Thymidylate synthase levels as a therapeutic and prognostic predictor in breast cancer

5-Fluorouracil (5-FU) is a commonly used adjuvant therapeutic drug in treating breast cancer. 5-FU is metabolically converted to 5-fluorouracil-2'-deoxyuridine-5'-monophosphate-(FdUMP) which is believed to inhibit DNA synthesis in neoplastic cells by forming a tightly bound ternary complex with thymidylate synthase (TS). In the present study, we examined the possible relationship between TS levels and clinico-pathologic and prognostic features in breast disease. Mean TS levels of 2.9 pmol/g, 6.1 pmol/g, and 23.1 pmol/g were obtained in cases of benign breast disease (3 cases), primary breast cancer (115 cases), and recurrent tumors (4 cases), respectively. In breast cancer, mean TS levels significantly correlated with S-phase fraction (SPF), DNA polymerase a and lymphatic invasion. Thus, TS levels in breast cancer significantly reflected cell proliferation and malignancy. Regarding the survival rate, patients with TS values above 10 pmol/g showed an unfavorable prognosis. The effectiveness of adjuvant 5-FU derivatives chemotherapy was reflected in a higher disease-free survival rate in node (+) cases showing TS levels between 5 and 10 pmol/g (p < 0.1), but not in node (-) cases. In conclusion, TS levels in neoplastic tissues of the breast were highest in recurrent tumors, followed by those in primary cancer, benign breast disease and in breast cancer which reflected proliferative activity. Breast cancers with extremely high TS levels were accompanied by an unfavorable prognosis; however, those with moderately high TS levels tended to respond to adjuvant chemotherapy with 5-FU derivatives.

J-104129, a novel muscarinic M3 receptor antagonist with high selectivity for M3 over M2 receptors

A new class of 4-acetamidopiperidine derivatives has been synthesized and investigated for human muscarinic receptor subtype selectivity. Introduction of a hydrocarbon chain of appropriate length into the piperidine nitrogen of the racemic N-(piperidin-4-yl)-2-cyclobutyl-2-hydroxy-2-phenylacetamide platform conferred up to 70-fold selectivity for human muscarinic M3 receptors over M2 receptors. Subsequent synthetic derivatizations resulted in highly potent M3 receptor antagonists with selectivity greater than two orders of magnitude for M3 over M2 receptors, from which the analogue 4r was selected. Preparation of both enantiomers of 4r led to the identification of (2R)-N-[1-(4-methyl-3-pentenyl)piperidin-4-yl]-2-cyclopentyl-2-hyd roxy-2-phenylacetamide (J-104129, (R)-4r), which exhibited 120-fold selectivity for M3 receptors (Ki = 4.2 nM) over M2 receptors (Ki = 490 nM). In isolated rat trachea, (R)-4r potently and specifically antagonized acetylcholine (ACh)-induced responses with a K(B) value of 3.3 nM. The highly subtype-selective profile was also seen in isolated rat tissue assays (50-fold) and in anesthetized rats (> 250-fold). Oral administration of J-104129 ((R)-4r) antagonized ACh-induced bronchoconstriction with an ED50 value of 0.58 mg/kg in rats. Thus, J-104129 ((R)-4r) may effectively facilitate bronchodilation in the treatment of obstructive airway disease.

Ascitic fluid of experimental severe acute pancreatitis modulates the function of peritoneal macrophages

Although the pathophysiology of acute pancreatitis appears to be greatly influenced by the production of ascites, little is known about the mechanism. To investigate the effects of pancreatitis-associated ascitic fluid (PAAF) on macrophage function, we examined the effects of PAAF obtained from a rat model of severe acute pancreatitis on the ability of peritoneal macrophages to produce tumor necrosis factor-alpha (TNF-alpha). In addition, we compared the responses of PAAF-treated and PAAF-untreated macrophages to lipopolysaccharide (LPS) by evaluating their TNF-alpha production and nuclear factor-kappaB (NFkappaB) activation. Incubation of peritoneal macrophages with the PAAF led to the rapid and prolonged activation of NF-kappaB and to TNF-alpha production. Pyrrolidine dithiocarbamate, a potent inhibitor of NF-kappaB activation, attenuated the macrophage TNF-alpha production by PAAF. Macrophages produced TNF-alpha in response to LPS, but the cytokine production was significantly reduced when macrophages were pretreated with PAAF. The suppression of TNF-alpha production by PAAF pretreatment accompanied the impairment of NF-kappaB activation in response to LPS. These results indicate that the PAAF of severe acute pancreatitis may play important roles in the pathologic course of this disease through its effects on macrophage function.

