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1.
Environ Monit Assess ; 196(3): 290, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383814

RESUMO

In this research, three numerical groundwater flow models, developed and calibrated from three equally plausible conceptual models over the Nasia Basin, have been used to assess groundwater resources variations over a transient period. The use of multiple numerical models reduces the effect of uncertainties in conceptual model formulation. All the three calibrated numerical models indicate an increasing trend of groundwater recharge and storage over the period of the groundwater level monitoring. This suggests that the prevailing erratic climatic conditions in the area are conducive for increasing groundwater recharge and storage in the terrain. The high-intensity, short duration rainfall patterns, attending climate change in the basin, enhance high levels of infiltration and percolation, leading to steadily increasing groundwater recharge. Groundwater recharge estimates from each of the models over the transient period appear to reflect the pattern of seasonal variations in rainfall in the region. Data from the models indicates a significant role of baseflow in sustaining perennial streamflow in the area. This presents a significant development in terms of groundwater-based adaptation projects, especially in agriculture. The trend of groundwater recharge in the Nasia Basin is in sync with regional groundwater storage variations estimated from the Gravity Recovery and Climate Experiment (GRACE) satellite data collected and processed over the Volta Basin. At the Volta Basin level, groundwater storage variations indicate a strong positive trend of increasing groundwater recharge from 2002 (beginning of the GRACE mission) to 2022 (end point of the data used for this research). Analysis of the GRACE data suggests that there is a cumulative increase in groundwater storage by 30 cm, representing approximately 120 km3 of groundwater over the period in the basin. This translates into approximately 15 mm/year of groundwater storage increase. Thus, at both the regional and local levels, groundwater appears to be responding positively to the impacts of erratic rainfall patterns observed in the area recently. The high-intensity, short duration rainfall patterns appear to favor significant groundwater recharge, resulting in a strong positive groundwater storage signal. The high positive groundwater storage signal suggests increasing groundwater resources potential in the area, indicating promising opportunities for groundwater-based climate change adaptation interventions.


Assuntos
Monitoramento Ambiental , Água Subterrânea , Monitoramento Ambiental/métodos , Agricultura , Estações do Ano , Modelos Teóricos
6.
Transfusion ; 59(1): 335-339, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30467850

RESUMO

BACKGROUND: Hemolysis at the time of graft infusion is one of the immediate complications in major ABO-incompatible allogeneic hematopoietic stem cell transplants (HSCTs). We conducted a retrospective analysis to evaluate the efficacy of donor-type fresh frozen plasma (FFP) in reducing isohemagglutinin titer and preventing hemolysis, as well as its effect on delayed red cell engraftment. MATERIALS AND METHODS: This is a single-center study on a series of 380 allogeneic HSCT between 2005 and 2015; of which 99 were either major (n = 74) or bidirectional (n = 25) ABO mismatched. Pre-transplant infusion of FFP, post-transplant complications and transfusion requirements were determined by retrospective review of individual medical records. Laboratory results were also reviewed for evidence of hemolysis and pure red cell aplasia (PRCA). RESULTS: Clinical manifestation of hemolysis attributable to ABO mismatch was present in one recipient of major ABO-incompatible peripheral blood stem cell (PBSC) with a titer of 64. Another recipient of major ABO-incompatible PBSC with a titer of 64 showed biochemical evidence of hemolysis. Both patients recovered with supportive treatment. Hemolysis did not occur in any patients with titer of 32 or less at the time of stem cell infusion. We were unable to demonstrate the influence of any variables on the incidence of PRCA. CONCLUSION: Our experience demonstrated that donor-type FFP is safe and effective in preventing acute hemolysis in major ABO-mismatched HSCT. We have also established the titer of 64 as the threshold that may cause hemolysis and therefore efforts should be made to reduce titer to below this level.


