Microsurgical anatomy for lateral approaches to the foramen magnum with special reference to transcondylar fossa (supracondylar transjugular tubercle) approach

Microsurgical anatomy for lateral approaches to the foramen magnum, especially for transcondylar fossa (supracondylar transjugular tubercle) approach, was studied using cadavers. The transcondylar fossa approach is an approach in which extradural removal of the posterior portion of the jugular tubercle through the condylar fossa is added to the far lateral approach. Some differences between this approach and the transcondylar approach are demonstrated. The atlanto-occipital joint and the jugular tubercle are obstacles for the lateral approaches. The condylar fossa forming the external occipital surface of the jugular tubercle is located supero-posterior to the occipital condyle. The fossa is limited laterally by the sigmoid sulcus and the jugular foramen. The posterior condylar canal communicating anteriorly with the distal end of the sigmoid sulcus, the jugular foramen, or the hypoglossal canal opens at the bottom of the fossa. The condyle is situated inferior to the posterior condylar and hypoglossal canals, and the jugular tubercle is located superior to them. In the transcondylar fossa approach the posterior part of the jugular tubercle is extradurally removed, but the condyle and the atlanto-occipital joint are untouched. On the other band, in the transcondylar approach the medial parts of the condyle and the lateral mass of Cl are removed. The latter approach offers better visualization of the inferior part of the foramen magnum. The essential difference of the two approaches is in the direction of looking and the extent of resection of the atlanto-occipital joint. Both approaches offer excellent view of the ventral dural space in the lower clivus and the foramen magnum, but the level of exposure differs somewhat between them. In the lateral approaches to the foramen magnum, the condylar fossa, the posterior condylar canal, and the posterior condylar emissary vein all play an important role as intraoperative anatomical landmarks.

Clinical course of abducens nerve palsy associated with skull base tumours

BACKGROUND

The clinical course of abducens nerve palsy associated with skull base tumour is rarely reported. In this study, we examined the post-operative course of abducens nerve palsies associated with various skull base tumours.

METHOD

Between January 2003 and December 2006, 240 patients with various skull base tumours underwent surgery at Kyushu University Hospital. Among them, nine patients presented with abducens nerve palsies (ten nerves) following surgery. The conditions included two pituitary adenomas, two trigeminal schwannomas and five meningiomas. We evaluated the function of the abducens nerves in these patients on admission, at discharge, and periodically in the outpatient clinic.

FINDINGS

Four of the abducens nerve palsies already existed prior to surgery, and six of them developed post-operatively. In the four patients with pituitary adenomas and trigeminal schwannomas, all nerves were anatomically preserved and showed complete recovery of function within 6 months after surgery. In contrast, only two of the six palsies in patients with skull base meningiomas showed complete recovery. In three patients with petro-clival meningiomas, the abducens nerves were completely transected during surgery, and one was reconstructed using fibrin glue. This patient remarkably recovered from the abducens nerve palsy within 2 years.

CONCLUSIONS

The abducens nerve palsies in pituitary adenomas and trigeminal schwannomas showed a better clinical course compared to those in skull base meningiomas. The abducens nerve palsies that occur with skull base meningiomas are less likely to recover. Nevertheless, it is important to preserve the nerves and to perform surgical repair if the nerve is transected.

Nephritogenic Glycoprotein X

When triglycosyl glycopeptide ( nephritogenoside ) was contaminated with glucosyl, galactosyl, mannosyl, and heteropolysaccharide glycopeptide, a mixed lesion of proliferative glomerulonephritis ( PGN ) with immunofluorescent mesangial pattern and membranous glomerulonephritis (MG) with immunofluorescent granular pattern resulted. It was concluded that PGN was caused by the presence of nephritogenoside and MG by the presence of the heteropolysaccharide glycopeptide in the crude nephritogenic glycopeptide mixtures derived from various solubilization steps used to treat the kidney extracts. Trichloroacetic acid treatment of crude nephritogenic glycopeptide mixtures precipitated the heteropolysaccharide glycopeptide of the MG-inducing factor, thus permitting the separation of nephritogenoside from the heteropolysaccharide glycopeptide by a rather simple technique. Both the heteropolysaccharide glycopeptide and Heymann's antigen (so-called tubular antigen) have a common antigenic substance, but we cannot conclude, at the present state, that both substances are chemically the same. The degree of contamination of pure nephritogenoside by this substance that is antigenically the same as Heymann's antigen (in pure nephritogenoside ) can be chemically and accurately determined, based on the evidence that pure nephritogenoside is a glycopeptide having only three glucose residues as the sugar moiety, that is, by estimating the amount of contaminated monosaccharide components such as galactose, mannose, and N-acetylglucosamine.

Surgical indications for arteriovenous malformations in patients over the age of 60 years: retrospective analysis of 33 patients

This retrospective study investigated the surgical indications in 33 patients aged > 60 years with brain arteriovenous malformation (AVM) taken from a group of 294 cases between 1981 and 2004. These 33 patients were further classified to two age groups: 60 - 64 years (A group) and > or = 65 years (B group). The overall haemorrhagic rate at initial presentation was 46.6% in the 294 patients. The rate was 48.5% in patients aged > 60 years, and 72.2 and 20% in the A and B groups, respectively. In three of four cases with extremely poor outcome with modified Rankin Scale 5 and 6, the cause of poor outcome was haemorrhage in those aged > 65 years. Because of the high haemorrhagic rate and poor outcome after haemorrhage, surgical treatment is indicated for patients aged > 60 years.

Mesangial cell apoptosis induced by a fibronectin fragment

We previously showed that in passive Heymann nephritis (PHN) rats, a large quantity of fibronectin (FN) fragments containing the central cell-binding (CCB) domain and adjacent domains are generated in the kidney and excreted into urine (Nishizawa et al., Biol Pharm Bull 1998; 21: 429-433). To ascertain whether the FN fragments could affect the progression of PHN, we investigated the effect of a 150 K FN fragment containing the CCB and carboxyl-terminal heparin-binding (Hep 2) domains on cultured rat mesangial cells. When rat mesangial cells cultured on FN-coated plates were exposed to the 150 K FN fragment, some mesangial cells detached from the FN substrate and then underwent apoptosis as judged by nuclear and DNA fragmentations. The 150 K FN fragment competitively inhibited the mesangial cell adhesion to the FN substrate in a dose-dependent manner. Furthermore, gelatinzymography of the conditioned medium of mesangial cells showed that the 150 K FN fragment induced and/or potentiated the extracellular matrix (ECM)-degrading proteinases including matrix metalloproteinases (MMPs) of mesangial cells. These results indicate that the 150 K FN fragment may elicit mesangial cell apoptosis by disrupting the mesangial cell adhesion through two distinct ways: the inhibition of mesangial cell adhesion and the ECM-degradation by the 150 K FN fragment-induced MMPs. Thus, FN fragments containing the CCB and adjacent domains generated in the kidneys of PHN rats may be involved in the evolution of the renal injury.

