A chemoenzymatic synthesis of UDP-(2-deoxy-2-fluoro)-galactose and evaluation of its interaction with galactosyltransferase

Uridine 5'-diphospho-(2-deoxy-2-fluoro)galactose (UDP-2FGal), prepared and characterized for the first time by a chemoenzymatic method, was found to be a competitive inhibitor of beta-1,4-galactosyltransferase with a Ki value of 149 microM. This study supports that the glycosyltransferase reaction mechanism proceeds through a glycosidic cleavage transition state with sp2 character developed at the anomeric center.

A case of early myoclonic encephalopathy with the congenital nephrotic syndrome

We describe a male infant with early myoclonic encephalopathy (EME) associated with the congenital nephrotic syndrome, microcephaly, multiple minor anomalies, and cerebellar hypoplasia. He had erratic and massive myoclonus, and partial seizures from the neonatal period. Electroencephalography showed the so-called suppression-burst pattern. He died of disseminated intravascular coagulation caused by the congenital nephrotic syndrome at the age of two months. Our patients is the first reported case with EME associated with the congenital nephrotic syndrome.

Role of platelets in myocardial ischemia-reperfusion injury in dogs

We investigated the involvement of circulating platelets in myocardial ischemia-reperfusion injury in canine autoperfused heart-lung preparations using filters to deplete platelets and/or leukocytes. The left anterior descending (LAD) coronary artery was occluded for 40 min, followed by 40 min reperfusion, in 3 groups: a leukocyte-platelet-depleted (LPD) group, in which both leukocytes and platelets were depleted; a leukocyte-depleted (LD) group, in which leukocytes alone were depleted; and a control group. There were no differences in hemodynamics or arrhythmias among groups before or during coronary occlusion. After reperfusion, the maximum rate of change in left ventricular pressure during systole and diastole was significantly higher in the LPD group than in the control and LD groups. The LPD group also showed gradual recovery of regional myocardial function and a decrease in the frequency of premature ventricular contractions. The LD group showed a slight improvement in cardiac function and arrhythmias compared with the control group. Although there was no significant difference in the pulmonary arterial plasma level of thromboxane B2 at any stage among groups, the control group showed an increase after reperfusion. These results suggest that platelets are important in reperfusion injury and that the depletion of both leukocytes and platelets effectively protects against reperfusion injury.

Changes in levels of mRNAs for cell wall-related enzymes in growing cotton fiber cells

mRNAs for cell wall-related enzymes in developing cotton fiber cells were measured by reverse transcription-PCR analysis. Both endo-1,4-beta-glucanase and expansin mRNA levels were high during cell elongation but decreased when cell elongation ceased, and xyloglucan decreased. The endo-1,3-beta-glucanase mRNA level was very low in the elongating cells but increased gradually at the onset of secondary wall synthesis, accompanying the massive deposition of cellulose. Endoxyloglucan transferase and sucrose synthase mRNA levels were constant during all stages of growth.

Persistence of cyclopiazonic acid-induced endothelium-dependent vasodilatation in spontaneously hypertensive and streptozotocin-induced diabetic rats

We recently reported that cyclopiazonic acid (CPA) releases a novel endothelium-derived relaxing factor that is not prostacyclin, nitric oxide or endothelium-derived hyperpolarizing factor in rat mesenteric arterial bed. The acetylcholine-induced vasodilatation of the isolated mesenteric bed in spontaneously hypertensive rats (SHR) was not different from that in Wistar Kyoto rats (WKY), but it was significantly smaller in streptozotocin (STZ)-induced diabetic rats than in age-matched controls. The CPA-induced vasodilatation was not affected in SHR or in STZ-induced diabetic rats. These results suggest that the CPA-induced endothelium-dependent vasodilatation is resistant to the effects of diabetes.

Helical CT evaluation of arterial invasion in pancreatic tumors: comparison with angiography

BACKGROUND

Although helical computed tomography (HCT) has been widely employed for the evaluation of pancreatic tumors, its capability in the diagnosis of peripancreatic arterial invasion has not been established.

METHODS

HCT with a sequential cine-display was carried out in 34 patients with solid pancreatic tumors and 28 control subjects without angiographic abnormality. The HCT scans were compared with angiograms.

