Biomedical subjects

S Kawauchi

Publications and source records attributed to S Kawauchi.

At least 19 recordsLinked to original sources

PubMed2006

Cytogenetic analysis of myxoid liposarcoma and myxofibrosarcoma by array-based comparative genomic hybridisation.

AIM: To investigate overall chromosomal alterations using array-based comparative genomic hybridisation (CGH) of myxoid liposarcomas (MLSs) and myxofibrosarcomas (MFSs). MATERIALS AND METHODS: Genomic DNA extracted from fresh-frozen tumour tissues was labelled with fluorochromes and then hybridised on to an array consisting of 1440 bacterial artificial chromosome clones representing regions throughout the entire human genome important in cytogenetics and oncology. RESULTS: DNA copy number aberrations (CNAs) were found in all the 8 MFSs, but no alterations were found in 7 (70%) of 10 MLSs. In MFSs, the most frequent CNAs were gains at 7p21.1-p22.1 and 12q15-q21.1 and a loss at 13q14.3-q34. The second most frequent CNAs were gains at 7q33-q35, 9q22.31-q22.33, 12p13.32-pter, 17q22-q23, Xp11.2 and Xq12 and losses at 10p13-p14, 10q25, 11p11-p14, 11q23.3-q25, 20p11-p12 and 21q22.13-q22.2, which were detected in 38% of the MFSs examined. In MLSs, only a few CNAs were found in two sarcomas with gains at 8p21.2-p23.3, 8q11.22-q12.2 and 8q23.1-q24.3, and in one with gains at 5p13.2-p14.3 and 5q11.2-5q35.2 and a loss at 21q22.2-qter. CONCLUSIONS: MFS has more frequent and diverse CNAs than MLS, which reinforces the hypothesis that MFS is genetically different from MLS. Out-array CGH analysis may also provide several entry points for the identification of candidate genes associated with oncogenesis and progression in MFS.

Adult↗

PubMed2006

Comparative genomic hybridization reveals genetic progression of oral squamous cell carcinoma from dysplasia via two different tumourigenic pathways.

To clarify the genetic pathway(s) involved in the development and progression of oral squamous cell carcinoma (OSCC), as well as the relationship between genetic aberrations and biological characteristics of OSCC tumours, comparative genomic hybridization was used to analyse genetic alterations in both primary OSCCs and adjacent dysplastic lesions of the same biopsy specimens from 35 patients. Gain of 8q22-23 was the most frequent alteration in both OSCC and mild dysplasia, and was considered the earliest event in the process of oral tumourigenesis. The average number of DNA sequence copy number aberrations (DSCNAs) increased with progression from mild dysplasia to invasive carcinoma (r = 0.737, n = 70, p < 0.001). OSCC samples were classified as having a large or small number of DSCNAs (OSCC-L, 21.4 +/- 4.7 DSCNAs or OSCC-S, 10.0 +/- 1.7 DSCNAs, respectively; p < 0.0001). Gains of 3q26-qter, 8q, 11q13, 14q, and 20q and losses of 4q, 5q12-22, 6q, 8p, 13q, and 18q22-qter were common to OSCC-L and OSCC-S. Gains of 5p15, 7p, 17q11-22, and 18p and losses of 3p14-21, 4p, and 9p were detected exclusively in OSCC-L. The average number of DSCNAs depended on whether the samples showed OSCC- L or dysplasia plus OSCC-L, or showed OSCC-S or dysplasia plus OSCC-S (p = 0.001). Gain of 5p15 and losses of 4p and 9p were detected even in dysplastic lesions adjacent to OSCC-L samples. Loss of 4p was associated with node metastasis by multivariate analysis (p = 0.013). OSCC-L tumours were more often T3-T4 stage tumours than T1-T2 stage tumours (p = 0.03). These findings suggest that two different types of OSCC, OSCC-L associated with high-stage cancer and OSCC-S associated with low-stage cancer, arise from different types of dysplasia via different genetic pathways.

