Vascular proliferation and blood supply during distraction osteogenesis: a scanning electron microscopic observation

This scanning electron microscopic study examined the spatial and temporal features of proliferating vessels of regenerating bone tissue and blood supply during distraction osteogenesis. A rat model of tibial lengthening was used with a protocol divided into a latency period of 7 days, a distraction period that lasted 14 days with a daily distraction rate of 0.5 mm in two steps, and a consolidation period of 21 days. Vascular casting was done on the hindlimbs before osteotomy and on postoperative days 7, 14, 21, 28, and 42. Scanning electron microscopic findings were correlated with radiological and histological observations. On days 7 and 14, the proliferation of periosteal vessels was pronounced and there was distinct subperiosteal bone formation on the osteotomized surfaces. On day 21, vascular branches from the medullary canal of the host bone formed a vascular network, which gave rise to multiple axial, straight vascular branches, running parallel to the direction of distraction, toward the interzone, in accordance with the progress of mineralization. On day 28, the periosteum provided vascularization to the peripheral side of the interzone whereas the center of the interzone was still relatively avascular. On day 42, the periosteal and medullary vascular channels were completely connected at the distraction site including the interzone, which was occupied by developing and mature bone trabeculae. These results suggest that vascular proliferation occurs actively during the latency and distraction periods and then gradually decreases over time. A close temporal and spatial relationship exists between formation of regenerated bone and vascular proliferation of the periosteum and medullary canal.

Focal fibrocartilaginous dysplasia of long bones: report of eight additional cases and literature review

We report eight additional cases of focal fibrocartilaginous dysplasia (FFCD) in the proximal tibia (five), distal ulna (one), and distal femur (two). Spontaneous, complete resolution of the lesion was observed in two tibiae and one ulna. Three tibial lesions with genu varum deformity were managed with osteotomy. Two femoral FFCDs caused persistent or progressive deformity: one genu valgum with patellar dislocation, and one genu varum. These patients underwent concomitant deformity correction and lengthening by the Ilizarov method. The final results were satisfactory in all patients except one, who underwent valgus tibial osteotomy and developed mild postoperative genu valgum. The analysis of a total of 46 cases in the literature and our experience suggests that (a) FFCD has a wide histopathologic spectrum, ranging from purely dense, fibrous tendon-like tissue to benign fibrocartilaginous tissue; (b) at least 45% of tibial FFCD demonstrates progressive, spontaneous resolution; (c) in contrast, femoral and humeral FFCDs appear to have a slim possibility of spontaneous regression of the deformity; and (d) corrective osteotomy is indicated when the deformity is increasing or persistent, or when the existing deformity is severe enough to jeopardize adjacent joint mechanics and alignment.

The Sprengel deformity. Morphometric analysis using 3D-CT and its clinical relevance

We evaluated scapular dysplasia and malposition in 15 patients with the Sprengel deformity using three-dimensional CT (3D-CT). The shape, height-to-width ratio, the areas of both scapulae, the anterior curvature of the supraspinous portion and glenoid version were assessed on scapular posterior, medial and inferior views. The degree of rotation and superior displacement were measured on the trunk posterior view. The omovertebral connection was also assessed and correlated with the operative findings. Most of the affected scapulae had a characteristic shape with a decrease in the height-to-width ratio and were larger than the contralateral scapulae. There was an inverse relationship between scapular rotation and superior displacement. The typical curve of the supraspinous portion of the scapula was seen in only three cases. There was no significant difference in glenoid version. The point of tethering of the omovertebral connection may determine the shape, rotation and superior displacement of the scapula. 3D-CT was helpful in delineating the deformity in detail, and in planning scapuloplasty.

Three-dimensional esophageal varix model quantification of variceal volume by high-resolution endoluminal US

BACKGROUND

The purpose of this study was to evaluate the accuracy and reproducibility of three-dimensional volume measurements by high-resolution endoluminal ultrasound in an esophageal varix model.

METHODS

An esophageal varix model was made by filling three esophageal dilatation catheters with various volumes of water. A 20 MHz ultrasonography transducer was then pulled along the length of the catheters at a constant rate (1.25 mm/sec) while videotaping the procedure. Cross-sectional surface area measurements of each catheter were taken every second and the cross-sectional surface area was multiplied by the length of each catheter, as determined by high-resolution endoluminal ultrasound, to determine the volume in each catheter. Interobserver variability was calculated, and three-dimensional reconstruction was performed.

RESULTS

The measured volumes corresponded closely with the actual volumes with an error ranging from 0% to 15.4%. The correlation between actual and measured volumes was r = 0.988. The interobserver variability ranged from r = 0.951 to r = 0.994. Actual esophageal varices were then imaged in a similar fashion to determine the feasibility of this method in patients with esophageal varices.

CONCLUSIONS

High-resolution endoluminal ultrasound is an accurate and reproducible method of measuring volumes in an esophageal varix model and can be used in a clinical setting to determine variceal volume. Volume studies are now underway in human subjects.

The molecular genetics of chemotaxis: sensing and responding to chemoattractant gradients

Chemotaxis plays a central role in various biological processes, such as the movement of neutrophils and macrophage during wound healing and in the aggregation of Dictyostelium cells. During the past few years, new understanding of the mechanisms controlling chemotaxis has been obtained through molecular genetic and biochemical studies of Dictyostelium and other experimental systems. This review outlines our present understanding of the signaling pathways that allow a cell to sense and respond to a chemoattractant gradient. In response to chemoattractants, cells either become polarized in the direction of the chemoattractant source, which results in the formation of a leading edge, or they reorient their polarity in the direction of the chemoattractant gradient and move with a stronger persistence up the gradient. Models are presented here to explain such directional responses. They include a localized activation of pathways at the leading edge and an "inhibition" of these pathways along the lateral edges of the cell. One of the primary pathways that may be responsible for such localized responses is the activation of phosphatidyl inositol-3 kinase (PI3K). Evidence suggests that a localized formation of binding sites for PH (pleckstrin homology) domain-containing proteins produced by PI3K leads to the formation of "activation domains" at the leading edge, producing a localized response.

Validation of volume measurements in esophageal pseudotumors using 3D endoluminal ultrasound

The purpose of this study was to validate the accuracy and reliability of volume measurements using three-dimensional (3D) endoluminal ultrasound (ELUS) in canine pseudotumor esophageal specimens in vitro. Pseudotumors were created by injecting various volumes of US gel (0.1-1.0 ml) into canine esophageal specimens. A stepping-motor was used to pull either a 9, 12.5 or 20 MHz transducer through the lumen of the specimen at 1.5 mm/s. Images were downloaded to a LIFE computer system for 3D reconstruction. Volume measurements were made by two investigators and compared to spiral CT images. Averaging across all measurements, the average magnitude of error was 8.7% in individual US determinations and 11. 9% in CT measures. Volumes estimated from images spaced 0.5 and 1.0 mm apart, from images in the original and reconstructed planes, and from different scan frequencies, produced percentage errors that were not statistically significantly different from each other on ELUS. 3D ELUS can be used accurately and reproducibly to measure tumor volumes with a low mean percent in vitro.

