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1.
Clin Radiol ; 79(6): e842-e853, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38582632

RESUMO

AIM: We design a feasibility study to obtain a set of metabolic-hemodynamic habitats for tackling tumor spatial metabolic patterns with hemodynamic information. MATERIALS AND METHODS: Preoperative data from 69 high-grade gliomas (HGG) patients with subsequent histologic confirmation of HGG were prospectively collected (January 2016 to March 2020) after concurrent chemoradiotherapy (CCRT). Four vascular habitats were automatically segmented by multiparametric magnetic resonance imaging (MRI). The metabolic information, either at enhancing or edema tumor regions, was obtained by two neuroradiologists. The relative habitat volumes were used for weight estimation procedures for computing the coefficients of a linear regression model using weighted least squares (WLS) for metabolite semiquantifications (i.e. the Cho/NAA ratio and the Cho/Cr ratio) at vascular habitats. Multivariate Cox proportional hazard regression analyses are used to obtain the odds ratio (OR) and develop a nomogram using weighted estimators corresponding to each covariate derived from Cox regression coefficients. RESULTS: There was a strongly correlation between perfusion indexes and the Cho/Cr ratio (rCBV, r=0.71) or Cho/NAA ratio (rCBV, r=0.66) at high-angiogenic enhancing tumor habitats (HAT) habitat. Compared isocitrate dehydrogenase (IDH) mutation to their wild type, the IDH wild type had significantly decreased Cho/Cr ratio (IDH mutation: Cho/Cr ratio = 2.44 ± 0.33, IDH wildtype: Cho/Cr ratio = 2.66 ± 0.36, p=0.02) and Cho/NAA ratio (IDH mutation: Cho/Cr ratio = 4.59 ± 0.61, IDH wildtype: Cho/Cr ratio = 4.99 ± 0.66, p=0.022) at the HAT. The C-index for the median progression-free survival (PFS) prediction was 0.769 for the Cho/NAA nomogram and 0.747 for the Cho/Cr nomogram through 1000 bootstrapping validation. CONCLUSIONS: Our findings suggest that spatial metabolism combined with hemodynamic heterogeneity is associated with individual PFS to HGG patients post-CCRT.


Assuntos
Neoplasias Encefálicas , Estudos de Viabilidade , Glioma , Hemodinâmica , Intervalo Livre de Progressão , Humanos , Glioma/diagnóstico por imagem , Glioma/patologia , Glioma/terapia , Feminino , Masculino , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/patologia , Pessoa de Meia-Idade , Hemodinâmica/fisiologia , Adulto , Estudos Prospectivos , Idoso , Imageamento por Ressonância Magnética Multiparamétrica/métodos
2.
Hernia ; 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38687408

RESUMO

PURPOSE: Incarcerated femoral hernia patients had high risk of hernia contents necrosis. We provide our experience of management ischemia and necrosis of hernia contents in emergency incarcerated femoral hernia patients, and to investigate its risk factors. METHODS: This is a case-control study. Eighty-nine incarcerated femoral patients who underwent emergency surgery from January 2015 to December 2021 were included, and divided into normal group (60 cases) and ischemia/necrosis group (29 cases) according to the intraoperative condition of hernia contents. The surgical methods, intraoperative and postoperative conditions were compared between the two groups. Multivariate logistic regression was used to analyze the risk factors of ischemia and necrosis of hernia contents. RESULTS: Open preperitoneal tension-free repair was the most commonly used surgical methods (68.5%) for incarcerated femoral patients. The utilization rate of laparoscopic repair in the ischemia/necrosis group was lower than that in the normal group (13.8% vs. 20.0%, P = 0.475). The proportion of mesh placement in the normal group was significantly higher than that in the ischemia/necrosis group (98.3% vs 65.5%, P < 0.001). The hernia contents resection rate (55.2% vs 1.7%), operation time (90 vs 40 min), intraoperative bleeding (5 vs 2 ml), ICU admission rate (31.0% vs 1.7%), and hospital stay (7 vs 4 d) were significantly higher in the ischemia/necrosis group than those in normal group. Results of multivariate logistic regression showed that incarceration time more than 9 h (aOR = 19.3, 95%CI: 1.9-192.9) was an independent risk factor for ischemia and necrosis of hernia contents in emergency incarcerated femoral hernia patients. CONCLUSION: Open tension-free repair was the most commonly used surgical methods for emergency incarcerated femoral hernia patients. Ischemia and necrosis of hernia contents will increase bowel resection rate and prolong operation and hospital stay. Long incarceration time is an independent risk factor for ischemia and necrosis of hernia contents.

3.
Zhonghua Xue Ye Xue Za Zhi ; 45(1): 28-34, 2024 Jan 14.
Artigo em Chinês | MEDLINE | ID: mdl-38527835

RESUMO

Objective: To evaluate the efficacy of allogeneic hematopoietic stem cell transplantation (allo-HSCT) in young patients with high-risk multiple myeloma (HRMM) and analyzed the factors affecting patient prognosis. Methods: In this retrospective study, we analyzed the clinical data of 14 patients with HRMM with cytogenetic abnormalities or high-risk biological factors who underwent allo-HSCT at the Hematopoietic Stem Cell Transplantation Center of the Institute of Hematology & Blood Diseases Hospital between November 2016 and November 2022. Results: There were seven males and seven females included in the study, with a median age of 39.5 (31-50) years at the time of allo-HSCT. The median number of treatment lines before transplantation was 2 (1-6) . Before allo-HSCT, 42.9% (6/14) of the patients did not achieve complete remission, while 35.7% (5/14) of the patients achieved measurable residual disease positivity. After transplantation, all patients were evaluated for their treatment response, and the overall response rate was 100% (14/14) . All 14 patients successfully underwent allo-HSCT, with median engraftment times for neutrophils and platelets of 11 (10-14) days and 13 (9-103) days, respectively. Acute grade Ⅱ-Ⅳ graft-versus-host disease (GVHD) occurred in five patients (35.7%) , and two patients (14.3%) developed moderate-to-severe chronic GVHD. The median follow-up time after allo-HSCT was 18.93 (4.10-72.53) months, with an expected 2-year transplant-related mortality rate of 7.1% (95% CI 0%-21.1%) and an expected 2-year overall survival rate of 92.9% (95% CI 80.3%-100.0%) . Moreover, the expected 1-year and 2-year progression-free survival rates were 92.9% (95% CI 80.3%-100.0%) and 66.0% (95% CI 39.4%-100.0%) , respectively, and the 2-year cumulative incidence of relapse was 28.9% (95% CI 0%-56.7%) . Upfront allo-HSCT following complete remission after induced therapy and the presence of chronic GVHD might be favorable prognostic factors. Conclusion: allo-HSCT is an effective treatment for improving the prognosis of young patients with HRMM.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Mieloma Múltiplo , Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Mieloma Múltiplo/terapia , Estudos Retrospectivos , Recidiva Local de Neoplasia/complicações , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Doença Enxerto-Hospedeiro/etiologia
4.
Artigo em Chinês | MEDLINE | ID: mdl-38548395

