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1.
Rinsho Ketsueki ; 64(1): 35-41, 2023.
Artículo en Japonés | MEDLINE | ID: mdl-36775305

RESUMEN

Acquired hemophilia A (AHA) is a rare disease characteized by bleeding symptoms caused by decreased factor VIII activity due to the appearance of inhibitors to factor VIII triggered by malignancy or collagen disease. An 86-year-old woman developed purpura on her extremities after the first dose of the BNT162b2 mRNA COVID-19 vaccine. This symptom subsided after a few days. After the second dose of the BNT162b2 mRNA COVID-19 vaccine, purpura appeared again, and the patient was referred to our hospital Her APTT was remarkably prolonged to 110 seconds, and a cross-mixing test revealed an inhibitor pattern. Since FVIII activity was <1% and FVIII inhibitor was 51.6 BU, she was diagnosed with AHA. Prednisolone therapy was started, and coagulative complete remission was achieved. Because acquired hemophilia can develop after mRNA COVID-19 vaccination, as in this case, it is critical to monitor the appearance of bleeding symptom.


Asunto(s)
Vacuna BNT162 , COVID-19 , Hemofilia A , Anciano de 80 o más Años , Femenino , Humanos , Vacuna BNT162/efectos adversos , COVID-19/prevención & control , COVID-19/complicaciones , Hemofilia A/inducido químicamente , Hemofilia A/terapia , Hemorragia
2.
Biochem Biophys Res Commun ; 537: 118-124, 2021 01 22.
Artículo en Inglés | MEDLINE | ID: mdl-33388414

RESUMEN

Graft-versus-host disease (GVHD) is the most frequent complication after allogeneic hematopoietic stem cell transplantation (HSCT), and is one of the major causes of non-relapse mortality. Transferred mature lymphocytes are thought to be responsible for GVHD based on the findings that mice transplanted with lymphocyte-depleted bone marrow (BM) cells from MHC-mismatched donors do not develop GVHD. However, we found that overexpression of signal-transducing adaptor protein (STAP)-2 in lymphoid cells could induce GVHD after lymphocyte-depleted BM transplantation. To examine the function of STAP-2, which has been shown to play an important role in development and function of lymphocytes, in GVHD, we transplanted BM cells from STAP-2 deficient, or Lck promoter/IgH enhancer-driven STAP-2 transgenic (Tg) mice into MHC-mismatched recipients. Unexpectedly, mice transplanted with lymphocyte-depleted BM cells from STAP-2 Tg mice developed severe acute GVHD with extensive colitis and atrophy of thymus, while no obvious GVHD developed in mice transplanted with the wild type or STAP-2 deficient graft. Furthermore, mice transplanted with lymphocyte-depleted BM cells from the syngeneic STAP-2 Tg mice developed modest GVHD with colitis and atrophy of thymus. These results suggest that STAP-2 overexpression may enhance survival of allo-, and even auto-, reactive lymphocytes derived from engrafted hematopoietic progenitor cells in lethally irradiated mice, and that clarification of the mechanism may help understanding induction of immune tolerance after HSCT.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Células de la Médula Ósea/inmunología , Trasplante de Médula Ósea , Enfermedad Injerto contra Huésped/inmunología , Depleción Linfocítica , Enfermedad Aguda , Animales , Recuento de Linfocitos , Complejo Mayor de Histocompatibilidad , Ratones Transgénicos , Linfocitos T Reguladores/inmunología , Trasplante Homólogo
3.
Haematologica ; 106(2): 424-436, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-31974192

