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61.
62.
We retrospectively investigated clinical outcomes and prognostic factors of 131 patients with transplant-ineligible newly diagnosed multiple myeloma (NDMM) who received melphalan and prednisolone (MP) as first-line therapy from 2006 to 2013. Eighty-one patients received salvage therapies incorporating bortezomib, lenalidomide, and/or thalidomide. The overall response rate to MP was 54.2 %, including 9.2 % of better than very good partial response. With a median follow-up period of 30.2 months, median overall survival (OS) and median time to next treatment (TNT) were 54.4 and 19.0 months, respectively. Univariate analysis revealed that performance status and serum calcium level significantly associated with both OS and TNT, and multivariate analysis revealed that the higher serum calcium level had a significantly unfavorable impact on OS and TNT. Importantly, staging informed by the international staging system (ISS) was not predictive for OS or TNT in the analyzed cohort. Our study revealed that, in the context of first-line MP therapy for NDMM, the salvage therapy incorporating novel agents produced a survival period of >30 months after the initiation of second-line therapy, suggesting that the predictive value of ISS for OS and TNT may be limited in the era of novel agents.  相似文献   
63.
AIM: To evaluate the role of N-myc downstream-regulated gene 1 (NDRG1) expression in prognosis and survival of colorectal cancer patients with different ethnic backgrounds. METHODS: Because NDRG1 is a downstream target of p53 and hypoxia inducible factor-1α (HIF-1α),we examined NDRG1 expression together with p53 and HIF-1α by immunohistochemistry. A total of 157 colorectal cancer specimens including 80 from Japanese patients and 77 from US patients were examined. The correlation between protein expression with clinicopathological features and survival after surgery was analyzed.in colorectal tumor compared with normal epithelium in both Japanese and US patient groups. Expression of NDRG1 protein was significantly correlated with lymphatic invasion,venous invasion,depth of invasion,histopathological type,and Dukes' stage in Japanese colorectal cancer patients. NDRG1 expression was correlated to histopathological type,Dukes' stage and HIF-1α expression in US-Caucasian patients but not in US-African American patients. Interestingly,Kaplan-Meier survival analysis demonstrated that NDRG1 expression correlated significantly with poorer survival in US-African American patients but not in other patient groups. However,in p53-positive US cases,NDRG1 positivity correlated significantly with better survival. In addition,NDRG1 expression also correlated significantly with improved survival in US patients with stages Ⅲ and Ⅳ tumors without chemotherapy. In Japanese patients with stages Ⅱ and Ⅲ tumors,strong NDRG1 staining in p53-positive tumors correlated significantly with improved survival but negatively in patients without chemotherapy. CONCLUSION: NDRG1 expression was correlated with various clinicopathological features and clinical outcomes in colorectal cancer depending on the race/ethnicity of the patients. NDRG1 may serve as a biological basis for the disparity of clinical outcomes of colorectal cancer patients with different ethnic backgrounds.  相似文献   
64.
Detection of lacunar infarcts is important because their presence indicates an increased risk of severe cerebral infarction. However, accurate identification is often hindered by the difficulty in distinguishing between lacunar infarcts and enlarged Virchow-Robin spaces. Therefore, we developed a computer-aided detection (CAD) scheme for the detection of lacunar infarcts. Although our previous CAD method indicated a sensitivity of 96.8 % with 0.71 false positives (FPs) per slice, further reduction of FPs remained an issue for the clinical application. Thus, the purpose of this study is to improve our CAD scheme by using template matching in the eigenspace. Conventional template matching is useful for the reduction of FPs, but it has the following two pitfalls: (1) It needs to maintain a large number of templates to improve the detection performance, and (2) calculation of the cross-correlation coefficient with these templates is time consuming. To solve these problems, we used template matching in the lower dimension space made by a principal component analysis. Our database comprised 1,143 T1- and T2-weighted images obtained from 132 patients. The proposed method was evaluated by using twofold cross-validation. By using this method, 34.1 % of FPs was eliminated compared with our previous method. The final performance indicated that the sensitivity of the detection of lacunar infarcts was 96.8 % with 0.47 FPs per slice. Therefore, the modified CAD scheme could improve FP rate without a significant reduction in the true positive rate.  相似文献   
65.
