Contribution of the carbohydrate moiety to conformational stability of the carboxypeptidase Y high pressure study

The process of pressure-induced denaturation of carboxypeptidase Y and the role of the carbohydrate moiety in its response to pressure and low temperature were investigated by measuring in situ the catalytic activity and, the intrinsic and 8-anilino-1-naphthalene sulfonic acid binding fluorescences. Pressure-induced denaturation of carboxypeptidase Y is a process involving at least three transitions. Low pressures (below 150 MPa) induced slight conformational changes characterized by a slight decrease in the center of the spectral mass of intrinsic fluorescence, whereas no changes in 8-anilino-1-naphthalene sulfonic acid binding fluorescence were observed and 80% of the catalytic activity remained. Higher pressure (150-500 MPa) induced further conformational changes, characterized by a large decrease in the center of the spectral mass of intrinsic fluorescence, a large increase in the 8-anilino-1-naphthalene sulfonic acid binding fluorescence and the loss of all catalytic activity. Thus, this intermediate exhibited characteristics of molten globule-like state. A further increase, in pressure (above 550 MPa) induced transition from this first molten globule-like state to a second molten globule-like state. This two-stage denaturation process can be explained by assuming the existence of two independent structural domains in the carboxypeptidase molecule. A similar three-transition process was found for unglycosylated carboxypeptidase Y, but, the first two transitions clearly occurred at lower pressures than those for glycosylated carboxypeptidase Y. These findings indicate that the carbohydrate moiety protects carboxypeptidase Y against pressure-induced denaturation. The origin of the protective effects is discussed based on the known crystallographic structure of CPY.

Motor unit discharge pattern in soleus muscles associated with rapid body sway

Motor unit discharge (MUD) patterns of the soleus muscles associated with rapid forward body sway were studied in relation to displacement of the center of foot pressure (CFP) and to angular changes in the position of the ankle joint. Subjects were instructed to shift the CFP from a relaxed bending posture (N) to a leaning posture half of maximally forward (1/2F) by swaying their bodies, pivoting at the ankles as rapidly and accurately as possible following an auditory signal. Ten motor units recorded from 5 subjects were studied. During body sway accompanied by elongation of the soleus muscle, a stereotyped serial motor unit discharge pattern was observed: cessation of unit discharge (acceleration phase), and then resumption of unit discharge (deceleration and stop phase). The rate of MUD during the deceleration and stop phase was higher than that when subjects held their bodies during holding his body at N or 1/2F. A strong positive correlation was observed between the timing of the resumption of MUD and both the CFP changes and the angular changes in the position of the ankle joint. These results strongly suggest that peripheral inputs are important for control of both the timing of the resumption and the frequency of MUD in the performance of a rapid body sway.

Role of carbohydrate moiety in carboxypeptidase Y: structural study of mutant enzyme lacking carbohydrate moiety

To study the roles of the carbohydrate moiety in the function of carboxypeptidase Y, asparagine residues at 13, 87, 168, and 368, the four-consensus N-linked glycosylation sites, were altered to alanine with site-directed mutagenesis. The mutant enzyme of 51 kDa completely lost the carbohydrate moiety which was present in the 61-kDa wild-type enzyme. Structural studies of the mutant enzyme showed that it maintained the native-like structure; hydrolytic activity, and substrate specificity of the mutant enzyme analogous to those of the wild-type enzyme. Susceptibility of the mutant enzyme toward proteolysis and pressure denaturation was reduced by 10-20%. It is concluded that the carbohydrate moiety functions to maintain the structural integrity of the enzyme under stressed.

Reactive oxygen intermediates stimulate interleukin-6 production in human bronchial epithelial cells

