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Oxidative modification of LDL plays an important role in early atherogenesis but the mechanisms, nonenzymatic and/or enzymatic, by which LDL is oxidized in vivo remain to be established. Several lines of evidence suggest that cellular 15-lipoxygenase (arachidonate 15-oxidoreductase, EC.1.13.11.13) (15-LO) may contribute to oxidative modification of LDL, including recent studies demonstrating that murine fibroblasts overexpressing 15-LO have an enhanced capacity to oxidize LDL in the medium. The present studies were undertaken to better understand the mechanisms by which cells expressing 15-LO bring about oxidative modification of LDL. LDL incubated 1-2 h with the 15-LO-enriched cells showed a much higher lipoperoxide (LOOH) content than did LDL incubated with control cells. By far the largest absolute increase occurred in cholesteryl ester hydroperoxide (CE-OOH), a much lesser increase in free fatty acid hydroperoxides (FFA-OOH), and only a very small increase in phospholipid hydroperoxides (PL-OOH). Addition of EDTA to the medium abolished these increases in LDL lipid hydroperoxides. Enrichment of LDL with probucol or vitamin E also prevented CE-OOH accumulation. Incubation of LDL with linoleic acid hydroperoxide in the absence of cells also caused a significant increase in CE-OOH and this was markedly inhibited by EDTA. These findings provide further evidence for the potential of 15-LO to participate in LDL oxidation by way of a mechanism involving introduction of LOOH into the LDL particle followed by metal-catalyzed propagation.

There is strong experimental evidence that oxidized low density lipoprotein (Ox-LDL) plays an important role in atherosclerosis. However, the mechanisms by which Ox-LDL is formed in vivo are unknown. To test whether 15-lipoxygenase (15-LO) could play a role in oxidation of LDL by cells, we expressed 15-LO activity in murine fibroblasts, which do not normally have 15-LO activity, and tested their ability to modify LDL. Using a retroviral vector, we prepared fibroblasts that expressed 2- to 20-fold more 15-LO activity than control fibroblasts infected with a vector containing beta-galactosidase (lacZ). Compared with LDL incubated with lacZ cells, LDL incubated with 15-LO-containing cells were enriched with lipid hydroperoxides. When these LDL samples were subsequently subjected to oxidative stress, they were more susceptible to further oxidative modification, as judged by increased conjugated diene formation and by increased ability to compete with 125I-Ox-LDL for uptake by macrophages. These findings establish that cellular 15-LO can contribute to oxidative modification of LDL, but the quantitative significance of these findings to the in vivo oxidation of LDL remains to be established.

The cDNA sequence encoding precursor forms of human cathepsin E (CE), an intracellular aspartic proteinase, was expressed in Chinese hamster ovary cells using an SV40 promotor-driven expression vector. By immunoelectron microscopic studies using an anti-human CE antibody and by Percoll density gradient fractionation, the expressed CE was found to be in two different intracellular fractions; the cytosolic compartment and the vacuolar system. The CEs in both the cytosolic and the vacuolar fractions were highly purified by a simple method involving Percoll density gradient fractionation, chromatography on concanavalin A-Sepharose, Mono Q, and TSK-GelG2000SW, and termed s-CE and v-CE, respectively. The v-CE was further separated into a major (v-CE1) and a minor (v-CE2) form by Mono Q chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting revealed that the s-CE and v-CE1 consists of two polypeptides of 90 and 84 kDa, whereas v-CE2 is composed of 84- and 82-kDa polypeptides. The NH2-terminal amino acid sequence analyses showed that the 90- and 84-kDa proteins from both s-CE and v-CE started with Ser3 and Lys30 of the sequence of human gastric CE predicted from its cDNA sequence, respectively, and that the NH2 terminus of the 82-kDa protein of v-CE2 is the Ile37. Upon acid treatment at pH 3.5 and 37 degrees C for 5 min, the 90- and 84-kDa forms are rapidly converted to the 82-kDa form, indicating that the 90-, 84- and 82-kDa proteins are the pro-CE, the intermediate form, and the mature CE, respectively. All the forms of CE are N-glycosylated with high-mannose-type oligosaccharides. The catalytic properties of s-CE and v-CE are comparable to those of natural human CE. These results suggest that the recombinant CE is initially synthesized on membrane-bound ribosomes as a N-glycosylated preproenzyme and that, after cleavage of the signal segment, the 90-kDa proenzyme is proteolytically processed to the intermediate (84 kDa) and mature (82 kDa) forms by the transport system.

