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1.
Blood ; 137(4): 459-470, 2021 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-33075812

RESUMEN

Adult T-cell leukemia/lymphoma (ATL) is a highly aggressive T-cell malignancy that arises in a proportion of individuals who are long-term carriers of human T-lymphotropic virus type 1. The median survival of aggressive subtypes is 8 to 10 months; with chemotherapy-based approaches, overall survival has remained largely unchanged in the ∼35 years since ATL was first described. Through the use of 4 representative case studies, we highlight advances in the biological understanding of ATL and the use of novel therapies such as mogamulizumab, as well as how they are best applied to different subtypes of ATL. We discuss the implementation of molecular methods that may guide diagnosis or treatment, although we accept that these are not universally available. In particular, we acknowledge discrepancies in treatment between different countries, reflecting current drug licensing and the difficulties in making treatment decisions in a rare disease, with limited high-quality clinical trial data.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Trasplante de Células Madre Hematopoyéticas , Leucemia-Linfoma de Células T del Adulto/terapia , Terapias en Investigación , Anciano , Aloinjertos , Anticuerpos Monoclonales Humanizados/uso terapéutico , Antineoplásicos Inmunológicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Terapia Combinada , Ciclofosfamida/administración & dosificación , Dexametasona/administración & dosificación , Doxorrubicina/administración & dosificación , Etopósido/administración & dosificación , Femenino , Virus Linfotrópico T Tipo 1 Humano/fisiología , Humanos , Interferón-alfa/administración & dosificación , Leucemia-Linfoma de Células T del Adulto/tratamiento farmacológico , Leucemia-Linfoma de Células T del Adulto/radioterapia , Leucemia-Linfoma de Células T del Adulto/virología , Masculino , Metotrexato/administración & dosificación , Persona de Mediana Edad , Pautas de la Práctica en Medicina , Prednisona/administración & dosificación , Raltegravir Potásico/administración & dosificación , Recurrencia , Inducción de Remisión , Vincristina/administración & dosificación , Activación Viral , Zidovudina/administración & dosificación
2.
Environ Sci Technol ; 56(5): 3225-3233, 2022 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-35142487

RESUMEN

Subsurface microbial (biogenic) methane production is an important part of the global carbon cycle that has resulted in natural gas accumulations in many coal beds worldwide. Laboratory studies suggest that complex carbon-containing nutrients (e.g., yeast or algae extract) can stimulate methane production, yet the effectiveness of these nutrients within coal beds is unknown. Here, we use downhole monitoring methods in combination with deuterated water (D2O) and a 200-liter injection of 0.1% yeast extract (YE) to stimulate and isotopically label newly generated methane. A total dissolved gas pressure sensor enabled real-time gas measurements (641 days preinjection and for 478 days postinjection). Downhole samples, collected with subsurface environmental samplers, indicate that methane increased 132% above preinjection levels based on isotopic labeling from D2O, 108% based on pressure readings, and 183% based on methane measurements 266 days postinjection. Demonstrating that YE enhances biogenic coalbed methane production in situ using multiple novel measurement methods has immediate implications for other field-scale biogenic methane investigations, including in situ methods to detect and track microbial activities related to the methanogenic turnover of recalcitrant carbon in the subsurface.


Asunto(s)
Carbón Mineral , Metano , Carbono , Gas Natural
3.
Clin Infect Dis ; 73(7): 1257-1265, 2021 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-33956965

RESUMEN

BACKGROUND: Levofloxacin prophylaxis is recommended to prevent gram-negative bloodstream infections (BSIs) in patients with prolonged chemotherapy-induced neutropenia. However, increasing fluoroquinolone resistance may decrease the effectiveness of this approach. METHODS: We assessed the prevalence of colonization with fluoroquinolone-resistant Enterobacterales (FQRE) among patients admitted for hematopoietic cell transplantation (HCT) from November 2016 to August 2019 and compared the risk of gram-negative BSI between FQRE-colonized and noncolonized patients. All patients received levofloxacin prophylaxis during neutropenia. Stool samples were collected upon admission for HCT and weekly thereafter until recovery from neutropenia, and underwent selective culture for FQRE. All isolates were identified and underwent antimicrobial susceptibility testing by broth microdilution. FQRE isolates also underwent whole-genome sequencing. RESULTS: Fifty-four of 234 (23%) patients were colonized with FQRE prior to HCT, including 30 of 119 (25%) allogeneic and 24 of 115 (21%) autologous HCT recipients. Recent antibacterial use was associated with FQRE colonization (P = .048). Ninety-one percent of colonizing FQRE isolates were Escherichia coli and 29% produced extended-spectrum ß-lactamases. Seventeen (31%) FQRE-colonized patients developed gram-negative BSI despite levofloxacin prophylaxis, compared to only 2 of 180 (1.1%) patients who were not colonized with FQRE on admission (P < .001). Of the 17 gram-negative BSIs in FQRE-colonized patients, 15 (88%) were caused by FQRE isolates that were genetically identical to the colonizing strain. CONCLUSIONS: Nearly one-third of HCT recipients with pretransplant FQRE colonization developed gram-negative BSI while receiving levofloxacin prophylaxis, and infections were typically caused by their colonizing strains. In contrast, levofloxacin prophylaxis was highly effective in patients not initially colonized with FQRE.


