Biomedical subjects

M Mukai

Publications and source records attributed to M Mukai.

At least 145 records · Page 8Linked to original sources

PubMed1997

Surgical management of gastric leiomyosarcoma: evaluation of the propriety of laparoscopic wedge resection.

Laparoscopic surgery has been applied to malignant gastric tumors. To evaluate the propriety of laparoscopic wedge resection for gastric leiomyosarcoma it is necessary to question whether lymph node dissection is necessary for the surgical management of gastric leiomyosarcoma. A retrospective study on open surgery cases of gastric leiomyosarcoma was performed to address this issue. The clinical records of 28 patients with gastric leiomyosarcoma who had had surgery were examined. The patients who underwent open surgery were divided into a systematic lymph node dissection (SLND) group (n = 9) and a nondissection (non-D) group (n = 19). No patient had lymph node metastasis at the time of operation or recurrence, and statistical analysis showed no difference between the SLND and non-D groups in terms of survival rates. These data suggest that SLND might not be necessary for the surgical management of gastric leiomyosarcoma and that laparoscopic wedge resection of the stomach can be considered a first-line treatment for gastric leiomyosarcoma.

Adult↗

PubMed1997

A hybrid carcinoma: adenoid cystic carcinoma and salivary duct carcinoma of the salivary gland. An immunohistochemical study.

Hybrid tumours of the salivary glands are very rare entities composed of two different tumours, each of which conforms with an exactly defined category. We describe an unusual hybrid carcinoma of the palate; it was comprised of an adenoid cystic carcinoma and a salivary duct carcinoma with a transitional region. These two different compartments showed different characteristics as regards cellular differentiation, proliferative activity, and expression of oncogene and tumour suppressor oncogene proteins, as revealed by using markers for muscle actin, keratin, vimentin, S-100 protein, GFAP, Ki-67, p53, and c-erbB-2 proteins. This case is the first reported with overexpression of p53 and c-erbB-2 proteins in the tumour entities. Salivary gland tumours consist of heterogeneous histological groups, and each has morphological diversity. This case indicates that some of the oncogene and tumour suppressor oncogene proteins may help to produce the histological heterogeneity of the salivary gland tumour.

Actins↗

PubMed1997

Helicobacter pylori infection and gastric cancer. A nested case-control study in a rural area of Japan.

We conducted a seroepidemiological nested case-control study to determine the association of gastric cancer with Helicobacter pylori infection and atrophic gastritis. A cohort of 2858 participants in an annual multiphasic health check-up were followed for eight years. Data for 45 gastric cancer cases and 225 sex-, age-, and address-matched control subjects were analyzed. Helicobacter pylori infection was determined by IgG antibodies, and atrophic gastritis was diagnosed by both serum pepsinogen I level (< or = 70 ng/ml) and the pepsinogen I/II ratio (< or = 3.0). Univariate analysis showed that Helicobacter pylori and atrophic gastritis were significantly associated with gastric cancer. In a multivariate analysis, atrophic gastritis was associated with significantly increased risk of cancer (odds ratio, 3.38; 95% confidence interval, 1.54-7.42); however, Helicobacter pylori was not associated with cancer (odds ratio, 1.84; 95% confidence interval, 0.59-5.72). These results suggest that Helicobacter pylori infection alone is not directly associated with gastric carcinogenesis but has an indirect relation to gastric cancer through the development of atrophic gastritis.

Adult↗

PubMed1997

Helicobacter pylori infection and atrophic gastritis. A case-control study in a rural town of Japan.

