High-dose zolpidem abuse in a patient with insomnia comorbid with major depressive disorder

Sleep and Biological Rhythms - A 39-year-old married woman was referred to a psychiatry outpatient clinic for treatment of major depressive disorder (MDD). The dose of zolpidem she had been taking...     

Factors influencing the habitat choice of pangolins (Manis spp.) in low land of Nepal

Pangolins in the genus Manis are nocturnal, burrowing, insectivorous mammals listed as Critically Endangered or Endangered by the International Union for Conservation of Nature. Two species of pangolins are found in Nepal: the Chinese pangolin (Manis pentadactyla) and Indian pangolin (Manis crassicaudata). Despite having high conservation priority, little attention has been given to conservation interventions of both species of pangolins found in the Terai region (low land) of Nepal. The present study assesses habitat use and factors affecting the habitat choice of pangolins in low land (Terai), Nepal, focusing on Amritdharapani Community Forest of Chitwan district. Pangolin burrows were used as the indirect signs, and opportunistic sampling method was used to record the burrows. After the identification of all occurrence sites (burrows) in the field, random points were generated excluding the points where burrows were recorded for sampling of nonoccurrence sites. A total of thirty‐nine burrows were observed at elevations ranging from 301 to 413 masl. Burrows were frequently associated with northwest aspects, gentle slope (15°–20°), moderate canopy cover (51%–75%), red‐colored soil, and acidic soils with pH 6.5–7. The burrows were most common in areas with weak human disturbance (i.e., 1,500–1,700 m from settlements), 800–1,200 m from roads, and within 300 m from a water source and within 20 m from the nearest termitarium. Distance to settlement, distance to road, soil pH, and canopy cover were found to affect the habitat choice of pangolins in the study area.     

Effect of different biosynthetic precursors on the production of nargenicin A1 from metabolically engineered Nocardia sp. CS682

Nargenicin A1 is a 28-membered polyketide macrolide, with antibacterial activity against methicillin-resistant Staphylococcus aureus, produced by Nocardia sp. CS682. In this study, the production of nargenicin A1 was improved by enhancing the supply of different biosynthetic precursors. In Nocardia sp. CS682 (KCTC11297BP), this improvement was ~4.62-fold with the supplementation of 30 mM methyl oleate, 4.25-fold with supplementation of 15 mM sodium propionate, and 2.81-fold with supplementation of 15 mM sodium acetate. In Nocardia sp. metK18 and Nocardia sp. CS682 expressing S-adenosylmethionine synthetase (MetK), the production of nargenicin A1 was improved by ~5.57-fold by supplementation with 30 mM methyl oleate, 5.01-fold by supplementation with 15 mM sodium propionate, and 3.64-fold by supplementation with 15 mM sodium acetate. Furthermore, supplementing the culture broth of Nocardia sp. ACC18 and Nocardia sp. CS682 expressing the acetyl-CoA carboxylase complex (AccA2 and AccBE) with 30 mM methyl oleate, 15 mM sodium propionate, or 15 mM sodium acetate resulted in ~6.99-, 6.46-, and 5.58-fold increases, respectively, in nargenicin A1 production. Our overall results showed that among the supplements, methyl oleate was the most effective precursor supporting the highest titers of nargenicin A1 in Nocardia sp. CS682, Nocardia sp. metK18, and Nocardia sp. ACC18.     

Biosynthesis of the nargenicin A<Subscript>1</Subscript> pyrrole moiety from <Emphasis Type="Italic">Nocardia</Emphasis> sp. CS682

A number of structurally diverse natural products harboring pyrrole moieties possess a wide range of biological activities. Studies on biosynthesis of pyrrole ring have shown that pyrrole moieties are derived from l-proline. Nargenicin A₁, a saturated alicyclic polyketide from Nocardia sp. CS682, is a pyrrole-2-carboxylate ester of nodusmicin. We cloned and identified a set of four genes from Nocardia sp. CS682 that show sequence similarity to the respective genes involved in the biosynthesis of the pyrrole moieties of pyoluteorin in Pseudomonas fluorescens, clorobiocin in Streptomyces roseochromogenes subsp. Oscitans, coumermycin A₁ in Streptomyces rishiriensis, one of the pyrrole rings of undecylprodigiosin in Streptomyces coelicolor, and leupyrrins in Sorangium cellulosum. These genes were designated as ngnN4, ngnN5, ngnN3, and ngnN2. In this study, we presented the evidences that the pyrrole moiety of nargenicin A₁ was also derived from l-proline by the coordinated action of three proteins, NgnN4 (proline adenyltransferase), NgnN5 (proline carrier protein), and NgnN3 (flavine-dependent acyl-coenzyme A dehydrogenases). Biosynthesis of pyrrole moiety in nargenicin A₁ is initiated by NgnN4 that catalyzes ATP-dependent activation of l-proline into l-prolyl-AMP, and the latter is transferred to NgnN5 to create prolyl-S-peptidyl carrier protein (PCP). Later, NgnN3 catalyzes the two-step oxidation of prolyl-S-PCP into pyrrole-2-carboxylate. Thus, this study presents another example of a pyrrole moiety biosynthetic pathway that uses a set of three genes to convert l-proline into pyrrole-2-carboxylic acid moiety.     

