Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “laterality defects”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 757 records · Page 42Linked to original sources
PubMed1990

Ocular findings in Treacher Collins syndrome.

We examined 14 patients from nine families referred with the diagnosis of Treacher Collins syndrome. We noted seven significant ocular findings including the following: a subnormal horizontal palpebral fissure length and inferomedial displacement of the lateral canthus in primary gaze; further medial displacement (4.0 mm or more) of the lateral canthus with resultant shortening of the horizontal fissure length on forced eyelid closure (fissure narrowing sign); partial-thickness eyelid colobomata localized to the nasal one half to two thirds of the lower eyelids; bilateral absence of the inferior lacrimal puncta; bilateral blepharoptosis; inferior displacement of the palpebral fissures; and regular astigmatism without any consistent orientation of the axis of astigmatism relative to the lower eyelid defects, blepharoptosis, or lateral canthus. The fissure narrowing sign correlates with known anatomic deficiencies in the Treacher Collins syndrome and may prove valuable in confirming the diagnosis in patients who lack certain typical features.

Adolescent↗
PubMed1996

[The repair of heel defect].

A total of 12 lateral leg complex flaps with gastrocnemius muscle, lateral cutaneous nerve of calf, cortex of fibula have been applied successfully to repair the heel defects. The walking and weight carrying function of feet were recovered. The author think that repair of heel defect might base on the anatomical, physiological function of heel to choose the appropriate complex flap.

Adolescent↗
PubMed2000

Bone healing around implants placed in a jaw defect augmented with Bio-Oss. An experimental study in dogs.

The present experiment was carried out to study some tissue reactions around implants that were placed in an edentulous ridge which had been augmented with deproteinized natural bovine cancellous bone mineral. In 4 male beagle dogs, the premolars in the right side of the mandible were extracted and a large buccal ridge defect was created by mechanical means. The bone plate at the lingual aspect of the defect was left intact. 5 months later, the distal 2/3 of the defect area was augmented with Bio-Oss (Geistlich Sons Ltd, Wolhusen, Switzerland) mixed with a fibrin sealer (Tisseel, Immuno AG, Vienna, Austria). After 3 months of healing, 3 fixtures (Astra Tech AB, Mölndal, Sweden; TiO-blast; 8x3.5 mm) were installed in the mandible; 2 were placed in the augmented portion and I was placed in the non-augmented portion of the defect. After a healing period of 3 months, abutment connection was performed and a plaque control period initiated. 4 months later, the dogs were sacrificed and each implant region was dissected. The tissue samples were dehydrated, embedded in plastic, sectioned in the bucco-lingual plane and examined in the light microscope. It was observed that osseointegration failed to occur to implant surfaces within an alveolar ridge portion previously augmented with Bio-Oss. In the augmented portion of the crest, the graft particles were separated from the host tissue as well as from the implant by a well-defined connective tissue capsule. Although the lingual aspect of all fixtures (test and control) was in contact with hard tissue at the time of installation, after 4 months of function, a deep vertical bone defect frequently had formed at the lingual surface of the implants. It was concluded that in this model (i) Bio-Oss failed to integrate with the host bone tissue and (ii) no osseo-integration occurred to the implants within the augmented portion of the crest.

Alveolar Ridge Augmentation↗
PubMedDate not supplied

Necessity for evaluation of anomalous pulmonary venous return before percutaneous closure of atrial septal defects--a case report.

About 10%-15% of patients with an atrial septal defect will have some form of anomalous pulmonary venous connection. With the advent of percutaneous closure of atrial septal defects, it is imperative that presence of partial anomalous pulmonary venous return be excluded to prevent unnecessary percutaneous closure in patients who would ultimately require a surgical approach. The authors herein report a 29-year-old man who underwent percutaneous closure of 2 atrial septal defects but was later found to have his left upper pulmonary vein draining into the innominate vein via a vertical vein. He subsequently underwent surgical repair of the anomalous pulmonary vein.

