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1.
Opt Express ; 32(8): 13733-13745, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38859335

RESUMO

The development of effective and safe agricultural treatments requires sub-cellular insight of the biochemical effects of treatments in living tissue in real-time. Industry-standard mass spectroscopic imaging lacks real-time in vivo capability. As an alternative, multiphoton fluorescence lifetime imaging microscopy (MPM-FLIM) allows for 3D sub-cellular quantitative metabolic imaging but is often limited to low frame rates. To resolve relatively fast effects (e.g., photosynthesis inhibiting treatments), high-frame-rate MPM-FLIM is needed. In this paper, we demonstrate and evaluate a high-speed MPM-FLIM system, "Instant FLIM", as a time-resolved 3D sub-cellular molecular imaging system in highly scattering, living plant tissues. We demonstrate simultaneous imaging of cellular autofluorescence and crystalline agrochemical crystals within plant tissues. We further quantitatively investigate the herbicidal effects of two classes of agricultural herbicide treatments, photosystem II inhibiting herbicide (Basagran) and auxin-based herbicide (Arylex), and successfully demonstrate the capability of the MPM-FLIM system to measure biological changes over a short time with enhanced imaging speed. Results indicate that high-frame-rate 3D MPM-FLIM achieves the required fluorescence lifetime resolution, temporal resolution, and spatial resolution to be a useful tool in basic plant cellular biology research and agricultural treatment development.


Assuntos
Herbicidas , Microscopia de Fluorescência por Excitação Multifotônica , Herbicidas/farmacologia , Microscopia de Fluorescência por Excitação Multifotônica/métodos , Imageamento Tridimensional/métodos , Agricultura
2.
Pediatr Blood Cancer ; 71(2): e30796, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38054692

RESUMO

The International Society of Paediatric Oncology (SIOP) launched a program to map all pediatric cancer facilities around the world. After the results in Africa were completed, the strategy for data collection for Latin America was revised to improve the accuracy and avoid duplications. In partnership with SIOP, the Sociedad Latino Americana de Oncología Pediátrica (SLAOP) approached their delegates who provided the contacts for a 10-question survey about their institutional capacities. Data were collected by email, online meetings, or telephone calls, and stored in a secure platform. All but one country participated and a high number of centers were recorded.


Assuntos
Neoplasias , Criança , Humanos , América Latina , Neoplasias/terapia , Oncologia , Inquéritos e Questionários , África
3.
J Pediatr Hematol Oncol ; 46(1): e107-e110, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37916829

RESUMO

Methotrexate is a major component of pediatric leukemia treatment. While toxicities are common after high-dose methotrexate, escalating dose methotrexate (Capizzi methotrexate) is typically well-tolerated. We report an adolescent Hispanic female with pre-B acute lymphoblastic leukemia, preexisting obesity and hepatic steatosis who developed severe multiorgan failure following an escalating dose of methotrexate with delayed methotrexate excretion of 11 days. We identified one similar report in an obese adult; however, this case is the first to our knowledge involving a pediatric patient. With the rising incidence of obesity and associated comorbidities among children and adolescents with leukemia, attention to potential risks for this population is warranted.


Assuntos
Obesidade Infantil , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Adulto , Criança , Humanos , Adolescente , Feminino , Metotrexato/efeitos adversos , Obesidade Infantil/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
4.
Pediatr Hematol Oncol ; 41(2): 135-149, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37865916

