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1.
J Infect Chemother ; 28(9): 1336-1339, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35691862

RESUMEN

BACKGROUND: Disseminated infections of Mycolicibacter arupensis, a slowly growing nontuberculous mycobacteria (NTM) which causes synovitis, osteomyelitis, or pulmonary infections have rarely been reported. We report a case of disseminated M. arupensis and Mycobacterium avium co-infection in a patient with anti-interferon (IFN)-γ neutralizing autoantibody-associated immunodeficiency syndrome. CASE PRESENTATION: A 68-year-old Japanese male without human immunodeficiency virus infection was referred with complaints of persistent low-grade fever, arthralgia of the upper limbs, and weight loss of 10 kg. Cervical and mediastinal lymphadenopathies as well as a nodular opacity in the right lung were detected, and biopsy specimens of the cervical lymph node yielded M. arupensis without evidence of malignant cells. M. arupensis was also detected in sputum and peripheral blood. Computed tomography (CT) revealed deterioration of the right supraclavicular lymphadenopathy with internal necrosis and multiple low-density splenic lesions. Bone marrow and aspirates from the cervical lymph node collected at initiation of treatment yielded M. avium. The presence of anti-IFN-γ neutralizing autoantibodies was detected, leading to a diagnosis of co-infection of M. arupensis and M. avium with anti-IFN-γ neutralizing autoantibody-associated immunodeficiency syndrome. Post initiation of treatment with clarithromycin, ethambutol, and rifabutin, his fever declined, and his polyarthritis resolved. He developed disseminated varicella zoster during treatment; however, a follow-up CT scan six months after treatment revealed improvement of the lymphadenopathies, consolidation in the right lung, and splenic lesions. CONCLUSION: This is the first report of disseminated M. arupensis and M. avium co-infection in a patient with anti-IFN-γ neutralizing autoantibody-associated immunodeficiency syndrome.


Asunto(s)
Coinfección , Síndromes de Inmunodeficiencia , Linfadenopatía , Infecciones por Mycobacterium no Tuberculosas , Infección por Mycobacterium avium-intracellulare , Anciano , Autoanticuerpos/uso terapéutico , Humanos , Síndromes de Inmunodeficiencia/complicaciones , Interferón gamma , Linfadenopatía/complicaciones , Linfadenopatía/diagnóstico , Masculino , Mycobacteriaceae , Infecciones por Mycobacterium no Tuberculosas/complicaciones , Infecciones por Mycobacterium no Tuberculosas/diagnóstico , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Mycobacterium avium , Infección por Mycobacterium avium-intracellulare/complicaciones , Infección por Mycobacterium avium-intracellulare/diagnóstico , Infección por Mycobacterium avium-intracellulare/tratamiento farmacológico
2.
Sci Rep ; 11(1): 21607, 2021 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-34732819

RESUMEN

Previous studies indicated residents in geriatric long-term care facilities (LTCFs) had much higher prevalence of extended-spectrum ß-lactamase-producing Enterobacteriaceae (ESBL-E) carriage than the general population. Most ESBL-E carriers are asymptomatic. The study tested the hypothesis that residents with ESBL-E carriage may accumulate inside geriatric LTCFs through potential cross-transmission after exposure to residents with prolonged ESBL-E carriage. 260 residents from four Japanese LTCFs underwent ESBL-E testing of fecal specimens and were divided into two cohorts: Cohort 1,75 patients with ≥ 2 months residence at study onset; Cohort 2, 185 patients with < 2 months residence at study onset or new admission during the study period. Three analyses were performed: (1) ESBL-E carriage statuses in Cohort 1 and Cohort 2; (2) changes in ESBL-E carriage statuses 3-12 months after the first testing and ≥ 12 months after the second testing; and (3) lengths of positive ESBL-E carriage statuses. Compared with the residents in Cohort 1, a significantly larger proportion of residents in Cohort 2 were positive for ESBL-E carriage (28.0% in Cohort 1 vs 40.0% in Cohort 2). In the subsequent testing results, 18.3% of residents who were negative in the first testing showed positive conversion to ESBL-E carriage in the second testing, while no patients who were negative in the second testing showed positive conversion in the third testing. The maximum length of ESBL-E carriage was 17 months. The findings indicated that some residents acquired ESBL-E through potential cross-transmission inside the LTCFs after short-term residence. However, no residents showed positive conversion after long-term residence, which indicates that residents with ESBL-E carriage may not accumulate inside LTCFs. Practical infection control and prevention measures could improve the ESBL-E prevalence in geriatric LTCFs.