Cytolethal distending toxins (CDTs) are inhibitory cyclomodulins, which block eukaryotic cell proliferation and are produced by a diverse group of Gram-negative bacteria, including Escherichia coli strains associated with intestinal and extraintestinal infections. However, the mode of transmission of the toxin gene clusters among diverse bacterial pathogens is unclear. We found that Cdt-I produced by enteropathogenic E. coli strains associated with diarrhea is encoded by a lambdoid prophage, which is inducible and infectious. The genome of Cdt-I converting phage (CDT-1Phi) comprises 47,021 nucleotides with 60 predicted ORFs organized into six genomic regions encoding the head and tail, virulence, integrase, unknown functions, regulation, and lysis. The genomic organization of CDT-1Phi is similar to those of SfV, a serotype-converting phage of Shigella flexneri, and UTI89, a prophage identified in uropathogenic E. coli. Besides the cdtI gene cluster, the virulence region of CDT-1Phi genome contains sequences homologous to a truncated cycle inhibiting factor and a type 3 effector protein. Mutation analysis of susceptible E. coli strain C600 suggested that the outer membrane protein OmpC is a putative receptor for CDT-1Phi. CDT-1Phi genome was also found to integrate into the host bacterial chromosome forming lysogens, which produced biologically active Cdt-I. Furthermore, phage induction appeared to cause enhanced toxigenicity of the E. coli strains carrying lysogenic CDT-1Phi. Our results suggest that CDT-1Phi is the latest member of a growing family of lambdoid phages encoding bacterial cyclomodulins and that the phage may have a role in horizontal transfer of these virulence genes.  相似文献   
66.
Dipylidium caninum, the dog tapeworm, is a common intestinal cestode of domestic dogs and cats, but few cases have been reported of human infection by this parasite in Japan. We repot a case of D. caninum infection in a 17 month-old girl, who sometimes had symptoms of abdominal pain, diarrhea, and dysphoria at night. Her mother noted the appearance of small white worms in her stool, and she was seen by a local pediatrician. Despite antiparasitic therapy wiht pyrantel pamoate, the problem persisted and was eventually referred for further workup to Kurume University Hospital. The diagnosis was made by microscopic examination of the excreted proglottids, which contained characteristic egg capsules. She was successfully treated with a singledose of praziquantel and four adult parasites were recovered. The longest intact worm was 32cm. Her family had household pets (a dog and a cat). The pets were seen by the local veterinary and both were evidenced D. caninum. Humans, primarily children, become infected when they accidentally ingest fleas. Parents usually find proglottids as multiple white objects, often described as cucumber, melon, or pumpkin seeds, in stool, diapers, or on the perineum. Most general practitioners and pediatricians may treat children with enterobiasis (pinworm) infection, and in case the treatment fails, other parasite infection should be considered such as this worm. A history of dog or cat pets, fleas, and flea bites may be important clues to diagnosis. Pets found to be infected should also be treated.  相似文献   
67.
    
In this study, in situ catalytically generated allylic indium from 1,3 dienes and InCl2H was developed for use in the allylation of ketones. This protocol resulted in the unprecedented establishment of a successive combining of quaternary C–C bonds, which could then be applied to many types of ketones. Other branched 1,3 dienes and vinyl cyclopropanes, could also be coupled with ketones in a reaction where CuH would not be applicable.

In this study, in situ catalytically generated allylic indium from 1,3 dienes and InCl2H was developed for use in the allylation of ketones.