RESUMO

High-dose methotrexate (HDMTX) is used to treat a broad spectrum of cancers. Methotrexate (MTX) monitoring and adequate supportive care are critical for safe drug administration; however, MTX level timing is not always possible in low- and middle-income countries. The aim of this study was to evaluate HDMTX supportive care capacity and MTX monitoring practices in Latin America (LATAM) to identify gaps and opportunities for improvement. A multicenter survey was conducted among LATAM pediatric oncologists. Twenty healthcare providers from 20 institutions answered the online questionnaire. HDMTX was used to treat acute lymphoblastic leukemia (ALL; 100%), non-Hodgkin lymphoma (84.2%), diffuse large B-cell lymphoma (47.4%), osteosarcoma (78.9%), and medulloblastoma (31.6%). Delays in starting HDMTX infusion were related to bed shortages (47.4%) and MTX shortages (21.1%). MTX monitoring was performed at an in-hospital laboratory in 52%, at an external/nearby laboratory in 31.6%, and was not available in 10.5%. Median interval between sampling and obtaining MTX levels was ≤ 2 h in 45% and ≥ 6 h in 30%, related to laboratory location. Sites without access to MTX monitoring reduced the MTX dose for patients with high-risk ALL or did not include MTX in the treatment of patients with osteosarcoma. Respondents reported that implementation of point-of-care testing of MTX levels is feasible. In LATAM, highly variable supportive care capacity may affect the safe administration of MTX doses. Improving accessibility of MTX monitoring and the speed of obtaining results should be prioritized to allow delivery of full doses of MTX required by the current protocols.


Assuntos
Neoplasias Ósseas , Neoplasias Cerebelares , Osteossarcoma , Criança , Humanos , Metotrexato/uso terapêutico , Antimetabólitos Antineoplásicos/efeitos adversos , América Latina/epidemiologia , Osteossarcoma/tratamento farmacológico , Neoplasias Ósseas/tratamento farmacológico
5.
Front Nephrol ; 3: 1193494, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37790293

RESUMO

Introduction: Early identification of compromised renal clearance caused by high-dose methotrexate (HDMTX) is essential for initiating timely interventions that can reduce acute kidney injury and MTX-induced systemic toxicity. Methods: We induced acute kidney injury (AKI) by infusing 42 juvenile pigs with 4 g/kg (80 g/m2) of MTX over 4 hours without high-volume alkalinizing hydration therapy. Concentrations of serum creatinine and MTX were measured at 15 time points up to 148 hours, with 10 samples collected during the first 24 hours after the start of the HDMTX infusion. Results: During the first 28 hours, 81% of the pigs had increases in the concentrations of serum creatinine in one or more samples indicative of AKI (i.e., > 0.3g/dL increase). A rate of plasma MTX clearance of less than 90% during the initial 4 hours after the HDMTX infusion and a total serum creatinine increase at 6 and 8 hours after starting the infusion greater than 0.3 g/dL were predictive of AKI at 28 hours (p < 0.05 and p < 0.001, respectively). At conclusion of the infusion, pigs with a creatinine concentration more than 0.3 g/dL higher than baseline or serum MTX greater than 5,000 µmol/L had an increased risk of severe AKI. Conclusions: Our findings suggest that serum samples collected at conclusion and shortly after HDMTX infusion can be used to predict impending AKI. The pig model can be used to identify biological, environmental, and iatrogenic risk factors for HDMTX-induced AKI and to evaluate interventions to preserve renal functions, minimize acute kidney injury, and reduce systemic toxicity.

6.
EClinicalMedicine ; 64: 102222, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37811488

RESUMO

In counteracting highly infectious and disruptive respiratory diseases such as COVID-19, vaccination remains the primary and safest way to prevent disease, reduce the severity of illness, and save lives. Unfortunately, vaccination is often not the first intervention deployed for a new pandemic, as it takes time to develop and test vaccines, and confirmation of safety requires a period of observation after vaccination to detect potential late-onset vaccine-associated adverse events. In the meantime, nonpharmacologic public health interventions such as mask-wearing and social distancing can provide some degree of protection. As climate change, with its environmental impacts on pathogen evolution and international mobility continue to rise, highly infectious respiratory diseases will likely emerge more frequently and their impact is expected to be substantial. How quickly a safe and efficacious vaccine can be deployed against rising infectious respiratory diseases may be the most important challenge that humanity will face in the near future. While some organizations are engaged in addressing the World Health Organization's "blueprint for priority diseases", the lack of worldwide preparedness, and the uncertainty around universal vaccine availability, remain major concerns. We therefore propose the establishment of an international candidate vaccine pool repository for potential respiratory diseases, supported by multiple stakeholders and countries that contribute facilities, technologies, and other medical and financial resources. The types and categories of candidate vaccines can be determined based on information from previous pandemics and epidemics. Each participant country or region can focus on developing one or a few vaccine types or categories, together covering most if not all possible potential infectious diseases. The safety of these vaccines can be tested using animal models. Information for effective candidates that can be potentially applied to humans will then be shared across all participants. When a new pandemic arises, these pre-selected and tested vaccines can be quickly tested in RCTs for human populations.

