Association of plasmid integrative J7W-1 prophage with Bacillus thuringiensis strains

A region homologous to the genome of plasmid integrative phage J7W-1 was detected in the largest plasmid in 3 out of 22 type strains of Bacillus thuringiensis, dendrolimus (DEN), aizawai (AIZ) and indiana (IND). Phage induction by ethidium bromide observed particularly in the J7W-1 lysogen was identified in DEN and IND but not AIZ strains. The morphology of the phage induced in DEN and IND strains was identical to J7W-1, but the phage production in IND strain was lower as compared to the J7W-1 lysogen. Although the restriction analysis indicated that the prophage in DEN strain possessed a complete J7W-1 genome, modification and/or deletion had presumably occurred in AIZ and IND strains.

New radiographic projections for avulsion fractures of the lateral malleolus

We report two new radiographic projections for evaluating avulsion fractures at the lateral malleolus. We used seven freshly amputated legs with simulated avulsion fractures and radiopaque markers to assess their value. The projections allow accurate assessment of the displacement of fragments without superimposition, and also show whether they affect the anterior talofibular or the calcaneofibular ligament or both.

New radiographic projections for avulsion fractures of the lateral malleolus

We report two new radiographic projections for evaluating avulsion fractures at the lateral malleolus. We used seven freshly amputated legs with simulated avulsion fractures and radiopaque markers to assess their value.

The projections allow accurate assessment of the displacement of fragments without superimposition, and also show whether they affect the anterior talofibular or the calcaneofibular ligament or both.

[A case of successful hypospadias repair without infection using recombinant human granulocyte-colony stimulating factor (rhG-CSF) for idiopathic neutropenia]

A boy aged 1 year 8 months, who was referred to our hospital because of hypospadias, was followed for 17 months under a diagnosis of idiopathic neutropenia. He was given recombinant human granulocyte colony-stimulating factor (rhG-CSF) at a dosage of 37.5 micrograms/day for 2 days preoperatively. His absolute neutrophil count in peripheral blood increased to more than 500/microliter, and hypospadias repair (free graft method) was performed. RhG-CSF was administered on the first, sixth, and eleventh days after the operation, and the postoperative course was uneventful. During pediatric surgery in patients with neutropenia, appropriate administration of rhG-CSF may be useful for preventing infection.

A ventral pontine pathway promotes rhythmic activity in the medulla of neonate mice

We have developed in new-born mice a ventral tilted-horizontal slice preparation for pontine stimulation and recording of spontaneous respiratory-like rhythmic trains of glutamatergic excitatory postsynaptic potentials (EPSPs) in medullary neurons. Electrical stimulations (10-50 Hz for 100-500 ms) of the caudal pontine reticular formation triggered a burst of EPSPs, recycling of the rhythmic activity and persistent increase of the rhythmic behaviour. These results identify a ventral pontine pathway that promotes rhythm generating mechanisms in the medulla and probably derives from a population of lateral reticular neurons identified in the embryonic hindbrain and eliminated after inactivation of the early developmental gene Krox-20.

Serial gadolinium-enhanced MR imaging after lumbar disc resection: observation of the affected root

A prospective study was undertaken to clarify the relationship between postoperative morphological/pathological changes in the affected root and the clinical developments after disc resection. Gadolinium-enhanced magnetic resonance (MR) imaging was performed at 1 week, 5 weeks, 3 months, and 6 months after surgery for 28 patients of 34 consecutive patients who underwent single-level disc resection. Enhancement/thickening of the affected root was found to be 100%/89% at 1 week, 50%/57% at 3 months, and 32%/37% at 6 months after surgery. Patients with root enhancement and thickening at 3 and 6 months after surgery had less clinical improvement than patients without it. There was consistent correlation between postoperative clinical developments and nerve root enhancement/thickening in enhanced MR imaging. To use enhanced MR imaging as an evaluation tool after disc surgery might increase the diagnostic accuracy and reduce failed back surgery syndrome.

