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Antibody-binding to the 180-kD bullous pemphigoid antigens at the lateral cell surface causes their internalization and inhibits their assembly at the basal cell surface in cultured keratinocytes.

We demonstrated the effects of monoclonal antibodies to the 180-kD and 230-kD BP antigens (BPA) and of BP sera on Ca(++)-induced formation of hemidesmosomes in cultured human keratinocytes (a cell line, DJM-1) by immunofluorescence microscopy. Under low Ca++ (0.07 mM) conditions, the 180-kD and 230-kD BPAs were distributed homogeneously on the basal plasma membrane, while they formed a peculiar concentric ring or arch (ring/arch) arrangement in high-Ca++ (1.87 mM) medium. On the other hand, the apical-lateral cell membrane was stained homogeneously with antibodies to the 180-kD BPA, but not to the 230-kD BPA, both in low and high Ca++ media. The low-high Ca++ switch at first caused disappearance of the antigen from the basal plasma membrane and then formed the high-Ca++ ring/arch pattern within 3 hrs. In this system, monoclonal antibodies to the 180-kD and 230-kD BPAs and the sera from 5 BP patients, 2 pemphigus vulgaris (PV) patients, and 4 normal volunteers were added into the culture media. The addition of anti-180-kD BPA antibodies or any BP serum caused the internalization of the 180-kD BPA from the apical-lateral cell membrane and inhibited the Ca(++)-induced formation of the ring/arch pattern on the basal membrane, possibly by inhibiting the movement of the antigen from the lateral to the basal membrane to form hemidesmosomes.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Monoclonal↗

Myosin heavy chain messenger RNA from myogenic cell cultures.

The appearance of messenger RNA for myosin heavy chains in chick-embryo myogenic cell cultures was investigated. Total polyribosomes were isolated from cultures at various times of development and were purified in sucrose step gradients. These polysomes were either extracted with phenol or were treated with puromycin. The ribonucleoprotein particles and ribosomal subunits released by puromycin were fractionated on sucrose gradients. RNA from polysomes or from puromycin-dissociated subunits was fractionated on oligo(dT)-cellulose columns, and the bound and unbound RNA was assayed for activity of myosin heavy chain messenger RNA in a rabbit reticulocyte cell-free system. RNA stimulating myosin heavy-chain synthesis was found predominantly in the unbound fractions of the oligo(dT)-cellulose columns. After puromycin treatment of polysomes, the myosin heavy chain messenger RNA, which sediments at 18-26 S, was associated with a ribonucleoprotein particle sedimenting between 30 and 40 S. Myosin heavy chain messenger RNA was obtained from cultures containing well-developed myotubes and from cultures undergoing myogenic cell fusion. This messenger RNA was not detectable in early, unfused cultures, or in later cultures in which myogenic cell fusion had been prevented by treatment with ethyleneglycol bis(beta-aminoethyl ether)-N,N'-tetraacetic acid. These experiments demonstrate that messenger RNA for myosin heavy chains becomes associated with ribosomes only after myogenic cell fusion has begun.

Acetates↗

The spatial organization of the peripheral olfactory system of the hamster. Part II: Receptor surfaces and odorant passageways within the nasal cavity.

The spatial organization of olfactory receptor surfaces and odorant passageways within the nasal cavity was studied in hamsters through descriptive and morphometric analyses of a complete stereotaxically defined series of coronal, sagittal, and horizontal sections through the snout. These analyses reveal that the caudal two-thirds of each cavity is divided into two longitudinally oriented medial and lateral channels. The olfactory mucosa that lines these two channels projects selectively onto the medial and lateral halves of the main olfactory bulb (MOB), respectively. Moreover, the ethmoturbinates of the caudal recesses create highly convoluted channels, lined by ventrally projecting mucosa, that lie ventral, lateral, and dorsal to a relatively smooth central channel lined by dorsally projecting mucosa. The rhinotopic map makes equivalent representations of medial and lateral olfactory space to the MOB but gives the smooth space lined by dorsally projecting mucosa a disproportionately larger representation on the MOB than the convoluted space lined by the more expansive ventrally projecting mucosa. Recent descriptions of the spatial distribution of probes for odorant receptor proteins conform closely to this organization, giving credence to the idea that rhinotopy is a basis for representing to the MOB the specific molecular features of odorant molecules.

Animals↗

Factors influencing early poult flip-overs in experimental populations of turkeys.

