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1.
Ann Surg ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557705

RESUMO

BACKGROUND AND AIMS: Surgery is pivotal in the management of neuroblastoma (NB), particularly in patients with Image-Defined Risk Factors (IDRFs). The International Neuroblastoma Surgical Report Form (INSRF) was introduced to enhance surgical reporting quality and analyze the defining role of extensive surgery in NB. This study reports our experience with INSRF and explores new criteria for evaluating the extent of surgical resection. METHODS: INSRF was deployed to critically analyze 166 patients with abdominal or pelvic NB who underwent surgery at our department between October 2021 and June 2023. Patient demographics, clinical characteristics, surgical datasets, and postoperative complications were described in detail. Receiver operating characteristic (ROC) curves were used to explore a new method to evaluate the extent of resection. A questionnaire was formulated to obtain attitudes/feedback and commentary from surgical oncologists with INSRF. RESULTS: 166 neuroblastoma patients with a median disease age 36.50 months. This study collated 320 INSRF reports. Among the 166 index cases, 137 were documented by two surgeons, with a concordance rate of 16.78%. Items with high inconsistency were (i) the extent of tumor resection (29.20%), (ii) renal vein involvement (25.55%), (iii) abdominal aorta encasement (16.79%), and (iv) mesenteric infiltration (17.52%). According to INSRF, the extent of resection was complete excision in 86 (51.81%) patients, minimal residual tumor < 5 cm3 in 67 (40.36%) patients, and incomplete excision > 5 cm3 in 13 (7.83%) patients. In ROC curve analysis, the number of vessels encased by tumors > 3 had a high predictive value in determining that a tumor could not be completely resected (AUC 0.916, sensitivity 0.838, specificity 0.826) using INSRF as the gold standard reference. The questionnaires showed that surgeons agreed that the extent of resection and tumor involvement of organ/vascular structures were important, while the definition and intervention(s) of intraoperative complications were less operational and understandable. CONCLUSIONS: INSRF has significant clinical application in neuroblastoma surgery. The extent of resection can be predicted based on the number of tumor-encased blood vessels. Supplementary information should be considered with the INSRF to aid practitioner reporting. Multicenter studies are needed to explore the defining role of INSRF in NB surgical management.

2.
Future Oncol ; 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38445361

RESUMO

Background: The authors' preclinical study has confirmed that RO adjuvant (composed of TLR 7 agonists [imiquimod/R837] and OX40 agonists) injected into local lesions induces the regression of both primary tumor and distant metastasis. The authors propose to realize local control and exert abscopal effect through an 'R-ISV-RO' in situ strategy plus anti-PD-1 monoclonal antibody in advanced tumors. Methods: This study is a single-center, exploratory, phase II trial to evaluate the efficacy and safety of R-ISV-RO plus anti-PD-1 monoclonal antibody in advanced tumors. 30 patients with one or more measurable extracerebral lesions that are accessible for radiation or injection will be enrolled. The primary endpoint is the objective response rate of target lesions. Discussion/Conclusion: The efficacy and safety of the novel strategy will be further validated through this clinical trial.Clinical trial registration: ChiCTR2100053870 (www.chictr.org.cn/).


[Box: see text].

