Biological behavior and tumorigenesis of subependymal giant cell astrocytomas

In spite of the benign nature of subependymal giant cell astrocytomas (SEGAs), some show massive hemorrhage, rapid growth, and tumor recurrence. This led us to investigate the biological behavior, cell dynamics, and tumorigenesis of SEGAs. All patients (4 men and 3 women; age range, 6-27 years; mean, 13.6 years) had features of tuberous sclerosis complex and obstructive hydrocephalus. One patient had intratumoral bleeding. In two patients, sequential neuroimaging showed a subependymal nodule growing to become a SEGA. All underwent surgical resection without radiation therapy. One tumor recurred and was treated surgically. There were no postoperative deaths. The presence of cytologic atypia, mitoses and vascular proliferation had no implication in terms of the clinical course. MIB-1 labeling indices were low (mean, 0.9), indicating low proliferative potential. Unexpectedly, bcl-2 staining was sparse and bax staining predominated in majority of cases. However, the mean value of terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling index was low. Immunohistochemically, tumors were positive for both glial and neuronal markers. In the majority of our cases, the expression of p53 was low. Only one tumor was focally positive for tuberin. SEGAs have low proliferative potential and apoptotic activity, and exhibit features of mixed glial-neuronal differentiation. In contrast to p53, tuberin is suggested to be the tumor suppressor in this tumor.

Association of vitamin D receptor and estrogen receptor gene polymorphisms with bone mass in postmenopausal Korean women

OBJECTIVE

To examine the relationship between vitamin D receptor (VDR) and estrogen receptor (ER) gene polymorphism and bone mineral density (BMD).

DESIGN

Polymorphisms at the VDR FokI and ER PvuII and XbaI gene sites, serum bone-specific alkaline phosphatase, urinary N-telopeptide of type I collagen, and BMD at the lumbar spine and proximal femur were analyzed in 229 postmenopausal Korean women.

RESULTS

The distribution of ER PvuII and XbaI and VDR FokI restriction fragment length polymorphisms was as follows: pp 39.3%, Pp 46.3%, PP 14.4%, xx 34.1%, Xx 61.1%, XX 4.8%. ff 17.0%, Ff 43.7%, and FF 39.3%, respectively (upper-case letters signify the absence, and lower-case letters signify the presence of the restriction site). After adjusting for potential confounding factors such as age, body mass index, and menopause duration, ER PvuII was independently associated with BMD at the lumbar spine and XbaI polymorphism BMD at the femoral neck. The lumbar spine BMD in the pp genotype was 7.5% lower than in the PP genotype, and the femoral neck BMD was 4.8% lower in the Xx genotype than in the xx genotype. By itself, the VDR FokI polymorphism was not related to BMD, but by combining the FokI genotype (FF) with ER genotypes, such as ppxx and the PpXx, the difference in the BMD at the Ward's triangle became significant. There were no significant differences in the levels of biochemical markers between the genotypes of three polymorphisms.

CONCLUSION

ER polymorphisms, singly and in relation to VDR FokI polymorphism, influence bone mass in Korean women.

Structural basis of non-specific lipid binding in maize lipid-transfer protein complexes revealed by high-resolution X-ray crystallography

Non-specific lipid-transfer proteins (nsLTPs) are involved in the movement of phospholipids, glycolipids, fatty acids, and steroids between membranes. Several structures of plant nsLTPs have been determined both by X-ray crystallography and nuclear magnetic resonance. However, the detailed structural basis of the non-specific binding of hydrophobic ligands by nsLTPs is still poorly understood. In order to gain a better understanding of the structural basis of the non-specific binding of hydrophobic ligands by nsLTPs and to investigate the plasticity of the fatty acid binding cavity in nsLTPs, seven high-resolution (between 1.3 A and 1.9 A) crystal structures have been determined. These depict the nsLTP from maize seedlings in complex with an array of fatty acids.A detailed comparison of the structures of maize nsLTP in complex with various ligands reveals a new binding mode in an nsLTP-oleate complex which has not been seen before. Furthermore, in the caprate complex, the ligand binds to the protein cavity in two orientations with equal occupancy. The volume of the hydrophobic cavity in the nsLTP from maize shows some variation depending on the size of the bound ligands. The structural plasticity of the ligand binding cavity and the predominant involvement of non-specific van der Waals interactions with the hydrophobic tail of the ligands provide a structural explanation for the non-specificity of maize nsLTP. The hydrophobic cavity accommodates various ligands from C10 to C18. The C18:1 ricinoleate with its hydroxyl group hydrogen bonding to Ala68 possibly mimics cutin monomer binding which is of biological importance. Some of the myristate binding sites in human serum albumin resemble the maize nsLTP, implying the importance of a helical bundle in accommodating the non-specific binding of fatty acids.