Excessive longitudinal segmentation of the radial portion of the limb bud results in the clinical presentation of duplicated and triphalangeal thumbs. These are common congenital problems with various possible associated anomalies and variable inheritance patterns. Reconstruction of a thumb with stable joints, muscle balance, and good alignment requires attention to each tissue component at the time of the initial surgery.

The effects of hemostatic substances on the vascular tone in porcine coronary arteries and the influence of low density lipoprotein on tension were investigated. Thrombin induced a marked concentration-dependent relaxation in prostaglandin F2 alpha-precontracted strips with intact endothelium, whereas it produced a modest constriction in endothelium-denuded arteries. Methylene blue abolished the relaxation, but indomethacin did not affect it significantly. An exposure of the intact strips to low density lipoprotein resulted in a marked inhibition of the relaxation to thrombin but did not interfere with vasodilation by sodium nitroprusside. The inhibition by low density lipoprotein was reversed completely by washing. In contrast, high density lipoprotein lacked such inhibitory effects. Adenosine diphosphate, calcium ionophore A23187, and platelet-activating factor also produced relaxation in the intact strips. An exposure of the strips to low density lipoprotein almost abolished relaxation to these substances. The inhibition was also reversible. Heat treatment or acid treatment of low density lipoprotein resulted in a complete loss of the inhibitory effects, but diisopropyl fluorophosphate treatment did not alter the effect. It is concluded that low density lipoprotein may play a new pathological role in promotion of coronary vasospasm through rapid and reversible inhibition in endothelium-dependent relaxation to hemostatic substances.

Self-assembled InAs quantum dot (QD) lasers emitting at 1.29 mum on GaAs substrates grown by metalorganic chemical vapor deposition (MOCVD) were achieved by using GaInNAs embedding layers. This emission wavelength is the longest wavelength ever reported for QD lasers grown by MOCVD

E-beam mask writer is an extremely important tool to fabricate the x-ray mask. E-beam writing process is required to have enough placement accuracy and CD controllability for 1X mask. A variable-shaped 100 kV e-beam mask writer EB-X3 has been developed for x-ray membrane mask fabrication and evaluated by using commercially available positive tone resists. We have shown that the high resolution of 50 nm L/S could be obtained for ZEP-520 resists by using the stable 100 kV EB writer. In this study we focus on the chemically amplified (CA) resists for x-ray membrane mask fabrication.

A variable-shaped electron beam (e-beam) mask writer, EB-X3 was developed for 100 nm node 1/spl times/X-ray mask fabrication. It features a stable electron column of 100 kV and the address unit of 1 nm. This paper describes delineation characteristics of the EB-X3 on X-ray membrane mask. We have evaluated image placement (IP) accuracy and e-beam proximity effects on the X-ray membrane delineated with the EB-X3. In order to achieve highly precise IP and CD accuracy, we evaluated beam drift, temperature control, mask blanks support method, resist process, and proximity effect. Precise temperature control and a three-point support pallet are keys for excellent IP. Good CD control less than 10 nm was obtained with low proximity effects with ZEP resist and normal-hexyl acetate developer. The EB-X3 was used for X-ray mask fabrication in conjunction with an X-ray stepper in exposure experiments.

A resurgence of interest in Madelung's deformity has developed recently because of improved operations for correction of the deformity, identification of the genetic loci for the condition in certain syndromal variants, identification of an anterior ligamentous structure tethering the carpus, and preventive treatments in growing children. The process is reviewed in this article and a new surgical technique is presented. The procedure is performed by way of an anterior incision that is more cosmetically appealing. The release of an anterior ligamentous structure described by Vickers is performed simultaneously with a dome shaped osteotomy of the radius. The fragments, once alignment is corrected, are stablized with temporary pin fixation and a long arm cast until the bone has healed.

The solid-state laser crytsal with waveguide structure has several advantages over bulk one due to the optical confinement which leads to the low-threshold and efficient oscillation. Among various solid-state laser media, neodymium doped yttrium aluminum garnet (Nd: YAG) waveguide has strong potential for application to diode-pumped waveguide lasers1,2) and is also an ideal candidate for integrated optoelectronics applications such as Q-switched microchip lasers3,4) which can be realized by monolithically combining their waveguide lasers with other optical components (e. g. Cr YAG thin film) on the same substrate. Thus, the possibility of fabricating YAG thin films with waveguide structure on various substrates will widen their applications in the fields of integrated optics.

