Diversity and impacts of macroalgae and cyanobacteria on multi-stressed coral reefs in the Gulf of Mannar Marine Biosphere Reserve.

In India, intertidal seaweed resources are widely investigated and utilized for various applications, whereas reef-associated seaweed resources and their impacts on corals are lesser known. Thus, the present study investigated the diversity and impacts of macroalgae and cyanobacteria on coral reefs distributed in 21 islands under the Gulf of Mannar Marine Biosphere Reserve (GoMMBR), Tamil Nadu. About 140 macroalgal species representing 53 species of Chlorophyta, 32 species of Ochrophyta (Phaeophyta), and 55 species of Rhodophyta were recorded. Only three cyanobacterial species were documented during this study. All the documented species were categorized as edible, medicinal, smothering, bloom-forming, sediment trapping, and auxiliary. Diversity indices and multivariate analysis indicated latitudinal gradient distribution of macroalgae, where the maximum diversity was observed from the Mandapam group of Islands. The predominant genera observed in all the islands were Caulerpa, Halimeda, Turbinaria, and Sargassum. The updated checklist of seaweeds and cyanobacteria of India revealed 1118 and 258 species, correspondingly, on Indian coasts, including coral reef regions. The use of traditional morphology-based techniques in this study without molecular approaches to identify all of the specimens limits our investigation. Thus, molecular taxonomy is necessary to revalidate and confirm the actual genetic diversity existing in the Indian waters. Results of this study would benefit the scientific community and industries in various aspects, such as molecular taxonomy, biomass utilization, reef conservation, and industrial applications.

Disability and quality of life in patients with treatment-resistant schizophrenia on long- term clozapine therapy.

Objectives: To assess disability and quality of life (QOL) in treatment resistant schizophrenia (TRS) on long term clozapine therapy and assess their correlation with positive, negative and cognitive symptoms. Methodology: Disability and QOL in forty patients with TRS (as per modified Kane's criteria) were assessed using World Health Organization Disability Assessment Schedule 2.0 and World Health Organization Quality of Life-BREF. Scale for assessment of positive symptoms, scale for assessment of negative symptoms and Addenbrooke's cognitive examination-III were used to assess positive, negative and cognitive symptoms. Medication adherence rating scale assessed medication adherence. Results: Disability and QOL correlated significantly with medication adherence, negative and cognitive symptoms but not with positive symptoms. Subgroup analysis revealed significant difference between medication adherence (good vs poor) and cognitive (impairment vs non-impairment) groups. Conclusion: Negative and cognitive symptoms, and medication adherence correlated with disability and QOL.

Unilateral buried optic nerve head drusen triggering central retinal vein occlusion in young - Discovering an eclipsed entity.

Optic nerve head (ONH) drusen are acellular calcified concretions. Buried drusen manifests as pseudopapilledema. The compressive effects of ONH drusen can rarely precipitate central retinal vein occlusion (CRVO). The superimposition of pseudopapilledema on disc edema in CRVO poses a diagnostic dilemma. A 40-year-old female without systemic comorbidities presented with resolving CRVO. An exhaustive systemic workup revealed no abnormalities. Ultrasonography demonstrated buried ONH drusen. This unusual etiology must be considered in a young patient in the absence of systemic risk factors, persistence of "nasally conspicuous" disc elevation, and presence of peripapillary hemorrhages. Ultrasonography must be incorporated in the diagnostic armamentarium in a young patient with CRVO.

Metabolic syndrome in schizophrenia: Differences between antipsychotic-naïve and treated patients.

Metabolic syndrome (MetS) has been recognized as a risk factor for cardiovascular morbidity and mortality in general population and in patients with severe mental illnesses like schizophrenia. This paper reviews studies on MetS in schizophrenia and related psychotic disorders, and assesses the contribution of antipsychotics toward the development of MetS. Databases of Medline (PubMed), PsycINFO, and Scopus were searched for MetS, psychotic disorders, and antipsychotic drugs from inception till present. Prevalence of MetS in patients with schizophrenia was found to be ranging from 3.3% to 68.0%. Prevalence in antipsychotic-naïve and antipsychotic-treated patients ranged between 3.3-26.0% and 32.0-68.0% respectively, and was higher in younger patients, female gender and Hispanics, and lower in African-Americans and Orientals. Prevalence of metabolic abnormalities was higher in patients receiving second generation antipsychotics (SGAs), especially with clozapine, olanzapine, and risperidone, as compared to first generation antipsychotics (FGAs). Antipsychotic-induced changes on metabolic indices became evident after 2 weeks and reached maximum at 3 months of treatment. There is a need to sensitize the mental health professionals at all levels about the need of screening and monitoring for MetS in patients receiving antipsychotics.

Primary cement spacers: a cost-effective, durable limb salvage option for knee tumors.

