed the distribution of cis-acting elements in the 2659-bp promoter region of the HMW-GS gene 1Ax1, which can be divided into five element-enriched regions. Fragments derived from progressive 5' deletions were used to drive GUS gene expression in transgenic wheat, which was confirmed in aleurone layer cells, inner starchy endosperm cells, starchy endosperm transfer cells, and aleurone transfer cells by histochemical staining. The promoter region ranging from - 297 to - 1 was responsible for tissue-specific expression, while fragments from - 1724 to - 618 and from - 618 to - 297 were responsible for high-level expression. Under the control of the 1Ax1 promoter, heterologous protein could be stored in the form of protein bodies in inner starchy endosperm cells, even without a special location signal. Our findings not only deepen our understanding of glutenin expression regulation, trafficking, and accumulation but also provide a strategy for the utilization of wheat endosperm as a bioreactor for the production of nutrients and metabolic products.

Molecular Cloning and Bioinformatics Analysis of DQA Gene from Mink (Neovison vison).

In the present study, we cloned, sequenced, and explored the structural and functional characteristics of the major histocompatibility complex (MHC)-DQA gene from mink (Neovison vison) for the first time. The full-length sequence of DQA gene was 1147-bp-long, contained a coding region of 768-bp, which was predicted to encoding 255 amino acid residues. The comparison between DQA from mink (Neovison vison) and other MHC-DQA molecules from different animal species showed that nucleotide and encoded amino acid sequences of the mink DQA gene exhibited high similarity with the ferret (Mustela pulourius furo). Phylogenetic analysis revealed that mink (Neovison vison) DQA is grouped with that of ferret (Mustela pulourius furo). The cloned sequence contained a 23-amino acid NH2-terminal signal sequence with the signal peptide cutting site located in amino acids 23⁻24, and had three Asn-Xaa-Ser/Thr sequons. Three cysteine residues were also identified (Cys-85, Cys-121, and Cys-138). The 218 to 240 amino acids were predicted to be the transmembrane domains. The prediction of the secondary structure revealed three α-helixes and fourteen ß-sheets in Neovison vison DQA protein, while random coil was a major pattern. In this study, the whole CDS sequence of Neovison vison DQA gene was successfully cloned, which was valuable for exploring the function and antiviral molecular mechanisms underlying the molecule. The findings of the present study have laid the foundation for the disease resistance and breeding of mink.

Effects of high-molecular-weight glutenin subunit combination in common wheat on the quality of crumb structure.

BACKGROUND: High-molecular-weight glutenin subunits (HMW-GSs) have important effects on bread-making quality. Allelic variations of HMW-GS in bread wheat varieties contribute in different ways to dough properties and bread volume. However, no systematic analysis has been done on the effects of allelic variation on bread-crumb structure, an important parameter when evaluating bread-making quality. In this study, seven Glu-1 deletion lines and one intact line harboring different encoding loci and derived from a cross between two spring wheat cultivars were used to investigate the contribution of a single Glu-1 locus, or combination of Glu-1 loci, to the crumb structure. RESULTS: Deletion of HMW-GS locus combinations resulted in a decline in slice size, brightness, and fineness of the bread crumb. A desirable crumb structure correlated well with preferred subunit combinations: high levels of GMPs, superior dough properties, and loaf volume. The effects of the HMW-GS combinations were ranked as Dx5 + Dy10 > Bx17 + By18 > Ax1 + Null. The Ax1 + Null allele affected the crumb structure by interacting with the Bx17 + By18 or Dx5 + Dy10. CONCLUSION: High-molecular-weight glutenin subunits had significant effects on the loaf volume and crumb structure; varying effects from different subunit combinations were observed. © 2018 Society of Chemical Industry.

Neutralizing effect of hemolymph from the shore crab, Thalamita crenata, on paralytic shellfish toxins.

