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1.
Int J Oral Maxillofac Surg ; 52(12): 1230-1234, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37179134

RESUMO

Oral mucosal melanoma is a rare presentation of malignant melanoma with a 5-year survival rate of only 15%. Oral mucosal melanoma in situ (OMMIS) is its assumed precursor. This report describes one of only 20 documented cases of OMMIS and outlines how early clinical recognition resulted in prompt histopathological diagnosis and subsequent complete surgical excision. A literature review of existing reported cases, their management, and latest outcomes was also performed, highlighting this rare condition for consideration in the differential diagnosis of pigmented oral pathologies.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Melanoma/diagnóstico por imagem , Melanoma/cirurgia , Neoplasias Cutâneas/patologia , Mucosa Bucal/patologia , Diagnóstico Diferencial , Melanoma Maligno Cutâneo
2.
J Laryngol Otol ; 136(12): 1249-1253, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35081997

RESUMO

BACKGROUND: There is currently limited evidence regarding the potential complications of sphenopalatine artery ligation. The post-operative outcomes at two secondary care centres over a 10-year period were reviewed. METHODS: A retrospective review was undertaken of patients undergoing emergency and elective sphenopalatine artery ligation between January 2011 and January 2021. Their demographics, peri-operative care and post-operative outcomes were recorded. The median follow-up time was 54 days (range, 0-2657 days). RESULTS: Ninety-one patients were included. Four patients (4.4 per cent) had a septal perforation at post-operative review. Nineteen patients (20.9 per cent) had post-operative bleeding that extended their in-patient stay, with five patients (5.5 per cent) requiring revision surgery. Pre-operative non-dissolvable nasal packing was used a median of 1 time (range, 0-8 times). CONCLUSION: Further research on outcomes of sphenopalatine artery ligation is needed. Pre-operative non-dissolvable nasal packing, concurrent septal surgical procedures, surgical techniques, and co-morbidities such as hypertension represent potential confounding factors that could not be further assessed in this small, retrospective study.


Assuntos
Artérias , Ligadura , Humanos , Artérias/cirurgia , Epistaxe/epidemiologia , Epistaxe/prevenção & controle , Ligadura/efeitos adversos , Estudos Retrospectivos , Centros de Cuidados de Saúde Secundários , Resultado do Tratamento , Complicações Pós-Operatórias/epidemiologia
3.
J Dig Dis ; 22(7): 399-407, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34048153

RESUMO

OBJECTIVE: Preventing the postoperative recurrence (POR) of Crohn's disease (CD) poses a significant challenge to clinicians. With the advent of biologics, various studies have observed a reduction of recurrence after surgery. Hence, we performed a systematic review and meta-analysis to identify the rate of POR at different time points in the era of biologic use. METHODS: We performed a literature search using Medline and Embase databases for studies investigating biologics in preventing the POR of CD. Data were extracted, and a single-arm meta-analysis with generalized linear mixed model and Clopper-Pearson method for confidence interval (CI) was performed to identify endoscopic, clinical and surgical recurrence rates at 6 months and 1, 2 and 5 years postoperatively. RESULTS: Altogether 24 studies were included in the meta-analysis. The endoscopic, clinical and surgical POR rate with the use of anti-tumor necrosis factor (TNF)-α agents at 1 year was 21.72% (95% CI 16.28%-28.37%), 13.06% (95% CI 8.18%-18.92%) and 3.76% (95% CI 1.37%-9.91%), respectively. The 5-year recurrence rate was 84.21% (95% CI 72.35%-91.57%) and 17.49% (95% CI 9.17%-30.80%) for endoscopic and surgical recurrence, respectively. Subgroup analyses at 1 year for the type of anti-TNF-α agent or the timing of initiation after surgery showed no significant difference in endoscopic, clinical and surgical recurrence rates. CONCLUSIONS: Anti-TNF-α agents are effective at preventing clinical, endoscopic and surgical POR of CD. The timing of initiating biological therapy after surgery has no significant effect on the rate of POR. The efficacy of infliximab and adalimumab for postoperative recurrence prevention is similar.


