Engineered CBEs based on Macaca fascicularis A3A with improved properties for precise genome editing

Cytidine deaminase defines the properties of cytosine base editors (CBEs) for C-to-T conversion. Replacing the cytidine deaminase rat APOBEC1 (rA1) in CBEs with a human APOBEC3A (hA3A) improves CBE properties. However, the potential CBE application of macaque A3A orthologs remains undetermined. Our current study develops and evaluates engineered CBEs based on Macaca fascicularis A3A (mA3A). Here, we demonstrate that BE4-mA3A and its RNA-editing-derived variants exhibit improved CBE properties, except for DNA off-target activity, compared to BE3-rA1 and BE4-rA1. Unexpectedly, deleting Ser-Val-Arg (SVR) in BE4-mA3A dramatically reduces DNA and RNA off-target activities and improves editing accuracy, with on-target efficiency unaffected. In contrast, a chimeric BE4-hA3A-SVR+ shows editing efficiency increased by about 50%, with other properties unaffected. Our findings demonstrate that mA3A-based CBEs could provide prototype options with advantages over rA1- and hA3A-based CBEs for further optimization, highlighting the importance of the SVR motif in defining CBE intrinsic properties.

Transcriptome analysis identification of A-to-I RNA editing in granulosa cells associated with PCOS

Background

Polycystic ovary syndrome (PCOS) is a complex, multifactor disorder in women of reproductive age worldwide. Although RNA editing may contribute to a variety of diseases, its role in PCOS remains unclear.

Methods

A discovery RNA-Seq dataset was obtained from the NCBI Gene Expression Omnibus database of granulosa cells from women with PCOS and women without PCOS (controls). A validation RNA-Seq dataset downloaded from the European Nucleotide Archive Databank was used to validate differential editing. Transcriptome-wide investigation was conducted to analyze adenosine-to-inosine (A-to-I) RNA editing in PCOS and control samples.

Results

A total of 17,395 high-confidence A-to-I RNA editing sites were identified in 3,644 genes in all GC samples. As for differential RNA editing, there were 545 differential RNA editing (DRE) sites in 259 genes with Nucleoporin 43 (NUP43), Retinoblastoma Binding Protein 4 (RBBP4), and leckstrin homology-like domain family A member 1 (PHLDA) showing the most significant three 3'-untranslated region (3'UTR) editing. Furthermore, we identified 20 DRE sites that demonstrated a significant correlation between editing levels and gene expression levels. Notably, MIR193b-365a Host Gene (MIR193BHG) and Hook Microtubule Tethering Protein 3 (HOOK3) exhibited significant differential expression between PCOS and controls. Functional enrichment analysis showed that these 259 differentially edited genes were mainly related to apoptosis and necroptosis pathways. RNA binding protein (RBP) analysis revealed that RNA Binding Motif Protein 45 (RBM45) was predicted as the most frequent RBP binding with RNA editing sites. Additionally, we observed a correlation between editing levels of differential editing sites and the expression level of the RNA editing enzyme Adenosine Deaminase RNA Specific B1 (ADARB1). Moreover, the existence of 55 common differentially edited genes and nine differential editing sites were confirmed in the validation dataset.

Conclusion

Our current study highlighted the potential role of RNA editing in the pathophysiology of PCOS as an epigenetic process. These findings could provide valuable insights into the development of more targeted and effective treatment options for PCOS.

Systematic pan-cancer analysis identifies SLC31A1 as a biomarker in multiple tumor types

BACKGROUND

Solute Carrier Family 31 Member 1 (SLC31A1) has recently been identified as a cuproptosis-regulatory gene. Recent studies have indicated that SLC31A1 may play a role in colorectal and lung cancer tumorigenesis. However, the role of SLC31A1 and its cuproptosis-regulatory functions in multiple tumor types remains to be further elucidated.

METHODS

Online websites and datasets such as HPA, TIMER2, GEPIA, OncoVar, and cProSite were used to extract data on SLC31A1 in multiple cancers. DAVID and BioGRID were used to conduct functional analysis and construct the protein-protein interaction (PPI) network, respectively. The protein expression data of SLC31A1 was obtained from the cProSite database.

