De novo DNA methylation of the paternal genome in 2-cell mouse embryos.

The developmental dynamics of DNA methylation events have been well studied. Active demethylation of the paternal genome occurs in the zygote, passive demethylation occurs during cleavage stages, and de novo methylation occurs by the blastocyst stage. It is believed that the paternal genome has lower levels of methylation during early development than the maternal genome. However, in this study, we provide direct and indirect evidence of genome-wide de novo DNA methylation of the paternal genome after the first cell cycle in mouse embryos. Although very little methylation was detected within the male pronucleus in zygotes, an intense methylation signal was clearly visible within the androgenetic 2-cell embryos. Moreover, the DNA methylation level of the paternal genome in the post-zygotic metaphase embryos was similar to that of the maternal genome. Using indirect immunofluorescence with an antibody to methylated lysine 9 in histone H3, we provided new evidence to support the concept of spatial compartmentalization of parental genomes in 2-cell mouse embryos. Nevertheless, the transient segregation of parental genomes was not observed by determining the DNA methylation distribution in the 2-cell embryos even though DNA methylation asymmetry between the maternal and paternal pronucleus existed in the 1-cell stage. The disappearance of separate immunofluorescence signals of 5-methyl cytosine in the 2-cell embryos might be attributed to the de novo methylation of the paternal genome during the first mitotic cycle.

Nizatidine improves clinical symptoms and gastric emptying in patients with functional dyspepsia accompanied by impaired gastric emptying.

BACKGROUND/AIMS: In this crossover study, we investigated whether nizatidine, a H(2)-receptor antagonist, can alleviate clinical symptoms and gastric emptying in patients with Rome III-based functional dyspepsia (FD) with or without impaired gastric emptying. METHODS: We enrolled 30 patients presenting with FD symptoms (epigastric pain syndrome, n = 6; postprandial distress syndrome, n = 24). Rome III-based FD patients were treated with nizatidine (300 mg/day) or placebo for 4 weeks in a crossover trial. Gastric motility was mainly evaluated with the T(max) value using the (13)C-acetate breath test. Meal-related symptoms were defined as postprandial fullness and early satiation. Gastroesophageal symptom was defined as a burning feeling rising from the stomach or lower chest up toward the neck. Acylated- and desacylated ghrelin levels were evaluated by the ELISA method. Clinical symptoms, gastric emptying and ghrelin levels were evaluated at three different points during the study (pretreatment, after 4 weeks former treatment and after 4 weeks later treatment). The primary end point of this study was to determine whether nizatidine would improve clinical symptoms and gastric emptying in FD patients with or without impaired gastric emptying via affecting ghrelin levels. RESULTS: Meal-related symptoms of the patients treated with nizatidine improved significantly (21/30; 70%) compared to those treated with placebo (3/30; 10%). In addition, nizatidine treatment also significantly improved gastroesophageal symptoms (16/30; 53%) compared to those treated with placebo (0/30; 0%). Nizatidine treatment in patients with FD accompanied by impaired gastric emptying significantly improved clinical symptoms and T(max) value as a marker of gastric emptying (10/11, 91%; 9/11, 82%) compared to placebo therapy, respectively. There were no significant differences in ghrelin levels between nizatidine treatment and placebo therapy. CONCLUSION: Nizatidine administration significantly improved both gastric emptying and clinical symptoms in FD patients with impaired gastric emptying.

Continuing perioperative estrogen therapy does not increase venous thromboembolic events in transgender patients: a systematic review and meta-analysis.

OBJECTIVE: The aim of this study is to compare the risk of venous thromboembolic events (VTE) between patients suspending and continuing estrogen therapy perioperatively, in male to female gender-affirming surgery (vaginoplasty). MATERIALS AND METHODS: The authors conducted a systematic review and meta-analysis of existing research on male to female gender-affirming study, which compared the risk of VTE among the usage of estrogen perioperatively. RESULTS: A total of 209 studies were identified as potentially eligible among PubMed, Embase, and Cochrane library databases. Among the studies, 191 studies were excluded due to their abstract inappropriateness. Out of the remaining 18 studies, only 3 articles were eligible and were finally included. Meta-analysis was performed and showed odds ratio of 0.77 (95% CI: 0.04, 14.01). CONCLUSIONS: Perioperative estrogen therapy does not increase VTE risk on male to female gender-affirming surgery. Therefore, estrogen therapy may be continued perioperatively in vaginoplasty. More prospective studies are needed.

