Mitosis encompasses key molecular changes including chromatin condensation, nuclear envelope breakdown, and reduced transcription levels. Immediately after mitosis, the interphase chromatin structure is reestablished and transcription resumes. The reestablishment of the interphase chromatin is probably achieved by "bookmarking," i.e., the retention of at least partial information during mitosis. To gain a deeper understanding of the contribution of histone modifications to the mitotic bookmarking process, we merged proteomics, immunofluorescence, and ChIP-seq approaches. We focused on key histone modifications and employed HeLa-S3 cells as a model system. Generally, in spite of the general hypoacetylation observed during mitosis, we observed a global concordance between the genomic organization of histone modifications in interphase and mitosis, suggesting that the epigenomic landscape may serve as a component of the mitotic bookmarking process. Next, we investigated the nucleosome that enters nucleosome depleted regions (NDRs) during mitosis. We observed that in ∼60% of the NDRs, the entering nucleosome is distinct from the surrounding highly acetylated nucleosomes and appears to have either low levels of acetylation or high levels of phosphorylation in adjacent residues (since adjacent phosphorylation may interfere with the ability to detect acetylation). Inhibition of histone deacetylases (HDACs) by the small molecule TSA reverts this pattern, suggesting that these nucleosomes are specifically deacetylated during mitosis. Altogether, by merging multiple approaches, our study provides evidence to support a model where histone modifications may play a role in mitotic bookmarking and uncovers new insights into the deposition of nucleosomes during mitosis.

Objective: To analyze the factors most related to the incidence of neonatal sepsis at Ulin Hospital of Banjarmasin in 2016 Method: This research used Rapid Miner simulation model with population of all newborns at Ulin Hospital of Banjarmasin in 2016 and the sample size was 210 infants consisting of 105 infants with neonatal sepsis and 105 infants without neonatal sepsis. The analysis used Algorithm C.45 (Decision Tree) to see the accuracy level, and Root Mean Squared Error. Results: The factors most closely related with the incidence of neonatal sepsis were gestational age ≤ 33.5 weeks with the strong power of relationship (0.643), accuracy rate of 80.95%, and mean error rate of 0.401. Conclusion: Infants born with a gestational age < 33.5 weeks are at risk of having neonatal sepsis while those born with a gestation age > 33.5 weeks are at risk when the born with asphyxia complication, birth weight ≤ 3875, and temperature> 37 o C accompanied by labor trauma. Infants born with body temperature ≤ 37 o C are at risk of having neonatal sepsis when it is accompanied by pregnancy complication such as premature rupture of membranes.

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Background: It is important to study the epidemiologic features and predisposing factors of corneal ulcer and subsequently to find out its causative agents and their antimicrobial susceptibility patterns in a given community, climate and culture. Aims & Objectives: This prospective study of 100 cases of corneal ulcer was undertaken to bring out the bacterial and fungal prevalence among different age groups. Materials and Methods: Corneal scrapings were collected from all patients. One corneal swab and three corneal scrapings were collected. Direct examination of samples was done by potassium hydroxide wet mount and gram stained smear and then inoculated onto blood agar, MacConkey's agar and Saboraud's dextrose agar media. Identification of fungal growth finally was done based on its macroscopic and microscopic features. Bacterial colonies were identified by Gram staining and standard biochemical tests and antimicrobial susceptibility testing was carried out for each bacterial isolate. Results: Out of total 100 specimens of corneal ulcer, only 55% cases were found to be culture positive in which bacteria were more frequently isolated than fungi. Staphylococcus aureus and Aspergillus spp were the most frequent bacterium and fungus. The incidence was higher in males and in age group of >40-60 years. While S. aureus was found to be most sensitive to vancomycin, Staphylococcus epidermis was most sensitive to cefazoline. Conclusion: S. aureus and Aspergillus spp were the most common isolate to be associated with corneal ulcer, and the incidence was higher in rural population, especially farmers, who were constantly exposed to vegetative matter.