RESULTS

All major arteries (celiac, superior mesenteric, splenic, gastroduodenal) and superoanterior pancreaticoduodenal arteries were well demonstrated by HCT in control subjects. However, posterior pancreaticoduodenal arcades and other smaller arteries were poorly identified. Although 19 major arterial invasions were equally diagnosed by HCT and angiography in patients with pancreatic tumors, only 4 of 11 minor arterial invasions were correctly diagnosed by HCT.

CONCLUSIONS

Although HCT has some limitations in the evaluation of minor peripancreatic arteries, it can provide enough information for making a decision about conducting pancreatic surgery.

Calcium spirulan as an inducer of tissue-type plasminogen activator in human fetal lung fibroblasts

Calcium spirulan (Ca-SP), a novel sulfated polysaccharide isolated from the blue-green alga Spirulina platensis, has been found to have antiviral and heparin cofactor II-dependent antithrombin activities. We have obtained evidence that Ca-SP is a potent inducer of tissue-type plasminogen activator (t-PA) production. The addition of Ca-SP to a culture of IMR-90 human fetal lung fibroblasts increased t-PA concentrations in the conditioned medium, in a dose- and time-dependent manner, but in the cell lysate, t-PA concentrations were unchanged, suggesting that t-PA induced by Ca-SP is easily secreted into the conditioned medium. The amount of newly synthesized t-PA in IMR-90 cells, as measured by labeling with [35S]methionine and subsequent immunoprecipitation of t-PA from conditioned medium, was significantly increased by Ca-SP-stimulation. However, Ca-SP did not increase the t-PA mRNA levels. As previously reported, thrombin stimulated t-PA gene transcription in IMR-90 cells, and the simultaneous treatment with Ca-SP and thrombin caused further enhancement of t-PA production, in a synergistic manner. It would thus appear that Ca-SP increases t-PA production through post-transcriptional processes. IMR-90 cells also produce plasminogen activator inhibitor type-1 (PAI-1), but Ca-SP showed little effect on the PAI-1 production. H-SP, which was obtained by removing the calcium from Ca-SP, had no effect on the t-PA production. Na-SP, which was prepared by replacement of the calcium with sodium, stimulated the t-PA production similarly to Ca-SP. Thus, Ca-SP specifically induces t-PA production, and the molecular conformation of Ca-SP maintained by Ca or Na may be essential for the stimulation of t-PA synthesis.

Changes in intracellular Ca2+ concentration produced by the alteration of intracellular pH in rat parotid acinar cells

The effects of intracellular pH (pH(i)) on intracellular Ca2+ concentration ([Ca2+]i) vary in different cells, and mechanisms underlying these effects are still not clear. In the experiments reported here, the effects of changes in pH(i) produced by ammonium chloride and butyric acid were studied in enzymatically dispersed acinar cells of rat parotid glands. The changes in pH(i) and [Ca2+]i were estimated using the fluorescent dyes biscarboxyethyl-5,6-carboxyfluorescein (BCECF) and fura-2, respectively. pH(i) was altered using NH4Cl, butyric acid, or propionic acid while keeping the external pH constant at 7.4. NH4Cl (20 mM) applied for 4-5 min increased pH(i) from 7.18 to 7.79 (a decrease of proton concentration, [H+]i, from 66 to 16 nM) and produced a transient [Ca2+]i increase followed by a small sustained decrease. On the other hand, butyric acid (20 mM) decreased pH(i) from 7.16 to 6.81 (an increase of [H+]i from 69 to 155 nM) and produced a small sustained increase in [Ca2+]i. Washing out the butyric acid 4 min after application induced the recovery of pH(i) from 6.93 to 7.43 (a decrease of [H+]i from 118 to 37 nM) and a further transient increase in [Ca2+]i. The removal of external Ca2+ had little effect on changes in pH(i) produced by NH4Cl or butyric acid, but markedly reduced both the sustained and transient components of [Ca2+]i response. Cyclopiazonic acid (0.3 microM), an inhibitor of Ca2+ pump in intracellular stores, abolished the transient [Ca2+]i increase produced by the application of NH4Cl or withdrawal of butyric acid. These results suggest that a decrease in [H+]i, not the absolute level of [H+]i may release Ca2+ from intracellular stores.