A large number of poults from a line (E) selected long-term for increased egg production were observed, in recent generations, to flip over during the week immediately after hatching. This condition, termed early poult flip-overs (EPF), is characterized by the poults falling on their back and being unable to right themselves without assistance. Poults that flip over more than once appear to lack neurological control, lying on their backs with their legs paddling. If handled, the affected poult moves its head laterally and after several seconds appears to go to sleep. When placed on litter, the poult has no sense of balance and falls to one side or the other and starts paddling its feet. Poults that flip over may also chirp loudly. Observations from previous years indicate that no bacterial infectious agent was associated with the EPF condition. Affected poults have increased mortality relative to normal poults that do not flip over. The objective of the present study was to evaluate the effects of inheritance, beak trimming, hatching time, genetic growth potential, and poult hydration on the incidence of EPF. The E line had a greater incidence of EPF than its randombred control line, indicating the possibility of a genetic basis for the condition. However, within the E line, the heritability, based on variation among full-sib families, of the occurrence of EPF (assuming that EPF is an all-or-none trait) was low, being 0.044 and 0.052 in 2 consecutive yr. The heritability of the number of days (out of five) a poult continued to flip over was somewhat higher [0.26+/-0.002 (SE)]. Genetic growth potential may influence incidence of EPF for, when the E line was crossed with a large-bodied experimental line selected for increased 16-wk BW, the frequency of EPF was reduced and BW at 13 d of age was increased in the cross relative to the pure E line even though poult weight was similar at hatching in the two genetic groups. In the E line, later hatching poults within a hatch had a greater incidence of EPF than those hatching earlier. Neither beak trimming with an electronic beak trimmer nor poult hydration influenced EPF.

Animal Husbandry↗

Visual input and lateralization of brain function in learning in the chick.

Several lines of evidence (biochemical, neuroanatomical, electrophysiological, and behavioural) have indicated a critical role for the intermediate medial hyperstriatum ventrale of the chick forebrain in the acquisition of a passive avoidance response. Previous lesion studies indicated that bilateral or left, but not right, pretraining intermediate medial hyperstriatum ventrale lesions interfere with the acquisition of this task. We have further analysed this asymmetrical involvement of the intermediate medial hyperstriatum ventrale by use of a monocular learning protocol and intermediate medial hyperstriatum ventrale lesions (sham, bilateral, or unilateral). The results indicated that there is interocular transfer of information of passive avoidance learning between the two eye systems, with a tendency to be more successful from the right eye system to the left than in the opposite direction. As in binocular conditions, bilateral pretraining intermediate medial hyperstriatum ventrale lesions impair learning in monocularly trained animals. Unilateral lesions to either left or right monocularly trained experimental animals resulted in amnesia when they were made to the right intermediate medial hyperstriatum ventrale and the chicks were trained/tested with the left eye open. These results indicate that, although right intermediate medial hyperstriatum ventrale lesions do not result in amnesia in binocular animals, this region is capable of participating in memory acquisition processes. They also suggest a connection between lateralization of intermediate medial hyperstriatum ventrale function in passive avoidance learning and the behavioural and structural visual asymmetries known to occur in chicks.

Animals↗

GDNF selectively protects dopamine neurons over serotonin neurons against the neurotoxic effects of methamphetamine.

Repeated methamphetamine (METH) administration to animals can result in long-lasting decreases in striatal dopamine (DA) and serotonin (5-HT) levels. Glial cell line-derived neurotrophic factor (GDNF) has pronounced effects on dopaminergic systems in vivo, including partial neuroprotective effects against 6-hydroxydopamine and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine -induced lesions. The present study examined the ability of GDNF to prevent METH-induced reductions in potassium-evoked overflow of DA, and DA and 5-HT content, in striatum. GDNF (10 microg) or vehicle was injected into the right striatum of anesthetized rats. Twenty-four hours later, the rats were injected four times at 2 hr intervals with METH (5 mg/kg, s.c.) or saline. One week later, in vivo electrochemistry was used to monitor the overflow of DA evoked by local potassium application. Evoked overflow of DA was dramatically decreased in the striatum of METH-treated animals. GDNF prevented the reduction in evoked overflow of DA in the right striatum of the METH-treated animals. After each experiment, the animals were killed, and striatal DA and 5-HT levels determined by HPLC. The METH treatment produced significant decreases in both neurotransmitters. GDNF administration prevented the reduction in striatal DA levels on the treated side of the brain, whereas levels on the contralateral side were still decreased. In dose-response studies, 1 microg of GDNF was as protective as 10 microg, whereas 0.1 microg was only partially protective. In contrast, 5-HT levels were only minimally protected by previous administration of GDNF. These results suggest that GDNF can selectively protect DA neurons, compared with 5-HT neurons, against the neurotoxic effects of METH.

