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Background: Traditional Le Fort III osteotomies have been described by several authors; however, few have reported the distances advanced and stability over time. Methods: The authors assessed their last 30 Le Fort III osteotomies with respect to the immediate incisor advancement achieved at surgery and long-term advancement as measured at the A-point from preoperative and postoperative cephalometric tracings. The authors then compared their results with those in the literature for Le Fort III distraction techniques. Comparisons were made with respect to distraction distance maintained, the need for bone grafting, airway results, morbidity, and cost. Results: The mean incisor advancement at the time of surgery as recorded in 14 patients was 21.6 mm (range, 12 to 28 mm). The long-term cephalometric A-point measurements in 14 patients demonstrated a mean of 14.14 mm (range, 8 to 25 mm). Conclusion: The authors conclude that, at the present time, no significant improvement in the results using Le Fort III distraction osteogenesis when compared with traditional methods has been shown. more...

The flavoenzyme uridine 5'-diphosphate (UDP)-galactopyranose mutase (UGM) plays a key role in the cell wall biosynthesis of many pathogens, including Mycobacterium tuberculosis. Using a synthetic fluorescent ligand, we screened 16 000 compounds in a fluorescence polarization assay. Effective inhibitors of UGM were identified. more...

WM Kuzon, JR Marcus, LD Kerluke, JH Phillips. African spitting cobra (Naja nigricollis) bite of the hand. Can J Plast Surg 1994;2(2):90-92. Fifty thousand snakebites occur annually in North America. of these, about 8000 result in envenomation by poisonous species. In North America, 98% of poisonous snakebites are caused by pit vipers (Crotilidae). This report describes a Naja nigricollis (family Elapidae, the African spitting cobra) bite of the hand that occurred in Ontario. This species is common in West Africa and is popular with North American collectors. Its venom is quite different from the venoms of pit vipers and results in significant tissue necrosis. The management of a bite by N nigricollis requires aggressive medical and surgical treatment. more...

The authors report on their experience with a particular hydroxyapatite cement in the pediatric population and review cases that elucidate potential limitations of its use in this population. In all patients, the implant was used for recontouring and augmenting the cranial vault. Seven of 15 patients had a direct communication between sinus mucosa and the implant at the time of surgery. Three of the seven patients developed late postoperative inflammatory reactions of the surgical site with delamination of the implant. Each patient required an aggressive irrigation and debridement with removal of the delaminated hydroxyapatite. Pathologic findings showed evidence of a foreign body inflammatory reaction in the tissue, and mixed bacterial flora were identified in all specimens. No late problems with the cement were seen in patients without a communication to the sinuses. Our findings suggest that the use of BoneSource, an essentially nonviable, nonvascularized implant, in areas exposed to bacterial contamination is contraindicated in the pediatric population. BoneSource and other similar hydroxyapatite biomaterials do have a role as implants in the craniofacial skeleton. The indications and contraindications of these substances will need to be further defined for wide acceptance to occur. more...

[reaction: see text]. We report the synthesis of cyclic sulfates by halocyclization. The resulting cyclic sulfate products can be opened selectively with sodium azide to transform them into highly functionalized compounds that contain azide, alcohol, and halide groups. more...

The rate of, and possible risk factors for, postoperative craniofacial infection is unclear. To investigate this problem, we reviewed 349 cases of craniofacial skeletal procedures performed from 1996 to 1999 at our institution. Infection rate was determined and correlated with the use of implants, operative site, and cause of deformity. The inclusion criteria consisted of all procedures requiring autologous or prosthetic implantation in craniofacial skeletal sites, as well as all procedures involving bone or cartilage resection, osteotomies, debridement, reduction and/or fixation. Procedures that did not involve bone or cartilage surgery were excluded. The criteria for diagnosis of infection included clinical confirmation and one or more of 1) intravenous or oral antibiotic treatment outside of the prophylactic surgical regimen; 2) surgical intervention for drainage, irrigation, and or debridement; and 3) microbiological confirmation. Among the 280 surgical cases that fit the inclusion criteria and had complete records, there were 23 cases of postoperative infection (8.2%). The most common site for postoperative infection was the mandible (infection rate = 16.7%). Multiple logistic regression analysis revealed gunshot wound to be the most significant predictor of postoperative infection. Additionally, porous polyethylene implantation through a transoral route was correlated with a significant risk of postoperative infection. more...

