Histologic study of effects of radiation synovectomy with Rhenium-188 microsphere

Rhenium-188 microsphere is a relatively new radiation synovectomy agent developed for the treatment of rheumatoid arthritis. It has been shown that the levels of unwanted extra-articular radiation are negligible with this agent. A histologic study was conducted to assess the effect of radiation synovectomy on synovium and articular cartilage after intra-articular injection of various doses of Re-188 microspheres into the knee joints of rabbits. Intra-articular injection of Re-188 microspheres into rabbit knee joints resulted in mild reactive inflammation and thrombotic occlusion of vessels which subsided rapidly. Sclerosis of subsynovium could be seen 12 weeks after injection. No evidence of damage to articular cartilage was noted. There was no significant difference in the articular pattern after injection of 0.3 or 0.6 mCi Re-188 microspheres. This study suggests that a treatment dose of Re-188 microspheres causes transient inflammation of synovium without any detectable damage to the articular cartilage of knee joint.

Effects of ipriflavone on bone loss following a bilateral ovariectomy and menopause: a randomized placebo-controlled study

A randomized placebo controlled study was undertaken to evaluate the effect of ipriflavone (IP) against the bone loss in premenopausal ovariectomized women and postmenopausal women. Thirty-seven Japanese women who underwent premenopausal bilateral ovariectomy within 3 months (early stage group) and 52 Japanese women who were ovariectomized or who had undergone menopause more than 3 years before the start of the study (late stage group) were enrolled. The patients were randomly allocated into two groups: those who received IP (600 mg/day) and those who received placebo. The bone mineral density (BMD) of the lumbar vertebrae was measured by dual energy X-ray absorptiometry, and the markers of bone metabolism were measured at the same time that BMD was measured. In the early stage group, the IP group showed a 6.7% decrease in BMD from baseline levels, whereas the placebo group showed a 10.7% decrease (P < 0.01) at 12 months of treatment, and 7.1% and 12.6% decrease at 24 months of treatment, respectively (P < 0.01). In the late stage group, there was a 0.3% increase in BMD in the IP group and a 2.3% decrease in the placebo group at 6 months of treatment (P < 0.01), and similar changes were seen at 18 months (1.4% increase and 3.9% decrease; P < 0.01). IP suppressed bone loss compared with placebo, however, did not prevent acute bone loss in the early stage following ovariectomy. The effect of IP alone on bone loss in the early stage is not sufficient to reduce the risk of osteoporosis in later life.

Structure and expression of an amylopullulanase gene from Bacillus stearothermophilus TS-23

An amylopullulanase gene (apuTS) from Bacillus stearothermophilus TS-23 was cloned and characterized. apuTS consisted of an open reading frame of 6054 bp encoding a protein of 2018 amino acids with a calculated M(r) of 223811. The deduced amino acid sequence revealed four highly conserved regions that are common among amylolytic enzymes. In the C-terminal region, a six-amino-acid sequence (Pro-Gly-Ser-Gly-Thr-Thr) is repeated nine times. It shared the highest degree of homology with the amylopullulanase of Bacillus sp. XAL601. The enzyme also had moderate homology with amylopullulanases from thermophilic anaerobic bacteria. Low levels of homology were observed between the ApuTS of B. stearothermophilus TS-23 and amylopullulanases of Pyrococcus abyssi Orsay, P. furiosus and Bacillus sp. KSM1378. When the intact coding region of apuTS was expressed in Escherichia coli under the control of the lac promoter, the product was degenerate, as revealed by amylase activity staining after SDS/PAGE. The largest active polypeptide had an M(r) of about 220000, while the smallest one had an M(r) of about 105000. Upstream of the apuTS gene, a gene orfX was fortuitously cloned. The putative OrfX protein was weakly related to the myosin heavy chain. It was predicted to contain a central, 179-residue-long, coiled-coil domain.