7.
Anal Chem ; 95(35): 12993-12997, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37615663

RESUMO

In this study, we use nanopore arrays as a platform for detecting and characterizing individual nanoparticles (NPs) in real time. Dark-field imaging of nanopores with dimensions smaller than the wavelength of light occurs under conditions where trans-illumination is blocked, while the scattered light propagates to the far-field, making it possible to identify nanopores. The intensity of scattering increases dramatically during insertion of AgNPs into empty nanopores, owing to their plasmonic properties. Thus, momentary occupation of a nanopore by a AgNP produces intensity transients that can be analyzed to reveal the following characteristics: (1) NP scattering intensity, which scales with the sixth power of the AgNP radius, shows a normal distribution arising from the heterogeneity in NP size, (2) the nanopore residence time of NPs, which was observed to be stochastic with no permselective effects, and (3) the frequency of AgNP capture events on a 21 × 21 nanopore array, which varies linearly with the concentration of the NPs, agreeing with the frequency calculated from theory. The lower limit of detection (LOD) for NPs was 130 fM, indicating that the measurement can be used in applications in which ultrasensitive detection is required. The results presented here provide valuable insights into the dynamics of NP transport into and out of nanopores and highlight the potential of nanopore arrays as powerful, massively parallel tools for nanoparticle characterization and detection.

8.
Asian Pac J Cancer Prev ; 24(8): 2773-2780, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37642064

RESUMO

PURPOSE: The asparaginase's (ASP) utility for ALL treatment is limited by neutralizing antibodies, which is problematic in countries whose access limited to alternative preparations. ASP antibody levels and activity was measured during remission induction and associated with allergy manifestations. METHODS: E. coli ASP was dosed at 7500 IU/m2. ASP IgG antibody levels were quantified at the beginning and end of induction. ASP activity was measured 24 hours after 1st and 5th dose (standard-risk) or 7th dose (high-risk patients) administration, and within 24 hours in case of allergic reactions. Allergy was monitored by CTCAE version 3. Parametric and non-parametric was performed for data analysis. RESULTS: ASP antibody and activity levels were available in 41/63 consecutive patients. Allergic manifestations occurred in 13/41, with urticaria being the most frequent. There were no significant differences in subject characteristics based on allergic reactions. The 5th dose was the most frequent time of onset. Antibody levels in allergy group at the end of induction did not differ from those at baseline (p<0.05). Using a 24-hour level of 100 mU/mL as a threshold for adequate ASP activity, 6/13 patients with allergy had adequate levels compared to 26/28 patients without (p<0.05). The ASP activity level at the end of induction phase in both groups did not show a significant decrement. CONCLUSION: The E. coli ASP activity with adequate levels were significantly higher in non-allergy group. Its activity level was not accompanied by increment of IgG in allergic group indicates other factors might affect activity levels in allergy group.


Assuntos
Asparaginase , Urticária , Criança , Humanos , Asparaginase/efeitos adversos , Escherichia coli , Indonésia , Anticorpos
9.
Cancer Treat Rev ; 120: 102603, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37579533