Reactive oxygen intermediates (ROIs) play an important role in the initiation and progression of lung diseases. In this study, we investigated whether ROIs were involved in the induction of interleukin (IL)-6 in human bronchial epithelial cells. We exposed normal human bronchial epithelial cells as well as a human bronchial epithelial cell line, HS-24, to ROIs. We measured the amount of IL-6 in the culture supernatants using ELISA and the IL-6 mRNA levels using RT-PCR. Superoxide anions (O-2), but not hydrogen peroxide (H2O2), increased IL-6 production. To examine whether it is a cell type-specific mechanism of airway epithelial cells, the experiments were also performed in human lung fibroblasts, WI-38-40. In WI-38-40 cells, neither O-2 nor H2O2 increased IL-6 production. In contrast, tumor necrosis factor (TNF)-alpha (200 U/ml) induced IL-6 at the protein and mRNA levels in both airway epithelial cells and lung fibroblasts. This cytokine-induced IL-6 production was significantly suppressed by several antioxidants, including dimethyl sulfoxide (DMSO), in airway epithelial cells. In WI-38-40 cells, DMSO was not able to suppress IL-6 production induced by TNF-alpha. Pretreatment with DMSO recovered the TNF-alpha-induced depletion of intracellular reduced glutathione in HS-24 cells. These findings indicate that oxidant stress specifically induces IL-6 production in human bronchial epithelial cells and that in these cells ROIs may be involved in IL-6 production after stimulation with cytokines such as TNF-alpha. Presumably, ROIs participate in the local immune response in lung diseases via IL-6 release from bronchial epithelial cells.

A large maxillofacial prosthesis for total mandibular defect: a case report

We successfully fabricated a large maxillofacial prosthesis for replacement of a total mandibular defect resulting from surgical failure to reconstruct the mandible. Although a number of reports have described procedures for fabricating midfacial prostheses, there is little information on prostheses to compensate for total loss of the mandible. A 54-year-old woman was referred to the Dentistry and Oral Surgery Division of the National Cancer Center Hospital with total loss of the mandible and the surrounding facial soft tissue. The facial prosthesis we used to treat this patient is unique in that it is adequately retained without the use of extraoral implants and conventional adhesives. This prosthesis is retained by the bilateral auricles and the remaining upper front teeth. We present details of the design of this large silicone maxillofacial prosthesis, with which we successfully rehabilitated the patient.

A sequence-ready contig map of the top arm of Arabidopsis thaliana chromosome 3

A fine physical map of the top arm of Arabidopsis thaliana chromosome 3 has been constructed by ordering P1, TAC and BAC clones using the sequences of a variety of DNA markers and end-sequences of clones. The marker sequences used in this study were derived from 58 DNA markers, 93 YAC end-sequences, and 807 end-sequences of P1, TAC and BAC clones. The entire top arm of chromosome 3, except for the centromeric and telomeric regions, was covered by a single contig 13.3 Mb long. This fine physical map will facilitate gene isolation by map-based cloning experiments as well as genome sequencing of the top arm of chromosome 3. The map and end-sequence information are available on the web site KAOS (Kazusa Arabidopsis data Opening Site) at [http://www.kazusa.or.jp/arabi/].

Ultrastructural changes of erythrocyte membrane skeletons in chorea-acanthocytosis and McLeod syndrome revealed by the quick-freezing and deep-etching method

The shapes of acanthocytic erythrocytes have been thought to be related to changes of the organization of the membrane components. In this study, acanthocytes from a patient with chorea-acanthocytosis and a patient with McLeod syndrome were examined. These acanthocytes had a greater tendency to form spikes than normal erythrocytes in an incubation culture system, indicating their weakness against membrane tension. The membrane skeletons of erythrocytes from both patients were examined by our erythrocyte-splitting method followed by the quick-freezing and deep-etching method. The ultrastructural organization of the membrane skeletons was heterogeneous even in individual erythrocytes, indicating regional changes in the compactness of their meshworks. In the process of erythrocyte splitting, some erythrocyte membranes became reversed and protruded into the cytoplasmic side. In these regions, there were fewer filamentous structures. The focal membrane skeletal changes, which are probably one of the factors that induce the phenotype of an acanthocytic erythrocyte, were demonstrated for the first time by this method.