RESUMEN

Signal-transducing adaptor protein-2 (STAP-2) was discovered as a C-FMS/M-CSFR interacting protein and subsequently found to function as an adaptor of signaling or transcription factors. These include STAT5, MyD88 and IκB kinase in macrophages, mast cells, and T cells. There is additional information about roles for STAP-2 in several types of malignant diseases including chronic myeloid leukemia, however, none have been reported concerning B lineage lymphocytes. We have now exploited gene targeted and transgenic mice to address this lack of knowledge, and demonstrated that STAP-2 is not required under normal, steady-state conditions. However, recovery of B cells following transplantation was augmented in the absence of STAP-2. This appeared to be restricted to cells of B cell lineage with myeloid rebound noted as unremarkable. Furthermore, all hematological parameters were observed to be normal once recovery from transplantation was complete. Furthermore, overexpression of STAP-2, specifically in lymphoid cells, resulted in reduced numbers of late-stage B cell progenitors within the bone marrow. While numbers of mature peripheral B and T cells were unaffected, recovery from sub-lethal irradiation or transplantation was dramatically reduced. Lipopolysaccharide (LPS) normally suppresses B precursor expansion in response to interleukin 7, however, STAP-2 deficiency made these cells more resistant. Preliminary RNA-Seq analyses indicated multiple signaling pathways in B progenitors as STAP-2-dependent. These findings suggest that STAP-2 modulates formation of B lymphocytes in demand conditions. Further study of this adapter protein could reveal ways to speed recovery of humoral immunity following chemotherapy or transplantation.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales , Trasplante de Células Madre Hematopoyéticas , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Linfocitos B/metabolismo , Macrófagos/metabolismo , Ratones , Transducción de Señal
4.
Ann Hematol ; 99(9): 2133-2139, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32533251

RESUMEN

The overall outcome of patients with advanced-stage follicular lymphoma (FL) has improved significantly. However, some patients still develop multiple relapsed/refractory FL (RRFL). To address the still-limited data on this population, we performed this multi-center retrospective study. We analyzed 41 patients who received third-line treatment for RRFL at 8 institutes. The median age at diagnosis was 59 years (range, 38-70). The median progression-free survival (PFS) and probability of PFS at 2 years were 1.61 years and 39.4%, respectively, after third-line chemotherapy, and 0.45 years and 19.0%, respectively, after fourth-line chemotherapy. Objective response (OR) after third-line chemotherapy was achieved in 24 patients (53.7%). Bendamustine (Ben)-based regimens were associated with a significantly higher OR rate than other regimens (77.8% vs. 40.0%, respectively, P = 0.025). The median overall survival (OS) and probability of OS at 2 years were 4.71 years and 65.9%, respectively, after third-line chemotherapy, and 1.01 year and 45.1%, respectively, after fourth-line chemotherapy. In conclusion, this study had a small sample size and retrospective design, but it was able to demonstrate poor response rate and duration in patients with multiple RRFL, particularly after fourth-line chemotherapy. The optimal treatment strategy in this population should be clarified, including possibly hematopoietic stem cell transplantation.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Linfoma Folicular/diagnóstico , Linfoma Folicular/tratamiento farmacológico , Recurrencia Local de Neoplasia/diagnóstico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Adulto , Anciano , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Linfoma Folicular/mortalidad , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Estudios Retrospectivos , Tasa de Supervivencia/tendencias
5.
Database (Oxford) ; 20232023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-38506570

RESUMEN

Global activities involving the collection of marine biodiversity information have provided a large amount of biological observation records that cover various spatiotemporal areas. To predict biological responses or distribution changes in response to environmental changes by using these observation records, it is essential to analyze not only the current marine physicochemical environmental conditions but also the past conditions when the organisms were observed. We developed a new function to estimate the past marine environmental conditions for the observation records in our marine biodiversity database (Biological Information System for Marine Life: BISMaL) and examine whether the database can reliably estimate thermal habitats for both benthic and planktonic marine organisms. For the benthic squat lobster Shinkaia crosnieri, the estimated and observed in situ temperatures were similar to each other. For the planktonic chaetognaths Krohnitta pacifica and K. subtilis, the estimated temperatures showed clear seasonal changes specific to their distribution areas. These results indicated that BISMaL can reliably provide past habitat conditions regardless of planktonic or benthic lifestyles. BISMaL, which provides both biological observations and estimated past environmental conditions through web services, could lower the barrier to data access and use and make data-driven science available not only for data scientists but also for various marine scientists, such as taxonomists, ecologists and field scientists. Database URL:  https://www.godac.jamstec.go.jp/bismal/e/.