Novel biological response modifiers: phthalimides with tumor necrosis factor-alpha production-regulating activity

Novel N-substituted phthalimides (2-substituted 1H-isoindole-1,3-diones) were prepared, and their effects on tumor necrosis factor-alpha (TNF-alpha) production by human leukemia cell line HL-60 stimulated with 12-O-tetradecanoylphorbol 13-acetate (TPA) or okadaic acid (OA) were examined. A structure-activity relationship study of the N-phenylphthalimides and N-benzylphthalimides revealed that their enhancing effect on TPA-induced TNF-alpha production by HL-60 cells and their inhibiting effect on OA-induced TNF-alpha production by HL-60 cells are only partially correlated.

Groin pain associated with lower lumbar disc herniation

STUDY DESIGN

Retrospective clinical and magnetic resonance imaging study of patients with groin pain associated with lower lumbar disc herniation.

OBJECTIVES

To demonstrate the clinical features and magnetic resonance imaging findings of these patients.

SUMMARY OF BACKGROUND DATA

Patients with lumbar disc herniation sometimes report groin pain. Little mention has been made, however, regarding the clinical features of groin pain stemmed from lower lumbar disc herniation until now, with only Murphey referring to groin pain in disc disease.

METHODS

A total of 512 patients were diagnosed with singular lower lumbar disc herniation (L4-L5 and L5-S1) at Kakegawa City General Hospital between July 1990 and December 1993. Of these patients, 21 (4.1%) reported groin pain. The characteristic clinical features and magnetic resonance imaging findings of the 21 patients were investigated and compared with the features and findings of patients with no groin pain.

RESULTS

Patients with groin pain had a higher mean age and lower rate of low back pain, and L4-L5 discs were more likely to be involved than L5-S1 discs. In their magnetic resonance images, herniation tended to be more central than in patients with no groin pain.

CONCLUSIONS

Elderly patients with L4-L5 protruding herniation of the anulus fibrosus were most likely to experience groin pain. The sinuvertebral nerve that innervates the posterior anulus fibrosus, the posterior longitudinal ligament, and the dura was indicated as the afferent nerve of groin pain.

Two distinct chondroitin sulfate ABC lyases. An endoeliminase yielding tetrasaccharides and an exoeliminase preferentially acting on oligosaccharides

Crude enzyme obtained from chondroitin sulfate-induced Proteus vulgaris NCTC 4636 has been fractionated into 1) an endoeliminase capable of depolymerizing chondroitin sulfate and related polysaccharides to produce, as end products, a mixture of Delta4-unsaturated tetra- and disaccharides and 2) an exoeliminase preferentially acting on chondroitin sulfate tetra- and hexasaccharides to yield the respective disaccharides. Isolation of the two enzymes was achieved by a simple two-step procedure: extracting the enzymes from intact P. vulgaris cells with a buffer solution of nonionic surfactant and then treating the extract by cation-exchange chromatography. Each of the enzymes thus prepared was apparently homogeneous as assessed by SDS-polyacrylamide gel electrophoresis and readily crystallized from polyethylene glycol solutions. Both enzymes acted on various substrates such as chondroitin sulfate, chondroitin sulfate proteoglycan, and dermatan sulfate at high, but significantly different, initial rates. They also attacked hyaluronan but at far lower rates and were inactive to keratan sulfate, heparan sulfate, and heparin. Our results show that the known ability of the conventional enzyme called "chondroitinase ABC" to catalyze the complete depolymerization of chondroitin sulfates to unsaturated disaccharides may actually result from the combination reactions by endoeliminase (chondroitin sulfate ABC endolyase) and exoeliminase (chondroitin sulfate ABC exolyase).

Histologic changes in the intervertebral disc after intradiscal injections of methylprednisolone acetate in rabbits

STUDY DESIGN

Histologic changes in the intervertebral disc were evaluated by light and electron microscopy after an intradiscal injection of methylprednisolone acetate.

OBJECTIVE

To evaluate the histologic changes that occur in the disc after an intradiscal injection of cortico steroids.

SUMMARY OF BACKGROUND DATA

Several orthopedic surgeons have managed lumbar disc herniation with intradiscal steroid injection. Few studies have addressed the histologic changes after this treatment.