Effect of exercise intensity and frequency on lipid levels in men with coronary heart disease: Training Level Comparison Trial

The objective of the Training Level Comparison Trial was to determine whether a more intense exercise program versus a less intensive program has additional favorable effects on blood lipids in men with coronary heart disease (CHD) over a 12-month period. The study-a randomized, controlled trial conducted at 2 clinical centers-enrolled 185 patients with documented CHD. A simple randomization procedure led to unequal numbers of patients in the 2 interventions: 82 in the low-intensity and 103 in the high-intensity group. Target heart rate during exercise corresponded to 50% of maximum oxygen uptake (VO(2 max)) +/- 5 beats/min in the low-intensity group and 85% +/- 5 beats/min in the high-intensity group. The intensity of exercise made little difference on lipid improvements. However, the attendance rates for the 6- and 12-month periods (percentage of total exercise sessions attended) were significantly related to increased high-density lipoprotein (HDL) cholesterol (r(s) [Spearman rank correlation coefficient 0.20 to 0.26, p <0.05]), and decreases in the ratios of low-density lipoprotein (LDL)-to-HDL cholesterol (LDL:HDL, r(s) = -0.24 to -0.28, p < 0.01) and total-to-HDL cholesterol (total:HDL, r(s) = -0.25 to -0.29, p < 0.01) at 6 and 12 months. The relation of the attendance rate to LDL:HDL and total:HDL ratios remained significant in repeated-measures regression analysis. Exercise frequency may be more important than intensity in improving HDL cholesterol and LDL:HDL and total:HDL ratios in men with CHD.

Novel sulfonate analogues of combretastatin A-4: potent antimitotic agents

Sulfonate analogues of combretastatin A-4 have been prepared. These compounds compete with colchicine and combretastatin A-4 for the colchicine binding site on tubulin and are potent inhibitors of tubulin polymerization and cell proliferation. Importantly, these compounds also inhibit the proliferation of P-glycoprotein positive (+) cancer cells, which are resistant to many other antitumor agents.

Crystallization and preliminary X-ray crystallographic analysis of the surE protein from Thermotoga maritima

The surE protein from Thermotoga maritima is a 247-residue protein of unknown function. Its homologues are well conserved among both the eubacteria and the archaea. It has been overexpressed in soluble form in Escherichia coli. The protein has been crystallized at 296 K using 2-propanol as a precipitant. X-ray diffraction data have been collected to 1.9 A resolution using synchrotron radiation. The crystals belong to the trigonal space group P3(1)21 (or P3(2)21), with unit-cell parameters a = b = 115.96, c = 78.60 A, alpha = beta = 90, gamma = 120 degrees. The asymmetric unit contains two monomers of the surE protein, with a corresponding V(M) of 2.72 A(3) Da(-1) and a solvent content of 54.7%.

Tic convulsif caused by cerebellopontine angle schwannoma

A case is presented of painful tic convulsif caused by schwannoma in the cerebellopontine angle (CPA), with right trigeminal neuralgia and ipsilateral hemifacial spasm. Magnetic resonance images showed a 4 cm round mass displacing the 4th ventricle and distorting the brain stem in the right CPA. The schwannoma, which compressed the fifth and seventh cranial nerves directly, was subtotally removed by a suboccipital craniectomy. Postoperatively, the patient had a complete relief from the hemifacial spasm and marked improvement from trigeminal neuralgia. The painful tic convulsif in this case was probably produced by the tumor compressing and displacing the anterior cerebellar artery directly.

