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1.
Fungal Genet Biol ; 172: 103893, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38657898

RESUMEN

Chitin is an essential structural component of fungal cell walls composed of transmembrane proteins called chitin synthases (CHSs), which have a large range of reported effects in ascomycetes; however, are poorly understood in agaricomycetes. In this study, evolutionary and molecular genetic analyses of chs genes were conducted using genomic information from nine ascomycete and six basidiomycete species. The results support the existence of seven previously classified chs clades and the discovery of three novel basidiomycete-specific clades (BI-BIII). The agaricomycete fungus Pleurotus ostreatus was observed to have nine putative chs genes, four of which were basidiomycete-specific. Three of these basidiomycete specific genes were disrupted in the P. ostreatus 20b strain (ku80 disruptant) through homologous recombination and transformants were obtained (Δchsb2, Δchsb3, and Δchsb4). Despite numerous transformations Δchsb1 was unobtainable, suggesting disruption of this gene causes a crucial negative effect in P. ostreatus. Disruption of these chsb2-4 genes caused sparser mycelia with rougher surfaces and shorter aerial hyphae. They also caused increased sensitivity to cell wall and membrane stress, thinner cell walls, and overexpression of other chitin and glucan synthases. These genes have distinct roles in the structural formation of aerial hyphae and cell walls, which are important for understanding basidiomycete evolution in filamentous fungi.


Asunto(s)
Quitina Sintasa , Quitina , Proteínas Fúngicas , Filogenia , Pleurotus , Quitina Sintasa/genética , Pleurotus/genética , Pleurotus/enzimología , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Quitina/metabolismo , Pared Celular/genética , Pared Celular/metabolismo , Evolución Molecular , Basidiomycota/genética , Basidiomycota/enzimología
2.
Lett Appl Microbiol ; 76(4)2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-37061783

RESUMEN

Hydrophobins are small-secreted proteins comprising both hydrophobic and hydrophilic parts, that can self-assemble into an amphiphilic film at the air-liquid interface. More than 20 hydrophobin genes have been estimated in the white-rot fungus Pleurotus ostreatus. In our previous studies, three hydrophobin genes were shown to be predominantly expressed under ligninolytic conditions, and only vmh3 was downregulated in both the delignification-deficient mutant Δgat1 and Δhir1 strains. Here, we focused on the function of the hydrophobin Vmh3 to clarify its physiological role in lignin degradation. When the hyphae were observed by transmission electron microscopy, deletion of vmh3 resulted in the disappearance of black aggregates at the interface between the cell wall and outer environment. Deletion of vmh3 resulted in reduced hydrophobicity when 0.2% sodium dodecyl sulfate was dropped onto the mycelial surface. These results suggest that Vmh3 functions on the cell surface and plays a major role in mycelial hydrophobization. Furthermore, the Δvmh3 strain showed a marked delay in lignin degradation on beech wood sawdust medium, while the production of lignin-modifying enzymes was not reduced. This study demonstrated, for the first time, the possible effect of hydrophobin on lignin degradation by a white-rot fungus.


Asunto(s)
Pleurotus , Pleurotus/genética , Pleurotus/metabolismo , Lignina/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
3.
Microbiology (Reading) ; 167(3)2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33555250

RESUMEN

l-Arabinose, a major constituent pentose of plant cell-wall polysaccharides, has been suggested to be a less preferred carbon source for fungi but to be a potential signalling molecule that can cause distinct genome-wide transcriptional changes in fungal cells. Here, we explore the possibility that this unique pentose influences the morphological characteristics of the phytopathogenic fungus Bipolaris maydis strain HITO7711. When grown on plate media under different sugar conditions, the mycelial dry weight of cultures on l-arabinose was as low as that with no sugar, suggesting that l-arabinose does not substantially contribute to vegetative growth. However, the intensity of conidiation on l-arabinose was comparable to or even higher than that on d-glucose and on d-xylose, in contrast to the poor conidiation under the no-sugar condition. To explore the physiological basis of the passive growth and active conidiation on l-arabinose, we next investigated cellular responses of the fungus to these sugar conditions. Transcriptional analysis of genes related to carbohydrate metabolism showed that l-arabinose stimulates carbohydrate utilization through the hexose monophosphate shunt (HMP shunt), a catabolic pathway parallel to glycolysis and which participates in the generation of the reducing agent NADPH (the reduced form of nicotinamide adenine dinucleotide phosphate). Then, the HMP shunt was impaired by disrupting the related gene BmZwf1, which encodes glucose-6-phosphate dehydrogenase in this fungus. The resulting mutants on l-arabinose showed remarkably decreased conidiation, but a conversely increased mycelial dry weight compared with the wild-type. Our study demonstrates that l-arabinose acts to enhance resource allocation to asexual reproduction in B. maydis HITO7711 at the cost of vegetative growth, and suggests that this is mediated by the concomitant stimulation of the HMP shunt.