Nitric oxide production by superficial and deep articular chondrocytes

OBJECTIVE

Chondrocytes have been shown to produce large amounts of nitric oxide (NO) when appropriately stimulated with proinflammatory cytokines or bacterial lipopolysaccharide (LPS). In view of recent observations underscoring profound phenotypic differences between superficial and deep articular chondrocytes, these studies investigated NO production, inducible NO synthase (iNOS) activity, and messenger RNA (mRNA) expression of superficial and deep cartilage explants and cells.

METHODS

Superficial and deep bovine and human articular cartilage explants and isolated bovine chondrocytes were cultured in the presence of stimulating cytokines or LPS. NO was measured by the Griess reagent. Inducible NOS activity was quantitated by conversion of L-14 C-arginine to L-14C-citrulline. Inducible NOS mRNA expression was quantitated by reverse transcription-polymerase chain reaction (RT-PCR) and in situ hybridization.

RESULTS

Superficial bovine cartilage explants stimulated with interleukin-1 alpha, LPS, or tumor necrosis factor alpha for 24 and 48 hours produced significantly more NO than did deep explants with all stimulants and at both times. Similar results were obtained with stimulated isolated superficial and deep cells. NO synthase activity, measured by the conversion of L-14C-arginine to L-14C-citrulline, paralleled NO production. Comparable results were obtained using explants from a normal human donor. Semiquantitation of iNOS mRNA by RT-PCR showed significantly larger amounts of PCR products in superficial cells and superficial explants. These results were confirmed by in situ hybridization of explants and isolated cells.

CONCLUSION

Increased NO production at the cartilage surface-synovial fluid interface may play an important role in the modulation of cartilage damage in inflammatory arthritis.

Life-threatening dysphagia following prolonged neuroleptic therapy

We report the cases of two patients with complaints of dysphagia following long-term neuroleptic therapy. Esophageal contrast radiography revealed that one patient suffered disruption of the normal swallowing activity of the pharyngoesophagus due to tardive dyskinesia. Her dysphagia disappeared following changes in her neuroleptic medications and the administration of clonazepam. The other patient demonstrated severe rabbit syndrome involving the glossopharynx. This 3-Hz rhythmic movement disorder resolved following injection of an anticholinergic agent. Thereafter, the addition of oral trihexyphenidyl to her medication regimen improved her dysphagia. It should be emphasized that the differential diagnosis of neuroleptic-associated dysphagia subtypes is important because therapeutic strategies differ depending on the subtype of this life-threatening illness.

Effects of work-related stress reduction on depressive symptoms among Japanese blue-collar workers

OBJECTIVES

The effects of a stress reduction program on Japanese blue-collar workers were investigated using a controlled trial design.

METHODS

Two blue-collar worksites that showed higher depression scores (Zung self-rating depression score) were selected for the intervention group, after a survey of a large electric company in 1985. Three blue-collar worksites were selected as a reference group whose workers were matched with the workers of the interventive worksites by mean age, worksite size and mean depression scores. A 1-year stress reduction program was conducted in the intervention group from 1986 to 1987 by worksite supervisors. Effects of the stress reduction program were assessed by comparing the initial depression scores, length of sick leave, and systolic and diastolic blood pressures with those after the follow-up.

RESULTS

The depression scores decreased during the follow-up in the intervention group, while the scores were almost the same in the reference group. An analysis of covariance with repeated measurements indicated a statistically significant intervention (group x time interaction) effect after control for gender and age (P = 0.035). Sick leave in the past year decreased in 1988 only in the intervention group; generalized logit analysis with repeated measurements indicated a statistically significant intervention effect after control for gender and age (P = 0.034). No statistically significant intervention effects were observed on systolic and diastolic blood pressures or selected work stressors.

CONCLUSIONS

A stress reduction program directed towards worksite supervisors can be used to reduce depressive symptoms and sick leave among Japanese blue-collar workers.

Möbius-like syndrome associated with a 1;2 chromosome translocation

We report here a rare case of Möbius-like syndrome associated with a 1;2 chromosome reciprocal translocation (46,XY,t(1;2)(p22.3;q21.1). The patient had facial diplegia, ptosis, anteverted nostrils, malformed and lowset ears, and slight developmental delay. Since a microdeletion could be present at the breakpoint in a reciprocal translocation, it is possible that the gene responsible for Möbius syndrome is located in this region of chromosome 1.

