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1.
Chirality ; 33(8): 454-464, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33987900

RESUMO

New two catalysts component system comprising of a primary ß-amino silyl ethers as an organocatalyst and N-protected amino acids as a co-catalyst put together worked as an efficient organocatalyst system in the hetero Diels-Alder reaction of isatins with enones affording the chiral spirooxindole-tetrahydropyranones in good chemical yields and stereoselectivities (up to 94%, up to dr 78:22., up to 85% ee).

2.
Artigo em Inglês | MEDLINE | ID: mdl-26460321

RESUMO

BABYSCAN, a whole-body counter (WBC) for small children was developed in 2013, and units have been installed at three hospitals in Fukushima Prefecture. Between December, 2013 and March, 2015, 2707 children between the ages of 0 and 11 have been scanned, and none had detectable levels of radioactive cesium. The minimum detectable activities (MDAs) for (137)Cs were ≤ 3.5 Bq kg(-1) for ages 0-1, decreasing to ≤ 2 Bq kg(-1) for ages 10-11. Including the (134)Cs contribution, these translate to a maximum committed effective dose of ∼ 16 µSv y(-1) even for newborn babies, and therefore the internal exposure risks can be considered negligibly small.Analysis of the questionnaire filled out by the parents of the scanned children regarding their families' food and water consumption revealed that the majority of children residing in the town of Miharu regularly consume local or home-grown rice and vegetables, while in Minamisoma, a majority avoid tap water and produce from Fukushima. The data show, however, no correlation between consumption of locally produced food and water and the children's body burdens.


Assuntos
Acidente Nuclear de Fukushima , Monitoramento de Radiação , Inquéritos e Questionários , Contagem Corporal Total , Distribuição por Idade , Criança , Pré-Escolar , Feminino , Hospitais/estatística & dados numéricos , Humanos , Lactente , Recém-Nascido , Masculino , Fatores de Tempo
3.
RSC Adv ; 13(2): 888-894, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36686933

RESUMO

Distinct types of new boron fused primary amino amide organocatalysts were designed and synthesized from commercially available amino acids. Their catalytic activities were investigated in asymmetric crossed aldol reaction of ketones with aromatic aldehydes to afford the corresponding chiral anti-aldol adducts with good chemical yields, moderate diastereoselectivity and good to excellent enantioselectivities (up to 94% yields, up to 90 : 10 dr, up to 94% ee).

4.
RSC Adv ; 13(6): 3715-3722, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36756606

RESUMO

Catalytic functionality of new optically active thiourea fused γ-amino alcohols was examined in the asymmetric Mannich reaction of ß-keto active methylene compounds with imines to afford chiral Mannich products, ß-amino keto compounds, with continuous chiral centers, that are versatile synthetic intermediates for deriving various biologically active compounds. In particular, the thiourea fused γ-amino alcohols showed satisfactory catalytic activity in this reaction and afforded chiral Mannich products in excellent chemical yield (up to 88%) and stereoselectivities (up to syn : anti/93 : 7 dr, up to 99% ee).

5.
RSC Adv ; 11(61): 38925-38932, 2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-35493209

RESUMO

New small γ-turn type N-primary amino terminal tripeptides were synthesized and their functionality as an organocatalyst was examined in the asymmetric aldol reaction of various ketones with different aromatic aldehydes under solvent-free neat conditions to afford the desired chiral anti-aldol products in good to excellent chemical yields, diastereoselectivities and enantioselectivities (up to 99%, up to syn : anti/13 : 87 dr, up to 99% ee).

6.
RSC Adv ; 11(1): 203-209, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-35423042

RESUMO

Simple primary ß-amino alcohols act as an efficient organocatalysts in the asymmetric Michael addition of ß-keto esters with nitroalkenes affording highly pure chiral Michael adducts. Also, both enantiomers of the adducts were obtained, depending on the specific catalyst used and reaction temperature.

