Transcatheter arterial embolization for traumatic injury to the pharyngeal branch of the ascending pharyngeal artery: Two case reports

BACKGROUND

The ascending pharyngeal artery (APhA) comprises the pharyngeal trunk (PT) and neuromeningeal trunk. The PT feeds the nasopharynx and adjacent tissue, which potentially connects with the sphenopalatine artery (SPA), branched from the internal maxillary artery (IMA). Due to its location deep inside the body, the PT is rarely injured by trauma. Here, we present two cases that underwent transcatheter arterial embolization (TAE) of the PT of the APhA due to trauma and iatrogenic procedure.

CASE SUMMARY

Case 1 is a 49-year-old Japanese woman who underwent transoral endoscopy under sedation for a medical check-up. The nasal airway was inserted as glossoptosis occurred during sedation. Bleeding from the nasopharynx was observed during the endoscopic procedure. As the bleeding continued, the patient was referred to our hospital for further treatment. Contrast-enhanced computed tomography (CT) demonstrated extravasation in the nasopharynx originating from the right Rosenmuller fossa. TAE was performed and the extravasation disappeared after embolization. Case 2 is a 28-year-old Japanese woman who fell from the sixth floor of a building and was transported to our hospital. Contrast-enhanced CT demonstrated a complex facial fracture accompanying extravasation in the left pterygopalatine fossa to the nasopharynx. Angiography demonstrated an irregular third portion of the IMA. As angiography after TAE of the IMA demonstrated extravasation from the PT of the APhA, additional TAE to the artery was performed. The bleeding stopped after the procedure.

CONCLUSION

Radiologists should be aware that the PT of the APhA can be a bleeding source, which has a potential connection with the SPA.

Middle mesenteric artery: Angiographic and three-dimensional computed tomography findings

The middle mesenteric artery, also known as the third mesenteric artery, is a very rare anomaly. Several anatomical variations of middle mesenteric artery have been reported; in these reports, the right colic artery and/or middle colic artery often originate directly from the aorta. Here, we report a middle mesenteric artery in which the middle colic artery originated directly from the abdominal aorta. We also provide three-dimensional computed tomography and angiography findings and discuss anatomical and embryological considerations.

196 GLUTATHIONE S-TRANSFERASE THETA1 (GSTT1) IS DIFFERENTIALLY REGULATED FROM OTHER GLUTATHIONE S-TRANSFERASES IN GRANULOSA CELLS

Oxidative stress is a major source of aging that damages genomic and mitochondrial DNA, causing female reproductive disorders. Glutathione S-transferases (GST) are known to detoxify the metabolites of genotoxic molecules to more water-soluble and readily excretable forms. Therefore, most GST have been considered to be down-regulated by aging. We recently demonstrated that only GSTT1 is up-regulated in granulosa cells from aged, infertile patients and aged mice, although other kinds of GST are down-regulated in these cells (Ito et al. 2008 Fertil. Steril. 90, 1026–1035). Measurement of the GSTT1 level in granulosa cells binding to the patient’s oocytes could be used in the selection of oocytes of high quality, meaning that the GSTT1 level in granulosa cells could be a good indicator of age-related infertility. To do that, an understanding of the concrete relationship between aging and GSTT1 up-regulation is necessary. However, the regulation mechanism of GSTT1 in granulosa cells remains unclear. In the present study, we attempted to examine the difference in expression mechanisms between GSTT1 and other GST. First, the expression patterns of GSTT1 and GSTP (a major member of the GST) in aged granulosa cells from patients were observed by immunostaining. The GSTT1 was up-regulated (young: 25 to 34 years old, N = 9; aged: 38 to 43 years old, N = 12; P < 0.05) but the GSTP was down-regulated (young: 28 to 30 years, N = 5; aged: 38 to 42 years, N = 7; P < 0.05) in the aged group. Nuclear factor erythroid 2 p45-related factor 2 (Nrf2) is a transcription factor that regulates the expression of most GST, so in the next experiment, we examined the expression patterns of GSTT1 and GSTP in granulosa cells from Nrf2-disrupted (Nrf2–/–) mice by immunostaining. The GSTP was down-regulated in granulosa cells of Nrf2–/– mice compared with those of Nrf2+/– mice, although a significant difference was not observed in GSTT1. In addition, we confirmed these results by using mouse embryonic fibroblasts (MEF) from Nrf2–/– and Nrf2+/– mice, and the same results were obtained. Our previous experiment showed that GSTT1 was induced by FSH in human granulosa-like tumour cells (KGN cells). We analysed the expression level of other genes in FSH-stimulated KGN cells. The transcription levels of GSTP and Nrf2 were not induced by FSH. These results suggest that the expression of GSTT1 is not regulated by Nrf2 and is differentially regulated from other GST. The difference in regulation mechanisms between GSTT1 and other GST may result in the up-regulation of GSTT1 in the aging granulosa cells, and it may contribute to the constitution of the diagnosis of oocyte quality using the GSTT1 measurement.

Apnoea–Hypopnoea Index during Rapid Eye Movement and Non-Rapid Eye Movement Sleep in Obstructive Sleep Apnoea

This study investigated the differences in apnoea-hypopnoea index (AHI) during rapid eye movement (REM) sleep (AHI-REM) and AHI during non-REM (NREM) sleep (AHI-NREM) in patients with obstructive sleep apnoea (OSA). Nocturnal polysomnography was performed in 102 Japanese OSA patients and their AHI along with a variety of other factors were retrospectively evaluated. Regardless of the severity of AHI, mean apnoea duration was longer and patients' lowest recorded oxygen saturation measured by pulse oximetry was lower during REM sleep than during NREM sleep. Approximately half of the patients ( n = 50) had a higher AHI-NREM than AHI-REM. In subjects with AHI ≤ 60 events/h, AHI-NREM was significantly higher than AHI-REM. On multivariate logistic regression, severe AHI ≤ 30 events/h was the only predictor of a higher AHI-NREM than AHI-REM. This may indicate that important, but unknown, factors related to the mechanism responsible for the severity of OSA are operative during NREM sleep.

Laceration of gastric mucosa associated with dialysis-related amyloidosis

We report a 72-year-old female on long-term hemodialysis, who was admitted to the hospital because of hematemesis. On emergency laparotomy, pylorogastrectomy was performed. The resected specimen showed a giant hematoma and traversing fissure along the lesser curvature of the body of the stomach. Histologically, the specimen showed wide hematoma formation and amyloid deposits in the submucosal layer, especially in the wall of blood vessels. These deposits reacted positively to antihuman beta2-microglobulin antibody. The post-operative course was favorable, and the patient was discharged on the 35th hospital day. In this case, the laceration site on the gastric mucosa was almost intact and did not demonstrate ischemic change, suggesting that the giant hematoma was caused by submucosal vessel rupture, which led to the gastric mucosa laceration. To our knowledge, this is the first case of gastric mucosa laceration associated with dialysis-related amyloidosis.