Changes in blood flow during one stage lengthening of bone: an experimental study in rats

Distraction osteogenesis is a well-accepted method of bone lengthening. Its disadvantages, however, are that it requires an external fixator and takes a long time. One-stage lengthening therefore offers certain advantages. A first point of reference for the safe limits of this procedure might be the changes of blood flow, and this is also the crucial factor in deciding on the appropriate method of lengthening, particularly where the hand or foot is involved. Using a laser Doppler flowmeter we measured blood flow in the dorsum of the foot after using bilateral minimonofixators to lengthen the tibias of 15 Sprague-Dawley rats. They were lengthened in four stages: stage 0 (before lengthening); stage I--12.5%; stage II--25%; and stage III--31.25% of lengthening. The blood flow during stage I decreased to 79% compared to that of stage 0; 16% during stage II; and 1% during stage III. This study suggests that the maximal permissible extent of lengthening might be less than a quarter according to the blood flow as suggested by this animal model.

Role of Rac in controlling the actin cytoskeleton and chemotaxis in motile cells

We have used the chemotactic ability of Dictyostelium cells to examine the roles of Rho family members, known regulators of the assembly of F-actin, in cell movement. Wild-type cells polarize with a leading edge enriched in F-actin toward a chemoattractant. Overexpression of constitutively active Dictyostelium Rac1B(61L) or disruption of DdRacGAP1, which encodes a Dictyostelium Rac1 GAP, induces membrane ruffles enriched with actin filaments around the perimeter of the cell and increased levels of F-actin in resting cells. Whereas wild-type cells move linearly toward the cAMP source, Rac1B(61L) and Ddracgap1 null cells make many wrong turns and chemotaxis is inefficient, which presumably results from the unregulated activation of F-actin assembly and pseudopod extension. Cells expressing dominant-negative DdRac1B(17N) do not have a well-defined F-actin-rich leading edge and do not protrude pseudopodia, resulting in very poor cell motility. From these studies and assays examining chemoattractant-mediated F-actin assembly, we suggest DdRac1 regulates the basal levels of F-actin assembly, its dynamic reorganization in response to chemoattractants, and cellular polarity during chemotaxis.

The Dictyostelium LIM domain-containing protein LIM2 is essential for proper chemotaxis and morphogenesis

We have identified limB, a gene encoding a novel LIM domain-containing protein, LIM2, in a screen for genes required for morphogenesis. limB null cells aggregate, although poorly, but they are unable to undergo morphogenesis, and the aggregates arrest at the mound stage. limB null cells exhibit an aberrant actin cytoskeleton and have numerous F-actin-enriched microspikes. The cells exhibit poor adhesion to a substratum and do not form tight cell-cell agglomerates in suspension. Furthermore, limB null cells are unable to properly polarize in chemoattractant gradients and move very poorly. Expression of limB from a prestalk-specific but not a prespore-specific promoter complements the morphogenetic defects of the limB null strain, suggesting that the limB null cell developmental defect results from an inability to properly sort prestalk cells. LIM2 protein is enriched in the cortex of wild-type cells, although it does not colocalize with the actin cytoskeleton. Our analysis indicates that LIM2 is a new regulatory protein that functions to control rearrangements of the actin cytoskeleton and is required for cell motility and chemotaxis. Our findings may be generally applicable to understanding pathways that control cell movement and morphogenesis in all multicellular organisms. Structure function studies on the LIM domains are presented.

Primary small cell bronchogenic carcinoma in a 14-year-old boy

A 14-year-old Korean boy was admitted with cough, hemoptysis, and fever. A chest X-ray showed a solitary pulmonary mass and pneumonitis. Bronchial biopsy by fiberoptic bronchoscopy revealed a poorly differentiated small cell carcinoma. All of the staging information indicated that the patient had limited disease. During the 7 months following diagnosis, he received adjuvant chemotherapy in conjunction with radiotherapy. The size of the lesion was reduced by almost 50%. Small cell bronchogenic carcinoma has not been reported previously in childhood.

Brain lesion size and location: effects on motor recovery and functional outcome in stroke patients

OBJECTIVE

To investigate effects of brain lesion profiles that combined sizes and locations on motor recovery and functional outcome after stroke in hemiplegic patients.

DESIGN

Delimiting sizes (a threshold lesion size) of 5 primary locations were identified to establish brain lesion profiles based on magnetic resonance imaging findings 1 month after stroke. Motor and functional outcome were correlated with brain lesion profiles and other brain lesion factors to identify the most dominant factor.

SETTING

Medical center, rehabilitation department.

PARTICIPANTS

Fifty-five hemiplegic patients.

MAIN OUTCOME MEASURES

Brunnström's stages and Functional Independence Measure (FIM) scores were assessed 1 and 6 months after stroke.

RESULTS

With delimiting sizes for the cortical, corona radiata, internal capsule, putaminal, and thalamic regions set at 75, 4, .75, 22, and 12cm3, respectively, brain lesion profiles play a dominant role in determining final Brunnström's stages (Spearman's rho = .861, p < .01) and FIM score (Spearman's rho = .571, p < .01). Brunnström's and FIM scores had no or only weak negative relationship with either absolute or relative lesion size.

CONCLUSIONS

These findings may suggest that motor and functional outcomes after stroke correlate with brain lesion profiles (a combination of delimiting sizes and primary locations) more than with absolute or relative lesion sizes only. Delimiting sizes in determining final outcomes varied markedly according to the primary lesion locations.

Deletions in the 13q14 locus in adult lymphoblastic leukemia: rate of incidence and relevance

BACKGROUND

A putative tumor suppressor gene involved in chronic lymphocytic leukemia (CLL) has been localized to the 13q14 locus. Microsatellite analysis was used to test whether this locus also is involved in acute lymphoblastic leukemia (ALL) and its prognostic relevance determined.

METHODS

The authors analyzed 49 patients with adult ALL for deletions at the 13q14 locus using a battery of 6 microsatellite markers corresponding to this region (D13S260, STR257, D13S263, D13S153, D13S319, and AFMa301wb5).

RESULTS

Five of the 49 adult ALL patients analyzed (10%) showed loss of heterozygosity (LOH) or deletions at 13q14. Similar to CLL, the significant minimal deletions appeared to be localized between D13S260 and AFMa301wb5 and did not involve the retinoblastoma or BRCA2 genes. Among newly diagnosed patients, LOH was associated with shorter survival (P = 0.007).

CONCLUSIONS

These data suggest that the 13q14 gene, commonly deleted in CLL patients, also is deleted in some patients with adult ALL. Although the number of the cases in the current study is small, 13q deletions in ALL patients may play a role in the clinical behavior of this disease.

Establishment of a biological indicator for the radiation and safety of diagnostic ultrasound using apoptosis