Nuclear localization of beta-catenin is an important prognostic factor in hepatoblastoma

In this study, mutational and immunohistochemical analyses of beta-catenin were performed in 30 hepatoblastomas, to assess the prevalence of alterations of the Wnt pathway with respect to clinicopathological parameters and survival. Four missense mutations of beta-catenin (13.3%) were detected and there was strong immunoreactivity for beta-catenin in the cytoplasm and/or the nucleus in 97% of hepatoblastomas. Nuclear and cytoplasmic staining was demonstrated in 19 of 30 tumours (63%), while ten revealed only cytoplasmic staining. Statistically, this nuclear beta-catenin staining was significantly higher in the embryonal (Fisher exact test; p=0.00393) or undifferentiated type (p=0.00156) of hepatoblastoma than in the fetal type, but there was no difference between clinical stages I and II and clinical stages III and IV (p=0.175). Cumulative survival curves showed that nuclear beta-catenin staining (generalized Wilcoxon test; p=0.0088), undifferentiated histological type (p=0.0305), and clinical stages III and IV (p=0.0107) were significantly correlated with shorter survival time in these patients. Moreover, Cox multivariate analysis provides evidence that nuclear beta-catenin staining is the most important prognostic factor for survival (p=0.0090). It is therefore concluded that immunohistochemical analysis of beta-catenin might be a useful clinical tool for estimating the prognosis for patients with hepatoblastoma.

Erythema induratum: a clinicopathologic and polymerase chain reaction study

BACKGROUND

In Taiwan, cutaneous lesions with granulomatous lobular panniculitis, with or without vasculitis, are usually diagnosed as erythema induratum (EI), a common form of tuberculid associated with tuberculosis. However, there has been no study to elucidate the extent of this association in Taiwan. The aim of this study was to document the spectrum of the pathologic findings in EI and its association with Mycobacterium tuberculosis.

METHODS

The diagnostic/inclusion criteria for EI were recurrent tender subcutaneous nodules on the legs, histopathologic findings of granulomatous lobular or septolobular panniculitis plus necrosis or vasculitis, and positive response to antituberculosis therapy. The clinicopathologic findings in the 12 cases that fulfilled these criteria were analyzed, and nested polymerase chain reaction (PCR) was used to identify M. tuberculosis complex DNA from formalin-fixed, paraffin-embedded sections.

RESULTS

Eleven women and one man were included in the study, ranging from 18 to 70 years old (mean, 40.6 yr). The duration of the disease ranged from 10 days to 10 years (mean, 2.1 yr). Histopathology revealed granulomatous panniculitis; a diffuse lobular pattern was observed in nine cases and a focal lobular/septolobular pattern in three. Vasculitis was found in nine cases, four affecting an artery or vein, with three occurring in the patients with focal panniculitis. Ten cases showed various degrees of caseous necrosis. Eosinophils or focal eosinophilia were fairly common (10 patients). From PCR, nine patients were positive for M. tuberculosis complex DNA.

CONCLUSIONS

Type III and IV hypersensitivity reactions to M. tuberculosis complex were involved in the pathogenesis of EI. Our results suggest that approximately half of the cases with pathologic findings consistent with EI or nodular vasculitis in Taiwan are associated with M. tuberculosis.

