Search PubMed⌕ Search

Biomedical subjects

A Nagano

Publications and source records attributed to A Nagano.

At least 55 records · Page 3Linked to original sources
PubMed1998

Different modes of cell death induced by 5-fluoro-2'-deoxyuridine in two clones of the mouse mammary tumor FM3A cell line.

The mode of cell death induced by 1 microM 5-fluoro-2'-deoxyuridine (FdUrd) changed in a wild-type F28-7 clone of mouse mammary tumor FM3A cells after a six-month culture. In the original stocked F28-7 clone, FdUrd-induced cell death was accompanied by necrosis-like cell swelling and DNA fragmentation to 100-200 kbp. In subclone F28-7-A isolated from F28-7 cells, which had been cultured for six months, apoptotic bodies and nucleosomal DNA-ladder fragments were observed with the treatment. Furthermore, we investigated the differences in FdUrd-induced intracellular signals between these clones. In F28-7 cells, FdUrd induced increases in caspase-3-like activity, and the mRNA levels of the c-jun, c-fos and c-myc genes, which were greater and earlier than those in F28-7-A cells. Moreover, intracellular acidification occurred in F28-7-A cells treated with FdUrd, though it was not observed in F28-7 cells. These findings suggest that FdUrd-induced cell death occurred through the death program to cell lysis (necrosis) without apoptosis when the induction of these intracellular signals was very high and when intracellular acidification was deficient. Investigation of the differences in the mode of FdUrd-induced cell death between these clones would be important for elucidating the molecular mechanism of pivotal events guiding cells toward either apoptosis or necrosis.

Animals↗
PubMed1998

Development of synchronous bilateral lung cancers after esophagectomy for esophageal cancer: report of a case.

It is well known that squamous cell carcinoma of the esophagus can be associated with carcinoma of other organs. We report herein the rare case of a 60-year-old man who developed synchronous bilateral lung cancers after undergoing esophagectomy for esophageal cancer. Staged bilateral lobectomy was successfully performed to minimize respiratory complications 3 years after his esophagectomy. This case report serves to demonstrate that aggressive and careful surgical approach with adequate followup offers the chance of long-term survival for patients with multiple primary cancers.

Adenocarcinoma↗
PubMed1998

Treatment of brachial plexus injury.

A brachial plexus injury is the most severe nerve injury of the extremities. To achieve good results from treatment, correct diagnosis and early nerve repair are mandatory. The brachial plexus should be explored as early as possible if there is an incised wound, if clinical findings or diagnostic imaging indicate that at least one root is avulsed, if there is damage to the subclavian artery, and if there is total-type injury. With an upper-type injury with no clinical signs of a preganglionic lesion, the patient should be treated conservatively for 3 months and if there are no signs of recovery, then the brachial plexus should be explored. During this exploration, recording of the spinal cord evoked potential (ESCP) or the somatosensory evoked potential (SEP) is mandatory to determine the site of injury. Nerve grafting is indicated for a rupture in the root demonstrating a positive ESCP or SEP potential, in the trunk or in the cord. Exploration of the brachial plexus should be extended distally as far as possible to achieve good results after nerve grafting; when this was done more than M3 (MRC grading) power of the infraspinatus, deltoid, and biceps was achieved in more than 70% of our 32, 30, 33 patients, respectively. Results of nerve grafting for the forearm muscles have been very poor. Intercostal nerve transfer is recommended to restore elbow flexion in root avulsion type of injury, with elbow flexion to more than M3 being regained in 70% of our 221 patients. The best results of intercostal nerve transfer were achieved in patients younger than 30 years who received the operation within 6 months after injury. Motor recovery of hand function after intercostal nerve transfer was poor but protective sensation was restored in fingers innervated by the median nerve. The recommended treatment for each type of injury is described according to the results achieved.

Brachial Plexus↗
PubMed1998

Comparison of new approaches to estimate mechanical output of individual joints in vertical jumps.