COVID-19 susceptibility and clinical outcomes in autoimmune inflammatory rheumatic diseases (AIRDs): a systematic review and meta-analysis.

OBJECTIVE: This meta-analysis aims to assess the susceptibility to and clinical outcomes of COVID-19 in autoimmune inflammatory rheumatic disease (AIRD) and following AIRD drug use. MATERIALS AND METHODS: We included observational and case-controlled studies assessing susceptibility and clinical outcomes of COVID-19 in patients with AIRD as well as the clinical outcomes of COVID-19 with or without use of steroids and conventional synthetic disease-modifying antirheumatic drugs (csDMARDs). RESULTS: Meta-analysis including three studies showed that patients with AIRD are not more susceptible to COVID-19 compared to patients without AIRD or the general population (OR: 1.11, 95% CI: 0.58 to 2.14). Incidence of severe outcomes of COVID-19 (OR: 1.34, 95% CI: 0.76 to 2.35) and COVID-19 related death (OR: 1.21, 95% CI: 0.68 to 2.16) also did not show significant difference. The clinical outcomes of COVID-19 among AIRD patients with and without csDMARD or steroid showed that both use of steroid (OR: 1.69, 95% CI: 0.96 to 2.98) or csDMARD (OR: 1.35, 95% CI: 0.63 to 3.08) had no effect on clinical outcomes of COVID-19. CONCLUSIONS: AIRD does not increase susceptibility to COVID-19, not affecting the clinical outcome of COVID-19. Similarly, the use of steroids or csDMARDs for AIRD does not worsen the clinical outcome.

The kinetics of photocatalytic degradation of aliphatic carboxylic acids in an UV/TiO2 suspension system.

Kinetic studies on the photocatalytic degradation of aliphatic carboxylic acids were carried out in a slurry photoreactor with in-situ monitoring, employing artificial UV light as the source of energy and nano-TiO2 powder as the catalyst. The influences on the photocatalytic degradation such as the initial concentration of reactant (C0), catalyst dosage (CTiO2), UV intensity (Ia) and pH value have been investigated. Good agreement has been obtained between the value calculated by Langmuir-Freundlich-Hinshelwood (L-F-H) model and experimental data, with coefficient of multiple determination (R2) varying from 0.880 to 0.999. The L-F-H model has been proven to be feasible in describing the kinetic characteristic of the photocatalytic degradation of aliphatic carboxylic acids. Moreover, the apparent reaction rate constant (k) of the photocatalytic degradation of dicarboxylic acids is higher than that of monocarboxylic acids with the same carbon atoms. This shows that the photocatalytic degradation rate is favoured by different chemical structure.

Periodontal Pathogens Modulate Lipid Flux via Fatty Acid Binding Protein 4.

A strong correlation between chronic periodontitis and systemic diseases (e.g., cardiovascular disease, metabolic disorders) has been suggested for several decades. However, the evidence supporting this correlation is restricted primarily to epidemiologic studies, with only a few experimental outcomes confirming such a correlation and providing information about the underlying molecular mechanisms. To reveal a correlation between periodontitis and systemic diseases as well as a relevant molecular pathway, we investigated the effects of Porphyromonas gingivalis and Fusobacterium nucleatum, which play roles in chronic periodontitis progression, on Raw264.7 and THP-1 macrophages. Infection with P. gingivalis or F. nucleatum significantly induced the expression of fatty acid binding protein 4 (FABP4), one of the most important adipokines that play a role in the progression of systemic diseases such as atherosclerosis and type 2 diabetes. Periodontal pathogen-induced FABP4 expression in macrophages promoted lipid uptake by these cells, as demonstrated by the diminished lipid accumulation in cells treated with an FABP4 inhibitor, BMS309403, or with knockdown of FABP4 expression. This periodontal pathogen-induced FABP4 expression was dependent on the JNK pathway, and JNK inhibition reduced lipid uptake by reducing FABP4 expression. Serum levels of antibodies against P. gingivalis correlated with serum FABP4 levels in humans, whereas no association occurred between F. nucleatum antibody titers and FABP4 levels. To our knowledge, this report is the first to experimentally demonstrate that periodontal pathogens stimulate lipid uptake in macrophages by modulating FABP4 expression. These findings strongly support the hypothesis that periodontitis may affect the progression of various systemic diseases.

