Prenatal Ultrasound Diagnosis of Megalencephaly-Polymicrogyria-Polydactyly-Hydrocephalus Syndrome with Persistent Hyperplastic Primary Vitreous: A Case Report

INTRODUCTION

Megalencephaly-polymicrogyria-polydactyly-hydrocephalus (MPPH) syndrome is a rare autosomal dominant disorder characterized by megalencephaly (i.e., overgrowth of the brain), polymicrogyria, focal hypoplasia of the cerebral cortex, and polydactyly. Persistent hyperplastic primary vitreous (PHPV) involves a spectrum of congenital ocular abnormalities that are characterized by the presence of a vascular membrane behind the lens.

CASE PRESENTATION

Here, we present a case of foetal MPPH with PHPV that was diagnosed using prenatal ultrasound. Ultrasound revealed the presence of megalencephaly, multiple cerebellar gyri, and hydrocephalus. Whole-exome sequencing confirmed the mutation of the AKT3 gene, which led to the consideration of MPPH syndrome. Moreover, an echogenic band with an irregular surface was observed between the lens and the posterior wall of the left eye; therefore, MPPH with PHPV was suspected.

CONCLUSION

MPPH syndrome with PHPV can be diagnosed prenatally.

Preliminary study of short-term outcomes and learning curves of robotic-assisted THA: comparison between closed platform robotic system and open platform robotic system

BACKGROUND

Both closed platform and open platform robotic-assisted total hip arthroplasty (THA) have recently been recommended as a viable treatment option for achieving accurate positioning of components. Yet, limited studies paid attention to the differences between the closed platform robotic system and the open platform robotic system. Hence, this study aimed to investigate clinical outcomes, radiographic outcomes, complication rates and learning curve of two systems.

MATERIALS AND METHODS

We retrospectively included 62 patients (31 closed robotic system and 31 open robotic system) who underwent THA between February 2021 and January 2023. The demographics, operating time, cup positioning, complications and hip Harris score were evaluated. Learning curves of operation time was conducted using cumulative sum (CUSUM) analysis.

RESULTS

There were no differences in surgical time (76.7 ± 12.1 min vs. 72.3 ± 14.8 min), estimated blood loss (223.2 ± 13.2 ml vs. 216.9 ± 17 ml) and Harris Hip score (HHS) between closed platform robotic system and the open platform robotic system. The closed robotic system and the open robotic system were associated with a learning curve of 9 cases and 7 cases for surgical time respectively, based on the satisfying rate of Lewinnek's safe zone outliers (1/31, 96.8%) and no occurrence of complication. Both robotic systems had significant reduction in overall surgical time, the duration of acetabulum registration, and estimated blood loss between learning phase and proficiency phase.

CONCLUSION

The authors suggest that the surgical outcomes and safe zone outlier rate of the open robotic-assisted THA were similar to those of the closed robotic-assisted THA. These two robotic-assisted are associated with comparable learning curves and both have the precise positioning of acetabular component. From learning phase to proficiency phase, the rate of positions within the safe zone differed only marginally (88.9-100% vs. 85.7-100%) based on a rather low number of patients. This is not a statistically significant difference. Therefore, we suggest that THA undergoing with the robotic-assisted system is the relatively useful way to achieve planned acetabular cup position so far.

Prenatal diagnosis of fetal conotruncal defects by using 2D ultrasound and HD live flow combined with spatiotemporal image correlation

INTRODUCTION

To explore the diagnostic value of spatiotemporal image correlation (STIC) for different types of fetal conotruncal defects (CTDs).

METHODS

The clinical data and STIC images of 174 fetuses with CTDs diagnosed via prenatal ultrasound were analyzed retrospectively.

RESULTS

Among the 174 cases of CTDs, 58 were tetralogy of Fallot (TOF); 30, transposition of great arteries (TGA) (D-TGA, 23 cases; cc-TGA, 7 cases); 26, double outlet of the right ventricle (DORV); 32, persistent arterial trunk (PTA) (type A1, 15 cases; type A2, 11 cases; type A3, 5 cases; type A4, 1 case); and 28, pulmonary atresia (PA) (ventricular septal defect, 24 cases; ventricular septal integrity, 4 cases). Among the cases, 156 were complicated with complex congenital intracardiac and extracardiac malformations. The abnormal display rate of the four-chamber view of two-dimensional echocardiography was low. The display rate of the permanent arterial trunk was the highest (90.6%) in STIC imaging.

CONCLUSIONS

STIC imaging can be used in the diagnosis of different types of CTDs, especially in persistent arterial trunks, and thus has great value for the clinical treatment and prognosis of these defects.

Hepatitis B Virus Surface Antigen Promotes Stemness of Hepatocellular Carcinoma through Regulating MicroRNA-203a

BACKGROUND AND AIMS

Patients with persistent positive hepatitis B surface antigen (HBsAg), even with a low HBV-DNA load, have a higher risk of hepatocellular carcinoma (HCC) than those without HBV infection. Given that tumor stemness has a critical role in the occurrence and maintenance of neoplasms, this study aimed to explore whether HBsAg affects biological function and stemness of HCC by regulating microRNA, and to explore underlying mechanisms.

METHODS

We screened out miR-203a, the most significant down-regulated microRNA in the microarray analysis of HBsAg-positive samples and focused on that miRNA in the ensuing study. In vitro and in vivo functional experiments were performed to assess its regulatory function. The effect of miR-203a on stemness and the possible correlation with BMI1 were analyzed in this study.

RESULTS

MiR-203a was significantly down-regulated in HBsAg-positive HCC with the sharpest decrease shown in microarray analysis. The negative correlation between miR-203a and HBsAg expression was confirmed by quantitative real-time PCR after stimulation or overexpression/knockdown of HBsAg in cells. We demonstrated the function of miR-203a in inhibiting HCC cell proliferation, migration, clonogenic capacity, and tumor development in vivo. Furthermore, the overexpression of miR-203a remarkably increases the sensitivity of tumor cells to 5-FU treatment and decreases the proportion of HCC cells with stem markers. In concordance with our study, the survival analysis of both The Cancer Genome Atlas database and samples in our center indicated a worse prognosis in patients with low level of miR-203a. We also found that BMI1, a gene maintains the self-renewal capacity of stem cells, showed a significant negative correlation with miR-203a in HCC specimen (p<0.001). Similarly, opposite BMI1 changes after overexpression/knockdown of miR-203a were also confirmed in vitro. Dual luciferase reporting assay suggested that miR-203a may regulate BMI1 expression by direct binding.

CONCLUSIONS

HBsAg may promote the development of HCC and tumor stemness by inhibiting miR-203a, resulting in poor prognosis. miR-203a may serve as a crucial treatment target in HBsAg-positive HCC. More explicit mechanistic studies and animal experiments need to be conducted as a next step.

The role of routine postoperative laboratory tests following hip hemiarthroplasty for an elderly femoral neck fracture

Background

Performing postoperative laboratory tests following joint arthroplasty is a regular practice. However, the role of routine postoperative laboratory tests in primary hip arthroplasty is currently in doubt. This study aimed to assess the role of routine postoperative laboratory tests for femoral neck fractures in elderly patients who underwent hip hemiarthroplasty and to evaluate the risk factors for postoperative laboratory testing abnormalities and related interventions.