Asunto(s)
Arabinosa/metabolismo , Bipolaris/crecimiento & desarrollo , Bipolaris/metabolismo , Bipolaris/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Genes del Tipo Sexual de los Hongos , Glucosafosfato Deshidrogenasa/genética , Glucosafosfato Deshidrogenasa/metabolismo , Mutación , Micelio/genética , Micelio/crecimiento & desarrollo , Micelio/metabolismo , Reproducción Asexuada , Esporas Fúngicas/genética , Esporas Fúngicas/crecimiento & desarrollo , Esporas Fúngicas/metabolismo
4.
Molecules ; 26(18)2021 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-34577118

RESUMEN

Cancer cells employ programmed cell death ligand-1 (PD-L1), an immune checkpoint protein that binds to programmed cell death-1 (PD-1) and is highly expressed in various cancers, including cervical carcinoma, to abolish T-cell-mediated immunosurveillance. Despite a key role of PD-L1 in various cancer cell types, the regulatory mechanism for PD-L1 expression is largely unknown. Understanding this mechanism could provide a novel strategy for cervical cancer therapy. Here, we investigated the influence of ezrin/radixin/moesin (ERM) family scaffold proteins, crosslinking the actin cytoskeleton and certain plasma membrane proteins, on the expression of PD-L1 in HeLa cells. Our results showed that all proteins were expressed at mRNA and protein levels and that all ERM proteins were highly colocalized with PD-L1 in the plasma membrane. Interestingly, immunoprecipitation assay results demonstrated that PD-L1 interacted with ERM as well as actin cytoskeleton proteins. Furthermore, gene silencing of ezrin, but not radixin and moesin, remarkably decreased the protein expression of PD-L1 without affecting its mRNA expression. In conclusion, ezrin may function as a scaffold protein for PD-L1; regulate PD-L1 protein expression, possibly via post-translational modification in HeLa cells; and serve as a potential therapeutic target for cervical cancer, improving the current immune checkpoint blockade therapy.


Asunto(s)
Proteínas del Citoesqueleto , Neoplasias del Cuello Uterino , Citoesqueleto de Actina , Apoptosis , Membrana Celular/metabolismo , Femenino , Silenciador del Gen , Células HeLa , Humanos , Ligandos
5.
J Am Chem Soc ; 142(4): 1692-1697, 2020 01 29.
Artículo en Inglés | MEDLINE | ID: mdl-31939289

RESUMEN

In this paper, we report efficient cyanation of various peptides containing the α-bromocarbonyl moiety using a Cu-catalyzed radical-based methodology employing zinc cyanide as the cyanide source. Mechanistic studies revealed that in situ formed CuCN was a key intermediate during the catalytic cycle. Our method could be useful for the synthesis of modified peptides containing quaternary carbons.

6.
Biol Pharm Bull ; 43(4): 669-674, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32037352

RESUMEN

Despite in vivo studies suggesting that obesity increases carboplatin (CBDCA) bone marrow toxicity, the American Society of Clinical Oncology recommends that full weight-based cytotoxic chemotherapy doses be used to treat obese patients with cancer. Accordingly, the present study retrospectively investigated the effect of body mass index (BMI) on bone marrow toxicity in patients with gynecological cancer who underwent paclitaxel and carboplatin (TC) therapy after eliminating the effect of the target area under the curve (AUC). Risk factors for CBDCA bone marrow toxicity were also identified. A total of 110 patients with primary gynecological cancer or gynecological cancer of unknown primary origin who underwent TC therapy with a target AUC of 5-6 were included herein. Patients with a BMI of ≥25 and <25 kg/m2 were assigned to the obesity and control groups, respectively, and evaluated according to changes in hematological test values (platelet, white blood cell, and hemoglobin counts) starting from initial TC therapy administration until 21 d after the second treatment course. The obesity group had a significantly higher thrombocytopenia rate than the control group. Risk factors for thrombocytopenia ≥ grade 2 included BMI ≥25 kg/m2. Among patients with primary gynecological cancer or gynecological cancer of unknown primary origin who had a BMI of ≥25 kg/m2, those receiving CBDCA may be at increased risk for thrombocytopenia ≥ grade 2 when the dosage is calculated using the Calvert formula with the creatinine clearance level.