We have studied, by a nonisotopic in situ end-labeling (ISEL) technique, the frequency of apoptosis in the intestinal crypt cell of adult mice and in the external granular layer(EGL) of the cerebellum of fetuses by gamma-ray irradiation from 60Co or diagnostic ultrasound exposure. The extent of changes following 200 cGy(1090 cGy/min) was studied at 2, 4, 6, 8, 12, or 24 hours after exposure. The maximal frequency was found 4-8 hours after exposure. The mice that received 18, 36, 54, 108, 198, 396 cGy of gamma-rays or diagnostic ultrasound (7.5 MHz, 4.2 mW, ISPTA = 7.9 mW/cm2, IsppA = 114.3 W/cm2) for 10 or 30 minutes were examined 6 hours after irradiation. Measurements performed after gamma-ray irradiation showed a dose-related increase in apoptotic cells in each of the mice studied. The dose-response curves were analyzed with alpha linear-quadratic model: the frequency (number per crypt) of apoptotic cells in the intestinal crypt of adult mice was y = (0.0386 +/- 0.004204)D + (-0.0000535 +/- 0.00001120)D2 + 0.15475(r2 = 0.952, y = apoptotic cell per crypt cell, D = dose in cGy), and the frequency (percentage of apoptotic cell in the EGL) of apoptotic cell in the EGL of fetus was y = (0.1349 +/- 1.175)D + (-0.001522 +/- 0.334)D2 + 0.0477(r2 = 0.981, y = % of apoptotic cell in the EGL, D = dose in cGy). In the experiment of ultrasound exposure, the frequencies of apoptosis were 0.181 +/- 0.055(10 minutes exposure) and 0.325 +/- 0.294 (30 minutes exposure) in the crypt cells and 0.106 +/- 0.130% (10 minutes exposure) and 0.167 +/- 0.220%(30 minutes exposure) in the EGL. We estimated the relative dose of the yield from the experiment with ultrasound by substituting the yield from ultrasound exposure into the curue from the gamma-irradiation. The relative doses of ultrasound exposure compared with gamma-irradiation were 0.692 cGy(10 minutes exposure) and 1.334 cGy(30 minutes exposure) in the experiment for crypt cells and 0.432 cGy(10 minutes exposure) and 0.885 cGy(30 minutes exposure) in the experiment for EGL. Although there is presently no evidence to indicate that diagnostic ultrasound involves a significant risk, it is not wise to use diagnostic ultrasound indiscriminately.

Late abnormal findings on high-resolution computed tomography after Mycoplasma pneumonia

BACKGROUND

The clinical course of Mycoplasma pneumonia is typically mild and self-limited. There are, however, several case reports of severe complication following this illness with considerable morbidity and mortality.

OBJECTIVES

This study was conducted to investigate, using high-resolution computed tomography (HRCT), the long-term pulmonary structural abnormalities after Mycoplasma pneumonia and to identify risk factors (chest radiograph findings, antibody titers, and host factors) that might increase the likelihood of developing the sequelae.

METHODS

Thirty-eight children requiring hospitalization attributable to Mycoplasma pneumonia were recruited by the retrospective examination of hospital records. They underwent HRCT after an interval of 1.0 to 2. 2 years. A control group of 17 children with the history of Mycoplasma upper respiratory infection was also studied after a similar interval.

RESULTS

Abnormal HRCT findings were present in 37% (14/38) of the pneumonia group, compared with 12% (2/17) of the control group. The abnormalities in the pneumonia group, which appeared alone or in combination, included mosaic perfusion (n = 12), bronchiectasis (n = 8), bronchial wall thickening (n = 4), decreased vascularity (n = 1), and air trapping on expiratory scan (9 of 29 tested). The area affected by these abnormalities, usually involving 2 or more lobes, corresponded in all cases to the location of the infiltrate on chest radiograph at the time of pneumonia. Between subjects with abnormal HRCT (n = 14) and normal HRCT (n = 24) in the pneumonia group, significant differences were observed in age at the time of pneumonia (mean +/- standard deviation: 5.3 +/- 2. 0 years vs 7.7 +/- 3.4 years) and peak antimycoplasma antibody titer (geometric mean [range of 1 standard deviation]; 1:7943 [3126-19 953] vs 1:3093 [832-11 482]).

CONCLUSIONS

We conclude that a considerable proportion of children with history of Mycoplasma pneumonia have abnormal findings on HRCT, suggestive of small airway obstruction and that younger age and higher antibody titer at the time of pneumonia may be risk factors for these sequelae.

Serial passage of MC3T3-E1 cells alters osteoblastic function and responsiveness to transforming growth factor-beta1 and bone morphogenetic protein-2

The murine-derived clonal MC3T3-E1 cell is a well-studied osteoblast-like cell line. To understand the effects of serial passages on its cellular function, we examined changes in cell morphology, gap junctional intercellular communication (GJIC), proliferation, and osteoblastic function between early passage (<20) and late passage (>65) cells. MC3T3-E1 cells developed an elongated, spindle shape after multiple passages. Intercellular communication decreased significantly (33%) in late vs. early passage cells. Transforming growth factor-beta1 (TGF-beta1) stimulated cell proliferation in early passage cells and induced c-fos expression, while it inhibited proliferation in late passage cells. Using alkaline phosphatase (ALP) activity and osteocalcin (OC) secretion as markers for osteoblastic function and differentiation, we demonstrated that both markers were significantly reduced after multiple cell passages. Bone morphogenetic protein-2 (BMP-2) significantly enhanced ALP activity and OC secretion in early passage cells while TGF-beta1 exerted an opposite effect. Both BMP-2 and TGF-beta1 had minimal effects on late passage cells. We conclude that serial passage alters MC3T3-E1 cell morphology, and significantly diminishes GJIC, osteoblastic function, TGF-beta1-mediated cell proliferation, and responsiveness to TGF-beta1 and BMP-2. Cell passage numbers should be clearly defined in functional studies involving MC3T3-E1 cells.

The histological spectrum of subperiosteal fibrocartilaginous pseudotumor of long bone (focal fibrocartilaginous dysplasia)

Clinicopathological features in six cases of focal fibrocartilaginous dysplasia (FFCD) which involved either the tibia (n = 4) or the femur (n = 2) were reviewed. All cases presented clinical and radiological characteristic features, and histopathological findings were analyzed in five of the six cases. The subject group comprised three boys and three girls, ages ranged from 12 to 18 months. Histologically, the individual lesions showed regional variation in cellularity, amount of fibrous and cartilaginous components. Paucicellular areas were mainly composed of dense fibrous tissue while more cellular areas contained foci of fibrocartilaginous element. The chondrocytes and stellate cells around cartilaginous area were positive for S-100 protein. One case contained both hyaline and fibrocartilage, and architecturally mimicked normal tendinous insertion. One case, which involved proximal tibia, was purely composed of fibrous tissue without fibrocartilage. All cases formed undulating and irregular borders against underlying cortical bone. Histopathologically variable spectrum suggests a strong possibility of undergoing transition from initial cellular and cartilagnous to late paucicellular, fibrous phase. Although any evidence that can explain basic pathogenesis or prognostic histological parameter is lacking, we believe that the term FFCD is not relevant because the presence of fibrocartilage is not an essential feature, and it can cause confusion with other pathological processes. We propose the term 'subperiosteal fibrocartilaginous pseudotumor of long bone' for this unique clinicopathological entity with which heterologous cartilaginous element can be associated.

Optimum ratio of distraction in double level tibial lengthening

The authors reviewed 43 double level tibial lengthenings by Ilizarov technique in 34 consecutive patients (6-31 years old), and investigated the factors affecting regenerate bone healing to determine the optimum ratio of distraction rate or magnitude of lengthening at the proximal and distal osteotomy sites. Length gain averaged 6.1 cm (range, 2.5-12.3 cm), equivalent to a 28% increase of the segment. The variables investigated included age, gender, concomitant deformity correction, etiology, and the amount of length gain. The healing index averaged 1.8 months per centimeter proximally and 2.8 months per centimeter distally. Age and the amount of length gain affected the healing index at proximal and distal lengthening sites. However, the proximal to distal healing index ratio, which averaged 0.72, was not affected by any parameters investigated. This study suggests that to minimize external fixation treatment time, the distraction rate, or amount of length gain, of the distal osteotomy site should be approximately 3/4 that of the proximal site in the double level tibial lengthening.