METHODS

Thirty rabbits were surgically treated. Rabbits were divided into two groups. Group A: 25 rabbits underwent intradiscal steroid injections. Methylprednisolone acetate was injected into the L3-L4 disc, whereas methylprednisolone sodium succinate was injected into the L4-L5 disc. Physiologic saline was injected into the L5-L6 disc as a control. Groups of five rabbits were killed 1 day, 1, 4, 12, and 24 weeks after the injection and subjected to microscopic evaluation. Group B: Another five rabbits underwent an injection of polyethylene glycol 4000, a vehicle for methylprednisolone acetate, into the L3-L4 and L4-L5 discs. All five rabbits were killed 24 weeks after the injection and subjected to microscopic evaluation.

RESULTS

Group A: Light microscopic evaluation showed tissue in the nucleus pulposus, and the inner layer of the anulus fibrosus had degenerated in the methylprednisolone acetate group killed 24 weeks after the injection. Matrix vesicles, an indication of primary tissue calcification, were observed by electron microscopy. In the methylprednisolone sodium succinate group and saline group, however, no histologic changes were observed. Group B: Degeneration of the nucleus pulposus and primary tissue calcification were observed in the discs of all rabbits.

CONCLUSIONS

Methylprednisolone acetate and its vehicle polyethylene glycol cause degeneration and primary calcification in discs.

Coherent inspiratory oscillation of cranial nerve discharges in perfused neonatal cat brainstem in vitro

1. To understand the neural organization of respiratory movement control and its developmental transformation, we studied the temporal characteristics of inspiratory activities, especially nerve-to-nerve short-term synchronization, in an in vitro preparation of the isolated, perfused brainstem of kittens aged 0-14 days (postnatal day (P) 0-14). 2. In the inspiratory discharges of facial, vagus, glossopharyngeal and hypoglossal nerves, a stable oscillation with a period of 30-40 ms (i.e. approximately 30 Hz) was observed in all preparations examined. In addition, we demonstrated that this oscillation presents a strong short-term synchrony between distinct inspiratory nerves. This nerve-to-nerve synchronization was already apparent at approximately 12 h after birth. The degree of synchronization as evaluated by coherence spectral analysis was larger than 0.85 in all cases at any age examined. 3. This nerve-to-nerve coherence was not affected by changes in temperature (28-36 degrees C), whereas respiratory rate, oscillation frequency and oscillation amplitude as estimated by power spectral analysis were highly temperature sensitive. 4. The nerve-to-nerve synchronization, as well as the approximately 30 Hz oscillation, remained unchanged after a pontomedullary transection, indicating that the medullary network, completely isolated from other structures and afferents, is sufficient to produce both fast oscillation and nerve-to-nerve synchronization. 5. Based on these observations in vitro, we conclude that nerve-to-nerve coherent inspiratory oscillation generated in the brainstem is already functional early in life.

Reorganization of pontine rhythmogenic neuronal networks in Krox-20 knockout mice

We have shown previously that the inactivation of the zinc finger gene Krox-20 affects hindbrain segmentation, resulting in the elimination of rhombomeres 3 and 5. We demonstrate here that Krox-20 homozygous mutant mice exhibit abnormally slow respiratory and jaw opening rhythms, indicating that a modification of hindbrain segmentation influences the function of neuronal networks after birth. Central neuronal networks that control respiratory frequency are made predominantly depressant by the elimination of a previously undescribed rhythm-promoting system. Recordings of rhythmic activity from the isolated hindbrain following progressive tissue transections indicate that the reorganization takes place in the caudal pontine reticular formation. The newborn (PO) Krox-20-/- mice, in which apneas are ten times longer than in wild-type animals, may be a valuable model for the study of life-threatening apneas during early infancy.

Successful treatment of chylothorax by bleomycin for Gorham's disease

A patient with idiopathic osteolysis in the thoracolumbar spine who developed severe chylothorax after a spinal operation is described. Irradiation and pleural adhesion therapies with minocycline and bleomycin were undertaken to control the chylothorax. Pleural adhesion therapy with bleomycin proved effective in treating this patient. Magnetic resonance imaging was performed to detect the lesion. T1 weighted imaging was particularly useful in diagnosing the lesion and evaluating the degree of fusion in the spine.

