Visualization of an FtsZ ring in chloroplasts of Lilium longiflorum leaves

FtsZ is a bacterial division protein which forms a ring at the leading edge of the cell division site. To date, a hypothesis that the plant FtsZ forms the same structure in chloroplast division is proposed, but has not been demonstrated yet. In this study, recombinant LlFtsZ (Lilium longiflorum FtsZ) protein was produced from a previously isolated ftsZ cDNA clone [Mori and Tanaka (2000) Protoplasma 214: 57] and used to raise polyclonal anti-LlFtsZ antibodies in rabbits. In immunoblot analysis with the total protein extracted from L. longiflorum leaves, purified antibodies specifically recognized LlFtsZ whose molecular mass was approximately 43 kDa. This size corresponded to that of the recombinant LlFtsZ protein lacking N-terminal sequence, which suggests that the full-length LlFtsZ translation product has a putative N-terminal signal peptide. Moreover, fluorescent and electron microscopy revealed that the anti-LlFtsZ antibodies recognized ring structures at stromal side of the constriction point of dividing chloroplasts. Here, we show direct evidence that FtsZ ring is involved in chloroplast division.

Novel filaments 5 nm in diameter constitute the cytosolic ring of the plastid division apparatus

The plastid division apparatus (called the plastid-dividing ring) has been detected in several plant and algal species at the constricted region of plastids by transmission electron microscopy. The apparatus is composed of two or three rings: an outer ring in the cytosol, an inner ring in the stroma, and a middle ring in the intermembrane space. The components of these rings are not clear. FtsZ, which forms the bacterial cytokinetic ring, has been proposed as a component of both the inner and outer rings. Here, we present the ultrastructure of the outer ring at high resolution. To visualize the outer ring by negative staining, we isolated dividing chloroplasts from a synchronized culture of a red alga, Cyanidioschyzon merolae, and lysed them with nonionic detergent Nonidet P-40. Nonidet P-40 extracted primarily stroma, thylakoids, and the inner and middle rings, leaving the envelope and outer ring largely intact. Negative staining revealed that the outer ring consists of a bundle of 5-nm filaments in which globular proteins are spaced 4.8 nm apart. Immunoblotting using an FtsZ-specific antibody failed to show immunoreactivity in the fraction containing the filament. Moreover, the filament structure and properties are unlike those of known cytoskeletal filaments. The bundle of filaments forms a very rigid structure and does not disassemble in 2 M urea. We also identified a dividing phase-specific 56-kD protein of chloroplasts as a candidate component of the ring. Our results suggest that the main architecture of the outer ring did not descend from cyanobacteria during the course of endosymbiosis but was added by the host cell early in plant evolution.

A putative mitochondrial ftsZ gene is present in the unicellular primitive red alga Cyanidioschyzon merolae

Two ftsZ homologues were isolated from the unicellular primitive red alga Cyanidioschyzon merolae (CmftsZ1 and CmftsZ2). Phylogenetic analysis revealed that CmftsZ1 is most closely related to the ftsZ genes of alpha-Proteobacteria, suggesting that it is a mitochondrial-type ftsZ gene, whereas CmftsZ2 is most closely related to the ftsZ genes of cyanobacteria, suggesting that it is a plastid-type ftsZ gene. Southern analysis indicates that CmftsZ1 and CmftsZ2 are both single-copy genes located on chromosome XIV in the C. merolae genome. Northern analysis revealed that both CmftsZ1 and CmftsZ2 are transcribed, and accumulate specifically before cell and organelle division. The results of Western analysis suggest that CmFtsZ1 is localized in mitochondria.

Chondro-osseous differentiation in fat tissue tumors: magnetic resonance imaging with pathological correlation

Chondro-osseous differentiation of three benign or malignant fat tissue tumors--two chondrolipomas and a liposarcoma with cartilaginous metaplasia--was studied with magnetic resonance (MR) imaging and compared with their pathological findings. The results suggest that demarcation of cartilage tissue can be clearly defined on MR imaging when the size of the cartilaginous area is large. Myxoid matrix, degenerative fat tissue and lipodystrophic change may decrease the delineation of the cartilage tissue.

Natural progression of osteochondritis dissecans of the humeral capitellum: initial observations

PURPOSE

To determine the earliest findings, subsequent changes, and natural course of osteochondritis dissecans of the humeral capitellum.

