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The study aimed to evaluate tobacco use, attitudes, knowledge, and perceptions about tobacco control policies and smoking cessation counseling among dental students in Morocco. This cross-sectional study was conducted at the Dentistry Faculty of the Mohammed VI University of Health Sciences of Casablanca, using the Global Health Professions Student Survey (GHPSS) tool. Participants completed a self-administered survey questionnaire, including information on socio-demographic characteristics, tobacco use, exposure to secondhand smoke, attitudes, behavior and cessation, curriculum, and training. A total of 426 dental students were included in the study. Over 15% of the participants were current smokers, and 31.2% had tried smoking at least once. About 29.3% reported having been exposed to secondhand smoke in family settings and 49.5% in other environments. The majority of the students had felt that health professionals were role models for their patients. However, only 20% had felt they had received formal training in smoking cessation approaches. More than 70% of smokers had tried to quit smoking in the past year; however, only 41.7% reported having received help or advice. It is crucial that education and public health officials join efforts to plan and carry out programs aimed at training dental students in evidence-based cessation counseling methods, in order to change their own smoking behavior and assist their future patients. Improving dental school curriculums with regard to tobacco use prevention and cessation is also a powerful means of alleviating the national burden of cancer. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the knowledge, perceptions, and satisfaction of Moroccan women who resided the Meknes-Tafilalt region regarding a newly implemented breast cancer screening program in the region. The study was conducted in 24 randomly selected health centers from Meknes-Tafilalt region, Morocco. We targeted all women who resided in the region of the program and who met the inclusion criteria to participate in the screening program. Data was collected through a face-to-face questionnaire. In this study, 318 women were included. Results revealed moderate knowledge of breast cancer and the screening program. Most of the participants (90.5%) had heard of the breast cancer screening program. Only 33.6% of women declared that they are well informed about the program. Fear emotions related to breast cancer were reported by 93.1% of participants. About 82% of women accept to repeat a screening test every 2 years. Recommending the breast cancer screening test to their family and friends was stated by nearly 90% of women. The majority of women (94.9%) expressed their satisfaction about the screening test activities provided by health centers. Our results showed a moderate level of knowledge about breast cancer, a very positive attitude, and high overall satisfaction towards the breast cancer screening program in the Meknes-Tafilalt region. These results can guide development of appropriate breast cancer prevention strategies and sensibilisation campaigns in Morocco. [ABSTRACT FROM AUTHOR]

Cancer is the second leading cause of death in Morocco after cardiovascular diseases. Changes associated with societal and economic development, longevity of the population, and lifestyle changes contribute to increasing the burden of cancer in the Morocco. Despite the advances and achievements in cancer care in Morocco, more efforts are needed to better treat, control, and prevent cancer in Morocco. This manuscript illustrates the professional cancer education activities in Morocco over the past 10 years. The manuscript also illustrates the current cancer education and the needed future directions in the field in this middle-income country that is undergoing significant epidemiologic and lifestyle transitions and projections for increasing cancer incidence and mortality in the next few decades. [ABSTRACT FROM AUTHOR]

Heterochromatin protein 1β (HP1β), encoded by the Cbx1 gene, has been functionally linked to chromatin condensation, transcriptional regulation, and DNA damage repair. Here we report that testis-specific Cbx1 conditional knockout (Cbx1 cKO) impairs male germ cell development in mice. Depletion of HP1β negatively affected sperm maturation and increased seminiferous tubule degeneration in Cbx1 cKO mice. In addition, the spermatogonia have elevated γ-H2AX foci levels as do Cbx1 deficient mouse embryonic fibroblasts (MEFs) as compared to wild-type (WT) control MEFs. The increase in γ-H2AX foci in proliferating Cbx1 cKO cells indicates defective replication-dependent DNA damage repair. Depletion or loss of HP1β from human cells and MEFs increased DNA replication fork stalling and firing of new origins of replication, indicating defective DNA synthesis. Taken together, these results suggest that loss of HP1β in proliferating cells leads to DNA replication defects with associated DNA damage that impact spermatogenesis. [ABSTRACT FROM AUTHOR]