Elongation factor EF-1 alpha gene dosage alters translational fidelity in Saccharomyces cerevisiae.

Changes in the dosage of genes encoding elongation factor EF-1 alpha were shown to cause parallel changes in the misreading of nonsense codons. Higher amounts of EF-1 alpha were correlated with increased nonsense suppression, suggesting that the level of EF-1 alpha is critically involved in translational fidelity.

Quality of life outcomes following laparoscopic total mesorectal excision for low rectal cancers: a clinical control study.

AIMS: To evaluate the health-related quality of life (HRQoL) outcomes in patients undergoing laparoscopic total mesorectal excision (LTME) with anal sphincter preservation (ASP) for low rectal cancers. METHODS: Patients undergoing LTME with ASP or open procedures (OTME) for low rectal cancers were prospectively followed up. All patients were treated in curative attempt and were free of local recurrence during the study. HRQoL was assessed by questionnaires during 3-6 months, 12-18 months, and 2-5 years after surgery. RESULTS: From June 2001 to March 2006, 125 patients undergoing LTME and 103 undergoing OTME were included in this study. In contrast to OTME patients, the LTME ones showed significantly better physical function during 3-6 months after surgery, less micturition problems within 12-18 months, less male sexual problems and better sexual function during 12-18 months after surgery, with better sexual enjoyment after 24 months postoperatively. Both groups showed significant improvement in most subscales from the first to the second assessment, and an improvement in sexual enjoyment from the second to the third assessment. The sexual function, micturition problems and male sexual problems in the LTME group significantly improved from the first to the second assessment, whereas the sexual function in the OTME group improved from the second to the third assessment. CONCLUSIONS: Patients undergoing LTME for low rectal cancers can achieve superior postoperative HRQoL than patients undergoing OTME, with superior physical function, micturition function, overall sexual and male sexual functions in the short term, and better sexual enjoyment in the long term. The HRQoL of both LTME and OTME patients may be expected to improve over time, particularly over the first postoperative year.

Microsatellite instability-associated mutations associate preferentially with the intestinal type of primary gastric carcinomas in a high-risk population.

Most colon cancers exhibiting microsatellite instability (MI), a mutator phenotype of mismatch repair failure, are associated with mutations of the transforming growth factor-beta receptor type II genes (TGF-beta RII). Of intestinal- and diffuse-type gastric carcinomas, the former have been thought to arise from intestinal metaplasia in which gastric mucosa resembles intestinal mucosa. To evaluate the preferential histological type of MI-associated mutations in the development of gastric carcinoma, mutations of TGF-beta RII, p53, and p16 were analyzed for the two types of primary gastric carcinomas showing MI. Of 50 primary gastric carcinomas, including 33 intestinal types and 17 diffuse types, 15 cases (30%) demonstrated MI at 1 or more of the 11 microsatellite markers tested. The 15 MI cases were classified into two groups, widespread MI and low-level MI, based on the number of markers exhibiting the instability. Eleven were widespread MIs, and the remaining four cases were low-level MIs. Ten of the 11 (91%) widespread MIs were of the intestinal type, and 1 case (9%) was of the diffuse type. Of the 11 widespread MIs, 10 cases (91%) demonstrated frameshift mutations within the polyadenylate tract of the TGF-beta RII. The frameshift mutation was rarely detected at p53 and p16 (1 of 11, 9%). In contrast, the four low-level MI cases had no frameshift mutations within the repeat sequences of TGF-beta RII, p53, and p16, but two of the four cases demonstrated base substitution mutations within p53. Our results suggest that mismatch repair failure can mutate the TGF-beta RII and may provide one of the pathways for the development of the intestinal-type gastric carcinoma in high-risk populations.