Asunto(s)
Infección Hospitalaria/epidemiología , Infecciones por Enterobacteriaceae/epidemiología , Enterobacteriaceae/aislamiento & purificación , Instituciones de Salud/estadística & datos numéricos , Cuidados a Largo Plazo/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Infección Hospitalaria/microbiología , Infecciones por Enterobacteriaceae/microbiología , Infecciones por Enterobacteriaceae/transmisión , Femenino , Estudios de Seguimiento , Humanos , Japón/epidemiología , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Prevalencia , Pronóstico
3.
Antibiotics (Basel) ; 11(1)2021 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-35052913

RESUMEN

A high prevalence of extended-spectrum ß-lactamase-producing Enterobacterales (ESBL-PE) may call for monitoring in geriatric long-term care facilities (g-LTCFs). We surveyed the distribution of ESBL-causative gene types and antimicrobial susceptibility in ESBL-PE strains from residents in g-LTCFs, and investigated the association between ESBL-causative gene types and antimicrobial susceptibility. First, we analyzed the types of ESBL-causative genes obtained from 141 ESBL-PE strains collected from the feces of residents in four Japanese g-LTCFs. Next, we determined the minimum inhibitory concentration values for alternative antimicrobial agents against ESBL-PE, including ß-lactams and non-ß-lactams. Escherichia coli accounted for 96% of the total ESBL-PE strains. Most strains (94%) contained blaCTX-M group genes. The genes most commonly underlying resistance were of the blaCTX-M-9 and blaCTX-M-1 groups. Little difference was found in the distribution of ESBL-causative genes among the facilities; however, antimicrobial susceptibility differed widely among the facilities. No specific difference was found between antimicrobial susceptibility and the number of ESBL-causative genes. Our data showed that ESBL-PEs were susceptible to some antimicrobial agents, but the susceptibility largely differed among facilities. These findings suggest that each g-LTCF may require specific treatment strategies based on their own antibiogram. Investigations into drug resistance should be performed in g-LTCFs as well as acute medical facilities.

4.
BMC Geriatr ; 20(1): 481, 2020 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-33208107

RESUMEN

BACKGROUND: A high prevalence of methicillin-resistant Staphylococcus aureus (MRSA) colonization has been reported among residents in geriatric long-term care facilities (LTCFs). Some studies indicate that MRSA might be imported from hospitals into LTCFs via resident transfer; however, other studies report that high MRSA prevalence might be caused by cross-transmission inside LTCFs. We aimed to assess which factors have a large impact on the high MRSA prevalence among residents of geriatric LTCFs. METHODS: We conducted a cohort study among 260 residents of four geriatric LTCFs in Japan. Dividing participants into two cohorts, we separately analyzed (1) the association between prevalence of MRSA carriage and length of LTCF residence (Cohort 1: n = 204), and (2) proportion of residents identified as MRSA negative who were initially tested at admission but subsequently identified as positive in secondary testing performed at ≥2 months after their initial test (Cohort 2: n = 79). RESULTS: Among 204 residents in Cohort 1, 20 (9.8%) were identified as positive for MRSA. Compared with residents identified as MRSA negative, a larger proportion of MRSA-positive residents had shorter periods of residence from the initial admission (median length of residence: 5.5 vs. 2.8 months), although this difference was not statistically significant (p = 0.084). Among 79 residents in Cohort 2, 60 (75.9%) were identified as MRSA negative at the initial testing. Of these 60 residents, only one (1.7%) had subsequent positive conversion in secondary MRSA testing. In contrast, among 19 residents identified as MRSA positive in the initial testing, 10 (52.6%) were negative in secondary testing. CONCLUSIONS: The prevalence of MRSA was lower among residents with longer periods of LTCF residence than among those with shorter periods. Furthermore, few residents were found to become MRSA carrier after their initial admission. These findings highlight that MRSA in LTCFs might be associated with resident transfer rather than spread via cross-transmission inside LTCFs.


Asunto(s)
Infección Hospitalaria , Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Anciano , Estudios de Cohortes , Humanos , Japón/epidemiología , Cuidados a Largo Plazo , Prevalencia , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/epidemiología
5.
PLoS One ; 15(7): e0235747, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32658903

RESUMEN

Despite development of markers for identification of cancer stem cells, the mechanism underlying the survival and division of cancer stem cells in breast cancer remains unclear. Here we report that PKCλ expression was enriched in basal-like breast cancer, among breast cancer subtypes, and was correlated with ALDH1A3 expression (p = 0.016, χ2-test). Late stage breast cancer patients expressing PKCλhigh and ALDH1A3high had poorer disease-specific survival than those expressing PKCλlow and ALDH1A3low (p = 0.018, log rank test for Kaplan-Meier survival curves: hazard ratio 2.58, 95% CI 1.24-5.37, p = 0.011, multivariate Cox regression analysis). Functional inhibition of PKCλ through siRNA-mediated knockdown or CRISPR-Cas9-mediated knockout in ALDH1high MDA-MB 157 and MDA-MB 468 basal-like breast cancer cells led to increases in the numbers of trypan blue-positive and active-caspase 3-positive cells, as well as suppression of tumor-sphere formation and cell migration. Furthermore, the amount of CASP3 and PARP mRNA and the level of cleaved caspase-3 protein were enhanced in PKCλ-deficient ALDH1high cells. An Apoptosis inhibitor (z-VAD-FMK) suppressed the enhancement of cell death as well as the levels of cleaved caspase-3 protein in PKCλ deficient ALDH1high cells. It also altered the asymmetric/symmetric distribution ratio of ALDH1A3 protein. In addition, PKCλ knockdown led to increases in cellular ROS levels in ALDH1high cells. These results suggest that PKCλ is essential for cancer cell survival and migration, tumorigenesis, the asymmetric distribution of ALDH1A3 protein among cancer cells, and the maintenance of low ROS levels in ALDH1-positive breast cancer stem cells. This makes it a key contributor to the poorer prognosis seen in late-stage breast cancer patients.