Arthritis in mice induced by a single immunisation with collagen

OBJECTIVE

To determine whether collagen induced arthritis (CIA) in mice can be satisfactorily induced by a single immunisation and whether this model has some advantages compared with conventional CIA, which is induced by two immunisations.

METHODS

The incidence of arthritis was observed under different immunisation conditions (variation of species of Mycobacterium included in complete Freund's adjuvant and the method of emulsification) and immunological, histopathological, and pharmacological features were examined.

RESULTS

Under optimum immunisation conditions, joint inflammation developed two to three weeks after the primary immunisation with an incidence of 100% at four to five weeks. The progression of the arthritis was mild and was associated with moderate increases in concentrations of serum IgG against type II collagen. This CIA model was similar to the conventional model in histopathological and pharmacological features.

CONCLUSIONS

Murine CIA could be successfully induced by a single immunisation. An important feature of this model was a mild progression of joint inflammation. This feature seems to be of benefit for monitoring the development of arthritis from an early stage in the disease and for the development of novel antirheumatic drugs for such early stage patients.

Serial magnetic resonance imaging follow-up study of lumbar disc herniation conservatively treated for average 30 months: relation between reduction of herniation and degeneration of disc

The natural history of lumbar disc herniation in conservatively treated patients is not entirely clear. This study was undertaken to clarify the relation between morphologic changes in the herniation and the clinical course. Serial magnetic resonance imaging studies were performed an average of 4.4 times in 30 patients in a 30-month-average period. The Japanese Orthopaedic Association (JOA) score and straight leg raising (SLR) test were improved, with the average reduction ratio of the herniation 15 and 18% on the sagittal and axial images, respectively. The JOA score and SLR test showed the most improvement within 1 year, with little change noted thereafter. In contrast, the disc herniation continued to reduce not only within 1 year, but also thereafter. Patients with progression of disc degeneration showed more marked regression of herniation than those in whom progression was not observed.

Experimental chemonucleolysis with chondroitinase ABC in monkeys

STUDY DESIGN

Experimental chemonucleolysis with chondroitinase ABC as compared with chymopapain was investigated in monkeys. The effects of these two enzymes were analyzed morphologically and biochemically.

OBJECTIVES

The results of the present study facilitate the clinical application of chondroitinase ABC.

SUMMARY OF BACKGROUND DATA

Many experimental studies on chemonucleolysis with chondroitinase ABC have been reported mostly in rabbits. Further examination in animals that are more similar to humans is necessary for its clinical application.

METHODS

Ten mature rhesus monkeys were used. Lumbar intervertebral discs from six monkeys were injected with either chondroitinase ABC, chymopapain, or physiologic saline. The animals were killed not more than 6 weeks after injection, and their discs were examined morphologically and biochemically. The remaining four monkeys were used for a longer follow-up study to determine the changes in chondroitinase ABC-injected discs.

RESULTS

Degenerative changes of discs were more severe with the injection of chymopapain, although the content of hyaluronic acid, chondroitin sulfate, and dermatan sulfate decreased more with the injection of chondroitinase ABC. In a longer follow-up study, chondroitinase ABC-injected discs recovered somewhat morphologically and biochemically.

CONCLUSIONS

The results confirm that selective degradation is achieved with chondroitinase ABC in vivo in monkeys and that chondroitinase ABC is less toxic to discs than chymopapain is. From these considerations, chondroitinase ABC is believed to have a high potential for clinical application.

Congenital hypopituitarism with hypoplasia of the anterior pituitary gland and a normal posterior pituitary lobe

We report a female infant with congenital hypopituitarism. All anterior pituitary hormones were deficient, and the anterior pituitary gland was undetectable on magnetic resonance images. Antidiuretic hormone secretion was appropriate, and the posterior lobe was localized at the end of the stalk, in the sella. These observations suggest that the posterior pituitary gland may develop independently of the anterior lobe.