RESULTS

The Cancer Genome Atlas (TCGA) datasets showed increased SLC31A1 expression in tumor tissues compared with non-tumor tissues in most tumor types. In patients with tumor types including adrenocortical carcinoma, low-grade glioma, or mesothelioma, higher SLC31A1 expression was associated with shorter overall survival and disease-free survival. S105Y was the most prevalent point mutation in SLC31A1 in TCGA pan-cancer datasets. Moreover, SLC31A1 expression was positively correlated with the infiltration of immune cells such as macrophages and neutrophils in tumor tissues in several tumor types. Functional enrichment analysis showed that SLC31A1 co-expressed genes were involved in protein binding, integral components of the membrane, metabolic pathways, protein processing, and endoplasmic reticulum. Copper Chaperone For Superoxide Dismutase, Phosphatidylinositol-4,5-Bisphosphate 3-Kinase Catalytic Subunit Alpha and Solute Carrier Family 31 Member 2 were copper homeostasis-regulated genes shown in the PPI network, and their expression was positively correlated with SLC31A1. Analysis showed there was a correlation between SLC31A1 protein and mRNA in various tumors.

CONCLUSIONS

These findings demonstrated that SLC31A1 is associated with multiple tumor types and disease prognosis. SLC31A1 may be a potential key biomarker and therapeutic target in cancers.

Brain Epitranscriptomic Analysis Revealed Altered A-to-I RNA Editing in Septic Patients

Recent studies suggest that RNA editing is associated with impaired brain function and neurological and psychiatric disorders. However, the role of A-to-I RNA editing during sepsis-associated encephalopathy (SAE) remains unclear. In this study, we analyzed adenosine-to-inosine (A-to-I) RNA editing in postmortem brain tissues from septic patients and controls. A total of 3024 high-confidence A-to-I RNA editing sites were identified. In sepsis, there were fewer A-to-I RNA editing genes and editing sites than in controls. Among all A-to-I RNA editing sites, 42 genes showed significantly differential RNA editing, with 23 downregulated and 19 upregulated in sepsis compared to controls. Notably, more than 50% of these genes were highly expressed in the brain and potentially related to neurological diseases. Notably, cis-regulatory analysis showed that the level of RNA editing in six differentially edited genes was significantly correlated with the gene expression, including HAUS augmin-like complex subunit 2 (HAUS2), protein phosphatase 3 catalytic subunit beta (PPP3CB), hook microtubule tethering protein 3 (HOOK3), CUB and Sushi multiple domains 1 (CSMD1), methyltransferase-like 7A (METTL7A), and kinesin light chain 2 (KLC2). Furthermore, enrichment analysis showed that fewer gene functions and KEGG pathways were enriched by edited genes in sepsis compared to controls. These results revealed alteration of A-to-I RNA editing in the human brain associated with sepsis, thus providing an important basis for understanding its role in neuropathology in SAE.

Repeated Winning and Losing Experiences in Chronic Social Conflicts Are Linked to RNA Editing Pattern Difference

Winner-loser effects influence subsequent agonistic interactions between conspecifics. Previous winning experiences could strengthen future aggression and increase the chance of winning the next agonistic interaction, while previous losing experiences could have the opposite effect. Although the role of A-to-I RNA editing has been recently implicated in chronic social defeat stress and aggressive behavior, it remains to be further elucidated in chronic social conflicts in agonistic interactions, especially in the repeated aggression (winners) and repeated defeat (losers) resulted from these conflicts. In the current study, transcriptome-wide A-to-I RNA editing in the dorsal striatum was investigated in a mouse model of chronic social conflicts, and compared between mice repeatedly winning and losing daily agonistic interactions. Our analysis identified 622 A-to-I RNA editing sites in the mouse dorsal striatum, with 23 to be differentially edited in 22 genes, most of which had been previously associated with neurological, psychiatric, or immune disorders. Among these differential RNA editing (DRE) sites four missense variants were observed in neuroligin 2 (Nlgn2), Cdc42 guanine nucleotide exchange factor 9 (Arhgef9) BLCAP apoptosis inducing factor (Blcap), and cytoplasmic FMR1 interacting protein 2 (Cyfip2), as well as two noncoding RNA sites in small nucleolar RNA host gene 11 (Snhg11) and the maternally expressed 3 (Meg3) gene. Moreover, significant changes were observed in gene functions and pathways enriched by genes with A-to-I RNA editing in losers and especially winners compared to controls. Our results demonstrate that repeated winning and losing experiences in chronic social conflicts are linked to A-to-I RNA editing pattern difference, underlining its role in the molecular mechanism of agonistic interactions between conspecifics.