Asunto(s)
Aldehído Oxidorreductasas/metabolismo , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/mortalidad , Regulación Neoplásica de la Expresión Génica , Isoenzimas/metabolismo , Células Madre Neoplásicas/patología , Proteína Quinasa C/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Apoptosis , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Movimiento Celular , Proliferación Celular , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Células Madre Neoplásicas/metabolismo , Pronóstico , Tasa de Supervivencia , Células Tumorales Cultivadas
7.
J Infect Chemother ; 23(1): 51-55, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27865699

RESUMEN

BACKGROUND: TNF-α plays an important role in the pathogenesis of Legionella pneumophila (Lp)-induced pneumonia. Patients undergoing anti-TNF-α therapy are at an increased risk of Lp infection. Lp infects both phagocytic and non-phagocytic cells such as airway epithelial cells; however, the role of TNF-α in airway epithelial cells is unknown. METHODS: Human airway epithelial cell line NCI-H292 was infected with Lp NUL1 strain. After infection, both intracellular growth of Lp and cell death were evaluated after treating the cells with or without TNF-α. Apoptosis was examined by performing activated caspase-3/7 staining and by using a pan-caspase inhibitor. RESULTS: Lp infected and replicated in NCI-H292 cells in a time-dependent manner, and TNF-α treatment of Lp-infected NCI-H292 cells inhibited Lp replication. Inhibitory effects of TNF-α on Lp replication were suppressed after treatment with a TNF-α-neutralizing antibody. Lp infection increased extracellular lactate dehydrogenase levels and decreased the number of living cells. Increased number of Lp-infected NCI-H292 cells showed caspase-3/7 activation, indicating they underwent apoptosis. TNF-α treatment inhibited Lp replication by increasing the apoptosis of NCI-H292 cells. CONCLUSIONS: Thus, our results suggested that airway epithelial cells were involved in the pathogenesis of Lp infection and that TNF-α played a protective role by inhibiting the intracellular replication of Lp and by increasing the apoptosis of Lp-infected airway epithelial cells. However, Lp infection should be investigated further in patients undergoing anti-TNF-α therapy who develop pneumonia.


Asunto(s)
Apoptosis/fisiología , Células Epiteliales/microbiología , Legionella pneumophila/crecimiento & desarrollo , Enfermedad de los Legionarios/microbiología , Neumonía/microbiología , Factor de Necrosis Tumoral alfa/metabolismo , Caspasa 3/metabolismo , Caspasa 7/metabolismo , Células Epiteliales/metabolismo , Humanos , Enfermedad de los Legionarios/metabolismo , Neumonía/metabolismo , Mucosa Respiratoria/metabolismo , Mucosa Respiratoria/microbiología
8.
J Infect Chemother ; 22(8): 521-5, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27236515

RESUMEN

Clostridium species and Bacillus spp. are spore-forming bacteria that cause hospital infections. The spores from these bacteria are transmitted from patient to patient via healthcare workers' hands. Although alcohol-based hand rubbing is an important hand hygiene practice, it is ineffective against bacterial spores. Therefore, healthcare workers should wash their hands with soap when they are contaminated with spores. However, the extent of health care worker hand contamination remains unclear. The aim of this study is to determine the level of bacterial spore contamination on healthcare workers' hands. The hands of 71 healthcare workers were evaluated for bacterial spore contamination. Spores attached to subject's hands were quantitatively examined after 9 working hours. The relationship between bacterial spore contamination and hand hygiene behaviors was also analyzed. Bacterial spores were detected on the hands of 54 subjects (76.1%). The mean number of spores detected was 468.3 CFU/hand (maximum: 3300 CFU/hand). Thirty-seven (52.1%) and 36 (50.7%) subjects were contaminated with Bacillus subtilis and Bacillus cereus, respectively. Nineteen subjects (26.8%) were contaminated with both Bacillus species. Clostridium difficile was detected on only one subject's hands. There was a significant negative correlation between the hand contamination level and the frequency of handwashing (r = -0.44, P < 0.01) and a significant positive correlation between the hand contamination level and the elapsed time since last handwashing (r = 0.34, P < 0.01). Healthcare workers' hands may be frequently contaminated with bacterial spores due to insufficient handwashing during daily patient care.


