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1.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(3): 520-526, 2021 Mar 10.
Artigo em Chinês | MEDLINE | ID: mdl-34814423

RESUMO

Objective: To study the association between apparent temperature (AT) and the incidence of hand,foot, and mouth disease (HFMD) and its spatial heterogeneity in 46 cities in Guangdong, Anhui and Jilin provinces, and provide scientific evidence for the early warning of HFMD. Methods: The data of HFMD incidence and meteorological factors from 2009 to 2018 in Guangdong province, 2009 to 2015 in Anhui province, and 2013 to 2018 in Jilin province were collected. Distributed lag non-linear models were constructed to investigate the association between AT and the incidence of HFMD in 46 cities from three provinces in China. Meta-analysis was used to pool the city-specific estimates, and Meta-regression was applied to analyze the factors that may cause spatial heterogeneity. Results: The relationship between daily AT and the incidence of HFMD in 46 cities appeared nonlinear. The association in Guangdong was similar to that in Jilin, and the risk of HFMD increased with the increase of AT. While the risk of HFMD in Anhui first increased with the increase of AT, and peaked at 18.1 ℃ and then went down. AT on different levels showed different lag impacts and the higher AT showed greater and longer lag impact. The spatial heterogeneity of associations may have been caused by latitude, longitude, average temperature, and average sunshine hours. Conclusions: AT is a comprehensive index to evaluate the association between temperature, relative humidity and wind speed and the incidence of HFMD. Higher AT may increase the risk of HFMD. The AT and HFMD relationship across spatial heterogeneity varies depending on geographic location and meteorological conditions.


Assuntos
Doença de Mão, Pé e Boca , Doenças da Boca , China/epidemiologia , Doença de Mão, Pé e Boca/epidemiologia , Humanos , Incidência , Conceitos Meteorológicos , Temperatura
2.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(8): 1445-1452, 2021 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-34814566

RESUMO

Objective: To identify the threshold of a health warning system based on the association of apparent temperature and years of life lost (YLL). Methods: Daily mortality records and meteorological data were collected from 364 Chinese counties for 2006-2017. Distributed lag nonlinear model and multivariate Meta-analyses were applied to estimate the association between the apparent temperature and YLL rate. A regression tree model was employed to estimate the warning thresholds of the apparent temperature. Stratified analyses were further conducted by age and cause of death. Results: The daily YLL rate was 23.6/105. The mean daily apparent temperature was 15.7 ℃. U-shaped nonlinear associations were observed between apparent temperature and YLL rate. The actual temperature-caused YLL rate for the elderly was higher than the young population. The daily excess deaths rate increased with the higher effect levels. Conclusions: Regression tree model was employed to define the warning threshold for meteorological health risk. The present study provides theoretical support for the weather-related health warning system.


Assuntos
Temperatura Baixa , Temperatura Alta , Idoso , China/epidemiologia , Humanos , Dinâmica não Linear , Temperatura , Tempo (Meteorologia)
3.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(10): 1840-1845, 2021 Oct 10.
Artigo em Chinês | MEDLINE | ID: mdl-34814621

RESUMO

Objective: To understand the cognition and related factors on the use of HIV non-occupational post-exposure prophylaxis (nPEP) among men who have sex with men (MSM). Methods: The snowballing method was applied to recruit research subjects who were ≥18 years old, had sex with men in the past three months, and were aware of nPEP in MSM groups in Beijing, Shenzhen, and Kunming from March 15 to April 14, 2019. Data on social demographics, behavioral characteristics, basic knowledge of nPEP, consultation, and using nPEP were collected through "i guardian Platform". The logistic regression model was used to analyze the related factors affecting the use of nPEP. Results: Among 1 809 investigated, 39.8% (720 persons) were aware of the basic knowledge of nPEP, 33.4% (605 persons) had consulted nPEP, and 15.0% (271 persons) had used nPEP. In addition, multivariate logistic regression analysis showed that factors as whether to have sex with men infected with HIV in the last three months (OR=2.58, 95%CI: 1.64-4.07), the frequency of HIV testing in the past year (OR=2.47, 95%CI: 1.28-5.11), nPEP knowledge awareness (OR=0.70, 95%CI: 0.49-0.99), whether to consult nPEP (OR=70.98, 95%CI: 40.51-136.83) were related to the use of nPEP. Conclusions: MSM still have poor cognition of nPEP. It is necessary to strengthen the publicity and education of nPEP in MSM and promote the use of nPEP after HIV exposure as soon as possible.


