RESUMEN
The first measurement of the three-body photodisintegration of longitudinally polarized (3)He with a circularly polarized γ-ray beam was carried out at the High Intensity γ-ray Source facility located at Triangle Universities Nuclear Laboratory. The spin-dependent double-differential cross sections and the contributions from the three-body photodisintegration to the (3)He Gerasimov-Drell-Hearn integrand are presented and compared with state-of-the-art three-body calculations at the incident photon energies of 12.8 and 14.7 MeV. The data reveal the importance of including the Coulomb interaction between protons in three-body calculations.
RESUMEN
The incidence of oral cancer remains high and is associated with many deaths in both Western and Asian countries. Several risk factors for the development of oral cancer are now well known, including smoking, drinking and consumption of smokeless tobacco products. Genetic predisposition to oral cancer has been found in certain cases but its components are not yet entirely clear. In accordance with the multi-step theory of carcinogenesis, the natural history of oral cancer seems to gradually evolve through transitional precursor lesions from normal epithelium to a full-blown metastatic phenotype. A number of genomic lesions accompany this transformation and a wealth of related results has appeared in recent literature and is being summarized here. Furthermore, several key genes have been implicated, especially well-known tumor suppressors like the cyclin-dependent kinase inhibitors, TP53 and RB1 and oncogenes like the cyclin family, EGFR and ras. Viral infections, particularly with oncogenic HPV subtypes and EBV, can have a tumorigenic effect on oral epithelia and their role is discussed, along with potential therapeutic interventions. A brief explanatory theoretical model of oral carcinogenesis is provided and potential avenues for further research are highlighted.
Asunto(s)
Neoplasias de la Boca/genética , Neoplasias de la Boca/fisiopatología , Transformación Celular Neoplásica , Humanos , Modelos Biológicos , Factores de RiesgoRESUMEN
UNLABELLED: In the developed world, intraoral malignancies are more frequent in males than females. Recent observations from Greece suggest that the number of females is increasing. AIM: The present study investigates gender and age statistics among subjects with cancers of the mouth or leukoplakia. METHODS: Five hundred and twelve subjects of Greek origin participated in this analysis. Chi-square and logistic regression statistics were used to compare if there are differences in participants' gender and age, stratified by histological type. RESULTS: Epithelial cancers and leukoplakia exhibited equal distributions among men and women. Men were diagnosed at a much younger age than women. Our data also indicates a progression in the process of epithelial cancer development, as benign leukoplakia was diagnosed 2-4 years earlier than epithelial dysplasia and 8 years earlier than squamous cell carcinoma (SSC). The same age difference was observed in non-Hodgkin's lymphoma, although the male to female ratio was 3:1. In regards to anatomy, 47% of SSC appeared in the tongue. The most prevalent site for the development of non-Hodgkin's lymphoma was the gingival (50%), followed by the palate (40%). CONCLUSION: Although oral cancer occurs earlier in men than women, the risk of females tends to be similar to that of males.
Asunto(s)
Leucoplasia Bucal/epidemiología , Neoplasias de la Boca/epidemiología , Factores de Edad , Carcinoma de Células Escamosas/epidemiología , Carcinoma Verrugoso/epidemiología , Distribución de Chi-Cuadrado , Femenino , Grecia/epidemiología , Humanos , Modelos Logísticos , Linfoma no Hodgkin/epidemiología , Masculino , Persona de Mediana Edad , Factores Sexuales , Factores de TiempoRESUMEN
Early detection and treatment improve the prognosis for oral cancer. Delays from the onset of symptoms to clinical diagnosis are common. Our aim is to identify factors associated with this delay. Between 1995 and 1998, we interviewed 105 consecutive patients with histologically confirmed oral cancer in Greece. If 21 or more days elapsed from the time the patient noticed major symptoms to a definitive diagnosis, we called it a delay (52% of cases). We used logistic and linear regression to estimate odds ratios of delayed diagnosis and to identify correlates of length of delay, respectively. Former smokers had a 4.3 times greater risk of delayed diagnosis compared with current smokers (95% confidence interval: 1.1-17.1). The length of delay was greater among single patients, non-smokers, or those with stage IV tumors. Clinicians should be advised that delay in the diagnosis of oral cancer occurs frequently, even in individuals who do not smoke heavily.
