Clinical features of the posterior horn tear in the medial meniscus

INTRODUCTION

A lower threshold of suspicion is necessary for the appropriate diagnosis of a posterior horn tear in the medial meniscus. In these cases, radial tears or meniscus detachment from its insertion follow minor trauma and precipitate severe knee pain in middle-aged and elderly patients. The purpose of this paper is to demonstrate the key points for diagnosis through examination of the clinical features of this tear.

MATERIALS AND METHODS

Arthroscopic examination of 250 knees with medial meniscus tears (and no ligamentous injuries; over 40 years old) identified 26 knees (26 tears) with a posterior horn tear. Of these 26 tears, 16 were radial, and 10 were detached.

RESULTS

Eighty-five percent of patients could recall discrete events that preceded the pain. They described these events as a click or a feeling of shock. Afterwards, most patients complained of severe pain or giving way. Hydrarthrosis involving more than 5 ml was present in 81%. Most radiographs (92%) appeared nearly normal.

CONCLUSION

It is important to note that this type of tear of the posterior horn in the medial meniscus is not rare. Because this area is difficult to visualize arthroscopically, it may be overlooked unless the threshold of suspicion is lowered.

MotPS is the stator-force generator for motility of alkaliphilic Bacillus, and its homologue is a second functional Mot in Bacillus subtilis

The stator-force generator that drives Na+-dependent motility in alkaliphilic Bacillus pseudofirmus OF4 is identified here as MotPS, MotAB-like proteins with genes that are downstream of the ccpA gene, which encodes a major regulator of carbon metabolism. B. pseudofirmus OF4 was only motile at pH values above 8. Disruption of motPS resulted in a non-motile phenotype, and motility was restored by transformation with a multicopy plasmid containing the motPS genes. Purified and reconstituted MotPS from B. pseudofirmus OF4 catalysed amiloride analogue-sensitive Na+ translocation. In contrast to B. pseudofirmus, Bacillus subtilis contains both MotAB and MotPS systems. The role of the motPS genes from B. subtilis in several motility-based behaviours was tested in isogenic strains with intact motAB and motPS loci, only one of the two mot systems or neither mot system. B. subtilis MotPS (BsMotPS) supported Na+-stimulated motility, chemotaxis on soft agar surfaces and biofilm formation, especially after selection of an up-motile variant. BsMotPS also supported motility in agar soft plugs immersed in liquid; motility was completely inhibited by an amiloride analogue. BsMotPS did not support surfactin-dependent swarming on higher concentration agar surfaces. These results indicate that BsMotPS contributes to biofilm formation and motility on soft agar, but not to swarming, in laboratory strains of B. subtilis in which MotAB is the dominant stator-force generator. BsMotPS could potentially be dominant for motility in B. subtilis variants that arise in particular niches.

Which cartilage is regenerated, hyaline cartilage or fibrocartilage? Non-invasive ultrasonic evaluation of tissue-engineered cartilage

OBJECTIVE

To investigate ultrasonic evaluation methods for detecting whether the repair tissue is hyaline cartilage or fibrocartilage in new cartilage regeneration therapy.

METHODS

We examined four experimental rabbit models: a spontaneous repair model (group S), a large cartilage defect model (group L), a periosteal graft model (group P) and a tissue-engineered cartilage regeneration model (group T). From the resulting ultrasonic evaluation, we used %MM (the maximum magnitude of the measurement area divided by that of the intact cartilage) as a quantitative index of cartilage regeneration. The results of the ultrasonic evaluation were compared with the histological findings and histological score.

RESULTS

The %MM values were 61.1 +/- 16.5% in group S, 29.8 +/- 15.1% in group L, 36.3 +/- 18.3% in group P and 76.5 +/- 18.7% in group T. The results showed a strong similarity to the histological scoring.

CONCLUSION

The ultrasonic examination showed that all the hyaline-like cartilage in groups S and T had a high %MM (more than 60%). Therefore, we could define the borderline between the two types of regenerated cartilage by the %MM.

Can ultrasound predict histological findings in regenerated cartilage?

OBJECTIVE

To evaluate regenerated articular cartilage quantitatively by introducing an ultrasonic probe into the knee joint under arthroscopy and analysing the A-mode echogram by means of wavelet transformation.

METHODS

Three experimental rabbit models (spontaneous repair model, large cartilage defect model, treatment model) were examined using our ultrasonic evaluation system and a histological grading scale. From resulting wavelet map, the percentage of maximum magnitude was selected as the quantitative index of the ultrasonic evaluation system.