Animals↗

Picture archiving and communication system in Hokkaido University Hospital: advantage and disadvantage of HU-PACS chest roentgenogram images in the outpatient clinic.

A new Hokkaido University picture archiving and communication system (HU-PACS) has been in clinical use in the outpatient clinic at HU Hospital. To evaluate the quality of the cathode-ray tube (CRT) monitor images, we compared the detectability of line shadows in the chest roentgenogram images on the CRT monitor with those on the computed radiography (CR) film. We randomized chest roentgenograms from 20 patients who were admitted to the outpatient clinic with pulmonary disease. Two physicians, whose speciality is chest roentgenogram diagnosis, checked whether they could recognize a horizontal fissure line (hairline) on the posteroanterior view and a minor fissure line and major fissure lines on the lateral view. Only 30% of hairlines were recognized on CRT monitor as compared with 65% on CR film. On the lateral view, only 68% of major fissures and 53% of minor fissures on CRT monitor were recognized as compared with 89% and 79%, respective on CR film. Furthermore, it was somewhat difficult to follow entire lines on some of the CRT monitor images. Clinically, the greatest advantage of the PACS is immediate availability of images, including chest roentgenogram, chest computed tomography (CT) and magnetic resonance imaging (MRI). PACS is also convenient for consulting colleagues in other departments. Unfortunately, the quality of the image on the CRT monitor is not yet good enough to visualize line shadows and small solitary lesions on the chest roentgenogram image. Recent advances in high technology have been so rapid, however, that higher resolution CRT monitors will be available soon.

Computer Terminals↗

Synergism of intraventricular NaCl infusion and subpressor angiotensins in rats.

The effect of selective salt infusion to the central nervous system on the blood pressure (BP) regulation was examined in male Wistar rats. Hypertonic NaCl (0.8 M, 1 microliter/h) was infused into the lateral ventricle concomitantly with intravenous infusion of a subpressor dose (5.4 pmol.kg-1.min-1) of angiotensin II (ANG II) or its analogues for 7 days using osmotic minipumps. The BP was not increased by intracerebroventricular infusion of NaCl alone at this dose but was significantly and consistently increased by concomitant intravenous infusion of ANG II or its analogues. The increases in the BP over the base-line values on day 7 in groups on infusions of ANG II, ANG III, and pentasarcosyl-ANG II [(Sar)5ANG II] were 29 +/- 5 mmHg (n = 9, P less than 0.05), 8 +/- 2 mmHg (n = 8, P less than 0.05), and 19 +/- 3 mmHg (n = 6, P less than 0.05), respectively. The responses to hexamethonium, prazosin, and antagonists of arginine vasopressin and ANG II were examined in separate sets of conscious and unrestrained animals that had received intracerebroventricular infusion of NaCl and intravenous infusion of ANG II for the preceding 6 days. These animals showed significantly greater depressor responses only to hexamethonium and prazosin than control. These results indicate that the pressor effect of continuous and concomitant administration of intracerebroventricular NaCl and intravenous ANG II is mainly due to activation of the sympathetic nerve function. Synergism of the effects of selective central sodium administration and a subpressor dose of ANG II in the central nervous system is suggested.

Angiotensins↗

Auditory brainstem anomalies in albino cats: II. Neuronal atrophy in the superior olive.

In a previous paper (Brain Res., 260:1-9, 1983) we reported that albino cats show abnormal auditory brainstem evoked responses that appear to arise from structural defects in or near the superior olivary complex. In the present study, neuronal cross-sectional area in brainstem nuclei was compared in albino and normally pigmented adult cats. The albinos were true tyrosinase-negative (cc) and should not be confused with the deaf white cat (W); the albinos are not deaf. Neurons in the medial superior olivary nucleus (MSO) of albinos were, on average, 41% smaller than in pigmented animals; there was no overlap in the neuronal size distributions for the two groups of animals. Cell size in the lateral superior olive, medial nucleus of the trapezoid body, ventral nucleus of the lateral lemniscus, anteroventral cochlear nucleus, dorsal cochlear nucleus, and facial nucleus was also smaller (by 9-21%) in albinos than in pigmented animals but none of these differences was statistically reliable. In the abducens nucleus, neurons were 12% larger in albinos than in pigmented animals, demonstrating that neuronal size in the albinos is not uniformly smaller. Several lines of evidence suggest that the auditory system defects in albinos are related to abnormal pigmentation rather than to other gene effects. It is possible that a subtle pigment-related disruption of inner ear development in albinos results in a central cascade of atrophic changes along the auditory pathway.