Class inequalities in women's health: combined impact of childhood and adult social class--a study of 630 US women

To assess contributions of childhood and adult social class to class gradients in women's health, the authors used gender-neutral household measures of class position in a retrospective cohort study of 630 women enrolled in Examination II of the Kaiser Permanente Women Twins Study (1989-1990, Oakland, CA). The age-adjusted odds of reporting fair or poor health was 2.3 times higher (95% confidence interval (CI)=1.2-4.1), using adult class measures, among women categorized as working class vs non-working class/professional. When stratified by childhood social class, however, the elevated risk of fair/poor health among adult working class compared to non-working class/professional women was evident only among those with a non-working class/professional childhood. Similarly, a working class tendency (based on adult class position) towards elevated levels of low density lipoprotein (LDL) cholesterol (odds ratio (OR)=1.5, 95% CI=0.9-2.7) and post-load glucose (OR=1.8, 95% CI=1.0-3.3) was apparent only among women who were non-working class in childhood. These results indicate that both childhood and adult class position influence class gradients in women's health in the United States.

Single-pulse transcranial magnetic stimulation reset the rhythm of essential tremor but not heart beat

BACKGROUND

Human oscillator is observed in and outside the nervous system. Cardiac rhythm is generated by heart itself but can be modulated by brain. Using the technique of transcranial magnetic stimulation (TMS) and resetting index, we studied if single-pulse TMS could reset the cardiac rhythm and help differentiate oscillator of neurogenic or non-neurogenic origin.

METHODS

In addition to the study of 4 patients with essential tremor, cardiac rhythm was studied in 6 normal subjects. The magnetic intensity was initiated from motor threshold of hand muscle, and then with an increment of 10% up to the maximal output of magnetic stimulator. We used the resetting index (RI) to quantify the influence of the TMS.

RESULTS

The resetting phenomenon was observed in essential tremor (RI = 0.92) but not in cardiac rhythm (RI = 0.02).

CONCLUSIONS

Single-pulse TMS is able to reset the rhythm of essential tremor but not heart beat. The pacing mechanism is different between essential tremor and heart beat. The cardiac rhythm is regulated and modulated chiefly by heart itself. Essential tremor should not share the same mechanism with heart beat.

Vasopressin reverses aluminum-induced impairment of synaptic plasticity in the rat dentate gyrus in vivo

Aluminum (Al), an important neurotoxin, contributes to a variety of cognitive dysfunction and mental diseases. Previous studies have demonstrated that Al impairs hippocampal long-term potentiation (LTP) in vitro and in vivo. In the present study, both LTP and LTD (long-term depression) were recorded in the same animal to investigate the Al-induced impairment of synaptic plasticity. Another aim of the present research was to verify whether the impairment of synaptic plasticity induced by Al could be reversed by vasopressin (VP) treatment. Neonatal Wistar rats were exposed to Al from parturition through adulthood (pre- and post-weaning) by the drinking of 0.3% aluminum chloride (AlCl(3)) solution. The input-output (I/O) function, paired-pulse reaction (PPR), excitatory postsynaptic potential (EPSP) and population spike (PS) amplitude were measured in the dentate gyrus (DG) of adult rats (60-90 days) in response to stimulation applied to the lateral perforant path. The results showed: (1) Al reduced the amplitudes of both EPSP LTP (control: 132+/-7%, n=7; Al-exposed: 115+/-10%, n=8, P<0.05) and PS LTP (control: 242+/-18%, n=7; Al-exposed: 136+/-7%, n=8, P<0.01) significantly. The amplitudes of EPSP LTD (control: 82+/-6%, n=7; Al-exposed: 92+/-7%, n=8, P<0.05) and PS LTD (control: 81+/-4%, n=7; Al-exposed: 98+/-5%, n=8, P<0.05) were also decreased by Al treatment. The Al-induced impairments of PS LTP and PS LTD were more serious than that of EPSP LTP and EPSP LTD. (2) In control rats, VP had an increase in the PS LTP amplitude (control: 242+/-18%, n=7; control+VP: 358+/-23%, n=6, P<0.01), while it had no significant effects on PS LTD (control: 81+/-4%, n=7; control+VP: 76+/-7%, n=6, P>0.05). (3) In Al-exposed rats, VP had a significant increase in the amplitudes of both PS LTP (Al-exposed: 136+/-7%, n=8, Al-exposed+VP: 255+/-16%, n=6, P<0.01) and PS LTD (Al-exposed: 98+/-5%, n=8; Al-exposed+VP: 81+/-6%, n=6, P<0.05). After the application of VP, the range of synaptic plasticity (PS LTP+PS LTD) in Al-exposed rats increased from 38% to 174%, which surpassed that in control rats (161%). It was suggested that VP could reverse Al-induced impairment of synaptic plasticity and might be an effective medicine to cure Al-induced neurological disorders.