We enrolled five hundred twenty-one patients with atrophic gastritis and 769 controls in a case-control study of atrophic gastritis and Helicobacter pylori infection and lifestyle factors. The participants had no history of upper gastrointestinal surgery. They were selected from 1,395 adult (35 years or older) residents of a rural town in Kyoto prefecture who participated in an annual health examination in 1987. Atrophic gastritis was diagnosed on the basis of serum pepsinogen levels: pepsinogen I levels (< or = 70 ng/ml) and pepsinogen I/pepsinogen II ratios (< or = 3.0). The presence of immunoglobulin G antibodies to H. pylori indicated H. pylori infection. At the time of the health examination, participants were interviewed about daily lifestyle habits such as use of cigarettes and alcoholic beverages and consumption of green-yellow vegetables. Unconditional logistic regression analysis indicated that H. pylori infection was associated with a significantly increased risk for atrophic gastritis for all participants (odds ratio, 8.17; 95% confidence interval, 5.63-11.84); for men (odds ratio, 10.91; 95% CI, 5.25-22.67); and for women (odds ratio, 7.28; 95% CI, 4.72-11.22). We found no statistically significant relations between lifestyle factors and atrophic gastritis.

Adult↗

PubMed1997

NG-nitro-L-arginine methyl ester inhibits bone metastasis after modified intracardiac injection of human breast cancer cells in a nude mouse model.

We investigated the effects of NG-nitro-L-arginine-methyl ester (L-NAME), a nitric oxide synthase (NOS) inhibitor, on bone metastasis of human breast cancer, MDA-231 cells. Tumor cells (2 x 10(5) cells in 0.2 ml of phosphate-buffered saline; PBS) were injected through the diaphragm into the left ventricle of the heart of laparotomized nude mice (male 5-week-old ICR-nu/nu). L-NAME (2 mg/mouse/injection in 0.1 ml of PBS) was given intraperitoneally to mice 6 h and 3 h before and immediately, 3 h, 6 h, 18 h and 21 h after the intracardiac injection of tumor cells. As a control, 0.1 ml of PBS was injected instead of L-NAME. The effect of NG-nitro-D-arginine-methyl ester (D-NAME; 2 mg/mouse/injection), an inactive analogue of L-NAME, was also investigated to evaluate the specificity of L-NAME action. Radiographical examination 31 days after the tumor-cell injection showed that the incidence and number of osteolytic bone metastases and the number of bones with metastasis in L-NAME-treated mice were significantly reduced compared with those in PBS-treated mice (P < 0.05). The differences between PBS-treated and D-NAME-treated mice were not significant. Our findings suggest that specific and appropriate NOS inhibitors may represent a new pharmacological approach to therapy for cancer patients at risk of developing osteolytic bone metastases.

Animals↗

PubMed1997

Neurons and extracellular neurofibrillary tangles in the hippocampal subdivisions in early-onset familial Alzheimer's disease: a case study.

We have investigated morphometrically unaffected neurons, intracellular neurofibrillary tangles (I-NFT) and extracellular neurofibrillary tangles (E-NFT) in eight subdivisions of the hippocampal cortex in two cases of early-onset familial Alzheimer's disease (FAD) and six cases of early-onset sporadic Alzheimer's disease (SAD). The hippocampal subdivisions examined included: CA4, CA3, CA2, CA1, prosubiculum, subiculum and presubiculum (PRE), parasubiculum (PARA) and entorhinal cortex (ENT). CA3, CA2 and CA1 in the FAD cases showed more severe neuronal loss and much greater E-NFT formation than in the SAD cases, while ENT in both the FAD cases showed less neuronal loss and less E-NFT formation. These data suggest that the cornu ammonis is affected more severely than the ENT in the FAD cases. These observations indicate that hippocampal pathology in the FAD cases is qualitatively as well as quantitatively different from that in sporadic cases. These results provide further evidence for pathological heterogeneity in AD, although the number of FAD cases examined is very small.

Aged↗

PubMed1997

Malignant fibrous histiocytoma of the cecum: report of a case and review of the literature.