Correction of genu recurvatum by the Ilizarov method

The Ilizarov apparatus was used to carry out opening-wedge callotasis of the proximal tibia in ten patients who had suffered premature asymmetrical closure of the proximal tibial physis and subsequent genu recurvatum. In four knees, the genu recurvatum was entirely due to osseous deformity, whereas in six it was associated with capsuloligamentous abnormality. Preoperatively, the angle of recurvatum averaged 19.6 degrees (15 to 26), the angle of tilt of the tibial plateau, 76.6 degrees (62 to 90), and the ipsilateral limb shortening, 2.7 cm (0.5 to 8.7). The average time for correction was 49 days (23 to 85). The average duration of external fixation was 150 days (88 to 210). Three patients suffered complications including patella infera, pin-track infection and transient peroneal nerve palsy. At a mean follow-up of 4.4 years, all patients, except one, had achieved an excellent or good radiological and functional outcome.

Metatarsal lengthening in congenital brachymetatarsia: one-stage lengthening versus lengthening by callotasis

We retrospectively reviewed and compared the outcomes of 15 one-stage metatarsal lengthenings with intercalary bone graftings in 10 patients with those of nine metatarsal lengthenings by callotasis in five patients younger than 15 years. In the one-stage lengthening group, the diaphyseal osteotomy site was gradually distracted intraoperatively for 20-30 min to relax the surrounding soft tissues. In the callotasis group, lengthening was achieved with mini-Orthofix M-100. There was little difference in the outcomes between the two groups in terms of length gain, percentage increase, and complications. However, the period to achieve bony consolidation was longer in the callotasis group (2.7 months/cm) than in the one-stage lengthening group (1.5 months/cm). No case of neurovascular impairment was found in both groups.

The prognostic significance of 13q14 deletions in chronic lymphocytic leukemia

Although chronic lymphocytic leukemia (CLL) is the most common leukemia in adults, little is known about the molecular abnormalities underlying it and their prognostic significance. Using a battery of six microsatellite markers from 13q12.3-14.3 between BRACA2 gene and the Rb gene, we assayed loss of heterozygosity (LOH) in 78 CLL patients. We found deletion in 13q14 in 29 patients (37%) between D13S153 and the AFMa 301wb5. Classical cytogenetics was less sensitive, as it detected the 13q14 deletion in only one out of 69 patients (1%) in whom adequate metaphases were obtained. We found no significant difference in survival between patients with and patients without 13q14 LOH. In subset of patients with low beta2-microglobulin levels, those with 13q14 LOH had significantly shorter survival than did patients with low beta2-microglobulin levels but no 13q14 LOH. Also patients in early Rai stages (0-II) with 13q14 LOH had shorter survival period (P = 0.05) than did patients without LOH. These data confirm the prevalence of 13q14 deletion in CLL and suggest that this deletion may help identify more aggressive disease in patients presenting with early stage disease.

The influence of propolis ethanol extract on liver microsomal enzymes and glutathione after chronic alcohol administration

Propolis designates a series of gums, resins and balms of viscous consistency, which are gathered by honeybees from certain parts, mainly the buds and barks of plants, especially those found on coniferous trees. Bees bring propolis back to the hive, where it is modified and mixed with other substances including the bees' own wax and salivary secretions. In this study, the influences of propolis ethanol extract on chronic alcohol induced liver microsomal enzyme changes were investigated. Three grams of alcohol was added to rats' daily diet for four weeks to induce chronic alcohol liver injuries, and two different doses of propolis ethanol extract were p.o. administrated three times per day on the 28th, 29th, and 30th day. During the period of propolis administration, the ethanol diet was continued. After sacrifice, the rat livers were excised for assay of microsomal enzymes activity, glutathione (GSH) concentration, glutathione-S-transferase (GSTase) and gamma-glutamylcysteine synthetase (gamma-GCSase) activity. It was found that 30 mg/kg of propolis ethanol extract significantly prevented the elevations of total cytochrome P-450 enzymes, NADPH-dependent cytochrome C reductase, aniline hydroxylation, 7-ethoxyresorufin hydroxylation (7-ERH), 7-penthoxyresorufin hydroxylation (7-PRH), and lipid peroxidation induced by chronic ethanol administration. Additionally, propolis ethanol extract (100 mg/kg) also induced GSTase and gamma-GCSase activities and decreased glutathione levels in the liver.

Serum levels of insulin-like growth factor (IGF)-I, free IGF-I, IGF binding protein (IGFBP)-1, IGFBP-3 and insulin in obese children

In simple obesity, spontaneous and stimulated growth hormone (GH) secretions are diminished. However, this diminished GH secretion does not result in decreased somatic growth in obese children. Although the increased insulin level, low insulin-like growth factor binding protein (IGFBP)-1 and the resulting increase of bioavailability of insulin-like growth factor I (IGF-I) have been suggested as being involved, the exact mechanism has not yet been established. We investigated serum IGF-I, free IGF-I, IGFBP-1, IGFBP-3 and insulin levels in 36 obese and 39 non-obese healthy children. Insulin and IGFBP-3 were significantly higher in the obese group than in the control group (p < 0.05, p = 0.001, respectively). IGF-I, free IGF-I, free IGF-I/IGF-I and IGFBP-1 levels in the obese children were not significantly different from those in the control group. A positive correlation was found between body mass index (BMI) and IGF-I in the obese children (r = 0.30, p = 0.05). IGFBP-3 levels correlated positively with IGF-I (r = 0.44, p < 0.005), and free IGF-I levels (r = 0.37, p = 0.05) in the obese children. A negative correlation was found between IGFBP-1 and insulin levels (r = -0.30, p = 0.05) in the obese children. We concluded that normal growth in obese children might be maintained through normal IGF-I and increased IGFBP-3 levels, which are stimulated by increased insulin levels or nutritional factors or by increased responsiveness to GH.

Acute and chronic arsenic poisoning associated with treatment of acute promyelocytic leukaemia

Seven relapsed and/or refractory acute promyelocytic leukaemia patients were treated by arsenic trioxide (As2O3). Four patients (4/7, 57%) achieved complete remission after one to three cycles of treatment and the most common acute side-effect was fluid retention (in six patients, 86%), including weight gains and pleuro-pericardial effusions. Evident polyneuropathy compatible with chronic arsenic toxicity was noted in two of the three patients who received As2O3 maintenance therapy and one of them had marked distal muscular atrophy. We suggest that As2O3 may be a useful salvage therapy for relapsed and refractory APL patients, but the acute or chronic arsenic toxicity should be carefully monitored.

A novel, putative MEK kinase controls developmental timing and spatial patterning in Dictyostelium and is regulated by ubiquitin-mediated protein degradation

We have identified a developmentally regulated, putative MEK kinase (MEKKalpha) that contains an F-box and WD40 repeats and plays a complex role in regulating cell-type differentiation and spatial patterning. Cells deficient in MEKKalpha develop precociously and exhibit abnormal cell-type patterning with an increase in one of the prestalk compartments (pstO), a concomitant reduction in the prespore domain, and a loss of the sharp compartment boundaries, resulting in overlapping prestalk and prespore domains. Overexpression of MEKKalpha or MEKKalpha lacking the WD40 repeats results in very delayed development and a severe loss of compartment boundaries. Prespore and prestalk cells are interspersed throughout the slug. Analysis of chimeric organisms suggests that MEKKalpha function is required for the proper induction and maintenance of prespore cell differentiation. We show that the WD40 repeats target MEKKalpha to the cortical region of the cell, whereas the F-box/WD40 repeats direct ubiquitin-mediated MEKKalpha degradation. We identify a UBC and a UBP (ubiquitin hydrolase) that interact with the F-box/WD40 repeats. Our findings indicate that cells lacking the ubiquitin hydrolase have phenotypes similar to those of MEKKalpha null (mekkalpha-) cells, further supporting a direct genetic and biochemical interaction between MEKKalpha, the UBC, and the UBP. We demonstrate that UBC and UBP differentially control MEKKalpha ubiquitination/deubiquitination and degradation through the F-box/WD40 repeats in a cell-type-specific and temporally regulated manner. Our results represent a novel mechanism that includes targeted protein degradation by which MAP kinase cascade components can be controlled. More importantly, our findings suggest a new paradigm of spatial and temporal control of the kinase activity controlling spatial patterning during multicellular development, which parallels the temporally regulated degradation of proteins required for cell-cycle progression.