Homoallylic alcohols are useful building blocks in the synthesis of bioactive natural compounds and pharmaceuticals. For these syntheses, the preparation of tertiary compounds has remained challenging regardless of whether or not they are given asymmetrically.1 The allylation of ketones with allylic reagents is a typical method for the preparation of these compounds (Scheme 1a).2 This method, however, cannot avoid wasteful steps such as the transmetalation between Grignard reagents and B, Si or Sn sources and the reductive generation between allylic halides and low-valent metals. Although this method can be applied to highly stereocontrolled reactions, the wasteful steps are cumbersome and more practical reaction methods are required.Open in a separate windowScheme 1Synthesis of homoallylic alcohols from allylation reagents with ketones.For this process, 1,3-dienes are an important industrial feedstock that is produced on a massive scale via either the cracking of ethylenes or the transformation of biomass. Easily available dienes have recently replaced the conventional allylation of aldehydes with the aid of transition metal catalysts (Scheme 1b).3 After the first application using a Ti catalyst by Gendre and Moïse,4 Krische has expanded the field with the introduction of Ru-catalyzed stereocontrolled reactions.5 Other transition metals such as Ni,6 Ir,7 and Rh8 have contributed to improvements in coupling. A recent adoption of ketones as viable substrates was achieved by Liu and Buchwald via proficient Cu–H chemistry.9 The scope of possible substrates could be expanded even further,10 however, particularly with the use of 1,3-dienes and ketones that possess a variety of functional groups.Our group has explored the hydrostannylation11 or indation12 of unsaturated bonds in the preparation of reactive organostannanes or indiums that could be applied to further transformations, although stoichiometric amounts of Sn or In sources must be added to the reaction systems. Recently, a transition metal-free reductive coupling of 1,3-dienes,13 or their derivatives such as vinyl cyclopropanes,14 with aldehydes catalyzed by Bu2SnXH has been developed, but the method would not allow the use of ketones due to the low reactivity of the reaction intermediate, allylic stannanes (Scheme 1c). On the other hand, our group has already developed a process for the hydroindation of 1,3-dienes with a stoichiometric amount of InX2H to give allylic indiums followed by the allylation of ketones.12b,12d Herein, we report the catalytic coupling of 1,3-dienes or vinyl cyclopropanes with ketones through the generation of allylic indiums via the hydroindation of 1,3-dienes with a catalytic amount of InX2H (Scheme 1c).We initiated the optimization of the reaction conditions by combining 1,3-butadiene (1a) and acetophenone (2a) in a sealed test tube (Table 1). The gaseous diene 1a was liquefied and weighed before addition to the reaction. Based on our previous reports, InCl2OMe generated from InCl3/NaOMe and a silane were chosen as indium and hydride sources, respectively.13 The desired product 3aa was obtained in a 92% yield as a mixture of the diastereomers (entry 1). The yield was lowered either when no MeOH was used or when the reaction time was cut by half (entries 2 and 3). A screening of the silanes showed that MePhSiH2 was the optimal hydride source (entries 4–7). We found that the reaction was finished in 3 h when the reaction temperature was raised to 60 °C (entry 8). Replacing the solvent with MeCN, Et2O or toluene did not improve the reaction yield (entries 9–11). It was necessary to add NaOMe to the reaction system for a facile generation of InCl2H (entry 12).16 It was important to add InCl3 to the reaction (entry 13). A radical scavenger, TEMPO, suppressed the progress of the reaction, which implied that this reaction contains a radical process (entry 14). The reaction yield was decreased when the lower amount of the catalyst was employed (entry 15).Optimization of the reaction conditionsa
EntrySilaneSolventConditionsYield (%)3aa (syn : anti)b
1MePhSiH2THF25 °C, 48 h92 (80 : 20)
225 °C, 48 h w/o MeOH42 (88 : 12)
325 °C, 24 h w/o MeOH54 (76 : 24)
4Et3SiHTHF25 °C, 24 h12c
5Ph3SiHTHF25 °C, 24 h0
6Ph2SiH2THF25 °C, 24 h32 (83 : 17)
7PhSiH3THF25 °C, 24 h54 (83 : 17)
8MePhSiH2THF60 °C, 3 h92 (80 : 20)
9MeCN38 (80 : 20)
10Et2O71 (76 : 42)
11Toluene9c
12THFw/o NaOMeTrace
13w/o InCl30
14With TEMPO (0.2 mmol)0
15With InCl2OMe (0.1 mmol)51 (78 : 22)