Asunto(s)
Carcinoma de Células Escamosas/diagnóstico , Neoplasias de la Boca/diagnóstico , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Consumo de Bebidas Alcohólicas , Peso Corporal , Carcinoma de Células Escamosas/genética , Estudios de Casos y Controles , Intervalos de Confianza , Empleo , Femenino , Grecia , Humanos , Modelos Lineales , Modelos Logísticos , Masculino , Estado Civil , Persona de Mediana Edad , Neoplasias de la Boca/genética , Estadificación de Neoplasias , Oportunidad Relativa , Salud Bucal , Neoplasias Faríngeas/diagnóstico , Neoplasias Faríngeas/genética , Factores de Riesgo , Factores Sexuales , Fumar , Estadísticas no Paramétricas , Factores de TiempoRESUMEN
Oral and pharyngeal cancer (OC) mortality is very low in Greece, especially among men, compared to other European countries. We conducted a case-control study of OC in Athens, and obtained information on tobacco, alcohol use and other potential risk factors and confounding variables for 110 incident cases and 115 hospital-based controls. We used multivariate logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Tobacco smoking (pack years, P(trend)=0.01) and alcohol use (drinks/week, P(trend)=0.07) were independent risk factors, with a multiplicative effect for combined exposures (OR, 8.3; 95% CI, 2.4-29.1, for >28 alcohol drinks/week and >50 pack years of cigarette smoking). The type of alcoholic beverage also seemed important: drinking ouzo and tsipouro (liquors of high ethanol concentration) was associated with greater increased OC risk than drinking comparable amounts of wine, beer or dark spirits. While alcohol drinking is more common for male cases versus controls, few men reported regularly consuming large quantities of ethanol associated with highest risk of OC in other studies. This may partially explain the low rates of male OC mortality in Greece. Among the 38% of our cases who were women, however, neither smoking nor alcohol drinking frequencies were significantly elevated compared to controls, and so the etiology of OC risk in females requires further investigation.
Asunto(s)
Consumo de Bebidas Alcohólicas/efectos adversos , Neoplasias de la Boca/etiología , Neoplasias Faríngeas/etiología , Fumar/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Bebidas Alcohólicas/efectos adversos , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Distribución por Sexo , Factores SexualesRESUMEN
Studies on the involvement of the human papillomavirus (HPV) in initiation and progression of oral neoplasia have generated conflicting results. The observed discrepancy is attributable mainly to the varying sensitivity of the applied methodologies and to epidemiologic factors of the examined patient groups. To evaluate the role of HPV in oral carcinogenesis, we analyzed 53 potentially neoplastic and neoplastic oral lesions consisting of 29 cases of hyperplasia, 5 cases of dysplasia, and 19 cases of squamous cell carcinomas, as well as 16 oral specimens derived from healthy individuals. A highly sensitive nested polymerase chain reaction (PCR) assay was used, along with type-specific PCR, restriction fragment length polymorphism analysis, dot blotting, and nonisotopic in situ hybridization. Nested PCR revealed the presence of HPV DNA in 48 of the 53 (91%) pathologic samples analyzed, whereas none (0%) of the normal specimens was found to be infected. Positivity for HPV was independent of histology and the smoking habits of the analyzed group of patients. At least one "high risk" type, such as HPV 16, 18, and 33, was detected by type-specific PCR in 47 (98%) infected specimens, whereas only 1 (2%) squamous cell carcinoma was solely infected by a "low risk" type (HPV 6). HPV 16 was the prevailing viral type, being present in 71% of infected cases. Single HPV 16 and HPV 18 infections were confirmed by restriction fragment length polymorphism. HPV 58 was detected by dot blotting in three hyperplastic lesions. HPV positivity and genotyping were further confirmed, and the physical status of this virus was evaluated by nonisotopic in situ hybridization. Diffuse and punctate signals, indicative of the episomal and integrative pattern of HPV infection, were observed for low- and high-risk types, respectively. Our findings are suggestive of an early involvement of high-risk HPV types in oral carcinogenesis.