Assuntos
Terapia Biológica/métodos , Doença de Crohn , Adalimumab/uso terapêutico , Doença de Crohn/tratamento farmacológico , Doença de Crohn/cirurgia , Humanos , Infliximab/uso terapêutico , Recidiva , Prevenção Secundária , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Fator de Necrose Tumoral alfa/antagonistas & inibidores
4.
Eur J Cancer Prev ; 30(5): 373-374, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-33470691

RESUMO

INTRODUCTION: The evolution of colorectal screening has made headway with continual efforts globally to increase screening rates for colonoscopy-naïve patients. However, little has been done to encourage repeat colonoscopies after the initial scope despite recommendations to repeat colonoscopy every 10 years, with the uptake rates of repeat colonoscopy remaining abysmal at 22%. METHODS: Previously, a qualitative systematic review evaluated the barriers and facilitators patients faced in their decisions to undergo colonoscopy, analyzing articles from Medline, Embase, CINAHL, PsycINFO and Web of Science. Key findings from articles which highlighted factors influencing patients' decisions to return for repeat colonoscopies were summarized. RESULTS: Three articles were identified in the search. Facilitators for repeat colonoscopy included patients' assurance garnered from fostered trust in the patient-provider relationship, their intrinsic motivations from fear of cancer and an innate appreciation for the significance of obtaining repeated colonoscopies. Procedural factors such as the option for procedural visualization, its comprehensiveness and the utilization of anesthesia were also crucial motivators. Barriers that patients highlighted comprised of cumbersome bowel preparation and potential complications. DISCUSSION: Recently, minimal research has been conducted on the sentiments of healthcare providers and patients regarding repeat colonoscopy. The lack of emphasis from healthcare institutions on encouraging patients to repeat colonoscopy after 10 years prevents effective colorectal cancer screening. To proficiently alleviate the burden of colorectal cancer, patient counseling has to shift beyond explaining colonoscopy risks and complications to promoting regular follow-up scopes. This article thus calls for more studies to focus on evaluating the uptake of repeat colonoscopies.


Assuntos
Colonoscopia , Neoplasias Colorretais , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/prevenção & controle , Detecção Precoce de Câncer , Humanos
5.
Br J Oral Maxillofac Surg ; 58(10): 1229-1234, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32718749

RESUMO

Oral and Maxillofacial Surgery (OMFS) is one of 10 surgical specialties recognised by the General Medical Council (GMC). The GMC states that newly qualified doctors should be familiar with a wide range of specialties and should refer patients appropriately. However, inadequate awareness of and exposure to OMFS in UK medical schools have been widely reported. Two independent investigators conducted a scoping review of all published articles that have evaluated the preparation of students in OMFS in UK undergraduate medical curricula. Our inclusion criteria were UK studies, articles published since inception, OMFS education, and relevance for undergraduate medical students. Data were extracted in accordance with recommendations by the National Health Service (NHS) Centre for Reviews and Dissemination. These were then analysed by qualitative synthesis. Our initial search yielded a total of 351 articles. Following application of the exclusion criteria according to PRISMA guidelines, 11 articles were included in the final analysis. Four main themes were identified: exposure to OMFS in the medical school curriculum, knowledge of OMFS conditions, knowledge of OMFS career progression, and ability to refer OMFS conditions appropriately. A consistent finding was that most medical students felt that they had insufficient exposure to and awareness of the specialty. All the papers recommended the need for change in the existing undergraduate medical curriculum. This review shows an overwhelming need for further development of OMFS in undergraduate medical curricula in the UK. However, there is insufficient primary research to show how best to achieve this. We propose that future research should focus on improvements in the quality of the current teaching methods and the adoption of new innovations to inspire and educate future doctors.