Cytotoxic T-Cell Trafficking Chemokine Profiles Correlate With Defined Mucosal Microbial Communities in Colorectal Cancer

The involvement of gut microbiota in T-cell trafficking into tumor tissue of colorectal cancer (CRC) remains to be further elucidated. The current study aimed to evaluate the expression of major cytotoxic T-cell trafficking chemokines (CTTCs) and chemokine-associated microbiota profiles in both tumor and adjacent normal tissues during CRC progression. We analyzed the expression of chemokine C-X-C motif ligands 9, 10, and 11 (CXCL9, CXCL10, and CXCL11), and C-C motif ligand 5 (CCL5), characterized gut mucosa-associated microbiota (MAM), and investigated their correlations in CRC patients. Our results showed that the expression of CXCL9, CXCL10, and CXCL11 was significantly higher in tumor than in adjacent normal tissues in 136 CRC patients. Notably, the high expression of CXCL9 in tumor tissues was associated with enhanced CD8⁺ T-cell infiltration and improved survival. Moreover, the MAM in tumor tissues showed reduction of microbial diversity and increase of oral bacteria. Microbial network analysis identified differences in microbial composition and structure between tumor and adjacent normal tissues. In addition, stronger associations between oral bacteria and other gut microbes were observed. Furthermore, the correlation analysis between the defined MAM and individual CTTCs showed that the CTTCs' correlated operational taxonomic units (OTUs) in tumor and adjacent normal tissues rarely overlap with each other. Notably, all the enriched OTUs were positively correlated with the CTTCs in either tumor or adjacent normal tissues. Our findings demonstrated stronger interactions between oral bacteria and gut microbes, and a shifted correlation pattern between MAM and major CTTCs in tumor tissues, underlining possible mechanisms of gut microbiota-host interaction in CRC.

Transcriptome-Wide Identification of G-to-A RNA Editing in Chronic Social Defeat Stress Mouse Models

Emerging evidence suggests that RNA editing is associated with stress, neurological diseases, and psychiatric disorders. However, the role of G-to-A RNA editing in chronic social defeat stress (CSDS) remains unclear. We herein identified G-to-A RNA editing and its changes in the ventral tegmental area (VTA), a key region of the brain reward system, in CSDS mouse models under emotional stress (ES) and physiological stress (PS) conditions. Our results revealed 3812 high-confidence G-to-A editing events. Among them, 56 events were significantly downregulated while 23 significantly upregulated in CSDS compared to controls. Moreover, divergent editing patterns were observed between CSDS mice under ES and PS conditions, with 42 and 21 events significantly upregulated in PS and ES, respectively. Interestingly, differential RNA editing was enriched in genes with multiple editing events. Genes differentially edited in CSDS included those genetically associated with mental or neurodevelopmental disorders, especially mood disorders, such as FAT atypical cadherin 1 and solute carrier family 6 member 1. Notably, changes of G-to-A RNA editing were also implicated in ionotropic glutamate receptors, a group of well-known targets of adenosine-to-inosine RNA editing. Such results demonstrate dynamic G-to-A RNA editing changes in the brain of CSDS mouse models, underlining its role as a potential molecular mechanism of CSDS and stress-related diseases.

A novel missense mutation of RPGR identified from retinitis pigmentosa affects splicing of the ORF15 region and causes loss of transcript heterogeneity

Mutations in the retinitis pigmentosa GTPase regulator (RPGR) gene, are the major cause of X-linked retinitis pigmentosa (RP), in which exon open reading frame 15 (ORF15) of RPGR has been implicated to play a substantial role. We identified a novel hemizygous missense mutation E585K of RPGR from whole-exome sequencing of RP. RNA-Seq analysis and functional study were conducted to investigate the underlying pathogenic mechanism of the mutation. Our results showed that the mutation actually affected RPGR ORF15 splicing. RNA-Seq analysis of the human retina followed by validation in cells revealed a complex splicing pattern near the 3' boundary of RPGR exon 14 in the ORF15 region, resulting from a variety of alternative splicing events (ASEs). The wildtype RPGR mini-gene expressed in human 293T cells confirmed these ASEs in vitro. In contrast, without new RNA species detected, the mutant mini-gene disrupted the splicing pattern of the ORF15 region, and caused loss of RPGR transcript heterogeneity. The RNA species derived from the mutant mini-gene were predominated by a minor out-of-frame transcript that was also observed in wildtype RPGR, resulting from an upstream alternative 5' splice site in exon 14. Our findings therefore provide insights into the influence of RPGR exonic mutations on alternative splicing of the ORF15 region, and the underlying molecular mechanism of RP.

