The Houses That Matsutake Built<Superscript>1</Superscript>

The Houses That Matsutake Built. In the mountains of northwest Yunnan, China, a valuable mushroom, matsutake or song rong (Tricholoma matsutake) was commodified in the 1980s. Since that time, it has been exported in large quantities to Japan. The sale of matsutake now contributes more to the income of Shangri-la County (Diqing Autonomous Tibetan Prefecture) than any other crop, including timber and livestock. During the 1980s and 1990s, villagers in this remote region used their mushroom earnings to build spacious, beautiful new houses in the traditional local (Kham) style, and in some cases to buy motor vehicles or open businesses. In villages with access to productive matsutake habitat, virtually every household was able to build a new house; entire villages were transformed. During the 1990s, several villages developed locally based management regimes to enhance production and to address the problems and conflicts that arose from the harvest of such a valuable product. More recently, government agencies and NGOs have played a highly visible role in promoting “sustainable” harvest policies. The implications of their involvement are briefly examined and the future of matsutake harvest in Yunnan is discussed.     

Soluble Guanylate Cyclase α1–Deficient Mice: A Novel Murine Model for Primary Open Angle Glaucoma

Primary open angle glaucoma (POAG) is a leading cause of blindness worldwide. The molecular signaling involved in the pathogenesis of POAG remains unknown. Here, we report that mice lacking the α₁ subunit of the nitric oxide receptor soluble guanylate cyclase represent a novel and translatable animal model of POAG, characterized by thinning of the retinal nerve fiber layer and loss of optic nerve axons in the context of an open iridocorneal angle. The optic neuropathy associated with soluble guanylate cyclase α₁–deficiency was accompanied by modestly increased intraocular pressure and retinal vascular dysfunction. Moreover, data from a candidate gene association study suggests that a variant in the locus containing the genes encoding for the α₁ and β₁ subunits of soluble guanylate cyclase is associated with POAG in patients presenting with initial paracentral vision loss, a disease subtype thought to be associated with vascular dysregulation. These findings provide new insights into the pathogenesis and genetics of POAG and suggest new therapeutic strategies for POAG.     

Screening for MCL-PHA-Producing Fluorescent Pseudomonads and Comparison of MCL-PHA Production Under Iso-osmotic Conditions Induced by PEG and NaCl

The medium chain length polyhydroxyalkanoates (MCL-PHA) have attracted much attention from academic and industrial communities for their interesting applications in medical field. The aim of this study was to screen high MCL-PHA-producing fluorescent pseudomonads, and to compare the effect of osmotic stress generated by NaCl (ionic) and polyethylene glycol (PEG, non-ionic inert polymer) on PHA production. A total of 50 fluorescent pseudomonads isolated from rhizospheric soil were screened for PHA production by Sudan Black staining. Out of all the PHA-producing isolates only five were MCL-PHA producers as detected by MCL-PCR. Isolate Bar1 identified as Pseudomonas fluorescens by 16S rRNA gene sequencing was selected for further analysis due to its high MCL-PHA production ability. The iso-osmotic stress generated by NaCl and PEG-6000 showed 5.75- and 3.19-fold enhanced production of PHA at ?2 bar osmotic potential, over control (0 bar), respectively. There was 1.8-fold enhanced production of PHA at ?2 bar osmotic stress induced by NaCl over PEG. PEG reduces availability of water to microorganisms without reducing exogenously provided nutrients which appear to be responsible for its down performance over NaCl. The FTIR analysis of PHA sample purified from cells showed strong marker bands near 1742, 2870, 1170, 1099, and 2926 cm^?1, corresponding to MCL-PHA. The study reported that supplementation of NaCl (electrolyte) in growth media enhances the production of MCL-PHA which can be very useful for its industrial production.     

Titanium Dioxide Nanoparticles As Guardian against Environmental Carcinogen Benzo[alpha]Pyrene

Polycyclic aromatic hydrocarbons (PAH), like Benzo[alpha]Pyrene (BaP) are known to cause a number of toxic manifestations including lung cancer. As Titanium dioxide Nanoparticles (TiO₂ NPs) have recently been shown to adsorb a number of PAHs from soil and water, we investigated whether TiO₂ NPs could provide protection against the BaP induced toxicity in biological system. A549 cells when co-exposed with BaP (25 µM, 50 µM and 75 µM) along with 0.1 µg/ml,0.5 µg/ml and 1 µg/ml of TiO₂ NPs, showed significant reduction in the toxic effects of BaP, as measured by Micronucleus Assay, MTT Assay and ROS Assay. In order to explore the mechanism of protection by TiO₂ NP against BaP, we performed in silico studies. BaP and other PAHs are known to enter the cell via aromatic hydrocarbon receptor (AHR). TiO₂ NP showed a much higher docking score with AHR (12074) as compared to the docking score of BaP with AHR (4600). This indicates a preferential binding of TiO₂ NP with the AHR, in case if both the TiO₂ NP and BaP are present. Further, we have done the docking of BaP with the TiO₂ NP bound AHR-complex (score 4710), and observed that BaP showed strong adsorption on TiO₂ NP itself, and not at its original binding site (at AHR). TiO₂ NPs thereby prevent the entry of BaP in to the cell via AHR and hence protect cells against the deleterious effects induced by BaP.     

The comparative effects of metals on the hatching of earthworm cocoons

To establish the use of Metaphire posthuma as a sensitive model for ecotoxicological studies, the comparative effects of five metals on the hatching profiles of the cocoons of the earthworms, Metaphire posthuma, Eisenia foetida and Perionyx excavatus, were studied. The cocoons of the three species of earthworms were exposed to copper, chromium (III), chromium (VI), lead and zinc at 1.25, 2.5, 5.0 and 10.0 ppm. Viable cocoons were incubated at 20 +/- degrees C by using the immersion method. The results indicated that the inhibition of cocoon hatching was concentration dependent. The normal hatching, delayed hatching and non-viability of cocoons were recorded. At a concentration of 1.25 ppm, there was almost no effect on the hatching of the cocoons of all three species of earthworms, except when exposed to chromium (VI), but higher concentrations (2.5 and 5.0 ppm) caused severe effects. It was concluded that M. posthuma was more sensitive than the other two species, and that it is a suitable model for use in ecotoxicity testing.