Several species of crabs are resistant to paralytic shellfish toxins (PSTs) and/or pufferfish toxin, tetrodotoxin, regardless of toxification by the toxins. The shore crab Thalamita crenata, which inhabits Leizhou Peninsula, China, is tolerant to PST toxicity, and the hemolymph has neutralizing effects against the lethal activity of PST. In the present study, we investigated the PST neutralizing factors in the hemolymph from T. crenata and successfully separated PST-binding proteins by PST-ligand affinity chromatography. The neutralization factors, obtained in the fraction with a molecular weight over 10 kDa by ultrafiltration, were susceptible to proteases such as alcalase, animal complex proteases, pancreatin, and papain. The PST-binding protein had high dose-dependent neutralization effects on PST toxicity. The PST-binding activity of the protein was stable at 25 °C and then decreased with an increase in temperature; heating at 65 °C for 60 min eliminated the initial activity by two-thirds. The PST-binding activity was strongly inhibited in the presence of Mg(2+) and Ca(2+), but not Na(+) and K(+). The PST-binding capability of the protein differed among PST components in descending order of neosaxitoxin, gonyautoxins 1 and 4, saxitoxin, and gonyautoxins 2 and 3, suggesting a structure-activity relationship in PST binding.

High-level expression of LMW-GS and α-gliadin genes promoted by the expressed tag sequence of 5' end in Escherichia coli.

Wheat storage protein genes, especially low molecular weight glutenin subunit (LMW-GS) and gliadin genes are difficult to be expressed in Escherichiacoli, mainly due to the presence of highly repetitive sequences. In order to establish a high efficiency expression system for these genes, five different expression plasmids combining with 9 genes, viz. 6 LMW-GS and 3 α-gliadin genes isolated from common wheat and related species, were studied for heterologous expression in E. coli. In this study, when an expressed tag sequence encoding signal peptide, His-S or GST-tag was fused to the 5' end of LMW-GS or gliadin gene as the leading sequence, all recombination genes could be stably expressed at a high level. On the contrast, as expected, the inserted genes encoding mature protein failed without an expressed tag sequence. This result indicated that using expressed tag sequences as leading sequences could promote LMW-GS and gliadin genes to be well expressed in E. coli. Further transcriptional analysis by quantitative real-time PCR (qRT-PCR) showed transcription levels of recombination genes (e.g. GST-Glutenin, His-S-Glutenin and SP(∗)-His-Glutenin) were 4-fold to 33-fold higher than those of the LMW-GS genes, which suggested these expressed tag sequences might play an important role in stimulating transcription. The possible molecular mechanism under this phenomenon was discussed.

Screening for toxicity and resistance to paralytic shellfish toxin of shore crabs inhabiting at Leizhou peninsula, China.

The situation of the environment contaminated by paralytic shellfish toxin (PST) in Leizhou peninsula, China, has attracted more attention since seafood poisoning occurred occasionally. In this study, we examined the toxicities of shore crab Leptodius exaratus, Thalamita crenata and Metopograpsus latifrons by mouse assay, resistance to PST by lethal test injection with PST, and discussed the toxicity neutralization of their hemolymph. The results showed 12% of shore crabs possessed toxicity of 4.3-4.4 MU/g. The 100% lethal dose of PST for M. latifrons was about 2 times of those for the other two crab species. The hemolymphs of the crabs were all able to neutralize PST and tetrodotoxin (TTX) toxicity in different extent. The above results indicate shore crabs at this area are exposed to an environment potentially contaminated with PST and/or TTX, and the toxicity neutralizing efficacy of their hemolymph directly affects their resistance to the toxins.

Purification and characterization of curcin, a toxic lectin from the seed of Jatropha curcas.

The seed of the plant Jatropha curcas contains a toxic protein, designated as curcin, which was purified to apparent homogeneity by the combined use of chromatography on Sephdex G-100. The molecular weight of 28.2 kDa and the pI of 8.54 were determined. The protein was found to be a glycoprotein; the total neutral-surge content was 4.91%. It strongly inhibits the protein synthesis of rabbit reticulocyte lysate, with an IC(50) of 0.42 nM. It was determined by Edman that the sequence of the N-terminal thirty-two amino acids was: A-G/Y-S/K-T/A-P/D-T-L-T-I-T-Y-D-A-T/A-A-D-K-K-N-Y-A-Q-F-I-K-D-L-R-E-A-F/A-G. The isolated curcin had a hemagglutinating activity, when its concentration was more than 7.8 mg/L. The secondary structure of curcin was analyzed by Circular Dichroism (CD) spectrum. The result shows the curcin contains alpha-helix (22.3%), beta-sheet (43.5%), and random coil and corner (34.2%). The results of acute toxicity in mice show that mice oral semi-lethal dose LD(50) was 104.737 +/- 29.447 mg/kg; mice parenteral semi-lethal dose LD(50) was 67.20 +/- 10.445 mg/kg.