Assuntos
Educação de Graduação em Medicina , Estudantes de Medicina , Cirurgia Bucal , Currículo , Humanos , Medicina Estatal , Reino Unido
6.
Heredity (Edinb) ; 116(2): 190-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26419336

RESUMO

Whole-genome duplication (WGD) results in new genomic resources that can be exploited by evolution for rewiring genetic regulatory networks in organisms. In metazoans, WGD occurred before the last common ancestor of vertebrates, and has been postulated as a major evolutionary force that contributed to their speciation and diversification of morphological structures. Here, we have sequenced genomes from three of the four extant species of horseshoe crabs-Carcinoscorpius rotundicauda, Limulus polyphemus and Tachypleus tridentatus. Phylogenetic and sequence analyses of their Hox and other homeobox genes, which encode crucial transcription factors and have been used as indicators of WGD in animals, strongly suggests that WGD happened before the last common ancestor of these marine chelicerates >135 million years ago. Signatures of subfunctionalisation of paralogues of Hox genes are revealed in the appendages of two species of horseshoe crabs. Further, residual homeobox pseudogenes are observed in the three lineages. The existence of WGD in the horseshoe crabs, noted for relative morphological stasis over geological time, suggests that genomic diversity need not always be reflected phenotypically, in contrast to the suggested situation in vertebrates. This study provides evidence of ancient WGD in the ecdysozoan lineage, and reveals new opportunities for studying genomic and regulatory evolution after WGD in the Metazoa.


Assuntos
Duplicação Gênica , Genoma , Caranguejos Ferradura/genética , Filogenia , Sequência de Aminoácidos , Animais , Evolução Biológica , Genes Homeobox , Dados de Sequência Molecular , Análise de Sequência de DNA
11.
J Pediatr Surg ; 42(7): 1255-8, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17618890

RESUMO

PURPOSE: Recently, gas amniodistension has been advocated for fetoscopic surgery to employ ergonomics similar to laparoscopy. However, neither the optimal type of gas nor its physiological influence on the fetus have been clearly outlined yet. This study investigates the impact of helium (HE) vs nitrous oxide (N2O) on fetal goats during fetoscopy. METHODS: We insufflated either HE or N2O in 12 pregnant goats (15 fetuses; HE = 7, N2O = 8), then increased the pressures from 0, 4, 7, to 10 mm Hg in 30-minute intervals and recorded the fetal and maternal vital parameters. Finally, whole-body computed tomography to asses for intracorporeal gas was performed. RESULTS: All fetuses survived. Mean fetal vital signs showed no significant differences between HE or N2O at specific pressure levels. In detail, HE/N2O at 0 vs 10 mm Hg caused a fetal temperature decrease (32.9 degrees C/33.2 degrees C vs 32 degrees C/32.5 degrees C), heart rate increase in the N2O group (100/102 vs 102/121 beats per minute), and no significant change in arterial pressure (45.8/48.3 vs 53.7/46.7 mm Hg). The PO2 was adequate (3.7/3.3 vs 3.7/2.9 kPa), whereas the pH remained unchanged (7.4/7.3 vs 7.3/7.3). However, fetal pCO2 was elevated in the N2O group before insufflation (5.5/7.2 vs 6.8/8.0 kPa) owing to maternal hypoventilation (maternal PCO2: 4.9/5.8 vs 5.0/5.4 kPa), correction of which was slower in the fetus than in the maternal animal. Computed tomography ruled out intracorporeal gas accumulation. CONCLUSION: Neither HE nor N2O impose significant physiological harm for the fetus. Heating of the gas and maternal anesthesia seem essential. Considering the potential teratogenicity of N2O, however, HE could be the favorable environment for fetoscopic procedures under gas amniodistension.