Morphological Study of Poly(vinylbenzyl chloride)-Grafted Poly(ethylene-co-tetrafluoroethylene) [ETFE-g-PVBC] Films Using Small-Angle Neutron Scattering Analysis.

In this study, the effect of degree of the grafting and crosslinking on the morphology of the crystalline domain in poly(vinylbenzyl chloride)-grafted poly(ethylene-co-tetrafluoroethylene) [ETFE-g-PVBC] films was investigated using a SANS (small-angle neutron scattering) analysis. The grafted films can be used as a precursor for ion-exchange membrane. ETFE-g-PVBC films with various degrees of cross-linking were prepared by a simultaneous irradiation grafting of vinylbenzyl chloride (VBC) and divinylbenzene (DVB) onto an ETFE film. The SEM-EDX (scanning electron microscopy-energy dispersive X-ray spectroscopy) results of a cross-sectional distribution of ETFE-g-PVBC films showed that the chlorine atoms were well-distributed throughout the films. SANS profiles of the PVBC-grafted films in the absence of a DVB crosslinker showed that the crystalline domain peaks were observed and the peak maximum position shifted significantly from 0.032 Å-(-1) to 0.02 Å(-1) with an increase in the degree of grafting. However, peak maximum positions of the PVBC-grafted films in the presence of a DVB crosslinker shifted slightly from 0.02 Å(-1) to 0.024 Å(-1) with an increase in the amount of DVB monomer at same degree of grafting. These results indicate that the degree of grafting and crosslinking affect the morphology of the crystalline domain in the ETFE-g-PVBC films.

Evidence of genetic progression in human gastric carcinomas with microsatellite instability.

Mutator phenotype tumors provide unique opportunities to unravel malignant progression because of various gene alterations acquired during clonal tumor evolution. Gastric carcinomas, which have been known to show frequent genetic instability, would be composed of initial gene alterations shared by most tumor areas and subsequent alterations restricted to particular tumor sites. To analyse the timing of genetic events, we examined separate sites of tumor tissue obtained from a given gastric carcinoma patient with microsatellite instability (MSI). Our study included 95 normal/tumor area pairs from 25 patients. Six of the 25 patients (24%) demonstrated various levels of MSI ranging from 7% (two of 30) to 97% (28 of 29) of markers tested in multiple tumor sites. Of the six patients, five manifested frameshift mutations in a tract of ten deoxyadenosines within transforming growth factor beta receptor type II and four demonstrated frameshift mutations in a tract of eight deoxyguanosines within BAX. These mutations were common to all tumor sites regardless of the various level of MSI phenotype, indicating initial events. Two of the six patients exhibited frameshift mutations in mononucleotide repeats of mismatch repair genes, hMSH3 and hMSH6, and the insulin-like growth factor II receptor in restricted tumor areas, indicating additional alterations. Insulin-like growth factor II receptor mutations appear to be caused by hMSH3 and hMSH6 mutations because the former mutations were confined to tumor portions with the latter two mismatch repair lesions. These results provide genetic progression evidence for gastric carcinomas of the mutator pathway. In this pathway, mismatch repair insufficiency initially targets mononucleotide tracts of transforming growth factor beta receptor type II and BAX. During tumorigenesis, primary mismatch repair failure may give rise to the secondary mismatch repair lesions, frameshift mutations of hMSH3 and hMSH6, which result in another tumorigenic mutation in the insulin-like growth factor II receptor.

Allosuppressors that enhance the efficiency of omnipotent suppressors in Saccharomyces cerevisiae.

Two recessive Mendelian-allosuppressors have been isolated and have been shown to enhance the efficiency of omnipotent suppressors thought to be translational ambiguity mutations. These allosuppressors are unlinked to each other or to the omnipotent suppressors on which they act. They also increase the efficiency of the serine-inserting UAA-suppressor, SUP16. One allosuppressor is allelic or tightly linked to the previously isolated sal2. Another allosuppressor, called sal6, represents a new locus, unlinked to the previously isolated sal1-sal5 that enhance the efficiency of the UAA-suppressors. When present singly in the absence of suppressors or other modifiers the sal2 and sal6 mutations do not have suppressor activity. However, when sal2 and sal6 are combined together in a haploid cell they do suppress weakly. In addition sal2 becomes a weak suppressor in the presence of the [eta +] modifying factor.