RESUMO

Objective: To investigate the early clinical characteristics of elderly patients with severe burns and the risk factors on prognosis. Methods: This study was a retrospective case series study. Clinical data of 124 elderly patients with severe burns who met the inclusion criteria and were admitted to the 12 hospitals from January 2015 to December 2020 were collected, including 4 patients from the Fourth People's Hospital of Dalian, 5 patients from Fujian Medical University Union Hospital, 22 patients from Guangzhou Red Cross Hospital of Jinan University, 5 patients from Heilongjiang Provincial Hospital, 27 patients from the First Affiliated Hospital of Naval Medical University, 9 patients from the First Affiliated Hospital of Nanchang University, 10 patients from Affiliated Hospital of Nantong University, 9 patients from Tongren Hospital of Wuhan University & Wuhan Third Hospital, 12 patients from the 924th Hospital of PLA, 6 patients from Zhangjiagang First People's Hospital, 4 patients from Taizhou Hospital of Zhejiang Province, and 11 patients from Zhengzhou First People's Hospital. The patients' overall clinical characteristics, such as gender, age, body mass index, total burn area, full-thickness burn area, inhalation injury, causative factors, whether combined with underlying medical diseases, and admission time after injury were recorded. According to the survival outcome within 28 days after injury, the patients were divided into survival group (89 cases) and death group (35 cases). The following data of patients were compared between the two groups, including the basic data and injuries (the same as the overall clinical characteristics ahead); the coagulation indexes within the first 24 hours of injury such as prothrombin time (PT), activated partial thromboplastin time (APTT), thrombin time, D-dimer, fibrinogen degradation product (FDP), international normalized ratio (INR), and fibrinogen; the blood routine indexes within the first 24 hours of injury such as white blood cell count, platelet count, neutrophil-to-lymphocyte ratio, monocyte count, red blood cell count, hemoglobin, and hematocrit; the organ function indexes within the first 24 hours of injury such as direct bilirubin, total bilirubin, urea, serum creatinine, aspartate aminotransferase, alanine aminotransferase, total protein, albumin, globulin, blood glucose, triglyceride, total cholesterol, alkaline phosphatase, creatine kinase, electrolyte indexes (potassium, sodium, chlorine, calcium, magnesium, and phosphorus in blood), uric acid, myoglobin, and brain natriuretic peptide; the infection and blood gas indexes within the first 24 hours of injury such as procalcitonin, C-reactive protein, pH value, oxygenation index, base excess, and lactate; treatment such as whether conducted with mechanical ventilation, whether conducted with continuous renal replacement therapy, whether conducted with anticoagulation therapy, whether applied with vasoactive drugs, and fluid resuscitation. The analysis was conducted to screen the independent risk factors for the mortality within 28 days after injury in elderly patients with severe burns. Results: Among 124 patients, there were 82 males and 42 females, aged 60-97 years, with body mass index of 23.44 (21.09, 25.95) kg/m2, total burn area of 54.00% (42.00%, 75.00%) total body surface area (TBSA), and full-thickness burn area of 25.00% (10.00%, 40.00%) TBSA. The patients were mainly combined with moderate to severe inhalation injury and caused by flame burns. There were 43 cases with underlying medical diseases. The majority of patients were admitted to the hospital within 8 hours after injury. There were statistically significant differences between patients in the 2 groups in terms of age, total burn area, full-thickness burn area, and inhalation injury, and PT, APTT, D-dimer, FDP, INR, white blood cell count, platelet count, urea, serum creatinine, blood glucose, blood sodium, uric acid, myoglobin, and urine volume within the first 24 hours of injury (with Z values of 2.37, 5.49, 5.26, 5.97, 2.18, 1.95, 2.68, 2.68, 2.51, 2.82, 2.14, 3.40, 5.31, 3.41, 2.35, 3.81, 2.16, and -3.82, respectively, P<0.05); there were statistically significant differences between two groups of patients in whether conducted with mechanical ventilation and whether applied with vasoactive drugs (with χ2 values of 9.44 and 28.50, respectively, P<0.05). Age, total burn area, full-thickness burn area, serum creatinine within the first 24 hours of injury, and APTT within the first 24 hours of injury were the independent risk factors for the mortality within 28 days after injury in elderly patients with severe burns (with odds ratios of 1.17, 1.10, 1.10, 1.09, and 1.27, 95% confidence intervals of 1.03-1.40, 1.04-1.21, 1.05-1.19, 1.05-1.17, and 1.07-1.69, respectively, P<0.05). Conclusions: The elderly patients with severe burns had the injuries mainly from flame burns, often accompanied by moderate to severe inhalation injury and enhanced inflammatory response, elevated blood glucose levels, activated fibrinolysis, and impaired organ function in the early stage, which are associated with their prognosis. Age, total burn area, full-thickness burn area, and serum creatinine and APTT within the first 24 hours of injury are the independent risk factors for death within 28 days after injury in this population.