Aged↗

PubMed2005

Global genomic changes induced by two-stage carcinogen exposure are precancerous alterations in non-transformed human liver epithelial THLE-3 cells.

Global genomic changes, including DNA aneuploidy, may be necessary for carcinogenesis; however, such genomic changes in precancerous cells have not been studied extensively. To identify early global genotypic changes associated with precancerous lesions, a non-transformed human liver epithelial cell line, THLE-3, was treated with benzo[a]pyrene or N-methyl-N-nitro-N-nitrosoguanidine, then by 12-O-tetradecanoyl-phorbol-13-acetate, resulting in morphological transformation of cells. We examined genotypic changes of the transformed cells by laser scanning cytometry, fluorescence in situ hybridization, and comparative genomic hybridization. Transformed fusiform cells displayed tetraploidy, chromosomal instability, DNA copy number aberrations. Cells with these changes were still in the precancerous stage. However, it is suggested that these global genomic changes including tetraploidization provide cells with genetic alterations leading to cancer.

Benzo(a)pyrene↗

PubMed2004

Differences between cytotoxicity in photodynamic therapy using a pulsed laser and a continuous wave laser: study of oxygen consumption and photobleaching.

Oxygen consumption at the targeted site has a significant effect on dosimetry in photodynamic therapy (PDT). However, oxygen consumption in PDT using a pulsed laser as a light source has not been clarified. We therefore investigated the dependence of cytotoxicity on the oxygen consumption and the photosensitizer photobleaching of PDT using a pulsed laser by comparing with that using a continuous wave (CW) laser. Mouse renal carcinoma cells (Renca) were incubated with a second-generation photosensitizer, PAD-S31. The cells were then irradiated with either a 670-nm nanosecond pulsed light from the 3rd harmonics of a Nd:YAG laser-pumped optical parametric oscillator with a peak fluence rate of approximately 1 MW/cm(2) at 30 Hz or a 670-nm CW diode laser with a total light dose of 40 J/cm(2). Regardless of laser source, cytotoxic effects exhibited cumulative dose responses to the photosensitizer ranging from 12 to 96 microg/ml. However, cytotoxic effect of PDT using the pulsed light was significantly less than that using the CW light with the photosensitizer concentrations of 24 and 48 microg/ml under identical fluence rates. During PDT, the cells exposed to the pulsed light consumed oxygen more slowly, resulting in a lower amount of oxygen consumption when compared with PDT using CW light. In accordance with oxygen consumption, the pulsed light induced significantly less photobleaching of the photosensitizer than the CW light did. These results indicate that the efficiency of PDT using pulsed light is less when compared with CW light, probably being related to suppressed oxygen consumption during the pulsed light irradiation.

Animals↗

PubMed2002

Critical parameters in the cytotoxicity of photodynamic therapy using a pulsed laser.

Photodynamic therapy (PDT) using a pulsed laser is becoming popular, but its cytotoxic effect is still not clear. We therefore studied the cytotoxicity of PDT using a pulsed laser by changing its irradiation parameters and compared the degrees of cytotoxicity with those of PDT using continuous-wave (CW) light sources. Mice renal cell carcinoma cells were incubated with PAD-S31, a water-soluble photosensitiser of which the excitation peak is 670 nm, and were then irradiated with either a tungsten lamp, a CW diode laser, or a nanosecond pulsed Nd:YAG laser-based optical parametric oscillator system. When the PAD-S31 concentration and total light dose were constant (12 micro g/ml and 40 J/cm(2), respectively), the CW laser caused fluence rate-dependent decrease in cellular proliferation until the fluence rate reached 90 mW/cm(2), at which point inhibition of cellular proliferation was more than 80%. The cytotoxicity then became almost saturated at fluence rates of>90 mW/cm(2). On the other hand, inhibition of cellular proliferation in samples irradiated with the pulsed laser reached 80% even at the fluence rate of 15 mW/cm(2), and, interestingly, the cytotoxicity paradoxically decreased with increase in the fluence rate. Moreover, the cytotoxicity in the PDT using the pulsed laser depended on the repetition rate. The inhibition of cellular proliferation by PDT using 30-Hz irradiation was greater than that by PDT using 5-Hz irradiation when the same fluence rates were used. These results suggest that the efficacy of PDT using a pulsed laser depends considerably on fluence rate and repetition rate.

