The effects of exopolymers on cell morphology and culturability of Leuconostoc mesenteroides during starvation

Biofilm formation by bacterial cells can be used to modify the subsurface permeability for the purpose of microbial enhanced oil recovery, bio-barrier formation, and in situ bioremediation. Once injected into the subsurface, the bacteria undergo starvation due to a decrease in nutrient supply and diffusion limitations in biofilms. To help understand the starvation response of bacteria in biofilms, the relationship between exopolymer formation and cell culturability was examined in a batch culture. The average cell diameter was observed to decrease from 0.8 micron to 0.35 micron 3 days after starvation began. Cell chain fragmentation was also observed during starvation. Cells that underwent starvation in the presence of insoluble exopolymers showed a slower rate of decrease in cell diameter and in cell chain length than cells without insoluble exopolymers. The rate of decrease in the average cell diameter and cell chain length were determined using a first order decay model. Cells starved in the presence of exopolymers showed greater culturability than cells starved without exopolymers. After 200 days starvation, 2.5 x 10(-3)% cells were culturable, but no increase in cell number was observed. During starvation, the exopolymer concentration remained constant, an indication that the exopolymer was not consumed by the starving bacteria as an alternative carbon or energy source.

Enhanced hepatocyte uptake and liver targeting of methotrexate using galactosylated albumin as a carrier

Liver targeting of drugs has wide therapeutic implications due to numerous liver-related diseases. Using conjugates of methotrexate (MTX) to variously galactosylated bovine serum albumin (BSA), we studied whether we could enhance the liver targeting of MTX, a model drug, via galactose receptors selectively abundant on the hepatocytes. Here, we report that the galactosylation of the carrier protein BSA significantly enhanced the hepatocyte uptake and liver targetability of MTX. In vitro, the amount of MTX taken up by rat hepatocytes was positively correlated with the galactose content in BSA. MTX conjugates were relatively stable in plasma, but released MTX with time in liver homogenates. These results imply that the conjugates would exert low toxicity in the blood, but have therapeutic activity in the liver by liberating MTX. In vivo, MTX-galactosylated BSA conjugates (MTX-L(24)BSA) showed significantly different pharmacokinetics from free MTX or MTX-BSA conjugates. The plasma level of free MTX rapidly declined in a biexponential fashion with an apparent terminal half-life of 0.35 h. MTX-BSA conjugates showed the slowest decline with an apparent terminal half-life of 6 h, whereas MTX-L(24)BSA showed a biphasic pattern; a rapid distributive phase with a half-life of 0.567 h and a slow terminal phase. MTX-L(24)BSA showed the highest liver targetability, when evaluated in terms of two indices based on the area under the total amount of radioactivity-time curve (AUQ); Te*(liver), % AUQ(liver) to total AUQ, and te*, the ratio of AUQ(liver) to AUQ(kidney). Compared with free MTX and MTX-BSA, MTX-L(24)BSA showed about twofold higher Te*(liver) of 87.5%. The te* of MTX-L(24)BSA was 25- and fourfold higher than those of free MTX and MTX-BSA, respectively. Moreover, MTX-L(24)BSA showed a gradual increase in the therapeutically active intact form of MTX in the liver while showing the lowest level of intact MTX in the kidney. These results suggest that galactosylated BSA has a great potential as an hepatocyte-directed and more effective liver targeting carrier of drugs for liver diseases.

