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91.
Michio Maeta Hiroaki Saito Akira Kondo Hiroshi Yamashiro Syunichi Tsujitani Masahide Ikeguchi Nobuaki Kaibara 《Gastric cancer》1998,1(1):57-63
Background.
In Japan, much attention has recently been paid to super-extended paraaortic lymphadenectomy (PAL) for the treatment of advanced
gastric cancer. However, it has been reported that PAL is associated with increased morbidity and mortality, as compared to
conventional extended lymphadenectomy (D2 or D3). Therefore, an analysis of the effects of PAL on perioperative changes in
the biological responses of patients essential for determining the potential utility of this procedure.
Methods.
The current non-randomized prospective study included evaluations of perioperative changes in parameters of surgical stress
(series I; serum levels of antidiuretic hormone, interleukin-6, trypsin, and phospholipase A
2
) and immunocompetence (series II; phytohemagglutinin- and concanavalin A-induced blastogenesis, activity of natural killer
cells and the ratio of CD4 cells to CD8 cells) in patients with advanced gastric cancer (T3 or T4), comparing groups treated
with D3 plus PAL (
n
= 12) and D3 (
n
= 13), and a control group with early gastric cancer (
n
= 16) treated with D1 lymphadenectomy (perigastric N1 nodes) between April 1995 and April 1997.
Results.
The duration of surgery and the amount of blood lost were longer and greater in the D3 plus PAL group than in the D3 and D1
groups. D3 plus PAL and D3 were associated with significant postoperative increases in parameters of surgical stress, as well
as with significant postoperative immunosuppression, compared to results with D1. However, there were no significant differences
in the respective parameters between the D3 plus PAL and D3 groups.
Conclusions.
Our results indicate that there are no essential differences in patients' biological responses between D3 plus PAL and D3
lymphadenectomy. It appears that PAL-associated morbidity can be minimized by very careful manipulation during the dissection
of paraaortic lymph nodes.
Received for publication on Feb. 10, 1998; accepted on Jun. 3, 1998 相似文献
92.
Yumi Kojima Yoichi Aoki Hiroaki Kase Shoji Kodama Kenichi Tanaka 《International journal of clinical oncology / Japan Society of Clinical Oncology》1998,3(3):143-146
Background The purpose of this study was to assess the accuracy of contrast-enhanced magnetic resonance imaging (dynamic MR imaging)
in the evaluation of preinvasive and early invasive cancer of the cervix.
Methods Twenty-nine women with untreated squamous cell carcinoma of the cervix with either no stromal invasion or early stromal invasion
underwent pretreatment MR imaging and dynamic MR imaging within 4 weeks of surgical evaluation. The images were evaluated
for tumor detection and compared with results of histologic examination of the surgical specimens.
Results The lesions in 17 cases with histologically proven stromal invasion of 4 mm or greater were detected with dynamic MR imaging,
whereas lesions in only 8 of these cases were detected with T2 imaging. In 9 cases with stromal invasion between 4.0 mm and
5.0 mm, lesions were represented as early phase focal enhancement on dynamic MR images, but not detected on T2-weighted images.
In the 12 cases with less than 4 mm stromal invasion, no lesions were visualized on either T2-weighted images or dynamic MR
images, except in 1 case of glandular involvement without stromal invasion that appeared as enhancement on early-phase dynamic
MR imaging.
Conclusion Dynamic MR imaging detected more lesions of early stromal invasion in pretreatment imaging for cervical cancer than nonenhanced
MR imaging. 相似文献
93.
Hiroaki Okamoto Akira Nagatomo Hideo Kunitoh Hiroshi Kunikane Koshiro Watanabe 《Cancer chemotherapy and pharmacology》1998,42(4):307-312
Purpose: Carboplatin doses can be individualized using the formula of Calvert et al. (Calvert formula) dose (mg) = area under the
plasma concentration versus time curve (AUC) · [glomerular filtration rate (GFR) + 25]. Creatinine clearance (Ccr), either
measured by the 24-h method or calculated by the formula of Cockcroft and Gault [Cockcroft-Gault (CG) formula], is often substituted
for the GFR. The CG formula is based on patient weight, age and sex, and the serum creatinine (Cr) concentration. Another
method for predicting carboplatin clearance (CL) using patient characteristics has also been proposed by Chatelut et al. (Chatelut
formula). This study was undertaken to evaluate the performance of the three formulae in predicting standard- and low-dose
carboplatin pharmacokinetics. Methods: A total of 52 patients with advanced lung cancer were enrolled in this pharmacokinetic study; 37 received standard-dose
carboplatin and 25 received low-dose carboplatin. The Cr concentration was measured using an enzymatic assay. The three formulae
were used to predict carboplatin CL. The median absolute percent error (MAPE) for each formula was evaluated by comparing
the calculated and observed CL. For comparison of AUCs, free platinum plasma concentrations were measured at intervals up
to 24 h after carboplatin administration. AUCs were determined and compared with predicted values. Results: In the standard-dose carboplatin group, the MAPEs for the prediction of carboplatin CL from the 24-h Calvert, CG-Calvert
and Chatelut formulae were 13%, 12% and 23%, respectively. In the low-dose carboplatin group, the corresponding MAPEs were
27%, 18% and 44%, respectively. Observed standard-dose carboplatin AUCs after aiming for target AUCs of 5 and 6 mg · min/ml
using the Calvert formula based upon the 24-h Ccr were 5.3 ± 0.8 and 5.9 ± 0.8, respectively, indicating a small and acceptable
bias compared with that predicted from the dosing formula. Conclusions: The pharmacokinetics of standard-dose carboplatin were accurately predicted by the Calvert formula based upon either 24-h
or CG-calculated Ccr, but not by the Chatelut formula. Either CG-calculated or 24-h Ccr can be substituted for the GFR in
the Calvert formula for the determination of individual doses. The poor predictability of the Chatelut formula found in this
study might be the result of a differences in either the Cr assay or the patient population. Therefore, formulae which attempt
to estimate GFR are not necessarily valid if either the Cr assay or the patient population is changed.