Asunto(s)
Bacteriemia , Trasplante de Células Madre Hematopoyéticas , Antibacterianos/uso terapéutico , Profilaxis Antibiótica , Bacteriemia/tratamiento farmacológico , Bacteriemia/prevención & control , Fluoroquinolonas/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Levofloxacino/uso terapéutico , Estudios Retrospectivos , Receptores de Trasplantes
4.
Biol Blood Marrow Transplant ; 26(4): 789-797, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31891814

RESUMEN

Reduced-intensity conditioning (RIC) regimens, improved HLA matching, and better supportive care allow allogeneic stem cell transplant (alloSCT) to be offered to older patients. Only a small percentage of eligible patients between ages 65 and 74 years actually undergo alloSCT, and comprehensive outcome data from the aging population are still lacking. We examined the outcome of older patients who underwent alloSCT using melphalan-based RIC for hematologic malignancies at our institution. We identified 125 patients older than 65 years (median, 69; range, 66 to 77) who underwent matched related donor, matched unrelated donor, or combined haploidentical/umbilical cord alloSCT between 2012 through November, 2017. Among them, 52 (41.6%) and 70 (56%) had, respectively, intermediate and high/very high Center for International Blood and Marrow Transplant Research (CIBMTR) disease risk index (DRI). One hundred six patients (85%) received fludarabine/melphalan-based RIC regimen with either antithymocyte globulin (ATG) or alemtuzumab. The median time to neutrophil engraftment was 13 days (range, 8 to 37) and platelet engraftment 17 days (range, 9 to 169). The cumulative incidence of nonrelapse mortality was 11.5% at 100 days and 30.1% and 34.8% at 1 and 2 years, respectively. The cumulative incidence of relapse was 35% and 40% at 1 and 2 years. The cumulative incidence of grades II to IV acute graft-versus-host disease (GVHD) at day 100 and 6 months was 29.5% and 34.5%, and chronic GVHD at 6, 12, and 24 months was 2.5%, 5.2%, and 6.3%, respectively. With a median follow-up of 32 months, the 1-, 2-, and 3-year progression-free survival (PFS) was 34.6%, 24.4%, and 16.5%, respectively. The graft GVHD-free survival was 24.6%, 16.1%, and 9.3%, respectively. The 1-, 2-, and 3-year overall survival (OS) was 44.5%, 30.7%, and 26.5%, respectively. In multivariable analysis, low albumin was predictive of poor PFS and OS and high hematopoietic cell transplantation-specific comorbidity index, and CIBMTR DRI was predictive of worse graft GVHD-free survival. Among long-term survivors the median Karnofsky performance status was 80. Older patients, even when referred with advanced disease, can benefit from melphalan-based alloSCT with HLA-matched or alternative donor sources without discernible impact of donor source on outcome. Using alemtuzumab- or ATG-based in vivo T cell depletion, the incidence of chronic GVHD is extremely low. Performance status in survivors is excellent. Better predictors for outcome in this patient population need to be identified.