Methods

This retrospective study reviewed 735 consecutive patients with femoral neck fractures (FNFs) who underwent hip hemiarthroplasty at a single tertiary academic organization. Patient characteristic features and laboratory testing values were recorded. Logistic regression models were calculated to identify risk factors.

Results

A total of 321 elderly patients (> 75 years of age) were ultimately enrolled for analysis. Abnormal postoperative laboratory tests were found in 265 patients (82.6%). Only a minority of the included patients (7.5%) needed medical intervention to treat postoperative laboratory testing abnormalities. Multivariate logistic regression analysis reported that a higher Charlson comorbidity index (CCI) (P = 0.03), abnormal preoperative haemoglobin level (P < 0.01), higher intraoperative blood loss (P < 0.01) and less frequent tranexamic acid use (P = 0.05) were risk factors for abnormal postoperative laboratory tests. Furthermore, a higher CCI has been identified as a risk factor for patients needing clinical interventions related to laboratory abnormalities.

Conclusions

Because 92.5% of laboratory tests did not influence postoperative management, the authors suggest that routine laboratory tests after hip hemiarthroplasty for FNFs are less instructive for the majority of elderly patients. Nevertheless, for patients with identified risk factors, postoperative laboratory tests are still required to identify the abnormalities that need to be managed.

New strain of Pediococcus pentosaceus alleviates ethanol-induced liver injury by modulating the gut microbiota and short-chain fatty acid metabolism

BACKGROUND

Intestinal dysbiosis has been shown to be associated with the pathogenesis of alcoholic liver disease (ALD), which includes changes in the microbiota composition and bacterial overgrowth, but an effective microbe-based therapy is lacking. Pediococcus pentosaceus (P. pentosaceus) CGMCC 7049 is a newly isolated strain of probiotic that has been shown to be resistant to ethanol and bile salts. However, further studies are needed to determine whether P. pentosaceus exerts a protective effect on ALD and to elucidate the potential mechanism.

AIM

To evaluate the protective effect of the probiotic P. pentosaceus on ethanol-induced liver injury in mice.

METHODS

A new ethanol-resistant strain of P. pentosaceus CGMCC 7049 was isolated from healthy adults in our laboratory. The chronic plus binge model of experimental ALD was established to evaluate the protective effects. Twenty-eight C57BL/6 mice were randomly divided into three groups: The control group received a pair-fed control diet and oral gavage with sterile phosphate buffered saline, the EtOH group received a ten-day Lieber-DeCarli diet containing 5% ethanol and oral gavage with phosphate buffered saline, and the P. pentosaceus group received a 5% ethanol Lieber-DeCarli diet but was treated with P. pentosaceus. One dose of isocaloric maltose dextrin or ethanol was administered by oral gavage on day 11, and the mice were sacrificed nine hours later. Blood and tissue samples (liver and gut) were harvested to evaluate gut barrier function and liver injury-related parameters. Fresh cecal contents were collected, gas chromatography–mass spectrometry was used to measure short-chain fatty acid (SCFA) concentrations, and the microbiota composition was analyzed using 16S rRNA gene sequencing.

RESULTS

The P. pentosaceus treatment improved ethanol-induced liver injury, with lower alanine aminotransferase, aspartate transaminase and triglyceride levels and decreased neutrophil infiltration. These changes were accompanied by decreased levels of endotoxin and inflammatory cytokines, including interleukin-5, tumor necrosis factor-α, granulocyte colony-stimulating factor, keratinocyte-derived protein chemokine, macrophage inflammatory protein-1α and monocyte chemoattractant protein-1. Ethanol feeding resulted in intestinal dysbiosis and gut barrier disruption, increased relative abundance of potentially pathogenic Escherichia and Staphylococcus, and the depletion of SCFA-producing bacteria, such as Prevotella, Faecalibacterium, and Clostridium. In contrast, P. pentosaceus administration increased the microbial diversity, restored the relative abundance of Lactobacillus, Pediococcus, Prevotella, Clostridium and Akkermansia and increased propionic acid and butyric acid production by modifying SCFA-producing bacteria. Furthermore, the levels of the tight junction protein ZO-1, mucin proteins (mucin [MUC]-1, MUC-2 and MUC-4) and the antimicrobial peptide Reg3β were increased after probiotic supplementation.

CONCLUSION

Based on these results, the new strain of P. pentosaceus alleviated ethanol-induced liver injury by reversing gut microbiota dysbiosis, regulating intestinal SCFA metabolism, improving intestinal barrier function, and reducing circulating levels of endotoxin and proinflammatory cytokines and chemokines. Thus, this strain is a potential probiotic treatment for ALD.

[Construction of RNA interference (RNAi) lentiviral expression vector of DEK gene and its effect on the biological behavior of liver cancer cells]

Objective: To construct RNA interference (RNAi) lentiviral expression vector of DEK gene, and to explore its effect on the biological behavior of liver cancer cells. Methods: Double-stranded oligo DNAs were annealed and synthesized according to the interference sequence of DEK gene by RNAi technology. Small interfering RNA expression vector pLKO.1 was cloned after enzymatic digestion. The recombinant lentiviral pLKO.1-sh hDEK was constructed, and then the virus supernatant was collected, packed and infected by 293T cells. Real-time reverse transcription PCR (RT-PCR) and Western blot were used to detect DEK expression in human liver cancer cells Bel-7402, Hu-7, SmMC-7721 and HepG2, and DEK knockdown efficiency in each group of lentivirus-infected cells. Cell proliferation ability, cloning ability, apoptosis and migration ability were detected by cell counting kit-8 (CCK8), flow cytometry and scratch test, respectively. The t-test was used to compare the mean between the two groups, and one-way ANOVA was used to compare the multiple groups. Results: Enzymatic digestion and DNA sequencing results confirmed that the recombinant lentiviral vectors pLKO.1-sh hDEK1 and pLKO.1-sh hDEK3 were successfully constructed. RT-PCR and Western blot results showed that the expression of DEK in human liver cancer cells BEL-7402 and Huh7 cells was higher, and pLKO.1-sh hDEK3 was more effective in inhibiting the DEK gene expression (P < 0.05). Therefore, pLKO.1-sh hDEK3 was selected to infect BEL-7402 and Huh7 cells for subsequent functional experiments. CCK8 cell proliferation test result showed that the cell proliferation ability of BEL-7402 and Huh7 cells infected with recombinant lentivirus was weakened when compared with blank control and negative control group (P < 0.05). Apoptosis results showed that the apoptosis rate of knockdown group was higher than that of blank and the negative control group (P < 0.05). Cell scratch test result showed that the wound healing rate of knockdown group was lower than that of blank control and negative control group (P < 0.05), and the difference was statistically significant; however, there was no statistically significant difference between blank control and negative control group. Conclusion: Targeting DEK expression in silent liver cancer cells can inhibit the cell proliferation, migration ability, and induce apoptosis, which lays the foundation for further study of the role of DEK gene in liver cancer.

Epidemiological, clinical and virological characteristics of 74 cases of coronavirus-infected disease 2019 (COVID-19) with gastrointestinal symptoms

OBJECTIVE

The SARS-CoV-2-infected disease (COVID-19) outbreak is a major threat to human beings. Previous studies mainly focused on Wuhan and typical symptoms. We analysed 74 confirmed COVID-19 cases with GI symptoms in the Zhejiang province to determine epidemiological, clinical and virological characteristics.