Received: 23 July 1997 / Accepted: 16 December 1997 相似文献
94.
Association of Loss of Heterozygosity at the p53 Locus with Chemoresistance in Osteosarcomas 总被引:4,自引:0,他引:4
Akiteru Goto Hiroaki Kanda Yuichi Ishikawa Seiichi Matsumoto Noriyoshi Kawaguchi Rikuo Machinami Yo Kato Tomoyuki Kitagawa 《Cancer science》1998,89(5):539-547
Although the osteosarcoma is considered to be among the most chemosensitive malignancies and preoperative chemotherapy is commonly applied, an appreciable proportion of cases are in fact quite insensitive. Predictive markers for chemosensitivity are therefore desirable in order to develop effective treatment strategies. Thirty-two cases of conventional osteosarcomas treated at the Cancer Institute Hospital, Tokyo, were analyzed. The sensitivity to preoperative chemotherapy was investigated with reference to loss of heterozygosity (LOH) at the 17p13 ( p 53) and 13q14 ( Rb ) loci and expression of the cell-cycle associated proteins, p53, Rb, p21/Waf-1, mdm-2 and Ki-67, as detected immunohistochemically. LOH was detected by analyzing polymerase chain reaction products at marker microsatellite loci. The efficacy of chemotherapy was evaluated both radiologically and histologically. LOH at p 53 or Rb loci was seen in 54% (13/24) and 58% (14/24) of cases, respectively. Only 15% of osteosarcomas with LOH at the p 53 locus were sensitive to preoperative chemotherapy, as compared to 64% of tumors without such loss ( P <0.05). A similar but much less distinct tendency was observed with LOH at the Rb locus. No relationship was evident between chemosensitivity and immunohistochemical staining patterns for p53, Rb, p21/Waf-1, mdm-2 or Ki-67. The results suggest that p 53 gene deletion, but not the other parameters investigated, may be useful for predicting chemoresistance of osteosarcomas. 相似文献
95.
Daisuke Abe Toshiyuki Sakaki Tatsuya Kusudo Atsushi Kittaka Nozomi Saito Yoshitomo Suhara Toshie Fujishima Hiroaki Takayama Hiromi Hamamoto Masaki Kamakura Miho Ohta Kuniyo Inouye 《Drug metabolism and disposition》2005,33(6):778-784
Recently, we demonstrated that some A-ring-modified vitamin D3 analogs had unique biological activity. Of these analogs, 2alpha-propoxy-1alpha,25(OH)2D3 (C3O1) and 2alpha-(3-hydroxypropoxy)-1alpha,25(OH)2D3 (O2C3) were examined for metabolism by CYP27A1 and CYP24A1. Surprisingly, CYP27A1 catalyzed the conversion from C3O1 to O2C3, which has 3 times more affinity for vitamin D receptor than C3O1. Thus, the conversion from C3O1 to O2C3 by CYP27A1 is considered to be a metabolic activation process. Five metabolites were detected in the metabolism of C3O1 and O2C3 by human CYP24A1 including both C-23 and C-24 oxidation pathways. On the other hand, three metabolites of the C-24 oxidation pathway were detected in their metabolism by rat CYP24A1, indicating a species-based difference in the CYP24A1-dependent metabolism of C3O1 and O2C3 between humans and rats. Kinetic analysis revealed that the Km and kcat values of human CYP24A1 for O2C3 are, respectively, approximately 16 times more and 3 times less than those for 1alpha,25(OH)2D3. Thus, the catalytic efficiency, kcat/Km, of human CYP24A1 for O2C3 is only 2% of 1alpha,25(OH)2D3. These results and a high calcium effect of C3O1 and O2C3 in animal experiments using rats suggest that C3O1 and O2C3 are promising for clinical treatment of osteoporosis. 相似文献
96.
Masakatsu Fujinoki Tatsuya Suzuki Takeshi Takayama Hiroaki Shibahara Hideki Ohtake 《Reproductive Medicine and Biology》2006,5(2):123-135
Background and Aims It has been widely accepted that sperm hyperactivation is regulated by protein phosphorylations. But, the sperm hyperactivation
phosphorylation pathway is not well understood yet because several different proteins have been detected in other studies.