Asunto(s)
Antineoplásicos/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carboplatino/efectos adversos , Neoplasias de los Genitales Femeninos/tratamiento farmacológico , Obesidad/complicaciones , Paclitaxel/efectos adversos , Trombocitopenia/inducido químicamente , Anciano , Índice de Masa Corporal , Femenino , Hemoglobinas/análisis , Humanos , Recuento de Leucocitos , Persona de Mediana Edad , Obesidad/inmunología , Recuento de Plaquetas , Factores de Riesgo , Trombocitopenia/inmunología
7.
Curr Genet ; 65(5): 1229-1242, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31028454

RESUMEN

PAK (p21-activated protein kinases)-like kinases are master regulators of development and morphogenesis, which were conserved among eukaryotes, including fungi. In budding yeast, two types of PAK-like kinases, Ste20 and Cla4 have distinct but shared roles in the regulation of pseudohyphal development, budding and mating. In this study, to examine the broad functions of PAK-like kinases in growth, pathogenicity and asexual/sexual reproduction in filamentous fungi, we identified and characterized two PAK-like kinases, Ste20 and Cla4 in Bipolaris maydis. A single mutant of both Ste20 and Cla4 gene was viable, while the double mutant was not available, possibly because of lethality. In growth, conidiation, and pathogenicity, Δste20 strains showed phenotypes similar to those of the wild-type, while Δcla4 strains showed severely defected phenotypes. In this study, we also clarified that Ste20 is partially involved in pseudothecium development but is dispensable for maternity, while Cla4 is essential for maternal pseudothecium development and also involve in ascospore development in paternal pseudothecium. Fluorescent microscopy visualized the disorder in cell polarity at the hyphal tip in Δcla4. These results suggested that not Ste20 but Cla4 is a master regulator of growth, pathogenicity and asexual/sexual development in B. maydis. In addition, we successfully visualized alternation of branching pattern and distribution of Spitzenkörper at the hyphal tip in Δcla4 strains.


Asunto(s)
Ascomicetos/fisiología , Micosis/microbiología , Proteínas Serina-Treonina Quinasas/metabolismo , Ascomicetos/clasificación , División Celular/genética , Polaridad Celular/genética , Cruzamientos Genéticos , Genes Fúngicos , Hifa , Mutación , Fenotipo , Filogenia , Proteínas Serina-Treonina Quinasas/genética
8.
Int J Clin Oncol ; 24(7): 836-841, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30778794

RESUMEN

BACKGROUND: The reintroduction of oxaliplatin as a third-or-later-line regimen has been a promising option for patients with metastatic colorectal cancer (mCRC) who previously received chemotherapy including oxaliplatin. In this single-arm phase II study, we evaluated the efficacy of biweekly SOX, which is the combination of oxaliplatin reintroduction and S-1, as a third-or-later-line treatment. METHODS: Patients with mCRC who had previously received prior chemotherapy including oxaliplatin and irinotecan and were planned to receive the reintroduction of oxaliplatin were enrolled. Oxaliplatin (85 mg/m2) with/without bevacizumab (5 mg/kg) was given intravenously on day 1. Oral S-1 was administered on day 2-8 at a dose of 40-60 mg (calculated according to the body surface area) twice a day. Cycles were repeated every 2 weeks. The primary endpoint was the progression-free survival (PFS); our hypothesis was that the median PFS would be 3.5 months with a minimum threshold above 2.0 months. The secondary endpoints included the adverse events (AEs), response rate and overall survival (OS). RESULTS: A total of 41 patients from 12 institutes were enrolled. The median PFS and OS survival were 3.3 months (95% confidence interval [CI] 2.7-4.2) and 10.1 months (8.3-14.6), and response rate and disease control rate were 10.0% and 65.0%, respectively. Grade 3 AEs included thrombocytopenia (5.0%), anorexia (5.0%), pneumonia (5.0%) and fatigue (5.0%). There were no cases of grade 4 AEs or treatment-related death. CONCLUSION: Biweekly SOX regimen with reintroduction of oxaliplatin could be exploitable as the third- and/or later-line treatments for patients with mCRC.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/secundario , Oxaliplatino/administración & dosificación , Ácido Oxónico/administración & dosificación , Tegafur/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Bevacizumab/administración & dosificación , Bevacizumab/efectos adversos , Neoplasias Colorrectales/mortalidad , Neoplasias Colorrectales/patología , Supervivencia sin Enfermedad , Esquema de Medicación , Combinación de Medicamentos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oxaliplatino/efectos adversos , Ácido Oxónico/efectos adversos , Retratamiento , Tasa de Supervivencia , Tegafur/efectos adversos
9.
World J Surg Oncol ; 17(1): 33, 2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30770753