DESIGN

COVID-19 hospital patients were admitted in the Zhejiang province from 17 January 2020 to 8 February 2020. Epidemiological, demographic, clinical, laboratory, management and outcome data of patients with GI symptoms were analysed using multivariate analysis for risk of severe/critical type. Bioinformatics were used to analyse features of SARS-CoV-2 from Zhejiang province.

RESULTS

Among enrolled 651 patients, 74 (11.4%) presented with at least one GI symptom (nausea, vomiting or diarrhoea), average age of 46.14 years, 4-day incubation period and 10.8% had pre-existing liver disease. Of patients with COVID-19 with GI symptoms, 17 (22.97%) and 23 (31.08%) had severe/critical types and family clustering, respectively, significantly higher than those without GI symptoms, 47 (8.14%) and 118 (20.45%). Of patients with COVID-19 with GI symptoms, 29 (39.19%), 23 (31.08%), 8 (10.81%) and 16 (21.62%) had significantly higher rates of fever >38.5°C, fatigue, shortness of breath and headache, respectively. Low-dose glucocorticoids and antibiotics were administered to 14.86% and 41.89% of patients, respectively. Sputum production and increased lactate dehydrogenase/glucose levels were risk factors for severe/critical type. Bioinformatics showed sequence mutation of SARS-CoV-2 with m⁶A methylation and changed binding capacity with ACE2.

CONCLUSION

We report COVID-19 cases with GI symptoms with novel features outside Wuhan. Attention to patients with COVID-19 with non-classic symptoms should increase to protect health providers.

Transmission risk of patients with COVID-19 meeting discharge criteria should be interpreted with caution

As of Apr. 22, 2020, the World Health Organization (2020) has reported over 2.4 million confirmed coronavirus disease 2019 (COVID-19) patients and 169 151 deaths. Recent articles have uncovered genomic characteristics and clinical features of COVID-19 (Chan et al., 2020; Chang et al., 2020; Guan et al., 2020; Zhu et al., 2020), while our understanding of COVID-19 is still limited. As suggested by guidelines promoted by the General Office of National Health Commission of the People’s Republic of China (2020) (from Versions 1 to 6), discharged standards for COVID-19 were still dependent on viral real-time polymerase chain reaction (RT-PCR) tests of respiratory specimens, showing that recovered COVID-19 patients with twice negative RT-PCR could meet discharge criteria. Here, we examined two cases in which nucleic acid test results were inconsistent with clinical and radiological findings, leading to suboptimal care.

Efficacy of Lactobacillus rhamnosus GG in treatment of acute pediatric diarrhea: A systematic review with meta-analysis

BACKGROUND

Diarrhea is a major infectious cause of childhood morbidity and mortality worldwide. In clinical trials, Lactobacillus rhamnosus GG ATCC 53013 (LGG) has been used to treat diarrhea. However, recent randomized controlled trials (RCTs) found no evidence of a beneficial effect of LGG treatment.

AIM

To evaluate the efficacy of LGG in treating acute diarrhea in children.

METHODS

The EMBASE, MEDLINE, PubMed, Web of Science databases, and the Cochrane Central Register of Controlled Trials were searched up to April 2019 for meta-analyses and RCTs. The Cochrane Review Manager was used to analyze the relevant data.

RESULTS

Nineteen RCTs met the inclusion criteria and showed that compared with the control group, LGG administration notably reduced the diarrhea duration [mean difference (MD) -24.02 h, 95% confidence interval (CI) (-36.58, -11.45)]. More effective results were detected at a high dose ≥ 10¹⁰ CFU per day [MD -22.56 h, 95%CI (-36.41, -8.72)] vs a lower dose. A similar reduction was found in Asian and European patients [MD -24.42 h, 95%CI (-47.01, -1.82); MD -32.02 h, 95%CI (-49.26, -14.79), respectively]. A reduced duration of diarrhea was confirmed in LGG participants with diarrhea for less than 3 d at enrollment [MD -15.83 h, 95%CI (-20.68, -10.98)]. High-dose LGG effectively reduced the duration of rotavirus-induced diarrhea [MD -31.05 h, 95%CI (-50.31, -11.80)] and the stool number per day [MD -1.08, 95%CI (-1.87, -0.28)].

CONCLUSION

High-dose LGG therapy reduces the duration of diarrhea and the stool number per day. Intervention at the early stage is recommended. Future trials are expected to verify the effectiveness of LGG treatment.

Pretreatment With Bacillus cereus Preserves Against D-Galactosamine-Induced Liver Injury in a Rat Model

Bacillus cereus (B. cereus) functions as a probiotic in animals, but the underlying mechanisms remain unclear. We aim to evaluate the protective effects and definite mechanism by which orally administered B. cereus prevents D-galactosamine (D-GalN)-induced liver injury in rats. Twenty-one Sprague–Dawley rats were equally assigned into three groups (N = 7 animals per group). B. cereus ATCC11778 (2 × 10⁹ colony-forming units/ml) was administered to the B. cereus group via gavage, and phosphate-buffered saline was administered to the positive control (PC) and negative control (NC) groups for 2 weeks. The PC and B. cereus groups received 1.1 g/kg D-GalN via an intraperitoneal injection to induce liver injury. The blood, terminal ileum, liver, kidney and mesenteric lymph nodes (MLNs) were collected for histological examinations and to evaluate bacterial translocation. Liver function was also determined. Fecal samples were collected for deep sequencing of the 16S rRNA on an Illumina MiSeq platform. B. cereus significantly attenuated D-GalN-induced liver injury and improved serum alanine aminotransferase (ALT) and serum cholinesterase levels (P < 0.05 and P < 0.01, respectively). B. cereus modulated cytokine secretion, as indicated by the elevated levels of the anti-inflammatory cytokine interleukin-10 (IL-10) in both the liver and plasma (P < 0.05 and P < 0.01, respectively) and the substantially decreased levels of the cytokine IL-13 in the liver (P < 0.05). Pretreatment with B. cereus attenuated anoxygenic bacterial translocation in the veins (P < 0.05) and liver (P < 0.05) and upregulated the expression of the tight junction protein 1. The gut microbiota from the B. cereus group clustered separately from that of the PC group, with an increase in species of the Ruminococcaceae and Peptococcaceae families and a decrease in those of the Parabacteroides, Paraprevotella, and Desulfovibrio families. The potential probiotic B. cereus attenuated liver injury by restoring the gut flora balance and enhancing the intestinal barrier function.

Dynamic alterations in the gut microbiota and metabolome during the development of methionine-choline-deficient diet-induced nonalcoholic steatohepatitis

AIM

To investigate changes in gut microbiota and metabolism during nonalcoholic steatohepatitis (NASH) development in mice fed a methionine-choline-deficient (MCD) diet.

METHODS

Twenty-four male C57BL/6J mice were equally divided into four groups and fed a methionine-choline-sufficient diet for 2 wk (Control 2w group, n = 6) or 4 wk (Control 4w group, n = 6) or the MCD diet for 2 wk (MCD 2w group, n = 6) or 4 wk (MCD 4w group, n = 6). Liver injury, fibrosis, and intestinal barrier function were evaluated after 2 and 4 wk of feeding. The fecal microbiome and metabolome were studied using 16s rRNA deep sequencing and gas chromatography-mass spectrometry.