Diagnostic utility of aberrant methylation of tissue factor pathway inhibitor 2 in pure pancreatic juice for pancreatic carcinoma.

The tissue factor pathway inhibitor 2 (TFPI-2) is a Kunitz-type serine proteinase inhibitor. Recently, the aberrant methylation of TFPI-2 was detected frequently in pancreatic carcinoma (PCa) tissues but not in normal pancreatic tissues. We analyzed the aberrant methylation of TFPI-2 in the pure pancreatic juice (PPJ) aspirated endoscopically from patients with various pancreatic diseases. Using the highly sensitive methylation-specific polymerase chain reaction (MSP) and quantitative MSP (Q-MSP) assay, we investigated the aberrant methylation of TFPI-2 in nine human PCa cell lines and in the PPJ from patients with PCa, intraductal papillary mucinous neoplasms (IPMN) and chronic pancreatitis (CP). The incidence of aberrant TFPI-2 methylation was seven (77.8%) of nine PCa cell lines by Q-MSP. In cell lines, the expression of TFPI-2 mRNA by quantitative reverse transcription-polymerase chain reaction showed an inverse correlation to the aberrant methylation of TFPI-2. The incidence of aberrant TFPI-2 methylation in the PPJ was 21 (58.3%) of 36 PCa patients, three (17.6%) of 17 IPMN and one (4.8%) of 21 CP by MSP assay. Using a suitable cut-off value of 2.5 according to the receiver operating characteristic curve, the incidence of aberrant TFPI-2 methylation in the PPJ by real-time MSP was 18 (62.1%) of 29 PCa patients, one (5.1%) of 17 IPMN and three (14.3%) of 21 CP, respectively. The incidence of quantitative TFPI-2 hypermethylation in the PPJ with PCa was significantly higher than that with IPMN (P < 0.001) or CP (P < 0.001). Moreover, the aberrant methylation rate of TFPI-2 in the PPJ was 100%, as observed (6/6) in the PCa patients with liver metastasis, and 86.7% (26/30) in stages IVa + IVb of PCa by Q-MSP assay. These results suggest that promoter methylation of TFPI-2 in the PPJ may be a useful marker in the diagnosis and progression of PCa using an endoscopically feasible approach.

Aberrant methylation of secreted apoptosis-related protein 2 (SARP2) in pure pancreatic juice in diagnosis of pancreatic neoplasms.

OBJECTIVE: Secreted apoptosis-related protein (SARP) families are considered to counteract the oncogenic Wnt signaling pathway, and inactivation of this gene may aid cancer development and progression. Recently, the aberrant methylation of SARP2 was detected frequently in pancreatic carcinoma (PCa) tissue, but not in normal pancreatic tissue. We evaluated the hypermethylation of SARP2 in pure pancreatic juices (PPJ) aspirated endoscopically from patients with PCa, intraductal papillary mucinous neoplasm of the pancreas (IPMN), chronic pancreatitis (CP), and a control group who were consequently free of pancreatic diseases according to the differential diagnosis of PCa. METHODS: We investigated the aberrant methylation of SARP2 in 9 human PCa cell lines and in the PPJ samples from 33 patients with PCa, 20 with IPMN, 19 with CP, and 10 control patients. DNAs extracted from not only sediment, but also the supernatant of the PPJ and PCa cell lines were treated with sodium bisulfite and analyzed by methylation-specific polymerase chain reaction (PCR) (MSP). Moreover, real-time MSP was also performed for the melting curve analysis and the quantitative analysis of SARP2 in the PPJ. RESULTS: The incidence of the aberrant methylation of SARP2 using MSP was 8/9 (89%) in PCa cell lines, 26/33 (79%) in the PPJ with PCa, and 17/20 (85%) with IPMN. However, it was only 1/19 (5%) in the PPJ with CP, and 0/10 (0%) in the PPJ of the control patients, respectively. The incidences of aberrant methylation of SARP2 in the PPJ with PCa and IPMN were significantly higher than that in the PPJ with CP (P < 0.001, P < 0.001). Melting curve analysis by real-time MSP revealed that the incidences of aberrant methylation of SARP2 in PPJ was 28/33 (85%) with PCa, 9/11 (82%) with the malignant group of IPMN, 5/9 (56%) with the benign group of IPMN and 5/19 (26%) with CP. In this analysis, there were significant differences between PCa and CP (P < 0.001), and between the malignant group of IPMN and CP (P < 0.005). In the quantitative analysis by real-time MSP with a suitable cut-off value, the incidences of aberrant methylation of SARP2 in the PPJ with PCa, the malignant group of IPMN, the benign group of IPMN, and CP were 19/33 (58%), 6/11 (55%), 3/9 (33%), and 2/19 (11%), respectively. The incidence of the aberrant methylation of SARP2 in the PPJ was significantly different between PCa and CP and between the malignant group of IPMN and CP (P < 0.005 and P < 0.05, respectively). CONCLUSIONS: Hypermethylation of SARP2 in the PPJ may be a highly sensitive and useful marker for the detection of pancreatic neoplasms, including PCa and the malignant group of IPMN.