RESULTS

The percentage maximum magnitude in the spontaneous repair model was 61.1%, that in the large defect model was 29.8% and that in the treatment model was 36.3%. There was modest correlation between the percentage maximum magnitude and the histological grading scale (r = -0.594)

CONCLUSION

Our findings indicate that ultrasound analysis can predict the microstructure of regenerated cartilage.

The presynaptic modulation of glutamate release and the membrane dysfunction induced by in vitro ischemia in rat hippocampal CA1 neurons

Superfusion with an oxygen and glucose deprived medium (in vitro ischemia) of rat hippocampal CA1 pyramidal neurons in tissue slices produced a rapid depolarization within 5 min and thereafter showed no functional recovery (irreversible membrane dysfunction), even if oxygen and glucose were reintroduced. We previously suggested that such a rapid depolarization is triggered by the accumulation of extracellular glutamate (Glu). As a result, we examined the effects of either the activation or inhibition of presynaptic receptors, which modulate Glu release from the nerve terminal, on the potential change produced by in vitro ischemia. The adenosine A1 receptor antagonist, 8-cyclopenthyl theophylline, A2a receptor antagonist, ZM241385, and A2b receptor antagonist, alloxazine, did not significantly alter either the latency or the maximal slope of the rapid depolarization. In addition, the GABAB receptor antagonist, 2-hydroxysaclofen, or the metabotropic Glu receptor type 4 antagonist, alpha-methylserine-O-phosphate, did not change either the latency or the maximal slope. The adenosine A(1) receptor agonist, 2-chloro-N6-cyclopentyladenosine, A2a receptor agonist, CGS2168, or A2b receptor agonist, 5'-(N-ethylcarboxamido)-adenosine, did not affect these parameters either. None of these drugs restored the membrane potential to the pre-exposure level after the reintroduction of oxygen and glucose. Simultaneous intracellular recordings from CA1 and CA3 pyramidal neurons in the same slices revealed the membrane of the CA3 neurons to be hyperpolarized when a rapid depolarization occurred in the CA1 neurons. These results suggest that presynaptic Glu release does not accelerate during the generation of the rapid depolarization induced by in vitro ischemia.

Extrusion of intracellular calcium ion after in vitro ischemia in the rat hippocampal CA1 region

Simultaneous recordings of intracellular Ca(2+) ([Ca(2+)](i)) signal and extracellular DC potential were obtained from the CA1 region in 1-[6-amino-2-(5-carboxy-2-oxazolyl)-5-benzofuranyloxy]-2-(2-amino-5-methylphenoxy)-ethane-N,N,N',N'-tetraacetic acid penta-acetoxymethyl ester (Fura-2/AM)-loaded rat hippocampal slices. Superfusion with oxygen- and glucose-deprived medium (in vitro ischemia) for 5-6 min produced a rapid rise of the [Ca(2+)](i) level in the stratum radiatum (rising phase of the [Ca(2+)](i) signal), which occurred simultaneously with a rapid negative DC potential (rapid negative potential). When oxygen and glucose were reintroduced, the increased [Ca(2+)](i) signal diminished rapidly (falling phase of the [Ca(2+)](i) signal) during the generation of a slow negative DC potential (slow negative potential), which occurred within 1 min from the onset of the reintroduction. Thereafter, the [Ca(2+)](i) signal partially and the slow negative potential completely returned to the preexposure level approximately 6 min after the reintroduction. The changes in [Ca(2+)](i) signal during and after in vitro ischemia were very similar to the changes in the membrane potential of glial cells. The rising and falling phases of [Ca(2+)](i) signal corresponded to the rapid depolarization and a depolarizing hump, respectively, in the repolarizing phase of glial cells. A prolonged application of in vitro ischemia or a reintroduction of either glucose or oxygen suppressed the falling phase after ischemic exposure. The application of ouabain (30 microM) generated both a rapid negative potential and a rapid elevation of [Ca(2+)](i), but no slow negative potential or rapid reduction in [Ca(2+)](i) were observed. When oxygen and glucose were reintroduced to slices in the Na(+)-free or ouabain- or Ni(2+)-containing medium, the falling phase was suppressed. The falling phase was significantly accelerated in Ca(2+)- and Mg(2+)-free with EGTA-containing medium. In contrast, the falling phase was significantly slower in the Ca(2+)-free with high Mg(2+)- and EGTA-containing medium. The falling phase of the [Ca(2+)](i) signal after ischemic exposure is thus considered to be primarily dependent on the reactivation of Na(+), K(+)-ATPases, while the extrusion of cytosolic Ca(2+) via the forward-mode operation of Na(+)/Ca(2+) exchangers in glial cells is thought to be directly involved in the rapid reduction of [Ca(2+)](i) after ischemic exposure.

