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1.
Nano Lett ; 22(23): 9748-9756, 2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36318636

RESUMEN

Optically active defects in 2D materials, such as hexagonal boron nitride (hBN) and transition-metal dichalcogenides (TMDs), are an attractive class of single-photon emitters with high brightness, operation up to room temperature, site-specific engineering of emitter arrays with strain and irradiation techniques, and tunability with external electric fields. In this work, we demonstrate a novel approach to precisely align and embed hBN and TMDs within background-free silicon nitride microring resonators. Through the Purcell effect, high-purity hBN emitters exhibit a cavity-enhanced spectral coupling efficiency of up to 46% at room temperature, exceeding the theoretical limit (up to 40%) for cavity-free waveguide-emitter coupling and demonstrating nearly a 1 order of magnitude improvement over previous work. The devices are fabricated with a CMOS-compatible process and exhibit no degradation of the 2D material optical properties, robustness to thermal annealing, and 100 nm positioning accuracy of quantum emitters within single-mode waveguides, opening a path for scalable quantum photonic chips with on-demand single-photon sources.

2.
J Clin Oncol ; 16(5): 1869-78, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9586903

RESUMEN

PURPOSE: To evaluate the efficacy and toxicity of combination chemotherapy with bleomycin, vincristine, mitomycin, and consecutive low-dose (CLD) administration of cisplatin (CLD-BOMP) for patients with recurrent cervical carcinoma. PATIENTS AND METHODS: Ninety patients with recurrent cervical carcinoma and no prior chemotherapy were enrolled onto this study. The median age was 56 years. Eighty-seven of the 90 patients had received prior radiotherapy. The CLD-BOMP regimen was bleomycin 5 mg infused continuously days 1 through 7; vincristine 0.7 mg/m2 bolus day 7; mitomycin 7 mg/m2 bolus day 7; and cisplatin 10 mg/m2 infused over 4 hours days 1 through 7. The treatment was repeated at 3-week intervals. RESULTS: All 90 patients were assessable for response, toxicity, and survival. After a median of four cycles (range, two to 10 cycles), we observed objective responses in 68 patients (76%), with 25 (28%) complete responses (CRs) and 43 (48%) partial responses (PRs; 95% confidence interval (CI), 66 to 85; 18 to 38; 37 to 59, respectively). Median survival for all 90 patients was 24.3 months (range, 2.3 to 100 months). The median survival for patients who achieved CR, PR, no change (NC), and progressive disease (PD) were not reached (NR), 23.6, 8.2, and 6.4 months, respectively. The median progression-free survival for patients who achieved CR and PR were NR and 12.3 months, respectively. There was no significant nausea or vomiting, nephrotoxicity, or pulmonary toxicity, which was attributable to the CLD-cisplatin and the adequate dosing schedule of bleomycin. The reduced toxicities allowed this regimen to be administered at the projected dose-intensities. CONCLUSION: The CLD-BOMP regimen has significant antitumor activity with markedly reduced toxicity.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Neoplasias del Cuello Uterino/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Bleomicina/administración & dosificación , Bleomicina/efectos adversos , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Esquema de Medicación , Femenino , Humanos , Infusiones Intravenosas , Persona de Mediana Edad , Mitomicina/administración & dosificación , Mitomicina/efectos adversos , Análisis Multivariante , Tasa de Supervivencia , Neoplasias del Cuello Uterino/mortalidad , Vincristina/administración & dosificación , Vincristina/efectos adversos
3.
Int J Oncol ; 2(2): 179-84, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21573533

RESUMEN

Thirty-six patients with advanced or recurrent endometrial cancer having had no previous chemotherapy were treated with cisplatin-based chemotherapy. The overall response rate was 38.9%. The mean time to response and the mean duration of response were 9.6 weeks and 16.9 months, respectively. There was no significant difference in response and survival probability between persistent disease and recurrent disease. Size of tumor had a marked influence on response, while age, history of previous irradiation and histologic grade of adenocarcinoma did not affect the response rate. Survival probability by response clearly demonstrated that only complete response exhibited a large impact on survival.

4.
Int J Oncol ; 5(4): 827-31, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21559648

RESUMEN

The effects of human recombinant granulocyte colony-stimulating factor (rhG-CSF) on leukocyte kinetics and immune function were assessed in patients with gynecologic malignancies receiving cytotoxic chemotherapy. Five day-rhG-CSF administration (50 mu g/m(2)/day) increased leukocyte counts in most of the chemotherapy courses. There was a significant difference in the leukocyte increase between the previously irradiated group and the nonirradiated group. An appreciable increase in LAK activity owing to an increased IL-2 production was noted after rhG-CSF administration. Despite a remarkable increase in the neutrophils observed, the CD57(+) cell count and NK activity in peripheral blood mononuclear cells were unexpectedly reduced.