RESUMO

INTRODUCTION: Tumor lysis syndrome (TLS), which occurs spontaneously or in response to anticancer treatment, results in the release of intracellular potassium, phosphorus, and nucleic acids into the bloodstream, which results in secondary clinical complications that may be fatal. Prior TLS guidelines do not take into consideration potent novel oncologic agents or contemporary treatment paradigms with increased risk of TLS. Thus, a modified Delphi panel of experts was convened to provide an update for TLS management guidelines based upon a combination of supporting literature and practice consensus. METHODS: A three-round modified Delphi process was implemented. For round 1, nine expert panelists completed a web-based questionnaire developed using published literature. In round 2, panelists were asked to reconsider their answers to questions that did not reach consensus (defined as ≥ 66% agreement among voting panelists). Round 3 was an unblinded, moderated virtual meeting to discuss any remaining questions that did not reach consensus. RESULTS: Detailed recommendations are given for prophylaxis, monitoring, and management of TLS risks and complications, with hydration being a key element of TLS prophylaxis and management. Guidelines for the management of acute effects of TLS and prevention of long-term renal effects include management of hyperkalemia, hypocalcemia, hyperphosphatemia, and hyperuricemia. DISCUSSION: Although the control of uric acid levels is quite effective with currently available agents, panelists emphasize the importance of monitoring and treating other dangerous electrolyte abnormalities such as hyperkalemia and hyperphosphatemia. Guidelines from this modified Delphi panel should aid clinicians in preventing and managing TLS.

10.
IEEE Open J Eng Med Biol ; 4: 85-95, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37228451

RESUMO

An intuitive and generalisable approach to spatial-temporal feature extraction for high-density (HD) functional Near-Infrared Spectroscopy (fNIRS) brain-computer interface (BCI) is proposed, demonstrated here using Frequency-Domain (FD) fNIRS for motor-task classification. Enabled by the HD probe design, layered topographical maps of Oxy/deOxy Haemoglobin changes are used to train a 3D convolutional neural network (CNN), enabling simultaneous extraction of spatial and temporal features. The proposed spatial-temporal CNN is shown to effectively exploit the spatial relationships in HD fNIRS measurements to improve the classification of the functional haemodynamic response, achieving an average F1 score of 0.69 across seven subjects in a mixed subjects training scheme, and improving subject-independent classification as compared to a standard temporal CNN.

11.
J Biomed Opt ; 28(3): 036501, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36925620

RESUMO

Significance: Machine learning (ML) models based on deep convolutional neural networks have been used to significantly increase microscopy resolution, speed [signal-to-noise ratio (SNR)], and data interpretation. The bottleneck in developing effective ML systems is often the need to acquire large datasets to train the neural network. We demonstrate how adding a "dense encoder-decoder" (DenseED) block can be used to effectively train a neural network that produces super-resolution (SR) images from conventional microscopy diffraction-limited (DL) images trained using a small dataset [15 fields of view (FOVs)]. Aim: The ML helps to retrieve SR information from a DL image when trained with a massive training dataset. The aim of this work is to demonstrate a neural network that estimates SR images from DL images using modifications that enable training with a small dataset. Approach: We employ "DenseED" blocks in existing SR ML network architectures. DenseED blocks use a dense layer that concatenates features from the previous convolutional layer to the next convolutional layer. DenseED blocks in fully convolutional networks (FCNs) estimate the SR images when trained with a small training dataset (15 FOVs) of human cells from the Widefield2SIM dataset and in fluorescent-labeled fixed bovine pulmonary artery endothelial cells samples. Results: Conventional ML models without DenseED blocks trained on small datasets fail to accurately estimate SR images while models including the DenseED blocks can. The average peak SNR (PSNR) and resolution improvements achieved by networks containing DenseED blocks are ≈ 3.2 dB and 2 × , respectively. We evaluated various configurations of target image generation methods (e.g., experimentally captured a target and computationally generated target) that are used to train FCNs with and without DenseED blocks and showed that including DenseED blocks in simple FCNs outperforms compared to simple FCNs without DenseED blocks. Conclusions: DenseED blocks in neural networks show accurate extraction of SR images even if the ML model is trained with a small training dataset of 15 FOVs. This approach shows that microscopy applications can use DenseED blocks to train on smaller datasets that are application-specific imaging platforms and there is promise for applying this to other imaging modalities, such as MRI/x-ray, etc.


