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The mitochondrial electron transport chain consists of the classical protein complexes (I-IV) that facilitate the flow of electrons and coupled oxidative phosphorylation to produce metabolic energy. The canonical route of electron transport may diverge by the presence of alternative components to the electron transport chain. The following study comprises the bioinformatic identification and functional characterization of a putative alternative oxidase in the smut fungus Sporisorium reilianum f. sp. zeae. This alternative respiratory component has been previously identified in other eukaryotes and is essential for alternative respiration as a response to environmental and chemical stressors, as well as for developmental transitionaoxs during the life cycle of an organism. A growth inhibition assay, using specific mitochondrial inhibitors, functionally confirmed the presence of an antimycin-resistant/salicylhydroxamic acid (SHAM)-sensitive alternative oxidase in the respirasome of S. reilianum. Gene disruption experiments revealed that this enzyme is involved in the pathogenic stage of the fungus, with its absence effectively reducing overall disease incidence in infected maize plants. Furthermore, gene expression analysis revealed that alternative oxidase plays a prominent role in the teliospore developmental stage, in agreement with favoring alternative respiration during quiescent stages of an organism's life cycle.

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Alternative splicing of exon24 (E24) of myosin phosphatase targeting subunit 1 (Mypt1) by setting sensitivity to nitric oxide (NO)/cGMP-mediated relaxation is a key determinant of smooth muscle function. Here we defined expression of myosin phosphatase (MP) subunits and isoforms by creation of new genetic mouse models, assay of human and mouse tissues, and query of public databases. A Mypt1-LacZ reporter mouse revealed that Mypt1 transcription is turned on early in development during smooth muscle differentiation. Mypt1 is not as tightly restricted in its expression as smooth muscle myosin heavy chain (Myh11) and its E6 splice variant. Mypt1 is enriched in mature smooth versus nonmuscle cells. The E24 splice variant and leucine zipper minus protein isoform that it encodes is enriched in phasic versus tonic smooth muscle. In the vascular system, E24 splicing increases as vessel size decreases. In the gastrointestinal system, E24 splicing is most predominant in smooth muscle of the small intestine. Tissue-specific expression of MP subunits and Mypt1 E24 splicing is conserved in humans, whereas a splice variant of the inhibitory subunit (CPI-17) is unique to humans. A Mypt1 E24 mini-gene splicing reporter mouse generated to define patterns of E24 splicing in smooth muscle cells (SMCs) dispersed throughout the organ systems was unsuccessful. In summary, expression of Mypt1 and splicing of E24 is part of the program of smooth muscle differentiation, is further enhanced in phasic smooth muscle, and is conserved in humans. Its low-level expression in nonmuscle cells may confound its measurement in tissue samples.

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Ustilago maydis can utilize nitrate as a sole source of nitrogen. This process is initiated by transporting nitrate from the extracellular environment into the cell by a nitrate transporter and followed by a two-step reduction of nitrate to ammonium via nitrate reductase and nitrite reductase enzymes, respectively. Here, we characterize the genes encoding nitrate transporter, um03849 and nitrite reductase, um03848 in U. maydis based on their roles in mating and virulence. The deletion mutants for um03848, um03849 or both genes were constructed in mating compatible haploid strains 1/2 and 2/9. In addition, CRISPR-Cas9 gene editing technique was used for um03849 gene to create INDEL mutations in U. maydis mating strains. For all the mutants, phenotypes such as growth ability, mating efficiency and pathogenesis were examined. The growth of all the mutants was diminished when grown in a medium with nitrate as the source of nitrogen. Although no clear effects on haploid filamentation or mating were observed for either single mutant, double Δum03848 Δum03849 mutants showed reduction in mating, but increased filamentation on low ammonium, particularly in the 1/2 background. With respect to pathogenesis on the host, all the mutants showed reduced degrees of disease symptoms. Further, when the deletion mutants were paired with wild type of opposite mating-type, reduced virulence was observed, in a manner specific to the genetic background of the mutant's progenitor. This background specific reduction of plant pathogenicity was correlated with differential expression of genes for the mating program in U. maydis.

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INTRODUCTION: Resin-bonded fixed dental prostheses have an advantage over conventional fixed dental prostheses in terms of conservation of tooth structure but many clinicians refrain from using this treatment plan over the concern of the retention of those prostheses. In anterior region, it has better survival rate because of the less masticatory force. This study was conducted to find out the survival of resin-bonded fixed metal-ceramic dental prostheses placed in anterior region of a tertiary care hospital. METHODS: A descriptive cross-sectional study was carried out in a tertiary care hospital from September 2020 to February 2021. Ethical approval was taken from the Institutional Review Committee of Kantipur Dental College (reference number: 29/020). One hundred fifty-five patients who underwent prosthesis placement at least 5 years ago in the institution were identified from the hospital record and called, out of which only 80 agreed to be enrolled in the study. Consent was taken and data were collected using questionnaires filled by investigators and analyzed using the Statistical Package for the Social Sciences version 25. Point estimate at 90% Confidence Interval was calculated along with frequency and percentage for binary data. RESULTS: Out of 80 patients, the prostheses survived in 72 (90%) (90% Confidence Interval 84.48-95.51). The mean duration for which the prostheses survived in the mouth was 73.33±13.493 months with minimum 28 and maximum 98 months. CONCLUSIONS: This study showed that the survival after five years of resin-bonded fixed dental metal ceramic was high. The study's findings are comparable with international studies.