Animals↗

PubMed2001

Examination of oncogene amplification by genomic DNA microarray in hepatocellular carcinomas: comparison with comparative genomic hybridization analysis.

To identify amplified oncogenes involved in hepatocellular carcinomas (HCC), we applied a genomic DNA microarray spotted with 57 oncogenes to 20 HCCs. Aberrations in DNA copy number also were analyzed by comparative genomic hybridization (CGH) using an aliquot of DNA samples. In 5 of 20 HCCs, only 6 oncogenes (CCND1, FGF3/FGF4, SAS/CDK4, TERC, MET, and MYC) were amplified, whereas in the remaining 15 tumors no oncogenes were amplified. A comparison of DNA microarray and conventional CGH analyses showed that, although 5 of 6 amplified oncogenes shown by microarray were located in chromosomal regions shown by CGH to have increased DNA copy numbers, not all genes located in such chromosomal regions were affected. One of the amplified oncogenes (SAS/CDK4) was found in a chromosomal region that was undetected by CGH. We, therefore, conclude that amplification of the oncogenes examined in this series is not directly implicated in hepatocellular carcinogenesis.

Adult↗

PubMed2001

Expression of p21(WAF1/CIP1) and p53 proteins in gastric carcinoma: its relationships with cell proliferation activity and prognosis.

The expressions of p21(WAF1/CIP1), p53 proteins, and Ki-67 antigen were investigated immunohistochemically in 190 primary gastric carcinomas. Of the 190 tumors, 40.5% positively expressed p21(WAF1/CIP1) and 42.1% positively expressed p53. The expression of p21(WAF1/CIP1) was significantly associated with clinicopathological factors including gender, tumor size, status of lymph node, and clinicopathological stage (P<0.05 for all), but p21(WAF1/CIP1) expression showed no clear correlation with Ki-67 labeling index. The mean Ki-67 labeling index was significantly higher in p53-positive cases than p53-negative cases (P<0.0001). However, among the clinicopathological factors examined, expression of p53 correlated only with age. Univariate and multivariate survival analyses revealed that clinicopathological stage (P<0.001) and expression status of p21(WAF1/CIP1) (P<0.05) were independent prognostic factors. Neither the expression status of p53 nor the Ki-67 labeling index, however, influenced the prognosis of patients with gastric cancer.

Adult↗

PubMed2001

Body temperature dependency in baclofen-induced gastric acid secretion in rats relation to capsaicin-sensitive afferent neurons.

Body temperature dependency in gastric functional responses to baclofen, a GABA(B) agonist, such as acid secretion, mucosal blood flow (GMBF) and motor activity, was examined in urethane-anesthetized rats under normal (37+/-1 degrees C) and hypothermic (31+/-1 degrees C) conditions. A rat stomach was mounted in an ex-vivo chamber, perfused with saline, and the acid secretion was measured using a pH-stat method, simultaneously with GMBF by a laser Doppler flowmeter. Gastric motility was measured using a miniature balloon as intraluminal pressure recordings. Intravenous administration of baclofen significantly increased acid secretion at the doses > 0.3 mg/kg under hypothermic conditions, yet it caused a significant stimulation only at doses > 10 mg/kg under normothermic conditions. The increases in gastric motility and GMBF were similarly induced by baclofen, irrespective of whether the animals were subjected to normothermic or hypothermic conditions. These functional responses to baclofen under hypothermic conditions were totally attenuated by either bilateral vagotomy or atropine (3 mg/kg, s.c.). Baclofen at a lower dose (1 mg/kg i.v.) significantly increased the acid secretion even under normothermic conditions when the animals were subjected to chemical deafferenation of capsaicin-sensitive neurons or pretreatment with intracisternal injection of CGRP8-37 (30 ng/rat). These results suggest that 1) gastric effects of baclofen are dependent on body temperature in stimulating acid secretion but not GMBF or motor activity, 2) the acid stimulatory action of baclofen is enhanced under hypothermic conditions, and 3) the suppression of baclofen-induced acid response under normothermic conditions may be related to capsaicin-sensitive afferent neuronal activity, probably mediated by central release