3.
BMC Surg ; 24(1): 168, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811926

RESUMO

BACKGROUND: Lymphatic leakage is one of the postoperative complications of neuroblastoma. The purpose of this study is to summarize the clinical characteristics and risk factors of lymphatic leakage and try to find effective prevention and treatment measures. METHODS: A retrospective study included 186 children with abdominal neuroblastoma, including 32 children of lymphatic leakage and 154 children of non-lymphatic leakage. The clinical information, surgical data, postoperative abdominal drainage, treatment of lymphatic leakage and prognosis of the two groups were collected and analyzed. RESULTS: The incidence of lymphatic leakage in this cohort was 14% (32 children). Through univariate analysis of lymphatic leakage group and non-lymphatic leakage group, we found that lymphatic leakage increased the complications, prolonged the time of abdominal drainage and hospitalization, and delayed postoperative chemotherapy (p < 0.05). In this cohort, the median follow-up time was 46 (95% CI: 44-48) months. The follow-up data of 7 children were partially missing. 147 children survived, of which 23 had tumor recurrence (5 children recurred in the surgical area). 37 children died, of which 32 had tumor recurrence (9 children recurred in the operation area). In univariate analysis, there was no statistical difference in overall survival (p = 0.21) and event-free survival (p = 0.057) between lymphatic leakage group and non-lymphatic leakage group, while 3-year cumulative incidence of local progression was higher in lymphatic leakage group (p = 0.015). However, through multivariate analysis, we found that lymphatic leakage did not affect event-free survival, overall survival and cumulative incidence of local progression in children with neuroblastoma. Resection of 5 or more lymphatic regions was an independent risk factor for lymphatic leakage after neuroblastoma surgery. All 32 children with lymphatic leakage were cured by conservative treatment without surgery. Of these, 75% (24/32) children were cured by fat-free diet or observation, 25% (8/32) children were cured by total parenteral nutrition. The median drain output at diagnosis in total parenteral nutrition group was higher than that in non-total parenteral nutrition group (p < 0.001). The cut-off value was 17.2 ml/kg/day. CONCLUSIONS: Lymphatic leakage does not affect the prognosis of children with neuroblastoma, but long-term drain output caused by lymphatic leakage will still adversely affect postoperative complications and follow-up treatment, which requires attention and active treatment measures. More attention should be paid to the children with 5 or more lymphatic regions resection, and the injured lymphatic vessels should be actively found and ligated after tumor resection to reduce the postoperative lymphatic leakage. Early application of total parenteral nutrition is recommended for those who have drain output at diagnosis of greater than 17.2 ml/kg/day. LEVEL OF EVIDENCE: Level III, Treatment study (Retrospective comparative study).


Assuntos
Laparotomia , Neuroblastoma , Complicações Pós-Operatórias , Humanos , Neuroblastoma/cirurgia , Masculino , Estudos Retrospectivos , Feminino , Fatores de Risco , Pré-Escolar , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Lactente , Laparotomia/métodos , Criança , Neoplasias Abdominais/cirurgia , Prognóstico , Incidência , Drenagem/métodos
4.
Molecules ; 29(11)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38893563

RESUMO

This study introduces a novel organosilicon-modified polysaccharide (Si-AP) synthesized via grafting and comprehensively evaluates its performance in water-based drilling fluids (WBDFs). The molecular structure of Si-AP was characterized using Fourier-transform infrared spectroscopy (FTIR) and 1H-NMR experiments. Thermalgravimetric analysis (TGA) confirmed the good thermal stability of Si-AP up to 235 °C. Si-AP significantly improves the rheological properties and fluid loss performance of WBDFs. With increasing Si-AP concentration, system viscosity increases, API filtration rate decreases, clay expansion is inhibited, and drilling cuttings hydration dispersion is suppressed, especially under high-temperature conditions. Additionally, mechanistic analysis indicates that the introduction of siloxane groups can effectively inhibit the thermal degradation of AP chains and enhance their high-temperature resistance. Si-AP can form a lubricating film by adsorbing on the surface of clay particles, improving mud cake quality, reducing the friction coefficient, and significantly enhancing the lubricating performance of WBDFs. Overall, Si-AP exhibits a higher temperature-resistance limit compared to AP and more effectively optimizes the lubrication, inhibition, and control of the filtration rate of WBDFs under high-temperature conditions. While meeting the requirements of drilling fluid systems under high temperatures, Si-AP also addresses environmental concerns and holds promise as an efficient solution for the exploitation of deep-seated oil and gas resources.

5.
World J Surg Oncol ; 21(1): 113, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36978162

RESUMO

OBJECTIVE: To explore the criteria, safety and efficacy of laparoscopic surgery in pediatric neuroblastoma (NB). METHODS: A retrospective study of 87 patients with NB without image-defined risk factors (IDRFs) between December 2016 and January 2021 at Beijing Children's Hospital was conducted. Patients were divided into two groups according to the surgical procedure. RESULTS: Between the 87 patients, there were 54 (62.07%) cases in the open surgery group and 33 (37.93%) cases in the laparoscopic surgery group. There were no significant differences between the two groups regarding demographic characteristics, genomic and biological features, operating time or postoperative complications. However, in terms of intraoperative bleeding (p = 0.013) and the time to start postoperative feeding after surgery (p = 0.002), the laparoscopic group was obviously better than the open group. Furthermore, there was no significant difference in the prognosis between the two groups, and no recurrence or death was observed. CONCLUSION: For children with localized NB who have no IDRFs, laparoscopic surgery could be performed safely and effectively. Surgeons who are skilled in this can help children reduce surgical injuries, speed up postoperative recovery, and obtain the same prognosis as open surgery.