Assuntos
Infecções por HIV , Minorias Sexuais e de Gênero , Adolescente , Cognição , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Humanos , Masculino , Profilaxia Pós-Exposição
4.
Zhonghua Wei Chang Wai Ke Za Zhi ; 24(11): 1008-1014, 2021 Nov 25.
Artigo em Chinês | MEDLINE | ID: mdl-34823302

RESUMO

Objective: Most patients with asymptomatic colorectal diverticulosis are easily overlooked. However, some of diverticulosis become diverticulitis, bleeding and even perforation, which cause extensive harm to patients. The purpose of this study is to analyze the incidence, clinical features, diagnosis and treatment of colorectal diverticulosis in order to improve the clinical understanding of diverticulosis and its related complications. Methods: A descriptive cohort study was carried out. Clinical data of 554 patients with colorectal diverticulosis confirmed by CT, colonoscopy, digestive tract radiography or operation in Peking University First Hospital from January 2009 to June 2019 were retrospectively analyzed. Patients with malignant tumors, autoimmune diseases, long term use of immunosuppressive drugs, chronic liver diseases and renal diseases, and mental disorders were excluded. The analysis parameters included gender, onset age, clinical symptoms, location of diverticulitis, treatment and prognosis. According to the criteria established by the World Society of Emergency Surgery (WSES), acute diverticulitis was divided into 5 stages based on the extension of the infectious process. Stage 0 was simple diverticulitis and stage 1-4 was complicated diverticulitis. Results: Among the 554 patients with colorectal diverticulosis, 358 (64.6%) were males, the median onset age was 63 years; 191 patients (34.5%) had various digestive symptoms, of whom 113 (20.4%) had chronic constipation and abdominal distension, 78 (14.1%) had chronic diarrhea and abdominal pain; the other 363 patients had no obvious abdominal symptoms. Four hundred and six patients were found by colonoscopy and 465 patients were found by CT. Twenty-five patients were diagnosed by lower gastrointestinal tract radiography and 3 were confirmed during operation. There were 339 patients with multiple diverticula (61.2%) and 215 patients with single diverticulum (38.8%). 76.5% (424/554) of diverticula were located in colon, 37.0% (205/554) in ascending colon, 21.3% (118/554) in multiple sites, and 2.2% (12/554) in rectum. The median diameter of diverticulum was 7 mm, and 78 cases (14.1%) was ≥30 mm. Forty-nine patients (8.8%) developed acute diverticulitis, including 13 patients with simple diverticulitis and 36 patients with complicated diverticulitis. Among 36 patients with complicated diverticulitis, 29 (80.6%) were males, 27 (75.0%) had recurrent abdominal pain and fever before onset; diverticula of 25 cases were located in sigmoid colon; 11 cases in ascending colon. Nine cases developed sigmoid colon perforation and 8 cases developed vesicocolonic fistula, and these 17 patients underwent surgical treatment. The other 19 cases with complicated diverticulitis developed gastrointestinal bleeding, of whom 18 cases were male, 11 cases were located in ascending colon; 13 cases were healed after conservative treatment, 4 cases received endoscopic hemostatic intervention, and 2 cases underwent surgery. Conclusions: Colorectal diverticulosis is more common in male patients, and CT and colonoscopy are main diagnostic methods. The symptoms of complicated colonic diverticulitis are related to the location of diverticulum. In addition to symptomatic treatment, surgical procedures are the most important treatments.

5.
Am J Ophthalmol ; 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34780794

RESUMO

PURPOSE: To determine the feasibility and accuracy of non-mydriatic ultra-widefield (UWF) fundus photographs taken in a hematology clinic setting for screening of sickle cell retinopathy (SCR) DESIGN: Prospective cohort study METHODS: Setting: Single-site study at the Johns Hopkins Sickle Cell Center for Adults and the Wilmer Eye Institute Study Population: Ninety eyes of 46 consecutive adult participants with sickle cell disease (SCD) Observation Procedure: Bilateral non-mydriatic fundus photos taken by clinic personnel during the participants' routine hematology appointment were graded by two masked retina specialists at the Wilmer Eye Institute for the presence of non-proliferative SCR (NPSR) and proliferative sickle retinopathy (PSR). A third retina specialist adjudicated in cases of grader disagreement. All participants underwent the standard dilated fundus exam (DFE) within two years of acquisition of UWF photos. MAIN OUTCOME MEASURE: Sensitivity and specificity of non-mydriatic UWF images for the detection of NPSR and PSR RESULTS: PSR was noted in 19 of 90 eyes that underwent DFE and 9 of 67 gradable UWF images. Inter-rater agreement between the two graders was moderate with κ = 0.65 (0.43-0.87) for PSR. For gradable UWF photos, the sensitivity and specificity of detecting SCR using the non-mydriatic photos compared to the DFE were 85.2% and 62.5% for NPSR, respectively, and 69.2% and 100% for detection of PSR, respectively. One participant required ophthalmic therapy in both eyes for active sea-fan neovascularization. CONCLUSIONS: UWF imaging shows utility in screening for SCR and may help identify patients with PSR who require a DFE and who may benefit from treatment.

