Immunolocalization of osteoclast differentiation factor in rat periodontium

The aim here was to observe the immunohistochemical localization of osteoclast differentiation factor (ODF)/receptor activator of NF kappa B ligand (RANKL) in the rat periodontium. Rat mandibles were demineralized and embedded in paraffin, and horizontal and frontal sections were prepared for immunohistochemical analysis. In horizontal sections, immunolocalization of RANKL was marked in the distal area of the periodontium of molars in which osteoclasts appeared, due to physiological tooth drift. In frontal sections, RANKL immunoreactivity was localized on spindle-shaped mesenchymal cells around blood vessels near the bone surface in the periodontium. In addition, immunoreaction for RANKL was detected on structures that appeared to be elongated cell processes near blood vessels in frontal sections. Immunohistochemical examination for the general antigen of nerve-specific protein suggested a similarity between these structures and nerve fibres.

Plasma digoxin concentration in dogs with mitral regurgitation

Fifteen and eight mature beagles, without (normal group) and with experimental mitral regurgitation (MR group), respectively, were given 0.02 mg/kg/day digoxin powder for 10 days orally. The optimum time for sample collection after administration of digoxin was observed to be 8-18 hr and 10-22 hr in the normal and MR groups, respectively. In both groups, a stable concentration was reached after 3-5 days of treatment. No differences in plasma level were observed between sexes. The optimum concentration of digoxin was attained at an earlier stage than has been previously reported for both dogs and humans.

Detachable coils for occlusion of patent ductus arteriosus in 2 dogs

OBJECTIVE

To describe the use of a detachable coil for transcatheter closure (TCC) of patent ductus arteriosus (PDA) in 2 dogs.

STUDY DESIGN

Clinical study.

ANIMALS

Two female Pembroke Welsh Corgi dogs with PDA.

METHODS

Using fluoroscopic guidance, an 8-mm-diameter coil stent with 5 loops (detachable coils for PDA closure) was inserted via catheterization of the femoral artery. The catheter was passed through the PDA into the pulmonary artery. The coil was withdrawn so that 1.5 loops remained on the pulmonary side of the orifice of the ductus. The rest of the loops were pushed out from the catheter into the ductus. After confirming the correct placement of the coil and the effectiveness of the occlusion, the delivery wire was detached from the coil.

RESULTS

Insertion of the coil was easily performed, even without previous experience. Immediate and marked decrease of the cardiac murmur was auscultated. Only slight residual flow was detected by angiography conducted 3 months' postoperatively. The dogs experienced quick and uneventful recovery after coil placement and required minimal postoperative care. Follow-up evaluation of the dogs showed no functional clinical signs of PDA, and no cardiac abnormalities were detected on electrocardiographic, phonocardiographic, and echocardiographic examination. In dog 1, the residual flow had disappeared on the color-flow Doppler echocardiographic examination at 18 months' postoperatively.

CONCLUSION

TCC using a detachable coil was easy, safe, and effective in 2 dogs with PDA. The minimal residual shunting observed only by echocardiography seemed hemodynamically insignificant.

CLINICAL RELEVANCE

This method can be used as an alternative to traditional surgical methods.

[A case of ovarian cancer with metastatic tumor in the liver with paclitaxel and carboplatin systemic chemotherapy was very effective]

An 82-year-old woman was admitted to the Dept. of Obstetrics and Gynecology, Yamanashi Medical University to try to identify the origin of a liver metastatic tumor. CT examination revealed a small tumor located adjacent to the uterine cervix in a cul-de-sac. With biopsy using MR, it was clearly shown histologically that the origin of the tumor was the ovary. Systemic chemotherapy with paclitaxel and carboplatin was selected as the most reasonable treatment for this case because of the patient's age. After 6 courses of this chemotherapy, the tumor in the cul-de-sac disappeared and the tumor in the liver decreased markedly. Furthermore, no severe side effects were seen during this treatment. This result indicated that systemic chemotherapy with paclitaxel and carboplatin is effective and safe in cases of advanced ovarian cancer.

Is milk responsible for male reproductive disorders?