Assuntos
Laparoscopia , Neuroblastoma , Criança , Humanos , Estudos Retrospectivos , Estudos de Viabilidade , Neuroblastoma/cirurgia , Fatores de Risco , Laparoscopia/efeitos adversos , Resultado do Tratamento
6.
Pediatr Surg Int ; 39(1): 76, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36622431

RESUMO

OBJECTIVE: Hepatoblastoma (HB) tumor rupture is a high-risk criterion in the International Childhood Liver Tumors Strategy Group (SIOPEL) 3/4 protocol. However, the causes and risk factors for HB rupture are still unknown, and whether tumor rupture is an independent risk factor for HB prognosis is still controversial. The purpose of this study was to retrospectively analyze the clinical characteristics of children with HB tumor rupture and to search for clinical risk factors to conduct early prediction and intervention. METHODS: We conducted a retrospective study of 27 patients with HB rupture between July 2009 and July 2019. To further identify the risk factors for HB rupture, we included 97 nonruptured HB patients from January 2013 to January 2019. We searched for potentially useful characteristics for HB rupture by univariate and multivariate logistic regression analyses. RESULTS: There were 27 patients with HB rupture, with the median age of 31 (12, 69) months. Nineteen cases (70.37%) were spontaneous tumor rupture, 1 case (3.70%) was posttraumatic rupture, 2 cases (7.41%) were tumor rupture after the biopsy, and 5 cases (18.52%) were tumor rupture after chemotherapy. After the tumor rupture, 4 patients died of hemorrhagic shock and multiple organ dysfunction syndrome (MODS), 4 patients refused further therapy and were discharged against medical advice, and the remaining 19 patients were stable after emergency treatment. After the treatment, 14 patients survived without disease, 2 patients died, and 3 patients were lost to follow-up. The median follow-up was 48 (33, 60) months, the 3-year overall survival (OS) was 54.7%. Compared with the non-tumor rupture group by multivariate logistic regression analysis, it was found that the maximum diameter of the primary tumor > 13.4 cm, and vascular invasion were independent risk factors for tumor rupture. CONCLUSION: HB rupture is rare, but it seriously threatens the life and health of children. In the acute phase of tumor rupture, surgery, rescue chemotherapy, transcatheter arterial embolization (TAE) and other supportive care can be adopted. Large tumors and vascular invasion are risk factors for HB rupture. LEVEL OF EVIDENCE: Level IV.


Assuntos
Hepatoblastoma , Neoplasias Hepáticas , Humanos , Criança , Lactente , Pré-Escolar , Hepatoblastoma/terapia , Hepatoblastoma/tratamento farmacológico , Estudos Retrospectivos , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/tratamento farmacológico , Prognóstico , Fatores de Risco , China/epidemiologia
7.
J Anim Physiol Anim Nutr (Berl) ; 107(1): 165-172, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34726311

RESUMO

This study investigates the use of nanofiber microcapsules produced by electrostatic spinning as a carrier for the delivery of lactic acid bacteria (LAB) to the intestine of ruminants. We hypothesized that the LAB encapsulated into nanofiber microcapsules can be delivered to a ruminant's intestinal tract with little effect on the rumen fermentation and related bacteria. The in vitro experiment included three treatments: control group; 0.01g Lactobacillus acidophilus NCFM (L. acidophilus NCFM) encapsulated in nanofiber microcapsules by electrostatic spinning group (ELAN, 2.0 × 1011  CFU/g); and 0.01g L. acidophilus NCFM powder group (LANP, 2.0 × 1011  CFU/g), each incubated with 30 ml of buffer rumen fluid for 48h to determine the effect on rumen fermentation, then the abundance of L. acidophilus NCFM in the intestine was estimated using the modified in vitro three-step procedure. Treatment responses were statistically analysed using one-way ANOVA. The results showed that compared to the control, the ELAN group had a significant increase in pH (p < 0.05), while the LANP group had a non-significant decrease in pH (p > 0.05). LANP and ELAN groups had no significant influence on total volatile fatty acid and individual volatile fatty acids (p > 0.05), apart from isobutyric acid of both groups, which reduced (p < 0.05). ELAN group had a decreasing trend of gas production and dry matter digestion, while the LANP group increased them significantly (p < 0.05). During the 16h and 48h rumen incubation, compared with control, there was no significant change in all bacteria in the ELAN group (p > 0.05), while the LANP group increased the relative abundance levels of S. bovis, S. ruminantium, M. elsdenii, F. succinogenes, B. fibrisolvens, Lactobacillus, L. acidophilus NCFM (p < 0.05). In the intestinal part, compared with control, the relative abundance of L. acidophilus NCFM in the ELAN group increased significantly (p < 0.05), while the result was not observed in the LANP group. We concluded based on our findings that L. acidophilus NCFM could be protected by nanofiber microcapsules and delivered to the intestinal site with little influence on the rumen fermentation and bacterial community, suggesting nanofiber microcapsules prepared by electrospinning technology could be used as a carrier for rumen-protected study.