6.
Zhonghua Xue Ye Xue Za Zhi ; 42(9): 752-756, 2021 Sep 14.
Artigo em Chinês | MEDLINE | ID: mdl-34753230

RESUMO

Objective: To evaluate the safety and efficacy of vemurafenib in the treatment of BRAF(V600E)-mutated Erdheim-Chester disease (ECD) . Methods: We retrospectively analyzed the clinical data, response rate, adverse events and survival of 12 patients with ECD treated with vemurafenib from March 2015 to October 2020 in Peking Union Medical College Hospital. Results: Of 12 patients [7 males and 5 females, median age = 51.5 (range, 32-66) years old], the median number of organs involved was 6 (range, 4-8) , and the median treatment duration of vemurafenib was 11 (3-60) months. All patients had improvement of clinical symptoms, of which 2 cases were completely relieved, and 10 cases were partially relieved. Seven patients evaluated by (18)F-FDG-positron emission tomography/computed tomography achieved a metabolic response, including 2 patients with a complete metabolic response and 5 patients with a partial metabolic response. The common adverse events in the overall cohort were grade 1 to 2 (Common Terminology Criteria for Adverse Events 5.0) , including skin rash (58.3%) , arthralgia (25.0%) , and digestive tract reactions (16.7%) . The median follow-up time was 13.5 (3-60) months. One patient with central nervous system involvement died due to a cerebrovascular event, and one patient relapsed 10 months after drug withdrawal. The estimated 2-year overall survival rate and 2-year progression free survival rate were 88.89% and 66.67%, respectively. Conclusions: Vemurafenib is safe and effective in the treatment of BRAF(V600E)-mutated ECD.


Assuntos
Doença de Erdheim-Chester , Proteínas Proto-Oncogênicas B-raf , Adulto , Idoso , Doença de Erdheim-Chester/tratamento farmacológico , Doença de Erdheim-Chester/genética , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Estudos Retrospectivos , Vemurafenib
7.
Phys Rev Lett ; 127(17): 172701, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34739292

RESUMO

We report the first (in)elastic scattering measurement of ^{25}Al+p with the capability to select and measure in a broad energy range the proton resonances in ^{26}Si contributing to the ^{22}Mg(α,p) reaction at type I x-ray burst energies. We measured spin-parities of four resonances above the α threshold of ^{26}Si that are found to strongly impact the ^{22}Mg(α,p) rate. The new rate advances a state-of-the-art model to remarkably reproduce light curves of the GS 1826-24 clocked burster with mean deviation <9% and permits us to discover a strong correlation between the He abundance in the accreting envelope of the photospheric radius expansion burster and the dominance of ^{22}Mg(α,p) branch.

8.
Opt Express ; 29(15): 24264-24277, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34614675

RESUMO

Many factors still need to be evaluated to fully understand the physical mechanisms determining optical cavity vibration, which are crucial for designing and constructing a transportable ultra-stable laser. Herein, a detailed dynamic analysis is used to characterize the vibration modes of a transportable optical cavity. The first five resonance modes are identified in the presence of a cavity support, and the guidelines to achieve a high first-order resonance frequency are proposed; thereby, high robustness is described using a 50 mm length optical cavity. The results demonstrate that the first-order resonance of up to 681 Hz with a gross weight of 2.51 kg can be achieved using an optimization strategy for given cavity support. The theoretical results are consistent with simulation and experiment. With the optimal group, a 1.34 Hz linewidth transportable ultra-stable laser at 1550 nm is established, and a linewidth of 1.5 Hz and frequency instability of 9.5×10-15@1s are obtained after the test including 100 km actual road transportation and 34 min continuous vibration. The test condition is equivalent to ∼ 1000 km road transportation. Our method can be readily extended to other transportable optical cavities, providing a powerful tool for improving the robustness of vibration, particularly important for transportable environments.

9.
Zhonghua Yi Xue Za Zhi ; 101(37): 3006-3011, 2021 Oct 12.
Artigo em Chinês | MEDLINE | ID: mdl-34638192

RESUMO

Objective: To investigate the correlation between resilience and cognitive function in patients with schizophrenia. Methods: Fifty-nine patients with first-episode schizophrenia and 86 healthy controls were enrolled. Patients with schizophrenia were enrolled from the psychiatric outpatient and inpatient Department of the Third Affiliated Hospital of Sun Yat-sen University from September 2017 to January 2020, while healthy controls were recruited through advertising. The levels of resilience and cognitive function were compared between the two groups.Meanwhile, the partial correlation analysis of resilience and cognitive function of the two groups was performed. Results: There was no statistically significant difference in gender, marriage and age between the two groups (all P>0.05), and there were 39 males and 20 females with an average age of (23.8±7.4) years in the schizophrenia group, while 47 males and 39 females with an average age of (22.9±4.7) years in the healthy control group. However, there was a significant difference inyears of education between the two groups (P<0.05). The total score of resilience [(56.9±16.7) vs(68.0±14.4)] and scores ofthree factorsin patients with schizophrenia were significantly lower than that in healthy controls(all P<0.05). The total score of MATRICS Consensus Cognitive Battery (MCCB)[(23±12) vs (42±11)] and each subscale score in patients with schizophrenia were significantly lower than that in healthy controls(all P<0.05). Partial correlation analysis showed that the total score of resilience and tenacity were correlated with symbol coding of schizophrenia(partial correlation coefficients were 0.286, 0.289, respectively, both P<0.05). The total score of resilience and the scores of tenacity, strength and optimism were all correlated with emotion management ability of schizophrenia(partial correlation coefficients were 0.334, 0.271, 0.382, 0.308, respectively, all P<0.05). In the healthy controls, the total score of resilience, tenacity and optimism were correlated with symbol coding(partial correlation coefficients were 0.268, 0.225, 0.291, respectively, all P<0.05). Strength and optimism were correlated with Hopkins verbal learning test (HVLT)(partial correlation coefficients were 0.268, 0.225, respectively, both P<0.05). Strength was correlated with spatial span, continuous performance test(partial correlation coefficients were 0.244, 0.217, respectively, bothP<0.05). The total scores of resilience and tenacity, strength and optimism were correlated with emotional management ability(partial correlation coefficients were 0.306, 0.230, 0.286, 0.289, respectively, all P<0.05), while the total scores of resilience, strength and optimism were correlated with the total score of MCCB(partial correlation coefficients were 0.291, 0.359, 0.287, respectively, all P<0.05). Conclusion: The current study suggests that resilience and cognitive function of patients with first-episode schizophrenia areimpaired significantly. Resilience in patients with schizophrenia isrelated to partial neurocognitive function and emotion management ability in social cognitive function.