Assuntos
Células Endoteliais , Microscopia , Animais , Bovinos , Humanos , Microscopia/métodos , Redes Neurais de Computação , Imageamento por Ressonância Magnética/métodos , Aprendizado de Máquina , Processamento de Imagem Assistida por Computador/métodos
12.
Cancers (Basel) ; 15(5)2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36900250

RESUMO

Primary central nervous system lymphoma (PCNSL) is a highly aggressive non-Hodgkin lymphoma that is confined within the CNS. Due to its ability to cross the blood-brain barrier, high-dose methotrexate (HDMTX) is the backbone for induction chemotherapy. This systematic review was conducted to observe outcomes among different HDMTX doses (low, <3 g/m2; intermediate, 3-4.9 g/m2; high, ≥5 g/m2) and regimens used in the treatment of PCNSL. A PubMed search resulted in 26 articles reporting clinical trials using HDMTX for PCNSL, from which 35 treatment cohorts were identified for analysis. The median dose of HDMTX used for induction was 3.5 g/m2 (interquartile range IQR, 3-3.5); the intermediate dose was most frequently used in the studies examined (24 cohorts, 69%). Five cohorts used HDMTX monotherapy, 19 cohorts used HDMTX + polychemotherapy, and 11 cohorts used HDMTX + rituximab ± polychemotherapy. Pooled overall response rate (ORR) estimates for low, intermediate, and high dose HDMTX cohorts were 71%, 76%, and 76%, respectively. Pooled 2-year progression-free survival (PFS) estimates for low, intermediate, and high HDMTX dose cohorts were 50%, 51%, and 55%, respectively. Regimens that included rituximab showed a tendency to have higher ORR and 2-year PFS than those that did not include rituximab. These findings indicate that current protocols utilizing 3-4 g/m2 of HDMTX in combination with rituximab provide therapeutic efficacy in PCNSL.

13.
Br J Clin Pharmacol ; 89(2): 660-671, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35998099

RESUMO

AIMS: High-dose methotrexate (HDMTX) is an essential part of the treatment of several adult and paediatric malignancies. Despite meticulous supportive care during HDMTX administration, severe toxicities, including acute kidney injury (AKI), may occur contributing to patient morbidity. Population pharmacokinetics provide a powerful tool to predict time to clear HDMTX and adjust subsequent doses. We sought to develop and validate pharmacokinetic models for HDMTX in adults with diverse malignancies and to relate systemic exposure with the occurrence of severe toxicity. METHODS: Anonymized, de-identified data were provided from 101 US oncology practices that participate in the Guardian Research Network, a non-profit clinical research consortium. Modelled variables included clinical, laboratory, demographic and pharmacological data. Population pharmacokinetic analysis was performed by means of nonlinear mixed effects modelling using MonolixSuite. RESULTS: A total of 693 HDMTX courses from 243 adults were analysed, of which 62 courses (8.8%) were associated with stage 2/3 acute kidney injury (43 stage 2, 19 stage 3). A three-compartment model adequately fitted the data. Time-dependent serum creatinine, baseline serum albumin and allometrically scaled bodyweight were clinically significant covariates related to methotrexate clearance. External evaluation confirmed a satisfactory predictive performance of the model in adults receiving HDMTX. Dose-normalized methotrexate concentration at 24 and 48 hours correlated with AKI incidence. CONCLUSION: We developed a population pharmacometric model that considers weight, albumin and time-dependent creatinine that can be used to guide supportive care in adult patients with delayed HDMTX elimination.


Assuntos
Injúria Renal Aguda , Neoplasias , Criança , Humanos , Adulto , Metotrexato , Antimetabólitos Antineoplásicos , Neoplasias/tratamento farmacológico , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/epidemiologia , Convulsões/tratamento farmacológico
14.
Cancer ; 129(5): 771-779, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36504077