Asunto(s)
Infección Hospitalaria/microbiología , Mano/microbiología , Esporas Bacterianas/aislamiento & purificación , Alcoholes/farmacología , Bacillus cereus/efectos de los fármacos , Bacillus cereus/aislamiento & purificación , Bacillus subtilis/efectos de los fármacos , Bacillus subtilis/aislamiento & purificación , Clostridioides difficile/efectos de los fármacos , Clostridioides difficile/aislamiento & purificación , Infección Hospitalaria/prevención & control , Desinfección de las Manos/métodos , Personal de Salud , Humanos , Jabones , Esporas Bacterianas/efectos de los fármacos
9.
J Infect Chemother ; 22(1): 14-8, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26617349

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA) is prevalent in Japan, and the Staphylococcus cassette chromosome mec (SCCmec) type II is common among hospital-acquired MRSA isolates. Information pertaining to MRSA characteristics is limited, including SCCmec types, in primary or secondary care facilities. A total of 128 MRSA isolates (90 skin and soft tissue isolates and 38 blood isolates) were collected at a secondary care facility, Kawatana Medical Center, from 2005 to 2011. Antimicrobial susceptibility testing for anti-MRSA antibiotics and molecular testing for SCCmec and virulence genes (tst, sec, etb, lukS/F-PV) were performed. Strains positive for lukS/F-PV were analyzed by multilocus sequence typing and phage open-reading frame typing. SCCmec typing in skin and soft tissue isolates revealed that 65.6% had type IV, 22.2% had type II, 8.9% had type I, and 3.3% had type III. In blood isolates, 50.0% had type IV, 47.4% had type II, and 2.6% had type III. Minimum inhibitory concentrations, MIC(50)/MIC(90), against vancomycin, teicoplanin, linezolid, and arbekacin increased slightly in SCCmec II isolates from skin and soft tissue. MICs against daptomycin were similar between sites of isolation. SCCmec type II isolates possess tst and sec genes at a greater frequently than SCCmec type IV isolates. Four lukS/F-PV-positive isolates were divided into two clonal patterns and USA300 was not included. In conclusion, SCCmec type IV was dominant in blood, skin, and soft tissue isolates in a secondary care facility in Japan. Because antimicrobial susceptibility varies with the SCCmec type, SCCmec typing of clinical isolates should be monitored in primary or secondary care facilities.


Asunto(s)
Antibacterianos/uso terapéutico , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/microbiología , Staphylococcus aureus Resistente a Meticilina/genética , Infecciones de los Tejidos Blandos/microbiología , Staphylococcus aureus/genética , Proteínas Bacterianas/sangre , Toxinas Bacterianas , Infección Hospitalaria/sangre , Daptomicina/uso terapéutico , Dibekacina/análogos & derivados , Dibekacina/uso terapéutico , Exotoxinas , Humanos , Japón , Leucocidinas , Linezolid/uso terapéutico , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus , Sistemas de Lectura Abierta , Recombinasas/sangre , Centros de Atención Secundaria , Piel/microbiología , Staphylococcus aureus/aislamiento & purificación , Teicoplanina/uso terapéutico , Vancomicina/uso terapéutico , Factores de Virulencia
10.
Nihon Rinsho ; 74(12): 1962-1966, 2016 12.
Artículo en Japonés | MEDLINE | ID: mdl-30550650

RESUMEN

Measures for emerging and re-emerging infectious diseases are the world's common chal- lenges. It is important to construct an effective infection control and medical care system to understand the occurrence and the mode of transmission of emerging and re-emerging infec- tious diseases. However, it is feared the invasion of pathogens from abroad than ever before. Therefore, it is necessary to know the foreign surveillance data as well as Japan. Currently, the United States, Europe and Australia, has been carried out surveillance at the national lev- el. These surveillance data to reference, to expect that lead to infectious diseases clinic, which was further enhanced in Japan.


Asunto(s)
Infecciones/epidemiología , Control de Infecciones , Japón/epidemiología
11.
Chem Biodivers ; 9(6): 1045-54, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22700224

RESUMEN

A new phloroglucinol derivative, 5-deprenyllupulonol C (1), along with four other phloroglucinol derivatives, 2-5, five chalcones, 6-10, four flavanones, 11-14, two flavonol glycosides, 15 and 16, and five triterpenoids, 17-21, were isolated from the female inflorescence pellet extracts of hop (Humulus lupulus L.). Upon evaluation of these compounds against the Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol 13-acetate (TPA) in Raji cells, twelve compounds, i.e., 1-4, 11-14, 17-19, and 21, showed potent inhibitory effects on EBV-EA induction, with IC50 values in the range of 215-393 mol ratio/32 pmol TPA. In addition, eleven compounds, i.e., 1-4, 6, 11, 12, 14, 17, 18, and 20, were found to inhibit TPA-induced inflammation (1 µg/ear) in mice, with ID50 values in the range of 0.13-1.06 µmol per ear. Further, lupulone C (2) and 6-prenylnaringenin (14) exhibited inhibitory effects on skin-tumor promotion in an in vivo two-stage mouse-skin carcinogenesis test based on 7,12-dimethylbenz[a]anthracene (DMBA) as initiator and with TPA as promoter.