Surgery on a saccular vertebral artery-posterior inferior cerebellar artery aneurysm via the transcondylar fossa (supracondylar transjugular tubercle) approach or the transcondylar approach: surgical results and indications for using two different lateral skull base approaches

OBJECT

The authors report on the surgical results they achieved in caring for patients with vertebral artery-posterior inferior cerebellar artery (VA-PICA) saccular aneurysms that were treated via either the transcondylar fossa (supracondylar transjugular tubercle) approach or the transcondylar approach. In this report they clarify the characteristics of and differences between these two lateral skull base approaches. They also present the techniques they used in performing the transcondylar fossa approach, especially the maneuver used to remove the jugular tubercle extradurally without injuring the atlantooccipital joint.

METHODS

Eight patients underwent surgery for VA-PICA saccular aneurysms (six ruptured and two unruptured ones) during which one of the two approaches was performed. Clinical data including neurological and radiological findings and reports of the operative procedures were analyzed. The Glasgow Outcome Scale was used to estimate the activities of daily living experienced by the patients. In all cases the aneurysm was successfully clipped and no permanent neurological deficits remained, except for one case of severe vasospasm. In seven of the eight patients, the transcondylar fossa approach provided a sufficient operative field for clipping the aneurysm without difficulty. In the remaining patient, in whom the aneurysm was located at the midline on the clivus at the level of the hypoglossal canal, the aneurysm could not be found by using the transcondylar fossa approach; thus, the route was changed to the transcondylar approach, and clipping was performed below the hypoglossal nerve rootlets.

CONCLUSIONS

Both approaches offer excellent visualization and a wide working field, with ready access to the lesion. This remarkably reduces the risk of development of postoperative deficits. These approaches should be used properly; the transcondylar fossa approach is indicated for aneurysms located above the hypoglossal canal and the transcondylar approach is indicated for those located below it.

Surgical treatment of glossopharyngeal neuralgia as vascular compression syndrome via transcondylar fossa (supracondylar transjugular tubercle) approach

OBJECTIVE

These are the first reported cases in whom the transcondylar fossa approach was applied for the treatment of glossopharyngeal neuralgia (GPN) as a vascular compression syndrome.

CASES PRESENTATION

All three cases presented with severe paroxysmal pharyngeal pain which could not be controlled by medical treatment. The patients all underwent microvascular decompression surgery (MVD) via transcondylar fossa approach. The posterior inferior cerebellar artery or the anterior inferior cerebellar artery was clearly verified to be compressing the glossopharyngeal nerve and then was safely and completely moved and fixed to the dura mater by the sling retraction technique to effect decompression. No patient has since experienced any further pain or permanent neurological deficit after surgery. TECHNICAL ADVANTAGE: The transcondylar fossa approach is one of the lateral approaches which is different from the transcondylar approach. In this approach, the posterior part of the jugular tubercle is extradurally removed without injuring the atlanto-occipital joint. The entire course of the cisternal portion of the glossopharyngeal nerve can be sufficiently seen with gentle retraction of the cerebellar hemisphere, when using this approach.

CONCLUSION

This approach makes the MVD for GPN both effective and safe.

Transcerebellomedullary fissure approach with special reference to methods of dissecting the fissure

OBJECT

The purpose of the present study was to refine the transcerebellomedullary fissure approach to the fourth ventricle and to clarify the optimal method of dissecting the fissure to obtain an appropriate operative view without splitting the inferior vermis.

METHODS

The authors studied the microsurgical anatomy by using formalin-fixed specimens to determine the most appropriate method of dissecting the cerebellomedullary fissure. While dissecting the spaces around the tonsils and making incisions in the ventricle roof, the procedures used to expose each ventricle wall were studied. Based on their findings, the authors adopted the best approach for use in 19 cases of fourth ventricle tumor. The fissure was further separated into two slit spaces on each side: namely the uvulotonsillar and medullotonsillar spaces. The floor of the fissure was composed of the tela choroidea, inferior medullary velum, and lateral recess, which form the ventricle roof. In this approach, the authors first dissected the spaces around the tonsils and then incised the taenia with or without the posterior margin of the lateral recess. These precise dissections allowed for easy retraction of the tonsil(s) and uvula and provided a sufficient view of the ventricle wall such that the deep aqueductal region and the lateral region around the lateral recess could be seen without splitting the vermis. The dissecting method could be divided into three different types, including extensive (aqueduct), lateral wall, and lateral recess, depending on the location of the ventricle wall and the extent of surgical exposure required.

CONCLUSIONS

When the fissure is appropriately and completely opened, the approach provides a sufficient operative view without splitting the vermis. Two key principles of this opening method are sufficient dissection of the spaces around the tonsil(s) and an incision of the appropriate portions of the ventricle roof. The taenia(e) with or without the posterior margin of the lateral recess(es) should be incised.

Effective methylprednisolone dose in experimental crescentic glomerulonephritis

Pulse methylprednisolone (MP) therapy improves the prognosis of crescentic glomerulonephritis, but the optimal dose is uncertain. We reported previously that treatment with MP at a dose of 30 mg/kg reduces glomerular crescents and infiltrating mononuclear cells and ameliorates the clinical abnormalities in an animal model of crescentic glomerulonephritis. In the present study, we assessed MP dose requirement for these beneficial effects in correlation with the effect on gene expression of chemokines, potential molecules responsible for recruitment and activation of leukocytes. Animals were treated with MP, 5 to 30 mg/kg/d, for 4 consecutive days after cellular crescents had been formed diffusely. The level of crescents and numbers of glomerular and interstitial monocytes/macrophages and T lymphocytes were reduced significantly by 5 mg/kg of MP, but maximal effect was obtained by 30 mg/kg of MP. Urinary protein was reduced significantly in a 30-mg/kg group but not in other groups. The gene expression of chemokines, MCP-1, MCP-3, TCA3, MIP-1alpha, MIP-1ss, RANTES, and lymphotactin, was enhanced in this model and was inhibited strongly by 5 mg/kg of MP. These results indicate that MP reduces the number of infiltrating mononuclear cells and crescents in the rat model in a dose-dependent fashion and that, despite the strong inhibition of chemokine expression at a lower dose, the beneficial effect of MP is maximal at a dose of 30 mg/kg.