MATERIALS AND METHODS

Among 95 patients with osteochondritis dissecans of the humeral capitellum, 16 (mean age, 12.5 years) were selected for this retrospective study because they seemed to have early osteochondritis dissecans and had been followed up without any surgical treatment for 6 months or more (mean, 3.5 years).

RESULTS

The initial imaging appearances of the 16 patients' lesions were divided into two types: localized subchondral bone flattening without fragments in seven, and nondisplaced fragments in nine. Patients with lesion flattening had younger ages and significantly shorter durations of symptoms, and most had open growth plates. In five of the seven with flattening, new bone formed over the flattened bone, and the fragments united after arm motion reduction. In contrast, patients with nondisplaced fragments at clinical presentation had longer durations of symptoms with continued arm motion, and their nondisplaced fragments failed to unite.

CONCLUSION

The earliest feature of osteochondritis dissecans is subchondral bone flattening, over which new bone subsequently forms. The new bone then can unite with the underlying bone. However, if subjected to repetitive forces over a given time, unstable fragments develop. These fragments, even if not yet displaced, are unable to unite.

[A clinical study on pulmonary tuberculosis in younger age groups]

In 1997, the number of newly registered patients with pulmonary tuberculosis increased, compared with that in 1996, in Japan. The majority of the increase were occupied by elder patients 70 years of age or higher. But in younger group less than 30 years old, a reduction in the incidence of tuberculosis had been slowed down, until 1996. The purpose of this report is to elucidate the characteristics of these younger patients. 139 cases younger than 30 years of age, who were hospitalized in the tuberculous ward of IMCJ from April 1995 to March 1998, were investigated, and were compared with the control group (557 cases), 30-79 years old who were hospitalized during the same period. In the younger group, the proportion of women cases, discovered by health examination, foreigners, and contact with TB patients in the past was significantly higher than in the control group. But there were no difference between the both groups, concerning the proportion of those spending irregular life or living alone. The proportion of sputa smear negative cases was significantly higher in the younger group than in the control. For early diagnosis of TB among younger group, the application of bronchofiberscopy and nucleic acid diagnostic method, are encouraged.

Isolation, characterization, and chromosomal mapping of an ftsZ gene from the unicellular primitive red alga Cyanidium caldarium RK-1

The FtsZ protein is involved in eukaryote plastid division, but there is little information on its involvement in the plastid-dividing apparatus. To investigate the relationship between FtsZ and the plastid-dividing ring, the ftsZ gene was isolated from the unicellular primitive red alga Cyanidium caldarium RK-1. Comparison of several prokaryotic and eukaryotic FtsZ proteins shows that there are six highly conserved domains in the core region of FtsZ. To determine the chromosomal location of ftsZ, we first determined the electrophoretic karyotype of C. caldarium RK-1. Southern-hybridization analysis combined with CHEF revealed the chromosomes on which the ftsZ gene exist. Northern-hybridization analysis indicated that the C. caldarium RK-1 ftsZ gene is transcribed as a 1.9-kb molecule, and that the transcripts specifically accumulate just before plastid division. Phylogenetic analysis indicated that C. caldarium RK-1 and other eukaryotic ftsZ genes are the descendants of cyanobacterial ftsZ genes, supporting the current agreement that FtsZ is involved in plastid division.

Sonographic assessment of osteochondritis dissecans of the humeral capitellum

OBJECTIVE

The purpose of this study was to determine the efficacy of sonography for revealing osteochondritis dissecans of the humeral capitellum.

SUBJECTS AND METHODS

Twenty-seven patients with capitellar osteochondritis dissecans (27 males; range, 11-20 years; mean age, 14 years) underwent radiography and sonography performed with a 7.5-MHz mechanical sector probe. Lesions were assessed as stable or unstable. The sonographic assessment was compared with radiographic assessment in 27 patients, MR assessment obtained in 10, and surgical findings in 15.

RESULTS

Sonographic assessment agreed with radiographic assessment in 23 of the 27 patients, MR assessment in nine of the 10, and surgical findings in 14 of the 15. Sonography revealed that two lesions, which had been underestimated on radiography, were unstable.

CONCLUSION

Sonography facilitates the assessment of capitellar lesions so that treatment can be optimized.