Asunto(s)
Biodiversidad , Bases de Datos Factuales
6.
Int J Hematol ; 114(1): 53-64, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33765256

RESUMEN

Post-transplant lymphoproliferative disorder (PTLD) is a life-threatening complication of transplantation. In addition to reactivation of Epstein-Barr virus in immunocompromised patients, impaired tumor immunity is suggested to be a risk factor for PTLD. However, it remains unclear whether immune suppressive tumor-infiltrating lymphocytes (TILs) correlate with the occurrence or prognosis of PTLD. We analyzed TILs in 26 patients with PTLD to elucidate the clinicopathological significance of the expression of PD-1 and FoxP3, which are associated with exhausted T-cells and regulatory T-cells (Tregs), respectively. Numbers of PD-1+ TILs in the PTLD specimens were significantly higher in patients who developed PTLD early after transplantation (P = 0.0040), while numbers of FoxP3+ TILs were not (P = 0.184). There was no difference in overall response rate regardless of the expression of PD-1 or FoxP3. FoxP3high patients tended to have a shorter time to progression compared with FoxP3low patients, especially in the case of FoxP3high patients with diffuse large B-cell lymphoma-subtype PTLD (P = 0.011), while PD-1high patients did not. These results suggest that T-cell exhaustion may be mainly associated with PTLD development, while immune suppression by Tregs may be dominant in enhanced progression of PTLD following disease occurrence.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas/efectos adversos , Linfocitos Infiltrantes de Tumor/patología , Trastornos Linfoproliferativos/etiología , Trasplante de Órganos/efectos adversos , Receptor de Muerte Celular Programada 1/análisis , Adulto , Anciano , Femenino , Factores de Transcripción Forkhead/análisis , Humanos , Linfoma de Células B Grandes Difuso/patología , Linfoma de Células B Grandes Difuso/terapia , Trastornos Linfoproliferativos/patología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
7.
Int J Dent ; 2020: 7316796, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32774376

RESUMEN

BACKGROUND: In Japan's super-aging society, it is required to establish a home dental service provision system. It is necessary to analyze the current state of visiting dentistry. METHODS: A cross-sectional survey was conducted using a self-administered postal mail questionnaire distributed to all members of the Iwate Dental Association. We analyzed the implementation status of dental care at home/nursing facilities, the number of dental clinic staff, and the contents of dental home care. Correspondence analysis, item response theory, and zero-inflated model were used for the analysis. RESULTS: Of the 354 dental clinics, 187 (52.8%) performed visiting dental care and 195 (55.1%) implemented dental care in a nursing home. Visit dentistry was mainly performed by part-time workers. Denture treatment and oral care were common treatments for dental home care. CONCLUSION: More than half of the dental clinics did not offer visiting dentistry. In order to fully provide dental visiting services, infrastructure development is necessary. Specifically, human resources are most important, even if they are part-time workers.

8.
Oncogene ; 39(34): 5601-5615, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32661325

RESUMEN

The family of signal-transducing adapter proteins (STAPs) has been reported to be involved in a variety of intracellular signaling pathways and implicated as transcriptional factors. We previously cloned STAP-2 as a c-Fms interacting protein and explored its effects on chronic myeloid leukemia (CML) leukemogenesis. STAP-2 binds to BCR-ABL, upregulates BCR-ABL phosphorylation, and activates its downstream molecules. In this study, we evaluated the role of STAP-1, another member of the STAP family, in CML pathogenesis. We found that the expression of STAP-1 is aberrantly upregulated in CML stem cells (LSCs) in patients' bone marrow. Using experimental model mice, deletion of STAP-1 prolonged the survival of CML mice with inducing apoptosis of LSCs. The impaired phosphorylation status of STAT5 by STAP-1 ablation leads to downregulation of antiapoptotic genes, Bcl-2 and Bcl-xL. Interestingly, transcriptome analyses indicated that STAP-1 affects several signaling pathways related to BCR-ABL, JAK2, and PPARγ. This adapter protein directly binds to not only BCR-ABL, but also STAT5 proteins, showing synergistic effects of STAP-1 inhibition and BCR-ABL or JAK2 tyrosine kinase inhibition. Our results identified STAP-1 as a regulator of CML LSCs and suggested it to be a potential therapeutic target for CML.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Apoptosis/genética , Modelos Animales de Enfermedad , Regulación Leucémica de la Expresión Génica , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Células Madre Neoplásicas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Línea Celular Tumoral , Proteínas de Fusión bcr-abl/genética , Proteínas de Fusión bcr-abl/metabolismo , Perfilación de la Expresión Génica/métodos , Humanos , Células K562 , Estimación de Kaplan-Meier , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Ratones Endogámicos C57BL , Ratones Noqueados , Células Madre Neoplásicas/patología , Unión Proteica , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transducción de Señal/genética
9.
Chem Commun (Camb) ; (8): 819-21, 2007 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-17308642

