Participation of an arginyl residue of insulin chain B in the inhibition of hemagglutination by Porphyromonas gingivalis

Insulin chain B, containing each one arginyl and lysyl residue in its peptide chain, inhibited hemagglutination by Porphyromonas gingivalis. To determine the further inhibitory profile, chain B was digested into 4 fragments by protease, which was contained in the preparation of hemagglutinin from P. gingivalis. Identification of each fragment by the amino acid analysis revealed that the chain was cleaved at the carboxyl site of arginyl and/or lysyl residues, but one fragment contained citrulline instead of arginine at its carboxyl terminal. This citrulline might have originated from arginine by an arginine deiminase-like enzyme of P. gingivalis. Only one fragment that contained the arginyl residue exhibited inhibitory activity on hemagglutination, but it was considerably weakened compared with that of the intact chain B. The difference in the inhibitory activity seemed to depend on the position of an arginyl residue in the peptide; this was also confirmed using several derivatives of bradykinin. The present result suggests that the internal arginyl residue in a peptide chain may be critical for the inhibition of the hemagglutination by P. gingivalis.

A structural study of the asparagine-linked oligosaccharide moiety of duck ovomucoid

Asparagine-linked oligosaccharides of duck ovomucoid were released quantitatively from the protein by digestion with glycoamidase A (from almond), the reducing ends of the oligosaccharide chains thus obtained were aminated with a fluorescent reagent, 2-aminopyridine, and the mixture of pyridylamino derivatives of the oligosaccharides was separated using two different types of high performance liquid chromatography (HPLC) on a reversed phase column and an amide adsorption column. More than sixteen different oligosaccharides were separated and the structures were characterized by a combination of the 2-dimensional sugar mapping technique using HPLC, exoglycosidase digestion, and proton nuclear magnetic resonance measurements (1- and 2-dimensional). Furthermore, the HPLC profile of duck ovomucoid oligosaccharides was compared with previously reported profiles obtained from quail and chicken ovomucoids.

Episodic multiregional cortical coherence at multiple frequencies during visual task performance

The way in which the brain integrates fragmentary neural events at multiple locations to produce unified perceptual experience and behaviour is called the binding problem. Binding has been proposed to involve correlated activity at different cortical sites during perceptuomotor behaviour, particularly by synchronization of narrow-band oscillations in the gamma-frequency range (30-80 Hz). In the rabbit olfactory system, inhalation induces increased gamma-correlation between sites in olfactory bulb and cortex. In the cat visual system, coherent visual stimuli increase gamma-correlation between sites in both the same and different visual cortical areas. In monkeys, some groups have found that gamma-oscillations transiently synchronize within striate cortex, superior temporal sulcus and somatosensorimotor cortex. Others have reported that visual stimuli produce increased broad-band power, but not gamma-oscillations, in several visual cortical areas. But the absence of narrow-band oscillations in itself does not disprove interregional synchronization, which may be a broad-band phenomenon. We now describe episodes of increased broad-band coherence among local field potentials from sensory, motor and higher-order cortical sites of macaque monkeys performing a visual discrimination task. Widely distributed sites become coherent without involving other intervening sites. Spatially selective multiregional cortical binding, in the form of broad-band synchronization, may thus play a role in primate perceptuomotor behaviour.

Follow up study on children with dyslipidaemia detected by mass screening at 18 months of age: effect of 12 months dietary treatment

The present study was done to evaluate the effect of short-term dietary therapy on 148 dyslipidaemic children (24 familial hypercholesterolaemia, 105 non-familial hypercholesterolaemia and 19 hypertriglyceridaemia), detected by mass screening in children at 18 months of age. In the model diet used for treatment, 15% of the total calories were obtained from protein, 27% from fat and 57% from carbohydrate. Cholesterol intake was set at < 200 mg/day and the ratio of polyunsaturated to saturated fatty acid (P/S ratio) was 1.2. When compared to the composition of the diet ingested by the dyslipidaemic children, only the P/S ratio changed from 0.7 to 1.2. During 12 months treatment, levels of total cholesterol, low density lipoproteins cholesterol and apoB decreased by 10%-15% in children with familial and non-familial hypercholesterolaemia. There was no significant change in the levels of high density lipoproteins. In 19 children with hypertriglyceridaemia, the intake of carbohydrate was limited to 55% of the total calories consumed and after 12 months of treatment, triglyceride levels reverted to normal. Throughout the study period, approximately 70% of the children on this dietary therapy were seen in our clinics every 3-6 months and physical development was within normal ranges. These results, taken together, indicate that dietary therapy can be effective for correcting dyslipidaemia, even in young children.