Assuntos
Lactobacillales , Nanofibras , Animais , Cápsulas/metabolismo , Intestinos , Lactobacillus acidophilus/fisiologia , Ácidos Graxos Voláteis/metabolismo , Ruminantes , Rúmen/metabolismo , Fermentação
8.
Glob Chang Biol ; 27(20): 5198-5210, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34228871

RESUMO

Changes in ecological processes over time in ambient treatments are often larger than the responses to manipulative treatments in climate change experiments. However, the impacts of human-driven environmental changes on the stability of natural grasslands have been typically assessed by comparing differences between manipulative plots and reference plots. Little is known about whether or how ambient climate regulates the effects of manipulative treatments and their underlying mechanisms. We collected two datasets, one a 36-year long-term observational dataset from 1983 to 2018, and the other a 10-year manipulative asymmetric warming and grazing experiment using infrared heaters with moderate grazing from 2006 to 2015 in an alpine meadow on the Tibetan Plateau. The 36-year observational dataset shows that there was a nonlinear response of community stability to ambient temperature with a positive relationship between them due to an increase in ambient temperature in the first 25 years and then a decrease in ambient temperature thereafter. Warming and grazing decreased community stability with experiment duration through an increase in legume cover and a decrease in species asynchrony, which was due to the decreasing background temperature through time during the 10-year experiment period. Moreover, the temperature sensitivity of community stability was higher under the ambient treatment than under the manipulative treatments. Therefore, our results suggested that ambient climate may control the directional trend of community stability while manipulative treatments may determine the temperature sensitivity of the response of community stability to climate relative to the ambient treatment. Our study emphasizes the importance of the context dependency of the response of community stability to human-driven environmental changes.


Assuntos
Mudança Climática , Pradaria , Herbivoria , Temperatura
9.
Med Sci Monit ; 27: e930785, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34465716

RESUMO

BACKGROUND Implant placement in the posterior maxilla is typically complicated by a shortage of bone. Gelatin sponge could be combined with an appropriate material to enhance mechanical strength and maintain stability of an implant. This study aimed to evaluate the clinical application of bone grafting with bovine bone mixed with gelatin sponge. MATERIAL AND METHODS Fifty-four patients were divided into a control group (deproteinized bovine bone, n=26) and a test group (deproteinized bovine bone combined with gelatin sponge, n=28). Implants were placed in patients simultaneously after surgery (operation). Cone-beam computed tomography examination was carried out immediately and 6 months after surgery. Space with grafting materials was measured with Mimics software (version 16.0). RESULTS No remarkable differences were found for simultaneous placement, height of residual bone, delayed placement, width of residual bone, graft volume immediately after surgery (V1), graft volume 6 months after surgery (V2), or volumetric change rate between the test group and the control group (P>0.05). Graft volume V2 was remarkably decreased compared with V1 in the control and test groups (P=0.01). There were no significant differences for bone height immediately after surgery (H1) and bone height at 6 months after surgery (H2) between the 2 groups. Bone height H2 was markedly decreased compared with H1 (P<0.05). At 1 year after implantation, there was 1 implant loss in the control group and 2 in the test group. The implant survival rate in the control group was 97.62% and 95.24% in the test group. CONCLUSIONS Absorbable gelatin sponge combined with bovine bone particles was an effective and economical material for use in routine sinus floor elevation surgery.


Assuntos
Implantes Absorvíveis , Substitutos Ósseos , Esponja de Gelatina Absorvível/uso terapêutico , Teste de Materiais , Maxila/cirurgia , Levantamento do Assoalho do Seio Maxilar/instrumentação , Transplante Ósseo , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto
10.
Curr Oncol Rep ; 22(8): 76, 2020 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-32596779

