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2.
Osteoporos Int ; 28(8): 2465-2473, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28451732

RESUMEN

Root amputation, extraction of a single tooth, bone loss or severe tooth mobility, and an unclosed wound were significantly associated with increased risk of developing medication-related osteonecrosis of the jaw (MRONJ). We recommend a minimally traumatic extraction technique, removal of any bone edges, and mucosal wound closure as standard procedures in patients receiving bisphosphonates. INTRODUCTION: Osteonecrosis of the jaws can occur following tooth extraction in patients receiving bisphosphonate drugs. Various strategies for minimizing the risk of MRONJ have been advanced, but no studies have comprehensively analyzed the efficacy of factors such as primary wound closure, demographics, and drug holidays in reducing its incidence. The purpose of this study was to retrospectively investigate the relationships between these various risk factors after tooth extraction in patients receiving oral bisphosphonate therapy. METHODS: Risk factors for MRONJ after tooth extraction were evaluated using univariate and multivariate analysis. All patients were investigated with regard to demographics; type and duration of oral bisphosphonate use; whether they underwent a discontinuation of oral bisphosphonates before tooth extraction (drug holiday), and the duration of such discontinuation; and whether any additional surgical procedures (e.g., incision, removal of bone edges, root amputation) were performed. RESULTS: We found that root amputation (OR = 6.64), extraction of a single tooth (OR = 3.70), bone loss or severe tooth mobility (OR = 3.60), and an unclosed wound (OR = 2.51) were significantly associated with increased risk of developing MRONJ. CONCLUSIONS: We recommend a minimally traumatic extraction technique, removal of any bone edges, and mucosal wound closure as standard procedures in patients receiving bisphosphonates. We find no evidence supporting the efficacy of a pre-extraction short-term drug holiday from oral bisphosphonates in reducing the risk of MRONJ.


Asunto(s)
Osteonecrosis de los Maxilares Asociada a Difosfonatos/etiología , Osteonecrosis de los Maxilares Asociada a Difosfonatos/prevención & control , Conservadores de la Densidad Ósea/administración & dosificación , Difosfonatos/administración & dosificación , Extracción Dental/efectos adversos , Técnicas de Cierre de Heridas , Administración Oral , Adulto , Anciano , Anciano de 80 o más Años , Conservadores de la Densidad Ósea/efectos adversos , Difosfonatos/efectos adversos , Esquema de Medicación , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Extracción Dental/métodos , Privación de Tratamiento , Cicatrización de Heridas , Adulto Joven
3.
Cancer Res ; 52(13): 3642-7, 1992 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-1617637

RESUMEN

We developed a new approach for detecting the gene amplification of cancer DNAs with restriction landmark genomic scanning (RLGS). In cancer research, much effort has been made to find the amplified loci of cancer DNAs, because many lines of evidence indicate association between oncogene amplification and carcinogenesis. Conventionally, such gene amplification has been detected by using Southern hybridization with DNA probes. However, only the information of one locus can be obtained by one hybridization procedure, and analysis of many loci throughout the genome is too laborious and time consuming, even if only several candidate genes are investigated. On the other hand, the "in-gel renaturation method" was reported as another alternative for detection of amplified regions. However, even though this method is much improved, it is difficult to detect less than 7-fold amplification, which is often higher than the amplification of many cancer cases. To overcome these limitations and, in addition, to locate the amplified DNA two dimensionally, we applied RLGS for analysis of DNA amplification in cancer tissues, such as breast cancer (infiltrative tubuloadenocarcinoma), neuroblastoma, meningioma (endotheliomatous meningioma), and thyroid cancer (papillary adenocarcinoma). In some cases of breast cancer, several amplified spots located on the same amplicon were detected. In thyroid cancer, in which no amplification has yet been reported, low-grade amplification was also detected. In this report, we demonstrated that RLGS allows us to screen 2000-3000 restriction landmarks distributed on the genome simultaneously, and even low-grade amplification could be detected effectively. Thus, RLGS has proven to be a very useful method in detecting DNA amplification.