Functional inactivation of p73, a homolog of p53 tumor suppressor protein, by human papillomavirus E6 proteins

Human papillomavirus (HPV) is strongly implicated as a causative agent in the etiology of cervical cancer. Of its gene products, E6 binds to and inactivates p53 tumor suppressor protein by ubiquitin/proteasome-dependent degradation. Recently, p73, a novel family of p53, has been identified and demonstrated, like p53, to activate p21(WAF1). Here we show that p73 is also inactivated by HPV-E6, but ubiquitin-mediated proteolysis is not responsive. Yeast two-hybrid and GST pull-down assays indicate a physical interaction between p73 and either HPV-16 or HPV-11 E6 proteins in vivo and in vitro, respectively. The transactivation domain (amino acid residues 1 to 49) is found to be absolutely required for the interaction. Transient co-expression of E6 significantly inhibits the p73-mdiated activation of p21(WAF1) promoter in a p53-defective C33A cell line. Using Gal4-p73 fusion protein, we demonstrate that E6 inhibition of p73 transactivation function is independent of sequence-specific DNA binding, which is confirmed by a direct electrophoretic mobility shift assay. Moreover, E6 inhibits p73 function by interfering with the activity of the amino-terminal activation domain. Co-transfection of E6 mutants reveals that the same portion of E6 appears to be responsible for the inactivation of p53 and p73 function. However, the inactivation mechanism of p73 is clearly different from that of p53, because p73, unlike p53, is inactivated by both high- and low-risk E6s and is not susceptible to E6-dependent proteolysis. These overall results, consequently, suggest that in addition to the inactivation of p53, the functional interference of p73 by HPV-E6 may, at least in part, contribute to E6-mediated transformation and hyperproliferation of cervical cells.

Histological study of lumbar intervertebral disc herniation in adolescents

Herniated intervertebral discs are rare in children and adolescents constituting approximately 1-5% of all patients undergoing surgery for lumbar and lumbosacral intervertebral disc herniation. Preceding traumata and congenital anomalities have been reported as important factors for the pathogenesis of intervertebral disc prolapses in young patients. The present histological study is based upon 15 patients with lumbar disc herniation within an age range from 14 to 19 years. Only in one case, was adequate trauma reported. All patients exhibited degenerative changes of the disc, similiar to those observed in adults. These changes were marked in 11 patients (73%). Thus, as known from adults, also in isolated traumatic disc herniation of adolescence, pre-existing degeneration of the disc has to be considered. If such changes are present, trauma has the significance of only transitory deterioration of the previous disc degeneration.

Sequence variants and functional analysis of human papillomavirus type 16 E5 gene in clinical specimens

Previously, we found that the E5 protein can be expressed in HPV-16 infected precancerous lesions and cervical cancer. In this study, we investigated the presence of sequence variants of E5 in HPV-16 infected tissues. Toward this end, we amplified the E5 gene by polymerase chain reaction from 29 HPV-16 infected tissues including eight normal tissues, seven high grade neoplastic tissues (high grade squamous intraepithelial lesions (HSIL) and 14 cervical cancer tissues. Sequence analysis demonstrated that there were three mutational hot spots at positions 3979, 4042, and 4077 of the HPV-16 DNA; these and other mutations resulted in six variants in the E5 sequence. This resulted in four E5 protein mutants, named WTE5 [wild type E5 protein], 14E5, 21E5 and 56E5. Functional analysis of these four mutant proteins revealed that the transforming activities of 14E5, 21E5 and 56E5 were 0.95, 0.59, and 0.89 fold of WTE5, respectively. Although E5 was expressed in all of the HSIL and cervical cancer tissues, but in only one of the eight normal tissues tested, only WT E5 protein was found in HSIL while in cervical cancer tissues both WT and mutant E5 proteins were detected. Since these E5 proteins exhibited the same in vitro transforming activity, these data suggest that expression of E5 is important in development and progression toward malignancy but mutation of E5 does not affect the transformation process.

Comparison of Abbott AxSYM, Behring Opus Plus, DPC Immulite and Ortho-Clinical Diagnostics Vitros ECi for measurement of cardiac troponin I

