Overexpression of p53 and rare genetic mutation in mesenchymal chondrosarcoma

Mesenchymal chondrosarcoma is extremely rare and accounts for less than 2% of all chondrosarcomas. The pathogenesis and the molecular genetic events which contribute to the development of mesenchymal chondrosarcoma are not well elucidated, due in part to the lack of sufficient tumor tissue available. To characterize the involvement of the p53 gene abnormality in this disease, we analyzed expression and sequence alteration of p53 by immunohistochemical analysis of the protein expression and quantitative DNA/PCR and PCR-SSCP assays of the gene in 33 paraffin-embedded tissue specimens. Immunohistochemical analysis demonstrated that 19 (61.3%) of 31 had nuclear overexpression of p53 while 7 (22.6%) showed cytoplasmic expression. The remaining 5 (16.1%) were negative for p53 staining. The nuclear positivity of p53 was observed within a range of 22-64% (mean 37.3%) of tumor cells and showed a positive staining in mesenchymal components as well as chondroid components. Quantitative DNA/PCR analysis revealed that 6 (18.2%) of the 33 specimens carried significantly reduced or undetectably low levels of p53 indicating the genomic deletion of the gene in these tumors. In contrast, however, DNA/PCR-SSCP analysis failed to detect any types of mutations resulting in amino acid substitution within exons 5-9 regions of the gene. Taken together, our data suggests that genetic alteration of p53 is a relatively rare event in mesenchymal chondrosarcomas but substantial fraction of this type of tumors carries abnormal overexpression of p53, which might result from as yet unidentified epigenetic mechanism(s).

Effect of a new variety of Apis mellifera propolis on mutans Streptococci

The effects of a new variety of propolis, from Northeastern Brazil (BA), on growth of mutans streptococci, cell adherence, and water-insoluble glucan (WIG) synthesis were evaluated. Propolis from Southeastern (MG) and Southern (RS) Brazil were also tested as an extension of our previous work. Ethanolic extracts of propolis (EEP) were prepared and analyzed by reversed-phase HPLC. For the antibacterial activity assays, minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) of EEPs against Streptococcus mutans, S. sobrinus, and S. cricetus were determined. Cell adherence of S. mutans and S. sobrinus to a glass surface was measured spectrophotometrically at 550 nm. WIG synthesized from sucrose by glucosyltransferase (Gtf) was extracted and quantified by the phenol-sulfuric method. The HPLC profile of the new variety of propolis was entirely different from Southeastern and Southern propolis. Neither flavonoid aglycones nor p-coumaric acid were detected in EEP BA. All EEPs demonstrated biological activities against mutans streptococci; EEP BA showed the highest potency in all in vitro parameters evaluated in this study. The ranges of MIC values were 50 (EEP BA)-400 microg/ml (MG), for S. mutans; and 25 (BA)-400 microg/ml (MG), for S. sobrinus and S. cricetus. The bactericidal concentration of EEPs was four to eight times the MIC values. The adherence of S. mutans and S. sobrinus cells and WIG synthesis were markedly inhibited by EEPs, demonstrating significant inhibition at all concentrations compared with the control (80% ethanol) (p<0.05). EEP BA showed 80% inhibition of cell adherence and WIG synthesis at concentrations as low as 12.5 and 7.8 microg/ml, respectively. The results show that the new variety of propolis was exceptionally effective in all in vitro parameters tested against mutans streptococci; biological effects of propolis are likely not to be due solely to flavonoids and (hydroxy)cinnamic acid derivatives.

Effects of Apis mellifera propolis on the activities of streptococcal glucosyltransferases in solution and adsorbed onto saliva-coated hydroxyapatite