Assuntos
Glicemia , Queimaduras , Masculino , Idoso , Feminino , Humanos , Estudos Retrospectivos , Creatinina , Mioglobina , Ácido Úrico , Prognóstico , Queimaduras/diagnóstico , Ácido Láctico , Produtos de Degradação da Fibrina e do Fibrinogênio , Fatores de Risco , Bilirrubina , Sódio , Ureia
5.
Zhonghua Wai Ke Za Zhi ; 62(5): 412-418, 2024 May 01.
Artigo em Chinês | MEDLINE | ID: mdl-38548610

RESUMO

Objective: To investigate the surgical strategy for chronic pancreatitis complicated with suspected malignant lesions in the pancreatic head and pancreatolithiasis in the distal pancreas. Methods: This is a retrospective cohort study. Clinical data from 11 patients with chronic pancreatitis who underwent pancreaticoduodenectomy combined with longitudinal pancreaticojejunostomy(PD-L) were retrospectively collected(PD-L group) from the Department of Hepatobiliary Surgery of the First Affiliated Hospital of Xi'an Jiaotong University between December 2021 and September 2023. All patients were male with an age of (49.0±11.2) years(range:32 to 70 years). Their primary preoperative diagnoses included pancreatic lesions, chronic pancreatitis, pancreatolithiasis, and dilatation of the pancreatic duct. Data from 248 patients who underwent pancreaticoduodenectomy(PD) during the same period were retrospectively collected(PD group). There were 157 males and 91 females in the PD group, with an age of (61.5±10.8) years(range:27 to 82 years). Among them, 87 cases were diagnosed as pancreatic cancer or chronic pancreatitis. The propensity score matching method was used to reduce confounding bias between the two groups. The caliper value of 0.1 was used and the 1∶4 nearest neighbor matching method was used for the matching. Comparisons between the two groups were made using the independent sample t test, Mann-Whitney U test or χ2 test,respectively. Results: After complete excision of the specimen during pancreaticoduodenectomy, the key surgical step of PD-L was longitudinal pancreaticojejunostomy in the remaining pancreas. Intraoperative blood loss in the PD-L group was lower than that in the PD group [M(IQR)](300(200)ml vs. 500(500)ml, respectively; P<0.05). Similarly, hospitalization days(21.0(7.0)days vs. 25.0(8.5)days) and postoperative hospitalization days(13.0(8.0)days vs. 17.0(5.0) days) were also lower in the PD-L group compared to the PD group (P<0.05). There were no significant differences in the operation time and postoperative complication rate between the two groups(P>0.05). In the PD-L group, the postoperative follow-up time was 5(5)months(range: 3 to 21 months). One case was lost for follow-up. Abdominal pain was relieved in 10 patients. Additionally, abdominal distension and steatosis were alleviated in 8 cases. Furthermore, 5 cases of diabetes mellitus showed improved control of HbA1c and fasting blood glucose levels after surgery. Conclusions: PD-L treatment can be used to treat chronic pancreatitis complicated by suspected malignant lesions in the pancreatic head and pancreatolithiasis in the distal pancreas. PD-L also has advantages in removing stones from the pancreatic duct and evaporation of pancreatic fluid. However, due to the single-center design and the small sample size of this study, further practice and long-term follow-up are still necessary.


Assuntos
Pancreaticoduodenectomia , Pancreaticojejunostomia , Pancreatite Crônica , Humanos , Pancreaticoduodenectomia/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Pancreatite Crônica/cirurgia , Feminino , Adulto , Idoso , Pancreaticojejunostomia/métodos , Resultado do Tratamento , Idoso de 80 Anos ou mais , Pâncreas/cirurgia , Neoplasias Pancreáticas/cirurgia , Ductos Pancreáticos/cirurgia
6.
Artigo em Chinês | MEDLINE | ID: mdl-38418179

RESUMO

Objective: To investigate the clinical effect of anterolateral thigh flow-through chimeric perforator free flap transplantation in the treatment of upper limb complex tissue defects with main artery injury. Methods: The study was a retrospective observational study. From May 2019 to January 2022, 11 patients with upper limb complex tissue defects combined with main artery injury who met the inclusion criteria were admitted to the Department of Hand, Foot and Ankle Surgery of General Hospital of Ningxia Medical University, including 7 males and 4 females, aged from 18 to 56 years. After debridement, the area of skin and soft tissue defects was from 20 cm×6 cm to 32 cm×10 cm, and the exposed area of dead cavity or deep tissue was from 7 cm×4 cm to 10 cm×7 cm. Three patients had radial artery defects with a length of 4 to 7 cm; two patients had ulnar artery defects with a length of 5 to 8 cm; 4 patients had defects in both ulnar and radial arteries with a length of 3 to 7 cm; and in two patients, the ulnar, radial and brachial arteries were all defective with a length of 4 to 8 cm. The anterolateral thigh flow-through chimeric perforator flap was designed and cut. The skin flap area was from 22 cm×7 cm to 32 cm×11 cm, the chimeric muscle flap area was from 7 cm×4 cm to 10 cm×7 cm, and the length of the flow-through vessel in the "T" shaped vessel pedicle was from 4 to 8 cm. When transplanting the skin flap, the proximal end of the vascular pedicle was anastomosed with the proximal end of the recipient site, and the distal end of the vascular pedicle was anastomosed with the more normal blood vessel at the distal end of the forearm; the invalid cavity was filled with the muscle flap. The donor site wounds of tissue flap were closed directly or treated with skin grafting. After operation, the blood supply and survival of the flap, the survival of the distal limb, and the survival of the skin graft at the flap donor site were observed. Computed tomography angiography (CTA) was performed to observe the patency of the proximal and distal anastomotic arteries from 2 to 4 weeks after surgery. During follow-up, the texture of the flap, the survival of the grafted skin and the healing of the donor area were observed. Results: One patient (complete forearm disconnection) developed distal limb blood disorder on 5 days after surgery. CTA examination suggested embolization of the distal anastomosis of the flow-through artery. more muscle and skin and soft tissue necrosis of the distal limb showed in emergency exploration. So, amputation was performed ultimately. No vascular crisis occurred in the skin flaps of the remaining 10 patients, and all skin flaps, distal limbs and the skin grafts in flap donor sites survived well. Two to 4 weeks after surgery, the proximal and distal ends of the anastomosed arteries were good in the patency. Follow-up for 11-37 months, the flap texture was good, and all donor site wounds healed well. Conclusions: The use of anterolateral thigh flow-through chimeric perforator flap to repair upper limb complex tissue defects accompanied by main artery injury can improve the success rate of limb salvage, which can be promoted in clinical practice.