RESULTS

The mice fed the MCD diet presented with simple hepatic steatosis and slight intestinal barrier deterioration after 2 wk. After 4 wk of feeding with the MCD diet, however, the mice developed prominent NASH with liver fibrosis, and the intestinal barrier was more impaired. Compared with the control diet, the MCD diet induced gradual gut microbiota dysbiosis, as evidenced by a marked decrease in the abundance of Alistipes and the (Eubacterium) coprostanoligenes group (P < 0.001 and P < 0.05, respectively) and a significant increase in Ruminococcaceae UCG 014 abundance (P < 0.05) after 2 wk. At 4 wk, the MCD diet significantly reduced the promising probiotic Bifidobacterium levels and markedly promoted Bacteroides abundance (P < 0.05, and P < 0.01, respectively). The fecal metabolomic profile was also substantially altered by the MCD diet: At 2 wk, arachidic acid, hexadecane, palmitic acid, and tetracosane were selected as potential biomarkers that were significantly different in the corresponding control group, and at 4 wk, cholic acid, cholesterol, arachidic acid, tetracosane, and stearic acid were selected.

CONCLUSION

The MCD diet induced persistent alterations in the gut microbiota and metabolome.

Dickkopf-1 expression is associated with tumorigenity and lymphatic metastasis in human hilar cholangiocarcinoma

Dickkopf-1 (DKK1) is involved in tumorigenesis and the invasion of several tumors. However, its biological function in human hilar cholangiocarcinoma (HCCA) has not yet been documented. This study was designed to investigate the clinical significance and biological function of DKK1 in HCCA. The expression of DKK1 was investigated in thirty-seven human HCCA biopsy samples by immunohistochemistry. To further explore the biological effects of DKK1 in HCCA, transient and stable knockdown of DKK1 in two human HCCA cells (QBC939 and FRH0201) were established using small interfering or short hairpin RNA expression vector. In the present study, immunohistochemistry revealed that DKK1 was up-regulated in human HCCA tissues (24/37, 64.9%). High levels of DKK1 in human HCCA correlated with metastasis to the hilar lymph nodes (P=0.038). Genetic depletion of DKK1 in HCCA cells resulted in significantly inhibited proliferation, colony formation and migration compared with controls. Most importantly, DKK1 down-regulation impaired tumor formation capacity of HCCA cells in vivo. Subsequent investigations revealed that β-catenin is an important target of DKK1 and DKK1 exerts its pro-invasion function at least in part through the β-catenin/ matrix metalloproteinase-7 (MMP-7) signaling pathway. Consistently, in human HCCA tissues, DKK1 level was positively correlated with β-catenin and MMP-7 expression, as well as tumor hilar lymphatic metastasis. Taken together, our findings indicate that DKK1 may be a crucial regulator in the tumorigenicity and invasion of human HCCA, DKK1 exerts its pro-invasion function at least in part through the β-catenin/ MMP-7 signaling pathway, suggesting DKK1 as a potential therapeutic target for HCCA.

Alterations and correlations of the gut microbiome, metabolism and immunity in patients with primary biliary cirrhosis

We selected 42 early-stage primary biliary cirrhosis (PBC) patients and 30 healthy controls (HC). Metagenomic sequencing of the 16S rRNA gene was used to characterize the fecal microbiome. UPLC-MS/MS assaying of small molecules was used to characterize the metabolomes of the serum, urine and feces. Liquid chip assaying of serum cytokines was used to characterize the immune profiles. The gut of PBC patients were depleted of some potentially beneficial bacteria, such as Acidobacteria, Lachnobacterium sp., Bacteroides eggerthii and Ruminococcus bromii, but were enriched in some bacterial taxa containing opportunistic pathogens, such as γ-Proteobacteria, Enterobacteriaceae, Neisseriaceae, Spirochaetaceae, Veillonella, Streptococcus, Klebsiella, Actinobacillus pleuropneumoniae, Anaeroglobus geminatus, Enterobacter asburiae, Haemophilus parainfluenzae, Megasphaera micronuciformis and Paraprevotella clara. Several altered gut bacterial taxa exhibited potential interactions with PBC through their associations with altered metabolism, immunity and liver function indicators, such as those of Klebsiella with IL-2A and Neisseriaceae with urinary indoleacrylate. Many gut bacteria, such as some members of Bacteroides, were altered in their associations with the immunity and metabolism of PBC patients, although their relative abundances were unchanged. Consequently, the gut microbiome is altered and may be critical for the onset or development of PBC by interacting with metabolism and immunity.

Notch2 is a crucial regulator of self-renewal and tumorigenicity in human hepatocellular carcinoma cells

The Notch pathway plays an important role in both stem cell biology and cancer. Notch2 was reported to be upregulated in human hepatocellular carcinoma (HCC) tissues. However, the biological function of Notch2 in human HCC cells has not yet been documented. The aim of this study was to investigate its possible function on the progression of human HCC cells. The expression of Notch2 was detected in four human HCC cell lines by western blotting. Next, Notch2 was knocked down by small interference RNA (siRNA) in human HCC cells. The role of Notch2 in human HCC cells was investigated by cell proliferation assay, colony formation assay, chemoresistance and xenograft formation assay. In the present study, western blotting revealed that the expression of Notch2 was upregulated in human HCC cell lines. Genetic depletion of Notch2 in HCC cells not only resulted in significantly inhibited proliferation, cell cycle progression and colony formation ability but also increased its sensitivity to 5-fluorouracil (5-FU) compared with controls. In addition, upregulation of Notch2 was discovered in CD90 positive HCC cells, CD90 is a marker of hepatic stem cells. Most importantly, knockdown of Notch2 in HCC cells impaired the tumor formation in vivo. Taken together, our findings indicate that Notch2 may confer stemness properties in HCC; downregulation of Notch2 inhibited the proliferation and tumor formation of HCC cells and increase their sensitivity to 5-FU, suggesting Notch2 as a potential therapeutic target for HCC.

Dysregulation of Bmi1 promotes malignant transformation of hepatic progenitor cells

Adult hepatic progenitor cells (HPCs) are involved in a wide range of human liver diseases, including hepatocellular carcinoma (HCC). Bmi1 has been reported to have vital roles in stem cell self-renewal and carcinogenesis. We have previously demonstrated that Bmi1 is upregulated in HCC with bile duct tumor thrombi, a subtype of HCC characterized by profuse expression of hepatic stem cell markers. However, the function of Bmi1 in HPCs has not yet been well elucidated. The current study was designed to investigate the effects of Bmi1 on the biological properties of rat HPCs. To accomplish this, Bmi1 was silenced or enhanced in two HPC cell lines (WB-F344 and OC3) by, respectively, using either small interfering RNA against Bmi1 or a forced Bmi1 expression retroviral vector. The biological functions of Bmi1 in HPCs were investigated through cell proliferation assays, colony-formation assays, cell cycle analysis and invasion assays, as well as through xenograft-formation assays. In this study, genetic depletion of Bmi1 repressed cell proliferation, colony formation and invasion in both assessed HPC cell lines relative to controls. Conversely, forced expression of Bmi1 in two HPCs cell lines promoted cell proliferation, colony formation and invasion in vitro. Aldehyde dehydrogenase (ALDH) assay revealed a significant increase in the number of ALDH-positive cells following the forced expression of Bmi1 in HPCs. Most importantly, transplantation of forced Bmi1 expression HPCs into nude mice resulted in the formation of tumors with histological features of poorly differentiated HCC. Taken together, our findings indicate that forced expression of Bmi1 promotes the malignant transformation of HPCs, suggesting Bmi1 might be a potential molecular target for the treatment of HCC.

