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1.
Zootaxa ; 4683(2): zootaxa.4683.2.1, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31715924

RESUMO

For the goatfish genus Upeneus Cuvier 1829 (Mullidae), a new taxonomic species group called the "margarethae group" is established which can be distinguished from the six species of the most similar "tragula group" by a combination of the following characteristics: absence of dark pigmentation in the area of the first dorsal-fin tip, 21-25 total gill rakers and 28-30 lateral-line scales. Initially, three recently-described species have been included in the margarethae group: Upeneus margarethae Uiblein Heemstra, 2010, known from the Indian Ocean including the Red Sea and from the Arafura Sea (W Pacific), U. mouthami Randall Kulbicki, 2006, from New Caledonia and Vanuatu (W Pacific), and U. randalli Uiblein Heemstra, 2011, from the Arabian/Persian Gulf and the inner Gulf of Oman (NW Indian Ocean). The present taxonomic review of the margarethae group analyses a large data set of 41 morphometric, 10 meristic and many colour characters obtained from 279 preserved goatfish specimens and 166 fresh-colour photos (plus a fresh-colour drawing). For the nominal species of the group, U. margarethae, a redescription of the colour patterns is provided and new records for Myanmar, Andaman Sea (NE Indian Ocean) and the Gulf of Carpentaria, N Australia (W Pacific), are reported. Three new species are described: U. caudofasciatus n. sp. from the area of the Great Barrier Reef to Torres Strait off NE Australia (Coral Sea, W Pacific), U. gubal n. sp. from the S Gulf of Suez (Northern Red Sea), and U. heterospinus n. sp. from S Indonesia to Singapore, the Gulf of Thailand, Vietnam, Philippines, China, Taiwan and Japan (W Pacific). A comprehensive alpha-taxonomic approach is adopted, considering population differences as well as intraspecific size-related variation in morphology and colour patterns by splitting the data set into two size classes, adults (≥ 65 mm SL) and smaller subadults. Inter- and intraspecific comparisons include statistical analyses for species and population with sufficiently large samples sizes (n ≥ 20). Colour-pattern characterization and analysis are based on photos of recently collected and deceased fish (partly associated with voucher specimens), photos obtained from active or resting fishes in situ or in a tank, and inspection of pigmentation patterns retained in preserved specimens. Species differences are elaborated under consideration of distribution patterns and the characteristics found in the closest-most population of widely distributed species such as U. margarethae, resulting in clear and consistent distinction among the six species in single or in a combination of several characteristics. Comparisons among size classes revealed species-specific patterns in morphometric, meristic and colour changes with increasing size. One species, U. heterospinus n. sp., has seven or eight spines in the dorsal fin which occur in balanced ratio across populations. This is a unique characteristic for Upeneus species which usually have either seven or eight dorsal-fin spines, respectively. The best distinction of Upeneus heterospinus n. sp. from all other congeners is reached by combined examination of dorsal-fin spines with several other characters such as barbel colour, presence of a mid-lateral body stripe, pigmentation patterns (partly retained also in preserved fish), gill-raker and pectoral-fin ray numbers, and body-shape variables. The high degree of overall morphological differentation among the three most common species U. caudofasciatus n. sp., U. heterospinus n. sp. and U. margarethae, as revealed by the statistical comparisons, strongly contrasts with a still signficant, but much lower degree of differentiation among populations. The diagnostic characteristics of the margarethae group are updated and the importance to use the results of this taxonomic review in ongoing fisheries-related and ecological research is emphasized. Requirements for future taxonomic research featuring the stunning diversity of the goatfish genus Upeneus are also discussed.


Assuntos
Perciformes , Distribuição Animal , Animais , Austrália , Cor , Indonésia , Oceano Pacífico
2.
Zootaxa ; 4344(3): 541-559, 2017 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-29245624