The role of environmental compounds with estrogenic activity in the development of male reproductive disorders has been a source of great concern. Among the routes of human exposure to estrogens, we are particularly concerned about cows' milk, which contains considerable amounts of estrogens. The major sources of animal-derived estrogens in the human diet are milk and dairy products, which account for 60-70% of the estrogens consumed. Humans consume milk obtained from heifers in the latter half of pregnancy, when the estrogen levels in cows are markedly elevated. The milk that we now consume may be quite unlike that consumed 100 years ago. Modern genetically-improved dairy cows, such as the Holstein, are usually fed a combination of grass and concentrates (grain/protein mixes and various by-products), allowing them to lactate during the latter half of pregnancy, even at 220 days of gestation. We hypothesize that milk is responsible, at least in part, for some male reproductive disorders.

Evaluation of tube compensation in the Bennett 840 ventilator--a new ventilatory mode to support spontaneous breathing

Respiratory care patients frequently require intubation with an endotracheal tube (ETT). Unfortunately, the ETT introduces a pressure drop (deltaPETT) that depends on the respiratory flow rate, thus increasing the work of breathing (WOB). Pressure support ventilation (PSV) cannot adequately compensate for this added WOB, because the degree of inspiratory assistance by PSV is fixed. Therefore, a technique called tube compensation (TC) has been developed to address deltaPETT. We examined the performance of TC and compared it with PSV of 5 cm H2O. The experimental system was constructed from a simulator, a test-lung, flow sensors, and a Bennett 840, and the respiratory parameters were studied. ETTs with IDs 6.5 and 8.0 mm were used. The quadratic approximation obtained for deltaPETT in the 6.5-mm ETT was 2.316 x flow + 7.910 x flow2, while that for the 8.0-mm ETT was 1.881 x flow + 3.353 x flow2. The maximum inspiratory flow (MIF) increased significantly with increasing TC, but tidal volume and inspiratory time did not show marked changes. The MIF for TC of 100% was larger than that for PSV of 5 cm H2O, when the 6.5-mm ID was used, but there was no significant difference between these modes when an ID of 8.0 mm was used. For both the 6.5 and 8.0-mm IDs, the PV loop corresponding to 100% TC was larger than that for PSV of 5 cm H2O. TC only compensated for the WOB caused by the ETT, whereas PSV compensated for the WOB caused by the ETT and the demand valve system. In clinical use, the differences between TC and PSV will demand attention.

[Rheumatic pain]

RA is a chronic inflammatory arthropathy that characterized by joint destruction with invasive proliferation of synovial cells in articular cartilage. Inflammatory cytokines like TNF-alpha, IL-1 and IL-6 are overproduced and play an important role in the process. In order to relief patient's chronic pain and to prevent of joint destruction, NSAIDs, steroids and DMARDs are common. Recently, anti-cytokine therapy develop and neutralizing antibody to TNF-alpha (infliximab) and TNF-alpha receptor/IgG fusion protein(etanercept) are already used in U.S.A. and in Europe. In Japan, these medicines are now on clinical trial and will be available in a few years. Other anti-cytokine therapy like IL-1 receptor antagonist and anti-IL-6 receptor antibody is also on clinical trial.

The novel untranslated exon "exon 0T" encoded between the exon 0 and exon 1 of the rat estrogen receptor alpha (ER alpha) gene

