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1.
J Helminthol ; 97: e89, 2023 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-38032079

RESUMEN

The application of integrative taxonomic approaches is useful to species delineation based on a combination of distinct types of characters, here morphological features and ribosomal DNA sequences. In this study, we surveyed ectoparasitic nematodes of the subfamily Merliniinae in cultivated and natural environments in Iran. Results of morphological and morphometrical studies, light and scanning electron microscopic observations, and molecular analyses allowed us the identification of fourteen known and one unknown species including representatives of the genera Amplimerlinius (five species), Geocenamus (one species), Merlinius (three species), Nagelus (two species), Paramerlinius (one species), Scutylenchus (two species), and Telomerlinius (one species). The unknown species, Scutylenchus sp., characterized by having 35-50 incisures at mid-body; lateral field with 6 longitudinal incisures; lip region slightly offset by a constriction, flattened at front end; bearing 5-7 annuli; cephalic framework not refractive; stylet robust, 18.3-27 µm long; post anal intestinal sac absent; tail elongate conical, dorsally convex, with 24 (19-28) annuli in ventral side, ending to a smooth terminus and males common; spicules 24.5-31 µm long. The phylogenetic analyses were carried out using molecular data from nuclear ribosomal DNA (rDNA) genes viz. D2-D3 expansion segments of the large ribosomal subunit (28S rRNA), partial small ribosomal subunit (18S rRNA), and internal transcribed spacer (ITS). The molecular variability of D2-D3 expansion segments of the 28S rRNA and partial 18S rRNA was low in this family in comparison to the ITS region, which could be a more helpful molecular marker in species and genus identification.


Asunto(s)
Nematodos , Tylenchoidea , Masculino , Animales , Filogenia , ARN Ribosómico 28S/genética , ARN Ribosómico 18S/genética , Tylenchoidea/genética , ADN Ribosómico/genética
2.
Parasite Epidemiol Control ; 18: e00252, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35573893

RESUMEN

Background: Human head louse, Pediculus humanus capitis De Geer, 1767 (Anoplura: Pediculidae), is one of the most frequent ectoparasites infesting Homo sapiens worldwide. Reduced sensitivity to treatment due to genetic mutations, in particular knockdown resistance (kdr) (or target site insensitivity) allele, has led to this infestation prevalence. Molecular characterization of this resistance has a crucial impact on selecting appropriate treatment protocol. The aim of this study was to investigate kdr gene mutations on voltage-sensitive sodium channel (VSSC) among wild head lice samples from Fars province, southern Iran. Methods: Head lice were collected using plastic detection combs on girls enrolled in public schools from 10 counties in Fars province. The specimens were screened in 10 pools (each pool per county containing 35 specimens), with three pools (30%) being positive. Following species identification with valid entomological keys, 350 (68%) out of 514 randomly collected adult head lice were analyzed after their somatic genomic DNA extraction using Sinaclon kit. Samples were investigated by polymerase chain reactions (PCR), and the amplicon was subsequently sequenced. Results: Sequence analysis showed that the sodium channel genes in the pooled ectoparasites had two intron and three exon regions. Single (L840F), double (I836L, E837K), and triple novel point mutations (V875L, Q876P, S879V); the last involving two concomitant allelic substitutions; were discovered in the second and third exon regions of head louse DNA on chromosome II from three (30%) counties. Other exon or intron regions remained non-mutated from the remaining seven counties. Conclusions: The detection of six amino acid substitutions from 30% of examined head lice among infested schoolgirls reveal that mutants are minutely developing. These findings provide further incentive to recapitulate the legitimacy of current control measures and resolve dynamics of resistance in human head louse populations.

3.
Eur J Prosthodont Restor Dent ; 30(1): 36-48, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-33934579

RESUMEN

Color assessment remains a challenging aspect of esthetic dentistry. This study aimed to evaluate inter-operator agreement and accuracy in assessing shade parameters and to investigate the effect of different clinical backgrounds of the operators under different lighting conditions. Three veneers with a single shade (VITA VM7, shade 2M2: VITA Zahnfabrik, Bad Säckingen) and different shade characteristics (lustre, translucency and opacity) were assessed by 24 operators with different backgrounds using natural and color-corrected light (Trueshade, Interempresas Media, S.L.U. - Grupo Nova Àgora, Spain). Shade assessment accuracy was only 5.5% using natural light and 9.7% using Trueshade. The majority of operators identified value and hue correctly, although chroma was mostly identified incorrectly. The most accurate assessments were recorded by technicians, and translucency was the characteristic to be least accurately recorded. Inter-operator agreement of shade was better with Trueshade compared without Trueshade, although group agreements of shade characteristics were higher without Trueshade for lustre and opacity, but not for translucency. Operators showed limited agreement and poor accuracy in assessing shade and shade characteristics and the clinical background had an effect on shade selection. Technicians were more reliable in shade assessment. Trueshade could be a promising tool to improve shade assessment outcomes.


