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The popular textbook and literature model I(λx,λm) = K(λx,λm)(1-10-Ax) or its variants for correlating the sample absorption and fluorescence often fails even for the simplest samples where the fluorophore is the only light absorber. Reported is a first-principle model I(λx,λm) = K(λx,λm)Ax,f10-(Ax,sdx+Am,sdm) for correlating the sample fluorescence measured with a conventional spectrofluorometer and its UV-vis absorbance quantified with a conventional UV-vis spectrophotometer. This model can be simplified or expanded for a variety of fluorescence analyses. First, it enables curve-fitting fluorescence intensity as a function of the fluorophore or sample absorbance over a sample concentration range impossible with existing models. Second, it provides the theoretical foundation for an inner-filter-effect (IFE)-correction method developed earlier and explains mathematically the linearity between the IFE-corrected fluorescence and the fluorophore concentration or absorbance. Third, this model can be expanded for quantitative mechanistic studies of fluorescence intensity variations triggered by stimuli treatments. One demonstrated example is to quantify temperature effects on the emission-wavelength-specific and total fluorescence quantum yield of anthracene. We expect that this first-principle model will be broadly adopted for both student education that promotes evidence-based learning and a variety of fluorescence applications where disentangling sample absorption and emission are critical for reliable data analysis.
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Corantes Fluorescentes , Humanos , Espectrometria de Fluorescência/métodosRESUMO
BACKGROUND: In head and neck cancer (HNC), 3-month post-treatment positron emission tomography (PET)/computed tomography (CT) reliably identifies persistent/recurrent disease. However, further PET/CT surveillance has unclear benefit. The impact of post-treatment PET/CT surveillance on outcomes is assessed at 12 and 24 months. METHODS: A 10-year retrospective analysis of HNC patients was carried out with long-term serial imaging. Imaging at 3 months included either PET/CT or magnetic resonance imaging, with all subsequent imaging comprised of PET/CT. PET/CT scans at 12 and 24 months were evaluated only if preceding interval scans were negative. Of 1114 identified patients, 284 had 3-month scans, 175 had 3- and 12-month scans, and 77 had 3-, 12-, and 24-month scans. RESULTS: PET/CT detection rates in clinically occult patients were 9% (15 of 175) at 12 months, and 4% (3 of 77) at 24 months. No difference in outcomes was identified between PET/CT-detected and clinically detected recurrences, with similar 3-year disease-free survival (41% vs 46%, P = .91) and 3-year overall survival (60% vs 54%, P = .70) rates. Compared with 3-month PET/CT, 12-month PET/CT demonstrated fewer equivocal reads (26% vs 10%, P < .001). Of scans deemed equivocal, 6% (5 of 89) were ultimately found to be positive. CONCLUSIONS: HNC patients with negative 3-month imaging appear to derive limited benefit from subsequent PET/CT surveillance. No survival differences were observed between PET/CT-detected and clinically detected recurrences, although larger prospective studies are needed for further investigation.
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Imagem Multimodal , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/diagnóstico , Feminino , Neoplasias de Cabeça e Pescoço/diagnóstico , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Fatores de Tempo , Adulto JovemRESUMO
Determination of the true surface areas, concentrations, and particle sizes of gold nanoparticles (AuNPs) is a challenging issue due to the nanoparticle morphological irregularity, surface roughness, and size distributions. A ligand adsorption-based technique for determining AuNP surface areas in solution is reported. Using a water-soluble, stable, and highly UV-vis active organothiol, 2-mercaptobenzimidazole (MBI), as the probe ligand, we demonstrated that the amount of ligand adsorbed is proportional to the AuNP surface area. The equivalent spherical AuNP sizes and concentrations were determined by combining the MBI adsorption measurement with Au(3+) quantification of aqua regia-digested AuNPs. The experimental results from the MBI adsorption method for a series of commercial colloidal AuNPs with nominal diameters of 10, 30, 50, and 90 nm were compared with those determined using dynamic light scattering, transmission electron microscopy, and localized surface plasmonic resonance methods. The ligand adsorption-based technique is highly reproducible and simple to implement. It only requires a UV-vis spectrophotometer for characterization of in-house-prepared AuNPs.
