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1.
Cancer Med ; 13(12): e7430, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38924675

RESUMEN

AIM: Atezolizumab and bevacizumab (Atezo/Bev) combination immunotherapy regimens and direct oral anticoagulants (DOACs) are both associated with bleeding. Therefore, combining Atezo/Bev regimens with DOACs may exacerbate the bleeding risk. This study investigated the feasibility of the Atezo/Bev regimen in patients taking DOACs. METHODS: This retrospective study included 141 patients with unresectable hepatocellular carcinoma (HCC) or advanced lung cancer (LC) treated with Atezo/Bev regimens. Patients who used antithrombotic agents other than DOACs were excluded. Bleeding events during the Atezo/Bev regimen were analyzed. RESULTS: The incidence rates of bleeding of any grade in the DOAC (n = 11) and no antithrombotic agent (NAA) (n = 130) groups were 9.1% and 10.8%, respectively, with no significant differences. Moreover, no significant difference was found in the frequency of bleeding of grade ≥3 between the DOAC and NAA groups. No patients in the DOAC group discontinued the Atezo/Bev regimen because of severe bleeding. Although serum albumin levels, with a hazard ratio (HR) of 0.298 (95% confidence interval [CI]: 0.105-0.847), independently contributed to bleeding events (p = 0.023), DOAC administration did not (HR: 1.357; 95% CI: 0.157-10.54; p = 0.770). Among only patients with HCC (n = 59), none of the five patients taking DOACs experienced bleeding events. A high albumin-bilirubin score (HR: 9.083, 95% CI: 1.118-73.76) was associated with bleeding events (p = 0.039). CONCLUSIONS: DOACs did not have a considerable effect on bleeding events in the Atezo/Bev regimens for HCC or LC. Under careful surveillance for bleeding, Atezo/Bev regimens may be feasible in patients receiving DOACs.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Bevacizumab , Carcinoma Hepatocelular , Estudios de Factibilidad , Hemorragia , Neoplasias Hepáticas , Neoplasias Pulmonares , Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Masculino , Neoplasias Hepáticas/tratamiento farmacológico , Femenino , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/uso terapéutico , Estudios Retrospectivos , Neoplasias Pulmonares/tratamiento farmacológico , Anciano , Persona de Mediana Edad , Hemorragia/inducido químicamente , Bevacizumab/administración & dosificación , Bevacizumab/efectos adversos , Bevacizumab/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Anticoagulantes/administración & dosificación , Anticoagulantes/efectos adversos , Anticoagulantes/uso terapéutico , Administración Oral , Anciano de 80 o más Años
2.
Auris Nasus Larynx ; 51(1): 221-229, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37532644

RESUMEN

OBJECTIVE: A phosphorylcholine (PC)-derivative with high binding ability (PCDB) was intranasally administered to mice with ovalbumin (OVA), and immune responses were investigated to determine whether PCDB has antigenicity and adjuvanticity. METHODS: BALB/c mice were intranasally immunized with PCDB coupled with OVA, unbound PCDB plus OVA, cholera toxin (CT) plus OVA, OVA alone, and PCDB alone. Then, the production of OVA- and PC-specific antibodies in external secretions and serum, and the secretion of cytokines such as IL-4 and IFN-γ from splenic mononuclear cells by stimulation with PCDB and OVA were examined. Furthermore, the secretion of IL-12p40 from CD11c+ cells following stimulation with PCDB was observed to clarify the adjuvant effect of PCDB through TLR4. RESULTS: Intranasal immunization with PCDB plus OVA increased OVA- and PC-specific IgA in external secretions and OVA- and PC-specific antibodies in the serum. The analysis of IgG subclasses specific to OVA and PC showed a higher production of IgG1 than IgG2, and the secretion of both IL-4 and IFN-γ was enhanced. However, IL-12p40 secretion from CD11c+ cells was increased and OVA-specific IgE production was not promoted by PCDB stimulation. CONCLUSION: Intranasal administration of the protein antigen with PCDB enhanced immune responses specific to the mixed antigen and PC. Although PCDB acted to bias the immune response toward the Th2-type, antigen-specific IgE production did not increase. These findings suggest that PCDB has the potential to be a mucosal vaccine with both adjuvanticity and antigenicity without causing side effects due to type I allergy.