Asunto(s)
Diseño de Prótesis Dental , Coloración de Prótesis , Color , Percepción de Color
4.
Phys Chem Chem Phys ; 19(29): 19094-19102, 2017 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-28702606

RESUMEN

The density functional formalism has been used to investigate the stability and the properties of small palladium clusters supported on graphdiyne layers. The large triangular holes existing on the graphdiyne structure provide efficient sites to hold the clusters at small distances from the plane of the graphdiyne layer. The cluster adsorption energies, between 3 and 4 eV, are large enough to maintain the clusters tightly bound to the triangular holes. The competition between dispersion of Pd atoms on graphdiyne and growth of Pd clusters in the triangular holes of the layer is also discussed. In addition, the triangular holes can be simultaneously decorated with clusters on both sides. This indicates that palladium clusters could be used to build nanostructures formed by stacked graphdiyne layers with tailored interlayer distances controlled by the size of the clusters. The size of the clusters also controls the electronic HOMO-LUMO gap of the material.

5.
Nucl Phys A ; 960: 147-164, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28413255

RESUMEN

The in-medium sum rules are employed to calculate the shifts in the mass and residue as well as the scalar and vector self-energies of the heavy [Formula: see text] and [Formula: see text] baryons, with Q being b or c quark. The maximum shift in mass due to nuclear matter belongs to the [Formula: see text] baryon and it is found to be [Formula: see text]. In the case of residue, it is obtained that the residue of [Formula: see text] baryon is maximally affected by the nuclear medium with the shift [Formula: see text]. The scalar and vector self-energies are found to be [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text].

6.
Trop Biomed ; 29(1): 1-8, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22543597

RESUMEN

Human cutaneous leishmaniasis (CL) is a major notifiable public health problem in many parts of Iran. It is often caused by the zooflagellate parasite Leishmania major which is mainly transmitted by the bites of female phlebotomine sandflies belonging to the genus Phlebotomus (Diptera: Psychodidae). The annual incidence of CL in Fars province, southern Iran, was about 108-144 in 2007. The leishmanial infections of wild sandflies that may act as vectors were thus investigated at an endemic focus in this province. In all 330 female Phlebotomus sandflies were screened for the detection of Leishmania-specific kinetoplast DNA (kDNA) by polymerase chain reaction (PCR) methods. A two stage nested PCR protocol was used to establish the identity of Leishmania major species in naturally infected sandflies. The L. major kDNA was detected in 18 (5.5%) individual sandflies which belonged to four different Phlebotomus species (Phlebotomus papatasi, Phlebotomus salehi, Phlebotomus sergenti and P. major group). For the first time, one naturally infected P. salehi specimen contained the kDNA of the protozoan parasite, L. major, with a main band of 560 base pairs identified using the nested PCR method. It seems most likely therefore that P. salehi is potentially a rare sylvatic vector of L. major parasites in parts of this province. This is the first combined morphological and molecular studies of P. salehi in Iran.


Asunto(s)
ADN de Cinetoplasto/aislamiento & purificación , Vectores de Enfermedades , Leishmania major/genética , Leishmania major/aislamiento & purificación , Parasitología/métodos , Phlebotomus/parasitología , Reacción en Cadena de la Polimerasa/métodos , Animales , Enfermedades Endémicas , Femenino , Humanos , Irán/epidemiología , Leishmaniasis Cutánea/epidemiología , Leishmaniasis Cutánea/parasitología , Zoonosis/epidemiología , Zoonosis/parasitología
7.
Trop Biomed ; 28(2): 418-24, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22041764