Assuntos
Âmnio/fisiologia , Fetoscopia , Hélio , Insuflação/métodos , Óxido Nitroso , Animais , Feminino , Cabras , Concentração de Íons de Hidrogênio , Gravidez , Distribuição Aleatória , Fatores de Risco
12.
Br J Ophthalmol ; 90(1): 99-102, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16361677

RESUMO

AIM: To investigate the effects of indocyanine green (ICG) with or without illumination on rat retinal ganglion cells (RGC) and retinal morphology. METHODS: Intravitreal injections of 1.0 mg/ml ICG solution were performed in rat eyes with or without subsequent illumination for 5 minutes. Eyes in the control group had intravitreal injections of balanced salt solution with illumination. Retrograde labelling of RGC with 6% Fluoro-Gold was performed 1 month later and RGC densities were compared between the three groups. Light microscopy with measurements of outer nuclear layer (ONL) and inner nuclear layer (INL) thicknesses were also performed and compared. RESULTS: Eyes with ICG without illumination showed insignificant reduction in RGC density compared with the control group (p = 0.28), whereas a significant decrease in RGC density was found in eyes that had ICG injection with illumination (p = 0.036). A significant increase in ONL thickness was also observed in the ICG with illumination treated eyes compared with the ICG without illumination and the control groups (p<0.001). No significant difference in INL thickness was observed between the three groups. CONCLUSIONS: Intravitreal injection of 0.1 mg/ml ICG in rat eyes followed by illumination resulted in photosensitising toxicity to RGC. Lower ICG concentration or illumination level should be considered when performing ICG assisted macular surgery.


Assuntos
Verde de Indocianina/toxicidade , Células Ganglionares da Retina/efeitos dos fármacos , Animais , Contagem de Células , Corantes/toxicidade , Feminino , Injeções , Estimulação Luminosa , Fármacos Fotossensibilizantes/toxicidade , Ratos , Retina/efeitos dos fármacos , Retina/patologia , Células Ganglionares da Retina/patologia , Corpo Vítreo
13.
Gen Dent ; 52(2): 162-4; quiz 165, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15101312

RESUMO

Various differential diagnoses pertaining to angina bullosa haemorrhagica (ABH) have been reported in the dental literature; these differential diagnoses include mucous membrane pemphigoid, bullous pemphigoid, bullous lichen planus, epidermolysis bullosa, dermatitis herpetiformis, linear IgA disease, and oral amyloidosis. ABH is characterized by a solitary blood blister in the palate and may worsen progressively, leading to multiple lesions in other areas. The bullae usually rupture spontaneously and the sites heal uneventfully. Possible etiological factors include trauma, long-term use of steroids, diabetes, and hereditary predilection. Pathological studies have yielded nonspecific findings and the underlying etiopathology remains ill-defined. This article describes a case of ABH following the use of a 0.12% chlorhexidine gluconate mouthrinse and presents a concise review of the literature pertaining to ABH and differential diagnoses.


Assuntos
Vesícula/patologia , Clorexidina/análogos & derivados , Doenças da Gengiva/patologia , Hemorragia Gengival/patologia , Anti-Infecciosos Locais/efeitos adversos , Clorexidina/efeitos adversos , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Antissépticos Bucais/efeitos adversos , Palato/patologia
14.
Int Dent J ; 54(1): 42-6, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15005472

RESUMO

OBJECTIVE: To compare the survival of glass ionomer cement (GIC) restorations placed in a dental clinic setting using both the atraumatic restorative treatment (ART) approach with hand instruments, and conventional cavity preparation with rotary instruments. METHOD AND MATERIALS: Two encapsulated high-strength conventional GICs (Fuji IX GP, Ketac-Molar Aplicap) were placed in 82 Class I and 53 Class II preparations and one encapsulated non-gamma 2 amalgam alloy (GK-amalgam) was placed in 32 Class I preparations, in the primary molars of 60 Chinese children with a mean age of 7.40 +/- 1.24 (SD) years. Thus, 9 treatment groups were formed. RESULTS: After two years, there were no significant survival differences found among 7 of the 9 treatment groups (p = 0.99). However, two groups comprising Fuji IX GP and Ketac-Molar Aplicap placed in Class II cavities prepared using the ART approach showed significantly lower restoration survivals (p < 0.001). Only 3 of the 72 initially sealed fissures adjacent to the restorations appeared to retain any GIC material. CONCLUSIONS: In a clinic setting, both the ART hand instrument and conventional rotary instrument methods were equally suitable for high Class I restoration survival, but not for Class II restoration survival where the conventional cavity preparation method was preferable.