RESUMEN

BACKGROUND: Although hepatectomy for metastatic colorectal cancer (mCRC) prolongs survival in up to 40% of people, recurrence rates approach 70%. We used a multidisciplinary approach to treat recurrent liver metastases, including chemotherapy, surgery, and palliative care. On the other hand, development of chemotherapeutic agents is remarkable and improves long-term survival. However, whether chemotherapy and repeat hepatectomy combination therapy improve survival or not is still unclear. The aim of this study was to analyze the outcomes of repeat hepatectomy with systemic chemotherapy for mCRC. METHODS: Following Institutional Review Board approval, we reviewed the records of all patients who underwent hepatectomy for mCRC between 1974 and 2015 at Fujita Health University Hospital. We used the Kaplan-Meier method to estimate overall survival from the first and last hepatectomy in multi hepatectomy cases after 2005 and compared outcomes between groups using the log-rank test. RESULTS: A total of 426 liver resections were performed for mCRC; of these, 236 cases were performed after 2005 (late group). In 118 (50%) cases, the site of recurrence was the liver, 59 (50%) underwent repeat hepatectomy, and 14 cases had ≥ 2 repeat hepatectomies. Overall survival (OS) before and after 2005 was 42.2 and 64.1 months, respectively, with the late group having better OS compared to the early (1974-2004) group. OS for single hepatectomy cases was 83.2 months, for two hepatectomies was 42.9 months, and for three hepatectomies was 35.3 months. In total, 59 patients did not undergo surgery after recurrence with an OS of 28.7 months. Mortality of the second and third repeat hepatectomy was 1.7% and 15.3%, respectively. CONCLUSION: Repeat hepatectomy with systemic chemotherapy for mCRC is feasible and might achieve improved survival in carefully selected patients.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/patología , Hepatectomía , Neoplasias Hepáticas/terapia , Recurrencia Local de Neoplasia/terapia , Reoperación , Adulto , Anciano , Anciano de 80 o más Años , Supervivencia sin Enfermedad , Estudios de Factibilidad , Femenino , Fluorouracilo/uso terapéutico , Humanos , Estimación de Kaplan-Meier , Leucovorina/uso terapéutico , Hígado/patología , Hígado/cirugía , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/secundario , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/secundario , Compuestos Organoplatinos/uso terapéutico , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
10.
Curr Microbiol ; 75(7): 811-817, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29468302

RESUMEN

Myxococcus xanthus generates diadenosine tetraphosphates (Ap4A) and diadenosine pentaphosphates (Ap5A) under various stress conditions. M. xanthus lysyl-tRNA synthetase (LysS) efficiently synthesizes Ap4A from ATP, Ap5A from ATP and adenosine tetraphosphate (Ap4), and Ap4 from ATP and triphosphate. To identify other M. xanthus enzymes that can catalyze Ap4A and Ap4 synthesis, 15 M. xanthus aminoacyl-tRNA synthetases (aaRSs), four acyl-CoA synthetases (Acys), three acetyl-CoA synthetases (Aces), phosphoglycerate kinase (Pgk), and adenylate kinase (Adk) were expressed in Escherichia coli and examined for Ap4A or Ap4 synthetase activity using ATP or ATP and triphosphate as substrates. Among the tested enzymes, LysS had the highest Ap4A synthetase activity. AlaRS, SerRS, and LeuRS1 showed high ADP synthetase activity with ATP as a substrate in the presence of pyrophosphatase, and also demonstrated the ability to produce Ap4 from ATP and triphosphate in the absence of pyrophosphatase. Ap4 formation by AlaRS, SerRS, and LeuRS1 was approximately 4- to 13-fold higher compared with that of Ap4A, suggesting that these enzymes prefer triphosphate over ATP as a substrate in the second reaction. Some of the recombinant M. xanthus Acys and Aces also synthesized Ap4 from ATP and triphosphate. However, Pgk was capable of catalyzing the production of Ap4 from ATP and 3-phosphoglycerate in the presence of Mg2+ and did not require triphosphate, suggesting that this enzyme is mainly responsible for Ap4 synthesis in M. xanthus.