Conventional calculation of joint power is not effective in order to assess translational motions of human body. Two new approaches were developed in this study to estimate translational mechanical outputs from individual joints. They were applied to the analysis of vertical jump motions of six male subjects. In both cases, body of subjects were modeled with a four mass-points system model, and joints were regarded as motion generators. In one approach, increase of vertical component of ground reaction force (GRF) was decomposed into push-off force of three joints (ankle, knee, and hip joints). This procedure gave an estimation of impulse exerted per leg, as 83-92 N s (95% confidential interval) for squat jump, which was similar to half of the impulse provided to mass center of the body calculated from GRF, 82-88 N s. In the other approach, amount of the power exerted by each joint vertically was estimated by calculating the scalar product of joint reaction force and relative velocity vectors of adjacent segments. This approach gave estimation of vertical work provision per leg, as 201-226 and 141-181 J for squat and counter movement jumps, which were not so different from half of the work provided to mass center of the body calculated from GRF, 209-227 and 137-175 J, respectively. As these approaches make it possible to calculate translational mechanical outputs specifically, they are useful and consistent concerning the analysis of translational motion of human body.

Ankle Joint↗
PubMed1998

In vitro sorption and desorption of basic fibroblast growth factor from biodegradable hydrogels.

In vitro interaction of basic fibroblast growth factor (bFGF) with biodegradable gelatin hydrogels was investigated, focusing on its sorption into the hydrogels and desorption from them. Basic bFGF was sorbed to the hydrogel of acidic gelatin with an isoelectric point (IEP) of 5.0 over time at 4 degrees C, in contrast to that of basic gelatin with an IEP of 9.0 and type I collagen. The bFGF sorption was almost independent of the sorption temperature except for 4 degrees C and the hydrogel water content. Fluorescent microscopic observation revealed that bFGF was sorbed into the interior of the acidic gelatin hydrogel. The binding molar ratio of bFGF to the acidic gelatin was around 1.0. The bFGF sorption to the acidic gelatin hydrogel increased when gelatin was further carboxylated. bFGF was sorbed into the acidic gelatin hydrogel more slowly than into the poly(acrylic acid) (PAAc) hydrogel, probably because of the lower density of negative charge of gelatin. The bFGF sorption decreased with an increase in solution ionic strength, indicating that an electrostatic interaction was the main driving force for bFGF sorption to the acidic gelatin hydrogel. However, even at higher ionic strengths of solution, the sorbed bFGF was not desorbed from the acidic gelatin hydrogel, in contrast to the PAAc hydrogel.

Acrylic Resins↗
PubMed1998

Avulsion injury of cervical nerve roots: enhanced intradural nerve roots at MR imaging.

PURPOSE: To study the magnetic resonance (MR) imaging features of intradural nerve roots in avulsion injury of the cervical nerve roots. MATERIALS AND METHODS: Presurgical gadolinium-enhanced MR imaging was performed in 27 consecutive patients. The images were evaluated for enhancement of the intradural nerve roots and enhancement of the spinal cord surface at the root entry zone ("root stump" enhancement) by two radiologists, who were blinded to the clinical information. Intradural nerve roots were classified as enhanced, normal, or not visible. Root stumps were classified as enhanced or normal. The results were compared with the results of nerve root continuity studies (exploratory surgery with intraoperative recording of somatosensory evoked potentials or neurologic examination). RESULTS: At the 250 nerve levels (500 nerve roots) studied, 12 enhanced nerve roots and 42 enhanced root stumps were found. Seven enhanced nerve roots and 38 enhanced root stumps were related to preganglionic injury. Results of the kappa test for interobserver concordance on findings of intradural nerve roots and root stumps were 0.55 and 0.93, respectively. CONCLUSION: Although visualization of nerve roots is a problem, enhanced MR imaging is a noninvasive means of obtaining anatomic information and unique physiologic information on injured intradural nerve roots.

Adolescent↗
PubMed1997

Dyggve-Melchior-Clausen syndrome without mental retardation (Smith-McCort dysplasia): morphological findings in the growth plate of the iliac crest.

Dyggve-Melchior-Clausen syndrome without mental retardation (Smith-McCort dysplasia) (SM) has clinical and radiographic findings similar to those of Dyggve-Melchior-Clausen syndrome (DMC) except for mental retardation. Iliac crest biopsies from two patients with SM were examined. The lace-like appearance of the iliac crests, which is a characteristic radiological sign of SM and DMC, was caused by bone tissue deposited in a wavy pattern at the osteochondral junction. The growth plate showed abnormal enchondral ossification with no columnarization of chondrocytes. Electron microscopy demonstrated chondrocytes with dilated cisternae of rough endoplasmic reticulum containing fine granular or amorphous material, similar to those reported in cases of DMC. Thus, SM has pathologic changes in common with DMC as a rough endoplasmic reticulum storage disorder, even though the mental condition is different.