We have recently isolated two untranslated first exons, exon 0N and exon 0S, of rat estrogen receptor alpha (ER alpha) gene from the liver by use of 5'-rapid amplification of the cDNA ends (5'-RACE) method. In this communication, we further analyzed the 5'-untranslated region (UTR) of the ER alpha mRNA in rat anterior hypophysis in order to investigate the existence of the other 5'-untranslated exon(s) of rat ER alpha gene. Total RNA from the anterior hypophysis of 8-week-old female Wistar strain male rats was subjected to 5'-RACE with antisense primers located in exon 1 of the rat ER alpha gene and one of the positive clones (clone 35) was sequenced. The nucleotide sequence of clone 35 revealed the insertion of a previously unidentified exon (which we termed "exon 0T") between exon 0 (the first reported 5'-UTR form of rat ER alpha mRNA) and exon 1 of rat ER alpha mRNA. Analysis of rat genomic DNA indicated that exon 0T was located between exon 0 and exon 1 of rat ER alpha gene. We further investigated the distribution of ER alpha mRNA containing exon 0T in several brain regions and various peripheral tissues of 8-week-old male and female Wistar strain rats by use of reverse transcription-polymerase chain reaction (RT-PCR). The distribution of the ER alpha mRNA (0T-1) was essentially similar to that of ER alpha mRNA in which exon 0 was spliced onto exon 1 reported previously. These results indicate that (1) exon 0T is a novel untranslated exon of rat ER alpha gene which is located between exon 0 and exon 1 on rat genomic DNA, (2) exon 0T is inserted between exon 0 and exon 1 of ER alpha mRNA by alternative splicing, and (3) this alternative splicing may occur in tissues where the transcription of ER alpha gene is initiated from exon 0.

Targeted disruption of cadherin-11 leads to a reduction in bone density in calvaria and long bone metaphyses

The migration and adhesion of osteoblasts requires several classical cadherins. Cadherin-11, one of the classical cadherins, was expressed in mouse osteoblasts in skull bone and femur, revealed by immunohistochemistry. To elucidate the function of cadherin-11 in osteoblastogenesis, cadherin-11 null mutant mice were investigated. Although apparently normal at birth, Alizarin red staining of null mutant mice showed a reduced calcified area at the frontal suture that caused a round-shaped calvaria with increasing animal age to 3 months. Consequently, there was a reduction in bone density at the femoral metaphyses and the diploë of calvaria in null mutant mice. In the in vitro culture of newborn calvarial cells, the calcified area of mutant cells was smaller than those derived from wild-type littermates. These results show that absence of cadherin-11 leads to reduced bone density in some parts of skeletons including calvaria and long bone metaphyses, and thus suggest that cadherin-11 plays roles in the regulation of osteoblast differentiation and in the mineralization of the osteoid matrix.

The multiple untranslated first exons system of the human estrogen receptor beta (ER beta) gene

In order to investigate the regulatory mechanism of the expression of the human estrogen receptor beta (ER beta) gene, we have analyzed the structure of the 5'-untranslated region of the ER beta mRNA in the normal uterine endometrium and liver using the 5'-rapid amplification of the cDNA ends method. The sequence analysis revealed the presence of the two isoforms of the ER beta mRNA containing the distinct 5'-untranslated regions. The genomic analysis revealed that the two isoforms of the message originated from the two distinct untranslated first exons, termed the exon 0K and exon 0N, which were spliced to the exon 1. We termed the two isoforms of the message the ER beta mRNA (0K-1) and ER beta mRNA (0N-1). We further analyzed the distribution of the ER beta mRNA (0K-1) and ER beta mRNA (0N-1) in the ejaculated spermatozoa, liver, uterine endometrium and myometrium, and peripheral leukocytes using the reverse transcription-polymerase chain reaction. The distributions of the two mRNA isoforms were different from each other. From these results, it is indicated for the first time that the expression of the human estrogen receptor beta (ER beta) gene is regulated, at least in part, by the multiple untranslated first exons and promoters system.

Differential localization and colocalization of two neuron-types of sodium-dependent inorganic phosphate cotransporters in rat forebrain

We studied by immunohistochemistry the distribution of differentiation-associated sodium-dependent inorganic phosphate (Pi) cotransporter (DNPI) in the rat forebrain, in comparison with brain-specific cotransporter (BNPI). DNPI-staining was principally seen in axonal synaptic terminals which showed a widespread but discrete pattern of distribution different from that of the BNPI-staining. In the diencephalon, marked DNPI-staining was seen in the dorsal lateral geniculate, medial geniculate, ventral posterolateral, ventral posteromedial, anterior, and reticular thalamic nuclei without the colocalization with BNPI-staining. DNPI-staining showed a strong mosaical pattern and overlapped well the BNPI-staining in the medial habenular nucleus. DNPI-staining was moderate over the hypothalamus and notably localized in neurosecretory terminals containing corticotropin-releasing hormone in the median eminence. In contrast, the BNPI-staining was region-related and strong in the ventromedial and mammillary nuclei. In the telencephalon, laminar DNPI-staining was seen over the neocortex, corresponding to the thalamocortical termination, and also found in the retrosplenial cortex and the striatum, with the highest intensity in the accumbens nucleus shell. The present results suggest that DNPI serves as a dominant Pi transport system in synaptic terminals of diencephalic neurons including thalamocortical and thalamostriatal pathways as well as the hypothalamic neuroendocrine system in the rat forebrain.