Malignant fibrous histiocytoma (MFH) of the gastrointestinal tract is extremely rare. Here we report a case of MFH of the cecum and review other cases of large bowel MFH in the literature. A 64-year-old man had a large tumor mass in the cecum associated with multiple small peritoneal implants. Histologically, most of the lesion showed inflammatory pseudotumor-like appearance; that is, a mixed proliferation of fibroblasts and myofibroblasts loosely arranged in sweeping fascicles or whorled structures and an admixture of chronic inflammatory cell infiltrate. The myofibroblastic nature of the spindle-shaped cells was confirmed by their immunohistochemical and ultrastructural findings. In addition, there was atypical histiocytic cells infiltrate in some areas and marked lymphatic involvement and lymph node metastasis by such histiocytic cells. These features were interpreted as MFH, although it had to be distinguished from inflammatory fibrosarcoma and leiomyosarcoma. The differential diagnosis is discussed here.

Actins↗

PubMed1997

Detection of human papillomavirus infection in squamous tumours of the conjunctiva and lacrimal sac by immunohistochemistry, in situ hybridisation, and polymerase chain reaction.

BACKGROUND: Squamous tumours of the ocular surface, including the lacrimal pathway, range from benign lesions to invasive carcinomas. Some of these tumours are associated with human papillomavirus (HPV) infection, with the types of HPV differing among papillomas and dysplastic or malignant lesions. METHODS: The relation between squamous tumours of the conjunctiva and lacrimal sac and HPV infection was investigated in 17 individuals with such tumours. Nine of the 17 tumours were benign, four were dysplastic lesions, and four were carcinomas. RESULTS: Eight specimens showed positive immunohistochemical staining with antibodies to HPV; four of these eight were papillomas, three were dysplastic lesions, and one was a carcinoma. Koilocytosis was detected in seven of these eight tumours. Five of the eight specimens positive for immunohistochemical staining were also positive for HPV DNA by in situ hybridisation, and all eight were positive for HPV DNA by the polymerase chain reaction (PCR) method. CONCLUSION: Approximately 50% of squamous tumours of the ocular surface and lacrimal sac were associated with HPV infection. This is the first report, to our knowledge, of the detection of HPV in the field of ophthalmology by a combination of immunohistochemistry, in situ hybridisation, and PCR.

Adult↗

PubMed1997

Angiomyolipoma: imaging findings in lesions with minimal fat.

PURPOSE: To investigate a method of diagnosing angiomyolipoma that contains minimal fat. MATERIALS AND METHODS: In six cases of angiomyolipoma with minimal fat, the attenuation on contrast material-enhanced and unenhanced computed tomographic (CT) images, the echogenicity on sonograms, the signal intensity on T2-weighted magnetic resonance (MR) images, and the gross configuration of the lesion were retrospectively analyzed. In 100 cases of renal cell carcinoma, the same parameters were analyzed, and results were compared with those of angiomyolipoma. RESULTS: When compared with the surrounding renal parenchyma, all six angiomyolipomas showed homogeneously high attenuation on unenhanced CT images, homogeneous enhancement on contrast-enhanced CT images, and homogeneous isoechogenicity on sonograms. Of the five angiomyolipomas examined with MR imaging, four were hypointense and one was isointense on T2-weighted images. All six angiomyolipomas protruded from the renal margin. None of the 100 renal cell carcinomas showed homogeneously high attenuation on unenhanced CT images, homogeneous enhancement on contrast-enhanced CT images, or homogeneous isoechogenicity on sonograms. CONCLUSION: In the kidney, homogeneously high attenuation on unenhanced CT images, homogeneous enhancement on contrast-enhanced CT images, and homogeneous isoechogenicity on sonograms are suggestive of angiomyolipoma that contains abundant muscle and minimal fat.

Adipose Tissue↗

PubMed1997

Recognition of beta-lactam antibiotics by rat peptide transporters, PEPT1 and PEPT2, in LLC-PK1 cells.