Optically active antifungal azoles. VIII. Synthesis and antifungal activity of 1-[(1R,2R)-2-(2,4-difluoro- and 2-fluorophenyl)-2-hydroxy-1-methyl-3-(1H-1,2,4-triazol-1-yl)propyl]- 3-(4-substituted phenyl)-2(1H,3H)-imidazolones and 2-imidazolidinones

New optically active antifungal azoles, 1-[(1R,2R)-2-(2,4-difluoro- and 2-fluorophenyl)-2-hydroxy-1-methyl-3-(1H-1,2,4-triazol-1-yl)propyl ]-3-(4- substituted phenyl)-2(1H,3H)-imidazolones (1,2) and 2-imidazolidinones (3,4), were prepared in a stereocontrolled manner from (1S)-1-[(2R)-2-(2,4- difluoro- and 2-fluorophenyl)-2-oxiranyl]ethanols (15, 16). Compounds 1-4 showed potent antifungal activity against Candida albicans in vitro and in vivo, as well as a broad antifungal spectrum for various fungi in vitro. Furthermore, the imidazolidinones, 3b--e and 4d, e, were found to exert extremely strong growth-inhibitory activity against Aspergillus fumigatus.

Characterization of a 1200-kb genomic segment of chromosome 3p22-p21.3

We previously determined the nucleotide sequence and characterized the 685-kb proximal half of CEPH YAC936c1, which corresponds to a portion of human chromosome 3p21.3. In the study reported here, we characterized the remaining 515-kb of this YAC clone corresponding to the telomeric half of its human insert. The newly sequenced region contained a total of ten genes including six reported previously: phospholipase C delta 1 (PLCD1), human activin receptor type IIB (hActR-IIB), organic cation transporter-like 1 (OCTL1), organic cation transporter-like 2 (OCTL2), oxidative stress response 1 (OSR1), and human xylulokinase-like protein (XYLB). The remaining four genes present in the telomeric region included two known genes, MyD88 and ACAA, and two novel genes. One (designated ENGL) of the novel sequences was found to encode an amino-acid sequence homologous to the family of DNA/RNA endonucleases, especially endonuclease G. The other gene F56 revealed no significant homology to any known genes. These results disclosed complete physical and transcriptional maps of the 1200-kb region of 3p present in YAC 936c1.

Cardiovascular function before and after iron therapy by echocardiography in patients with iron deficiency anemia

BACKGROUND

The aim of the study was to estimate the left ventricular contractility using the ratio of left ventricular end-systolic wall stress to left ventricular end-systolic volume index in patients with iron deficiency anemia, for which there are no previous reports.

METHODS

Cardiovascular functions were evaluated using echocardiography and pulsed Doppler echocardiography in 30 children aged 3-14 years (hemoglobin 4.9-8.5 g/dL), before, during and after iron therapy. We also studied 38 healthy children as a control group.

RESULTS

The left ventricular preload was significantly higher and the left ventricular afterload was lower in the patients with anemia before iron therapy. The ratio of left ventricular end-systolic wall stress to left ventricular volume, an index of systolic function that is independent of preload and afterload, was significantly lower in the patients with anemia before iron therapy (before iron therapy 2.13 +/- 0.44, after therapy 3.52 +/- 0.76, healthy controls 3.42 +/- 0.70). Left ventricular early diastolic filling was significantly higher in the patients with anemia before iron therapy. The cardiac index was also significantly higher before therapy because of the increases in preload, heart rate and early diastolic filling, as well as the decrease of afterload. There were no significant differences in the indices of cardiovascular function between anemic patients after iron therapy compared with control subjects.

CONCLUSIONS

The ratio of left ventricular end-systolic wall stress to the left ventricular volume index and the cardiac index suggested that a hemoglobin concentration < or = 6 g/dL was associated with left ventricular dysfunction and circulatory congestion.

Glucose transporter 2 concentrations in hyper- and hypothyroid rat livers

The deterioration of glucose metabolism frequently observed in hyperthyroidism may be due in part to increased gluconeogenesis in the liver and glucose efflux through hepatocyte plasma membranes. Glucose transporter 2 (GLUT 2), a facilitative glucose transporter localized to the liver and pancreas, may play a role in this distorted glucose metabolism. We examined changes in the levels of GLUT 2 in livers from rats with l-thyroxine-induced hyperthyroidism or methimazole-induced hypothyroidism by using Western blotting to detect GLUT 2. An oral glucose tolerance test revealed an oxyhyperglycemic curve (impaired glucose tolerance) in hyperthyroid rats (n=7) and a flattened curve in hypothyroid rats (n=7). GLUT 2 levels in hepatocyte plasma membranes were significantly increased in hyperthyroid rats and were not decreased in hypothyroid rats compared with euthyroid rats. The same results were obtained with a densitometric assay. These findings suggest that changes in the liver GLUT 2 concentration may contribute to abnormal glucose metabolism in thyroid disorders.