RESUMO

BACKGROUND: Children with relapsed acute lymphoblastic leukemia (ALL) in low-income and middle-income countries rarely survive. The Pediatric Hematology-Oncology Association of Central America (AHOPCA) developed the AHOPCA-ALL REC 2014 protocol to improve outcomes in resource-constrained settings without access to stem cell transplantation. METHODS: The AHOPCA-ALL REC 2014 protocol was based on a modified frontline induction phase 1A, a consolidation therapy with six modified R-blocks derived from the ALL-Berlin-Frankfurt-Munster REZ 2002 protocol and intermittent maintenance therapy. Children with B-lineage ALL were eligible after a late medullary relapse, an early or late combined relapse, or any extramedullary relapses. Those with T-lineage ALL were eligible after early and late extramedullary relapses, as were those with both B-lineage and T-lineage relapses occurring at least 3 months after therapy abandonment. RESULTS: The study population included 190 patients with T-lineage (n = 3) and B-lineage (n = 187) ALL. Of those with B-lineage ALL, 25 patients had a very early extramedullary relapse, 40 had an early relapse (32 extramedullary and 8 combined), and 125 had a late relapse (34 extramedullary, 19 combined, and 72 medullary). The main cause of treatment failure was second relapse (52.1%). The 3-year event-free survival rate (± standard error) was 25.9% ± 3.5%, and the 3-year overall survival rate was 36.7% ± 3.8%. The 3-year event-free survival rate was 47.2% ± 4.7% for late relapses. The most frequently reported toxicity was grade 3 or 4 infection. Mortality during treatment occurred in 17 patients (8.9%), in most cases because of infectious complications. CONCLUSIONS: Selected children with relapsed ALL in Central America can be cured with second-line regimens even without access to consolidation with stem cell transplantation. Children in low-income and middle-income countries who have lower risk relapses of ALL should be treated with curative intent.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras , Criança , Humanos , Países em Desenvolvimento , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Recidiva , Protocolos de Quimioterapia Combinada Antineoplásica , Pobreza
15.
Front Bioinform ; 3: 1335413, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38187910

RESUMO

Introduction: Although a powerful biological imaging technique, fluorescence lifetime imaging microscopy (FLIM) faces challenges such as a slow acquisition rate, a low signal-to-noise ratio (SNR), and high cost and complexity. To address the fundamental problem of low SNR in FLIM images, we demonstrate how to use pre-trained convolutional neural networks (CNNs) to reduce noise in FLIM measurements. Methods: Our approach uses pre-learned models that have been previously validated on large datasets with different distributions than the training datasets, such as sample structures, noise distributions, and microscopy modalities in fluorescence microscopy, to eliminate the need to train a neural network from scratch or to acquire a large training dataset to denoise FLIM data. In addition, we are using the pre-trained networks in the inference stage, where the computation time is in milliseconds and accuracy is better than traditional denoising methods. To separate different fluorophores in lifetime images, the denoised images are then run through an unsupervised machine learning technique named "K-means clustering". Results and Discussion: The results of the experiments carried out on in vivo mouse kidney tissue, Bovine pulmonary artery endothelial (BPAE) fixed cells that have been fluorescently labeled, and mouse kidney fixed samples that have been fluorescently labeled show that our demonstrated method can effectively remove noise from FLIM images and improve segmentation accuracy. Additionally, the performance of our method on out-of-distribution highly scattering in vivo plant samples shows that it can also improve SNR in challenging imaging conditions. Our proposed method provides a fast and accurate way to segment fluorescence lifetime images captured using any FLIM system. It is especially effective for separating fluorophores in noisy FLIM images, which is common in in vivo imaging where averaging is not applicable. Our approach significantly improves the identification of vital biologically relevant structures in biomedical imaging applications.

16.
Med Sci (Basel) ; 10(3)2022 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-35997335

RESUMO

Adverse reactions during and shortly after infusing asparaginase for the treatment of acute lymphoblastic leukemia can increase in severity with later doses, limiting further use and increasing relapse risk. Although asparaginase is associated with hyperammonemia, the magnitude of the increase in serum ammonia immediately after the infusion and in response to multiple infusions has not been examined. The concurrence of hyperammonemia and infusion reactions was studied using weaned juvenile pigs that received 12 infusions of Erwinia asparaginase (Erwinase; 1250 U/kg) over 28 days, with two 5-day recovery periods without asparaginase after the eighth and eleventh doses. Infusion reactions and prolonged hyperammonemia (>50 µM ammonia 48 h after the infusion) began after the fourth dose and increased with later doses. Dense sampling for 60 min revealed an acute phase of hyperammonemia that peaked within 20 min after starting the first infusion (298 + 62 µM) and lasted less than 1 h, without apparent symptoms. A pronounced acute hyperammonemia after the final infusion (1260 + 250 µM) coincided with severe symptoms and one mortality during the infusion. The previously unrecognized acute phase of hyperammonemia associated with asparaginase infusion coincides with infusion reactions. The juvenile pig is a translational animal model for understanding the causes of acute and chronic hyperammonemia, differentiating from hypersensitivity reactions, and for improving infusion protocols to reduce acute hyperammonemia and to allow the continued use of asparaginase.