Partial bladder resection in a bitch with urinary retention following surgical excision of a vaginal leiomyoma

Ovariohysterectomy and surgical excision of a vaginal leiomyoma were performed in a bitch exhibiting continuous bleeding from the vulva. Following excision of the tumour, urine retention and urinary incontinence developed. Treatment using drugs and an indwelling catheter was unsuccessful in correcting the disorders and chronic cystitis developed after long-standing urine stagnation in the bladder. The authors resorted to undertaking partial cystectomy in order to correct the condition, which resulted in reduced urine retention and improved micturition.

Supplemental embolization coil implantation for closure of patent ductus arteriosus in a beagle dog

Embolization coil for the occlusion of patent ductus arteriosus (PDA) was inserted in a beagle dog diagnosed as PDA with systolic murmur. Residual shunt was observed three months postoperatively and then supplemental coil was inserted. In the past only one coil was required for the closure of PDA in our cases with good post-operative results. In this case, however, the largest coil presently available (8 mm in diameter with 5 loops) was inadequate to make sufficient closure within 3 months postoperatively and supplemental coil insertion was necessary to produce a successful occlusion.

Differences in respiratory parameters during continuous positive airway pressure and pressure support ventilation in infants and children

The extubation criteria of pressure support ventilation (PSV) in infants and children were not yet established. We studied the differences in respiratory parameters during continuous positive airway pressure (CPAP) using a constant flow type ventilator and PSV using a demand valve type ventilator. Nineteen children (1.9+/-2.9 years old) who were ready to extubate were studied. All patients had recovered from their respiratory failure and had finished the weaning process of the ventilatory support. They were scheduled for extubation on the next day when their ventilatory mode had attained to a PSV of 3 cmH2O with a positive end-expiratory pressure (PEEP) of 3 cmH2O. On the extubation day, tidal volume (TV) and respiratory frequency (RR) were measured with a respiratory monitor at two modes (CPAP of 3 cmH2O and PSV), and the duty ratio (DR) and mean inspiratory flow (MF) were calculated. The sequence of the ventilatory mode was random. No case required reintubation. TV was 61.6+/-54.9 during CPAP and 67.7+/-61.4 ml during PSV, and RR was 38.5+/-10.6 and 37.1+/-8.8 beats/min., respectively. DR was 0.382+/-0.067 and 0.359+/-0.085, and MF was 96.6+/-78.3 and 101.0+/-69.0 ml/sec., respectively. The measured parameters and calculated values showed no significant difference between CPAP and PSV. It was found that the respiratory parameters were almost the same with CPAP and PSV immediately before the extubation, and the previous extubation criteria of CPAP can be used.

Curing properties of furfuryl alcohol condensate with carbonaceous fine particles under ultrasonication

Ultrasonic treatment (sonication) was carried out through the curing process of furan resin by using an ultrasonic homogenizer at the frequency of 20 kHz and the various intensities (0-90 W). Various carbonaceous fine particles were added to furan resin to investigate the change of polymerization degree. The curing rate of furan resin was accelerated by sonication, which increased the polymerization degree with an increase in ultrasound intensity. The increase of curing rate was also observed by small additions of carbonaceous fine particles. In this case, the curing rate was increased with an increase in the specific surface area on additives.