Asunto(s)
Antiinflamatorios/química , Anticarcinógenos/química , Humulus/química , Floroglucinol/análogos & derivados , 9,10-Dimetil-1,2-benzantraceno/toxicidad , Animales , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Anticarcinógenos/farmacología , Anticarcinógenos/uso terapéutico , Antígenos Virales/química , Antígenos Virales/metabolismo , Carcinógenos/toxicidad , Edema/inducido químicamente , Edema/tratamiento farmacológico , Femenino , Espectroscopía de Resonancia Magnética , Ratones , Conformación Molecular , Floroglucinol/química , Floroglucinol/farmacología , Floroglucinol/uso terapéutico , Enfermedades de la Piel/inducido químicamente , Enfermedades de la Piel/tratamiento farmacológico , Neoplasias Cutáneas/inducido químicamente , Neoplasias Cutáneas/tratamiento farmacológico , Acetato de Tetradecanoilforbol/toxicidad
12.
Chem Biodivers ; 9(2): 318-30, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22344908

RESUMEN

Three prenylated chalcones, 4-hydroxyderricin (1), xanthoangelol (2), and xanthoangelol F (3), isolated from Angelica keiskei, were transformed by the fungus Aspergillus saitoi. These chalcones were converted to flavanones (i.e., 4, 8, and 12), and prenyl-chain-hydrated (i.e., 5, 7, 9-11, and 13) and ring-B-hydroxylated (i.e., 6) chalcones. The structures of three new metabolites, 7, 9, and 13, were established as 2″,3″-dihydro-4,3″-dihydroxyderricin, 6″,7″-dihydro-7″-hydroxyxanthoangelol, and 6″,7″-dihydro-7″-hydroxyxanthoangelol F, respectively. Upon evaluation of cytotoxic activities of compounds 1-13, the metabolite 7 exhibited potent cytotoxicity against HL60 cells, and this cell death was revealed to be mostly due to apoptosis. In addition, compounds 1-4, 7-10, 12, and 13 were examined for their inhibitory effects on the induction of Epstein-Barr virus early antigen (EBV-EA) by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells. All compounds tested showed inhibitory effects against EBV-EA activation with potencies higher than that of ß-carotene. Furthermore, the metabolite 13 exhibited inhibitory effect on skin tumor promotion in an in vivo two-stage mouse skin carcinogenesis test based on 7,12-dimethylbenz[a]anthracene (DMBA) as initiator, and with TPA as promoter.


Asunto(s)
Angelica/química , Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Transformación Celular Neoplásica/efectos de los fármacos , Chalconas/farmacología , Neoplasias Cutáneas/prevención & control , 9,10-Dimetil-1,2-benzantraceno/toxicidad , Animales , Antígenos Virales/metabolismo , Aspergillus/efectos de los fármacos , Aspergillus/crecimiento & desarrollo , Pruebas de Carcinogenicidad , Carcinógenos/toxicidad , Chalconas/química , Humanos , Ratones , Estructura Molecular , Prenilación , Neoplasias Cutáneas/inducido químicamente , Acetato de Tetradecanoilforbol/farmacología , Células Tumorales Cultivadas
13.
Zoolog Sci ; 28(3): 206-14, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21385062

RESUMEN

Bioconvection emerges in a dense suspension of swimming protists as a consequence of their negative-gravitactic upward migration and later settling as a blob of density greater than that of water. Thus, gravity is an important parameter governing bioconvective pattern formation. However, inconsistencies are found in previous studies dealing with the response of bioconvection patterns to increased gravity acceleration (hypergravity); the wave number of the patterns has been reported to decrease during the hypergravity phases of parabolic aircraft flight, while it increases in centrifugal hypergravity. In this paper, we reassess the responses of bioconvection to altered gravity during parabolic flight on the basis of vertical and horizontal observations of the patterns formed by Tetrahymena thermophila and Chlamydomonas reinhardtii. Spatiotemporal analyses of the horizontal patterns revealed an increase in the pattern wave number in both pre- and post-parabola hypergravity. Vertical pattern analysis was generally in line with the horizontal pattern analysis, and further revealed that hypergravity-induced changes preceded at the top layer of the suspensions while microgravity-induced changes appeared to occur from the bottom part of the settling blobs. The responses to altered gravity were rather different between the two sample species: T. thermophila tended to drastically modify its bioconvection patterns in response to changes in gravity level, while the patterns of C. reinhardtii responded to a much lesser extent. This difference can be attributed to the distinct physical and physiological properties of the individual organisms, suggesting a significant contribution of the gyrotactic property to the swimming behavior of some protists.


