Effect of different levels of citric acid on quality and storage stability of sugar and jaggery based papaya (Carica papaya L.) fruit bar

A study was undertaken to evaluate the effect of different level of citric acid and packaging material on physico chemical quality, sensory quality and shelf life of developed papaya fruit bar .The study revealed that the moisture content (19.06% to 16.95% in PET jars – 19.06% to 17.06% in glass jars), TSS (64.17 to 69.30°Brix in PETjars and 64.17 to 69.46°Brix in glass jars), Vitamin- C (55.30 to 45.80 mg/100mg in PET jars and 55.30 to 46.75 mg/100mg in glass jars) and total plate count decreased with increasing the level of citric acid from 0.5 to 1.0% after 90 days of storage in. During storage there was a reduction in moisture content, pH and vitamin-C, where as TSS (total soluble solids), optical density and total plate count increased during storage. No microbial detection in developed fresh fruit bar was found. The organoleptic score of the bar samples in glass jars at 0.75% citric acid level was found to be higher followed by samples packed in PET jars and the developed fruit bar was well acceptable even after 90 days of storage. The result indicated that sugar50+jaggery50 at 0.75 percent citric acid level gave better products after 90 days of storage followed by sugar50+jaggery50 at 0.5 percent and sugar50+jaggery50 at 1.0 percent

Identification and functional characterization of protein domains in the transcription factor TWIST

Saethre-Chotzen syndrome is an autosomal dominant inherited disorder with premature fusion of cranial sutures. It is caused by nucleotide sequence changes within or in proximity of the TWIST1 gene. This gene encodes for a bHLH transcription factor, which inhibits osteogenic differentiation by transcriptional control of various target genes. The aim of my work is to characterize functional domains in TWIST protein, and to determine the interacting partner for TWIST and its motifs particularly NSEEE and WR. The present study was thus undertaken to determine how TWIST1 gene mutations affect protein function. Evolutionary alignment of Twist proteins from different species, indicate TWIST contain 4 additional conserved regions such as NSEEE, NLS1, NLS2, and WR-domain besides the bHLH motif. The bHLH domain is thought to be responsible for heterodimerization with other bHLH proteins such as E12 protein or SEF2 protein. The functions of NSEEE, NLS1, NLS2, and conserved WR motifs are poorly understood at present. First, I focused on functional characterization of the NLS1 and NLS2 domains as potential nuclear localization signals in TWIST., Specifically the effects of various NLS substitutions in TWIST on cellular localization was assayed by immunoflourescence assay. In particular, TWIST NLS1 altered at amino acid position K38R was found to be retained in the cytoplasm of transiently transfected U2-OS cells, suggesting that NLS1 is functional and essential for the nuclear transport of TWIST. Additionally, to understand the role of the TWIST NLS2 in nuclear localization, amino acid at positions 73, 76 and 77 were substituted in this motif. These results demonstrated that substitution at NLS2 position 76 does not play an essential role in the nuclear localization of TWIST, in contrast to the K73R and K77R that inhibit nuclear accumulation. Although K76R mutants cannot inhibit nuclear localization by itself, we demonstrate it plays a synergistic role with the NLS1 K38R mutation to further reduce nuclear localization. This synergistic effect is consistent with the observation that combined K38R (NLS1) and K76R (NLS2) mutants dramatically reduced nuclear localization, further suggesting that both NLS1 and NLS2 work together in regulating nuclear localization of TWIST protein. TWIST belongs to class B bHLH proteins which are known to form stable heterodimers with members of class A bHLH transcription factors including gene products of E12 and E47, respectively. Accordingly, the subcellular localization of NLS1 and NLS2 in TWIST protein was investigated in U2-OS cells following co-transfection with E12. The cotransfections with heterodimerization partner E12 and NLS1-mutated TWIST led to a compensation of the mislocalization. The second aim of my work was to identify the interacting proteins that could influence the functionality of TWIST using yeast-two-hybrid assay. I wanted to determine if the TWIST protein or its conserved motifs interact with other regulatory proteins to help to regulate the TWIST transcriptional activity. Using the entire coding sequence of TWIST1 gene, an interesting candidate was found belonging to the class A bHLH transcription factors that includes the SEF2 gene product. The direct interaction of SEF2 with TWIST was verified in a yeast mating assay and then confirmed in an in vivo NLS-rescue assay using U2-OS cells, showing that SEF2 forms a heterodimer with TWIST protein and co-localized into the nucleus. Furthermore, two more highly conserved TWIST motifs NSEEE and WR were analyzed individually to find out their interacting proteins and their role in regulating the TWIST1 transcriptional activity. I found more than 1000 yeast clones for NSEEE motif and 120 clones for WR motif. The second screening of the yeast clones suggested some promising candidates protein as interacting partners with the NSEEE motif such as ETV5, SURF4, Spastin, Metalloproteinase 2, and ALR-like protein mRNA. By contrast I could not detect any interesting interacting partners with the WR domain. A possible explanation may be the requirement of bHLH to mediate WR interaction with other proteins