Propolis, a resinous hive product collected by Apis mellifera bees, has been used for thousands of years in folk medicine. Ethanolic extracts of propolis (EEP) have been shown to inhibit the activity of a mixture of crude glucosyltransferase (Gtf) enzymes in solution. These enzymes synthesize glucans from sucrose, which are important for the formation of pathogenic dental plaque. In the present study, the effects of propolis from two different regions of Brazil on the activity of separate, purified Gtf enzymes in solution and on the surface of saliva-coated hydroxyapatite (sHA) beads were evaluated. The EEP from Minas Gerais (MG; Southeastern Brazil) and Rio Grande do Sul (RS; Southern Brazil) were tested for their ability to inhibit the enzymes GtfB (synthesis of insoluble glucan), GtfC (insoluble/soluble glucan) and GtfD (soluble glucan). The effects of propolis on Gtf from Streptococcus sanguis (soluble glucan synthesis) was also explored. The EEP from both regions effectively inhibited the activity of all Gtfs in solution (75-95%) and on the surface of sHA beads (45-95%) at concentrations between 0.75 and 3.0 mg of propolis/ml. However, the two samples of propolis showed different levels of inhibition on each of the enzymes tested. In general, EEP RS demonstrated a significantly higher inhibitory activity on GtfB and C activities (both solution and surface assays) than EEP MG at concentrations between 0.047 and 0.187 mg/ml (p<0.05). EEP MG, on the other hand, exhibited a greater inhibitory effect on the activities of surface GtfD (at 0.375, 0.75 and 1.5 mg/ml) and S. sanguis Gtf (at 1.5 and 3.0 mg/ml; p<0.05). These data indicate that EEP is a potent inhibitor of Gtf enzymes in solution and adsorbed on an experimental pellicle; however, its effect on Gtf activity is variable depending on the geographical origin of the propolis samples. There is a need to identify the active compounds of propolis.

Seroprevalence of toxoplasmosis in the residents of Cheju island, Korea

This study was performed to evaluate the epidemiological status of toxoplasmosis among the residents of Cheju island. The sera of local students from 18 high schools (boys 2110, girls 2460) and those of adults (474 admitted to Cheju Chungang General Hospital) were collected and checked for the IgG antibody titers against Toxoplasma gondii. Serum samples collected from both the students and adults showed sero-positive rate of 5.5% and 12.9%, respectively. Although the rates were not significantly different between the sexes (5.4% for the boys and 5.5% for the girls attending school), the geographical difference showed a significant difference between the urban (4.6-6.9%) and rural areas (5.6-8.8%) (p < 0.05). Based on the high positive rates, it should be necessary to control toxoplasmosis in Cheju island.

Persistent endemicity of Gymnophalloides seoi infection in a southwestern coastal village of Korea with special reference to its egg laying capacity in the human host

Follow-up studies have been conducted every three years on the endemicity of Gymnophalloides seoi infection in a small coastal village of Chollanam-do (Province), Korea, since it was first known as an endemic area in 1994. Special attention was given to its egg laying capacity in the human host. In fecal examinations, the overall helminth egg and/or cyst positive rate was 78.7% (74/94) in 1997 and 76.6% (82/107) in 2000. Among them G. seoi eggs showed the highest rate; 71.3% (67/94) in 1997 and 72.0% (77/107) in 2000. The average number of eggs per gram of feces (EPG) was 1,015 in 1997, while a reduced rate of 353 was observed in 2000. In 1997, total of 320,677 adult flukes of G. seoi (av. 10,344/person, 94-69,125 in range) were collected from the diarrheic stools of 31 treated patients. The EPG/worm obtained from 21 cases ranged from 0.04 to 0.77 (av. 0.23), suggesting density-dependent constraints on the worm fecundity. The relationship between the worm burden (X) and EPG/worm (Y) can be expressed as Y = 0.42.e-1.2 chi (r = 0.49). The results showed that G. seoi infection is persistently endemic in this village.

Islet cell hyperplasia of the pancreas presenting as hyperinsulinemic hypoglycemia in an adult

A 72-year-old man who had suffered several episodes of syncope was diagnosed as having hyperinsulinemic hypoglycemia. Although imaging studies and percutaneous transhepatic portal venous sampling did not reveal the existence of any tumors in the pancreas, distal pancreatectomy was performed because the possibility of a small pancreatic endocrine tumor could not be completely rejected. External examination of the surgically removed pancreas did not reveal any tumors. Microscopically, the pancreas exhibited diffuse islet cell hyperplasia without nesidioblastosis. The patient remains euglycemic and has tolerated 24-hour fasting without any medication for a period of 10 months after the operation.