7.
RSC Adv ; 10(30): 17486-17491, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35515584

RESUMO

A simple two catalyst component system consisting of primary ß-amino alcohols as a catalyst and amino acids as a co-catalyst put together works as an efficient organocatalyst system in the hetero Diels-Alder reaction of isatins with enones to afford the chiral spirooxindole-tetrahydropyranones in good chemical yields and stereoselectivities (up to 86%, up to 85 : 15 dr., up to 95% ee).

8.
ACS Omega ; 3(9): 11718-11726, 2018 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31459268

RESUMO

The new hybrid-type squaramide-fused amino alcohol containing both a Brønsted basic site and hydrogen-bonding sites in the molecule showed a high catalytic activity as an organocatalyst in the enantioselective domino Michael addition/cyclization reaction of oxoindolines with cyclic 1,3-diketones to afford the chiral spiro-conjugated oxindoles featuring 2-aminopyrans fusing with carbo-heterocyclic ring systems with excellent chemical yields (up to 98%) and enantioselectivities (up to 95% ee). The obtained chiral spiro-conjugated 2-aminopyrans bearing quaternary stereogenic carbon center could be used as synthetic precursors for several natural products that have a broad spectrum of fascinating biological activities.

9.
BMJ Open ; 5(12): e009745, 2015 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-26644125

RESUMO

OBJECTIVE: To assess internal radiocontamination of patients with end-stage renal disease (ESRD) who were regularly taking haemodialysis (HD) and living in areas affected by the crippled Fukushima Daiichi nuclear plant after the Great East Japan earthquake on 11 March 2011. METHODS: Internal radiocontamination in 111 patients with ESRD regularly taking HD at Jyoban Hospital in Iwaki city, Fukushima from July 2012 to November 2012 was assessed with a whole body counter (WBC). The maximum annual effective dose was calculated from the detected Cs-137 levels. Interviews concerning patient dietary preferences and outdoor activities were also conducted. RESULTS: Among the 111 patients tested, internal radiocontamination with Cs-137 was detected in two participants, but the levels were marginal and just exceeded the detection limit (250 Bq/body). The tentatively calculated maximum annual effective dose ranged from 0.008 to 0.009 mSv/year, which is far below the 1 mSv/year limit set by the government of Japan. Relative to 238 non-ESRD participants, patients with ERSD had significantly more opportunities to consume locally grown produce that was not distributed to the market (p<0.01). However, the percentage of patients with ESRD with detectable Cs (1.8%) was lower than that for non-ESRD participants (3.8%), although this difference was not significant (p=0.51). CONCLUSIONS: These findings suggest that internal radiocontamination levels and the calculated annual additional effective doses were negligible for patients with ESRD taking HD in areas affected by the crippled Fukushima nuclear plant. Although HD is suggested to promote Cs-137 excretion, continuous inspection of locally grown produce together with WBC screening for radiocontamination should be continued for patients with ESRD regularly taking HD.


Assuntos
Radioisótopos de Césio/análise , Acidente Nuclear de Fukushima , Falência Renal Crônica/terapia , Exposição à Radiação/análise , Contagem Corporal Total/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Desastres , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Diálise Renal , Estudos Retrospectivos
10.
PLoS One ; 10(10): e0140482, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26484532