Asunto(s)
Carcinoma de Células Escamosas/virología , Mucosa Bucal/virología , Neoplasias de la Boca/virología , Papillomaviridae/aislamiento & purificación , Lesiones Precancerosas/virología , Adulto , Anciano , Carcinoma de Células Escamosas/patología , Femenino , Genotipo , Humanos , Hiperplasia/patología , Hiperplasia/virología , Immunoblotting , Hibridación in Situ , Masculino , Persona de Mediana Edad , Mucosa Bucal/patología , Neoplasias de la Boca/patología , Papillomaviridae/genética , Infecciones por Papillomavirus/patología , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Lesiones Precancerosas/patología , Infecciones Tumorales por Virus/patologíaRESUMEN
Geranylgeranyl diphosphate (GGPP) synthase, an enzyme that regulates taxane biosynthesis, was purified to homogeneity from cell cultures of Taxus baccata. The molecular weight of the native protein was estimated to be 76+/-2 kDa, resulting from the association of two apparently identical subunits having a molecular weight of 38 kDa. Farnesyl diphosphate (K(m) 2.46 µM) in combination with isopentenyl diphosphate (K(m) 1.5 µM) was the most effective substrate. Dimethyl allyl diphosphate was a poorer substrate (K(m) 12.7 µM). Mn(2+) ion at 4 mM in combination with Mg(2+) of 2 mM gave the greatest stimulation of activity. The pI of the enzyme was lower than 4 and the pH optimum was between 6.9 and 7.2. The enzyme activity was found in the 20000xg (centrifugal force) pellet and a non-ionic detergent was used for its extraction. The inclusion of detergent was not necessary during subsequent chromatographic steps.
Asunto(s)
Acitretina/administración & dosificación , Carboximetilcelulosa de Sodio/análogos & derivados , Carboximetilcelulosa de Sodio/administración & dosificación , Leucoplasia/tratamiento farmacológico , Neoplasias de la Boca/tratamiento farmacológico , Administración Oral , Administración Tópica , Biopsia con Aguja , Femenino , Humanos , Leucoplasia/patología , Masculino , Mucosa Bucal/efectos de los fármacos , Mucosa Bucal/patología , Neoplasias de la Boca/patología , Pronóstico , Índice de Severidad de la EnfermedadRESUMEN
Angiolymphoid hyperplasia with eosinophilia (ALHE) is a benign uncommon entity whose aetiology and pathogenesis is under debate. Clinically, it is characterised by cutaneous papules or nodules. Cases of this entity reported in the oral mucosa are very rare. We describe such a case, discuss the problems of histological differential diagnosis between ALHE and other diseases of the region and review the literature.
Asunto(s)
Hiperplasia Angiolinfoide con Eosinofilia/diagnóstico , Hemangioendotelioma Epitelioide/diagnóstico , Mucosa Bucal , Adulto , Diagnóstico Diferencial , Femenino , Humanos , InmunohistoquímicaAsunto(s)
Alcaloides/química , Péptidos Cíclicos/química , Alcaloides/biosíntesis , Alcaloides/farmacología , Animales , Antiinfecciosos/farmacología , Antifúngicos/farmacología , Técnicas de Cultivo , Hipnóticos y Sedantes/farmacología , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Fragmentos de Péptidos/química , Péptidos Cíclicos/biosíntesis , Péptidos Cíclicos/farmacología , Plantas Medicinales/metabolismo , EspectrofotometríaRESUMEN
Histoplasmosis as a serious opportunistic infection in association with AIDS has assumed considerable importance. We have gathered 20 case reports from the literature of oral histoplasmosis in HIV-infected patients. In some cases, oral lesions appear to be the primary or only manifestation of disease. We report one such case of oral histoplasmosis in a bisexual man who was seen with ulcerations on the palate and proved to be infected by HIV.
Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico , Histoplasmosis/diagnóstico , Úlceras Bucales/microbiología , Adulto , Bisexualidad , Western Blotting , Ensayo de Inmunoadsorción Enzimática , Infecciones por VIH/diagnóstico , Humanos , Masculino , Hueso Paladar/microbiologíaRESUMEN
Paraneoplastic pemphigus (PNP) is a relatively recently described autoimmune disorder, distinguished from pemphigus vulgaris or foliaceus by specific clinical, histologic and immunologic criteria. In the present review, 18 cases of paraneoplastic pemphigus reported so far are discussed. The polymorphism, extent and persistence of skin and mucosal lesions are discussed while the problems of differential diagnosis and the significance of the associated neoplasms are also stressed. The underlying malignancy in the majority of the cases has been of lymphoid origin and has preceded the clinical presentation of pemphigus. All patients have had oral and cutaneous lesions. In 66.6% of the patients there was a poor response to therapy.