Assuntos
Preparo da Cavidade Dentária/instrumentação , Preparo da Cavidade Dentária/métodos , Falha de Restauração Dentária , Restauração Dentária Permanente/métodos , Cimentos de Ionômeros de Vidro , Criança , Amálgama Dentário , Humanos , Procedimentos Cirúrgicos Minimamente Invasivos , Análise de Sobrevida , Dente Decíduo , Resultado do Tratamento
15.
Hong Kong Med J ; 10(1): 49-51, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14967856

RESUMO

Langerhans' cell histiocytosis of the lung can be part of a multisystem disorder or an isolated disorder. Ninety percent of adult patients with Langerhans' cell histiocytosis of the lung are smokers. This article reports a case of Langerhans' cell histiocytosis presenting with haemoptysis. The diagnostic signs on chest X-ray, high-resolution computed tomography, and histology are highlighted, followed by a short review of the literature.


Assuntos
Hemoptise/etiologia , Histiocitose de Células de Langerhans/diagnóstico , Adulto , Humanos , Masculino , Fumar/efeitos adversos
16.
Anaesthesia ; 58(1): 64-8, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12523327

RESUMO

We conducted a randomised controlled study to evaluate whether watching video compact discs intra-operatively using a liquid crystal display (LCD) unit decreased anxiety. Forty-four patients undergoing elective surgery under regional anaesthesia were assigned to either the LCD or control group. Anxiety was measured using the Chinese version of the State-Trait Anxiety Inventory (STAI) and visual analogue score (VAS). The mean (SD) anxiety trait scores were 46.15 (6.28) and 46.40 (7.32) in the control and LCD groups, respectively. The state anxiety of the LCD group [35.50 (7.96)] measured immediately postoperatively was significantly lower than the control group [41.50 (9.02); p = 0.03]. The median (range) reduction in VAS anxiety score was not significantly greater in the LCD group [20 (20 to 80) mm] compared with the control group [12.5 (70 to 60) mm]. Watching video intra-operatively reduces patient anxiety as measured by the STAI.


Assuntos
Anestesia por Condução , Ansiedade/prevenção & controle , Cuidados Intraoperatórios/métodos , Complicações Intraoperatórias/prevenção & controle , Gravação de Videodisco , Adolescente , Adulto , Idoso , Ansiedade/etiologia , Procedimentos Cirúrgicos Eletivos/psicologia , Feminino , Humanos , Complicações Intraoperatórias/psicologia , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Escalas de Graduação Psiquiátrica , Fatores de Risco
17.
J Hand Surg Br ; 27(1): 42-6, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11895344

RESUMO

This prospective study assessed the outcome of percutaneous cannulated screw fixation in 49 of 60 acute scaphoid fractures. The union rate was 100% (mean time for radiological union at 12 weeks). There were no early or mid-term complications and all achieved an excellent functional recovery.


Assuntos
Parafusos Ósseos , Fixação Interna de Fraturas/métodos , Fraturas Ósseas/cirurgia , Osso Escafoide/lesões , Traumatismos do Punho/cirurgia , Adolescente , Adulto , Feminino , Fraturas Ósseas/diagnóstico por imagem , Humanos , Masculino , Estudos Prospectivos , Radiografia , Osso Escafoide/diagnóstico por imagem , Resultado do Tratamento , Traumatismos do Punho/diagnóstico por imagem
18.
Chest ; 120(4): 1212-7, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11591563