Assuntos
Retalhos de Tecido Biológico , Procedimentos de Cirurgia Plástica , Lesões dos Tecidos Moles , Feminino , Humanos , Masculino , Artéria Braquial/cirurgia , Retalhos de Tecido Biológico/cirurgia , Transplante de Pele , Lesões dos Tecidos Moles/cirurgia , Coxa da Perna/cirurgia , Resultado do Tratamento , Extremidade Superior/cirurgia , Estudos Retrospectivos
7.
Hernia ; 28(1): 119-126, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37848581

RESUMO

PURPOSE: Patients with liver cirrhosis sometimes suffer from high recurrence rates and postoperative complications. We previously reported that platelet-related hematological parameters are associated with the outcomes after incisional herniorrhaphy, and aim to evaluate the predictive value of these criteria in cirrhotic patients undergoing open umbilical herniorrhaphy. METHODS: This is a retrospective study. The data of 95 cirrhotic patients undergoing open umbilical herniorrhaphy were analyzed. Patients were grouped based on the recurrence and defined hematological values. Platelet-multiple-lymphocyte index (PLM), neutrophil-leukocyte ratio, lymphocyte-monocyte ratio, platelet-neutrophil ratio, systemic immune-inflammation index, and aspartate aminotransferase-leukocyte ratio values were calculated based on preoperative blood analyses. The outcomes were obtained from hospital records and follow-up calls to patients. RESULTS: Using cutoff values acquired by the Youden Index, we found a PLM value < 27.9, and the history of inguinal herniorrhaphy were revealed to be statistically significant in the recurrence based on univariant and multivariant analyses (p < 0.05). We further divided patients into two groups based on the cutoff value of PLM and found that a PLM value < 27.9 was significantly associated with the recurrence of incisional hernias (p = 0.018) and the occurrence of postoperative foreign sensation (p = 0.044), and tended to result in other postoperative complications such as cardiopathy, respiratory infection, hypoproteinemia, and hepatic diseases (p = 0.089). CONCLUSION: The preoperative hematological values, especially PLM, may indicate the outcomes in cirrhotic patients after open umbilical herniorrhaphy. Accurate identification of risks may alert the intraoperative and postoperative care for patients.


Assuntos
Hérnia Umbilical , Humanos , Hérnia Umbilical/complicações , Hérnia Umbilical/cirurgia , Estudos Retrospectivos , Herniorrafia/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Cirrose Hepática/complicações , Cirrose Hepática/cirurgia
8.
J Endocrinol Invest ; 47(1): 115-129, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37294407

RESUMO

BACKGROUND: We aimed to develop a nomogram model of overall survival (OS) and cancer-specific survival (CSS) in patients with differentiated thyroid cancer with distant metastases, and to evaluate and validate the nomogram. Also, its prognostic value was compared with that of the 8th edition of the American Joint Committee on Cancer tumor-node-metastasis staging system (AJCC8SS). METHODS: Patients with distant metastatic differentiated thyroid cancer (DMDTC) from 2004 to 2015 were selected from the Surveillance, Epidemiology, and End Results (SEER) Program to extract the clinical variables used for analysis. A total of 906 patients were divided into a training set (n = 634) and validation set (n = 272). OS and CSS were selected as the primary end point and secondary end point. LASSO regression analysis and multivariate Cox regression analysis were applied to screen variables for constructing OS and CSS nomograms for survival probability at 3, 5, and 10 years. Nomograms were evaluated and validated using the consistency index (C-index), time-dependent receiver operator characteristic (ROC) curves, area under the ROC curve, calibration curves, and decision curve analysis (DCA). The predictive survival of the nomogram was compared with that of AJCC8SS. Kaplan-Meier curves and log-rank tests were used to evaluate the risk-stratification ability OS and CSS nomograms. RESULTS: CS and CSS nomograms included six independent predictors: age, marital status, type of surgical procedure, lymphadenectomy, radiotherapy, and T stage. The C-index for the OS nomogram was 0.7474 (95% CI = 0.7199-0.775), and that for the CSS nomogram was 0.7572 (0.7281-0.7862). The nomogram showed good agreement with the "ideal" calibration curve in the training set and validation sets. DCA confirmed that the survival probability predicted by the nomogram had high clinical predictive value. The nomogram could stratify patients more accurately, and showed more robust accuracy and predictive power, than AJCC8SS. CONCLUSIONS: We established and validated prognostic nomograms for patients with DMDTC, which had significant clinical value compared with AJCC8SS.


Assuntos
Adenocarcinoma , Neoplasias da Glândula Tireoide , Humanos , Nomogramas , Programa de SEER , Neoplasias da Glândula Tireoide/terapia , Prognóstico , Estadiamento de Neoplasias
9.
Zhonghua Yi Xue Za Zhi ; 103(45): 3665-3669, 2023 Dec 05.
Artigo em Chinês | MEDLINE | ID: mdl-38018066

RESUMO

Objective: To evaluate the efficacy and safety of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for the treatment of primary myelofibrosis (PMF) patients. Methods: A total of 14 cases of PMF who underwent allo-HSCT from December 2008 to December 2022 were analyzed retrospectively, including 8 males and 6 females with a median age [M(Q1, Q3)]of 36 (24, 42) years. Three-year overall survival (OS), disease free survival (DFS), cumulative incidence of relapse (CIR), transplantation-related mortality (TRM) were analyzed. Meanwhile, the complications were followed up by telephone and outpatient appointments for 49.6 (9.0,93.1) months. Results: All patients received myeloablative conditioning regimens (MAC). All patients had successful engraftment, and the median time of neutrophils and platelet engraftment were 13.5 (11.8, 18.0) days and 19.5 (13.5, 24.5) days, respectively. Ⅱ-Ⅳ acute graft versus host disease (GVHD) occurred in 3 cases, while chronic GVHD in 8 cases. The rate of 3-year OS,DFS,CIR and TRM were (92.9±6.9)%, (76.0±12.2)%, (38.6±2.7)% and (7.1±0.5)% respectively after a median follow-up time of 1 489.0 (270.3,2 794.8) days. Two patients died from treatment-related complications, one of which died 39 days after transplantation due to heart failure caused by severe anemia, the other patient died 6 years after relapse due to pulmonary infection. Conclusion: Allo-HSCT can be used as a safe and effective approach to treat PMF.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Mielofibrose Primária , Masculino , Feminino , Humanos , Estudos Retrospectivos , Mielofibrose Primária/terapia , Recidiva , Condicionamento Pré-Transplante
10.
Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi ; 41(10): 850-854, 2023 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-37935553

RESUMO

Objective: To establish a automatic headspace gas chromatography-mass spectrometry (HS/GC-MS) method for the determination of 14 volatile organic compounds in urine. Methods: In September 2022, 10 ml urine sample was taken into a 20 ml headspace bottle, balanced for 30 min at 65 ℃, and then detected by HS/GC-MS and quantified by external standard method. Results: The 14 volatile organic compounds showed good linearity at 0.2-8.0 µg/L and 0.1-4.0 µg/L, with correlation coefficients ranging from 0.9956-0.9999. The recoveries were 79.8%-113.1% with relative standard deviations 0.05%-0.27% when three different concentration levels were added. Detection limit was 0.03-0.05 µg/L. Conclusion: The method is simple and convenient, and the recovery and precision meet the requirements. It can be used for the determination of common volatile organic compounds in urine.