Myocardial infarction is a common cause of morbidity and mortality in patients with chest pain. The presence of human cardiac troponin I (cTnI) in serum is considered to be a highly specific biochemical marker of acute myocardial infarction. In this study we compare the performances of the Abbott AxSYM, Behring Opus Plus, DPC Immulite and Ortho-Clinical Diagnostics Vitros ECi for the measurement of cTnI. The first two methods use a fluorogenic enzyme-linked immunoassay. whereas the last two use chemiluminescent immunometric assays. All procedures are completely automated. Total percentage coefficients of variation using pooled sera ranged from 5.9 to 6.5% for the AxSYM, 14.4 to 25.6% for the Opus, 6.9 to 9.8% for the Immulite and 4.5 to 5.2% for the Vitros ECi method. The closest correlation between methods, obtained from 120 fresh serum samples, was observed between the Vitros ECi and the Immulite methods, with r=0.99, and the regression line was Immulite cTnI 1.505 (95% confidence interval 1.474-1.536) x Vitros cTnI--0.154 (-0.702 to 0.394). Receiver operating characteristic curves were nearly identical for all assays, and the areas under the curves were 0.972, 0.927, 0.967 and 0.969 for the AxSYM, Opus, Immulite and Vitros ECi methods, respectively. There was a significant difference between the AxSYM and Opus methods (P= 0.036).

Effects of electrical stimulation of the Gasserian ganglion on regional cerebral blood flow after induced subarachnoid hemorrhage in pigs evaluated by 99mTc-HMPAO-SPECT

It could be demonstrated that cervical spinal cord stimulation increases cerebral blood flow. The effects of electrical stimulation of the trigeminal ganglion in the acute phase of SAH in pigs were investigated. The experiments were carried out on 11 domestic pigs divided in two groups (group I: SAH [n = 5]; group II: SAH and trigeminal stimulation [n = 6]). In all animals a native SPECT was performed. The Gasserian ganglion was exposed for inserting the stimulation electrode. SAH was induced by injecting 10 ml autologous blood through a catheter placed in the suprasellar cistern. 30 minutes after SAH-induction electrical stimulation was started for two hours in group II (2.8-4.5 V, 50 Hz, 300 microseconds). 99mTc-HMPAO (400-540 MBq) was injected intravenously 110 minutes later. In group I 99mTc-HMPAO was applied after the same time interval. 80 minutes later SPECT was performed. Data were processed to calculate the uptake of radioactivity (%/kg tissue weight). The mean values were calculated for the different groups: native animal examination (%/kg tissue weight): 0.6343; group I: 0.468; group II: 0.6533. Comparing the mean values a highly significant difference between group I and group II (p < 0.01) and between native examination and group I (p < 0.01) could be found. No statistical significance could be detected on comparing the left/right-ratio in any ROI. The electrical stimulation of the Gasserian ganglion leads to a significantly increased uptake of 99mTc-HMPAO after induced SAH. Maybe the stimulation of the Gasserian ganglion constitutes a new therapeutic modality treating disturbed rCBF after SAH.

A novel approach to thymidylate synthase as a target for cancer chemotherapy

Tumor cell resistance to fluoropyrimidines and other inhibitors of thymidylate synthase (TS) is a serious problem often associated with increased intracellular TS. Clinically, another problem that arises from the use of TS inhibitors is toxicity, which develops, in part, because normal cells may be adversely affected by doses of inhibitor that do not impact tumor cells. To circumvent this problem, we have devised a new strategy called enzyme-catalyzed therapeutic activation (ECTA), which takes advantage of overexpressed TS to enzymatically generate cytotoxic moieties preferentially in tumor cells. We show herein that tumor cells expressing elevated levels of TS are preferentially sensitive to NB1011, a phosphoramidate derivative of (E)-5-(2-bromovinyl)-2'-deoxyuridine. We find support for the proposed mechanism of NB1011 in the following results: 1) positive relationship between TS protein level and sensitivity to NB1011 in engineered HT1080 tumor cells, designed to express defined levels of TS protein; 2) NB1011 activity is enhanced on tumor cells which express endogenous elevated TS; 3) cytotoxicity of NB1011 is blocked by raltitrexed (Tomudex); 4) NB1011 selection of TS-overexpressing MCF7TDX tumor cells results in recovery of cell populations and clones with diminished TS levels (and restored sensitivity to raltitrexed). A preliminary comparison of TS mRNA levels in multiple normal tissues versus colon tumor samples suggests that selective tumor cytotoxicity of NB1011 may be possible in the clinical setting. Because NB1011 cytotoxicity is dependent upon activation by TS, its proposed mechanism of action is distinct from current TS-targeted drugs, which require inhibition of TS to be effective.