RESUMO

BACKGROUND: Although acute left main coronary artery (LMCA) occlusion is a rare clinical entity, it carries a very high mortality rate. The purposes of this study were to evaluate the effect of primary angioplasty for a severely obstructed or totally occluded LMCA, and to determine the incidence, clinical features, outcome, and prognostic determinants in this clinical setting. MATERIALS AND METHODS: Between May 1993 and July 2000, a total of 740 patients with acute myocardial infarction underwent primary angioplasty in our hospital. Eighteen of 740 patients (2.4%) with a severely obstructed or totally occluded LMCA constituted the population of this study. RESULTS: Seventeen of 18 patients (94.4%) experienced pulmonary edema (including 14 patients in cardiogenic shock). Six patients (33.3%) sustained sudden death due to malignant ventricular tachyarrhythmias. Coronary angiography showed that there were variable grade flow of intercoronary collaterals in 12 patients (66.7%), a totally occluded LMCA in 8 patients (44.4%), an incompletely occluded LMCA in 10 patients (55.6%), and a dominant right coronary artery (RCA) in 16 patients (88.9%). Primary angioplasty of the LMCA was performed with a 72.2% procedural success rate. Four patients (22.2%) received coronary artery bypass surgery after angioplasty. Six patients (33.3%) died in the hospital. Two patients died after discharge. Ten of 18 patients (55.6%) survived in long-term follow-up (mean +/- SD, 44 +/- 14 months). Those patients who survived to be discharged had significantly higher combined coexisting incidence of intercoronary collaterals, dominant RCA, and incompletely occluded LMCA (100% vs 0.0%, p = 0.0006) than those patients who died in the hospital. CONCLUSIONS: Acute obstructive LMCA disease generally presented as pulmonary edema, cardiogenic shock, or sudden death. Only those who had combined coexistence of intercoronary collaterals, a dominant RCA, and an incompletely occluded LMCA could survive to be discharged. Our experience suggests that primary LMCA angioplasty is a feasible and effective procedure, and it may save lives in this clinical setting.


Assuntos
Angioplastia Coronária com Balão , Estenose Coronária/terapia , Infarto do Miocárdio/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Coronária , Ponte de Artéria Coronária , Circulação Coronária/fisiologia , Estenose Coronária/mortalidade , Estenose Coronária/fisiopatologia , Morte Súbita Cardíaca/etiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/mortalidade , Infarto do Miocárdio/fisiopatologia , Fatores de Risco , Taxa de Sobrevida , Resultado do Tratamento
19.
Laryngoscope ; 111(6): 982-8, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11404608

RESUMO

OBJECTIVES: Cyclin D1 is a cell cycle regulatory factor that modulates a critical step in cell cycle control. Cyclin D1 is overexpressed in a significant proportion of head and neck cancers and correlates with a poor prognosis. Abrogation of cyclin D1 action through antisense cyclin D1 shows promise as an antitumor therapy, with an inhibitory effect in head and neck squamous cell carcinoma both in vitro and in vivo. The suppressive effect of antisense cyclin D1 in head and neck cancer xenografts in nude mice is incomplete, however, suggesting that combination with another antitumor agent is necessary for complete tumor eradication. Cisplatin is a widely used chemotherapeutic agent in head and neck cancer, and is particularly effective in combination with radiation therapy. In this study, we investigate whether antisense cyclin D1 enhances the sensitivity of head and neck cancer cells to cisplatin. Such an enhancement of sensitivity would suggest that combination therapy using antisense cyclin D1 and cisplatin would be an effective treatment modality for head and neck cancer. STUDY DESIGN: Antisense cyclin D1 was transfected into the head and neck squamous cell carcinoma cell line CCL23 using a plasmid vector. Both the parental CCL23 cells and the antisense cyclin D1-transfected CCL23 cells (CCL23AS) were treated with cisplatin at increasing concentrations. The dosage of cisplatin ranged from 1 microg/mL to 10 microg/mL. Initial exposure to cisplatin was for 2 hours, with increasing exposure times in succeeding experiments. Cell viability assays were done following cisplatin exposure. Dose response curves for the two cell lines were plotted and compared. Western blot analyses were done on the cisplatin-treated cell lines to determine levels of cyclin D1 expression. RESULTS: Increasing concentrations of cisplatin resulted in significantly higher rates of cell killing in the antisense cyclin D1-transfected cells than in the parental cells. The ID50 values for the parental CCL23 cells and the antisense cyclin D1-transfected CCL23 cells were 7 microg/mL and 3 microg/mL, respectively, indicating significant enhancement of sensitivity to cisplatin in the antisense cyclin D1-transfected cells. Western blot analyses demonstrated decreased expression of cyclin D1 in the CCL23AS cells with increasing doses of cisplatin, compared with the parental CCL23 cells. CONCLUSIONS: Antisense cyclin D1-transfected CCL23 cells demonstrate an enhanced sensitivity to the effects of cisplatin compared with the parental cell line. Although the mechanism for this phenomenon is not completely understood, the data suggests the potential use of combination therapy using antisense cyclin D1 and cisplatin for head and neck cancers. While neither agent alone can completely eradicate head and neck cancers, the synergistic effect of the two may be an effective therapeutic protocol for refractory head and neck cancers. Future investigation into the combination of antisense cyclin D1 with cisplatin for treatment of head and neck cancer is needed.


