Scanning laser polarimetry in evaluation of retinal nerve fiber layer thickness for normal Taiwanese

Scanning laser polarimetry has been used recently for the measurement of retinal nerve fiber layer (RNFL) thickness, taking advantage of the birefrigence of the RNFL. We observe the RNFL with the instrument and try to find out a set of normal basic values of the RNFL thickness for clinical comparison. One hundred normal volunteers of different age groups were recruited for this study. There are 44 males and 56 females with a mean (1SD) age of 36.17(14.77) years. Three consecutive 15-degree polarimetric maps were acquired for each subject. RNFL thickness measurements were obtained at 1.75 disc diameters ring from the optic nerve. Four 90-degree quadrants were identified. As a result, the average of RNFL thickness is 90.69 (20.20) microns in the superior quadrant, 80.45 (17.4) microns in the inferior quadrant, 59.28 (15.37) microns in the nasal quadrant, and 48.98 (15.72) microns in the temporal quadrant with a mean thickness value of 69.86 (13.97) microns. Superior and inferior quadrants showed a comparatively thicker nerve fiber layer than nasal and temporal quadrants. The temporal quadrant was always the lowest. The axial length does not affect the RNFL thickness and no significant difference between males and females exists. However, an obvious inverse linear correlation between age and the RNFL thickness in all quadrants is found. The average RNFL thickness decreased with age by 0.26 micron per year. (R2 = 0.081, p-value = 0.004). When compared with the normal range, age-match would be necessary.

Angiogenically active vascular endothelial growth factor is over-expressed in malignant human and rat prostate carcinoma cells

Vascular endothelial growth factor (VEGF) is one of the most potent factors for stimulating angiogenesis, an essential process required for expansion of primary tumour and dissemination of malignant cells. To investigate the possible role of VEGF in facilitating metastasis of prostate cancer via stimulating angiogenesis, we have used Northern and slot blotting, reverse transcription polymerase chain reaction, nucleotide sequence analysis and enzyme-linked immunosorbent assay to compare the VEGF expression in series of human and rat cell lines with either benign or malignant characteristics. We have also employed the chick chorioallantoic membrane (CAM) assay to measure the angiogenic activity of the VEGF derived from both benign and malignant cells. The level of VEGF mRNA expressed in the seven malignant human and rat cell lines is 3.5- to 10-fold higher than that expressed in the benign cell lines. The three metastatic variants, generated by transfection of a benign cell line with DNA extracted from prostate carcinoma cells, expressed 2.5 to 5 times more VEGF mRNA than their parental benign cells. While VEGF 121 and 165 were predominantly expressed by both the benign and malignant cells, the transcript representing VEGF 189 isoform was only detected in the malignant cells. At protein level, three human malignant cell lines produced more VEGF (2.7-7.9 ng ml(-1)) than the benign cell line (1.3 ng ml(-1)). CAM assay detected a VEGF-dependent angiogenic activity in the medium from malignant cells, but only a relatively weak VEGF-independent activity in the medium from benign cells. These results demonstrated that malignant cells did over-express VEGF and only the VEGF derived from malignant cells was angiogenically active. Thus, we suggest that the VEGF produced by malignant cells might play an important role in facilitating metastasis of prostatic cancer.

Degradation of DNA topoisomerase I by a novel trypsin-like serine protease in proliferating human T lymphocytes

DNA topoisomerase I (Topo I) contributes to various important biological functions, and its activity is therefore likely regulated in response to different physiological conditions. Increases in both the synthesis and degradation of Topo I were previously shown to accompany phytohemagglutinin stimulation of proliferation in human peripheral T lymphocytes. The mechanism of this degradation of Topo I has now been investigated with both in vivo and in vitro assays. The activity of a nuclear protease that specifically degrades Topo I was induced in proliferating T lymphocytes. The full-length Topo I protein (100 kDa) was sequentially degraded to 97- and 82-kDa fragments both in vivo and in vitro. The initial site of proteolytic cleavage was mapped to the NH(2)-terminal region of the enzyme. The degradation of Topo I in vitro was inhibited by aprotinin or soybean trypsin inhibitor, suggesting that the enzyme responsible is a trypsin-like serine protease. Furthermore, Topo I degradation by this protease was Mg(2+)-dependent. The Topo I-specific protease activity induced during T lymphocytes proliferation was not detected in Jurkat (human T cell leukemia) cells and various other tested human cancer cell lines, possibly explaining why the abundance of Topo I is increased in tumor cells.

Transcriptional repression of p21((Waf1/Cip1/Sdi1)) gene by c-jun through Sp1 site

Previously, we found that c-jun represses the tumor suppressor p21((Waf1/Cip1/Sdi1)) (p21) gene expression. In this study, we further investigated the mechanism of the inhibitory effect of c-jun on p21. After analysis of a series of deletion and point mutants of p21 promoter, we found that Sp1-3 site (-77 and -83) relative to the transcription start site played an important role for c-jun-repressing-responsive element in the p21 promoter. Both Sp1 and Sp3 transcription factors were the key factors for this event. However, the data from electrophoretic mobility shift assay indicated that c-jun did not change the Sp1 DNA-binding affinity, suggesting that additional factors may be involved in the repression of p21 by c-jun. Furthermore, c-jun could inhibit butyrate-inducing p21 gene expression through Sp1, indicating at least one common pathway whereby p21 expression is affected by c-jun and butyrate in opposing actions. Moreover, the hyperphosphorylated retinoblastoma protein (Rb) increased in c-jun expressing cells, indicating that phosphorylated Rb may play a role in regulating Sp1 to repress p21 expression. This is the first demonstration of how housekeeping factors and oncogene product counteract the function of tumor suppressor genes to control cell cycle progression.

Atopic cataracts in a child with atopic dermatitis: a case report and review of the literature

Cataracts induced by atopic dermatitis rarely occur in adolescent and young adult patients suffering from this problem. Lenticular opacity is an important ocular complication in atopic dermatitis. Although the cause of atopic dermatitis and its ocular complications are unknown, cataracts have been observed to develop and progress during periods of exacerbation of the dermatitis. We report the case of a 16-year-old boy with atopic dermatitis who abruptly developed cataracts in both eyes while suffering from severe skin itching which began 2 months before the initial examination. His peroxidation test result was very high, and we postulate the retinal peroxidation might play a key role in cataractogenesis. Lens aspiration and intraocular artificial lens implantation were performed smoothly with restoration of visual acuity in both eyes.

Ptosis surgery on chronic myasthenia gravis

We report three cases of long-standing, early onset myasthenia gravis. The eyes of all three patients eventually became disabled, and the patients were almost unable to move their eyes in any direction. We termed this condition as "frozen eyes" appearance. We discuss the unique clinical condition and follow the electromyographic and neuro-ophthalmological characteristics. The patients all suffered from ptosis, mild to moderate exotropia, and facial and oropharyngeal weakness. All of the patients responded to the neostigmine test positively at the early stage. Two of them were seropositive. The results of electromyography for two of these three cases were abnormal. The average duration of follow-up was 5 years. The treatments included conventional recession and resection procedures with adjustable sutures for strabismus and frontalis suspension for blepharoptosis. The patients achieved stable satisfactory results in over one-and-a-half years of postoperative follow up.

Changes of bilateral palmar skin temperature in transthoracic endoscopic T-2 sympathectomy

OBJECT

Transthoracic endoscopic T-2 sympathectomy is currently the treatment of choice for palmar hyperhidrosis (PH). Intraoperative monitoring of palmar skin temperature (PST) is often used to assess the adequacy of sympathetic ablation. The aim of this study was to investigate the time course of PST changes during the operation and to determine factors involved in the sympathetic modulation of the palmar skin blood flow.