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Coloide de Ouro/química , Ligantes , Nanopartículas Metálicas/química , Adsorção , Benzimidazóis/química , Ouro/química , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Transmissão/métodos , Modelos Estatísticos , Nanopartículas/química , Tamanho da Partícula , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta/métodos , Compostos de Sulfidrila/química , Ressonância de Plasmônio de Superfície , Propriedades de SuperfícieRESUMO
AIMS: A general protocol was derived for optimizing the production of pure, high concentration Clostridium endospore suspensions. METHODS AND RESULTS: Two sporulation methods were developed that yielded high concentrations of notably pure Clostridium sporogenes, C. hungatei and C. GSA-1 (Greenland ice core isolate) spore suspensions (10 ml of 10(9) spores ml(-1) with >99% purity each). Each method was derived by evaluating combinations of three sporulation conditions, including freeze drying of inocula, heat shock treatment of cultures, and subsequent incubation at suboptimal temperatures that yielded the highest percentage of sporulation. Pure spore suspensions were characterized in terms of dipicolinic acid content, culturability, decimal reduction time (D) value for heat inactivation (100 degrees C) and hydrophobicity. CONCLUSIONS: While some Clostridium species produce a high percentage of spores with heat shock treatment and suboptimal temperature incubation, other species require the additional step of freeze drying the inocula to achieve a high percentage of sporulation. SIGNIFICANCE AND IMPACT OF THE STUDY: Pure Clostridium spore suspensions are required for investigating species of medical and environmental importance. Defining the conditions for optimal spore production also provides insight into the underlying mechanisms of Clostridium sporulation.
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Clostridium/crescimento & desenvolvimento , Esporos Bacterianos/crescimento & desenvolvimento , Clostridium/fisiologia , Liofilização , Temperatura Alta , Interações Hidrofóbicas e Hidrofílicas , Viabilidade Microbiana , Ácidos Picolínicos/análise , Esporos Bacterianos/química , Esporos Bacterianos/fisiologia , TemperaturaRESUMO
PURPOSE: To determine long-term outcomes in patients receiving stereotactic radiotherapy (SRT) as a boost after external beam radiotherapy (EBRT) for locally advanced nasopharyngeal carcinoma (NPC). METHODS AND MATERIALS: Eight-two patients received an SRT boost after EBRT between September 1992 and July 2006. Nine patients had T1, 30 had T2, 12 had T3, and 31 had T4 tumors. Sixteen patients had Stage II, 19 had Stage III, and 47 had Stage IV disease. Patients received 66 Gy of EBRT followed by a single-fraction SRT boost of 7-15 Gy, delivered 2-6 weeks after EBRT. Seventy patients also received cisplatin-based chemotherapy delivered concurrently with and adjuvant to radiotherapy. RESULTS: At a median follow-up of 40.7 months (range, 6.5-144.2 months) for living patients, there was only 1 local failure in a patient with a T4 tumor. At 5 years, the freedom from local relapse rate was 98%, freedom from nodal relapse 83%, freedom from distant metastasis 68%, freedom from any relapse 67%, and overall survival 69%. Late toxicity included radiation-related retinopathy in 3, carotid aneurysm in 1, and radiographic temporal lobe necrosis in 10 patients, of whom 2 patients were symptomatic with seizures. Of 10 patients with temporal lobe necrosis, 9 had T4 tumors. CONCLUSION: Stereotactic radiotherapy boost after EBRT provides excellent local control for patients with NPC. Improved target delineation and dose homogeneity of radiation delivery for both EBRT and SRT is important to avoid long-term complications. Better systemic therapies for distant control are needed.