RESUMEN

Linear dermatitis (or dermatitis linearis, DL) is a skin blistering inflammatory lesion caused by exposure to the pederin toxin from rove beetles. Although it is prevalent in many countries of the Middle East region, this is not a notifiable disease. In recent years, a number of clinical symptoms outbreaks of DL has been reported from a few neighboring countries of Iran, but no report of experimental treatment among small laboratory rodents is known. This is a prerequisite to ascertain the nature of the best treatment strategy in cases of infestation with these beetles, as it occurs among local settlers during hot seasons in certain parts of the southern Iranian province of Fars. Live Paederus beetles were collected, identified to species level, sexed apart and partly processed to obtain their hemolymph toxin pederin in ethanol for dermal application on guinea pigs. Two Paederus species were found. Paederus ilsae (Bernhauer) (Coleoptera: Staphylinidae) was more abundant than P. iliensis (Coiffait). Recovery from DL due to live P. ilsae beetles was quicker and less complex than that of pederin in ethanol on guinea pigs. The application of potassium permanganate with calamine to heal DL was also more effective than fluocinolone treatment. This topical corticosteroid is thus considered less able to avert the cytotoxic action of pederin on the skin of guinea pigs than the antipruritic and cleansing agents. It seems likely that fluocinolone has certain effects which delays the recovery period for the treated skin.


Asunto(s)
Escarabajos/patogenicidad , Dermatitis por Contacto/tratamiento farmacológico , Piranos/toxicidad , Animales , Antiinflamatorios/administración & dosificación , Escarabajos/clasificación , Modelos Animales de Enfermedad , Combinación de Medicamentos , Femenino , Compuestos Férricos/administración & dosificación , Fluocinolona Acetonida/administración & dosificación , Fluocinolona Acetonida/análogos & derivados , Cobayas , Mordeduras y Picaduras de Insectos/complicaciones , Irán , Masculino , Permanganato de Potasio/administración & dosificación , Piranos/aislamiento & purificación , Resultado del Tratamiento , Óxido de Zinc/administración & dosificación
8.
Ann Trop Med Parasitol ; 105(6): 431-7, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22117852

RESUMEN

Gerbillus nanus Blanford, 1875 known as Baluchistan gerbil, is a granivorous solitary naked-footed species. No evidence of its natural infection with the protozoan parasite, Leishmania, has so far been provided. Cutaneous leishmaniasis (CL) is a major public health problem in many parts of the world, including Iran. The annual nationwide incidence of human CL due to Leishmania major (CLM) in endemic rural areas was above 18,000 cases in 2008. The detection of L. major in rodents is of fundamental importance for incriminating them as potential reservoirs of CLM infection. Between April 2007 and April 2008, following detection of 245 clinical cases in Jask region of south-east Iran, wild rodents were captured and checked by the microscopic slide smears for leishmanial infections. Overall, 106 gerbilline rodents were captured from which 17 were identified as Gerbillus nanus. Females of Meriones hurrianae, Tatera indica and G. nanus were found to be naturally infected with L. MAJOR. The presence of these parasites in G. nanus has never been reported before. All the amastigote-infected rodents came from the eastern plain of this region, except one T. indica from the western plain which was found to be smear-positive or kinetoplast DNA-positive by PCR. The highest (11·8%) prevalence of infection among rodents confirmed by PCR to be infected with L. major was attributed to Baluchistan gerbil, G. nanus, which is thus incriminated as a potential reservoir host of L. major in Iran.


Asunto(s)
Reservorios de Enfermedades/parasitología , Gerbillinae/parasitología , Leishmania major/aislamiento & purificación , Leishmaniasis Cutánea/veterinaria , Enfermedades de los Roedores/parasitología , Animales , Electroforesis en Gel de Agar/métodos , Femenino , Humanos , Irán/epidemiología , Leishmaniasis Cutánea/epidemiología , Leishmaniasis Cutánea/transmisión , Masculino , Reacción en Cadena de la Polimerasa/métodos , Enfermedades de los Roedores/epidemiología , Enfermedades de los Roedores/transmisión
9.
Ann Trop Med Parasitol ; 105(3): 217-24, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21801500

RESUMEN

Human cutaneous leishmaniasis (CL) is of increasing public-health importance in Iran. On 10 July 2003, two mild earthquakes struck the rural town of Zarindasht in the southern Iranian province of Fars. The results of passive detection of CL cases in this town (in which patients with any skin lesions were evaluated) from April 2002 to April 2004 indicated that the earthquakes may have led to an outbreak of the disease; annual incidence increased from 58·6 detected cases/100,000 in the 12 months before the earthquakes to (an outbreak peak of) 864 detected cases/100,000 in the following 12 months. In addition, the incidence of detected CL in the town that was struck by the earthquakes in 2003 was significantly higher in the 12 months after the earthquakes than that recorded, over the same 12 months, for Fars province as a whole (P<0·05). Most (70%) of the cases detected in the town were aged ≤10 years, about half (50·4%) of the detected skin lesions were on the face, and most (89·7%) of the skin lesions were caused by Leishmania major. Incidence over the study period showed marked seasonality, with most (79·5%) of the detected cases occurring between November and February. In areas where the disease is endemic, CL may need to be considered among the health threats posed by natural disasters such as earthquakes, and increased surveillance for CL after future earthquakes may be justified.