Animals↗

PubMed2001

Low expression of p27(Kip1), a cyclin-dependent kinase inhibitor, is a marker of poor prognosis in synovial sarcoma.

BACKGROUND: Low expression of p27(kip1), a dominant cyclin-dependent kinase inhibitor involved in G1-S transition of the cell cycle, recently has been reported to be associated with aggressive tumor growth. It has been shown that active cell proliferation alludes to poor prognosis in patients with synovial sarcoma. However, to the authors' knowledge, little is known about the clinicopathologic significance of p27(kip1) in synovial sarcoma. METHODS: p27(kip1) expression was examined immunohistochemically in 55 cases of primary synovial sarcoma, and the relations between p27(kip1) expression and several cell proliferation markers, i.e., mitotic index (MI), Ki-67 labeling index (Ki-67 LI), and clinicopathologic parameters related to poor prognosis, were determined. Univariate and multivariate survival analyses were performed to evaluate the prognostic significance of p27(kip1) expression in synovial sarcomas. RESULTS: p27(kip1) labeling index (p27(kip1) LI) correlated inversely with MI (r = -0.44, P = 0.0007) and Ki-67 LI (r = -0.63, P < 0.0001). Of the clinicopathologic parameters examined, tumor necrosis (P = 0.019) and American Joint Committee on Cancer (AJCC) stage (P = 0.021) correlated significantly with p27(kip1) LI. Survival analysis showed that p27(kip1) LI was an independent prognostic factor for overall survival in patients with synovial sarcoma (P = 0.0031). CONCLUSIONS: The study results suggested that low expression of p27(kip1) may be useful as a marker of poor-prognosis synovial sarcoma.

Adolescent↗

PubMed2001

Comparative genomic hybridization analysis of genetic aberrations associated with development and progression of biliary tract carcinomas.

BACKGROUND: Little is known about genetic aberrations associated with development and progression of biliary tract carcinomas. METHODS: To study chromosomal aberrations associated with development and progression of biliary tract carcinomas, the authors used comparative genomic hybridization to examine 50 such carcinomas. RESULTS: Gains in part or in whole of chromosomes 1q, 8q, and 20q and losses of 5q, 8p, 9p, and 18q were detected frequently in early stage (T1/T2 classification) biliary tract carcinomas (> or = 40% of 19 early stage tumors), and they also were found in advanced stage (T3/T4 classification) tumors. In particular, loss of 9p was the most frequently observed aberration in both early stage (15 of 19; 78%) and advanced stage tumors (21 of 31; 68%). The frequencies of gains of 7p12-p14 (P < 0.003), 7p21-pter (P < 0.007), and 7q31 (P < 0.01) differed significantly between biliary tract carcinoma with and without distant metastasis. Also, gains of 5p and 19q13 and loss of 6q14-q16 were more frequent in tumors with lymph node metastasis than in those without it (P < 0.02). CONCLUSIONS: It is likely that loss of 9p is one of the genetic aberrations critical for the development of biliary tract carcinoma, whereas gains of 5p, 7p, 7q, and 19q and loss of 6q are considered later events associated with tumor progression and are thought to confer metastatic potential to biliary tract carcinomas.