Structure of Urtica dioica agglutinin isolectin I: dimer formation mediated by two zinc ions bound at the sugar-binding site

Ultica dioica agglutinin, a plant lectin from the stinging nettle, consists of a total of seven individual isolectins. One of these structures, isolectin I, was determined at 1.9 A resolution by the X-ray method. The crystals belong to the space group P2(1) and the asymmetric unit contains two molecules related by local twofold symmetry. The molecule consists of two hevein-like chitin-binding domains lacking distinct secondary structure, but four disulfide bonds in each domain maintain the tertiary structure. The backbone structure of the two independent molecules is essentially identical and this is similarly true of the sugar-binding sites. In the crystal, the C-terminal domains bind Zn(2+) ions at the sugar-binding site. Owing to their location near a pseudo-twofold axis, the two zinc ions link the two independent molecules in a tail-to-tail arrangement: thus, His47 of molecule 1 and His67 of molecule 2 coordinate the first zinc ion, while the second zinc ion links Asp75 of molecule 1 and His47 of molecule 2.

Role of chemical mediators in airway hyperresponsiveness in an asthmatic model

BACKGROUND

Airway hyperresponsiveness (AHR) is one of the characteristic features of human asthma. The presence of AHR and the precise mechanisms immediately after establishment of sensitization in guinea pigs are unclear, although there are many reports showing allergen exposure that causes an increase in bronchial responsiveness associated with eosinophil influx into the airway in sensitized guinea pigs.

OBJECTIVE

We investigated the inhibitory effects on AHR to histamine of ONO-1078, a leukotriene antagonist; indomethacin, a cyclooxygenase inhibitor; S-145, a thromboxane A(2) (TXA(2)) antagonist, and Y-24180, a platelet-activating factor (PAF) antagonist, to assess the involvement of chemical mediators in AHR employing ovalbumin (OA) sensitized guinea pig models.

METHODS

Male Hartley guinea pigs were used. Each group comprised 4-7 animals. The animals were sensitized to OA, injecting intraperitoneally 30 mg of cyclophosphamide and 2,000 microg of OA together with 100 mg of aluminum hydroxide as the adjuvant. The guinea pigs were artificially ventilated via a cannula using a small-animal respirator after intraperitoneal anesthesia with pentobarbital sodium for tracheotomy. The pressure at the airway opening (PAO) was measured using a differential pressure transducer, and a differential pressure of peak PAO (peak DeltaPAO) at inspiratory phase as an overall index of bronchial response to bronchoactive agents was used. While being artificially ventilated, the animals were exposed to physiological saline solution containing various concentrations of histamine (4.9, 9.8, 20, 39, 78, and 156 microg/ml) by inhalation for 30 s at 3-min intervals. Determinations were made at 1 min after each inhalation. The chemical mediators were each (30 mg/kg of ONO-1078, 3 mg/kg of S-1452, and 1 mg/kg of Y-24180) administered orally to sensitized guinea pigs, and the airway response to histamine was assessed. Each group comprised 4-7 animals.

RESULTS

The airway response to histamine was significantly greater in the sensitized group than in the nonsensitized group at histamine concentrations of 36 (p < 0.05), 78, and 156 mg/ml (p < 0.01). Leukotrienes C(4) and D(4): 30 mg/kg of ONO-178 did not show any inhibitory effect on airway response to inhaled histamine. Cyclooxygenase: 5 mg/kg of indomethacin did not show any inhibitory effect on the airway response to inhaled histamine. TXA(2): the AHR to inhaled histamine at doses of 9.8, 39, 78, and 156 microg/ml was significantly inhibited by prior administration of 3 mg/kg of S-1452. PAF: the AHR to inhaled histamine at doses of 9.8, 39, and 78 microg/ml was significantly inhibited by prior administration of 1 mg/kg of Y-24180.

CONCLUSIONS

S-1452 (3 mg/kg) and Y-24180 (1 mg/kg) significantly inhibited AHR to histamine, while ONO-108 (30 mg/kg) and indomethacin (5 mg/kg) did not. The results suggest that TXA(2) and PAF are involved in AHR in OA-sensitized guinea pigs.

Effect of AA-2414 on early and late bronchial responses in actively sensitized guinea-pigs

The effect of a new thromboxane A2 receptor antagonist, AA-2414, (+/-)-7-(3,5,6-trimethyl-1,4-benzoquinon-2-yl)-7-phenylheptanoic acid, on dual bronchoconstriction and airway hyper-reactivity in actively sensitized guinea-pigs was investigated. Immediate and late bronchial responses were seen 1-10 min and 4-7 h, respectively, after inhalation of antigen. In guinea-pigs pretreated with AA-2414, 5 mg/kg orally, the immediate bronchial response was inhibited. An administration of AA-2414 inhibited the late bronchial response. The numbers of eosinophils, neutrophils and macrophages, but not of lymphocytes, in bronchoalveolar lavage fluid were increased at 4 h after antigen inhalation. AA-2414 did not affect the numbers of total cells, eosinophils, neutrophils or macrophages. Sensitized guinea-pigs showed a significant airway hyperreactivity to inhaled histamine, which was not influenced by an administration of AA-2414. Luminol-dependent chemiluminescence of airway-infiltrated cells from sensitized guinea-pigs stimulated with A23187 was slightly inhibited by AA-2414. These results show that AA-2414 inhibits the late asthmatic response and the production of oxygen radicals from airway-infiltrated cells.

Angiographically verified progression of moyamoya disease in an adult. Case report

The authors present the case of a 37-year-old man with definite moyamoya disease in whom angiographic findings drastically changed. The patient presented with left hemiparesis due to lacunar infarction. Angiography initially disclosed a narrow right carotid artery (CA) siphon and severe stenosis of the horizontal segment of the left middle cerebral artery. Four years later, the patient experienced right-central facial paresis, which developed because of a small putaminal hematoma. Angiography results demonstrated occlusion of the internal CA siphons bilaterally, with moyamoya vessels. It therefore appears that in some adults, moyamoya disease is accompanied by very progressive vascular changes.

Construction of a generalized simulator for multi-cellular organisms and its application to SMAD signal transduction

In this paper, we report development of a generalized simulation system based on ordinary differential equations for multi-cellular organisms, and results of the analysis on a Smad signal transduction cascade. The simulator implements intra-cellular and extra-cellular molecular processes, such as protein diffusion, ligand-receptor reaction, biochemical reaction, and gene expression. It simulates the spatio-temporal patterning in various biological phenomena for the single and multi-cellular organisms. In order to demonstrate the usefulness of the simulator, we constructed a model of Drosophila's Smad signal transduction, which includes protein diffusion, biochemical reaction and gene expression. The results suggest that the presence of negative feedback mechanism in the Smad pathway functions to improve the frequency response of the cascade against changes in the signaling.

Chemically prepared hevein domains: effect of C-terminal truncation and the mutagenesis of aromatic residues on the affinity for chitin

Chemically prepared hevein domains (HDs), N-terminal domain of an antifungal protein from Nicotiana tabacum (CBP20-N) and an antimicrobial peptide from Amaranthus caudatus (Ac-AMP2), were examined for their affinity for chitin, a beta-1,4-linked polymer of N-acetylglucosamine. An intact binding domain, CBP20-N, showed a higher affinity than a C-terminal truncated domain, Ac-AMP2. The formation of a pyroglutamate residue from N-terminal Gln of CBP20-N increased the affinity. The single replacement of any aromatic residue of Ac-AMP2 with Ala resulted in a significant reduction in affinity, suggesting the importance of the complete set of three aromatic residues in the ligand binding site. The mutations of Phe18 of Ac-AMP2 to the residues with larger aromatic rings, i.e. Trp, beta-(1-naphthyl)alanine or beta-(2-naphthyl)alanine, enhanced the affinity, whereas the mutation of Tyr20 to Trp reduced the affinity. The affinity of an HD for chitin might be improved by adjusting the size and substituent group of stacking aromatic rings.