Histopathological characterization of melorheostosis

Melorheostotic bone was examined histopathologically. In the severely affected areas, an abundance of osteoid and increased angiogenesis was observed. Increased osteoid without mineralization indicated the overproduction of bone matrix. Bone resorption also appeared to increase because osteoclasts were numerous in melorheostotic bone, thus suggesting a high rate of bone turnover. In addition, transforming growth factor-beta was immunolocalized in the periosteal fibroblasts, mesenchymal cells surrounding vessels, endothelial cells, and osteoblasts, while basic fibroblast growth factor was found in endothelial cells and mast cells near vessels. These cytokines may have some association with the exuberant bone matrix production and angiogenesis in melorheostosis.

The novel isoform of the progesterone receptor cDNA in the human testis and detection of its mRNA in the human uterine endometrium

A novel isoform (termed isoform S) of the progesterone receptor (PR) cDNA (PR isoform S cDNA) which consists of a previously unidentified 5' sequence and exons 4-8 of the intracellular PR gene has been cloned from the human testicular cDNA library. The 5' sequence of the message was confirmed to be derived from a novel exon (termed exon S) by genomic cloning. The expression level of the PR isoform S mRNA was higher in the spermatozoon than in the uterine endometrium with a lower expression level of the PR isoforms B and A mRNAs in the spermatozoon than in the endometrium. These results implied that the PR isoform S which was possibly translated from the PR isoform S mRNA in the spermatozoon might be related to the cell surface membrane PR. Moreover, the PR isoform S in the uterine endometrium might play some physiological and/or pathogenic roles.

Antioxidative effect of fluvastatin, an inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase, on peroxidation of phospholipid liposomes

The antioxidative effect of fluvastatin sodium (fluvastatin), a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, on lipid peroxidation of phosphatidylcholine (PC) liposomes was investigated in various peroxidizing systems. Fluvastatin markedly inhibited the formation of thiobarbituric acid reactive substances in iron (II)-supported peroxidation of liposomes (IC50 = 1.2 x 10(-5) M). The order of magnitude of inhibition of each drug on the peroxidation was: butylated hydroxytoluene > fluvastatin > or = probucol >> pravastatin. Moreover, concentrations of fluvastatin ranging from 1 x 10(-6) to 1 x 10(-4) M inhibited peroxyl radical-mediated peroxidation of liposomes induced by water-soluble and lipid-soluble radical generators, 2,2'-azobis (2-amidinopropane) dihydro-chloride and 2,2'-azobis (2,4-dimethylvaleronitrile), respectively. However, pravastatin showed no effect against peroxyl radical-mediated peroxidation. These results indicate that fluvastatin acted non-enzymatically as an effective inhibitor against lipid peroxidation of PC liposomes and that the antioxidative effects of fluvastatin may be due to the scavenging action of fluvastatin on liposomal lipid peroxidation induced by peroxyl radicals generated in the aqueous and lipid phases.

Rapid detection of chromosome aneuploidies by prenatal interphase FISH (fluorescence in situ hybridization) and its clinical utility in Japan

OBJECTIVE

The purpose of this study was to assess the accuracy, informative rate, detection rate, and clinical utility of prenatal interphase fluorescence in situ hybridization (FISH) analysis of amniotic fluid samples from Japanese women.

METHODS

Amniotic fluid specimens from 2,639 Japanese women were received for prenatal interphase FISH and chromosome analysis. A questionnaire was designed to evaluate FISH clinical utility by collaboration sites.

RESULTS

Based on 2,319 tested samples, the accuracy (100%), informative (94%), and detection (87.6%) rates were all high. The accuracy (100%), informative (90.2%), and detection (90.0%) rates were also remarkable in third-trimester pregnancies. We perceive significant advantages from this test regarding medical management and patient satisfaction.

CONCLUSIONS

This novel report shows that in Japan prenatal interphase FISH testing is highly informative and accurate, not only in second-trimester pregnancies but also in third-trimester pregnancies. This test provides advantages to both physicians and patients, provided that its capabilities and limitations are understood.

