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1.
J Fish Biol ; 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38480996

RESUMEN

Members of the genus Cyprinion (Cypriniformes: Cyprinidae) are found in the Indus River basin west to the Arabian Peninsula and the Tigris-Euphrates River drainages (Persian Gulf basin). The taxonomic status of Cyprinion including Cyprinion muscatense is poorly understood when compared to other cyprinid genera. C. muscatense has been considered as a member of the Cyprinion watsoni-microphthalmum group and a valid species endemic to the Arabian Peninsula. Here, we redescribe C. muscatense based on an integrative morphological and molecular approach and freshly sampled material from several localities in the Oman Mountains ecoregion. The results showed that C. muscatense is distinguished from the other Cyprinion species in the Arabian Peninsula by having a short, thin, and slightly serrated last unbranched dorsal fin ray; the lower number of circumpeduncular scales; lateral line scales; and also scales between the lateral line and the dorsal-fin origin. Subterminal mouth, presence of one pair of small barbels at the mouth corner, 3-4 unbranched and 9½-10½ dorsal-fin branched rays, 12-14 pectoral-fin rays, 7-8 pelvic-fin rays, 2-3 unbranched and 6½-7½ branched anal-fin rays, and 37-40 lateral line scales are other morphological characteristics of C. muscatense. C. muscatense is also well distinguished by molecular characters among its congeners. The first molecular phylogenetic analysis of the genus, covering all currently recognized Cyprinion species except for C. watsoni, is also presented. C. muscatense is resolved as the sister species to another endemic fish of the Arabian Peninsula Cyprinion mhalense, with a Kimura-2-Parameter model distance of 5.3%.

2.
Zootaxa ; 5134(4): 451-503, 2022 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-36101053

RESUMEN

Oman, a country in Southwest Asia, situated on the southeastern quarter of the Arabian Peninsula presents a high level of biological diversity especially marine elements. Although arid habitats cover most parts of Oman (82%), the region has several freshwater systems that are vital for the survival of people as well as for different groups of animals and plants. Research works on Oman biodiversity including terrestrial and marine, have been steadily increasing over the last few decades, but freshwater ecosystems have not been well investigated. Oman comprises parts of three freshwater ecoregions including the Oman Mountains, Southwestern Arabian Coast, and Arabian Interior having xeric freshwaters and endorheic (closed) basins which support a variety of inland fishes. The current checklist provides for each species of inland waters of Oman all recognized and named taxa, documenting recent changes and controversies in nomenclature, its records, taxonomic status, synonyms, etymology, common English name, short description, range expansion, and detailed distribution map based on several field surveys throughout the country. We also provide native, endemic, and introduced species. The diversity of inland fishes of Oman included in this annotated checklist consists of 23 recognized species in 15 genera, 10 families, seven orders, and a class. Also, for the first time, we report and confirm the presence of four species in the inland waters of Oman. The most diverse order is Cypriniformes (nine species, 39.13%), followed by Gobiiformes (six species, 26.09%), Cyprinodontiformes (three species, 13.04%), Cichliformes (two species, 8.69%), and Centrarchiformes, Gonorynchiformes and Mugiliformes (one species, 4.35% each). 21 native species (91.3%) in nine families and two exotic species (8.7%) in two families are listed here. Out of 21 native species, eight species (16.8%) in two families are endemic elements that are restricted to the Oman territory only. Identification of all recognized species was confirmed by DNA barcoding (mitochondrial COI). Oman Mountains Ecoregion (OME), Southwestern Arabian Coast Ecoregion (SACE), and Arabian Interior Ecoregion (AIE) harbor 15, 12, and one species, respectively. The provided data will be necessary for increasing the fish knowledge, the development of competent and pragmatic management plans and effective conservation policies.


Asunto(s)
Ciprinodontiformes , Ecosistema , Animales , Arabia , Biodiversidad , Humanos , Omán
3.
Zootaxa ; 5133(4): 543-554, 2022 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-36101084

RESUMEN

Glossogobius giuris was originally described as Gobius giuris from the Ganges River, India. However, based on the uncertainty of its type locality and its apparent widespread distribution, a comprehensive study is being carried out to define the correct taxonomic status of this taxon. The South African population of the Glossogobius from St. Lucia Lake, KwaZulu-Natal was described as Glossogobius tenuiformis by Fowler in 1934. It has usually been considered as Glossogobius giuris but Hoese and Hammer indicated that it was a distinct species (2021: 83). Here, based on morphological characters and a molecular data set, we redescribe Glossogobius tenuiformis and assign the Oman populations of Glossogobius to this species. Glossogobius tenuiformis is distinguished from G. giuris by the absence or very short (and often only a few papillae long) sensory papilla line 6; presence of single rows of the sensory papillae in each cheek line, 1216 pre-dorsal scale counts, and 1+1+911, usually 1+1+10, gill rakers on outer face of first arch. Glossogobius tenuiformis is also distinguished by molecular characters. Glossogobius tenuiformis shows 16% genetic distance with other members of this species complex, that includes G. laticeps from Vietnam, Bangladesh and China, G. giuris from South Africa and India and giuris C from India, Myanmar, Nepal, Bangladesh and Vietnam, and the highest genetic distance (24%) with G. circumspectus.