Feeding behavior in dopamine-deficient mice

Mice that cannot make dopamine (DA), a condition caused by the selective inactivation of tyrosine hydroxylase in dopaminergic neurons, are born normal but gradually become hypoactive and hypophagic, and die at 3 weeks of age. We characterized the feeding and locomotor responses of these DA-deficient (DA-/-) mice to 3, 4-dihyroxy-L-phenylalanine (L-DOPA) to investigate the relationship between brain DA levels and these complex behaviors. Daily administration of L-DOPA to DA-/- mice stimulated locomotor activity that lasted 6 to 9 hr; during that time the mice consumed most of their daily food and water. The minimal dose of L-DOPA that was sufficient to elicit normal feeding behavior in the DA-/- mice also restored their striatal DA to 9.1% of that in the wild-type (WT) mice at 3 hr; then DA content declined to <1% of WT levels by 24 hr. This dose of L-DOPA induced locomotor activity that exceeded that of treated WT mice by 5- to 7-fold, suggesting that DA-/- mice are supersensitive to DA. Unexpectedly, DA-/- mice manifested a second wave of activity 24 to 48 hr after L-DOPA treatment that was equivalent in magnitude to that of WT mice and independent of DA receptor activation. The DA-/- mice approached, sniffed, and chewed food during this second period of activity, but they ate <10% of that required for sustenance. Therefore, DA-/- mice can execute behaviors necessary to seek and ingest food, but they do not eat enough to survive.

Phase II trial of a novel platinum analog, SKI 2053R, in patients with previously untreated extensive-stage small-cell lung cancer

A phase II trial of a novel platinum analog, SKI 2053R, was performed in patients with previously untreated extensive-stage disease (ED) small-cell lung cancer (SCLC). SKI 2053R was administered at the dose of 400 mg/m2 every 3 to 4 weeks as a 1-h infusion. After the first cycle, the dose was escalated to 440 mg/m2 based on toxicity. Thirty-eight patients (31 male) were enrolled between June 1995 and August 1997. The median age was 61 years (range, 36-70 years). Six of 37 evaluable patients achieved a partial response (16.2%; 95% confidence interval [CI], 4.4-28.0%). The durations of response were 1.1, 1.5, 1.7, 1.9, 3.4, and 4.6 months. The estimated median survival time was 7.4 months (95% CI, 5.1-9.7 months). Grade 3 or 4 toxicities were not observed. Grade 1 to 2 leukopenia, anemia, and thrombocytopenia were seen in 5 of 68 cycles, 16 of 68, and 2 of 68, respectively. Nonhematologic toxicities included grade 1 to 2 nausea or vomiting (30 of 68 cycles), nephrotoxicity (27 of 68), and hepatotoxicity (13 of 68). SKI 2053R showed a modest antitumor activity with limited toxicities in patients with ED SCLC. Further clinical trials are warranted in SCLC with a higher dose of SKI 2053R.

The effect of varying inspiratory to expiratory ratio on gas exchange in partial liquid ventilation

BACKGROUND

In partial liquid ventilation (PLV), the nondependent lung was observed to be inflated first and the dependent lung later. The inflational time difference between the lung regions can lead to maldistribution of tidal gas and inefficient gas bubbling in the slow-inflating region during PLV. In this situation, increasing the inspiratory to expiratory (I:E) ratio of the mechanical ventilator would lessen the heterogeneity of regional ventilation and improve gas exchange possibly to a greater degree than in gas ventilation (GV).

DESIGN AND SETTING

Animal study at the Asan Institute for Life Sciences, Seoul, Korea Subjects: Eighteen rabbits (2.6 +/- 0.5 kg) with acute lung injury by saline solution lavage.

INTERVENTIONS

Three I:E ratios were tried in GV and then in PLV. I:E ratios were changed by adjusting pause (1:2, 1:1, and 2:1; group 1) or by adjusting inspiratory flow rate (1:3, 1:1, and 2:1; group 2).

MEASUREMENTS AND RESULTS

With increasing I:E ratio in all animals, PaO(2)/FIO(2) increased (80 +/- 24, 143 +/- 74, and 147 +/- 88 mm Hg; p = 0.001), and PaCO(2) decreased (74 +/- 15, 66 +/- 16, and 66 +/- 15 mm Hg; p = 0.006). The increases of PaO(2)/FIO(2) from 1:2/1:3 to 1:1 (p = 0.006) and from 1:1 to 2:1 (p = 0.036) were both greater in group 1 than in group 2. PaCO(2) decreased with increasing I:E ratio in group 1, but not in group 2. The change of PaO(2)/FIO(2) by varying the I:E ratio was 49 +/- 65% in PLV and 14 +/- 14% in GV (p = 0.003).