3'UTR polymorphisms in the NRAMP1 gene are associated with susceptibility to tuberculosis in Koreans

SETTING

Korea University and the Korean Institute of Tuberculosis, Seoul, Korea.

OBJECTIVE

To determine whether polymorphisms in the 3' untranslated region (UTR) of the NRAMP1 gene are associated with susceptibility to tuberculosis in Koreans.

DESIGN

A case-control study design was used to compare the frequency of 3'UTR of NRAMP1 among 192 tuberculosis patients and 192 healthy individuals. All of the samples were diagnosed by X-ray, smear and culture tests between 1998 and 1999 in the Cross of Lorraine Clinic at the Korean Institute of Tuberculosis.

RESULTS

A significant association was found between the Korean tuberculosis patients and polymorphisms in the 3'UTR of the NRAMP1 gene (odds ratio [OR] 1.845; 95% confidence interval [CI] 1.097-3.104; chi2 = 5.424; P = 0.020).

CONCLUSION

This study showed that genetic variations in the human NRAMP1 gene are associated with susceptibility to smear-positive tuberculosis in Korean patients. The 3'UTR variant allele associated with susceptibility to tuberculosis is very uncommon in Caucasians, but is present in Koreans and West Africans. These observations may explain in part why African Americans and Koreans have greater susceptibility to tuberculosis than Caucasians.

Cdk7- and Cdc25A-independent dephosphorylation of Cdk2 during phorbol ester-mediated cell cycle arrest in U937 cells

The molecular mechanism underlying protein kinase C (PKC)-mediated cell cycle arrest is poorly understood. We undertook to characterize phorbol ester-activated PKC-mediated cell cycle arrest. Treatment with phorbol ester inhibited cell growth of human histiocytic lymphoma U937 cells with 83% of the cells arrested in G1 phase. Reduced activity of cdk2 correlated with cdk2 dephosphorylation and accumulation of cdk2 inhibitor p21Waf in phorbol ester-treated cells. Dephosphorylation of cdk2 was not associated with cdk7 and cdc25A activity in phorbol ester-treated cells. Protein phosphatase inhibitor assays suggest that the dephosphorylation of cdk2 results in the activation of a specific protein tyrosine phosphatase. Thus, dephosphorylation of cdk2 as well as accumulation of cdk2 inhibitor is likely to contribute to the G1 phase arrest in phorbol ester-treated in U937 cells.

Effectiveness of food fortification in the United States: the case of pellagra

OBJECTIVES

We evaluated the possible role of niacin fortification of the US food supply and other concurrent influences in eliminating the nutritional deficiency disease pellagra.

METHODS

We traced chronological changes in pellagra mortality and morbidity and compared them with the development of federal regulations, state laws, and other national activities pertaining to the fortification of cereal-grain products with niacin and other B vitamins. We also compared these changes with other concurrent changes that would have affected pellagra mortality or morbidity.

RESULTS

The results show the difficulty of evaluating the effectiveness of a single public health initiative such as food fortification without controlled experimental trials. Nonetheless, the results provide support for the belief that food fortification played a significant role in the elimination of pellagra in the United States.

CONCLUSIONS

Food fortification that is designed to restore amounts of nutrients lost through grain milling was an effective tool in preventing pellagra, a classical nutritional deficiency disease, during the 1930s and 1940s, when food availability and variety were considerably less than are currently found in the United States.

OmpR regulates the stationary-phase acid tolerance response of Salmonella enterica serovar typhimurium