The impact of omega-3 fatty acid supplementation on glycemic control in patients with gestational diabetes: a systematic review and meta-analysis of randomized controlled studies

Background: Omega-3 fatty acid supplementation shows some treatment efficacy for gestational diabetes. This systematic review and meta-analysis is conducted to investigate the efficacy of omega-3 fatty acid supplementation for glycemic control in patients with gestational diabetes.Methods: The databases including PubMed, Embase, Web of science, EBSCO, and Cochrane Library databases are systematically searched for collecting the randomized controlled trials (RCTs) regarding the efficacy of omega-3 fatty acid versus placebo for gestational diabetes.Results: This meta-analysis has included seven RCTs. Compared with placebo group in patients with gestational diabetes, omega-3 fatty acids supplementation results in remarkably reduced fasting plasma glucose (FPG) (standard mean difference (std. MD) = -0.56; 95% confidence interval (CI) = -0.87 to -0.24; p = .0005), homeostatic model of assessment for insulin resistance (HOMA-IR) (std. MD = -0.52; 95% CI = -0.83 to -0.21; p = .001), but has no statistical impact on macrosomia (risk ratio (RR) = 0.48; 95% CI = 0.22-1.02; p = .06), newborns' hyperbilirubinemia (RR = 0.46; 95% CI = 0.19-1.10; p = .08), nitric oxide (NO) (std. MD = 0.17; 95% CI = -0.64-0.98; p = .68), preterm delivery (RR = 1.75; 95% CI = 0.08-3.80; p=.16) and preeclampsia (RR =0.74; 95% CI = 0.26-2.16; p = .59). However, notably decreased high sensitivity C-reactive protein (hs-CRP) is revealed after omega-3 fatty acids supplementation (std. MD = -1.14; 95% CI = -2.0 to -0.29; p = .009).Conclusions: Omega-3 fatty acids supplementation can provide substantially beneficial effects on glycemic control and inflammatory response for gestational diabetes.

Burkholderia pseudomallei survival in lung epithelial cells benefits from miRNA-mediated suppression of ATG10

Burkholderia pseudomallei is the causative agent of melioidosis, a disease with high mortality, which is prevalent in tropical regions of the world. A recent study shows that B. pseudomallei can survive inside mammalian cells because of its ability to actively evade cell autophagy. However, the underlying mechanisms remain unclear. In the present study, based on microarray screening, we found that ATG10 was downregulated following B. pseudomallei infection in A549 human lung epithelial cells. Forced expression of ATG10 accelerated the elimination of intracellular B. pseudomallei by enhancing the process of autophagy. Moreover, MIR4458, MIR4667-5p, and MIR4668-5p were found, by microarray screening, to be upregulated in response to B. pseudomallei infection. These 3 novel miRNAs, MIR4458, MIR4667-5p, and MIR4668-5p, targeted to the 3'-untranslated region of ATG10 in different time-course and spatial manners. Upregulation of these miRNAs reduced the level of ATG10 and inhibited autophagy, leading to increasing survival rate of intracellular B. pseudomallei. Furthermore, the increase of these miRNAs was correlated with the reduced promoter methylation status in A549 cells in response to B. pseudomallei infection. Our results reveal that 3 novel miRNAs regulate autophagy-mediated elimination of B. pseudomallei by targeting ATG10, and provide potential targets for clinical treatment.

Molecular cloning, sequence identification, and gene expression analysis of bovine ADCY2 gene

Adenylyl cyclase 2 (ADCY2), a class B member of adenylyl cyclases, is important in accelerating phosphor-acidification as well as glycogen synthesis and breakdown. Given its distinct role in flesh tenderization after butchering, we cloned and sequenced the ADCY2 gene from Yanbian cattle and assessed its expression in bovine tissues. A 2947 bp nucleotide sequence representing the full-length cDNA of bovine ADCY2 gene was obtained by 5' and 3' remote analysis computations for gene expression. Analyses of the putative protein sequence showed that ADCY2 had high homology among species, except with the non-mammal Oreochromis niloticus. Gene structural domain analyses in humans and rats indicated that the ADCY2 protein had no flaw; only the transmembrane domain was reduced and the CYCc structure domain was shortened. Assessment of ADCY2 expression in bovine tissues by real-time PCR showed that the highest expression was in the testes, followed by the longissimus dorsi, tensor fasciae latae, and latissimus dorsi. These data will serve as a foundation for further insight into the cattle ADCY2 gene.