Effect of gemcitabine on the expression of apoptosis-related genes in human pancreatic cancer cells.

AIM: To investigate the expression of genes involved in the gemcitabine-induced cytotoxicity in human pancreatic cancer cells. METHODS: A human pancreatic cancer cell line, PANC-1, was cultured. 1x10(4) PANC-1 cells were plated in 96-well microtiter plates. After being incubated for 24 h, gemcitabine was added to the medium at concentrations ranging 2.5-1000 mg/L. The AlamarBlue dye method was used for cell growth analysis. DNA fragmentation was quantitatively assayed using a DNA fragmentation enzyme-linked immunosorbent assay (ELISA) kit. PAP and TP53INP1 mRNA expression was determined using the reverse transcription-polymerase chain reaction with semi-quantitative analysis. The expression of GSK-3beta and phospho-GSK-3beta proteins was examined with Western blot analysis. RESULTS: The IC50 for the drug after a 48-h exposure to gemcitabine was 16 mg/L. The growth of PANC-1 cells was inhibited by gemcitabine in a concentration-dependent manner (P<0.0001) and the cell growth was also inhibited throughout the time course (P<0.0001). The DNA fragmentation rate in the gemcitabine-treated group at 48 h was 44.7%, whereas it was 25.3% in the untreated group. The PAP mRNA expression was decreased after being treated with gemcitabine, whereas the TP53INP1 mRNA was increased by the gemcitabine treatment. Western blot analysis showed that phospho- GSK-3beta (ser9) was induced by the gemcitabine treatment. CONCLUSION: Gemcitabine suppresses PANC-1 cell proliferation and induces apoptosis. Apoptosis is considered to be associated with the inhibition of PAP and GSK-3beta, and the activation of TP53INP1 and pospho-GSK-3beta (ser9).

Down-expression of tumor protein p53-induced nuclear protein 1 in human gastric cancer.

AIM: Overexpression of tumor protein p53-induced nuclear protein 1 (TP53INP1) induces G1 cell cycle arrest and increases p53-mediated apoptosis. To clarify the clinical importance of TP53INP1, we analyzed TP53INP1 and p53 expression in gastric cancer. METHODS: TP53INP1 and p53 expression were examined using immunohistochemistry in 142 cases of gastric cancer. The apoptosis of gastric cancer cells was analyzed using the TUNEL method. The relationship between the expression of TP53INP1 and clinicopathological factors was statistically analyzed. RESULTS: TP53INP1 was expressed in 98% (139/142 cases) of non-cancerous gastric tissues and was down-expressed in 64% (91/142 cases) of gastric cancer lesions from the same patients. TP53INP1 expression was significantly decreased (43.9%) in poorly differentiated adenocarcinoma compared with well or moderately differentiated adenocarcinoma (81.6%). Cancers invading the submucosa or deeper showed lower positively (59.1%) compared with mucosal cancers (85.2%). Decrease or loss of TP53INP1 expression was significantly correlated with lymphatic invasion (54.3% vs 82.0% without lymphatic invasion) and node-positive patients (31.3% vs 68.3% in node-negative patients). P53 was expressed in 68 (47.9%) patients of gastric cancer, whereas it was absent in normal gastric tissues. A significant association was also observed between TP53INP1 status and the level of apoptosis in tumor cells: the apoptotic index in TP53INP1-positive tissues was significantly higher than that in TP53INP1-negative portions. Finally, when survival data were analyzed, loss of TP53INP1 expression had a significant effect in predicting a poor prognosis (P=0.0006). CONCLUSION: TP53INP1-positive rate decreases with the progression of gastric cancer. TP53INP1 protein negativity is significantly associated with aggressive pathological phenotypes of gastric cancer. TP53INP1 is related to the apoptosis of gastric cancer cells. The decreased expression of the TP53INP1 protein may reflect the malignant grade of gastric cancer and is regarded as an adverse prognostic factor.

