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1.
Chimia (Aarau) ; 76(3): 192-202, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38069733

RESUMO

The kinetics of most of chemical energy storage and conversion processes is rate-limited by the mass transport through matter. There is an uncertainty on the corresponding kinetic models, especially if based solely on kinetic theory. Henceforth analytical strategies coupled to setups, in order to capture data for overcoming this limitation are essential. Operando chemical imaging of the kinetics process supports the identification of rate-limiting barriers and definition of actionable kinetic insights. After an overview of the chemical and physical processes in various energy storage/conversion systems, and examples of chemical imaging applied on them, analytical challenges are discussed with particular focus on novel methods and fundamental limitations. Despite convincing success technologies, various scientific challenges of operando chemical kinetics await solution. Apart from technical improvements of the analysis instrumentation, promising developments are seen in advanced digital science.

2.
J Gastrointest Oncol ; 8(5): 842-849, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29184688

RESUMO

BACKGROUND: Studies have shown the negative prognostic impact of increased time between colectomy and postoperative adjuvant chemotherapy (AC) in colon cancer (CC). Our aim was to investigate the role of age and non-organizational factors on access and time to AC. METHODS: All adult patients undergoing surgery for stage II or III CC in the "Région Centre-Val de Loire" in 2013, were selected. Time to AC and socio-demographic factors were collected. Logistic regression modeling was used to identify factors associated with access to AC, and a multivariate analysis performed to identify factors associated with time to AC. RESULTS: Among 404 stage II or III patients who underwent colectomy, 182 (45%; sex ratio 1.5; mean age 67.6 years; range 32-90) received AC. AC patients were younger than those without AC (67.6 vs. 77.9 years) and the difference was even greater for stage III patients (69.0 vs. 82.4). The median time to AC was 48 days, exceeding 42 days in 60% of cases. Living alone, postoperative morbidities, and emergency colectomy were independently associated with increased time to AC. Age and other factors were not associated with delayed AC. CONCLUSIONS: Emergency colectomy, postoperative morbidities, and living alone are associated with increased time to AC. Organizational measures to reduce the time to AC are therefore unlikely to have an impact. In contrast, age is not associated with increased time to AC, but to access to AC. Reasons for omitting AC in older patients requires further study.

4.
JAMA Surg ; 148(7): 624-31, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23552982

RESUMO

IMPORTANCE: Postoperative mortality after junctional and gastric adenocarcinoma resection remains a significant issue. OBJECTIVE: To identify factors predictive of mortality within 30 days of junctional and gastric adenocarcinoma resection in a large national multicenter cohort. DESIGN: A retrospective study collecting data from a multicenter database of patients who underwent resection for junctional and gastric adenocarcinoma from January 1, 1997, through January 31, 2010. A stepwise logistic regression model was built to identify, by multivariate analysis, variables independently predictive of 30-day postoperative mortality (POM). SETTING: Nineteen university teaching hospitals in France. PARTICIPANTS: Two thousand six hundred seventy patients with available data. MAIN OUTCOME MEASURES: The primary end point was POM. Secondary end points included (1) late mortality (30-90 days after resection) and (2) postoperative morbidity. RESULTS: One thousand eight hundred ninety-six patients (71.01%) had gastric adenocarcinoma and 774 (28.99%) had junctional tumors. Neoadjuvant treatment was given to 655 patients (24.53%), and 114 patients (4.27%) died within 30 days of surgery. Postoperative mortality was higher in patients who experienced grades III and IV toxic effects during neoadjuvant treatment compared with those who did not (8.7% vs 2.9%, respectively; P = .007). Multivariate analysis revealed metastatic disease at diagnosis (odds ratio, 9.13 [95% CI, 3.29-25.35]; P < .001) and poor tolerance of neoadjuvant treatment (3.33 [1.25-8.85]; P = .02) as being independently predictive of POM. Centers performing at least 10 resections per year were found to be protective against POM (odds ratio, 0.29 [95% CI, 0.12-0.72]; P = .008). CONCLUSIONS AND RELEVANCE: This large national cohort study confirms that advanced disease heightens the risk of POM; centralization of junctional and gastric adenocarcinoma resection is warranted. The novel finding that grades III to IV toxic effects during neoadjuvant therapy increase POM has significant implications for decision making in this subgroup of patients. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01249859.