Development of a cell-free binding assay for rat ICAM-1/LFA-1 interactions using a novel anti-rat LFA-1 monoclonal antibody and comparison with a cell-based assay

The importance of the interaction between lymphocyte function-associated antigen-1 (LFA-1) and intercellular adhesion molecule-1 (ICAM-1) in the progression of inflammatory responses in vivo has been demonstrated mainly in rats. The present study was undertaken to develop binding assays suitable for measuring the rat ICAM-1/LFA-1 interaction in vitro. We first examined binding of rat T lymphoma FTL43 cells, which express LFA-1, to immobilized rat ICAM-1. Although FTL43 cells bound avidly to immobilized ICAM-1 and the binding was abolished with anti-LFA-1 monoclonal antibodies (mAbs), the binding was not completely inhibited by most anti-ICAM-1 mAbs. We next purified rat LFA-1 from FTL43 cells and constructed a cell-free binding assay. By using a newly developed anti-rat LFA-1 mAb RL14/9, which does not inhibit ICAM-1/LFA-1 interactions, binding of purified rat LFA-1 to immobilized ICAM-1 was successfully detected, whereas only a low signal to noise ratio was observed when binding of ICAM-1 to immobilized LFA-1 was examined. Moreover, we found that simultaneous addition of purified LFA-1 and biotinylated RL14/9 to ICAM-1-coated wells resulted in more sensitive detection of rat ICAM-1/LFA-1 binding. The binding was completely blocked with both anti-LFA-1 and anti-ICAM-1 mAbs and was much more sensitive to inhibition by the ICAM-1-IgG chimera, as compared with the cell-based assay. These results indicate that the cell-free binding assay provides a rapid and sensitive method for screening rat ICAM-1/LFA-1 antagonists, whose therapeutic effect on inflammatory diseases can further be evaluated in vivo.

Detection of anti-annexin IV and V antibodies in patients with antiphospholipid syndrome and systemic lupus erythematosus

OBJECTIVE

Annexins (Anx) are a family of structurally related proteins that bind to phospholipids in a calcium dependent manner. It has been reported that antibodies to Anx V, which acts as an antithrombotic protein, are associated with thrombosis in systemic lupus erythematosus (SLE) and/or antiphospholipid syndrome (APS). Homology between the primary structures of Anx IV and Anx V is the highest among members of the Anx family. We investigated whether anti-Anx IV autoantibodies can be detected in the sera of patients with SLE and/or APS.

METHODS

Seventy-four patients with SLE/APS were divided into 3 groups: Group A, patients with SLE but no clinical or serological features of APS; Group B, patients with SLE having only serological signs of APS; and Group C, patients with clinical symptoms and serological signs of APS. Anx IV and Anx V were prepared by recombinant technique. Anti-Anx IV, Anx V, cardiolipin (CL), and CL beta2-glycoprotein I were detected by ELISA.

RESULTS

Anti-Anx IV was found in 15.4% of Group A, 20.0% of Group B, and 21.7% of Group C. Anti-Anx V was found in 3.8% of Group A, 28.0% of Group B, and 30.4% of Group C. Significant correlations were noted between anti-Anx IV titer and anti-Anx V titer (p<0.001), and between anti-Anx IV titer and aCL titer (p<0.01).

CONCLUSION

Anti-Anx IV and V antibodies were characterized in the sera of patients with SLE/APS. Significantly higher frequency of arterial or venous thrombosis was found in patients with anti-Anx V.

Clinical, neuropathological, and molecular study in two families with spinocerebellar ataxia type 6 (SCA6)

To clarify the clinical, neuropathological, and molecular characteristics of spinocerebellar ataxia type 6 (SCA6), two unrelated Japanese families with SCA6 were studied. A clinical feature of the two families was late onset "pure" cerebellar ataxia. Pathologically, three SCA6 brains consistently showed Purkinje cell dominant cortical cerebellar degeneration. Morphometric analysis showed that loss of the cerebellar granule cells and inferior olivary neurons were very mild compared with the severity of Purkinje cell loss. There was no obvious ubiquitin immunoreactive nuclear inclusions. All affected patients had identical expanded alleles, and the expansion was also homogeneously distributed throughout the brain without mosaicism. The present study showed that SCA6 is characterised by Purkinje cell dominant cortical cerebellar degeneration, highly stable transmission of the CAG repeat expansion, and lack of ubiquitin immunoreactive nuclear inclusions.