Mitosis encompasses key molecular changes including chromatin condensation, nuclear envelope breakdown and reduced transcription levels. Immediately after mitosis, the interphase chromatin structure is reestablished and transcription resumes. The reestablishment of the interphase chromatin requires 'bookmarking', i.e., the retention of at least partial information during mitosis.Yet, while recent studies demonstrate that chromatin accessibility is generally preserved during mitosis and is only locally modulated, the exact details of the bookmarking process and its components are still unclear. To gain a deeper understanding of the mitotic bookmarking process, we merged proteomics, immunofluorescence, and ChIP-seq approaches to study the mitotic and interphase organization in human cells. We focused on key histone modifications, and employed the HeLa-S3 cells as a model system. Generally, we observed a global concordance between the genomic organization of histone modifications in interphase and mitosis, yet the abundance of the two types of modifications we investigated was different. Whereas histone methylation patterns remain highly similar, histone acetylation patterns show a general reduction while maintaining their genomic organization. In line with a recent study demonstrating that minimal transcription is retained during mitosis, we show that RNA polymerase II does not fully disassociate from the genome, but rather maintains its genomic localization at reduced levels. Next, we followed up on previous studies demonstrating that nucleosome depleted regions (NDRs) become occupied by a nucleosome during mitosis. Surprisingly, we observed that the nucleosome introduced into the NDR during mitosis encompasses a distinctive set of histone modifications, differentiating it from the surrounding nucleosomes. We show that the nucleosomes in the vicinity of the NDR appear to both shift into the NDR during mitosis and undergo deacetylation. HDAC inhibition by the small molecule TSA reverts the deacetylation pattern of the shifted nucleosome. Taken together, our results demonstrate that the epigenomic landscape can serve as a major component of the mitotic bookmarking process, and provide evidence for a mitotic deposition and deacetylation of the nucleosomes surrounding the NDR.

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Mitosis comprises multiple changes, including chromatin condensation and transcription reduction. Intriguingly, while histone acetylation levels are reduced during mitosis, the mechanism of this reduction is unclear. We studied the mitotic regulation of H3K9ac by using inhibitors of histone deacetylases. We evaluated the involvement of the targeted enzymes in regulating H3K9ac during mitotic stages and cytokinesis by immunofluorescence and immunoblots. We identified HDAC2, HDAC3 and SIRT1 as modulators of the mitotic levels of H3K9ac. HDAC2 inhibition increased H3K9ac levels in prophase, whereas HDAC3 or SIRT1 inhibition, increased H3K9ac levels in metaphase. Next, we performed ChIP-seq in mitotic cells following targeted inhibition of these histone deacetylases. While the genomic areas impacted by HDAC2 and HDAC3 were mostly concordant, a subset of loci were unique to each enzyme. Interestingly, HDAC3-specific targets were enriched for genes involved in mitosis regulation. Our results support a model in which H3K9 deacetylation is a stepwise process - at prophase HDAC2 modulates most transcription-associated H3K9ac-marked loci and at metaphase HDAC3 maintains the reduced acetylation, whereas SIRT1 potentially regulates H3K9ac by impacting HAT activity.

Histone acetylation levels are reduced during mitosis. To study the mitotic regulation of H3K9ac, we used an array of inhibitors targeting specific histone deacetylases. We evaluated the involvement of the targeted enzymes in regulating H3K9ac during all mitotic stages by immunofluorescence and immunoblots. We identified HDAC2, HDAC3, and SIRT1 as modulators of H3K9ac mitotic levels. HDAC2 inhibition increased H3K9ac levels in prophase, whereas HDAC3 or SIRT1 inhibition increased H3K9ac levels in metaphase. Next, we performed ChIP-seq on mitotic-arrested cells following targeted inhibition of these histone deacetylases. We found that both HDAC2 and HDAC3 have a similar impact on H3K9ac, and inhibiting either of these two HDACs substantially increases the levels of this histone acetylation in promoters, enhancers, and insulators. Altogether, our results support a model in which H3K9 deacetylation is a stepwise process—at prophase, HDAC2 modulates most transcription-associated H3K9ac-marked loci, and at metaphase, HDAC3 maintains the reduced acetylation, whereas SIRT1 potentially regulates H3K9ac by impacting HAT activity.