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1.
Oxid Med Cell Longev ; 2022: 2422618, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35186182

RESUMO

The vermilion of the human lip, covered by a skinny epithelium with little melanin, is quite susceptible to damage from ultraviolet (UV) radiation exposure. However, commercial sunscreen filters and indelible dyes used in lipsticks can cause health hazards after percutaneous absorption or accidentally oral administration. Inspired by plant pigmentation as natural filters to protect themselves against overexposure to UV, safer bio-based sunscreens of cellulose enveloped with anthocyanin (AN) were developed using bionic design. Cellulose nanocrystals (CNC), derived from acid hydrolysis of cellulose, reinforced enhancement of UV absorption and shielding properties of AN. This innovation addresses the issue that naturally sourced UV filter application to sunscreen does not achieve a desired sun protection factor (SPF) value because of the low specific extinction value (E1,1). We also stated that the diverse formula of anthocyanin sunscreen lipsticks with CNC exhibited 10 times more SPF value than AN alone. Furthermore, they possess competitive benefits such as pleasing texture, superior adhesion, impermeable, nonphototoxicity, ease of application, and removal. This work provides a promising proof-of-concept for studying the features of natural sunscreens in the design of simple, safe, efficient, and green sunscreens.


Assuntos
Celulose/metabolismo , Corantes/efeitos adversos , Lábio/efeitos da radiação , Nanopartículas/metabolismo , Fator de Proteção Solar/métodos , Animais , Humanos , Camundongos
2.
Technol Cancer Res Treat ; 20: 15330338211019511, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34044671

RESUMO

OBJECTIVE: In this study, by comparing coplanar and noncoplanar intensity-modulated radiation therapy (IMRT) treatment planning in treating tongue cancer, the significance of noncoplanar fields in the protection of the lip and buccal mucosa was determined, and a reasonable solution was selected. METHODS: Forty-eight tongue cancer patients treated from June 2019 to February 2021 were selected and randomly divided into a coplanar field group and a noncoplanar field group. The mucosal dose limit changed from 15 Gy to 45 Gy for comparison of the two treatment plans. The evaluation indicators (conformal index (CI); homogeneity index (HI); D5, D50, and D98 of the target volume; and the dose of normal tissues) were calculated under different mucosal dose limits. The clinical observation of the lip and buccal mucosa of 48 cases was monitored and graded carefully according to NCI-CTCAE V4.0. Statistical analyses were performed. RESULTS: The differences in CI, HI, D98, D50 and D5 between the two groups in the target volume tended to decrease when the mucosal dose limit was less than 30 Gy, with a significant difference (P < 0.05). When the limit exceeded 30 Gy, significant differences in other indicators except CI (P < 0.05) were still noted. In normal tissue, differences in doses between the two groups existed when the mucosal limit was less than 20 Gy, with a significant difference (P < 0.05). When the limit exceeded 20 Gy, no significant difference was noted. Patients in the noncoplanar group showed significantly better results than those in the other group in terms of the radiation-related toxicity of the lip and cheek membrane(P < 0.001). CONCLUSIONS: Compared with coplanar field radiotherapy, noncoplanar field radiotherapy can effectively reduce the exposure dose to the lip and buccal mucosa. The application of noncoplanar treatment plans exhibits good clinical significance and deserves to be promoted.


Assuntos
Lábio/efeitos da radiação , Mucosa Bucal/efeitos da radiação , Tratamentos com Preservação do Órgão/métodos , Órgãos em Risco/efeitos da radiação , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Neoplasias da Língua/radioterapia , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Dosagem Radioterapêutica , Neoplasias da Língua/patologia
3.
Lasers Med Sci ; 35(1): 165-171, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31177406