A change in soybean agglutinin binding patterns of bovine milk fat globule membrane glycoproteins during early lactation

Milk fat globule membrane (MFGM) glycoproteins were prepared from bovine milk at different stages of early lactation. Western blot analyses using several lectins revealed that reactivity of MFGM glycoproteins, especially 47K and 80K bands, to soybean agglutinin (SBA) remarkably increased during the lactation, while no change was observed for Ricinus communis agglutinin-I (RCA-I) binding. Sialidase treatment of MFGM glycoproteins revealed that the number of SBA-positive bands and the amount of SBA-positive oligosaccharides in these bands are increased during the lactation. Since SBA binds N-acetylgalactosamine terminated oligosaccharides, the results indicated that N-acetylgalactosaminylation of bovine MFGM glycoproteins is stimulated during the lactation.

[The utility of three-phase bone scintigraphy in the assessment of fractured carpal scaphoid]

Thirty-seven joints in 36 patients with a fractured carpal scaphoid were evaluated by three-phase bone scintigraphy. They were classified into two groups according to their progress. Some were in good clinical condition and some in a non-union condition. Increased blood flow in the radial arteries and ample perfusion on and around the scaphoid bones on blood flow images suggested a good clinical course. The activity and the effectiveness of remodeling correlated well with the degree of scaphoid uptake on blood pool images taken more than seven days after the injury. Scaphoid uptake was more localized or there was almost none on blood pool images in cases with nearly complete recovery while it was amply visualized on static images. Blood pool images were indispensable for analyzing lesions and evaluating the clinical course. Two typical findings of scaphoid fractures were found on both blood pool and static images. One was diffusely increased scaphoid uptake seen in cases with a good clinical course, and the other was decreased uptake at proximal fragments seen in cases with non-union. It is concluded that three-phase bone scintigraphy provides useful information for evaluating the process of scaphoid fractures which cannot be obtained by means of conventional bone scintigraphy.

LDL inhibits the mediation of cholesterol efflux from macrophage foam cells by apoA-I-containing lipoproteins. A putative mechanism for foam cell formation

Although the accumulation of cholesterol in macrophages appears to be an initial step in atherogenesis, low-density lipoprotein (LDL), a major risk factor for atherosclerosis, does not promote cholesterol accumulation in macrophages in its native form. On the other hand, apolipoprotein (apo) A-I-containing lipoprotein removes cholesterol from cholesterol-loaded macrophages (foam cells) and prevents cholesterol from accumulating in the cells. We examined the effect of LDL on cholesterol removal by two species of apoA-I-containing lipoproteins, one containing only apoA-I (LpA-I) and the other containing apoA-I and apoA-II (LpA-I/A-II). When foam cells were incubated with LpA-I or LpA-I/A-II, cellular cholesterol mass was reduced. In contrast, when LDL was added, the cholesterol-reducing capacities of these lipoproteins were dose-dependently inhibited by LDL. In the presence of LDL, LpA-I and LpA-I/A-II removed free cholesterol preferentially from LDL rather than from the plasma membrane of foam cells. In addition, a fair amount of cellular cholesterol was directly moved to LDL rather than to LpA-I or LpA-I/A-II. The cellular cholesterol that moved to LDL was completely compensated for by the cholesterol influx from LDL to foam cells. Thus, net cholesterol efflux (a combination of influx and efflux) from foam cells was inhibited by LDL. These results, taken together, indicate that LDL may accelerate foam cell formation by inhibiting cholesterol removal from the cells and that elevated levels of plasma LDL may become a risk factor for atherosclerosis by inhibiting the function of LpA-I and LpA-I/A-II at the cellular level.