Animals↗

Angiogenesis from mononuclear cells in thrombi.

In organizing thrombi angiogenesis is not dependent on invasion of vasa vasora from the vascular wall. Mononuclear cells of the monohistiocytic system are always present within the clotted blood and are capable of differentiation into various types of mesenchymal cells, including endothelial cells. At first autolytic slits and clefts appear in the fibrinous superficial areas of the thrombus. They are gradually lined by spindle-shaped "pre-endothelial" cells that already possess immunohistological properties of endothelial cells but still resemble primitive mesenchymal cells ultrastructurally. Later these cells gain connection with each other by pseudopodia, overlapping and interdigitation until the channels in the fibrinous matrix are covered by an uninterrupted layer of cells. These cells are now characterized ultrastructurally by the appearance of specific endothelial organelles (Weibel-Palade bodies). Circulation within these channels begins from the blood stream. In addition, angiogenesis by sprouting of vasa vasora from the vascular wall occurs in those areas of the thrombus in contact with the vessel wall. In blood vessels with on unimpaired intimal layer, angiogenesis by invasion of capillaries occurs at an earlier date than capillary formation by mononuclear cells.

Adolescent↗

Zebrin II distinguishes the ampullary organ receptive map from the tuberous organ receptive maps during development in the teleost electrosensory lateral line lobe.

In weakly electric gymnotiform teleosts, monoclonal antibody anti-zebrin II recognizes developing pyramidal cells in the ampullary organ-receptive medial segment of the medullary electrosensory lateral line lobe (ELL) and in the mechanoreceptive nucleus medialis. Developing pyramidal cells in the remaining three tuberous organ-receptive lateral ELL segments are unreactive. These results suggest that certain biochemical features of the ELL ampullary organ-receptive medial segment are more similar to the nucleus medialis than to the tuberous organ-receptive ELL segments, and support the hypothesis that the ampullary system evolved from mechanosensory precursors.

Animals↗

Evaluation of novel modified tangential irradiation technique for breast cancer patients using dose-volume histograms.

PURPOSE: We have previously reported that entire axillary lymph node regions could be irradiated by the modified tangential irradiation technique (MTIT). In this study, MTIT was compared with a conventional irradiation technique (CTIT) using dose-volume histograms to verify how adequately MTIT covers the breast and axillary lymph node region and the extent to which it involves the lung and heart. METHODS AND MATERIALS: Forty-four patients with early-stage breast cancer were treated by lumpectomy, axillary dissection, and postoperative radiotherapy. Twenty-two patients were treated with MTIT and 22 with CTIT. In 25 patients, the breast tumor was on the left and in 19 on the right. During axillary dissection, surgical clips were left as markers at the border of the axillary lymph node region. MTIT was planned by setting the dorsal edge of the radiation field on a lateral-view simulator film at the dorsal edge of the humeral head and the cranial edge of the radiation field at the caudal edge of the humeral head. CTIT was planned to ensure radiation of the breast tissue without considering the axillary region. In this study, all patients underwent computed tomography, and the CT data were transmitted on-line to a radiotherapy planning system, in which the dose-distribution computed tomography images and dose-volume histograms were calculated by defining the breast, axillary region (levels I, II, and III), lung, and heart region. RESULTS: Dose-volume histogram analysis demonstrated that breast tissue was radiated with an 86.5-100% volume (median 96.5%) by MTIT and an 83-100% volume (median, 95%) by CTIT at >95% of the isocenter dose. The axillary lymph node regions at Levels I, II, and III were irradiated with 84-100% (median, 94.5%), 59-100% (median, 89%), and 70-100% (median, 89.5%) volumes, respectively, by MTIT and with 2-84% (median, 38%), 0-53% (median, 15%), and 0-31% (median, 0%) volumes, respectively, by CTIT at >70% of the isocenter dose. The ipsilateral lung was irradiated with a 5-22% volume (median, 11.5%) by MTIT and 5-15% volume (median 9%) by CTIT at >90% of the isocenter dose. In all 25 left-sided breast cancer patients, the volumes irradiated with an 80% isocenter dose were <30 cm(3). CONCLUSION: The results of our study demonstrated that the breast tissue was sufficiently irradiated with both CTIT and MTIT planning, the axillary lymph node areas irradiated by MTIT were much wider than those irradiated by CTIT at all levels, and the lung and heart volumes irradiated by MTIT were small.