To tabulate and assess quantitative differences between anthropometric and corresponding radiographic cephalometric measurements obtained from the same persons, 19 projective linear measurements were taken from the surface of the heads and faces of 41 patients with cleft lip, cleft palate, or both, all of whom were white North Americans aged 14 to 29 years. They underwent radiographic examination shortly afterward, and corresponding cephalometric measurements were obtained. Differences between the methods were assessed by the numeric differences between the mean values of concurrent measurements. Statistical difference was assessed by paired t test, Pearson product-moment correlations, and intraclass index for degree of agreement between findings. By numeric difference, 6 of 19 anthropometric measurements were similar to (within 2% of) those taken from radiographs. Paired t tests disclosed significant differences between 16 of 19 measurements. Half of the six surface measurements similar to their skeletal counterparts showed no statistical difference; the other half showed only moderately significant differences. Differences between the 13 "dissimilar" measurement pairs (differences > 2%) were highly significant. Good correlations were found in five of the six similar measurements, which may have an important prognostic value in understanding changes in the craniofacial measurements of the face. Knowledge of the correlations between all major measurements of the head and face on the surface and skeleton is essential for anticipating changes in the morphologic characteristics of the growing face. more...

Screw failure during insertion is not an uncommon problem, especially with the micro and mini fixation systems. In this study, the holding power of 1-, 1.5-, and 2-mm screws was tested at various simulated bone thicknesses of 1, 2, 3, 4, and 5 mm with an increasing pilot hole size. This was done to ascertain the effects of pilot hole size on screw failure and any subsequent tradeoff with respect to decrease in holding power. For the 1-mm screws, there was no statistically significant decrease in holding power of the screws with increasing pilot hole size that ranged from 70 to 85 percent of the external diameter of the screw. For the 1.5-mm screw, a critical pilot hole size was found to be 1.24 mm (82 percent of the screw's external diameter), with no statistically significant decrease in holding power in the 1-, 2-, and 3-mm thickness blocks. For the 2-mm screws, the critical pilot hole size was found to be 1.65 mm (83 percent of the screw's external diameter). A statistically significant decrease in holding power was observed after this drill hole size in all thicknesses. Commercially available systems use drill bits that represent approximately 70 to 75 percent of the external diameter of the screw. Our results show that the pilot hole size for the 1-, 1.5- and 2-mm screws can be increased to 80 to 85 percent of the screw's external diameter without losing significant holding power.(ABSTRACT TRUNCATED AT 250 WORDS) more...

This case report documents echocardiographically a thromboembolus actively traversing a patent foramen ovale in a 72-year-old man with a dilated cardiomyopathy and systemic lupus erythematosis complicated by chronic low-grade disseminated intravascular coagulation and multiple lower extremity deep venous thromboses. With intravenous heparin therapy, there was apparent resolution of this thromboembolus without clinical evidence of systemic embolization. more...

The potential use of distraction osteogenesis in mandibular reconstruction has been limited by its questionable efficacy in previously radiated bone. We studied five mongrel dogs that had a hemimandible rendered edentulous and underwent a full course of external beam radiation therapy (50 Gy/20 fractions). Six months after completion of radiotherapy, a 2-cm critical-size segmental mandibular defect was created and stabilized with a stainless steel plate. A proximal mandibular transport segment was then formed and an external lengthening apparatus (Orthofix) applied. By means of bifocal distraction osteogenesis, the defects were filled with new bone in a period of 30 days in four of five dogs. Histologic analysis and fluorochrome microscopy confirmed the formation of new cortical bone. Our results suggest that distraction osteogenesis is successful in previously radiated bone and that it may be a simple method of mandibular reconstruction following ablative head and neck surgery. more...