RESUMO

PURPOSE OF REVIEW: Immunotherapy shows great promises in solid tumors. Locoregional therapy can promote systemic immune response in hepatocellular carcinoma (HCC). The combination of locoregional therapy and immune checkpoint inhibitors (ICIs) activates a synergistic effect that can enhance the potency of anti-tumor immunity. This review aims to summarize the underlying mechanisms of locoregional therapy combined with ICIs and their applications in clinical settings. RECENT FINDINGS: The characteristics of high invasiveness and refractoriness of HCC are what limit the outcomes of treatments. Sorafenib provides an additional treatment option for extrahepatic spread and vascular invasion, making long-term survival possible for patients with advanced HCC to some degree. However, its shortcomings of low response rate and high toxicity result in limited applications in clinical practice. Immunotherapy is a promising emerging therapy with great prospect in HCC, but the self-tolerance of HCC constrains the effectiveness of ICIs. Consequently, the efficacy of single immunotherapy is unsatisfactory. Locoregional therapy can not only destroy primary tumors but also stimulate the release of neoplasm antigens to increase the efficiency of immune response in HCC. Locoregional therapy combined with ICIs may have an amplification effect on immune response. Locoregional therapy plays a vital role in stimulating anti-tumor immune response. The combination of locoregional therapy and ICIs has a synergistic effect on anti-tumor immunity.


Assuntos
Carcinoma Hepatocelular/terapia , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Hepáticas/terapia , Animais , Braquiterapia , Carcinoma Hepatocelular/imunologia , Quimioembolização Terapêutica , Terapia Combinada , Humanos , Neoplasias Hepáticas/imunologia , Ablação por Radiofrequência , Sorafenibe/uso terapêutico
11.
HPB (Oxford) ; 22(2): 306-311, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31409540

RESUMO

BACKGROUND: To investigate the safety, feasibility, and complications of using duodenum-preserving pancreas head resection (DPPHR) to treat pediatric benign and low-grade malignant pancreatic head tumors. METHODS: Patients with pancreatic head tumors that underwent resection were retrospectively analyzed for perioperative factors and postoperative complications. RESULTS: Thirty-five patients with a median age of 10 years at diagnosis were identified. Patients were divided by procedures into the DPPHR (n = 22), local enucleation (n = 7) and pylorus-preserving pancreatoduodenectomy (PPPD, n = 6) groups. No significant difference was found in operation time between the DPPHR and PPPD groups (P > 0.05). Significantly, longer drainage time, duration of somatostatin use and hospital stay were observed in the DPPHR group than in the PPPD group (P < 0.05). The incidences of short-term complications were not significantly different among the three groups (P > 0.05). The incidence of long-term complications was markedly lower in both the DPPHR and local enucleation groups than in the PPPD group (P < 0.05). CONCLUSION: DPPHR might be a safe treatment option for pediatric patients with benign and low-grade malignant pancreatic head tumors. The incidence of long-term complications was significantly lower with DPPHR. However, perioperative management might be challenging for surgeons.


Assuntos
Pancreatectomia , Neoplasias Pancreáticas/cirurgia , Complicações Pós-Operatórias/epidemiologia , Fatores Etários , Criança , Duodeno , Estudos de Viabilidade , Feminino , Humanos , Incidência , Masculino , Tratamentos com Preservação do Órgão , Neoplasias Pancreáticas/patologia , Pancreaticoduodenectomia , Piloro , Estudos Retrospectivos , Resultado do Tratamento
12.
Pediatr Res ; 85(6): 885-894, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30718793

RESUMO

BACKGROUND: Opsoclonus-myoclonus syndrome (OMS) is a rare neurological disorder, usually accompanied by neuroblastoma (NB). There is no targeted treatment and animal model of OMS. We aimed to investigate whether insulin-like growth factor 1 (IGF-1)/phosphoinositide 3-kinase (PI3K) signaling alleviates neuronal cytolysis in pediatric OMS. METHODS: Cultured rat cerebral cortical neurons and cerebellar neurons were incubated with sera or IgG isolated from sera of children with OMS and NB. Cytolysis and PI3K expression were measured by the lactate dehydrogenase assay and enzyme-linked immunosorbent assay, respectively. Using inhibitors and activators, the effects of IGF-1 and PI3K on cytolysis were investigated. RESULTS: The incubation of sera or IgG from children with OMS and NB increased cytolysis in not only cerebellar neurons, but also cerebral cortical neurons. Furthermore, the IGF-1 receptor antagonist NVP-AEW541 exaggerated cytolysis in children with OMS and NB. IGF-1 alleviated cytolysis, which was blocked by the PI3K inhibitor LY294002. Additionally, sera or IgG from children with OMS and NB compensatively elevated PI3K expression. LY294002 exacerbated cytolysis; whereas, the PI3K activator 740 Y-P suppressed cytolysis. CONCLUSION: IGF-1/PI3K signaling alleviates the cytolysis of cultured neurons induced by serum IgG from children with OMS and NB, which may be innovation therapy targets.