Asunto(s)
Perciformes , Animales , Peces/anatomía & histología , Branquias , Omán , Sudáfrica
4.
Microsc Res Tech ; 84(12): 3128-3149, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34292653

RESUMEN

The scale morphology of a native goby, Awaous jayakari (Gobiidae) was studied using scanning electron microscopy and light microscopy. The morphological descriptions were based on the scale's type, shape, and features of the anterior, posterior, and lateral fields. Further characteristics of the focus, circuli, radii, lepidonts, and cteni, were investigated. Morphometric indices were calculated for some scales. Shape variability of scales was high in different regions. However, the majority of scales displayed a polygonal shape (hexagonal and pentagonal). Both ctenoid and cycloid scales were observed in the studied fishes. The ctenoid scale of A. jayakari was peripheral and characterized by the presence of one row of marginally located spines in two completed and uncompleted subtypes. The focus was positioned posteriorly or postero-centrally. The microscopic examinations revealed the presence of lepidonts of different sizes being very tiny, small, or prominent performing flat, blunt, pointed, short, or truncated shapes. The rostral margin of the scales was convex to moderately flattened and represented striate, scalloped, or waved types. Lateral fields were often flattened in all regions, while convex in the lateral fields of the scales of some individuals. The posterior field showed variations in different regions, for example, tapered and flattened ends. The anterior-posterior axis presented a laterally expanded or an elongated extension. The considerable morphological variation in the scales of various body regions makes it difficult to nominate a typical scale to be used in taxonomic studies. However, the key scales can be used for the comparison of different Awaous species.


Asunto(s)
Perciformes , Animales , Peces , Humanos , Microscopía Electrónica de Rastreo
5.
Vasc Med ; 26(4): 426-433, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33818200

RESUMEN

Coronavirus disease 2019 (COVID-19) may predispose patients to venous thromboembolism (VTE). Limited data are available on the utilization of the Pulmonary Embolism Response Team (PERT) in the setting of the COVID-19 global pandemic. We performed a single-center study to evaluate treatment, mortality, and bleeding outcomes in patients who received PERT consultations in March and April 2020, compared to historical controls from the same period in 2019. Clinical data were abstracted from the electronic medical record. The primary study endpoints were inpatient mortality and GUSTO moderate-to-severe bleeding. The frequency of PERT utilization was nearly threefold higher during March and April 2020 (n = 74) compared to the same period in 2019 (n = 26). During the COVID-19 pandemic, there was significantly less PERT-guided invasive treatment (5.5% vs 23.1%, p = 0.02) with a numerical but not statistically significant trend toward an increase in the use of systemic fibrinolytic therapy (13.5% vs 3.9%, p = 0.3). There were nonsignificant trends toward higher in-hospital mortality or moderate-to-severe bleeding in patients receiving PERT consultations during the COVID-19 period compared to historical controls (mortality 14.9% vs 3.9%, p = 0.18 and moderate-to-severe bleeding 35.1% vs 19.2%, p = 0.13). In conclusion, PERT utilization was nearly threefold higher during the COVID-19 pandemic than during the historical control period. Among patients evaluated by PERT, in-hospital mortality or moderate-to-severe bleeding were not significantly different, despite being numerically higher, while invasive therapy was utilized less frequently during the COVID-19 pandemic.


Asunto(s)
COVID-19/terapia , Recursos en Salud/tendencias , Necesidades y Demandas de Servicios de Salud/tendencias , Grupo de Atención al Paciente/tendencias , Pautas de la Práctica en Medicina/tendencias , Embolia Pulmonar/terapia , Terapia Trombolítica/tendencias , Tromboembolia Venosa/terapia , Adulto , Anciano , Anciano de 80 o más Años , COVID-19/complicaciones , COVID-19/diagnóstico , COVID-19/mortalidad , Femenino , Hemorragia/etiología , Hemorragia/mortalidad , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/etiología , Embolia Pulmonar/mortalidad , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/etiología , Tromboembolia Venosa/mortalidad
6.
Appl Opt ; 57(11): 2881-2889, 2018 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-29714289

