Life-history ofNeurospora intermedia in a sugar cane field

The life-history ofNeurospora in nature has remained largely unknown. The present study attempts to remedy this. The following conclusions are based on observation ofNeurospora on fire-scorched sugar cane in agricultural fields, and reconstruction experiments using a colour mutant to inoculate sugar cane burned in the laboratory. The fungus persists in soil as heat- resistant dormant ascospores. These are activated by a chemical(s) released into soil from the burnt substrate. The chief diffusible activator of ascospores is furfural and the germinating ascospores infect the scorched substrate. An invasive mycelium grows progressively upwards inside the juicy sugar cane and produces copious macroconidia externally through fire- induced openings formed in the plant tissue, or by the mechanical rupturing of the plant epidermal tissue by the mass of mycelium. The loose conidia are dispersed by wind and/or foraged by microfauna. It is suggested that the constant production of macroconidia, and their ready dispersal, serve a physiological role: to drain the substrate of minerals and soluble sugars, thereby creating nutritional conditions which stimulate sexual reproduction by the fungus. Sexual reproduction in the sugar- depleted cellulosic substrate occurs after macroconidiation has ceased totally and is favoured by the humid conditions prevailing during the monsoon rains. Profuse micro-conidiophores and protoperithecia are produced simultaneously in the pockets below the loosened epidermal tissue. Presumably protoperithecia are fertilized by microconidia which are possibly transmitted by nematodes active in the dead plant tissue. Mature perithecia release ascospores in situ which are passively liberated in the soil by the disintegration of the plant material and are, apparently, distributed by rain or irrigation water.     

Sexual differentiation of brain and behavior in the zebra finch: Critical periods for effects of early estrogen treatment

In order to determine the critical period(s) during which estrogen alters sexually dimorphic behavior and neuroanatomy in zebra finches (Poephila guttata), nestlings were injected daily 20 μg estradiol benzoate (EB) during posthatching week 1, week 2, week 3, or weeks 1, 2, and 3. At 7 months of age, birds were implanted with testosterone propionate and tested with female partners for singing, dancing, and copulatory mounting. Brains were subsequently processed for morphometry, and the volumes of the song system nuclei HVC, area X, and RA and the soma sizes and densities of neurons in RA were determined. Males given EB during week 1 failed to mount. Females given EB during week 1 were fully masculinized with respect to dancing and RA neuron soma size and density, and were partially masculinized with respect to song nuclei volumes and singing. Treatment beginning after week 1 was ineffective or less effective for all measures. Only for RA neuron measures was treatment for all three weeks more effective than week 1 treatment. Thus the first post-hatching week is the most influential period of those tested for effects of exogenous estrogen on sexual differentiation in this species, and is a period during which both masculinization of females and demasculinization of males is possible. 1994 John Wiley & Sons, Inc.     

In Vitro,In Silico,ADME and Theoretical Analysis of Mn(II) and Co(II) Complexes Derived from Methyl-(Z)-N′-Carbamothioylcarbamohydrazonate Schiff Base Ligand

Mn(II) and Co(II) complexes of methyl-(Z)−N′-carbamothioylcarbamohydrazonate Schiff base ligand were synthesized. The ligand and metal salts were taken in 2 : 1 stoichiometric ratio. All the synthesized complexes were characterized using elemental analysis, molar conductance, magnetic moment and various spectroscopic techniques (FT-IR, UV/VIS, EPR) techniques. Elemental and spectroscopic results verified bidentate donor nature of the ligand and octahedral geometry of all the complexes. The non-electrolytic nature of Mn(II) and Co(II) complexes were suggested by conductivity data analysis. In vitro antibacterial (E. coli and S. aureus) and antifungal (C. albicans and C. tropicalis) screening were achieved by employing agar well diffusion method which revealed better antimicrobial activity of Co(II) complexes than Mn(II) complexes. In silico SwissADME study predicted the drug-likeness probability of ligand and complexes. The interaction of two bacterial proteins (E. coli and S. aureus) with compounds was also analyzed using molecular docking study, which corroborate the in vitro analysis.     

Fungal spores are an important component of library air

The airborne fungal spore types were studied in different libraries in Delhi, using an Andersen sampler and a Burkard personal sampler, for culturable and non-culturable fungi respectively. The concentration inside the libraries, before and after the agitation of books, were compared with outside air. The major contributors to the library air areCladosporium, aspergilli/penicillia, smuts andAlternaria, varying from 50 to 14%. Some fungi (Cladosporium, Alternaria, smut,Penicillium chrysogenum andnigricans) showed seasonal occurrence, corresponding to their occurrence in the extramural environment. Aspergilli/penicillia,Drechslera, Curvularia andAspergillus flavus had a significantly higher concentration (P<0.01) inside the library, and recorded a significant increase in concentration after agitation of books. Air-conditioned libraries have low fungal spore concentrations, as compared to naturally ventilated libraries.     