Simultaneous endoluminal sonography and manometry to assess anal sphincter complex in normal subjects

The purpose of this study was to use simultaneous anal manometry and high-frequency endoluminal ultrasonography (EUS) to determine the relationship between resting anal pressure and cross-sectional area of the internal and external anal sphincters. Eleven normal subjects underwent simultaneous anal EUS and manometry using catheters containing both pressure ports and ultrasound transducers. Resting pressure and cross-sectional area of the sphincters were made throughout the anal sphincter complex. The length of the internal anal sphincter (IAS) by sonography (27+/-5 mm) was significantly less than the length of the high pressure zone (HPZ) by manometry (44+/-8 mm; P < 0.001). Maximum IAS cross-sectional area (CSA) occurred 10+/-6 mm proximal to the peak resting pressure. The resting anal pressure correlated with external anal sphincter (EAS) CSA (r = 0.77), but not with IAS CSA (r = -0.17). The sum of EAS CSA and IAS CSA correlated strongly with resting pressure (r = 0.85). In conclusion, the IAS is shorter than the HPZ, with a significant distance separating maximum IAS CSA from peak resting pressure. The sum of the IAS and EAS CSAs, but not that of the IAS alone, correlated with resting pressure. Thus, this study suggests that the EAS, in addition to the IAS, contributes to resting anal pressure.

Cell death by apoptosis in the neonatal mouse cerebellum following gamma-irradiation

We have studied, by a nonisotopic in situ DNA end-labeling (ISEL) technique, the frequency of apoptosis in the external granular layer (EGL) of the cerebellum after whole-body irradiation of newborn mice by gamma-rays from 60Co. The total number of normal cells and cells showing morphological features of apoptosis were counted. The frequency of apoptotic cells was expressed as a percentage of the total number of cells in EGL. The extent of changes following 2 Gy (10.9 Gy/min) was studied at 2, 4, 6, 8, 12, or 24 hours after exposure. The maximal frequency was found 6-8 hours after exposure. Newborn mice that received 0.18, 0.36, 0.54, 1.08, 1.98, or 3.96 Gy were examined 6 hours after irradiation. Measurements performed after irradiation showed a dose-related increase in apoptotic cells in each of the mice studied. The dose-response curves were analyzed by a linear- quadratic model; frequency was (13.49 +/- 1.175) D + (-1.52 +/- 0.334) D2 +/- 0.048 (r2 = 0.981, D = dose in Gy). It provides the basis required for a better understanding of results which will be obtained in any further studies for biological responses of radiation using newborn orfetal mice.

Benign nonpeptic esophageal strictures. Diagnosis and treatment

This article studies the causes and treatment of benign nonpeptic esophageal strictures. The authors also discuss various therapeutic techniques for esophageal strictures, including esophageal dilatation with various dilators and balloons. Although the goals of stricture therapy are to relieve dysphagia and prevent stricture reoccurrence, only the first of these goals (effective dilatation with bougienage or balloon dilatation) has been achieved. The prevention of stricture reoccurrence remains to be achieved.

Human immunodeficiency virus infection in haemophiliacs in Taiwan: the importance of CD4 lymphocyte count in the progression to acquired immunodeficiency syndrome

From July 1984 to December 1996, we tested and studied 303 haemophilic patients for the infection of the human immunodeficiency virus (HIV). Among the 261 haemophilia A patients 44 were HIV positive (16.9%), while none of the haemophilia B patients was HIV positive. The mean age of the 44 HIV-seropositive patients in 1984 was 20.6 years (2-37 years). Seven who had known seroconversion dates and 29 whose first seropositive dates were known seroconverted before 1986. Acquired immunodeficiency syndrome (AIDS) has developed in 16 patients, nine of whom presented with Pneumocystis carinii pneumonia, three with tuberculosis infection, and 13 had died. The Kaplan-Meier estimate of the progression rate to AIDS after the date of first seropositive test is about 30% at the 10th year. The median survival time after development of AIDS obtained from the Kaplan-Meier estimate of the survival curve was 11.7 months. Statistical analysis for the covariate effects on the risk of developing AIDS by the Cox proportional hazards model revealed that there was a statistically significant negative association of the risk for progression to AIDS with the logarithm of initial CD4 cell counts (P = 0.027) and the rate of decline of CD4 cell counts (P = 0.040), but not with age (P = 0.650). In conclusion, the clinical characteristics of AIDS haemophiliacs in Taiwan were not different from that observed in western countries. Low initial CD4 cell count and sharp decline in CD4 cell counts, but not age, increased the risk of progression to AIDS.

Changes in serum haptoglobin level after allergen challenge test in asthmatic children

Bronchial asthma is characterized by airway inflammation, which underlies the phenomenon of bronchial hyperresponsiveness. Previous studies have shown that this correlates with the serum concentration of haptoglobin. The occurrence of the late asthmatic response (LAR) after an allergen challenge test is associated with airway inflammation. The objectives of this study were to examine serum levels of haptoglobin during the 24 h after allergen challenge and to compare changes between the subjects with and without LAR. We studied two groups of children with perennial asthma who developed the early asthmatic response (EAR) only (group I: n = 14), and EAR but also LAR (group II: n = 14) after an allergen (Dermatophagoides pteronyssinus) challenge test. Serum concentrations of haptoglobin were measured at baseline, at EAR, and at 2 h (recovery), 8 h (LAR), and 24 h after the challenge. Baseline levels were similar in the two groups (group I: 128 +/- 57 mg/dl; group II: 129 +/- 50 mg/dl). In group I, there was no significant change in the level at any time point; in contrast, the subjects in group II showed a relative fall (92 +/- 40 mg/dl) at 8 h, and an increase (161 +/- 79 mg/dl) at 24 h after the challenge. Our results indicate that the serum concentration of haptoglobin decreases at the time of LAR and is subsequently replenished during the ensuing time. Although further studies are needed, we think that haptoglobin may be inflused into the airways during the inflammatory process associated with LAR, and that this may be followed by "overshooting" production.

The hepatoprotective and therapeutic effects of propolis ethanol extract on chronic alcohol-induced liver injuries

Propolis designates a mixture of gums, resins and balms, of viscous consistency, which are gathered on certain parts (buds and bark, mainly) of vegetables (especially coniferous trees) by honeybees. They bring this back to the hive, where it is modified and mixed with other substances (essentially their own wax and salivary secretions). In this study, the hepatoprotective and therapeutic effects of propolis ethanol extract on chronic alcohol-induced liver injuries were investigated in rats. 3.125 ml of 99.5% alcohol was added to animal's daily diet for four weeks to induce chronic alcohol liver injuries. After sacrifice, serum transaminases (GOT, GPT), triacylglyceride and hepatic triacylglyceride (HTG) concentration were assayed to observe liver injuries induced by chronic alcohol abuse. In addition, the phenomenon of alcohol induced fatty liver were also observed by histopathological changes. Different doses of propolis ethanol extract were p.o. administered three times per day for three days, after four weeks' alcohol administration. It was found that 10 mg/kg of propolis ethanol extract significantly decreased the elevations of serum GOT, GPT, TG and HTG. In histopathological examination, 30 mg/kg of propolis ethanol extract also remarkably decreased the hepatocellular fatty degeneration, apparent as vacuolization, induced by chronic alcohol abuse.