Tolerance to acidic environments is an important property of free-living and pathogenic enteric bacteria. Salmonella enterica serovar Typhimurium possesses two general forms of inducible acid tolerance. One is evident in exponentially growing cells exposed to a sudden acid shock. The other is induced when stationary-phase cells are subjected to a similar shock. These log-phase and stationary-phase acid tolerance responses (ATRs) are distinct in that genes identified as participating in log-phase ATR have little to no effect on the stationary-phase ATR (I. S. Lee, J. L. Slouczewski, and J. W. Foster, J. Bacteriol. 176:1422-1426, 1994). An insertion mutagenesis strategy designed to reveal genes associated with acid-inducible stationary-phase acid tolerance (stationary-phase ATR) yielded two insertions in the response regulator gene ompR. The ompR mutants were defective in stationary-phase ATR but not log-phase ATR. EnvZ, the known cognate sensor kinase, and the porin genes known to be controlled by OmpR, ompC and ompF, were not required for stationary-phase ATR. However, the alternate phosphodonor acetyl phosphate appears to play a crucial role in OmpR-mediated stationary-phase ATR and in the OmpR-dependent acid induction of ompC. This conclusion was based on finding that a mutant form of OmpR, which is active even though it cannot be phosphorylated, was able to suppress the acid-sensitive phenotype of an ack pta mutant lacking acetyl phosphate. The data also revealed that acid shock increases the level of ompR message and protein in stationary-phase cells. Thus, it appears that acid shock induces the production of OmpR, which in its phosphorylated state can trigger expression of genes needed for acid-induced stationary-phase acid tolerance.

Multicenter study of the treatment of erectile dysfunction with transurethral alprostadil (MUSE) in Korea

A Korean multicenter study was conducted to assess the effectiveness of transurethral alprostadil with MUSE in 334 subjects with chronic erectile dysfunction (ED) who were enrolled in 21 clinical centers. Patients with psychogenic impotence comprised about 30% of subjects. Intraurethral alprostadil was titrated in a stepwise fashion in the clinics from 250 to 500 or 1000 mcg based on erectile response and tolerability. The erectile responses were evaluated using an erection assessment scale (score of 1-5). The dose that produced a maximal penile response of score 5 (full rigid erection) or 4 (full tumescence, partial rigidity) was selected for home treatment. Patients who showed partial erection (score of 3) with 1000 mcg were also included in the home-treatment group. In-clinic phase: 198 men (59.3%) had maximal penile responses of score 4 or 5. The rate of maximal responses was not related to patient age, etiology or duration of the ED. A total of 228 (68.3%) men progressed to home treatment. The overall level of comfort of the transurethral alprostadil was rated as uncomfortable or very uncomfortable in 12%. Home phase: During the two-month period of home treatment, 178 (78.1%) men had successful sexual intercourse at least once, and 78.2% of administrations (1976) resulted in successful intercourse. The main causes of drop-out were insufficient erectile response in 27 men (11.8%), adverse reactions (mostly penile or urethral pain) in 7 (3.1%) or both in 7 (3.1%). In conclusion, transurethral alprostadil could be a suitable treatment option for patients with ED regardless of age and etiology of ED. Efficacy in an Asian population (Korea) is comparable to that reported previously in Caucasians.

High endemicity of Metagonimus yokogawai infection among residents of Samchok-shi, Kangwon-do

A small-scale epidemiological survey was undertaken during 1997-1998 on the residents along the Osib-chon (Stream), Samchok-shi (City), Kangwon-do (Province), to evaluate the status of Metagonimus yokogawai infection. A total of 165 fecal samples was collected and examined by cellophane thick smear and formalin-ether sedimentation techniques. The egg positive rate of M. yokogawai was 29.7%, showing a remarkable difference between males (46.6%) and females (16.3%). To obtain the adult flukes of M. yokogawai, 11 egg positive persons were treated with praziquantel and purged with magnesium sulfate. A total of 242,119 adult flukes (average 22,010 per person, 367-119,650 in range) was collected from diarrheic stools, all of which were identified as M. yokogawai. The results show that M. yokogawai is still highly endemic in this area.

A toxoplasmic uveitis case of a 60-year-old male in Korea

A toxoplasmic uveitis case was reported on the focus of impairment of pathological findings and serological antibody titers after chemotherapy. A chief complaint of a 60-year-old male was a decreased and blurred vision in his right eye for 2 weeks after experiencing tremendous stress and fatigue. A steroid therapy for 3 weeks was not effective and the retinal lesion became necrotic. Anti-Toxoplasma gondii antibody titer was checked to be a strong positive by both ELISA and indirect latex agglutination assay (ILA). He was treated with Fansidar F for 8 weeks. His vision improved as the necrotic lesion healed by scarring, but the antibody titers still remained very high without any signs of negative conversion. It is suggested to be a recurrent case of the past asymptomatic infection by presumed immune suppression caused by excessive stress.