Asunto(s)
Síndromes Paraneoplásicos/patología , Pénfigo/patología , Anciano , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
The aim of this study was to determine the microbial profile of periodontal lesions in HIV seropositive patients and to compare it with rapidly progressing periodontal lesions in systemically healthy patients. The subgingival microflora of 20 CDC II, 20 CDC III, 20 CDC IV/V and 20 systemically healthy patients with rapidly progressing periodontitis was examined. Four sites with greatest probing depth in each patient were selected for microbiological sampling. The samples were cultured aerobically and anaerobically for bacterial isolation using selective and non-selective media. Isolates were characterized to species level by conventional biochemical tests and various identification kits. The microflora of periodontitis lesions within the three stages of the HIV infection was similar to that of progressing periodontitis in systemically healthy adults including Campylobacter rectus, Capnocytophaga spp., Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Selenomonas spp. and Peptostreptococcus micros. However, HIV seropositive periodontitis lesions harboured a range of exogenous pathogens rarely associated with common types of periodontitis including Staphylococcus aureus, Enterobacter cloaca, Pseudomonas aeruginosa, Candida albicans, Enterococcus faecalis, Enterococcus avium, Clostridium difficile, Aspergillus fumigatus, Klebsiella pneumoniae and Mycoplasma incognitum. The lack of immune effector and regulatory cells in HIV infected patients could in fact explain the increase of some opportunistic pathogens and the characteristic and rapidly progressing nature of the periodontal disease in these patients.
Asunto(s)
Alcaloides/química , Péptidos Cíclicos/química , Plantas/química , Alcaloides/biosíntesis , Alcaloides/clasificación , Alcaloides/farmacología , Antiinfecciosos/química , Antiinfecciosos/farmacología , Antifúngicos/química , Antifúngicos/farmacología , Hipnóticos y Sedantes/química , Hipnóticos y Sedantes/farmacología , Espectroscopía de Resonancia Magnética , Conformación Molecular , Estructura Molecular , Péptidos Cíclicos/biosíntesis , Péptidos Cíclicos/farmacologíaRESUMEN
The oral manifestations of infectious diseases is a major topic since the prevalence rate has increased, and usually poses diagnostic and therapeutic dilemmas to the oral clinician. The clinical features of the most common and important oral infectious diseases are discussed.
Asunto(s)
Enfermedades de la Boca/microbiología , Enfermedades de la Boca/virología , Actinomicosis Cervicofacial/patología , Candidiasis Bucal/patología , Gingivitis Ulcerosa Necrotizante/patología , Gonorrea/complicaciones , Infecciones por VIH/complicaciones , Enfermedad de Boca, Mano y Pie/patología , Humanos , Lepra/complicaciones , Lepra/patología , Enfermedades de la Boca/etiología , Enfermedades de la Boca/patología , Micosis/complicaciones , Noma/patología , Infecciones por Papillomavirus/complicaciones , Estomatitis Herpética/patología , Sífilis/complicaciones , Sífilis/patología , Tuberculosis Bucal/patologíaRESUMEN
A case of a 9-year-old boy with AIDS and severe hairy leukoplakia on the tongue is reported. Clinically it appears as a bilateral whitish-grey, nonremovable lesion on the lateral margins of the tongue with characteristic vertical corrugations. The lesion failed to respond to topical and systemic antifungal treatment. In contrast, it completely disappeared after treatment with 600 mg acyclovir per day for 1 month. During the hairy leukoplakia development the CD4-lymphocytes count was 95/microL.
Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/tratamiento farmacológico , Leucoplasia Vellosa/tratamiento farmacológico , Enfermedades de la Lengua/etiología , Aciclovir/uso terapéutico , Niño , Humanos , Leucoplasia Vellosa/etiología , Masculino , Enfermedades de la Lengua/tratamiento farmacológicoRESUMEN
Glycogen storage disease type 1b is a rare metabolic disorder which affects the transport system of glucose-6-phosphatase metabolism. As a result, hepatomegaly, failure to thrive, renal dysfunction and recurrent infections occur in affected patients. In this paper, the oral complications in three children with glycogen storage disease type 1b are discussed. Oral ulcers were a common finding, probably due to severe neutropenia and impaired neutrophil migration which characterises the onset of this rare disorder.