Glycosaminoglycans modulate fibronectin matrix assembly and are essential for matrix incorporation of tenascin-C

We have investigated the role of glycosaminoglycans in fibronectin matrix assembly and the incorporation of tenascin-C into matrix fibrils. Chinese hamster ovary cell mutants with a total block in heparan and chondroitin sulfate production failed to assemble a fibronectin matrix, and incorporated no tenascin-C. Another mutant with reduced heparan sulfate produced a normal fibronectin matrix but failed to incorporate tenascin-C. Excess soluble glycosaminoglycans inhibited the binding of tenascin-C to purified fibronectin in ELISA, and completely blocked incorporation into matrix fibrils. Treating cultured cells with xyloside, which interferes with glycosaminoglycan attachment to proteoglycans, also completely blocked their ability to incorporate tenascin-C into matrix fibrils. We conclude that proteoglycans bound to fibronectin fibrils play a major role in binding tenascin-C to these fibrils. We examined more closely the large heparan sulfate proteoglycan, perlecan, and found that it co-localizes with tenascin-C and fibronectin in the matrix. The perlecan binding site in tenascin-C was mapped to the fibronectin type III domains 3–5, but this binding was strongly enhanced for the small splice variant, which is the major form incorporated into the matrix. Apparently when the alternative splice segment is inserted after domain 5 it inhibits perlecan binding. Thus heparan sulfate glycosaminoglycans, and perlecan in particular, may play a role in incorporation of the small splice variant of tenascin-C into fibronectin matrix fibrils.

Fixed pelvic obliquity after poliomyelitis: classification and management

We classified fixed pelvic obliquity in patients after poliomyelitis into two major types according to the level of the pelvis relative to the short leg. Each type was then divided into four subtypes according to the direction and severity of the scoliosis. In 46 patients with type-I deformity the pelvis was lower and in nine with type II it was higher on the short-leg side. Subtype-A deformity was a straight spine with a compensatory angulation at the lower lumbar level, mainly at L4-L5, subtype B was a mild scoliosis with the convexity to the short-leg side, subtype C was a mild scoliosis with the convexity opposite the short-leg side, and subtype D was a moderate to severe paralytic scoliosis with the convexity to the short-leg side in type I and to the opposite side in type II. A combination of surgical procedures improved the obliquity in most patients. These included lumbodorsal fasciotomy, abductor fasciotomy and stabilisation of the hip by triple innominate osteotomy with or without transiliac lengthening. In patients with type ID or type IID appropriate spinal fusion was usually necessary.

Effect of the distraction rate on the activity of the osteoblast lineage in distraction osteogenesis of rat's tibia. Immunostaining study of the proliferating cell nuclear antigen, osteocalcin, and transglutaminase C

The purpose of this study was to investigate kinetics of the osteoblast lineage in the periosteum and endosteum according to different distraction rates in distraction osteogenesis of rat's tibia. An osteotomy was performed on 144 rats at the proximal diaphysis of the left tibia. The lengthening process was started after a latency period of 3 days, with varying distraction rates of 0.25 mm (group I), 0.5 mm (group II), 0.75 mm (group III), 1.0 mm (group IV) and proceeded until a 3.5 mm length gain was achieved. The animals that had an osteotomy alone, without lengthening, served as a control (group V). Immunohistochemical staining of proliferating cell nuclear antigen (PCNA), osteocalcin, and transglutaminase C (TGase C) were done on the four animals in each group sacrificed at post-distraction days 1, 3, 5, 7, 14, and 28 in order to observe the temporal changes among the experimental and control groups. Also, in order to compare the staining rates at a given length gain among the groups, animals in each group were additionally sacrificed 2 days post-distraction in group II; 2 and 4 days in group III; and 1.5, 2 and 2.5 days in group IV. The results of the expression rates of PCNA, osteocalcin, and TGase C in each group were analyzed quantitatively. The immunohistochemical study on callotasis of rat's tibia revealed that the osteoblast lineage in the periosteum is more activated than that in the endosteum for proliferation and differentiation by distraction, suggesting that the periosteum plays a more important role in neoosteogenesis in the distraction gap. Daily distraction rates ranging from 0.25 mm to 0.75 mm in two increments is appropriate for successful distraction osteogenesis of rat's tibia, but the rate of 0.25 mm a day is significantly better than that of 0.75 mm as was made evident in the immunohistochemical observations.

Intussusception associated with Yersinia pseudotuberculosis infection

Intussusception associated with Yersinia pseudotuberculosis infection was developed in three boys; two of them had a history of drinking untreated water. All intussusceptions were localized at the ileocolic region, and all patients completely recovered with Gastrografin enema and supportive treatment without complication and operation.

Acute renal failure associated with Yersinia pseudotuberculosis infection in children

We report 45 pediatric cases of Yersinia pseudotuberculosis infection confirmed by stool culture between May 1993 and June 1994. In 41 (91.1%) cases there had been contact with untreated well or mountain water. Y. pseudotuberculosis was also isolated from 4 samples of mountain spring water thought to be the sources of infection. During the course of the illness, acute renal failure (ARF) developed in 6 patients (13.6%). The age distribution of the ARF group (12.3 +/- 1.2 years) was significantly different from the non-ARF group (8.0 +/- 3.2 years). The serogroups of Y. pseudotuberculosis isolates from stool samples were 5 (n = 30) and 4 (n = 15). Isolates from the water samples were all serogroup 5. The main symptoms of both groups were fever, rash, abdominal pain, and vomiting. ARF developed between the 2nd and 14th days (mean 6 days) after the onset of fever, and oliguria (< 400 ml/m2 per day) developed in 3 patients (3/6, 50%) immediately after their fevers had subsided. ARF underwent a benign course, with complete recovery within a maximum of 4 weeks (mean 10.2 days), with 1 exceptional patient requiring hemodialysis. Renal biopsy showed evidence of tubulointerstitial nephritis. Y. pseudotuberculosis should be included as one of the causes of acute interstitial nephritis causing ARF in children, especially when the children have histories of drinking untreated water in endemic areas.

[The influence of job characteristics and workplace subculture on individuals' drinking behavior--an exploratory pilot study]

The purpose of this study was to explore how individuals' drinking behavior was associated with their jobs in terms of the amount consumed and its consequences. The researchers attempted to analyze the characteristics of job and workplace from structural, psychological, and cultural perspectives. The structural dimension referred to years serving in a company, years serving in a department, work position, work characteristics, and shift. The psychological dimension was addressed on perceived stress and work hazards. The cultural dimension of one's job consisted of formal and informal norms regarding one's drinking within the workplace. The result showed the occurrence of drinking-related problems was significantly associated with workplace subculture among the non-aboriginal Chinese males. However, none of the three perspectives as job characteristics was significantly associated with drinking amount. The findings imply that the workplace subculture plays a determinant role in affecting individual's drinking behavior, moreover, it could result in one's problem drinking.