Establishment and characterization of a novel human monocytic leukemia cell line (KP-1) expressing scavenger receptor

A new monocytic leukemia cell line (KP-1) was established from a 2-y-old Japanese girl with acute monocytic leukemia. The KP-1 cells were maintained in suspension culture with a doubling time of 96 h. The cells were positively stained with alpha-naphtyl butyrate esterase, but not with naphthol AS-D chloroacetate esterase, myeloperoxidase, and periodic acid-Schiff reagent. Cell surface marker analysis revealed that the cells were CD4, CD11a, CD11c, CD13, CD14, CD18, CD33, and HLA-DR positive. Karyotype analysis revealed near diploidy (47 XX) and a translocation t(11;19) was found. When treated with 12-o-tetradecanoylphorbol 13-acetate, KP-1 cells became tightly adherent, showed the enhanced reactivity for alpha-naphtyl butyrate esterase, and produced several monokines such as IL-1 beta, tumor necrosis factor-alpha, and macrophage colony-stimulating factor. Immunoelectron microscopy demonstrated that the human macrophage scavenger receptor was expressed after 12-o-tetradecanoylphorbol-13-acetate treatment, and the cells accumulated a large amount of cholesterol esters in the presence of acetylated LDL. Compared with another human monocytic leukemia cell line, THP-1, KP-1 expressed scavenger receptor and accumulated cholesterol ester more rapidly in the presence of 12-o-tetradecanoyl phorbol-13-acetate and acetylated LDL. Scatchard analysis using 125I-labeled acetylated LDL revealed a typical saturation curve with an apparent kd of 1.7 x 10(-7) M and 3400 binding sites per cell. KP-1 retained the characteristics of monocyte-macrophage lineage cells and will facilitate the in vitro studies of the pathologic and physiologic roles of scavenger receptors.

The aetiological significance of work-load in the development of osteoarthritis of the distal interphalangeal joint

The incidence of Heberden's nodes was determined in three groups of Japanese women with different occupations to investigate the role of work-load in their pathogenesis. School cooks (n = 260), each of whom prepared 150 to 450 lunches daily, pre-school cooks (n = 222), each of whom prepared 30 to 80 lunches daily, and municipal employees (n = 298) underwent physical examination and X-ray of the hand if pathology was present. The incidence of Heberden's nodes and X-ray incidence of osteoarthritis was 19.2% and 13.5%, 8.6% and 5.4%, 5.9% and 2.0% among school cooks, pre-school cooks and municipal workers, respectively. The incidence of Heberden's nodes and osteoarthritis was significantly higher among school cooks. These findings support the concept that work-load is an aetiological factor in the pathogenesis of Heberden's nodes and also support Radin's hypothesis that women's daily work pattern explains the increased incidence of DIP joint osteoarthritis in women.

Cytotoxicity of Porphyromonas gingivalis toward cultured human gingival fibroblasts

Direct cytotoxicity of black-pigmented anaerobic rods was studied on the confluent monolayer of human gingival fibroblasts in vitro. Only strains of Porphyromonas gingivalis caused morphological alteration (cell-rounding) and notable depression of viability of fibroblasts. To determine the location of the cytotoxicity, bacterial surface components, i.e., outer membrane, lipopolysaccharide, fimbriae and outer membrane vesicles were prepared from P. gingivalis and their cytotoxicity was assessed. Among these preparations, only outer membrane vesicles are supposed to have high affinity to human gingival fibroblasts, and the cytotoxicity of outer membrane vesicles was found to be much stronger than that of the other constituents. This cytotoxic factor seemed to consist largely of protein and to be associated with the enzyme activity of outer membrane vesicles. The effects of some protease inhibitors and L-cysteine on the cytotoxicity of outer membrane vesicles suggest that the mechanism of cell-rounding is different from that of cell death.

[The surgical management of renal cell carcinoma involving the right atrium]

Between January 1985 and November 1992, 12 patients with renal cell carcinoma involving the inferior vena cava were evaluated and treated at this hospital. In 4 of the 12 patients (33%), the tumors extended into the right atrium. These 4 patients underwent radical nephrectomy with tumor thrombus extraction. Of the 4 patients one had metastases to regional lymph nodes, but no patient had distant metastases. We used a cardiopulmonary bypass and a right atriotomy in all patients for the removal of thrombus under direct vision. We also performed in the intra-operative transesophageal ultrasonography for monitoring of intra-atrial thrombus. The average blood loss during operation was 10,430 ml. One of these patients died in the postoperative period and the other patient died from inferior vena caval emboli without long term sequelae. However, the remaining 2 patients of this group are free of disease, with a mean follow-up of 21 months. Although the numbers are small, these results suggest that patients with intra-atrial tumor thrombus had a worse prognosis than those with other types of vena cava tumor thrombus. One reason for this poor prognosis is due to the complicated surgical management and we believe that a complete removal of tumor thrombus and a complete vascular control are key points of this operation.