Assuntos
Sistema ABO de Grupos Sanguíneos/metabolismo , Transplante de Células-Tronco Hematopoéticas/métodos , Hemólise/fisiologia , Plasma/citologia , Adulto , Incompatibilidade de Grupos Sanguíneos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transplante de Células-Tronco de Sangue Periférico/métodos , Células-Tronco de Sangue Periférico/citologia , Estudos Retrospectivos
7.
Leuk Lymphoma ; 59(10): 2336-2341, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29345210

RESUMO

Diffuse large B-cell lymphoma (DLBCL) is a high-grade lymphoma that requires treatment. We retrospectively analyzed the impact of time from diagnosis-to-treatment (TDT) on progression-free survival (PFS) and overall survival (OS) in 581 R-CHOP-treated patients. TDT was defined as the interval between diagnostic biopsy date and day 1 R-CHOP. Cox regression showed stage 3-4 disease (p = .01) and longer TDT (HR 1.13, p =.031) were associated with shorter OS. Eastern Cooperative Oncology Group ≥2 (p = .02), stage 3-4 disease (p < .001), and longer TDT (HR 1.12, p = .028) predicted shorter PFS. The significant interactions between TDT with lactate dehydrogenase (LDH) and with disease stage prompted separate analyses in high versus normal LDH, and stage 3-4 versus 1-2 disease. Longer TDT was associated with shortened PFS and OS only with advanced stage, and, if high LDH was present. Treatment should be started as early as possible for high-tumor burden disease. Delaying treatment in patients with early stage or low LDH does not seem harmful.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Tempo para o Tratamento/estatística & dados numéricos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/mortalidade , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Singapura/epidemiologia , Adulto Jovem
8.
Clin Transplant ; 31(4)2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28135776

RESUMO

Allogeneic hemopoietic stem cell transplantation (allo-HSCT) poses a significant challenge to renal function due to multiple drug- and complication-related renal toxicity. In this single-center series of 216 adult Asian patients with a long and complete follow-up, 41 developed chronic kidney disease (CKD) giving a cumulative incidence of 19.0% at 25 years (median follow-up duration 7.84 years, range 2.0-27.7 years), but only two of the 41 patients reached stage 4 CKD and another two required dialysis. In contrast, acute kidney injury occurred in most patients, where glomerular filtration rate (GFR) suffered a mean fall of 50 mL/min/1.73 m2 at 6 months post-transplant compared with baseline. Suppression of renal function may last beyond 6 months but is potentially reversible, although not to baseline level in most patients. Analysis of a comprehensive range of 18 risk factors showed that older age, lower GFR at transplant, unrelated donor, diagnosis of AML, presence of diabetes mellitus at transplant, and duration of foscarnet use were significantly associated with CKD development, with the first three remaining as independent risks for CKD in multivariate analysis. Long-term survival is not affected by renal function, being 78.6% as compared to 85.5% for patients with low vs normal GFR at 2 years, respectively.


Assuntos
Rejeição de Enxerto/etiologia , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Complicações Pós-Operatórias , Insuficiência Renal Crônica/etiologia , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Taxa de Filtração Glomerular , Rejeição de Enxerto/epidemiologia , Sobrevivência de Enxerto , Doença Enxerto-Hospedeiro/epidemiologia , Humanos , Incidência , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Prognóstico , Insuficiência Renal Crônica/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Singapura/epidemiologia , Transplante Homólogo , Adulto Jovem
10.
Radiother Oncol ; 117(3): 419-24, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26603773

RESUMO

BACKGROUND AND PURPOSE: We aim to quantify the magnitude of the systematic and random setup errors at three different anatomical levels of the neck in Nasopharyngeal Carcinoma (NPC) when clivus matching is used, and recommend appropriate PTV margins for each level. MATERIAL AND METHODS: Thirty-six patients undergoing image-guided radiotherapy (IGRT) each with 9 scheduled CBCTs were reviewed. The magnitude of setup errors were measured at the level of the clivus, C4 and C7 vertebrae, before and after CBCT correction. The 3D displacements, systematic and random errors were calculated for each level. The appropriate PTV expansion was determined using Van Herk's formula. RESULTS: Mean 3D displacement was 1.88, 2.66 and 3.35 mm at the clivus, C4 and C7 before correction. The differences were statistically significant (p<0.05). The PTV margin required without correction was 2.33, 4.33 and 6.52 mm respectively. These were reduced to 1.20, 3.72 and 6.08 mm after CBCT corrections. CONCLUSIONS: Variability is seen in setup errors at the clivus, C4 and C7 vertebral levels. A variable planning margin approach with reduced margin at the clivus is recommended. Use of daily CBCT allows the PTV expansion to be reduced to 1.2 mm.