Purification, characterization and developmental expression of chick (Gallus domesticus) liver PSP protein

We have isolated a perchloric acid-soluble protein designated as C-PSP from the post-mitochondria supernatant fraction of chick liver. It is soluble in 5% perchloric acid and purified by ammonium sulfate, fractionation and CM-Sephadex chromatography. The C-PSP showed approximately 70% homology with PSP isolated from rat liver (L-PSP1) with its partial amino acid sequences. The protein has a molecular mass of approximately 14 kDa which was slightly higher than that of L-PSP1. It inhibited protein synthesis in a rabbit reticulocyte lysate system. C-PSP was mainly expressed in liver and kidney and was also expressed in intestine, gizzard, glandular stomach, heart, brain and spleen though its expression was low. The expression of C-PSP in liver increased gradually from the 1st day to the 2nd week and it remained almost the same until the 13th week. C-PSP was also found in day 8 chick embryonic tissues. Interestingly, we found that C-PSP was expressed as a differentiation-dependent manner in the nervous cells of chick embryos. Thus, our findings are the first report on the presence of a PSP in avian tissues which may be involved in the regulation of cellular growth and differentiation.

Characterization of recombinant human adipocyte-derived leucine aminopeptidase expressed in Chinese hamster ovary cells

Adipocyte-derived leucine aminopeptidase (A-LAP) is a recently identified novel member of the M1 family of zinc-metallopeptidases. Transfection of the A-LAP cDNA into COS-7 cells resulted in the secretion of the enzyme. In this study, recombinant A-LAP was expressed in Chinese hamster ovary cells, purified to homogeneity and its enzymatic properties were characterized. The purified enzyme was active towards a synthetic substrate, L-leucyl-p-nitroanilide, yielding a V(max) of 3.55 micromol/min/mg and a K(m) of 1.28 mM, and was shown to be a monomeric protein with molecular mass of 120 kDa in solution. By monitoring the sequential N-terminal amino acid liberation, it was found that the enzyme hydrolyzes a variety of bioactive peptides, including angiotensin II and kallidin. Immunohistochemical analysis indicated that the enzyme is expressed in the cortex of the human kidney, where tissue kallikrein is localized. Taken together, these results indicate that A-LAP possesses a broad substrate specificity towards naturally occurring peptide hormones and suggest that it plays a role in the regulation of blood pressure through the inactivation of angiotensin II and/or the generation of bradykinin in the kidney.

Purification, characterization and differentiation-dependent expression of a perchloric acid soluble protein from rat kidney

We have recently reported the presence of a novel perchloric acid soluble protein in rat liver (PSP1) that inhibits cell-free protein synthesis in a rabbit reticulocyte system. While studying the perchloric acid soluble proteins from different tissues of rats, we found that the kidney protein cross-reacted with antibody against the PSP1. In this investigation, we have purified a perchloric acid soluble protein from the rat kidney and studied its characterization and expression. The protein extracted from the postmitochondrial supernatant fraction with 5% perchloric acid was purified by ammonium sulfate fractionation and CM-Sephadex chromatography. By immunoscreening with the rabbit antisera against the PSP1, we detected a cDNA that contained an open reading frame of 411 bp, encoding a 137 amino-acid protein with a molecular mass of 14,149 daltons. The deduced amino acid sequence was completely identical with that of PSP1 from rat liver. The perchloric acid soluble protein from rat kidney (K-PSP1) also inhibited cell-free protein synthesis in the rabbit reticulocyte lysate system in a different manner than RNase A. Immunohistochemistry showed that the expression of K-PSP1 increased from fetal 17th day to postnatal 4th week, and it remained almost the same until the 7th week of postnatal age. Furthermore, the expression of K-PSP1 in the kidney of the nephrotic rat model was shown to be differentiation dependent. On the other hand, the expression of K-PSP1 in renal tumor cells was downregulated as compared with intact tissue. These results suggest that the expression of K-PSP1 is regulated in a differentiation-dependent manner in the kidney.

Successful neuroendoscopic third ventriculostomy for hydrocephalus and syringomyelia associated with fourth ventricle outlet obstruction. Case report

The authors report the use of neuroendoscopic third ventriculostomy to treat successfully both hydrocephalus and syringomyelia associated with fourth ventricle outlet obstruction. A 27-year-old woman presented with dizziness, headache, and nausea. Magnetic resonance (MR) imaging demonstrated dilation of all ventricles, downward displacement of the third ventricular floor, obliteration of the retrocerebellar cerebrospinal fluid (CSF) space, funnellike enlargement of the entrance of the central canal in the fourth ventricle, and syringomyelia involving mainly the cervical spinal cord. Cine-MR imaging indicated patency of the aqueduct and an absent CSF flow signal in the area of the cistema magna, which indicated obstruction of the outlets of the fourth ventricle. Although results of radioisotope cisternography indicated failure of CSF absorption, neuroendoscopic third ventriculostomy completely resolved all symptoms as well as the ventricular and spinal cord abnormalities evident on MR images. Neuroendoscopic third ventriculostomy is an important option for treating hydrocephalus in patients with fourth ventricle outlet obstruction.

Transient and sequential expression of chemokine mRNA in glomeruli in puromycin aminonucleoside nephrosis

Chemokines are a large family of low-molecular-weight proinflammatory cytokines that stimulate recruitment of leukocytes. We previously reported that among six chemokines, the expression of mRNAs for MCP-1, MCP-3, TCA3, and MIP-1alpha, but not for MIP-1beta and RANTES, was markedly elevated in the renal cortex of rats with puromycin aminonucleoside induced nephrosis. In this study we have determined the glomerular expression of the chemokine mRNAs in this model using quantitative competitive reverse-transcriptase polymerase chain reaction. After an injection of puromycin aminonucleoside, the number of monocytes/macrophages and CD4+ and CD8+ cells markedly increased by day 5 and increased thereafter until day 10. The levels of mRNAs for MCP-1, MCP-3, and lymphotactin increased on day 5 and returned to their normal levels by day 7. The level of TCA3 mRNA increased on day 3, and that of MIP-1alpha mRNA increased on day 7, but both returned to their normal levels within 2 days. No increase in the mRNAs of MIP-1beta or RANTES was observed until day 10. These results indicate that the expression pattern of the chemokine mRNAs in glomeruli resembles that in renal cortex, but is more transient and sequential.

[Infratemporal fossa approach for mid-skull base lesion: its usefulness, surgical anatomy, and intraoperative device]

The usefulness of the infratemporal fossa type C approach is reported through a presentation of a case of clival chordoma, which was successfully treated by this approach. Although it is complicated and includes some demerits, this approach gives a shorter and wider access to mid-skull base pathology than other approaches. Among the demerits, deformity of the temporal region caused by extensive drilling of the bone could be minimized by cosmetic mastoidectomy, which was first applied during this approach by the authors. The surgical anatomy for this approach is demonstrated using a cadaver specimen.