Joint effects of HMG-CoA reductase inhibitors and eicosapentaenoic acids on serum lipid profile and plasma fatty acid concentrations in patients with hyperlipidemia

HMG-CoA reductase inhibitors reduce serum total cholesterol concentrations and the risk of coronary heart disease in patients with hypercholesterolemia. Recently, it has been reported that patients with combined hyperlipidemia are also at risk of coronary heart disease. However, HMG-CoA reductase inhibitor therapy alone does not sufficiently reduce serum triglyceride concentrations. Epidemiological and clinical evidence has shown that fish oil can lower plasma lipid levels, especially triglycerides. Consequently, we investigated the effects of the combination of HMG-CoA reductase inhibitors and eicosapentaenoic acid, a major component of fish oil, on hyperlipidemia. We administered 900-1,800 mg/day of the ethyl ester of eicosapentaenoic acid to patients with hyperlipidemia who had been treated with HMG-CoA reductase inhibitors for 30 +/- 6 months (means +/- SE). Serum total cholesterol and triglyceride concentrations were significantly decreased 3 months after the administration of eicosapentaenoic acid (from 5.63 +/- 0.23 mmol/l to 5.02 +/- 0.20 mmol/l, P < 0.05; from 2.07 +/- 0.41 mmol/l to 1.08 +/- 0.17 mmol/l, P < 0.01, respectively). Serum high-density lipoprotein-cholesterol concentrations were significantly increased after the treatment (from 1.23 +/- 0.12 mmol/l to 1.34 +/- 0.13 mmol/l, P < 0.05). Plasma eicosapentaenoic acid concentrations and the ratio to arachidonic acid in plasma were also significantly increased 3 months after the treatment (from 101.9 +/- 8.1 mg/l to 181.8 +/- 23.9 mg/l, P < 0.001; from 0.640 +/- 0.075 to 1.211 +/- 0.170, P < 0.001, respectively). These results suggested that the combination therapy of HMG-CoA reductase inhibitors and eicosapentaenoic acid was effective for patients with hyperlipidemia.

[Results of questionnaire to 56 medical institutions about clinical trials of cancer chemotherapy]

From the stand point of investigators doing clinical trials of anti-cancer drugs, a questionnaire to survey of the current status of clinical trials concerning on the reactions of medical institutions to the new GCP started in April 1997, sent to 75 institutions all over the Japan. 56 institutions (75%) gave answers to the questionnaire, in August 1998. As the results, apparent decrease of Phase II & III trials were noticed compared the numbers before March 1997. IRB with one or two outside members are well functioned in these institutions. But, training related doctors, nurses (especially CRC) are nowadays most important problems, which are strongly expected to Ministry of Health and Welfare and related medical societies, for instance Japan Society of Clinical Oncology.

Nectin/PRR: an immunoglobulin-like cell adhesion molecule recruited to cadherin-based adherens junctions through interaction with Afadin, a PDZ domain-containing protein

We have isolated a novel actin filament-binding protein, named afadin, localized at cadherin-based cell-cell adherens junctions (AJs) in various tissues and cell lines. Afadin has one PDZ domain, three proline-rich regions, and one actin filament-binding domain. We found here that afadin directly interacted with a family of the immunoglobulin superfamily, which was isolated originally as the poliovirus receptor-related protein (PRR) family consisting of PRR1 and -2, and has been identified recently to be the alphaherpes virus receptor. PRR has a COOH-terminal consensus motif to which the PDZ domain of afadin binds. PRR and afadin were colocalized at cadherin-based cell-cell AJs in various tissues and cell lines. In E-cadherin-expressing EL cells, PRR was recruited to cadherin-based cell-cell AJs through interaction with afadin. PRR showed Ca2+-independent cell-cell adhesion activity. These results indicate that PRR is a cell-cell adhesion molecule of the immunoglobulin superfamily which is recruited to cadherin-based cell-cell AJs through interaction with afadin. We rename PRR as nectin (taken from the Latin word "necto" meaning "to connect").