Cloning, characterization, and expression of cadmium-induced metallothionein-2 gene from earthworm Pheretima aspergillum (E. Perrier)

Metallothioneins (MTs) are ubiquitous metal-binding, cysteine-rich proteins, associated with metal accumulation and thus providing protection against toxic heavy metals such as cadmium (Cd). To investigate the mechanisms of enrichment of Cd in the earthworm Pheretima aspergillum, we isolated and cloned metallothionein-2 (MT-2) cDNA (538 bp) from P. aspergillum, analyzed its sequence, and examined MT-2 transcription levels by relative quantitative real-time PCR under different concentrations of Cd. The sequence of P. aspergillum MT-2 cDNA and its putative amino acid sequence were highly similar to sequences from other earthworms. The induction with Cd increased the MT-2 gene transcription level in a dose-dependent manner. In addition, earthworm recombinant MT-2 exhibited high Cd bioaccumulation ability in vitro. These results suggested that MT-2 plays an important role in tolerance and accumulation of Cd in P. aspergillum.

Clinicopathological analysis of 12 patients with autoimmune pancreatitis

Autoimmune pancreatitis (AIP) is a rare type of chronic pancreatitis that is often misdiagnosed as pancreatic cancer (PaC). This study was undertaken to investigate the clinicopathological characteristics of AIP, in order to improve the diagnosis and treatment of the disease. Among the 271 patients with PaC who underwent pancreatoduodenectomy between January 2003 and December 2012 at the Sun Yat-Sen Memorial Hospital, chronic pancreatitis was identified and tissue samples obtained from 16 patients. The clinicopathological and imaging characteristics of 16 of the patients with chronic pancreatitis were analyzed retrospectively. The expression of immunoglobulin G4 (IgG4) in the pancreas tissue was detected by immunohistochemistry. Immunohistochemistry showed that IgG4 was highly expressed in 12 out of the 16 patients, and those 12 patients were diagnosed with AIP. Among those 12 patients, 6 presented with emaciation and 7 with jaundice and abdominal pain, respectively. Among the 16 included patients, 12 had an elevated level of serum γ-glutamyltransferase and 9 had an elevated level of serum carbohydrate antigen 19-9. The imaging features were as follows: Pancreatic enlargement in 11 patients (particularly pancreatic head enlargement), pancreatic miniature in 1, 'sausage-like' pancreatic changes in 4 and 'halo' sign pancreatic changes in 5. Massive plasma cell infiltration (11/12) and parenchymal fibrosis (8/12) were observed in the pancreatic tissues through pathology. These results suggest that combining imaging with IgG4 expression for the purpose of diagnosis can enhance the preoperative diagnostic value and reduce the rate of AIP misdiagnosis.

Role of anti-angiogenesis therapy in the management of hepatocellular carcinoma: The jury is still out

As the leading cause of disease-related deaths, cancer is a major public health threat worldwide. Surgical resection is still the first-line therapy for patients with early-stage cancers. However, postoperative relapse and metastasis remain the cause of 90% of deaths of patients with solid organ malignancies, including hepatocellular carcinoma (HCC). With the rapid development of molecular biology techniques in recent years, molecularly targeted therapies using monoclonal antibodies, small molecules, and vaccines have become a milestone in cancer therapeutic by significantly improving the survival of cancer patients, and have opened a window of hope for patients with advanced cancer. Hypervascularization is a major characteristic of HCC. It has been reported that anti-angiogenic treatments, which inhibit blood vessel formation, are highly effective for treating HCC. However, the efficacy and safety of anti-angiogenesis therapies remain controversial. Sorafenib is an oral multikinase inhibitor with anti-proliferative and anti-angiogenic effects and is the first molecular target drug approved for the treatment of advanced HCC. While sorafenib has shown promising therapeutic effects, substantial evidence of primary and acquired resistance to sorafenib has been reported. Numerous clinical trials have been conducted to evaluate a large number of molecularly targeted drugs for treating HCC, but most drugs exhibited less efficacy and/or higher toxicity compared to sorafenib. Therefore, understanding the mechanism(s) underlying sorafenib resistance of cancer cells is highlighted for efficiently treating HCC. This concise review aims to provide an overview of anti-angiogenesis therapy in the management of HCC and to discuss the common mechanisms of resistance to anti-angiogenesis therapies.

Association of Notch1 with vasculogenic mimicry in human hepatocellular carcinoma cell lines

BACKGROUND AND AIMS

According to recent findings, some tumor cells function as endothelial progenitor cells to initiate tumor vasculogenesis, known as "vasculogenic mimicry" (VM). Notch1, the key regulator of vasculogenesis and embryonic differentiation, has shown a correlation with a poor prognosis in hepatocellular carcinoma (HCC). We attempted to elucidate the relationship between Notch1 and the vascularization of HCC.

MATERIALS AND METHODS

HCC cell lines were assayed for tube formation and low-density lipoprotein (LDL) absorption. The translation level of targets of interest was verified using western blot. Notch1 was silenced in HepG2, BEL-7402 and HCCLM6 using lentivirus shRNA. A hypoxic culture was conducted in an anaerobic culture chamber to induce VM in HepG2. Samples from 53 patients with HCC, i.e., 5 with metastasis and 48 without were tested for Notch1(+) cells and CD34 negative plus Periodic Acid-Schiff (PAS) positive structures, respectively.

RESULTS

BEL-7402 and HCCLM6 were capable of tube formation and LDL absorption in vitro, while HepG2 was negative for both. Notch1 down-regulation suppressed endothelial marker expression and greatly impaired tube formation. After hypoxic culture, the tube formation capacity of HepG2 was significantly enhanced, along with an increase in Notch1 expression. Notch1 was strongly and profusely expressed in all 5 cases of distant metastasis, while 19 of the 48 cases without metastasis were sparsely positive (P < 0.05). Notch1 positivity was mainly seen in the cytoplasm and nuclei. VM structures were only found in 2 cases from the metastasis group (P < 0.05).

CONCLUSIONS

HCC is capable of VM. Notch1 might serve as a potential target for VM development in HCC.