Therapeutic effect of glucocorticoid on experimental crescentic glomerulonephritis

Crescentic glomerulonephritis shows active and progressive glomerular changes with rapid deterioration in kidney function. A large dose of glucocorticoid (pulse therapy) is clinically used for the treatment, but its efficacy has not been fully estimated. In this study we assessed the therapeutic effect of a large dose of methyl-prednisolone (MP) on a rat model of crescentic glomerulonephritis that had been induced in WKY rats by an injection of anti-glomerular basement membrane antibody. The infiltration of CD8+ cells and monocytes was manifest by day 3, proteinuria appeared on days 4 and 5, and cellular crescents were diffusely formed by day 7. The gene expression of MCP-1, a chemokine for monocytes and T lymphocytes, was enhanced within 4 hours and peaked on day 3. Daily administration of MP (30 mg/kg/d) from day 3 through day 6 reduced the gene expression of MCP-1 and the numbers of glomerular leukocytes and largely prevented both crescent formation and proteinuria. When daily MP treatment started on day 7, the numbers of glomerular CD8+ cells and monocytes, crescents, and urinary protein were significantly reduced by day 11. In addition, continuing treatment with a small dose of MP (3 mg/kg/d) begun on day 11 completely prevented the increase in blood urea nitrogen and serum creatinine levels. These results indicate that treatment with a large dose of MP histologically and clinically ameliorates crescentic glomerulonephritis in a rat model, supporting the efficacy of pulse MP therapy for the treatment of the disease in human subjects.

Huge hamartoma with inverted papilloma in the nasal cavity

We report clinical experience in managing a 46-year-old Japanese man with long-standing nasal obstruction resulting from a huge left nasal mass. Computed tomography, magnetic resonance imaging and biopsy were used to make a provisional diagnosis of inverted papilloma. The mass was resected via a frontal approach combined with rhinotomy. Histopathologic examination of the resected specimen was consistent with a hamartoma that included an inverted papilloma on a portion of its surface. In addition to being rare tumors in the nasal cavity, we believe that our patient's tumor the largest nasal hamartoma ever reported.

An indirect revascularization method in the surgical treatment of moyamoya disease--various kinds of indirect procedures and a multiple combined indirect procedure

The indirect non-anastomotic bypass procedures for moyamoya disease are herein reviewed, and our multiple combined indirect procedure, i.e. a fronto-parieto-temporal combined indirect bypass procedure, is also introduced. Direct procedures such as superficial temporal artery-middle cerebral artery anastomosis are able to form collaterals with a high reliability, but these procedures are often difficult to technically perform in small children, and complications, when they occur, tend to be severe. Indirect procedures, such as encephalo-duro-arterio-synangiosis (EDAS), encephalo-myo-synangiosis (EMS), and encephalo-myo-arterio-synangiosis (EMAS) etc., are safe and easy and also successfully form collaterals especially in children with moyamoya disease. However, there are a few drawbacks with such procedures. They do not always form sufficient collaterals. The area where the original EDAS using the posterior branch of the superficial temporal artery can be done is also limited. Moreover, because the area covered by each single procedure is small, the collateral formation obtained by a single procedure is not always satisfactory. For these reasons we developed a fronto-temporoparietal combined indirect bypass procedure for child patients in order to overcome these problems. This multiple combined indirect procedure can cover a wider area of the ischemic brain through the EMAS in the frontal and the EDAS and EMS in the temporo-parietal regions. It is also safe and easy to perform, and one or two of these three procedures form sufficient collaterals with a relatively high reliability. This technique is described and the results are presented.

Surgery of angiomas in the brainstem with a stress on the presence of telangiectasia

This report deals with the surgery of angiomas other than arteriovenous malformation in the brainstem. The surgical cases were three cavernomas, two telangiectasias, and two venous malformations. We performed surgery when an angioma bled and the resulting hematoma was situated near the surface of the brainstem or the fourth ventricle. The cases were operated on at the subacute or chronic stages after hemorrhage. Although a magnetic resonance (MR) image showed a subacute or chronic localized hematoma with a low intensity rim, the case was not always a cavernoma, but a telangiectasia. Cavernomas could be totally removed, but telangiectasia could not. In the cases of medullary venous malformation the diagnosis was obtained radiologically, and when the hematoma was large, only hematoma evacuation was performed. In all cases the postoperative Karnofsky scores were improved or unchanged. Postoperative rebleeding in the hematoma cavity continued insidiously in a case of telangiectasia. The abnormal vessels of telangiectasia in the brainstem were preoperatively not visualized by cerebral angiography or MR imaging, but became visualized by enhanced MR imaging after evacuation of hematoma in two cases. It is stressed that an angioma with a hematoma intensity core surrounded by a low intensity rim on MR images is not always a cavernoma, but possibly is a telangiectasia.

Analysis of the fatty acid components in a perchloric acid-soluble protein

We had previously found that a perchloric acid-soluble protein (PSP1) occurs in rat liver, and that this novel protein inhibits protein synthesis in a rabbit reticulocyte lysate system (T. Oka, H. Tsuji, C. Noda, K. Sakai, Y.-H. Hong, I. Suzuki, S. Muñoz, Y. Natori, J. Biol. Chem. 270 (1995) 30060-30067). In the present study, we analyzed lipid components bound to PSP1. Native PSP1 was purified from rat liver using Sephadex G-75, DE-52 cellulose and IgGPSP-affinity chromatography, and the lipid components were extracted. The components obtained from the purified PSP1 were shown to be free fatty acids by thin-layer chromatography. By GC-MS, six major fatty acids were identified as 14:0, 16:0, 18:0, 18:1, 18:2 and 20:4. 1 mol of PSP1 contained 1.26 mol of total fatty acid components. The fatty acid-binding assay of PSP1 showed that the Bmax was 1.25 mol fatty acid/mol PSP1 and the Kd value for palmitic acid was 6.03 microM. The concentration of PSP1 mRNA in rat liver increased 2.3-fold by the administration of peroxisome proliferator, bezafibrate. These findings show that PSP1 is a fatty acid-binding protein-like protein, which is involved in the intracellular metabolism of fatty acid and is quite different from the known fatty acid-binding proteins.

Induction of cytokines in a human colon epithelial cell line by Shiga toxin 1 (Stx1) and Stx2 but not by non-toxic mutant Stx1 which lacks N-glycosidase activity

Stx1 and Stx2 produced by Shiga toxin-producing Escherichia coli are cytotoxic due to their N-glycosidase activity on 28S rRNA. In this study, we have shown that proinflammatory cytokine mRNAs, especially IL-8, were induced by Stx1 and Stx2 in Caco-2 cells. A non-toxic mutant of Stxl which lacks N-glycosidase activity did not induce cytokine mRNAs. IL-8 production at the protein level was enhanced by Stx1 and Stx2, but not by the mutant Stx1. These results demonstrate that Shiga toxins induce expression and synthesis of cytokines in Caco-2 cells and their N-glycosidase activity is essential for the induction.