METHODS

Eighty-one patients with PH underwent bilateral transthoracic endoscopic sympathectomy of T-2 in which continuous intraoperative PST monitoring was used. Palmar skin temperature data, recorded every 30 seconds throughout the operation, were plotted against time, and a graph of two PST curves was obtained in each case. A multiphasic curve pattern of great similarity was observed in nearly 70% of cases. Specific PST readings at different operative stages were collected and averaged for all cases. The trend of PST changes in response to different procedures during the operation was analyzed. It was found that unilateral procedures caused simultaneous bilateral PST alterations. In almost all cases, bilateral PST was dramatically lowered when unilateral skin incision and intercostal muscle dissection were performed. The temperature remained low until the T-2 sympathectomy was finished on one side. In addition, unilateral T-2 sympathectomy induced synchronous elevation of bilateral PST. However, the ipsilateral response was significantly stronger than that on the contralateral side.

CONCLUSIONS

Although intraoperative monitoring of PST is a reliable guide for surgeons performing endoscopic transthoracic sympathectomy, it is important to realize that PST fluctuates at different stages during the operation and that surgical procedures themselves can significantly influence PST readings. The PST data recorded at specific time points, therefore, can be misleading in terms of accuracy and the completeness of ablation of the target sympathetic ganglia, especially when the sympathetic trunk or ganglia are anatomically aberrant.

Favorable clinical outcome of cervical cancers infected with human papilloma virus type 58 and related types

To determine whether the status of human-papillomavirus (HPV) infection affects the clinical outcome of cervical carcinoma (CC), HPV genotype was prospectively determined in 94 consecutive CC cases subsequently followed for a median duration of 37.5 months. With a consensus PCR-RFLP method of HPV genotyping, 81 (86.2%) cancers were positive for HPV DNA. They were classified, according to the phylogenic similarities, into HPV-16-related (type 16, n = 45; type 31, n = 2), HPV-58-related (type 58, n = 17; type 33, n = 3; type 52, n = 2) and HPV-18-related (type 18, n = 8; type 68, n = 1) groups, and analyzed in relation to clinical outcome. The following results were observed: (i) Type-58-related HPVs were more prevalent in the old age (older than the median age of 52) group than in the young age group (41% vs. 14.6%, p = 0.045); (ii) 63% (5/8) of patients with advanced stages (III and IV) were HPV-negative, a figure much higher than that (9.3%, 8/84) of patients with early stages (stage I and II) (p = 0.002); (iii) the occurrence of adenocarcinoma or adenosquamous carcinoma was higher in the HPV-18-related group (50%) than in the HPV-16-related (33.3%) or the HPV-58-related (16.7%) groups (p = 0.024); (iv) the status of lymph-node metastasis and tumor grade did not correlate with HPV status; (v) 5-year survival rates were 90.2%, 80% and 74% for HPV-58-, HPV-16- and HPV-18-related groups, respectively (p = 0.03, after adjustment for tumor stage); (vi) in comparison with the HPV-16-related group, the relative risk of death in the HPV-58- and the HPV-18-related groups were 0.32 [95% CI, 0.07-1.49] and 1.87 [0.36-14.9] respectively. HPV genotype appears to affect the clinical behavior and outcome of cervical cancer. HPV-58-related types are prevalent in the older population, and appear to confer a favorable prognosis. Int. J. Cancer (Pred. Oncol.) 84:553-557, 1999.

Detection and quantification of 1,N(6)-ethenoadenine in human placental DNA by mass spectrometry

Exocyclic DNA adducts have been reported to derive from various exogenous as well as endogenous sources, such as lipid peroxidation. Among them, 1,N(6)-ethenoadenine (epsilonAde) has previously been detected in tissue DNA of untreated rodents and humans by an immunoaffinity/(32)P-postlabeling method. This study reports detection and quantification of the endogenous epsilonAde adduct in the same human placental DNA by three independent assays, namely, GC/MS, LC/MS, and HPLC/fluorescence. Using a recently reported gas chromatography/negative ion chemical ionization/mass spectrometry (GC/NICI/MS) method [Chen, H.-J. C., et al. (1998) Chem. Res. Toxicol. 11, 1474], the level of epsilonAde in human placental DNA from a commercial source was found to be 2.3 adducts per 10(6) Ade bases. To confirm these findings, a liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI/MS/MS) method was developed for epsilondAdo. With this LC/MS assay, epsilondAdo was detected at the level of 2.5 adducts per 10(6) dAdo nucleosides in the same human placental DNA. The stable isotopes of epsilonAde and epsilondAdo were added as internal standards in both GC/MS and LC/ESI/MS/MS assays, respectively, and thus provided high specificity, reproducibility, and accurate quantification. The relatively high levels of epsilonAde in this human placental DNA detected by mass spectrometry were further verified by HPLC/fluorescence analysis. The GC/MS method was validated by the HPLC/fluorescence assay using calf thymus DNA treated with chloroacetaldehyde or by the LC/MS method with 2, 3-epoxy-4-hydroxynonanal-modified calf thymus DNA. The epsilonAde level in human placental DNA freshly isolated in the presence of an antioxidant was similar to that in DNA from the commercial source. Since epsilonAde is a potential mutagenic lesion, analysis of epsilonAde by the specific and sensitive GC/NICI/MS method may provide a useful biomarker in cancer risk assessment.

Porous balloon delivery of S-dC28 does not prevent restenosis in the porcine coronary artery model of balloon injury

Phosphorothioate (PS) oligodeoxynucleotides (ODN) inhibit vascular smooth muscle cell proliferation through antisense and G-quartet aptameric mechanisms. PS-ODN such as the cytidine homopolymers, have been demonstrated to have non-G-quartet, nonsequence-specific inhibitory effects in a rat carotid balloon injury model of neointimal proliferation. We sought to test the efficacy of S-dC28, a cytidine homopolymer lacking G-quartets, on neointimal proliferation in the porcine coronary artery model of balloon injury. A total of 23 animals (11 controls, 12 treated) were subjected to balloon injury in a coronary artery, followed by infusion of control solution or S-dC28 via porous balloon, the Scimed Dispatch Coronary Infusion Catheter. After a mean interval of 49 days, the animals were killed, and the target coronary segments were examined histologically. S-dC28 did not significantly inhibit neointimal formation. Fluorescein isothiocyanate (FITC)-labeled S-dC28 was present in the intima and media immediately after administration but was present mainly within the adventitia 3 hours after administration. S-dC28, when delivered by a Scimed Dispatch Coronary Infusion Catheter (Maple Grove, MN), did not significantly affect neointimal proliferation after balloon injury in a porcine coronary artery model.