RESUMEN

Photoisomerization of encapsulated Z-enecarbamates within the hydrophobic chiral cavities of gamma-CD showed higher diastereoselectivities in the photoproducts than those obtained in solution. The selective encapsulation of the enecarbamates and the following isomerization process are both diastereoselectively controlled by gamma-CD.


Asunto(s)
Alquenos/química , Carbamatos/química , Oxazolidinonas/química , Dicroismo Circular , Indicadores y Reactivos , Isomerismo , Espectroscopía de Resonancia Magnética , Fotoquímica , Soluciones , Estereoisomerismo
10.
Org Lett ; 8(9): 1909-12, 2006 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-16623582

RESUMEN

[reaction: see text] Diastereodifferentiating [2+2] photocycloadditions of (E)- and (Z)-stilbenes to bis((R)-1-methylpropyl) fumarate were performed through the direct excitation of stilbenes and the selective excitation of the charge-transfer (CT) complex at various temperatures. The geometrical isomers of stilbene afforded the opposite diastereomers of mu-truxinate in both excitation modes, with a dramatic decrease in the product's diastereoselectivity upon prolonged irradiations.

11.
Photochem Photobiol ; 82(1): 123-31, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16076247

RESUMEN

On photooxygenation of the optically active Z/E enecarbamates 1 (X = i-Pr) and 2 (X = Me) equipped with the oxazolidinone chiral auxiliary in methylene-blue (MB)-incorporated, alkali-metal (M = Li, Na, K, Cs, Rb), exchanged Y-type zeolites (MY-MB), oxidative cleavage of the alkenyl functionality releases the enantiomerically enriched methyldesoxybenzoin (MDB) product. The extent (%ee) and/or the sense (R or S) of the stereoselectivity in the formation of the MDB product depends on the choice of the alkyl substiuent (i-Pr or Me) at the C-4 position of the oxazolidinone chiral auxiliary, the Z/E configuration of the alkene functionality in the enecarbamates, and the type of alkali metal in the zeolite. Most significantly-the highlight of this study-is the reversed sense (R or S) in the stereoselection when the photooxygenation is run in CDCl3 solution versus inside the MY-MB zeolite. As a mechanistic rationale for this novel stereochemical behavior, we propose the combined action of spatial confinement and metal-ion coordination (assessed by density-functional calculations) of the substrate within the zeolite supercage, both of which greatly reduce the freedom of the substrate and entropically manipulate the stereochemical outcome.

12.
JPEN J Parenter Enteral Nutr ; 30(3): 179-85, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16639063

RESUMEN

BACKGROUND: Early enteral nutrition is associated with a lower incidence of intraabdominal abscess in severely injured patients than parenteral nutrition (PN). We explored the underlying mechanisms by examining the influence of nutrition route on nuclear factor kappaB (NFkappaB) activation in peritoneal exudative cells (PECs) and peritoneal cytokine levels. METHODS: Thirty male Institute Cancer Research mice were randomized to chow (n = 10), IV PN (n = 10), or intragastric (IG) PN (n = 10) and fed for 5 days. PECs were harvested at 2 or 4 hours after intraperitoneal injection of 2 mL of 1% glycogen. Intranuclear NFkappaB activity in PECs was examined by laser scanning cytometry. Cytokine (tumor necrosis factor-alpha [TNF-alpha], macrophage inflammatory protein-2 [MIP-2], interleukin-10 [IL-10]) levels in peritoneal lavaged fluid were determined by enzyme-linked immunosorbent assay. RESULTS: Intranuclear NFkappaB at 2 hours was significantly higher in the chow and IG-PN groups than in the IV-PN group. TNF-alpha and IL-10 levels of the chow group were significantly higher than those of IV-PN mice at 2 hours, whereas those of IG-PN mice were midway between those of the chow and IV-PN groups. MIP-2 was significantly higher in the chow group than in the IG-PN and IV-PN mice at 2 hours. TNF-alpha levels correlated positively with intranuclear NFkappaB activity in PECs. CONCLUSIONS: Enteral nutrition may improve peritoneal defense by preserving early NFkappaB activation in PECs and cytokine responses.