Nonoperative treatment of osteochondritis dissecans of the humeral capitellum

We examined 24 patients with osteochondritis dissecans of the humeral capitellum to determine the results of nonoperative treatment. The average age of the patients at the initial examination was 13.3 years (range, 11 to 16). All the patients were advised to stop heavy use of the elbow for 6 months. At the last examination, at a mean follow-up period of 5.2 years, 4 patients (17%) had no residual elbow pain, 7 (29%) had pain only with heavy activities, and 13 (54%) had pain with activities of daily living. Final radiographs were obtained for 15 lesions, of which 3 lesions were assessed as healed, 3 as improved, and 9 as not improved. Five of 11 lesions in the early stage and all 4 advanced lesions failed to show radiographic improvement. These results suggest that osteochondritis dissecans of the capitellum has only a slight tendency to heal, and that instability can cause failure of the lesion to heal.

Two types of ftsZ genes isolated from the unicellular primitive red alga Galdieria sulphuraria

FtsZ plays a crucial role in bacterial cell division, and may be involved in plastid division in eukaryotes. To investigate the evolution of the dividing apparatus from prokaryotes to eukaryotes, the ftsZ genes were isolated from the unicellular primitive red alga Galdieria sulphuraria. Two ftsZ genes (GsftsZ1 and GsftsZ2) were isolated. This suggests that duplication and divergence of the ftsZ gene occurred in an early stage of plant evolution. A comparison of the FtsZs of G. sulphuraria and other organisms shows that FtsZ is highly and universally conserved among prokaryotes, primitive eukaryotic algae, and higher plants. The GsftsZ2 gene seems to contain an intron. Southern hybridization analysis of the G. sulphuraria chromosomes separated by CHEF revealed that each ftsZ gene and its flanking region may be duplicated.

[Clinical investigation on endobronchial tuberculosis]

In order to assess the clinical features and clinical courses of endobronchial tuberculosis, which included trachea to segmental bronchus, we studied 34 cases of patients who were admitted to TB ward of International Medical Center of Japan from 1994 to 1997. We noticed a higher incidence in females and in the main bronchus. Cough was the most common complaint seen in 97% of cases. The duration of symptoms before the initiation of antituberculous chemotherapy was long (on the average 6 months), and they were often treated as bronchial asthma or bronchitis. Bronchoscopic examination is necessary for diagnosis. The scars sometimes gave rise to severe stenosis, especially when the lesion developed to an advanced stage or circumscribed the lumen before treatment. We tried INH inhalation with systemic chemotherapy. Although rapid improvement was suggested by this method, yet no significant difference was seen in the results for the efficacious prevention of stenosis. Five cases required surgical intervension (bronchoplasty and lobectomy) in order to avoid atelectasis or secondary infection. Early diagnosis and appropriate treatment are most important, and bronchoscopic examination is essential in early diagnosis.

Surgical repair of acute collateral ligament injuries in digits with the Mitek bone suture anchor

Eighteen acute grade III collateral ligament injuries were treated by using the Mitek bone suture anchor. Seven were thumb metacarpophalangeal joint injuries, and eleven were finger proximal interphalangeal joint injuries. Seventeen patients were followed more than 12 months after surgery. All patients were able to use the digits in daily living activities within 5 weeks after surgery, and return to their original work or sports activities within 12 weeks. Pain was completely relieved in 15 patients. Loss of joint motion averaged 7 degrees. In all joints the postoperative lateral stress angle was within 10 degrees of that of the contralateral digit.

[Drug consultation for patients who present with symptoms like dementia]

It is a lowering of compliance in taking drugs of patients who present with symptoms like dementia that being impairment in a therapy for disease. We started drug consultation to that one at home care, because of improvement of non-compliance in taking drugs. Improvement of consciousness in taking drugs for patients and consciousness in necessity of taking drugs for their family that be brought about by our drug consultation could be made progress of compliance in taking drugs.