The blood supply of the lateral epiphyseal arteries in Perthes' disease

We performed superselective angiography in 28 hips in 25 patients with Perthes' disease in order to study the blood supply of the lateral epiphyseal arteries (LEAs). Interruption of the LEAs at their origin was observed in 19 hips (68%). Revascularisation in the form of numerous small arteries was seen in ten out of 11 hips in the initial stage of Perthes' disease, in seven of eight in the fragmentation stage and in five of nine in the healing stage. Penetration of mature arteries into the depths of the epiphysis was seen in four of nine hips in the healing stage. Vascular penetration was absent in the weight-bearing portion of the femoral head below the acetabular roof. Interruption of the posterior column artery was seen where it passed through the capsule in seven hips when they lay either in internal rotation or in abduction with internal rotation. We suggest that in Perthes' disease the blood supply of the LEAs is impaired at their origin and that revascularisation occurs from this site by ingrowth of small vessels into the femoral epiphysis. This process may be the result of recurrent ischaemic episodes.

The blood supply of the lateral epiphyseal arteries in Perthes’ disease

We performed superselective angiography in 28 hips in 25 patients with Perthes’ disease in order to study the blood supply of the lateral epiphyseal arteries (LEAs). Interruption of the LEAs at their origin was observed in 19 hips (68%). Revascularisation in the form of numerous small arteries was seen in ten out of 11 hips in the initial stage of Perthes’ disease, in seven of eight in the fragmentation stage and in five of nine in the healing stage. Penetration of mature arteries into the depths of the epiphysis was seen in four of nine hips in the healing stage. Vascular penetration was absent in the weight-bearing portion of the femoral head below the acetabular roof. Interruption of the posterior column artery was seen where it passed through the capsule in seven hips when they lay either in internal rotation or in abduction with internal rotation.

We suggest that in Perthes’ disease the blood supply of the LEAs is impaired at their origin and that revascularisation occurs from this site by ingrowth of small vessels into the femoral epiphysis. This process may be the result of recurrent ischaemic episodes.

Crystal structures of Urtica dioica agglutinin and its complex with tri-N-acetylchitotriose

Urtica dioica agglutinin is a small plant lectin that binds chitin. We purified the isolectin VI (UDA-VI) and crystal structures of the isolectin and its complex with tri-N-acetylchitotriose (NAG3) were determined by X-ray analysis. The UDA-VI consists of two domains analogous to hevein and the backbone folding of each domain is maintained by four disulfide bridges. The sequence similarity of the two domains is not high (42 %) but their backbone structures are well superimposed except some loop regions. The chitin binding sites are located on the molecular surface at both ends of the dumbbell-shape molecule. The crystal of the NAG3 complex contains two independent molecules forming a protein-sugar 2:2 complex. One NAG3 molecule is sandwiched between two independent UDA-VI molecules and the other sugar molecule is also sandwiched by one UDA-VI molecule and symmetry-related another one. The sugar binding site of N-terminal domain consists of three subsites accommodating NAG3 while two NAG residues are bound to the C-terminal domain. In each sugar-binding site, three aromatic amino acid residues and one serine residue participate to the NAG3 binding. The sugar rings bound to two subsites are stacked to the side-chain groups of tryptophan or histidine and a tyrosine residue is in face-to-face contact with an acetylamino group, to which the hydroxyl group of a serine residue is hydrogen-bonded. The third subsite of the N-terminal domain binds a NAG moiety with hydrogen bonds. The results suggest that the triad of aromatic amino acid residues is intrinsic in sugar binding of hevein-like domains.

Dual-phase response model for bronchial asthma

The authors have successfully developed an animal model of dual-phase bronchial responses and very high IgG titer by sensitizing Hartley-strain male guinea pigs. Specific airway resistance, which was determined in a two-chamber body plethysmograph, was elevated to sevenfold during immediate response, followed by a late phase response with a smaller but marked elevation in resistance. Furthermore, hematological and histological examinations revealed that the total cell count increased in BAL obtained during both immediate and late bronchial responses as compared to pre-OVA challenges. A significant increase in BAL eosinophils was present only for the late bronchial samples, and this finding was supported by histological examination.

Inhibitory effect of TMK-688 on late asthmatic responses as well as T-cell and eosinophilic infiltration in guinea pigs with asthmatic reactions

The effects of an oral anti-allergic agent, TMK-688, which inhibits 5-lipoxygenase, at doses of 3.2 and 10 mg/kg were studied in guinea pigs with dual-phase asthmatic response. We previously observed that pretreatment with TMK-688 inhibited the late asthmatic response (LAR) induced by ovalbumin inhalation exposure. The present study focused on the effect of TMK-688 on infiltration by T-cells and eosinophils. TMK-688 inhibited both T-cell and eosinophilic infiltration. These findings suggest that TMK-688 is effective in inhibiting infiltration of T-cells and eosinophilic chemotaxis, and thereby suppresses LAR.

Protein-carbohydrate interactions in human lysozyme probed by combining site-directed mutagenesis and affinity labeling

The synergism between apolar and polar interactions in the carbohydrate recognition by human lysozyme (HL) was probed by site-directed mutagenesis and affinity labeling. The three-dimensional structures of the Tyr63-->Leu mutant HL labeled with 2',3'-epoxypropyl beta-glycoside of N,N'-diacetylchitobiose (L63-HL/NAG-NAG-EPO complex) and the Asp102-->Glu mutant HL labeled with the 2',3'-epoxypropyl beta-glycoside of N-acetyllactosamine were revealed by X-ray diffraction at 2.23 and 1.96 A resolution, respectively. Compared to the wild-type HL labeled with the 2', 3'-epoxypropyl beta-glycoside of N,N'-diacetylchitobiose, the N-acetylglucosamine residue at subsite B of the L63-HL/NAG-NAG-EPO complex markedly moved away from the 63rd residue, with substantial loss of hydrogen-bonding interactions. Evidently, the stacking interaction with the aromatic side chain of Tyr63 is essential in positioning the N-acetylglucosamine residue in the productive binding mode. On the other hand, the position of the galactose residue in subsite B of HL is almost unchanged by the mutation of Asp102 to Glu. Most hydrogen bonds, including the one between the carboxylate group of Glu102 and the axial 4-OH group of the galactose residue, were maintained by local movement of the backbone from residues 102-104. In both structures, the conformation of the disaccharide was conserved, reflecting an intrinsic conformational rigidity of the disaccharides. The structural analysis suggested that CH-pi interactions played an important role in the recognition of the carbohydrate residue at subsite B of HL.