Asunto(s)
Enfermedad Injerto contra Huésped , Neoplasias Hematológicas , Trasplante de Células Madre Hematopoyéticas , Anciano , Enfermedad Injerto contra Huésped/etiología , Neoplasias Hematológicas/terapia , Humanos , Recurrencia Local de Neoplasia , Trasplante de Células Madre , Acondicionamiento Pretrasplante
5.
Biol Blood Marrow Transplant ; 25(2): e60-e64, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30661542

RESUMEN

Donor-specific HLA antibodies (DSAs) have been associated with an increased risk of graft failure. To decrease DSA levels and reduce the risk of graft failure in haploidentical cord blood transplantation recipients, we studied the effect of bortezomib (BTZ) and i.v. immune globulin (IVIG) pretransplantation. Between 2012 and 2016, 14 patients with a DSA level >2000 mean fluorescence intensity (MFI) to 1 or more mismatched HLA alleles of haploidentical donors, cord blood donors, or both were treated with BTZ and IVIG. Fourteen patients received a median of 4 doses (range, 2 to 8 doses) of BTZ 1.3 mg/m2 and a median total IVIG of 2 g/kg before transplantation. Only 2 of 14 patients attained a reduction in MFI to <2000 with this combination. After additional IVIG (n = 8), rituximab (n = 4), and/or plasmapheresis (n = 11), 12 of 14 patients were desensitized to a DSA level <2000 MFI at the time of engraftment. All obtained initial hematopoietic reconstitution, and no DSA rebound phenomenon was observed. Responders with DSA MFI <2000 to the haploidentical donor by transplantation engrafted at a rate comparable to that of historical controls, whereas engraftment in nonresponders took 3 times as long. BTZ and IVIG alone do not appear sufficient to rapidly induce DSA desensitization, and persistent DSAs to a haploidentical donor lead to delayed count recovery. Our data suggest that additional pretreatment with BTZ and IVIG in combination with the conditioning regimen may help abrogate the rebound phenomenon observed with plasmapheresis.


Asunto(s)
Bortezomib/administración & dosificación , Trasplante de Células Madre de Sangre del Cordón Umbilical , Antígenos HLA/sangre , Inmunoglobulinas Intravenosas/administración & dosificación , Isoanticuerpos/sangre , Mieloma Múltiple , Acondicionamiento Pretrasplante , Adulto , Anciano , Aloinjertos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mieloma Múltiple/sangre , Mieloma Múltiple/mortalidad , Mieloma Múltiple/terapia , Estudios Retrospectivos
6.
Biol Blood Marrow Transplant ; 25(3): 466-473, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30414955

RESUMEN

Adoptive immunotherapy has shown efficacy in patients with relapsed/refractory acute myelogenous leukemia (AML). We conducted a prospective evaluation of cord blood (CB)-based adoptive cell therapy following salvage chemotherapy in patients with AML or myelodysplastic syndrome (MDS) and describe the safety and early outcomes of this approach. To enhance the antileukemic effect, we selected CB units (CBUs) with a shared inherited paternal antigen (IPA) and/or noninherited maternal antigen (NIMA) match with the recipients. Furthermore, the CBUs had total nucleated cell (TNC) dose <2.5 × 107/kg and were at least 4/6 HLA-matched with the patients; a higher allele-level match was preferred. Heavily pretreated adult patients with AML/MDS were enrolled. CBU searches were performed for 50 patients. CBUs with shared IPA targets were identified for all, and CBUs with NIMA matches were found for 80%. Twenty-one patients underwent treatment (AML, primary induction failure, n = 8; refractory relapse, n = 10, including 7 recipients of previous allogeneic HSCT; blast crisis chronic myelogenous leukemia, n = 1; MDS, n = 2). Most received combination chemotherapy; those not fit for intensive treatment received a hypomethylating agent. Response was defined as <10% residual blasts in hypocellular bone marrow at approximately 2 weeks after treatment. Ten of the 19 evaluable patients responded, including 5 of the 7 recipients of previous transplant. Response was seen in 4 of 4 patients with full CBU-derived chimerism, 2 of 2 of those with partial, low-level chimerism and 4 of 12 of the recipients with no detectable CBU chimerism. The most common adverse events were infections (bacterial, n = 5; viral, n = 2; fungal, n = 5). Grade IV acute graft-versus-host disease (GVHD) developed in 2 patients with full CBU chimerism; 2 other patients had grade 1 skin GVHD. A total of 11 patients died, 7 from disease recurrence and 4 from infections (1 early death; the other 3 in remission at the time of death). Overall, 12 patients proceeded to allogeneic HSCT; of those, 7 had responded to treatment, 3 had not (and had received additional therapy), and 2 had persistent minimal residual disease. In conclusion, the use of CB as adoptive immunotherapy in combination with salvage chemotherapy for patients with refractory AML/MDS is feasible, can induce disease control, can serve as a bridge to allogeneic HSCT, and has an acceptable incidence of adverse events. Alloreactivity was enhanced through the selection of CBUs targeting a shared IPA and/or NIMA match with the patients. CBUs with lower cell doses, already available in the CB bank and unlikely to be adequate grafts for adult transplants, can be used for cell therapy within a short time frame.