Asunto(s)
ADN de Neoplasias/genética , Amplificación de Genes , Neoplasias de la Mama/genética , Humanos , Neuroblastoma/genética
4.
Int J Oral Maxillofac Surg ; 45(9): 1095-9, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27134046

RESUMEN

This retrospective study was performed to investigate the influence of occlusal support and the presence, state, and position of mandibular third molars on the incidence of mandibular angle and condylar fractures. The following variables were investigated: age, sex, cause of fracture, presence and state (impaction, angulation, and the number of roots) of the mandibular third molars, site of the mandibular fracture, presence of occlusal support, duration of intermaxillary fixation, and postoperative complications. Various risk factors for mandibular angle and condylar fractures were investigated by univariate analysis. The risk of mandibular angle fracture was significantly higher in patients with occlusal support and mandibular third molars. The risk of condylar fracture was significantly higher in patients without occlusal support or mandibular third molars. The position and angulation of the mandibular third molars were not significant risk factors in mandibular angle and condylar fractures. This study demonstrated the influence of occlusal support and the presence of mandibular third molars on the incidence of mandibular angle and condylar fractures. The presence of occlusal support may be a more important factor affecting mandibular angle or condylar fractures than the position of the mandibular third molars.


Asunto(s)
Oclusión Dental , Cóndilo Mandibular/lesiones , Fracturas Mandibulares/etiología , Tercer Molar/anatomía & histología , Diente Impactado/complicaciones , Adolescente , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Humanos , Incidencia , Masculino , Fracturas Mandibulares/epidemiología , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Adulto Joven
5.
Int J Oral Maxillofac Surg ; 34(7): 739-44, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15921890

RESUMEN

The treatment method for early stage tongue cancer is still controversial in Japan. The aim of this study is to compare the prognosis for patients with early tongue cancer treated with brachytherapy and surgery. A retrospective study was conducted to compare the efficacy of low-dose-rate brachytherapy (LDR), high-dose-rate brachytherapy (HDR), and surgery for early tongue cancer. A total of 180 patients with stage I-II tongue cancer were divided into three treatment groups: LDR (78), HDR (26), and surgery (71). Local recurrence was seen in thirteen patients (17%) of the LDR, nine (35%) of the HDR, and four (6%) of the surgery group. After salvage therapy, final local cure was obtained for 71 patients (91%) of the LDR, 22 (85%) of the HDR, and 71 (100%) of the surgery group. Neck failure was recorded for eight patients in the LDR, six in the HDR, and three in the surgery group. The respective 5-year overall survival rates for the LDR, HDR and surgery groups were 84.0%, 72.9%, 95.4% for stage I, and 72.2%, 51.5%, 93.8% for stage II. These findings show that surgery is the optimal treatment method for patients with stage I-II tongue cancer.


Asunto(s)
Braquiterapia/métodos , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirugía , Neoplasias de la Lengua/radioterapia , Neoplasias de la Lengua/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Femenino , Humanos , Terapia por Láser , Metástasis Linfática , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Pronóstico , Dosificación Radioterapéutica , Estudios Retrospectivos , Análisis de Supervivencia , Neoplasias de la Lengua/patología
6.
DNA Res ; 3(2): 87-92, 1996 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-8804860

RESUMEN

N-Terminally truncated DNA polymerase from Thermus thermophilus (delta Tth polymerase) lacking 5'-3' exonuclease activity was used for DNA sequencing and polymerase chain reaction (PCR). In contrast to the high background of the sequencing ladder observed with the wild-type Tth polymerase, delta Tth polymerase gave readable sequencing patterns which extend up to more than 500 bases from the primer site on cycle sequencing and automated sequencing. The delta Tth polymerase was used for the standard and mutagenic PCR, and net amplification of the DNA and the mutations accumulated during PCR were analyzed. Under mutagenic PCR, the mutation rates were 7.0 x 10(-4) (Tth) and 8.3 x 10(-4) (delta Tth) per nucleotide per cycle of amplification, which were 4-9 times higher than the rates under standard PCR.