Aerodynamic measurements of patients with Parkinson's disease

Patients with Parkinson's disease commonly complain of voice dysfunction. Most of these complaints can be attributed to the known muscular control disorders that occur with Parkinson's disease. However, the manifestations of Parkinson's disease muscular dysfunction on parameters of phonation such as airflow, laryngeal resistance, and subglottal pressure necessary to sustain phonation have not been reported. The purpose of this study was to examine the aerodynamic characteristics of flow, laryngeal resistance, and phonation pressure threshold in a heterogeneous population of patients with Parkinson's disease who had varying voice complaints and to compare the data to similar studies for human subjects who have no voice complaints. The studies used a noninvasive method of detecting flow and acoustic signal from the lips, oral cavity and nose during phonation and used an external flow interruption technique to estimate subglottal pressure and phonation threshold pressure. About one third of the patients could not produce phonation at regular and loud intensities that were comfortable for normal subjects. The mean subglottal pressure (SGP) of patients with Parkinson disease who could produce 3 levels of intensity comparable to normal subjects was significantly higher than the mean SGPs for normal subjects for the same intensities of vocal production. The mean flow rates measured from patients with Parkinson's disease at the same 3 intensities of phonation was not significantly greater than in normal subjects. This indicated that the mean laryngeal resistance calculated for patients with Parkinson's disease was notably and significantly greater than mean laryngeal resistance calculated for normal subjects at the same intensity levels. The mean vocal efficiency (VE) for normal subjects was not significantly different than the mean VE for patients with Parkinson's disease, because greater pressure was used to generate similar flow and acoustic energy. These findings correlate with the perception of patients with Parkinson's disease that they are working harder to produce phonation. The observation of notably greater laryngeal resistance and phonation threshold pressure in patients with Parkinson's disease suggests that further studies of the glottic aperture in patients with Parkinson' disease may be useful for understanding how this common motor disorder disturbs phonation.

Development of a prefabricated treatment plant for diluted pig wastewater

In order to develop a prefabricated treatment and reuse plant for diluted pig wastewater, an entrapped-mixed-microbial-cell (EMMC) process was evaluated for its process performance and economic analysis. At the hydraulic retention time (HRT) of 30 hrs (loading rate of 1.0 g TCOD/L/d) and intermittent aeration of 1 hr of aeration and 1 hr of non-aeration, it was found that, by using the pretreatment of the ammonium crystallization, both the medium and large carriers were able to reduce TCOD, SCOD, and T-N by 83.51, 84.11, and 95.10%, respectively. The EMMC unit and lime post-treatment followed by ammonium crystallization can reduce BOD5, TCOD, SCOD, TSS, T-N, and T-P, respectively by 99.22, 93.85, 92.67, 97.73, 96.43, and 97.27%. The treated wastewater, after disinfection, is able to meet the requirements of the standards issued by the USEPA for reuse of food crops. The economic analysis indicates that based on the process performance of the EMMC unit, a prefabricated wastewater treatment plant for 2000 pigs has comparable net present worth (NPW) comparing intermittent aerated biological systems and less operation and maintenance and land requirement than conventional biological processes for removal carbon and nitrogen. A farm operation of more than 2000 pigs meets the unit cost of US$4.91/pig/yr. This will minimize the problems pertaining to technical factors or considerations that heavily influence planning, construction and operation of a pig wastewater treatment system.

Binding of ATP to human DNA topoisomerase I resulting in an alteration of the conformation of the enzyme

It has been known for some time that ATP inhibits the DNA relaxation activity of human DNA topoisomerase I. However, the underlying mechanism of this inhibitory effect remains largely unknown. Using filter binding assays, the binding of human DNA topoisomerase I to DNA was decreased in the presence of ATP. This result suggests that the inhibition of DNA relaxation activity of human DNA topoisomerase I by ATP is at the binding step rather than at the nicking or resealing step. DNA topoisomerase I cleavage assay further supports this notion. ATP-agarose binding and UV cross-linking assays also demonstrate that ATP directly and specifically binds human DNA topoisomerase I. To address whether the ATP binding results in conformational changes in human DNA topoisomerase I, various proteases were employed for detecting potential protein conformational changes. Our results indicated that the proteolytic susceptibilities of trypsin and chymotrypsin were altered in the presence of ATP. The result suggests that the conformation of human DNA topoisomerase I was altered upon ATP binding. In addition, the binding between ATP and human DNA topoisomerase I was also reduced by increasing concentrations of DNA. Our data suggests that human DNA topoisomerase I exhibits at least two incompatible conformations. One conformation is in the form of a topoisomerase I-ATP complex, which inhibits DNA relaxation activity of human DNA topoisomerase I, and the other, a topoisomerase I-DNA complex, which exerts DNA relaxation activity. Our studies identify the role of ATP in the regulation of human DNA topoisomerase I and provide a substantial implication of how human DNA topoisomerase I compromises its versatile functions.

Neuroimages of disseminated neurotuberculosis: report of one case

We report a 38-year-old male patient with rare concurrent intracranial and intramedullary tuberculoma demonstrated by serial magnetic resonance image (MRI) and confirmed by a pathological study. The involvement of the middle cerebral artery is also shown by magnetic resonance angiography. These findings have a good correlation with the clinical features including cranial nerve involvement, stroke-like symptoms, and paraplegia.

Mechanisms of Surface Precipitation and Dissolution of Barite: A Morphology Approach

Barite (BaSO4) was synthesized at normal pressure and room temperature by mixing sodium sulfate and barium chloride solutions by gentle flow (0.5 ml/min.). The well-formed rectangular and rhombohedral crystals with smooth faces formed from solutions with low degrees of supersaturation. Most precipitates became single crystals. We employed the scanning electron microscope (SEM) to observe barite dissolution by chemical agent diethylenetrinitrilopentaacetic acid. Molecular modeling was used to assist the interpretation of the surface reaction. A kinetic model for the pit growth (initial dissolution) on the surface was evaluated. With SEM microanalysis of barite and kinetic model of pit growth, important surface phenomena and mechanisms of dissolution can be hypothesized. Surface phenomena and composition are very important in barite dissolution. Experimental results suggest that the initial dissolution starts on the two lowest energy surfaces: (001) and (210), and that the etch pits are elongated in one direction on the (210) surface and formed cavities on the (001) surface. The simulated surface structures by molecular modeling can aid the interpretation the pit formation on those selected surfaces. Copyright 1999 Academic Press.

Cerebral sparganosis: case report

A 19-year-old man visited our hospital following an attack of general tonic-clonic convulsion. Multiple lesions were noted over bilateral frontal areas on brain computed tomography and magnetic resonance images. The diagnosis was confirmed by positive antibody for sparganum using enzyme-linked immunosorbent assay (ELISA). Praziquantel, 2400 mg/d for one month, was prescribed before the antibody test results came out and the treatment failed. Total removal of the lesion and the enclosed parasite cured the patient. Although the features of cerebral sparganosis on brain computed tomography and magnetic resonance images have been previously described, the findings were not specific and the present case exhibited some different patterns including bilateral multiple calcifications and ventricular compression. The significance of the bilateral involvement is not known but the ventricular compression suggests that the disease was in an active stage. Imaging studies appear to only provide some clues for the diagnosis of sparganosis. Bilateral involvement may be seen as in the present case. The final diagnosis depends on pathologic or immunologic examination results. Surgical intervention either using stereotactic techniques or total removal of the lesion is the treatment of choice while antiparasitic agents are ineffective.

Inhibition of DNA synthesis by downregulation of cyclin A but not Skp 2 overexpression in human hepatocellular carcinoma cells

Cyclin A is an S and G2/M phase regulatory protein and associates with Skp 2 in many transformed cells. Our previous results showed that 12 (39%) and 17 (55%) out of 31 hepatocellular carcinoma (HCC) patients exhibited higher protein expression levels of cyclin A and Skp 2, respectively, in their tumorous compared to non-tumorous tissues. In the present study, we used Western blot analysis to show that 3 out of 6 HCC cell lines, HA59T, HA22T and HCC36, exhibited overexpression of cyclin A, among which the HCC36 cell line also expressed a higher Skp 2 protein level. Moreover, we used the antisense oligonucleotide phosphorothioates to down regulate the overexpression of cyclin A and Skp 2 proteins to determine whether or not these two proteins are involved in the mitogenesis of HCC36 cells. After treatment with antisense oligonucleotide phosphorothioates, the gene product of cyclin A or Skp 2 was suppressed dose-dependently as revealed by Western blot analyses. By [3H]thymidine incorporation assay, we found that downregulation of cyclin A but not Skp 2 overexpression could inhibit the DNA synthesis ability of HCC36 cells, suggesting that abnormal Skp 2 expression is not directly correlated with the HCC proliferation.