Asunto(s)
Sangre Fetal/trasplante , Inmunoterapia Adoptiva/métodos , Leucemia Mieloide Aguda/terapia , Adolescente , Adulto , Quimerismo , Femenino , Enfermedad Injerto contra Huésped/etiología , Humanos , Inmunoterapia Adoptiva/efectos adversos , Infecciones/etiología , Leucemia Mieloide Aguda/complicaciones , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/complicaciones , Síndromes Mielodisplásicos/terapia , Estudios Prospectivos , Terapia Recuperativa , Resultado del Tratamiento
7.
Haematologica ; 104(5): 993-1003, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30573506

RESUMEN

Mogamulizumab, a humanized defucosylated anti-C-C chemokine receptor 4 monoclonal antibody, has been approved in Japan for the treatment of C-C chemokine receptor 4-positive adult T-cell leukemia/lymphoma (ATL). This phase II study evaluated efficacy and safety of mogamulizumab in ATL patients with acute, lymphoma, and chronic subtypes with relapsed/refractory, aggressive disease in the US, Europe, and Latin America. With stratification by subtype, patients were randomized 2:1 to intravenous mogamulizumab 1.0 mg/kg once weekly for 4 weeks and biweekly thereafter (n=47) or investigator's choice of chemotherapy (n=24). The primary end point was confirmed overall response rate (cORR) confirmed on a subsequent assessment at 8 weeks by blinded independent review. ORR was 11% (95%CI: 4-23%) and 0% (95%CI: 0-14%) in the mogamulizumab and chemotherapy arms, respectively. Best response was 28% and 8% in the respective arms. The observed hazard ratio for progression-free survival was 0.71 (95%CI: 0.41-1.21) and, after post hoc adjustment for performance status imbalance, 0.57 (95%CI: 0.337-0.983). The most frequent treatment-related adverse (grade ≥3) events with mogamulizumab were infusion-related reaction and thrombocytopenia (each 9%). Relapsed/refractory ATL is an aggressive, poor prognosis disease with a high unmet need. Investigator's choice chemotherapy did not result in tumor response in this trial; however, mogamulizumab treatment resulted in 11% cORR, with a tolerable safety profile.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Resistencia a Antineoplásicos/efectos de los fármacos , Leucemia-Linfoma de Células T del Adulto/tratamiento farmacológico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Terapia Recuperativa , Adulto , Anciano , Anciano de 80 o más Años , Aminopterina/administración & dosificación , Aminopterina/análogos & derivados , Anticuerpos Monoclonales Humanizados/administración & dosificación , Cisplatino/administración & dosificación , Citarabina/administración & dosificación , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Dexametasona/administración & dosificación , Femenino , Estudios de Seguimiento , Humanos , Agencias Internacionales , Leucemia-Linfoma de Células T del Adulto/patología , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Oxaliplatino/administración & dosificación , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia , Adulto Joven , Gemcitabina
8.
Biol Blood Marrow Transplant ; 24(2): 359-365, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29128555