Asunto(s)
ADN Polimerasa Dirigida por ADN/química , Reacción en Cadena de la Polimerasa/métodos , Análisis de Secuencia de ADN/métodos , Thermus thermophilus/enzimología , Automatización , ADN Polimerasa Dirigida por ADN/metabolismo , Mutagénesis , Mutación
7.
Oral Oncol ; 38(4): 378-82, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12076703

RESUMEN

Most carcinomas of upper gingiva and hard palate are classified as T4 stage on the basis of the UICC criteria, since they easily invade the underlying bone tissue. We classified 43 patients with squamous cell carcinoma of the upper gingiva in terms of three criteria: (1) the original T-classification by UICC, (2) the classification by the Japan Society for Head and Neck Cancer (JSHNC), and (3) a new classification in which the maxillary sinus or nasal floor is used as the defining borderline for T4 (MSF classification). Our study demonstrated that the new classification was superior with regard to distribution of patients by T stage, correlation with prognosis and choice of treatment method.


Asunto(s)
Carcinoma de Células Escamosas/clasificación , Neoplasias Gingivales/clasificación , Neoplasias Palatinas/clasificación , Carcinoma de Células Escamosas/cirugía , Neoplasias Gingivales/cirugía , Humanos , Imagen por Resonancia Magnética , Neoplasias Palatinas/cirugía , Análisis de Supervivencia , Tomografía Computarizada por Rayos X
8.
Oral Oncol ; 38(1): 30-4, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11755818

RESUMEN

Adenoid cystic carcinoma (ACC) is a rare malignant tumour of the head and neck occurring in the salivary glands. We established a human ACC line which is serially transplantable in nude mice and designated it as KOA-1. The KOA-1 tumour doubled in 9.3 days and retained the histological characteristics of a solid pattern of ACC even after 22 serial passages. The KOA-1 metastasised to the lung when transplanted subcutaneously into the back. This tumour line may serve as a useful model for exploration of the biological behaviour and treatment of human ACC.


Asunto(s)
Carcinoma Adenoide Quístico/secundario , Neoplasias Pulmonares/secundario , Trasplante de Neoplasias/métodos , Neoplasias de las Glándulas Salivales/patología , Animales , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Microscopía Electrónica , Persona de Mediana Edad , Neoplasias de la Lengua/patología , Células Tumorales Cultivadas
9.
Artículo en Inglés | MEDLINE | ID: mdl-11077395

RESUMEN

OBJECTIVE: This retrospective clinical study evaluated the usefulness of high-dose rate (HDR) brachytherapy for stage I-II tongue cancer in comparison with traditional low-dose rate (LDR) brachytherapy. MATERIALS AND METHODS: Twenty-five patients with stage I-II tongue cancer underwent HDR between 1995 and 1999. The status of local control and late neck metastasis, survival rate, and frequency of osteonecrosis in these patients were examined in comparison with a historical control made up of 71 patients who underwent LDR between 1980 and 1995. RESULTS: The local control rate and survival rate were lower in the HDR group than in the LDR group. There were no apparent differences in the frequency of late neck metastasis between the two groups. Osteonecrosis occurred earlier and more frequently in the HDR group. CONCLUSION: We would caution the use of HDR brachytherapy until further studies are done in many institutions.