Chromosomal localization and sequence variation of 5S rRNA gene in five Capsicum species

Chromosomal localization and sequence analysis of the 5S rRNA gene were carried out in five Capsicum species. Fluorescence in situ hybridization revealed that chromosomal location of the 5S rRNA gene was conserved in a single locus at a chromosome which was assigned to chromosome 1 by the synteny relationship with tomato. In sequence analysis, the repeating units of the 5S rRNA genes in the Capsicum species were variable in size from 278 bp to 300 bp. In sequence comparison of our results to the results with other Solanaceae plants as published by others, the coding region was highly conserved, but the spacer regions varied in size and sequence. T stretch regions, just after the end of the coding sequences, were more prominant in the Capsicum species than in two other plants. High G x C rich regions, which might have similar functions as that of the GC islands in the genes transcribed by RNA PolII, were observed after the T stretch region. Although we could not observe the TATA like sequences, an AT rich segment at -27 to -18 was detected in the 5S rRNA genes of the Capsicum species. Species relationship among the Capsicum species was also studied by the sequence comparison of the 5S rRNA genes. While C. chinense, C. frutescens, and C. annuum formed one lineage, C. baccatum was revealed to be an intermediate species between the former three species and C. pubescens.

In vitro antimicrobial activity of propolis and Arnica montana against oral pathogens

Arnica and propolis have been used for thousands of years in folk medicine for several purposes. They possess several biological activities such as anti-inflammatory, antifungal, antiviral and tissue regenerative, among others. Although the antibacterial activity of propolis has already been demonstrated, very few studies have been done on bacteria of clinical relevance in dentistry. Also, the antimicrobial activity of Arnica has not been extensively investigated. Therefore the aim here was to evaluate in vitro the antimicrobial activity, inhibition of adherence of mutans streptococci and inhibition of formation of water-insoluble glucan by Arnica and propolis extracts. Arnica montana (10%, w/v) and propolis (10%, w/v) extracts from Minas Gerais State were compared with controls. Fifteen microorganisms were used as follows: Candida albicans--NTCC 3736, F72; Staphylococcus aureus--ATCC 25923; Enterococcus faecalis--ATCC 29212; Streptococcus sobrinus 6715; Strep. sanguis--ATCC 10556; Strep. cricetus--HS-6; Strep. mutans--Ingbritt 1600; Strep. mutans--OMZ 175; Actinomyces naeslundii--ATCC 12104, W 1053; Act. viscosus OMZ 105; Porphyromonas gingivalis; Porph. endodontalis and Prevotella denticola (the last three were clinical isolates). Antimicrobial activity was determined by the agar diffusion method and the zones of growth inhibition were measured. To assess cell adherence to a glass surface, the organisms were grown for 18 h at 37 degrees C in test-tubes at a 30 degree angle. To assay water-insoluble glucan formation, a mixture of crude glucosyltransferase and 0.125 M sucrose was incubated for 18 h at 37 degrees C in test-tubes at a 30 degree angle. Arnica and propolis extracts (20 microl) were added to these tubes to evaluate the % of inhibition of cell adherence and water-insoluble glucan formation. The propolis extract significantly inhibited all the microorganisms tested (p < 0.05), showing the largest inhibitory zone for Actinomyces spp. The Arnica extract did not demonstrate significant antimicrobial activity. Cell adherence and water-insoluble glucan formation were almost completely inhibited by the propolis extract at a final concentration of 400 microg/ml and 500 microg/ml, respectively. The Arnica extract showed slight inhibition of the adherence of the growing cells (19% for Strep. mutans and 15% for Strep. sobrinus) and of water-insoluble glucan formation (29%) at these same concentrations. Thus, the propolis extract showed in vitro antibacterial activity, inhibition of cell adherence and inhibition of water-insoluble glucan formation, while the Arnica extract was only slightly active in those three conditions.

Initial and late results of Freedom coronary stent

OBJECTIVES

Initial and late results after implantation of Freedom stents, a balloon expandable stainless steel coil stents were evaluated.