A five-year-old boy is presented with multiple finger and toe amputations, secondary to meningococcemia. The child developed a bimanual use pattern of the upper extremities with a significant amount of soft tissue scarring. The left hand was reconstructed according to Ilizarov's method by a combination of distraction lengthening of the metacarpals with two mini-Hoffman distractors and gradual interdigital space widening with web deepening accompanied by a modified Ilizarov apparatus. One year after removal of the external fixation frame, the web space is preserved and the child is adapting to the pincer-like function of his hands.

Production of biphenomycin A by Streptomyces griseorubiginosus 43708 was stimulated by a mixed culture with a partner strain, Pseudomonas maltophilia 1928. This stimulatory effect on biphenomycin A accumulation by the mixed culture was caused by the enzyme activity which strain 1928 possessed. It is suggested that in a mixed culture strain 43708 produces a precursor of biphenomycin A in culture broth and that strain 1928 converts the precursor to biphenomycin A.

Parmi les sequelles des paralysies obstetricales du plexus brachial, la subluxation ou luxation posterieure, ainsi que la dysplasie scapulohume-rale, sont frequemment identifies chez l’enfant en cours de croissance. L’enraidissement articulaire y etant associe en justifie le depistage et la prevention. De rares publications recentes evoquent la survenue de cette complication avant l’âge de un an, mais sa prevalence n’a pas ete rapportee dans la jeune enfance. Materiel et methode 134 nourrissons porteurs de paralysie obstetricale du plexus brachial ont ete examines consecutivement, sur une periode de deux ans. au Texas Scottish Rite Hospital de Dallas. La perte rapide de rotation externe, en depit du programme de reeducation, une asymetrie des plis cutanes, une inegalite apparente de longueur du segment humeral, ainsi que la perception palpatoire de la tete humerale luxee en arriere de la glenoide, ont conduit a la realisation d’une echographie de l’articulation scapulohumerale. Douze cas de luxation posterieure ont ainsi ete identifies avant l’âge de un an, representation une incidence de 9 %. L’âge moyen de survenue est de six mois, de 3 a 10 mois. La perte de rotation externe est brutale, 65 degres en moins de deux mois. Conclusion L’incidence elevee de luxation posterieure, contrastant avec la rarete de sa description avant l’âge de un an, suggere la difficulte de son diagnostic. La precocite de sa survenue indique la necessite une recherche attentive et d’un traitement precoce afin d’en eviter de severes deformations articulaires secondaires. Le but de ce papier est de decrire les signes cliniques evocateurs et d’encourager la prescription d’une echographie de l’epaule en cas de suspicion de luxation posterieure.

Clinical evaluation of the locomotor system has long been hampered by difficulty in assessing the morphologic and functional integrity of skeletal muscles. Diagnostic imaging represents a major advance in the diagnosis and management of patients with locomotor dysfunction through the possibility of probing beyond overlying soft tissues to identify muscle lesions, determine their extent, characterize their composition, direct invasive procedures, and monitor therapies. Magnetic resonance imaging (MRI) appears to be the most promising of available imaging methods, because of its great sensitivity to changes in muscle water distribution and fat content. Also, it can distinguish between individual deep and superficial muscles. Serial evaluations of many muscles are practical because of the safety of MRI. While the cost effectiveness in the workup of locomotor dysfunction remains to be determined, the scientific and practical clinical information now available merits further investigation by clinicians and radiologists alike. The purpose of this review is to describe the potential role of skeletal muscle MRI in evaluating the locomotor system.

Two cases of Larsen's syndrome, that we have recently experienced, were reported.Case I, a male, aged 10 years, was born via an uncomplicated delivery.Case II, a female, aged 6 years.They had prominent forehead and wide spaced eye.They had bilateral hip, knee and elbow dislocations. In addition, they had foot deformity.Radiographic studies showed abnormalities.They had extra calcaneal ossification, short metacarpals, supernumerary carpal bones and anormalous segmentation of vertebrae.

In treating cervical spondylosis, we first, chose concervative therapy such as head halter traction, cervical brace and medication.In 14 cases not improved by these conservative metods we, after determining the exact level of the spondylosis, performed the operation of “anterior cervical fusion”.One of the most important factors in performing anterior cervical fusion is to decide the correct level of the spondylosis as this procedure affects the success of the operation.It is relatively easy to decide the level if the plain-X ray shows the degeneration in only one vertebra. However, if it reveals degenerative findings in more than one, it becomes necessaary to perform further investigations such as Musle Testig, EMG, Myelography, and Discography, during operation, in addtion to the clinical neurogical examinations. We did not perform fusion of more than two intervertebral spaces.