RESUMO

Lip hyperpigmentation is an esthetic problem. Clinical data from controlled comparative studies is insufficient to support the efficacy of laser treatments for hyperpigmented lips. This study is aimed to compare the efficacy of low-fluence Q-switched Nd:YAG 1064-nm laser (LFQS 1064-nm) versus Q-switched Nd:YAG 532-nm laser (QS 532-nm) for the treatment of hyperpigmented lips. A randomized, controlled, evaluator-blinded study was conducted in thirty subjects. They were randomized into 2 groups. The first group was treated with five treatment sessions with a 2-week interval of LFQS 1064-nm laser while the second group was treated with a single session of QS 532-nm laser. The evaluation was conducted at baseline, 2 weeks of each post treatment, and 4 weeks after the last treatment session. The efficacy was assessed by melanin index, Methuen colored plate, photographic evaluation, pain score, patient's satisfaction, and patient's Dermatology Life Quality Index. The adverse effects were also recorded. All patients attained throughout the study protocol. The most frequent fluence applied was 2.4 J/cm2 (2.2-2.5 J/cm2) and 2.0 J/cm2 (1.7-2.4 J/cm2) in the LFQS 1064-nm group and QS 532-nm group, respectively. The results of the QS 532-nm group showed greater percentage of melanin index reduction and better average mean of photographic evaluation percentage changes from the baseline than the LFQS 1064-nm group (p < 0.001 and p < 0.001, respectively). The adverse effects were less likely to occur in the LFQS 1064-nm group. Few cases of scale, hypopigmentation, bleb formation, postinflammatory hyperpigmentation, and labial edema occurred only in the QS 532-nm group.


Assuntos
Hiperpigmentação/radioterapia , Lasers de Estado Sólido/uso terapêutico , Lábio/efeitos da radiação , Adulto , Feminino , Humanos , Hiperpigmentação/metabolismo , Lábio/metabolismo , Masculino , Satisfação do Paciente , Estudos Prospectivos , Resultado do Tratamento
4.
J Cosmet Dermatol ; 18(6): 1672-1674, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30964234

RESUMO

INTRODUCTION: Lip darkening is a relatively common condition, especially in the Middle East and Southeast Asia. It is well documented in the literature and generally considered to be multifactorial. The presentation can be physiologic or pathologic and caused by a variety of local or systemic factors. CASE PRESENTATION: A 32-year-old female with skin type IV presented to the clinic with concerns of darkening lips with no associated symptoms or history of disease. On examination, her lips were homogenously dark brown with the upper lip slightly darker than the lower lip. OBJECTIVE: To report effectivness of Q-switched 532 nm laser for treatment of lip pigmentation. METHOD: Topical 2.5% lidocaine/prilocaine (EMLA) cream was applied 30 minutes prior to laser therapy. The region was treated with Q-switched 532 nm laser (Medlite). RESULT: Two weeks after laser treatment , threre was satisfying subjective and objective improvment in lip pigmnetation. CONCLUSION: Q-Switched 532 nm laser effectively reduces lip pigmentation after one session with minimal adverse effects and lasting results.


Assuntos
Hiperpigmentação/radioterapia , Lasers de Estado Sólido/uso terapêutico , Lábio/efeitos da radiação , Terapia com Luz de Baixa Intensidade/métodos , Adulto , Feminino , Humanos , Hiperpigmentação/diagnóstico por imagem , Terapia com Luz de Baixa Intensidade/instrumentação , Fotografação , Resultado do Tratamento
6.
Photodiagnosis Photodyn Ther ; 14: 170-2, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27102062

RESUMO

Due to the unique location of the squamous cell carcinoma (SCC) of the lip, using a single method such as extended resection or radiotherapy probably causes morphological and functional defects. So we used surgery combined with topical photodynamic therapy (PDT) to treat SCC of the lip. Under local anesthesia with 5% lidocaine, the hyperplastic and ulcerative SCC of the lip were curetted and assisted by topical PDTs after surgery. The 20% 5-aminolevulinic acid cream was used as a photosensitizer and applied evenly to the surface of the tumor lesion for 4h. Then the lesion site was irradiated with a 635-nm laser at 120J/cm(2). A total of five PDTs were performed postoperatively at an interval of 2 weeks. Photos were taken before and after every PDT to compare the skin lesions, treatment effects, and side effects. A long-term follow-up was undertaken to observe tumor recurrence. After surgery combined with five topical PDTs, the SCC of the lip disappeared without the compromised morphology of the lip, significant side effects, or tumor recurrence in one-year follow-up. Surgery combined with topical PDT can reduce the excision size of tumors and play a positive role in the treatment of tumors of special locations.