Posterior rotational osteotomy for the treatment of femoral head osteonecrosis

Posterior rotational osteotomy in 46 hips of 39 patients with femoral head osteonecrosis was reviewed radiographically and clinically after 2-12 years of follow-up (mean 5 years). The age of the patients at the time of surgery ranged from 18 to 60 years, with a mean of 35 years. There were 18 women and 21 men. The cause of the osteonecrosis was steroid administration in 14, alcohol abuse in 5, trauma in 16, and no apparent risk factor in 4. According to the Ficat staging system, 2 hips were stage II, 30 hips III, and 14 hips stage IV. All hips had an extensive lesion. Forty-one hips showed less than 1/3 noncollapsed posterior living area, which was a contraindication for traditional anterior rotational osteotomy. The posterior rotational angle was 60-180 deg with an mean of 127 deg. Recollapse of the final follow-up anteroposterior radiograph was prevented in 36 hips (78%). Progressive joint space narrowing was found in 12 hips (26%). Of these hips, 9 suffered recollapse, while the remaining 3 hips did not. Clinically, 32 hips (70%) showed excellent or good results (both hips in stage II, 23 of 30 hips in stage III, 7 of 14 hips in stage IV. A fair or poor result was seen in 14 hips (30%)). These results suggest that posterior rotational osteotomy is effective in delaying the progression of degeneration for large necrotic lesions, especially in young patients. Extent of rotation is limited to 150 deg because of limitations of bone quality. The indications should be refined further, and longer term follow-up is necessary.

Human lysozyme secretion increased by alpha-factor pro-sequence in Pichia pastoris

To get high level secretion of human lysozyme in Pichia pastoris, the following three signal sequences and one prepro sequence were evaluated: chicken lysozyme signal peptide, leucine-rich artificial signal peptide, Saccharomyces invertase signal peptide, and Saccharomyces prepro sequence of alpha factor (MF-alpha Prepro). Transformants harboring a lysozyme gene with MF-alpha Prepro secreted 20-fold more lysozyme than those harboring the lysozyme gene with any one of the other three signal sequences. Three mutant leader sequences derived from MF-alpha Prepro were constructed to discover the function of the pro region. The secretion was dramatically decreased by eliminating the pro region of MF-alpha Prepro. In contrast, MF-alpha Prepro with the EAEAEA sequence directed the secretion of an equivalent level of lysozyme having the extra amino acids (EAEAEA) in its N-terminus. For the effective secretion of native human lysozyme, MF-alpha Prepro without any spacer sequences was most suitable. The secreted protein by MF-alpha Prepro construct was identical with the authentic human lysozyme, judging from N-terminal amino acid sequencing and molecular mass spectrometric and crystallographic analysis.

Prevention of aerobic spoilage of maize silage by a genetically modified killer yeast, Kluyveromyces lactis, defective in the ability to grow on lactic acid

In this study, we propose a new process of adding a genetically modified killer yeast to improve the aerobic stability of silage. Previously constructed Kluyveromyces lactis killer strain PCK27, defective in growth on lactic acid due to disruption of the gene coding for phosphoenolpyruvate carboxykinase, a key enzyme for gluconeogenesis, inhibited the growth of Pichia anomala inoculated as an aerobic spoilage yeast and prevented a rise in pH in a model of silage fermentation. This suppressive effect of PCK27 was not only due to growth competition but also due to the killer protein produced. From these results, we concluded that strain PCK27 can be used as an additive to prolong the aerobic stability of maize silage. In the laboratory-scale experiment of maize silage, the addition of a killer yeast changed the yeast flora and significantly reduced aerobic spoilage.

Effects of saiboku-to on dual-phase bronchoconstriction in asthmatic guinea pigs

In recent years, bronchial asthma has come to be regarded pathologically as a chronic inflammatory disease of the respiratory tract. Inhalational steroids and antiinflammatory drugs are recognized as being effective against bronchial asthma. In this study, the effects of Saiboku-to, a Chinese herbal (Kampo) formulation, were investigated on asthmatic guinea pigs sensitized to ovalbumin (OA). Following 7-day administration of Saiboku-to (500 micrograms/kg), the late asthmatic response (LAR) to an antigen challenge was found to be inhibited. The number of eosinophils in fluid obtained by bronchoalveolar lavage (BAL) 4 h after antigen challenge was decreased while the infiltration of eosinophils and T-lymphocytes into the lung parenchyma was inhibited. These findings suggest that Saiboku-to has the potential to become a useful drug in the treatment of bronchial asthma.

Effects of saiboku-to on the survival of human eosinophils

In recent years, bronchial asthma has come to be regarded as a chronic inflammatory disease of the respiratory tract, with mast cells, lymphocytes and eosinophils playing important roles in its pathogenesis. Proteins contained in eosinophil granules, especially major basic protein (MBP), eosinophil cationic protein (ECP), eosinophil-derived neurotoxin (EDN) and eosinophil peroxidase (EPO), can cause tissue injury. When stimulated, eosinophils release mediators such as leukotriene C4 (LTC4) and platelet activating factors (PAF). Thus, they are recognized as effector cells that are actively involved in the development of allergic inflammation. In this study, eosinophils from healthy volunteers were used to investigate the effects of Saiboku-to on eosinophils whose survival had been prolonged through stimulation with eosinophil-activating cytokines such as interleukin (IL)-3, IL-5 and granulocyte macrophage colony stimulating factors (GM-CSF). As a result, the cytokine-enhanced survival of eosinophils was significantly shortened by the addition of Saiboku-to. These findings suggest that Saiboku-to has the potential to inhibit allergic responses by directly affecting eosinophils which are related to allergic inflammation.

Crystallographic evaluation of internal motion of human alpha-lactalbumin refined by full-matrix least-squares method

The low temperature form of human alpha-lactalbumin (HAL) was crystallized from a 2H2O solution and its structure was refined to the R value of 0.119 at 1.15 A resolution by the full-matrix least-squares method. Average estimated standard deviations of atomic parameters for non-hydrogen atoms were 0.038 A for coordinates and 0.044 A2 for anisotropic temperature factors (Uij). The magnitude of equivalent isotropic temperature factors (Ueqv) was highly correlated with the distance from the molecular centroid and fitted to a quadratic equation as a function of atomic coordinates. The atomic thermal motion was rather isotropic in the core region and the anisotropy increased towards the molecular surface. The statistical analysis revealed the out-of-plane motion of main-chain oxygen atoms, indicating that peptide groups are in rotational vibration around a Calpha.Calpha axis. The TLS model, which describes the rigid-body motion in terms of translation, libration, and screw motions, was adopted for the evaluation of the molecular motion and the TLS parameters were determined by the least-squares fit to Uij. The reproduced Ueqvcal from the TLS parameters was in fair agreement with observed Ueqv, but differences were found in regions of residues, 5-22, 44-48, 70-75, and 121-123, where Ueqv was larger than Ueqvcal because of large local motions. To evaluate the internal motion of HAL, the contribution of the rigid-body motion was determined to be 42.4 % of Ueqv in magnitude, which was the highest estimation to satisfy the condition that the Uijint tensors of the internal motion have positive eigen values. The internal motion represented with atomic thermal ellipsoids clearly showed local motions different from those observed in chicken-type lysozymes which have a backbone structure very similar to HAL. The result indicates that the internal motion is closely related to biological function of proteins.