CONCLUSIONS

Extending the I:E ratio, especially by adding pause, improved gas exchange in PLV. Oxygenation in PLV was affected by the I:E ratio to a greater degree than in GV.

Percutaneous transmyocardial revascularization induces angiogenesis: a histologic and 3-dimensional micro computed tomography study

The purpose of this study was to visualize the spatial patterns and connection of channels created after percutaneous transmyocardial revascularization (PTMR) in normal porcine hearts, and to estimate the relative contributions of transmyocardial and coronary perfusion. Six pigs underwent PTMR creating channels using radiofrequency ablative energy. Three-dimensional computed tomography imaging of channels 1 hr after PTMR showed the direct connection of PTMR channels to the myocardial capillary network and to epicardial coronary vessels. In the heart, examined 28 day after PTMR, there was a fine, extensive, network of microvessels originating from the site of the original PTMR channel, also connecting the left ventricular cavity to myocardial capillaries. Histopathologic examination of the 1-hr specimens showed numerous regions of myocardial hemorrhage and associated inflammatory cell infiltration. In the 28-day specimens, newly developed new vascular network suggested neovascularization within the core of these channel remnants. The immunoreactivity for basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) were intense within myocardium and neovascular structure surrounding PTMR channel remnants. The vascular connections occur by direct communication with existing myocardial vasculature acutely, and angiogenesis in these channel remnant chronically.

Anterior thalamoperforating artery aneurysm associated with internal carotid artery occlusion: case report

OBJECTIVE AND IMPORTANCE

We describe a rare case of a ruptured distal anterior thalamoperforating artery aneurysm associated with right internal carotid artery occlusion.

CLINICAL PRESENTATION

A 59-year-old woman experienced sudden occipital headache, vomiting, and subsequent coma as a result of massive intraventricular hemorrhage. An initial angiogram revealed only an occlusion of the right internal carotid artery just distal to the posterior communicating artery. Repeat angiography 1 month later, however, revealed a saccular aneurysm at a distal anterior thalamoperforating artery in addition to the occlusion of the internal carotid artery.

INTERVENTION

We approached this aneurysm through the right temporal horn after opening the ambient cistern. The aneurysm, which was located in the brain parenchyma just medial to the temporal horn, was successfully resected.

CONCLUSION

This rare aneurysm probably developed as a result of hemodynamic stress on the anterior thalamoperforating artery after occlusion of the internal carotid artery and/or secondary to chronic hypertension.

Two-color femtosecond experiments by use of two independently tunable Ti:sapphire lasers with a sample-and-hold switch

We performed femtosecond two-color experiments (four-wave mixing and pump probe) using two independently tunable, partially synchronized femtosecond lasers. Despite the fact that the jitter is of the order of 5-10 ps, the time resolution is limited only by the pulse width when a homemade sample-and-hold switch is used.

Expression of mRNAs encoding full-length and truncated TrkB receptors in rat dorsal root ganglia and spinal cord following peripheral inflammation

Peripheral inflammation induces an increased brain-derived neurotrophic factor (BDNF) synthesis in the dorsal root ganglion (DRG) and an elevated anterograde transport of BDNF to axon terminals in the spinal dorsal horn. To characterize whether expression of trkB is modulated in response to BDNF elevation in these areas, we evaluated changes in expression of full-length and truncated trkB (trkB.FL and trkB.T) mRNAs after injection of complete Freund's adjuvant into the hind paw of the rat. Reverse transcription-polymerase chain reaction analysis revealed that BDNF and trkB.T mRNAs levels in the DRG increased, while no change of expression of trkB.FL mRNA was observed. There was no detectable change in both trkB.FL and trkB.T mRNAs levels in the spinal cord. Considering that trkB.T mRNA is expressed mainly in the perineuronal satellite cells, these results suggest a possible paracrine role of BDNF within the DRG in addition to an important role related with nociception following peripheral inflammation.