Assuntos
Carcinoma de Células Escamosas/terapia , Lábio/patologia , Fotoquimioterapia , Neoplasias Cutâneas/terapia , Adulto , Ácido Aminolevulínico/administração & dosagem , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Seguimentos , Humanos , Lábio/efeitos da radiação , Masculino , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia
7.
J Contemp Dent Pract ; 15(1): 8-11, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24939257

RESUMO

OBJECTIVE AND BACKGROUND: One of the most significant side effects of radiotherapy for head and neck cancers is xerostomia as a result of salivary gland damage. Considering pharmaco- logical effects of propolis, we evaluated its protective effect on salivary glands subjected to radiotherapy of head and neck cancer patients. MATERIALS AND METHODS: Twenty-one male albino rats (8-11 W, 190 ± 5 gm) were divided into three groups of seven animals. Scintigraphy was performed in all the groups. Then groups 1 (S) and 2 (SR) received normal saline injections and group 3 (PR) received propolis injection over 3 days. After that groups 2 and 3 were exposed to gamma radiation and all the rats underwent scintigraphic assessment on third day and 70th day after irradiation. The lips and tongues of rats in groups 2 and 3 were examined for mucositis daily in first 10 days. At the end, the parotid glands of all rats were examined histologically. RESULTS: Scintigraphy results of third and 70th day after irradiation showed statistically significant differences between PR and SR as well as SR and S. However, there was no significant difference between the PR and S groups. Histopathologic assessment demonstrated significant difference between SR, PR and S. CONCLUSION: These results suggest that propolis has protective effects on salivary gland function in animal models whilst it did not prevent radiation-induced histologic changes in tissues. Further investigations are needed to elucidate mechanisms of propolis actions. Clinical significance: Regarding to the results of this study, propolis may be useful in reduction xerostomia due to radiation to salivary glands and may be helpful for head and neck cancer patients.


Assuntos
Raios gama/efeitos adversos , Glândula Parótida/efeitos da radiação , Própole/uso terapêutico , Protetores contra Radiação/uso terapêutico , Adipócitos/patologia , Adipócitos/efeitos da radiação , Animais , Células do Tecido Conjuntivo/patologia , Células do Tecido Conjuntivo/efeitos da radiação , Avaliação Pré-Clínica de Medicamentos , Lábio/efeitos da radiação , Masculino , Modelos Animais , Tamanho do Órgão , Glândula Parótida/diagnóstico por imagem , Glândula Parótida/efeitos dos fármacos , Cintilografia , Ratos , Ratos Wistar , Ductos Salivares/patologia , Ductos Salivares/efeitos da radiação , Estomatite/etiologia , Fatores de Tempo , Língua/efeitos da radiação , Xerostomia/etiologia
8.
Aust Dent J ; 55 Suppl 1: 78-84, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20553248

RESUMO

Actinic cheilitis is a potentially premalignant condition involving predominantly the vermilion of the lower lip. The aim of the current paper was to review the clinical presentation of actinic cheilitis and demonstrate the development of management plans using a series of cases. These are designed to provide immediate treatment where required but also to address the medium and long-term requirements of the patient. The authors suggest that the clinical examination of lips and the assessment of actinic cheilitis and other lip pathology become a regular part of the routine soft tissue examination undertaken as a part of the periodic examination of dental patients. Early recognition of actinic cheilitis can allow the development of strategies for individual patients that prevent progression. These are based on past sun exposure, future lifestyle changes and the daily use of emollient sunscreens, broad-brimmed hats and avoidance of sun exposure during the middle of the day. This is a service that is not undertaken as a matter of routine in general medical practice as patients are not seen with the regularity of dental patients and generally not under the ideal examination conditions available in the dental surgery.


Assuntos
Queilite/diagnóstico , Luz Solar/efeitos adversos , Adolescente , Diagnóstico Diferencial , Progressão da Doença , Feminino , Humanos , Leucoplasia Oral/diagnóstico , Estilo de Vida , Lábio/efeitos da radiação , Neoplasias Labiais/diagnóstico , Masculino , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação/diagnóstico , Lesões Pré-Cancerosas/diagnóstico , Roupa de Proteção , Protetores Solares/uso terapêutico
9.
Radiother Oncol ; 93(3): 545-52, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19853316

RESUMO

BACKGROUND AND PURPOSE: It is believed that minimizing inconsistencies in OAR-volume definition will help to improve adequate reporting and interpreting of radiation treatment results. The aim of this paper is to introduce computed tomography (CT)-based delineation guidelines for organs at risk (OARs) in the head and neck area, associated with radiation-induced salivary dysfunction and xerostomia. MATERIAL AND METHODS: After analyses of the human anatomy of the head and neck area, computed tomography (CT)-based guidelines for delineation of the most relevant OARs were described by a panel of experts. RESULTS AND CONCLUSIONS: The provided OAR guidelines are accompanied by CT-based illustrations presenting examples of the delineated structures and their corresponding anatomic boundaries. The parts of the tongue bearing minor salivary glands could not be outlined. Difficulties and uncertainties in defining these minor salivary glands on CT remain to be resolved. Implementation of these guidelines in practice should lead to a reduction in inter- and intra-observer variability and therefore unambiguous reporting of possible dose-volume effect relationships.


Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Glândulas Salivares/efeitos da radiação , Xerostomia/etiologia , Bochecha/efeitos da radiação , Humanos , Lábio/efeitos da radiação , Palato Mole/efeitos da radiação , Doses de Radiação , Lesões por Radiação , Glândulas Salivares/metabolismo , Sialografia , Tomografia Computadorizada por Raios X , Xerostomia/diagnóstico por imagem
10.
Int J Radiat Oncol Biol Phys ; 74(4): 1242-50, 2009 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-19545790

RESUMO

PURPOSE: Oral mucositis is a common side effect induced by radio/chemotherapy in patients with head and neck cancer. Although it dramatically impairs patient quality of life, no efficient and safe therapeutic solution is available today. Therefore, we investigated the protective efficacy of a new heparan mimetic biopolymer, RGTA-OTR4131, used alone or in combination with amifostine, for oral mucositis and simultaneously evaluated its effect on tumor growth in vitro and in vivo. METHODS AND MATERIALS: A single dose of 16.5 Gy was selectively delivered to the snout of mice, and the effects of OTR4131 or amifostine-OTR4131 were analyzed by macroscopic scoring and histology. The effect of OTR4131 administration on tumor growth was then investigated in vitro and in xenograft models using two cell lines (HEP-2 and HT-29). RESULTS: Amifostine and OTR4131 significantly decreased the severity and duration of lip mucosal reactions. However, amifostine has to be administered before irradiation, whereas the most impressive protection was obtained when OTR4131 was injected 24 h after irradiation. In addition, OTR4131 was well tolerated, and the combination of amifostine and OTR4131 further enhanced mucosal protection. At the tumor level, OTR4131 did not modify HEP-2 cell line clonogenic survival in vitro or protect xenografted tumor cells from radiotherapy. Of interest, high doses of OTR4131 significantly decreased clonogenic survival of HT-29 cells. CONCLUSIONS: RGTAs-OTR4131 is a well-tolerated, natural agent that effectively reduces radio-induced mucositis without affecting tumor sensitivity to irradiation. This suggests a possible transfer into the clinic for patients' benefit.


Assuntos
Amifostina/uso terapêutico , Glucanos/uso terapêutico , Lábio/efeitos da radiação , Lesões Experimentais por Radiação/prevenção & controle , Protetores contra Radiação/uso terapêutico , Estomatite/prevenção & controle , Amifostina/administração & dosagem , Animais , Linhagem Celular Tumoral , Esquema de Medicação , Quimioterapia Combinada , Feminino , Glucanos/administração & dosagem , Células HT29 , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Doses de Radiação , Protetores contra Radiação/administração & dosagem , Distribuição Aleatória , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
11.
Logoped Phoniatr Vocol ; 33(1): 49-64, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18344143

RESUMO

The study of the glottal flow, the acoustic excitation for voiced speech, provides insight into the voice signal, which is of potential benefit in many disciplines. One common method for estimating the glottal flow is inverse filtering, in which the effects of the vocal tract and the lip radiation are removed from a microphone signal. This paper presents a new inverse filtering and parameterization software package, which is available under an open-source licence. It provides a user-friendly graphical interface for rapid inverse filtering and parameterization, and the algorithms and parameters can be easily re-used in other projects. The system has already proved to be useful in algorithm development, speech science research, as well as in the study of occupational voice.