Clinicopathological study on liver dysfunction in measles

We analyzed the clinical course of eight patients with liver dysfunction in measles. All of the patients showed an elevation of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH), but no jaundice. These levels returned to normal about 3 weeks after the onset of the rash. A percutaneous liver biopsy was done in two cases. Histological examination showed slight necrosis of liver cells but no significant changes in portal area. On electron microscopy, virus particles were not detected. We detected measles virus RNA in the liver specimen by RT-PCR, which suggests that the measles virus affects liver cells directly in measles.

Lewy body-type degeneration in cardiac plexus in Parkinson's and incidental Lewy body diseases

Heart tissues of patients with PD or incidental Lewy body (LB) disease (ILBD) were examined by light and electron microscopy. LBs and alpha-synuclein-positive neurites were identified in the hearts from 9 of 11 patients with PD and from 7 of 7 patients with ILBD. LBs were present in both tyrosine hydroxylase-positive and -negative nerve processes, which are nerves of extrinsic sympathetic and intrinsic origin, respectively. These findings provide histologic evidence that the postganglionic sympathetic and intrinsic neurons in the heart are involved in the PD disease process.

A prospective study on the effects of early surgery on vasospasm after subarachnoid hemorrhage

BACKGROUND

To test the hypothesis that early surgery prevents vasospasm, a prospective analysis used strictly selected cases of anterior communicating artery aneurysms with symmetric distribution of subarachnoid hemorrhage.

METHODS

Seven patients underwent early surgery (9-29 hours after ictus) through a standard pterional approach. Subarachnoid blood clots surrounding the ipsilateral major cerebral arteries were meticulously irrigated and suctioned. Comparison was made between the hemispheres with surgical intervention and those without, in terms of incidence of delayed ischemic neurologic deficits and cerebral infarction on computed tomographic scans, degree of angiographic vasospasm, and cerebral blood flow (CBF).

RESULT

The degree of angiographic vasospasm, quantified by measuring the alterations in the ratio of the diameters of the intracranial arteries (C1, M1) to the extracranial internal carotid artery (C5), did not differ significantly between the surgical and nonsurgical sides. The mean CBF was also comparable between both sides in the chronic spasm phase (Day 6-9) as well as in the early postoperative period (Day 1-3). A significant reduction of CBF was observed during the early postoperative period in the basal frontal lobe of the surgical side. This CBF reduction seems to correspond to brain retraction.

CONCLUSIONS

The results suggest that the effect of clot removal may be offset by the negative aspect of early surgery, and early surgery per se seems to have little effect on the course of the chronic vasospasm.

Foldability of barnase mutants obtained by permutation of modules or secondary structure units

Modules, defined as stable, compact structure units in a globular protein, are good candidates for the construction of novel foldable proteins by permutation. Here we decomposed barnase into six modules (M1-M6) and constructed 23 barnase mutants containing permutations of the internal four (M2-M5) out of six modules. Globular proteins can also be subdivided into secondary structure units based on the extended structures that control the mutual relationships of the modules. We also decomposed barnase into six secondary structure units (S1-S6) and constructed 21 barnase mutants containing permutations of the internal four (S2-S5) out of six secondary structure units. Foldability of these two types of mutants was assessed by means of circular dichroism, fluorescence, and 1H-NMR measurements. A total of 15 of 23 module mutants and 15 of 21 secondary structure unit mutants formed definite secondary structures, such as alpha-helix and beta-sheet, at 20 microM owing to intermolecular interactions, but most of them converted to random coil structures at a lower concentration (1 microM). Of the 44 mutants, only two, M3245 and S2543, gave distinct near-UV CD spectra. S2543 especially showed definite signal dispersion in the amide and methyl regions of the 1H-NMR spectrum, though M3245 did not. Furthermore, urea-induced unfolding of S2543 monitored by far-UV CD and fluorescence measurements showed a distinct cooperative transition. These results strongly suggest that S2543 takes partially folded conformations in aqueous solution. Our results also suggest that building blocks such as secondary structure units capable of taking different stable conformations by adapting themselves to the surrounding environment, rather than building blocks such as modules having a specified stable conformation, are required for the formation of foldable proteins. Therefore, the use of secondary structure units for the construction of novel globular proteins is likely to be an effective approach.