PEPT1 and PEPT2 are H(+)-coupled peptide transporters expressed preferentially in the intestine and kidney, respectively, which mediate uphill transport of oligopeptides and peptide-like drugs such as beta-lactam antibiotics. In the present study, we have compared the recognition of beta-lactam antibiotics by LLC-PK1 cells stably transfected with PEPT1 or PEPT2 cDNA. Cyclacillin (aminopenicillin) and ceftibuten (anionic cephalosporin without an alpha-amino group) showed potent inhibitory effects on the glycylsarcosine uptake in the PEPT1-expressing cells. Other beta-lactams, such as cephalexin, cefadroxil, and cephradine (aminocephalosporins), inhibited modestly the PEPT1-mediated glycylsarcosine uptake. Except for ceftibuten, these beta-lactams showed much more potent inhibitions on the glycylsarcosine uptake via PEPT2 than via PEPT1. Comparison of the inhibition constant (Ki) values between cefadroxil and cephalexin suggested that the hydroxyl group at the NH2-terminal phenyl ring increased affinity for both PEPT1 and PEPT2. It is concluded that PEPT2 has a much higher affinity for beta-lactam antibiotics having an alpha-amino group than PEPT1 and that substituents at the NH2-terminal side chain of these drugs are involved in the recognition by both peptide transporters.

Animals↗

PubMed1997

Plasma adrenomedullin concentrations and cardiac and arterial hypertrophy in hypertension.

It has been reported that plasma concentrations of adrenomedullin (AM), a novel vasodilator peptide, are higher in patients with essential hypertension than those in normotensive subjects. To clarify the clinical significance of increased levels of AM in patients with essential hypertension, in this study we examined the relationship between plasma concentrations of AM and the structure of the left ventricle or carotid artery. Plasma AM concentrations; renin activity; and norepinephrine, epinephrine, and creatinine concentrations in 50 patients with untreated essential hypertension without renal dysfunction and heart failure were measured. We also measured the mean wall thickness of the left ventricle and left ventricular mass index by M-mode echocardiography and intimal-medial thickness and arterial distensibility of the carotid artery by ultrasonography. Hypertensive patients were divided into two groups: hypertensives with and those without left ventricular hypertrophy. Plasma AM concentrations in hypertensive patients with left ventricular hypertrophy were significantly higher than in hypertensive patients without left ventricular hypertrophy (7.87+/-2.70 vs 5.74+/-1.65 fmol/mL, P<.01). In all hypertensive patients, plasma AM concentrations were not correlated with blood pressure, plasma renin activity, plasma norepinephrine, plasma epinephrine, or plasma creatinine concentration. Plasma AM concentrations were positively correlated with left ventricular mass index or mean wall thickness (r=.37, P=.009; r=.40, P=.004, respectively) and inversely correlated with carotid artery distensibility (r=-.33, P=.02), whereas plasma AM concentrations were not correlated with intimal-medial thickness. These results suggest that the observed elevation of plasma AM in patients with essential hypertension with normal renal function may be partly related to cardiac hypertrophy and decreased carotid artery distensibility.

Adrenomedullin↗

PubMed1997

Lupus erythematosus profundus around the salivary glands: a case resembling submandibular salivary gland disease.

In a 29 year old Japanese woman with SLE, a bilateral submandibular mass was detected. Computed tomographic (CT) scan suggested inflammatory changes around the submandibular glands. Histological findings of the deep skin biopsy showed typical changes of lupus erythematosus profundus (LEP). LEP should be considered in the differential diagnosis of an unexplained submandibular mass in a subject with SLE.

Adult↗

PubMed1997

Effects of ACE inhibitors versus calcium antagonists on left ventricular morphology and function in patients with essential hypertension.