Dual affinity labeling of the active site of human lysozyme with an N-acetyllactosamine derivative: first ligand assisted recognition of the second ligand

Among the three kinds of the 2',3'-epoxypropyl beta-glycoside of disaccharides (GlcNAc-beta1,4-GlcNAc, Gal-beta1,4-GlcNAc, and Man-beta1,4-GlcNAc), the derivative of N-acetyllactosamine (Gal-beta1,4-GlcNAc-Epo) caused the dual labeling of human lysozyme (HL) most efficiently. The labeled HL was crystallized and analyzed by X-ray diffraction methodology. The X-ray analysis located the two Gal-beta1,4-GlcNAc-Epo moieties inside the catalytic cleft of HL. The attachment sites were the side-chain carboxylate groups of the catalytic residues Glu35 and Asp53 in HL. The first Gal-beta1, 4-GlcNAc-Epo moiety occupied virtually the same position as observed in the HL labeled with single Gal-beta1,4-GlcNAc-Epo molecule. The second Gal-beta1,4-GlcNAc-Epo moiety was recognized via the carbohydrate-carbohydrate interaction with the first Gal-beta1, 4-GlcNAc-Epo moiety in addition to the protein-carbohydrate interaction with the "right-side" catalytic cleft of HL through a number of hydrogen bonds including water-mediated ones as well as many van der Waals contacts. The two N-acetylglucosamine residues stacked with each other, while the two rings of galactose residues approximately shared the same plane. The dual labeling with two Gal-beta1,4-GlcNAc-Epo molecules was supposed to have occurred sequentially, which was accompanied with the alteration to the pKa of Glu35 derived from the esterification of Asp53 in the first labeling. Both asymmetric carbons in the connection parts between HL and N-acetyllactosamine moieties showed the same stereoconfiguration derived from the reaction with (2'R) stereoisomer concerning the epoxide group in the labeling reagent. The results demonstrated that the HL labeled with single Gal-beta1,4-GlcNAc-Epo was functional as a novel N-acetyllactosamine-binding protein, and the second labeling was performed by way of the first-ligand assisted recognition of the second ligand.

X-ray structure of human lysozyme labelled with 2',3'-epoxypropyl beta-glycoside of man-beta1,4-GlcNAc. Structural change and recognition specificity at subsite B

Human lysozyme (HL) labelled with the 2',3'-epoxypropyl beta-glycoside of Man-beta1,4-GlcNAc was crystallized at pH 4.5. The cell dimensions were a = 36.39, b = 116.38, c = 30.91 A and the space group was P212121. The unit cell contained four molecules (Vm = 2.18 A3 Da-1). The crystal structure was determined by molecular replacement and refined to an R value of 0.168 for 7060 reflections [|Fo| > 3sigma(F)] in the resolution range 8.0-2.1 A. A prominent shift of the Calpha-atom positions by up to 3.8 A in the region of residues 45-50 was observed compared with wild-type HL. Owing to the conformational change in this region the intermolecular contacts were altered remarkably compared to wild-type HL, explaining the difference in molecular packing. The Man-beta1,4-GlcNAc moiety occupied subsites B and C in the substrate-binding site of HL. Several differences in the hydrogen-bonded contacts between the ligand part and the protein part were observed for HL labelled with the 2',3'-epoxypropyl beta-glycoside of Man-beta1,4-GlcNAc compared with HL labelled with the corresponding derivatives of GlcNAc-beta1, 4-GlcNAc and Gal-beta1,4-GlcNAc. In contrast to the replacement of GlcNAc with Gal, the replacement of GlcNAc with Man did not sacrifice the stacking interactions with the side-chain group of Tyr63 as determined by the parallelism of the apolar face of the carbohydrate residue and the aromatic plane of the Tyr63 side chain. The 2',3'-epoxypropyl beta-glycoside of Man-beta1,4-GlcNAc exhibited almost the same affinity towards HL as Gal-beta1,4-GlcNAc, a much lower affinity than that of GlcNAc-beta1,4-GlcNAc. The difference in the protein-ligand interactions was discussed in relation to the carbo-hydrate-residue recognition specificity at subsite B of HL. The results suggested that Gln104 was a determinant for the strong recognition of GlcNAc residue at subsite B in HL.

Plasma concentrations of brain natriuretic peptide in patients with subarachnoid hemorrhage

BACKGROUND AND PURPOSE

Hyponatremia after subarachnoid hemorrhage (SAH) is commonly associated with diuresis and natriuresis, but the causes are still controversial. We investigated whether brain natriuretic peptide (BNP) was related to such hyponatremia.

METHODS

Plasma BNP concentrations were measured by immunoradiometric assay in 18 patients at 0 to 2 days (period 1), 7 to 9 days (period 2), and > 14 days (period 3) after SAH. Plasma concentrations of antidiuretic hormone (ADH), atrial natriuretic peptide (ANP), and noradrenaline were also measured during period 2.

RESULTS

The 11 patients with hyponatremia (serum sodium concentration of < 135 mEq/L) had much higher plasma BNP concentrations during each period than did healthy controls (P < 0.05), whereas the 7 patients with normonatremia did not show statistically higher values. In the patients with hyponatremia, the plasma BNP concentration during period 2 was statistically higher than that during periods 1 and 3 (P < 0.05). The plasma noradrenaline concentration during period 2 was higher in patients with hyponatremia than in those with normonatremia (P < 0.05), whereas the plasma concentrations of ADH and ANP during period 2 were not statistically different between the hyponatremic and normonatremic patients.

CONCLUSIONS

We conclude that BNP may be related to hyponatremia associated with natriuresis following SAH. The increase of noradrenaline may promote the secretion of BNP.

Effect of TYB-2285 on early and late bronchial responses and airway hyperreactivity in actively sensitized guinea pigs

1. The effect of a new antiasthmatic drug, TYB-2285 [3,5-bis (acetoxyacetylamino)-4-chlorobenzonitrile], on dual bronchoconstriction and airway hyperreactivity in actively sensitized guinea pigs was investigated. 2. Immediate and late bronchial responses were induced at 1-10 min and 4-7 hr after antigen inhalation, respectively. Guinea pigs were pretreated with TYB-2285 (300 mg kg(-1) PO, as a single dose or consecutively for 7 days). 3. The immediate bronchial response was inhibited only by a multiple administration of TYB-2285. Late bronchial response was inhibited by both administration methods. 4. The numbers of eosinophils, neutrophils and macrophages, but not lymphocytes, in the bronchoalveolar lavage fluid were increased at 4 hr after antigen inhalation. TYB-2285, given singly and consecutively, decreased the numbers of total cells, eosinophils, neutrophils and macrophages. 5. Sensitized guinea pigs showed significant airway hyperreactivity to inhaled histamine. This airway hyperresponsiveness was reversed by a single administration of TYB-2285. 6. Luminol-dependent chemiluminescence of airway-infiltrated cells was slightly inhibited by TYB-2285 (20 microg ml(-1)). 7. The present study shows that TYB-2285 inhibits late asthmatic response and airway hyperresponsiveness, presumably by inhibiting the accumulation and activation of eosinophils and other inflammatory cells.