Dioscorin, the major tuber storage protein of yam (Dioscorea batatas decne) with carbonic anhydrase and trypsin inhibitor activities

Dioscorin, the tuber storage protein of yam (Dioscorea batatas Decne), was purified successively by ammonium sulfate fractionation, DE-52 ion exchange chromatography, and Sephadex G-75 column. Two protein bands (82 and 28 kDa) were found under nonreducing conditions after SDS-PAGE; but only one band (32 kDa) was detected under reducing conditions. The first 21 amino acids in the N-terminal region of the 28 kDa form were VEDEFSYIEGNPNGPENWGNL, which was highly homologous to deductive sequence of dioscorin from cDNA of another yam species (Dioscoreacayenensis Lam) reported by Conlan et al. (Plant Mol. Biol. 1995, 28, 369-380). Hewett-Emmett and Tashian (Mol. Phylogenet. Evol. 1996, 5, 50 -77) mentioned that, according to DNA alignments, dioscorin from yam (D. cayenensis) was alpha-carbonic anhydrase (alpha-CA) related. In this report, we found that the purified dioscorin showed both CA dehydration activity using sodium bicarbonate as a substrate and CA activity staining after SDS-PAGE. A polyclonal antibody, which was raised against trypsin inhibitor (TI), a storage protein of sweet potato (Ipomoea batatas [L.] Lam var. Tainong 57), cross-reacted with dioscorin, which also showed TI activity determined by both activity staining after SDS-PAGE and trypsin inhibition determination.

Detection of protease activities using specific aminoacyl or peptidyl p-nitroanilides after sodium dodecyl sulfate - polyacrylamide gel electrophoresis and its applications

A general method for detecting protease activities on acrylamide or agarose gels after sodium dodecyl sulfate - polyacrylamide gel electrophoresis (SDS-PAGE) using specific aminoacyl p-nitroanilide (NA) or peptidyl NA as substrate is described. This method is extended from the spectrophotometric assay of p-nitroaniline, which is a chromogenic product liberated by protease action on aminoacyl NA or peptidyl NA. The acrylamide gel containing protein bands was dipped directly into a solution which contained specific synthetic aminoacyl NA or peptidyl NA as a substrate or had been overlaid with an agarose gel containing the same substrate. The p-nitroaniline released on the acrylamide or agarose gel by the specific protease was diazotized with sodium nitrite and then coupled to N-(1-naphthyl)-ethylenediamine to produce distinct activity band(s). The substrates used for protease activity staining on gels were identical to those used for spectrophotometric assays. Some applications are described.

Management of choroidal melanomas with linear accelerator-based stereotactic radiosurgery

PURPOSE

To discuss the technical aspect, dose prescription, clinical results, and biological responsiveness of linear accelerator-based stereotactic radiosurgery for choroidal melanoma.

METHODS

From March 1995 to December 1995, three choroidal melanoma patients were treated with Linac-based radiosurgery in our department. Two patients underwent one dose of radiosurgery with 18 and 20 Gy in single fraction, respectively. The third patient received two doses of radiosurgery with a total dose of 35 Gy.

RESULTS

Follow-up time ranged from 19 to 25 months (median: 24 months). One patient had near-total regression, while the other two patients had partial response on the last MR images. Visual acuity was deteriorated in all patients. One patient developed a radiation-induced cataract in the treated eye.

CONCLUSION

Linac-based radiosurgery is technically feasible for management of choroidal melanoma. Although visual acuity was not improved in these patients, they appreciated the preserving of the eyeball without affecting their general appearance.

Closed reduction of bilateral locked facets of the cervical spine under general anaesthesia

BACKGROUND

Bilateral facet interlocking of the cervical spine is a relatively uncommon type of cervical spinal injury. It is frequently associated with devastating neurological symptoms and signs. Early reduction of the locked facets is thought to be critical in preventing progressive secondary spinal cord injury. Whereas skull tong traction remains our primary option for closed reduction of bilateral locked facets of the cervical spine, it is not always successful, even with heavy traction weights. Other more aggressive measures may occasionally be required. The authors report their experience in reducing bilateral locked facets of the cervical spine by manual closed reduction.

METHODS

This small series consists of six cases of cervical spinal injury with bilateral locked facets in which manual closed reduction under general anaethesia and muscle relaxation was used. Three of them presented with complete quadriplegia (Frankel class A). One case presented with incomplete but severe neurological deficits (Frankel class B). After unsuccessful closed reduction with skull traction, these patients were treated by manual closed reduction under general anaesthesia and muscle relaxation, followed by anterior discectomy, interbody fusion and stabilization.

RESULTS

All cases made neurological improvement after the procedures. Even in cases with initial severe neurological deficits, the recovery was remarkable. The recovery was dramatic in two cases. Case 1 improved from Frankel class B to E; and Case 5 from Frankel class A to D. No case deteriorated neurologically after the procedures. Pneumonia occurred in Case 3; and stress ulcer accompanied by haemorrhage was noted in Case 4. None of these complications was directly related to the procedures.

CONCLUSION

The potential for improvement of neurological function following early and successful reduction and fixation of the dislocated spine is emphasized. With meticulous techniques, manual closed reduction may be an effective alternative to skull tong traction when the latter fails.

DNA adducts of 2,3-epoxy-4-hydroxynonanal: detection of 7-(1', 2'-dihydroxyheptyl)-3H-imidazo[2,1-i]purine and 1,N6-ethenoadenine by gas chromatography/negative ion chemical ionization/mass spectrometry

2,3-Epoxy-4-hydroxynonanal (EH) is a bifunctional aldehyde formed by epoxidation of trans-4-hydroxy-2-nonenal, a peroxidation product of omega-6 polyunsaturated fatty acids. EH is mutagenic and tumorigenic and capable of modifying DNA bases forming etheno adducts in vitro. Recent studies showed that etheno adducts are present in tissue DNA of humans and untreated rodents, suggesting a potential endogenous role of EH in their formation. A sensitive assay is needed so we can determine whether EH is involved in etheno adduct formation in vivo and study the biological significance of the etheno adducts in DNA. In this study, we developed a gas chromatography/negative ion chemical ionization/mass spectrometry assay for the analysis of 1, N6-ethenoadenine (epsilonAde) and 7-(1', 2'-dihydroxyheptyl)-3H-imidazo[2,1-i]purine (DHH-epsilonAde) in DNA; both are products from the reaction of adenine with EH. The assay entails the following sequence of steps: (1) addition of [15N5]epsilonAde and [15N5]DHH-epsilonAde to DNA as internal standards, (2) acid hydrolysis of DNA, (3) adduct enrichment by C18 solid phase extraction (SPE), (4) derivatization by pentafluorobenzylation (PFB), (5) separation of PFB-epsilonAde and PFB-DHH-epsilonAde on a Si SPE column, (6) acetonide (ACT) formation of PFB-DHH-epsilonAde, and (7) GC/MS analysis with selective ion monitoring (SIM). The limit of detection by on-column injection for PFB-epsilonAde monitoring of the (M - PFB)- ion at m/z 158 was 30 amol and for ACT-PFB-DHH-epsilonAde monitoring of the (M - PFB)- ion at m/z 328 was 0.4 fmol; the detection limits for the entire assay were 6.3 fmol for epsilonAde and 36 fmol for DHH-epsilonAde. In calf thymus DNA modified with EH at 37 degreesC for 50 h, both epsilonAde and DHH-epsilonAde were detected at high levels by this method, 4.5 +/- 0.7 and 90.8 +/- 8.7 adducts/10(3) adenine, respectively. These levels were also verified by HPLC fluorescence analysis, indicating that EH extensively reacts with adenine in DNA, forming etheno adducts. The high sensitivity of the assay suggests that it may be used in the analysis of ethenoadenine adducts in vivo.