We compared the effects of two long-term antihypertensive treatments (ACE inhibitors vs. Ca antagonists) on left ventricular hypertrophy (LVH) and LV function in patients with essential hypertension and LVH. After a washout period of at least 4 wk, ceronapril or delapril was administered to 18 patients and nifedipine or nicardipine to 15 patients for 6 months. Mean blood pressure (MBP), LV mass (LVM), LV fractional shortening (FS), systolic time intervals (ejection time/pre-ejection period ratio = ET/PEP), and isovolumic relaxation time (IRT) were examined in the pretreatment phase and after 6 months of treatment. MBP and LVM significantly and similarly decreased after treatment in both groups (ACE inhibitors vs. Ca antagonists, delta MBP: -17.1 +/- 1.3 vs. -16.9 +/- 1.6%; delta LVM: -11.7 +/- 2.7 vs. -10.0 +/- 3.8%, both p = not significant). ACE inhibitors produced significant beneficial changes in FS, ET/PEP, and IRT after treatment as compared with Ca antagonists (ACE inhibitors vs. Ca antagonists, delta FS: 11.8 +/- 3.3 vs. 5.1 +/- 4.1%, p < 0.05; delta ET/PEP: 11.9 +/- 2.3 vs. 4.7 +/- 6.4%, p < 0.05; delta IRT: -12.0 +/- 3.4 vs. -3.8 +/- 6.1%, p < 0.05). The results indicate that both ACE inhibitors and Ca antagonists induce significant and similar reductions in blood pressure and LVM in hypertensive patients. ACE inhibitors produce significant improvements in LV function in both systolic and diastolic phases as compared with Ca antagonists.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed1997

Specific inhibition of PCR by non-extendable oligonucleotides using a 5' to 3' exonuclease-deficient DNA polymerase.

The Stoffel fragment of Taq DNA polymerase lacks the 5' to 3' exonuclease activity that hydrolyzes potentially blocking DNA strands during primer extension. We there-fore asked whether by using this fragment in the PCR, non-extendable, base-paired oligonucleotides could inhibit amplification in a sequence-dependent manner. Model targets were chosen from the partially conserved ribosomal 16S rDNA of three bacterial species: E. coli, Bacillus subtilis and Neisseria gonorrhoea. A single pair of primers was capable of amplifying a homologous 240-bp region from all three. Two non-extendable "blocking" oligonucleotides were synthesized with sequences complementary to the inter-primer regions of E. coli and B. subtilis, respectively. Both blockers were shown specifically to prevent amplification of their complementary targets, but not of the reciprocal control targets or of the reciprocal control targets or of the non-complementary N. gonorrhea. Specificity was further confirmed by an internal positive control. Similar inhibition was seen with mixtures of targets in a single reaction. With intact Taq DNA polymerase, no blocking was observed. Primers and blockers targeting specific regions of N. gonorrhoea rDNA were used to confirm the requirement that blockers be directed to the inter-primer region. Sequence-dependent amplification inhibition, such as that demonstrated here, would be applicable to PCR-related strategies using primers capable of using multiple targets, where such selective inhibition could be useful.

Bacillus subtilis↗

PubMed1997

[The use of high resolution MR imaging for pre-treatment evaluation of breast cancer: detection of intraductal spread].

Thirty-two patients were examined in order to evaluate the role of high-resolution MRI in the treatment planning of breast cancer. A 1.5T Signa imager (GE Medical Systems) was used with dedicated receive-only breast coil. The pulse sequence based on RARE was used with the fat-suppression technique. After examining both breasts with larger FOV (30 cm), the affected breast alone was examined with smaller FOV (18 cm) and larger matrix (512 x 384) with Gd enhancement. Breast cancer showed more prominent and earlier enhancement compared with normal breast tissue. Linear or spotty continuous enhancement from the main tumor was considered to be suggestive of intraductal spread. Of 32 patients, 20 showed linear or spotty enhancement around the main tumor on MRI, and 15 of these 20 had intraductal spread. On the other hand, 12 out of 32 patients were considered to have little intraductal spread on MRI, and these findings corresponded to the pathological findings. Sensitivity, specificity and accuracy of detecting intraductal spread were 88%, 75% and 78%, respectively. In order to evaluate the extent of intraductal spread, further study using more precise correlation with pathology is necessary. High-resolution MRI was also considered to be useful for evaluating the presence of multifocal or multicentric focies or muscle invasion.

Adenocarcinoma↗

PubMed1997

Characterization of stably transfected kidney epithelial cell line expressing rat H+/peptide cotransporter PEPT1: localization of PEPT1 and transport of beta-lactam antibiotics.