Postcontrast magnetic resonance imaging to predict progression of traumatic epidural and subdural hematomas in the acute stage

OBJECTIVE

We investigated the possibility of predicting the progression of traumatic epidural hematomas (EDHs) and subdural hematomas (SDHs), in the acute stage, by using postcontrast magnetic resonance imaging (MRI) with gadolinium-diethylenetriaminepentaacetic acid.

METHODS

From January 1990 through December 1996, 41 patients with 43 hematomas (21 EDHs and 22 SDHs) underwent postcontrast MRI within 24 hours after injury. T1-weighted MRI was performed by using the spin echo method, after the administration of 0.1 mmol/kg gadolinium-diethylenetriaminepentaacetic acid, immediately after computed tomographic scanning.

RESULTS

All of the enhanced hematomas were enlarged, whereas nonenhanced hematomas, except for two SDHs with bleeding tendencies, remained unchanged or decreased in volume. The prediction rates for enlargement with this method were 100% (21 of 21) for EDHs and 91.0% (20 of 22) for SDHs. The sensitivity of this test in predicting enlargement was 100% (15 of 15) for EDHs and 81.8% (9 of 11) for SDHs. The specificity was 100% for both types of hematomas. The enlargement rates for diffusely enhanced hematomas were statistically greater than those for nonenhanced hematomas. All of the patients with diffusely enhanced hematomas, which were found during surgery to exhibit active bleeding points, experienced consciousness deterioration.

CONCLUSION

We conclude that diffuse enhancement indicates extravasation from broken vessels that continue to bleed and that diffusely enhancing hematomas will be rapidly enlarged. We think that postcontrast MRI can be very useful for predicting the progression of acute EDHs and SDHs.

Role of GABA receptors in the bronchial response: studies in sensitized guinea-pigs

BACKGROUND

Gamma-aminobutyric acid (GABA), an important inhibitory neurotransmitter in the mammalian central nervous system, is also found in peripheral tissues, including the lung. GABA has recently been shown to modulate the contraction of airway smooth muscle.

OBJECTIVE

We studied the effect of GABA on the contractile properties of tracheal smooth muscle by measuring the tension of the trachea isolated from non-sensitized and ovalbumin (OA)-sensitized guinea-pigs under isometric conditions.

METHODS

Guinea-pigs were sensitized by intraperitoneal doses of OA to prepare a bronchial asthma model. Tracheal spiral rings were prepared from the OA-sensitized as well as normal, non-sensitized guinea-pigs. Using the tracheal preparations, the effects of GABA and GABAa and GABAb receptor agonists (muscimol and baclofen) and antagonists (bicuculline and saclofen) on the basal tone of the trachea and on tracheal contraction induced by electrical field stimulation (EFS) were determined. The effect of GABA on tracheal contraction induced by exogenous acetylcholine was also studied.

RESULTS

GABA and GABA agonists and antagonists had no effect on the basal tone of normal guinea-pig tracheae. Both GABAa and GABAb receptor agonists, as well as GABA, suppressed EFS-induced contraction of normal guinea-pig tracheae in a reversible, dose-dependent manner. Moreover, this suppression was reserved to the control level by either GABAa and GABAb receptor antagonists. In tracheal spiral ring prepared from OA-sensitized guinea-pigs, GABA and baclofen caused a smaller reversible inhibition of EFS-induced contraction than in normal tracheal spiral ring, while muscimol inhibited EFS-induced tracheal contraction to a similar extent to that observed in normal tracheae. GABA had no effect on the tracheal contractile response to acetylcholine.

CONCLUSION

The results suggest that there may be a biological mechanism mediated by prejunctional GABAb receptors which attenuates cholinergic contraction of airway smooth muscle and that dysfunction of the receptors may underlie the airway obstruction in asthmatics.

The effect of theophylline on blood and sputum eosinophils and ECP in patients with bronchial asthma

It was recently reported that theophylline has an anti-inflammatory and bronchodilating effect on bronchial asthma. Accordingly, to examine the anti-inflammatory effect of theophylline on asthma, especially its effect on eosinophil activation, a sustained-release theophylline preparation (Theolong) was administered (daily dose: 400 mg) to 18 patients with mild to moderate bronchial asthma. This was done in order to study the preparation's effects on lung function, blood and sputum eosinophils and ECP four weeks pre- and post-administration. Lung function was determined by spirometry and sputum by induced sputum. Blood and sputum ECP levels were determined using an ECP RIA kit. In lung function, there were no differences in vital capacity (VC) or in forced expiratory volume 1 s (FEV 1.0) pre- and post-administration. There were also no differences in the number of blood and sputum eosinophils, but serum and sputum ECP levels decreased. Theophylline is thus expected to exert an inhibitory effect on eosinophil activation and it is suggested as an effective therapeutic drug for bronchial asthma.

Full-matrix least-squares refinement of lysozymes and analysis of anisotropic thermal motion

Crystal structures of turkey egg lysozyme (TEL) and human lysozyme (HL) were refined by full-matrix least-squares method using anisotropic temperature factors. The refinement converged at the conventional R-values of 0.104 (TEL) and 0.115 (HL) for reflections with Fo > 0 to the resolution of 1.12 A and 1.15 A, respectively. The estimated r.m.s. coordinate errors for protein atoms were 0.031 A (TEL) and 0.034 A (HL). The introduction of anisotropic temperature factors markedly reduced the R-value but did not significantly affect the main chain coordinates. The degree of anisotropy of atomic thermal motion has strong positive correlation with the square of distance from the molecular centroid. The ratio of the radial component of thermal ellipsoid to the r.m.s. magnitude of three principal components has negative correlation with the distance from the molecular centroid, suggesting the domination of libration rather than breathing motion. The TLS model was applied to elucidate the characteristics of the rigid-body motion. The TLS tensors were determined by the least-squares fit to observed temperature factors. The profile of the magnitude of reproduced temperature factors by the TLS method well fitted to that of observed B(eqv). However, considerable disagreement was observed in the shape and orientation of thermal ellipsoid for atoms with large temperature factors, indicating the large contribution of local motion. The upper estimate of the external motion, 67% (TEL) and 61% (HL) of B(eqv), was deduced from the plot of the magnitude of TLS tensors determined for main chain atoms which were grouped into shells according to the distance from the center of libration. In the external motion, the translational portion is predominant and the contribution of libration and screw motion is relatively small. The internal motion, estimated by subtracting the upper estimate of the external motion from the observed temperature factor, is very similar between TEL and HL in spite of the difference in 54 of 130 amino acid residues and in crystal packing, being suggested to reflect the intrinsic internal motion of chicken-type lysozymes.

Theophylline suppresses the release of interleukin-4 by peripheral blood mononuclear cells

To elucidate the mechanism of the anti-inflammatory effect of theophylline, peripheral blood mononuclear cells (PBMCs) collected from patients with bronchial asthma who had a RAST score for Dermatophagoides farinae (Df) > = 3 were stimulated with Df antigen, and the interleukin-4 (IL-4) production by the stimulated PBMCs was determined in the presence and absence of theophylline. The stimulated IL-4 production in the PBMCs was significantly suppressed by simultaneous treatment with theophylline (8 microg/ml). Furthermore, the intracellular 3',5'-adenosine monophosphate (cAMP) level following stimulation with Df was significantly higher in PBMCs simultaneously treated with theophylline (8 microg/ml) than in nontreated controls. These results suggest that theophylline suppresses the IL-4 production in inflammatory cells by increasing the intracellular cAMP level; this effect may thus provide an additional basis for the benefit of theophylline in antiasthmatic therapy.