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Neoplasias Nasofaríngeas/cirurgia , Radiocirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/radioterapia , Lesões por Radiação/patologia , Radiocirurgia/efeitos adversos , Dosagem Radioterapêutica , Lobo Temporal/efeitos da radiação , Resultado do TratamentoRESUMO
OBJECTIVES: To study the long-term quality of life outcomes of a group of unselected patients for the long-term effects of uvulopalatopharyngoplasty (UPPP). STUDY DESIGN: Retrospective chart review and telephone survey. METHODS: Forty-nine patients who underwent UPPP between July 1980 and July 1983 and who had their medical records were reviewed and were asked to grade on a visual analogue scale (VAS) the clinical benefits and complications of UPPP after the surgery. RESULTS: Forty-three (87.8%) males and six (12.2%) female patients were studied. Improvement in snoring, excessive daytime somnolence, and nocturnal arousals were seen after UPPP with decreased effectiveness after time. The most common complication of UPPP was velopharyngeal insufficiency (VPI) (28.5%); however, dry throat and swallowing difficulty tended to be more severe in those patients who had them. No correlation between the snoring and VPI VAS grades was observed. Forty-three patients had a preoperative sleep study and 22 patients a postoperative sleep study. There was lack of correlation between the significant subjective clinical improvement and their postoperative polysomnography. CONCLUSION: When undertaking UPPP, both subjective and objective benefits should be weighed against the risk of long-term ill effects. Patients should also be warned that the long-term side effects such as VPI, dry throat, and abnormal swallowing sensation might be more common than previously expected.
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Procedimentos Cirúrgicos Otorrinolaringológicos/psicologia , Faringe/cirurgia , Procedimentos de Cirurgia Plástica/psicologia , Qualidade de Vida , Apneia Obstrutiva do Sono/cirurgia , Úvula/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Otorrinolaringológicos/métodos , Palato Mole/cirurgia , Polissonografia , Estudos Retrospectivos , Apneia Obstrutiva do Sono/fisiopatologia , Inquéritos e Questionários , Fatores de Tempo , Resultado do TratamentoRESUMO
OBJECTIVE: To clarify the extent, timing, and patient perspectives of great auricular nerve (GAN) morbidity and recovery after nerve sacrifice during parotidectomy during the first postoperative year. DESIGN: Prospective series. SETTING: Tertiary care academic medical center. Patients Twenty-seven consecutive patients who underwent parotidectomy with GAN sacrifice. MAIN OUTCOME MEASURES: Preoperatively and at 3, 6, 9, and 12 months postoperatively, we performed light touch sensation tests on each patient to develop an ink map representing anesthesia and paresthesia in the GAN sensory territory; patients also completed an outcomes questionnaire. RESULTS: Twenty-two (81%) of 27 patients completed follow-up. The prevalence and average area of anesthesia decreased continually during the first year according to sensory testing and patient scoring. Half of the patients had no anesthesia at 12 months. The prevalence and average area of paresthesia increased during the first year according to sensory testing; however, the contiguity and subjective scoring of paresthesia peaked at 6 months and decreased in subsequent follow-up points. Throughout the first year, patients had difficulty using the telephone, shaving, combing their hair, wearing earrings, and sleeping on the operative side because of both anesthesia and paresthesia. CONCLUSIONS: The impact of GAN sacrifice morbidity on patient quality of life is tolerable and improves during the first postoperative year. However, we feel that GAN morbidity may be bothersome enough to warrant efforts to preserve the posterior branch of the GAN when possible and appropriate.
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Nervos Cranianos/cirurgia , Orelha/inervação , Parestesia/etiologia , Glândula Parótida/inervação , Glândula Parótida/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Prospectivos , Qualidade de Vida , Inquéritos e Questionários , Resultado do TratamentoRESUMO
BACKGROUND: Cyclin D1 and p16 are involved in the regulation of G1 checkpoint and may play an important role in the tumorigenesis of nasopharyngeal carcinoma (NPC). Previous studies have examined the level of expression of cyclin D1 and p16 in primary untreated NPC but no such information is available for recurrent NPC. We set out in this study to examine the expression level of cyclin D1 and p16 in recurrent NPC that have failed previous treatment with radiation +/- chemotherapy. PATIENTS AND METHODS: A total of 42 patients underwent salvage nasopharyngectomy from 1984 to 2001 for recurrent NPC after treatment failure with radiation +/- chemotherapy. Twenty-seven pathologic specimens were available for immunohistochemical study using antibodies against cyclin D1 and p16. RESULTS: Positive expression of cyclin D1 was observed in 7 of 27 recurrent NPC specimens (26%) while positive p16 expression was seen in only 1 of 27 recurrent NPC (4%). CONCLUSION: While the level of expression of cyclin D1 in recurrent NPC was similar to that of previously untreated head and neck cancer, the level of p16 expression in recurrent NPC samples was much lower than that reported for previously untreated cancer. The finding that almost all (96%) of the recurrent NPC lack expression of p16 suggested that loss of p16 may confer a survival advantage by making cancer cells more resistant to conventional treatment with radiation +/- chemotherapy. Further research is warranted to investigate the clinical use of p16 both as a prognostic marker and as a potential therapeutic target.