Adult↗

PubMed2001

Nanosecond, high-intensity pulsed laser ablation of myocardium tissue at the ultraviolet, visible, and near-infrared wavelengths: in-vitro study.

BACKGROUND AND OBJECTIVE: A large number of clinical trials of transmyocardial laser revascularization (TMLR) have been conducted to treat severe ischemic heart diseases. A variety of laser sources have been used or tested for this treatment, however, no comprehensive study has been performed to reveal the mechanism and the optimum laser irradiation condition for the myocardium tissue ablation. There have been reported limited experimental data of the high-intensity pulsed laser ablation of myocardium tissues. STUDY DESIGN/MATERIALS AND METHODS: A 1064-nm Q-switched Nd:YAG laser and its 2nd (532 nm), 3rd (355 nm), and 4th (266 nm) harmonics were used for ablation experiments. At each wavelength, 25 laser pulses irradiated the porcine myocardium tissue samples at a constant laser intensity (peak laser power divided by laser spot area) of approximately 2 GW/cm(2) and the ablation depths were measured. During ablation, laser-induced optical and acoustic emissions were measured to investigate the ablation mechanism at each laser wavelength. For the ablated tissues, histological observation was made with a polarization optical microscope. RESULTS: It was shown that the ablation efficiency did not directly depend on the linear absorption coefficient of the tissue; the ablation depth was maximized at 355 and 1064 nm, and minimized at 532 nm. Strong laser-induced optical and acoustic emissions were observed for the 266- and 1064-nm laser irradiations. The histology showed that thermal denaturation of the tissue near the ablation walls decreased with decreasing wavelength for 266, 355, and 532 nm, but it was limited for 1064 nm. CONCLUSION: At the laser intensity of approximately 2 GW/cm(2), ablation characteristics were drastically changed for the different laser wavelengths. The results indicated that for 266, 355, and 532 nm, the tissue removal was achieved mainly through a photothermal process, but for 266 nm the intense laser-induced plasma formation would result in a reduced laser energy coupling to the tissue. For 1064 nm, a photodisruption was most probable as a dominant tissue removal process. Because of the high ablation rate and limited thermal denaturation, the 355- and 1064-nm lasers could be potential laser sources for TMLR, although further investigation is needed to discuss the clinical issues.

Angioplasty, Laser↗

PubMed2001

A single amino acid change at Leu-188 in the reverse transcriptase of HIV-2 and SIV renders them sensitive to non-nucleoside reverse transcriptase inhibitors.

Non-nucleoside reverse transcriptase inhibitors (NNRTIs) are selective for human immunodeficiency virus type 1 (HIV-1) and generally not effective on HIV-2 or simian immunodeficiency virus (SIV). Only SIVagm was found to be sensitive to NNRTIs. When the amino acid differences in RT between SIVmac and SIVagm were compared with the known amino acid substitutions of NNRTI-resistance variants of HIV-1, we came to consider that the amino acid residue Leu-188 of HIV-2 and SIVmac might be related to their resistance to NNRTIs. To test this hypothesis, we substituted Leu-188 to Cys or Tyr in HIV-2 and SIVmac, and examined sensitivity of the mutant molecular clones to NNRTIs. The L188Y mutant of HIV-2 became completely sensitive to delavirdine and efavirenz, while that of SIVmac was also significantly sensitive to these NNRTIs. We further isolated NNRTI-resistant variants from these mutant viruses and determined amino acid substitutions in RT. The roles of the observed substitutions in NNRTI-resistance were further confirmed by site-directed mutagenesis. Our study reveals the crucial role of L188 in the natural resistance of HIV-2 and SIVmac to NNRTIs. Furthermore, the observed substitutions in RT of HIV-2 and SIVmac support the common mechanism of action of NNRTIs against HIV-1, HIV-2 and SIV.

Alkynes↗

PubMed2001

Identification of 197 genetic variations in six human methyltranferase genes in the Japanese population.