In chromaffin granule ghosts, the Na+/Ca2+ exchanger in the granule membrane can provide a high affinity (Km 1-3 microM) and high capacity (Vmax 50-100 nmol mg min-2) mechanism for Ca2+ accumulation. The activity of the Na+/H+ antiporter can be used to couple Ca2+ uptake via Na+/Ca2+ exchange to ATP-dependent proton translocation via the granule membrane H(+)-ATPase. Therefore, Ca2+ uptake can be indirectly linked to the proton pump. However, under conditions designed to mimic the environment of a granule in the cytosol of a chromaffin cell, measured rates of Ca2+ uptake are low, a free Ca2+ concentration of about 5 microM in the ghost matrix being attained. Under such circumstances, the granules seem unlikely to play a major role in calcium homeostasis in the intact cell. more...

Tetanus toxin (about 1 nM) inhibits 70% of the nicotine-evoked release of catecholamines from intact adrenal medullary chromaffin cells after 20 h of incubation and 30% of the K+-evoked release. Inhibition of Ca2+-evoked release from detergent-permeabilized cells requires higher concentrations of toxin (about 1 μM) toxin, but is maximal after 12 min. Preincubation of the intact cells with ganglioside GT1 in the absence of toxin also inhibits evoked secretion. 125I-labelled toxin bound specifically to these cells; the binding capacity was greater at pH 6 (about 1 pmol toxin/mg cell protein) than at pH 7.4 (about 0.25 pmol). In both cases there were at least two binding components: one of high affinity (Kd about 1 nM) accounting for about 20% of total binding and one of lower affinity (Kd 10–20 nM). Preincubation of the cells with ganglioside increased the binding capacity, but did not affect the Kd of the lower affinity component. Similar observations could be made when binding was measured immunocytochemically. Extraction of gangliosides from chromaffin cells and overlay experiments with radiolabelled toxin showed that, as well as GM3, the major ganglioside component of chromaffin cell membranes, a ganglioside having the chromatographic mobility of GTI was a major ligand for toxin. more...

The adverse effects of increased tension across a healing wound are well known. However, the effect of closing a wound in layers in order to decrease tension on the epidermis has been a source of controversy. It is hypothesized that deep tissue support decreases skin tension upon wound closure. In order to clarify this issue, a two-part study was designed to address the immediate effects of deep tissue support in vitro using fresh-frozen cadavers and in vivo on patients undergoing scheduled surgery. Closing skin tension was measured at standard reference points in coronal brow lift and rhytidectomy procedures performed with and without galeal closure and superficial musculoaponeurotic system (SMAS) procedures, respectively. Deep tissue support was found to significantly (p less than 0.05) decrease skin tension at the time of skin closure at standard reference points in coronal brow lift and rhytidectomy procedures performed on fresh-frozen cadavers. Similar significant (p less than 0.05) decreases in closing skin tension also were found in vivo in patients undergoing similar surgical procedures. Stress relaxation was not found to play a significant role in contributing to this immediate decrease in closing skin tension. It would appear, therefore, that deep tissue support, in the form of galeal closure and an SMAS procedure in coronal brow lift and rhytidectomy procedures, respectively, provides increased viscoelastic support, producing immediate significant decreases in closing skin tension in these procedures. The beneficial effects on wound healing, scar formation, tension-related trophic skin changes, and possible improved long-term results are discussed. more...