Response to chloroquine of Plasmodium vivax among South Korean soldiers

The response to standard chloroquine treatment was evaluated, by microscopical examination of blood-smears, among 81 soldiers diagnosed with Plasmodium vivax malaria in South Korea in 1996. The smears were prepared pre-treatment and 3, 14 and 28 days after starting chemotherapy. Parasitaemias were determined after staining the smears with Giemsa's stain. Blood samples from the patients who were not smear-negative by day 3 were carefully checked for parasites, by staining smears with Acridine Orange and by a PCR-based assay. Only two of the patients appeared to be parasitaemic on day 14 and were therefore considered treatment failures. Although both were apparently cured after additional therapy with the same regimen, one had a recurrence 8 months later. Most cases of recent, resurgent malaria in South Korea therefore appear to sensitive to chloroquine.

Quantitative assessment of cerebrospinal fluid hydrodynamics using a phase-contrast cine MR image in hydrocephalus

This investigation was undertaken to characterize CSF flow at the level of the aqueduct of Sylvius with a phase-contrast cine MR pulse sequence in 28 healthy volunteers. Sixteen patients with obstructive hydrocephalus and 11 patients with normal pressure hydrocephalus (NPH) were investigated with the same sequence before and after CSF diversion. The peak CSF flow velocity and stroke volume in the aqueduct increased significantly in the NPH group and decreased significantly in the obstructive hydrocephalus group. After lumboperitoneal shunting in the NPH group, the retrograde flow of CSF was anterogradely converted and the peak flow velocities decreased somewhat. The clinical diagnosis of NPH was well correlated with the results of cine MRI. After endoscopic III ventriculostomy in the obstructive hydrocephalus group we noted increased CSF flow velocity with markedly increased stroke volume at the prepontine cistern. Phase-contrast cine MR is useful in evaluating CSF dynamics in patients with hyperdynamic aqueductal CSF or aqueductal obstruction.

Expression of the HMGI(Y) gene in human colorectal cancer

Expression of HMGI(Y), a nucleoprotein that binds to A/T rich sequences in the minor groove of the DNA helix, is observable in neoplastically transformed cells but not in normal cells. We have analyzed HMGI(Y) expression in colorectal cancer and evaluated its clinicopathologic significance. HMGI(Y) mRNA was measured by CRT-PCR (competitive reverse transcription-polymerase chain reaction). Immunohistochemical staining for HMGI(Y), p53 and Ki-67 was performed in the same colon cancer tissues, and the results in colorectal tissues were similar to those of RT-PCR. HMGI(Y) expression evidenced by RT-PCR was observed in 63 of 64 (98.4%) colorectal cancer samples, and 2 of 5 (40%) adenomatous polyps, whereas 21 normal colon samples were negative (p<0.001). High HMGI(Y) expression using CRT-PCR was found in colon cancers with a high Ki-67 labeling index (p<0.001). There was no significant correlation between the levels of HMGI(Y) expression and stage, tumor size, lymph node metastasis, histologic grade and immunohistochemical status of p53. Our results indicate that the HMGI(Y) expression may occur at an early stage of carcinogenesis and correlate with cell proliferation. Int. J. Cancer (Pred. Oncol.), 84:376-380, 1999.