Open in a separate windowaThe yields were determined by 1H NMR.bStereochemistry, see: ref. 15.cdr could not be determined because of complex of the reaction mixture.With the optimal reaction conditions in hand (Table 1, entry 8), the scope of the ketones was investigated (Table 2). Electron-deficient substitution on the phenyl ring had a small effect on the reaction yield, but an electron-rich substitution decreased it appreciably (entries 2–6). The efficiency was also attenuated by steric hindrance around the C Created by potrace 1.16, written by Peter Selinger 2001-2019 O moiety of propiophenone (2g) and butyrophenone (2h) (entries 7 and 8). α-Cyano and -bromo acetophenone 2i and 2j, respectively, reacted sufficiently (entries 9 and 10). The tolerance to reduction of the C–Br bond by InX2H under reductive conditions is a characteristic of coupling (entries 3 and 10).17 On the other hand, α-methoxy one was unsatisfactory as a reactant probably due to chelation between the OMe and C Created by potrace 1.16, written by Peter Selinger 2001-2019 O groups with the catalyst that would have promoted a reduction in the ketone 2k (entry 11). β-Keto ester 2l was a good partner even though a similar chelation involving two C Created by potrace 1.16, written by Peter Selinger 2001-2019 O groups could have happened (entry 12). Both acyclic and cyclic aliphatic ketones were allylated (entries 13–14). Other aromatic rings such as naphthalenes were introduced into the products 3ao and 3ap (entries 15 and 16).Scope of ketonesa
EntryR1R2KetoneProductYield (%) (dr)
1C6H5Me2a3aa92 (80 : 20)
2 p-ClC6H42b3ab83 (79 : 21)
3 p-BrC6H42c3ac88 (80 : 20)
4 p-CNC6H42d3ad79 (79 : 21)
5 p-MeC6H42e3ae53 (75 : 25)
6 p-OMeC6H42f3af58 (75 : 25)
7C6H5Et2g3ag69 (84 : 16)
8 n Pr2h3ah66 (84 : 16)
9CH2CN2i3ai75 (82 : 18)
10CH2Br2j3aj74 (84 : 16)
11CH2OMe2k3ak22 (80 : 20)
12CH2CO2Et2l3al59 (80 : 20)
13bPhCH2CH2–(CH2)5Me2m3am73 (57 : 43)
142n3an75
151-NpMe2o3ao77 (75 : 25)
162-NpMe2p3ap80 (76 : 24)
Open in a separate windowaThe yields were determined by 1H NMR.bReaction time was 24 h.Reductive coupling was then applied to other dienes (Scheme 2). In the case of isoprene (1b), two different products, 3ba and 3ba′, were formed even though the reaction was very slow (eqn (1)). The regioselectivity derived from the different structures of the allylic indiums. To our delight, diene 1c made it possible to establish contiguous quaternary C–C bonds with ketones 2a–2c (eqn (2)). To date, construction of contiguous quaternary C–C bonds with a catalyst remains a challenging task in organic synthesis,18 and the task has never been realized by the same type of reductive coupling that is catalyzed by transition metal catalysts.Open in a separate windowScheme 2Application of substituted 1,3-butadienes to the coupling.Our proposal of the reaction mechanism is described in Scheme 3. Initially, prepared InCl2(OMe) is reduced by MePhSiH2 to give HInCl2. The indium radical is formed in the presence of tiny amounts of O2 and adds to diene 1a.17 The stable allylic radical A extracts hydrogen from InCl2H to afford allylic indium B, which regenerates the indium radical. Following the allylation of ketone 2, the generated indium alkoxide 3′ is protonated by CH3OH to give the product 3 and InCl2(OMe). The reaction mechanism was investigated using a deuterated silane, Ph2SiD2 (Scheme 4). We found that the product 3aa-CH2D was afforded without any other deuterated compound. The product 3aa-CH2D is formed from δ-deuterated intermediate B-d1 as shown in Scheme 4. Further investigation on the reaction mechanism is ongoing in our laboratory.Open in a separate windowScheme 3A plausible catalytic cycle.Open in a separate windowScheme 4Deuterated experiments of allylation of ketone 2a.Finally, vinyl cyclopropane 4, a diene derivative, was tested for reductive coupling with ketones.19 The desired product 5a was produced in the presence of a radical initiator, V-70L, even though diastereoselectivity was not achieved (Scheme 5, eqn (1)). This could have been caused by low E/Z selectivity of the allylic indiums. The seminal work developed by Buchwald that was related to a Cu–H catalyzed reaction did not allow the use of vinyl cyclopropane as a reactant because their method has no process for a radical opening of the cyclopropane ring (Scheme 5, eqn (2)).9 Our method expands the scope of the dienes by allowing use of their derivatives.Open in a separate windowScheme 5Coupling of vinyl cyclopropanes with ketones.In summary, we developed a process whereby the reductive coupling of 1,3-dienes with various ketones could be sufficiently catalyzed by HInCl2. This approach allowed the introduction of functional groups into homoallylic alcohols, which generated sequential Ctert–Ctert bonds with expansion to vinyl cyclopropane 4. Application to an asymmetric version of the coupling and improvement of the diastereoselectivity are underway.  相似文献   
68.