The use of craniofacial surgical techniques, extended open reduction, rigid fixation with plates and screws, and the replacement of severely damaged or missing bone with immediate bone grafting in the treatment of complex facial fractures has been applied to the management of severe gunshot wounds of the face. Early definitive bone and soft-tissue reconstruction has been performed in 37 patients. One-hundred and seventy-seven primary bone grafts were utilized in 33 patients for orbital, nasal, zygomatic, and maxillary reconstruction. Twenty-six patients required mandibular repair with compression or reconstruction plates. Soft-tissue reconstruction was provided by a combination of flaps. Four patients had extensive soft-tissue loss replaced by free vascularized omental flaps. The omentum provided circumferential coverage of the mandibular reconstruction and reconstruction of the floor of the mouth and was then tunneled in a circle through both cheeks into the middle and upper face. The omentum reconstructed deficits in the hard palate and upper buccal sulcus and was then wrapped around all zygomatic, orbital, and midfacial bone grafts and used to fill in dead space in the maxillary, ethmoid, and frontal sinuses. The omentum is not used to provide contour and bulk, but to cover bone grafts and plates and fill in dead space. Carefully shaped bone grafts provide the correct craniofacial scaffold. Early restoration of a midfacial bony scaffold and the prevention of soft-tissue contraction facilitate secondary reconstruction. Four late total nasal reconstructions with tissue-expanded forehead skin wrapped around bone grafts were performed. more...

Collapse of the zygomatic arch following trauma results in inadequate anteroposterior projection of the zygomatic body and an increase in facial width. Accurate assessment of the position of the zygomatic arch in relation to the cranial base posteriorly and the midface anteriorly is the key to the acute repair of complex midfacial fractures and the secondary reconstruction of posttraumatic deformities of the orbitozygomaticomaxillary complex. Loss of projection of the zygomatic arch may occur with injuries confined to the orbitozygomaticomaxillary region or in association with complex midfacial fractures. A safe anatomic approach to the zygomatic arch allows exact anatomic restoration of the zygomatic arch using miniplates and screws and results in the reconstruction of an outer facial frame with a correct anteroposterior projection and facial width. The zygomatic arch injury is diagnosed using axial CT scanning. Three-hundred and seventeen arches have been exposed through a coronal incision following acute trauma and 47 arches have been exposed in patients requiring late correction of a posttraumatic orbitozygomaticomaxillary deformity. Permanent palsy to the frontal branch of the facial nerve has occurred in one patient following the exact definition of the anatomy of this region. more...

This paper investigates the relationship between bone resorption, the process of bone revascularization, and graft fixation. Vital staining techniques and microangiography were used to study the extent of graft revascularization of fixed and nonfixed endochondral (rib) and membranous (skull) onlay bone grafts in 20 adult sheep mandibles bilaterally. This assessment was carried out at 2 and 20 weeks postoperatively. Sequential fluorochrome staining was performed to examine the pattern of new bone deposition. Fixation was achieved using the lagscrew technique. At 2 weeks, membranous bone demonstrated a greater area of graft revascularization if fixed than if the graft was not fixed. The opposite result was seen for endochondral grafts, where nonfixed grafts showed a greater area of revascularization than fixed grafts. At 20 weeks, all bone that was present was fully vascularized. The inconsistencies in the results on the relationship between fixation and revascularization for membranous and endochondral grafts in the early stages of healing (2 weeks) suggest that although revascularization is a necessary precondition for bone resorption and deposition, biomechanical and structural factors may be a more satisfactory explanation for the differences observed in the maintenance of bony volume. more...

The pronounced variability of the cranial base angle and the degree of maxillary hypoplasia in Crouzon patients is well established in the literature. However, the correlation between these two variables has not been studied previously in Crouzon patients who have not undergone surgery. We studied the nasion-sella-basion and sella-nasion-subspinale (SNA) angles in 16 patients with Crouzon's syndrome, but who had not undergone surgery, and found that such a correlation does not exist. Patients with basilar kyphosis and lordosis manifested variable degrees of maxillary hypoplasia. Furthermore, normal skull base angle in Crouzon patients was not associated with normal SNA angle. more...