Free adipofascial flap for scalp reconstruction: case report

The authors describe a case in which a large defect of the scalp was present after tumor excision. It was covered with a free adipofascial flap and a split-thickness skin graft, with satisfactory results. Numerous similar cases of scalp defects reconstructed with other free flaps have been described. But since donor-site morbidity is minimized with free adipofascial flaps, they should be used more often for reconstruction of scalp defects.

The central role of CD4(+) T cells in the antitumor immune response

The induction of optimal systemic antitumor immunity involves the priming of both CD4(+) and CD8(+) T cells specific for tumor-associated antigens. The role of CD4(+) T helper cells (Th) in this response has been largely attributed to providing regulatory signals required for the priming of major histocompatibility complex class I restricted CD8(+) cytolytic T lymphocytes, which are thought to serve as the dominant effector cell mediating tumor killing. However, analysis of the effector phase of tumor rejection induced by vaccination with irradiated tumor cells transduced to secrete granulocyte/macrophage colony-stimulating factor indicates a far broader role for CD4(+) T cells in orchestrating the host response to tumor. This form of immunization leads to the simultaneous induction of Th1 and Th2 responses, both of which are required for maximal systemic antitumor immunity. Cytokines produced by these CD4(+) T cells activate eosinophils as well as macrophages that produce both superoxide and nitric oxide. Both of these cell types then collaborate within the site of tumor challenge to cause its destruction.

Bradykinin stimulates interleukin-8 production by human lung fibroblasts

Bradykinin (BK) is a potent inflammatory mediator that is generated from kininogens by the actions of plasma and tissue kallikreins. Lung fibroblasts have the potential to participate in the inflammatory responses by releasing proinflammatory cytokines in response to a variety of stimuli. We postulated that human lung fibroblasts might produce interleukin-8 (IL-8) in response to BK stimulation. The present study showed that BK stimulated human lung fibroblasts to produce IL-8 in a dose- and time-dependent manner. Furthermore, Northern blot analysis showed that BK increased IL-8 mRNA expression. The stimulatory effect of BK on IL-8 production was detected at the concentration of 10 nm, and the maximal stimulation was achieved with 100 to 1000 nm. Phorbol 12-myristate 13-acetate pretreatment diminished the ability of BK to stimulate IL-8 production. In addition, GF109203X, a selective protein kinase C inhibitor, blocked BK-induced IL-8 production. These observations suggest that the stimulatory effect of BK on IL-8 production by lung fibroblasts is, at least partially, mediated through protein kinase C. These data suggest that BK may be involved in the inflammatory reaction leading to interstitial lung disorders through stimulating IL-8 production by lung fibroblasts.

[Surgical treatment of differentiated thyroid cancer with tracheal invasion]

Thirty patients with tracheal invasion of differentiated thyroid cancer underwent partial resection of the tracheal wall between 1978 and 1996 at National Cancer Center Hospital. In most cases, the defect in the tracheal wall was reconstructed secondarily using a local flap. This method was easy in comparison with end-to-end anastomosis of the trachea following circumferential resection of the wall. Partial resection of the tracheal wall proved to be a effective treatment for thyroid cancer invasion of the tracheal, because of low incidence of local recurrence. When the defect of the tracheal wall was too large to be reconstructed using a local flap, hydroxylapatite was employed and good results were obtained.

Effects of thyroid hormone on the sorbitol pathway in streptozotocin-induced diabetic rats