Assuntos
Transtornos Cognitivos , Esquizofrenia , Adolescente , Adulto , Cognição , Feminino , Humanos , Masculino , Psicologia do Esquizofrênico , Aprendizagem Verbal , Adulto Jovem
10.
Br J Surg ; 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34643677

RESUMO

BACKGROUND: The therapeutic value of repeat hepatic resection (rHR) or radiofrequency ablation (RFA) for recurrent hepatocellular carcinoma (HCC) is unknown. This study aimed to investigate the safety and efficacy of rHR or RFA. METHODS: This was a retrospective multicentre study of patients with recurrent HCC within the Milan criteria who underwent rHR or RFA at nine university hospitals in China and Italy between January 2003 and January 2018. Survival after rHR or RFA was examined in unadjusted analyses and after propensity score matching (1 : 1). RESULTS: Of 847 patients included, 307 and 540 underwent rHR and RFA respectively. Median overall survival was 73.5 and 67.0 months after rHR and RFA respectively (hazard ratio 1.01 (95 per cent c.i. 0.81 to 1.26)). Median recurrence-free survival was longer after rHR versus RFA (23.6 versus 15.2 months; hazard ratio 0.76 (95 per cent c.i. 0.65 to 0.89)). These results were confirmed after propensity score matching. RFA was associated with lower morbidity of grade 3 and above (0.6 versus 6.2 per cent; P < 0.001) and shorter hospital stay (8.0 versus 3.0 days, P < 0.001) than rHR. CONCLUSION: rHR was associated with longer recurrence-free survival but not overall survival compared with RFA.

11.
Zhonghua Yi Shi Za Zhi ; 51(4): 195-200, 2021 Jul 28.
Artigo em Chinês | MEDLINE | ID: mdl-34645115

RESUMO

The Painting Album of Cityscapes and Business was finished in the early Qing Dynasty with realism. This painting album described the prosperity in business and everyday life in Suzhou during the late Ming and the early Qing Dynasties. They were drawn and painted retrospectively, ie, the content of the pictures was based on existing paintings handed down. In the painting album, more than ten medical-related elements were specifically depicted, such as traditional Chinese medicine clinics and pharmacies and seven ophthalmology-related elements including one clinic specialized in ophthalmology, two spectacle shops, two people wearing eyeglasses and three blind people. Up to now, no specialized ophthalmology clinics and spectacle shops have been found in earlier literature and paintings. It can be speculated that the Painting Album of Cityscapes and Business is the earliest album of paintings depicting clinics specialized in ophthalmology and spectacle shops in China. This painting album provides important information for the study of the medical industry in Suzhou in the late Ming and the early Qing Dynasties, particularly, in terms of ophthalmology-related diagnosis and treatment.


Assuntos
Oftalmologia , Pinturas , China , Comércio , Humanos , Medicina Tradicional Chinesa , Estudos Retrospectivos
12.
Zhonghua Jie He He Hu Xi Za Zhi ; 44(8): 705-710, 2021 Aug 12.
Artigo em Chinês | MEDLINE | ID: mdl-34645136

RESUMO

Objective: To summarize the clinical characteristics and species distribution of nontuberculous mycobacteria(NTM). Methods: We conducted a retrospectively chart review of 453 adult patients with 532 positive cultures with NTM diagnosed and treated in Peking Union Medical College Hospital from January 2014 to December 2018. The information including clinical findings, imaging and etiological data were obtained from clinical examination system. Among these 453 patients, 75 cases met the diagnostic criteria for NTM, with detailed clinical data, culture results and radiological images. Of these patients, 38 were males and 37 were females, with an average age of (50.8±16.2) years. Clinical manifestations, imaging features, NTM species and treatment were analyzed. Results: Among 75 NTM patients, 43 cases (57.3%, 43/75) were infected with Mycobacterium avium Complex (MAC)/intracellular, 18 cases (24.0%, 18/75) with Mycobacterium turtle/abscess, and 7 cases (9.3%, 7/75) with Mycobacterium kansasii. Comorbidities existed in 64.0% patients (48/75). The top two common comorbidities were previous tuberculosis (25.3%, 19/75) infection and clinical bronchiectasis (18.7%, 14/75). After the respiratory disease (82.7%, 62/75), we identified bloodstream as the most frequent manifestation of NTM infection (25.3%, 19/75). MAC was often associated with infection in respiratory system and bloodstream, while rapidly growing mycobacteria (RGM) was more commonly detected in lymph nodes and skin and soft tissues. Cough/expectoration (77.4%, 48/62) was the most common clinical symptom of NTM disease, followed by fever and dyspnea. The frequent imaging findings were nodules (41.9%, 26/62), bronchiectasis (37.1%, 23/62), and fibrous cavities (24.2%, 15/62). In disseminated NTM disease, 94.7% (18/19) patients had underlying diseases and 89.5% (17/19) patients had long-term immunosuppression. Conclusion: The most common NTM species was Mycobacterium avium/intracellular in our series. The predominant infected organ was the respiratory system. Previous tuberculosis history likely increased the risk of infection.