5.
Oncol Rep ; 4(5): 945-8, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-21590172

RESUMEN

The aim of the present study was to evaluate cytotoxic agents active for clear cell carcinoma of the ovary (OCCA) which is intrinsically platinum-resistant. We first conducted in vitro chemosensitivity tests assessing antitumor activities of Various agents against OCCA using two cell lines (HAC-2 and KK) established from ascites of patients with pure OCCA. The most potent single agent was SN-38 (active substance of CPT-11 in vivo) in both cell lines. The second most potent agent was mitomycin-C (MMC) followed by doxorubicin (DOX) in HAC-2 and DOX followed by MMC in KK, respectively. In vivo chemosensitivity test of agents on HAC-2 transplanted into BALB/C nude mice demonstrated that MMC was most potent, followed by DOX and CPT-11. Moreover, a combination of CPT-11 and MMC exhibited the highest anti-tumor activity in this animal model. Cisplatin, etoposide, and paclitaxel were found to be ineffective in either the in vitro or in vivo experimental system. Clinical trial with a combination of MMC and CPT-11 are warranted in patients with OCCA.

6.
Oncol Rep ; 8(4): 767-72, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11410780

RESUMEN

The present study investigated the effect of macrophage colony-stimulating factor (M-CSF) on the immune functions and blood cell counts of patients with ovarian carcinoma receiving cytotoxic chemotherapy (CTX). Seventy-five consecutive patients with white blood cell counts less than 3,000/microl after CTX were randomly assigned to receive either M-CSF (human urinary macrophage colony-stimulating factor: hM-CSF, 8x106 U as 7-day intravenous infusions) or no treatment. Immune assays in addition to routine peripheral blood examinations were performed on these patients at various time points. hM-CSF dosing significantly increased monocyte, lymphocyte, granulocyte, and platelet counts that were decreased by CTX. hM-CSF also significantly enhanced lymphokine-activated killer and natural killer activities, which was accompanied by a significantly augmented interleukin (IL)-2 production. Interestingly, IL-2 production was enhanced by hM-CSF dosing in 24 of the 27 patients with a pre-hM-CSF level of IL-2 below 10 U/ml, but such an effect was not observed in nine of the 10 patients having a basal value of 10 U/ml or higher. Thus, hM-CSF is considered to be a cytokine that can augment or regulate immune functions impaired by CTX and increase blood cell counts that are decreased by CTX.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Recuento de Células Sanguíneas , Células Asesinas Activadas por Linfocinas/inmunología , Factor Estimulante de Colonias de Macrófagos/uso terapéutico , Neoplasias Ováricas/inmunología , Cisplatino/administración & dosificación , Ciclofosfamida/administración & dosificación , Epirrubicina/administración & dosificación , Femenino , Humanos , Infusiones Intravenosas , Interleucina-2/inmunología , Activación de Linfocitos/efectos de los fármacos , Persona de Mediana Edad , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/patología
7.
Oncol Rep ; 5(1): 99-101, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9458301

RESUMEN

The purpose of the present study was to evaluate cytotoxic agents active for mucinous adenocarcinoma of the ovary (MACO) which is considered to be intrinsically platinum-resistant. We first conducted in vitro chemosensitivity tests assessing cytotoxic activities of various anti-cancer agents against MACO using a cell line, designated OMC-3, established from ascites of a patient with histologically pure MACO. The most active single agent was SN-38 (active substance of CPT-11 in vivo). The second most potent agent was mitomycin-C (MMC) followed by doxorubicin (DOX). In vivo chemo-sensitivity test of agents on OMC-3 transplanted into Balb/c nude mice demonstrated that MMC was most potent, followed by DOX. Moreover, a combination of CPT-11 and MMC exhibited the highest anti-tumor activity in this animal model. Cisplatin was found to be ineffective in both the in vitro and in vivo experimental system. Clinical trial with a combination of MMC and CPT-11 are justified in patients with MACO.