Localization of group IB phospholipase A(2) isoform in the gills of the red sea bream, Pagrus (Chrysophrys) major

We previously reported that PLA(2) activity in the gills is higher than that in other tissues in red sea bream and purified PLA(2) from the gills belongs to the group IB PLA(2) as well as other red sea bream PLA(2)s. In this study, we reconfirmed that the level of PLA(2) activity is extremely high in the gills compared with other tissues, and gill PLA(2) was detected only in the gills by immunoblotting and inhibition test using anti-gill PLA(2) monoclonal antibody. The level of PLA(2) activity and protein expression in the gills are well correlated. Fish can be roughly divided into high and low groups based on the level of PLA(2) activity. Gill PLA(2) was detected in the gills of the high group, but not the low group by immunoblotting. In the gills of the high group, gill PLA(2) was detected in the mucous cells and pavement cells located on the surface of gill epithelia by immunohistochemistry. On the other hand, positive signals were observed only in the mucous cells by in situ hybridization. We also isolated inactive proPLA(2), having AR propeptide, preceding the mature enzyme from the gill extract. These results suggest that gill PLA(2) is synthesized as an inactive proPLA(2) in the mucous cells and is secreted to the surface of gill epithelia.

Aberrations in the fragile histidine triad (FHIT) gene in idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) seems to be closely associated with lung carcinogenesis. To identify the genetic characteristics of precancerous IPF lesions in the peripheral lung, we performed PCR-based microsatellite analysis with DNA extracted from microdissected tissues; fluorescent in situ hybridization (FISH) analysis of the fragile histidine triad (FHIT) gene and immunohistochemical analysis of Fhit protein expression in samples of metaplasias and bronchiolar epithelia obtained from patients with IPF. We used four microsatellite markers of the FHIT gene within or flanking the FHIT gene on chromosome 3p for loss of heterozygosity (LOH) analysis. LOH of the FHIT locus was frequently found among the lesions of metaplasias and bronchiolar epithelia in the patients with IPF [62 (52%) of 119 informative lesions]. Fifty-four (73%) of the 74 lesions of metaplasias and bronchiolar epithelia obtained from the IPF patients with lung carcinoma and 8 (17%) of the 46 samples obtained from the IPF patients without lung carcinoma showed LOH at the FHIT gene (P < 0.0001). We confirmed allelic loss in the metaplasias and bronchiolar epithelia of IPF by FISH analysis of the FHIT gene. Additionally, the level of Fhit protein expression in the metaplastic cells of IPF was frequently reduced. Our findings suggest that allelic loss of the FHIT gene may be involved in carcinogenesis in the peripheral lung of patients with IPF.

p14(ARF) modulates the cytolytic effect of ONYX-015 in mesothelioma cells with wild-type p53

ONYX-015 has been reported to kill selectively tumor cells lacking functional p53. Genetic alterations of INK4a/ARF locus, which is a predominant event in malignant pleural mesothelioma, may result in loss of p14(ARF) and subsequent disruption of p53 pathway in cancer cells. In the present study, ONYX-015 was able to kill three mesothelioma cell lines (H28, H513, and 211H) with wild-type p53 but lacking p14(ARF). In contrast, MS-1 mesothelioma cells, which expressed both p53 and p14(ARF), were resistant to ONYX-015. Introducing p14(ARF) gene into the H28 cell, a mesothelioma cell without p14(ARF) expression, significantly increased the resistance of this cell line to the cytolytic effect of ONYX-015. Our results suggest that human mesotheliomas with wild-type p53 yet lacking p14(ARF) are potential candidates for ONYX-015 therapy.