Assuntos
Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos Orgânicos Voláteis/análise
11.
Artigo em Chinês | MEDLINE | ID: mdl-37805739

RESUMO

Objective: To conduct a visual analysis of the literature on burn-related coagulation dysfunction and to explore the current research status, evolution process, hot topics, and future research trends in burn-related coagulation dysfunction at home and abroad. Methods: The bibliometrics method was used. The literature on burn-related coagulation dysfunction which were published in Web of Science and China National Knowledge Internet databases from January 1, 1950 to May 1, 2022, and met the inclusion criteria were retrieved for publication volume analysis. The literature on burn-related coagulation dysfunction were retrieved as above in the core collection of Web of Science and China National Knowledge Internet databases, and CiteSpace 5.8.R3 software was used to perform co-occurrence analysis, cluster analysis, and literature co-citation analysis of key words. Results: A total of 501 and 235 literature on burn-related coagulation dysfunction were retrieved from Web of Science database and China National Knowledge Internet database, respectively. The literature on burn-related coagulation dysfunction emerged from 1975 and 1950, respectively, in China and abroad, which were gradually increased later. The frequency and centrality of Chinese key words such as , , were high in 235 literature in China National Knowledge Internet database, and the frequency and centrality of key words such as burn, coagulation, and deep vein thrombosis were high in 340 literature in the core collection of Web of Science database. In China National Knowledge Internet database, the top 6 Chinese key words in terms of burst intensity were , , , , , , and the first 3 among which were burst key words in the early stage; and in the core collection of Web of Science database, the key words with higher burst intensity were disseminated intravascular coagulation and pulmonary embolism, which were the burst key words in the early stage. The representative clustering labels in China National Knowledge Internet database were #0 , #1 , and #2 , etc., and the representative clustering labels in the core collection of Web of Science database were #0 risk, #1 surgical patient, and #2 sepsis. Early researches in China National Knowledge Internet database and the core collection of Web of Science database focused on the presence of burn-related coagulation dysfunction itself, while the late researches focused on the relationship between burn-related coagulation dysfunction and inflammation, immunity, coagulation in general, and wounds. From 2010 onwards, there were a large number of core cited literature in the core collection of Web of Science database, and the prevention and treatment of vein thromboembolism was the most popular research direction in recent years. The researches on optimization and standardization of diagnostic methods and the overall mechanism of burn-related coagulation dysfunction would be the main research directions in the future. Conclusions: The research hotspots and evolution processes of burn-related coagulation dysfunction at home and abroad have both similarities and differences, and the current research hotspot is the relationship between coagulation and inflammation, immunity. With researches increasingly deepening, the researches on optimization and standardization of diagnostic methods and the overall mechanism of burn-related coagulation dysfunction will be the main research directions in the future.


Assuntos
Transtornos da Coagulação Sanguínea , Queimaduras , Humanos , Inflamação , Queimaduras/complicações , Bibliometria , China
12.
Zhonghua Xue Ye Xue Za Zhi ; 44(8): 628-634, 2023 Aug 14.
Artigo em Chinês | MEDLINE | ID: mdl-37803835

RESUMO

Objective: To evaluate the efficacy and safety of HLA-haploidentical hematopoietic stem cell transplantation (allo-HSCT) for hepatitis-related aplastic anemia (HRAA) patients. Methods: Retrospective analysis was performed on hepatitis-associated aplastic anemia patients who received haplo-HSCT at our center between January 2012 and June 2022. October 30, 2022 was the final date of follow-up. Results: This study included 28 HRAA patients receiving allo-HSCT, including 18 males (64.3% ) and 10 females (35.7% ), with a median age of 25.5 (9-44) years. About 17 cases of severe aplastic anemia (SAA), 10 cases of very severe aplastic anemia (VSAA), and 1 case of transfusion-dependent aplastic anemia (TD-NSAA) were identified. Among 28 patients, 15 patients received haplo-HSCT, and 13 received MSD-HSCT. The 2-year overall survival (OS) rate, the 2-year failure-free survival (FFS) rate, the 2-year transplant-related mortality (TRM) rate, the 100-day grade Ⅱ-Ⅳ acute graft-versus-host disease (aGVHD) cumulative incidence rate, and the 2-year chronic graft-versus-host disease (cGVHD) cumulative incidence rate were 81.4%, 81.4% (95% CI 10.5% -20.6% ), 14.6% (95% CI 5.7% -34.3% ), 25.0% (95% CI 12.8% -45.4% ), and 4.2% (95% CI 0.6% -25.4% ), respectively. After transplantation, all patients had no significant liver function damage. Compared with the MSD-HSCT group, only the incidence of cytomegaloviremia was significantly higher in the haplo-HSCT group [60.0% (95% CI 35.2% -84.8% ) vs 7.7% (95% CI 0-22.2% ), P=0.004]. No statistically significant difference in the Epstein-Barr virus was found in the 2-year OS, 2-year FFS, 2-year TRM, and 100-day grade Ⅱ-Ⅳ aGVHD cumulative incidence rates and 2-year cGVHD cumulative incidence rate. Conclusion: Allo-HSCT is safe and effective for HRAA, and haplo-HSCT can be used as a safe and effective alternative for newly diagnosed HRAA patients who cannot obtain HLA-matched sibling donors.