Axillary lymph node status, adjusted for pathologic complete response in breast and axilla after neoadjuvant chemotherapy, predicts differential disease-free survival in breast cancer

BACKGROUND

Our retrospective study in breast cancer patients evaluated whether integrating subtype and pathologic complete response (pcr) information into axillary lymph node restaging after neoadjuvant chemotherapy (nac) adds significance to its prognostic values.

METHODS

Patients included in the analysis had stage ii or iii disease, with post-nac axillary lymph node dissection (alnd), without sentinel lymph node biopsy before completion of nac, with definitive subtyping data and subtype-oriented adjuvant treatments. The ypN grading system was used to restage axillary lymph node status, and ypN0 was adjusted by pcr in both breast and axilla into ypN0(pcr) and ypN0(non-pcr). Univariate and multivariate survival analyses were performed.

RESULTS

Among the 301 patients analyzed, 145 had tumours that were hormone receptor-positive (hr+) and negative for the human epidermal growth factor receptor (her2-), 101 had tumours that were positive for her2 (her2+), and 55 had tumours that were triple-negative. The rate of pcr in both breast and axilla was 11.7%, 43.6%, and 25.5% respectively for the 3 subtypes. Compared with the non-pcr patients, the pcr patients had better disease-free survival (dfs) and overall survival (os): p = 0.002 for dfs and p = 0.011 for os. In non-pcr patients, dfs and os were similar in the ypN0(non-pcr) and ypN1 subgroups, and in the ypN2 and ypN3 subgroups. We therefore grouped the ypN grading results into ypN0(pcr) (n = 75), ypN0- 1(non-pcr) (n = 175), and ypN2-3 (n = 51). In those groups, the 3-year dfs was 98%, 91%, and 56%, and the 3-year os was 100%, 91%, and 82% respectively. The differences in dfs and os between those three subgroups were significant (all p < 0.05 in paired comparisons). Multivariate Cox regression showed that subtype and ypN staging adjusted by pcr were the only two independent factors predicting dfs.

CONCLUSIONS

Axillary lymph node status after nac, adjusted for pcr in breast and axilla, predicts differential dfs in patients without prior sentinel lymph node biopsy.

[Distribution, flux and photoproduction of carbon monoxide in the Yellow Sea and the Bohai Sea in spring]

Concentration distribution, sea-to-air flux, photoproduction of carbon monoxide (CO) in the surface seawater and atmospheric CO mixing ratio were measured in the Yellow Sea and the Bohai Sea. A headspace analysis system was used for CO measurement. The concentrations of CO in the surface seawater ranged from 0.19 to 3.57 nmol x L(-1), with an average of 1.24 nmol x L(-1) ( SD = 0.79, n = 69). Overall, the concentrations of CO displayed a decreasing trend from the coast to the offshore stations and followed diurnal variations after classifying and averaging the CO concentrations according to sampling and analysing time in the unit of one hour, with the maximum values in midnoon which was 10 folds higher than the minimum values in predawn. Atmospheric CO mixing ratios varied from 215 x 10(-9) to 850 x 10(-9), with an average of 414 x 10(-9) (SD = 140 x 10(-9), n = 69), due to obvious terrestrial input. The supersaturation factors of CO varied from 0.42-18.90, with an average of 3.61 (SD = 2.99, n = 69), indicating that the Yellow Sea and the Bohai Sea was a net source of atmospheric CO. The average sea-to-air fluxes of CO from the Yellow Sea and the Bohai Sea were estimated to be (1.22 +/- 1.70) micromol x (m2 x d)(-1) by the LM86 equation and (2.13 +/- 2.91) micromol x (m2 x d)(-1) by the W92 equation, respectively. Using SMARTS2 spectral irradiance model to estimate CO production, the photoproduction rate of CO was 54.60 micromol x (m2 x d)(-1) and the photoproduction of carbon in the Yellow Sea and the Bohai Sea was 26.95 x 10(9) g in spring. The photoproduction rate of CO was 25-50 times higher than the sea-to-air flux, suggesting that most part of CO was removed by microbial process in the surface seawater.