Ponsin/SH3P12: an l-afadin- and vinculin-binding protein localized at cell-cell and cell-matrix adherens junctions

We recently isolated a novel actin filament (F-actin)-binding protein, afadin, that has two isoforms, l- and s-afadins. l-Afadin is ubiquitously expressed and specifically localized at zonula adherens (ZA) in epithelial cells and at cell-cell adherens junction (AJ) in nonepithelial cells, whereas s-afadin is abundantly expressed in neural tissue. l-Afadin has one PDZ domain, three proline-rich regions, and one F-actin-binding domain, whereas s-afadin lacks the third proline-rich region and the F-actin-binding domain. To understand the molecular mechanism of the specific localization of l-afadin at ZA in epithelial cells and at cell-cell AJ in nonepithelial cells, we attempted here to identify an l-afadin-binding protein(s) and isolated a protein, named ponsin. Ponsin had many splicing variants and the primary structures of two of them were determined. Both the two variants had three Src homology 3 (SH3) domains and turned out to be splicing variants of SH3P12. The third proline-rich region of l-afadin bound to the region of ponsin containing the second and third SH3 domains. Ponsin was ubiquitously expressed and localized at ZA in epithelial cells, at cell-cell AJ in nonepithelial cells, and at cell-matrix AJ in both types of cells. Ponsin furthermore directly bound vinculin, an F-actin-binding protein localized at ZA in epithelial cells, at cell-cell AJ in nonepithelial cells, and at cell-matrix AJ in both types of cells. Vinculin has one proline-rich region where two proline-rich sequences are located. The proline-rich region bound to the region of ponsin containing the first and second SH3 domains. l-Afadin and vinculin bound to ponsin in a competitive manner and these three proteins hardly formed a ternary complex. These results indicate that ponsin is an l-afadin- and vinculin-binding protein localized at ZA in epithelial cells, at cell-cell AJ in nonepithelial cells, and at cell-matrix AJ in both types of cells.

Loss of 123I-MIBG uptake by the heart in Parkinson's disease: assessment of cardiac sympathetic denervation and diagnostic value

Myocardial imaging with 123I-metaiodobenzylguanidine (MIBG) was performed on 35 patients with Parkinson's disease and 24 control subjects to evaluate cardiac sympathetic function in patients with Parkinson's disease, verify this phenomenon and examine whether myocardial MIBG uptake and clearance are correlated with the clinical severity of Parkinson's disease.

METHODS

We studied 35 patients with Parkinson's disease and 24 control subjects with other central nervous system diseases. The latter group consisted of 12 subjects with other neurodegenerative disorders (4 with spinocerebellar degeneration, 2 with amyotrophic lateral sclerosis, 3 with progressive supranuclear palsy and 3 with corticobasal degeneration and 12 patients with cerebral infarction (CI), 6 with vascular parkinsonism and 6 without it. Early and delayed images of the anterior view were obtained 15 min and 4 h after injection of 123I-MIBG, respectively. MIBG uptake was quantified by calculating a heart-to-mediastinum count (H/M) ratio.

RESULTS

The H/M ratio was markedly reduced in the patients with Parkinson's disease (II to V on the Hoehn and Yahr scale) compared with the control subjects. None of the subjects with neurodegenerative diseases showed a marked decrease in myocardial MIBG uptake nor did any subject with CI.

CONCLUSION

Our findings indicate that, in Parkinson's disease, a reduction in myocardial MIBG uptake is a very common, specific phenomenon that can be used to detect cardiac autonomic dysfunction to diagnose Parkinson's disease, particularly in patients without typical signs and symptoms.