Thirty-five AIDS patients (mean CD4 count 44 x 10(6)/L) with chronic cryptosporidiosis were treated with letrazuril at an initial oral daily dose of 50 mg in an open-label Phase I prospective trial. Treatment was continued for > or = 10 days and for as long as there was a response. The majority of subjects (91%), had previously failed paromomycin treatment. At baseline, 74% of patients had moderate (five to nine bowel movements per day) to severe (> 10 bowel movements per day) diarrhea. Twenty-three subjects (66%) had a clinical response within a mean of 1.7 weeks of treatment initiation. Twenty-two patients had a partial response (> 50% reduction in bowel movements per day for > or = 1 week), one patient had a complete response (two or fewer bowel movements per day). Of the responders, 15 (65%) had a clinical relapse with worsening diarrhea at an average of 1.2 months following initiation of letrazuril. The other eight (35%) had had symptom control for an average of 2.9 months from initiation of letrazuril to the latest follow-up. Microbiologic eradication was demonstrated in 10 (40%) of 25 patients with follow-up stool examinations. Seven patients (20%) experienced a rash, all within 1 week of starting the drug, and resolved in all patients when the drug was discontinued. In conclusion, severely immunocompromised AIDS patients with refractory cryptosporidiosis may show a modest, short-lived response to letrazuril. Microbiologic response is variable and relapse high. Rash is a major limiting side effect of the drug. more...

Chromaffin granules, the secretory vesicles of the adrenal medulla, have a Na+/H+ exchange activity in their membranes which brings their proton gradient into equilibrium with a Na+ gradient. This explains why Na+ is mildly inhibitory to amine transport (which is driven by the H+ gradient) The activity can be demonstrated by using accumulation of 22Na+ in response to a pH gradient that is either imposed by diluting membrane ‘ghosts’ into alkaline media, or generated by ATP hydrolysis. It can also be monitored indirectly by fluorescence measurements in which the pH inside ‘ghost’ is monitored by quenching of a fluorescent weak base. This method has been used to monitor Na+ entry into acid-loaded Șghosts’ of H+ entry into methylamine accumulation. The exchanger appears to be reversible and non-electrogenic, with a stoichiometry of 1:1. Using an indirect assay we measured an apparent Km for Na+ of 4.7 mM, and a Ki for amiloride, a competitive inhibitor, of 0.26 mM. Direct assays using 22Na+ suggested a higher Km. Ethylisopropylamiloride was not inhibitory. more...

In August 1983, a study on parasites, diseases, and health status was conducted on sympatric populations of fallow deer (Dama dama) and white-tailed deer (Odocoileus virginianus) from Land Between The Lakes, Lyon and Trigg counties, Kentucky. Five adult deer of each species were studied. White-tailed deer had antibodies to epizootic hemorrhagic disease (EHD) virus and Leptospira interogans serovariety icterohemorrhagiae, and fallow deer had antibodies to bluetongue and EHD viruses. Serologic tests for bovine virus diarrhea virus, infectious bovine rhinotracheitis virus, parainfluenza3 virus, and Brucella spp. were negative. One white-tailed deer had an infectious cutaneous fibroma, and one fallow deer had pulmonary mucormycosis. White-tailed deer harbored 16 species of parasites, all of which are considered typical of the parasite fauna of this host in the southeastern United States. Fallow deer harbored nine species of parasites, including eight species known to occur in white-tailed deer on the area and one species (Spiculopteragia assymmetrica) that is not. All fallow deer had inflammatory lesions in the spinal cord and/or brain that were attributed to prior infection with meningeal worm (Parelaphostrongylus tenuis), indicating that P. tenuis infections are not always fatal for this species. The apparent high rate of exposure of Land Between The Lakes fallow deer to P. tenuis without a resultant high rate of clinical cerebrospinal parelaphostrongylosis is hypothesized to be due to a low prevalence and intensity of P. tenuis, partial innate resistance of fallow deer, and acquired immunity. more...

During a 4-year period, 33 patients with angiographic coronary artery spasm in the absence of significant fixed occlusive disease were reviewed. Sixteen patients had typical variant angina and 17 had catheter-induced spasm. All patients had one or more episodes of rest angina. Left ventriculography demonstrated mitral valve prolapse in 14 patients (42%) and end-systolic cavity obliteration in six (18%). Spasm was demonstrated to occur in the right coronary artery in 26 patients and in the left coronary artery in seven. Two patients had multivessel spasm. Comparing patients with variant angina and catheter-induced spasm demonstrated no significant difference in clinical, ECG, or angiographic parameters. Two patients with catheter-induced spasm had healed myocardial infarctions and both developed spontaneous non catheter-induced spasm in the infarct vessel. The majority of patients responded to long-acting nitrate therapy, though those with catheter-induced spasm tended to have more recurrent chest pain. Six patients were placed on calcium antagonist drugs with marked symptomatic improvement in five. This study suggests that patients with catheter-induced spasm are similar to those with variant angina and its angiographic documentation may be a marker for the identification of patients with vasospastic angina. more...