The N-terminal, dehydrogenase/cyclohydrolase domain of yeast cytoplasmic trifunctional C1-tetrahydrofolate synthase requires the C-terminal, synthetase domain for the catalytic activity in vitro.

The yeast ADE3(1-333) gene which encodes a truncated protein containing the N-terminal 5,10-methylene-tetrahydrofolate (THF) dehydrogenase (D)/5,10-methyl-THF cyclohydrolase (C) domain of cytoplasmic trifunctional C1-THF synthase is able to complement all the phenotypes associated with ade3 mutations in vivo. However, expression of the ADE3(1-333) gene in an ade3 strain does not retain any D activity in vitro. Expression in a yeast ade3 strain of the ADE3(1-333) fused to the Escherichia coli lacZ gene or to the yeast SER2 gene allows detection of D and C activities in vitro. These results indicate that the N-terminal D/C domain of C1-THF synthase requires the C-terminal 10-formyl-THF synthetase domain for stable catalytic activity in vitro.

Cisplatin-induced apoptosis by translocation of endogenous Bax in mouse collecting duct cells.

cis-platinum(II) (cis-diammine dichloroplatinum; cisplatin) is a potent antitumor compound that is widely used for the treatment of many malignancies. An important side-effect of cisplatin is nephrotoxicity, which results from injury to renal tubular epithelial cells and can be manifested as either acute renal failure or a chronic syndrome characterized by renal electrolyte wasting. Recently, apoptosis has been recognized as an important mechanism of cell death mediating the antitumor effect of cisplatin. This study was undertaken to examine the mechanisms of cell death induced by cisplatin in M-1 cells, which were derived from the outer cortical collecting duct cells of SV40 transgenic mice. Treatment of M-1 cells with high concentrations of cisplatin (0.5 and 1 mM) for 2 hr led to necrotic cell death, whereas a 24-hr treatment with 5-20 microM cisplatin led to apoptosis. Antioxidants protected against cisplatin-induced necrosis, but not apoptosis, indicating that reactive oxygen species play a role in mediating necrosis but not apoptosis induced by cisplatin and that the mechanism of cell death induced by cisplatin is concentration dependent. The low concentrations of cisplatin, which induced apoptosis in M-1 cells, did not affect the expression levels of Bcl-2-related proteins and did not activate c-Jun NH2-terminal kinase (SAPK/JNK). Cisplatin induced the translocation of endogenous Bax from the cytosolic to the membrane fractions and, subsequently, the release of cytochrome c. Overexpression of Bcl-2 blocked cisplatin-induced apoptosis and Bax translocation. These observations suggest that the subcellular redistribution of Bax is a critical event in the apoptosis induced by cisplatin.

Atrial fibrillation surgery simplified with cryoablation to improve left atrial function.

BACKGROUND: The Maze procedure restores atrial fibrillation to normal sinus rhythm. However, concurrent left atrial functional recovery is not always achieved. To address this limitation, a modification using linear cryoablation is described. METHODS: Between July 1997 and December 1999, 83 patients received atrial fibrillation surgery in association with mitral valve surgery with or without additional concurrent procedures by either the conventional technique, group I (n = 30) or the modified technique, group II (n = 53). Onset of sinus conversion and echocardiographic assessment of postoperative left ventricular function, left atrial size, and mitral A-wave velocity were compared in the early postoperative period and 6 months after surgery. RESULTS: Sinus conversion occurred significantly earlier in group II, 2.4 +/- 5 days versus group I, 7.0 +/- 10 days. The mean transmitral A-wave velocity and the incidence of A-wave appearance in the early postoperative period and 6 months postoperatively were greater in group II than group I. CONCLUSIONS: With the current modification, restoration of sinus rhythm and superior left atrial contractile function occurred earlier than with the standard Maze III technique.