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High-risk patients with a growing mass require proper assessment, including a thorough history, physical examination, and fine-needle aspiration for diagnosis.
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OBJECTIVES/HYPOTHESIS: To determine the diagnostic accuracy and the ideal timing of fluoro-fluorodeoxyglucose positron-emission tomography (PET) in the posttreatment surveillance of head and neck mucosal squamous cell carcinoma (HNSCC). STUDY DESIGN: Retrospective chart review. METHODS: Our sample includes 103 adult patients with 118 posttreatment PET scans who had undergone treatment for HNSCC. We correlated PET results with surgical pathology and clinical outcome in the subsequent 6 months. RESULTS: For the detection of locoregional persistent or recurrent HNSCC, PET scans had a sensitivity of 82%, specificity of 92%, positive predictive value (PPV) of 64%, negative predictive value (NPV) of 97%, and overall accuracy of 90%. For the detection of distant metastases, PET scans had a sensitivity of 89%, specificity of 97%, PPV of 85%, NPV of 98%, and overall accuracy of 96%. PET scans of the head and neck region performed greater than 1 month after the completion of radiation compared with scans performed within 1 month had a significantly higher sensitivity of 95% versus 55% (P < .01) and NPV of 99% versus 90% (P < .01). CONCLUSION: PET is effective in detecting distant metastases in the posttreatment surveillance for HNSCC patients. A negative PET is highly reliable for all sites. However, a positive PET in the head and neck region is unreliable because of a high false-positivity rate. PET of the head and neck region has a statistically significant risk of a false-negative reading when performed within 1 month of radiation.
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Carcinoma de Células Escamosas/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/secundário , Carcinoma de Células Escamosas/cirurgia , Feminino , Fluordesoxiglucose F18 , Seguimentos , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Recidiva Local de Neoplasia/diagnóstico por imagem , Neoplasia Residual , Valor Preditivo dos Testes , Compostos Radiofarmacêuticos , Radioterapia Adjuvante , Estudos Retrospectivos , Sensibilidade e Especificidade , Fatores de Tempo , Resultado do TratamentoRESUMO
OBJECTIVES: To develop an animal model to investigate the survival of split-thickness skin grafts (STSGs) on bone without periosteum, to compare STSG attachment to bone with and without periosteum, and to determine the effect of fibrin glue on STSG attachment to bone. DESIGN: Prospective laboratory study. SETTING: University laboratory. SUBJECTS: Sprague-Dawley rats. MAIN OUTCOME MEASURE: Percentage of survival of the STSGs at 2 weeks determined independently by the authors and a third, blinded head and neck surgeon. RESULTS: In experiment 1, which included 40 rats, the sutured STSGs showed an average survival rate of 38% when attached to bone with periosteum, 6% when attached to bare bone, and 10% when attached to bare bone using fibrin glue. The poor survival rate was thought to be attributable to the animals scratching at their bolster dressings. In experiment 2, 18 animals underwent a posteriorly based U-shaped flap of skin and subcutaneous tissue. The grafts were placed and isolated from the overlying flap with a biosynthetic wound dressing. The sutured STSG survival rates were as follows: 87% when attached to bone with periosteum, 94% when attached to bare bone, and 74% when attached to bare bone using fibrin glue. CONCLUSIONS: The survival of STSGs attached to bare bone was comparable to that of STSGs attached to bone with periosteum when grafts were protected with the skin-subcutaneous flap. The STSGs that were fixed with 0.1 cc of fibrin glue demonstrated poorer survival rates than those attached with sutures and were associated with more seromas.