[Clinical experience of image-guided neurosurgery with a frameless navigation system (StealthStation)]

We have applied the frameless navigation system (StealthStation) to various neurosurgical procedures to examine its usefulness. The system consists of a UNIX based workstation that creates triplanar and 3-dimensional images; an infrared optical digitizer with camera array; a reference-light-emitting diode (LED) array (e.g., reference array); and pointer probe modified by the addition of LEDs. This system was used to assist in placing a minimal skin incision and craniotomy in 4 cases, to determine the tumor/brain interface in 2 cases, to target the subcortical lesion in one case, and to correlate bony structure with a skull base tumor in 3 cases. The combined use with magnetic source imaging of the somatosensory cortex allowed a fast orientation of eloquent areas in 2 cases with peri-Rolandic tumor. This system, thus, was proved to be a useful adjunct to open-tumor biopsy or resection.

Gene expression of CC chemokines in experimental acute tubulointerstitial nephritis

The infiltration of mononuclear leukocytes into glomeruli or the interstitium is a feature in most forms of glomerular diseases. CC chemokines, mostly chemoattractants for mononuclear leukocytes, are molecules that are potentially responsible for the recruitment of these cells in the kidney. We previously reported that the gene expression of six CC chemokines-MCP-1, MCP-3, MIP-1alpha, MIP-1beta, RANTES, and TCA3-was enhanced in a rat model of crescentic glomerulonephritis, the most severe form of glomerulonephritis. In this study we analyzed their gene expression in a model of another type of kidney disease, acute nephrosis accompanied by tubulointerstitial lesions, which is induced by an injection of puromycin aminonucleoside. Because leukocyte infiltration in this model is much more prominent in the interstitium than in glomeruli, we analyzed their gene expression in the renal cortex. On day 3, when the level of urinary protein was slightly but significantly increased but the number of interstitial leukocytes was unchanged, the enhanced expression of mRNAs for MCP-1, MCP-3, and TCA3 was observed. On day 5, the numbers of interstitial monocytes and lymphocytes significantly increased, and the levels of the mRNA expression of the above chemokines were still higher than the control animals, whereas the levels of mRNAs for MIP- 1alpha, MIP-1beta, and RANTES were not higher or were only slightly higher than the control ones. These results suggest that multiple CC chemokines may play a role in the recruitment of leukocytes in this model and that the expression pattern of CC chemokines depends on the type of kidney injury.

Production of functional rat liver PSP protein in Escherichia coli

An efficient Escherichia coli expression system for the production of a perchloric acid-soluble protein (PSP) has been constructed. Complementary DNA encoding PSP was inserted into an inducible bacterial expression vector pGEX-4T-1. After the plasmid introduced into E. coli was expressed by isopropyl 1-thio-beta-D-galaetopyranoside (IPTG), the recombinant product was purified by glutathione-Sepharose 4B affinity chromatography. The purified product showed the expected NH2-terminal sequence, but the translation inhibitory activity of this product was 10 times lower compared with that of authentic PSP isolated from rat liver.

A historical cohort mortality study of workers exposed to asbestos in a refitting shipyard

To investigate the risks of developing asbestos-related diseases we conducted a historical cohort mortality study on 249 ship repair workers (90 laggers and 159 boiler repairers) in a single U.S. Navy shipyard in Japan. We successfully identified the vital status of 87 (96.7%) laggers and 150 (94.3%) boiler repairers, and, of these, 49 (56.3%) and 65 (43.3%) died, respectively, during the follow-up period from 1947 till the end of 1996. Our in-person interviews with some of the subjects clarified that asbestos exposure was considered to be substantially high in the 1950-60s, decreased thereafter gradually but remained till 1979 in the shipyard. The laggers, who had handled asbestos materials directly, showed a significantly elevated SMR of 2.75 (95% C.I.: 1.08-6.48) for lung cancer. The risk developing the disease was greater in the laggers after a 20-year latency (SMR = 3.42). Pancreatic cancer yielded a greater SMR than unity (7.78, 90% C.I.: 2.07-25.19) in a longer working years group. Four laggers died from asbestosis. The boiler repairers, who had many chances for secondary exposure to asbestos and a few for direct exposure, showed no elevation of the SMR of lung cancer overall, but there was a borderline statistically significant SMR of 2.41 (90% C.I.: 1.05-5.45) in a longer working years group. One boiler repairer died from mesothelioma and four from asbestosis.

Multiple combined indirect procedure for the surgical treatment of children with moyamoya disease. A comparison with single indirect anastomosis with direct anastomosis

Considering three different bypass procedures now in use, (single indirect nonanastomotic bypass procedure, multiple combined indirect (MCI) nonanastomotic procedure and direct anastomosis), the authors attempted to identify the most appropriate bypass procedure for treating ischemic-type moyamoya disease in children.

The authors performed three procedures (the original encephaloduroarteriosynangiosis [EDAS] alone, the frontotemporoparietal combined indirect bypass procedure, and the superficial temporal artery-middle cerebral artery [STA-MCA] anastomosis with encephalomyosynangiosis [EMS]) on 72 hemispheres in 50 patients with pediatric moyamoya disease. Analyses were then performed to compare postoperative collateral vessel formation found on angiograms, complications, and clinical improvements. Postoperative collateral formations were observed in more than two-thirds of the MCA distribution after the EDAS alone, the MCI procedure, and the direct anastomosis in 44%, 52%, and 74% of the surgically treated hemispheres, respectively. In addition, frontal encephalomyoarteriosynangiosis of the MCI bypass procedure formed collateral vessels of the anterior cerebral artery distribution in 94% of the treated hemispheres. Postoperatively, clinical symptoms resolved in 56%, 63%, and 74% of the treated sides 1 year after EDAS alone, MCI procedure, and the direct anastomosis, respectively. One patient suffered a minor stroke after EDAS alone, two patients developed epidural hematomas after the MCI procedure, and one patient suffered a major stroke and one patient a minor stroke after undergoing direct anastomosis.

The direct anastomosis procedure was found to result in the best postoperative collateral vessel formation and clinical improvement. However, the single and multiple combined indirect nonanastomotic bypass procedures were found to be safer than direct anastomosis. Furthermore, the frontotemporoparietal combined indirect bypass procedure caused the formation of collateral circulation not only in the MCA but also in the ACA distribution. Based on analysis of these findings, the authors recommend the MCI procedure as the appropriate surgical procedure in the treatment of children with moyamoya disease, although the best treatment is the STA-MCA anastomosis with EMS when feasible.