Asunto(s)
Inmunidad Mucosa , Fosforilcolina , Ratones , Animales , Subunidad p40 de la Interleucina-12/farmacología , Interleucina-4 , Adyuvantes Inmunológicos/farmacología , Toxina del Cólera/farmacología , Administración Intranasal , Nariz , Inmunoglobulina G , Inmunoglobulina E , Ratones Endogámicos BALB C
3.
J Oral Microbiol ; 12(1): 1808425, 2020 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-33062198

RESUMEN

OBJECTIVE: We aimed to investigate the inhibitory effect of 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer on the adherence of Streptococcus pneumoniae (Spn) and nontypeable Haemophilus influenzae (NTHi) in vitro and in vivo. MATERIALS AND METHODS: Phosphorylcholine (PC) expression of 21 strains each of Spn and NTHi was evaluated using fluorescence-activated cell sorting; the adherence of bacteria to Detroit 562 cells and to the nasal mucosa of BALB/c mice was determined. MPC polymer-mediated inhibitory effects were compared with PC-keyhole limpet hemocyanin (PC-KLH)-mediated inhibitory effects. RESULTS: In vitro experiments showed that pretreatment with MPC polymer markedly inhibited the adherence of Spn and NTHi in a concentration dose-dependent manner independently of PC expression. No correlation was observed between PC expression and MPC polymer-mediated inhibitory effects. Contrarily, there was a significant negative correlation between PC-KLH-mediated inhibitory effects and PC expression in Spn and NTHi. The same results were obtained via in vivo experiments. The MPC polymer did not affect the histology of the nasal mucosa. CONCLUSIONS: MPC polymer might be effective to reduce the occurrence of upper respiratory tract infection caused by Spn and NTHi and could be applied for the development of local treatments, such as topical gargles and nebulizer medications.

4.
Auris Nasus Larynx ; 47(6): 1023-1026, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32690229

RESUMEN

OBJECTIVE: To investigate the incidence of acute epiglottitis (AE) and the clinical features of patients with AE complicated by peritonsillar abscess (PTA), considering that PTA, especially inferior-type PTA, is often a comorbidity of AE. METHODS: We retrospectively reviewed the medical records of patients who were diagnosed as having AE by otolaryngologists and referred to our hospital between January 2009 and December 2017. All the patients underwent laryngeal endoscopy and contrast-enhanced computed tomography (CT) for examination of the severity of AE and its complications by other infections, including PTA. The clinical characteristics of patients with PTA were compared with those of patients without PTA. RESULTS: A total of 139 patients were enrolled, of whom 21 (15%) were found to have PTA. Among the 21 patients, only one had a superior-type PTA and the others had an inferior-type PTA. The patients with complicated AE by an inferior Cap-type PTA frequently showed unilateral arytenoid swelling. CONCLUSION: PTA is a comorbidity of AE, and unilateral arytenoid swelling is considered to suggest the presence of inferior-type PTA.


Asunto(s)
Epiglotitis/complicaciones , Absceso Peritonsilar/complicaciones , Enfermedad Aguda , Adulto , Cartílago Aritenoides/diagnóstico por imagen , Cartílago Aritenoides/patología , Endoscopía , Epiglotitis/diagnóstico , Femenino , Humanos , Masculino , Absceso Peritonsilar/diagnóstico , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
5.
Auris Nasus Larynx ; 47(3): 477-480, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30962015

RESUMEN

Malignancies have been reported to occasionally arise in scar tissue following injury. One hypothesis involves prolonged overactivation of tissue repair systems due to chronic inflammation and irritation, although the pathogenesis of cancers occurring in scars is not fully understood. We describe here two cases with a history of maxillary fracture at the site where squamous cell carcinoma (SCC) subsequently developed. The first patient developed SCC 7 years after right maxillary fractures resulting from a traffic accident. He underwent chemoradiotherapy (70 Gy in 35 fractions) and maintained complete response (CR) for 10 months. The second patient developed SCC 3 years after sustaining right maxillary fractures in an ice hockey game. Radiotherapy and total maxillectomy were performed, but local recurrence arose and he has since been receiving chemotherapy.