Asunto(s)
Chlamydomonas reinhardtii/fisiología , Gravitropismo , Tetrahymena/fisiología , Simulación de Ingravidez , Ingravidez , Convección
14.
J Nat Prod ; 74(2): 137-44, 2011 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-21250700

RESUMEN

Six lanostane-type triterpene acids (1a-6a), isolated from Poria cocos , and their methyl ester (1b-6b) and hydroxy derivatives (1c-6c) were prepared. Upon evaluation of the cytotoxic activity of these compounds against leukemia (HL60), lung (A549), melanoma (CRL1579), ovary (NIH:OVCAR-3), breast (SK-BR-3), prostate (DU145), stomach (AZ521), and pancreas (PANC-1) cancer cell lines, 11 compounds (5a, 6a, 2b-5b, 1c, and 3c-6c) exhibited activity with single-digit micromolar IC(50) values against one or more cell lines. Poricotriol A (1c), a hydroxy derivative of poricoic acid A (1a), exhibited potent cytotoxicities against six cell lines with IC(50) values of 1.2-5.5 µM. Poricotriol A induced typical apoptotic cell death in HL60 and A549 cells on evaluation of the apoptosis-inducing activity by flow cytometric analysis. Western blot analysis in HL60 cells showed that poricotriol A activated caspases-3, -8, and -9, while increasing the ratio of Bax/Bcl-2. This suggested that poricotriol A induced apoptosis via both mitochondrial and death receptor pathways in HL60. On the other hand, poricotriol A did not activate caspases-3, -8, and -9, but induced translocation of apoptosis-inducing factor (AIF) from mitochondria and increased the ratio of Bax/Bcl-2 in A549. This suggested that poricotriol A induced apoptosis via the mitochondrial pathway mostly by translocation of AIF, independent from the caspase pathway in A549. Furthermore, poricotriol A was shown to possess high selective toxicity in lung cancer cells since it exhibited only weak cytotoxicity against a normal lung cell line (WI-38).


Asunto(s)
Antineoplásicos/aislamiento & purificación , Antineoplásicos/farmacología , Factor Inductor de la Apoptosis/farmacología , Poria/química , Triterpenos/aislamiento & purificación , Triterpenos/farmacología , Antineoplásicos/química , Factor Inductor de la Apoptosis/química , Factor Inductor de la Apoptosis/aislamiento & purificación , Caspasas/metabolismo , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Células HL-60 , Humanos , Concentración 50 Inhibidora , Masculino , Estructura Molecular , Triterpenos/química
15.
Chem Biodivers ; 7(8): 1871-84, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20730953

RESUMEN

Nineteen known triterpenoids, 1-19, and one known sesquiterpenoid, 20, were isolated from dammar resin obtained from Shorea javanica K. & V. (Dipterocarpaceae). One of the acidic triterpenoids, dammarenolic acid (1), was converted to fourteen derivatives, namely, an alcohol, 21, an aldehyde, 22, and twelve L-amino acid conjugates, 23-34. Compounds 1-34 were examined for their inhibitory effects on the induction of Epstein-Barr virus early antigen (EBV-EA) by 12-O-tetradecanoylphorbol 13-acetate (TPA) in Raji cells, a known primary screening test for antitumor promoters. All of the compounds tested, except for compounds 4, 5, 12-14, 16, and 17, showed inhibitory effects against EBV-EA activation with potencies either comparable with or stronger than that of beta-carotene, a known natural antitumor promoter. In addition, (20S)-20-hydroxy-3,4-secodammara-4(28),24-dien-3-al (22) exhibited inhibitory effects on skin tumor promotion in an in vivo two-stage mouse skin carcinogenesis test based on 7,12-dimethylbenz[a]anthracene (DMBA) as initiator, and with TPA as promoter. Furthermore, evaluation of the cytotoxic activities of compounds 1-34 against human cancer cell lines showed that reduction (i.e., 21 and 22) or conjugation with L-amino acids (i.e., 23-34) of compound 1 enhanced the cytotoxicity against human melanoma cell line CRL1579.


Asunto(s)
Antineoplásicos/farmacología , Antineoplásicos/toxicidad , Resinas de Plantas/farmacología , Resinas de Plantas/toxicidad , Triterpenos/farmacología , Triterpenos/toxicidad , Animales , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Dipterocarpaceae/química , Humanos , Ratones , Estructura Molecular , Papiloma/tratamiento farmacológico , Resinas de Plantas/química , Neoplasias Cutáneas/tratamiento farmacológico , Triterpenos/química
16.
J Oleo Sci ; 59(4): 213-21, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20299768