Assuntos
Carcinoma de Células Escamosas/patologia , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Ciclina D1/antagonistas & inibidores , Neoplasias Laríngeas/patologia , RNA Antissenso/farmacologia , Neoplasias da Língua/patologia , Células Tumorais Cultivadas/efeitos dos fármacos , Carcinoma de Células Escamosas/genética , Sobrevivência Celular/genética , Ciclina D1/genética , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias Laríngeas/genética , Neoplasias da Língua/genética , Transfecção
20.
Neuroreport ; 12(3): 541-5, 2001 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-11234760

RESUMO

Following ventral root avulsion in neonatal animals, the degeneration of spinal motoneurons occurs by an apoptotic-like morphological pathway. In adult animals, however, the mechanism of degeneration of injured motoneurons is still controversial. Because caspases are important mediators of apoptosis, we have investigated the effects of the caspase inhibitors, benzyloxycarbonyl-Asp(OMe)fluoromethylketone (Boc-D-FMK), and N-acetyl-Asp-Glu-Val-Asp aldehyde (Ac-DEVD-CHO) on the survival of neonatal and adult spinal motoneurons after root avulsion of the C7 spinal cord. In the control neonatal animals, virtually all motoneurons had degenerated by 7 days following root avulsion. Treatment with either 0.5 microg Boc-D-FMK or 1 microg Ac-DEVD-CHO enhanced the survival of motoneurons to 80% and 85% for up to 2 weeks post-injury. By 21 days post-injury, 70% of avulsed motoneurons were still present after Boc-D-FMK treatment, whereas all avulsed motoneurons died after treatment with Ac-DEVD-CHO. In adult animals, neither inhibitor was neuroprotective for motoneurons following root avulsion. In summary, the inhibition of caspases effectively rescued avulsed neonatal motoneurons which are died by apoptotic pathway. By contrast, because caspase inhibitors failed to rescue injured motoneurons in adult animals, their death may occur by a non-apoptotic pathway.


Assuntos
Inibidores de Caspase , Neurônios Motores/citologia , Neurônios Motores/enzimologia , Raízes Nervosas Espinhais/lesões , Fatores Etários , Clorometilcetonas de Aminoácidos/farmacologia , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Axotomia , Sobrevivência Celular/efeitos dos fármacos , Inibidores de Cisteína Proteinase/farmacologia , Relação Dose-Resposta a Droga , Feminino , Oligopeptídeos/farmacologia , Ratos , Ratos Sprague-Dawley , Raízes Nervosas Espinhais/citologia , Raízes Nervosas Espinhais/fisiologia
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