Asunto(s)
Citocinas/metabolismo , Glucógeno/farmacología , FN-kappa B/metabolismo , Nutrición Parenteral , Cavidad Peritoneal/citología , Peritonitis/inmunología , Animales , Quimiocina CXCL2 , Modelos Animales de Enfermedad , Vías de Administración de Medicamentos , Nutrición Enteral , Interleucina-10/metabolismo , Citometría de Barrido por Láser/métodos , Masculino , Ratones , Ratones Endogámicos ICR , Monocinas/metabolismo , Nutrición Parenteral/efectos adversos , Peritonitis/inducido químicamente , Distribución Aleatoria , Organismos Libres de Patógenos Específicos , Factor de Necrosis Tumoral alfa/metabolismo
13.
Shock ; 24(4): 382-7, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16205325

RESUMEN

Morbidity of intra-abdominal abscess is increased when severely injured patients are fed parenterally. Lack of enteral nutrition appears to impair peritoneal cavity host defense. Because the transcription factor nuclear factor kappaB (NFkappaB) regulates various genes involved in inflammatory responses and its activation is important for host defense, we hypothesized that enteral nutrition would preserve appropriate NFkappaB activation in peritoneal resident cells (PRCs), the first defense line against peritoneal contamination. Mice (n = 105) were randomized to chow (n = 38), intravenous (IV)-total parenteral nutrition (TPN) (n = 34), or intragastric (IG)-TPN (n = 33) for 5 days' feeding. In experiment 1, PRCs were harvested for measurement of intranuclear NFkappaB activity with or without in vitro lipopolysaccharide (LPS) stimulation using laser scanning cytometry and enzyme-linked immunoabsorbant assay. PRC numbers tended to be higher in enterally fed mice than in IV-TPN mice. The main PRC subpopulation was macrophages in all groups. NFkappaB activation was increased in response to LPS in chow mice, whereas there was no increase in the IV-TPN group. IG-TPN mice demonstrated moderate NFkappaB activation. In experiment 2, mice underwent cecal ligation and puncture (CLP). Survival was observed up to 5 days. In another set of mice, tumor necrosis factor (TNF) alpha levels of peritoneal lavaged fluid were measured 4 h after CLP. Survival times after CLP improved in the chow and IG-TPN groups compared with the IV-TPN group. TNFalpha levels were significantly higher in the chow than in the IV-TPN group. In conclusion, parenteral nutrition decreases PRC number and blunts NFkappaB activation in PRCs. These changes may impair host defense in the peritoneal cavity.


Asunto(s)
FN-kappa B/metabolismo , Peritoneo/patología , Transporte Activo de Núcleo Celular , Aminoácidos/química , Animales , Peso Corporal , Citoplasma/metabolismo , Relación Dosis-Respuesta a Droga , Ensayo de Inmunoadsorción Enzimática , Inflamación , Rayos Láser , Lipopolisacáridos/química , Lipopolisacáridos/metabolismo , Macrófagos/metabolismo , Ratones , Microscopía Fluorescente , Peritoneo/inmunología , Transporte de Proteínas , Sepsis , Factores de Tiempo , Factor de Necrosis Tumoral alfa/metabolismo , Cicatrización de Heridas
14.
Org Lett ; 7(11): 2089-92, 2005 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-15901141

RESUMEN

[reaction: see text]. Oxazolidinone-functionalized enecarbamates show contrasting behavior upon oxidation by singlet oxygen and by ozone. The observed stereoselectivity difference indicates that the oxidation with ozone is subject to classic steric effects, whereas the very high selectivity in the photooxidation with singlet oxygen is derived from vibrational deactivation.