Geometrical and topological relationships between multiple functional maps in cat primary visual cortex

The mammalian striate cortex is organized such that the receptive field properties of neighboring neurons change gradually across the cortical surface, forming so-called cortical maps. The presence of such maps has been demonstrated in different species of mammals for several parameters characterizing the visual space: retinotopy, ocular dominance, orientation, direction of motion and spatial frequency. In this study we used the optical imaging of intrinsic signals to simultaneously record the multiple functional maps in the same animal in order to obtain a comprehensive set of rules that govern mutual dependencies among the functional maps. Our results indicate that while orientation, direction and ocular dominance are represented on the cortex in a mutually dependent manner, the representation of spatial frequency is independent of the other types of cortical representations. The presence and/or absence of mutual dependence among the multiple functional maps are suggested to provide an important clue for the understanding of the development of visual cortical information representation in neonatal animals.

A novel disintegrin salmosin inhibits tumor angiogenesis

Salmosin is a snake venom-derived novel disintegrin that antagonizes platelet aggregation. In this study, we investigated its functional specificity in tumor angiogenesis. Salmosin significantly inhibited bovine capillary endothelial cell proliferation induced by basic fibroblast growth factor but had no effect on normal growth of the cell. The basic fibroblast growth factor-induced in vivo angiogenesis in the chorioallantoic membrane was disrupted by salmosin treatment without affecting normal embryonic angiogenesis. Adhesion of the bovine capillary endothelial cells to vitronectin was also inhibited by the binding of salmosin to the alpha(v)beta3 integrin. Both the metastatic-tumor growth and the solid-tumor growth that developed in mice were effectively suppressed by salmosin treatment. Several lines of experimental evidence strongly suggest that the tumor-specific antiangiogenic activity of salmosin disrupts tumor growth by blocking the alpha(v)beta3 integrin that is expressed on the vascular endothelial cell surface.

Elevated serum interleukin-15 levels in systemic lupus erythematosus

Interleukin-15 (IL-15) has multiple biological properties, including the induction of other cytokine production and the inhibition of T cell apoptosis. Recently, IL-15 was reported to have a major role in synovial inflammation of rheumatoid arthritis, and that it provokes and amplifies the inflammatory process through the activation of TNF-alpha production. In systemic lupus erythematosus (SLE), the dysregulation of apoptosis and various cytokine production were observed and have been implicated in the pathogenesis of SLE. Thus, we tried to determine serum IL-15 levels in SLE patients and to assess the relationship among IL-15 levels, TNF-alpha levels and disease activity of SLE. Twenty SLE patients and 10 controls were studied. Paired serum samples were collected from all SLE patients at the time of presentation with active disease and at 4 weeks after institution of treatment. IL-15 levels were determined by ELISA and compared with the disease activity indices in SLE. The disease activity of SLE was measured using the SLE Disease Activity Index (SLEDAI) and laboratory parameters such as circulating immune complex (CIC), C3, C4, anti-DNA antibody, IgG, IgM, and IgA. The IL-15 levels in SLE patients were significantly higher than those of controls (5.38 +/- 4.89 vs. 1.04 +/- 1.26 pg/ml). However, elevated IL-15 levels did not correlate with the SLEDAI, nor did they correlate with other laboratory activity indices. The changes in serum IL-15 levels did not correlate with the changes in serum TNF-alpha in the disease course of SLE patients, whereas TNF-alpha reflected the changes in disease activity of SLE. Serum levels of IL-15 are elevated in SLE patients, but IL-15 did not correlate with the disease activity of SLE. TNF-alpha production in SLE patients was unlikely to be related with IL-15.

Congenital intraorbital optic nerve cyst. Case report

Congenital cystic lesions of the optic nerve are exceedingly rare; only one case is reported in the world literature. The authors describe a case of congenital simple glial cyst in the intraorbital portion of the optic nerve with a brief review of the literature and comment on its histogenesis. A 45-day-old male infant was admitted to the hospital because of progressive proptosis and hypotropia in the left eye, which had been present since birth. Magnetic resonance imaging of the left orbit revealed an ovoid, well-demarcated, homogeneous cystic mass in the intraconal retrobulbar area. The mass compressed the left eyeball with downward and lateral displacement. The wall of the cystic mass was very thin, and a needle puncture of the cyst released clear, colorless, watery fluid. The cystic wall was lined by loose astroglial nerve fibers with some scattered glial cells.