In order to understand the phosphorylation pathway that regulates hyperactivation, we established how to extract sperm protein
completely and detected proteins that were phosphorylated during hyperactivation.
Methods Protein phosphorylation of hamster spermatozoa was detected by western blotting using antiphospho-amino acid monoclonal antibodies
or the SELDI ProteinChip system with IMAC-Ga(III).
Results We detected 75 protein/peptide phosphoryations using the method established in the present study. Tyrosine phosphorylations
occurred during hyperactivation. Serine or threonine phosphorylations occurred for 30 min. Furthermore, four of the serine
or threonine phosphorations were phosphorylated by A-kinase. As for peptides, 15 peptides were dephosphorylated for 30 min.
Other peptides were phosphorylated during hyperactivation.
Conclusions Because most of the proteins detected in the present study have been described previously, we could detect comprehensive protein
phosphorylations. Moreover, we also detected many novel phosphopeptides. Although we did not understand the role of peptide,
it was likely that motility was basically regulated by serine/threonine phosphorylations and hyperactivation was mainly regulated
by tyrosine phosphorylations. (Reprod Med Biol 2006; 5: 123–135) 相似文献
97.
98.
99.
Marquis P Vawter Simon Evans Prabhakara Choudary Hiroaki Tomita Jim Meador-Woodruff Margherita Molnar Jun Li Juan F Lopez Rick Myers David Cox Stanley J Watson Huda Akil Edward G Jones William E Bunney 《Neuropsychopharmacology》2004,29(2):373-384
Gender differences in brain development and in the prevalence of neuropsychiatric disorders such as depression have been reported. Gender differences in human brain might be related to patterns of gene expression. Microarray technology is one useful method for investigation of gene expression in brain. We investigated gene expression, cell types, and regional expression patterns of differentially expressed sex chromosome genes in brain. We profiled gene expression in male and female dorsolateral prefrontal cortex, anterior cingulate cortex, and cerebellum using the Affymetrix oligonucleotide microarray platform. Differentially expressed genes between males and females on the Y chromosome (DBY, SMCY, UTY, RPS4Y, and USP9Y) and X chromosome (XIST) were confirmed using real-time PCR measurements. In situ hybridization confirmed the differential expression of gender-specific genes and neuronal expression of XIST, RPS4Y, SMCY, and UTY in three brain regions examined. The XIST gene, which silences gene expression on regions of the X chromosome, is expressed in a subset of neurons. Since a subset of neurons express gender-specific genes, neural subpopulations may exhibit a subtle sexual dimorphism at the level of differences in gene regulation and function. The distinctive pattern of neuronal expression of XIST, RPS4Y, SMCY, and UTY and other sex chromosome genes in neuronal subpopulations may possibly contribute to gender differences in prevalence noted for some neuropsychiatric disorders. Studies of the protein expression of these sex-chromosome-linked genes in brain tissue are required to address the functional consequences of the observed gene expression differences. 相似文献
100.
Noriaki Sako Nobuhiro Kaku Yoshiki Kitahara Yuta Kubota Hiroaki Tagomori Hiroshi Tsumura 《Clinics in Orthopedic Surgery》2022,14(2):196
BackgroundPatients with developmental dysplasia of the hip (DDH) are known to have abnormal pelvic morphologies; however, rotation of innominate bone features remains unclear. Thus, we investigated innominate bone rotation in patients with DDH by measuring the associated angles and distances using three-dimensional (3D) computed tomography.MethodsWe defined four straight lines in pelvic 3D models: from the anterior superior iliac spine to the posterior superior iliac spine, from the anterior inferior iliac spine to the posterior inferior iliac spine, from the pubic tubercle to the ischial spine, and from the pubic tubercle to the ischial tuberosity. Similarly, we measured the angles formed by these lines using the vertical axis of the anterior pelvic plane on the horizontal plane and the horizontal axis on the sagittal plane. Additionally, we measured the distances between the femoral head centers and the acetabular centers in the coronal plane.ResultsThe difference in internal rotation angle between the superior and inferior parts of the iliac bone was significantly lower, by approximately 1.7°, in the DDH group than in the control group (p = 0.007); the difference between the inferior and superior parts of the ischiopubic bone was significantly higher, by approximately 1.5°, in the DDH group (p < 0.001). In the sagittal plane, the sum of the superior aspect of the iliac bone and the inferior aspect of the ischium was significantly lower in the DDH group (p = 0.001) than in the control group. The distances between the femoral heads and the acetabula were significantly greater in the DDH group than in the control group (p = 0.03, p < 0.01, respectively).ConclusionsPatients with DDH had a more internally rotated ilium and ischiopubic bone than normal individuals; however, it should be emphasized that internal rotation was reduced near the acetabulum, and the acetabulum was shifted laterally. Similarly, it was shown that patients with DDH had different rotations of the ilium and ischiopubic bone in the sagittal plane. 相似文献