Assuntos
Fator de Crescimento Insulin-Like I/farmacologia , Neuroblastoma/tratamento farmacológico , Neuroblastoma/metabolismo , Síndrome de Opsoclonia-Mioclonia/tratamento farmacológico , Síndrome de Opsoclonia-Mioclonia/metabolismo , Animais , Células Cultivadas , Pré-Escolar , Cromonas/farmacologia , Feminino , Humanos , Imunoglobulina G/administração & dosagem , Imunoglobulina G/sangue , Masculino , Morfolinas/farmacologia , Neuroblastoma/complicações , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Síndrome de Opsoclonia-Mioclonia/complicações , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Ratos , Receptor IGF Tipo 1/antagonistas & inibidores , Transdução de Sinais
13.
Implant Dent ; 27(5): 555-563, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30134266

RESUMO

PURPOSE: To investigate the effect(s) of screw-access hole (SAH) in different diameters on the cement-retained implant prosthodontic systems and surrounding cortical bones. MATERIALS AND METHODS: Twenty finite element models were divided into 4 groups: 2 types of full-contour (FC) crowns (Y-TZP, gold alloy) and 2 types of porcelain-fused-to-metal crowns (based on Co-Cr, Au-Pd alloy). For each group, 5 crowns were simulated by varying the diameter of SAH (0, 1, 2, 3, and 4 mm). A vertical load of 200 N and an oblique load of 100 N (45°s) were applied. All models were analyzed with finite element analysis software. RESULTS: The stress on the occlusal surface of crowns was almost unchanged when the SAH was within 0 to 3 mm, whereas it showed an obvious increase when it reached 4 mm. The stress concentration was also suddenly changed from the loading area to the hole margin under vertical loading. As for the screw, a lower stress level was observed in vertical loading when an FC crown with an SAH within 0 to 1 mm was applied. The stress concentration was constantly located at the beginning of the first thread. Stresses of other components remained almost unchanged. CONCLUSIONS: From the aspect of biomechanics, an FC crown with a 1-mm access hole is recommended when a combined cement- and screw-retained crown was used in the posterior region.


Assuntos
Coroas , Cimentos Dentários/uso terapêutico , Projeto do Implante Dentário-Pivô , Implantes Dentários , Prótese Dentária Fixada por Implante , Adulto , Fenômenos Biomecânicos , Osso Cortical/patologia , Análise do Estresse Dentário , Análise de Elementos Finitos , Humanos , Masculino , Mandíbula/patologia
15.
J Environ Manage ; 173: 121-6, 2016 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26985730

RESUMO

The effects of climate change and human activities on grassland degradation and soil carbon stocks have become a focus of both research and policy. However, lack of research on appropriate sampling design prevents accurate assessment of soil carbon stocks and stock changes at community and regional scales. Here, we conducted an intensive survey with 1196 sampling sites over an area of 190 km(2) of degraded alpine meadow. Compared to lightly degraded meadow, soil organic carbon (SOC) stocks in moderately, heavily and extremely degraded meadow were reduced by 11.0%, 13.5% and 17.9%, respectively. Our field survey sampling design was overly intensive to estimate SOC status with a tolerable uncertainty of 10%. Power analysis showed that the optimal sampling density to achieve the desired accuracy would be 2, 3, 5 and 7 sites per 10 km(2) for lightly, moderately, heavily and extremely degraded meadows, respectively. If a subsequent paired sampling design with the optimum sample size were performed, assuming stock change rates predicted by experimental and modeling results, we estimate that about 5-10 years would be necessary to detect expected trends in SOC in the top 20 cm soil layer. Our results highlight the utility of conducting preliminary surveys to estimate the appropriate sampling density and avoid wasting resources due to over-sampling, and to estimate the sampling interval required to detect an expected sequestration rate. Future studies will be needed to evaluate spatial and temporal patterns of SOC variability.