Altered expression of several genes in highly metastatic subpopulations of a human pulmonary adenocarcinoma cell line

Non-small cell lung cancer is associated with approximately 85% mortality due to its high metastatic potential. Therapeutic efforts have failed to produce a significant improvement in prognosis. In this situation, a better understanding of the key factors of metastasis may be useful for designing new molecular targets of therapy. In order to identify these factors, we compared the expression profiles of two subpopulations of an adenocarcinoma cell line with a high metastatic potential, PC9/f9 and PC9/f14, with the parent cell line, PC9, using a cDNA array. The expression of 15 genes was found to be significantly enhanced or reduced in the highly metastatic subpopulations. The expression of matrix metalloproteinase-2 (MMP-2), plasminogen activator inhibitor-1 (PAI-1) and interleukin-1 (IL-1 alpha) were upregulated in the highly metastatic subpopulations, while the expression of carcinoembryonic antigen (CEA), caspase-5, Fas ligand, Prk/FNK, cyclin E, cyclin B1, Ki-67, proliferating cell nuclear antigen (PCNA), Smad4, macrophage proinflammatory human chemokine-3 alpha (MIP-3 alpha)/LARC, Met and CD44 were downregulated. Data from the literature suggest that the altered expression of MMP-2, PAI-1, IL-1 alpha, CEA, caspase-5, Fas ligand, Prk/FNK and Smad4 promotes the highly metastatic phenotype. The differential expression of these genes was confirmed by Northern blot analysis, standard reverse transcription-polymerase chain reaction (RT-PCR) and real-time quantitative RT-PCR. This analysis in subpopulations of a lung cancer cell line indicated that the highly metastatic potential of lung cancer may be induced not by an alteration in the expression of a single gene, but by the accumulation of alterations in the expression of several genes involved in extracellular matrix (ECM) adhesion disruption, ECM degradation, escape from apoptosis, and resistance to transforming growth factor-beta(1) (TGF-beta(1)). Strategies for inhibiting metastasis of pulmonary adenocarcinoma should be designed accordingly.

Unchanged frequency of loss of heterozygosity and size of the deleted region at 8p21-23 during metastasis of lung cancer

The genetic mechanisms involved in lung cancer development and progression are beginning to be understood. Many studies have documented frequent loss of heterozygosity (LOH) at specific chromosomal regions in cancer cells; this implies that tumor suppressor genes (TSG) are usually present in those regions. Recently, it has been reported that LOH or chromosomal deletions at chromosome 8p21-23 represent early events frequently occurring in lung cancer. In addition, the size of these chromosome 8 deletions, as well as their frequency, was also reported to increase during lung cancer progression. To determine the spectrum and frequency of alterations of chromosome 8p21-23 in human lung cancer and whether these increase with progression of the tumors, we performed LOH analysis of chromosome 8p and 3p in the genomic DNA from cells from primary and metastatic sites of lung cancer, as well as from normal lung. We studied 35 subjects with primary lung cancer including 30 tumors with distant metastasis. Detection of allelic deletion utilized a PCR-based approach of microsatellite polymorphism analysis, which was performed using the microsatellite markers D8S1130, D8S1106, D8S511, D8S1827, D8S549, D8S261, LPL, D8S258, D8S136, NEFL, D3S1295, D3S1313, D3S1234, D3S1300, D3S1351, D3S1339, and D3S1340. The overall allelic deletion rates were 10 of 28 (35.7%) at 8p and 13 of 33 (39.4%) at 3p. The allelic deletions in the primary cancer and its metastatic sites were in each case identical in both frequency and size of the deleted regions. In our analysis, 8p21-23 deletions were not always associated with 3p deletions in primary lung cancer. These results therefore suggest that allelic deletion at chromosome 8p21-23 is an early and frequent event in the carcinogenesis and development of lung cancer, independent of chromosome 3p deletion. However, a continuing increase in the frequency of LOH at 8p21-23 and in the size of the deleted region rarely occurs during the process of metastasis.

Genomic structure of the human MAD2 gene and mutation analysis in human lung and breast cancers

