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1.
Commun Agric Appl Biol Sci ; 78(2): 199-207, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-25145241

RESUMEN

Field studies were conducted under irrigation system at Burg El-Arab area (50 K.m. west of Alexandria city) to study some ecological aspects of Parlatoria oleae (Colvee) and its parasitoid, Aphytis maculicornis (Masi) that infested olive and plum trees during the two successive years of 2010 and 2011. Field observations revealed that the most of the inspected individuals occurred mainly on the branches of plum trees as compared with those found on leaves, but on olive the insect occurred on all the plant parts including fruits. On plum trees, the obtained data showed that the population of P. oleae reached the maximum during April, November and January in the first year, but in the second one it had four peaks of high population levels during March, August, November and January. The maximal percent as adult females was observed during March, September and January, whereas the adult males appeared only during October and November. The parasitized individuals by A. maculicornis represented higher rate of parasitization from March to August in the first year that extended to September in the second year. On olive trees under irrigation the population of Parlatoria scale and its parasitoid was relatively low. It had three high peaks, during March, December and February in the first year, while in the second one the population reached the maximum during March, December and February. The parasitoid Aphytis maculicormis appeared in March and April marking high percentage levels in the first year, noticeably it was nearly parasitized the scale insect all the year round.


Asunto(s)
Hemípteros/fisiología , Olea/parasitología , Enfermedades de las Plantas/parasitología , Prunus/parasitología , Riego Agrícola , Animales , Árabes , Egipto , Femenino , Frutas/parasitología , Hemípteros/crecimiento & desarrollo , Masculino , Dinámica Poblacional , Estaciones del Año
2.
J Pathol ; 209(1): 15-24, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16463268

RESUMEN

HOX genes are a large family of regulatory genes implicated in the control of developmental processes. HOX genes are involved in malignant transformation and progression of different types of tumour. Despite intensive efforts to delineate the expression profiles of HOX genes in other cell types, nothing is known regarding the global expression profile of these genes in normal human astrocytes and astrocytomas. The present study has analysed the expression profile of the 39 class I HOX genes in normal human astrocytes (NHA and E6/E7), two well-established glioblastoma cell lines (U-87 MG and U-1242-MG), as well as neoplastic (WHO grades II/III and IV) and non-neoplastic temporal lobe specimens with hippocampal sclerosis and medically intractable epilepsy. RT-PCR, quantitative real-time PCR, immunocytochemistry, and western blot analyses revealed differential expression of nine HOX genes (A6, A7, A9, A13, B13, D4, D9, D10, and D13) in normal human astrocytic cell lines and non-neoplastic temporal lobe specimens. The data show that HOX genes are differentially expressed in neoplastic and non-neoplastic astrocytes and that multiple HOX genes are overexpressed in glioblastoma cell lines, astrocytomas (II/III), and glioblastoma multiforme. The differential expression of HOX genes in normal and neoplastic astrocytes suggests a role for these genes in brain tumourigenesis.


Asunto(s)
Astrocitos/metabolismo , Genes Homeobox , Glioblastoma/genética , Astrocitoma/genética , Astrocitoma/metabolismo , Western Blotting , Línea Celular , ADN Complementario/genética , ADN de Neoplasias/genética , Expresión Génica , Perfilación de la Expresión Génica/métodos , Glioblastoma/metabolismo , Proteínas de Homeodominio/metabolismo , Humanos , Proteínas de Neoplasias/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Lóbulo Temporal/metabolismo , Células Tumorales Cultivadas
4.
Mol Carcinog ; 27(4): 298-307, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10747294

RESUMEN

The skin tumor initiators N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and 7,12-dimethylbenz[a]anthracene (DMBA) differ in effectiveness when tumor formation is promoted by 12-O-tetradecanoylphorbol-13-acetate (TPA). Even at high doses, MNNG is less effective, producing fewer benign and malignant tumors with a longer latent period. In DMBA-initiated skin, 10 wk of TPA promotion produced a maximal tumor response. With MNNG, 20 wk of TPA promotion was required, producing nearly four times as many papillomas as 10 wk of promotion. Promotion of MNNG-initiated skin with mezerein induced the appearance of very rapidly-growing papillomas within 5 wk, 3 wk earlier than the first TPA-promoted papillomas. Thus, MNNG may induce a novel mutation resulting in a population of initiated cells that respond especially well to mezerein. Since ras mutations are common in experimental tumors in many tissues, we determined the frequency of activating mutations in the Ha-ras, Ki-ras, and N-ras oncogenes. Activating Ha-ras mutations were present in essentially all DMBA-initiated tumors and about 70% of MNNG-initiated tumors. No N-ras mutations were found in tumors lacking other ras mutations. Surprisingly, 41% of the papillomas arising in the first 11 wk in MNNG-initiated, mezerein-promoted mice bore mutations in codon 12 of the Ki-ras oncogene. Activating Ki-ras mutations were also found in more than 60% of squamous cell carcinomas and 40% of keratoacanthomas. Although mutations in Ha-ras are frequently detected in mouse skin tumors, mutations in Ki-ras are rare. This is the first report of mutated Ki-ras in skin tumors from mice initiated by MNNG.