Assuntos
Anemia Aplástica , Síndrome de Bronquiolite Obliterante , Infecções por Vírus Epstein-Barr , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Hepatite , Masculino , Feminino , Humanos , Adulto , Resultado do Tratamento , Anemia Aplástica/terapia , Estudos Retrospectivos , Herpesvirus Humano 4 , Doença Enxerto-Hospedeiro/epidemiologia , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Hepatite/etiologia , Condicionamento Pré-Transplante
13.
Nan Fang Yi Ke Da Xue Xue Bao ; 43(9): 1469-1475, 2023 Sep 20.
Artigo em Chinês | MEDLINE | ID: mdl-37814860

RESUMO

OBJECTIVE: To investigate whether long noncoding RNA H19 (lncRNA H19) induces vascular calcification by promoting calcium deposition, osteogenic differentiation and apoptosis via inhibiting the Bax inhibitor 1/optic atrophy 1 (BI-1/ OPA1) pathway. METHODS: ß-glycerophosphate and calcium chloride were used to induce calcification in rat vascular smooth muscle cells (VSMCs), and the effects of siH19, alone or in combination with BI-1 or OPA1 knockdown, on calcification of the cells were investigated. Osteogenic differentiation was assessed by measuring Runt-related transcription factor 2 (Runx-2) and bone morphogenetic protein 2 (BMP-2) expression with Western blotting, and cell apoptosis was evaluated by TUNEL staining and Western blotting. An ApoE-/- diabetic mouse model with high-fat feeding for 32 weeks were given an intraperitoneal injection of siH19, and the changes in calcium deposition in the aortic arch were examined using Alizarin red S staining and von Kossa staining. RESULTS: In rat VSMCs with calcification, the expression of lncRNA H19 was significantly increased, and the expressions of BI- 1 and OPA1 were significantly decreased. Downregulation of lncRNA H19 significantly increased the expressions of BI-1 and OPA1 proteins in the cells, and BI-1 knockdown further reduced OPA1 expression (P<0.001). The cells treated with siH19 showed total disappearance of the calcified nodules with significantly reduced expressions of Runx-2, BMP-2 and cleaved caspase-3 and a lowered cell apoptosis rate (P<0.001). Calcified nodules were again observed in the cells with lncRNA H19 knockdown combined with BI-1 or OPA1 knockdown, and the expressions of Runx-2, BMP-2, cleaved-caspase-3 and cell apoptosis rate all significantly increased (P<0.001). In the diabetic mouse model with high-fat feeding, siH19 treatment significantly reduced the calcification area and increased mRNA expressions of BI-I and OPA1 in the aortic arch. CONCLUSION: LncRNA H19 promotes vascular calcification possibly by promoting calcium deposition, osteogenic differentiation and cell apoptosis via inhibiting the BI-1/OPA1 pathway.


Assuntos
Diabetes Mellitus , Atrofia Óptica Autossômica Dominante , RNA Longo não Codificante , Calcificação Vascular , Animais , Camundongos , Ratos , Proteína X Associada a bcl-2/metabolismo , Cálcio/metabolismo , Caspase 3/metabolismo , Células Cultivadas , Diabetes Mellitus/metabolismo , Modelos Animais de Doenças , Miócitos de Músculo Liso , Atrofia Óptica Autossômica Dominante/metabolismo , Osteogênese , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Calcificação Vascular/metabolismo
14.
Zhonghua Liu Xing Bing Xue Za Zhi ; 44(9): 1358-1362, 2023 Sep 10.
Artigo em Chinês | MEDLINE | ID: mdl-37743266

RESUMO

Objective: To investigate the prevalence of syphilis in HIV-infected patients with transmission risk and influencing factors in Zhejiang Province. Method: The information about the HIV-infected patients, who were alive, had been diagnosed with HIV for >1 year, had received no antiviral treatment or had HIV viral load ≥50 copies/ml, and were aged ≥15 years, reported in Zhejiang as of December 31, 2018 were collected from China Information System for Disease Control and Prevention. The information included general demographic characteristics, sexual behavior characteristics and antiretroviral therapy and syphilis serological test results. The prevalence of syphilis and the influencing factors were analyzed by logistic regression model. The SPSS 19.0 software was used for statistical analysis. Results: A total of 2 275 HIV-infected patients were at risk of HIV transmission, and 75.5% (1 717/2 275) of them were tested for syphilis, the prevalence rate of syphilis was 8.7% (150/1 717). Among the HIV-infected patients with syphilis, 11.3% (17/150) received no antiviral treatment, 38.7% (58/150) had viral load of 50-999 copies/ml and 50.0% (75/150) had ≥1 000 copies/ml. Multivariate logistic regression analysis showed that being men (aOR=2.04, 95%CI:1.06-3.96), homosexual transmission (aOR=1.53, 95%CI:1.04-2.27), history of sexually transmitted diseases (STDs) before HIV diagnosis (aOR=1.98, 95%CI:1.35-2.92) and HIV viral load ≥1 000 copies/ml (aOR=1.90, 95%CI:1.09-3.30) were the risk factors for syphilis. Marriage (aOR=0.47, 95%CI: 0.29-0.76) was a protective factor for syphilis. Conclusions: The prevalence of syphilis was high in HIV-infected patients with transmission risk in Zhejiang. It is urgent to carry out classified management and targeted intervention in HIV-infected patients, explore multi-disease prevention and treatment mechanism, strengthen syphilis screening and treatment in HIV-infected patients to reduce the transmission of HIV and syphilis.


Assuntos
Sífilis , Masculino , Humanos , Feminino , Sífilis/epidemiologia , Prevalência , Fatores de Risco , Antivirais , China/epidemiologia
15.
Artigo em Chinês | MEDLINE | ID: mdl-37675527