Mitogenesis, cell migration, and loss of focal adhesions induced by tenascin-C interacting with its cell surface receptor, annexin II

In a previous study we demonstrated that the alternatively spliced region of tenascin-C, TNfnA-D, bound with high affinity to a cell surface receptor, annexin II. In the present study we demonstrate three changes in cellular activity that are produced by adding intact tenascin-C or TNfnA-D to cells, and we show that all three activities are blocked by antibodies against annexin II. 1) TNfnA-D added to confluent endothelial cells induced loss of focal adhesions. 2) TNfnA-D produced a mitogenic response of confluent, growth-arrested endothelial cells in 1% serum. TNfnA-D stimulated mitogenesis only when it was added to cells before or during exposure to other mitogens, such as basic fibroblast growth factor or serum. Thus the effect of TNfnA-D seems to be to facilitate the subsequent response to growth factors. 3) TNfnA-D enhanced cell migration in a cell culture wound assay. Antibodies to annexin II blocked all three cellular responses to TNfnA-D. These data show that annexin II receptors on endothelial cells mediate several cell regulatory functions attributed to tenascin-C, potentially through modulation of intracellular signalling pathways.

Binding of tenascin-C to soluble fibronectin and matrix fibrils

The small splice variant of tenascin-C (TN) has eight fibronectin type III (FN3) domains. The major large splice variant has three (in chicken) or seven (in human) additional FN3 domains inserted between domains five and six. Chiquet-Ehrismann et al. (Chiquet-Ehrismann, R., Matsuoka, Y., Hofer, U., Spring, J., Bernasconi, C., and Chiquet, M. (1991, Cell Regul. 2, 927-938) demonstrated that the small variant bound preferentially to fibronectin in enzyme-linked immunosorbent assay, and only the small variant was incorporated into the matrix by cultures of chicken fibroblasts. Here we have studied human TN, and confirmed that the small variant binds preferentially to purified fibronectin and to fibronectin-containing extracellular matrix. Thus this differential binding appears to be conserved across vertebrate species. Using bacterial expression proteins, we mapped the major binding site to the third FN3 domain of TN. Consistent with this mapping, a monoclonal antibody against an epitope in this domain did not stain TN segments bound to cell culture matrix fibrils. The enhanced binding of the small TN variant suggests the existence of another, weak binding site probably in FN3 domains 6-8, which is only positioned to bind fibronectin in the small splice variant. This binding of domains 6-8 may involve a third molecule present in matrix fibrils, as the enhanced binding of small TN was much more prominent to matrix fibrils than to purified fibronectin.

Efficacy of measles vaccine during the 1993 measles epidemic in Korea

Immunization to eliminate measles is recommended at 15 months of age with the option of giving vaccine at 6 to 9 months of age during measles outbreaks in Korea. Because of the recent resurgence of measles and concern about the possibility of reduced vaccine efficacy caused by genomic differences between vaccine virus and contemporary wild measles viruses, we conducted a measles vaccine efficacy study involving children with household exposure ages 1 to 5 years during measles outbreak that had occurred 1993 in Seoul and Seong-nam city, with the demographic analysis of patients brought to the hospitals. A total of 380 patients (M:F = 216:164) were included in this study. Two hundred nine cases (55.0%) occurred in children less than 5 years of age, and 167 (43.9%) were younger than 16 months of age. The recorded age-specific incidence rates showed bimodal patterns, i.e. highest peak in those below 16 months of age and second peak in those ages 6 to 9 years of age. Only 9.6% (16 of 167) of the measles cases less than 16 months, 59.5% (25 of 42) of those 16 months to 4 years and 91.8% (157 of 171) of the cases in school age children have been vaccinated. Attack rates among the 122 vaccinated siblings and 12 unvaccinated siblings ages 1 to 5 years who contacted measles were 5.7 and 75%, respectively, and the clinical vaccine efficacy was 92.4% (95% confidence interval, 83.6, 96.4). The high vaccine efficacy in household exposures suggests that measles outbreaks in Korea are not caused by reduced vaccine efficacy.

Polymerase chain reaction for identification of human and porcine spirochaetes recovered from cases of intestinal spirochaetosis

A polymerase chain reaction (PCR) amplification of 16S rDNA was developed to identify spirochaetes recovered from cases of intestinal spirochaetosis in humans and pigs; these bacteria belong to a distinct genetic group of spirochaetes, with the proposed name 'Anguillina coli'. The PCR incorporated a universal eubacterial 16S rDNA sequencing primer (1492r), and a 21-base forward primer designed to include a nucleotide sequence specific for 'A. coli'. The PCR was used to correctly identify DNA extracted from 43 isolates of 'A. coli' from humans and pigs, whilst no product was produced from Escherichia coli, or from other intestinal spirochaetes, including 38 isolates of Serpulina spp., and one each of Treponema succinifaciens and Brachyspira aalborgi. The amplification provided a rapid and simple means of identifying DNA from isolates of 'A. coli', and could be used on boiled whole 'A. coli' cells, with a detection limit equivalent to 2.5 x 10(2) cells. The reaction was used to detect and identify these spirochaetes from selective agar plates inoculated with stool specimens from infected pigs.

Acquired vitamin D-resistant rickets caused by aggressive osteoblastoma in the pelvis: a case report with ten years' follow-up and review of the literature

Rickets or osteomalacia secondary to tumor in either bone or soft tissue is rare and interesting in that it can be cured after removal of the tumor. The majority of the reported cases occurred in adults older than 30 years, and the most commonly associated types were vascular and fibrous tumors. We present a new case of aggressive osteoblastoma in the ilium, which induced vitamin D-resistant rickets in an 8-year, 9-month-old boy. Radiographs and blood chemistry findings on admission showed typical features of active hypophosphatemic ricketts. He underwent three local excisions of the tumor. At 10-year follow-up, the patient was symptom free but short. When a child has symptoms of rickets that develop relatively later than ordinary vitamin D-resistant rickets, every effort should be made to search out a tumorous lesion before attributing it to a renal origin.

Preoperative embolization in the treatment of spinal metastasis from renal cell carcinoma--a case report

Metastatic lesions due to renal cell carcinoma are frequently hypervascular. Surgical treatment of these lesions results in excessive operative blood loss. Bleeding may result in technical difficulties and complications during the operation. When surgical treatment of hypervascular spinal metastases is indicated, preoperative embolization, although technically demanding, has been effective in devascularizing these lesions and is an adjunct to internal fixation.

Cell surface annexin II is a high affinity receptor for the alternatively spliced segment of tenascin-C

We have investigated the binding of soluble tenascin-C (TN-C) to several cell lines using a radioligand binding assay. Specific binding was demonstrated to U-251MG human glioma cells and to a line of bovine aortic endothelial cells, but hamster fibroblasts showed no specific binding. Recombinant proteins corresponding to specific domains of TN-C were used to map the binding site(s) in TN-C. The alternatively spliced segment (TNfnA-D) inhibited the binding of native TN-C most strongly, and itself bound to glioma and endothelial cells. Scatchard analysis of TNfnA-D binding indicated 2-5 x 10(5) binding sites per cell, with an apparent 2 nM dissociation constant. The cell surface receptor for TNfnA-D was identified as a 35-kD protein on the basis of blot binding assays and affinity chromatography of membrane extracts on native TN-C and TNfnA-D columns. Protein sequencing indicated that this 35-kD receptor was annexin II. Annexin II is well characterized as a cytoplasmic protein, so it was surprising to find it as a presumably extracellular receptor for TN-C. To confirm that it was the 35-kD receptor, we obtained purified annexin II and demonstrated its binding to TNfnA-D and TN-C at nM concentrations. Antibodies to annexin II prominently stained the external surface of live endothelial cells and blocked the binding of TNfnA-D to the cells. Thus annexin II appears to be a receptor for the alternatively spliced segment of TN-C, and may mediate cellular responses to soluble TN-C in the extracellular matrix.