Assuntos
Neoplasias Nasofaríngeas/radioterapia , Erros de Configuração em Radioterapia/prevenção & controle , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Estudos Retrospectivos , Adulto Jovem
11.
Leuk Lymphoma ; 56(5): 1362-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25139689

RESUMO

To better understand predictive factors and improve the clinical outcome of allogeneic transplant for patients with Philadelphia positive acute lymphoblastic leukemia, we analyzed 67 Southeast Asian patients transplanted in our institutions. Multivariate analysis showed that disease status before transplant, year of transplant and, interestingly, French-American-British (FAB) subtype had a significant impact on overall survival (OS) and non-relapse mortality. Patients who were minimal residual disease (MRD) negative at transplant had a 3-year OS of 73% compared to those who were MRD positive (45%) and refractory (0%). The 3-year cumulative incidence of relapse was 18% and 36% for the MRD negative and positive groups, respectively. FAB L1 subtype had a significantly superior 3-year OS of 63% vs. 29% for L2 subtype. Pre-transplant use of a tyrosine kinase inhibitor significantly improved outcomes in univariate but not multivariate analysis, as it served to induce more patients into MRD negativity, which was the factor that directly improved transplant outcome.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Adolescente , Adulto , Sudeste Asiático , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasia Residual , Cromossomo Filadélfia , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Recidiva , Terapia de Salvação , Análise de Sobrevida , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem
13.
Ann Hematol ; 94(5): 761-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25519475

RESUMO

To better understand the predictive factors and improve clinical outcome of allogeneic transplant for patients with myelodysplastic syndrome (MDS), we retrospectively analyzed the post-transplant outcome of 60 Southeast Asian patients with MDS. Multivariate analysis showed that WHO classification-based Prognostic Scoring System (WPSS) significantly affect overall survival (OS), progression-free survival (PFS), cumulative incidence of relapse (CIR), and cumulative incidence of non-relapse mortality (CINRM). Stratified by WPSS into very low/low, intermediate, high, and very high-risk categories, 3-year OS was 100, 61, 37, and 18% (p = 0.02); PFS was 100, 55, 32, and 18% (p = 0.014); CIR was 12, 24, 38, and 59% (p = 0.024); CINRM was 0, 6, 12, and 26% (p = 0.037), respectively. WHO classification, Revised International Prognostic Scoring System (IPSS-R), IPSS-R-defined cytogenetic risk groups, donor gender, and acute and chronic graft vs host disease (GVHD) also influenced different aspects of transplant outcome. We found that WPSS is a powerful predictor of post-transplant outcome. WPSS provides an important model not only for prognostication but also for exploration of further post-transplant measures such as immunological maneuvers or novel therapy to improve the poor outcome of high-risk patients.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Síndromes Mielodisplásicas/terapia , Transplante Homólogo , Sudeste Asiático , Intervalo Livre de Doença , Feminino , Doença Enxerto-Hospedeiro/mortalidade , Doença Enxerto-Hospedeiro/patologia , Doença Enxerto-Hospedeiro/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/mortalidade , Síndromes Mielodisplásicas/patologia , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento
14.
Transfus Apher Sci ; 47(3): 345-50, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23032067

RESUMO

Peripheral blood stem cells (PBSC) have become the most common source of hematopoietic cells for allogeneic or autologous blood and marrow transplantation (BMT). We performed an evaluation of PBSC collections using three different apheresis systems in two major transplantation centers in Singapore. Patients undergoing autologous BMT and donors collecting for allogeneic BMT were harvested using the COBE Spectra, Haemonetics MCS+, or Baxter Amicus. There were 99 Spectra collections (61 were autologous), 81 MCS+ collections (35 were autologous) and 38 Amicus collections (33 were autologous). Our data shows that the Amicus not only processed larger peripheral blood volumes but also yielded larger PBSC volume (P-value<0.05). In terms of PBSC products, the Spectra produced more WBC, WBC/liter blood processed, and WBC/kg (P-value<0.05). The Spectra and MCS+ produced comparable amount of CD34+ cells. Amicus collected 50% less platelets compared to Spectra and MCS+. The total CD34+ cells in the PBSC products was linearly correlated to the circulating CD34+ cells using Spectra, MCS+, and Amicus. Our results suggest that, compared to MCS+ and Amicus, collecting PBSC using the COBE Spectra can produce more WBC with a similar number of CD34+ cells. With a linear correlation of circulating CD34+ cells to the total CD34+ cells in the products, the availability of an automated procedure, no rotating seal, and a small extracorporeal volume, the Spectra appears to be the preferred machine for PBSC collection.