Assuntos
Carbono/análise , Monitoramento Ambiental/métodos , Pradaria , Solo/química , Biodegradação Ambiental , Biomassa , Sequestro de Carbono , Plantas , Tamanho da Amostra , Tibet
16.
J Urol ; 194(4): 897-902, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25813450

RESUMO

PURPOSE: We assessed the association between the R.E.N.A.L., PADUA and centrality index scores and perioperative outcomes, and determined the efficacy of each scoring system over the simple parameter of tumor size. MATERIALS AND METHODS: We conducted a retrospective review of the records of patients who underwent laparoscopic radio frequency ablation of renal tumors from February 2006 to April 2014 at our institution. Tumors were categorized using the R.E.N.A.L., PADUA and centrality index score, which were determined by analyzing preoperative imaging. The relationships between each variable and change in glomerular filtration rate, estimated blood loss, operative time and postoperative complications were examined. RESULTS: Laparoscopic radio frequency ablation was performed in 215 selected patients with preoperative imaging available. The interclass correlations coefficient of the 3 observers was 0.87, 0.84 and 0.82 for the C-Index, the R.E.N.A.L. and the PADUA scoring system, respectively. R.E.N.A.L. score, PADUA score and PADUA complexity were significantly associated with postoperative complications (p=0.040, 0.015 and 0.006, respectively). However, major complications were only associated with high PADUA complexity (chi-square 23.851, p <0.05). Each scoring system had a significant association with operative time and estimated blood loss (p <0.05), except that the C-index score had no relationship with estimated blood loss (p=0.083). The accuracy of each scoring system in predicting perioperative outcomes and postoperative complications was superior to that of tumor size. CONCLUSIONS: Each scoring system has an advantage over tumor size in describing tumor complexity and may help with surgical decision making. Further studies are required to validate their efficacy in evaluating the intraoperative and postoperative results after renal laparoscopic radio frequency ablation.


Assuntos
Ablação por Cateter , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Laparoscopia , Feminino , Humanos , Neoplasias Renais/classificação , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Carga Tumoral
17.
J Urol ; 193(2): 430-5, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25106899

RESUMO

PURPOSE: We compared outcomes in patients treated with radio frequency ablation or partial nephrectomy for clinical cT1b renal cell carcinoma. MATERIALS AND METHODS: We retrospectively reviewed the records of all patients who underwent radio frequency ablation or nephrectomy between February 2006 and December 2010. Radiographic followup with contrast imaging was performed 7 days, 3 and 6 months, and every 6 months thereafter after radio frequency ablation sequentially. The followup protocol for partial nephrectomy was every 6 months in the initial 3 years and annually thereafter. The Kaplan-Meier method was used to generate survival curves, which were compared with the log rank test. Multivariable regression analysis was done to determine predictors of survival. RESULTS: A total of 56 patients who met selection criteria were included in study. Patients in the radio frequency ablation group had relatively higher mean age and a higher mean ASA® score than those in the partial nephrectomy group. Mean tumor diameter was significantly larger in the partial nephrectomy cohort. For radio frequency ablation vs partial nephrectomy 5-year overall, cancer specific and disease-free survival was 85.5% (95% CI 72.2-98.8) vs 96.6% (95% CI 95.9-97.3), 92.6% (95% CI 82.4-98.1) vs 96.6% (95% CI 95.9-97.3) and 81.0% (95% CI 66.2-95.8) vs 89.7% (95% CI 78.5-97.9), respectively. The percent decrease in the glomerular filtration rate was significantly lower in the radio frequency ablation group at early and last followup. CONCLUSIONS: In appropriately selected patients with stage cT1b renal cell carcinoma radio frequency ablation is an effective treatment option that provides 5-year overall, cancer specific and disease-free survival comparable to that of partial nephrectomy as well as better renal function preservation than partial nephrectomy.


Assuntos
Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/cirurgia , Ablação por Cateter , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Nefrectomia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
18.
Int J Surg Case Rep ; 114: 109158, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38100930

RESUMO

INTRODUCTION: Desmoplastic small round cell tumor (DSRCT) is a rare sarcoma predominantly afflicting young males. CASE PRESENTATION: In this current report, a two-year-old boy was admitted to the hospital for the evaluation of a left chest wall mass. Imaging revealed the tumor's presence in the left chest, compressing lung tissue. Subsequently, histological analysis confirmed the DSRCT diagnosis following a biopsy. The patient underwent a comprehensive management strategy centered around surgery, successfully completing the entire treatment course without experiencing relapse during subsequent follow-up assessments. DISCUSSION: When chest wall tumors are inoperable upon initial diagnosis, a biopsy is essential to clarify the pathology and assist in the diagnostic process. If a patient is diagnosed with DRSCT and conventional chemotherapy fails with surgical resection still not feasible, timely adjustment of the chemotherapy regimen coupled with targeted drug administration can reduce the tumor, enable complete resection, and improve the overall prognosis. CONCLUSION: DSRCT is a rare malignancy associated with a generally poor prognosis. The administration of a combined treatment approach involving oral targeted medication (anlotinib), chemotherapy, radiotherapy, and aggressive surgical resection holds the potential to enhance the prognosis for pediatric patients with this condition.