Asunto(s)
Braquiterapia/métodos , Neoplasias de la Lengua/radioterapia , Braquiterapia/efectos adversos , Femenino , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Osteorradionecrosis/etiología , Pronóstico , Dosificación Radioterapéutica , Estudios Retrospectivos , Análisis de Supervivencia , Neoplasias de la Lengua/patología
10.
Int J Vitam Nutr Res ; 61(4): 325-7, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1806537

RESUMEN

The possible biosynthesis of ascorbic acid 2-sulfate (AsS) in rat was investigated. A in vivo test was conducted according to Mumma and Mohamram. 10 mumoles ascorbic acid (AsA) and 25 mu Ci35SO4(2-) were injected intraperitoneally into rats once a day for four days. 24 hours after the final administration, the animals were sacrificed and the liver, kidneys and urine were collected. The result did not confirm the biosynthesis of AsS under the test conditions, though there appeared the possibility of the biosynthesis of a trace amount of AsS too small to permit detection.


Asunto(s)
Ácido Ascórbico/análogos & derivados , Animales , Ácido Ascórbico/biosíntesis , Ácido Ascórbico/orina , Riñón/metabolismo , Hígado/metabolismo , Masculino , Ratas , Ratas Endogámicas
11.
Int J Vitam Nutr Res ; 63(3): 208-11, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8300332

RESUMEN

L-threo-hex-2-enaro-1,4-lactone ethyl ester (II) was synthesized by the modified Fisher's esterification and its sodium salt was obtained almost quantitatively. Confirmation of the compound was made by elementary analysis, as well as IR, UV, MS and NMR spectra. The antiscorbutic activity was compared to that of ascorbic acid and the result showed that (II) did not have Vitamin C activity. The results of this investigation indicate that a close relationship exists between the chemical structure of the C-6 position of ascorbic acid analogues and the development of vitamin C activity.


Asunto(s)
Ácido Ascórbico/análogos & derivados , Ácido Ascórbico/uso terapéutico , Escorbuto/tratamiento farmacológico , Fosfatasa Alcalina/sangre , Animales , Ácido Ascórbico/síntesis química , Ácido Ascórbico/metabolismo , Ácido Ascórbico/farmacocinética , Ácido Ascórbico/farmacología , Peso Corporal/efectos de los fármacos , Química Encefálica , Cobayas , Hidroxiprolina/sangre , Riñón/química , Hígado/química , Masculino
12.
Int J Oral Maxillofac Surg ; 40(6): 593-6, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21334851

RESUMEN

Oral squamous cell carcinoma (OSCC) is often surrounded by epithelial dysplasia; leaving it unresected can result in local recurrence. Staining with Lugol's iodine solution detects epithelial dysplasia in oral mucosa, but whether it decreases local recurrence after OSCC surgery is unknown. This study investigated local recurrence rates in patients with early tongue cancer who underwent surgery using Lugol's staining. 93 patients with T1-2N0 tongue SCC underwent partial glossectomy using Lugol's staining during surgery. Resection was performed at least 5mm from the margin of the unstained area. Patients were investigated retrospectively for local recurrence status. Postoperative histology revealed negative surgical margins for SCC or epithelial dysplasia in 81 patients, close margins for SCC in 5, positive margins for mild epithelial dysplasia in 6, and a positive margin for SCC in one. Those with a positive or a close margin for SCC underwent additional resection 2-4 weeks after surgery; one was proved histologically to have residual SCC. No patients developed local recurrence, but 2 died of neck metastasis and 2 of distant metastasis. The 5-year disease specific survival rate was 93.8%. Lugol's staining during surgery can reduce local recurrence and improve survival in patients with early tongue SCC.


Asunto(s)
Carcinoma de Células Escamosas/cirugía , Colorantes , Yoduros , Neoplasias de la Lengua/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/secundario , Supervivencia sin Enfermedad , Epitelio/patología , Femenino , Estudios de Seguimiento , Glosectomía/métodos , Humanos , Metástasis Linfática/patología , Masculino , Persona de Mediana Edad , Disección del Cuello , Recurrencia Local de Neoplasia/prevención & control , Estadificación de Neoplasias , Neoplasia Residual/cirugía , Lesiones Precancerosas/patología , Reoperación , Estudios Retrospectivos , Tasa de Supervivencia , Neoplasias de la Lengua/patología
13.
Biochem Biophys Res Commun ; 200(1): 584-90, 1994 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-8166733