The association of human papillomavirus 16/18 infection with lung cancer among nonsmoking Taiwanese women

Lung cancer is the leading cause of cancer death in Taiwanese women since 1982. High lung cancer mortality ratio of male:female in Taiwan (2:1) was observed, although less than 10% of female lung cancer patients are smokers. Until now, the etiological factor remains unknown. We hypothesize that high-risk human papillomavirus (HPV) 16/18 may be associated with lung cancer development based on high prevalence of p53 negative immunostainings in female lung tumors compared with that of male lung tumors. In this study, 141 lung cancer patients and 60 noncancer control subjects were enrolled to examine whether HPV 16/18 DNA existed in lung tumor and normal tissues by nested PCR and in situ hybridization (ISH), respectively. The concordant detection of HPV 16 and 18 DNA between nested PCR and ISH method was 73 and 85.5%, respectively. Our data showed that 77 (54.6%) of 141 lung tumors had HPV 16/18 DNA compared with 16 (26.7%; P = 0.0005) of 60 noncancer control subjects. In addition, ISH data showed that HPV 16/18 DNA was uniformly located in lung tumor cells, but not in the adjacent nontumor cells. When study subjects were stratified by gender, age, and smoking status, nonsmoking female lung cancer patients who were older than 60 years old had significantly high prevalence of HPV 16/18 infection. The odds ratio of HPV 16/18 infection of nonsmoking female lung cancer patients is much higher at 10.12 (95% confidence interval, 3.88-26.38) compared with 1.98 (95% confidence interval, 0.84-4.76) of nonsmoking male lung cancer patients. This result strongly suggests that HPV infection is associated with lung cancer development of nonsmoking female lung cancer patients. The high prevalence of HPV 16/18 infection may explain to a certain extent why Taiwanese women nonsmokers had a higher lung cancer mortality rate.

NEPHROID METAPLASIA OF A GRAFT KIDNEY

BACKGROUND

Nephroid metaplasia is a benign and rare lesion that is confined to the lamina propria of the urinary tract. The leading cause of these lesions is previous trauma to the urothelium.

METHOD

We report a case of nephroid metaplasia of a graft kidney from a living-unrelated donor. This patient presented to our clinics due to painless gross hematuria 1 month after renal transplantation.

RESULT

Although malignancy was suspected in the beginning due to a filling defect demonstrated by urography, only percutaneous excision of the tumor was performed to preserve the renal function. However, the pathological result disclosed nephroid metaplasia.

CONCLUSION

Hematuria warrant aggressive evaluation because underlying malignancy in a immunocompromised patient might be relatively progressive.

Primary renal sarcoma with inferior vena cava thrombus presenting with tumor rupture

Primary renal sarcoma represents approximately one per cent of all primary tumors of the kidney in adults. We report an unusual case of primary renal sarcoma with inferior vena cava (IVC) thrombus. This patient presented with hemorrhagic shock due to tumor rupture. Emergent radical nephrectomy and vena caval thrombectomy were performed. Histological examination proved a clear cell sarcoma.