Methylation is an important event in the biotransformation pathway for many drugs and xenobiotic compounds. We screened DNA from 48 Japanese individuals for single-nucleotide polymorphisms (SNPs) in six methyltransferase (MT) genes (catechol-O-MT, COMT; guanidinoacetate N-MT, GAMT; histamine N-MT, HNMT; nicotinamide N-MT, NNMT; phosphatidylethanolamine N-MT, PEMT; and phenylethanolamine N-MT, PNMT) by direct sequencing of their entire genomic regions except for repetitive elements. This approach identified 190 SNPs and seven insertion/deletion polymorphisms among the six genes. Of the 190 SNPs, 33 were identified in the COMT gene, 6 in GAMT, 41 in HNMT, 8 in NNMT, 98 in PEMT, and 4 in PNMT. Nine were located in 5' flanking regions, 156 in introns, 10 in exons, and 15 in 3' flanking regions. These variants may contribute to a more precise understanding of possible correlations between genotypes and disease-susceptibility phenotypes or risk for side effects from drugs.

3' Untranslated Regions↗

PubMed2001

Amplification of 3q26 approximately qter correlates with tumor progression in head and neck squamous cell carcinomas.

Biological characteristics of malignant tumors including head and neck squamous cell carcinoma (HNSCC) are greatly affected by genetic alterations. However, the relationship between chromosomal aberrations and pathologic tumor stage in HNSCC has not been elucidated. In 32 patients, DNA sequence copy number aberrations (DSCNA) were surveyed by comparative genomic hybridization (CGH) combined with a microdissection method. The average number of DSCNA was 15.3 per tumor and increased with tumor stage (P<.05). DNA copy number gain was detected at 3q26 approximately qter in 29 tumors (91%), and 13 of these tumors displayed marked DNA amplification. Tumor stage was linked with this amplification (P<.05). The increase in DSCNA and amplification of 3q26 approximately qter are likely to be useful markers for estimating tumor progression in HNSCC.

Adult↗

PubMed2001

Defective development of secretory neurones in the hypothalamus of Arnt2-knockout mice.

BACKGROUND: Within the basic region-helix-loop-helix (bHLH)-PAS family of transcription factors, Arnt and Arnt2 play unique roles; these two factors not only heterodimerize with themselves, but also with other members of this family and they act as transcription regulators which bind to specific DNA elements. Whereas Arnt is broadly expressed in various tissues, the expression of Arnt2 is known to be limited to the neural tissues. RESULTS: To elucidate the function of Arnt2 in detail, we cloned the mouse Arnt2 gene and its gene structure was determined. We subsequently generated germ line Arnt2 mutant mice by gene targeting technology. Heterozygous Arnt2 mice were viable, but homozygous Arnt2 gene knockout mice died shortly after birth. Histological and immunological analyses revealed that the supraoptic nuclei (SON) and the paraventricular nuclei (PVN) are hypocellular. Moreover, secretory neurones identified by the expression of neurosecretory hormone such as arginine vasopressin, oxytocin, corticotrophin-releasing hormone and somatostatin are completely absent in SON and PVN in the mutant Arnt2 mice. Consistent with these observations, prospective SON and PVN neurones which express Brn2 appeared around E13.5 in the mantle zone, but no neurones which expressed the neurosecretory hormones were found in the SON and PVN regions. CONCLUSIONS: These data show that the transcription factor Arnt2 controls the development of the secretory neurones at the later or final stages of differentiation rather than at the beginning stage. Strikingly similar observations have been reported with the Sim1 deficient mice. Taken together, our results demonstrate that Arnt2 is an indispensable transcription factor for the development of the hypothalamus, and suggest that Arnt2 is an obligatory partner molecule of Sim1 in the developmental process of the neuroendocrinological cell lineages.

Amino Acid Sequence↗

PubMed2001

Combined examination of p27(Kip1), p21(Waf1/Cip1) and p53 expression allows precise estimation of prognosis in patients with gastric carcinoma.