Asunto(s)
Codón , Diterpenos , Genes ras , Metilnitronitrosoguanidina/toxicidad , Mutación , Neoplasias Cutáneas/genética , Terpenos/toxicidad , Animales , Secuencia de Bases , Carcinógenos/toxicidad , Cartilla de ADN , Femenino , Ratones , Mutágenos/toxicidad , Papiloma/inducido químicamente , Papiloma/genética , Neoplasias Cutáneas/inducido químicamente
6.
Br J Cancer ; 77(12): 2230-8, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9649138

RESUMEN

We have used microdissection of paraffin-embedded histological sections and polymerase chain reaction (PCR)-based direct DNA sequencing for 54 transitional cell carcinoma (TCC) of the bladder, to examine critically the association between TP53 nuclear accumulation determined by immunohistochemistry and the presence of TP53 mutations, and to examine their relationship to tumour stage and grade, as well as patient survival. There was a significant association between the presence of TP53-positive nuclei (> 10%) and a higher histological stage and grade (P = 0.0115, P = 0.0151 respectively; Fisher's exact). A significant association between TP53 gene mutations and TP53 nuclear reactivity in more than 10% of tumour cell nuclei was also observed (P = 0.0003; Fisher's exact). Mutations were detected in 18/54 (33%) cases together with the wild-type sequence when analysed from bulk frozen samples, with significant clustering of mutations in exons 7 and 8. The microdissection method distinguished more clearly between heterozygous and/or homozygous alterations of the TP53 tumour-suppressor gene, and clearly showed frequent accumulation of TP53 in the absence of mutations. When microdissecting immunonegative regions from the same paraffin sections, three out of ten samples showed the identical mutations detected in the immunopositive regions. There was a significant association between TP53 immunoreactivity in more than 50% of tumour cell nuclei and decreased survival among all patients (P = 0.0325; log-rank test). The patients with TP53 mutations showed a trend for a shorter survival period; however, the association was not statistically significant at the 95% confidence level (P = 0.132; log-rank test). In conclusion, our observations show that accumulation of TP53 occurs frequently in the absence of mutations, and that such accumulation is nevertheless associated with poor survival when it occurs in a high proportion (> 50%) of tumour cell nuclei.


Asunto(s)
Carcinoma de Células Transicionales/genética , Carcinoma de Células Transicionales/metabolismo , Genes p53 , Mutación , Proteína p53 Supresora de Tumor/biosíntesis , Proteína p53 Supresora de Tumor/genética , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/metabolismo , ADN de Neoplasias/genética , Disección , Exones , Humanos , Inmunohistoquímica , Adhesión en Parafina , Reacción en Cadena de la Polimerasa , Pronóstico , Proteína p53 Supresora de Tumor/metabolismo
8.
Cranio ; 15(1): 94-5, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9586494

RESUMEN

In summary, reviewing the patients history, re-examining the patient, re-evaluating the imaging findings, evaluating prior treatment, incorporating additional treatment, exploring other possible contributing factors, and screening the patient's level of cooperation can lead to discovery of additional issues which may, when properly handled, result in successful nonsurgical treatment and avoid unnecessary surgeries.


Asunto(s)
Trastornos de la Articulación Temporomandibular/cirugía , Toma de Decisiones , Humanos , Anamnesis , Trastornos de la Articulación Temporomandibular/terapia , Insuficiencia del Tratamiento
12.
Cranio ; 14(1): 55-62, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9086877

RESUMEN

In the literatures, the relationship between missing teeth or malocclusion and the symptoms of temporomandibular joint disorder such as frequent headaches, earaches, sinus pain, and jaw pain, has been documented. However, there were no specific details as to which teeth were missing to cause these symptoms. In this project the relationship between missing first molars in adult female subjects to the previously mentioned symptoms was studied using one group of 65 subjects with missing one, two, three, or four first molars and a control group of 67 subjects with no missing first molars. The study revealed a significant relationship of missing first molar(s) and the occurrence of headaches, earaches, sinus pain, and jaw pain.