Asunto(s)
Carcinoma de Células Escamosas/etiología , Fracturas Maxilares/complicaciones , Neoplasias Maxilares/etiología , Adulto , Anciano , Carcinoma de Células Escamosas/diagnóstico por imagen , Carcinoma de Células Escamosas/terapia , Quimioradioterapia , Humanos , Imagen por Resonancia Magnética , Masculino , Maxilar/cirugía , Neoplasias Maxilares/diagnóstico por imagen , Neoplasias Maxilares/terapia , Persona de Mediana Edad , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/cirugía , Radioterapia
6.
Arch Iran Med ; 21(1): 41-43, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29664669

RESUMEN

Primary nonsecretory plasma cell leukemia (PCL) is an extremely rare type of multiple myeloma. Here, we report a case of nonsecretory PCL with no previous history of multiple myeloma. The case exhibited extremely low levels of serum immunoglobulin and light chain, no detectable serum M-protein or free light chain restriction, no urine BJP, and no cytoplasmic light chain expression in flow cytometry. In fluorescence in situ hybridization, tumor cells exhibited fusion genes for IgH/BCL1 and IgH/cMyc, disappearance of the p53 signal, and a split signal for IgK(2p11), but no split signal for IgL (22q11). Therefore, we diagnosed primary nonsecretory PCL with multiple chromosomal abnormalities.


Asunto(s)
Reordenamiento Génico , Leucemia de Células Plasmáticas/genética , Translocación Genética , Anciano , Femenino , Humanos , Cadenas Ligeras de Inmunoglobulina/sangre , Hibridación Fluorescente in Situ , Leucemia de Células Plasmáticas/sangre , Leucemia de Células Plasmáticas/patología , Proteínas de Mieloma/metabolismo
7.
Laryngoscope ; 128(3): E91-E96, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29226330

RESUMEN

OBJECTIVE: Pneumococcal infection caused by Streptococcus pneumoniae is a major upper respiratory tract disease that causes severe illness and mortality. Therefore, it is important to develop safe and effective vaccines to prevent pneumococcal infections. The goal of the study was to investigate the effectiveness of transcutaneous immunization (TCI) for induction of pneumococcal surface protein A (PspA) responses in the upper respiratory tract. METHODS: C57BL/6 mice were transcutaneously immunized with 1 µg of PspA and 2 µg of cholera toxin (CT) six times at weekly intervals and compared with transcutaneously treated controls (PBS alone/PspA alone/CT alone). Two weeks after the final immunization, nasal washes (NWs), saliva, and plasma samples were collected and subjected to a PspA-specific ELISA. Three weeks after the final immunization, mice were challenged with S. pneumoniae strain EF3030, and the numbers of CFUs in NWs and nasal passages (NPs) were determined. RESULTS: Higher levels of PspA-specific IgM, IgG, and IgA Abs were noted in plasma of TCI with PspA plus CT compared with controls. Transcutaneous immunization mice also had significantly increased PspA-specific S-IgA Ab responses in NWs and saliva and, importantly, showed significantly lower numbers of bacteria CFUs in NWs and NPs compared with controls. CONCLUSION: These results show that TCI with PspA plus CT induces antigen-specific mucosal and systemic immune responses. This suggests that this method is an effective mucosal immunization strategy for induction of protective pneumococcal-specific Ab responses in blockade of S. pneumoniae colonization of the nasal cavity. LEVEL OF EVIDENCE: NA. Laryngoscope, 128:E91-E96, 2018.


Asunto(s)
Proteínas Bacterianas/inmunología , Inmunización/métodos , Infecciones Neumocócicas/prevención & control , Vacunas Neumococicas/inmunología , Streptococcus pneumoniae/inmunología , Animales , Proteínas Bacterianas/sangre , Toxina del Cólera , Femenino , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Ratones , Ratones Endogámicos C57BL , Vacunas Neumococicas/administración & dosificación
8.
Int Immunol ; 29(1): 5-10, 2017 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-28391291

RESUMEN

Age-associated alterations in the mucosal immune system are generally termed mucosal immunosenescence. The major change seen in the aged mucosa is a failure to elicit an antigen-specific secretory IgA (SIgA) antibody response, which is a central player for host defense from various pathogens at mucosal surfaces. In this regard, it would be a first priority to compensate for mucosal dysregulation in the elderly in order to maintain their health in aging. We have successfully established antigen-specific SIgA antibody responses in aged (2 years old) mice, which provide protective immunity from Streptococcus pneumoniae and influenza virus infections, by using a new adjuvant system consisting of a plasmid encoding Flt3 ligand (pFL) and CpG ODN. In order to explore possible use of current mucosal vaccine strategies for the elderly, we have adoptively transferred adipose tissue-derived mesenchymal stem cells (AMSCs) to aged mice prior to mucosal vaccination. This immune therapy successfully resulted in protective antigen-specific antibody responses in the intestinal mucosa of aged mice that were comparable to those seen in young adult mice. In this regard, we postulate that adoptively transferred AMSCs could augment dendritic cell functions in aged mice. The potential cellular and molecular mechanisms whereby AMSCs restore mucosal immunity in immunosenescence are discussed in this short review. A stem cell transfer system could be an attractive and effective immunologic intervention strategy to reverse mucosal immunosenescence.