Asunto(s)
Proteínas Bacterianas/metabolismo , Fosfatos de Dinucleósidos/biosíntesis , Myxococcus xanthus/enzimología , Adenosina/metabolismo , Aminoacil-ARNt Sintetasas/genética , Aminoacil-ARNt Sintetasas/metabolismo , Proteínas Bacterianas/genética , Biocatálisis , Vías Biosintéticas , Coenzima A Ligasas/genética , Coenzima A Ligasas/metabolismo , Fosfatos de Dinucleósidos/genética , Fosfatos de Dinucleósidos/metabolismo , Lisina-ARNt Ligasa/genética , Lisina-ARNt Ligasa/metabolismo , Myxococcus xanthus/genética , Myxococcus xanthus/metabolismo
11.
World J Surg Oncol ; 16(1): 29, 2018 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-29439724

RESUMEN

BACKGROUND: Esophageal schwannomas are rare esophageal submucosal tumors. We herein report a case of a lobulated esophageal schwannoma resected with concurrent approach from the thorax and cervix. CASE PRESENTATION: A 74-year-old woman visited our hospital with complaint of loss of consciousness, and a lobulated mediastinal tumor was discovered by chance in computed tomography. Upper gastrointestinal endoscopy showed a smooth elevated lesion at a position of 23-28 cm from the incisor teeth. A hypermetabolic appearance was noted on positron emission tomography. Based on these data, a gastrointestinal stromal tumor was suspected. The tumor was enucleated at the thoracic cavity while being pushed from the cervical incision. Pathological examination showed an esophageal schwannoma. CONCLUSIONS: We experienced a case of lobulated esophageal schwannoma with fluorodeoxyglucose accumulation. We resected the tumor with concurrent approach from the thorax and cervix.


Asunto(s)
Cuello del Útero/cirugía , Neoplasias Esofágicas/cirugía , Tumores del Estroma Gastrointestinal/cirugía , Neoplasias del Mediastino/cirugía , Neurilemoma/cirugía , Tórax/patología , Anciano , Cuello del Útero/diagnóstico por imagen , Cuello del Útero/patología , Neoplasias Esofágicas/diagnóstico por imagen , Neoplasias Esofágicas/patología , Femenino , Tumores del Estroma Gastrointestinal/diagnóstico por imagen , Tumores del Estroma Gastrointestinal/patología , Humanos , Neoplasias del Mediastino/diagnóstico por imagen , Neoplasias del Mediastino/patología , Neurilemoma/diagnóstico por imagen , Neurilemoma/patología , Tomografía de Emisión de Positrones , Pronóstico , Tórax/diagnóstico por imagen
12.
Mycorrhiza ; 28(1): 17-28, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29046936

RESUMEN

Non-ectomycorrhizal fungi that associate with typical ectomycorrhizae often remain hidden, and their localization inside ectomycorrhizal (ECM) roots has remained uncharacterized. In this study, the fungal community associated with the ectomycorrhizae of Castanopsis cuspidata was investigated using a culture-dependent isolation technique. Additionally, the species composition and localization were determined using molecular techniques. The results of the isolation and identification of fungal species revealed the predominance of a few species belonging to the order Helotiales. Furthermore, the fungal community structures were significantly different depending on the taxa of the ectomycorrhiza-forming fungi. A taxon-specific probe was developed to analyze the localization of one dominant Hyaloscyphaceae (Helotiales) species in ECM tissues by in situ hybridization. Hybridization signals were detected on the surface of the fungal mantle and around the ECM fungal cells within the mantle. Hyphal penetration into ECM hyphal cells of fungal mantles was also observed. Signals were not detected in the Hartig net or plant tissues inside the mantle in healthy ectomycorrhizae. These findings suggest that the analyzed species interact not only with host plant as root endophyte but also directly with the ECM fungi.