RESUMEN

Discrimination of aerosol types is very important, because different aerosols are created from diverse sources having different chemical, physical, and optical properties. In the present study, we have analyzed the seasonal classification of aerosol types by multiple clustering techniques, using AERosol Robotic NETwork (AERONET) data during 2010-2013 over Zanjan, Iran. We found that aerosol optical depth (AOD) showed pronounced seasonal variations of a summer high and winter low. Conversely, the values of the Angstrom exponent (AE) in winter and fall were higher than in spring and summer, which confirmed the presence of fine particles, while the low value of AE in the summer and spring represented the existence of coarse particles. Single Scattering Albedo (SSA) variations revealed the presence of scattering aerosols like dust in spring, summer, and fall while the dominance of absorbing-type aerosols in winter were also observed. The influence of local anthropogenic activities has caused a higher concentration of fine aerosols, and a higher fine mode fraction (FMF) of AOD in winter was recorded. Classification of aerosol types was carried out by analyzing different aerosol properties such as AOD versus AE, extinction Angstrom exponent (EAE) versus SSA, EAE versus absorption Angstrom exponent (AAE), FMF AOD versus EAE, and SSA versus FMF AOD. The analysis revealed the presence of dust and polluted dust in spring, summer, and fall in the atmosphere of Zanjan. Urban/industrial aerosols were available in all seasons, especially in fall and winter. The mixed aerosols existed in all seasons over the study location; however, no biomass burning aerosols were found. The Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) aerosol subtype profiles showed the dominance of dust and polluted dust in spring and summer. However, the presence of polluted dust and industrial smoke during fall and winter were also noted over the study site.

7.
J Coll Physicians Surg Pak ; 18(8): 502-5, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18798588

RESUMEN

OBJECTIVE: To determine the clinical course of Buerger's disease as observed in two vascular surgery centers located in the capital of Iran. STUDY DESIGN: Case series. PLACE AND DURATION OF STUDY: Sina and Imam Hospitals, Tehran, Iran, during the years 1997 to 2002. METHODOLOGY: The records of all the patients admitted with Buerger's disease diagnosed on the basis of Shionoya's clinical criteria were studied. Their clinical characteristics, treatment offered and short-term follow-up results are described as frequencies and percentages. RESULTS: A total of 116 patients, aged 41.1+/-11.3 years, were enrolled. All patients were males; 99% of them were smokers with an average of 22.9 pack-years of tobacco use. Lower-extremity was affected in 102 (87.9%) patients, upper-extremity in 3 (2.6%) patients and both in 11 (9.5%). The most frequent reasons for being referred to hospital were ischemic ulcers (90.5%), claudication (87.9%), paresthesia (75.9%), rest pain (66.4%), gangrene (60.3%), Raynaud's phenomenon (23.3%) and thrombophlebitis (9.5%). Diagnostic arteriography, vascular bypass surgery and sympathectomy were performed in 60%, 24% and 83% of the patients, respectively. Sixty-eight patients (58.6%) had one of the following amputations: toe 36 (52.9%), transmetatarsal 3 (4.4%), below knee 25 (36.8%), finger 3 (4.4%) and above knee one (1.5%) patient. CONCLUSION: Since the studied hospitals are the referral centers for vascular surgery in Iran admitting patients with severe symptoms; therefore, a higher number of complications and amputations was found in the present study. Upper extremity involvement as well as the occurrence of thrombophlebitis and Raynaud's phenomenon was rather infrequent among the studied cases.


Asunto(s)
Tromboangitis Obliterante/diagnóstico , Adolescente , Adulto , Anciano , Femenino , Humanos , Irán/epidemiología , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Tromboangitis Obliterante/epidemiología , Tromboangitis Obliterante/fisiopatología , Tromboangitis Obliterante/cirugía , Enfermedades Vasculares
8.
Pharmacogenet Genomics ; 15(7): 493-501, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15970797

RESUMEN

There are two functional Omega class glutathione transferase (GST) genes in humans. GSTO1 is polymorphic with several coding region alleles, including an A140D substitution, a potential deletion of E155 and an E208K substitution. GSTO2 is also polymorphic with an N142D substitution in the coding region. We investigated the effect of these variations on the enzyme's thioltransferase, dehydroascorbate reductase, monomethylarsonate reductase and dimethylarsonate reductase activities. Variant proteins were expressed in Escherichia coli and purified by Ni-agarose affinity chromatography. GSTO2-2 was insoluble and had to be dissolved and refolded from 8 M urea. The A140D and E208K substitutions in GSTO1-1 did not alter specific activity. The deletion of E155 caused a two- to three-fold increase in the specific activity with each substrate. This deletion also caused a significant decrease in the enzyme's heat stability. The E155 deletion has been linked to abnormal arsenic excretion patterns; however, the available data do not clearly identify the cause of this abnormality. We found that GSTO2-2 has activity with the same substrates as GSTO1-1, and the dehydroascorbate reductase activity of GSTO2-2 is approximately 70-100-fold higher than that of GSTO1-1. The polymorphic N142D substitution had no effect on the specific activity of the enzyme with any substrate. The most notable feature of GSTO2-2 was its very high dehydroascorbate reductase activity, which suggests that GSTO2-2 may significantly protect against oxidative stress by recycling ascorbate. A defect in ascorbate metabolism may provide a common mechanism by which the Omega class GSTs influence the age-at-onset of Alzheimer's and Parkinson's diseases.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Arsenicales/metabolismo , Glutatión Transferasa/metabolismo , Oxidorreductasas/metabolismo , Enfermedad de Parkinson/metabolismo , Edad de Inicio , Sustitución de Aminoácidos , Ácido Deshidroascórbico/metabolismo , Genotipo , Glutarredoxinas , Glutatión Transferasa/química , Calor , Humanos , Polimorfismo Genético , Proteína Disulfuro Reductasa (Glutatión)/metabolismo , Pliegue de Proteína , Eliminación de Secuencia , Especificidad por Sustrato
9.
Methods Enzymol ; 401: 78-99, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16399380