Assuntos
Infecções por Mycobacterium não Tuberculosas , Micobactérias não Tuberculosas , Adulto , Feminino , Hospitais Gerais , Humanos , Masculino , Infecções por Mycobacterium não Tuberculosas/diagnóstico por imagem , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Complexo Mycobacterium avium , Estudos Retrospectivos
13.
Zhonghua Wei Chang Wai Ke Za Zhi ; 24(10): 889-896, 2021 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-34674464

RESUMO

Objective: The surgical indications, resection extent and management principle of lateral lymph node dissection (LLND) in lower rectal cancer have been controversial between Eastern and Western countries. This study aims to provide a theoretical basis for the rational implementation of LLND by reviewing the changes of LLND strategy over the past 30 years in a single-center, and analyzing prognostic factors for the survival outcomes of patients with lateral lymph node metastasis (LLNM). Methods: A retrospective observational study was performed. Clinical data of 289 patients with rectal cancer who received LLND at the Department of General Surgery of Peking University First Hospital from 1990 to 2019 were collected. Patients were divided into three groups based on decades. There were 89 cases in 1990-1999 group, 92 cases in the 2000-2009 group, and 108 cases in the 2010-2019 group. Data analyzed: (1) patient baseline data; (2) surgery and postoperative recovery; (3) lateral lymph node dissection; (4) postoperative survival and prognosis of patients with positive lateral lymph nodes. The surgical methods and pathological results of LLND were compared between groups, and the prognostic risk factors of patients with LLNM were analyzed. Results: A total of 289 patients underwent radical resection with LLND' accounting for 6.3% of the 4542 patients with rectal cancer during the same period in our hospital. Except decade-by-decade increase in tumors with distance from anal verge ≤ 7 cm, the proportion of ulcerated tumors, and the proportion of neoadjuvant radiochemotherapy, the differences in other baseline data were not statistically significant among 3 decade groups (all P>0.05). The proportion of LLND in the 3 groups decreased decade by decade [9.9% (89/898) vs. 8.0% (92/1154) vs. 4.3% (108/2490), χ(2)=40.159, P<0.001]. The proportion of laparoscopic surgery and unilateral LLND increased, while the mean operative time, intraoperative blood loss, surgical complications above grade III and postoperative hospital stay decreased decade by decade. These 289 patients completed a total of 483 lateral dissections, including 95 cases of the unilateral dissection and 194 cases of the bilateral dissection. The proportion of LLND in the 3 groups decreased decade by decade [9.9% (89/898) vs. 8.0% (92/1154) vs. 4.3% (108/2510), P<0.001]. The median number of dissected lymph nodes in the internal iliac artery and obturator regions increased (2 vs. 3 vs. 3, P<0.001), but those in the common iliac and external iliac regions decreased significantly (4 vs. 3 vs. 2, P=0.014). A total of 71 patients with LLNM were identified. The rate of LLNM in the 2010-2019 group was significantly higher than that in the previous two groups [37.0% (40/108) vs. 16.9% (15/89) vs. 17.4% (16/92), P=0.001]. The patients with LLNM showed a poorer overall survival (OS) and disease-free survival (DFS) compared with negative lateral lymph nodes (P<0.001). There were statistically significant differences in 5-year OS rate (30.9% vs. 27.2% vs. 0, P=0.028) and 5-year DFS rate (28.3% vs. 16.0% vs. 0, P=0.038) among patients with only internal iliac lymph node metastasis, patients with only obturator lymph node metastasis, and patients with external iliac or common iliac lymph node metastasis. Multivariate analysis of prognostic factors showed that external iliac or common iliac lymph node metastasis was an independent risk factor for OS (HR=1.649, 95%CI: 1.087-2.501) and DFS (HR=1.714, 95%CI: 1.173-2.504) in patients with LLNM (all P<0.05) . The OS and DFS were not significant different in patients with LLNM among 3 decade groups. Conclusions: In the past decade, the proportion of LLND in rectal cancer has decreased significantly. However, LLNM rate has been significantly increased due to preoperative imaging assessments focusing on suspicious LLNM without compromising the survival. Internal iliac artery and obturator lymph nodes can be regarded as regional lymph nodes with a satisfactory prognosis after LLND. For suspected external iliac or common iliac lymph node metastasis, the significance of LLND remains to be further evaluated.