RESUMEN

Limited studies have reported on outcomes for lymphoid malignancy patients receiving alternative donor allogeneic stem cell transplants. We have previously described combining CD34-selected haploidentical grafts with umbilical cord blood (haplo-cord) to accelerate neutrophil and platelet engraftment. Here, we examine the outcome of patients with lymphoid malignancies undergoing haplo-cord transplantation at the University of Chicago and Weill Cornell Medical College. We analyzed 42 lymphoma and chronic lymphoblastic leukemia (CLL) patients who underwent haplo-cord allogeneic stem cell transplantation. Patients underwent transplant for Hodgkin lymphoma (n = 9, 21%), CLL (n = 5, 12%) and non-Hodgkin lymphomas (n = 28, 67%), including 13 T cell lymphomas. Twenty-four patients (52%) had 3 or more lines of therapies. Six (14%) and 1 (2%) patients had prior autologous and allogeneic stem cell transplant, respectively. At the time of transplant 12 patients (29%) were in complete remission, 18 had chemotherapy-sensitive disease, and 12 patients had chemotherapy-resistant disease. Seven (17%), 11 (26%), and 24 (57%) patients had low, intermediate, and high disease risk index before transplant. Comorbidity index was evenly distributed among 3 groups, with 13 (31%), 14 (33%), and 15 (36%) patients scoring 0, 1 to 2, and ≥3. Median age for the cohort was 49 years (range, 23 to 71). All patients received fludarabine/melphalan/antithymocyte globulin conditioning regimen and post-transplant graft-versus-host disease (GVHD) prophylaxis with tacrolimus and mycophenolate mofetil. The median time to neutrophil engraftment was 11 days (range, 9 to 60) and to platelet engraftment 19.5 days (range, 11 to 88). Cumulative incidence of nonrelapse mortality was 11.6% at 100 days and 19 % at one year. Cumulative incidence of relapse was 9.3% at 100 days and 19% at one year. With a median follow-up of survivors of 42 months, the 3-year rates of GVHD relapse free survival, progression-free survival, and overall survival were 53%, 62%, and 65%, respectively, for these patients. Only 8% of the survivors had chronic GVHD. In conclusion, haplo-cord transplantation offers a transplant alternative for patients with recurrent or refractory lymphoid malignancies who lack matching donors. Both neutrophil and platelet count recovery is rapid, nonrelapse mortality is limited, excellent disease control can be achieved, and the incidence of chronic GVHD is limited. Thus, haplo-cord achieves high rates of engraftment and encouraging results.


Asunto(s)
Leucemia Linfocítica Crónica de Células B/terapia , Linfoma/terapia , Adulto , Anciano , Trasplante de Células Madre de Sangre del Cordón Umbilical , Enfermedad Injerto contra Huésped/etiología , Enfermedad Injerto contra Huésped/prevención & control , Humanos , Leucemia Linfocítica Crónica de Células B/complicaciones , Leucemia Linfocítica Crónica de Células B/mortalidad , Linfoma/complicaciones , Linfoma/mortalidad , Persona de Mediana Edad , Premedicación/métodos , Análisis de Supervivencia , Acondicionamiento Pretrasplante/métodos , Trasplante Haploidéntico , Trasplante Homólogo , Resultado del Tratamiento , Adulto Joven
9.
Biol Blood Marrow Transplant ; 24(2): 288-293, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29061534

RESUMEN

Administration of granulocyte colony-stimulating factor (G-CSF) after autologous peripheral blood stem cell transplantation (PBSCT) is generally recommended to reduce the duration of severe neutropenia; however, data regarding the optimal timing of G-CSFs post-transplantation are limited and conflicting. This retrospective study was performed at NewYork-Presbyterian/Weill Cornell Medical Center between November 5, 2013, and August 9, 2016, of adult inpatient autologous PBSCT recipients who received G-CSF empirically starting on day +5 (early) versus on those who received G-CSF on day +12 only if absolute neutrophil count (ANC) was <0.5 × 109/L (ANC-driven). G-CSF was dosed at 300 µg in patients weighing <75 kg and 480 µg in those weighing ≥75 kg. One hundred consecutive patients underwent autologous PBSCT using either the early (n = 50) or ANC-driven (n = 50) G-CSF regimen. Patient and transplantation characteristics were comparable in the 2 groups. In the ANC-driven group, 24% (n = 12) received G-CSF on day +12 and 60% (n = 30) started G-CSF earlier due to febrile neutropenia or at the physician's discretion, 6% (n = 3) started after day +12 at the physician's discretion, and 10% (n = 5) did not receive any G-CSF. The median start day of G-CSF therapy was day +10 in the ANC-driven group versus day +5 in the early group (P < .0001). For the primary outcome, the median time to neutrophil engraftment was 12 days (interquartile range [IQR] 11-13 days) in the early group versus 13 days (IQR, 12-14 days) in the ANC-driven group (P = .07). There were no significant between-group differences in time to platelet engraftment, 1-year relapse rate, or 1-year overall survival. The incidence of febrile neutropenia was 74% in the early group versus 90% in the ANC-driven group (P = .04); however, there was no significant between-group difference in the incidence of positive bacterial cultures or transfer to the intensive care unit. The duration of G-CSF administration until neutrophil engraftment was 6 days in the early group versus 3 days in the ANC-driven group (P < .0001). The median duration of post-transplantation hospitalization was 15 days (IQR, 14-19 days) in the early group versus 16 days (IQR, 15-22 days) in the ANC-driven group (P = .28). Our data show that early initiation of G-CSF (on day +5) and ANC-driven initiation of G-CSF following autologous PBSCT were associated with a similar time to neutrophil engraftment, length of stay post-transplantation, and 1-year overall survival.