RESUMO

Following the Fukushima nuclear power plant disaster, assessment of internal radiation exposure was indispensable to predict radiation-related health threats to residents of neighboring areas. Although many evaluations of internal radiation in residents living north and west of the crippled Fukushima nuclear power plant are available, there is little information on residents living in areas south of the plant, which were similarly affected by radio-contamination from the disaster. To assess the internal radio-contamination in residents living in affected areas to the south of the plant or who were evacuated into Iwaki city, a whole body counter (WBC) screening program of internal radio-contamination was performed on visitors to the Jyoban hospital in Iwaki city, which experienced less contamination than southern areas adjacent to the nuclear plant. The study included 9,206 volunteer subjects, of whom 6,446 were schoolchildren aged 4-15 years. Measurements began one year after the incident and were carried out over the course of two years. Early in the screening period only two schoolchildren showed Cs-137 levels that were over the detection limit (250 Bq/body), although their Cs-134 levels were below the detection limit (220 Bq/body). Among the 2,760 adults tested, 35 (1.3%) had detectable internal radio-contamination, but only for Cs-137 (range: 250 Bq/body to 859 Bq/body), and not Cs-134. Of these 35 subjects, nearly all (34/35) showed elevated Cs-137 levels only during the first year of the screening. With the exception of potassium 40, no other radionuclides were detected during the screening period. The maximum annual effective dose calculated from the detected Cs-137 levels was 0.029 and 0.028 mSv/year for the schoolchildren and adults, respectively, which is far below the 1 mSv/year limit set by the government of Japan. Although the data for radiation exposure during the most critical first year after the incident are unavailable due to a lack of systemic measurements, the present results suggest that internal radio-contamination levels more than one year after the incident were minimal for residents living south of the crippled Fukushima nuclear plant, and that the annual additional effective doses derived from internal Cs contamination were negligible. Thus, internal radio-contamination of residents living in southern radio-contaminated areas appears to be generally well controlled.


Assuntos
Desastres , Exposição Ambiental/análise , Acidente Nuclear de Fukushima , Monitoramento de Radiação/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Radioisótopos de Césio/análise , Criança , Pré-Escolar , Exposição Ambiental/prevenção & controle , Feminino , Geografia , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Centrais Nucleares , Doses de Radiação , Contagem Corporal Total/instrumentação , Contagem Corporal Total/métodos
12.
Clin Transplant ; 16 Suppl 8: 62-7, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12464135

RESUMO

A 61-year-old-woman with end-stage renal disease caused by IgA nephropathy received living unrelated kidney transplantation from her husband in February 2001. Pre-transplant donor-specific T- and B-cell cross-match was negative. Immunosuppressive treatment consisted of tacrolimus (TAC), mycophenolate mofetil (MMF), methylprednisolone (MP) and antilymphocyte globulin (ALG). The kidney functioned immediately after kidney transplantation. On post-operative day 9, the level of serum creatinine (S-Cr) rose from 1.1 to 1.5 mg/dL. The allograft biopsy specimen taken on the day revealed moderate accumulations of polymorphonuclear leucocytes in peritubular capillaries (PTCs), dilatation of PTCs and transplant glomerulitis, moderate to severe. Immunofluorescent study of a frozen section of the allograft biopsy specimen showed a strong, diffusely distributed endothelial staining pattern in PTCs for the stable complement split product C4d. Post-transplant donor-specific T- and B-cell cross-matches performed on post-operative day 13 were positive. From the allograft biopsy and the positive post-transplant donor-specific T- and B-cell cross-matching, acute humoral rejection (AHR) associated with the development of antidonor antibodies (ADA) was diagnosed. Plasma exchange (PE) treatment was initiated on day 11. After a total of 13 treatments of PE, donor-specific T- and B-cell cross-matches became negative and the biopsy performed on day 72 revealed mild transplant glomerulopathy without accumulation of polymorphonuclear leucocytes in PTCs or a C4d staining pattern in PTCs of immunofluorescence. The allograft functioned well and the creatinine level was 1.1 mg/dL 7 months post-transplant. This was a case of AHR after renal transplantation associated with the development of ADA, which was triggered by spousal-donor antigens. The presence of widespread C4d deposition in PTCs in renal allograft biopsies played a role in the diagnosis of AHR and the diagnosis was confirmed by positive donor-specific T- and B-cell cross-matches at the time of rejection, which were negative at pre-transplantation. Several treatments of PE were effective for resolving AHR in this case and the effect of PE in the treatment of AHR could be assessed by the degree of peritubular capillaritis (PTCitis) and C4d deposits in PTCs.