METHODS

From Jun. 1996 to Nov. 1997, we implanted 123 Freedom stents in 122 lesions in 117 patients and performed follow-up coronary angiograms at 7.0 +/- 3.6 months after stents placement. Clinical courses after stenting and follow-up coronary angiographic findings were evaluated. Comparison of clinical, angiographic, and procedural factors according to the presence or absence of restenosis was performed.

RESULTS

In 117 patients who underwent stents implantation, major complications were not observed. Follow-up coronary angiograms were performed in 47 stents in 41 patients (35%). Among 47 stents, angiographic significant restenosis (percent diameter stenosis > 50%) was observed in 13 (28%). Mean age in 41 patients was 59 +/- 9 years, with 27 male patients (66%). Indications for stents implantation were de novo lesions in 18 (38%), suboptimal results after PTCA in 18 (38%), bail-out lesions in 4 (9%) and restenotic lesions in 7 (15%). Lesion types by AHA/ACC classification were A in 1 (1%), B1 in 10 (21%), B2 in 17 (36%), and C in 19 (40%). Average lesion length was 13.7 +/- 9.0 mm, stent diameter 3.0 +/- 0.3 mm, and stent length 24.6 +/- 9.0 mm. There were no significant differences of the clinical, angiographic, and procedural characteristics according to the presence or absence of restenosis.

CONCLUSION

Freedom coronary stents implantation is safely performed in various morphology of coronary lesions and no significant predictive factors on restenosis in follow-up coronary angiogram were observed.

Restriction fragment length polymorphism analysis of Mycobacterium tuberculosis isolated from countries in the western pacific region

A total of 422 Mycobacterium tuberculosis isolates from eight countries were subjected to IS6110 and IS1081 DNA fingerprinting by means of restriction fragment analysis to characterize M. tuberculosis strains from each country. Chinese, Mongolian, Hong Kong, Filipino, and Korean isolates had comparatively more copies of IS6110 (proportion with eight or more copies; 95% +/- 5%), while Thai, Malaysian, and Vietnamese isolates had fewer copies (proportion with eight or more copies, 60% +/- 4%). We found a number of novel IS1081 types in this study. One IS1081 type was present in 56% of Filipino isolates, had a specific 6.6-kb PvuII fragment in its IS6110 DNA fingerprint, and was termed the "Filipino family." The IS1081 types of Thai isolates had interposing characteristics between the characteristics of northeastern Asian and southeastern Asian IS1081 types. A 1.3-kb single-copy IS6110 fragment was found only in Vietnamese M. tuberculosis isolates. Although M. tuberculosis isolates from each country had comparatively similar characteristics depending on the classification factor, each country's isolates showed characteristic DNA fingerprints and differed slightly from the isolates from the other countries in either the mode number of IS6110 copies or the distribution of IS1081 types.

Mutational alteration of the p16CDKN2a tumor suppressor gene is infrequent in Ewing's sarcoma

Mutational alteration of the p16CDKN2a tumor suppressor gene has been frequently observed in a variety of human cell lines and tumor tissues. To assess whether alterations of the p16CDKN2a gene play an important role in the pathogenesis of Ewing's sarcoma, we examined the allelic deletion and point mutation of the gene in 27 primary tumors. In quantitative DNA/PCR analysis for three individual exons of the gene, none of the 27 specimens showed detectable reduction in the amplification levels compared to those of normal lymphocytes. To explore the presence of any subtle sequence changes within the protein coding region, we performed a comprehensive screening of sequence alteration in the three exons using DNA/PCR-SSCP analysis. However, no abnormal shift of SSCP bands indicative of sequence change was identified. In addition, no elevation of p16CDKN2a mRNA expression was observed in the RD-ES cell line following 5'-Aza-cytidine treatment, indicating that the promoter of the gene is not abnormally methylated in this cell line. Immunohistochemical study of the same tissue specimens for p16CDKN2a and pRB also revealed grade 2+ or 3+ nuclear staining of both proteins in most of the specimens we examined. Taken together, our results strongly suggest that the mutational inactivation of the p16CDKN2a gene might be a rare event, and thus not play a critical role in the pathogenesis of Ewing's sarcoma.