Assuntos
Excisão de Linfonodo , Neoplasias Retais , Dissecação , Humanos , Linfonodos , Prognóstico , Neoplasias Retais/cirurgia , Resultado do Tratamento
14.
Int J Radiat Oncol Biol Phys ; 111(3S): e201-e202, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34700902

RESUMO

PURPOSE/OBJECTIVE(S): In the UK START and Canadian hypofractionated whole breast radiotherapy (RT) trials, few patients were Black, received prior chemotherapy, or had large breast size, all factors associated with RT-induced breast toxicity. The purpose of this prospective trial was to assess the safety and efficacy of delivering 15 fractions of hypofractionated simultaneous integrated boost (SIB) RT to patients under-represented on trials of hypofractionated breast RT and who have characteristics which increase their risk for local recurrence and cutaneous toxicity from breast RT. MATERIALS/METHODS: We conducted a prospective, single-arm pilot study to evaluate a once daily 15 fraction SIB RT regimen of 39.9 Gy in 2.66 Gy fractions to the breast/chest wall with or without regional nodal irradiation (RNI) and SIB of 8.1 Gy in 0.54 Gy fractions. Women with Stage 0-IIIB breast cancer who had one or more of the following characteristics were approached for enrollment: 1) prior chemotherapy for breast cancer; 2) > 25 cm breast/chest wall separation; 3) non-White race; 4) ≤ 50 years old; or 5) requiring RNI. Primary endpoint was Grade 3 cutaneous toxicity rate by CTCAE v.5. Among patients who received RNI (n = 30), rates of Grade 3 brachial plexopathy by RTOG criteria and 20% or greater increase in arm lymphedema, were additional primary endpoints. Patients were assessed prior to RT, last day of RT, and 3 weeks, 9 weeks and 1 year post RT. Local regional recurrence free survival (LRFS) was a secondary endpoint. RESULTS: Among 74 participants, 57% received prior chemotherapy, 19% had breast/chest wall separation > 25cm, 39% were Black, 36% were ≤ 50 years old, and 41% were prescribed RNI. Median body mass index was 30.0 (range 17.3 - 54.9). Ten patients received post mastectomy RT. One patient developed Grade 3 radiation dermatitis 3 weeks post RT. No other Grade 3 or higher cutaneous toxicities were observed up to 1 year post RT. One patient developed a grade 3 axillary infection 3 weeks post RT, which resolved after intravenous antibiotics. No patients who received RNI developed grade 3 brachial plexopathy or a 20% increase in the ipsilateral arm volume during the study period. With a median follow up of 60 months (range 12-113 months), one in-breast recurrence with simultaneous distant metastases occurred. Two additional patients developed distant metastases alone. The 5-year LRFS and overall survival rates were 98.6% and 98.5%, respectively. CONCLUSION: Our results indicate that SIB radiation therapy is well-tolerated with acceptable cutaneous toxicity rates up to 1 year post RT even among patients who are at high risk for RT-induced breast side effects. The high rates of local control and overall survival following SIB treatment are promising and support condensed courses of RT in patients who would typically receive a sequential boost due to higher risk for local recurrence.

15.
Int J Radiat Oncol Biol Phys ; 111(3S): e290-e291, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34701106

RESUMO

PURPOSE/OBJECTIVE(S): During prostate high-dose-rate (HDR) brachytherapy, physicians select needle positions in a peripheral loading technique based on experience but without knowledge of the achievable dose distribution. Sub-optimal needle placement may lead to unfavorable dose distributions even after plan optimization. We propose a new deep learning-based method to predict HDR needle position for prostate HDR brachytherapy. MATERIALS/METHODS: The proposed framework consists of three major steps: (1) deformable registration via registration network (Reg-Net), (2) multi-atlas ranking and (3) needle regression. To model the global spatial relationship among multiple organs, binary masks of the target and organs at risk are transformed into distance maps which describe the distance of each local voxel to the organ surfaces. Reg-Net is utilized to deformably register the distance maps from multi-atlas set to match a patient's distance map and then bring needle maps from multi-atlas to this patient via spatial transformation. Several criteria are used for multi-atlas ranking including prostate volume similarity, multi-organ semantic image similarity and needle position criteria. Finally, needle regression is used to refine the final needle positions. A retrospective study of consecutively treated patients was used to evaluate the feasibility of the proposed method. We performed a five-fold cross validation to evaluate the proposed method. We generated a new dose plan for each patient based on predicted needle location. Target and organ dose volume histogram (DVH) metrics were used to quantify the difference between the clinical and predicted needle plans. All plans were normalized to prostate V100 of 95%. RESULTS: Ninety predicted needle plans were compared to clinical plans. In each case, the needle prediction algorithm completed within 1 minute. See table for comparison of target and organ DVH metrics (mean and standard deviation). Predicted needle plans had slightly greater target dose heterogeneity. The RTOG constraints of bladder V75% < 1 cc, rectum V75% < 1cc, and urethra V125% < 1 cc were met in all predicted plans. CONCLUSION: It is feasible to use this novel deep-learning-based method to predict needle locations for HDR prostate brachytherapy a priori. This strategy merits further study to improve utilization and quality of prostate brachytherapy.