Structural studies on IgG oligosaccharides of patients with primary Sjögren's syndrome

Sjögren's syndrome (SS) is an autoimmune disease, and some patients have been found to have SS complicated with rheumatoid arthritis (RA), in which IgG is known to carry abnormal N-linked oligosaccharides. In order to investigate the relationship between SS and RA, the structures of N-linked oligosaccharides of IgG from 12 primary SS patients without RA, 9 RA patients, and 8 healthy individuals were analyzed using reversed-phase high-performance liquid chromatography, in combination with sequential exoglycosidase treatment and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. All of the IgG samples obtained from primary SS patients, RA patients, and healthy individuals contained the same series of biantennary complex-type oligosaccharides, but the ratio of each oligosaccharide differed among these 3 groups. The incidence of galactose-lacking N-linked oligosaccharides obtained from the IgG of RA patients was significantly higher than that from healthy individuals, but that from the serum IgG of primary SS patients varied among individuals. The patients with primary SS were classified into two groups based on the galactosylation levels of IgG oligosaccharides; one group exhibits galactosylation levels as low as those of RA patients and another exhibits levels similar to those of healthy individuals. Measurement of levels of rheumatoid factor (RF) revealed that primary SS patients with a high incidence of RF belonged to the low galactosylation group, as did RA patients. These results suggest that appearance of IgG carrying abnormal N-linked oligosaccharides in primary SS may be related to future complication with RA.     

COVID‐19 lockdown frees wildlife to roam but increases poaching threats in Nepal

To contain transmission of COVID‐19, lockdowns or strict restrictions of people''s mobility outside their residences were instituted in a majority of countries worldwide, including Nepal, where the first phase of nationwide lockdown was observed from 24 March to 21 July 2020. This sudden halt in human outdoor activities brought positive and negative impacts on forests and wildlife. We undertook a study to learn the impact of the COVID‐19 lockdown on wildlife and forests in the protected areas (PAs) of Nepal. Between July and September 2020, data on illegal activities recorded by the staff of PAs and also those reported by media were collected and analyzed. Key informant interviews (KII) were done with the park officers and security personnel by virtual communication (telephone, messenger app, and video call) to collect detailed information and for corroboration. The collected data were categorized into four groups: (a) wildlife killed, (b) wildlife injured, (c) arrest incidents related to forest crime, and (d) arrest incidents related to wildlife crime. Data from the fiscal year 2019–2020 were analyzed, comparing before lockdown and after. Among 20 PAs investigated during the lockdown, the study found substantial increases in wildlife death in two PAs, Banke National Park, and Bardia National Park. Similarly, Chitwan National Park (CNP) and Shivapuri Nagarjun National Park (SNNP) witnessed a rise in wildlife poaching. CNP and SNNP are located close to densely populated cities and also have human settlements in their peripheries. Wildlife was sighted freely roaming inside PAs during the lockdown, presumably because the absence of visitors and human activities during the lockdown decreased disturbance. Thus, the wildlife was enjoying the freedom of movement on the one hand, and on the other hand was threatened by poachers, many of whom were laid off from other activities and were taking advantage of the lapse in security.     

Multilocus phylogeny and taxonomy of pikas of the subgenus Ochotona (Lagomorpha,Ochotonidae)

A complete set of pika taxa, belonging to the subgenus Ochotona, was studied using craniometric and multilocus genetic analyses. We examined 1,007 skulls, covering the entire distribution range of the subgenus, as well as the mitochondrial COI gene and three nuclear introns in 31 specimens, representing nearly all taxa in question. An additional set of 167 COI gene sequences and 357 cytb gene sequences was analysed to enlarge the geographical extent of genetic data and to compare the results with previous publications. We found that the subgenus consists of eight species. One of them, Ochotona morosa, is elevated to the full species rank for the first time. The name of this species is given preliminarily and should be studied additionally. Several cases of interspecies hybridisation were found, which indicates that mitochondrial DNA cannot be used for species identification in this subgenus. Taxon Ochotona qionglaiensis, which was recently described as a separate species, represents a relic mitochondrial lineage of Ochotona thibetana. Another recently described species, Ochotona yarlungensis, is a Nubra pika with its native mitochondrial DNA, firstly found for this species. Intraspecies variation was analysed for several species for the first time. Thus, new subspecies (Ochotona thibetana fengii ssp. n.) was found within O. thibetana.