[A multicenter cross-sectional study on the Health Related Quality of Life of patients with rheumatoid arthritis using a revised Japanese version of the Arthritis Impact Measurement Scales Version 2 (AIMS 2), focusing on physical disability and its associative factors]

OBJECTIVE

A multicenter cross-sectional survey was conducted to study the current status of Health Related Quality of Life (HRQL) of Japanese patients with rheumatoid arthritis using a revised Japanese version of the AIMS 2, to investigate the association among the self-report physical disability scores and demographic, socioeconomic, and clinical variables in these patients.

METHODS

A Japanese version of the AIMS 2 was administered to the randomly chosen 1614 patients with classical and definite rheumatoid arthritis attending arthritis clinics at eleven hospitals across the country. Self-report functional disability scores (FDSs) were calculated, by which patients were classified into five groups with graded levels of disability. Univariate correlations were examined between FDSs and the scores of the other four components of AIMS-HRQL, disease duration, age, medical costs, and physical and laboratory measures. Analysis of variance was performed to test for among level differences of these variables in each group of patients. Mean values and standard deviations of FDSs were calculated and analysis of variance was used to test for among level differences of the following factors: demographic, socio-economic, clinical measures, and treatment status.

RESULTS

Among four scales composing the AIMS 2-HRQL, work disability scores were most strongly correlated with FDSs, followed by the scores of pain, affection and social interaction. The more severely disabled group proved to have weaker grip strength, higher joint count, longer disease duration, higher ESR and blood level of CRP, and lower level of Hb. Patients with more disabilities proved to be older, pay more medical costs, have longer duration of morning stiffness, and higher level of RF. Patients with more advanced Steinbrocker's functional class, doctor's global assessment, Steinbrocker's anatomical stage, higher daily dose of prednisolone intake, lower level of annual income and formal education, and patients taking more kinds of NSAIDs proved to be more severely disabled. Separate, single (never married, widowed), and divorced patients proved to be more severely disabled compared with married ones. Overall, females were more disabled than males.

CONCLUSION

Physical disability is associated with the other important aspects of QOL, clinical signs and symptoms, and socio-economic conditions in RA patients. Prevention and management of physical disability should be seriously planned in consideration of the changes in these conditions in RA patients.

Localizational alterations of calcium, phosphorus, and calcification-related organics such as proteoglycans and alkaline phosphatase during bone calcification

To further approach the mechanisms of bone calcification, embryonic rat calvariae were observed at electron microscopic level by the means of fine structures and various cytochemical localizations, including nonspecific proteoglycan (PG) stained by cuprolinic blue (CB), decorin, chondroitin sulfate, hyaluronan, and alkaline phosphatase (ALP), as well as the elemental mapping of calcium (Ca) and phosphorus (P) by energy-filtering transmission electron microscopy (EFTEM). In the calvariae, calcification advanced as the distance from osteoblasts increased. Closer to the osteoblasts, the osteoid was marked by an abundance of CB-positive PGs around collagen fibrils. After crystallization within matrix vesicles, calcified nodules formed and expanded, creating a coherent calcified matrix. The sizes of CB-positive PG-like structures diminished as calcification proceeded. Although small CB-positive structures were accumulated in early stage-calcified nodules, they were localized along the periphery of larger calcified nodules. Cytochemical tests for decorin, chondroitin sulfate, and hyaluronan determined their presence in the areas around collagen fibrils of the osteoid, as well as in and around calcified nodules, whereas ALP was found in the matrix vesicles, as well as in and around the calcified nodules. Ca tended to localize at the PG sites, while P often mapped to the collagen fibril structures, in the uncalcified matrix. In contrast, Ca/P colocalization was visible in and around the calcified nodules, where ALP and smaller CB-positive structures were observed. The difference in the localization patterns of Ca and P in uncalcified areas may limit the local [Ca2+][PO4(3-)] product, leading to the general inhibition of hydroxyapatite crystallization. The downsizing of CB-positive structures suggested enzymatic fragmentation of PGs. Such structural alterations would contribute to the preservation and transport of calcium. ALP possesses the ability to boost local phosphate anion concentration. Therefore, structurally altered PGs and ALP may cooperate in Ca/P colocalization, thus promoting bone calcification.