Expression of lymphotactin mRNA in experimental crescentic glomerulonephritis

Lymphotactin (LTN) is the sole member of C chemokine, the third subfamily of chemokines. LTN has been shown to be a chemoattractant specific for CD8+ cells and/or natural killer (NK) cells, and to be produced by CD8+ T cells, NK cells, and mast cells. However, there have been no reports describing its expression in clinical or experimental models of diseases so far. Since glomerular infiltration of CD8+ cells is prominent in an animal model of crescentic glomerulonephritis induced in WKY rats by an injection of anti-glomerular basement membrane antibody, we investigated the gene expression of LTN in this model. LTN mRNA was not detected in normal glomeruli but was detected at 0.5 h after the antibody injection, which detection preceded the infiltration of CD8+ cells. The expression of LTN mRNA peaked on day 3 and decreased thereafter. We next studied the expression of LTN mRNA in cultured glomerular and vascular cells, and found that glomerular mesangial and vascular endothelial cells could express LTN mRNA when stimulated with IL-1beta. These results indicate that the gene expression of LTN is enhanced in the animal model of glomerulonephritis and that intrinsic renal cells are the potential source of the gene expression of LTN in the kidney.

A simple procedure for the isolation of rat kidney lysosomes

BACKGROUND

A procedure for the isolation of highly purified lysosomes from normal rat kidney is described.

METHODS

The method depends on the swelling of mitochondria when the postnuclear supernatant fraction is incubated with 2 mM Ca2+. The lysosomes can then be separated from the swollen mitochondria by Percoll density gradient centrifugation.

RESULTS

The lysosomal fraction obtained by our method was enriched more than 30-fold in terms of marker enzymes with a yield of about 11%. Electron microscopic examination and the measurement of the activities of marker enzymes for various subcellular organelles indicated that our lysosomal preparation was essentially free from contamination by other organelles.

CONCLUSION

We believe that this procedure for isolating kidney lysosome will be useful in the study of the mechanisms of specific modification, processing and catabolism of proteins.

cDNA cloning, expression, and characterization of the human bifunctional ATP sulfurylase/adenosine 5'-phosphosulfate kinase enzyme

A cDNA encoding the human bifunctional ATP sulfurylase/adenosine 5'-phosphosulfate (APS) kinase was cloned and sequenced. The enzyme contains an APS kinase domain in its N-terminal portion and an ATP sulfurylase domain in its C-terminal portion. Recombinant full-length enzyme and its constituent APS kinase and ATP sulfurylase domains were individually expressed, purified, and shown to have their respective enzymatic activities.

Characterization of fibronectin-related substances in normal and passive Heymann nephritis rats

The excretion mechanism of fibronectin (FN)-related substances into the urine of normal and passive Heymann nephritis (PHN) rats was studied using enzyme immunoassay and immunoblot analysis. In normal rats, a small amount (0.20+/-0.067 microg/d) of FN-related substances, composed of 55- and 65-kDa FN fragments derived from the central cell-binding (Cell) domain of FN, were constitutively excreted into the urine. When PHN was induced in rats by the injection of an anti-Fx1A antibody, an increased excretion (4.96+/-3.51 microg/d) of intact FN and large (Mr > 100-kDa) FN fragments containing the Cell and the other functional domains were seen. The PHN induction also caused the appearance of a considerable amount of Cell domain-containing FN fragments in plasma. Both the renal cortex homogenates of normal and PHN rats were capable of degrading plasma FN to generate the Cell domain-containing large FN fragments. Degradation of FN by the renal cortex homogenate was shown to be due to metal and/or thiol proteinase(s). These results suggest that the PHN-induced urinary excretion of FN fragments may be due to the degradation of plasma FN by renal proteinases that may be leaked upon PHN induction.

Operative approaches to the pineal region tumors

Until the introduction of microsurgery, the surgical treatment of pineal region tumors had very poor results with high mortality and morbidity. However, there have been remarkable improvements with modern surgical technology and advanced knowledge. Now the main surgical approaches to pineal region tumors are the occipital transtentorial approach and the infratentorial supracerebellar approach. Recently the neuroendoscopic approach has been added. The surgical approach and any supplementary treatment should be selected in each case according to the nature of the individual tumor. The forms of treatment practiced by ourselves, including neuroendoscopic surgery, are presented, and the surgical treatments now applied are discussed.

Micro-anatomical study of the carotid cave

The surgical treatment of aneurysms located in the carotid cave is often hazardous and difficult. We studied the micro-anatomy of the carotid cave and its neighbourhood by microscopic observation and histological examination using 50 sides from 25 autopsy cases. The carotid caves were found in 34 out of the 50 sides (68%) examined and were usually located in the posteromedial aspect of the carotid dural ring. They were classified into three types according to the topographic micro-anatomy: the slit-type (17/50, 34%) which showed a small, thin recess of the dura mater with fine connective tissue loosely adhered to the carotid wall; the pocket-type (12/50, 24%) which had a definite dural pouch with the apex attached to the vessel wall; and the mesh-type (5/50, 10%) which formed a slit- or pocket-type dural cave covered with a mesh-like dural roof. The remaining 16 sides (32%) showed tight dural attachment without any caval structure around the dural ring. The posteromedial portion of the carotid dural ring had no contact with any bony structure, and this distinct anatomical feature thus appear to facilitate the formation of the carotid cave. Furthermore, the availability of this potential space and the closely situated origin of the superior hypophyseal artery as well as the haemodynamic effect of the internal carotid artery may allow the development of the carotid cave aneurysm.

'Angiographic moyamoya' its definition, classification, and therapy

Are there any differences between probable Moyamoya disease and unilateral Moyamoya disease? What kinds of differences exist between definite and probable Moyamoya disease? Furthermore, according to the diagnostic criteria of Moyamoya disease, patients with systemic disorders and angiographic features similar to those of Moyamoya disease can not be diagnosed as Moyamoya disease. How should we call these? Such patients have been reported as 'Moyamoya syndrome,' 'quasi-Moyamoya disease', 'akin-Moyamoya disease'. etc. These variations of terminology including unilateral or probable Moyamoya disease have thus led to as state of confusion. In this study the previously reported cases in the literature were surveyed to clarify how these terms have been used and how we should use them correctly in the future. Since the diagnostic criteria of this disease are mainly based on angiographic findings, the term Moyamoya 'syndrome' should not be used. A unilateral involvement without any known cause should be called 'probable.' Because some systemic diseases commonly associated with Moyamoya disease might be genetically linked, it is better to avoid using such vague expressions as 'quasi', 'akin', or 'pseudo.' There might be a coexistence of two diseases. It is therefore better to simply state that the angiographic findings are similar to Moyamoya disease, or a systemic disease with 'angiographic Moyamoya' until the etiology of the Moyamoya disease is clarified.