Background: There is convincing evidence demonstrating that body size characteristics such as adiposity and height are associated with breast cancer in westernized countries. However, little is known about this relationship in North African countries currently undergoing nutritional transition and industrialization. The aim of this study was to explore associations between various body size characteristics, silhouette trajectories and the risk of breast cancer among Moroccan women. Methods: In this case–control study conducted in the Fez region (2016–2017), detailed measures of body size were collected for 300 cases of breast cancer and 300 matched controls. Unconditional logistic regression was used to assess the association between body size and breast cancer risk adjusting for confounding factors. Results: Higher waist circumference and hip circumference were positively associated with breast cancer risk in pre- (highest [T3] vs. lowest tertile [T1]: OR = 2.92, 95% confidence intervals [CI]: 1.33–6.42; OR = 3.00, 95% CI: 1.42–6.33, respectively) and post-menopausal women (T3 vs. T1: OR = 4.46, 95% CI: 1.86–10.66; OR = 4.08, 95% CI: 1.76–9.42, respectively). Body shape at younger ages (6–11 years) was inversely associated with the risk of breast cancer in premenopausal women (large vs. lean silhouette: OR = 0.31, 95% CI: 0.12–0.80). Women with the greatest increase in body shape trajectory had higher risk for both pre- and post-menopausal breast cancer (T3 vs. T1: OR = 2.74, 95% CI: 1.03–7.26; OR = 3.56, 95% CI: 1.34–9.44, respectively). Conclusion: Our findings suggest that adiposity, body shape at younger ages, and silhouette trajectory may play a role in the development of pre- and post-menopausal breast cancer among Moroccan women. Larger-scale prospective studies are needed to confirm our findings and to explore these associations with breast cancer subtypes. [ABSTRACT FROM AUTHOR]

Bacteria are unicellular organisms that do not show compartmentalization of the genetic material and other cellular organelles as seen in higher organisms. Earlier, bacterial genomes were defined as single circular chromosome and extrachromosomal plasmids. Recently, many bacteria were found harbouring multipartite genome system and the numbers of copies of genome elements including chromosomes vary from one to several per cell. Interestingly, it is noticed that majority of multipartite genome-harbouring bacteria are either stress tolerant or pathogens. Further, it is observed that the secondary genomes in these bacteria encode proteins that are involved in bacterial genome maintenance and also contribute to higher stress tolerance, and pathogenicity in pathogenic bacteria. Surprisingly, in some bacteria the genes encoding the proteins of classical homologous recombination pathways are present only on the secondary chromosomes, and some do not have either of the classical homologous recombination pathways. This review highlights the presence of ploidy and multipartite genomes in bacterial system, the underlying mechanisms of genome maintenance and the possibilities of these features contributing to higher abiotic and biotic stress tolerance in these bacteria. [ABSTRACT FROM AUTHOR]

Pulmonary arterial hypertension (PAH) is a rare disorder with a poor prognosis. Deleterious variation within components of the transforming growth factor-β pathway, particularly the bone morphogenetic protein type 2 receptor (BMPR2), underlies most heritable forms of PAH. To identify the missing heritability we perform whole-genome sequencing in 1038 PAH index cases and 6385 PAH-negative control subjects. Case-control analyses reveal significant overrepresentation of rare variants in ATP13A3, AQP1 and SOX17, and provide independent validation of a critical role for GDF2 in PAH. We demonstrate familial segregation of mutations in SOX17 and AQP1 with PAH. Mutations in GDF2, encoding a BMPR2 ligand, lead to reduced secretion from transfected cells. In addition, we identify pathogenic mutations in the majority of previously reported PAH genes, and provide evidence for further putative genes. Taken together these findings contribute new insights into the molecular basis of PAH and indicate unexplored pathways for therapeutic intervention. [ABSTRACT FROM AUTHOR]

The multipartite genome of Deinococcus radiodurans forms toroidal structure. It encodes topoisomerase IB and both the subunits of DNA gyrase (DrGyr) while lacks other bacterial topoisomerases. Recently, PprA a pleiotropic protein involved in radiation resistance in D. radiodurans has been suggested for having roles in cell division and genome maintenance. In vivo interaction of PprA with topoisomerases has also been shown. DrGyr constituted from recombinant gyrase A and gyrase B subunits showed decatenation, relaxation and supercoiling activities. Wild type PprA stimulated DNA relaxation activity while inhibited supercoiling activity of DrGyr. Lysine133 to glutamic acid (K133E) and tryptophane183 to arginine (W183R) replacements resulted loss of DNA binding activity in PprA and that showed very little effect on DrGyr activities in vitro. Interestingly, wild type PprA and its K133E derivative continued interacting with GyrA in vivo while W183R, which formed relatively short oligomers did not interact with GyrA. The size of nucleoid in PprA mutant (1.9564 ± 0.324 µm) was significantly bigger than the wild type (1.6437 ± 0.345 µm). Thus, we showed that DrGyr confers all three activities of bacterial type IIA family DNA topoisomerases, which are differentially regulated by PprA, highlighting the significant role of PprA in DrGyr activity regulation and genome maintenance in D. radiodurans. [ABSTRACT FROM AUTHOR]