15.
Chem Commun (Camb) ; (27): 3424-6, 2005 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-15997285

RESUMEN

Oxazolidinone-functionalized enecarbamates undergo diastereoselective E/Z photoisomerization upon direct and triplet sensitized irradiations with chiral/achiral sensitizers, showing that the enhanced product diastereoselectivity depends on the solvent and temperature.

16.
Shock ; 19(3): 238-44, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12630523

RESUMEN

Tyrosine phosphorylation plays a critical role in signal transduction pathways in immune cells. Laser scanning cytometer (LSC), a newly developed microscope-based cytofluorometer, may overcome shortcomings of Western blotting and flow cytometry in the detection of intracellular signaling transduction. The aims of this study were to visualize and quantitate intracellular phosphotyrosine in the peritoneal cells harvested from diet-restricted mice by LSC. In addition, using LSC, we identified the main cell type with activated tyrosine phosphorylation in response to an inflammatory stimulus and we investigated the intracellular distribution of tyrosine phosphorylation within the peritoneal macrophages. Mice were assigned to the ad libitum and diet-restricted, i.e., 75% restricted food intake, groups. After 7 days of pair feeding, the peritoneal cells were harvested. Tyrosine phosphorylation in the harvested cells with either N-formyl-methionyl-leucyle-phenylalanine (fMLP) or lipopolysaccharide (LPS) stimulation was examined using LSC. Tyrosine phosphorylation of peritoneal cells from the diet-restricted group was significantly higher than that from the ad libitum group, regardless of stimulation. Stimulation of peritoneal cells with either fMLP or LPS significantly increased tyrosine phosphorylation in the ad libitum group, but not in the diet-restricted group. The relocation feature of LSC revealed that the cells with distinct tyrosine phosphorylation were macrophages. Topographic analysis demonstrated that phosphotyrosine was localized mainly in the cytoplasm of these cells. In summary, LSC revealed that tyrosine phosphorylation is mainly in the cytoplasm of the peritoneal macrophages and is deranged by diet restriction. LSC is a powerful tool for the study of intracellular signaling transduction.


Asunto(s)
Dieta Reductora , Macrófagos Peritoneales/citología , Macrófagos Peritoneales/fisiología , Fosfoproteínas/metabolismo , Animales , Peso Corporal , Ingestión de Energía , Rayos Láser , Masculino , Ratones , Ratones Endogámicos ICR , N-Formilmetionina Leucil-Fenilalanina/farmacología , Fosforilación
17.
Shock ; 19(6): 497-502, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12785002

RESUMEN

Appropriate polymorphonuclear neutrophil (PMN) recruitment is essential for host defense against infection. We investigated the significance of the preoperative PMN adhesion-migration process, as assessed by the flow chamber method, on postoperative infectious complications. Thirty-one consecutive patients with gastrointestinal malignancies, 21 colorectal and 10 gastric, who were undergoing elective surgery were enrolled. PMNs, isolated preoperatively from each patient's venous blood, were perfused onto a tumor necrosis factor alpha-stimulated human umbilical vein endothelial cell (HUVEC) monolayer through the flow chamber. We evaluated the adherent PMN number, the migrated PMN number, and the stuck PMN number by directly inspecting PMN interactions with a HUVEC monolayer under continuous shear flow simulating postcapillary venules. The expression of adhesion molecules on circulating PMNs was also measured. Patients were grouped into an infectious and a noninfectious group according to the occurrence of postoperative infectious complications defined by the Centers for Disease Control criteria. Eleven patients developed postoperative infectious complications. Although the number of preoperative in vitro adherent PMNs in patients with postoperative infection was significantly higher than in those without postoperative infection (P = 0.01), migrated PMN number was similar in both groups. Stuck PMN number tended to be higher in the infectious group than in the noninfectious group. The migrated PMN number showed a significant positive correlation with the adherent PMN number in the noninfectious group but not in the infectious group. Preoperative CD31 expression on circulating PMNs was significantly lower in the infectious group than in the noninfectious group. Preoperative in vitro derangement of the PMN adhesion-migration process is closely associated with postoperative infectious complications.