Assuntos
Remoção de Componentes Sanguíneos/instrumentação , Células-Tronco Hematopoéticas/citologia , Transplante de Células-Tronco de Sangue Periférico/métodos , Adulto , Idoso , Remoção de Componentes Sanguíneos/métodos , Transplante de Medula Óssea/instrumentação , Transplante de Medula Óssea/métodos , Feminino , Transplante de Células-Tronco Hematopoéticas/instrumentação , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Transplante de Células-Tronco de Sangue Periférico/instrumentação , Adulto Jovem
15.
Cytotherapy ; 14(7): 851-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22799277

RESUMO

BACKGROUND AIMS: Cytokine-induced killer (CIK) cells have shown remarkable cytotoxicity against various tumors in vitro and in animal studies. We report on the clinical outcome of autologous CIK cells for patients with acute (AML) and chronic (CML) myeloid leukemia in remission. METHODS: Eleven of the 13 recruited AML patients undergoing autologous peripheral blood stem cell transplant (autoPBSCT) were given autologous CIK cell infusion upon engraftment post-transplant and followed-up for disease relapse. Eleven CML patients on Imatinib with residual disease detectable by polymerase chain reaction (PCR) were given infusion and monitored by quantitation of the bcr-abl transcript. RESULTS: Despite the presence of interferon (IFN)-γ-secreting T cells against various AML- and CML-associated peptides at sporadic time-points and demonstration of in vitro cytotoxicity of CIK cells against autologous and allogeneic AML targets, there was no survival benefit in AML patients post-autoPBSCT given CIK cells compared with historical controls. For CML patients, all continued to have a detectable bcr-abl transcript fluctuating within a range comparable to their pre-treatment baseline, although two had a transient but non-sustainable disappearance of bcr-abl transcript. There were no adverse reactions except for fever within the first day of infusion. CONCLUSIONS: Our small series, while confirming safety, failed to demonstrate a clinical benefit of autologous CIK cells given in its current form for AML and CML. Further manipulation of CIK cells to improve anti-leukemic potency and specificity, together with the preparation of patients to create a more conducive milieu for in vivo expansion and persistence of infused CIK cells, should be explored.


Assuntos
Células Matadoras Induzidas por Citocinas/transplante , Imunoterapia Adotiva , Leucemia Mielogênica Crônica BCR-ABL Positiva , Leucemia Mieloide Aguda , Transplante de Células-Tronco de Sangue Periférico , Adulto , Benzamidas , Complexo CD3/metabolismo , Antígeno CD56/metabolismo , Feminino , Proteínas de Fusão bcr-abl/análise , Humanos , Mesilato de Imatinib , Imunoterapia , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/terapia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/terapia , Transplante de Células-Tronco de Sangue Periférico/métodos , Piperazinas/uso terapêutico , Pirimidinas/uso terapêutico
20.
Adv Hematol ; 2009: 547582, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19960058

RESUMO

Background. Intravenous alemtuzumab and fludarabine are effective in combination for the treatment of chronic lymphocytic leukemia (CLL), but require hospital visits for intravenous injection. We performed a pilot study to assess the safety and efficacy of outpatient-based oral fludarabine with subcutaneous alemtuzumab (OFSA) for the treatment of relapsed/refractory CLL. Results. Depending on their response, patients were given two to six 28-day cycles of subcutaneous alemtuzumab 30 mg on days 1,3, and 5 and oral fludarabine 40 mg/m(2)/day for 5 days. Median patient age was 74. The lymphocyte counts of all five patients fell after the 1st cycle of treatment and reached normal/low levels on completion of 2 to 6 cycles of therapy. Platelet counts and hemoglobin were unaffected. All five patients achieved complete hematological remission, while two attained minimal residual disease negativity on 4-color flow cytometry. Conclusions. Our OFSA regimen was effective in elderly Asian patients with relapsed/refractory CLL, and it should be investigated further.

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