Adult↗
PubMed1999

A multidisciplinary approach to the healing of cranial and residual maxillary cleft defects by means of allogenous demineralized osseous implants and polylactic acid casts in dogs.

OBJECTIVE: The aim of this study was to evaluate the healing of artificially induced bony defects in dogs by means of demineralized allogenous bone powder (DBP) implants covered with polyhydroxy lactic acid (PLA) casts compared with DBP implants without the casts. DESIGN: Prospective animal study. SETTING: Research university. SAMPLE: Following a pilot study in which two dogs were used, four mongrel dogs between the ages of 18 and 24 months and weighing approximately 20 kg were used as subjects. INTERVENTIONS: Each experimental animal had bilateral maxillary alveolar clefts created. In a later procedure, each defect was repaired with a DBP implant, half of which were covered with a PLA96 matrix. Each animal also had a circular defect created in each parietal bone that was immediately covered with DBP implants, half of which were similarly covered with a PLA96 disk. MAIN OUTCOME MEASURE: Repeated technetium-99m methylene-diphosphate (99mTC MDP) uptake measurements were performed to evaluate bone metabolism during the healing period, while at relevant intervals, radiographs were taken of the healing alveolar cleft defects to register bone repair. After 1 year, the animals were euthanized for macroscopic and histologic evaluation. RESULTS: Histologically, the grafts covered with PLA96 were at a more advanced stage of healing than those without, and the cranial defects similarly were more advanced in the healing process than the alveolar defects. Uptake of 99mTC MDP into the cranial implants was at its maximal level after 1 week and then gradually decreased until, after 7 weeks, it was not significantly different from zero. Cranial defects covered with a PLA95-enhanced implant showed a mean maximum count rate of 275, while the plain DBP side showed a mean maximal count rate of 150. Alveolar defects with the plain DBP implant showed a maximum count rate in the first week; those with the PLA95 enhanced implant showed maximum uptake during the second week. On both sides, there was a gradual decrease to the base value in the seventh week. The mean maximum count on the PLA96-enhanced side was 285, while on the plain DBP side, the corresponding value was 320. CONCLUSION: Although an advantage of the combination was established for parietal cranial defects, no advantage was seen for alveolar cleft defects in this experimental setup.

Alveoloplasty↗
PubMed2002

Evaluation of Bioglass/dextran composite as a bone graft substitute.

Allogenic and alloplastic bone graft substitutes serve either as bioinert or bioactive osteoconductors. Bioglass is a bioactive osteoconductor and also shows osteoproductive effects due to its high level of bioactivity. However, the material lacks some cohesiveness when used in augmenting certain bony surfaces, i.e. large or pleomorphic defects. The addition of medium molecular weight dextran modifies the particulate to a putty consistency and improves the handling characteristics. The objective of this study is to evaluate the influence of dextran upon the bioactive properties of Bioglass. Standardized bony defects in the lateral femoral condyles in adult New Zealand white rabbits were filled with one of five material groups: (1) autogenous bone; (2) Bioglass particulate; (3) Bioglass particulate mixed with dextran to a putty-like consistency; (4) a mixture of Bioglass and autogenous bone; (5) a mixture of Bioglass putty with autogenous bone. Postoperative healing was observed after periods of 2 days, 1, 2, 3, 6 and 12 weeks. Results showed no evidence of toxicity in the dextran-containing materials, and defects in all test groups showed 100% bony ingrowth within 6 weeks. The addition of medium molecular weight dextran did not appear to alter the bioactive properties of Bioglass and had no adverse influence upon the ingrowth of bone into the defect sites.

Animals↗
PubMed1998

[Impact of the correction of the attenuation in myocardial perfusion image with SPECT].