16.
Int J Radiat Oncol Biol Phys ; 111(3S): e297, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34701120

RESUMO

PURPOSE/OBJECTIVE(S): We proposed a novel tool of dose-linear-energy-transfer (LET) volume histogram (DLVH) and performed an exploratory study to investigate rectal bleeding in prostate cancer treated by intensity-modulated proton therapy (IMPT). MATERIALS/METHODS: DLVH was constructed with dose and LET as two axes, while the normalized volume of the structure was contoured in the dose-LET plane as iso-volume lines. We defined DLVH index, DLv% (d,l), i.e., v% of the structure have a dose of d ≥ Gy and an LET of l ≥ keV/µm similar to dose-volume histogram index Dv%. Nine prostate cancer patients with rectal bleeding (CTCAE grade ≥2) were included as the adverse event group, while 48 patients with no complication were considered as the control group. P-value map was constructed by comparison of the DLVH indices of all patients between the two groups using the Mann-Whitney U test. Dose-LET volume constraints (DLVCs) were derived based on the P-value map with a manual selection procedure facilitated by Spearman's correlation tests. The obtained DLVCs were further cross-validated using a multivariate support-vector-machine (SVM)-based normal tissue complication probability (NTCP) model with an independent testing dataset composed of 8 AE and 13 control patients. RESULTS: We extracted two DLVC constraints. One DLVC was obtained: V (dose/LET boundary: 2.5keV/µm at 75 Gy to 3.2keV/µm at 8.65 Gy) < 1.27% (DLVC1), revealing high LET volume effect. The second DLVC was observed: V(72.2 Gy,0keV/µm) < 2.23% (DVLC2), revealing high dose volume effect. The SVM-based NTCP model with two DLVCs provided slightly superior performance on training, validation, and testing compared to the model using generalized equivalent uniform dose (gEUD) alone (Table 1). The corresponding area-under-the-curves (AUCs) of the receiver operating characteristic (ROC) curve were 0.785 vs. 0.762, 0.720 vs. 0.704, and 0.798 vs. 0.779 for the training, validation, and testing dataset, respectively. Sensitivity of 0.67 and specificity of 0.69 were achieved at the NTCP cutoff value of 0.5 in validation. CONCLUSION: Our results demonstrated the importance of rectal "hot spots" in both high LET (DLVC1) and high dose (DLVC2) in inducing rectal bleeding. The SVM-based NTCP model confirmed the derived DLVCs as good predictors for rectal bleeding. The established NTCP model based on these two DLVCs has been used routinely at our proton center during the plan evaluation to minimize the possible incidence of rectal bleeding in prostate cancer patients treated by IMPT. Table 1 Performances of the NTCP models.

17.
Int J Radiat Oncol Biol Phys ; 111(3S): e388, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34701336

RESUMO

PURPOSE/OBJECTIVE(S): High linear energy transfer (LET) radiotherapy may cause unexpected adverse events (AEs) in head and neck (H&N) cancer patients treated by intensity-modulated proton therapy (IMPT). In this exploratory study, we propose to investigate the effects of LET upon AEs in IMPT using dose-linear-energy-transfer volume histograms (DLVHs) and seed spots analysis. MATERIALS/METHODS: We included 14 H&N patients with unanticipated CTCAEv4.0 grade≥3 AEs for analysis. The AE regions were contoured and the corresponding DLVHs of the AE regions were generated. DLVH was constructed with physical dose (Gy) and LET (keV/µm) as independent variables. The normalized volume of the structure was contoured as iso-volume lines in the dose-LET plane. All voxels in the structure were mapped into the dose-LET plane as dots to see how the dots with similar dose and LET were clustered. For seed spot analysis, we selected voxels at the top edge of the DLVH plots as critical voxels. Individually clustered critical voxels that are geometrically apart were considered as independent seed spots. Median dose/LET from seed spots were extracted. Bivariate-linear-regression models were established for all AEs. The dose and LET product (xBD) volume constraint of osteoradionecrosis was obtained using the receiver operating characteristic curve of 4 osteoradionecrosis patients and 15 additional independent control patients. RESULTS: Dose played a dominant role for in-field AEs such as hemorrhage and ulceration, while LET played an important role in out-of-field AEs such as osteoradionecrosis and mucositis. Intercept-free linear models between the reciprocal of dose and LET were found for different AEs. The corresponding xBD threshold values were included in Table 1. The xBD volume constraint of osteoradionecrosis was derived V (xBD≥275.18 Gy•keV/µm) < 0.0612cc, with an area under curve of 0.85. CONCLUSION: Our observations suggested that dose and LET can contribute to AEs in a complicated fashion. Using the intercept-free bivariate linear regression model, we found a LET-enhancing effect for all 6 AEs included in the study, substantiated by the positive slopes of the empirical dose-LET models. The xBD volume constraint of osteoradionecrosis was derived and showed good performance. We believe that both DLVH and seed spot analysis could be powerful tools for patient outcome studies in IMPT.