Low Degree Metabolites Explain Essential Reactions and Enhance Modularity in Biological Networks

Recently there has been a lot of interest in identifying modules at the level of genetic and metabolic networks of organisms, as well as in identifying single genes and reactions that are essential for the organism. A goal of computational and systems biology is to go beyond identification towards an explanation of specific modules and essential genes and reactions in terms of specific structural or evolutionary constraints. In the metabolic networks of E. coli, S. cerevisiae and S. aureus, we identified metabolites with a low degree of connectivity, particularly those that are produced and/or consumed in just a single reaction. Using FBA we also determined reactions essential for growth in these metabolic networks. We find that most reactions identified as essential in these networks turn out to be those involving the production or consumption of low degree metabolites. Applying graph theoretic methods to these metabolic networks, we identified connected clusters of these low degree metabolites. The genes involved in several operons in E. coli are correctly predicted as those of enzymes catalyzing the reactions of these clusters. We independently identified clusters of reactions whose fluxes are perfectly correlated. We find that the composition of the latter `functional clusters' is also largely explained in terms of clusters of low degree metabolites in each of these organisms. Our findings mean that most metabolic reactions that are essential can be tagged by one or more low degree metabolites. Those reactions are essential because they are the only ways of producing or consuming their respective tagged metabolites. Furthermore, reactions whose fluxes are strongly correlated can be thought of as `glued together' by these low degree metabolites.Comment: 12 pages main text with 2 figures and 2 tables. 16 pages of Supplementary material. Revised version has title changed and contains study of 3 organisms instead of 1 earlie

Flux-based classification of reactions reveals a functional bow-tie organization of complex metabolic networks

Unraveling the structure of complex biological networks and relating it to their functional role is an important task in systems biology. Here we attempt to characterize the functional organization of the large-scale metabolic networks of three microorganisms. We apply flux balance analysis to study the optimal growth states of these organisms in different environments. By investigating the differential usage of reactions across flux patterns for different environments, we observe a striking bimodal distribution in the activity of reactions. Motivated by this, we propose a simple algorithm to decompose the metabolic network into three sub-networks. It turns out that our reaction classifier which is blind to the biochemical role of pathways leads to three functionally relevant sub-networks that correspond to input, output and intermediate parts of the metabolic network with distinct structural characteristics. Our decomposition method unveils a functional bow-tie organization of metabolic networks that is different from the bow-tie structure determined by graph-theoretic methods that do not incorporate functionality.Comment: 11 pages, 6 figures, 1 tabl

Establishing a diagnostic tool for assessing optimal treatment timing in Indian children with developing malocclusions

Objective: To interrelate chronological age, cervical vertebrae maturational stage and dental calcification stages and to establish latter as first level diagnostic tool to estimate timing of pubertal growth spurt. Materials and Methods: Sample derived from pretreatment panaromic and lateral cephalometric radiographs of patients 8-14 years old. Study sample divided into three groups depending upon Angle’s molar relation: Group I, Group II, Group III. According to chronological age, into: Group A: 8-11 years Group B:11-14 years, further separating males and female subjects in each group. Demirjian et al method was used to assess dental maturity and for skeletal maturity the New Improved Version of Cervical Vertebrae Maturation Method by Baccetti, Franchi and Mc Namara. Statistical analysis was performed using SPSS software package. Chi Square test and Spearman rank-order correlation coefficients measured the association between skeletal maturity indicators and dental calcification stages and statistical significance tested. Results&Conclusions: In females, permanent mandibular second molar Stage E signified circumpubertal phase corresponding with skeletal age CVMS II and for males, it was permanent mandibular first premolar stage E. Early orthodontic interventions for Angle’s Class I and Class II malocclusions should be performed at the circumpubertal period represented by CVMS II in Indian children and for Angle’s Class III malocclusion, facemask therapy beneficial in the prepubertal phase. Females showed higher significant correlation among skeletal and dental calcification stages compared to males