Asunto(s)
Oclusión Dental Traumática/complicaciones , Arcada Parcialmente Edéntula/complicaciones , Diente Molar , Síndrome de la Disfunción de Articulación Temporomandibular/etiología , Adulto , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Dolor de Oído/etiología , Dolor Facial/etiología , Femenino , Cefalea/etiología , Humanos , Persona de Mediana Edad , Encuestas y Cuestionarios
14.
Cranio ; 13(2): 121-7, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8697498

RESUMEN

This article presents a simple systematic methodology in interpretation of parasagittal and coronal tomography views of the temporomandibular joint (TMJ). A step-by-step approach for screening the condyle, articulating eminence and fossa, and the joint as a whole is discussed.


Asunto(s)
Cóndilo Mandibular/diagnóstico por imagen , Trastornos de la Articulación Temporomandibular/diagnóstico por imagen , Articulación Temporomandibular/diagnóstico por imagen , Tomografía por Rayos X/métodos , Humanos
15.
Cranio ; 12(2): 120-4, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8055586

RESUMEN

Dentists of different specialties have been called upon for their expert testimony in dental or related injury cases. These injuries can be due to an auto accident, a fall, professional negligence or injury by an animal. The practitioner is asked to evaluate the injury, write a report and perhaps testify in a deposition or a court of law for a professional opinion. This article is to discuss the role of the dental practitioner in litigation. The dentist-witness' responsibilities, legal protections, the necessary tools to give an opinion, the characteristics of a good expert witness, the demeanor in a deposition and court appearance are discussed.


Asunto(s)
Odontólogos , Testimonio de Experto , Humanos , Rol
17.
J Gen Orthod ; 2(2): 15-8, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1801940

RESUMEN

Malpractice lawsuits due to temporomandibular joint (TMJ) and odontostomatognathic (OSG) injuries following dental therapy are increasing. Therefore, dentists and their staff must know how to screen patients to determine pre-existing conditions. Anatomical and physiological considerations are presented. Three major steps such as taking a good history, examining the patient carefully, and establishing adequate records are discussed in detail.


Asunto(s)
Gestión de Riesgos , Trastornos de la Articulación Temporomandibular/diagnóstico , Registros Odontológicos , Humanos , Anamnesis , Ortodoncia Correctiva/efectos adversos , Articulación Temporomandibular/lesiones
18.
Todays FDA ; 2(4): 1C, 6C-8C, 1990 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2206683

RESUMEN

Malpractice lawsuit cases due to temporomandibular joint/soft tissue injuries following dental therapy are increasing. Therefore, dentists and their staffs must know how to recognize, document and avoid any possible aggravation or precipitation of TMJ disorder. TMJ anatomy, biomechanics and mechanisms of TMJ injuries are presented. Etiological factors such as psychological factors, parafunctional activities, malocclusion, trauma, iatrogenic causes, systemic conditions, developmental disorders, neoplastic growth or medications are discussed. Preventive measures addressed include: history-taking, patient examination, complete records, the assessment of the patient's general condition, documentation of pre-existing findings, informing and educating the patient, performing only the necessary procedures, modifying appointments, selecting less traumatic dental techniques, avoiding sudden occlusal alterations and preparedness to handle unwanted complications.


Asunto(s)
Trastornos de la Articulación Temporomandibular/diagnóstico , Articulación Temporomandibular/lesiones , Medicina Defensiva , Atención Odontológica/efectos adversos , Humanos , Trastornos de la Articulación Temporomandibular/prevención & control
19.
Todays FDA ; 1(3): 1C-3C, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2700660

RESUMEN

Controversy exists over the value of the TMJ condylar position in the fossa. Many clinicians associate the concentric position to the normal individuals and the retruded position to the dysfunctional condition. It is also recommended that therapeutically, the condyle should be placed on the posterior slope of the articulating eminence. Different groups of investigators claim that the condylar position, centric, retruded or protruded has little or no value and is not correlated with dysfunctional situations. This controversy is attributed to the inconsistency of research methodology. Using a large number of subjects, defining age and sex, careful selection of subject, using tomographic analysis with similar section locations and excluding individuals with disturbed occlusal condition are recommended for a research of this type. The conclusion is that the condylar position is an end product of many dynamic changes such as growth and remodeling, functional matrix activities, occlusal alteration, functional adaptation and individual variation. It is suggested that diagnosis and treatment of TMJ disorders should not be based solely on the radiographic position of the condyle. Consideration of general body conditions is an essential part of total patient management. TM joint condylar position has been explained as the position of the mandibular condyles in the glenoid fossa when teeth are in maximum intercuspation. Clinicians have based their diagnosis and treatment of temporomandibular joint disorder on this position. The optimal condylar position has been a controversial matter in dentistry for many years. The purpose of this paper is to review the literature pertaining to condylar position and to discuss its significance in clinical practice.


Asunto(s)
Cóndilo Mandibular/anatomía & histología , Articulación Temporomandibular/anatomía & histología , Humanos
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