Assuntos
Antineoplásicos , Hiperamonemia , Leucemia-Linfoma Linfoblástico de Células Precursoras , Amônia/uso terapêutico , Animais , Antineoplásicos/toxicidade , Asparaginase/efeitos adversos , Hiperamonemia/induzido quimicamente , Hiperamonemia/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/induzido quimicamente , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Suínos
17.
JCO Glob Oncol ; 8: e2200034, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35749676

RESUMO

PURPOSE: Access to essential cancer medicines is a major determinant of childhood cancer outcomes globally. The degree to which pediatric oncologists deem medicines listed on WHO's Model List of Essential Medicines for Children (EMLc) essential is unknown, as is the extent to which such medicines are accessible on the front lines of clinical care. METHODS: An electronic survey developed was distributed through the International Society of Pediatric Oncology mailing list to members from 87 countries. Respondents were asked to select 10 cancer medicines that would provide the greatest benefit to patients in their context; subsequent questions explored medicine availability and cost. Descriptive and bivariate statistics compared access to medicines between low- and lower-middle-income countries (LMICs), upper-middle-income countries (UMICs), and high-income countries (HICs). RESULTS: Among 159 respondents from 44 countries, 43 (27%) were from LMICs, 79 (50%) from UMICs, and 37 (23%) from HICs. The top five medicines were methotrexate (75%), vincristine (74%), doxorubicin (74%), cyclophosphamide (69%), and cytarabine (65%). Of the priority medicines identified, 87% (27 of 31) are represented on the 2021 EMLc and 77% (24 of 31) were common to the lists generated by LMIC, UMIC, and HIC respondents. The proportion of respondents indicating universal availability for each of the top medicines ranged from 9% to 46% for LMIC, 25% to 89% for UMIC, and 67% to 100% for HIC. Risk of catastrophic expenditure was more common in LMIC (8%-20%), compared with UMIC (0%-28%) and HIC (0%). CONCLUSION: Most medicines that oncologists deem essential for childhood cancer treatment are currently included on the EMLc. Barriers remain in access to these medicines, characterized by gaps in availability and risks of catastrophic expenditure for families that are most pronounced in low-income settings but evident across all income contexts.


Assuntos
Medicamentos Essenciais , Neoplasias , Criança , Estudos Transversais , Países em Desenvolvimento , Medicamentos Essenciais/uso terapêutico , Humanos , Oncologia , Neoplasias/tratamento farmacológico
18.
Sci Total Environ ; 832: 154770, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35341873

RESUMO

BACKGROUND: When the COVID-19 case number reaches a maximum in a country, its capacity and management of health system face greatest challenge. METHODS: We performed a cross-sectional study on data of turning points for cases and deaths for the first three waves of COVID-19 in countries with more than 5000 cumulative cases, as reported by Worldometers and WHO Coronavirus (COVID-19) Dashboard. We compared the case fatality rates (CFRs) and time lags (in unit of day) between the turning points of cases and deaths among countries in different development stages and potential influence factors. As of May 10, 2021, 106 out of 222 countries or regions (56%) reported more than 5000 cases. Approximately half of them have experienced all the three waves of COVID-19 disease. The average mortality rate at the disease turning point was 0.038 for the first wave, 0.020 for the second wave, and 0.023 for wave 3. In high-income countries, the mortality rates during the first wave are higher than that of the other income levels. However, the mortality rates during the second and third waves of COVID-19 were much lower than those of the first wave, with a significant reduction from 5.7% to 1.7% approximately 70%. At the same time, high-income countries exhibited a 2-fold increase in time lags during the second and the third waves compared to the first wave, suggesting that the periods between the cases and deaths turning point extended. High rates in the first wave in developed countries are associated to multiple factors including transportation, population density, and aging populations. In upper middle- and lower middle-income countries, the decreasing of mortality rates in the second and third waves were subtle or even reversed, with increased mortality during the following waves. In the upper and lower middle-income countries, the time lags were about 50% of the durations observed from high-income countries. INTERPRETATION: Economy and medical resources affect the efficiency of COVID-19 mitigation and the clinical outcomes of the patients. The situation is likely to become even worse in the light of these countries' limited ability to combat COVID-19 and prevent severe outcomes or deaths as the new variant transmission becomes dominant.