Some of the many human cancers that exhibit chromosomal instability also carry mutations in mitotic checkpoint genes and/or reveal reduced expression of some of those genes, such as hMAD2. To facilitate investigation of alterations of hMAD2, we determined its genomic structure and intronic primers designed to amplify the entire coding region. Since general impairment of the mitotic checkpoint is frequently reported in lung cancers, and reduced expression of hMAD2 has been reported in breast cancers as well, we searched for mutations throughout the coding sequence of this gene in the genomic DNA of 30 primary lung tumors, 30 lung-cancer cell lines and 48 primary breast cancers. Our approach, which involved polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis and direct sequencing, revealed nucleotide variants in only two of the 108 specimens. One was a cytosine-to-adenine substitution 3 bp upstream of exon 4 that occurred in one lung cancer cell line and one primary breast tumor, a change that did not alter transcriptional sequence. The other was an adenine-to-guanine substitution within exon 4, of the same lung cell line; this change already had been reported as a polymorphism. The results suggested that the hMAD2 gene is not commonly mutated in either lung nor breast cancers. Further studies should focus on other mechanisms that might account for reduced expression of the hMAD2 gene, and/or pursue analyses of other mitotic checkpoint genes for mutations in human cancer. Nevertheless, the genomic structure, the intronic primer sequences, and polymorphisms of the hMAD2 gene presented here will facilitate future studies to determine the full spectrum and frequency of the genetic events that can affect expression of the hMAD2 gene in human tumors.

Self-augmentation effect of male-specific products on sexually differentiated progesterone metabolism in adult male rat liver microsomes

It is well known that several 3-keto-4-ene steroids such as progesterone and testosterone are metabolized in a gender-specific or -predominant manner by adult rat liver microsomes. In the male, these steroids are primarily metabolized into two oxidized (16alpha-hydroxyl and 6beta-hydroxyl) products mainly by the respective, male-specific cytochrome P450 subforms, CYP2C11 and CYP3A2, while they are primarily metabolized into the 5alpha-reduced products by female-predominant 5alpha-reductase in the female. These sexually differentiated enzyme activities are largely regulated at the transcription level under endocrine control. In the present study, we show that unlabeled 16alpha-hydroxyprogesterone and 6beta-hydroxyprogesterone inhibited the 5alpha-reductive [(3)H]progesterone metabolism by adult male rat liver microsomes without significantly inhibiting the CYP2C11 and CYP3A2 activities producing themselves, whereas 3alpha-hydroxy-5alpha-pregnan-20-one and 5alpha-pregnane-3,20-dione not only stimulated the 5alpha-reductive metabolism producing themselves but also inhibited the male-specific oxidative metabolism. This finding compels us to propose a novel hypothesis that adult male rat liver microsomes may possess a self-augmentation system regulated by the male-specific products on sexually differentiated steroid metabolism, besides regulation by gene expressions of the related enzymes.

Mutation analysis of the gene encoding the human mannose 6-phosphate/insulin-like growth factor 2 receptor (M6P/IGF2R) in human cell lines resistant to growth inhibition by transforming growth factor beta(1) (TGF-beta(1))

The mannose 6-phosphate/insulin-like growth factor 2 receptor (M6P/IGF2R) is involved in activating the transforming growth factor beta(1) (TGF-beta(1)), an inhibitor of the cell proliferation, and limiting the insulin-like growth factor 2 mediated-growth stimulation. The M6P/IGF2R gene has been reported to be mutated and deleted in various cancers, and is a candidate tumor suppressor gene. We studied the genomic structure of the M6P/IGF2R gene and designed the intron primers to detect mutations in the M6P/IGF2R gene of genomic DNA samples. The M6P/IGF2R gene consists of 48 exons. The previously reported 23 mutations of the M6P/IGF2R gene in human cancers, liver, breast, and gastrointestinal tumors, are located in five exons, exon 27, 28, 31, 40, 48. Using the intron primers designed in this study, polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis, and direct sequencing, we performed an initial analysis of the complete coding sequences of the M6P/IGF2R gene in 21 human cell lines resistant to growth inhibition by TGF-beta(1). An adenine-to-guanine transition, resulting in an asparagine-to-serine amino acid substitution, was found in one lung adenocarcinoma cell line at exon 40 where the mutation has been previously reported in human cancers. This is the first report of a mutation of the M6P/IGF2R gene in lung tumor. These results indicated that the mutation in M6P/IGF2R may be involved in human lung cancinogenesis.

Novel toluene elimination system in a toluene-tolerant microorganism

In studies of Pseudomonas putida IH-2000, a toluene-tolerant microorganism, membrane vesicles (MVs) were found to be released from the outer membrane when toluene was added to the culture. These MVs were found to be composed of phospholipids, lipopolysaccharides (LPS), and very low amounts of outer membrane proteins. The MVs also contained a higher concentration of toluene molecules (0.172 +/- 0. 012 mol/mol of lipid) than that found in the cell membrane. In contrast to the wild-type strain, the toluene-sensitive mutant strain 32, which differs from the parent strain in LPS and outer membrane proteins, did not release MVs from the outer membrane. The toluene molecules adhering to the outer membrane are eliminated by the shedding of MVs, and this system appears to serve as an important part of the toluene tolerance system of IH-2000.