Assuntos
Adenocarcinoma/mortalidade , Adenocarcinoma/cirurgia , Junção Esofagogástrica , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/cirurgia , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimiorradioterapia Adjuvante , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Terapia Neoadjuvante , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Estudos Retrospectivos , Fatores de Risco , Neoplasias Gástricas/patologia , Neoplasias Gástricas/terapia
5.
J Oral Maxillofac Surg ; 70(7): 1573-83, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22698292

RESUMO

PURPOSE: This study tested hyperbaric oxygen (HBO) as an adjunct to surgery and antibiotics in the treatment of bisphosphonate-related osteonecrosis of the jaw (ONJ) and evaluated its effects on gingival healing, pain, and quality of life. MATERIALS AND METHODS: The investigators implemented a randomized controlled trial and enrolled a sample composed of patients with ONJ, where the predictor variable was HBO administered at 2 atm twice a day for 40 treatments as an adjunct to conventional therapy of surgery and antibiotics versus conventional therapy alone. Over the next 24 months, oral lesion size and number, pain, and quality of life were assessed. RESULTS: Forty-six patients (mean age, 66 yrs; 57% women) contributed data to the trial. There were no statistically significant differences in the distribution of variables used to assess randomization success between the HBO and standard treatment groups. Seventeen of 25 HBO-treated patients (68%) improved versus 8 of 21 controls (38.1%; P = .043, χ(2) test). Mean time to improvement was 39.7 weeks (95% confidence interval [CI], 22.4 to 57.0 weeks) for HBO-treated patients versus 67.9 weeks (95 CI, 48.4 to 87.5 weeks) for controls (P = .03, log-rank test). However, complete gingival healing occurred in only 14 of 25 HBO-treated patients (52%) versus 7 of 21 controls (33.3%; P = .203, χ(2) test), and time to healing was 59 weeks (95% CI, 42.8% to 75.8%) for HBO-treated patients versus 70 weeks (95 CI, 52.2% to 88.36%) for controls (P = .32, log-rank test). Pain decreased faster for HBO-treated subjects (P < .01, linear regression). Quality-of-life scores for physical health (P = .002) and perceived health (P = .043) decreased at 6 months for control group but for not the HBO group. CONCLUSIONS: ONJ is multifactorial and no single treatment modality is likely to reverse it; however, it is treatable and even advanced presentations can improve with intensive multimodal therapy. Clinically, HBO appears to be a useful adjunct to ONJ treatment, particularly for more severe cases, although this study was underpowered to fully support this claim.


Assuntos
Antibacterianos/uso terapêutico , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/terapia , Desbridamento/métodos , Oxigenoterapia Hiperbárica , Idoso , Alendronato/efeitos adversos , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/tratamento farmacológico , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/cirurgia , Conservadores da Densidade Óssea/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Terapia Combinada , Difosfonatos/efeitos adversos , Feminino , Seguimentos , Gengiva/patologia , Humanos , Imidazóis/efeitos adversos , Masculino , Mieloma Múltiplo/tratamento farmacológico , Osteoporose/tratamento farmacológico , Manejo da Dor , Pamidronato , Estudos Prospectivos , Qualidade de Vida , Resultado do Tratamento , Cicatrização/fisiologia , Ácido Zoledrônico
7.
Int J Radiat Oncol Biol Phys ; 75(3): 717-24, 2009 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19328634