BACKGROUND: The aim of this study was to assess the effect of attenuation correction on gender differences in normals and to evaluate its effect on the size and severity of lateral wall perfusion defects in patients with circumflex artery disease. MATERIAL AND METHODS: Tomographic myocardial perfusion imaging with and without attenuation correction was performed on 32 patients with circumflex artery stenosis and compared with patients with less than 5% likelihood of coronary disease. Images were acquired with a triple headed scanner and reconstructed using an iterative algorithm and re-sliced in the short axis plane. Regional count densities were measured on selected short axis slices from the base to the apex in both patients and normals. RESULTS: All attenuation corrected images were found to be more uniform than the non attenuation corrected images on the patients with less than 5% likelihood of coronary artery disease. The coefficient of variation was 12.5% for non attenuation corrected images versus 9.9% for attenuation corrected images (p < 0.0001). When female and male segmental count distributions were compared, significant differences were found which were resolved after attenuation correction. In patients with circumflex artery stenosis, the anterolateral and lateral count densities were lower at all levels with attenuation corrected images with an increasing difference from base to apex. CONCLUSIONS: The use of attenuation correction results in a greater uniformity in normals and an improved estimation of extent and severity of perfusion defects in the territory of the circumflex artery.

Adult↗
PubMed2005

[Autologous rib graft for restoration of continuity defects of the mandible].

BACKGROUND: Reconstruction of mandibular defects following tumor resection in infants is a particular challenge. Although autologous rib grafts have no relevance nowadays for restoration of mandibular bone defects following ablative tumor surgery due to limited bone stock and the availability of other donor areas, they are a useful surgical alternative following tumor surgery in infants. PATIENTS AND METHOD: We here report on the 5- and 10-year follow-up of two children who were diagnosed with benign tumors of the mandible with osseous destruction at the age of 4 and 6 months, respectively. Histological diagnoses were melanotic neuroectodermal tumor and hemangioendothelioma of the mandible. Following continuity resection of the mandible lateral mandibular bone defects were restored using autologous rib grafts. Yearly clinical and radiological follow-up visits in both children were performed to assess growth of the facial skeleton as well as mandibular growth. RESULT: Cephalometric measurements on panorex films as well as 3D CT scans revealed slight vertical growth excess and transversal growth inhibition of the reconstructed mandible in comparison with the non-operated side. DISCUSSION: Although further growth of rib grafts is difficult to predict and occlusal disharmony may occur due to physiologic maxillary growth and growth of the unaffected mandible, we believe that autologous rib grafts can be ideally used for restoration of mandibular continuity defects in newborns. Clinical follow-up visits on a yearly basis and orthodontic controls are useful for early orthodontic treatment of growth deficits. Further corrective surgery with bone augmentation or osseous distraction is required following completion of growth of the facial skeleton.

Bone Transplantation↗
PubMed2005

Impaired concentration due to frontal lobe damage from two distinct lesion sites.

BACKGROUND: Investigations of cognitive deficits after frontal lobe damage have commonly relied on multidimensional tests and relatively coarse specification of lesion anatomy. Some form of impairment in attention is often asserted to cause the revealed deficits. OBJECTIVE: To describe a disorder of attention in patients with frontal damage using a theoretical model of the fundamental cognitive processes that underlie attention. METHODS: The ability to perform a task of concentrated responding was studied in 43 patients with well-defined chronic frontal lesions and 38 control subjects using a continuous reaction time (RT) test. Performance measures were mean RT, RT across blocks of the test, and errors. Lesion measures were coarse localization and a hot-spot analysis to detect finer grained lesion effects. RESULTS: Only patients with lesions in the right superomedial (SM) frontal regions had significantly prolonged RT consistently across the entire test. The critical lesion was in Brodmann's areas 24, 32, 9, and 46 days and in the adjacent corpus callosum. Patients with lesions in left lateral frontal (LL) regions made significantly more errors on the 20% of trials in the first block. The critical lesion was in areas 44, 45, and 47/12. CONCLUSION: Concentrating attention to respond is affected by lesions in two different frontal regions for reasons that reflect impairments in different cognitive processes. Right superomedial lesions cause an insufficient energizing of attention to respond. Left lateral lesions cause defective setting of specific stimulus-response contingencies. Constrained tests of attention can demonstrate impairments in specific cognitive operations following lesions to different regions of the frontal lobes.

Adult↗
PubMedDate not supplied

Axial pattern flap based on the genicular branch of the saphenous artery in the dog.