Asunto(s)
Adenocarcinoma Mucinoso/tratamiento farmacológico , Antineoplásicos/uso terapéutico , Cisplatino/uso terapéutico , Neoplasias Ováricas/tratamiento farmacológico , Adenocarcinoma Mucinoso/patología , Animales , Antineoplásicos/toxicidad , Antineoplásicos Fitogénicos/uso terapéutico , Antineoplásicos Fitogénicos/toxicidad , Camptotecina/análogos & derivados , Camptotecina/uso terapéutico , Camptotecina/toxicidad , División Celular/efectos de los fármacos , Cisplatino/toxicidad , Doxorrubicina/uso terapéutico , Doxorrubicina/toxicidad , Resistencia a Antineoplásicos , Etopósido/uso terapéutico , Etopósido/toxicidad , Femenino , Humanos , Irinotecán , Ratones , Ratones Desnudos , Mitomicina/uso terapéutico , Mitomicina/toxicidad , Neoplasias Ováricas/patología , Trasplante Heterólogo , Células Tumorales Cultivadas
8.
J Cataract Refract Surg ; 19(3): 371-4, 1993 May.
Artículo en Inglés | MEDLINE | ID: mdl-8501632

RESUMEN

We evaluated the biocompatibility of three kinds of intraocular lenses: heparin-surface-modified, surface-passivated, and regular poly(methyl methacrylate). Each lens type was implanted in 30 eyes. The cases were followed for one year. Biocompatibility was assessed by the degree of postoperative inflammation and capsule opacification. There was no significant difference between the surface-passivated and regular groups on both indices, but there was less postoperative inflammation in the heparin-surface-modified group. The incidence of posterior capsule opacification was greater in the heparin-surface-modified group than in the surface-passivated and regular groups, but the difference was not statistically significant.


Asunto(s)
Catarata/etiología , Heparina , Cápsula del Cristalino/patología , Lentes Intraoculares/efectos adversos , Anciano , Humor Acuoso/metabolismo , Materiales Biocompatibles , Extracción de Catarata , Estudios de Evaluación como Asunto , Fibrina/metabolismo , Estudios de Seguimiento , Humanos , Edema Macular/etiología , Metilmetacrilato , Metilmetacrilatos , Persona de Mediana Edad , Diseño de Prótesis
9.
Carbohydr Res ; 232(2): 273-90, 1992 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-1423360

RESUMEN

5-Deoxy-5-fluoro- (1), 5.3'-dideoxy-5-fluoro- (2), and 5,3',4'-trideoxy-5-fluoro-kanamycin B (3) have been prepared by treatment of 5-epihydroxyl precursors (prepared by the Mitsunobu reaction) with DAST as the key step. 5,3'-Dideoxy-5,5-difluoro- (26) and 5,3',4'-trideoxy-5,5-difluoro-kanamycin B (27) were also prepared by treatment of the corresponding 5-oxo derivatives with DAST. These 5-deoxy-5-fluoro and 5-deoxy-5,5-difluoro derivatives showed markedly decreased toxicity as compared with the parent compounds.


Asunto(s)
Kanamicina/análogos & derivados , Secuencia de Carbohidratos , Kanamicina/síntesis química , Kanamicina/química , Kanamicina/toxicidad , Datos de Secuencia Molecular , Relación Estructura-Actividad
10.
Carbohydr Res ; 49: 141-51, 1976 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-963688

RESUMEN

3',4',-Dideoxykanamycin B, the kanamycin B derivative that is active against resistant bacteria, was prepared from kanamycin B via N-tosylation, 3',4'-O-sulphonylation, 3',4'-unsaturation, and hydrogenation. The unsaturated intermediate was obtained from the 3',4'-di-O-sulphonyl derivatives by the action of sodium iodide in N,N-dimethylformamide; if zinc dust was added in this reaction, aziridine derivatives were formed. Removal of the tosyl group was successfully performed by using sodium in ammonia-ethylamine.


Asunto(s)
Dibekacina/síntesis química , Kanamicina/análogos & derivados , Espectroscopía de Resonancia Magnética , Métodos , Rotación Óptica
11.
Carbohydr Res ; 210: 221-32, 1991 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-1878879

RESUMEN

3'-Deoxy-3'-fluorokanamycin A (14) has been prepared by condensation of 6-azido-2,4-di-O-benzyl-3,6-dideoxy-3-fluoro-alpha-D-glucopyranlsyl++ + bromide (8) and 6-O-(2-O-acetyl-4,6-O-cyclohexylidene-3-deoxy- 3-tosylamino-alpha-D-glucopyranosyl)-2-deoxy-1,3-di-N-tosylstre ptamine (10). Compound 8 was obtained from 3-deoxy-3-fluoro-1,2:5,6-di-O-isopropylidene-D-glucofuranose in seven steps. 3',4'-Dideoxy-3'-fluorokanamycin A (22) has been prepared from 12 through selective 4'-chlorodeoxygenation, a key reaction. Both 14 and 22 were more active than 3'-deoxykanamycin A against both sensitive and resistant bacteria.