Asunto(s)
Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Trasplante de Células Madre de Sangre Periférica/métodos , Anciano , Femenino , Supervivencia de Injerto , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Neutrófilos/citología , Trasplante de Células Madre de Sangre Periférica/mortalidad , Estudios Retrospectivos , Tasa de Supervivencia , Factores de Tiempo , Trasplante Autólogo/métodos , Trasplante Autólogo/mortalidad
11.
Environ Sci Technol ; 51(3): 1537-1543, 2017 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-27997145

RESUMEN

Microbially induced calcite precipitation (MICP) has been widely researched recently due to its relevance for subsurface engineering applications including sealing leakage pathways and permeability modification. These applications of MICP are inherently difficult to monitor nondestructively in time and space. Nuclear magnetic resonance (NMR) can characterize the pore size distributions, porosity, and permeability of subsurface formations. This investigation used a low-field NMR well-logging probe to monitor MICP in a sand-filled bioreactor, measuring NMR signal amplitude and T2 relaxation over an 8 day experimental period. Following inoculation with the ureolytic bacteria, Sporosarcina pasteurii, and pulsed injections of urea and calcium substrate, the NMR measured water content in the reactor decreased to 76% of its initial value. T2 relaxation distributions bifurcated from a single mode centered about approximately 650 ms into a fast decaying population (T2 less than 10 ms) and a larger population with T2 greater than 1000 ms. The combination of changes in pore volume and surface minerology accounts for the changes in the T2 distributions. Destructive sampling confirmed final porosity was approximately 88% of the original value. These results indicate the low-field NMR well-logging probe is sensitive to the physical and chemical changes caused by MICP in a laboratory bioreactor.


Asunto(s)
Carbonato de Calcio/química , Sporosarcina/metabolismo , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Porosidad
13.
Environ Sci Technol ; 50(7): 4111-7, 2016 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-26911511

RESUMEN

A primary environmental risk from unconventional oil and gas development or carbon sequestration is subsurface fluid leakage in the near wellbore environment. A potential solution to remediate leakage pathways is to promote microbially induced calcium carbonate precipitation (MICP) to plug fractures and reduce permeability in porous materials. The advantage of microbially induced calcium carbonate precipitation (MICP) over cement-based sealants is that the solutions used to promote MICP are aqueous. MICP solutions have low viscosities compared to cement, facilitating fluid transport into the formation. In this study, MICP was promoted in a fractured sandstone layer within the Fayette Sandstone Formation 340.8 m below ground surface using conventional oil field subsurface fluid delivery technologies (packer and bailer). After 24 urea/calcium solution and 6 microbial (Sporosarcina pasteurii) suspension injections, the injectivity was decreased (flow rate decreased from 1.9 to 0.47 L/min) and a reduction in the in-well pressure falloff (>30% before and 7% after treatment) was observed. In addition, during refracturing an increase in the fracture extension pressure was measured as compared to before MICP treatment. This study suggests MICP is a promising tool for sealing subsurface fractures in the near wellbore environment.


Asunto(s)
Carbonato de Calcio/química , Precipitación Química , Sporosarcina/metabolismo , Montana , Porosidad , Presión , Reología , Tomografía Computarizada por Rayos X
15.
ACS Appl Mater Interfaces ; 16(2): 2075-2085, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38176018