RESUMO

PURPOSE: To elucidate long-term outcomes in 65 consecutive patients meeting a uniform definition of mandibular osteoradionecrosis (ORN) treated with multimodality therapy including hyperbaric oxygen (HBO). METHODS AND MATERIALS: Pretreatment, post-treatment and long-term follow-up of mandibular lesions with exposed bone were ranked by a systematic review of medical records and patient telephone calls. The ranking system was based on lesion diameter and number plus disease progression. Changes from pretreatment to post-treatment and follow-up were analyzed by Wilcoxon signed-rank tests. Improved wound survival, measured by time to relapse, defined as any less favorable rank after HBO treatment, was assessed by Kaplan-Meier analysis. RESULTS: In all, 57 cases (88%) resolved or improved by lesion grade or progression and evolution criteria after HBO (p < 0.001). Four patients healed before surgery after HBO alone. Of 57 patients who experienced improvement, 41 had failed previous nonmultimodality therapy for 3 months and 26 for 6 months or more. A total of 43 patients were eligible for time-to-relapse survival analysis. Healing or improvement lasted a mean duration of 86.1 months (95% confidence interval [95% CI], 64.0-108.2) in nonsmokers (n = 20) vs. 15.8 months (95% CI, 8.4-23.2) in smokers (n = 14) versus 24.2 months (95% CI, 15.2-33.2) in patients with recurrent cancer (n = 9) (p = 0.002 by the log-rank method). CONCLUSIONS: Multimodality therapy using HBO is effective for ORN when less intensive therapies have failed. Although the healing rate in similarly affected patients not treated with HBO is unknown, the improvements seen with peri-operative HBO were durable provided that the patients remained cancer free and abstained from smoking.


Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Oxigenoterapia Hiperbárica , Doenças Mandibulares/terapia , Osteorradionecrose/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Adenoide Cístico/radioterapia , Carcinoma de Células Escamosas/radioterapia , Terapia Combinada/métodos , Intervalos de Confiança , Feminino , Seguimentos , Doença de Hodgkin/radioterapia , Humanos , Masculino , Doenças Mandibulares/cirurgia , Pessoa de Meia-Idade , Osteorradionecrose/cirurgia , Fumar/efeitos adversos , Estatísticas não Paramétricas , Análise de Sobrevida
8.
J Oral Maxillofac Surg ; 65(7): 1321-7, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17577496

RESUMO

PURPOSE: Bisphosphonate (BP)-associated osteonecrosis of the jaw (ONJ) is an emerging problem with few therapeutic options. Our pilot study of BP-ONJ investigated a possible role for hyperbaric oxygen (HBO(2)) therapy. PATIENTS AND METHODS: A total of 16 patients, ranging in age from 43 to 78 years, with BP-ONJ were treated with adjunctive HBO(2) between July 2003 and April 2006. Staging was based on the size and number of oral lesions. Clinical response after treatment and at distant follow-up; the odds of remission, stabilization, or relapse; and time to failure analysis were calculated. RESULTS: The median time on BP therapy before appearance of ONJ symptoms was 18 months, and that from symptom onset to HBO(2) therapy was 12 months. Fourteen of 16 patients (87.5%) improved in stage. The size and number of ONJ lesions were decreased after HBO(2) therapy (P < .001 and P = .008, respectively; Wilcoxon signed-rank test). Immediately after HBO(2) therapy, 7 of 16 patients (44%) were in remission and 8 (50%) had stabilized; however, stabilization without remission was sustained in only 2 patients. At follow-up, 10 of the patients (62.5%) were still in remission or had stabilized. The 7 patients who continued on BP treatment during HBO(2) therapy had a shorter time to failure (8.5 months; 95% confidence interval [CI] = 7.1 to 9.8) than those who discontinued the drug (20.1 months; 95% CI = 17.5 to 23.9; P = .006 by the log-rank test). Clinical response was not associated with cancer type or malignancy remission status. CONCLUSIONS: Adjunctive HBO(2) therapy may benefit patients with BP-ONJ; however, the outcome is improved with cessation of BP administration.


Assuntos
Conservadores da Densidade Óssea/efeitos adversos , Difosfonatos/efeitos adversos , Oxigenoterapia Hiperbárica , Doenças Maxilomandibulares/terapia , Osteonecrose/terapia , Adulto , Idoso , Neoplasias da Mama/tratamento farmacológico , Feminino , Humanos , Doenças Maxilomandibulares/induzido quimicamente , Estimativa de Kaplan-Meier , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/tratamento farmacológico , Osteonecrose/induzido quimicamente , Indução de Remissão
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