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Transplante de Pele , Animais , Osso e Ossos , Adesivo Tecidual de Fibrina/uso terapêutico , Sobrevivência de Enxerto , Masculino , Modelos Animais , Periósteo , Estudos Prospectivos , Ratos , Ratos Sprague-Dawley , SeromaRESUMO
Studies of protein and organothiol interactions with silver nanoparticles (AgNPs) are important for understanding AgNP nanotoxicity, antimicrobial activity, and material fabrications. Reported herein is a systematic investigation of the effects of both reduced and oxidized protein cysteine residues on protein interactions with AgNPs. The model proteins included wild-type and mutated protein GB3 variants that contain 0, 1, or 2 reduced cysteine residues, respectively. Bovine serum albumin (BSA) that contains a total of 34 oxidized (disulfide-linked) cysteine residues and one reduced cysteine residue was also included. Protein cysteine content has no detectable effect on the kinetics of protein/AgNP binding. However, only proteins that contain reduced cysteine residues induce significant AgNP dissolution. Proteins can slow down, but do not prevent the AgNP dissolution induced by subsequently added organothiols. The insights provided in this work are important to the mechanistic understanding of AgNP stability in biofluids that are rich in proteins and amino acid thiols.
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PURPOSE: To assess long-term efficacy and toxicity associated with external beam irradiation (EBRT) and interstitial (192)Ir implantation for the treatment of squamous carcinoma of the base of tongue. METHODS AND MATERIALS: Between April 1975 and December 1993, 41 patients with base-of-tongue carcinomas were treated with (192)Ir interstitial implants after EBRT at Stanford University. One patient had Stage I, 6 had Stage II, 7 had Stage III, and 27 had Stage IV tumors. Twenty-eight patients had cervical lymph node involvement at diagnosis. All received EBRT to a median dose of 50 Gy (range 48.9-68 Gy) to the primary tumor and regional lymph nodes before brachytherapy. Interstitial implant was performed 2-4 weeks after EBRT. Intraoperatively, nylon catheters were placed via steel trocars into the base of tongue, glossotonsillar groove, and pharyngo-epiglottic fold using a catheter looping technique. Twenty-three of 28 node-positive patients also underwent simultaneous neck dissections. Postoperatively, the (192)Ir seeds were inserted and allowed to remain in place for approximately 35 h to achieve a median tumor dose of 26 Gy (range 20-34 Gy) to a median volume of 73 cc. Survival, local control, and complications were assessed. RESULTS: With a median follow-up of 62 months (range 9-215) for all patients and 90 months for alive patients, the 5-year Kaplan-Meier survival estimate was 66%. The 5-year local control rate was 82%, with 7 patients recurring locally, 2 of whom were salvaged with surgery. Nodal control was achieved in 93% of patients with either EBRT alone or in combination with neck dissection. The 5-year freedom from distant metastasis rate was 83%. Acute complications included transient bleeding (5%) and infection (8%). Late complication included soft-tissue necrosis/ulceration (7%), osteoradionecrosis (5%), and xerostomia. CONCLUSION: Base-of-tongue carcinoma can be effectively treated with EBRT and (192)Ir implant boost. Local control is excellent and complication rates are acceptable.
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Carcinoma de Células Escamosas/radioterapia , Radioisótopos de Irídio/uso terapêutico , Neoplasias da Língua/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Braquiterapia/métodos , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Radioterapia/métodos , Análise de Sobrevida , Neoplasias da Língua/patologia , Falha de TratamentoRESUMO
PURPOSE: Treatment of nasopharyngeal carcinoma using conventional external beam radiotherapy (EBRT) alone is associated with a significant risk of local recurrence. Stereotactic radiosurgery (STR) was used to boost the tumor site after EBRT to improve local control. METHODS AND MATERIALS: Forty-five nasopharyngeal carcinoma patients received a STR boost after EBRT at Stanford University. Seven had T1, 16 had T2, 4 had T3, and 18 had T4 tumors (1997 American Joint Commission on Cancer staging). Ten had Stage II, 8 had Stage III, and 27 had Stage IV neoplasms. Most patients received 66 Gy of EBRT delivered at 2 Gy/fraction. Thirty-six received concurrent cisplatin-based chemotherapy. STR was delivered to the primary site 4-6 weeks after EBRT in one fraction of 7-15 Gy. RESULTS: At a medium follow-up of 31 months, no local failures had occurred. The 3-year local control rate was 100%, the freedom from distant metastasis rate was 69%, the progression-free survival rate was 71%, and the overall survival rate was 75%. Univariate and multivariate analyses revealed N stage (favoring N0-N1, p = 0.02, hazard ratio HR 4.2) and World Health Organization histologic type (favoring type III, p = 0.002, HR 13) as significant factors for freedom from distant metastasis. World Health Organization histologic type (p = 0.004, HR 10.5) and age (p = 0.01, HR 1.07/y) were significant factors for survival. Late toxicity included transient cranial nerve weakness in 4, radiation-related retinopathy in 1, and asymptomatic temporal lobe necrosis in 3 patients who originally had intracranial tumor extension. CONCLUSION: STR boost after EBRT provided excellent local control in nasopharyngeal carcinoma patients. The incidence of late toxicity was acceptable. More effective systemic treatment is needed to achieve improved survival.