RESUMO

Objective: To investigate the characteristics of nasal flora and the pathogenic role of differential microbiome in patients with allergic rhinitis (AR) and non-allergic rhinitis (nAR). Methods: Thirty-five patients with AR who attended the rhinology outpatient clinic of the Second Hospital of Harbin Medical University from February to July 2022 were selected. A total of 35 nAR patients were selected as the test group, and 20 cases of healthy people with physical examination at the same period were selected as the control group, including 39 males and 51 females, aged 8 to 55 years. 16SrDNA High-throughput sequencing was used to analyze the relative abundance from nasal flora in the three groups of subjects. Alpha diversity index analysis was conducted with R software, and differences between groups were analyzed with LEfSe, Metastats, and t tests. At the same time, the role of microbiome and its relationship with environmental factors were analyzed with R software. Results: There was a significant difference in the bacterial composition of the samples from the three groups, with the relative abundance of Staphylococcus aureus (P=0.032) and Corynebacterium proinquum (P=0.032) within the AR group being significantly higher than that of the nAR group, and that of Lactobacillus murinus, Lactobacillus kunkeei, and Alcaligenes faecalis (P value was 0.016, 0.005, and 0.001, respectively) being significantly lower than that of the nAR group. The relative abundance of Ackermannia muciniphila within the nAR group was higher than that of the control group (P=0.009). Correlation analysis of environmental factors showed a negative correlation between Lactobacillus kunkeei and IgE (P=0.044), and a positive correlation between Lactobacillus murinus and age (P=0.019). AR and nAR random forest prediction models were constructed for the five genera, respectively, and the area under the curve (AUC) of the models of Streptococcus-SP-FF10, Pseudoalteromonas luteoviolacea, Pseudomonas parafulva, Acinetobacter ursingii, and Azotobacter chroococcum in the AR group was 100% (95%CI: 100% to 100%). The AUC for the Pseudomonas parafulva, Azotobacter chroococcum, Closoridium baratii, Turicibacter-SP-H121, and Streptococcus lutetiensis models in the nAR group was 98.4% (95%CI: 94.9% to 100%). Conclusions: The distribution of nasal flora in AR patients, nAR patients and healthy subjects is significantly different, and the changes of bacterial flora abundance are significantly related to the occurrence of AR and nAR. Combined detection of microbiota has the potential to diagnose AR and nAR patients.


Assuntos
Rinite Alérgica , Rinite , Feminino , Masculino , Humanos
16.
Beijing Da Xue Xue Bao Yi Xue Ban ; 55(4): 743-747, 2023 Aug 18.
Artigo em Chinês | MEDLINE | ID: mdl-37534661

RESUMO

OBJECTIVE: To summarize and analyze the clinical characteristics of patients diagnosed with hepatic portal venous gas (HPVG). METHODS: This was a single center retrospective observational study. All of the patients were diagnosed with HPVG. The patients were admitted to Peking University Third Hospital from January 2017 to January 2021. Demographic characteristics, clinical manifestations, laboratory tests, abdominal imaging, treatment of the primary disease, and clinical outcomes of the patients were collected via electronic medical records. The study was approved by institutional review board and the information of all the patients was kept de-identified. RESULTS: A total of seven cases were included in the study. The median age of the patients was 67 (63, 81) years. Six of the patients were male. The seven patients all presented with sudden onset of severe abdominal pain, which was the most common symptom. Six patients developed septic shock after admission. The signs of HPVG were detected by CT scans in all the patients, showing gas embolization. It might also be found as unique "aquarium sign" in abdominal ultrosonography. Four cases were caused by intestinal lesions, including acute volvulus, intestinal obstruction, and rectal abscess. Two were caused by ischemic bowel disease and the other one was caused by severe acute pancreatitis. The gas accumulation could disappear after effective anti-shock therapy and surgery (Cases 1, 2, and 6). Two patients had good postoperative outcomes, and one patient was discharged after non-surgical treatment. However, the prognosis was poor in the patients with intestinal ischemia necrosis accompanied by shock and multiple organ dysfunction (Cases 3, 4, 5, and 7 all died). CONCLUSION: The HPVG patients generally have acute abdominal pain and show up at Emergency Department. The prognosis depends on the potential cause of HPVG. The mechanism and clinical management for the appearance of gas in the portal vein is not well understood. Patients complicated with shock, ascites, and peritonitis may have intestinal necrosis, which indicates surgical intervention and higher mortality. CT is the preferred diagnostic method in standard clinical practice. Physicians need to have a comprehensive understanding of the proactive diagnostic strategy, and active treatment for the primary disease.


Assuntos
Pancreatite , Doenças Vasculares , Humanos , Masculino , Feminino , Doença Aguda , Veia Porta , Doenças Vasculares/complicações , Doenças Vasculares/diagnóstico , Doenças Vasculares/terapia , Necrose , Dor Abdominal
17.
Zhonghua Xue Ye Xue Za Zhi ; 44(6): 472-478, 2023 Jun 14.
Artigo em Chinês | MEDLINE | ID: mdl-37550202

RESUMO

Objective: To investigate the early effect and safety of allogeneic hematopoietic stem cell transplantation (allo-HSCT) with a 10-day decitabine-containing conditioning regimen in the treatment of acute myeloid leukemia (AML) /myelodysplastic syndrome (MDS) . Methods: From April 2021 to May 2022, 31 AML/MDS patients who received allo-HSCT with a 10-day decitabine-containing conditioning regimen were analyzed. Results: AML (n=10), MDS-AML (n=6), CMML-AML (n=1), and MDS (n=14) were identified in 31 patients, 16 males, and 15 females, with a median age of 41 (20-55) yr. Neutrophils and platelets were successfully implanted in 31 patients (100%), with a median implantation duration of 12 (9-30) and 14 (9-42) days, respectively. During the preconditioning period, 16 patients (51.6%) developed oral mucositis, with 15 cases of Ⅰ/Ⅱ grade (48.4%) and one case of Ⅲ grade (3.2%). After transplantation, 13 patients (41.9%) developed CMV viremia, six patients (19.4%) developed hemorrhagic cystitis, and four patients (12.9%) developed a local infection. The median time of acute graft versus host disease (aGVHD) following transplantation was 33 (12-111) days. The cumulative incidence of aGVHD and Ⅲ/Ⅳ grade aGVHD was 41.9% (95% CI 26.9%-61.0%) and 22.9% (95% CI 13.5%-47.5%), respectively. There was no severe cGVHD, and mild and moderate chronic GVHD (cGVHD) incidence was 23.5% (95% CI 12.1%-43.6%). As of November 30, 2022, only one of the 31 patients had relapsed, with a 1-yr cumulative relapse rate (CIR) of 3.2% (95% CI 0.5%-20.7%). There was only one relapse patient death and no non-relapse deaths. The 1-yr overall survival (OS) and disease-free survival (DFS) rates were 92.9% (95% CI 80.3%-100%) and 96.8% (95% CI 90.8%-100%), respectively. Conclusions: A 10-day decitabine-containing conditioning regimen for allo-HSCT reduced relapse and was safe and feasible in treating AML/MDS.