Stimulation of cell proliferation and inhibition of gap junctional intercellular communication by linoleic acid

The effect of linoleic acid (LA) on gap-junction permeability, connexin 43 mRNA level, protein level, and phosphorylation, and the numbers of gap-junctional membrane plaques were studied in the rat liver epithelial cell line WB-F344 to determine whether changes in these parameters correlated with the enhanced cell growth and the inhibition of gap-junction function. When cultured in a medium with low serum (1%), these cells exhibited a slower growth rate than in the high serum medium (7%). Addition of linoleic acid (0.01-3 mg/ml) to the low serum medium increased the growth rate and inhibited gap junctional intercellular communication (GJIC) in a dose-dependent manner. In a comparison of short-term and long-term treatments with LA, GJIC in short-term treated (1 h) WB cells was inhibited at 3 mg/ml LA but readily recovered by washing and removing LA from cells, whereas GJIC in long-term treated (6 days) WB cells did not recover by washing and removing LA from WB cells. Western blot analysis of connexin 43 showed that a short-term incubation with linoleic acid increased the relative amount of unphosphorylated connexin 43 protein, but a long-term incubation with linoleic acid decreased the amount of unphosphorylated connexin 43 protein and increased the relative amount of hyperphosphorylated connexin 43 protein. Connexin 43 and p53 mRNA levels decreased in a time- and dose-dependent manner in linoleic acid-treated cells. These results suggest that growth stimulation and gap junctional intercellular communication inhibition of rat liver epithelial cells by linoleic acid may be mediated in part through modulation of p53 expression and function.

Expression of inducible nitric oxide synthase in T lymphocytes and macrophages of cholesterol-fed rabbits

While endothelial nitric oxide synthase has been reported to be expressed in the endothelial cells of normal and atherosclerotic vessels, there are few reports about inducible nitric oxide synthase (iNOS). We investigated the expression of iNOS and its relation to inflammatory cells in atheroma. New Zealand White rabbits were fed 1 of 4 diets: (i) normal diet for 9 weeks; (ii) normal plus 1% cholesterol diet (atherogenic diet) for 9 weeks; (iii) atherogenic diet for 9 weeks, then normal diet for 9 weeks; (iv) atherogenic diet for 9 weeks, then the normal diet for 36 weeks. The aortas were examined by immunohistochemical staining for anti-iNOS antibody, as well as antibodies for macrophages, T lymphocytes, and muscle actin. No iNOS was detected in normal aortas, intimal thickenings, or fatty streaks. Although iNOS was detected in necrotic cores of advanced plaque, it was not seen in smooth muscle-derived cells or endothelial cells but was found in some macrophage-derived cells and in T lymphocytes. In regressive atherosclerotic aortas, iNOS was detected only in necrotic cores, not in macrophage-derived cells but in T lymphocytes. These findings suggest that T lymphocytes and some macrophages induce iNOS through cytokine production in atheroma. This is the first report of iNOS expression in atheromatous plaque.

Synthesis and biological activity of a 1 alpha,25-dihydroxyvitamin D2 analog bearing an amide group in the side-chain

Synthesis of a 1 alpha,25-dihydroxyvitamin D2 analog (3), in which the double bond in the side-chain is replaced by an amide group, is described. Condensation of a carboxylic acid (8) with an amine (6) gave an amide (9), which in turn led to 3 via several steps. The analog (3) could not bind to the chick cytosol vitamin D receptor, which indicated the importance of the hydrophobic interaction of the C(22)-C(23) double bond in 1 alpha,25-dihydroxyvitamin D2 (2) with the vitamin D receptor.