Expression of brain-derived neurotrophic factor in catecholaminergic neurons of the rat lower brainstem after colchicine treatment or hemorrhage

Widespread brain-derived neurotrophic factor messenger RNA expression has been detected in the region of catecholamine groups of the rat lower brainstem, while few brain-derived neurotrophic factor-immunoreactive cells were found in this area. In the present study, a double-color immunofluorescence technique for brain-derived neurotrophic factor and tyrosine hydroxylase after colchicine treatment was employed to evaluate the possible presence of brain-derived neurotrophic factor immunoreactivity in the catecholaminergic cells of the rat lower brainstem. We detected many new brain-derived neurotrophic factor-immunoreactive cells in the A1, A2, A4, A6-A10 and C1-C3 cell groups and in the other lower brainstem nuclei where, without colchicine treatment, brain-derived neurotrophic factor messenger RNA was expressed, but not brain-derived neurotrophic factor immunoreactivity. In addition, the catecholaminergic neurons were found to express brain-derived neurotrophic factor immunoreactivity with the co-existence being greatest, in percentage terms, in medullary catecholaminergic cell groups. Hypotensive hemorrhage, which activates medullary catecholaminergic neurons, induced the expression of brain-derived neurotrophic factor immunoreactivity in catecholaminergic neurons (A1/C1 and C2). The results demonstrate that brain-derived neurotrophic factor is regulated by neuronal activity in medullary catecholaminergic cell groups involved in central cardiovascular regulation.

Semisynthesis of abrusoside A methyl ester

Abrusoside A methyl ester was prepared from abrusogenin through methylation (CH2N2) and a subsequent coupling reaction with 1-chloro-2,3,4,6-tetra-O-acethylglucopyranose in the presence of AgOTf and TMU in CH2Cl2, followed by deacetylation using K2CO3 in MeOH-H2O.

An immunohistochemical analysis of heat shock protein 70, p53, and estrogen receptor status in carcinoma of the uterine cervix

OBJECTIVES

It has been shown that heat shock proteins (HSPs) protect cells from death caused by various noxious stimuli. Overexpression of HSP70 seems to be related to hormonal regulation of cell proliferation and/or down-regulation of sex steroid receptors. Wild-type p53 has been reported to repress HSP70 gene expression. It has been shown that mutant p53-HSP70 complex is highly expressed in cancer. However, the relationship between HSPs and steroid receptors or tumor suppressor gene products has not been well understood in uterine cervical carcinoma. This study was undertaken to examine the expression of HSP70, estrogen receptor (ER), and p53 in carcinoma of the uterine cervix. In addition, we analyzed HPV infection status and compared it to such immunohistochemical parameters. We also analyzed the relationship between these biological products and their clinicopathologic characteristics.

METHODS

Paraffin-embedded tissue sections were obtained from 84 patients with carcinoma of the uterine cervix. Expression of HSP70, p53, and ER was evaluated by immunohistochemical staining using anti-HSP70 monoclonal antibody (SPA810), anti-p53 (BP53.12), and ER1D5 antibody, respectively. PCR HPV detection was done by dot hybridization method.

RESULTS

Positive staining of HSP70 was detected in 73% of the cases. HSP70 positivity was significantly higher in stage I cervical cancer than in stages II-IV (P = 0.02). This was associated with neither tumor size, lymph node status, parametrial involvement status, nor tumor markers (TA-4). Furthermore, there was no significant correlation between HSP70 positivity and the expression of p53 or ER or HPV infection status.

CONCLUSION

These data suggested that HSP70 positivity was frequent in uterine cervical cancer, especially in the early stages. However, this was not significantly correlated with clinicopathologic characteristics nor with the expression of p53 or ER nor with HPV infection in carcinoma of the uterine cervix.