Asunto(s)
Desastres , Terremotos , Leishmaniasis Cutánea/epidemiología , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Brotes de Enfermedades , Femenino , Humanos , Incidencia , Lactante , Irán/epidemiología , Leishmaniasis Cutánea/diagnóstico , Leishmaniasis Cutánea/patología , Masculino , Persona de Mediana Edad , Salud Rural/estadística & datos numéricos , Estaciones del Año , Adulto Joven
10.
J Med Entomol ; 46(5): 1094-8, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19769040

RESUMEN

Visceral leishmaniasis is caused by Leishmania infantum, which is transmitted to humans by bites of phlebotomine sand flies and is one of the most important public health problems in Iran. To identify the vector(s), an investigation was carried out in Germi district, an important focus of the disease in Ardebil province in northwestern Iran, during July-September 2004 and 2005. Using sticky papers, CDC light traps and aspirators, 3,560 sand flies were collected and identified to species. Host bloodmeal preference and Leishmania infections in female specimens were evaluated using enzyme-linked immunosorbent assay (ELISA) for the former and microscopic examination followed by polymerase chain reaction (PCR) assay using species-specific kinetoplast minicircle primers for the latter. Nine sand fly species are present in the district, including Phlebotomus kandelakii Shchurenkova, Phlebotomus perfiliewi transcaucasicus Perfil'ev, Phlebotomus major Annandale, Phlebotomus balcanicus Theodor, Phlebotomus halepensis Theodor, Phlebotomus brevis Theodor & Meshghali, Phlebotomus papatasi Scopoli, Sergentomyia dentata Sinton, and Sergentomyia sintoni Pringle, with P. p. transcaucasicus being the most prevalent representative of the genus Phlebotomus at 45%. The anthropophilic index for P. p. transcaucasicus was 36.3%, indicating a strong preference for humans. Of 905 female P. p. transcuacasicus dissected, 10 (1.1%) were found naturally infected with promastigotes. Species-specific amplification of promastigotes eluted from Giemsa-stained slides revealed specific PCR products of L. infantum DNA. Based on its high anthropophily and natural infections with L. infantum, and the fact that it was the only species found infected with L. infantum, we conclude that P. p. transcaucasicus is the principal vector of L. infantum in northwestern Iran.


Asunto(s)
Insectos Vectores/parasitología , Leishmania infantum/aislamiento & purificación , Leishmaniasis Visceral/transmisión , Phlebotomus/parasitología , Animales , Femenino , Irán
11.
J Med Entomol ; 45(4): 726-31, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18714874

RESUMEN

Ghir-Karzin district is one of the most important endemic foci of visceral leishmaniaisis (VL) in Fars province of southern Iran. To identify the vector(s) of Leishmania in this focus, a total of 2,539 sand flies were collected during June to September 2005. Eleven species (six Phlebotomus and five Sergentomyia) were identified, of which Phlebotomus papatasi Scopoli and Phlebotomus major Annandale were the first (37.4%) and third (11.2%) most common species, respectively. Natural leptomonad infections were observed in two P. papatasi (4.25%) and three P. major (6.65%) specimens on dissection and microscopic examination. Using a Leishmania genus-specific standard polymerase chain reaction (PCR; primers RV1-RV2) and a species-specific nested-PCR (primers LINR4, LIN17, and LIN 19), Leishmania infantum and Leishmania major kinetoplast minicircle DNA was detected in 6 of 72 P. major (8.3%) and 4 of 65 P. papatasi (6.1%), respectively. This is the first detection of L. infantum in P. major, implicating this sand fly as a probable vector of VL in Iran.