Asunto(s)
Tejido Adiposo/inmunología , Envejecimiento/inmunología , Inmunidad Mucosa/inmunología , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/inmunología , Infecciones Neumocócicas/terapia , Streptococcus pneumoniae/inmunología , Envejecimiento/patología , Animales , Humanos , Ratones , Infecciones Neumocócicas/inmunología , Infecciones Neumocócicas/patología
9.
Auris Nasus Larynx ; 43(6): 685-8, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26946996

RESUMEN

OBJECTIVE: To better understand the causes of the exacerbation of rhinitis medicamentosa (RM) induced by oxymetazoline (OMZ) or benzalkonium chloride (BKC), we examined the impact of pretreatment with OMZ or BKC on cultured human nasal epithelial cells. We also examined the effect of mometasone furoate (MF) on the cultured human nasal epithelial cells treated with OMZ or BKC. METHODS: Cells of the human nasal epithelial cell line HNEpC were treated with OMZ or BKC, and the OMZ- and BKC-induced expression of histamine H1 receptor (H1R) mRNA was assayed using real-time polymerase chain reaction. In some experiments, 1.0×10(-5)M MF was added to the HNEpC cells for 24h before treatment with OMZ or BKC. RESULTS: Treatment with OMZ slightly increased the expression level of H1R mRNA in HNEpC cells. This enhanced expression was not significantly reduced by pretreatment with MF. In contrast, treatment with BKC remarkably increased the expression level of H1R mRNA in HNEpC cells. In addition, this enhanced expression was significantly reduced by pretreatment with MF. CONCLUSION: These results suggest that the increased expression of H1R mRNA due to treatment with OMZ or BKC might be one of the factors underlying the exacerbation of symptoms in patients with RM and those complicated with allergic rhinitis. The concomitant use of a nasal steroid might reduce the exacerbation of symptoms caused by BKC, although there remains a risk of developing histamine hypersensitivity from the long-term use of a topical steroid-containing BKC.


Asunto(s)
Antiinfecciosos Locales/farmacología , Compuestos de Benzalconio/farmacología , Células Epiteliales/efectos de los fármacos , Descongestionantes Nasales/farmacología , Mucosa Nasal/efectos de los fármacos , Oximetazolina/farmacología , ARN Mensajero/efectos de los fármacos , Receptores Histamínicos H1/efectos de los fármacos , Línea Celular , Progresión de la Enfermedad , Células Epiteliales/metabolismo , Humanos , Mucosa Nasal/metabolismo , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores Histamínicos H1/genética , Rinitis Alérgica/genética , Rinitis Alérgica/metabolismo
10.
Auris Nasus Larynx ; 43(2): 182-6, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26527518

RESUMEN

OBJECTIVE: To clarify indications for immediate abscess tonsillectomy (IAT) for peritonsillar abscess (PTA). METHODS: A retrospective study was performed on 99 patients who were diagnosed with PTA on the basis of computed tomography (CT). Based on CT findings, PTA patients were classified into two categories by abscess shape: Oval type and Cap type. Furthermore, abscess location was differentiated into superior and inferior, resulting in a final classification of 4 categories: superior Oval type; superior Cap type; inferior Oval type; and inferior Cap type. In addition, the proportion of PTA patients showing extraperitonsillar spread into parapharyngeal spaces in each category was examined. RESULTS: Superior Oval-type PTA was the most common. Thirteen patients showed extraperitonsillar spread. When CT classifications were compared with clinical findings, patients with inferior Cap-type abscess displayed extraperitonsillar spread more frequently than the other categories of PTA. In all 13 patients, the parapharyngeal space was involved. In addition, 3 patients displayed retropharyngeal space involvement. In all 13 cases, abscess remained above the hyoid bone. CONCLUSIONS: Inferior Cap-type PTA may need more intensive and reliable treatment, such as IAT, which might be effective for PTA showing extraperitonsillar spread.