The properties of the ultramicrocylindrical ionization chamber for small field used in stereotactic radiosurgery

Accurate dosimetry of small-field photon beams tends to be difficult to perform due to the presence of lateral electronic disequilibrium and steep dose gradients. In stereotactic radiosurgery (SRS), small fields of 6-30 mm in diameter are used. Generally thermoluminescence dosimetry chips, Farmer, Thimble ion chamber, and film dosimetry are not adequate to measure dose in SRS beams. These techniques generally do not provide the required precision due to their energy dependence and/or poor resolution. It is necessary to construct a small, accurate detector with high spatial resolution for the small fields used in SRS. The ultramicrocylindrical ionization chamber (UCIC) with a gold wall of 2.2 mm in diameter and 4.0 mm in length has dual sensitive volumes of air (8.0 mm3) and borosilicate (2.6 mm3) cavity. Reproducibility, linearity, and radiation damage with respect to absorbed dose, beam profile of small beam, and independence of dose rate of the UCIC are tested by the dose measurements in high energy photon (5, 15 MV) and electron (9 MeV) beams. The UCIC with a unique supporting system in the polystyrene phantom is demonstrated to be a suitable detector for the dose measurements in a small beam size.

Oral gabapentin (neurontin) treatment of refractory genitourinary tract pain

PURPOSE

Refractory genitourinary pain is a common but difficult condition to treat. Examples of chronic genitourinary pain include orchalgia, interstitial cystitis, pain after bladder suspension surgery, nonbacterial prostatitis, and genital pain related to lumbosacral neuropathy. We report our experience with oral gabapentin treatment for this condition. Gabapentin is an anticonvulsant with unclear but therapeutic effects on neurologic pain.

MATERIALS AND METHODS

Twenty-one patients referred with refractory genitourinary pain were treated with oral gabapentin. There were 9 men and 12 women. In the male patients, the location of pain was testicle (4), bladder (2), penis (1), or prostate (2). In female patients, the pain was located in the urethra (4), bladder (6), vulva (1), or vagina (1). The dose of gabapentin was titrated from 300 up to 2,100 mg/day. Subjective pain severity and 10-cm visual pain scale was used before and 6 months after therapy.

RESULTS

The mean dose of gabapentin was 1,200 mg/day (range 300-2,100 mg). Ten of 21 patients reported subjective improvement of their pain. The remaining patients did not perceive any improvement. Gabapentin was well tolerated; only 4 patients dropped out due to side effects. The most common adverse effects were dizziness and drowsiness. Five of 8 patients with interstitial cystitis reported improvement.

CONCLUSIONS

Although only 10 of 21 patients improved with gabapentin, this cohort included only patients with refractory genitourinary pain that failed a wide range of prior treatments. Gabapentin belongs in the armaterium of the urologist who treats genitourinary pain.

6,7-Bis(bromomethyl)-2,11,18,21,24-pentaoxatetracyclo

The 17-crown-5 unit, C(26)H(26)Br(2)O(5), consisting of a 1,2-bis(bromomethyl) group, three benzo groups and diethylene glycol, was prepared from the reaction of 1,2,4,5-tetrakis(bromomethyl)benzene and bis-phenol in the presence of sodium hydride as a base. This molecule seems to offer an internal cavity for the formation of a host--guest complex.