Asunto(s)
Antibacterianos/síntesis química , Kanamicina/análogos & derivados , Secuencia de Carbohidratos , Kanamicina/síntesis química , Datos de Secuencia Molecular , Estructura Molecular
12.
Carbohydr Res ; 238: 147-62, 1993 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-8431932

RESUMEN

5-Deoxy-5-fluoro- (9) and 5-deoxy-5,5-difluoro-netilmicin (27) have been prepared from the corresponding 5-epi and 5-oxo derivatives of netilmicin by treatment with DAST. Structures of the fluorinated by-products (10, 11, and 12) obtained in one of the synthesis of 9 were determined. 5-Epi-netilmicin (13) and 5-epi-6'-N-methyl-netilmicin (21) have also been prepared.


Asunto(s)
Netilmicina/análogos & derivados , Netilmicina/síntesis química , Animales , Secuencia de Carbohidratos , Relación Dosis-Respuesta a Droga , Dosificación Letal Mediana , Ratones , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , Netilmicina/toxicidad
13.
Carbohydr Res ; 169: 69-81, 1987 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-3427590

RESUMEN

The title compounds (17 and 23) were prepared by coupling 3,4-di-O-acetyl-2,6-dideoxy-2-fluoro-alpha-L-talopyranosyl bromide (15) with daunomycinone. The key step in the preparation of 15 was the epoxide-ring opening of methyl 2,3-anhydro-4-O-benzyl-6-deoxy-alpha-L-gulopyranoside with KHF2 in ethylene glycol, whereupon 2-fluoro-alpha-L-idopyranoside was obtained. Compounds 17 and 23 showed strong antitumor activity.


Asunto(s)
Antibióticos Antineoplásicos/síntesis química , Daunorrubicina/análogos & derivados , Doxorrubicina/análogos & derivados , Animales , Daunorrubicina/síntesis química , Daunorrubicina/uso terapéutico , Daunorrubicina/toxicidad , Doxorrubicina/síntesis química , Doxorrubicina/uso terapéutico , Doxorrubicina/toxicidad , Indicadores y Reactivos , Leucemia L1210/tratamiento farmacológico , Espectroscopía de Resonancia Magnética , Ratones , Rotación Óptica , Relación Estructura-Actividad
14.
Carbohydr Res ; 232(1): 89-105, 1992 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-1423353

RESUMEN

4'-Deoxy-4'-fluorokanamycins A (17) and B (25) have been prepared through fluorinative ring-opening of the D-galacto-3',4'-oxiranes (8 and 21) derived from kanamycin A and B with potassium hydrogenfluoride in ethane-1,2-diol. The mechanism of preponderant formation of the 4'-deoxy-4'-fluoro-D-gluco (9 and 22) over the 3'-deoxy-3'-fluoro-D-gulo derivatives was discussed. In the synthesis of 25, the unusual 3',6'-epimine (23) was the main product along with the 4'-deoxy-4'-fluoro derivative. The mechanism of this reaction is also discussed. Both 17 and 25 were active against resistant bacteria producing aminoglycoside-adenylylating enzymes for HO-4'.


Asunto(s)
Antibacterianos/síntesis química , Kanamicina/síntesis química , Antibacterianos/química , Secuencia de Carbohidratos , Kanamicina/química , Datos de Secuencia Molecular
15.
J Antibiot (Tokyo) ; 41(4): 530-7, 1988 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3372360

RESUMEN

1-N-(D-Threo-3-amino-2-hydroxybutanoyl)-2',3'-dideoxykanamycin+ ++ A has been prepared by coupling of 3,6'-bis(N-benzyloxycarbonyl)-2',3'-dideoxy-3"-N-(trifluoroacetyl)kanamy cin A with D-threo-3-azido-2-hydroxybutanoic acid. A diastereomeric mixture of the erythro analog has also been prepared by use of racemic erythro-3-azido-2-hydroxybutanoic acid. Synthesis of the D-threo- and racemic erythro-3-amino-2-hydroxybutanoic acids has been described.