Cartilage↗
PubMed1997

Mutations in the N-terminal globular domain of the type X collagen gene (COL10A1) in patients with Schmid metaphyseal chondrodysplasia.

Schmid metaphyseal chondrodysplasia (SMCD) is a relatively common, heritable osteochondrodysplasia characterized by short-limbed short stature with normal facies, and generalized metaphyseal dysplasias of the long and short tubular bones. Several mutations of the type X collagen gene (COL10A1) have been reported in patients with SMCD, all in the C-terminal globular domain. To address whether mutations in other domains can cause SMCD, we examined the coding region of the COL10A1 gene in DNA samples from six Japanese families affected with SMCD, by direct sequencing. We detected novel mutations in three unrelated SMCD patients; one was a one-base deletion in the C-terminal globular domain and others were de novo missense mutations in the N-terminal globular domain. All three cases revealed a typical clinical phenotype for SMCD. Thus, we have demonstrated that mutations of COL10A1 in regions other than the C-terminal globular domain can cause SMCD, and the results suggest that the N-terminal globular domain also plays an important role in formation of type X collagen.

Asian People↗
PubMed1997

Familial occurrence of hyperplastic callus in osteogenesis imperfecta.

There is a hypothesis that hyperplastic callus (HC) in osteogenesis imperfecta (OI) is not merely a rare complication but could actually be inherited, although this idea has not yet been investigated. We described two cases, a mother and son, with mild OI, normal scleral colour and no dentinogenesis imperfecta, who repeatedly had HC in their femur. Familial occurrence of HC was found in 13 cases in 5 families among 21 cases in 7 families with a familial background of OI in the literature (including this report). This is higher than the reported incidence of HC, 1.5% (5 cases of 333), and the mode of transmission is concomitant with autosomal dominant inheritance in all these families. Since a review of 47 cases in the literature shows that HC occurs independently of scleral colour and the degree of bone fragility, it may be an additional criterion for subdivision within each type of the Sillence classification.

Adult↗
PubMed1997

Arc osteotomy of the humerus to correct cubitus varus.

The appearance of the elbow after corrective osteotomy for cubitus varus often is different from that of the unaffected side, even if the carrying angle of the affected side is corrected to match that of the unaffected side. Not only must the carrying angle formed by the humerus and the ulna be corrected, but the lateral shift between the humeral axis and the ulnar axis also should be corrected to achieve a matching appearance after corrective osteotomy. Based on this concept, a technique of arc osteotomy was developed to correct simultaneously both the angle and the lateral shift of the affected elbow joint to match those of the unaffected side. This new method has been used to treat 12 patients. The length of followup averaged 28 months, with a range of 8 to 70 months. The carrying angle was corrected from 22 degrees varus on average to 6 degrees valgus on average, with a difference between the right and left side of 2 degrees on average. No complication was observed during the treatment. The average range of motion of the elbow joint was from 0 degrees extension to 125 degrees flexion preoperatively and from 6 degrees hyperextension to 134 degrees flexion postoperatively.

Adolescent↗
PubMed1997

Results of nerve grafting for injuries of the axillary and suprascapular nerves.

We report the results in 33 patients who had nerve grafting of the axillary or the suprascapular nerve or of both. There were 32 men and one woman; their mean age was 21 years and the average interval between injury and operation was three months. At a mean follow-up of 27 months, the deltoid had recovered to M3 or better in 23 of 30 patients (77%) and the infraspinatus in 18 of 25 patients (72%). Shoulder elevation had reached 120 degrees or more in 27 patients (82%), with external rotation of 30 degrees or more in 27 (82%). Twenty-six patients (79%) could reach to the top of their head with their hand. Recovery of muscle strength, range of movement and shoulder function were satisfactory when surgery was performed within four months of the injury. Early exploration and nerve grafting can lead to a good functional recovery, but thorough exploration and careful repair of both nerves are essential.

Adolescent↗
PubMed1997

Full exposure of the axillary and suprascapular nerves.

