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1.
Although Myanmar exports millions of dollars of rattan cane each year, the last systematic treatment of rattans in this country was done over 100 years ago, and virtually nothing has been written about the collection and trade of this important forest resource. Here we report the results from a study of rattans in the Hukaung Valley Tiger Reserve in northern Myanmar. A total of 15 species of rattan were encountered; seven species are new records for Myanmar and two species are new to science. Inventory transects revealed that the density of commercial rattans in local forests averages 40.5 canes ≽4m long/hectare. Populations of all species appear to be actively regenerating. The current pattern of rattan exploitation, however, is largely uncontrolled and will eventually lead to resource depletion unless some form of management is implemented.  相似文献   
2.

Background

Leptospirosis is an emerging zoonosis that is often under-recognized in children and commonly confused with dengue in tropical settings. An enhanced ability to distinguish leptospirosis from dengue in children would guide clinicians and public health personnel in the appropriate use of limited healthcare resources.

Methodology/Principal Findings

We conducted a prospective, hospital-based, study of children with acute febrile illnesses and dengue in Thailand. Among the children without dengue, we identified those with leptospirosis using anti-leptospira IgM and microscopic agglutination titers in paired acute and convalescent blood samples. We then performed a case-control comparison of symptoms, signs, and clinical laboratory values between children with leptospirosis and dengue.In a semi-rural region of Thailand, leptospirosis accounted for 19% of the non-dengue acute febrile illnesses among children presenting during the rainy season. None of the children with leptospirosis were correctly diagnosed at the time of hospital discharge, and one third (33%) were erroneously diagnosed as dengue or scrub typhus. A predictive model to distinguish pediatric leptospirosis from dengue was generated using three variables: the absolute neutrophil count, plasma albumin, and aspartate aminotransferase levels in the first 72 hours of illness.

Conclusions/Significance

Unrecognized leptospirosis can be a significant cause of “dengue-like” febrile illness in children. Increased awareness of pediatric leptospirosis, and an enhanced ability to discriminate between leptospirosis and dengue early in illness, will help guide the appropriate use of healthcare resources in often resource-limited settings.  相似文献   
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Like many other gobies, male Isaza (Gymnogobius isaza) which are endemic to Lake Biwa, Japan, exclusively care for broods in nests. This goby may have an optimal range of brood size (i.e., an average clutch size of about 2000–3000 eggs) within which they may produce larger numbers of hatching young because much larger broods may be destroyed by fungal infection before hatching. This optimal brood size hypothesis (Takahashi et al. in J Ethol 22:153–159, 2004) predicts that (1) after spawning, both males and females will refuse additional spawning by other gravid females (second females) to keep brood sizes within optimal ranges, (2) larger fish will repel second females more successfully than will smaller fish, and thus, (3) both sexes prefer larger mates. To examine these predictions, we first observed Isaza’s aggressive behaviors in aquaria and investigated whether fish attacked and repelled second females that were introduced after spawning, and, if so, what were the sizes of fish that did so. Large fish, regardless of sex, aggressively prevented second females from entering the nest, but second females larger than the pairs displaced the pair females forcibly and spawned eggs into their clutches. Mate choice experiments showed that males preferred large females. Although females’ choice of large mates was not confirmed, many results may largely coincide with the predictions of the optimal brood size hypothesis. Thus, Isaza males’ choice of large mates will be advantageous for defending against brood parasitism by conspecific females and for achieving optimal clutch size.  相似文献   
6.
Bartonellae were detected in a total of 152 (23.7%) of 642 tissues from 108 (48.4%) of 223 small mammals trapped in several urban areas of Nepal. Based on rpoB and gltA sequence analyses, genotypes belonging to seven known Bartonella species and five genotypes not belonging to previously known species were identified in these animals.  相似文献   
7.

Introduction

The purpose of this study was to evaluate the effects of L-4F, an apolipoprotein A-1 mimetic peptide, alone or with pravastatin, in apoE-/-Fas-/-C57BL/6 mice that spontaneously develop immunoglobulin G (IgG) autoantibodies, glomerulonephritis, osteopenia, and atherosclerotic lesions on a normal chow diet.

Methods

Female mice, starting at eight to nine weeks of age, were treated for 27 weeks with 1) pravastatin, 2) L-4F, 3) L-4F plus pravastatin, or 4) vehicle control, followed by disease phenotype assessment.

