Large-scale purification of halophilic enzymes by salting-out mediated chromatography

Large-scale purification of malate and glutamate dehydrogenases from extremely halophilic bacteria of the Dead Sea based on salting-out mediated chromatography techniques is described. Yields are in the range of hundreds of milligrams. Ammonium sulfate-mediated fractionation of halophilic enzymes on Sepharose is not affected by sodium chloride. The adsorption seems to weaken with increased temperatures. Higher sodium chloride concentrations, in the presence of ammonium sulfate, are necessary to elute halophilic enzymes from DEAE-cellulose as the sulfate concentration is increased. Possible applications of the saltingout mediated chromatography are discussed.     

Bilateral detection thresholds in dextrals and sinistrals reflect the more sensitive side of the nose, which is not lateralized [published erratum appears in Chem Senses 1998 Dec;23(6):761]

Several fundamental questions remain enigmatic concerning human olfactory sensitivity, including (i) whether detection threshold differences exist between the two sides of the nose (and, if so, whether such differences are influenced by handedness) and (ii) whether bilateral (i.e. binasal) stimulation leads to lower thresholds than unilateral stimulation (and, if so, whether the degree of facilitation is inversely related to general olfactory ability). In this study, and well-validated single staircase procedure was used to establish bilateral and unilateral detection thresholds for the cranial nerve I stimulant phenyl ethyl alcohol in 130 right- and 33 left-handed subjects. No differences in sensitivity between the left and right sides of the nose were observed in either group. Bilateral thresholds were lower, on average, than unilateral thresholds when the latter were categorized in terms of left and right nares. However, the bilateral thresholds did not differ significantly from those of the side of the nose with the lower threshold. Overall smell ability, as measured by the University of Pennsylvania Smell Identification Test, did not interact with any of the test measures. These data imply that (i) the left and right sides of the nose do not systematically differ in detection threshold sensitivity for either dextrals or sinistrals and (ii) if central integration of left:right olfactory threshold sensitivity occurs, its effects do not exceed the function of the better side of the nose.      

云南瓶尔小草属一新种

Ophioglossum yongrenense Ching ex Z. R. He et W. M. Chu, sp. nov.Species nova aspectu inter O. kawamuram Tagawa et O. parvum Nishida et Kurita Japonicae, differt a priore frondibus pro parte laminis sterilibus praeditis (in illa frondibus omnino laminis sterilibus non praeditis), a posteriore frondibus pro parte laminis sterilibus non praeditis (in O. parvo Nishida et Kurita frondibus omino laminis sterilibus praeditis).……     

Polypharmacy in the management of patients with schizophrenia on risperidone in a tertiary-care hospital in Malaysia

The present study was conducted primarily to determine the occurrence of polypharmacy in patients with schizophrenia on risperidone. The secondary aim was to ascertain the incidence of inappropriate prescribing with anticholinergics. A retrospective review of the medical records of all patients who were being followed up at the out-patient clinic of a tertiary-care hospital in Malaysia was conducted. Only patients who were being prescribed risperidone between 1 June 2008 and 31 December 2008 were included in the study. Demographic data such as patient’s age, gender and race were obtained from the patient’s medical records. In total, 113 patients met the selection criteria. Polypharmacy was found to occur in 34 patients (30.09%), with the majority (76.47%) being on two antipsychotics. In total, 27 patients (34.18%) on monotherapy with risperidone were prescribed an anticholinergic on scheduled dosing, while 19 patients (24.05%) were prescribed it on an as-needed basis. Of the patients on polypharmacy, 26 (76.47%) were on scheduled dosing of anticholinergics, while three (8.82%) were taking the medication on an as-needed basis. Polypharmacy should be avoided, and the use of anticholinergics should be closely reviewed. By adopting more efficient prescribing practices, costs can be reduced and financial resources can instead be channelled towards more beneficial areas for the patients.     

Tumor-induced osteomalacia: pre- and postoperative biochemical findings

A patient with late-onset hypophosphatemic osteomalacia was treated with oral supplements of phosphate (1.5 g/day) and calcitriol (1.5-3.0 micrograms/day) for 17 months, before a slowly growing tumor in the first metatarsal space became evident. Before treatment concentrations of inorganic phosphate (Pi) and calcitriol in serum and tubular reabsorption of phosphate (TRP) were very low, calcium and parathyroid hormone (PTH) in serum were normal, urinary cyclic adenosine monophosphate (cAMP) was strongly elevated. During the first weeks of conservative treatment urinary cAMP returned to normal; concomitantly there was a transient slight fall in PTH. Serum calcium was in the low normal range and did not significantly change during conservative therapy. During the further course PTH rose to pretreatment values, but urinary cAMP remained normal. When the dose of calcitriol was elevated to 3 x 1.0 micrograms/day, leading to slightly elevated serum concentrations of this substance, Pi in serum rose to the low normal range, but TRP remained low and bone pain, although improved, did not subside. The tumor was locally excised. Postoperatively calcitriol concentration became elevated within 48 hours and remained so for several weeks. The rise in calcitriol concentration preceded the elevation of Pi in serum, not, however, the increase of TRP. The elevation of urinary cyclic AMP before therapy may have been due to a direct action of the substance secreted by the tumor.     

Molecular Toolbox for Genetic Manipulation of the Stalked Budding Bacterium Hyphomonas neptunium

The alphaproteobacterium Hyphomonas neptunium proliferates by a unique budding mechanism in which daughter cells emerge from the end of a stalk-like extension emanating from the mother cell body. Studies of this species so far have been hampered by the lack of a genetic system and of molecular tools allowing the regulated expression of target genes. Based on microarray analyses, this work identifies two H. neptunium promoters that are activated specifically by copper and zinc. Functional analyses show that they have low basal activity and a high dynamic range, meeting the requirements for use as a multipurpose expression system. To facilitate their application, the two promoters were incorporated into a set of integrative plasmids, featuring a choice of two different selection markers and various fluorescent protein genes. These constructs enable the straightforward generation and heavy metal-inducible synthesis of fluorescent protein fusions in H. neptunium, thereby opening the door to an in-depth analysis of polar growth and development in this species.