RESUMEN

The Omega class of cytosolic glutathione transferases was initially recognized by bioinformatic analysis of human sequence databases, and orthologous sequences were subsequently discovered in mouse, rat, pig, Caenorhabditis elegans, Schistosoma mansoni, and Drosophila melanogaster. In humans and mice, two GSTO genes have been recognized and their genetic structures and expression patterns identified. In both species, GSTO1 mRNA is expressed in liver and heart as well as a range of other tissues. GSTO2 is expressed predominantly in the testis, although moderate levels of expression are seen in other tissues. Extensive immunohistochemistry of rat and human tissue sections has demonstrated cellular and subcellular specificity in the expression of GSTO1-1. The crystal structure of recombinant human GSTO1-1 has been determined, and it adopts the canonical GST fold. A cysteine residue in place of the catalytic tyrosine or serine residues found in other GSTs was shown to form a mixed disulfide with glutathione. Omega class GSTs have dehydroascorbate reductase and thioltransferase activities and also catalyze the reduction of monomethylarsonate, an intermediate in the pathway of arsenic biotransformation. Other diverse actions of human GSTO1-1 include modulation of ryanodine receptors and interaction with cytokine release inhibitory drugs. In addition, GSTO1 has been linked to the age at onset of both Alzheimer's and Parkinson's diseases. Several polymorphisms have been identified in the coding regions of the human GSTO1 and GSTO2 genes. Our laboratory has expressed recombinant human GSTO1-1 and GSTO2-2 proteins, as well as a number of polymorphic variants. The expression and purification of these proteins and determination of their enzymatic activity is described.


Asunto(s)
Glutatión Transferasa , Isoenzimas , Secuencia de Aminoácidos , Animales , Glutarredoxinas , Glutatión Transferasa/química , Glutatión Transferasa/clasificación , Glutatión Transferasa/genética , Glutatión Transferasa/metabolismo , Humanos , Isoenzimas/química , Isoenzimas/clasificación , Isoenzimas/genética , Isoenzimas/metabolismo , Modelos Moleculares , Datos de Secuencia Molecular , Familia de Multigenes , Polimorfismo Genético , Conformación Proteica , Proteína Disulfuro Reductasa (Glutatión)/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Distribución Tisular
10.
Virus Res ; 94(2): 113-20, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12902040

RESUMEN

Cricket paralysis virus (Dicistroviridae: Cripavirus) (CrPV) naturally has a wide range of insect hosts which is reflected in its ability to infect several cultured insect cell lines. The expression of viral gene products is controlled by two kinds of internal ribosome entry site (IRES) elements, 5' and intergenic (IG). Using seven cultured cell lines we tested the functionality of both IRES elements by transfection with bi-cistronic RNA constructs. In six of the seven cell lines, expression initiated from both IRES's was significantly higher than that from a control construct and in five of these six lines the expression from the 5'-IRES was higher than that from the IG-IRES. Permissiveness of each of the cell lines for replication of CrPV was tested by infection with purified virions and transfection with viral RNA. Only three of the cell lines were fully permissive for CrPV replication and no correlation between permissiveness and IRES activity was apparent. These results suggest that while IRES function is required for permissiveness, additional cellular and/or viral factors, involved in processing of viral products, packaging of viral particles and interacting with the cap-dependent translation machinery of host cells, are necessary for CrPV to be able to replicate in any given cell.


Asunto(s)
Regiones no Traducidas 5' , ADN Intergénico , Virus de Insectos/fisiología , Biosíntesis de Proteínas , Virus ARN/fisiología , Secuencias Reguladoras de Ácido Ribonucleico , Animales , Línea Celular , Genes Reporteros , Virus de Insectos/genética , Luciferasas/metabolismo , Virus ARN/genética , Virus ARN/crecimiento & desarrollo , Proteínas Recombinantes/metabolismo , Transfección , Replicación Viral
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