Introduction of antisense CD44S CDNA down-regulates expression of overall CD44 isoforms and inhibits tumor growth and metastasis in highly metastatic colon carcinoma cells

We created antisense CD44 transfectants using LS174T, a colon adenocarcinoma cell line and assessed the effects of overall CD44 down-regulation on colorectal tumor growth and metastasis. The expression of antisense CD44s (the standard form of CD44) cDNA markedly inhibited the overall expression of CD44 variants. In vitro studies showed a significantly reduced ability of the stable antisense transfectants (LS174TAS1 and LS174TAS2) to bind hyaluronate and osteopontin, ligands for CD44. These cells developed tumors more slowly than controls (parental LS174T and mock transfectants) when the cells were subcutaneously injected into SCID mice. However, in vitro proliferation assays demonstrated no significant difference between the antisense transfectants and the controls on a hyaluronate-coated surface, suggesting the participation of ligands other than hyaluronate in tumor growth in vivo. Intrasplenic injection of parental LS174T cells produced colonies in the liver in 10 of 11 mice, whereas mice injected with the antisense transfectants were completely free of metastasis. In peritoneal dissemination, the weight of nodules and amount of ascites were significantly reduced in LS174TAS1 and AS2 compared with the controls. In vitro adhesion assays between the transfectants or controls and human peritoneal mesothelial cells revealed that the binding of LS174T cells to mesothelial cells was partly mediated by CD44-hyaluronate interaction. These data suggest that CD44-hyaluronate interaction plays a crucial role in peritoneal dissemination in colorectal carcinoma. The results of our study demonstrate the possible application of antisense CD44s to the treatment of colorectal carcinoma.

Introduction of antisense CD44S CDNA down-regulates expression of overall CD44 isoforms and inhibits tumor growth and metastasis in highly metastatic colon carcinoma cells

We created antisense CD44 transfectants using LS174T, a colon adenocarcinoma cell line and assessed the effects of overall CD44 down-regulation on colorectal tumor growth and metastasis. The expression of antisense CD44s (the standard form of CD44) cDNA markedly inhibited the overall expression of CD44 variants. In vitro studies showed a significantly reduced ability of the stable antisense transfectants (LS174TAS1 and LS174TAS2) to bind hyaluronate and osteopontin, ligands for CD44. These cells developed tumors more slowly than controls (parental LS174T and mock transfectants) when the cells were subcutaneously injected into SCID mice. However, in vitro proliferation assays demonstrated no significant difference between the antisense transfectants and the controls on a hyaluronate-coated surface, suggesting the participation of ligands other than hyaluronate in tumor growth in vivo. Intrasplenic injection of parental LS174T cells produced colonies in the liver in 10 of 11 mice, whereas mice injected with the antisense transfectants were completely free of metastasis. In peritoneal dissemination, the weight of nodules and amount of ascites were significantly reduced in LS174TAS1 and AS2 compared with the controls. In vitro adhesion assays between the transfectants or controls and human peritoneal mesothelial cells revealed that the binding of LS174T cells to mesothelial cells was partly mediated by CD44-hyaluronate interaction. These data suggest that CD44-hyaluronate interaction plays a crucial role in peritoneal dissemination in colorectal carcinoma. The results of our study demonstrate the possible application of antisense CD44s to the treatment of colorectal carcinoma.

Organic components of crystal sheaths in bones

Crystals in bones are enveloped within organic crystal sheaths of 5-10 nm widths. In order to analyse their components, we investigated the immunolocalizations of chondroitin 4- and 6-sulphate, keratan sulphate, bone sialoprotein and osteopontin. All of these, except chondroitin 6-sulphate, were found in bone matrix. Although the localizations of chondroitin 4-sulphate and keratan sulphate tended to focus within calcified nodules, bone sialoprotein and osteopontin were widely distributed in the area, being linearly arranged along electron-dense structures corresponding to crystal sheaths. These two proteins possess the ability to affect nucleation or elongation of hydroxyapatite, positively or negatively, in vitro. Our results suggested that bone sialoprotein and osteopontin may combine to form the crystal sheaths which are thought to control crystal formation and growth, using the seemingly opposite functions of bone sialoprotein and osteopontin.