Effect of tibial lengthening on the gastrocnemius muscle. A histopathologic and morphometric study in rabbits

We observed the changes of the gastrocnemius muscle in relation to the percentage of lengthening of the rabbit's tibia by callotasis. 75 rabbits were separated into 3 lengthening groups, 10, 20, and 30 percent lengthening, respectively. Histopathologic observations, based on the fiber size variation, internalization of the nuclei, degeneration, regeneration, and endomysial fibrosis of muscle fibers, revealed that substantial changes occurred in the latter groups. Histomorphometrically, the decrease in the mean size of Types I and II muscle fibers was observed in all lengthening groups, but there was no significant change in the proportion of the muscle fiber types in any of the lengthening groups.

Longitudinal growth of the rabbit tibia after callotasis

We investigated the effect of bone lengthening by callotasis on longitudinal growth of the tibia in rabbits. Ninety-nine five-week-old immature rabbits were divided into five groups according to the percentage of lengthening: group I, 10%; group II, 20%; group III, 30%; group IV, 40%; and group V, sham operation without lengthening. Corticotomy was performed at the proximal metaphysis of the left tibia and the right tibia was used as a control. The lengthening rate was 0.25 mm twice daily. Radiological, histomorphometric, and immunohistochemical studies were done on animals killed at the time of corticotomy, at the completion of lengthening, and thereafter every two weeks until 12 weeks. Tibial lengthening did not cause retardation of growth when the bone was lengthened by up to 20%. When the bone was lengthened by 30% or more, growth retardation was evident, and persisted until skeletal maturity.

Triple innominate osteotomy for hip stabilisation and transiliac leg lengthening after poliomyelitis

We reviewed our experience with a modified triple innominate osteotomy for hip instability and limb shortening due to poliomyelitis in 62 adolescent and adult patients, treated from 1973 to 1990. Their ages at surgery ranged from 12 years to 35 years (average 22.3). At a mean follow-up of 4 years (2 to 18) 59 of the patients (95.2%) had substantial improvement in hip stability, and all but one had radiological improvement as determined by the acetabular angle, centre-edge angle and acetabulum-head quotient. In 59 cases in which transiliac limb lengthening was attempted, the mean gain was 1.7 cm (0.6 to 3.0). When the abductor muscles had been partially paralysed, the operation produced an appreciable increase in power in 12 of the 39 hips examined.

Endothelial cells adhere to the RGD domain and the fibrinogen-like terminal knob of tenascin

We have found that endothelial cells adhere much more strongly than fibroblasts to domains of tenascin and fibronectin. Endothelial cells adhered weakly, without spreading, to bacterial expression proteins corresponding to the tenth fibronectin type III (FN-III) domain of fibronectin, which contains the RGD. A larger fibronectin protein, containing this domain and the three amino-terminal ‘synergy’ domains gave strong adhesion and spreading. Two widely separated domains of tenascin gave adhesion. The third FN-III domain, TNfn3, which contains an RGD sequence in human and chicken tenascin, gave very strong adhesion and spreading of endothelial cells when tested as an isolated domain. Larger segments containing TNfn3 and the adjacent TNfn2 gave weaker adhesion, probably because the RGD sequence is partially blocked. Adhesion to this domain required divalent cations, was exquisitely sensitive to soluble GRGDSP peptide, and was blocked by antisera to the integrin alpha v beta 3. The second tenascin adhesion domain was the fibrinogen-like C-terminal knob, TNfbg. Cells adhered to but did not spread on this domain. This adhesion required divalent cations and was also sensitive to GRGDSP peptide, so it may be mediated by an integrin receptor. We have explored a range of conditions for preparing the adhesion substratum, and our results may resolve the controversy over whether tenascin can act as a substratum adhesion molecule. When coated for short times (1-2 hours) on plastic, tenascin had no adhesion activity, in contrast to fibronectin and the expression proteins, which gave strong adhesion under these conditions. When coated for longer times (12-24 hours) on plastic, the tenascin substratum supported good adhesion, but not spreading, of endothelial cells. Tenascin coated on nitrocellulose gave substantially stronger adhesion than on plastic, but still required long coating times for maximal activity. Adhesion of endothelial cells to native TN was inhibited by GRDGSP peptide. The cell adhesion activity demonstrates the presence on endothelial cells of tenascin receptors, which may play a supportive role in angiogenesis, in the structure of blood vessels, or in binding tenascin to the cell surface to elicit or enhance a signalling function.

A modified Wagner technique for femoral lengthening in skeletally mature patients with poliomyelitis

A modified Wagner technique using an Orthofix was employed for femoral lengthening in 62 skeletally mature patients with residual poliomyelitis. The first stage was similar to that of the original Wagner technique. However, distraction was started after 5 to 7 days at a rate of 1.5 mm per day. At the second stage, a neutralization plate was applied and a corticocancellous iliac strut graft inserted in the distracted site, preferably under compression. Cast immobilisation was not used and a long leg brace with a thigh corset allowed early knee movement and weightbearing. The average age at operation was 26 years and 6 months. The period of follow-up averaged 3 years and 2 months, and the average amount of lengthening was 4.2 cm. The overall rate of complication was 34%.

Neutralizing monoclonal antibody epitopes of the Entamoeba histolytica galactose adhesin map to the cysteine-rich extracellular domain of the 170-kilodalton subunit

Entamoeba histolytica adheres to human colonic mucins and colonic epithelial cells via a galactose-binding adhesin. The adhesin is a heterodimeric glycoprotein composed of 170- and 35-kDa subunits. Fragments of the hgl1 gene encoding the 170-kDa subunit were expressed as recombinant fusion proteins in Escherichia coli and reacted with anti-adhesin monoclonal antibodies (MAbs) or pooled human immune sera. The MAbs tested recognize seven distinct epitopes on the 170-kDa subunit and have distinct effects on the adherence and complement-inhibitory activities of the adhesin. All seven MAbs reacted with a fusion protein containing the cysteine-rich domain of the protein. Pooled human immune sera reacted with the same cysteine-rich domain as the MAbs and also with a construct containing the first 596 amino acids. Reactivity of three MAbs with the surface of intact trophozoites confirmed that the cysteine-rich domain was located extracellularly. The location of individual epitopes was fine mapped by constructing carboxy-terminal deletions in the cysteine-rich region of the fusion protein. The locations of adherence-enhancing and -inhibiting epitopes were partially distinguished, and the epitopes where complement-inhibitory MAbs bound were demonstrated to be near the adhesin's area of sequence identity with the human complement inhibitor CD59.

Changes of blood flow of the femoral head after subtrochanteric osteotomy in Legg-Perthes' disease: a serial scintigraphic study

Serial quantitative scintigraphic studies using 99mTc-methylene diphosphonate were performed on 25 hips with Legg-Perthes' disease to evaluate changes in local blood flow of the femoral head after subtrochanteric varizational and/or derotational osteotomy. Studies were made preoperatively and were repeated postoperatively at 2, 4, 6, and 8 weeks at 3 and 6 months, at 1 year, and finally at 2 years after osteotomy. The relative vascularity of the affected femoral head at 2 weeks after osteotomy was significantly decreased as compared with the preoperative value. Thereafter, it increased steadily, reaching the preoperative level by 6 months with no further statistically significant increase at < or = 2 years. Our scintigraphic study showed that local blood flow of the femoral head does not increase significantly after subtrochanteric femoral osteotomy in Legg-Perthes' disease.