Biomechanical analysis of radial wedge osteotomy for the treatment of Kienböck's disease

Biomechanical analysis of force transmission through the lunate was performed with the use of a two-dimensional mathematical model to evaluate the usefulness of radial wedge osteotomy, a procedure that decreases radial inclination, in the treatment of Kienböck's disease. The forces acting on the carpal bones were compared before and after radial wedge osteotomy in 29 patients with Kienböck's disease. The average osteotomy angle was 9.6 degrees. The total force through the lunocapitate joint at the midcarpal level was decreased by 23%, while the total force through the radiolunate and ulnolunate joints at the radioulnocarpal level was decreased by 10% and 36%, respectively. These changes correlated directly with the osteotomy angle and demonstrate decompression of the lunate by radial wedge osteotomy.

Changes in carpal alignment following radial osteotomy for Kienböck's disease

Changes in carpal alignment following radial osteotomy were studied in 30 patients with Kienböck's disease. The carpal height ratio and carpal-ulnar distance ratio were significantly less in wrists with Kienböck's disease than unaffected wrists. This observation implies proximal-ulnar translation of the capitate. In addition, the lunate-covering ratio increased significantly, reflecting radial translation of the lunate. Radial osteotomy corrected ulnar translation of the capitate and increased the radial translation of the lunate, thus increasing the lunate-covering ratio. The increased lunate-covering ratio is believed to increase the area of distribution of the axial load through the lunate by increasing the contact area with the radius. The satisfactory clinical outcome of radial osteotomy is believed to be due to this effect on carpal alignment.

[Risk factors for coronary artery disease in Japanese patients with chronic renal failure]

We examined the records of 101 Japanese patients with chronic renal failure (CRF) to determine the influence of established risk factors on the incidence of coronary artery disease (CAD). CAD was found in 25 patients (myocardial infarction in 18, significant coronary artery stenosis by coronary angiogram in 16). In patients with CAD, there were significantly more male (80% vs 58%, p < 0.05), more smokers (80% vs 41%, p < 0.0005), more diabetics (68% vs 32%, p < 0.005) and more hypertensives (92% vs 76%, p < 0.05). However, lipoprotein (a), high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, or triglycerides were not significantly different between CAD group and control group. When significant risk factors were entered into a stepwise logistic regression analysis, we found a history of smoking (p = 0.0025) and the presence of diabetes (p = 0.0141) to be independent risk factors for the presence of CAD in Japanese patients with CRF.

Different appearance of gamma delta T cells during salmonellosis between Ityr and Itys mice

Ity gene, which is believed to be a single gene on proximal mouse chromosome 1, determines susceptibility to Salmonella infection. We have recently demonstrated that the gamma delta T cells specific for purified protein derivative appear at the early stage after infection with Salmonella choleraesuis strain 31N-1 (avirulent strain) in mice. In the present study, we compared the appearance of the gamma delta T cells in Ityr and Itys mice after infection with S. choleraesuis in an attempt to elucidate the role of the gamma delta T cells in the in vivo effect of the Ity locus on murine salmonellosis. The numbers of gamma delta T cells in the peritoneal cavity and liver were significantly larger in DBA/2 (Ityr) mice than those in BALB/c (Itys) mice after infection with a sublethal dose of S. choleraesuis. C.D2 Ityr mice, which are BALB/c mice with Ityr allele, also showed a significant increase in the number of the gamma delta T cells at the early stage after infection. Similar results in different appearances of the gamma delta T cells could be obtained between BALB/c and DBA/2 mice after infection with Mycobacterium bovis, bacillus Calmette-Guérin. The peritoneal adherent cells of DBA/2 mice infected with S. choleraesuis, which expressed a large amount of heat shock/stress protein (hsp) homologous to the mycobacterial 65-kDa hsp, induced significantly higher level of expansion of the peritoneal gamma delta T cells in normal mice in vivo and in vitro than did those of BALB/c mice infected with S. choleraesuis, which expressed a lesser amount of the hsp. These results suggest that the Ity locus may be closely related to the expression of hsp by macrophages after infection with Salmonella, which in turn stimulate the gamma delta T cells in the host during an early phase of salmonellosis.