19.
Int J Surg Case Rep ; 116: 109358, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38364752

RESUMO

INTRODUCTION AND IMPORTANCE: Congenital hepatoblastoma is an exceedingly rare neoplasm, predominantly documented as isolated instances, with contentious aspects surrounding its therapeutic approaches and prognostic implications. This study aims to comprehensively summarize and evaluate the management experience of congenital hepatoblastoma (CHB). CASE PRESENTATION: This cohort comprised five infants diagnosed with hepatoblastoma, confirmed through pathological examination, and with an onset of symptoms before 28 days of age. They were enrolled between November 2019 and May 2022. The treatment course they underwent has been summarized, and their prognosis has been subject to analysis. CLINICAL DISCUSSION: Distinguishing congenital hepatoblastoma from other medical conditions is typically necessary. Given the patient's tender age, the approach to treatment demands comprehensive assessment, particularly in cases involving unique tumor locations or substantial tumor sizes. The selection of treatment modalities, encompassing preoperative neoadjuvant chemotherapy and surgical techniques, becomes of paramount importance. Furthermore, determining the treatment's endpoint poses a notable challenge and often necessitates a comprehensive evaluation. CONCLUSION: For pediatric patients afflicted with CHB, the application of preoperative neoadjuvant chemotherapy mitigates surgical risks, while the incorporation of surgical procedures followed by postoperative chemotherapy significantly enhances the overall prognosis. Additionally, AFP-L3% levels may serve as a valuable adjunctive marker signifying the conclusion of treatment.

20.
Head Face Med ; 20(1): 30, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745297

RESUMO

BACKGROUND: Computer-guided implant surgery has improved the quality of implant treatment by facilitating the placement of implants in a more accurate manner. This study aimed to assess the accuracy of implant placement in a clinical setting using three techniques: dynamic navigation, static surgical guides, and freehand placement. We also investigated potential factors influencing accuracy to provide a comprehensive evaluation of each technique's advantages and disadvantages. MATERIALS AND METHODS: Ninety-four implants in 65 patients were included in this prospective study. Patients were randomly assigned to one of three groups: dynamic navigation, static surgical guides, or freehand placement. Implants were placed using a prosthetically oriented digital implant planning approach, and postoperative CBCT scans were superimposed on preoperative plans to measure accuracy. Seven deviation values were calculated, including angular, platform, and apical deviations. Demographic and consistency analyses were performed, along with one-way ANOVA and post-hoc tests for deviation values. RESULTS: The mean global platform, global apical, and angular deviations were 0.99 mm (SD 0.52), 1.14 mm (SD 0.56), and 3.66° (SD 1.64°) for the dynamic navigation group; 0.92 mm (SD 0.36), 1.06 mm (SD 0.47), and 2.52° (SD 1.18°) for the surgical guide group; and 1.36 mm (SD 0.62), 1.73 mm (SD 0.66), and 5.82° (SD 2.79°) for the freehand group. Both the dynamic navigation and surgical guide groups exhibited statistically significant differences in all values except depth deviations compared to the freehand group (p < 0.05), whereas only the angular deviation showed a significant difference between the dynamic navigation and surgical guide groups (p = 0.002). CONCLUSION: Our findings highlight the superior accuracy and consistency of dynamic navigation and static surgical guides compared to freehand placement in implant surgery. Dynamic navigation offers precision and flexibility. However, it comes with cost and convenience considerations. Future research should focus on improving its practicality. TRIAL REGISTRATION: This study was retrospectively registered at the Thai Clinical Trials Register-Medical Research Foundation of Thailand (MRF) with the TCTR identification number TCTR20230804001 on 04/08/2023. It was also conducted in accordance with the Declaration of Helsinki and approved by the institutional ethics committee at the Xian Jiaotong University Hospital of Stomatology, Xian, China (xjkqII[2021] No: 043). Written informed consent was obtained from all participants.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Implantação Dentária Endóssea , Cirurgia Assistida por Computador , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada de Feixe Cônico/métodos , Implantação Dentária Endóssea/métodos , Estudos Prospectivos , Cirurgia Assistida por Computador/métodos
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