Effectiveness of rotor off fraction in allogeneic murine bone marrow transplantation with complete disparity of major histocompatibility

Counterflow centrifugal elutriation (CCE) has been a highly efficient physical method for separating T cells from bone marrow (BM) without impairing cell function and yield. To investigate the usefulness of CCE, the hematopoietic potential as well as the level of T cell contamination in rotor-off (R/O) fraction of BM was studied using a murine bone marrow transplantation (BMT) model [C3H/He (H-2k)-->BALB/C (H-2d)]. The total recovery of cells after CCE procedure was 71.4%. Morphologically, R/O fraction contained abundant mononuclear cells and a few lymphocytes. The numbers of colony forming unit for granulocyte/monocyte (CFU-GM), Sca-1+ cells, and T cells were compared among four fractions of CCE (fractions at flow rate of 17, 25, 28 mL/min, and R/O fraction). The number of CFU-GM per 10(5) nucleated cells in each fraction were significantly higher in R/O fraction (331.3 +/- 34.4) compared to unfractionated marrow (UM) (21.1 +/- 1.3) and fraction of 17 mL/min (FR 17) (23.7 +/- 2.2 ) (chi2 = 0.0044). Neither fraction of 25 mL/min (FR 25) nor fraction of 28 mL/min (FR 28) contained CFU-GM colonies. The concentration of Sca-1+ cells in R/O fraction was significantly higher (1.96-fold) than UM (p < 0.05), and 80.0 +/- 10.1% of Sca-1+ cells in UM were recovered in R/O fraction; 88.1% of Thy-1.2+ T cells were eliminated in R/O fraction (p < 0.05). Mice receiving UM after lethal irradiation (875cGy) suffered from severe graft-versus-host disease (GVHD) and all five died within 7 days after BMT procedure (Group A). Of interest, mice receiving mixture of R/O fraction with lymphocyte-rich fraction (FR 25 plus FR 28) to equalize T cell number as UM, developed severe GVHD and four out of five died (probability of survival; 20%) (Group B). Mice receiving R/O fraction had mild GVHD and four out of five survived for at least 90 days (probability of survival; 80%) (Group C). In group C, probability of survival (p = 0.0006) was higher, and severity of GVHD (p = 0.0043) and progression rate of GVHD (p = 0.02) was lower. In conclusion, the elutriated R/O fraction cells of BM have the advantages of stable engraftment and tolerable GVHD in murine allogeneic BMT with complete major histocompatibility disparity. This could be directly applicable to patients with high risk of GVHD and graft failure in upcoming clinical trials.

Morphological variations of the peripapillary circle of Zinn-Haller by flat section

AIMS

To evaluate the morphometric and morphological variations of the circle of Zinn-Haller (CZH) in the human eye.

METHODS

42 human enucleated eyes were used in this study. After transverse flat thick sections were cut through the optic nerve and adjacent sclera, tissue sections were stained with haematoxylin and eosin or examined immediately by wet preparation under a light microscope. The average vessel diameter of the arterial circle and the average distance between the optic nerve head (ONH) and the arterial circle were determined. Various branching patterns of the CZH were also evaluated.

RESULTS

The vessel diameter of the arterial circle was 123 (SD 75) microm (range 20-230 microm). The distance of the CZH from the ONH margin was 403 (352) microm (0-1050 microm). The CZH gave off branches to the optic nerve and to the peripapillary choroid (PPC) with various branching patterns especially at the entry point of paraoptic short posterior ciliary artery.

CONCLUSIONS

The CZH exists within a variable distance from the ONH and its average diameter is similar to that of the central retinal vessels though it shows marked variation even in the same circle. The CZH also shows variable configurations in branching patterns. These variations may act as contributing factors that are responsible for the individual susceptibility of the anterior optic nerve and the PPC to circulatory disturbances.