A new method for true and spurious eigensolutions of arbitrary cavities using the combined Helmholtz exterior integral equation formulation method

Integral equation methods have been widely used to solve interior eigenproblems and exterior acoustic problems (radiation and scattering). It was recently found that the real-part boundary element method (BEM) for the interior problem results in spurious eigensolutions if the singular (UT) or the hypersingular (LM) equation is used alone. The real-part BEM results in spurious solutions for interior problems in a similar way that the singular integral equation (UT method) results in fictitious solutions for the exterior problem. To solve this problem, a Combined Helmholtz Exterior integral Equation Formulation method (CHEEF) is proposed. Based on the CHEEF method, the spurious solutions can be filtered out if additional constraints from the exterior points are chosen carefully. Finally, two examples for the eigensolutions of circular and rectangular cavities are considered. The optimum numbers and proper positions for selecting the points in the exterior domain are analytically studied. Also, numerical experiments were designed to verify the analytical results. It is worth pointing out that the nodal line of radiation mode of a circle can be rotated due to symmetry, while the nodal line of the rectangular is on a fixed position.

Bilateral superior cervical ganglionectomy increases choroidal blood flow in the rabbit

In this study, we evaluate the effect of bilateral superior cervical ganglionectomy on albino rabbit choroidal blood flow (CBF) in changes of perfusion pressure (PP). Twenty albino rabbits of either sex weighing between 2.0 and 3.0 kg were randomly divided into two groups. The experimental group (group S) included 10 rabbits (20 eyes) that received bilateral superior cervical ganglionectomy one week prior to the study. The other 10 rabbits (20 eyes) served as a control (group N): each received the same procedure as group S except that the superior cervical ganglion was preserved. By means of a laser Doppler flowmeter (Perimed PF4001), blood cell flux (PF), velocity (V), and concentration of moving blood cells (CMBC) were recorded simultaneously while intraocular pressure was increased linearly by a syringe pump. Blood pressure and intraocular pressure were continuously monitored. The laser beam focused on the posterior pole away from major retinal vessels. When PP decreased from 75 to 0 mm Hg, in group N, PF, V and CMBC decreased from 100% to 6.94+/-0.91%, 8.41+/-0.87%, and 19.38+/-1.11%; in group S, it was 17.75+/-2.58%, 16.78+/-1.48%, and 34.58+/-4.42%, respectively. Group S poses higher PF, V, and CMBC than group N while PP decreased gradually. These results indicate that the superior cervical ganglion plays a role in CBF regulation. Bilateral sympathectomy led to a higher PF in the group S rabbits, indicating increased CBF. PF, V, and CMBC remained constant until PP <55 mm Hg demonstrated the existence of CBF autoregulation within a limited perfusion range in both groups. This autoregulation did not change after sympathectomy.

p53 mutation is infrequent in clear cell carcinoma of the ovary

OBJECTIVE

p53 gene alteration has been extensively studied in epithelial ovarian cancer. However, its occurrence in clear cell carcinoma, an infrequent histologic subtype of epithelial ovarian cancer, is rarely reported. The aim of this study is to determine the status of p53 gene alteration in this distinct type of ovarian carcinoma.

METHODS

Paraffin blocks of tumors from 38 patients with primary or recurrent ovarian clear cell carcinoma were studied for p53 alteration. All these tumors were subjected to immunohistochemical and molecular analysis. Two monoclonal antibodies (DO-7 and PAb 1801) were used for immunohistochemical staining. Genomic DNAs extracted from paraffin blocks of the 38 tumors were subscribed for a nested polymerase chain reaction/single-strand conformation polymorphism (PCR/SSCP) analysis. Tumors showing band shift on SSCP were further prepared for DNA sequencing to determine the site of mutation.

RESULTS

Overexpression of p53 was observed in only one stage III clear cell carcinoma. However, focal positive p53 staining was noted in another five tumors. Of the six tumors showing positive immunohistochemistry, p53 alterations were noted in four tumors. Three tumors revealed a missense point mutation: two were in exon 7 (TCT(227) --> TTT and GGC(245) --> AGC) and one was in exon 5 (CGC(156) --> CAC). Another tumor revealed a 12-bp deletion in two possible ways: it might involve the last four codons at the 3' end of exon 4 (nucleotides 12,288-12,299) or it might cross over the splice junction between exon 4 and intron 4 (nucleotides 12,290-12,301). The former would result in a predicted protein product of 389 amino acids whereas the latter would cause a frameshift in the gene sequence and would result in a truncated protein.