Asunto(s)
Ascomicetos/fisiología , Fagaceae/microbiología , Micorrizas/fisiología , Ascomicetos/clasificación , Hibridación in Situ , Micorrizas/clasificación , Raíces de Plantas/microbiología , Árboles/microbiología
13.
Microbiology (Reading) ; 163(1): 86-93, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27902428

RESUMEN

Diadenosine polyphosphates (ApnA) are thought to act as signalling molecules regulating stress responses and biofilm formation in prokaryotes. However, ApnA function in Myxococcus xanthus remains unknown. Here, we investigated the role of ApnA in M. xanthus, using the wild-type and ApnA hydrolase (apaH) mutant strains exposed to various stress conditions. In both wild-type and apaH mutant cells cultured on starvation medium (CF agar), the levels of intracellular diadenosine tetraphosphate (Ap4A) and pentaphosphate (Ap5A) increased several fold during the first 16 h of development and decreased gradually thereafter. The levels of Ap4A and Ap5A in the apaH mutant were about 5- and 11-fold higher than those in the wild-type strain at 16 h, respectively. ApnA hydrolase activity of the wild-type strain increased 1.5-fold during the first 8 h of development, and it then gradually decreased. The apaH mutant formed spores 1-2 days after the wild-type strain did, and the yield of viable spores was 5.5 % of that in the wild-type strain 5 days after inoculation onto CF agar. These results suggest the possibility that high intracellular levels of Ap4A and/or Ap5A may inhibit M. xanthus sporulation at the early stage of development and that the bacteria reduce intracellular Ap4A and Ap5A accumulation through ApnA hydrolase activity.


Asunto(s)
Ácido Anhídrido Hidrolasas/genética , Fosfatos de Dinucleósidos/metabolismo , Myxococcus xanthus/metabolismo , Esporas Bacterianas/crecimiento & desarrollo , Adenosina Trifosfato/metabolismo , Transducción de Señal , Inanición
14.
Ann Surg Oncol ; 24(2): 546-553, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27638675

RESUMEN

BACKGROUND: Advantages of neoadjuvant chemotherapy combined with monoclonal antibodies for treating patients with resectable colorectal cancer liver metastasis (CLM) have not been established. The purpose of this study was to evaluate the efficacy and safety of oxaliplatin-based regimen (FOLFOX or XELOX) plus monoclonal antibodies (cetuximab or bevacizumab) treatment in patients with resectable CLM. METHODS: A single-arm, open-label, multicenter, phase II trial was conducted for patients aged ≥ 20 years with resectable and untreated CLM. Patients received preoperative FOLFOX (6 cycles) or XELOX (4 cycles). Cetuximab or bevacizumab was administered to patients with wild-type or mutated KRAS codons 12 and 13, respectively. The primary endpoint was progression-free survival (PFS). RESULTS: Between January 2010 and June 2012, 47 patients were enrolled from 12 institutions. Wild-type or mutant KRAS sequences were examined in 32 and 15 patients, respectively. Twenty-one (45 %) patients experienced Grades 3/4 adverse events, and 55 % of all patients responded to therapy. The sizes of tumors of patients in the wild-type KRAS group were significantly reduced compared with those of the mutant KRAS group. The overall rates of liver resection and postoperative morbidity were 83 and 14 %, respectively, and the median PFS was 15.6 months. The median PFS times of the KRAS wild-type and mutant groups were 22.5 months and 10.5 months, respectively. CONCLUSIONS: Neoadjuvant therapy using FOLFOX/XELOX combined with monoclonal antibodies did not improve PFS, although it was administered safely and had less adverse effects after liver resection.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Terapia Molecular Dirigida , Terapia Neoadyuvante , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/administración & dosificación , Bevacizumab/administración & dosificación , Capecitabina/administración & dosificación , Cetuximab/administración & dosificación , Neoplasias Colorrectales/patología , Femenino , Estudios de Seguimiento , Humanos , Leucovorina/administración & dosificación , Neoplasias Hepáticas/secundario , Masculino , Persona de Mediana Edad , Compuestos Organoplatinos/administración & dosificación , Oxaliplatino , Pronóstico , Estudios Prospectivos , Tasa de Supervivencia
15.
Biosci Biotechnol Biochem ; 81(1): 102-111, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27691719