Asunto(s)
Infecciones/sangre , Neutrófilos/fisiología , Complicaciones Posoperatorias/sangre , Infección de la Herida Quirúrgica/sangre , Anciano , Adhesión Celular/fisiología , Línea Celular , Colectomía , Endotelio Vascular/citología , Femenino , Gastrectomía , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Análisis Multivariante , Neoplasias/cirugía , Neutrófilos/patología , Complicaciones Posoperatorias/epidemiología , Cuidados Preoperatorios , Recto/cirugía , Factores de Riesgo , Infección de la Herida Quirúrgica/epidemiología , Venas Umbilicales
18.
Shock ; 18(1): 69-74, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12095137

RESUMEN

Antibiotic therapy is an essential treatment for gram-negative bacterial infections. Antibiotic-induced endotoxin release and subsequent production of inflammatory cytokines reportedly depend on the type of antibiotic action. This study examined the effects of various beta-lactam antibiotics on cell death of human polymorphonuclear neutrophils (PMNs) cocultured with Escherichia coli (E. coli) in vitro. E. coli morphology after antibiotic treatment was determined. PMNs and E. coli were cocultured with antibiotics for 0, 4, or 12 h. Levels of endotoxin and cytokines (TNF-alpha, IL-1beta, and IL-6) in the supernatants were measured. The filtrates of antibiotic-treated E. coli supernatants were cocultured with PMNs for 0, 4, or 12 h. In all experiments, ampicillin (ABPC), cefazolin sodium (CEZ), cefoperazone sodium (CPZ), latamoxef sodium (LMOX), imipenem (IPM), and polymyxin B sulfate (PLB) were used at 30 microg/mL. PMNs were isolated from healthy volunteers. PMN cell death was assessed by flow cytometry and light microscopy. ABPC, CEZ, CPZ, and LMOX, which induce bacterial filament formation with lysis, caused PMN necrosis when cocultured with E. coli. In contrast, IPM, which induces bacterial spheroplast formation with lysis, caused PMN apoptosis. Levels of endotoxin, TNF-alpha and IL-6 in the supernatants with IPM and PLB were significantly lower than in those with other beta-lactam antibiotics. The filtrates of IPM- and PLB-treated E. coli supernatants induced PMN apoptosis, whereas those treated with other beta-lactam antibiotics increased PMN necrosis. Beta-lactam antibiotics have different impacts on the types of PMN cell death after E. coli killing. Underlying mechanisms and the clinical relevance of IPM-induced PMN apoptosis in severe gram-negative infection warrant further investigation.


Asunto(s)
Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Neutrófilos/efectos de los fármacos , Neutrófilos/microbiología , Muerte Celular/efectos de los fármacos , Células Cultivadas , Técnicas de Cocultivo , Medios de Cultivo , Medios de Cultivo Condicionados/farmacología , Citocinas/metabolismo , Endotoxinas/metabolismo , Escherichia coli/metabolismo , Humanos , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Neutrófilos/citología , Factor de Necrosis Tumoral alfa/metabolismo , beta-Lactamas
19.
Chem Commun (Camb) ; (18): 2302-3, 2003 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-14518885

RESUMEN

The photodecarboxylation of chiral mesityl alkanoate to mesitylalkane has been studied experimentally/theoretically, and it has been found that the photodecarboxylation proceeds to give the product in > 99% enantiomeric excesses under a variety of conditions, indicating no involvement of any radical intermediates, but that the reaction proceeds through the concerted cheletropic extrusion of CO2 from the energetically less-favored s-cis conformation.

20.
Chem Commun (Camb) ; (14): 1652-3, 2004 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-15263963

RESUMEN

The geometry (donor-acceptor distance) and association constant of the ground-state CT complex were considerably affected by applied pressure, thus enhancing the reaction rate and the adduct yield particularly upon CT excitation, but the diastereoselectivity did not show any substantial change at elevated pressures in both excitation modes.

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