CONCLUSION

Mutations in p53 appear to be much less frequent in clear cell carcinoma than in other histologic types of epithelial ovarian cancer. We suggest that p53 alterations may not play an important role in the development of clear cell carcinoma.

Loss of p16 and/or pRb protein expression in NSCLC. An immunohistochemical and prognostic study

The disruption of p16/pRb pathway has been reported in several types of human cancer including lung cancer. However, the etiological and prognostic involvement of this pathway remains poorly defined in lung tumorigenesis in Taiwan. Therefore, we investigated the expressions of p16 and pRb in 107 non-small cell lung cancer (NSCLC) patients by immunohistochemical analysis. The associations of altered p16 and pRb expressions with prognosis were also examined. Sixty-four specimens (59.8%) exhibited alteration of p16 and/or pRb expression, with 49.5 and 22.4% of the tumors failing to express p16 and pRb, respectively. However, there was no reciprocally correlated expression of p16 and pRb. Negative p16 and pRb expression did not correlate well with patients' clinicopathological parameters such as age, sex, smoking habit, tumor type, and tumor stage. In addition, negative p16 and pRb expression was not statistically associated with poor prognosis (P=0.10 and P=0.74, respectively). Our results suggested that the disruption of the p16/pRb pathway plays a significant role in NSCLC tumorigenesis whereas it may not have significant importance in the prognostic evaluation of NSCLC in Taiwan.

[Management and treatment of osteoporotic patients at gynecological clinic base]

The importance of diagnosis and management of osteoporosis at out-patient based gynecological clinic was mentioned. For the diagnosis of osteoporosis, assessment of spinal bone mineral density by DEXA system is necessary. This data is useful for the evaluation of treatment and the management of the patient motivation. Hormone replacement therapy is effective for postmenopausal osteoporosis, but in Japan patient acceptance of HRT is still low, and thus gynecologists are required of more effort to get an informed consent of HRT from the patient. As there is a large social demand of improving the quality of life of postmenopausal women, clinic based education of HRT to the postmenopausal women is also necessary for an easy acceptance of HRT in future.

Renal cell carcinoma metastasized to the ureteral stump

A rare case of ureteral stump metastasis 3 months after nephrectomy for a renal cell carcinoma is presented. A 62-year-old female had undergone right radical nephrectomy 3 months earlier because of renal cell carcinoma in our hospital, and she came back due to gross hematuria. Cystoscopy revealed a papillary mass with a vascular pedicle protruding from the right ureteral orifice. Transurethral resection of the bladder tumor over right ureteral orifice was performed and the pathologic result showed clear cell adenocarcinoma, which argued in favor of a metastatic lesion from the previous renal cell carcinoma. Ureterectomy and a bladder cuff excision were then adopted for this patient, but no residual tumor was found over the remaining ureter. Nevertheless, the patient died of cancer 36 months after the event of ureteral stump metastasis.

Benign metastasizing leiomyoma of the lung: a case report

Benign metastasizing leiomyoma (BML) refers to benign pulmonary neoplasm associated with a previous or coincident history of uterine leiomyomata. We report the case of a 56-year-old postmenopausal woman with a 4-year history of multiple benign leiomyomatous lesions in bilateral lungs and the uterus. The tumor cells from the lungs and uterus were focally immunoreactive for HMB-45 antibody and progesterone receptor. Immunoreactivity to HMB-45 is well known in smooth muscle cells of hamartomatous neoplasms, such as angiomyolipoma and lymphangioleiomyomatosis, but has not been reported in BML previously. These features suggest a multifocal hamartomatous histogenesis rather than metastasis in the present case.