Peroxisomes are highly metabolic, autonomously replicating organelles that generate reactive oxygen species (ROS) as a by-product of fatty acid β-oxidation. Consequently, cells must maintain peroxisome homeostasis, or risk pathologies associated with too few peroxisomes, such as peroxisome biogenesis disorders, or too many peroxisomes, inducing oxidative damage and promoting diseases such as cancer. We report that the PEX5 peroxisome import receptor binds ataxia-telangiectasia mutated (ATM) and localizes this kinase to the peroxisome. In response to ROS, ATM signalling activates ULK1 and inhibits mTORC1 to induce autophagy. Specificity for autophagy of peroxisomes (pexophagy) is provided by ATM phosphorylation of PEX5 at Ser 141, which promotes PEX5 monoubiquitylation at Lys 209, and recognition of ubiquitylated PEX5 by the autophagy adaptor protein p62, directing the autophagosome to peroxisomes to induce pexophagy. These data reveal an important new role for ATM in metabolism as a sensor of ROS that regulates pexophagy. [ABSTRACT FROM AUTHOR]

PprA, a pleiotropic protein involved in radioresistance of Deinococcus radiodurans was detected in multiprotein DNA processing complex identified from this bacterium. pprA mutant expressing GFP-PprA could restore its wild type resistance of γ radiation. Under normal conditions, GFP-PprA expressing cells showed PprA localization on both septum trapped nucleoids (STN) and nucleoids located elsewhere (MCN). Cell exposed to 4 kGy γ radiation showed nearly 2 h growth lag and during this growth arrest phase, the majority of the cells had GFP-PprA located on MCN. While in late phase (∼120 min) PIR cells, when cells are nearly out of growth arrest, PprA was maximally found with STN. These cells when treated with nalidixic acid showed diffused localization of PprA across the septum. gyrA disruption mutant of D. radiodurans showed growth inhibition, which increased further in gyrA pprA mutant. Interestingly, gyrA mutant showed ∼20-fold less resistance to γ radiation as compared to wild type, which did increase further in gyrA pprA mutant. These results suggested that PprA localization undergoes a dynamic change during PIR, and its localization on nucleoid near septum and functional interaction with gyrase A might suggest a mechanism that could explain PprA role in genome segregation possibly through topoisomerase II. [ABSTRACT FROM AUTHOR]

Bacterial genome segregation and cell division has been studied mostly in bacteria harbouring single circular chromosome and low-copy plasmids. Deinococcus radiodurans, a radiation-resistant bacterium, harbours multipartite genome system. Chromosome I encodes majority of the functions required for normal growth while other replicons encode mostly the proteins involved in secondary functions. Here, we report the characterization of putative P-loop ATPase (ParA2) encoded on chromosome II of D. radiodurans. Recombinant ParA2 was found to be a DNA-binding ATPase. E. coli cells expressing ParA2 showed cell division inhibition and mislocalization of FtsZ-YFP and those expressing ParA2-CFP showed multiple CFP foci formation on the nucleoid. Although, in trans expression of ParA2 failed to complement SlmA loss per se, it could induce unequal cell division in slmA minCDE double mutant. These results suggested that ParA2 is a nucleoid-binding protein, which could inhibits cell division in E. coli by affecting the correct localization of FtsZ and thereby cytokinesis. Helping slmA minCDE mutant to produce minicells, a phenotype associated with mutations in the 'Min' proteins, further indicated the possibility of ParA2 regulating cell division by bringing nucleoid compaction at the vicinity of septum growth. [ABSTRACT FROM AUTHOR]

The homologous recombination (HR) repair pathway maintains genetic integrity after DNA double-strand break (DSB) damage and is particularly crucial for maintaining fidelity of expressed genes. Histone H4 acetylation on lysine 16 (H4K16ac) is associated with transcription, but how pre-existing H4K16ac directly affects DSB repair is not known. To answer this question, we used CRISPR/Cas9 technology to introduce I-SceI sites, or repair pathway reporter cassettes, at defined locations within gene-rich (high H4K16ac/euchromatin) and gene-poor (low H4K16ac/heterochromatin) regions. The frequency of DSB repair by HR is higher in gene-rich regions. Interestingly, artificially targeting H4K16ac at specific locations using gRNA/dCas9-MOF increases HR frequency in euchromatin. Finally, inhibition/depletion of RNA polymerase II or Cockayne syndrome B protein leads to decreased recruitment of HR factors at DSBs. These results indicate that the pre-existing H4K16ac status at specific locations directly influences the repair of local DNA breaks, favoring HR in part through the transcription machinery. Nobuo Horikoshi et al. report the use of CRISPR/Cas9 to insert cleavage and repair sites in gene-rich and gene-poor regions in human cell lines. They show that the frequency of double-stranded break repair by homologous recombination is higher in gene-rich regions with high levels of H4K16ac marks. [ABSTRACT FROM AUTHOR]