Somatic mutation of the hBUB1 mitotic checkpoint gene in primary lung cancer

Mutations in mitotic checkpoint genes have been detected in several human cancers, and these cancers exhibit chromosomal instability. Aneuploid stem cells seem to result from chromosomal instability and have been reported in many lung cancers. To determine whether alteration of mitotic checkpoint regulators is involved in carcinogenesis and tumor progression in primary lung cancer, we screened the genomic DNA sequence of 30 human lung cancer cell lines and 30 primary lung cancer tumors for a mutation in the hBUB1 mitotic checkpoint gene. First, we designed 26 sets of intron-based primers to amplify each of the 25 exons of the hBUB1 gene to examine the entire coding region of the hBUB1 gene. Using these primers, we performed polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis as well as direct sequencing in the mutation analysis of the hBUB1 gene. Three different nucleotide substitutions were detected in the coding region of the hBUB1 gene in some of the cancer cell lines and primary tumors as follows. The hBUB1 gene of one adenocarcinoma tumor contained a somatic missense mutation, a cytosine-to-guanine substitution in codon 51 of exon 5 that resulted in a histidine-to-aspartic acid amino acid substitution. The hBUB1 gene of three lung cancer cell lines contained a thymine-to-cytosine substitution in codon 430 of exon 12, which did not result in an amino-acid substitution. We were unable to determine whether the nucleotide substitution in exon 12 was a polymorphism or a silent mutation because matched normal tissue was not available. A polymorphism in codon 93 of exon 4, a guanine-to-thymine substitution, in hBUB1 was found in one lung cancer cell line and one primary lung tumor. This is the first report of a somatic missense mutation of a gene involved in a mitotic checkpoint in primary lung cancer. The presence of a point mutation in the hBUB1 gene is consistent with the hypothesis that alteration of mitotic checkpoint genes is involved in the development of primary lung cancers. Because the frequency of hBUB1 gene mutations was low, future studies should focus on other mechanisms of inactivation of the hBUB1 gene as well as mutation analysis of other mitotic checkpoint genes in lung cancers.

Clinicopathologic analysis of stage II-III hepatocellular carcinoma showing early massive recurrence after liver resection

BACKGROUND AND AIMS

Prognosis after hepatectomy for hepatocellular carcinoma (HCC) has been improved by progress in the evaluation of hepatic functional reserve, surgical techniques and perioperative management. However, even when curative resection is performed at a relatively early stage, a considerable number of patients develop early intrahepatic and/or extrahepatic recurrence postoperatively. This study analyzed the clinicopathologic features of HCC with early recurrence.

METHODS

We reviewed records of 513 consecutive patients who had undergone liver resection for HCC. There were 48 deaths within a year after surgery from recurrence, including 21 patients with stage II or III HCC (group I). Clinicopathologic parameters of group I patients were compared with those of 188 patients (group II) who developed recurrence following resection of stage II or III HCC and died more than 1 year after surgery.

RESULTS

On univariate analysis, age, tumor diameter (phi), alpha-fetoprotein (AFP):phi and protein induced by vitamin K absence or antagonist II (PIVKA-II):phi were significantly greater in group I than in group II. Macroscopic portal vein invasion, microscopic vascular invasion, intrahepatic metastasis, poor differentiation, pleomorphism, sarcomatous change, vascular lake, and angiographic condensed pooling were more frequently observed in group I than group II. Five independent determinants were selected by multivariate analysis: AFP:phi, histologic pleomorphism, sarcomatous change, vascular lake and angiographic condensed pooling.

CONCLUSIONS

Highly malignant HCC with extremely poor prognosis exhibits peculiar clinicopathologic characteristics, particularly histologic immaturity, and can be predicted by preoperative indicators such as markedly elevated tumor marker concentrations and condensed pooling on angiography.