Controllability of temporomandibular joint loading by coordinative activities of masticatory muscles: a two-dimensional static analysis

Masticatory and bite forces, when applied to the teeth, generate tremendous compressive energy in the temporomandibular joint (TMJ). Excessive 'TMJ loading', if left untreated, deteriorates articular functions. Normally, it is controlled, to a certain extent, by stomatognathic means. In an attempt to clarify this control mechanism, we analyzed the relationship between TMJ loading and the activities of the masticatory muscles, by employing a static two-dimensional jaw model. This comprises two rigid bodies, the upper and lower jaws, including three dominant muscles, i.e. the masseter, the anterior portion of the temporalis and the lateral pterygoid. Static equilibrium analyses determined that TMJ loading can be minimized, under controlled bite conditions, by pointing the loading vector in a direction solely indicated by individual morphological factors, such as the position and orientation of the masseter and the temporalis. This theoretically optimum direction of TMJ loading was also anatomically acceptable, because the load is applied exactly to those portions of the articular disk and mandibular head that can most easily sustain it. Interestingly, this factor was absolutely independent of both the activities of the lateral pterygoid and the direction of bite force. Consequently. TMI loading can be minimized, by coordinating the activities of the masseter and the anterior portion of the temporalis.

Positional reproducibility of the patient's head normalized by a robotized chair-based automatic head-positioning system, Racs-N

With a view to normalization of the head orientation without the use of a fixation jig for the measurement of jaw movement employing an X-ray television, we have been developing an automatic head-positioning system, Racs-N, consisting of a head-position sensor and a robotized chair. The head position is monitored in 6 degrees of freedom (d.o.f.) by using a position-sensitive detector (PSD) camera-based photostereometry. If they are incorrect, the robotized chair rectifies them automatically by adjusting the position and orientation of the head support in 5 d.o.f. (except the vertical position). The rectified position, however, has a certain margin of error, due to the mobility of the head relative to the head support. To improve this, we employed an iterative correction in that the positioning is repeated until the determined position converges. In experiments employing several subjects, this particular correction was verified to converge by more than six iterations and to be effective for the reduction of head-position errors.

Ultrastructural changes during myocardial hypertrophy and its regression: long-term effects of nifedipine in adult spontaneously hypertensive rats

Nifedipine (20 mg/kg/day) was given to 15-week-old spontaneously hypertensive rats for 20 weeks (SHR-N, n = 8). Comparison was done with sex-matched 15-week-old SHR (SHR-15, n = 7), untreated 35-week-old SHR (SHR-C, n = 10), 15-week-old normotensive Wistar-Kyoto rats (WKY-15, n = 15), and 35-week-old WKY (WKY-15, n = 5). Light and electron microscopic data on the subepicardial, middle and subendocardial layers and papillary muscles of the left ventricle were compared among the five rat groups. In SHR-N, blood pressure was significantly reduced by nifedipine, but was higher than in WKY-35 (199 +/- 11 mmHg vs 121 +/- 13 mmHg). The left ventricular weight/body weight ratio was much lower in SHR-N than in SHR-C, and was even below the baseline value in SHR-15. In addition, cardiac myocyte diameter was much smaller in each myocardial layer of SHR-N than in SHR-C, and was similar to the findings in SHR-15, but still larger than in WKY-35. The interstitial area ratio was markedly reduced in SHR-N and did not differ from that in SHR-15 or even WKY-15, while capillary density was significantly greater than in SHR-C and comparable to that in WKY-35. In SHR-C, large fibrotic foci were common, and many hypertrophic cardiac myocytes showed various degenerative changes including those of mitochondria and widening of the intermyofibrillar spaces. These changes were rarely seen in SHR-N. The intracellular volume ratio of myofibrils did not differ between SHR-N and WKY-35, but was significantly decreased in SHR-C, whereas that of mitochondria did not differ between SHR-N and SHR-C or WKY-35. These findings indicate that despite only a moderate suppression of hypertension, long-term nifedipine treatment caused regression of left ventricular hypertrophy, with cardiocyte hypertrophy, interstitial fibrosis, degenerative changes, and subcellular remodeling being reversed to the baseline levels in SHR-15. In addition, the capillary density was increased to that seen in WKY-35.