X-ray Structure of Turkey-Egg Lysozyme Complex with Tri-N-acetylchitotriose. Lack of Binding Ability at SubsiteA

The turkey-egg lysozyme (TEL) complex with tri-N-acetylchitotriose [(GlcNac)3] was co-crystallized from 1.5% TEL and 2 mM (GlcNac)3 at pH 4.2. The crystal structure was determined by molecular replacement and refined to an R value of 0.182 using 10-1.77 A data. The (GlcNac)3 molecule occupies the subsites A, B and C. At the subsites B and C, the sugar residues are bound in a similar manner to that found in the hen-egg lysozyme (HEL) complex. In contrast, the GlcNac residue at the subsite A is exposed to bulk solvent and has no contact with the protein molecule because the active residue Asp101 in HEL is replaced by Gly in TEL. A sulfate ion is bound in the vicinity of subsite B and forms hydrogen bonds with the sugar residue and the guanidino group of Arg61, assisting the binding of the sugar residue to subsite B. The active-site cleft of TEL is narrower than that of native TEL, thus attaining the best fit of the (GlcNac)3 molecule. The lack of binding ability of subsite A is discussed in relation to the catalytic properties of TEL. The result suggests that the cleavage pattern of oligosaccharide substrates in the catalytic reaction is regulated by the protein-sugar interaction at subsite A.

Brain metastasis in malignant pleural mesothelioma

A 55-year-old male who had a remote history of occupational asbestos exposure consulted us because of chest pain. Chest X-ray revealed diffuse pleural thickening and pleural effusion on the right. A diagnosis of malignant mesothelioma, biphasic type was made by needle pleural biopsy. Fourteen months later, the patient died of brain metastasis. At autopsy, malignant mesothelioma of the pleura with metastasis to the brain and bilateral adrenal glands was observed. Brain metastases proven by autopsy are rare in cases of malignant mesothelioma. The ferruginous body count in the lung tissue was 16 per gram of wet weight.

Importance of van der Waals contact between Glu 35 and Trp 109 to the catalytic action of human lysozyme

The importance of van der Waals contact between Glu 35 and Trp 109 to the active-site structure and the catalytic properties of human lysozyme (HL) has been investigated by site-directed mutagenesis. The X-ray analysis of mutant HLs revealed that both the replacement of Glu 35 by Asp or Ala, and the replacement of Trp 109 by Phe or Ala resulted in a significant but localized change in the active-site cleft geometry. A prominent movement of the backbone structure was detected in the region of residues 110 to 120 and in the region of residues 100 to 115 for the mutations concerning Glu 35 and Trp 109, respectively. Accompanied by the displacement of the main-chain atoms with a maximal deviation of C alpha atom position ranging from 0.7 A to 1.0 A, the mutant HLs showed a remarkable change in the catalytic properties against Micrococcus luteus cell substrate as compared with native HL. Although the replacement of Glu 35 by Ala completely abolished the lytic activity, HL-Asp 35 mutant retained a weak but a certain lytic activity, showing the possible involvement of the side-chain carboxylate group of Asp 35 in the catalytic action. The kinetic consequence derived from the replacement of Trp 109 by Phe or Ala together with the result of the structural change suggested that the structural detail of the cleft lobe composed of the residues 100 to 115 centered at Ala 108 was responsible for the turnover in the reaction of HL against the bacterial cell wall substrate. The results revealed that the van der Waals contact between Glu 35 and Trp 109 was an essential determinant in the catalytic action of HL.

Origin of carbohydrate recognition specificity of human lysozyme revealed by affinity labeling

In order to reveal the origin of carbohydrate recognition specificity of human lysozyme by clarifying the difference in the binding mode of ligands in the active site, the inactivation of human lysozyme by 2',3'-epoxypropyl beta-glycoside derivatives of the disaccharides, N,N'-diacetylchitobiose [GlcNAc-beta-(1-->4)-GlcNAc] and N-acetyllactosamine [Gal-beta-(1-->4)-GlcNAc], was investigated and the three-dimensional structures of the affinity-labeled enzymes were determined by X-ray crystallography at 1.7 A resolution. Under the conditions comprising 2.0 x 10(-3) M labeling reagent and 1.0 x 10(-5) M human lysozyme at pH 5.4, 37 degrees C, the reaction time required to reduce the lytic activity against Micrococcus luteus cells to 50% of its initial activity was lengthened by 3.7 times through the substitution of the nonreducing end sugar residue, GlcNAc to Gal. The refined structure of human lysozyme labeled by 2',3'-epoxypropyl beta-glycoside derivatives of N,N'-diacetylchitobiose (HL/NAG-NAG-EPO complex) indicated that the interaction mode of the N,N'-diacetylchitobiose moiety in substites B and C in this study was essentially the same as in the case of the complex of human lysozyme with the free ligand. On the other hand, the hydrogen-bonding pattern and the stacking interaction at subsite B were remarkably different between the HL/NAG-NAG-EPO complex and human lysozyme labeled by the 2',3'-epoxypropyl beta-glycoside of N-acetyllactosamine (HL/GAL-NAG-EPO complex). The reduced number of possible hydrogen bonds as well as the less favorable stacking between the side chain of Tyr63 in human lysozyme and the galactose residue in the HL/GAL-NAG-EPO complex reasonably explained the less efficient ability of the 2',3'-epoxypropyl beta-glycoside of N-acetyllactosamine as compared to that of N,N'-diacetylchitobiose as an affinity labeling reagent toward human lysozyme.

Assessment of serum CYFRA 21-1 in lung cancer

BACKGROUND

Cytokeratins are the intermediate filaments of the cytoskeletal protein located in normal epithelia, tumor, and cultured cells. Recently, a fragment of cytokeratin subunit 19, referred to as CYFRA 21-1, detected in the serum of patients with nonsmall cell lung cancer, has been reported as a new tumor marker. This article reports the results of a study of serum fragment CYFRA 21-1, measured by immunoradiometric assay, as a marker of lung cancer.

METHODS

One hundred fourteen patients with primary lung cancer, 6 patients with malignant solid tumor, 116 patients with a variety of benign diseases, and 29 normal individuals were entered into the study. Serum CYFRA 21-1 levels were obtained by means of immunoradiometric assay using the CYFRA 21-1 EIA (enzyme immunoassay) kit. In addition, we studied other tumor markers, including carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCC), and neuron specific enolase (NSE), as a means of lung cancer diagnosis.

RESULTS

The diagnostic accuracy and sensitivity of serum CYFRA 21-1 for the detection of lung cancer were highest among the four markers. The serum CYFRA 21-1 levels were most highly elevated in lung carcinoma patients (in particular UICC Stage IV patients) across different histologic types and attained 85.1% sensitivity when using a threshold of 3.5 ng/mL. The diagnostic sensitivity for detecting lung carcinoma was substantially enhanced by means of combined assays of CYFRA 21-1 with CEA overall for lung cancer, with SCC for squamous cell carcinoma, and with CEA for adenocarcinoma.