A role for gamma-aminobutyric acid (GABA)ergic inhibition in cortical sensory processing is one of the principle concerns of brain research. Angelman syndrome (AS) is thought to be one of the few neurodevelopmental disorders with GABAergic-related genetic involvement. AS results from a functional deficit of the imprinted UBE3A gene, located at 15q11-q13, resulting mainly from a 4-Mb deletion that includes GABA(A) receptor subunit genes. These genes are believed to affect the GABAergic system and modulate the clinical severity of AS. To understand the underlying cortical dysfunction, we have investigated the primary somatosensory-evoked responses in AS patients. Subjects included eleven AS patients with a 15q11-q13 deletion (AS Del), two AS patients without a 15q11-q13 deletion, but with a UBE3A mutation (AS non-Del), six epilepsy patients (non-AS) and eleven normal control subjects. Somatosensory-evoked fields (SEFs) in response to median nerve stimulation were measured by magnetoencephalography. The N1m peak latency in AS Del patients was significantly longer (34.6+/-4.8 ms) than in non-AS patients (19.5+/-1.2 ms, P<0.001) or normal control subjects (18.4+/-1.8 ms, P<0.001). The next component, P1m, was prolonged and ambiguous and was only detected in patients taking clonazepam. In contrast, SEF waveforms of AS non-Del patients were similar to those of control individuals, rather than to AS Del patients. Thus, GABAergic dysfunction in AS Del patients is likely due to hemizygosity of GABA(A) receptor subunit genes, suggesting that GABAergic inhibition plays an important role in synchronous activity of human sensory systems.  相似文献   
69.
The aim of our study was to evaluate whether corrected QT dispersion (QTc dispersion), an electrocardiographic marker, is a good predictor of the development of acute heart failure after high-dose chemotherapy followed by autologous or allogeneic hematopoietic stem cell transplantation. We enrolled 50 consecutive patients, from age 15 to 63 years, with hematopoietic diseases scheduled to undergo autologous or allogeneic hematopoietic stem cell transplantation, and compared QTc dispersion with other markers before transplantation conditioning. In univariate logistic analysis, QTc dispersion was a significant factor for acute heart failure after hematopoietic stem cell transplantation (odds ratio, 3.7 per 10 msec; confidence interval, 1.6-8.5; P = 0.002). There were no significant differences as age, sex, systolic or diastolic echocardiographic function markers, cumulative anthracycline dose, or QTc before transplantation between patients with and without acute heart failure. After multiple adjustments for left ventricular ejection fraction, cumulative anthracycline dose, cyclophosphamide conditioning dose, QTc dispersion was a significant and independent factor for acute heart failure after hematopoietic stem cell transplantation (odds ratio, 48.0 per 10 msec; confidence interval, 1.4-1666.3; P = 0.03). This study demonstrated that QTc dispersion could be used as a powerful noninvasive predictor of the development of acute heart failure after hematopoietic stem cell transplantation.  相似文献   
70.
    
The optimal pre-transplant conditioning for aplastic anemia (AA) remains unclear. We performed a prospective study on allogeneic transplantation from a related or unrelated donor for adult patients with AA. We assessed whether reduced-dose cyclophosphamide (CY) could decrease toxicity while maintaining engraftment, and low-dose thymoglobulin could safely prevent graft-vs-host disease (GVHD). The pre-transplant conditioning regimen consisted of fludarabine 120 mg/m2, CY 100 mg/kg, and thymoglobulin 2.5 mg/kg with or without 2 Gy of total body irradiation. Twenty-seven patients with a median age of 36 years were analyzed. Sixteen patients received graft from related donors. The stem cell source was bone marrow in 26 patients. All of the patients but one, who died early, achieved neutrophil engraftment at a median of 19 days. Mixed chimerism was observed in six and five patients at days 30 and 90, respectively. Only one patient experienced secondary engraftment failure with complete donor-type chimerism. None of the patients developed severe acute GVHD. The cumulative incidence of chronic GVHD was 37.7% at 1 year. The overall survival rate was 96.3% at 1 year and 3 years. A high EB virus-DNA load was detected in one patient at days 60. No one developed EBV-lymphoproliferative disorder within a year. The results suggest that the conditioning regimen in this study was safe and effective. However, relatively high incidence of chronic GVHD needs further improvement.  相似文献   
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