Clinicopathological significance of aberrant Notch receptors in intrahepatic cholangiocarcinoma

Notch signaling has been reported to be activated to promote biliary epithelial cell differentiation and tubulogenesis during bile duct development. In this study, clinicopathological significance of aberrant expression of Notch receptors in intrahepatic cholangiocarcinoma (ICC) was investigated. Thus, forty-one ICC specimens were examined by immunohistochemistry using anti-Notch1-4 antibodies, respectively. Expression of Notch receptors was scored by percentage of positive tumor cells and intensity of immunostaining. Clinicopathological parameters and survival data were compared with the expression of Notch receptors, respectively. Expression of Notch receptors was identified in cancer cells, as well as in non-neoplastic cells. Compared with adjacent non-tumor liver tissues, Notch1 and 4 were up regulated, and Notch2 and 3 were relatively weaker. Positive immunostaining of Notch1 in ICC cells was detected in 34 cases (82.9%), Notch2 in 23 (56.1%), Notch3 in 16 (39.0%) and Notch4 in 14 (34.1%). Notch1 was overexpressed in cases with tumor size > 5 cm (P = 0.036). Expression of Notch2 was correlated inversely with histological grade (P = 0.016). Overexpression of Notch4 was more common in cases with serum CA125 > 35 U/ml than cases with CA125 ≤ 35 U/ml (P = 0.048). Expression of Notch3 was not correlated with any other clinicopathological parameters. Moreover, Notch4 was related to poor survival (P < 0.001). To conclude, this study reveals that aberrant expression of Notch receptors 1 and 4 might play important roles during ICC progression.

Notch1 is overexpressed in human intrahepatic cholangiocarcinoma and is associated with its proliferation, invasiveness and sensitivity to 5-fluorouracil in vitro

The Notch signaling pathway has been reported to play crucial roles in inhibiting hepatocyte differentiation and allowing formation of intrahepatic bile ducts. However, little is known about its significance in intrahepatic cholangiocarcinoma (ICC). The aim of the present study was to investigate the effects of Notch1 expression in ICC tissues and cells. The expression of Notch1 was examined in paraffin-embedded sections of ICC (n=44) by immunohistochemistry. Notch1 was knocked down by RNA interference (RNAi) in cultured ICC cells (RBE and HCCC-9810). The proliferation, invasiveness and sensitivity to 5-fluorouracil (5-FU) were detected by Cell Counting Kit-8 (CCK-8), colony formation assays, Transwell assays and flow cytometry, respectively. The expression levels of several multidrug resistance (MDR)-related genes, MDR1-P-glycoprotein (ABCB‑1), breast cancer resistance protein (ABCG‑2) and the multidrug resistance protein isoform 1 (MRP‑1), were examined by quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting. Notch1 was overexpressed in cell membranes and cytoplasm of ICC compared with the adjacent liver tissue (35/44, 79.5%) and this was more common in cases with tumor size≥5 cm (p=0.021) and HBs-Ag positive (p=0.018). By silencing Notch1, the proliferation and invasiveness of ICC cells were inhibited and the inhibition rate of 5-FU was markedly increased. In addition, IC50 values of 5-FU in RBE cells were decreased from 148.74±0.72 to 5.37±0.28 µg/ml and the corresponding values for HCCC-9810 cells were 326.92±0.87 to 42.60±0.35 µg/ml, respectively. Furthermore, Notch1 silencing clearly increased the percentage of apoptotic cells treated by 5-FU compared with the control. Notch1 knockdown led to diminished expression levels of ABCB‑1 and MRP‑1. Therefore, Notch may play important roles in the development of ICC. Silencing Notch1 can inhibit the proliferation and invasiveness of ICC cells and increase their sensitivity to 5-FU in vitro.

Comparative and joint analyses of gene expression profiles under drought and rewatering in Arabidopsis

Drought is a major limiting factor in crop production. Rewatering is a process opposite to drought, allowing plants to recover to their normal physiological state. To understand more thoroughly the set of genes involved in plant response to drought, we comparatively and jointly analyzed the microarray data of drought and rewatering experiments in Arabidopsis. A total of 3833 differentially expressed genes (DEGs) were identified. Among them, ~74% were proven to be co-regulated by drought and rewatering. Drought and rewatering showed contrary regulatory effects on almost all of these co-regulated genes. Only ~6% of the DEGs were significantly regulated by drought alone, and the remaining ~20% were significantly regulated by rewatering alone. However, gene ontology analysis suggested that those "rewatering-only" genes also appeared to be related, either directly or indirectly, to drought response.

Dopamine D1 receptor activation in the medial prefrontal cortex prevents the expression of cocaine sensitization

This study examined whether microinjection of the full D1 agonist, SKF 81297, or the D1 antagonist, SCH 23390, into the medial prefrontal cortex (mPFC) would alter the expression phase of cocaine sensitization. Male Sprague-Dawley rats were administered saline or cocaine (15 mg/kg, i.p.) once per day for seven consecutive days. After 8 to 17 days withdrawal, rats received a bilateral intra-mPFC microinjection of SKF 81297: either 0, 0.03, 0.1, or 0.3 microg/side; SCH 23390: either 0, 0.1, 0.3, or 1.0 microg/side; or a combination of 0.1 microg of SKF 81297 + 0.3 microg of SCH 23390, followed by an i.p. saline or cocaine (15 mg/kg, i.p.) injection. In naïve rats, vertical activity was elevated by the two lower doses of SKF 81297. A similar enhancement of cocaine-induced activity was observed in daily saline rats at the highest dose tested. In contrast, SKF 81297 suppressed the expression of sensitization to cocaine. This blockade of sensitization was prevented by coinfusion of SCH 23390. Infusion of SCH 23390 alone into the mPFC in daily saline and cocaine-pretreated rats demonstrated a suppression of cocaine-induced locomotion in daily saline-pretreated rats after the highest dose, but a slight augmentation of activity after the lowest dose in daily cocaine-pretreated rats. These results demonstrate a contribution by mPFC D1 receptors in the expression of cocaine sensitization and further suggest that the effects of D1 receptor activation in the mPFC occur in opposite directions in daily saline versus daily cocaine-pretreated rats.

Exposure to repeated low-level formaldehyde in rats increases basal corticosterone levels and enhances the corticosterone response to subsequent formaldehyde

Low-level exposure to volatile organic compounds may produce symptoms in humans reporting multiple chemical sensitivity (MCS) through altered hypothalamic-pituitary-adrenal (HPA) axis functioning. We determined whether repeated formaldehyde (Form) exposure would alter corticosterone (CORT) levels in a rat model of MCS. Male Sprague-Dawley rats were given acute chamber exposures to Air or Form (0.7 or 2.4 ppm), and trunk blood was collected 20 or 60 min later. All groups showed increased CORT levels above naïve basal levels at 20 min and a return to baseline by 60 min, with no differences between treatment groups. The second experiment examined the effect of repeated Form exposure (1 h/day x 5 days/week x 2 or 4 weeks) on basal CORT levels and after a final challenge. Basal CORT was increased above naïve values after 2 week exposure to Air or 0.7 ppm Form. By 4 week, CORT levels in the Air group returned to naïve values, but remained elevated in the 0.7 ppm Form group. There were no differences in basal CORT levels among either 2.4 ppm exposed groups. After a final Air or Form challenge, the 2 and 4 week Air and 0.7 ppm Form groups had elevated CORT levels similar to their acute response, while the 2 and 4 week 2.4 ppm Form groups had elevated CORT levels compared to their acute response, indicating enhanced reactivity of the HPA axis to subsequent Form. These findings suggest that altered HPA axis functioning occurs after repeated low-level Form exposure, and may have implications for mechanisms mediating MCS in humans.