Endoscopic approach to arachnoid cyst

A prospective study of 36 consecutive patients with congenital arachnoid cysts treated endoscopically is reported. There were 15 female and 21 male patients. The mean age at the time of diagnosis was 12.3 years (10 days to 38 years). Arachnoid cysts were located in the suprasellar region in 16 patients, the sylvian fissure in 11, the quadrigeminal cistern in 4 and the posterior fossa in 5. Endoscopic fenestration was combined with cysto-peritoneal shunting for 6 temporal cysts and with ventriculo-peritoneal shunting in 1 suprasellar cyst. Mean postoperative follow-up was 4.2 years (range 1-8 years). Follow-up imaging studies showed that 28 arachnoid cysts (77.8%) were obliterated after endoscopic procedures. Long-term clinical results were good in all patients, although the cysts of 8 patients were not reduced in size. There was no mortality or morbidity. We conclude that endoscopic procedures may be a promising alternative to microsurgical operations or shunting for the treatment of arachnoid cysts.

Molecular cloning and functional characterization of a snake venom metalloprotease

A cDNA clone, MT-d, encoding metalloprotease precursor was isolated from snake (Agkistrodon halys brevicaudus) venom gland cDNA library. MT-d-I protein containing both metalloprotease and disintegrin domains, and MT-d-II protein containing the metalloprotease domain only were expressed in Escherichia coli and refolded successfully into their functional forms. Each of the refolded enzyme species exhibited distinct substrate specificity. Proteolytic activity of the MT-d-1 was able to hydrolyse type I gelatin, type-III and V collagens in contrast with the catalytic function of MT-d-II. MT-d-I protein having metalloprotease activity was also able to inhibit platelet aggregation. Functionally active MT-d-I protein underwent autoproteolytic processing in vitro to produce metalloprotease and disintegrin; this processing was accompanied by significant changes in the substrate specificity of the enzyme activity. Experimental evidence strongly suggests that the disintegrin domain in the metalloprotease precursor modulates the catalytic function of the enzyme in hydrolysing extracellular matrix proteins.

cDNA cloning of the CEPUS, a secreted type of neural glycoprotein belonging to the immunoglobulin-like opioid binding cell adhesion molecule (OBCAM) subfamily

GP55 is a family of glycoproteins distributed predominantly in the nervous system, and its previously characterized members, including the GP55A (EMBL Y08170) and E19S (EMBL Y08171) reveal a typical glycosyl phosphatidyl inositol (GPI)-anchored pattern for membrane proteins. CEPUS identified in this study appeared to represent the third member of GP55. This 3.2 kb long complete cDNA clone from the chicken brain exhibited 3 Ig-like domains. The open reading frame of CEPUS contains 313 amino acids, which can encode a 31.7 kDa core protein (pI 5.75) for the mature form. The signal peptide cleavage site was predicted at Gln25. The structural features of the CEPUS cDNA sequence represented a soluble counterpart to the recently identified cerebellar Purkinje cell specific antigen, CEPU-1. The sequence difference between CEPU-1 and CEPUS was only found in the C-terminus in which the CEPUS lacked the GPI-anchored binding site. It displays significant sequence homology to GP55-related molecules, including OBCAM, GP55A, E19S/LAMP, neurotrimin, and CEPU-1, which are all membrane attached types. The absence of the hydrophobic tail sequence in CEPUS may, therefore, suggest that CEPUS would represent the first identified secreted member in this group of genes. We defined that this molecule forms the opioid-binding cell adhesion molecule (OBCAM) subfamily in the molecular phylogeny. Structurally, these molecules represent acidic proteins (pI 5.47-6.09). Six cysteins, as well as 5 Asn-linked potential glycosylation sites were evolutionary-conserved, suggesting that this OBCAM subfamily resembles immunoglobulin-like and highly glycosylated molecules. The presence of CEPUS would probably suggest to us that the spatial/local expression of the CEPU gene may provide a favorable route for migrating CEPU-positive population of neurons to generate a neuron-specific guidance in developing neurons in vivo.