Assuntos
Glote/fisiologia , Qualidade da Voz , Voz/fisiologia , Eletrofisiologia/instrumentação , Desenho de Equipamento , Humanos , Laringe/efeitos da radiação , Lábio/efeitos da radiação , Ocupações , Fonética , Acústica da Fala
12.
Oral Oncol ; 44(9): 878-83, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18234540

RESUMO

The p53 pathway is commonly altered during oral and skin carcinogenesis. The lip is a transition tissue between skin and oral mucosa, which in response to UVB exposure also exhibits alterations in the expression of p53 and p53-related genes that could lead to malignant transformation. To assess if the p53-regulated proteins murine-double-minute (mdm)-2 and p21 are altered during early lip carcinogenesis, biopsies from normal lip (n=16) and the premalignant lip lesion, actinic cheilitis (AC) (n=26) were processed for the immunohistochemical detection of p53, p21 and mdm-2 in serial co-localized sections. Epithelial co-expression of p53 and mdm-2 was significantly increased in AC as compared to normal lip (P<0.001). No differences in epithelial p21 expression were found between normal lip and AC. While in normal lip mdm-2 and p21 were significantly correlated with p53, in AC only mdm-2 was associated with p53 expression. Multivariate logistic regression analysis of the three markers (Wald stepwise) showed that p53 is the only predictor of AC. The results point to alterations in the p53 pathway during early lip carcinogenesis, highlighting p53 as a potential marker of early malignancy of the lip.


Assuntos
Biomarcadores Tumorais/metabolismo , Queilite/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Neoplasias Labiais/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Adulto , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Queilite/patologia , Feminino , Humanos , Lábio/metabolismo , Lábio/patologia , Lábio/efeitos da radiação , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/metabolismo , Mucosa Bucal/patologia , Análise de Regressão , Raios Ultravioleta/efeitos adversos , Adulto Jovem
13.
Clin Neurophysiol ; 118(4): 794-801, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17307387

RESUMO

OBJECTIVE: To describe the reflex responses evoked by trigeminal stimulation in perioral facial motor units (MUs) in humans. METHODS: We recorded single motor units (MUs) from perioral muscles performing three movements: elevation of the upper lip (levator labii superioris muscle--LLS), protrusion of the lips (orbicularis oris muscle--OOr) and depression of the lower lip (depressor anguli oris and depressor labii inferioris muscles--DAO/DLI) with concentric needle electrodes. MUs were tested during constant voluntary activation with non-painful cutaneous electrical stimuli applied to the mental or supraorbital nerves and intraorally. Analysis was performed with peristimulus histograms and cumulative sum. RESULTS: Eighty MUs were sampled from 17 subjects. Cutaneous stimulation induced inhibition of discharge in 100% of the lip-depressor MUs, inhibition in 65-70% of LLS MUs and in 25% of OOr MUs. Mean latency of inhibition was of 35+/-12ms. Intraoral stimulation produced an equivalent percentage of inhibitory or facilitatory effects with no difference among the three muscles. CONCLUSIONS: Reflex responses to cutaneous stimulation identify a completely inhibitory (DAO/DLI), a mainly inhibitory (LLS) and a mixed (OOr) pattern in perioral muscles. SIGNIFICANCE: A purely inhibitory trigemino-facial reflex is present in lip-lowering muscles with potential use in clinical practice.


Assuntos
Músculos Faciais/inervação , Nervo Facial/fisiologia , Inibição Neural/fisiologia , Reflexo/fisiologia , Adulto , Relação Dose-Resposta à Radiação , Eletromiografia/métodos , Músculos Faciais/fisiologia , Feminino , Humanos , Lábio/fisiologia , Lábio/efeitos da radiação , Masculino , Reflexo/efeitos da radiação , Nervo Trigêmeo/fisiologia
14.
Dermatology ; 203(3): 244-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11701980

RESUMO

BACKGROUND AND OBJECTIVE: There is a well-documented need for effective human UVA and UVB photoprotection. Since there are important anatomical variations, the sun protection factor (SPF) of a lipstick sunscreen was measured on the anatomical site intended for use. METHODS: The SPF tests were performed according to Federal US and European COLIPA guidelines. Prior to performing a test on the lip, the minimal erythemal dose (MED) of the unprotected back skin was determined. Subsequently, the sunscreen SPF was measured on the anatomical target site (lip). The evaluator was blinded with respect to scoring the SPF of each sunscreen treatment. Individual test sites were assigned to one of the following treatment conditions: (1) no treatment (MED of unprotected skin); (2) test formulation; (3) reference standard. RESULTS: The MED on unprotected back skin was found to be 25% lower than on unprotected lip skin. The SPF of the lipstick sunscreen was measured 2 units lower than the SPF determined in the classical way on the back skin. CONCLUSION: It was hypothesized that the higher MED of the lower lip compared with back skin was due to the adaptation of this tissue to the continuous exposure to UV radiation.