Assuntos
Síndrome de Bronquiolite Obliterante , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Síndromes Mielodisplásicas , Masculino , Feminino , Humanos , Decitabina , Síndromes Mielodisplásicas/terapia , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/complicações , Intervalo Livre de Doença , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Recidiva , Doença Crônica , Doença Enxerto-Hospedeiro/etiologia , Condicionamento Pré-Transplante/efeitos adversos , Estudos Retrospectivos
18.
Nat Commun ; 14(1): 4782, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37553366

RESUMO

Element isotopes are characterized by distinct atomic masses and nuclear spins, which can significantly influence material properties. Notably, however, isotopes in natural materials are homogenously distributed in space. Here, we propose a method to configure material properties by repositioning isotopes in engineered van der Waals (vdW) isotopic heterostructures. We showcase the properties of hexagonal boron nitride (hBN) isotopic heterostructures in engineering confined photon-lattice waves-hyperbolic phonon polaritons. By varying the composition, stacking order, and thicknesses of h10BN and h11BN building blocks, hyperbolic phonon polaritons can be engineered into a variety of energy-momentum dispersions. These confined and tailored polaritons are promising for various nanophotonic and thermal functionalities. Due to the universality and importance of isotopes, our vdW isotope heterostructuring method can be applied to engineer the properties of a broad range of materials.

19.
Zhonghua Liu Xing Bing Xue Za Zhi ; 44(7): 1119-1125, 2023 Jul 10.
Artigo em Chinês | MEDLINE | ID: mdl-37482716

RESUMO

Objective: To evaluate the immunogenicity and safety of revaccination of 23-valent pneumococcal polysaccharide vaccine (PPV23) in elderly people aged ≥60 years. Methods: The elderly aged ≥60 years with 1 dose of PPV23 vaccination were selected as revaccination group and those without history of pneumococcal vaccine immunization were selected as the first vaccination group. One dose of PPV23 was administered to both groups, and the first blood samples were collected before vaccination while the second blood samples were collected on day 28-40 after vaccination. ELISA was used to detect the concentrations of anti-specific serotype Streptococcus pneumoniae podocyte polysaccharide immunoglobulin G, and the safety of the vaccination was evaluated after 30 days. Results: The geometric mean concentration (GMC) of antibody to 23 serotypes before the vaccination (0.73-13.73 µg/ml) was higher in revaccination group than in the first vaccination group (0.39-7.53 µg/ml), the GMC after the vaccination (1.42-31.65 µg/ml) was higher than that before the vaccination (0.73-13.73 µg/ml) in the revaccination group, and the GMC after the vaccination (1.62-43.76 µg/ml) was higher than that before the vaccination (0.39-7.53 µg/ml) in the first vaccination group; the geometric mean growth multiple in revaccination group (2.16-3.60) was lower than that in the first vaccination group (3.86-16.13); The mean 2-fold antibody growth rate was lower in revaccination group (53.68%, 95%CI: 52.30%-55.06%) than in the first vaccination group (93.16%, 95%CI: 92.18%- 94.15%), all differences were significant (P<0.001). After the vaccination, 13 serotypes of GMC were higher in the first vaccination group than in revaccination group (P<0.001), the differences were not significant for 10 serotypes of GMC (P>0.05). The incidence of local adverse reaction was 19.20% and 13.27% in revaccination group and the first vaccination group, respectively (P=0.174). Conclusions: The antibody level in ≥60 years people who received one dose of PPV23 after a 5-year interval was still higher than that in unvaccinated people. The antibody level decreased after 5 years of the first vaccination, and the antibody level could be rapidly increased by one more dose vaccination, but the overall immune response was lower than that of the first vaccination; revaccination with PPV23 has a good safety.


Assuntos
Anticorpos Antibacterianos , Infecções Pneumocócicas , Idoso , Humanos , Imunização Secundária , Vacinas Pneumocócicas , Vacinação , Streptococcus pneumoniae , Infecções Pneumocócicas/prevenção & controle
20.
Space Sci Rev ; 219(5): 37, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37448777

RESUMO

We review comprehensive observations of electromagnetic ion cyclotron (EMIC) wave-driven energetic electron precipitation using data collected by the energetic electron detector on the Electron Losses and Fields InvestigatioN (ELFIN) mission, two polar-orbiting low-altitude spinning CubeSats, measuring 50-5000 keV electrons with good pitch-angle and energy resolution. EMIC wave-driven precipitation exhibits a distinct signature in energy-spectrograms of the precipitating-to-trapped flux ratio: peaks at >0.5 MeV which are abrupt (bursty) (lasting ∼17 s, or ΔL∼0.56) with significant substructure (occasionally down to sub-second timescale). We attribute the bursty nature of the precipitation to the spatial extent and structuredness of the wave field at the equator. Multiple ELFIN passes over the same MLT sector allow us to study the spatial and temporal evolution of the EMIC wave - electron interaction region. Case studies employing conjugate ground-based or equatorial observations of the EMIC waves reveal that the energy of moderate and strong precipitation at ELFIN approximately agrees with theoretical expectations for cyclotron resonant interactions in a cold plasma. Using multiple years of ELFIN data uniformly distributed in local time, we assemble a statistical database of ∼50 events of strong EMIC wave-driven precipitation. Most reside at L∼5-7 at dusk, while a smaller subset exists at L∼8-12 at post-midnight. The energies of the peak-precipitation ratio and of the half-peak precipitation ratio (our proxy for the minimum resonance energy) exhibit an L-shell dependence in good agreement with theoretical estimates based on prior statistical observations of EMIC wave power spectra. The precipitation ratio's spectral shape for the most intense events has an exponential falloff away from the peak (i.e., on either side of ∼1.45 MeV). It too agrees well with quasi-linear diffusion theory based on prior statistics of wave spectra. It should be noted though that this diffusive treatment likely includes effects from nonlinear resonant interactions (especially at high energies) and nonresonant effects from sharp wave packet edges (at low energies). Sub-MeV electron precipitation observed concurrently with strong EMIC wave-driven >1 MeV precipitation has a spectral shape that is consistent with efficient pitch-angle scattering down to ∼ 200-300 keV by much less intense higher frequency EMIC waves at dusk (where such waves are most frequent). At ∼100 keV, whistler-mode chorus may be implicated in concurrent precipitation. These results confirm the critical role of EMIC waves in driving relativistic electron losses. Nonlinear effects may abound and require further investigation.

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