An appraisal of liver and portal vein resection for hepatocellular carcinoma with tumor thrombi extending to portal bifurcation

BACKGROUND

The role of surgical resection for hepatocellular carcinoma with tumor thrombi involving the major portal vein is controversial because of a high operative risk and poor prognosis. Previously, a resection was performed only when the tumor thrombi were limited to the first branch of the portal vein without extension to the portal bifurcation.

HYPOTHESIS

Concomitant liver and portal vein resection may be beneficial in patients with hepatocellular carcinoma with tumor thrombi extending to portal bifurcation.

DESIGN

Retrospective review.

SETTING

University hospital, tertiary referral center.

PATIENTS

Among 368 patients with hepatocellular carcinoma who underwent a curative resection, portal vein involvement occurred in 112 patients. Fifteen of the 112 patients underwent a concomitant liver and portal vein resection owing to extension of tumor thrombi to the portal bifurcation (group 1). The remaining 97 patients did not need portal vein resection (group 2).

INTERVENTION

Surgical indications, procedures, and results of pathological examination of resected specimens were assessed in patients in group 1. The clinicopathological characteristics, operative morbidity and mortality, and operative results were compared between the 2 groups.

MAIN OUTCOME MEASURES

Disease-free and actuarial survival rates.

RESULTS

Intramural tumor infiltration was found at the site of thrombi adhesion to the portal vein cuff in 11 of 15 patients in group 1. Owing to patient selection bias, patients in group 1 were significantly younger and had better liver function and greater resected liver weight. The operative time, postoperative hospitalization, operative blood loss, amount of blood transfusion, and operative morbidity and mortality did not differ significantly between the 2 groups. The 5-year disease-free survival rates of groups 1 and 2 were 21.6% and 20.4% (P =.19), respectively, while the actuarial survival rates were 26. 4% and 28.5% (P =.33), respectively.

CONCLUSION

Liver resection with partial resection of the portal vein is justified in selected patients with hepatocellular carcinoma with tumor thrombi extending to portal bifurcation.

The short-term effect of pentoxifylline on rabbit choroidal blood flow

This study evaluates the effect of different doses ofpentoxifylline on rabbit choroidal blood flow (CBF). Sixteen albino rabbits of both sexes, weighing 2.0-3.0 kg, were randomly separated into four groups. The first group of rabbits received 2 ml normal saline injection through the ear vein. They served as the control group (group n). Three different doses of pentoxifylline, 1 mg/kg, 5 mg/kg, and 10 mg/kg, were injected intravenously to groups p1, p5 and p10, respectively. By means of a laser Doppler flowmeter, the blood cell flux (PF), velocity, and the concentration of moving blood cells (CMBC) were recorded simultaneously. The laser probe was advanced through the pars plana and positioned near the retinal surface. The mean arterial pressure was recorded at the same time. There was a significant increase in PF at 1, 5 and 10 min in group p10 rabbits compared with the control group (p=0.0005, 0.0416, and 0.0087, respectively). The velocity increased at 5 min in group p5 rabbits (p=0.0082) and at 1, 5 and 10 min in group p10 rabbits (p=0.0188, 0.0080, and 0.0207, respectively) as compared with the controls. The CMBC decreased after injection of pentoxifylline and reached statistical significance at 5 and 10 min in group p5 rabbits (p=0.0019 and 0.0046, respectively) and at 5 min in group p10 rabbits (p=0.0447). These results show that larger doses of pentoxifylline (10 mg/kg) increased the CBF of rabbits. This effect was achieved primarily by an increase in blood cell velocity.

[Research on improving rice resistance to the pest by B.t. and SBTi genes]

B.t. gene alone or and SBTi gene together were introduced into two elite indica rice varieties grown in South China by bombardment. And 21 independent transgenic lines containing B.t. gene and 4 independent transgenic lines containing B.t. gene and SBTi gene were obtained. Molecular and genetics analysis for R1 plants showed integration of multiple transgenes occurred at one genetic locus. Northern blot result proved B.t. gene expressed in R2 transgenic plants stably. Bioassays using R2 transgenic plants with leaf-folder (Cnaphalocrosis medinalis), indicated that transgenic rice plants are more resistant to the pest than untransformed control plants. And those transgenic plants containing B.t. and SBTi genes showed more resistance compared with those plants containing B.t. gene.