RESUMEN

Microbially induced calcium carbonate precipitation (MICP) has emerged as a novel technology with the potential to produce building materials through lower-temperature processes. The formation of calcium carbonate bridges in MICP allows the biocementation of aggregate particles to produce biobricks. Current approaches require several pulses of microbes and mineralization media to increase the quantity of calcium carbonate minerals and improve the strength of the material, thus leading to a reduction in sustainability. One potential technique to improve the efficiency of strength development involves trapping the bacteria on the aggregate surfaces using silane coupling agents such as positively charged 3-aminopropyl-methyl-diethoxysilane (APMDES). This treatment traps bacteria on sand through electrostatic interactions that attract negatively charged walls of bacteria to positively charged amine groups. The APMDES treatment promoted an abundant and immediate association of bacteria with sand, increasing the spatial density of ureolytic microbes on sand and promoting efficient initial calcium carbonate precipitation. Though microbial viability was compromised by treatment, urea hydrolysis was minimally affected. Strength was gained much more rapidly for the APMDES-treated sand than for the untreated sand. Three injections of bacteria and biomineralization media using APMDES-treated sand led to the same strength gain as seven injections using untreated sand. The higher strength with APMDES treatment was not explained by increased calcium carbonate accrual in the structure and may be influenced by additional factors such as differences in the microstructure of calcium carbonate bridges between sand particles. Overall, incorporating pretreatment methods, such as amine silane coupling agents, opens a new avenue in biomineralization research by producing materials with an improved efficiency and sustainability.


Asunto(s)
Arena , Sporosarcina , Silanos , Bacterias , Carbonatos , Carbonato de Calcio/química , Aminas , Precipitación Química
16.
Cancer Res ; 84(1): 101-117, 2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-37801604

RESUMEN

Exportin-1 (XPO1), the main soluble nuclear export receptor in eukaryotic cells, is frequently overexpressed in diffuse large B-cell lymphoma (DLBCL). A selective XPO1 inhibitor, selinexor, received approval as single agent for relapsed or refractory (R/R) DLBCL. Elucidating the mechanisms by which XPO1 overexpression supports cancer cells could facilitate further clinical development of XPO1 inhibitors. We uncovered here that XPO1 overexpression increases tolerance to genotoxic stress, leading to a poor response to chemoimmunotherapy. Upon DNA damage induced by MYC expression or exogenous compounds, XPO1 bound and exported EIF4E and THOC4 carrying DNA damage repair mRNAs, thereby increasing synthesis of DNA damage repair proteins under conditions of increased turnover. Consequently, XPO1 inhibition decreased the capacity of lymphoma cells to repair DNA damage and ultimately resulted in increased cytotoxicity. In a phase I clinical trial conducted in R/R DLBCL, the combination of selinexor with second-line chemoimmunotherapy was tolerated with early indication of efficacy. Overall, this study reveals that XPO1 overexpression plays a critical role in the increased tolerance of cancer cells to DNA damage while providing new insights to optimize the clinical development of XPO1 inhibitors. SIGNIFICANCE: XPO1 regulates the dynamic ribonucleoprotein nuclear export in response to genotoxic stress to support tolerance and can be targeted to enhance the sensitivity of cancer cells to endogenous and exogenous DNA damage. See related commentary by Knittel and Reinhardt, p. 3.


Asunto(s)
Linfoma de Células B Grandes Difuso , Linfoma no Hodgkin , Humanos , Transporte Activo de Núcleo Celular , Carioferinas/metabolismo , Línea Celular Tumoral , Hidrazinas/farmacología , Receptores Citoplasmáticos y Nucleares/genética , Receptores Citoplasmáticos y Nucleares/metabolismo , Daño del ADN , Linfoma no Hodgkin/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , ARN Mensajero/genética , ARN Mensajero/metabolismo
17.
Cancer ; 119(18): 3309-17, 2013 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-23896932

RESUMEN

BACKGROUND: An increased risk of non-Hodgkin lymphoma (NHL) has been observed among individuals with occupational exposure to benzene, but the risk among those living near benzene release sites has not been well described. METHODS: To investigate the spatial patterns of NHL incidence and the association between NHL incidence and distance to benzene release sites, the authors linked and geocoded data on benzene release sites in Georgia from 1988 to 1998 using the Environmental Protection Agency's (EPA) Toxics Release Inventory (TRI), census tract level population statistics, and NHL incidence from the Georgia Comprehensive Cancer Registry (GCCR) from 1999 to 2008. Standardized incidence ratios were mapped by census tract, and a Poisson regression was performed on NHL and NHL subtype incidence data using the mean distance between the tract centroids and release sites as markers of exposure. Cluster analyses were conducted at the global, local, and focal levels. RESULTS: Poisson regression indicated that, for every mile the average distance to benzene release sites increased, there was an expected 0.31% decrease in the risk of NHL. Similar results were observed for all NHL subtypes analyzed. Clusters of NHL were spatially associated with benzene release sites located in metropolitan areas, but not with release sites in other areas of the state. CONCLUSIONS: NHL incidence was significantly higher in census tracts that were closer, on average, to benzene release sites. Additional studies are needed to examine spatial patterns of NHL incidence in other geographic regions and interactions between benzene and other exposures.