Of a total of 818 limb sparing resections in the lower limb requiring reconstruction between December 2002 and April 2010 at our centre, primary cement spacers were used in 15 cases. In three cases they were used as joint sparing intercalary reconstructions and in 12 cases knee arthrodesis was done. Implants used to provide stability to the construct included stacked intramedullary Kuntscher nails in four, an interlocking nail in one, plates in two and a combination of nail with plate in eight. Mean length of bone resected was 18 cm. Mean follow-up was 26 months (10-87 months). There were no local recurrences and none of the spacers needed revision for mechanical failure. The Musculoskeletal Tumor Society score for patients ranged from 20 to 29 with a mean of 24 (80%). Patients with intercalary resection had better functional scores than those with arthrodesis. The construct was successfully revised to a vascularised fibula arthrodesis or prosthesis with good eventual function in three cases. Cement spacers are a suitable cost-effective, durable reconstruction modality in selected patients with good functional outcomes. They are an option to amputation in patients with financial constraints and those that present with large volume or infected fungating tumors.

Peyer's patches are precocious to the appendix in human development.

PP are first visible at approximately 15.5 wk gestation after which there is a rapid spurt in the development and maturation of lymphoid follicles so that at any given point of time new foci of PP development are continuously formed at a rapid rate. Addition of rows of follicles results in the formation of a PP. Immature PP of younger fetuses have a spongy structure in contrast with the compact lymphoid follicles of mature PP of older fetuses. Immunocytochemical studies reveal that there is a subtle gradation in the expression of lymphocyte surface markers with increasing fetal age. Expression of antigenic markers occurs in an ordered sequence viz. HLA - DR, CD19 (B cell population), CD9 (pre-B cells), CD3 T lymphocytes, CD4 helper / inducer lymphocytes, the CD8 suppressor / cytotoxic cells and lastly, the CD57 Natural Killer cells. The antigens are expressed first on lymphocytes of PP and thereafter in those of the appendix. Our findings clearly demonstrate that the approximately 5 wk fetal period from 17.5 wk to 22 wk represents a major growth phase in the development of surface markers of lymphocytes in the mucosal immune system of the gut.

Sodium-calcium exchanger is initially expressed in a heart-restricted pattern within the early mouse embryo.

Although the sodium-calcium exchanger (NCX1) is encoded by a single gene, it is widely expressed in both fetal and adult tissues and functions in many diverse physiological processes to maintain intracellular calcium homeostasis. In order to determine whether NCX1 is also ubiquitously expressed in the early mouse embryo, in situ hybridization and RT-PCR were used to determine the spacio-temporal expression of NCX1. Our results indicate that NCX1 expression is present within the 7.75-8.0 dpc cardiogenic plate before the first heartbeat, and that NCX1 is initially expressed in a heart-restricted pattern within the early mouse embryo. However, in more developed embryos (11.0 dpc and older) NCX1 is expressed in other tissues.

Structural organization and promoter analysis of murine heat shock transcription factor-1 gene.

Heat shock factor-1 (HSF-1) activates transcription of heat shock proteins in eukaryotes. Several overlapping genomic clones containing the murine HSF-1 gene were isolated from a phage genomic library. Results indicate that the HSF-1 gene contains 13 exons that span at least 30 kilobase pairs. Sequence analysis of the 5'-untranslated region of HSF-1 suggests that it contains sequences of a recently described Bop1 gene in reverse orientation within its first 331 base pairs (bp) upstream of the translation initiation site. The minimal promoter sequence required for HSF-1 basal expression was identified by deletion analysis from -4 kilobase pairs to -331 bp of the promoter fused to a luciferase reporter gene using transient transfection assays. Results indicate that 331 bp upstream of the HSF-1 translation start site is required for maximal basal expression in NIH3T3 and F9 cells. This fragment also results in high levels of luciferase activity in the reverse orientation, that is, 5' to the Bop1 gene, suggesting that this segment is bidirectional and could be utilized for basal expression of both HSF-1 and Bop1 genes. This segment of the promoter contains recognition elements for Sp1 and CCAAT-box binding transcription factors, which when mutated in either sense or antisense orientations to the HSF-1 gene results in a reduction of basal expression by 50-75% relative to wild type, suggesting that these sites are critical for basal expression of both HSF-1 and Bop1 genes.

The catalytic mechanism of kynureninase from Pseudomonas fluorescens: evidence for transient quinonoid and ketimine intermediates from rapid-scanning stopped-flow spectrophotometry.