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Neoplasias Nasofaríngeas/radioterapia , Neoplasias Nasofaríngeas/cirurgia , Radiocirurgia/métodos , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Combinada , Fracionamento da Dose de Radiação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/tratamento farmacológico , Prognóstico , Radiocirurgia/efeitos adversos , Radioterapia/efeitos adversosRESUMO
Two hundred consecutive patients underwent myocardial revascularization for left main coronary artery disease between January, 1975, and December, 1981. The mean age of this group was 64 +/- 8 years, and 78.5% of the patients were men. The anginal pattern was chronic stable in 6% of the patients and progressive or unstable in the remainder. Resting electrocardiograms showed prior myocardial infarction in 45.5%. Left ventricular end-diastolic pressure was elevated in 145 patients, and ejection fraction was less than 50% in 40 patients. The mean number of bypass grafts per patient was 3.2 +/- 1.4 (standard deviation). Seventeen patients underwent major concomitant cardiovascular procedures. The operative mortality was 3.5%, and the incidence of perioperative infarction was 3%. Factors associated with reduced operative survival were increased age; unstable angina, or acute myocardial infarction, or both; female sex; circumflex-dominant circulation; and major concomitant procedures. Late mortality at a mean follow-up of 33.5 months was 6%, and 91% of the surviving patients assessed their quality of life as "excellent" or "good."
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Ponte de Artéria Coronária , Doença das Coronárias/cirurgia , Adulto , Idoso , Doença das Coronárias/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade , Complicações Pós-OperatóriasRESUMO
This study was conducted to evaluate the effect of sperm separation methods of semen samples collected from bulls subjected to scrotal insulation on embryonic development after in vitro fertilization (IVF) and to determine whether IVF results would be affected by various heparin concentrations. Morphologically abnormal semen samples were obtained and cryopreserved from Holstein bulls following scrotal insulation for 48 hours. Standard protocols using the Percoll gradient (90%/45%) method and the swim-up method were used to separate spermatozoa fractions in experiment I. The pellet (A(p)) and the 45% layer (B(p)) were isolated from the Percoll separation, while for the swim-up separation, the supernatant (A(s)) and the interphase (B(s)) were isolated. The overall blastocyst rate for our laboratory control semen was 23.1 +/- 2.1% for Percoll separations (A(p) and B(p)) and 18.2 +/- 2.0% for swim-up (A(s) and B(s)) separations. This rate was higher (P <.01) than the rate observed for the semen from the bull that had the greatest response to scrotal insult 5 days prior to the insult, when it was 9.2 +/- 2.1% for the Percoll separation and 20.7 +/- 2.3% for the swim-up separation, while semen from 27 days after scrotal insulation (D +27) resulted in no blastocyst formation for the Percoll separation and a 4.2 +/- 2.1% rate for the swim-up separation. In experiment II, semen was sampled from the bulls that responded in the greatest and least degrees to scrotal insult 5 days before scrotal insulation (D -5) and on days 23 (D +23) and 34 (D +34) after scrotal insulation. These samples were exposed to IVF mediums with 3 different heparin concentrations (0.1, 1.0, and 10 microg/mL). There was a significant difference (P <.05) in developmental scores between the D -5 (1.08 +/- 0.08), D +23 (0.9 +/- 0.08), and D +34 (0.8 +/- 0.08) samples, but no differences were observed in blastocyst formation based on the number of cleaved embryos. Increasing the heparin concentration resulted in higher (P <.01) embryonic developmental scores. In conclusion, when semen samples with high percentages of abnormal spermatozoa are used for IVF, semen separation preparation methods affect results. Our results show that the separation methods used under these conditions were inadequate in their ability to provide potentially competent sperm for IVF. However, selecting appropriate sperm separation procedures could improve in the IVF embryonic development of semen from bulls used in artificial insemination. Also, an increase in the heparin concentration was able to partially overcome deficiencies, which suggests that morphologically abnormal spermatozoa undergo capacitation despite possible structural changes to the plasma membrane.