Vitamin B6 suppresses growth and expression of albumin gene in a human hepatoma cell line HepG2

The effect of vitamin B6 on the growth of a human hepatoma cell line HepG2 in culture was studied. The growth of HepG2 cells and protein synthesis were almost completely inhibited in medium supplemented with 5 mM pyridoxine. Pyridoxal was as effective as pyridoxine, but pyridoxamine showed no inhibitory action. The growth inhibition of HepG2 cells by pyridoxine was accompanied by a marked inhibition of secretion of plasma proteins, particularly albumin. Northern blot analysis of albumin mRNA showed that pyridoxine caused a rapid decrease in the expression of albumin gene. The electron-microscopic examination of pyridoxine-treated HepG2 cells revealed a smoothing of nuclear membrane, a decrease in the number of nucleoli, and an appearance of aggregated heterochromatin structures. These morphological features are compatible with the depressed transcriptional activity in the pyridoxine-treated cells. The mechanism by which vitamin B6 exerts its inhibitory effect was discussed in terms of our recent finding that vitamin B6 modulates expression of albumin gene by inactivating tissue-specific DNA-binding proteins. Binding of pyridoxal phosphate with tissue-specific transcription factors may reduce the capacity of these factors to interact with the regulatory region of albumin gene, resulting in the inhibition of the gene expression.

Effect of varying amino acid levels on protein metabolism in nephrotic rats during total parenteral nutrition

In an attempt to determine appropriate diet in nephrotic syndrome, nephrotic rats, induced by puromycin aminonucleoside, were nourished by total parenteral nutrition fluid containing the same energy, but three different levels (1.65, 3.3, and 6.6%) of amino acids for 7 d. The fractional rate of total protein synthesis in the liver was determined by injecting a flooding dose of [3H]phenylalanine. The proportion of newly synthesized proteins retained and exported by the liver was estimated by injecting a tracer dose of [14C]leucine and then measuring the protein radioactivity remaining in the liver and present in the plasma after secretion was completed. Nephrotic animals synthesized more protein than control animals. Although the absolute synthesis rates of total protein in liver were increased with increasing amino acid administration, the absolute rates of synthesis of albumin were higher in the 3.3% group than in the other groups in nephrotic rats. However, kidney protein synthesis in nephrotic rats was higher in the 1.65% group than in the 3.3% group. Interestingly, the 3.3% group revealed the smallest urinary excretion of total protein and albumin. In addition, in the 3.3% group, plasma concentrations of total protein and albumin were higher, and plasma concentrations of total cholesterol and triglyceride were lower than in other groups. It was concluded that the 3.3% group, corresponding to a normal protein diet, has the greatest salutary effect on urinary protein excretion, followed by protein and lipid metabolism, in nephrotic rats. Not only protein intake but also the energy:protein ratio are important for diet therapy in nephrotic animals. The technique of total parenteral nutrition may be useful in defining the factors involved in glomerular permeability or permselectivity and intracellular protein metabolism.

Gene expression of CC chemokines in experimental crescentic glomerulonephritis (CGN)

CGN is a rapidly progressive glomerular disease. Monocytes/macrophages are frequently observed in glomeruli in cases of CGN and they are considered to play a crucial role in the pathogenesis of this disease. We described previously the glomerular expression of monocyte chemoattractant protein-1 (MCP-1), which is a potent chemoattractant for monocytes and a member of CC chemokine family, in an experimental model of CGN. In the present study we investigated the expression of mRNAs for other CC chemokines, namely, MCP-3, macrophage inflammatory protein-1alpha (MIP-1alpha), MIP-1beta, RANTES and TCA3, all of which are chemotactic for monocytes, in the CGN model. First, we established a reverse transcriptase-polymerase chain reaction (RT-PCR) method by which mRNA for each of the CC chemokines could be amplified separately, and then we measured the levels of the expression of mRNAs for the chemokines in diseased glomeruli at several time points after induction of CGN. The mRNAs for all CC chemokines examined were expressed in glomeruli of rats with CGN. Moreover, induction of the gene expression of MIP-1alpha and MIP-1beta seemed to occur earlier than that of the others. CC chemokines may contribute to the recruitment and activation of monocytes in CGN, and each individual CC chemokine may play an overlapping but distinct role in the pathogenesis of this disease.

Production of monocyte chemoattractant protein-1 by cultured glomerular epithelial cells: inhibition by dexamethasone

Glomerular epithelial cells (GECs) have been shown to be one class of target cells in immunological and nonimmunological glomerular injury of glomerulonephritis, some cases of which are accompanied by infiltration of glomeruli by monocytes/macrophages. In this study we tested whether GECs in culture produce monocyte chemoattractant protein-1 (MCP-1), a potential molecule responsible for monocyte recruitment in inflammation, and whether the production is inhibited by glucocorticoid. GECs were obtained from outgrowth of rat glomeruli. Levels of MCP-1 mRNA and protein were determined by Northern blot analysis and ELISA, respectively. Northern blot analysis revealed the expression of MCP-1 mRNA in cytokine-treated GECs. The expression of MCP-1 mRNA was inhibited by dexamethasone. Quantitative analysis by ELISA confirmed the production of MCP-1 protein by GECs and the inhibitory effect of dexamethasone. These results indicate that cytokine-treated GECs produce and secrete MCP-1 and that the MCP-1 production is inhibited by dexamethasone. We suggest that MCP-1 produced by GECs may play a role in the recruitment of monocytes/macrophages in glomerulonephritis and that the therapeutic effect glucocorticoid on the disease might include the inhibition of the production of MCP-1.

Endocytosis of serum albumin in regenerating rat liver

Lysosomes, isolated from rat liver after 70% partial hepatectomy (PHX), were found, by Western blotting, to contain a considerable amount of serum albumin. The level of intralysosomal serum albumin after PHX showed biphasic patterns: it increased immediately after PHX, peaked at 30 min, rapidly declined within a few hours, rose again with a peak at 15 hr, and gradually declined thereafter. At 15 hr after PHX, the content of lysosomal proteins in the liver increased to twice the level of unoperated control, and the electron-microscopic observation of the isolated lysosomes revealed numerous large membrane-delimited structures with ground substances of variable electron opacities. The increase in the intralysosomal serum albumin at 30 min and 15 hr was accompanied by changes in the buoyant densities of endosomes in Percoll density gradients. At both time points, the density profiles of endosomes isolated from hepatectomized rats shifted to the denser direction, suggesting that PHX activates fusion and/or maturation of endosomes. Formaldehyde-treated bovine serum albumin is known to be taken up by the liver by receptor-mediated endocytosis. The uptake of the modified heterologous albumin was shown to be activated as early as 30 min after PHX. Both the uptake of serum albumin into lysosomes and the shift of buoyant density profile of endosomes after PHX were inhibited by the administration of adrenergic receptor antagonists, particularly by the alpha r-antagonist prazosin. Further, the concentration of catecholamines in rat serum, particularly that of norepinephrine, was found to increase immediately after PHX, relative to that in serum from sham-operated rats. These results suggest that the elevation of serum norepinephrine levels after PHX activates endocytosis and facilitates delivery of endocytosed serum albumin to lysosomes, where albumin is digested to yield amino acids for possible use in protein synthesis during liver regeneration.