I-stepholidine facilitates inhibition of mPFC DA receptors on subcortical NAc DA release

AIM

To determine whether the D1 agonistic action of (-)-stepholidine (SPD) on the medial prefrontal cortex (mPFC) neuron is involved in the modulation of evoked subcortical dopamine (DA) release from nucleus accumbens (NAc) of rats.

METHODS

With the microinjection of SPD into the mPFC, the ventral tegmental area (VTA)-stimulated or amphetamine (AMP)-evoked DA efflux in the NAc was detected by microdialysis + HPLC-ECD in the 6-hydroxydopamine (6-OHDA)-lesioned and intact rats.

RESULTS

The depletion of DA in the mPFC did not modify both the basal level and the VTA-stimulated DA efflux in the NAc, but significantly facilitated the AMP (20 mumol.L-1)-evoked DA efflux within the NAc. It indicates that the mPFC DA system is involved in the regulation of evoked DA release in the NAc. Besides, the AMP-evoked increase of the extracellular DA release in the NAc was significantly attenuated by SPD (10, 30 mmol.L-1) microinjection into the mPFC, though this injection of SPD could not alter the response of DA release by the stimulation of the VTA. Furthermore, the inhibitory effect of SPD on the AMP-evoked DA efflux could be partially reversed by intravenous administration of D1 antagonist Sch-23390 (1 mg.kg-1), but not by D2 antagonist spiperone.

CONCLUSION

SPD is capable of enhancing the function of D1 receptors in the mPFC, by which it facilitates the inhibition of DA release in the NAc.

Differential effects of L-deprenyl on MPP+- and MPTP-induced dopamine overflow in microdialysates of striatum and nucleus accumbens

The present studies investigated the effects of L-deprenyl, 1-methyl-4-phenylpyridinium ion (MPP+) and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) on the efflux of dopamine and its metabolites in microdialysates of striatum and nucleus accumbens in rats. L-Deprenyl or L-amphetamine perfusion into striatum had no effects on basal dopamine efflux, though L-deprenyl reduced the basal efflux of dihydroxyphenylacetic acid and homovanillic acid. MPP+ or MPTP perfusion into striatum significantly increased the dopamine efflux, and the action of MPTP was more potent than that of MPP+. Pretreatment with L-deprenyl antagonized the actions of MPP+ and MPTP. The striatal dopamine efflux of rats was gradually restored by itself after the overflow caused by 2-h perfusion of the dopaminergic neurotoxins, while L-deprenyl could not accelerate the recovery. Perfusion with L-deprenyl or L-amphetamine, but not pargyline, into nucleus accumbens increased the dopamine efflux in a dose-dependent fashion, which could be antagonized by haloperidol pretreatment. MPP+ or MPTP perfusion into nucleus accumbens also increased the dopamine efflux, and the action of MPTP was also more potent than that of MPP+. Pretreatment with L-deprenyl could not antagonize the actions of MPP+ and MPTP. These findings suggest that L-deprenyl, MPP+ and MPTP induce differential effects on nigrostriatal and mesolimbic dopaminergic pathways in vivo. L-Deprenyl has neuroprotective rather than neurorestorative action against MPP+- and MPTP-induced dopamine overflow from striatum. Further, L-deprenyl-induced dopamine overflow from nucleus accumbens may explain the amphetamine-like reinforcing property of L-deprenyl.

Involvement of monoamine oxidase inhibition in neuroprotective and neurorestorative effects of Ginkgo biloba extract against MPTP-induced nigrostriatal dopaminergic toxicity in C57 mice

The present study investigated the neuroprotective and neurorestorative effects of Ginkgo biloba extract (EGb 761) and its two components ginkgolides A (BN52020) and B (BN52021) in mice. 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) (30 mg/kg/d i.p. for six days) significantly reduced striatal dopamine (DA) levels in C57 mice measured by high performance liquid chromatography with electrochemical detection (HPLC-EC). When C57 mice were pretreated with EGb 761 (20, 50, 100 mg/kg/d i.p.) for 7 days and then treated with the same extract 30 min before MPTP injection for 6 days, the neurotoxic effect of MPTP was antagonized in a dose-dependent fashion. Similar treatment with ginkgolides A and B (5, 10, 50 mg/kg/d i.p.) showed no protective effect. When C57 mice were treated with EGb 761 (50 mg/kg/d i.p.) after MPTP-lesion, the recovery of striatal dopamine (DA) levels was accelerated. However, similar treatment with ginkgolides A or B (10 mg/kg/d i.p.) did not show any effect. EGb 761, but not ginkgolides A and B, nonselectively inhibited mouse brain MAO activity in vitro (IC50 = 36.45 +/- 1.56 microg/ml) tested by an improved fluorimetric assay. The results demonstrate that EGb 761 administered before or after MPTP treatment effectively protects against MPTP-induced nigrostriatal dopaminergic neurotoxicity and that the inhibitory effect of EGb 761 on brain MAO may be involved in its neuroprotective effect.

Immunosuppressive effects of dihydroetorphine, a potent narcotic analgesic, in dihydroetorphine-dependent mice

The immunomodulatory effects of dihydroetorphine were systematically investigated in subchronically treated mice. In a dose-dependent fashion, dihydroetorphine (total doses at 444.5, 889 and 1778 microg/kg) lowered the increase of body weight, decreased the weight of the spleen and thymus, weakened the delayed-type hypersensitivity, reduced the generation of antibody-forming cells, inhibited splenic lymphocyte proliferation induced by concanavalin A and lipopolysaccharide, suppressed the production of interleukin-2 in the supernatant of splenocytes induced by concanavalin A, and depleted the ratio of CD4+ and CD8+ subpopulations. Moreover, the physical dependence on dihydroetorphine was also evaluated to confirm that the immunosuppression was concomitant with the addiction to the drug. These results demonstrate that subchronic treatment with dihydroetorphine dose dependently suppresses both humoral and cell-mediated immune function, and that the immunosuppressive effects of dihydroetorphine are much more potent than those of morphine.

Neuroprotective rather than neurorescue or neurorestorative effect of selegiline against MPTP-induced dopaminergic toxicity

AIM

To study the neuroprotective, neurorescue, neurorestorative effects of selegiline (Sel) on nigrostriatal dopaminergic neuronal system and its inhibition of brain monoamine oxidase B (MAO-B).

METHODS

The striatal levels of dopamine and its metabolites were measured using HPLC with electrochemical detection (HPLC-EC). The inhibition of MAO-B was tested by an improved fluorimetric assay.

RESULTS

1-Methyl-4-phenyl-1,2,3,6-tetrahydro-pyridine (MPTP) (30 mg.kg-1 i.p.) reduced the striatal dopamine level by 73% in mice. Selegiline (Sel, 10 mg.kg-1 i.p.) before, but not after, MPTP treatment protected against MPTP-induced nigrostriatal dopaminergic neurotoxicity. There were no differential effects between Sel and saline treatments on the recovery of striatal dopamine levels, which were partially restored during 2 wk. 1-Methyl-4-phenylpyridinium (MPP+) (5 mg.kg-1 i.p.) produced no dopaminergic neurotoxicity. Furthermore, Sel selectively and irreversibly inhibited mouse brain MAO-B in vitro (IC50 = 17 nmol.L-1, 95% confidence limits = 14-20 nmol.L-1).