Assuntos
Cosméticos/farmacologia , Lábio/efeitos dos fármacos , Lábio/efeitos da radiação , Luz Solar , Protetores Solares/farmacologia , Humanos
15.
Int J Radiat Oncol Biol Phys ; 47(3): 785-91, 2000 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10837965

RESUMO

PURPOSE: Gemcitabine (2'2'-difluoro-2'-deoxycytidine, dFdCyd) is a potent radiosensitizer of rodent and human tumor cells. Our Phase I clinical trial using once-weekly dFdCyd as a radiosensitizer in the treatment of patients with Stage IV squamous cell head and neck cancer has produced a high rate of tumor response and significant normal mucosal toxicity. These findings raised the question of whether we are using dFdCyd in the optimal dose and schedule. In vitro studies suggest that twice-weekly dFdCyd has the potential to be more effective than once-weekly dFdCyd when administered in combination with radiation (RT) given 5 days per week. Therefore, we have used a mouse model to assess whether the therapeutic ratio of combined modality therapy may be improved by using a twice-weekly drug regimen. We asked two questions: 1) Does a once-weekly or twice-weekly dFdCyd regimen cause more normal tissue radiosensitization? 2) Does a once-weekly or twice-weekly dFdCyd + RT regimen produce a better therapeutic index? METHODS AND MATERIALS: To assess normal tissue toxicity, C3H mice underwent mouth (60)Co RT (27.5 Gy in 5 daily fractions) +/- dFdCyd delivered intraperitoneally (IP) either once or twice weekly 6 hours prior to irradiation. Acute lip reactions were quantified according to a standard scoring system, and weight loss was measured. We measured tumor control using squamous cell carcinoma (SCC) VII murine squamous cell flank tumors (50-125 mm(3)) treated with the same regimens used in the mouth irradiation model. RESULTS: We found that dFdCyd delivered 800 mg/kg once weekly or 150 mg/kg twice weekly caused similar (and maximal tolerable) weight loss; therefore these regimens were chosen to test which schedule produced more acute lip radiosensitization. Twice-weekly dFdCyd + RT was somewhat more toxic by weight loss (800 mg/kg once weekly: 11.9%; 150 mg/kg twice weekly: 17.7%; p = 0.09). To assess therapeutic index, we treated SCC VII flank tumors with RT combined with isotoxic drug/RT regimens (dFdCyd 800 mg/kg once weekly or 100 mg/kg twice weekly). Tumors treated with twice-weekly dFdCyd + RT were significantly smaller than tumors treated with once-weekly drug + RT at 28 days from the start of treatment (p < 0.03). CONCLUSIONS: These findings demonstrate that equitoxic once- versus twice-weekly dFdCyd regimens cause differing levels of oral mucosal radiosensitization. This would suggest that each radiation-dFdCyd schedule will require its own dFdCyd dose escalation trial (which cannot be determined by the maximum tolerated dose (MTD) for dFdCyd alone using that schedule). In addition, our findings suggest that for head and neck cancers twice-weekly dFdCyd may have a higher therapeutic index compared with once-weekly dFdCyd when combined with daily RT.


Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Desoxicitidina/análogos & derivados , Mucosa Bucal/efeitos dos fármacos , Mucosa Bucal/efeitos da radiação , Radiossensibilizantes/administração & dosagem , Redução de Peso , Animais , Peso Corporal/efeitos dos fármacos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Terapia Combinada , Desoxicitidina/administração & dosagem , Relação Dose-Resposta à Radiação , Esquema de Medicação , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Lábio/efeitos dos fármacos , Lábio/efeitos da radiação , Camundongos , Camundongos Endogâmicos C3H , Tolerância a Radiação , Gencitabina
16.
Radiother Oncol ; 42(2): 189-96, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9106929