CONCLUSIONS

These findings suggest that serum assays of CYFRA 21-1 are clinically useful for the diagnosis of lung carcinoma.

Revascularization in nontraumatic osteonecrosis of the femoral head

To study the revascularization pattern of nontraumatic osteonecrosis, superselective angiography of the femoral medical circumflex artery was done twice on 13 hips for which no treatment had been given. Angiographic evaluation of the hips with early-stage osteonecrosis not visible on radiographs showed the absence of superior retinacular arteries from the stump in all hips. Penetration of small vessels was seen on 6 hips. Bony scintigraphy of 13 hips and magnetic resonance imaging of 9 hips were taken at about the same time. Bony scintigraphy and magnetic resonance imaging results were positive in 11 of 13 hips and in all 9 hips, respectively. The patients were observed until evidence of necrosis appeared on radiographs. When this sign became evident, a second angiography was conducted, which indicated the penetration of erratically formed vessels with increase in size in 12 hips. It was assumed that the blood supply from the superior retinacular arteries was interfered with in large areas of the femoral head and that revascularization started with the formation of small vessels, followed by further penetration of large vessels.

Glioblastoma multiforme in the left frontal lobe subsequent to malignant lymphoma in the right orbit

A 62-year-old male presented with glioblastoma multiforme in the left frontal lobe manifesting as motor aphasia, subsequent to a malignant lymphoma in the right orbit. He underwent subtotal removal of the right orbital mass presenting as right exophthalmos which was shown by histological examination to be non-Hodgkin's lymphoma. He received 30 Gy Lineac irradiation to the right orbit. His post-operative course was satisfactory. Magnetic resonance (MR) imaging with gadolinium-diethylenetriaminepenta-acetic acid (Gd-DTPA) 7 months later demonstrated a small spotty enhanced lesion in the left frontal lobe. He developed motor aphasia 1 year after irradiation. MR imaging disclosed an enhanced mass in the left frontal lobe, which was totally removed. Histological examination revealed glioblastoma multiforme. Patients with malignant lymphoma may develop a subsequent second malignant tumor. MR imaging with Gd-DTPA is quite useful for early detection of a second brain tumor.

Site-directed mutagenesis and sugar-binding properties of the wheat germ agglutinin mutants Tyr73Phe and Phe116Tyr

Wheat germ agglutinin is a dimeric lectin composed of two identical subunits. Each subunit consists of four homologous hevein-like domains of 42 or 43 amino acids each. Amino acid residues at the same position in each domain involved in sugar binding are thought to play a similar role in sugar binding. In order to clarify the role of the amino acid residue at domain position 30 of wheat germ agglutinin isolectin 2 (WGA2) in sugar binding, two WGA2 variants each containing a mutation, either Tyr73-->Phe (domain B) or Phe116-->Tyr (domain C), were produced. The binding activity for (GlcNAc)3 and the three-dimensional structure of these mutants were characterized by comparing with the properties of wild-type WGA2. Equilibrium dialysis experiments using (GlcNAc)3 indicated that the mutation Tyr73-->Phe reduced the overall sugar-binding activity at both pH 5.9 and pH 4.7. In addition, positive cooperativity toward (GlcNAc)3 binding was observed at pH 4.7. In contrast, the mutation of Phe116-->Tyr increased the overall sugar-binding activity at pH 5.9, but reduced this activity at pH 4.7 without changing the number of sugar-binding sites. Positive cooperativity was not observed at pH 5.9 or pH 4.7. X-ray crystallographic analysis of mutant WGA2 revealed that the mutation of Tyr73-->Phe caused a side chain movement of the Glu115 residue of the opposite subunit that formed a hydrogen bond with Tyr73 in wild-type WGA2. No changes were observed in the backbone structure and the disposition of the benzene ring of Phe73. The mutation Phe116-->Tyr caused the formation of a new hydrogen bond between Tyr116 and Glu72 of the opposite subunit. The changes in the sugar-binding properties in WGA2 mutants are discussed in relation to the structural change at the binding site.

X-ray structure of turkey egg lysozyme complex with di-N-acetyl-chitobiose. Recognition and binding of α-anomeric form

The crystalline complex of turkey-egg lysozyme (TEL) with di-N-acetylchitobiose (NAG2) was prepared by a soaking method and the structure was determined by X-ray analysis at 1.55 A resolution. The structure was refined to an R value of 0.175 by simulated annealing and energy minimization. The alpha-anomer of NAG2 is located at subsite D with the orientation perpendicular to the direction of the active-site cleft. The anomeric residue is deeply inserted into the cleft and the O1-H hydroxyl group is hydrogen bonded to the carboxyl group of Glu35 which is a catalytic residue. The other sugar residue protrudes outside the cleft and is in van der Waals contact with the beta-sheet region comprising of residues 43-53. The binding of NAG2 makes the active-site cleft 0.3-0.5 A narrower and suppresses the thermal motion of two lobes constructing the cleft. The NAG2 molecule is bound in a manner not assumed in the catalytic action of the enzyme and the geometry of binding indicates that the alpha-anomer blocks the active center and acts only as an inhibitor.

Alteration of the substrate specificity of human lysozyme by site-specific intermolecular cross-linking

Human lysozyme dimers were prepared by the intermolecular cross-linking of the monomer that contained the mutation of either Arg41 to Cys or Ala73 to Cys with a divalent maleimide compound. Among the three kinds of possible dimers only R41C-R41C dimer, in which the two catalytic clefts can come close to each other due to the proximity of the conjugation site to the active sites, turned out to be 2.3 times more specific to a polymer substrate, ethylene glycol chitin, as compared to an oligomer substrate, PNP-(GlcNAc)5. The result indicates that it is possible to alter the substrate specificity of an enzyme by artificially controlling the orientation of the active sites.

The effect of TYB-2285 on dual phase bronchoconstriction and airway hypersensitivity in guinea-pigs actively sensitized with ovalbumin

The effect of a new anti-asthmatic drug, TYB-2285 (3,5-bis(acetoxyacetylamino)-4-chlorobenzonitrile), was investigated in ovalbumin-sensitized guinea-pigs. When guinea-pigs were pretreated with TYB-2285 (300 mg kg-1, p.o., single dose or consecutively for 7 days), the immediate asthmatic response was inhibited as demonstrated by diminished cyanosis, but not the bronchoconstriction. TYB-2285, given singly or consecutively, inhibited the appearance of late asthmatic response and the infiltration of inflammatory cells, such as eosinophils, into the airway. Additionally, airway hyper-responsiveness was also reversed by the single administration of TYB-2285. Luminol-dependent chemiluminescence of airway-infiltrated cells stimulated with A23187 was inhibited by TYB-2285 in a dose-dependent manner. The present study suggests that TYB-2285 inhibits late asthmatic response and airway hyperresponsiveness by inhibiting the accumulation of eosinophils and other inflammatory cells into the airway, and also by inhibiting the production of oxygen radicals from airway-infiltrated cells.