[Cloning of cancer-related genes of Rat6 fibroblasts by using an improved differential display method]

The p53 gene is the most frequently mutated gene identified so far in human cancers. When a mutant p53(135)-val gene was allowed to be over-expressed in Rat6(R6) cells, a high incidence of spontaneous transformation was observed in long-term culture of this cell line(R6 # 13-8). To identify genes involved in cell transformation, parental p53 over-expressing cell, R6 # 13-8, and its spontaneous transformant T2, were analyzed by an improved mRNA differential display technique, which was reproducible, simpler, and was able to clone cDNA longer than 500 bp, and was with less false positives. When 33 10-mer or 12-mer single primers with arbitrary but defined sequence were used for PCR, over 90 discrete cDNAs were obtained from R6 # 13-8 and T2 cells. Three differentially expressed cDNAs were identified, one of them is highly expressed in T2 cells, while the other two, 0.8 kb and 0.9 kb long, are highly expressed in R6 # 13-8 cells. The latter were cloned and confirmed by Northern hybridization. Both cloned fragment were not homologous with any published sequence. Our results suggest that the activation and inactivation of genes are involved in the process of the spontaneous transformation from R6 # 13-8 to T2.

Chromosomal changes and clonality relationship between primary and recurrent hepatocellular carcinoma

BACKGROUND & AIMS

Hepatocellular carcinoma (HCC) is highly malignant and prone to recur after surgical treatment. Differentiation between a true relapse of HCC and a second primary tumor is of clinical importance. However, no convenient method is currently available.

METHODS

Comparative genomic hybridization (CGH) was used to analyze 31 pairs of initial and recurrent HCC samples obtained from patients undergoing 2 consecutive surgeries. The resulting chromosomal aberration profiles were used as genomic fingerprints to determine tumor clonalities and their relationships.

RESULTS

Eleven recurrent tumors with high clonal relationship (CR) values (>0.95) were found to be relapsed HCCs, and 11 tumors with CR values close to 0 were found to be second primary HCCs. The other 9 paired samples had inconclusive CR values between 0.95 and 0.4. Two were confirmed by hepatitis B virus integration and X chromosome inactivation analysis to be de novo cancers (CR values, 0.35 and 0. 23, respectively). Initial HCCs that subsequently relapsed accumulated more chromosomal aberration events than those that developed de novo HCC (mean, 16.1 +/- 4.5 vs. 5.4 +/- 4.8 events; P < 0.01). Also, they more frequently showed gains on chromosome arms 3q, 6p, 8q, and 17q and losses on 4q and 16p.

CONCLUSIONS

CGH is useful for chromosomal aberration study and tumor clonality analysis. More and characteristic genomic changes in the initial HCC suggest that subsequent tumor recurrence is a true relapse.

Modulation of symptomatic palatal tremor by magnetic stimulation of the motor cortex

OBJECTIVES

Magnetic stimulation of the motor cortex can be used to determine the involvement of the cortex in rhythmic movement disorders. Symptomatic palatal tremor (SPT) is thought to come from a pacemaker that is relatively resistant to internal and external stimulation. In this study, we investigated the effect of magnetic stimulation of motor cortex on SPT.

METHODS

Five male patients, aged 67-79 years, with SPT after brain stem infarction or hemorrhage, all had a synchronous mouth angle twitch with the palatal movement. Electromyographic activity was recorded with a monopolar needle electrode from orbicularis oris. In experiment 1, transcranial magnetic stimulation (TMS) was delivered at 200% motor threshold (MT) to reset SPT. In experiment 2, the effect of TMS intensities was studied at 80-240% MT in two SPT patients. To determine the influence of the TMS, we used the resetting index (RI).