Primary alveolar soft part sarcoma of bone

AIMS

Alveolar soft part sarcoma is a distinct, rare soft tissue tumour occurring primarily within the skeletal muscles or musculofascial planes in young adults. Primary involvement of bone is extremely rare. We report on six patients with alveolar soft part sarcoma occurring primarily in bone.

METHODS AND RESULTS

Thorough clinical and radiographic examinations were done to rule out any other primary site. The patients were four women and two men aged 17-35 years (mean, 24.5 years). The primary site of the tumour was the femur in three patients, the ilium in one and the fibula in two. In one of the patients with fibular involvement, the tibia was also involved by direct extension. Of the long bone lesions, three were centred in the metaphysis and one in the diaphysis. Radiographically, all of the lesions demonstrated an osteolytic pattern of bone destruction with ill-defined margins and a wide zone of transition between the lesion and adjacent normal bone. Microscopically, all tumours showed the typical histological pattern of alveolar soft part sarcoma. Diastase-resistant, periodic acid-Schiff-positive crystalline structures were identified within the cytoplasm and confirmed ultrastructurally. Immunohistochemically, a keratin stain was negative in all cases; there was positive staining for MyoD1 in the cytoplasm but not the nuclei. Distant metastasis developed in four patients; one died.

CONCLUSION

Alveolar soft part sarcoma arising in bone is extraordinarily rare but should be considered in the differential diagnosis of metastatic hypernephroma in a young patient.

Instrumented facet fusion for the degenerative lumbar disorders

A new, simple, minimally morbid procedure used to treat degenerative lumbar spinal disorders is described. The authors based their treatment on the McBride technique of facet fusion, which was modified and supplemented with pedicle screw fixation. The first 32 consecutive patients with degenerative spondylolisthesis and failed back surgery syndrome were treated, and followed for more than a year. Surgically, 26 patients had a single level fusion, and 6 patients had a two level fusion. Postoperative radiographs and computed tomography (CT) scans were evaluated to determine the fusion status. There were no specific complications related with the facet fusion. Thirty of 32 (93.8%) had solid fusions according to the computed tomographic criteria. Two patients showed a questionable union on CT scan but motion was less than 5 degrees on dynamic films. While 96.2% (25/26) of patients with a single level procedure had solid fusion, rate of union in the patients with two level procedures was 83.3% (5/6). This preliminary study of 32 patients shows that instrumented facet fusion appears to be a safe and effective procedure for lumbar spine fusions, demonstrating a high fusion rate with rarely serious complications.

Chondroblastoma of the temporal bone: a clinicopathologic study of five cases

Chondroblastoma is a rare benign bone tumor. It commonly affects the epiphysis of long bones during the second and third decades of life. Chondroblastoma of the temporal bone is extremely rare. We reviewed five cases of chondroblastoma arising in the temporal bone. Four cases were female and one was male. The ages ranged from 41 to 60 years (mean, 53.6 years). All cases involved the temporal bone. Three involved the left side and two the right. Chief complaints were long-standing localized pain and hearing difficulty. A sharply demarcated lobulated mass was the main radiological finding. Microscopic findings were those of chondroblastoma of usual locations. Two cases showed aneurysmal bone cyst-like areas. Immunohistochemical studies for CD34, CD99, S-100 protein and cytokeratin were performed. Tumor cells were diffusely positive for S-100 protein in three cases and weakly positive for cytokeratin in one case. CD34 and CD99 were negative in all cases. In summary, chondroblastoma of the temporal bone is rare and occurs in older age group than reported cases of chondroblastoma of the usual location in the literature.

Parosteal osteosarcoma of the scapula

Parosteal osteosarcoma is a low-grade osteosarcoma, which occurs on the surface of the bone. We had experienced a parosteal osteosarcoma involving the flat bone, the scapula of a 21-year-old man. This is an extremely rare location for a parosteal osteosarcoma. Plain radiograph showed broad-based, well-defined radiodense lesion at the scapula. Computed tomogram demonstrated an intact cortex and absence of a medullary involvement. Tumor showed a lobulated, high-density lesion, indicating bone formation. Histologically, parosteal osteosarcoma is a well-differentiated osteosarcoma. The tumor is composed of a hypocellular proliferation of spindle cells, with minimal cytologic atypia. The bone is in the form of a well-formed bony trabeculae. Occasional cartilage is present in the form of a cap.