Different appearance of gamma delta T cells during salmonellosis between Ityr and Itys mice

Ity gene, which is believed to be a single gene on proximal mouse chromosome 1, determines susceptibility to Salmonella infection. We have recently demonstrated that the gamma delta T cells specific for purified protein derivative appear at the early stage after infection with Salmonella choleraesuis strain 31N-1 (avirulent strain) in mice. In the present study, we compared the appearance of the gamma delta T cells in Ityr and Itys mice after infection with S. choleraesuis in an attempt to elucidate the role of the gamma delta T cells in the in vivo effect of the Ity locus on murine salmonellosis. The numbers of gamma delta T cells in the peritoneal cavity and liver were significantly larger in DBA/2 (Ityr) mice than those in BALB/c (Itys) mice after infection with a sublethal dose of S. choleraesuis. C.D2 Ityr mice, which are BALB/c mice with Ityr allele, also showed a significant increase in the number of the gamma delta T cells at the early stage after infection. Similar results in different appearances of the gamma delta T cells could be obtained between BALB/c and DBA/2 mice after infection with Mycobacterium bovis, bacillus Calmette-Guérin. The peritoneal adherent cells of DBA/2 mice infected with S. choleraesuis, which expressed a large amount of heat shock/stress protein (hsp) homologous to the mycobacterial 65-kDa hsp, induced significantly higher level of expansion of the peritoneal gamma delta T cells in normal mice in vivo and in vitro than did those of BALB/c mice infected with S. choleraesuis, which expressed a lesser amount of the hsp. These results suggest that the Ity locus may be closely related to the expression of hsp by macrophages after infection with Salmonella, which in turn stimulate the gamma delta T cells in the host during an early phase of salmonellosis.

MR imaging findings of tremors associated with lesions in cerebellar outflow tracts: report of two cases

Two cases with severe tremors were studied by means of electromyograms using surface electrodes and also by magnetic resonance (MR) imaging. The first case was associated with multiple sclerosis and demonstrated a severe postural cerebellar tremor and an alternate activation of antagonist muscles in the right arm. The second case, with hemorrhage in the brainstem, demonstrated a severe tremor at rest and mixed synchronous and alternating activation of antagonist muscles in the left forearm. MR imaging studies localized lesions possibly responsible for these tremors. In the first case a lesion was located in the superior cerebellar peduncle just under the decussation, and in the second case a lesion was found between the red nucleus and the thalamus, with possible involvement of both the cerebellothalamic and nigrostriatal pathways. The first case accords with the theory that a lesion located in the dentate nucleus and its projection can cause severe postural cerebellar tremor. The lesion demonstrated in the second case may be responsible for "cerebellar tremor at rest" or "static (resting) cerebellar tremor."

Scaphoid non-union: factors affecting the functional outcome of open reduction and wedge grafting with Herbert screw fixation

50 patients with scaphoid non-union were treated by open reduction, anterior wedge bone grafting and internal fixation using the Herbert screw. Intra-operative image intensifier control enabled us to insert the screw into the scaphoid accurately. An excellent or good functional outcome was less likely when more than 5 years had elapsed since injury, the non-union was in the proximal third, when sclerosis of the proximal fragment was present, and when reduction of carpal and scaphoid deformity was unsatisfactory. These four factors are believed to be the primary determinants affecting the functional results of the surgical treatment of scaphoid non-union, even when bony union is achieved.

Radial osteotomy for Kienböck's disease evaluated by magnetic resonance imaging. 24 cases followed for 1-3 years

24 patients with Kienböck's disease were followed with magnetic resonance imaging (MRI) for 1-3 years. 9 patients were treated with radial shortening, 10 with radial wedge osteotomy and 5 patients were treated non-operatively. Signal intensity of the lunate on T1-weighted or T2-weighted images increased postoperatively in all operated on patients, and normal or near-normal signal intensity was observed in 9 patients on T1-weighted images and in 15 patients on T2-weighted images postoperatively. Signal intensity did not increase in any patient treated non-operatively. The postoperative increase in signal intensity on MRI following radial shortening and radial wedge osteotomy presumably is due to revascularization of the lunate.