4-{(E)-N′-[2-(8-Quinolyloxy)acetyl]hydrazonomethyl}benzoic acid methanol solvate

In the title compound, C₁₉H₁₅N₃O₄·CH₄O, the mean planes of the benzene ring and the quinoline system make a dihedral angle of 6.7 (2)°. The acetohydrazide host mol­ecules are connected via inter­molecular O—H⋯O hydrogen bonds into two-dimensional zigzag sheets extending in the ab plane. The methanol solvent mol­ecule is linked to the host mol­ecule via inter­molecular N—H⋯O and O—H⋯N hydrogen bonds.

(E)-N′-(4-Nitrobenzylidene)-2-(8-quinolyloxy)acetohydrazide methanol solvate

In the title compound, C₁₈H₁₄N₄O₄·CH₃OH, the mean planes of the benzene ring and the quinoline ring system make a dihedral angle of 15.5 (2)°. The methanol solvent mol­ecule forms an O—H⋯N hydrogen bond to the quinoline ring system and accepts an N—H⋯O hydrogen bond from the hydrazide NH group. The mol­ecules lie in layers approximately parallel to (101) and C—H⋯O inter­actions exist between mol­ecules within the layers.

(E)-6-Chloro-N'-(3,5-dichloro-2-hydroxy-benzyl-idene)-nicotinohydrazide

The title Schiff base compound, C₁₃H₈Cl₃N₃O₂, was synthesized by the condensation reaction of 3,5-dichloro­salicyl­aldehyde with 6-chloro­nicotinic acid hydrazide in 95% ethanol. The mol­ecule is nearly planar, with a dihedral angle of 1.9 (2)° between the aromatic ring planes, and an intra­molecular O—H⋯N hydrogen bond is observed. In the crystal, the mol­ecules are connected by inter­molecular N—H⋯O hydrogen bonds into infinite chains propagating in [100].

Transcription factor GATA-5 selectively up-regulates mucin gene expression

PURPOSE

Overlapping expression patterns of epithelial mucins, MUC1-MUC6, and transcription factor GATA-5 were reported previously. However, the functional relationship between them is poorly understood. The aim of the current study is to elucidate whether or not expression of mucin genes is regulated by GATA-5.

METHODS

GATA-5 was transiently overexpressed in COS-7 and 293T cells by plasmid transfection and/or adenovirus infection. GATA-5 expression was confirmed by Western blot analysis. Expression of mucin genes was studied by reverse-transcription-PCR. Reporter gene assays were employed to analyze the effect of GATA-5 on the promoter activity of mucin genes.

RESULTS

mRNA levels of MUC2, MUC3, and MUC4 were increased, whereas those of MUC1, MUC5AC, MUC5B, and MUC6 remained unchanged upon the overexpression of GATA-5 in both COS-7 and 293T cells. By means of luciferase assay, GATA-5 was found to activate the promoters of the human MUC2 and MUC4 genes. GATA-5 lacking the zinc finger domain impaired these functions.

CONCLUSIONS

These findings indicate that GATA-5 may play important roles in the regulation of mucin expression and gastrointestinal epithelial cell differentiation.

GATA-4 and GATA-5 transcription factor genes and potential downstream antitumor target genes are epigenetically silenced in colorectal and gastric cancer

The GATA family of transcription factors participates in gastrointestinal (GI) development. Increases in GATA-4 and -5 expression occur in differentiation and GATA-6 expression in proliferation in embryonic and adult settings. We now show that in colorectal cancer (CRC) and gastric cancer promoter hypermethylation and transcriptional silencing are frequent for GATA-4 and -5 but are never seen for GATA-6. Potential antitumor target genes upregulated by GATA-4 and -5, the trefoil factors, inhibinalpha, and disabled-2 (Dab2) are also silenced, in GI cancers, with associated methylation of the promoters. Drug or genetically induced demethylation simultaneously leads to expression, in CRC cells, of all of the GATA-4, -5, and downstream genes. Expression of exogenous GATA-5 overrides methylation at the downstream promoters to activate the target genes. Selection for silencing of both upstream transcription factors and their target genes in GI cancers could indicate that epigenetic silencing of the involved genes provides a summated contribution to tumor progression.