Expression of Fas and Fas-related molecules in human hepatocellular carcinoma

Many tumor cells, including hepatocellular carcinoma (HCC), express both Fas and its ligand on their surfaces, and it has remained a mystery why such cells do not spontaneously become apoptotic. In the current study, we analyzed the alterations of Fas structure and the expression of Fas and Fas ligand (FasL) and of Fas pathway inhibitors, including soluble Fas (sFas), Fas-associated phosphatase-1 (FAP-1), and bcl-2, in 50 cases of human HCC. Monoallelic loss of the Fas gene, as determined by loss of heterozygosity with intragenic polymorphisms, was observed in 5 of the 34 informative cases (15%), but none of the 50 cases showed Fas gene mutation. Expression of Fas and FasL was detected in 44 (88%) and 50 (100%) cases, respectively. sFas messenger RNA, as analyzed by in situ reverse-transcription polymerase chain reaction was expressed in 42 of the 50 cases (84%), and FAP-1 expression was observed in 40 of the 50 cases (80%). In contrast, none of the 50 cases showed bcl-2 expression. Our results showed that the majority of the HCCs (88%) coexpressed a death receptor, Fas and its cognate ligand, FasL, but all HCCs showed one or more alterations of the Fas pathway molecules known to inhibit Fas-mediated apoptosis. These findings suggest that the expression of sFas and FAP-1 and, in part, loss of Fas expression, rather than Fas gene alteration or bcl-2 expression, may be involved in the Fas resistance of HCC in vivo and that these mechanisms may play important roles in the pathogenesis of human HCC. HUM PATHOL 32:250-256.

Association of the vitamin D receptor start codon polymorphism (FokI) with bone mineral density in postmenopausal Korean women

We undertook this study in order to examine the association between bone mineral density (BMD) and a polymorphism at the first of two potential translation initiation codons in the vitamin D receptor (VDR) gene. This polymorphism was detected by restriction fragment length polymorphism analysis, using polymerase chain reaction (PCR) and the restriction endonuclease FokI. The f allele indicates the presence of the FokI site, and the F allele its absence. The FokI genotype was determined in 174 postmenopausal Korean women, aged 43-71 years. The distribution of FokI genotypes in Koreans was found not to differ significantly from those found in Caucasians and Japanese, although it does differ significantly from that found in the black American population. We observed a significant association between the FokI polymorphism and lumbar BMD; P = 0.048, analysis of covariance [ANCOVA], but no association with femoral neck BMD (P = 0.505, ANCOVA). Those with the ff genotype had a 13.3% lower BMD in the lumbar spine than the FF subjects. In addition, a significantly higher prevalence of the ff genotype was observed in osteoporotic compared with osteopenic or normal women (P = 0.036, chi2 test). These data suggest that the ff genotype of the VDR gene correlates with decreased BMD in the lumbar spine in postmenopausal Korean women.

Depigmented genital extramammary Paget's disease: a possible histogenetic link to Toker's clear cells and clear cell papulosis

BACKGROUND

The histogenesis of extramammary Paget's disease (EMPD) is still controversial. Benign pagetoid cells of the nipple first described by Toker and the similar clear cells found in white maculopapules of clear cell papulosis (CCP) have been proposed to be potential precursor cells giving rise to EMPD and primary intraepidermal Paget's disease in the nipple. The observation of a rare case of depigmented EMPD provided us with a chance to examine further the interesting Toker's clear cell/CCP hypothesis.

METHODS

We performed pathologic studies, including Fontana-Masson stain and immunostaining for AE1/AE3 and S100P, on a new case of depigmented EMPD manifesting a 4 x 3 cm hypopigmented-depigmented patch on the root of the penis.

RESULTS

The lesion showed extensive intraepithelial proliferation of atypical pagetoid cells with markedly reduced epidermal melaninization but nearly normal numbers of melanocytes. The tumor cells were strongly positive for AE1/AE3 by immunostaining. Some tumor cells displayed tadpole-like morphology resembling the pagetoid cells of CCP. Such morphology was not observed in two random examples of non-depigmented genital EMPD.

CONCLUSIONS

The findings of tadpole-shaped pagetoid cells and depigmentation in the present case suggest that depigmented EMPD may be histogenetically related to CCP. Depigmented EMPD should be considered in the differential diagnosis of vitiligo, depigmented mycosis fungoides and lichen sclerosus located along the milk line.