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Desenvolvimento Embrionário/fisiologia , Espermatozoides/citologia , Espermatozoides/fisiologia , Animais , Bovinos , Feminino , Fertilização in vitro/veterinária , Masculino , Gravidez , Preservação do SêmenRESUMO
OBJECTIVES/HYPOTHESIS: The objective was to compare and contrast the functional and cosmetic outcomes of patients who underwent total parotidectomy with and without reconstruction using an inferiorly based sternocleidomastoid muscle flap. STUDY DESIGN: Retrospective review in the setting of a university medical center. METHODS: Twenty-four patients underwent a total parotidectomy. Fifteen patients had reconstruction with an inferiorly based sternocleidomastoid muscle flap, and nine patients had no reconstruction. Clinical examination was performed independently by two head and neck surgeons and one aesthetician to evaluate cosmetic outcome, presence of gustatory flushing or sweating, and return of facial nerve and greater auricular nerve function. RESULTS: With the mean follow-up of 22 months, the group having reconstruction showed a better cosmetic outcome compared with the group without reconstruction. Objective testing for Frey syndrome demonstrated gustatory sweating in 20% of the group having reconstruction group versus 22% in the group without reconstruction. There was no difference in length of operation, hospital stay, or facial nerve function. Objective testing of facial sensation revealed that only 40% in the group having reconstruction had normal sensation to light touch compared with 78% in the group without reconstruction. CONCLUSION: The inferiorly based sternocleidomastoid muscle flap offers improved cosmetic results in patients undergoing total parotidectomy. However, there is a decreased return of greater auricular nerve function, probably attributable to relocation of the nerve stump anteriorly. Benefit was not seen in prevention of Frey syndrome measured objectively; however, the group having reconstruction had fewer clinical symptoms of gustatory sweating or flushing.
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Glândula Parótida/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Técnicas Cosméticas , Feminino , Humanos , Masculino , Complicações Pós-Operatórias , Retalhos Cirúrgicos , Sudorese Gustativa/etiologia , Resultado do TratamentoRESUMO
OBJECTIVE: To determine whether the administration of perioperative corticosteroids is effective in ameliorating facial nerve paresis after parotidectomy. STUDY DESIGN: Prospective, randomized, double-blinded, placebo-controlled clinical trial at a university medical center. METHODS: Patients scheduled for parotidectomy and who met inclusion criteria were invited to enroll in the protocol. They were stratified according to the anticipated surgery (superficial or total parotidectomy) and then received one of two doses of dexamethasone (0.51 or 1.41 mg/kg divided into three doses) or placebo solution immediately preoperatively and then every 8 hours for 16 hours postoperatively. The facial nerve was graded for proportion (percentage) of function at each of the four major regions (frontal, orbital, midface and upper lip, and lower lip). The early postoperative function and rate of return of function were compared among the treatment groups. RESULTS: Forty-nine patients were enrolled and evaluated (18 in the control group, 16 receiving low-dose dexamethasone, and 15 receiving high-dose dexamethasone). No therapeutic advantage of dexamethasone treatment could be appreciated with respect to the degree of early postoperative nerve function (81.3% for control patients vs. 69.5% for dexamethasone-treated patients [ =.239]). Similarly, the median time to recovery of complete facial nerve function was 60 days in the control group and was 150 days in the dexamethasone-treated patients. CONCLUSIONS: Dexamethasone administration in patients undergoing parotidectomy is not justified. Despite the relatively modest risk profile of dexamethasone, we were unable to demonstrate any benefit in patients who were treated with either low-dose or high-dose steroids compared with placebo-treated patients in a randomized, controlled trial.