Posthatching development of spinal motoneurons in the angelfish Pterophyllum scalare

We investigated the posthatching developmental sequence of spinal motoneurons innervating the axial muscles in the teleost angelfish, Pterophyllum scalare, by means of retrograde labeling with horseradish peroxidase. Two discrete types of spinal motoneurons, primary-type motoneurons and secondary motoneurons were labeled in a temporally different sequence during the course of larval development. These two types of motoneurons were morphologically distinguishable from one other. Primary-type motoneurons are generated by day 1 posthatching and do not increase in number over the observed period (to day 12 posthatching). In contrast, the secondary motoneurons increase in number through posthatching day 3. Differentiation of the spinal motoneurons appears to be nearly complete a few days before the onset of free swimming. In addition, the data suggest that the differentiation of secondary motoneurons precedes the development of the red muscle that is to be innervated by the motoneurons.

The role of oval cells in rat hepatocyte transplantation

BACKGROUND

Oval cells are liver cells capable of differentiating into either hepatocytes or biliary epithelial cells. We compared growth of hepatocytes and biliary epithelial cells between spleens transplanted with oval cell-free and oval cell-enriched rat liver cells.

METHODS

Oval cell-enriched liver cells were obtained from livers of adult rats that had undergone treatment with acetylaminofluorene and partial hepatectomy, although oval cell-free liver cells were obtained from livers of untreated rats. Hepatocyte and biliary epithelial cell growth in the spleen was evaluated by counting periodic acid-Schiff-positive cells and cytokeratin 19-positive cells respectively in sections from transplanted spleens.

RESULTS

Spleens transplanted with oval cell-free liver cells and spleens transplanted with oval cell-enriched liver cells contained similar numbers of hepatocytes after 2 weeks. Numbers of hepatocytes in spleens transplanted with oval cell-free liver cells decreased markedly at 4 and 8 weeks, then increasing slightly until 32 weeks. In spleens transplanted with oval cell-enriched liver cells, numbers of hepatocytes decreased only slightly at 4 weeks and then increased markedly. At 4, 8, 12, 16, 24, and 32 weeks, numbers of hepatocytes in spleens transplanted with oval cell-enriched liver cells respectively were 2.3, 3.5, 4.5, 6.7, 6.3, and 15.1 times hepatocyte numbers in spleens transplanted with oval cell-free liver cells. Numbers of biliary epithelial cells in spleens receiving oval cell-enriched liver cells showed changes similar to those in spleens transplanted with oval cell-free liver cells, increasing markedly at 4 weeks and then markedly and rapidly decreasing.

CONCLUSIONS

Intrasplenic transplantation of oval cell-enriched liver cells enhanced growth of hepatocytes compared with transplantation of oval cell-free liver cells; this was not true for biliary epithelial cells.

Inhibition by an angiogenesis inhibitor, TNP-470, of the growth of a human hepatoblastoma heterotransplanted into nude mice

BACKGROUND/PURPOSE

The effect of TNP-470, an angiogenesis inhibitor, on the growth of a hepatoblastoma transplanted into nude mice was examined.

METHODS

A hepatoblastoma obtained from a 3-year-old girl was serially transplanted into nude mice subcutaneously, and the transplant tumors of the seventh and eighth generations were used for experiments. Expression of various markers in the tumors was examined immunohistochemically. TNP-470 was injected subcutaneously every other day into tumor-bearing mice from 3 weeks after tumor transplantation. The proliferation of tumor cells and endothelial cells was estimated by means of the bromodeoxyuridine labeling index.

RESULTS

The original hepatoblastoma showed the histology of the epithelial type, consisting of both the fetal and embryonal subtypes and was positively stained with anti-alpha-fetoprotein (AFP), anti-cytokeratin-19 and polyclonal anticarcinoembryonic antigen antibodies, and an antihuman hepatocyte antibody (hepatocyte paraffin 1). The transplant tumors consisted of solid nests of tumor cells with numerous vascular lakes of various sizes, and showed positive staining with all antibodies that reacted positively with the original hepatoblastoma. Injections of TNP-470 at the doses of 15 mg and 30 mg/kg body weight suppressed the tumor growth and the increase in the serum level of AFP dose dependently. Injections of TNP-470 also suppressed the proliferation of tumor cells and endothelial cells in the tumors.

CONCLUSIONS

Hepatoblastomas maintained in nude mice retained the immunohistochemical characteristics of the original hepatoblastoma, and TNP-470 suppressed the growth of hepatoblastomas transplanted into nude mice. TNP-470 may be worth investigating further as to its usefulness as a therapy for hepatoblastomas.