Asunto(s)
Absceso Peritonsilar/diagnóstico por imagen , Absceso Retrofaríngeo/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Humanos , Hueso Hioides/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Absceso Peritonsilar/clasificación , Absceso Peritonsilar/cirugía , Absceso Retrofaríngeo/clasificación , Absceso Retrofaríngeo/cirugía , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Tonsilectomía , Adulto Joven
12.
Laryngoscope ; 121(11): 2443-8, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21994002

RESUMEN

OBJECTIVES/HYPOTHESIS: Viral upper respiratory tract infections (URIs) are often followed by secondary bacterial infections. To better understand this phenomenon, we examined the impact of the viral agent polyinosine-polycytidylic acid [Poly (I:C)] on the adherence of Streptococcus pneumoniae (Spn) to pharyngeal epithelial cells. STUDY DESIGN: In vitro model of cultured human pharyngeal epithelial cells. METHODS: Detroit 562 cells, a human pharyngeal carcinoma cell line, were pretreated with Poly (I:C). Poly (I:C)-induced expression of platelet-activating factor receptor (PAF-R) was assayed using real-time polymerase chain reaction, flow cytometry, and immunofluorescence microscopy. Bacterial adhesion to these epithelial cells was assessed using immunofluorescence microscopy and colony formation assays. RESULTS: Pretreatment with Poly (I:C) increased mRNA and protein expression of PAF-R in Detroit 562 cells and enhanced the adherence of Spn to these epithelial cells. CONCLUSIONS: RNA viral infection can enhance PAF-R expression in epithelial cells and increase the adherence of Spn. These findings might explain in part the mechanisms that underlie the increase in bacterial infection following URIs.


Asunto(s)
Adhesión Bacteriana/efectos de los fármacos , Células Epiteliales/microbiología , Faringe/microbiología , Poli I-C/farmacología , Streptococcus pneumoniae/efectos de los fármacos , Adhesión Bacteriana/genética , Línea Celular Tumoral , Coinfección/microbiología , Recuento de Colonia Microbiana , Citometría de Flujo , Humanos , Técnicas In Vitro , Microscopía Fluorescente , Glicoproteínas de Membrana Plaquetaria/genética , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores Acoplados a Proteínas G/genética , Infecciones del Sistema Respiratorio/microbiología , Streptococcus pneumoniae/genética
14.
Rhinology ; 46(1): 75-8, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18444498

RESUMEN

A 12-year-old boy complained of swelling of the left cheek. Fiberscopic examination revealed the presence of a soft reddish mass in the middle meatus of the left nostril. CT scan showed a large mass completely filling the left maxillary sinus. The lesion originated from the maxillary sinus and extended to the middle nasal meatus; bone destruction and invasion of the subcutaneous tissue of the cheek were noted. T2-weighted MRI images revealed a heterogeneous signal in the left maxillary sinus. Under general anaesthesia, biopsies were obtained through an intraoral incision. On pathology, atypical cells containing irregular nuclei with scanty cytoplasm were noted. The tumour cells were strongly positive for CD99 and reacted weakly with NSE however the cells were negative for synaptophysin, LCA and cytokeratin on immunohistochemical examination. Based on these findings, the tumour was diagnosed as a Ewing's sarcoma/primitive neuroectodermal tumour. The patient was treated with radiotherapy and combination chemotherapy; subsequently, the tumour's size decreased markedly. After 20 months of follow-up, the patient showed no evidence of local tumour growth or metastasis.


Asunto(s)
Neoplasias del Seno Maxilar/diagnóstico por imagen , Tumores Neuroectodérmicos Primitivos/diagnóstico por imagen , Sarcoma de Ewing/diagnóstico por imagen , Niño , Terapia Combinada , Humanos , Masculino , Neoplasias del Seno Maxilar/patología , Neoplasias del Seno Maxilar/terapia , Tumores Neuroectodérmicos Primitivos/patología , Tumores Neuroectodérmicos Primitivos/terapia , Radiografía , Sarcoma de Ewing/patología , Sarcoma de Ewing/terapia
15.
Vaccine ; 25(14): 2680-7, 2007 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-17270319