The reaction of Pseudomonas fluorescens kynureninase with L-kynurenine and L-alanine has been examined using rapid-scanning stopped-flow spectrophotometry. Mixing kynureninase with 0.5 mM L-kynurenine results in formation of a quinonoid intermediate, with lambdamax = 494 nm, within the dead time (ca. 2 ms) of the stopped-flow mixer. This intermediate then decays rapidly, with k = 743 s-1, and this rate constant is reduced to 347 s-1 in [2H]H2O, suggesting that protonation of this intermediate by a solvent exchangeable proton takes place. Rapid quench experiments demonstrate that covalent changes in the cofactor occur, as pyridoxal 5'-phosphate is converted to pyridoxamine 5'-phosphate in about 30 mol % within 5 ms after mixing. Under single turnover conditions in the reaction of kynureninase with l-kynurenine, a transient shoulder absorbing at 335 nm is observed that may be a pyruvate ketimine intermediate. In contrast, the reaction of kynureninase with 0.5 mM l-kynurenine in the presence of 10 mM benzaldehyde results in the formation of a quinonoid intermediate (k = 67.4 s-1) with a very strong absorbance peak at 496 nm. The reaction of L-alanine with kynureninase exhibits the rapid formation (386 s-1 at 0.1 M) of an external aldimine intermediate absorbing at 420 nm, followed by slower formation of a quinonoid intermediate with a peak at 500 nm (k = 2.5 s-1). The 420 nm peak then decays slowly with concomitant formation of a peak at 320 nm corresponding to a pyruvate ketimine. These data demonstrate that quinonoid and ketimine intermediates are catalytically competent in the reaction mechanism of kynureninase, and provide additional support for our proposed mechanism for kynureninase from steady-state kinetic studies [Koushik, S. V., Sundararaju, B., and Phillips, R. S. Biochemistry 1998, 37, 1376-1382].

The catalytic mechanism of kynureninase from Pseudomonas fluorescens: insights from the effects of pH and isotopic substitution on steady-state and pre-steady-state kinetics.

The effects of pH and isotopic substitution of substrate and solvent on the reaction of kynureninase from Pseudomonas fluorescens have been determined. The pH dependence of kcat/Km for L-kynurenine is bell-shaped, with apparent pKa's of 6.25 +/- 0.05 on the acidic limb and 8.9 +/- 0.1 on the basic limb, and with a pH-dependent value of kcat/Km of 2 x 10(5) M-1 s-1. The pH dependence of kcat/Km for 3-hydroxykynurenine is also bell-shaped, with apparent pKa's of 6.49 +/- 0.07 and 8.55 +/- 0.09, and with a pH-dependent value of 2.5 x 10(3) M-1 s-1. The kcat for L-kynurenine decreases at acidic pH values, with an apparent pKa of 6.43 +/- 0.06 and a pH-dependent value of 7 s-1. The solvent kinetic isotope effect on kcat for the reaction of kynurenine in [2H]H2O is 6.56 +/- 0.59, whereas there is no normal kinetic isotope effect on kcat/Km, at pH 8.1. The proton inventory of kcat fits very well to the Gross-Butler equation, with x = 0.825 +/- 0.08, suggesting that only a single proton is transferred in the rate-determining step. In contrast, there is no significant kinetic isotope effect on either kcat or kcat/Km with alpha-[2H]-L-kynurenine as the substrate. There is a "burst" of anthranilate (0.7 mol/mol of enzyme) formed in the pre steady state of the reaction of kynureninase, with a rate constant of 54 s-1 which is not affected by [2H]H2O. The partition ratio of alanine to pyruvate formation is 2.3 x 10(4) in H2O and 6.9 x 10(3) in [2H]H2O. Taken together, these data indicate that the rate-limiting step in the reaction of kynureninase occurs subsequent to the first irreversible step, which is anthranilate release, is general base catalyzed, and involves transfer of only a single proton. On the basis of these observations, we propose that the rate-limiting step in the reaction of kynureninase is C-4' deprotonation of the pyruvate pyridoxamine 5'-phosphate ketimine intermediate.

Cloning, sequence, and expression of kynureninase from Pseudomonas fluorescens.

We have cloned the gene encoding kynureninase from Pseudomonas fluorescens using a restriction site polymerase chain reaction technique (RS-PCR) (G. Sarkar, R. T. Turner, and M. E. Bolander PCR Methods Appl. 2, 318-322, 1993) and expressed the enzyme in Escherichia coli DH5a F'. The kynureninase gene has an open reading frame (ORF) of 1251 base pairs that codes for a protein of 416 amino acids with a calculated molecular weight of 45,906. The protein purified from P. fluorescens has N-terminal threonine and an observed molecular weight of 45,787 by electrospray mass spectrometry, suggesting that the N-terminal methionine is removed by posttranslational processing. The complete gene was obtained by PCR and inserted into pTZ18U. The resultant plasmid was used to transform E. coli DH5alpha F', and these cells overexpressed kynureninase to about 37% of total soluble protein. The isolated recombinant protein has molecular weight and Km values identical to those of the native protein from P. fluorescens. The amino acid sequence exhibits 29% identity with those of rat and human kynureninases and 32% identity with the amino acid sequence translated from a Saccharomyces cerevisiae ORF. Alignment of the four sequences shows a highly conserved region which corresponds to the pyridoxal-5'-phosphate (PLP) binding site of rat kynureninase. Based on this alignment, we predict that Lys227 and Asp212 in P. fluorescens kynureninase are involved in pyridoxal-5'-phosphate binding. P. fluorescens kynureninase also exhibits significant homology to the nifS gene product, cysteine desulfurase, and to eucaryotic serine/pyruvate aminotransferases, suggesting that it is a member of subgroup IV of the aminotransferase family of PLP-dependent enzymes.