Assuntos
Dexametasona/uso terapêutico , Paralisia Facial/tratamento farmacológico , Paralisia Facial/etiologia , Glucocorticoides/uso terapêutico , Doenças Parotídeas/cirurgia , Adulto , Método Duplo-Cego , Paralisia Facial/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estatísticas não ParamétricasRESUMO
OBJECTIVES/HYPOTHESIS: There is a paucity of data to guide the optimal management of the airway in patients after maxillectomy. The decision on whether a concomitant tracheostomy is needed is often dictated by the surgeon's training and experience. We reviewed our experience with maxillectomy to assess the need for tracheostomy in postoperative airway management. STUDY DESIGN: Retrospective analysis at a university hospital. METHODS: We identified 121 patients who underwent 130 maxillectomies between October 1990 and September 2001. Twenty-four of these were total (all six walls removed), 45 were subtotal (two or more walls removed), and 61 were limited (only one wall removed). Reconstruction ranged from none to microvascular free flap, with split-thickness skin graft being the most common reconstructive option. RESULTS: Only 10 tracheostomies (7.7%) were performed at the time of maxillectomy. These included four tracheostomies in patients who underwent bulky flap reconstruction, two tracheostomies in patients who underwent both flap reconstruction and mandibulectomy, one tracheostomy in a patient who underwent mandibulectomy, one tracheostomy in a patient with mucormycosis in anticipation of prolonged ventilatory support postoperatively, and two tracheostomies at the surgeons' discretion because of concern for upper airway edema. Among the 111 patients who underwent 120 maxillectomies without concomitant tracheostomy, 1 patient (0.9%), a 74 year-old man with oxygen-dependent chronic obstructive pulmonary disease, required repeat intubation on day 3 and again on day 10 after the surgery, because of respiratory failure; fiberoptic examination confirmed the absence of upper airway compromise. CONCLUSIONS: The routine performance of tracheostomy in patients undergoing maxillectomy is unnecessary. Selective use of tracheostomy may be indicated in situations in which mandibulectomy or bulky flap reconstruction is performed or a concern for postoperative oropharyngeal airway obstruction because of edema or packing exists.
Assuntos
Obstrução das Vias Respiratórias/cirurgia , Maxila/cirurgia , Seio Maxilar/cirurgia , Neoplasias Otorrinolaringológicas/cirurgia , Doenças dos Seios Paranasais/cirurgia , Neoplasias dos Seios Paranasais/cirurgia , Cuidados Pós-Operatórios , Complicações Pós-Operatórias/cirurgia , Traqueostomia , Procedimentos Desnecessários , Adulto , Idoso , Idoso de 80 Anos ou mais , Obstrução das Vias Respiratórias/diagnóstico , Terapia Combinada , Feminino , Humanos , Masculino , Mandíbula/cirurgia , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Reoperação , Estudos RetrospectivosRESUMO
OBJECTIVE: To review the 2- to 17-year outcome of nasopharyngectomy following local recurrence of nasopharyngeal carcinoma. DESIGN: Retrospective review. SETTING: University medical center. PATIENTS: Thirty-seven patients with biopsy-proven recurrent nasopharyngeal cancer followed up for a minimum of 2 years after transpalatal, transmaxillary, and/or transcervical resection with and without neck dissection. OUTCOME: Clinical examination, magnetic resonance imaging, chest x-ray examination, and liver function tests to determine re-recurrence; unlimited follow-up. RESULTS: With a mean follow-up of 5.4 years, the crude, 5-year, overall, free-of-disease survival rate was 52%, local control at 5 years was 67%, and the 5-year actuarial survival rate was 60%. Survival by recurrent T stage (rT) was as follows: rT1, 73%; rT2, 40%; rT3, 14%; and rT4, 0%. Complications occurred in 54% and included 1 death from carotid artery injury and 1 patient with permanent pharyngeal plexus paralysis with resultant dysphagia. The remaining patients had transitory complications that spontaneously resolved, required further surgery (closure of palate fistula, debridement, and reapplication of skin graft), or required further medical therapy. CONCLUSIONS: The results of this study are better than most published reports of additional irradiation for rT1 and rT2 lesions. More recent radiation studies that use radiosurgery or implants suggest promising early results. A randomized prospective study comparing surgery with additional irradiation for recurrent disease at the primary site is warranted.