Asunto(s)
Leishmania infantum/aislamiento & purificación , Phlebotomus/parasitología , Animales , ADN/genética , ADN/aislamiento & purificación , ADN Protozoario/genética , ADN Protozoario/aislamiento & purificación , Irán , Leishmania infantum/genética , Phlebotomus/clasificación , Reacción en Cadena de la Polimerasa , Especificidad de la Especie
12.
Pak J Biol Sci ; 10(12): 2061-5, 2007 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-19093447

RESUMEN

A study was made in rural region of Shahrood city, Semnan province in the central of Iran during 2005 to investigate of vectors of zoonotic cutaneous leishmaniasis. Sticky traps and an aspirator were used for collecting of sandflies. Three species of Phlebotomus papatasi, P. caucasicus and Sergentomyia sintoni were collected and identified and the first species was dominant (53%). Nested PCR method were employed for identifying of isolated parasites of dissected female of sandflies. Among the dissected sand flies 3 out of 24 (12.5%) Phlebotomus papatasi and 2 out of 48 (4.2%) Phlebotomus caucasicus were found naturally infected with promastigotes. Species-specific amplification ofGiemsa staind promastigote slides revealed specific PCR production of Leishmania major DNA in the infected P. papatasi and P. caucasicus sand flies. Having high prevalence and infection rate provide enough evidence to incriminate of P. papatasi as the main and proven vector of cutaneous leishmaniasis to human in the region and the species of P. caucasicus play the second role for maintenance of disease between rodents.


Asunto(s)
Insectos Vectores/parasitología , Leishmaniasis Cutánea/transmisión , Zoonosis/transmisión , Animales , Secuencia de Bases , Cartilla de ADN/genética , ADN Protozoario/genética , ADN Protozoario/aislamiento & purificación , Humanos , Irán , Leishmania major/genética , Leishmania major/aislamiento & purificación , Leishmaniasis Cutánea/parasitología , Phlebotomus/parasitología , Reacción en Cadena de la Polimerasa , Psychodidae/parasitología , Especificidad de la Especie , Zoonosis/parasitología
13.
Ann Trop Med Parasitol ; 100(1): 63-8, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16417715

RESUMEN

The incidence of human visceral leishmaniasis (VL) caused by Leishmania infantum, which is endemic in several parts of Iran, has recently increased in the Nourabad-Mamassani district of Fars province, in the south of the country. Between 2003 and 2005, 12,688 sandflies were caught in this focus, using CDC miniature light traps, sticky traps and aspirators, in an attempt to identify the main vector of L. infantum. When 120 of the parous, female Phlebotomus (Paraphlebotomus) alexandri caught were individually checked for Leishmania infection, in an assay based on PCR and kinetoplast minicircle primers (LINR4 and LIN17), five (4.2%) of the flies were found to be infected with L. infantum. Thirty-nine (32.5%) of the 120 blood-fed Ph. alexandri checked in an ELISA were found positive for human blood. Since Ph. alexandri was the third-most common species caught (representing over 17% of the total catch), was clearly anthropophilic, and was not infrequently infected with L. infantum, it is probably an important vector in the Nourabad-Mamassani focus. Although other sandfly species have been found naturally infected with promastigotes in Iran, Ph. alexandri is the first that has been proven to harbour L. infantum in the country.


Asunto(s)
Insectos Vectores/parasitología , Leishmania infantum , Leishmaniasis Visceral/transmisión , Phlebotomus/parasitología , Animales , ADN de Cinetoplasto/análisis , Enfermedades Endémicas , Femenino , Humanos , Irán/epidemiología , Leishmaniasis Visceral/epidemiología , Masculino , Reacción en Cadena de la Polimerasa/métodos
14.
Am J Orthod Dentofacial Orthop ; 104(3): 240-50, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8362785

RESUMEN

This study attempted to discover what black Americans find attractive about their profile. Fifteen black patients (eight males, seven females) were selected at random and used as models. Lateral photographs were taken on each patient, and a computer was used to alter the profiles to depict different levels of bimaxillary protrusion. Each patient was manipulated into four different profile types according to specific numerical guidelines. A vertical reference line from soft tissue glabella, perpendicular to Frankfort horizontal, was used to measure the lip position. In each profile type only the horizontal lip position was altered. The four profile types were classified as S (straight) BM1, (bimax one), BM2 (bimax two) and BM3 (bimax three). The S profile was considered a straight or white facial profile, and the BM3 was an extreme example of bimaxillary protrusion. The photographs were surveyed among black and white laypersons, general dentists, and orthodontists. The results found the BM1 profile to be the most attractive. This was consistent with all groups surveyed. The BM1 profile would be considered a slightly convex profile and is more protrusive than white orthodontic norms. In this study comparisons of this profile to other standards are made and treatment considerations for black patients are discussed.


Asunto(s)
Belleza , Población Negra , Negro o Afroamericano/psicología , Estética Dental , Cara/anatomía & histología , Maxilar/anatomía & histología , Adulto , Cefalometría , Distribución de Chi-Cuadrado , Comparación Transcultural , Femenino , Humanos , Masculino , Fotograbar , Valores de Referencia , Factores Sexuales , Estados Unidos
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