We established stably transfected LLC-PK1 cells expressing the rat H+/peptide cotransporter PEPT1 (designated LLC-rPEPT1) and examined membrane localization and uptake by rat PEPT1 of oral beta-lactam antibiotics. The LLC-rPEPT1 cells expressed a novel PEPT1 protein with an apparent molecular mass of 75 kdaltons, which was found in rat intestinal membranes. The cell surface biotinylation of LLC-rPEPT1 cell monolayers grown on membrane filters showed that PEPT1 was localized predominantly on the apical membranes and, to a lesser extent, on the basolateral membranes. The amount of [14C]glycylsarcosine uptake in LLC-rPEPT1 cell monolayers was 3-fold greater from the apical, than from the basolateral side, which suggested that rat PEPT1 expressed on both membranes was functionally active. LLC-rPEPT1 cells grown on plastic dishes transported differently charged oral cephalosporins such as ceftibuten (divalent anion lacking an alpha-amino group) and cephradine (zwitterion with an alpha-amino group) in the presence of an inward H+ gradient, whereas those transfected with the vector alone did not have transport activity. Kinetic analysis revealed that the LLC-rPEPT1 cells had much higher affinity for ceftibuten than for cephradine. Di- and tripeptides and bestatin, a dipeptide-like antineoplastic drug, potently inhibited the uptake of these cephalosporins. These results suggest that the LLC-rPEPT1 cells serve as a useful model with which to analyze the mechanisms involved in membrane targeting and substrate recognition by rat PEPT1.

Animals↗

PubMed1997

Cardiac extension of intravenous leiomyomatosis with successful resection.

A case of intravenous leiomyomatosis spreading to the right ventricle is described. A 28-year-old woman had been previously diagnosed as having a smooth muscle tumor of borderline malignancy after hysterectomy for a large uterine tumor, because of its unusual invasive character. Based on the above diagnosis, the patient had been managed clinically as having a uterine sarcoma. One year after her hysterectomy, a local recurrence in the pelvic cavity was detected. Two years later, the tumor appeared as a cardiac tumor causing syncope. The tumor was totally resected in two surgical stages, and the correct diagnosis of an intravenous leiomyomatosis was made. The diagnostic and operative considerations are reviewed and the preferred surgical procedure is discussed.

Adult↗

PubMed1997

Pancreatic lymph nodal and plexus micrometastases detected by enriched polymerase chain reaction and nonradioisotopic single-strand conformation polymorphism analysis: a new predictive factor for recurrent pancreatic carcinoma.

K-ras point mutations have been observed in approximately 90% of pancreatic carcinomas. We genetically analyzed cases of pancreatic regional lymph nodal and plexus micrometastases in invasive ductal carcinoma of the pancreas who were node negative or had metastases limited histopathologically to pancreaticoduodenal lymph nodes. These cases underwent curative resection in our institute. The utility of genetic analysis was compared with that of histopathological study, in terms of postoperative clinical outcome, as a predictive factor for recurrent pancreatic carcinoma. Samples for DNA extraction were obtained from formalin-fixed, paraffin-embedded specimens. A 0.5-microg quantity of DNA was subjected to enriched PCR and nonradioisotopic single-strand conformation polymorphism analysis. K-ras codon 12 mutations were detected in 83% (10 of 12) of invasive ductal carcinomas. In four cases, the genetic analysis of regional lymph nodal metastases and pancreatic plexus invasion of the pancreatic carcinoma yielded results concordant with those of histopathological analysis. In six cases, however, the metastases detected by genetic analysis were more advanced than was indicated by the histopathological examination. The survival rate of cases with metastases beyond the pancreaticoduodenal lymph nodes was significantly lower than that of cases with metastases limited to the pancreaticoduodenal lymph nodes or with no nodal involvement based on genetic analysis (P < 0.05). Intraoperative analysis of point mutations at K-ras codon 12 in the regional lymph nodes and the pancreatic plexus by enriched PCR/nonradioisotopic single-strand conformation polymorphism analysis is a highly accurate predictive factor for recurrent pancreatic carcinoma.

Adult↗