Assuntos
Anticorpos/sangue , Complemento C4b , Rejeição de Enxerto/imunologia , Transplante de Rim/imunologia , Rim/imunologia , Rim/patologia , Formação de Anticorpos , Linfócitos B/imunologia , Biópsia , Complemento C4/análise , Feminino , Glomerulonefrite por IGA/cirurgia , Rejeição de Enxerto/patologia , Rejeição de Enxerto/terapia , Teste de Histocompatibilidade , Humanos , Pessoa de Meia-Idade , Fragmentos de Peptídeos/análise , Troca Plasmática , Linfócitos T/imunologia , Doadores de Tecidos
13.
Clin Transplant ; 17 Suppl 10: 9-13, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12823250

RESUMO

We examined histological features of allograft biopsies in ABO minor-mismatched kidney transplantation. Forty-five patients who underwent ABO minor-mismatched kidney transplantation between September 1999 and December 2001 at our institute. The mean age was 32.6 years, with 28 males and 17 females. We divided them into five groups based on the donor and recipient ABO blood groups. Group 1, O renal allografts given to A patients (13 patients); Group 2, O to B (9), Group 3, O to AB (2); Group 4, A to AB (9); and Group 5, B to AB (12). From September 1999 to April 2002, we performed 127 allograft biopsies in these 45 ABO minor-mismatched kidney transplant recipients. Among a total of 127 biopsy specimens, 47 specimens were taken as 0- or 1-h biopsies and 6 were protocol biopsies. Pathological analysis of 74 episode biopsy specimens showed: acute humoral rejection (AHR) in 13 (18%); acute cellular rejection (ACR) in 17 (23%); combined AHR and ACR in eight (11%); borderline change in six (8%); chronic rejection in 10 (12%); cyclosporin or tacrolimus nephrotoxicity in seven (10%) and chronic allograft nephropathy in three (4%). In total, some form of acute rejection (AR) was seen histologically in 38 biopsy specimens (48%) from 19 patients (42%). When we investigated AR in two separate categories, i.e. AHR and ACR, AHR was diagnosed in 21 biopsy specimens (26%) from 15 patients (33%) and ACR was seen in 25 biopsy specimens (31%) from 13 patients (29%). We compared the incidence rate of acute rejection in the cases of ABO minor-mismatched renal transplantation with ABO-incompatible and ABO-compatible cases between January 1989 and December 1999. The incidence rate of AR in ABO minor-mismatched cases (42%) was statistically lower than that in ABO-incompatible cases (63%). There was no statistical difference in the incidence rate of AR between ABO minor-mismatched cases and ABO-compatible cases (49%). There was statistical difference in the incidence of AR among the donor and recipient ABO blood groups. Group 4 (A allografts given to AB patients) had the statistically highest rate of AR (89%), followed by Group 1 (54%), Group 5 (33%) and Group 2 (11%), and there was no AR case in Group 3 (O to AB). In conclusion, the incidence rate of AR in ABO minor-mismatched kidney transplantation is statistically lower than ABO-incompatible cases and is not statistically different from that in ABO-compatible cases. The incidence cases of AHR are slightly higher than that of ACR in ABO minor-mismatched kidney transplantation and this finding is similar to findings of ABO incompatible kidney transplantation. Finally, there is a statistical difference in AR incidence among the donor and recipient ABO blood groups.


Assuntos
Sistema ABO de Grupos Sanguíneos/imunologia , Rejeição de Enxerto/imunologia , Teste de Histocompatibilidade/métodos , Transplante de Rim/imunologia , Transplante de Rim/métodos , Rim/patologia , Transplantes , Adolescente , Adulto , Idoso , Biópsia , Criança , Pré-Escolar , Feminino , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/patologia , Histocompatibilidade/imunologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade
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