Different behavior of l-afadin and neurabin-II during the formation and destruction of cell-cell adherens junction

We have recently isolated two novel actin filament-binding proteins, l-afadin and neurabin-II and shown that they are localized at cell-cell adherens junction (AJ) in epithelial cells. We found here that l-afadin, neurabin-II, ZO-1, and E-cadherin showed similar and different behavior during the formation and destruction of cell-cell AJ in MDCK cells. In MDCK cells, the accumulation of both l-afadin and E-cadherin, but not that of ZO-1, changed in parallel depending on Rac small G protein activity. Dissociation of MDCK cells by culturing the cells at 2 microM Ca2+ caused rapid endocytosis of E-cadherin, but not that of l-afadin or ZO-1. Addition of phorbol 12-myristate 13-acetate to these dissociated cells formed a tight junction-like structure where ZO-1 and l-afadin, but not neurabin-II or E-cadherin, accumulated. We furthermore found that, in non-epithelial EL cells, which expressed E-cadherin and attached to each other, l-afadin, neurabin-II, ZO-1 and E-cadherin were all localized at AJ. In cadherin-deficient L cells, I-afadin was mainly localized at cell-cell contact sites, but ZO-1 was mainly localized at the tip area of cell processes. Neurabin-II did not accumulate at the plasma membrane area. Neither l-afadin nor neurabin-II significantly interacted with alpha-, beta-catenin, E-cadherin, ZO-1 or occludin.

Intraparenchymal and intrasylvian haematomas secondary to ruptured middle cerebral artery aneurysms: prognostic factors and therapeutic considerations

The aim of this study was to investigate prognostic factors and the most appropriate treatment for patients with ruptured middle cerebral artery (MCA) aneurysms in relation to haematoma distribution. Ninety-two patients with ruptured MCA aneurysms, who underwent surgery during the last 11 years from 1986 to 1996, were assigned to one of the three groups according to the haematoma distribution. Group A comprised 17 patients who had an intraparenchymal haematoma (IPH) larger than 30 mm (maximum diameter) with or without subarachnoid haemorrhage (SAH), group B comprised 24 patients having a dense intra-Sylvian fissure haematoma (ISH) larger than 30 mm (maximum diameter) and group C consisted of 52 patients having only diffuse SAH without a localized dense haematoma. The clinical course and factors affecting the outcome of the patients in each group were investigated. Patients in groups A and B had a more severe clinical grade on admission than those in group C. As a result, patients in these two groups had a poorer outcome. In group C, independent life was achieved for 98% of the patients. In group A, the clinical grade on admission and the diameter of the haematoma were significantly correlated with outcome. Initial brain damage due to IPHs seemed to be the main cause of disability, while only 7% developed delayed ischaemic neurological deficits (DIND). In group B, 54% of patients suffered from subsequent brain oedema and DIND occurred in 50%. These factors were related to a poor outcome. The MCA aneurysms tend to have localized dense haematomas, as well as diffuse SAH; the former seems to affect more on the course and outcome of the patients. Accurate assessment of the bleeding patterns in patients with ruptured MCA aneurysms will be useful in helping us predict the clinical course and the most appropriate treatment for these individuals.

[Bilateral diabetic infarction of the thigh adductor muscles in a diabetic female patient-- A case report and review of the literature]

A 30-year-old female complained of lancinating pain in the bilateral thighs for 10 days. The patient had a 22-year history of insulin-dependent diabetes mellitus. Physical examination revealed swelling of the bilateral lower extremities. There was exquisite tenderness on palpation over the medial thighs, with marked increase in pain on hip and knee flexion. Muscle strength of quadriceps, hamstrings, and hip adductor was decreased due to muscle pain. Pedal pulses were palpable bilaterally. Roentogenograms of the left femur revealed calcification of the left femoral arterial wall. Venogram revealed no obstruction with normal drainage. Complete blood cell count showed left shift of the neutrophils, markedly accelerated erythrocyte sedimentation rate, prolonged prothorombin time of 9 sec (normal 11.7 sec), C-reactive protein of 7.3 mg/dl and serum creatine kinase level of 175 IU/L. FBS was 225 mg/dl and Hb A 1 c was 16.4%. An MR imaging of the thighs revealed high signal intensities in the bilateral adductor muscles on T 2-weighted images. The symptoms resolved spontaneously over a three week period. From the course of the illness and MR imaging, the patient was diagnosed having diabetic muscle infarction (DMI), a rare complication of diabetes mellitus. To our knowledge, this is the first reported case of DMI in Japan. Diabetic microangiopathy and hypercoagulability are thought to be responsible for inducing DMI. Because the diagnosis can be made from the characteristic clinical and the typical MR imaging findings, muscle biopsy is not always necessary to obtain the diagnosis of DMI.