Molecular characterization of germline mutations in neurofibromatosis 2 in two families

Neurofibromatosis 2 (NF2) is an autosomal dominant disorder that predisposes patients to central nervous system tumors. It is caused by mutations in the NF2 tumor suppressor gene, which is located on chromosome 22q12. We studied 2 multigenerational NF2 families (three members of family 1 and the proband of the family) by gene mutation analysis and clinical assessment. One member of family 1 had a 169 C-->T point mutation at codon 57 of exon 2 and had a severe phenotype. His father had a silent 1113 C-->T point mutation at codon 371 of exon 11 and had a normal phenotype. The proband of family 2 had a deletion at nucleotide 720 G (codon 240) of exon 8. This led to a frameshift and termination at codon 250, and a severe NF2 phenotype. Our results indicate that clinical abnormalities can be present in carriers. Nonsense and frameshift mutations in the NF2 tumor suppressor gene are associated with phenotypes. The clinical abnormalities can develop at a young age.

Optimal timing of retina examinations for premature infants

Developments in modern neonatal intensive care have resulted in increased survival of very premature infants. Along with this increase in survival, there has been a concomitant increase in the frequency of retinopathy of prematurity (ROP). We investigated the relationship between the severity and the time course of ROP as well as the optimal time for retinal examinations of premature infants of various birth weights and gestational ages. A total of 80 premature infants were enrolled for analysis. The mean postnatal age of infants at the time of diagnosis was 7.3 +/- 3.4 weeks for stage 1 retinopathy, 9.2 +/- 5.8 for stage 2 retinopathy, 9.5 +/- 3.8 for stage 3 retinopathy, 10.7 +/- 3.7 for threshold disease, and 11.7 +/- 3.2 for stage 4 retinopathy. The mean postconceptional age of infants at the time of diagnosis was 35 +/- 3 for stage 1 retinopathy, 36.4 +/- 3 for stage 2 retinopathy, 37.6 +/- 3.5 for stage 3 retinopathy, 38.4 +/- 3.5 for threshold disease, and 40 +/- 3.7 for stage 4 retinopathy. The age at the time of the initial detection of ROP was from the ninth to 10th week among infants weighing less than 1,000 g at birth and from the fifth to seventh week among those weighing 1,000 g or more at birth. However, the postconceptional age at the time of initial detection of ROP for the whole group was 36 weeks and was not influenced by birth weight or gestational age. Therefore, we suggest that postconceptional age, rather than postnatal age, should be used to decide the timing of retinal examinations for premature infants.

A comparison of guanosine-quartet inhibitory effects versus cytidine homopolymer inhibitory effects on rat neointimal formation

Phosphorothioate oligodeoxynucleotides (PS oligos) manifest antisense and G-quartet aptameric inhibitory effects on vascular smooth muscle cell (SMC) proliferation. PS oligo cytidine homopolymers also have nonsequence-specific, non-G-quartet inhibitory effects on in vitro and in vivo SMC proliferation. In this study, we compared the effects of S-dC18 and S-dC28, 18-mer and 28-mer cytidine homopolymers, respectively, which lack guanosines, with those of ZK10, a G-tetrad forming compound, on in vitro SMC proliferation and in vivo neointimal formation. ZK10 significantly inhibited in vitro human aortic SMC proliferation. At the same molar concentration, ZK10 had significantly greater inhibitory potency on SMC proliferation than either S-dC18, S-dC28, or 7DG-ZK10, which is a modified ZK10 with ten 7-deaza guanosine substitutions. ZK10 was significantly more potent than S-dC18 and S-dC28 in inhibiting PDGF-induced in vitro SMC migration. S-dC18, S-dC28, and ZK10 treatment significantly reduced the intima/media area ratio after rat carotid artery balloon injury compared with the values of the control groups. ZK10 was a more potent inhibitor of neointimal formation than the same chain length S-dC18. ZK10 formed higher-order structures, as shown on gel electrophoresis, in contrast to S-dC28 and 7DG-ZK10. Therefore, the 18-mer ZK10 has comparable in vivo SMC inhibitory effects to the 28-mer S-dC28, a fact that may have ramifications for the development of optimal PS oligos to inhibit angioplasty restenosis.

Isolated intracranial Rosai-Dorfman disease: case report and literature review

Rosai-Dorfman disease, first described in 1969, is a rare idiopathic histioproliferative disease affecting the lymph nodes. Typical clinical features include bilateral painless lymphadenopathy, fever and polyclonal hypergammaglobulinemia. In approximately 43% of cases, extranodal sites may be involved and occasionally represent the initial or sole manifestation of the disease. Central nervous system manifestations are exceedingly rare, and only 17 cases have been recorded, among which there are merely seven isolated intracranial cases without concurrent nodal or other extranodal involvement. Herein, we report a 38-year-old male presenting with generalized tonic-clonic seizure and radiological findings indicative of meningioma. Complete physical examinations and laboratory surveys demonstrate the absence of involvement at other body sites. Microscopically, the lesion consists of proliferative histiocytes exhibiting emperipolesis coupled with the characteristic cytoplasmic staining against S-100 protein. The differential diagnosis of polymorphic inflammatory meningioma-mimicking masses is discussed, and a review of previously reported intracranial Rosai-Dorfman disease is presented.

A synaptic Ras-GTPase activating protein (p135 SynGAP) inhibited by CaM kinase II

Ca2+ influx through N-methyl-D-aspartate- (NMDA-) type glutamate receptors plays a critical role in synaptic plasticity in the brain. One of the proteins activated by the increase in Ca2+ is CaM kinase II (CaMKII). Here, we report a novel synaptic Ras-GTPase activating protein (p135 SynGAP) that is a major component of the postsynaptic density, a complex of proteins associated with synaptic NMDA receptors. p135 SynGAP is almost exclusively localized at synapses in hippocampal neurons where it binds to and closely colocalizes with the scaffold protein PSD-95 and colocalizes with NMDA receptors. The Ras-GTPase activating activity of p135 SynGAP is inhibited by phosphorylation by CaMKII located in the PSD protein complex. Inhibition of p135 SynGAP by CaMKII will stop inactivation of GTP-bound Ras and thus could result in activation of the mitogen-activated protein (MAP) kinase pathway in hippocampal neurons upon activation of NMDA receptors.