Sorbitol accumulation plays an important role in diabetic complications involving the kidney, nerves, retina, lens and cardiac muscle. To investigate the influence of thyroid hormone on the sorbitol pathway, we studied the effects of thyroid hormone on polyol metabolism in normal and diabetic rats. Rats were divided into three groups: controls, streptozotocin (STZ)-induced diabetic euthyroid rats (DM) and STZ-induced diabetic hyperthyroid (thyroxine-injected) rats (DM+HT). The sorbitol (Sor) concentrations in the kidney, liver and sciatic nerve (2.53+/-0.74, 0.97+/-0.16 and 24.0+/-5.1 nmol/mg protein, respectively) of the DM rats were significantly higher than those (1.48+/-0.31, 0.58+/-0.13 and 3. 1+/-0.6 nmol/mg protein) of the control rats. The Sor concentrations in the kidney and sciatic nerve of the DM+HT rats (1.26+/-0.29 and 9. 40+/-1.2 nmol/mg protein) were significantly lower than those in the DM rats. These values were reduced in the liver, unchanged in the kidney, and increased in the sciatic nerve from the hyperthyroid rats without diabetes. Thyroid hormone reduced the aldose reductase (AR) activities in the kidney, liver and sciatic nerve of the DM rats, and similarly reduced AR in the kidney and liver, but not in the sciatic nerve, of the non-diabetic rats. The sorbitol dehydrogenase (SDH) activities were decreased by thyroid hormone in the kidney and liver but not the sciatic nerve of DM rats. In the non-diabetic rats, this enzyme activity was decreased in liver, but not in kidney or sciatic nerve. A positive correlation between the Sor concentration and AR activity was observed in the kidney and liver but not in the sciatic nerve from control, DM and DM+HT rats. A negative correlation was observed between the Sor concentration and SDH activities in the same organs. These data suggest that thyroid hormone affects the sorbitol pathway, but the detailed mechanism whereby this hormone reduces the sorbitol content (especially in diabetic rats) remains to be clarified.

Leukoencephalopathy induced by chemotherapy with tegafur, a 5-fluorouracil derivative

We report an autopsy case of a 64 year-old Japanese man diagnosed as having leukoencephalopathy caused by tegafur, a 5-fluorouracil derivative, and review seven previous cases, mostly reported in Japan. In the present case, tegafur had been orally administered for the shortest period of 3 weeks in pre- and postoperative cancer chemotherapy. He died 2 years later after having made a slight recovery from a prolonged akinetic mute state. Unlike similar cases previously reported, the degeneration of the white matter was most prominent in the temporal lobes. Histologically, the severely involved white matter showed nearly complete myelin and axonal loss with a proliferation of hypertrophic astrocytes. In the less severely involved areas, such as in the frontal white matter where myelin was relatively well preserved, numerous activated microglial cells and a small number of T lymphocytes were identified immunohistochemically. The cerebral cortex, cerebellum and brain stem were well preserved, which is consistent with the previous reports. Literature review revealed that the histopathological features of the lesions reported in human cases are quite different from those reported in animal experiments.

Neuroleptic malignant syndrome during haloperidol treatment in a cancer patient. A case report

A case of neuroleptic malignant syndrome (NMS) in a 64-year-old man with cancer of the soft palate is reported. During haloperidol treatment for delirium, the patient showed consciousness disturbance with extrapyramidal signs. With discontinuation of haloperidol and replacement by dantrolene and bromocriptine, the patient recovered completely. Although major tranquilizers are widely used in clinical oncology to manage symptoms, NMS has been rarely reported in cancer patients, presumably because of lack of awareness. Early recognition of NMS and prompt treatment may improve the potentially fatal outcome.

Accumulation of acid-fast lipochrome bodies in glial cells of the midbrain nigral lesion in Parkinson's disease

To confirm or refute the proposed link between nocardiae and Parkinson's disease (PD), we investigated the presence of acid-fast spherical structures similar to filterable nocardiae at the midbrain nigral lesions of three patients with PD. Many clusters of acid-fast lipochrome bodies were dense around blood vessels in the two patients with Hoehn and Yahr stage II and III PD. These clusters were present in the vicinity of melanin-pigmented neurons in the three PD patients studied. Examination of adjacent hematoxylin-and-eosin-stained sections indicated that they consisted of yellow-green granules, bodies, and aggregates in ballooned glial cells. On the other hand, no clusters of acid-fast lipochrome bodies were observed at the compacta region of three control patients. Our results suggest that the immunological and genetic relationship between the acid-fast lipochrome bodies and filterable nocardiae should be investigated.