CONCLUSION

Selegiline has neuroprotective rather than neurorescue or neurorestorative effects on MPTP-induced nigrostriatal dopaminergic neuronal degeneration, which is directly pertinent to its selective and irreversible inhibition of brain MAO-B activity.

The amphetamine-like reinforcing effect and mechanism of L-deprenyl on conditioned place preference in mice

The present study investigated the reinforcing effect of L-deprenyl on conditioned place preference in mice and its mechanism. Conditioned place preference was induced by 10 and 25 mg/kg L-deprenyl in a dose-dependent fashion during five consecutive conditioning days, and its reinforcing property was about five-fold less potent than that of L-amphetamine. Pretreatment with the dopamine antagonist, haloperidol (1 mg/kg i.p.), effectively blocked the place preference produced by L-deprenyl (10 and 25 mg/kg i.p.) and L-amphetamine (2 and 5 mg/kg i.p.), but haloperidol itself produced no place aversion. The neurotoxin, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), 30 mg/kg did not modify the place preference induced by both L-deprenyl and L-amphetamine, though the dopamine concentration in striata assayed by high performance liquid chromatography with electrochemical detection (HPLC-EC) was significantly reduced. These results suggest that L-deprenyl has amphetamine-like reinforcing properties. The reinforcing effect of L-deprenyl may be mediated by central dopaminergic neuronal systems, while the nigrostriatal dopaminergic pathway is not involved.

Time-related mapping of quantitative trait loci underlying tiller number in rice

Using time-related phenotypic data, methods of composite interval mapping and multiple-trait composite interval mapping based on least squares were applied to map quantitative trait loci (QTL) underlying the development of tiller number in rice. A recombinant inbred population and a corresponding saturated molecular marker linkage map were constructed for the study. Tiller number was recorded every 4 or 5 days for a total of seven times starting at 20 days after sowing. Five QTL were detected on chromosomes 1, 3, and 5. These QTL explained more than half of the genetic variance at the final observation. All the QTL displayed an S-shaped expression curve. Three QTL reached their highest expression rates during active tillering stage, while the other two QTL achieved this either before or after the active tillering stage.

Image contrast enhancement based on a histogram transformation of local standard deviation

The adaptive contrast enhancement (ACE) algorithm, which uses contrast gains (CG's) to adjust the high-frequency components of images, is a well-known technique for medical image processing. Conventionally, the CG is either a constant or inversely proportional to the local standard deviation (ILSD). However, it is known that conventional approaches entail noise overenhancement and ringing artifacts. In this paper, we present a new ACE algorithm that eliminates these problems. First, a mathematical model for the LSD distribution is proposed by extending Hunt's image model. Then, the CG is formulated as a function of the LSD. The function, which is nonlinear, is determined by the transformation between the LSD histogram and a desired LSD distribution. Using our formulation, it can be shown that conventional ACE's use linear functions to compute the new CG's. It is the proposed nonlinear function that produces an adequate CG resulting in little noise overenhancement and fewer ringing artifacts. Finally, simulations using some X-ray images are provided to demonstrate the effectiveness of our new algorithm.

Involvement of mu-opioid receptors and alpha-adrenoceptors in the immunomodulatory effects of dihydroetorphine

The present study investigated the effects of acutely administered dihydroetorphine on mitogen-stimulated lymphocyte proliferation and lymphokine production in mice. These immune functions were significantly suppressed by dihydroetorphine at 24 microg/kg and 128 microg/kg in a dose-dependent fashion. This study further examined the involvement of micro-opioid receptors and alpha-adrenoceptors in the immunomodulatory effects of dihydroetorphine. The micro-opioid receptor antagonist, naloxone (4 mg/kg), and alpha-adrenoceptor antagonist, phentolamine (10 mg/kg), but not the beta-adrenoceptor antagonist, propranolol (10 mg/kg), effectively blocked dihydroetorphine-induced suppression of splenic lymphocyte proliferation and lymphokine production. These results demonstrate that dihydroetorphine has significant immunosuppressive effects in mice and the mechanisms of these effects may lie in its interactions with opioid receptors and adrenergic pathways.

Immunosuppressive effects of intravenous self administration of dihydroetorphine on lymphocyte functions in rats

AIM

To study the effects of dihydroetorphine (DHE) on lymphocyte functions in rats and to further assess the abuse potential of DHE.

METHODS

An intravenous self administration (SA) procedure in rats was used to determine the SA liability of DHE. Concanavalin A (Con A)-stimulated lymphocyte proliferation and lymphokine production of rat splenocytes were measured.

RESULTS

DHE 178 +/- 13 micrograms established a stable and typical rat model of psychological dependence, suppressed lymphocyte proliferation (129 +/- 11 Bq) compared with control group (620 +/- 36 Bq), and inhibited the activity of interleukin-2 (IL-2) (A570 = 0.28 +/- 0.06) compared with control group (A570 = 0.51 +/- 0.03).

CONCLUSION

DHE had a high abuse potential and inhibited the Con A-induced lymphocyte proliferation and interleukin-2 production in rats.

Joint mapping of quantitative trait loci using F2 populations

In this paper, the theory of joint mapping of quantitative trait loci is extended to F2 populations. Two independent regression equations, related to the additive and dominance effects respectively, are derived. Therefore, there are three alternative strategies for mapping QTLs, called additive-based mapping (ABM), dominance-based mapping (DBM) and additive-dominance-based mapping (ADBM). Simulation results have shown that ADBM is the most appropriate in most situations.

Model fitting and model testing in the method of joint mapping of quantitative trait loci

A previous paper proposed a new method of QTL mapping called joint mapping (JM). Some problems have been found in model fitting and model testing due to the neglect of the correlations among different observations of the dependent variable in this model. The present paper reports a method of solving the problems. The coefficient of correlation between two observations of the dependent variable is derived. A generalized least square (GLS) approach is developed for model fitting and a strategy and procedure of model testing based on a chi-square test is suggested. A simulated example is given. The example shows that the JM method is quite efficient in mapping multiple linked QTLs.

Rotation and gray-scale transform-invariant texture classification using spiral resampling, subband decomposition, and hidden Markov model

This paper proposes a new texture classification algorithm that is invariant to rotation and gray-scale transformation. First, we convert two-dimensional (2-D) texture images to one-dimensional (1-D) signals by spiral resampling. Then, we use a quadrature mirror filter (QMF) bank to decompose sampled signals into subbands. In each band, we take high-order autocorrelation functions as features. Features in different bands, which form a vector sequence, are then modeled as a hidden Markov model (BMM). During classification, the unknown texture is matched against all the models and the best match is taken as the classification result. Simulations showed that the highest correct classification rate for 16 kinds of texture was 95.14%

A new approach for mapping quantitative trait loci using complete genetic marker linkage maps

A new approach based on nonlinear regression for the mapping of quantitative trait loci (QTLs) using complete genetic marker linkage maps is advanced in this paper. We call the approach joint mapping as it makes comprehensive use of the information from every marker locus on a chromosome. With this approach, both the detection of the existence of QTLs and the estimation of their positions, with corresponding confidence intervals, and effects can be realized simultaneously. This approach is widely applicable because only moments are used. It is simple and can save considerable computer time. It is especially useful when there are multiple QTLs and/or interactions between them on a chromosome.