2,3-epoxy-4-hydroxynonanal, a potential lipid peroxidation product for etheno adduct formation, is not a substrate of human epoxide hydrolase

Our previous studies have shown that 2,3-epoxy-4-hydroxynonanal, a reactive epoxy aldehyde capable of forming etheno adducts with DNA bases, is mutagenic and tumorigenic (Carcinogenesis, 14, 2073). The epoxy aldehyde can be generated from trans-4-hydroxy-2-nonenal, a lipid peroxidation product of omega-6 polyunsaturated fatty acids, by autoxidation or by incubation with fatty acid hydroperoxides or hydrogen peroxides (Chem. Res. Toxicol., 9, 306). These are plausible in vivo pathways for the formation of 2,3-epoxy-4-hydroxynonanal. The possibility that 2,3-epoxy-4-hydroxynonanal is a tumorigen of endogenous origin is suggested by recent observations that etheno bases are detected as background DNA lesions in untreated rodents and humans. A metabolic pathway critical for detoxification of 2,3-epoxy-4-hydroxynonanal involves the ring-opening by epoxide hydrolase, which abolishes its ability to form cyclic etheno DNA adducts. In this study, we examined whether 2,3-epoxy-4-hydroxynonanal is a substrate of cDNA expressed human epoxide hydrolase. Human epoxide hydrolase was expressed in TK- 143 cells (thymidine kinase-deficient human embryoblast) infected with recombinant vaccinia virus encoding human epoxide hydrolase cDNA. Controls consisted of the cells infected with vaccinia virus in the absence of human epoxide hydrolase cDNA. No hydrolysis occurred when [2,3-(3)H]2,3-epoxy-4-hydroxynonanal was incubated at 37 degrees C for 30 min at pH 7.4 with cells expressing human epoxide hydrolase, as indicated by the presence of a pair of radioactive peaks in reversed-phase HPLC chromatography, which comigrated with the UV standards of the two diastereomers of the epoxy aldehyde. The identity of these compounds as the intact epoxy aldehyde was further supported by derivatization to the 2,4-dinitrophenylhydrazones followed by reversed phase HPLC analysis. Similar results were observed with the control cells or with the heat deactivated human epoxide hydrolase. The epoxide hydrolase activity in the expressed cells was demonstrated by their ability to convert benzo[a]pyrene-4,5-dihydroepoxide to benzo[a]pyrene-trans-4,5-dihydrodiol under the same conditions. These results clearly indicate that 2,3-epoxy-4-hydroxynonanal is not a substrate of human epoxide hydrolase, and, thus strengthen its possible endogenous role in the formation of promutagenic exocyclic etheno adducts in vivo.

Effect of patient position and hypotensive anesthesia on inferior vena caval pressure

STUDY DESIGN

This is a prospective study to measure the inferior vena caval pressure of 20 patients in different positions and different states of blood pressure.

OBJECTIVES

Because the inferior vena caval pressure could affect the vertebral venous pressure, which in turn may influence blood loss during lumbar spinal surgery, this study was designed to provide the quantitative data necessary to stress the importance of patient positioning and to assess the effect of controlled hypotension on inferior vena caval pressure.

SUMMARY OF BACKGROUND DATA

Positioning patients with a pendulous abdomen and controlled hypotension has been practiced widely during lumbar spinal surgery. It is generally believed that the former will help reduce vertebral venous engorgement and the latter will produce a bloodless surgical wound. However, there have been no complete studies in which quantitative changes of inferior vena caval pressure resulting from different positions was examined. In addition, it would be interesting to know what happens to inferior vena caval pressure during induced hypotension. Could there be an adverse effect on the inferior vena caval pressure during the hypotensive state?

METHODS

An intravenous catheter was introduced into the inferior vena cava in each of 20 patients undergoing spinal surgery. In each patient, the inferior vena caval pressure was measured when the patient was supine, prone on a conventional pad, and prone on a Relton-Hall frame. It was followed by isoflurane-induced hypotension with reduction of mean arterial pressure by 20 mm Hg.

RESULTS

In this series, the inferior vena caval pressure ranged from 8.2 to 23.4 mm Hg (with a mean of 15.3 mm Hg) when patients were positioned prone on a conventional pad. However, when they were subsequently positioned prone on a Relton-Hall frame, the inferior vena caval pressure decreased dramatically to a range of 4.6 to 13.6 mm Hg (with a mean of 8.2 mm Hg). In each patient the measured inferior vena caval pressure when positioned prone on a conventional pad was 1.5 times greater than that measured with the patient positioned on a Relton-Hall frame. There was a statistically significant difference between these two positions (F = 75.996; P < 0.05). The patients' mean arterial pressure ranged from 92 to 105 mm Hg before induced hypotension. During this time, the inferior vena caval pressure ranged from 4.1 to 13.1 mm Hg (mean, 8.2 mm Hg). During the hypotensive state, the patients' inferior vena caval pressure was found to range from 4.2 to 13.6 mm Hg (mean, 8.1 mm Hg). In each patient the hypotensive interior vena caval pressure may be slightly higher or lower than the baseline pressure. However, the variation never exceeded 1.7 mm Hg. Statistically, there was no significant difference between these two periods (t = 0.956; P > 0.05).

CONCLUSIONS

A device allowing the patient's abdominaL viscera to hang freely while the patient is in a prone position significantly reduces their inferior vena caval pressure. The patients also has a constant inferior vena caval pressure during isoflurane-induced hypotension.

Use of DNA transfer in the induction of metastasis in experimental mammary systems

The metastatic spread of cancer is a little understood process, in part because it is difficult to model the entire process using experimental approaches in vitro. The ability to transfer DNA into non-metastatic mammary cells and to observe the induction of metastasis in vivo provides a means for identifying DNA sequences that are associated with the development of metastatic capability. Using these techniques, a metastasis-associated cytoskeletal calcium binding protein, S100A4 (p9Ka), has been identified as an inducer of metastatic capability in benign rat mammary epithelial cells. Metastasis can also be induced in the rat mammary epithelial cells by fragments of DNA from metastatic, but not from benign, human breast tumour cells. These non-coding fragments of DNA act via the induction of osteopontin, an extracellular, integrin binding, calcium binding protein. Since both osteopontin and S100A4 are thought to be associated with malignancy in human breast cancer specimens, gene transfer techniques can identify genes for metastasis-inducing proteins that may play a role in breast cancer, and further suggest that cell migration/motility might be important in the metastatic process.

Inhibitory nonsequence-specific effects of cytidine homopolymers on in vivo neointimal formation

Phosphorothioate oligodeoxynucleotides (PS oligos) manifest both antisense and G-quartet aptameric inhibitory effects on vascular smooth muscle cell (SMC) proliferation. In this study, we examined the effects of three cytidine (S-dC) homopolymers lacking any guanosines of various chain length-S-dC28, S-dC18 and S-dC12-on in vitro SMC proliferation and in vivo neointimal formation. S-dC18 significantly inhibited human vascular SMC proliferation, although it had only half the potency as the same dose of S-dC28. Furthermore, S-dC12 at the same concentrations as S-dC18 did not significantly inhibit vascular SMC proliferation. S-dC28 and S-dC18 inhibited PDGF-induced in vitro SMC migration, whereas D-dC12 had no significant effect on PDGF-induced in vitro SMC migration. We determined the effects of S-dC28, S-dC18, and S-dC12 on neointimal SMC formation in the rat carotid balloon injury model. Rat carotid artery neointimal formation after balloon injury was significantly attenuated by S-dC28 treatment compared with the control group and by S-dC18 treatment compared with the control group. S-dC28 and S-dC18 treatment significantly reduced the intima/media area ratio compared with the values of the control groups. However, S-dC12 did not significantly inhibit neointimal formation. We investigated the time course of the inhibitory effects of S-dC28 on rat carotid artery neointimal formation. S-dC28 significantly inhibited rat carotid artery intimal area and intima/media area ratio at 4 weeks and 8 weeks. Fluoresceinated S-dC28 (FITC-S-dC28) was found to be present throughout the rat carotid arterial wall within 6 hours after balloon injury. Taken together, the potent non-G-quartet, nonsequence-specific inhibitory effects of S-dC compounds on in vitro SMC proliferation and in vivo neointimal formation in the rat carotid balloon injury model are chain length dependent and long lasting.