Expression of monocyte chemoattractant protein-1 in experimental crescentic glomerulonephritis in rats

Crescentic glomerulonephritis (CGN) is a rapidly progressive glomerular disease that is usually associated with a poor prognosis. Monocytes/macrophages are frequently observed in glomeruli in cases of CGN, and they are considered to play a crucial role in the pathogenesis of this disease. In this study we analyzed the glomerular expression of monocyte chemoattractant protein-1 (MCP-1), a potent chemoattractant for monocytes, in an experimental model of CGN. A model of the disease was induced in the WKY strain of rats by intravenous injection of antiserum raised against glomerular basement membranes. Accumulation of monocytes/macrophages in glomeruli was observed 4 hours after the injection of antiserum. Northern blot analysis showed that the expression of mRNA for MCP-1 was enhanced within 4 hours, peaked on day 3--when it was 60 times that in the control--and then declined. Immunostaining with MCP-1-specific antibody revealed the expression of MCP-1 protein in the diseased glomeruli but not in control glomeruli. Quantitative analysis of glomerular MCP-1 protein by enzyme-linked immunosorbent assay revealed a level 46 times that in the control in reflecting the increase in mRNA for MCP-1. These results indicate that glomeruli of rats with CGN produce MCP-1, which may play an important role in the pathogenesis of glomerular inflammation and crescent formation in CGN.

Cloning and sequencing of cDNA encoding 4-aminobenzoate hydroxylase from Agaricus bisporus

A cDNA clone encoding 4-aminobenzoate hydroxylase (EC 1.14.13.27) has been isolated using a probe prepared by PCR on the basis of partially determined amino acid sequences of the enzyme. The cDNA contained 1380-base pair open reading frame encoding 460 amino acid residues (M(r) 50974), 14-base pair 5'-untranslated region and 123-base pair 3'-untranslated region including a poly(A) tail of 20 nucleotides. All of the partially determined amino acid sequences were shown to be included in the deduced amino acid sequence. Homology analyses showed that the two regions on the enzyme share other flavoproteins such as salicylate hydroxylase and p-hydroxybenzoate hydroxylase.

Detection of N-acetylgalactosaminyltransferase mRNA which determines expression of Sda blood group carbohydrate structure in human gastrointestinal mucosa and cancer

The Sda blood group carbohydrate structure, GalNAcbeta1-4[NeuAcalpha2-3]Galbeta1-4GlcNAc-R, is expressed on glycolipid and glycoprotein in human gastrointestinal mucosa. The expression of the Sda determinant dramatically decreases in cancer tissue. The activity of the beta1,4N-acetylgalactosaminyltransferase (Sda-GalNAcT), which transfers GalNAc to NeuAcalpha2-3Galbeta1-4Glc(NAc)-R, correlates with the expression of the Sda immuno-epitope. From the total RNA fraction of human gastric mucosa, we have amplified a cDNA segment by reverse-transcription-polymerase-chain reaction (RT-PCR), using primers designed according to the cDNA sequence of a murine beta1,4GalNAcT which synthesizes the Sda determinant. An RT-PCR product of 390 bp shared 85% nucleotide identity with the murine Sda-related beta1,4GalNAcT. This RT-PCR product hybridized to a transcript in mRNA prepared from human gastric mucosa. In RT-PCR using specific primers to this PCR product, Sda-GalNAcT mRNA was detected in all samples of normal stomach and small intestine examined and the majority of normal colonic specimens. Six out of nine cases of gastric cancer, and 9 out of 13 cases of colonic cancer failed to produce the target DNA. These results correlate with the beta1,4GalNAcT activity measured in the same samples. In conclusion, a segment of the cDNA for betal,4GalNAcT which determines expression of the Sda carbohydrate structure was obtained, and reduced transcription of this beta 1,4GalNAcT resulted in the disappearance of the Sda epitope in gastrointestinal cancer.

Vitamin B6 deficiency accelerates metabolic turnover of cystathionase in rat liver

Although most of cystathionase was found to exist as an inactive apoenzyme in the liver of vitamin B6-deficient rats, the concentrations of the immunoreactive enzyme protein were virtually the same for control and vitamin B6-deficient livers. Under vitamin B6 deficiency, however, the rate of synthesis of cystathionase, measured by incorporation of labeled amino acid into the immunoprecipitated enzyme, was increased severalfold due to an increased level of cystathionase mRNA. Western blot analysis of lysosomal proteins showed that the amount of cystathionase in the lysosomes from the liver of vitamin B6-deficient rats was also increased severalfold. This observation suggests that lysosomes specifically recognize the apocystathionase for sequestration in preference to the holoenzyme. The present study provides the molecular basis for dual roles of vitamin B6 in controlling the metabolic turnover of cystathionase; it regulates synthesis of the enzyme by modulating the expression of cystathionase gene, and it regulates degradation of the enzyme by different susceptibilities of apo- and holoenzymes to lysosomal proteolysis.

Jak3 expression in glomerular epithelia of IgA nephropathy (IgA-N) patients

Jak3 is a member of the Janus kinase family which plays an important role in cytokine signal transduction. Jak3 associates the gamma(c) chain of receptors for IL-2, IL-4, IL-7, IL-9 and IL-15, and is essential for the signal transduction of these cytokines. We have isolated Jak3 kinase from renal mesangial cells and demonstrated the constitutive expression of Jak3 in glomeruli in vivo. To investigate the physiological and pathological role of Jak3 in glomeruli, we prepared anti-Jak3 antibody and analysed the localization of Jak3 in glomeruli of renal biopsy samples from various nephritis patients and normal subjects. Among 61 nephritis patients and four normal subjects investigated in the present study, Jak3 was selectively localized to glomerular epithelia of IgA-N patients (14/34 cases) and focal glomerulosclerosis patients (1/5 cases), but not detected in minimal changes (n = 6), membranous glomerulonephropathy (n = 7), crescentic glomerulonephritis (n = 4), lupus nephritis patients (n = 5), and normal subjects (n = 4). The intense immunoreactivity for Jak3 is significantly associated with the decrease in creatinine clearance (81.5 +/- 10.4 ml/min versus 104.3 +/- 29.6 ml/min; P < 0.05, Student's t-test) and the increase in level of serum creatinine (1.13 +/- 0.33 mg/dl versus 0.75 +/- 0.23 mg/dl; P < 0.01, Student's t-test) in IgA-N patients. Furthermore, gamma(c) chain was concomitantly expressed with Jak3 in glomerular epithelia in vivo and in vitro, suggesting that signal transduction via gamma(c)-Jak3 cascade may be involved in the pathogenesis of glomerular injury of IgA-N. Taken together with the recent findings that IL-4-secreting T lymphocytes in affected glomeruli injure glomerular epithelium, the responsiveness of glomerular epithelium for IL-4 may be pathologically enhanced in IgA-N.