Asunto(s)
Benceno/análisis , Benceno/envenenamiento , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/análisis , Linfoma no Hodgkin/inducido químicamente , Linfoma no Hodgkin/epidemiología , Adulto , Análisis por Conglomerados , Femenino , Georgia/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Distribución de Poisson , Programa de VERF , Estados Unidos , United States Environmental Protection Agency , Adulto Joven
18.
Environ Sci Technol ; 47(1): 142-9, 2013 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-22913538

RESUMEN

Mitigation strategies for sealing high permeability regions in cap rocks, such as fractures or improperly abandoned wells, are important considerations in the long term security of geologically stored carbon dioxide (CO(2)). Sealing technologies using low-viscosity fluids are advantageous in this context since they potentially reduce the necessary injection pressures and increase the radius of influence around injection wells. Using aqueous solutions and suspensions that can effectively promote microbially induced mineral precipitation is one such technology. Here we describe a strategy to homogenously distribute biofilm-induced calcium carbonate (CaCO(3)) precipitates in a 61 cm long sand-filled column and to seal a hydraulically fractured, 74 cm diameter Boyles Sandstone core. Sporosarcina pasteurii biofilms were established and an injection strategy developed to optimize CaCO(3) precipitation induced via microbial urea hydrolysis. Over the duration of the experiments, permeability decreased between 2 and 4 orders of magnitude in sand column and fractured core experiments, respectively. Additionally, after fracture sealing, the sandstone core withstood three times higher well bore pressure than during the initial fracturing event, which occurred prior to biofilm-induced CaCO(3) mineralization. These studies suggest biofilm-induced CaCO(3) precipitation technologies may potentially seal and strengthen fractures to mitigate CO(2) leakage potential.


Asunto(s)
Contaminantes Atmosféricos/química , Biopelículas , Carbonato de Calcio/química , Dióxido de Carbono/química , Sporosarcina/fisiología , Contaminación del Aire/prevención & control , Secuestro de Carbono , Precipitación Química
19.
Biofouling ; 29(6): 715-33, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23802871

RESUMEN

Microbially-induced calcium carbonate (CaCO3) precipitation (MICP) is a widely explored and promising technology for use in various engineering applications. In this review, CaCO3 precipitation induced via urea hydrolysis (ureolysis) is examined for improving construction materials, cementing porous media, hydraulic control, and remediating environmental concerns. The control of MICP is explored through the manipulation of three factors: (1) the ureolytic activity (of microorganisms), (2) the reaction and transport rates of substrates, and (3) the saturation conditions of carbonate minerals. Many combinations of these factors have been researched to spatially and temporally control precipitation. This review discusses how optimization of MICP is attempted for different engineering applications in an effort to highlight the key research and development questions necessary to move MICP technologies toward commercial scale applications.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Carbonato de Calcio/química , Precipitación Química , Materiales de Construcción/microbiología , Restauración y Remediación Ambiental/métodos , Urea/química , Ingeniería , Hidrólisis , Porosidad , Propiedades de Superficie
20.
Curr Opin Virol ; 58: 101289, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36584476

RESUMEN

Adult T-cell leukemia/lymphoma (ATLL) is an aggressive hematologic malignancy linked to HTLV-1 infection, which is refractory to therapy. The precise mechanism of oncogenesis in ATLL is incompletely understood, however, oncogenic viral genes Tax and Hbz are implicated, and recent large genomic and transcriptome studies provide further insight. Despite progress in understanding the disease, survival and outcome with current therapies remain poor. Long-term survivors are reported, primarily among those with indolent disease or activating CC chemokine receptor 4 mutations, however, allogeneic hematopoietic stem cell transplant is the only curative treatment option. The majority of patients succumb to their disease and ongoing and collaborative research efforts are needed. I will review recent updates in HTLV-1-associated ATLL epidemiology, pathogenesis, therapy, and prevention.


Asunto(s)
Infecciones por HTLV-I , Virus Linfotrópico T Tipo 1 Humano , Leucemia-Linfoma de Células T del Adulto , Linfoma , Adulto , Humanos , Virus Linfotrópico T Tipo 1 Humano/genética , Productos del Gen tax/genética
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