RESUMO

BACKGROUND AND PURPOSE: The aim of this study was to evaluate the biological equivalence of continuous low dose rate (LDR) irradiations to multifractionated high dose rate (HDR) regimes. The applicability of the LQ model was analysed for fraction sizes and dose rates relevant for the clinic. MATERIAL AND METHODS: Investigations were performed in mouse lip mucosa. HDR fractions were given in an overall treatment time ranging from 10 h to 3.5 days. The dose rate effect was analysed in the range of 84 to 0.76 Gy/h. For an assessment of biological equivalence in comparison to LDR, HDR irradiations have been performed in the same overall treatment time as the corresponding LDR regimes. RESULTS: Recovery leads to sparing of radiation damage as the dose rate is reduced from 84 to 0.76 Gy/h (20.0 versus 45.7 Gy ED50). No significant additional sparing from 0.9 to 0.76 Gy/h could be demonstrated (44.9 versus 45.7 Gy ED50). Even 30 HDR fractions in 24 h were not sufficient to match the effect of LDR over the same time period (38.2 versus 41.1 Gy ED50). The present data give evidence for a bi-exponential repair process in mouse lip mucosa (T1/2 fast 27 min, T1/2 slow 150 min). Repair is dominated by the faster component (> 80%). CONCLUSIONS: LDR is the most efficient way to deliver radiation if recovery is to be maximised and the overall time kept as short as possible. When used with realistic parameters the LQ model is capable of providing quantitative guidelines in areas of clinical interest.


Assuntos
Mucosa Bucal/efeitos da radiação , Eficiência Biológica Relativa , Animais , Braquiterapia , Feminino , Modelos Lineares , Lábio/efeitos da radiação , Camundongos , Lesões Experimentais por Radiação , Monitoramento de Radiação
17.
Br Dent J ; 181(9): 336-8, 1996 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-8972954

RESUMO

A rare case of candidal infection of the lips is presented. Predisposing factors appeared to be intra-oral candidal carriage, actinic lip damage and Sjögren's syndrome. Systemic antifungal therapy with fluconazole resolved the initial infection and a subsequent recurrence.


Assuntos
Candidíase Bucal/etiologia , Doenças Labiais/etiologia , Adulto , Candidíase Bucal/tratamento farmacológico , Candidíase Bucal/patologia , Feminino , Fluconazol/uso terapêutico , Humanos , Lábio/efeitos da radiação , Doenças Labiais/tratamento farmacológico , Doenças Labiais/patologia , Síndrome de Sjogren/complicações , Luz Solar/efeitos adversos
18.
Med Dosim ; 21(3): 165-7, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8899682

RESUMO

An intra-oral lead shield was developed that consists of a lead base with an aluminum layer that is placed upstream of the lead base. Several such shields with various thicknesses of Al layers were manufactured and quantitatively evaluated in 6 MeV and 12 MeV electron radiation by Thermoluminescent dosimetry (TLD) measurements. The clinical relevance was established by using a 5 cm backscatter block down-stream of the lead shield to simulate anatomical structures of the head and a 0.5 cm superflab bolus upstream of the Al layers of the shield to simulate the patient's lip or cheek. The TLDs were placed between the Al layers of the shield and the superflab to determine the intra-oral skin dose. TLD exposure results revealed that 59.8% of the skin dose at 6 MeV and 45.1% of the skin dose at 12 MeV is due to backscattered electrons. Introduction of a 3.0 mm thick Al layer reduces the backscatter contribution to 13.5% of the back scatter dose at 6 MeV and 56.3% of the back scatter dose at 12 MeV electron radiation.


Assuntos
Alumínio , Chumbo , Boca/efeitos da radiação , Proteção Radiológica/instrumentação , Radioterapia/instrumentação , Espalhamento de Radiação , Bochecha/efeitos da radiação , Elétrons , Desenho de Equipamento , Cabeça/efeitos da radiação , Humanos , Lábio/efeitos da radiação , Doses de Radiação , Dosagem Radioterapêutica , Radioterapia de Alta Energia/instrumentação , Pele/efeitos da radiação , Dosimetria Termoluminescente
19.
Int J Radiat Oncol Biol Phys ; 29(4): 805-11, 1994 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-8040027