Adult↗

Effect of plasmin on movement characteristics of ejaculated bull spermatozoa.

Proteolytic enzymes appear to have an essential role in multiple phases of mammalian fertilization. Several observations suggest that the plasminogen activator/plasmin system might also play a role in mammalian fertilization. Movement characteristics of bovine sperm incubated with different concentrations of plasmin were investigated using a computer-assisted automated semen analysis system. Sperm were incubated up to 4h in a modified Tyrode's medium (control) and 0.1, 1, 10 and 100 mU/ml of plasmin. The percentage motile sperm was significantly higher at 0 h for sperm incubated in 1, 10, and 100 mU of plasmin. Relative to sperm incubated in control medium, lateral head displacement (ALH), curvilinear velocity, beat cross frequency, path velocity and straight line velocity (VSL) of sperm treated with 100 mU of plasmin for 0 h were increased. After 2h of incubation, sperm treated with 100 mU of plasmin showed an increase in ALH, but a decrease in VSL, straightness and linearity. The effect of plasmin on most motility parameters appears to be direct since all these parameters were affected at 0 h of incubation. Our results support the notion of hyperactivation of bovine spermatozoa following incubation with different concentrations of plasmin. The present work provides additional information to further characterize motility movement of bovine sperm associated with final preparation for fertilization.

Animals↗

Medullary and mesencephalic pathways and connections of lateral line neurons of the spiny dogfish Squalus acanthias.

The neuronal connections of the electrosensory dorsal and the mechanosensory medial octavolateralis nuclei of the spiny dogfish Squalus acanthias were studied by horseradish peroxidase, autoradiographic and axonal degeneration methods. Efferents from each nucleus, in addition to extensive commissural components, give rise to ipsilateral and contralateral lemnisci that ascend to midbrain levels and terminate among the cells of the lateral mesencephalic nucleus (LMN). Within LMN, electrosensory and mechanosensory neurons distribute dorsolateral and ventromedial in position, respectively. Ascending fibers of both modalities also terminate within the central zone of the optic tectum. The LMN of spiny dogfish sharks that possess a primitive pattern of midbrain organization is homologous to parts of the lateral mesencephalic nuclear complex of batoids that possess a more derived pattern of midbrain organization. Other fiber connections of the dorsal and medial octavolateralis nuclei appear to differ from each other, indicating that electrosensory and mechanosensory lateral line information is carried over separate pathways at least to midbrain levels of the brain stem. For example, nucleus B, a feedback center, occupies a position in the descending lateral line pathways of sharks and skates similar to nucleus praeeminentialis of many electrosensory teleosts. The dorsal octavolateralis nucleus of sharks and skates receives afferents from nucleus B but there is no evidence that nucleus B directly feeds back to the medial octavolateralis nucleus of the spiny dogfish. Moreover, unlike the dorsal nucleus, the medial nucleus of Squalus is reciprocally linked with the octaval system.

Animals↗

Induction by transforming growth factor-beta1 of epithelial to mesenchymal transition is a rare event in vitro.

INTRODUCTION: Transforming growth factor (TGF)-beta1 is proposed to inhibit the growth of epithelial cells in early tumorigenesis, and to promote tumor cell motility and invasion in the later stages of carcinogenesis through the induction of an epithelial to mesenchymal transition (EMT). EMT is a multistep process that is characterized by changes in cell morphology and dissociation of cell-cell contacts. Although there is growing interest in TGF-beta1-mediated EMT, the phenotype is limited to only a few murine cell lines and mouse models. METHODS: To identify alternative cell systems in which to study TGF-beta1-induced EMT, 18 human and mouse established cell lines and cultures of two human primary epithelial cell types were screened for TGF-beta1-induced EMT by analysis of cell morphology, and localization of zonula occludens-1, E-cadherin, and F-actin. Sensitivity to TGF-beta1 was also determined by [3H]thymidine incorporation, flow cytometry, phosphorylation of Smad2, and total levels of Smad2 and Smad3 in these cell lines and in six additional cancer cell lines. RESULTS: TGF-beta1 inhibited the growth of most nontransformed cells screened, but many of the cancer cell lines were insensitive to the growth inhibitory effects of TGF-beta1. In contrast, TGF-beta1 induced Smad2 phosphorylation in the majority of cell lines, including cell lines resistant to TGF-beta1-mediated cell cycle arrest. Of the cell lines screened only two underwent TGF-beta1-induced EMT. CONCLUSION: The results presented herein show that, although many cancer cell lines have lost sensitivity to the growth inhibitory effect of TGF-beta1, most show evidence of TGF-beta1 signal transduction, but only a few cell lines undergo TGF-beta1-mediated EMT.