18.
Int J Radiat Oncol Biol Phys ; 111(3S): e488, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34701572

RESUMO

PURPOSE/OBJECTIVE(S): Medical assistance in dying (MAID) was legislatively enacted in Canada in June 2016. MAID is performed most frequently for oncology patients. The aim of this study is to describe the patient, disease and process characteristics in this population. MATERIALS/METHODS: We performed a single-institution review of all oncology patients who requested MAID at a tertiary care hospital between June 2016 and June 2020. A prospective database including patient demographics, terminal illness type, dates of assessment, cause of death, and date of death was used. Additional data such as demographic, oncologic, treatment-related, and symptom-related details were retrospectively collected. Descriptive statistics were reported. Our primary hypothesis is that performance status is one of the important factors associated with MAID provision. RESULTS: Between June 2016 and June 2020, 346 oncology patients requested and 103 received MAID. Identifiers were available and data were retrospectively collected for 92/103 patients. Median age was 72 (range 25-97) and 54% were female. The most common primary malignancies were lung (15/92, 16%), pancreaticobiliary (14/92, 16%), colorectal (13/92, 14%), and hematologic malignancy (11/92, 12%). Performance status was documented for 60 patients within 1 week of MAID provision; 90% of patients (54/60) had ECOG performance status of 3 or 4, and 42% patients (25/60) had ECOG performance status of 4. At the time of initial MAID request, 65% of patients (60/92) had metastatic disease, among which 52% of patients (31/60) received palliative-intent systemic therapy. Sixteen percent of patients with metastases (10/60) received at least 3 lines of palliative-intent systemic therapy. Median number of days from first MAID assessment to MAID provision was 7 days (range 0 to 349 days). Sixty-seven percent of patients (60/89) received MAID within 10 days of first MAID assessment and 87% (77/89) within 30 days. The most common debilitating symptoms were uncontrolled pain (53%, 49/92), fatigue (37%, 34/92), and dyspnea (27%, 25/92). CONCLUSION: Ninety percent of oncology patients who received MAID had ECOG performance status of 3 or 4, which is reflective of patients' poor prognosis and limited ability to perform daily activity. The median time interval between first MAID assessment to MAID received was 7 days and most patients received MAID within 30 days.

19.
Int J Radiat Oncol Biol Phys ; 111(3S): e535-e536, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34701688

RESUMO

PURPOSE/OBJECTIVE(S): Daily Cone beam CT (CBCT) imaging provides necessary anatomical information for accurate patient setup. Image quality of CBCT is usually far inferior to simulation CT scans. A workaround is to register the CT to the CBCT such that the contours and Hounsfield Unit (HU) values of the CT can be propagated to the CBCT. However, the inconsistent HU values across CT and CBCT make it less effective to use conventional image similarity measures. We aim to develop an unsupervised registration network to overcome this challenge in multimodal CT-CBCT image registration. MATERIALS/METHODS: We propose to integrate directional local structural similarity into an unsupervised learning framework to perform abdominal CT-CBCT image registration. Directional local structural similarity measures the image's self-similarity which reflects the underlying structural similarity regardless of the modality in use. The CBCT and CT images were separately processed to extract directional local structural similarity feature maps in different directions. We concatenated the directional local structural similarity feature maps and the original images as network input. Taking both the original images and their respective structural similarity feature maps as input allows the network to fully explore the potential correlations between CBCT and CT for accurate deformation vector field (DVF) prediction. Salient features learnt through previous iterations were highlighted by attention gates across layers to expedite the learning process. A 3D bicubic interpolation was used to up-sample and smooth the predicted DVF. We performed a leave-one-out cross validation with an image dataset of 45 patients to evaluate the proposed registration method. Normalized cross correlation (NCC) and target registration error (TRE) between CBCT and deformed CT were calculated to quantify the registration accuracy. RESULTS: Our results show that the alignment between the abdominal soft tissues has been greatly improved after registration for all patients. The mean and standard deviation of NCC and TRE were 0.97 (range 0.95-0.99) and 1.88 (range 1.03-2.67) mm. The proposed network allows for many datasets to be used as training datasets since ground truth DVF is not needed for the training process. The proposed network can predict a final DVF via a single forward prediction, which is faster than the conventional iterative registration algorithms. CONCLUSION: We have developed a novel unsupervised multimodal image registration method for CT-CBCT abdominal image registration, which does not need ground truth DVF for training, and demonstrated its feasibility. Taking both CBCT and CT images and their respective directional local structural similarity features as input, the proposed network performs direct DVF prediction to register the abdominal CT to CBCT images. This tool will be useful for future CBCT-guided radiotherapy of abdominal malignancies.

20.
Angew Chem Int Ed Engl ; 60(49): 25839-25845, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34595813

RESUMO

The active site of [FeFe]-hydrogenase (H2 ase) is preorganized with an amine (azadithiolate) as a proton relay and a [4Fe4S] subunit as an electron reservoir, which together lower the overpotential for proton reduction and hydrogen oxidation by multiple-site concerted proton-electron transfer (MS-CPET). Herein, we report a mononuclear manganese complex, fac-[Mn(CO)3 (6-(2-hydroxyphenol)-2-pyridine-2-quinoline) Br] (1), as a rare model to fully mimic the functions of the H2 ase. In 1, a redox-active bidentate ligand with a pendent phenol replicates the roles of the electron reservoir and the proton relay in the enzyme. Experimental and theoretical studies revealed two consecutive MS-CPET processes in the catalytic cycle, in each of which an electron stored in the reductive ligand and a proton at the proximal phenol moiety are transferred to the Mn center in a concerted way. By virtue of this mechanism, complex 1 exhibited a low overpotential comparable to that of natural enzyme in electrochemical hydrogen production using phenol as a proton source.

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