AIMS: In order to estimate the prognostic values of p27(Kip1), p21(Waf1/Cip1), and p53, alone and in combination, we investigated immunohistochemically the expression of p27(Kip1), p21(Waf1/Cip1), and p53 proteins in gastric carcinomas. METHODS AND RESULTS: The expression of p27(Kip1), p21(Waf1/Cip1), and p53 was immunohistochemically examined in 140 gastric carcinomas. Positive expression of p27(Kip1) and p21(Waf1/Cip1) correlated significantly with a favourable prognosis (P < 0.05), whereas, positive expression of p53 tended to correlate with poor prognosis. Multivariate survival analysis revealed that TNM stage of tumour (P < 0.001), lymph node state (P=0.005), and p27(Kip1) expression (P=0.006) were independent prognostic factors. A striking stratification of mortality rate was found when patients were divided into four groups according to the expression of p21(Waf1/Cip1) and p27(Kip1). The mortality rate was higher in patients with both p21(Waf1/Cip1)- and p27(Kip1)-negative gastric carcinoma than in patients with one or both positive carcinomas (P < 0.01). In addition, if the four p21(Waf1/Cip1)/p27(Kip1) groups were compared based on p53 status, p53+ cases tended to have a higher mortality rate than p53- cases. CONCLUSION: Our results suggest that low expression of both p27(Kip1) and p21(Waf1/Cip1), could be useful as markers of poorer prognosis, and the combined examination of p27(Kip1), p21(Waf1/Cip1) and p53 expression allows reliable estimation of prognosis for patients with gastric carcinoma.

Adult↗

PubMed2001

Imported malaria in a Japanese male: an autopsy report.

Fatal cases of malaria are rare in Japan. We report a case of a 47-year-old Japanese man with Plasmodium falciparum malaria. The patient was examined because of fever and headache after a trip to Africa. He was diagnosed with malaria. Chemotherapy begun on day three decreased the percentage of infected red blood cells (RBC) from 25% to 2%, but the patient fell into coma on the same day. The patient was considered brain dead for 3 days before he died, and he was autopsied on day nine. Brain hemispheres were preserved and swollen with meningeal congestion. The ventral area of the pons and medulla oblongata were softened, and the tonsils of the cerebellum were softened and herniated. The spleen was blackish, enlarged and showed a small infarction. The liver was yellowish and enlarged. Many infected RBC were seen in the capillaries of the brain and malaria pigments were seen in the spleen and liver. DNA of P. falciparum was detected by polymerase chain reaction from paraffin-embedded brain materials, however, the DNA could not be detected in other organs. Besides malaria, the patient had latent primary thyroid cancer, which was a small and invasive papillary carcinoma.

Animals↗

PubMed2001

Expression of p53 protein as a prognostic indicator of reduced survival time in diffuse-type gastric carcinoma.

To determine whether p53 expression is different in intestinal and diffuse types of gastric carcinoma, we investigated p53 immunohistochemical expression in 178 primary gastric carcinomas. Overexpression of p53 was observed in 50 out of 100 intestinal-type tumors (50.0%) and in 27 out of 78 diffuse-type tumors (34.6%). A significant difference was found in the timing of p53 overexpression between the two types of carcinomas. Overexpression of p53 occurred often in the early stage of intestinal-type tumors, and there was no significant difference in expression between early and advanced cancers. In contrast, p53 overexpression did not occur often in the early stage of diffuse-type tumors, but it increased progressively as the tumor advanced. Analysis of patient survival revealed that p53 overexpression correlates significantly with a poor prognosis in diffuse-type gastric carcinoma (P = 0.003) but not in intestinal-type. Multivariate analysis showed that only pathological stage was an independent prognostic indicator. Our results suggest that p53 overexpression plays a different role in tumor carcinogenesis and progression of these two types of gastric cancers.

Adenocarcinoma↗