Somatic mutations in the death domain of the Fas (Apo-1/CD95) gene in gastric cancer

It is now believed that genes regulating apoptosis are also important variables in cancer development. Fas, a transmembrane protein of the tumour necrosis factor receptor family, is a key molecule for cell death signalling. The mutation of the primary structure of the Fas gene might also be one of the possible mechanisms that disrupt Fas-mediated apoptosis in tumour cells. The purpose of this study was to determine whether somatic mutation of the Fas gene could be involved in the tumourigenesis of gastric cancer. Polymerase chain reaction (PCR)-based loss of heterozygosity (LOH) analysis with two intragenic polymorphic markers, and mutation analysis for the entire coding regions of the Fas gene were performed in 43 cases of gastric cancer, using PCR-single-strand conformational polymorphism sequencing. Five (11.6%) missense mutations were detected, only in the death domain of the Fas gene. Although these mutations were observed only in intestinal-type gastric cancers, there was no statistically significant difference in the frequency of Fas mutation between intestinal- and diffuse-type gastric cancer (p=0.068). Nine LOH out of 22 informative cases were also detected with one or both markers (41%). Three of them demonstrated a somatic mutation in the remaining allele, indicating the inactivation of both alleles. These results suggest that genetic alterations of the Fas gene may not only be limited to gastric cancer cell protection through Fas resistance, but may also play an important role in tumour promotion and/or progression in a subset of gastric cancer.

Somatic mutations of TRAIL-receptor 1 and TRAIL-receptor 2 genes in non-Hodgkin's lymphoma

Tumor necrosis factor-related apoptosis-inducing ligand-receptor 1 (TRAIL-R1) and tumor necrosis factor-related apoptosis-inducing ligand-receptor 2 (TRAIL-R2) are cell-surface receptors involved in tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced cell-death signaling. TRAIL-R1 and TRAIL-R2 genes have recently been mapped to chromosome 8p21-22, which is a frequent site of allelic deletions in many types of human tumors, including non-Hodgkin's lymphoma (NHL). Because TRAIL/TRAIL receptor system plays an important role in lymphocyte homeostasis, we hypothesized that the mutations of TRAIL-R1 and TRAIL-R2 may be involved in the development of NHL and that such mutations may be responsible for the allelic losses of 8p21-22 in NHL. In this study, we analysed the entire coding region of TRAIL-R2 gene and the death domain region of TRAIL-R1 gene for the detection of the somatic mutations in a series of 117 human NHLs using polymerase chain reaction (PCR)-based single strand conformation polymorphism (SSCP) analysis. Overall, eight tumors (6.8%) were found to have two TRAIL-R1 gene mutations or six TRAIL-R2 gene mutations. Interestingly, of the eight mutations, six missense mutations (two TRAIL-R1 and four TRAIL-R2) were detected in the death domains and one nonsense mutation of TRAIL-R2 was detected just before the death domain. Our data suggest that somatic mutations of TRAIL-R1 and TRAIL-R2 genes may play a role in the pathogenesis of some NHLs and that TRAIL-R1 and TRAIL-R2 genes might be the relevant genes to the frequent loss of chromosome 8p21-22 in human NHL.

Clinical evaluation of and parental satisfaction with resin-faced stainless steel crowns

PURPOSE

This study evaluated the clinical success and parental acceptance of anterior primary dentition caries treatment with prefabricated resin-faced stainless steel crowns.

METHODS

A retrospective analysis of maxillary anterior primary dentition caries treatment using Whiter Biter II Crowns was performed. Each crown was evaluated for retention, fracture, interface failure, color match, marginal integrity, and surface texture. Parental satisfaction regarding the esthetics of the crowns was evaluated by survey.

RESULTS

Thirty-eight crowns were evaluated in 12 children. The average crown age at time of examination was 20.7 months. Three teeth were lost to trauma with all other crowns remaining intact. Twelve crowns (32%) showed loss of at least some facial resin. Nine crowns (24%) had complete loss of the resin facing. Overall parental satisfaction with the treatment was excellent, however, satisfaction with crown esthetics received the lowest rating.

CONCLUSIONS

While parental satisfaction with treatment of anterior primary dentition caries with prefabricated resin-faced stainless steel crowns is excellent, the high failure rate of the resin facings is problematic.