Cloning and characterization of a rhamnogalacturonan hydrolase gene from Botrytis cinerea

Rhamnogalacturonan hydrolase (Rgase A) cleaves alpha 1--2 linkages between rhamnosyl and galacturonosyl residues in pectin. A 1.9 kb RGase A cDNA clone (BCRHGA) was isolated from a B. cinerea cDNA library using a PCR-amplified Aspergillus aculeatus RGase A probe. It's 1.7 kb open reading frame had 62% identity at the amino acid level with A. aculeatus RGase A. Northern blots of B. cinerea total RNA probed with BCRHGA revealed a 2 kb band, suggesting the cDNA clone is full or nearly-full length. To determine mRNA expression of the gene, B. cinerea was grown in media containing 0.5% apple pectin, 0.5% rhamnogalacturonan-I and 1% glucose carbon sources. Northern analysis revealed the BCRHGA gene was expressed on all carbon sources, but with different patterns of expression. B. cinerea RGase A appeared to be coded for by a single or low copy number gene based on Southern analysis.

Drosophila Mad binds to DNA and directly mediates activation of vestigial by Decapentaplegic

The TGF-beta (transforming growth factor-beta)-related signalling proteins, including Decapentaplegic (Dpp) in Drosophila-and bone morphogenic proteins and activin in vertebrates, affect the growth and patterning of a great variety of structures. However, the mechanisms by which these ligands regulate gene expression are not understood. Activation of complexes of type I with type II receptors results in the phosphorylation and nuclear localization of members of the SMAD protein family, which are thought to act as co-activators of transcription, perhaps in conjunction with sequence-specific cofactors. Here we show that the amino-terminal domain of the Drosophila Mothers against dpp protein (Mad), a mediator of Dpp signalling, possesses a sequence-specific DNA-binding activity that becomes apparent when carboxy-terminal residues are removed. Mad binds to and is required for the activation of an enhancer within the vestigial wing-patterning gene in cells across the entire developing wing blade. Mad also binds to Dpp-response elements in other genes. These results suggest that Dpp signalling regulates gene expression by activating Mad binding to target gene enhancers.

Human acetyltransferase polymorphisms

Conjugation of primary amino and hydroxylamino groups with acetate, catalyzed by acetyl CoA-dependent arylamine acetyltransferase (NAT) enzymes, may play an important role in the intricate series of metabolic pathways that produce or prevent toxicity following exposure to homo- and heterocyclic arylamine and hydrazine xenobiotics. Two independently regulated and kinetically distinct human acetyltransferases are now known to exist, namely NAT1 and NAT2. Interindividual variation in NAT2 function is associated with the classical isoniazid acetylation polymorphism which was discovered over forty years ago. At last count, fifteen variant alleles at the NAT2 gene locus have been linked to the isoniazid 'acetylator phenotype', and each of these can be identified in population studies using specific PCR-based genotyping tests. On the other hand, NAT1 shows kinetic selectivity for compounds whose disposition is unrelated to the classical isoniazid acetylation polymorphism. NAT1 expression is also phenotypically variable in human populations, at least in part due to allelic differences at the NAT1 gene locus. Nine NAT1 variant alleles have been described to date, of which NAT1* 14 and NAT1* 15 clearly produce defective NAT1 proteins and lead to functional impairment in the metabolism of NAT1-selective substrates both in vivo and in vitro. On the other hand, it has been reported that the NAT1* 10 variant associates with elevated NAT1 activity and increased risk for cancers of the bladder and colon. Because of the important toxicologic consequences of allelic variation in NAT1 and NAT2 function for the metabolic activation of arylamine and heterocyclic amine procarcinogens, further studies are needed to improve our understanding of the extent of NAT allelic variation, to determine the functional capacity of each variant gene product, and to develop accurate methods of detecting them in population and epidemiological studies.

Effects of S-dC28 on vascular smooth muscle cell adhesion and plasminogen activator production

We sought to examine phosphorothioate oligodeoxynucleotide (PS oligo) non-G-quartet, nonsequence specific effects on smooth muscle cell (SMC) adhesion by using S-dC28, a 28-mer cytidine homopolymer that lacks contiguous guanosine residues. Human aortic SMC were incubated with vehicle or various doses of S-dC28, and the number of SMC adhered to noncoated plates was determined using a Coulter Counter. S-dC28 significantly inhibited SMC adhesion. SMC adhesion dramatically improved with S-dC28 in fibronectin-coated plates. When laminin-coated plates were used, the inhibition of SMC adhesion by S-dC28 was completely reversed. Replacement of serum-free medium with 5% fetal bovine serum medium for SMC cultured on non-coated plates also greatly attenuated inhibition of adhesion by S-dC28. Human SMC TPA, UPA, and PAI-1 antigen levels were determined by ELISAs. PDGF significantly induced SMC TPA antigen production measured by an ELISA. Coincubation of PDGF with S-dC28 significantly attenuated SMC TPA antigen levels. SMC UPA antigen levels after coincubation with PDGF and S-dC28 were significantly greater than the values observed in SMC incubated in medium containing PDGF alone. SMC PAI-1 antigen levels were not altered by the addition of S-dC28. We conclude that S-dC28 inhibits human SMC adhesion and that this inhibition can be diminished by fibronectin or laminin coating of culture plates or by the presence of serum in the culture medium. Furthermore, S-dC28 attenuates SMC TPA production, thereby inhibiting SMC migration, whereas S-dC28 augments SMC UPA production, thus diminishing SMC cellular adhesion.

Systematic mutational analysis of the cation-independent mannose 6-phosphate/insulin-like growth factor II receptor cytoplasmic domain. An acidic cluster containing a key aspartate is important for function in lysosomal enzyme sorting

We have used systematic mutational analysis to identify signals in the 166-residue murine cation-independent mannose 6-phosphate/insulin-like growth factor II receptor cytoplasmic domain required for efficient sorting of lysosomal enzymes. Alanine cluster mutagenesis on all conserved residues apart from the endocytosis signal demonstrates that the major sorting determinant is a conserved casein kinase II site followed by a dileucine motif (157DDSDEDLL164). Small deletions or additions outside this region have severe to mild effects, indicating that context is important. Single residue mutagenesis indicates that cycles of serine phosphorylation/dephosphorylation are not obligatory for sorting. In addition, the two leucine residues and four of the five negatively charged residues can readily tolerate conservative substitutions. In contrast, aspartate 160 could not tolerate isoelectric or isosteric substitutions, implicating it as a critical component of the sorting signal.

Morphology of intrahepatic duct in surgical treatment of hepatolithiasis

BACKGROUND/AIMS

Surgery is the usual treatment for hepatolithiasis. However, the method of choice is based on intrahepatic duct morphology.

MATERIAL AND METHODS

Six hundred sixty-two patients with hepatolithiasis were operated on in the period between 1980-1994. Hepatolithiasis was clinically classified into primary (75.8%) and secondary (24.2%) types.