Oral vaccination of mice against rodent malaria with recombinant Lactococcus lactis expressing MSP-1(19).

AIM: To construct the recombinant Lactococcus lactis as oral delivery vaccination against malaria. METHODS: The C-terminal 19-ku fragments of MSP1 (MSP-1(19)) of Plasmodium yoelii 265-BY was expressed in L. lactis and the recombinant L. lactis was administered orally to BALB/c and C57BL/6 mice. After seven interval vaccinations within 4 wk, the mice were challenged with P. yoelii 265-BY parasites of erythrocytic stage. The protective efficacy of recombinant L. lactis was evaluated. RESULTS: The peak parasitemias in average for the experiment groups of BALB/c and C57BL/6 mice were 0.8+/-0.4% and 20.8+/-26.5%, respectively, and those of their control groups were 12.0+/-0.8% and 60.8+/-9.6%, respectively. None of the BALB/c mice in both experimental group and control group died during the experiment. However, all the C57BL/6 mice in the control group died within 23 d and all the vaccinated mice survived well. CONCLUSION: The results imply the potential of recombinant L. lactis as oral delivery vaccination against malaria.

Requirement of the N-terminus for dimer formation of phenylalanine-sensitive 3-deoxy-D-arabino-heptulosonate synthase AroG of Escherichia coli.

The first regulatory step in the synthesis of aromatic amino acids is catalyzed by 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase (DAHPS). In Escherichia coli, the allosteric DAHPS exists as three isozymes, AroG, AroF and AroH, each independently feedback-inhibited by corresponding end product amino acids, phenylalanine, tyrosine and typtophan. Structural biological evidences have suggested that the N-terminus of AroG is involved in the formation of a putative inhibitor-binding site and feedback inhibition signal transmission. Our previous work showed that a single amino acid residue replacement Ile10Ala or deletion of 15 N-terminal amino acids could lead to a dramatic loss of AroG enzymatic activity (Hu et al. 2003). Here we demonstrate that the deletion of N-terminus prevents the enzyme from forming a dimeric structure, indicating that the N-terminus of AroG plays a critical role in the formation of the essential tight dimeric structure.

Expression of vacuole membrane protein 1 (VMP1) in spontaneous chronic pancreatitis in the WBN/Kob rat.

OBJECTIVES: VMP1 is a stress-induced gene that is overexpressed in acute pancreatitis. Its overexpression promotes the formation of intracellular vacuoles and cell death. We investigated the expression of VMP1 mRNA and its relation to apoptosis in spontaneous chronic pancreatitis in the WBN/Kob rat. METHODS: Four-week-old male WBN/Kob rats were fed a special breeding diet, MB-3, for 20 weeks. Rats were killed every 4 weeks, and the pancreas was examined. VMP1 mRNA expression was determined by reverse transcriptase polymerase chain reaction with a semiquantitative analysis, direct sequencing, and in situ hybridization. Immunohistochemistry for proliferating cell nuclear antigen (PCNA) and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) were used to detect cell proliferation and apoptosis, respectively. RESULTS: Vacuolar formation was most prominent at 12 weeks, when chronic pancreatitis occurred. VMP1 mRNA was also strongly expressed at 12 weeks. In situ hybridization revealed VMP1 mRNA was expressed in acinar cells. Apoptosis was increased at 12 and 20 weeks, and PCNA expression was strongest at 16 weeks in the course of chronic pancreatitis. CONCLUSIONS: VMP1 mRNA expression paralleled the formation of vacuoles and apoptosis in acinar cells in the course of chronic pancreatitis in WBN/Kob rats.