A case with intrahepatic double cancer: hepatocellular carcinoma and cholangiocarcinoma associated with multiple von Meyenburg complexes

Combined hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC) is sometimes found in resected livers, however, cases with double cancer of HCC and CC are very rare. As well, the rarity of CC arising in von Meyenburg complexes (VMCs) is appreciated. We report the case of a 74-year-old man found to have intrahepatic double cancer composed of well-differentiated HCC and CC which exhibited a histologic progression from VMCs to adenomatous lesions and CC. To our knowledge, this is the first case report published in the literature of a double HCC and CC associated with multiple VMCs. The pathogenesis and previous associated reports of these lesions are discussed.

Chondroblastoma: MR characteristics with pathologic correlation

PURPOSE

The purpose of this study was to describe the MR findings of chondroblastoma with pathologic correlation.

METHOD

In 22 patients with pathologically proven chondroblastoma, MR signal characteristics were correlated with pathological findings.

RESULTS

On T2-weighted images, 12 (55%) lesions were hyperintense with hypointense areas in 9 lesions, whereas 10 (45%) were hypointense. Therefore, 19 of 22 (86%) lesions with pathologic correlation had hypointense areas entirely (n = 10) or partly (n = 9) on T2-weighted images. On gadolinium-enhanced images, 13 (59%) lesions showed lobular enhancement and 9 (41%) showed marginal and septal enhancement. Low signal intensity on T2-weighted MR images was most strongly associated with an abundance of immature chondroid matrix, hypercellularity of the chondroblasts, calcifications, and hemosiderin on histology.

CONCLUSION

Chondroblastoma was found to show hypointense portions on T2-weighted images. Signal intensity on T1- and T2-weighted MR images in chondroblastoma was dependent on the amounts of histopathological components.

Effect of Apis mellifera propolis from two Brazilian regions on caries development in desalivated rats

The purpose of the present study was to evaluate the effect of Apis mellifera propolis collected from two regions of Brazil on caries development in desalivated rats. Ethanolic extracts of propolis (EEP) were prepared from crude propolis samples collected in Minas Gerais state (MG), southeastern Brazil, and Rio Grande do Sul state (RS), southern Brazil. The flavonoid composition of EEP was analyzed by high-performance thin-layer chromatography (HPTLC) and reversed-phase high-performance liquid chromatography (HPLC). For the animal study, 30 specific pathogen-free Wistar rats were infected with Streptococcus sobrinus 6715 and surgically desalivated. The rats were randomly divided into three groups which were treated with 80% ethanol (control), EEP from MG and EEP from RS. The animals were placed in a König-Höfer programmed feeder and received 17 meals of diet 2000 daily at hourly intervals. The solutions were applied on the rat molars (25 microl on molars of each quadrant) twice a day, by using graduate syringes. After 3 weeks, the animals were killed by CO(2) asphyxiation. For microbial assessment, the left jaw was removed and sonicated in 154 mM NaCl solution. Dental caries was evaluated according to Larson's modification of Keyes' system. The HPTLC patterns and HPLC profiles demonstrated that both quality and quantity of flavonoid aglycones of EEP from MG were different compared to EEP from RS. In general, it is apparent that EEP from RS contained the highest concentrations of pinocembrin, chrysin, acacetin and galangin. The group of animals treated with EEP from RS showed the lowest smooth-surface and sulcal caries scores as well as less caries severity in smooth-surface and sulcal lesions, and these data were statistically different when compared with the control group. The group treated with EEP from MG only demonstrated a significant difference in the severity of sulcal lesions when compared to the control group. The percentage of S. sobrinus was lower in the groups treated with EEP, but did not differ statistically from the control group. The results showed that the cariostatic effect of propolis depends on its composition, and consequently the region of collection of propolis samples.