Inhibition of nuclear factor-kappaB activation improves the survival of rats with taurocholate pancreatitis

BACKGROUND

Death in the early stages of severe acute pancreatitis is frequently the result of multiple organ dysfunction, but its mechanism is not clear.

AIMS

To investigate the state of nuclear factor-kappaB (NF-kappaB) in macrophages of rats with lethal pancreatitis, and to assess the effectiveness of pyrrolidine dithiocarbamate, an inhibitor of NF-kappaB, on the pathology and mortality.

METHODS

Taurocholate pancreatitis was produced in rats, and the severity of the disease, the mortality, and activation of NF-kappaB in peritoneal and alveolar macrophages were compared in rats receiving pyrrolidine dithiocarbamate (PDTC) treatment and those that were not.

RESULTS

Taurocholate pancreatitis produced massive necrosis, haemorrhage, and severe leucocyte infiltration in the pancreas as well as alveolar septal thickening in the lung. NF-kappaB was activated in peritoneal and alveolar macrophages six hours after pancreatitis induction. Pretreatment with PDTC dose-dependently attenuated the NF-kappaB activation and improved the survival of the rats, although it did not affect the early increase in serum amylase and histological findings.

CONCLUSIONS

Early blockage of NF-kappaB activation may be effective in reducing fatal outcome in severe acute pancreatitis.

Post-traumatic pituitary apoplexy--two case reports

A 60-year-old female and a 66-year-old male presented with post-traumatic pituitary apoplexy associated with clinically asymptomatic pituitary macroadenoma manifesting as severe visual disturbance that had not developed immediately after the head injury. Skull radiography showed a unilateral linear occipital fracture. Magnetic resonance imaging revealed pituitary tumor with dumbbell-shaped suprasellar extension and fresh intratumoral hemorrhage. Transsphenoidal surgery was performed in the first patient, and the visual disturbance subsided. Decompressive craniectomy was performed in the second patient to treat brain contusion and part of the tumor was removed to decompress the optic nerves. The mechanism of post-traumatic pituitary apoplexy may occur as follows. The intrasellar part of the tumor is fixed by the bony structure forming the sella, and the suprasellar part is free to move, so a rotational force acting on the occipital region on one side will create a shearing strain between the intra- and suprasellar part of the tumor, resulting in pituitary apoplexy. Recovery of visual function, no matter how severely impaired, can be expected if an emergency operation is performed to decompress the optic nerves. Transsphenoidal surgery is the most advantageous procedure, as even partial removal of the tumor may be adequate to decompress the optic nerves in the acute stage. Staged transsphenoidal surgery is indicated to achieve total removal later.

Brownian Dynamics Simulations of Ferromagnetic Colloidal Dispersions in a Simple Shear Flow

We have carried out Brownian dynamics simulations to investigate the behavior of clusters of ferromagnetic particles in a colloidal dispersion subjected to a simple shear flow. The results have been compared with those of Stokesian dynamics and Monte Carlo simulations. The main results obtained here are summarized as follows. The Brownian dynamics method can capture thick chain-like clusters formed along a magnetic field, in agreement with the Stokesian dynamics and Monte Carlo methods. However, Brownian motions of the particles give a subtle influence on the internal structure of thick chain-like clusters even in the case in which the magnetostatic interactions dominate the particle Brownian motions. The Stokesian dynamics method leads to a physically unreasonable cluster formation in the case in which the particle Brownian motions play an important role compared with that of the magnetic particle-particle interactions. We conclude that the Brownian dynamics method gives rise to physically realistic cluster formations in simulation of colloidal dispersions and therefore the method is to be preferred to the Stokesian dynamics method. Copyright 1999 Academic Press.

Nexilin: a novel actin filament-binding protein localized at cell-matrix adherens junction