RESULTS

Patients treated between 1990-1994 (35.9%), liver resection was performed in 71 patients (69 of left and 2 of the right liver). However, liver resection was chosen only in 6.7% (11/163) during the 1970s. Candidacy for liver resection increased recently due to the increase in primary type. According to the morphology of intrahepatic ducts, the location of stricture was classified into: Central type (n = 59, 30%), Segmental type (n = 101, 51%), and Subsegmental type (n = 21, 10.6%), and unclassified (n = 17, 8.4%). Liver resection was recommended for patients of segmental or subsegmental type. Choledocho-lithotomy with T-tube drainage was indicated in two third of the patients with hepatolithiasis. However, the incidence of post-operative retained stones was very high, and post-operative choledochoscopic lithotripsy was used to treat these post-operative problems easily. The mortality of this disease was 1% (2/198) in the 1990s compared with that of 4.1% (19/464) in 1980s and 10.1% (15/148) in 1970s.

CONCLUSION

We strongly recommend that liver resection for patients with adequate indications will have good results. In addition, one should pay attention to the abnormal pattern of intrahepatic ducts that are commonly found in patients with hepatolithiasis during liver resection. Liver resection is an ideal surgical method for the eradication of diseased lesions and to prevent malignant changes from bile duct with stones. Concise information concerning the anatomic structure was found to be important in determining post-operative results in the management of hepatolithiasis.

T cell lymphokines modulate bFGF-induced smooth muscle cell fibrinolysis and migration

Smooth muscle cell (SMC) fibrinolysis is necessary for SMC migration. To determine whether the T cell lymphokines interleukin 4 (IL-4) and interferon-gamma (IFN-gamma) modulate SMC fibrinolysis and migration induced by basic fibroblast growth factor (bFGF), we examined the effects of IL-4 and IFN-gamma on human SMC tissue-type plasminogen activator (tPA), urokinase-type plasminogen activator (UPA), and plasminogen activator inhibitor 1 (PAI-1) antigen production, determined by enzyme-linked immunosorbent assays. Although IL-4 had no effects on SMC tPA, UPA, and PAI-1 production, it potentiated bFGF-induced tPA, UPA, and PAI-1 antigens. IL-4 plus bFGF resulted in a net increase in SMC fibrinolytic activity. IFN-gamma did not significantly affect bFGF induction of SMC tPA and PAI-1 antigens. However, IFN-gamma significantly decreased bFGF-mediated induction of SMC UPA antigen. IFN-gamma decreased the IL-4 plus bFGF induction of both tPA and UPA antigens. IL-4 increased and IFN-gamma abrogated bFGF induction of in vitro SMC migration through a modified micro-Boyden chamber. Therefore, IL-4 and IFN-gamma modulate bFGF-mediated induction of in vitro vascular SMC fibrinolysis and migration.

Functional and genetic characterization of the oligomerization and DNA binding properties of the Drosophila doublesex proteins

The doublesex (dsx) gene of Drosophila melanogaster encodes both male-specific (DSXM) and female-specific (DSXF) polypeptides, which are required for normal differentiation of numerous sexually dimorphic somatic traits. The DSX polypeptides are transcription factors and have been shown previously to bind through a zinc finger-like domain to specific sites in an enhancer regulating sex-specific expression of yolk protein genes. We have determined the consensus target sequence for this DNA binding domain to be a palindromic sequence AGNNACTAAATGTNNTC composed of two half-sites around a central (A/T) base pair. As predicted by the symmetric nature of this site, we have found that the DSX proteins exist as dimers in vivo and have mapped two independent dimerization domains by the yeast two-hybrid method; one in the non-sex-specific amino-terminal region of the protein and one that includes the partially sex-specific carboxy-terminal domains of both the male and female polypeptides. We have further identified a missense mutation that eliminates dsx function in female flies, and shown that the same mutation prevents dimerization of DSXF in the yeast two-hybrid system, indicating a critical role for dimerization in dsx function in vivo.

Hemifacial spasm caused by a venous angioma. Case report

The authors describe the case of a 53-year-old woman who suffered from a hemifacial spasm caused by a venous angioma in the posterior fossa. At operation the parenchymal segment of the angioma was preserved and vascular decompression was performed by placing pieces of shredded Teflon between the vessel and nerve. After decompression the patient was completely free from spasm.

Identification of a potential physiological substrate for oncogenic Ras-activated protein kinases in activated Xenopus egg extracts: correlation with oncogenic Ras-induced cell cycle arrest

Activated Xenopus egg extracts are capable of undergoing cell-free cell cycling. Using these activated extracts, we previously showed that purified, bacterially expressed oncogenic human RasH protein arrests cell cycle progression. Because oncogenic Ras activates many serine/threonine protein kinases in Xenopus oocytes and egg extracts, it is possible that induction of cell cycle arrest involves the action of oncogenic Ras-activated kinases. Thus, the identification of the physiological substrates for oncogenic Ras-activated kinases is important for elucidating the molecular mechanism underlying oncogenic Ras-induced cell cycle arrest. We used 32P-orthophosphate as a label to identify the potential substrates. Our results demonstrated that the 32P-labeling of both a 32 and a 33 kDa protein were greatly enhanced by oncogenic Ras during the incubation of activated Xenopus egg extracts. The enhanced labeling correlated with the induced cell cycle arrest and was contributed by serine phosphorylation. Moreover, the 33 kDa protein was detected only in the presence of oncogenic Ras and was a serine-hyperphosphorylated form of the 32 kDa protein. Furthermore, new protein synthesis was not required for the enhanced labeling, consistent with the concept that the enhanced serine phosphorylation of the 32 kDa protein is by oncogenic Ras-activated protein kinases. In addition to serine phosphorylation, our results also suggested that an as yet unidentified modification of the 32 kDa protein might also be induced by oncogenic Ras. Our results suggest that the 32 kDa protein is a potential physiological substrate for oncogenic Ras-activated protein kinases.

Postcoital hemoperitoneum without identifiable bleeding source: a case report

Spontaneous intra-abdominal bleeding has been called abdominal apoplexy. It has been so named because its nature and spontaneity closely resemble those of its more common cerebral counterpart. The bleeding source commonly came from a ruptured branch of celiac axis or superior mesenteric artery. Rarely, hemoperitoneum occurs spontaneously post coitus without evident vaginal injury. There were only twelve cases reported in the medical literature to date. Nearly, all of them showed injury of pelvic organs including round or broad ligaments, ovarian cysts or adhesion bands. A case of massive hemoperitoneum after coitus, with no definite bleeding source, is reported.

Lipid peroxidation as a potential endogenous source for the formation of exocyclic DNA adducts

A number of promutagenic exocyclic DNA adducts have recently been detected in both humans and rodents without carcinogen treatment. These observations raised questions about their origins and potential significance in carcinogenesis. In this commentary, we present our views pertaining to the in vivo sources of these cyclic adducts, specifically the cyclic propano and etheno adducts. The basis for our discussion comes mainly from the information generated through a span of more than a decade from several laboratories, including ours. This commentary summarizes the data from the chemical and biochemical studies that provide support for the hypothesis that lipid peroxidation is involved in the endogenous formation of these exocyclic adducts.

Traumatic interdural arachnoid cyst in the upper cervical spine. Case report

The case of an interdural arachnoid cyst of traumatic origin at the C3-5 level in an 18-year-old man was admitted to our hospital with a 1-year history of progressive weakness in left limbs and numbness below the clavicles is reported. He had had a C-2 fracture at the age of 9 years without definite neurological deficits. Magnetic resonance imaging revealed a cystic lesion in the C3-5 level. Laminectomy was performed, and an interdural cyst was found. Histological examination revealed fibrous thickening of the arachnoid membrane. A cyst located in the interdural space of upper cervical spine is extremely rare.