Automatic head positioning system using PSD-equipped camera-based photostereometry and a 5-degree-of-freedom robotized chair: calibration and accuracy verification

In measurements of jaw movements employing an X-ray television, the orientation of the patient's head must be normalized relative to the measuring device. To avoid interferring with natural jaw movements caused by using a positioning jig, we have developed an automatic head positioning system consisting of a head position sensor and a robotized chair. The position and orientation of the head is monitored by detecting the three-dimensional positions of four non-coplanar LED markers mounted on the head, by means of a set of two photoelectronic cameras. If they are incorrect, the head is moved into the required position, using a 5-degree-of-freedom robotized chair. To accomplish this accurately, the positional relations of system components must be determined precisely. This paper proposes a least-square technique of calibrating the relationship between the position sensor and the chair. Consequently, accurate positioning is achieved. Accuracy verification studies revealed that overall positioning errors lay within 2.42 mm and 1.28 degrees with respect to the position and orientation, respectively, if the markers are secured to the head support of the chair.

[Indication for percutaneous transluminal coronary angioplasty based on quality of life of patients with angina pectoris]

The changes in quality of life (QOL) before and after percutaneous transluminal coronary angioplasty (PTCA) were investigated to establish criteria for determining whether patients with angina pectoris should undergo PTCA. The QOL was surveyed twice by self-completed questionnaire for QOL by Iida and Kohashi (QUIK) before and about 4 months after PTCA in 84 patients (mean age 62.8 +/- 10.1 years) with angina pectoris. High QUIK score reflects a poor QOL, of which the internal consistency was 0.86, demonstrating high reliability. The subjects were classified into three groups according to the changes of total QUIK score before and after PTCA (I: QOL improved 31.0%, II: QOL unchanged 48.8%, III: QOL worsened 20.2%). Age, gender, total QUIK score prior to PTCA, presence of anginal pain, complications extent and degree of coronary artery stenosis, and left ventricular ejection fraction were compared between the three groups. The total QUIK score prior to PTCA in the improved QOL group was higher than that in the worsened QOL group (11.6 vs 5.1, p < 0.01). Most patients showing a poor QOL prior to PTCA demonstrated an improvement in their QOL after PTCA. The number of patients with anginal pain prior to PTCA was high in the improved QOL group (35.8%, p < 0.05). Percutaneous transluminal coronary angioplasty might not aggravate QOL (12.1%, p = 0.1) in patients with single-vessel disease. In patients with multivessel disease, PTCA might not improve (35.3%) but also might aggravate QOL (25.5%). Multivariate analysis showed that PTCA improved QOL in male or sixty-ager patients and in patients with a total QUIK score of 10 or more prior to PTCA (p < 0.01). The total QUIK score, presence of anginal pain and extent of coronary artery stenosis prior to PTCA, gender and age are factors predicting QOL after PTCA. The adaptation of PTCA for those patients should be prudently and inclusively taken into consideration to extend their QOL.

Isolated collagen IV retains the potential to form an 18-nm sided polygonal meshwork of the lamina densa

Polygonal meshworks were revealed in the aggregates reconstituted from isolated collagen IV as well as in the lamina densa of mouse pancreas by the quick-freezing and deep-etching technique. Collagen IV solution with acetic acid from the bovine lens capsules and that isolated from the pepsin-solubilized fraction of human placenta reconstituted polygonal meshworks, which were dimensionally similar to the meshwork seen in the lamina densa of mouse pancreas. The average lengths between branching points in the lamina densa, and the meshworks of collagen IV derived from the bovine lens capsules and from the human placenta were 20.1 +/- 7.7 nm (mode = 18 nm), 21.6 +/- 11.3 nm (mode = 14 nm), and 21.6 +/- 9.0 nm (mode = 18 nm), respectively. These observations suggest that collagen IV can, in the absence of other macromolecules including laminins, comprise a skeletal meshwork similar in dimensions to that of the lamina densa.

Clinical features of familial diffuse Lewy body disease

We present 5 patients from two families with familial autosomal dominant diffuse Lewy body disease. All 5 patients initially showed parkinsonian symptoms that responded well to levodopa therapy; however, dementia followed and later progressed. In 3 patients, the disease was manifested before age 40 years, exhibiting wearing-off phenomenon and choreic limb dyskinesia. One patient was examined neuropathologically, and brain stem lesions compatible with Parkinson's disease were revealed, and Lewy bodies and senile plaques were found in the cerebral cortex. Familial cases of diffuse Lewy body disease may provide some explanation of the pathogenesis of this disease.