We isolated two novel actin filament (F-actin)-binding proteins from rat brain and rat 3Y1 fibroblast. They were splicing variants, and we named brain big one b-nexilin and fibroblast small one s-nexilin. b-Nexilin purified from rat brain was a protein of 656 amino acids (aa) with a calculated molecular weight of 78,392, whereas s-nexilin, encoded by the cDNA isolated from rat 3Y1 cells by the reverse transcriptase-PCR method, was a protein of 606 aa with a calculated molecular weight of 71,942. b-Nexilin had two F-actin- binding domains (ABDs) at the NH2-terminal and middle regions, whereas s-nexilin had one ABD at the middle region because 64 aa residues were deleted and 14 aa residues were inserted in the first NH2-terminal ABD of b-nexilin, and thereby the first ABD lost its activity. b- and s-nexilins bound along the sides of F-actin, but only b-nexilin showed F-actin cross-linking activity. b-Nexilin was mainly expressed in brain and testis, whereas s-nexilin was mainly expressed in testis, spleen, and fibroblasts, such as rat 3Y1 and mouse Swiss 3T3 cells, but neither b- nor s-nexilin was detected in liver, kidney, or cultured epithelial cells. An immunofluorescence microscopic study revealed that s-nexilin was colocalized with vinculin, talin, and paxillin at cell- matrix adherens junction (AJ) and focal contacts, but not at cell-cell AJ, in 3Y1 cells. Overexpressed b- and s-nexilins were localized at focal contacts but not at cell-cell AJ. These results indicate that nexilin is a novel F-actin-binding protein localized at cell-matrix AJ.

Incorporation of water-insoluble anticancer drug into polymeric micelles and control of their particle size

A water-insoluble anticancer drug, KRN 5500 (KRN), was incorporated into polymeric micelles forming from poly(ethylene glycol-poly(amino acid) block copolymers by physical entrapment utilizing hydrophobic interactions between this drug and the poly(amino acid) chain block of the block copolymers. Three block copolymers were examined for this incorporation; poly(ethylene glycol)-poly(beta-benzyl l-aspartate) (PEG-PBLA) and its two derivatives obtained by partial hydrolysis at the beta-benzyl l-aspartate (BLA) units (PEG-P(Asp, BLA)) and by partial cetyl ester substitution at the BLA units (PEG-P(C16, BLA)), respectively. Among these block copolymers, considerable effects of the cetyl esterification were seen on KRN yield and particle size. Considerable differences in the KRN incorporation yield and particle size were also observed between DMF and DMS used as solvent to dissolve KRN and the block copolymers. Sonication was turned out to be an effective method to obtain a polymer micelles fraction in high efficiency, and sonication was considered to work for separating intermicellar associates into dispersed micelles. A KRN incorporation procedure by dialysis using PEG-P(C16, BLA) and DMSO (as solvent) followed by sonication brought about polymeric micelles of 71 nm in weight-average diameter. This shows successful incorporation of a water-insoluble drug into polymeric micelles by optimizing block copolymer structure and incorporation conditions.

Purification, characterization and cDNA cloning of soluble carbonic anhydrase from Chlorella sorokiniana grown under ordinary air

Soluble carbonic anhydrase (CA, EC 4.2.1.1) inducible by low levels of CO2 was purified from the unicellular green alga Chlorella sorokiniana grown at alkaline pH. The purified CA had a specific activity of 2,300 units (mg protein)-1. The molecular mass of the CA was found to be 100 kDa by non-dissociating (native)-polyacrylamide gel electrophoresis and 50 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The 50-kDa subunit was recognized by concanavalin A. These results suggest that the protein has a dimeric form with two 50-kDa subunits that are glycosylated in an asparagine-linked manner. The native CA was revealed by isoelectric focusing to be a very acidic protein with an isoelectric point of 4.2. About 60% of the CA activity was inhibited by 0.5 M NaCl. The enzyme was inactivated over 95% by preincubation with 50 mM dithiothreitol but not with 1 mM dithiothreitol. After partial amino acid sequence analysis, a cDNA clone of the CA was isolated and characterized. The cloned cDNA fragment encoded a 348-amino-acid polypeptide (36,709 Da) including an NH2-terminal hydrophobic signal peptide composed of 35 amino acids (3,725 Da). Conserved regions of sequences found in animal CAs, in the periplasmic (pCA) and the intracellular CAs of Chlamydomonas, and in the plasma-membrane-bound CA of Dunaliella (Dca) were also found in this Chlorella CA. The signal sequence was significantly homologous to the pCA and the Dca. The internal signal sequence between the large and the small subunits reported for pCA was not found in this Chlorella CA. The soluble CA of this alga was an alpha-type CA with salt-sensitive, periplasm-locating and acidic properties and very different from pCA and Dca with their salt-sensitive/neutral and salt-resistant/acidic properties, respectively.