Effects of chondroitinase ABC on degenerative intervertebral discs

The effects of chondroitinase ABC on surgically induced degenerative rabbit intervertebral discs were determined during a 12-week period by magnetic resonance imaging, radiography, and histologic examination. Rabbit intervertebral discs were surgically extruded, inducing disc degeneration 12 weeks before injection of chondroitinase ABC. Magnetic resonance imaging showed a hypointense area in the center of the surgically induced disc degeneration. After injection of chondroitinase ABC, the hypointense area became more intense, but reversed somewhat by the end of the 12-week period. Additional evidence of the effects of chondroitinase ABC on a surgically induced degenerative disc model was shown by radiographic evidence of shrinkage of the disc after injection. Histologic examination revealed a fibrous degenerative disc induced by surgical extrusion. However, the staining properties of the matrix of the nucleus pulposus was similar to that of normal discs before chondroitinase ABC injection, but diminished after the injection, with slight recovery at 12 weeks. The results suggest that chondroitinase ABC induces chemonucleolysis in the degenerated disc. Also, chondroitinase ABC does not destroy the degenerative disc matrix ability to regenerate after 12 weeks.

Rhythm generation in the segmented hindbrain of chick embryos

1. The embryonic hindbrain of chick is segmented until stage 24, when it starts to generate rhythmic activities in cranial nerves. In order to recognize a possible influence of segmentation on the organization of neuronal systems generating motor rhythms, the activity of trigeminal, facial, glossopharyngeal, vagal and hypoglossal nerves was studied during embryonic stages 24-36, by simultaneous recording of different cranial nerves in an isolated, superfused chick hindbrain preparation. 2. Highly correlated recurrent episodes of cyclical burst discharges occurred in all nerves studied (correlation coefficients, 0.8 +/- 0.1) throughout stages 24-36. 3. Such coactivation is unlikely to be due to monosynaptic connections between widely divergent premotor neurons and motoneurons, or between motoneurons themselves, because no short-term correlation was apparent in the millisecond range between activities of different motor nerves. 4. Complete transverse or midsagittal sectioning of the hindbrain disrupted coactivation of nerves located at distinct rostrocaudal levels or occupying an ipsi- or contralateral position, respectively, while sparing the ability of individual nerves to generate rhythmic activity. Each hindbrain segment thus contains bilaterally the motor nuclei together with their own rhythm generator. Coactivation of motor patterns appears to result from intersegmental and cross-median connections between these rhythm generators. 5. The results are in keeping with the hypothesis of a segmental organization of the primordial hindbrain rhythm generator and give further support to the early determination of both the anatomical and the functional fate of neurons in this region of the vertebrate central nervous system.

Involvement of NMDA receptors in the respiratory phase transition is different in the adult guinea pig in vivo and in the isolated brain stem preparation

1. We investigated the involvement of N-methyl-D-aspartate (NMDA) receptors in the respiratory pattern in an in vitro preparation of adult brain stem compared with in vivo conditions in the guinea pig. 2. In vivo, combining administration of the NMDA channel blocker dizocilpine (MK-801) (3 mg/kg) with a surgical section of the vagus nerves induced an apneustic type of respiration characterized by long inspiratory "holds," as has been shown in other species. The same effect was observed in hypothermic animals (30 degrees C). 3. The isolated in vitro brain stems from these apneustic animals did not present a prolonged inspiratory phase. A second dose of dizocilpine (100 microM perfused vascularly did not induce apneusis, even after increasing brain stem temperature to 35.5 degrees C. 4. In another group of isolated brain stems of adult guinea pigs anesthetized with pentobarbital sodium before decapitation, we perfused dizocilpine and NMDA through the basilar artery. The duration of periodic inspiratory motor activity recorded from the hypoglossal nerve was unaffected by dizocilpine (1-100 microM) or the competitive NMDA antagonist D- or DL-2-amino-5-phosphonopentanoic acid (100 microM and 1 mM), although respiratory frequency decreased. The increase in respiratory activity produced by vascularly perfused NMDA (25-100 microM) was blocked by dizocilpine (100 microM). 5. We conclude that the central mechanism of inspiratory termination in the vagotomized adult guinea pig requires the activation of NMDA receptors in vivo but not in vitro. This difference is not due to the hypothermic environment in vitro. Possible mechanisms for phase switching in vitro are discussed.