RESUMO

For Jansen's goatfish, Parupeneus jansenii (Mullidae), taxonomic knowledge has been rather poor and occurrence information restricted to a few localities only, with verified records from northern Sulawesi and Sunda Street (Indonesia), and Luzon (Philippines). This species is here included in the so-called "heptacanthus" group together with the Indo-Pacific cinnabar goatfish, P. heptacanthus, and five Indian Ocean congenerics, based on an evenly, symmetrically rounded posterior maxilla margin and similarities in meristic characters and preserved colour. In total 29 P. jansenii and 53 P. heptacanthus consisting of types, recently collected material from south-central Vietnam, southern Indonesia, and NE Australia, and geographically related reference material were studied along with single types of the other five heptacanthus-group species and P. angulatus, a morphologically similar Western Indian Ocean species. In total 62 quantitative meristic and morphometric characters including standard length (SL) were analysed after splitting the data into two size classes (small-sized fish, < 110 mm SL, vs. large-sized fish  > 110 mm SL) to account for size-related differences due to allometry. Diagnoses for P. jansenii and P. heptacanthus and a redescription for P. jansenii were prepared. Fresh-fish colour descriptions for both large- and small-sized voucher specimens of P. jansenii are provided and the effects of freshness status on colour patterns is documented. New records for P. jansenii for Vietnam, southern Indonesia and NE Australia (= first verified record for Australia) are reported and depth information (24-100 m depth range) is given for the first time. P. jansenii differs from the co-occurring P. heptacanthus - independently of size - in shallower body and caudal peduncle, smaller maximum head depth, shorter barbels, caudal and pelvic fins, shallower first dorsal fin, shallower first ray of second dorsal fin, and lack of small dark red or reddish-brown spot on or just below the eighth lateral-line scale. The populations of P. jansenii from Vietnam and Australia differ from each other in a single character, the height of the eighth dorsal-fin ray, but both overlap with the intermediate population from Indonesia. This comprehensive alpha-taxonomic approach provides a useful tool for uncovering the diversity of Parupeneus goatfishes.


Assuntos
Peixes , Distribuição Animal , Animais , Austrália , Oceano Índico , Indonésia , Oceano Pacífico , Filipinas , Vietnã
3.
ACS Appl Mater Interfaces ; 8(23): 14824-35, 2016 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-27203860

RESUMO

The use of MgO nanoparticles in polyethylene for cable insulation has attracted considerable interest, although in humid media the surface regions of the nanoparticles undergo a conversion to a hydroxide phase. A facile method to obtain MgO nanoparticles with a large surface area and remarkable inertness to humidity is presented. The method involves (a) low temperature (400 °C) thermal decomposition of Mg(OH)2, (b) a silicone oxide coating to conceal the nanoparticles and prevent interparticle sintering upon exposure to high temperatures, and (c) heat treatment at 1000 °C. The formation of the hydroxide phase on these silicone oxide-coated MgO nanoparticles after extended exposure to humid air was assessed by thermogravimetry, infrared spectroscopy, and X-ray diffraction. The nanoparticles showed essentially no sign of any hydroxide phase compared to particles prepared by the conventional single-step thermal decomposition of Mg(OH)2. The moisture-resistant MgO nanoparticles showed improved dispersion and interfacial adhesion in the LDPE matrix with smaller nanosized particle clusters compared with conventionally prepared MgO. The addition of 1 wt % moisture-resistant MgO nanoparticles was sufficient to decrease the conductivity of polyethylene 30 times. The reduction in conductivity is discussed in terms of defect concentration on the surface of the moisture-resistant MgO nanoparticles at the polymer/nanoparticle interface.

4.
PLoS One ; 9(1): e87272, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24489886

RESUMO

Illicit trade carries the potential to magnify existing tobacco-related health care costs through increased availability of untaxed and inexpensive cigarettes. What is known with respect to the magnitude of illicit trade for Vietnam is produced primarily by the industry, and methodologies are typically opaque. Independent assessment of the illicit cigarette trade in Vietnam is vital to tobacco control policy. This paper measures the magnitude of illicit cigarette trade for Vietnam between 1998 and 2010 using two methods, discrepancies between legitimate domestic cigarette sales and domestic tobacco consumption estimated from surveys, and trade discrepancies as recorded by Vietnam and trade partners. The results indicate that Vietnam likely experienced net smuggling in during the period studied. With the inclusion of adjustments for survey respondent under-reporting, inward illicit trade likely occurred in three of the four years for which surveys were available. Discrepancies in trade records indicate that the value of smuggled cigarettes into Vietnam ranges from $100 million to $300 million between 2000 and 2010 and that these cigarettes primarily originate in Singapore, Hong Kong, Macao, Malaysia, and Australia. Notable differences in trends over time exist between the two methods, but by comparison, the industry estimates consistently place the magnitude of illicit trade at the upper bounds of what this study shows. The unavailability of annual, survey-based estimates of consumption may obscure the true, annual trend over time. Second, as surveys changed over time, estimates relying on them may be inconsistent with one another. Finally, these two methods measure different components of illicit trade, specifically consumption of illicit cigarettes regardless of origin and smuggling of cigarettes into a particular market. However, absent a gold standard, comparisons of different approaches to illicit trade measurement serve efforts to refine and improve measurement approaches and estimates.