[Mechanism of resistance to growth inhibition by transforming growth factor-beta 1 (TGF-beta 1) in primary lung cancer and new molecular targets in therapy]

Transforming Growth Factor-beta 1 (TGF-beta 1) regulates the proliferation of normal epithelial cells, and resistance to TGF-beta 1 growth inhibition is a common feature of human cancers including lung cancer. In order to understand the mechanism of resistance to growth inhibition by TGF-beta 1 and to reverse the regulation of proliferation in lung cancer, we determined the genomic structure of the genes involved in the signal transduction pathway of TGF-beta 1 and performed an initial mutation survey of the complete coding region of the genes in lung cancer and cell lines with the resistance to growth inhibition by TGF-beta 1. First, a mutation analysis of the TGF-beta type II receptor (TGF-beta RII) was performed. Point mutations of the gene were detected in several colon cancers and an adenocarcinoma of the lung in the poly-A sequence. No mutations of Smad 2, 3, 4, 5 and TGF-beta type I receptor (TGF-beta IR) genes were detected in a series of the tumors we tested, although several mutations of Smad 2 and 4 were previously reported. Frequent alterations of the p15 gene and reduced expression of p21 we already reported from our previous studies. We also determined the genomic structure of the mannose 6-phosphate/insulin-like growth factor 2 receptor (M6P/IGF2R), which is involved in activating TGF-beta 1, and performed an initial mutation survey of the complete coding sequences of the gene. A point mutation at exon 40 was found in one lung adenocarcinoma cell line. In summary, alterations in the many genes involved in the signal transduction of TGF-beta 1 were found and may mediate the loss of TGF-beta 1 responsiveness in lung cancer. The molecular targets for the regulation of the proliferation of lung cancer are thought to be p15, p21 and the transcriptional regulators.

[Microscopic polyangiitis accompanying interstitial pneumonia with aluminum lung]

A 67-year-old man who had worked as an aluminum grinder had been given a diagnosis of pneumoconiosis. Ten years later, he was admitted with fever, dyspnea on exertion, and numbness. Chest roentgenograms showed linear-reticular shadows in both lower lung fields. ELISA-based tests were positive for perinuclear anti-neutrophil cytoplasmic antibody (P-ANCA). Renal biopsy specimens disclosed crescentic glomerulonephritis and angiitis of small arteries. Our diagnosis was microscopic polyangiitis accompanying interstitial pneumonia with aluminum lung. The results of high-energy dispersion X-ray microanalysis indicated that the patient's lungs contained aluminum. His general condition improved with the administration of corticosteroid and immunosuppressive agents, and his chief symptoms disappeared.

What patients can survive disease free after complete resection for hepatocellular carcinoma?: A multivariate analysis

BACKGROUND

Although there have been extensive studies to determine risk factors affecting survival after resection for hepatocellular carcinoma (HCC), we still do not know which patients can survive disease free after curative resection. This study was undertaken to determine independent risk factors affecting the length of disease-free survival.

METHODS

171 patients, who survived disease free more than 1 year after curative resection, were divided into four groups according to the disease-free period: Group I (n = 96) for the patients with intrahepatic recurrence between 1 and 3 postoperative years, Group II(n = 27) for those between 3 and 5 years, Group III (n = 40) for those between 5 and 10 years and Group IV (n = 8) for those without recurrence within 10 years. The 37 variables (host factors, tumor factors, non-tumor liver factors, surgical factors) were compared among the four groups. Activity of hepatitis and hepatic fibrosis was scored by the Histological Activity Index (HAI). In a multivariate study, possible prognostic variables with a statistical difference in the disease-free survival rate among each category were preliminarily selected from the 37 variables and the independent variables were finally selected using a proportional hazard analysis.

RESULTS

The patients' age, indocyanine green retention rate, microscopic tumor capsular invasion and portal invasion, cell differentiation, extent of hepatectomy, aggressiveness of chronic hepatitis and inflammatory activity assessed by HAI score were significantly different among the four groups. In the multivariate analysis, the following variables were selected as the independent determinants favorable for achieving a longer disease-free period: younger age, lower indocyanine green retention rate, solitary HCC with expansive growth, no microscopic portal invasion and lower activity of co-existing hepatitis.

CONCLUSIONS

The importance of inflammatory activity in addition to aging, hepatic reserve and tumor characteristics was confirmed as a risk factor for recurrence by multivariate analysis. To achieve better disease-free survival, not only early detection but also suppression of co-existing hepatitis is necessary.