The dynamic change of plasma endothelin-1 during the perioperative period in patients with rheumatic valvular disease and secondary pulmonary hypertension

The arterial plasma endothelin-1 concentration was substantially more elevated in 15 patients with rheumatic valvular disease and secondary pulmonary hypertension than in healthy volunteers (3.66 +/- 2.20 versus 1.17 +/- 0.38 pg/ml, mean +/- standard deviation; p < 0.01). The preoperative plasma endothelin-1 level was highly correlated with the pulmonary hemodynamics: pulmonary artery systolic pressure (r = 0.94, p < 0.001), pulmonary artery mean pressure (r = 0.86, p < 0.001), pulmonary capillary wedge pressure (r = 0.82, p < 0.001), and pulmonary vascular resistance (r = 0.63, p < 0.02). After valve replacement, the plasma endothelin-1 concentration declined substantially and the pulmonary hemodynamics improved markedly. Two weeks after the operation, the plasma endothelin-1 level in patients (1.26 +/- 0.45 pg/ml, mean +/- standard deviation) was not statistically different from that in the healthy volunteers. The plasma endothelin-1 concentration continuously increased during the course of cardiopulmonary bypass and peaked after cessation of bypass. The peak plasma endothelin-1 level (13.49 +/- 4.60 pg/ml, mean +/- standard deviation) positively correlated with the bypass time (r = 0.64, p < 0.02) and negatively correlated with the urine volume during bypass (r = -0.69, p < 0.01). We conclude that (1) increased plasma endothelin-1 might be implicated in the pathogenesis of secondary pulmonary hypertension caused by rheumatic valvular disease and (2) markedly elevated plasma endothelin-1 concentrations might be associated with the mechanism of cardiac or renal dysfunction after prolonged cardiopulmonary bypass.

[Long-term results of bioprosthetic valves mounted on flexible stent]

From April, 1984 to April, 1989, 104 heart valve replacements were performed in 103 patients. The atrio-ventricular valves (97 mitral and 7 tricuspid valves) were replace by bioprosthetic valves mounted on the flexible stent made of Elgiloy. They included 91 porcine aortic valves and 13 bovine pericardial valves. Only 74 patients recovered and discharged from the hospital because of high operative mortality of re-replacement and double valve replacement (19 and 30 patients, respectively). These patients were followed-up for 8 to 68 months with a total follow-up period of 297 patient-years. Two patients developed cerebral embolism and two developed bacterial endocarditis. The incidence of the two complications was 0.67%/patient-year. No valve failure occurred. Long-term results of bioprosthetic heart valves mounted on flexible stent were better than those mounted on rigid stent.

[Bronchial carcinoid. A clinical, roentgenological and pathological study of 17 cases]

17 cases with bronchial carcinoid were reported. 16 cases of them were proved pathologically after pulmonary resection, and the remaining one was confirmed histopathologically through bronchoscopic biopsy. 64.7% was under 40 years of age. The main clinical manifestations were cough, hemoptysis, fever and repeated pneumonitis. In one patient, the carcinoid was associated with Cushing's syndrome. Chest roentgenograms showed lesions centrally located in 12 cases, and peripherally located in 5 cases. Histological examination revealed 15 typical and 2 atypical carcinoid tumors. This disease was usually misdiagnosed as lung cancer, tuberculoma and benign tumors. Chest X-ray examination and fiberoptic bronchoscopic biopsy are helpful to the diagnosis of the disease. Pulmonary resection was performed in 16 cases. Two patients had hilar lymph node metastases, one of them had also involvement of pericardium. There was no operative mortality. In the follow-up study, the disease-free actuarial survival following pulmonary resection was 92.9% at 5 years. 2 patients died. One died of respiratory failure 4 months after pneumonectomy, the other died of pericardium involvement of carcinoid 8 months after operation. Resection is the only effective treatment for bronchial carcinoid.

[Diagnosis and treatment of multiple primary bronchogenic carcinoma]

From 1974 to 1983, 4 patients with multiple primary bronchogenic carcinoma were treated. It comprised 0.64% (4/622) of all lung cancers admitted to our hospital during the same period. Out of these 4 patients, 2 were synchronous and 2 were metachronous. 3 were bilateral, the other was unilateral. 3 were preoperatively misdiagnosed as pulmonary metastases and the fourth case was confirmed only postoperatively. The common pathologic combination was squamous carcinoma and squamous carcinoma. Two patients with synchronous cancers survived for 15 and 42 months after the operation. Two with metachronous cancers are living up to now (for more than four years) after the second cancer had been removed. The diagnosis and treatment of this cancer are discussed. The authors believe that the survival rate may be increased by early diagnosis and prompt operation.