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Mating-types allow single-celled eukaryotic organisms to distinguish self from non-self in preparation for sexual reproduction. The components of mating-type loci provide initial self/non-self-recognition through pheromone and receptor interactions that control early cell fusion events. However, they may also provide a second level of scrutiny that requires differences in alleles leading to production of a transcription factor required for successful downstream developmental pathways after initial cell fusion. Interestingly, the protein subunits of these transcription factors have not been thoroughly examined for their roles, if any, in the haploid cells themselves. In Ustilago maydis, the causative agent of galls in maize plants, the b locus, encoding bEast (bE) and bWest (bW), components of the eventual requisite transcription factor, has been extensively studied for its role in formation of the stable dikaryon after mating and subsequent pathogenic program. Little is known, however, about any roles for bE or bW in haploid cells. Since mating in fungi is often induced under conditions of nitrogen starvation, we have explored connections between the b locus and the nitrogen-sensing and response pathways in U. maydis. We previously identified a connection in haploid cells between the b locus and Ump2, the high-affinity transceptor, a protein that both transports ammonium and triggers filamentous growth as a response to nitrogen starvation. Deletion of the entire b locus abrogates the filamentous response to low ammonium, a phenotype that is rescued by overexpression of Ump2. Here we further investigated the individual roles of bE and bW in haploid cells. We show that bE and bW are expressed differentially in haploid cells starved for ammonium. Their respective deletion elicits different effects on transcription of mating and pathogenic-related genes and, importantly, on the degree of pathogenic development in host plants. This is the first demonstration of a role for these mating locus components on haploid development and the first to demonstrate a connection to the ammonium transceptors.

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INTRODUCTION: An individual may feel stressed when he/she is unable to cope with past, present, and future situations. A high level of stress in dental students is due to the fact that dental students need to acquire diverse proficiencies such as theoretical knowledge, clinical competencies, and interpersonal skills. So, this study was conducted to find out the prevalence of perceived stress among undergraduate students in a dental college. METHODS: A descriptive cross-sectional study was conducted among first-year to final year students of a tertiary care centre from May-August 2020. The sample size was calculated to be 177. Convenience sampling technique was used. Data collection was done after taking ethical approval from the institutional review committee (Ref no.21/020). Data collection was done by using a selfadministered, modified Dental Environmental Stress Questionnaire. Data analysis was done by using Statistical Package of Social Sciences version 20 software. Point estimate at 95% Confidence Interval was calculated along with frequency and proportion for binary data. RESULTS: The prevalence of perceived stress was found to be 80.55 (45%) at 95% Confidence Interval (37.71-52.28). Students perceived more stress from the domain related to personal factors i.e. fear of failing 78 (43.6%), academic factors i.e. examination and grades 71 (39.7%), unable to catch up with the back lock work 68 (38%), and for the clinical phase students, patients not coming or coming too late was most stressful 69 (60%) followed by getting an ideal case for clinical examination 60 (52.2%). CONCLUSIONS: Overall stress levels were slight to severe and were comparatively higher in clinical phase students due to factors related to patients.

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INTRODUCTION: Self-medication means the use of medications for the treatment of any disease on their own, without consulting any healthcare professional. At times self-medication can be useful if practiced correctly by saving time and money, whereas disadvantages often occur due to lack of evaluation by trained medical professionals and delay ineffective treatment and can result in unnecessary expenses and drug dependence. This study was conducted to find out the self-medication behavior and its associated factors among patients visiting a dental hospital in Kathmandu. METHODS: A hospital-based, cross-sectional study was conducted on 265 patients in Kantipur Dental College from December 2019 to January 2020 among the patients attending the dental Out Patient Department. Ethical clearance was obtained from the Institutional Review Committee of Kantipur Dental College. A convenience sampling technique was used. Proformas were prepared in English, translated to Nepali and re-translated to English by the back-translation method. Data entry was done in Microsoft Excel and analysis in SPSS 20. Descriptive statistics was done. RESULTS: The prevalence of self-medication practice was found to be 166 (62.6%). Out of total participants, 99 (59.6%) consumed medicines for few days only and the most common triggering factor was found to be toothache in 101 (60.8%) participants. The most common reason for selfmedication was found to be a previous experience of treating similar illnesses. CONCLUSIONS: The prevalence of self-medication was found to be low as compared to the study done in similar settings. Self-medication practice is a sensitive issue that hasn't been given the required consideration.

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