Results

In preliminary studies, dysfunctional, proinflammatory high-density lipoproteins (piHDL) were decreased six hours after a single L-4F, but not scrambled L-4F, injection in eight- to nine-week old mice. After 35 weeks, L-4F-treated mice, in the absence/presence of pravastatin, had significantly smaller lymph nodes and glomerular tufts (PL, LP < 0.05), lower serum levels of IgG antibodies to double stranded DNA (dsDNA) (PL < 0.05) and oxidized phospholipids (oxPLs) (PL, LP < 0.005), and elevated total and vertebral bone mineral density (PL, LP < 0.01) compared to vehicle controls. Although all treatment groups presented larger aortic root lesions compared to vehicle controls, enlarged atheromas in combination treatment mice had significantly less infiltrated CD68+ macrophages (PLP < 0.01), significantly increased mean α-actin stained area (PLP < 0.05), and significantly lower levels of circulating markers for atherosclerosis progression, CCL19 (PL, LP < 0.0005) and VCAM-1 (PL < 0.0002).

Conclusions

L-4F treatment, alone or with pravastatin, significantly reduced IgG anti-dsDNA and IgG anti-oxPLs, proteinuria, glomerulonephritis, and osteopenia in a murine lupus model of accelerated atherosclerosis. Despite enlarged aortic lesions, increased smooth muscle content, decreased macrophage infiltration, and decreased pro-atherogenic chemokines in L-4F plus pravastatin treated mice suggest protective mechanisms not only on lupus-like disease, but also on potential plaque remodeling in a murine model of systemic lupus erythematosus (SLE) and accelerated atherosclerosis.  相似文献   
8.
A new cardenolide, 17β-H-periplogenin-3-O-β-d-digitoxoside (1), and a new pregnane glycoside, Δ5-pregnene-3β,16α-diol-d-O-[2,4-O-diacetyl-β-digitalopyranosyl-(1 → 4)-β-d-cymaropyranoside]-16-O-[β-d-glucopyranoside] (2) were isolated from the roots of Streptocaulon tomentosum (Asclepiadaceae) together with a series of known compounds. Their chemotaxonomic significance for the separation of S. tomentosum from Streptocaulon juventas is discussed, suggesting a rather clear distinction of these species.  相似文献   
9.
Internal ribosomal entry sites (IRESs) are structured cis‐acting RNAs that drive an alternative, cap‐independent translation initiation pathway. They are used by many viruses to hijack the translational machinery of the host cell. IRESs facilitate translation initiation by recruiting and actively manipulating the eukaryotic ribosome using only a subset of canonical initiation factor and IRES transacting factors. Here we present cryo‐EM reconstructions of the ribosome 80S‐ and 40S‐bound Hepatitis C Virus (HCV) IRES. The presence of four subpopulations for the 80S•HCV IRES complex reveals dynamic conformational modes of the complex. At a global resolution of 3.9 Å for the most stable complex, a derived atomic model reveals a complex fold of the IRES RNA and molecular details of its interaction with the ribosome. The comparison of obtained structures explains how a modular architecture facilitates mRNA loading and tRNA binding to the P‐site. This information provides the structural foundation for understanding the mechanism of HCV IRES RNA‐driven translation initiation.  相似文献   
10.
Three novel meroterpenoids, insuetolides A-C (1-3) and four drimane sesquiterpenes, the new (E)-6-(4'-hydroxy-2'-butenoyl)-strobilactone A (4) and the known 2α, 9α, 11-trihydroxy-6-oxodrim-7-ene (5), strobilactone A (6) and (E,E)-6-(6',7'-dihydroxy-2',4'-octadienoyl)-strobilactone A (7), were isolated from the EtOAc extract of the culture medium of the marine-derived fungus Aspergillus insuetus (OY-207), which was isolated from the Mediterranean sponge Psammocinia sp. The structures of the compounds were determined by spectroscopic methods. Insuetolides A-C reveal a new carbon skeleton derived from the cyclization of farnesyl and 3, 5-dimethylorsellinic acid. Compounds 1, 6, and 7 exhibited anti-fungal activity towards Neurospora crassa with MIC values of 140, 242, and 162 μM, respectively; and compounds 3, 4, and 7 exhibited mild cytotoxicity towards MOLT-4 human leukemia cells.  相似文献   
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