RESUMEN

Ten cyclic diarylheptanoids (1-10), including three new compounds: myricanone 5-O-alpha-L-arabinofuranosyl-(1-->6)-beta-D-glucopyranoside (7), myricanone 17-O-beta-D-(6'-O-galloyl)-glucopyranoside (8), and 16-methoxy acerogenin B 9-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside (10), along with two flavonoids (11, 12), were isolated from the extracts of Myrica rubra (Myricaceae) bark. The structures of new compounds were determined on the basis of spectroscopic methods. On evaluation of compounds 1-12 against the melanogenesis in the B16 melanoma cells, six compounds, 3, 5, 7, 8, 10, and 12, exhibited inhibitory effects with 30-56% reduction of melanin content at 25 microg/mL with no or very weak toxicity to the cells (82-103% of cell viability at 25 microg/mL). In addition, upon evaluation of compounds 1-12 against the scavenging activities of free radicals [against the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical], seven compounds, 1, 3, 5, 6, 8, 11, and 12, showed potent scavenging activity [IC(50) 2-21 microM (0.6-7.3 microg/mL)].


Asunto(s)
Diarilheptanoides/aislamiento & purificación , Diarilheptanoides/farmacología , Depuradores de Radicales Libres , Melaninas/metabolismo , Melanoma Experimental/metabolismo , Myricaceae/química , Fenoles/aislamiento & purificación , Fenoles/farmacología , Extractos Vegetales/química , Animales , Compuestos de Bifenilo , Bovinos , Depresión Química , Diarilheptanoides/química , Flavonoides/aislamiento & purificación , Melanoma Experimental/patología , Ratones , Fenoles/química , Picratos , Corteza de la Planta , Células Tumorales Cultivadas
17.
J Oleo Sci ; 59(1): 49-57, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20032599

RESUMEN

A new iridoid glycoside, 9-epi-6alpha-methoxy geniposidic acid (4), three new hemiterpene glycosides, 3-methylbut-3-enyl 2'-O-(beta-D-glucopyranosyl)-beta-D-glucopyranoside (nonioside K) (6), 3-methylbut-3-enyl 6'-O-(beta-D-xylopyranosyl)-beta-D-glucopyranoside (nonioside L) (8), and 3-methylbut-3-enyl 6'-O-(beta-D-xylofuranosyl)-beta-D-glucopyranoside (nonioside M) (9), and two new saccharide fatty acid esters, 6'-O-(beta-D-glucopyranosyl)-1'-O-[(2xi)-2-methylbutanoyl]-beta-D-glucopyranose (nonioside N) (16) and 6'-O-(beta-D-xylopyranosyl)-1'-O-[(2xi)-2-methylbutanoyl]-beta-D-glucopyranose (nonioside O) (17), were isolated from a methanol extract of the fruits of Morinda citrifolia (noni), along with 11 known compounds, namely, three iridoid glycosides (1-3), two hemiterpene glycosides (5 and 7), and five saccharide fatty acid esters (10-15). Upon evaluation of compounds 1-17 on the melanogenesis in the B16 melanoma cells induced with alpha-melanocyte-stimulating hormone (alpha-MSH), 13 compounds (1, 3, 4, 6-14, and 17) exhibited marked inhibitory effects with 34-49% reduction of melanin content at 100 muM with no or almost no toxicity to the cells (91-116% of cell viability at 100 microM).


Asunto(s)
Antineoplásicos , Ácidos Grasos/química , Frutas/química , Glicósidos/química , Iridoides/química , Melaninas/antagonistas & inhibidores , Morinda/química , Terpenos/química , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Ácidos Grasos/farmacología , Glicósidos/farmacología , Humanos , Iridoides/farmacología , Estructura Molecular , Fitoterapia , Pigmentación/efectos de los fármacos , Preparaciones de Plantas , Terpenos/farmacología
18.
J Oleo Sci ; 58(11): 581-94, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19844073

RESUMEN

Thirty-one nortriterpenoids, including 28 limonoids (1-28) and 3 degraded limonoids (29-31), and one diterpenoid (32), were isolated from the seed extract of Azadirachta indica (neem). Among these, six were new compounds and their structures were established to be 15-hydroxyazadiradione (3), 7-benzoyl-17-hydroxynimbocinol (5), 23-deoxyazadironolide (12), limocin E (13), 23-epilimocin E (14), and 7alpha-acetoxy-3-oxoisocopala-1,13-dien-15-oic acid (32). Upon evaluation of compounds 1-32 on the melanogenesis in the B16 melanoma cells, five compounds, 20, 26, 27, 29, and 31, exhibited marked inhibitory effect (74-91% reduction of melanin content at 25 microg/mL) with no or almost no toxicity to the cells. Seven compounds, 1, 6, 9, 10, 18, 20, and 26, on evaluation for their inhibitory effect against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation (1 microg/ear) in mice, exhibited, except for compound 26, marked anti-inflammatory activity (ID(50) values 0.09-0.26 mg/ear). In addition, all of the 32 compounds exhibited moderate or potent inhibitory effects (IC(50) values of 230-501 mol ratio/32 pmol TPA) against the Epstein-Barr virus early antigen (EBV-EA) activation induced by TPA. Furthermore, on evaluation of azadirachtin B (21) for its anti-tumor-initiating activity on the two-stage carcinogenesis of mouse skin tumor induced by peroxynitrite (ONOO-; PN) as an initiator and TPA as a promoter, this exhibited marked inhibitory activity.