We report the four cases of the spinal cord tumor which we have experienced recently.Case 1. female … aged fifty was a neurinoma occured in the canda equina.Case 2. female … aged thiry five was a epidermal cyst occured in the nineth thoracic vertebral region.Case 3. male … aged fifty seven intramedullary astrocytoma which occured in the region of the fourth thoracic vertebrae.Case 4. female … aged eighteen was a meningioma occured in the extradural space of the fourth and fifth thoracic vertebrae.In the case 1. 2. 4. tumors were operatively almost completely resected, but in the case 3. unable to resect. Consequently in the former, symptom (sensory and motor disturbance) has obviously improved and deminished, but in the latter not improved and deteriorated.

Primary hyperparathyroydism in childhood is a rare occurence.The present report is of a 13-year-old girl who explained of pain and varus deformity of the hip joint for 2 years.On the laboratory examinations, hypercalcemia, hypophosphatemia, hypercalciuria, hyperposphaturia and increased serum alkaline phosphatase were found.Parathyroid gland function tests were of its hyperfunction.On the radiographic examination of long bones, skull and fingers, diffuse resorption and cystic areas wewe seen. A small tumor was found at the right lower pole of the thyroid.A diagnosis of primary hyperparathyroidism was made and surgical exstirpation was performed. The histological diagnosis was a chief cell adenoma of parathyroid gland.After exstirpation, serum calcium and phosphorous concentration gradually become within normal limmits and hip pain was diminished. Lately we performed valgus osteotomy of the Femur, for its varus deformity.

Traumatic disruption of the acetabular triradiate physeal cartilage is an infrequent injury. When it occurs during adolescence, subsequent growth changes in acetabular morphology and congruency of the hip joint are unlikely. However, in younger children, especially those who are less than ten years old, acetabular growth abnormality is a frequent complication of this injury and may result in a shallow acetabulum similar to that seen in patients with congenital disease of the hip. By the time of skeletal maturity, disparate growth increases the incongruency of the hip joint and may lead to progressively more severe subluxation of the hip. Acetabular reconstruction may be necessary to correct the gradual subluxation of the femoral head. Variable irregularities of growth at the proximal end of the femur also may occur. In this series, nine patients with triradiate physeal-cartilage injury were classified according to the degree of displacement and the probable type of growth-plate disruption. Two main patterns of injury occurred. The first was a shearing type-1 or 2 growth-mechanism injury, with central displacement of the distal portion of the acetabulum. This injury pattern seems to have a favorable prognosis for continued normal acetabular growth, although premature closure of the triradiate physes may occur. The other pattern appeared to be a crushing type-5 growth-mechanism injury. This type has a poor prognosis, with premature closure of the triradiate physes occurring secondary to the formation of a medial osseous bridge. In either pattern, the prognosis is dependent on the age of the patient at the time of injury and on the extent of chondro-osseous disruption.

Recently, there has been an increasing interest in the diagnostic and prognostic usefulness of tumor-associated antigen of embryonic and fetal origin. Many approaches have been attempted to make an early diagnosis of the pancreatic cancer, where a specific screening blood test for the pancreatic cancer is required. By using antiserum to fetal pancreas, Banwo et al, discovered an oncofetal antigen that was present in human fetal pancreas, pancreatic tumor tissue, and sera from patients with the pancreatic cancer. Pancreatic oncofetal antigen (POA) was considered to be an oncofetal antigen for human pancreas, and its measurement seemed to be useful in the diagnosis of pancreatic cancer. But elevated levels of POA were also observed in the serum of some patients with cancer of the stomach, lung, colon, or liver as well as in the serum of some pregnant women and others with certain benign conditions. In summary, combined assay with various tumor markers was considered to be useful for the diagnosis of pancreatic cancer.

MCNU is a new derivative of nitrosourea and experimental studies have shown equal or superior activity to known nitrosourea compounds. Twenty one cases were entered into our clinical studies with a phase II study. Nineteen cases have had a several courses of prior chemotherapy. Four out of 21 cases achieved a partial response (each one of lymphoepithelioma, parotid gland cancer, recurrent uterine cancer and recurrent breast cancer). The major toxicity encountered during treatment was myelosuppression. Full recovery of myelosuppression was delayed and was seen six to eight weeks after each injections. These initial results justify further clinical investigations with MCNU.