Assuntos
COVID-19 , Estudos Transversais , Humanos , Renda , Densidade Demográfica , SARS-CoV-2
19.
Pediatr Blood Cancer ; 69(4): e29568, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35084087

RESUMO

BACKGROUND: Tumor boards are part of standard care of patients with complex cancers, but appropriate multidisciplinary expertise and infrastructure are often not available in low- and middle-income countries (LMIC) for pediatric cancers, such as neuroblastoma. Our goal was to review results of a Global Neuroblastoma Network (GNN) tumor board accessible to LMIC. METHODS: De-identified clinical cases presented via internet conference during a weekly GNN virtual tumor board from 2010 through 2020 were evaluated in a standardized format, including diagnostic imaging, pathology, therapy information, resource limitations, and questions for discussion. Information summarized included the presentations, a survey of the impact on care, and a resource questionnaire. RESULTS: Registered GNN participants included 575 individuals from 77 countries, with a median of 39 participants per session. Total 412 cases were presented from 32 countries, including 351 unique neuroblastoma patients, 52 follow-up cases, and nine non-neuroblastoma diagnoses. Twenty-eight educational sessions were presented. Limited critical resources for diagnostics and staging of cases included MYCN analysis (54.7%), metaiodobenzylguanidine (MIBG) scans (38.7%), and International Neuroblastoma Pathology Classification (49%). Therapies were also limited, with markedly decreased use of radiation and autologous stem cell transplant for high-risk cases, and no availability of anti-GD2 antibody in LMIC. Limited sampling with a post-presentation survey showed that 100% found the GNN helpful, and 70% altered the care plan based on the discussion. CONCLUSION: This report shows the utility of an international tumor board for LMIC focused on a challenging solid tumor where local expertise may be limited, with international multidisciplinary expert participation and educational sessions.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Neuroblastoma , 3-Iodobenzilguanidina , Criança , Humanos , Neuroblastoma/patologia , Cintilografia , Transplante Autólogo
20.
Environ Sci Pollut Res Int ; 29(6): 8694-8704, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34490579

RESUMO

Many studies have evaluated factors that influence the course of the COVID-19 pandemic in different countries. This multicountry study assessed the influence of democracy and other factors on the case fatality rate of COVID-19 during the early stage of the pandemic. We accessed the World Health Organization, World Bank, and the Democracy Index 2019 databases for data from the 148 countries. Multiple analyses were conducted to examine the association between the Democracy Index and case fatality rate of COVID-19. Within 148 countries, the percentage of the population aged 65 years and above (p = 0.0193), and health expenditure as a percentage of GDP (p = 0.0237) were positively associated with countries' case fatality rates. By contrast, hospital beds per capita helped to reduce the case fatality rates. In particular, the Democracy Index was positively associated with case fatality rates in a subgroup of 47 high-income countries. This study suggests that enhancing the health system with increased hospital beds and healthcare workforce per capita should reduce case fatality rate. The findings suggest that a higher Democracy Index is associated with more deaths from COVID-19 at the early stage of the pandemic, possibly due to the decreased ability of the government.


Assuntos
COVID-19 , Pandemias , Democracia , Humanos , SARS-CoV-2 , Organização Mundial da Saúde
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