Municipal sewage sludges were characterized for a group of phenols classified as priority pollutants. The development of analytical methodology, including unique problems encountered when sampling, handling and analyzing phenolic compounds, are discussed. Percent recovery data for several sample types, as well as quality control procedures, are included. Samples were extracted via a liquid/liquid extraction centrifugation technique with dichloromethane. Cleanup was achieved by acid/base partitioning and automated gel permeation chromatography. Reverse phase high pressure liquid chromatography was used for separation of compounds employing an electrochemical detection system for quantitation. Sensitivities in the low picogram range were achieved for phenolic species in biosludge extract. more...

The neurosurgeon and plastic surgeon are increasingly called upon to manage the care of patients with combined injuries of the cranium and face. The authors briefly review the pathogenesis and classification of craniofacial fractures and outline historical approaches to them. Current principles of management are then discussed. Experience with 167 patients is presented with emphasis on surgical technique, the sequence of repair and early primary reconstruction. The controversial issue of fontal sinus fracture repair is addressed. The authors favour preservation of the frontal sinus cavity, where possible, and do not obliterate the nasofrontal duct. With injuries to the floor of the sinus, the base of the sinus and frontonasal duct are sealed with bone graft and a vascularised soft tissue flap and the sinus is cranialised. Immediate bone grafts, using split skull or rib, are used to reconstruct areas of bony destruction or loss. Ninety-eight patients required 402 grafts. Immediate bone grafting resulted in few complications and low incidence of secondary deformities needing correction. more...

We have measured the contents of Na+ and K+ in isolated chromaffin granules. Total contents varied between 227 and 283 nmol/mg of protein, equivalent to matrix concentrations of 53-66 mM. The value found depended on the isolation buffer used, and the ratio of the two ions reflected the composition of the buffer. We then measured the free concentration of each of these ions, and of Ca2+, in the matrix, by using a null-point method with acridine-fluorescence quenching. This monitored H+ fluxes induced by an ionophore in the presence of known concentrations of the ion in the supporting medium. In contrast with organic constituents of the matrix, which have low activity coefficients, Na+ and K+ were found to have activity coefficients around 0.8 Ca2+, however, was strongly bound: its free concentration was only 0.03% of the total. more...

Isolated chromaffin granules aggregate reversibly in the presence of Ca 2+ and Mg 2+ . The adhering membranes maximise their areas of contact, leading to distortions of the granules and, in many cases, to membrane rupture. The adhesion is accompanied by changes in the structure of the core: it is seen to withdraw from regions of the membrane that are involved in adhesion to other granules, although it remains in contact with the membrane at other places. At the same time the osmotic pressure within the granules increases and their soluble components are released to the medium. These processes can occur at 0 °C, and at low pH, as well as at room temperature and pH 7. Similar reorganisation of membranes and cores may occur during the process of Ca 2+ -dependent exocytosis in secretion. more...

Changing market and economic conditions, inflation, and Government controls are commonplace problems facing every business, and most managers, including retail management. But, amid all the panaceas proposed, the exhortations and guidelines of Government and the solutions developed by managers, many retailers are still left with an uncomfortable feeling that the current situation may be bigger than their capacity to handle it, and that past experience offers little guide to the appropriate actions to be taken in the future. There is a growing feeling that retail management at this time is facing a significant change of form, if not a change of life itself. This article attempts to present an overview of the current situation facing the retailing industry and to identify for retail management the critical forces affecting their businesses and the major areas of impact. This will help to indicate the appropriate areas for priority management attention at this time, and possible actions that should be taken if future profitability and growth is to be safeguarded, and the process of change is to be successfully managed. more...