[Diagnosis of pulmonary tuberculosis by the amplicor test for Mycobacterium tuberculosis in induced sputum]

The polymerase chain reaction (PCR) technique was compared with the conventional smear and culture method for the detection and identification of Mycobacterium tuberculosis in 25 induced sputa samples. Sputum induction was performed with an ultrasonic nebulizer using 3% hypertonic saline in 27 previously untreated patients suspected of active pulmonary tuberculosis clue to chest X-ray findings, but who were unable to spontaneously expectorate sputum. All patients received anti-tuberculosis drugs for at least 6 months after sputum induction. Two patients could not expectorate sputum after hypertonic saline inhalation. Microscopy failed to detect positive acid-fast bacilli in 25 induced sputa samples. Induced sputa were both PCR- and culture-positive for 10 patients, PCR-positive and culture-negative for 4 patients, and PCR-negative and culture-positive for 2 patients. These results suggest that the PCR method is useful in diagnosing tuberculosis in induced sputum, and that the results of PCR and culture Procedures can complement each other.

Second fracture of the distal humerus after varus malunion of a supracondylar fracture in children

Nine children sustained a second fracture of the distal humerus after union of an ipsilateral supracondylar fracture which had healed with cubitus varus. There were eight boys and one girl with a mean age of five years (1 to 8) at the time of the second fracture which occurred at a mean of 1.5 years after the first. In all patients, the second fracture was an epiphyseal injury of the distal humerus, either associated with a fracture of the lateral metaphysis below the site of the previous supracondylar fracture, or a fracture-separation of the entire distal humeral epiphysis. This suggests that the physis and epiphysis tend to be more subject to injury than the metaphysis of the distal humerus in children who have had a previous supracondylar fracture with varus malunion.

Second fracture of the distal humerus after varus malunion of a supracondylar fracture in children

Nine children sustained a second fracture of the distal humerus after union of an ipsilateral supracondylar fracture which had healed with cubitus varus. There were eight boys and one girl with a mean age of five years (1 to 8) at the time of the second fracture which occurred at a mean of 1.5 years after the first. In all patients, the second fracture was an epiphyseal injury of the distal humerus, either associated with a fracture of the lateral metaphysis below the site of the previous supracondylar fracture, or a fracture-separation of the entire distal humeral epiphysis. This suggests that the physis and epiphysis tend to be more subject to injury than the metaphysis of the distal humerus in children who have had a previous supracondylar fracture with varus malunion.

[Tuberculosis of the central nervous system experienced at the International Medical Center of Japan]

In spite of recent advances in diagnosis and chemotherapy of tuberculosis, prognosis of tuberculosis of the central nervous system (CNS) is still poor. We evaluated clinical characteristics of 14 patients with the CNS tuberculosis (10 male and 4 female, 21 to 71 years of age) who were hospitalized at IMCJ from 1988 to 1997. Twelve patients had tuberculous meningitis (2 of them had also intracranial tuberculoma), 1 had intracranial tuberculoma and 1 had spinal cord tuberculosis. For the acid-fast bacilli, the smears of cerebrospinal fluids (CSF) were all negative but the cultures for M. tuberculosis were positive in 5. Using PCR method, M. tuberculosis was identified from CSF specimens in 2 out of 9 culture negative patients, thus suggesting the usefulness of the PCR for the rapid diagnosis of CNS tuberculosis. The adenosine deaminase (ADA) levels in CSF may provide another diagnostic clue because they were elevated in 8 out of 10 cases. It is to be noted that there were three patients who developed clinical manifestations of CNS tuberculosis after the initiation of chemotherapy for pulmonary tuberculosis. In the last five cases, four-drug regimen which included PZA, was used with a good result. The success could be related to the addition of PZA which penetrates blood-brain barrier just as good as INH. Two patients died and one remains unconscious with severe neurological sequelae. The present study indicates that positive CSF culture, hydrocephalus and consciousness disturbance are important factors in determining poor prognosis of the CNS tuberculosis.

Antimalarial activity and nucleoside transport inhibitory activity of the triterpenic constituents of Cimicifuga spp

The in vitro antimalarial activity against human malaria parasite (Plasmodium falciparum, FCR-3 strain) was examined using 59 triterpenoids obtained during studies on the triterpenic constituents of Cimicifuga spp. The 50% effective concentration values (EC50) of 25 active triterpenoids were 1.0-3.0 microM, and 19 of the compounds had a common 16, 23:23, 26:24, 25-triepoxy group in the side-chain moieties. Among the active triterpenoids, 9 also showed significant inhibition of nucleoside transport in mouse splenocytes. A relationship between the antimalarial activity and the inhibition of nucleoside transport involving these triterpenoids is discussed.