RESUMO

PURPOSE: This study was conducted to investigate the action of human recombinant interleukin 1 as a radioprotector for different mouse normal cells other than bone marrow cells. METHODS AND MATERIALS: Semi-continuous injections of tritiated thymidine were administered every 6 h, over 24 h to determine thymidine labeling index. Mice were injected with recombinant human interleukin 1 24 h prior to tritiated thymidine and were compared to control animals that did not receive interleukin 1. Mice were killed 1 h after the last thymidine injection. The 24 h thymidine labeling index for normal tissues and RIF-1 tumor was determined. Labeling indices were also determined 1-14 days after a series of fractionated irradiations with or without pretreatment with a single dose of interleukin 1 administered 24 h prior to the first radiation. RESULTS: The thymidine labeling index of normal tissues was higher following the injection of recombinant human interleukin 1 24 h before radiolabeling. This was found in all normal tissues tested, including the lip and tongue mucosal basal cell layers, crypt cells of the duodenum, alveolar cells of the lung, hepatocytes, and basal skin cells. The thymidine labeling index of RIF-1 fibrosarcoma was not affected by interleukin 1 injection. A single interleukin 1 injection 24 h before the first radiation fraction also increased the thymidine labeling indices of normal tissues after localized fractionated irradiation. The thymidine labeling index of RIF-1 tumor was not increased by interleukin 1 administration except after relatively high radiation doses (20 Gy in five fractions). The ability of interleukin 1 to enhance the thymidine labeling index declined after the first day following the completion of fractionated irradiation. CONCLUSION: Recombinant human interleukin 1 increased the 24 h thymidine labeling index in normal tissues in mice, but not in RIF-1 tumor. Fractionated irradiation could maintain the effect of a single dose of interleukin 1, administered 24 h prior to the first fraction, up to 24 h after the end of radiation.


Assuntos
Interleucina-1/farmacologia , Protetores contra Radiação/farmacologia , Sarcoma Experimental/metabolismo , Timidina/metabolismo , Animais , Relação Dose-Resposta à Radiação , Duodeno/efeitos dos fármacos , Duodeno/metabolismo , Duodeno/efeitos da radiação , Epitélio/efeitos dos fármacos , Epitélio/metabolismo , Epitélio/efeitos da radiação , Feminino , Lábio/efeitos dos fármacos , Lábio/metabolismo , Lábio/efeitos da radiação , Camundongos , Camundongos Endogâmicos C3H , Mucosa Bucal/efeitos dos fármacos , Mucosa Bucal/metabolismo , Mucosa Bucal/efeitos da radiação , Alvéolos Pulmonares/efeitos dos fármacos , Alvéolos Pulmonares/metabolismo , Alvéolos Pulmonares/efeitos da radiação , Dosagem Radioterapêutica , Proteínas Recombinantes/farmacologia , Sarcoma Experimental/radioterapia , Pele/efeitos dos fármacos , Pele/metabolismo , Pele/efeitos da radiação , Fatores de Tempo , Língua/efeitos dos fármacos , Língua/metabolismo , Língua/efeitos da radiação , Trítio
20.
Int J Radiat Oncol Biol Phys ; 29(4): 705-9, 1994 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-7518815

RESUMO

PURPOSE: In Japan, the role of radiotherapy for gingival carcinomas has not been considered as a radical treatment, but only a pre and/or postoperative treatment. This study was aimed to discuss a possibility of radiotherapy for a radical treatment. In this study, radiotherapy was given as an initial treatment for squamous cell carcinomas of the lower gingiva in simultaneous combination with chemotherapy of bleomycin or peplomycin (Tokyo, Japan). METHODS AND MATERIALS: When complete regression of the tumor was obtained, subsequent surgery was postponed with or without a booster of radiotherapy of about 30 Gy until a recurrent lesion was confirmed. RESULTS: Sixty-seven percent of 100 patients with T1 or T2 had complete regression, while only 22 (35.5%) of 62 patients with T3 or T4 had complete regression. The 5-year local control rate by T classification, including the results of secondary treatments (surgery and/or radiotherapy and/or chemotherapy) for recurrent lesions, was 91% for T1, 89% for T2, 76% for T3 and 61% for T4. The 5-year local control rate according to treatment methods was 95% in the group without surgery and 86% in the group with surgery for T1 and T2 patients. The rates were 54% and 71%, respectively for T3 and T4 patients. The cause specific 5-year survival rate by stage was 75% for Stage I, 87% for Stage II, 71% for Stage III, 51% for Stage IV and 70% overall. CONCLUSION: The combination of radiotherapy and chemotherapy could be a conservative radical treatment for T1 and T2 patients with lower gingival carcinoma.


Assuntos
Bleomicina/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Neoplasias Gengivais/tratamento farmacológico , Neoplasias Gengivais/radioterapia , Peplomicina/uso terapêutico , Radioisótopos de Cobalto/uso terapêutico , Terapia Combinada , Seguimentos , Humanos , Lábio/efeitos da radiação , Mucosa Bucal/efeitos da radiação , Estadiamento de Neoplasias , Radioterapia/efeitos adversos
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