RESULTS

TMS reset the tremor in all 5 SPT patients at 200% MT with RIs of 0.86-0.96. The latency of the tremor reappearance after TMS was longer than the pre-stimulus tremor interval, and the intervals between the subsequent tremor bursts were also prolonged. The degree of tremor resetting was closely correlated with the magnetic stimulus intensity and the latency of the tremor reappearance after TMS.

CONCLUSIONS

Stimulation of the motor cortex may modulate the generator of SPT.

Frequent down-regulation and lack of mutation of the KAI1 metastasis suppressor gene in epithelial ovarian carcinoma

OBJECTIVE

KAI1 is a recently identified metastasis suppressor gene on human chromosome 11p11.2. It belongs to a structurally distinct family of cell surface glycoproteins. Decreased KAI1 expression seems to be involved in the progression of human prostate, lung, pancreatic, and possibly breast cancer, and recently a reduced KAI1 protein expression has been demonstrated in several ovarian carcinoma cell lines. The aim of this study is to determine whether the KAI1 gene is altered in human epithelial ovarian carcinomas. In addition, its prognostic significance in this tumor is also evaluated.

METHODS

To detect KAI1 expression, 102 tumor samples from benign, borderline, primary invasive, metastatic, and recurrent epithelial ovarian tumors were prepared for immunohistochemical study with C-16, an anti-KAI1 polyclonal antibody. In addition, cellular RNA from 24 primary invasive and 7 recurrent tumors was also analyzed for KAI1 expression by using a reverse transcriptase PCR (RT-PCR) technique. The PCR single-strand conformation polymorphism method and direct DNA sequencing were used to detect KAI1 mutation in the 44 primary invasive and 8 recurrent ovarian carcinomas.

RESULTS

In immunohistochemical study, decrease of KAI1 protein expression was associated with the progression of ovarian tumor. However, it had no relation to the stage of primary invasive cancers because of its frequent occurrence in early stage tumors. KAI1 expression was also frequently down-regulated in primary invasive and recurrent tumors in RT-PCR analysis. Except for a missense change at codon 241 (ATC to GTC), which causes the substitution of a valine for an isoleucine in the amino acid sequence and occurs in both normal and tumor tissues, no mutation of the KAI1 gene was found in any of the 52 carcinomas. Although there was a trend for deteriorating survival from patients with KAI1-preserved tumors to those with KAI1-decreased and -negative tumors, statistically it was not significant (P = 0.079).

CONCLUSION

KAI1 may play a role in the malignant progression of epithelial ovarian carcinoma through the down-regulation of expression rather than gene mutation. Since the decreased expression presented frequently in early stage tumors, it may be an early event in the progression of this tumor and its prognostic significance needs further investigation with a larger number of cases.

Effects of chronic lead exposure on short-term and long-term depression in area CA1 of the rat hippocampus in vivo

Chronic developmental lead (Pb) exposure to the rat has been reported to impair the long-term potentiation (LTP) in area CA1 and DG of the hippocampus. The present study was performed to investigate the effects of chronic Pb exposure on homosynaptic short-term depression (STD) and long-term depression (LTD) of population spikes (PS) in area CA1 of the rat hippocampus in vivo. Neonatal Wistar rats were exposed to Pb from parturition to weaning via the milk of dams fed with 0.2% lead acetate solution. The input/output (I/O) function, paired-pulse reaction (PPR), the PS were measured in the area CA1 in response to low frequency stimulation (LFS). The results showed that the homo-STD amplitude of PS depotentiation in Pb-exposed rats (87.48 +/- 7.44%, n = 14) was less significant than that in control rats (72.34 +/- 6.05%, n = 18, P<0.05), and the homo-LTD amplitude of PS depotentiation in Pb-exposed rats (72.80 +/- 5.86%, n = 14) was even less significant than that in control rats (47.80 +/- 5.03%, n = 18, P<0.01). The results suggest that chronic Pb exposure in neonatal rats caused impairments in the STD and LTD of area CA1 of hippocampus.