Asunto(s)
Antiinflamatorios no Esteroideos/química , Antineoplásicos Fitogénicos/química , Azadirachta/química , Limoninas/química , Melaninas/antagonistas & inhibidores , Melaninas/biosíntesis , Semillas , Animales , Antiinflamatorios no Esteroideos/aislamiento & purificación , Antiinflamatorios no Esteroideos/uso terapéutico , Antineoplásicos Fitogénicos/aislamiento & purificación , Antineoplásicos Fitogénicos/uso terapéutico , Azadirachta/fisiología , Ensayos de Selección de Medicamentos Antitumorales/métodos , Limoninas/aislamiento & purificación , Limoninas/uso terapéutico , Espectroscopía de Resonancia Magnética , Melanoma Experimental/metabolismo , Melanoma Experimental/prevención & control , Ratones , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/uso terapéutico , Células Tumorales Cultivadas
19.
J Nat Prod ; 72(10): 1786-92, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19746919

RESUMEN

Nine new (1, 3, 5, 8, 12, 13, 15, 17, and 18) and nine known (2, 4, 6, 7, 9-11, 14, and 16) lanostane-type triterpene acids and a known diterpene acid (19) were isolated from the epidermis of the sclerotia of Poria cocos. The structures of the new compounds were established as 16alpha,27-dihydroxydehyrotrametenoic acid (1), 25-hydroxy-3-epitumulosic acid (3), 16alpha,25-dihydroxyeburiconic acid (5), 25-methoxyporicoic acid A (8), 26-hydroxyporicoic acid DM (12), 25-hydroxyporicoic acid C (13), poricoic acid GM (15), poricoic acid HM (17), and 6,7-dehydroporicoic acid H (18), on the basis of spectroscopic methods. On evaluation of the nine new and two of the known compounds, 4 and 19, against the Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells, all of the compounds exhibited inhibitory effects, with IC(50) values in the range 187-348 mol ratio/32 pmol TPA. In addition, compound 8 exhibited an inhibitory effect on skin tumor promotion in an in vivo two-stage carcinogenesis test using 7,12-dimethylbenz[a]anthracene (DMBA) as an initiator and TPA as a promoter. Further, 17 compounds, 1-14, 16, 18, and 19, were evaluated for their cytotoxic activity against two human tumor cell lines, HL60 (leukemia) and CRL1579 (melanoma).


Asunto(s)
Anticarcinógenos/farmacología , Antígenos Virales/efectos de los fármacos , Lanosterol/aislamiento & purificación , Lanosterol/farmacología , Poria/química , Triterpenos/aislamiento & purificación , Triterpenos/farmacología , Anticarcinógenos/química , Anticarcinógenos/aislamiento & purificación , Ensayos de Selección de Medicamentos Antitumorales , Células HL-60 , Humanos , Lanosterol/análogos & derivados , Lanosterol/química , Estructura Molecular , Acetato de Tetradecanoilforbol/farmacología , Triterpenos/química
20.
J Exp Biol ; 212(Pt 12): 1819-24, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19482999

RESUMEN

In order to characterize the energy expenditure of Paramecium, we simultaneously measured the oxygen consumption rate, using an optic fluorescence oxygen sensor, and the swimming speed, which was evaluated by the optical slice method. The standard metabolic rate (SMR, the rate of energy consumption exclusively for physiological activities other than locomotion) was estimated to be 1.18x10(-6) J h(-1) cell(-1) by extrapolating the oxygen consumption rate into one at zero swimming speed. It was about 30% of the total energy consumed by the cell swimming at a mean speed of 1 mm s(-1), indicating that a large amount of the metabolic energy (about 70% of the total) is consumed for propulsive activity only. The mechanical power liberated to the environment by swimming Paramecium was calculated on the basis of Stokes' law. This power, termed Stokes power, was 2.2x10(-9) J h(-1) cell(-1), indicating extremely low efficiency (0.078%) in the conversion of metabolic power to propulsion. Analysis of the cost of transport (COT, the energy expenditure for translocation per units of mass and distance) revealed that the efficiency of energy expenditure in swimming increases with speed rather than having an optimum value within a wide range of forced swimming, as is generally found in fish swimming. These characteristics of energy expenditure would be unique to microorganisms, including Paramecium, living in a viscous environment where large dissipation of the kinetic energy is inevitable due to the interaction with the surrounding water.


Asunto(s)
Metabolismo Energético , Consumo de Oxígeno , Paramecium/fisiología , Animales , Cinética , Modelos Lineales , Análisis de Regresión , Natación/fisiología
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