RESUMEN

We analyzed the nucleotide sequence of the luteinizing hormone beta subunit (LH beta) in a patient with an anomalous LH. This anomalous LH showed abnormal immunogenicity, but normal bioactivity, suggesting that this variance of antigenicity was caused by amino acid substitution(s). In the anomalous LH, two single amino acid substitutions, Trp(TGG) to Arg(CGG) and Ile(ATC) to Thr(ACC), were found at the codon for the 8th and 15th residue of LH beta. These two substituted amino acid residues of the anomalous LH are identical to those of chorionic gonadotropin, but not to those of LH, although the rest of the region showed the normal sequence of human LH beta. Pedigree analysis by direct DNA sequencing revealed that the parents of the patient and the healthy sister were heterozygotes for the mutation and the patient and the healthy brother were homozygotes.


Asunto(s)
Gonadotropina Coriónica/genética , Variación Genética , Hormona Luteinizante/genética , Mutación Puntual , Aborto Habitual , Adulto , Anciano , Secuencia de Aminoácidos , Antígenos/genética , Secuencia de Bases , Clonación Molecular , ADN/sangre , ADN/aislamiento & purificación , Cartilla de ADN , Femenino , Heterocigoto , Homocigoto , Humanos , Leucocitos/metabolismo , Hormona Luteinizante/inmunología , Masculino , Datos de Secuencia Molecular , Linaje , Reacción en Cadena de la Polimerasa , Embarazo , Mapeo Restrictivo
14.
Proc Natl Acad Sci U S A ; 88(21): 9523-7, 1991 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-1946366

RESUMEN

We have developed a powerful genomic scanning method, termed "restriction landmark genomic scanning," that is useful for analysis of the genomic DNA of higher organisms using restriction sites as landmarks. Genomic DNA is radioactively labeled at cleavage sites specific for a rare cleaving restriction enzyme and then size-fractionated in one dimension. The fractionated DNA is further digested with another more frequently occurring enzyme and separated in the second dimension. This procedure gives a two-dimensional pattern with thousands of scattered spots corresponding to sites for the first enzyme, indicating that the genome of mammals can be scanned at approximately 1-megabase intervals. The position and intensity of a spot reflect its locus and the copy number of the corresponding restriction site, respectively, based on the nature of the end-labeling system. Therefore, this method is widely applicable to genome mapping or detection of alterations in a genome.


Asunto(s)
Mapeo Restrictivo , Animales , Mapeo Cromosómico , Clonación Molecular , Drosophila melanogaster/genética , Electroforesis en Gel Bidimensional , Heterocigoto , Proyecto Genoma Humano , Humanos
15.
Cancer Detect Prev ; 17(3): 399-404, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8402726

RESUMEN

Restriction Landmark Genomic Scanning (RLGS) was used to examine the multiple alterations of genomic DNAs that occur in association with transformation and development of malignancy in primary hepatocellular carcinoma (HCC). Genomic DNAs from HCC and its normal counterpart were cleaved by the restriction enzyme NotI, radiolabeled at the cleavage sites, and then size-fractionated by two-dimensional electrophoresis using HinfI as the second cleavage enzyme. About 2000 spots were recognized, whose position and intensity reflect the locus and the copy number of the corresponding restriction sites. Using this system in combination with micromanipulation of HCC to eliminate possible carry-over of nonmalignant cells, we detected six spots that were decreased in intensity in common to three different HCCs, along with five that were intensified spots. In addition, several spots showed changes that were nonoverlapping among different tumors.


Asunto(s)
Carcinoma Hepatocelular/genética , ADN de Neoplasias/genética , Neoplasias Hepáticas/genética , Mapeo Restrictivo , Electroforesis en Gel Bidimensional , Humanos
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