RESUMEN

Tricholoma matsutake, a basidiomycete, forms ectomycorrhizas with Pinus densiflora as the host tree. Its fruiting body, "matsutake" in Japanese, is an edible and highly prized mushroom, and it grows in a circle called a fairy ring. Beneath the fairy ring of T. matsutake, a whitish mycelium-soil aggregated zone, called "shiro" in Japanese, develops. The front of the shiro, an active mycorrhizal zone, functions to gather nutrients from the soil and roots to nourish the fairy ring. Bacteria and sporulating fungi decrease from the shiro front, whereas they increase inside and outside the shiro front. Ohara demonstrated that the shiro front exhibited antimicrobial activity, but the antimicrobial substance has remained unidentified for 50 years. We have identified the antimicrobial substance as the (oxalato)aluminate complex, known as a reaction product of oxalic acid and aluminum phosphate to release soluble phosphorus. The complex protects the shiro from micro-organisms, and contributes to its development.


Asunto(s)
Aluminio/química , Compuestos Organometálicos/química , Compuestos Organometálicos/farmacología , Oxalatos/química , Microbiología del Suelo , Tricholoma/efectos de los fármacos , Antiinfecciosos/química , Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , Hongos/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Compuestos Organometálicos/aislamiento & purificación
16.
Int J Clin Oncol ; 21(3): 566-72, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26475356

RESUMEN

BACKGROUND: The aim of this multicenter, open-label, randomized phase II trial was to evaluate the efficacy of a dose-dense capecitabine and oxaliplatin (XELOX) regimen in patients with metastatic colorectal cancer (mCRC) for whom reintroduction of oxaliplatin had been planned as a third- or later-line regimen. METHODS: The patients with mCRC who had received prior chemotherapy including oxaliplatin and were scheduled for reintroduction of oxaliplatin were randomized to capecitabine (1,000 mg/m(2)) twice daily on days 1-14 and oxaliplatin (130 mg/m(2)) on day 1 every 21 days (Q3W group) or capecitabine (2,000 mg/m(2)) twice daily on days 1-7 and oxaliplatin (85 mg/m(2)) on day 1 every 14 days (Q2W group). The primary endpoint was the time-to-treatment failure (TTF). Other endpoints included overall survival (OS), progression-free survival (PFS) and other adverse events (AEs). RESULTS: A total of 46 patients were enrolled in the trial-22 patients were randomly assigned to the Q3W group and 23 to the Q2W group. The median TTF was 3.4 months in both groups (hazard ratio [HR] 1.053; p = 0.880). The median PFS and OS were 3.3 and 9.2 months in the Q2W group and 4.3 and 12.1 months in the Q3W group, respectively (HR 1.15; p = 0.153 and 0.672; p = 0.836). The most common grade 3-4 AEs in the Q3W and Q2W groups were fatigue (27.3 vs 21.7), neuropathy (9.1 vs 0 %) and diarrhea (9.1 vs 0 %), respectively. CONCLUSION: There was no significant inter-group difference in any of the efficacy and safety endpoints, including TTF, OS, RFS and AEs. The results of this clinical trial were convincingly negative.


Asunto(s)
Antineoplásicos/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Desoxicitidina/análogos & derivados , Fluorouracilo/análogos & derivados , Compuestos Organoplatinos/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Capecitabina , Desoxicitidina/administración & dosificación , Desoxicitidina/efectos adversos , Diarrea/inducido químicamente , Supervivencia sin Enfermedad , Esquema de Medicación , Fatiga/inducido químicamente , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Enfermedades del Sistema Nervioso/inducido químicamente , Compuestos Organoplatinos/efectos adversos , Oxaliplatino , Oxaloacetatos , Retratamiento , Tasa de Supervivencia
17.
World J Surg Oncol ; 14(1): 47, 2016 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-26912337