Functional results of low median and ulnar nerve repair with intraneural fascicular dissection and electrical fascicular orientation

Twenty-eight low median nerve injuries and 23 low ulnar nerve injuries were repaired using intraneural fascicular dissection and electrical fascicular orientation. Eleven freshly lacerated nerves were seen within 48 hours after injury; 40 nerve lacerations were chronic. Fascicular orientation between sensory and motor fascicles at the proximal nerve end could be accurately differentiated in 47 nerves (92%) independent of whether it was acute or chronic. At the distal nerve end in fresh lacerations, the motor fascicles could be determined conclusively by muscle contraction with sequential electrical stimulation of the fascicles. In chronic nerve lacerations, the distal fascicles could be estimated anatomically after internal neurolysis. After fascicular orientation, nerves were repaired with end-to-end group fascicular suture or interfascicular sural nerve grafting. Twenty-four nerves repaired with end-to-end suture and 13 nerves repaired with nerve grafting were monitored more than 25 months. Satisfactory sensory results (i.e., S3+ or S4 functions) were obtained in 29 nerves (78%) and M4 or M5 motor functions were achieved in 29 nerves (78%). There were no patients who needed additional tendon transfers to reconstruct thumb opposition or to correct claw finger deformity. These results suggest that low median or ulnar nerve lacerations, whether acute or chronic, partial or complete, may be successfully repaired with the aid of electrical fascicular orientation with or without intraneural fascicular dissection.

[Reinfection tuberculosis at a day-laborers' facility equipped with a sauna]

Restriction-fragment-length polymorphism (RFLP) analysis was used to study one outbreak of reinfection pulmonary tuberculosis at a day-laborers' facility equipped with a sauna. The results were interpreted in conjunction with clinical and epidemiologic data. The DNA prove was derived from the insertion sequence IS 6110. A 63-year-old man who stayed at a day-laborers' facility for eight months was found to have advanced cavitary lung disease with sputum smears strongly positive for acid-fast bacilli. One year later a 46-year-old man staying at the same facility for 24 months was also found to have sputum-positive tuberculosis. The 46-year-old man had undergone treatment for tuberculosis 16 years previously and showed radiographic evidence of previous lung damage from tuberculosis. The second man had no tubercule bacilli in sputum when the 63-year-old man was found to have sputum-positive tuberculosis. The organisms isolated from these two men were both drug sensitive and had a similar RFLP pattern which suggests that 63-year-old man was the source of this outbreak and that pulmonary tuberculosis in the 46-year-old man was caused by exogenous reinfection. We conclude that exogenous reinfection may have been one pattern of tuberculosis transmission in this high-risk environment.

[Drug consultation and at home care--the present situation and the point at issue in our hospital]

We began drug consultation in our hospital and at home care about one year ago, because of progress in the quality of medical care. As the method for drug consultation, we tried to educate patients using our own pamphlets. It was assumed that the education was important not only for the patients but also for their family. Again, it was assumed that the usefulness of a conference with doctors, nurses, MSW and us made for better compliance in taking drugs, assured early detection of side effects and better management of the disease. With home care, it is supposed that the drug consultation will be carried out by clinical pharmacists will make for progress in the quality of medical care.

Applications of the long and accurate polymerase chain reaction method in yeast molecular biology: direct sequencing of the amplified DNA and its introduction into yeast

A DNA fragment longer than 10 kb can be amplified by the long and accurate polymerase chain reaction (LA-PCR) method. We demonstrate here applications of this technique in molecular biological studies of Saccharomyces cerevisiae. We have shown that DNA fragments amplified by LA-PCR can be directly used as a template in the chain-termination sequencing protocol, making it possible to quickly identify the DNA insert of yeast genomic library clones. We have also shown that the amplified yeast DNA can easily be introduced into yeast by co-transformation with linearized vector DNA. Overlapping DNA between the amplified yeast fragment and the vector must be more than 20 bp long in order to obtain 90% or more correct recombinant plasmids. These results suggest that simple amplification of yeast clones by LA-PCR can replace the previous procedures of yeast clone recovery, consisting of transformation of Escherichia coli, propagation of plasmids in E. coli and preparation of plasmid DNA.