We describe a method of exposing the whole length of the axillary and suprascapular nerves through a sabre-cut incision. The coracoid process is osteotomised and part of trapezius is detached from its insertions. The posterior deltoid is freed from its scapular origin to expose infraspinatus. We have used this approach to explore combined injuries of the axillary and suprascapular nerves with good results, and no serious complications. Its success depends on a meticulous surgical technique.

Axilla↗
PubMed1997

[A case of postbulbar duodenal ulcer due to adjuvant chemotherapy after gastrectomy for gastric cancer].

We encountered a rare case of postbulbar ulcer caused by adjuvant chemotherapy after gastrectomy. A 64 year-old woman, who received chemotherapy with CDDP-5-FU after gastrectomy, developed severe hematemesis. Endoscopic examination revealed a gigantic ulcer at the anal site of Vater's papilla. The ulcer was healed with PPI and soft diet.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1997

The molecular mechanisms of 5-fluoro-2'-deoxyuridine induced cell death.

The molecular mechanism of cell death induced by 5-Fluoro-2'-deoxyuridine (FUdR) was investigated. FUdR caused cell death to induce dNTP pool imbalance and following DNA double strand breaks in mouse mammary tumor FM3A cells. We isolated a new endonuclease from FUdR-treated cells, named endonuclease S, that played an important role in FUdR-induced cell death. Cells treated with FUdR showed intracellular acidification before cell death formation. We observed that the endonuclease S in acidic cells may lead the DNA fragmentation. On the other hand, we observed that protease inhibitors (such as TLCK, TPCK, PMSF, p-APMSF, Pefabloc SC and Z-Asp-CH2-DCB) blocked intracellular acidification, DNA fragmentation and FUdR-induced cell death. But the inhibitors did not affect dNTP pool imbalance in the cells. These results suggest that proteases act at the point of downstream of dNTP pool imbalance and upstream of the intracellular acidification.

Animals↗
PubMed1996

Spontaneous anterior interosseous nerve palsy with hourglass-like fascicular constriction within the main trunk of the median nerve.

Interfascicular neurolysis was performed in nine patients with spontaneous anterior interosseous nerve palsy. In eight of these patients, an hourglass-like constriction in the fascicles forming the anterior interosseous nerve was found within the main trunk of the median nerve at 2-7.5 cm above the medial epicondyle. The clinical signs and symptoms of these eight patients were similar to those that have been described to isolated neuritis. While the etiology remains unknown, when spontaneous anterior interosseous nerve palsy is suspected to be caused by isolated neuritis, interfascicular neurolysis should be performed to confirm the lesion and to discover whether fascicular constriction is present.

Adult↗
PubMed1996

Emerin deficiency at the nuclear membrane in patients with Emery-Dreifuss muscular dystrophy.

Mutations in the STA gene at the Xq28 locus have been found in patients with X-linked Emery-Dreifuss muscular dystrophy (EDMD). This gene encodes a hitherto unknown protein named 'emerin'. To elucidate the subcellular localization of emerin, we raised two antisera against synthetic peptide fragments predicted from emerin cDNA. Using both antisera, we found positive nuclear membrane staining in skeletal, cardiac and smooth muscles in the normal controls and in patients with neuromuscular diseases other than EDMD. In contrast, a deficiency in immunofluorescent staining of skeletal and cardiac muscle from EDMD patients was observed. A 34 kD protein is immunoreactive with the antisera--the protein is equivalent to that predicted for emerin. Together, our findings suggest the specific deficiency of emerin in the nuclear membrane of muscle cells in patients with EDMD.

Adolescent↗
PubMed1996

Nerve grafting in brachial plexus injuries. Results of free grafts in 90 patients.

We have assessed the efficacy of free nerve grafts in 90 cases of brachial plexus injury. Relatively good recovery of the elbow flexor and extensor muscles and of those of the shoulder girdle was found but recovery of the flexors and extensors of the forearm and of the intrinsic muscles of the hand was extremely poor. Poor results were found when spinal nerve roots seemed normal to the touch and appeared intact but had abnormal somatosensory evoked potentials or myelography. Recovery of the deltoid and infraspinatus muscles was better when injury had occurred to the circumflex and suprascapular nerves rather than to the plexus itself, perhaps because these nerves were explored in their entirety to determine the presence of multiple lesions. It is important to visualise the entire nerve thoroughly to assess the overall condition. Thorough exploration of the plexus and the use of intraoperative recording of somatosensory evoked potentials are essential.

Adolescent↗