RESUMEN

BACKGROUND: Carcinoma and adenoma of the duodenum, including the papilla of Vater, are problematic diseases in patients with familial adenomatous polyposis (FAP). CASE PRESENTATION: A 36-year-old man underwent a periodic medical examination for early colon cancer originating from FAP for which laparoscopic-assisted subtotal colectomy with a J-shaped ileal pouch-rectal anastomosis was performed 3 years earlier. A tumor was detected at the papilla of Vater along with elevation of total bilirubin and hepatobiliary enzymes. Although cytology did not determine the tumor to be an adenocarcinoma, we suspected adenocarcinoma due to its hypervascularity shown by contrast-enhanced computed tomography. Pylorus-preserving pancreaticoduodenectomy with modified Imanaga reconstruction and regional lymph node dissection (D2) was performed. The pathological study showed that the tumor was a papillary and moderately differentiated tubular adenocarcinoma. The patient is currently in good health without recurrence, weight loss, or severe diarrhea at 12 months after surgery. CONCLUSIONS: Awareness of biliary-pancreatic symptoms and periodic gastroduodenoscopy might contribute both to the early detection of duodenal or periampullary polyps and cancer and to the radical treatment of FAP. Modified Imanaga reconstruction has the potential to become one of the more effective procedures for providing good quality of life to FAP patients with duodenal or periampullary cancer.


Asunto(s)
Poliposis Adenomatosa del Colon/cirugía , Ampolla Hepatopancreática/patología , Colectomía/efectos adversos , Neoplasias del Conducto Colédoco/etiología , Complicaciones Posoperatorias , Adulto , Ampolla Hepatopancreática/cirugía , Neoplasias del Conducto Colédoco/patología , Neoplasias del Conducto Colédoco/cirugía , Humanos , Masculino , Pronóstico
18.
J Surg Case Rep ; 2024(5): rjae276, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38706478

RESUMEN

In selected patients with metastatic renal cell carcinoma, metastasectomy can achieve prolonged survival. Herein we report a patient with concomitant pancreatic and duodenal metastases occurring 12 years after total right nephrectomy for a renal cell carcinoma. The metastases were successfully treated by a pancreas-sparing duodenectomy and distal pancreatectomy. A 66-year-old man was referred to our hospital with a chief complaint of right upper abdominal pain. He had undergone laparoscopic total right nephrectomy for renal cell carcinoma 12 years before. Enhanced computed tomography showed hypervascular tumors in the pancreatic body and the descending duodenum near the papilla of Vater. Histopathological examination of endoscopic ultrasonography-guided fine needle aspiration cytology specimens revealed metastatic clear cell renal cancer. The patient underwent pancreas-sparing duodenectomy and distal pancreatectomy. He developed a pancreatic fistula after surgery that improved with conservative treatment, and has been free of evidence of recurrence up to 20 months postoperatively.

19.
J Surg Case Rep ; 2024(5): rjae311, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38764731

RESUMEN

A paraduodenal hernia is a rare cause of an internal hernia that may require massive bowel resection; prompt diagnosis and surgical treatment are essential. In cases of malrotation, strangulation may occur both inside and outside the hernial sac. Strangulation outside the hernial sac makes the preoperative diagnosis more difficult. Herein, we report a patient with a right paraduodenal hernia, intestinal malrotation, and strangulation outside the hernia. An 86-year-old woman was admitted to our hospital with abdominal pain. Enhanced computed tomography showed a closed-loop obstruction of the hypo-enhancing small bowel and absence of a horizontal duodenal leg. The patient underwent an emergency laparotomy and was diagnosed with strangulated bowel obstruction due to a right paraduodenal hernia and malrotation. The patient underwent resection of the ischemic ileum, closure of the hernial orifice, and repositioning of the intestine. The postoperative course was uneventful. The patient reported no abdominal discomfort after 7 months of follow-up.

20.
Org Lett ; 25(16): 2840-2845, 2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37057823

RESUMEN

We report the sequence-regulated radical additions of tert-alkyl radicals to two different olefins controlled by a Cu catalyst, which we term the "atom-transfer radical addition-substitution" reaction. The reactions of α-bromocarbonyl compounds, such as tert-alkyl radical sources, with methacrylates and styrenes occur in a sequence-regulated manner to give the corresponding three-component product possessing skipped quaternary carbon centers. Our method provides new insight into how to control the reactivities of tert-alkyl radicals during the synthesis of regulated aliphatic chains.

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