Post endodontic Aspergillosis in an immunocompetent individual

Non-invasive aspergillosis in immunocompetent individuals subsequent to post endodontic treatment can involve the maxillary antrum. An early and accurate diagnosis will aid in prompt and effective treatment. A 35 year old female patient reported with a painful nasomaxillary swelling. Previous records revealed the failure of the endodontic treatment of maxillary left second premolar which was subsequently extracted. Root piece was accidently left behind which resulted in a painful nasomaxillary swelling. The extraction socket was curetted and tissue was sent for histopathological examination, which revealed abundant septate fungal hyphae with numerous spores characteristic of Aspergillus . The patient showed marked improvement in the symptoms with systemic itraconazole at 3 months follow up and complete resolution occurred within 6 months. Inclusion of aspergilloma infections in the differential diagnosis is advocated when patients present with post-endodontic nasomaxillary swellin

Requirement for a Uroplakin 3a-like protein in the development of zebrafish pronephric tubule epithelial cell function, morphogenesis, and polarity

Uroplakin (UP)3a is critical for urinary tract development and function; however, its role in these processes is unknown. We examined the function of the UP3a-like protein Upk3l, which was expressed at the apical surfaces of the epithelial cells that line the pronephric tubules (PTs) of the zebrafish pronephros. Embryos treated with upk3l-targeted morpholinos showed decreased pronephros function, which was attributed to defects in PT epithelial cell morphogenesis and polarization including: loss of an apical brush border and associated phospho-ERM proteins, apical redistribution of the basolateral Na+/K+-ATPase, and altered or diminished expression of the apical polarity complex proteins Prkcz (atypical protein kinase C zeta) and Pard3 (Par3). Upk3l missing its C-terminal cytoplasmic domain or containing mutations in conserved tyrosine or proline residues did not rescue, or only partially rescued the effects of Upk3l depletion. Our studies indicate that Upk3l promotes epithelial polarization and morphogenesis, likely by forming or stimulating interactions with cytoplasmic signaling or polarity proteins, and that defects in this process may underlie the pathology observed in UP3a knockout mice or patients with renal abnormalities that result from altered UP3a expression. © 2012 Mitra et al

Illness narratives of substance users from urban India

Reading Veena Das’s book 'Affliction: Health, Disease, Poverty' was a journey of revelations for me as a health professional. The various dialects of illness that are spoken in the rapidly urbanizing Indian community become coherent, lending a voice to the distinctive sociocultural distress of the men and women who form a part of it. A discussion of the social aspects of illness brings certain questions to mind: Does the medical community fully understand those it tries to help? Is the therapeutic dialogue about the social dimensions of medical problems or vice versa? How do we bridge the mental health gender gap in our societies? To try and find some answers, I present the illness stories of two women who sought treatment at drug abuse treatment clinics in the urban slums of New Delhi. This think piece describes substance use disorder in the context of the cultural processes that have shaped these women, their families, and society

Identification of protein interaction between the Drosophila Runx1 transcription factor Lozenge and ETS-1 factor Pointed using site directed mutagenesis and yeast two-hybrid analysis

Many classes of transcriptional regulatory proteins are known to function in both cell proliferation and differentiation. Runx1 proteins one such family of transcription factors, plays critical roles in hematopoiesis, osteogenesis and leukemogenesis and act as promoter organizers that cooperate with other transcription factors such as Ets-1 in the regulation of gene activation or repression. Genes that are regulated by the Runx1-Ets1 complex, frequently have multiple, adjacent consensus binding sites in their promoters. I have investigated a similar interaction in developing fly eye. Lozenge (DmRunx1) and Pointed P2 (DmEts-1) cooperate to upregulate expression of prospero, which has multiple Lz and Ets binding sites. Prospero protein is essential for establishing R7 cell fate in the developing eye. Site directed mutagenesis and yeast two hybrid assay was employed to assess critical residues involved in the Lz-Pnt P2 interaction. Results unequivocally demonstrate that Lz-Pnt P2 interaction occurs independent of their DNA binding sites, implying that the interaction is not mediated by their mutual interaction with DNA. Site directed mutation reveals reduced Lz-Pnt P2 interaction, indicating the relevance of altered amino acids for the contact between the proteins. Interestingly, akin to AML1 (Runx1), lz is also spliced over the domain important for interaction with Ets-1 proteins. Based on the results obtained in this study, we suggest that splicing produces variants that allow these proteins to either interact with Ets-1 and other proteins to transactivate other genes or to work independently in a divergent role in developmental process