Assuntos
Comércio/economia , Crime/estatística & dados numéricos , Impostos , Produtos do Tabaco/economia , Crime/economia , Pesquisa Empírica , Humanos , Fumar/epidemiologia , Indústria do Tabaco/economia , Vietnã
5.
Bioorg Med Chem Lett ; 20(9): 2991-3, 2010 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-20359890

RESUMO

In order to define the structural requirements of phenylthiourea (PTU), a series of thiourea and thiosemicarbazone analogs were prepared and evaluated as inhibitors of melanogenesis in melanoma B16 cells. The most potent analog was 2-(4-tert-butylbenzylidene)hydrazinecarbothioamide (1u) with an IC(50) value of 2.7 microM in inhibition of melanogenesis. The structure for potent inhibitory activity of these derivatives are required with the direct connection of pi-planar structure to thiourea without steric hinderance in PTU derivatives and the hydrophobic substituent at para position in case of semicarbazones.


Assuntos
Benzaldeídos/química , Melanoma Experimental/tratamento farmacológico , Peptídeos/química , Feniltioureia/química , Tiossemicarbazonas/química , Animais , Camundongos , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Peptídeos/síntese química , Peptídeos/uso terapêutico , Feniltioureia/síntese química , Feniltioureia/uso terapêutico , Relação Estrutura-Atividade , Tiossemicarbazonas/síntese química , Tiossemicarbazonas/uso terapêutico
6.
Eur J Med Chem ; 45(6): 2531-6, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20226573

RESUMO

A novel series of chromone analogs were synthesized and evaluated for their inhibitory activity against interleukin-5. Among them compounds 5-Cyclohexylmethoxy-3-(4-hydroxybenzyl)-4H-chromen-4-one (6a, 98% inhibition at 30 microM, IC50<3.0 microM) and 5-Cyclohyxylmethoxy-3-(hydroxymethyl)-4H-chromen-4-one (8a, 84% inhibition at 30 microM, IC50=7.6 microM) showed most potent activity. The structural requirement of chromone analogs possessing the inhibitory activity against IL-5 could be summarized as: (i) importance of hydrophobic group such as cyclohexylmethoxy at 5th position of ring A, (ii) requirement of ring B with small size of hydrogen bonding group with electron donating property such as phenolic hydroxyl group at 4th position and (iii) planarity of the chromen-4-one ring.


Assuntos
Cromonas/síntese química , Cromonas/farmacologia , Interleucina-5/antagonistas & inibidores , Linhagem Celular , Cromonas/química , Cromonas/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Concentração Inibidora 50 , Permeabilidade , Relação Estrutura-Atividade
7.
Arch Pharm Res ; 29(9): 721-7, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17024843

RESUMO

To continue exploration of structure activity relationship of novel 1-(indoline-5-sulfonyl)-4-phenylimidazolidinones (1) reported as anticancer agent with broad spectrum, three 1-(arylsulfonyl)-4-vinylimidazolidinones (2) were synthesized from methyl serinate (3) in 8 steps. Reaction of intermediate 2-phenoxycarbonylaminobut-3-enyl p-toluenesulfonate (10) with arylsulfonamide in the presence of potassium carbonate produced corresponding 2 and N-(4-vinyloxazolidin-2-yl)arylsulfonamide 11 in approximately equal ratio. This reaction is believed to undergo through urea intermediate 16 as shown in scheme 3. 1-Arylsufonyl-4-vinylimidazolidinones 2 show much reduced activity against human colon carcinoma (Colo205), human chronic myelogenous leukemia (K562), and human ovarian adenocarcinoma (SK-OV-3) and compatible activity against human lung carcinoma (A549) compared to 1. Therefore phenyl at 4-position should be the optimum planar motif for the activity of 1.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Hidantoínas/síntese química , Hidantoínas/farmacologia , Compostos de Vinila/síntese química , Compostos de Vinila/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Espectrofotometria Ultravioleta , Relação Estrutura-Atividade , Sais de Tetrazólio , Tiazóis
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