Mexiletine in the treatment of spasmodic torticollis

We studied the clinical efficacy of mexiletine, a derivative oral form of lidocaine, for treatment of spasmodic torticollis. One of the nine subjects of this study was previously reported. Before starting oral mexiletine, normal saline was first injected intravenously as placebo control; lidocaine infusion then followed and clinical evaluation was provided by dystonia rating scale scores, videotape recordings, and surface electromyographic recording. In all patients, lidocaine injection resulted in a decrease of dystonic muscle contractions within 5 minutes and the effect lasted approximately 1 hour. With gradual increase of mexiletine dose, similar clinical improvement was obtained with oral doses ranging from 450-1200 mg/day for more than 6 months. Side effects in six of nine patients included upper gastrointestinal symptoms, dizziness, ataxia, and dysarthria. These were tolerable or medically manageable; only one patient required a small reduction in mexiletine dose. Strong positive correlation was found between serum and cerebrospinal fluid (CSF) mexiletine concentrations with a CSF/serum ratio of 0.6 (r = 0.96, p = 0.0005) suggesting its effective penetrance into the central nervous system. We suggest that oral mexiletine therapy may be a safe and effective treatment for spasmodic torticollis.

Microorganism inactivation using high-pressure generation in sealed vessels under sub-zero temperature

In order to test the possibility of utilizing high pressure in bioscience and biotechnology, a simple method for high-pressure generation and its use for microbial inactivation have been studied. When a pressure vessel was filled with water, sealed tightly and cooled to sub-zero temperatures, high pressure was generated in the vessel. The pressure generation was 60 MPa at -5 degrees C, 103 MPa at -10 degrees C, and 140 MPa at -15 degrees C, -20 degrees C, and -22 degrees C. The high pressure generated inactivated microorganisms effectively: yeasts (Saccharomyces cerevisiae and Zygosaccharomyces rouxii), bacteria (Lactobacillus brevis and Eschericia coli), and fungi (Aspergillus niger and Aspergillus oryzae) were completely inactivated when stored in sealed vessels -20 degrees C for 24 h. However, Staphylococcus aureus was only partly inactivated under the same conditions. This method opens up a new application of high pressure for storing, transporting, and sterilizing of foods and biological materials.

Power spectral analysis of auditory brainstem responses and MRI findings in patients with spinocerebellar degeneration

Power spectrum analysis of auditory brainstem responses (ABR) and magnetic resonance imaging (MRI) findings were obtained from 14 patients, 9 with olivopontocerebellar atrophy (OPCA; Dejerine-Thomas type) and 5 with Holmes-type cerebello-olivary degeneration, and compared to data from normal controls. The power spectrum was divided into three components according to frequency: up to 400 Hz (slow component); from 400 to 800 Hz (middle component); and 800 to 3,000 Hz (fast component). In patients with OPCA, the slow component appeared significantly less often than in both groups, normal controls (p < 0.0005) and patients with Holmes-type degeneration (p < 0.005), and the middle component appeared significantly more often than in both groups (p < 0.0005). There was a significant positive correlation between the proportion of the slow component and midbrain diameter (p = 0.04) and a significant negative correlation between the proportion of the fast component and midbrain diameter (p = 0.02). We conclude that the power spectrum differs between OPCA and Holmes-type degeneration, and that the proportion of each component of the power spectrum is related to midbrain volume.

Quantitative differentiation of both free 3'-OH and 5'-OH DNA ends between heat-induced apoptosis and necrosis

Cell death is roughly categorized as either apoptosis or necrosis. For better understanding of the differences in DNA cleavage between them, we performed quantitative analysis of both the 3'-OH and the 5'-OH ends of DNA strand breaks via in situ nick-end labeling (ISEL) combined with transmission electron microscopy (TEM) of both heat-induced apoptosis and necrosis in mouse B-cells derived from a lymphoma cell line. To detect the 5'-OH ends, the 3'-P ends located on the opposite side holding the 5'-OH ends were dephosphorylated into 3'-OH ends with alkaline phosphatase. As assessed by statistical analysis of both the 3'-OH and the 5'-OH ends, their labeling densities were significantly higher in both the apoptotic and the necrotic cells in the early stage than in control cells. The labeling densities increased during the apoptotic and necrotic processes, except for a decrease in the density of the 3'-OH ends in necrotic cells in the late stages. Therefore, DNA degradation in both necrosis and apoptosis provides early evidence for these processes, and both apoptosis and necrosis may share at least the first steps of DNA degradation pathways.