RESUMEN

Phosphorylcholine (PC) is a structural component of a wide variety of pathogens including Streptococcus pneumoniae and Haemophilus influenzae, and anti-PC immune responses are known to protect mice against invasive bacterial diseases. The present study tested the capability of PC as an intranasal plurispecific vaccine against upper airway infections. BALB/c mice immunized with intranasal PC-keyhole limpet hemocyanin (KLH) plus cholera toxin (CT) as a mucosal adjuvant showed increased PC-specific IgM in serum, IgA in nasal wash and saliva, and numbers of PC-specific nasal and splenic antibody producing cells. Enhanced production of IL-4 and IFN-gamma by CD4+ T cells indicated the participation of Th2- and Th1-type cells. Salivary IgA antibodies produced by intranasal immunization with PC-KLH plus CT reacted to most strains of S. pneumoniae and H. influenzae. Further we demonstrated that the clearance of S. pneumoniae and H. influenzae from the nasal tract was significantly enhanced by nasal immunization with PC-KLH and CT. Thus, intranasal vaccination to induce PC-specific immune responses might help to prevent upper airway infections caused by S. pneumoniae and H. influenzae.


Asunto(s)
Anticuerpos Antibacterianos/biosíntesis , Haemophilus influenzae/inmunología , Fosforilcolina/inmunología , Streptococcus pneumoniae/inmunología , Administración Intranasal , Animales , Toxina del Cólera/inmunología , Femenino , Hemocianinas/inmunología , Inmunidad Mucosa , Inmunización , Inmunoglobulina A Secretora/biosíntesis , Ratones , Ratones Endogámicos BALB C , Fosforilcolina/administración & dosificación , Células TH1/inmunología , Células Th2/inmunología
17.
Am J Kidney Dis ; 39(5): 1032-9, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-11979347

RESUMEN

Hyperhomocysteinemia, a well-recognized cardiovascular risk factor, is frequent in hemodialysis (HD) patients. A common polymorphism in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene, C-->T substitution at nucleotide 677, is associated with homocysteine (Hcy) level elevation. We examined whether three factors involved in the methionine cycle could influence plasma Hcy concentrations in HD patients: MTHFR polymorphism; vitamin B12, an essential cofactor; and folate, the substrate. In a cross-sectional study, serum vitamin B12, folate, and plasma Hcy were measured and MTHFR genotyping was performed in 534 HD patients. Effects of MTHFR genotypes, vitamin B12, and folate on plasma Hcy levels were examined in 450 HD patients not administered vitamin B12 or folate. To examine the effect of vitamin B12 on plasma Hcy concentrations, we compared plasma Hcy concentrations in HD patients with and without vitamin B12 supplementation. To examine whether functional vitamin B12 deficiency exists even in HD patients with normal vitamin B12 concentrations, 15 HD patients (serum vitamin B12 concentrations, 250 to 2,100 pg/mL) were treated with vitamin B12 (mecobalamin, 1.5 mg/d) for 8 weeks. Serum concentrations of methylmalonic acid (MMA) and vitamin B12 were measured. Hcy levels were higher and folate levels were lower in patients with the TT and CT genotypes compared with patients with the CC genotype. Analysis of covariance to determine independent predictors of high Hcy levels identified low serum vitamin B12 and folate levels and high albumin (Alb) levels in CC-genotype patients, low folate levels and high Alb levels in CT-genotype patients, and low folate levels in TT-genotype patients. Plasma Hcy levels were lower in CC- and CT-genotype patients with vitamin B12 supplementation than in those without supplementation. Vitamin B12 supplementation for 8 weeks significantly reduced MMA concentrations in HD patients with normal serum vitamin B12 concentrations. These results indicate that MTHFR genotype influences the correlation of Hcy level with vitamin B12 and folate levels in HD patients. Functional vitamin B12 deficiency may exist, even in HD patients with normal vitamin B12 concentrations. The efficacy of vitamin B12 and folate supplementation on plasma Hcy levels may depend on MTHFR genotype.


Asunto(s)
Ácido Fólico/fisiología , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/genética , Vitamina B 12/fisiología , Estudios Transversales , Suplementos Dietéticos , Femenino , Ácido Fólico/sangre , Deficiencia de Ácido Fólico/metabolismo , Genotipo , Homocisteína/sangre , Homocisteína/deficiencia , Humanos , Hiperhomocisteinemia/etiología , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/terapia , Masculino , Metilenotetrahidrofolato Reductasa (NADPH2) , Ácido Metilmalónico/sangre , Persona de Mediana Edad , Polimorfismo Genético/genética , Diálisis Renal/métodos , Vitamina B 12/sangre , Deficiencia de Vitamina B 12/metabolismo
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