Validity and Reliability of Using a Self-Lavaging Device for Cytology and HPV Testing for Cervical Cancer Screening: Findings from a Pilot Study

Self-sampling could increase cervical cancer screening uptake. While methods have been identified for human papillomavirus (HPV) testing, to date, self-sampling has not provided adequate specimens for cytology. We piloted the validity and reliability of using a self-lavaging device for cervical cytology and HPV testing. We enrolled 198 women in New York City in 2008–2009 from three ambulatory clinics where they received cervical cancer screening. All were asked to use the Delphi Screener™ to self-lavage 1–3 months after clinician-collected index cytological smear (100 normal; 98 abnormal). Women with abnormal cytology results from either specimen underwent colposcopy; 10 women with normal results from both specimens also underwent colposcopy. We calculated sensitivity of self-collected cytology to detect histologically confirmed high grade lesions (cervical intraepithelial neoplasia, CIN, 2+); specificity for histology-negative (CIN 1 or lower), paired cytology negative, or a third cytology negative; and kappa for paired results. One hundred and ninety-seven (99.5%) women self-collected a lavage. Seventy-five percent had moderate to excellent cellularity, two specimens were unsatisfactory for cytology. Seven of 167 (4%) women with definitive results had CIN2+; one had normal and six abnormal cytology results with the self-lavage (sensitivity = 86%, 95% Confidence Interval, CI: 42, 100). The kappa for paired cytology was low (0.36; 95% CI: 0.25, 0.47) primarily due to clinician specimens with atypical squamous cells of undetermined significance (ASC-US) and low grade squamous intraepithelial lesion (LSIL) coded as normal using Screener specimens. However, three cases of HSIL were coded as ASC-US and one as normal using Screener specimens. Seventy-three women had paired high-risk HPV tests with a kappa of 0.66 (95% CI: 0.49, 0.84). Based on these preliminary findings, a larger study to estimate the performance of the Screener for co-testing cytology and HPV or for HPV testing with cytology triage is warranted.

Trial Registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00702208","term_id":"NCT00702208"}}NCT00702208     

Monomerization alters the dynamics of the lid region in Campylobacter jejuni CstII: an MD simulation study

CstII, a bifunctional (α2,3/8) sialyltransferase from Campylobacter jejuni, is a homotetramer. It has been reported that mutation of the interface residues Phe121 (F121D) or Tyr125 (Y125Q) leads to monomerization and partial loss of enzyme activity, without any change in the secondary or tertiary structures. MD simulations of both tetramer and monomer, with and without bound donor substrate, were performed for the two mutants and WT to understand the reasons for partial loss of activity due to monomerization since the active site is located within each monomer. RMSF values were found to correlate with the crystallographic B-factor values indicating that the simulations are able to capture the flexibility of the molecule effectively. There were no gross changes in either the secondary or tertiary structure of the proteins during MD simulations. However, interface is destabilized by the mutations, and more importantly the flexibility of the lid region (Gly152-Lys190) is affected. The lid region accesses three major conformations named as open, intermediate, and closed conformations. In both Y121Q and F121D mutants, the closed conformation is accessed predominantly. In this conformation, the catalytic base His188 is also displaced. Normal mode analysis also revealed differences in the lid movement in tetramer and monomer. This provides a possible explanation for the partial loss of enzyme activity in both interface mutants. The lid region controls the traffic of substrates and products in and out of the active site, and the dynamics of this region is regulated by tetramerization. Thus, this study provides valuable insights into the role of loop dynamics in enzyme activity of CstII.     

Differential regulation of cholesterol homeostasis in transgenic mice expressing human cholesterol ester transfer protein

We investigated whether expression of cholesterol ester transfer protein (CETP) in mice alters the regulation of cholesterol metabolism. Transgenic mice expressing human CETP (CETP-TG) and nontransgenic littermates (non-TG) were fed either a monounsaturated fatty acid (MUFA) or a saturated fatty acid (SFA)-rich diet in the presence or absence of cholesterol. Mice fed with MUFA diet had higher CETP activity compared with SFA-fed mice. Addition of cholesterol to the MUFA diet decreased CETP activity, whereas addition of cholesterol to the SFA diet had no effect. Cholesterol 7alpha-hydroxylase (Cyp7a) activity was higher in CETP-TG mice compared with non-TG mice when fed a MUFA diet, whereas SFA fed CETP-TG mice showed lower Cyp7a activity as compared with non-TG. Microsomal triglyceride transfer protein (MTTP) activity was higher in CETP-TG mice compared with non-TG mice when fed a MUFA diet. HMG-CoA reductase activity was lower in CETP-TG mice compared with non-TG mice when fed a MUFA or a SFA diet. These data demonstrate that the regulation of Cyp7a, HMG-CoA reductase, and MTTP is altered in CETP-TG mice as compared with non-TG mice and these alterations are further modulated by the quality of dietary fats. These findings highlight the importance of CETP in regulating cholesterol homeostasis.