Asunto(s)
Antibacterianos/síntesis química , Kanamicina/análogos & derivados , Antibacterianos/farmacología , Kanamicina/síntesis química , Kanamicina/farmacología , Estereoisomerismo , Relación Estructura-Actividad
16.
J Antibiot (Tokyo) ; 31(10): 991-6, 1978 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-81828

RESUMEN

1-Deamidino-, 3-deamidino- and 1,3-di(deamidino)dihydrostreptomycin (1, 2, 3) were prepared by treatment of dihydrostreptomycin (DHSM) with ammonia at 100 degrees C. The 3-guanidino group of DHSM is suggested to be more important than the 1-guanidino group for the antibacterial activity of DHSM. 1-N-[(S)-4-Amino-2-hydroxybutyryl) and 1-N-[(S)-4-guanidino-2-hydroxybutyryl] derivatives (4, 6) of 1-deamidinodihydrostreptomycin were futher prepared.


Asunto(s)
Sulfato de Dihidroestreptomicina/análogos & derivados , Acilación , Bacterias/efectos de los fármacos , Fenómenos Químicos , Química , Sulfato de Dihidroestreptomicina/síntesis química , Sulfato de Dihidroestreptomicina/farmacología , Farmacorresistencia Microbiana
17.
J Antibiot (Tokyo) ; 30(1): 71-5, 1977 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-838633

RESUMEN

The first synthesis of 6'-C-aminomethyl derivatives (6'-epimers) of 3'-deoxyparomamine is reported starting from 3'-deoxyparomamine by way of 6'-O-tritylation, O-acetylation, hydrolysis of the trityl group, conversion of the 6'-hydroxyl group into an aldehyde group, nitromethane condensation of the aldehyde group and catalytic reduction of the nitro group into an amino group.


Asunto(s)
Aminoglicósidos/síntesis química , Antibacterianos/síntesis química , Acetilación , Aminoglicósidos/farmacología , Bacterias/efectos de los fármacos , Fenómenos Químicos , Química , Hidrólisis , Oxidación-Reducción
18.
J Antibiot (Tokyo) ; 31(12): 1233-7, 1978 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-83983

RESUMEN

A key protected streptidine derivative (3) useful for the synthesis of antibiotics of streptomycin series was prepared by hydrolysis of an acylated dihydrostreptomycin (DHSM) derivative (2), and it was condensed with a protected dihydrostreptobiosaminyl chloride (5) to give two condensation products (6 and 7). By deblocking, 6 was led to DHSM and 7 to a biologically inactive isomer (8) of DHSM. From the PMR spectrum of 4-O-mesyl derivative (4) of 3, the benzyloxycarbonyl and acetyl groups were concluded to be attached to the end nitrogens of the guanidine groups.


Asunto(s)
Sulfato de Dihidroestreptomicina/síntesis química , Fenómenos Químicos , Química , Cromatografía en Capa Delgada , Sulfato de Dihidroestreptomicina/farmacología , Hidrólisis , Estereoisomerismo
19.
J Antibiot (Tokyo) ; 46(8): 1265-78, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8407589

RESUMEN

The 3-deoxy-3,4-didehydro derivatives of 5-O-mycaminosyltylonolide, 5-O-(4-deoxymycaminosyl)tylonolide, and desmycosin have been prepared by treatment of the corresponding 3-O-sulfonyl derivatives with NaI in 2-butanone as the key step. The mechanistic difference in the formation of the 2,3- and 3,4-unsaturated derivatives from the same 3-O-sulfonyl derivative is discussed.


Asunto(s)
Antibacterianos/síntesis química , Tilosina/análogos & derivados , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Tilosina/síntesis química , Tilosina/farmacología
20.
J Antibiot (Tokyo) ; 40(4): 476-82, 1987 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3583916

RESUMEN

Several derivatives of 5-O-mycaminosyltylonolide substituted at C-23 have been prepared; these are 23-deoxy-23-C-methylene (3), 23-deoxy-23-C-(methoxycarbonylmethylene) (5), 23-deoxy-23-C-(ethoxycarbonylmethylene) (7), and 23-deoxy-23-C-(butoxycarbonylmethylene) (9), 23-deoxy-23-C-[(2E)-3-(ethoxycarbonyl)-2-propenylene] (11), and 23-deoxy-23-(dimethylaminoimino) (13), and 14-de(hydroxymethyl)-14-nitrile (16) derivatives. The key steps in these syntheses are the reactions of 2',4'-di-O-acetyl-3-O-tert-butyldimethylsilyl-23-deoxy-23-oxo-5-O- mycaminosyltylonolide diethyl acetal (1) with several Wittig reagents, 1,1-dimethylhydrazine and hydroxylamine. Antibacterial activities of these compounds are also described.


Asunto(s)
Antibacterianos/síntesis química , Leucomicinas , Bacterias/efectos de los fármacos , Indicadores y Reactivos , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Rotación Óptica , Relación Estructura-Actividad
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