Actins↗

A case of Chlamydia trachomatis infection in a renal allograft patient.

We describe a renal allograft patient with a Chlamydia trachomatis infection. A 43 year-old man was diagnosed with end-stage renal disease in 1985 which necessitated the transplantation of a cadaver kidney in 1986. The kidney was rejected two years later. A second transplantation was performed in 1991. At the beginning of 1998 symptoms and signs of chronic renal failure and dysuria set in. Routine microbiological studies were negative. Cell culture on McCoy cell line was positive for an active infection with C. trachomatis--initially 3+, then 2+, 1+ and negative following treatment. The patient was positive on the AMPLICOR CT/NG test (Roche Diagnostic Systems, Branchburg, USA) twice with OD values OVER--above 2 at 450 nm wavelength measured on an ELISA reader. The patient received treatment with azithromycin and doxycycline for 10 days following which the serum creatinine levels fell and the creatinine clearance values improved. Dynamic microbiological follow-up showed disappearance of C. trachomatis as evidenced by the negative PCR test. We conclude that the deterioration of renal function in our patient is complex but the infection with C. trachomatis is part of the complex of the underlying chronic renal failure and immunosuppressive treatment.

Adult↗

Primary culture of rabbit gallbladder epithelial cells in collagen gel matrix.

Primary culture of gallbladder epithelial cells obtained from normal rabbits was attempted in collagen gel matrix for up to 6 weeks. Fluid medium containing 0.02% ethylenediaminetetraacetic acid and 0.25% trypsin was poured into the gallbladder lumen. The pellets obtained by centrifugation of recovered fluid contained many isolated epithelial cells and a few small cell clumps. These pellets were dispersed and embedded inside collagen gel matrix and cultured in William's medium E supplemented with fetal calf serum and epidermal growth factor. The three-dimensional outgrowth from individual cells and small cell clumps consisted predominantly of spherical cystic masses 2-4 days later. These cysts contained mucin and were covered by a single layer of cuboidal or low columnar epithelial cells. Electron microscopy revealed the epithelial arrangement of cells lining the cyst walls, and these cells were similar to gallbladder epithelial cells in vivo. These epithelial cells showed active mucin secretion into the cystic cavities. Cytokeratin was diffusely present in the cytoplasm. This isolation and culture system provides a reproducible and consistent method for sustained growth of normal gallbladder epithelial cells from normal tissue in primary culture and seems valuable for investigating pathologic conditions of the gallbladder.

Animals↗

Displaced intra-articular fractures of the tarsal navicular.

Between 1980 and 1987, twenty-one patients who had a displaced fracture of the body of the tarsal navicular were treated with open reduction and internal fixation. A classification system was devised on the basis of the direction of the fracture line, the pattern of disruption of the surrounding joints, and the direction of displacement of the foot. In a Type-1 injury, the fracture line is in the coronal plane and there is no angulation of the fore part of the foot. In a Type-2 fracture, the primary fracture line is dorsal-lateral to plantar-medial, and the major fragment and the fore part of the foot are displaced medially. In a Type-3 injury, there is a comminuted fracture in the sagittal plane of the body of the tarsal navicular, and the fore part of the foot is laterally displaced. Satisfactory reduction, which was defined as restoration of more than 60 per cent of the joint surface in the anteroposterior and lateral planes, was achieved in all Type-1 injuries, 67 per cent of the Type-2 fractures, and 50 per cent of the Type-3 fractures. Radiographic evidence of healing was seen at an average of 8.5 weeks after injury. At an average follow-up of forty-four months (range, twelve to 106 months), a good result was noted in fourteen patients (67 per cent); a fair result, in four (19 per cent); and a poor result, in three (14 per cent). Both the type of fracture and the accuracy of the operative reduction directly correlated with the final clinical outcome.

Adolescent↗