Axial pattern flaps based upon the genicular branch of the saphenous artery and medial saphenous vein were developed in eight dogs. On one hind limb of each dog, the experimental flap was raised and immediately transferred to a cutaneous defect created over the lateral aspect of the lower limb distal to the stifle. A control flap was elevated and transferred on the opposite hind limb with the genicular branches of the saphenous artery and vein ligated and divided at the base of the flap. Eighty-nine per cent of the length of the flap survived in those flaps in which the genicular vessels were left intact, whereas only 54% of the flap's length survived in the control flaps. Postoperatively, all dogs were bearing weight on the limbs normally. The genicular axial pattern flap may have special clinical application in cases of cutaneous defects involving the lateral aspect of the tibia.

Animals↗
PubMed1991

Phosphorus-31 two-dimensional solid-state exchange NMR. Application to model membrane and biological systems.

Two-dimensional solid-state 31P NMR has been used to investigate the orientational exchange of phospholipids in gel and liquid-crystalline aqueous multilamellar dispersions and oriented multibilayers, and in biological membranes. In liquid-crystalline L alpha multilamellar dispersions, orientational exchange originates from the lateral diffusion of phospholipid molecules over the curved surface of the liposomes and is manifest by an increase in off-diagonal intensity, which correlates the 90 and 0 degrees orientations of the membrane normal with respect to the magnetic field when the system is fully exchanged. Spectral simulations of the time evolution of exchange allowed determination of the correlation times tau d for lateral diffusion. For DMPC and DPPC at comparable reduced temperatures, tau d values of 44 and 8 ms were obtained, respectively. The nature and rate of exchange observed for POPE at 30 degrees C is similar to that of DMPC at the same temperature. The measured correlation times are consistent with diffusion rates obtained by FRAP for liposomes with radii in the 1 micron range. In the gel phase of DPPC (30 degrees C), little orientational exchange is observed at mixing times up to 200 ms, demonstrating that the lateral diffusion is very slow. The correlation time for orientational exchange obtained from spectral simulations was approximately 900 ms; thus, exchange in the gel state is at least two orders of magnitude slower than in the liquid-crystalline state. In the P beta (ripple) phase, at temperatures between 34 and 39 degrees C, significant exchange is observed for mixing times between 50 and 200 ms. Exchange is also observed in oriented samples of DPPC in the P beta phase for mixing times of 50 ms, but not for oriented liquid-crystalline samples for mixing times up to 100 ms. The exchange observed in the ripple phase could originate from rapid lateral diffusion of "fast" diffusing phospholipid within defect structures, and/or from "slow" lateral diffusion of ordered phospholipid over the ripples. 2D experiments were also performed on pig erythrocyte ghosts and on intact pig spinal cord. Significant orientational exchange was observed with the erythrocyte ghosts at a mixing time of 200 ms, but almost no exchange was observed with the spinal cord at the same mixing time. Spectral simulations suggest tau d values of approximately 400 ms and 1.3 s for the erythrocyte ghosts and spinal cord at 30 degrees C. The results demonstrate that exchange in the biological membranes is significantly slower than in the model membrane systems, which suggests that the cell surfaces are relatively "smooth," i.e., any local surface perturbations are either present in small number or have little effect on the mean orientation of the phospholipids with respect to the membrane normal.

1,2-Dipalmitoylphosphatidylcholine↗
PubMed2005

Intrapartum spontaneous uterine rupture following uncomplicated resectoscopic treatment of Asherman's syndrome.

Since Asherman first published his series of intrauterine synechiae in 1948, only a few physicians have described the obstetric complications of patients who conceived following surgical treatment of intrauterine synechiae. We present a woman with a history of resectoscopic resection of intrauterine adhesions with a term pregnancy and spontaneous uterine rupture that occurred during the intrapartum period. At emergent cesarean section, hemoperitoneum of approximately 1500 mL was noted and a 10-cm defect was present in the lateral uterine wall; the edges of the defect were bleeding actively. Because of the potential for a disastrous outcome in the rupture of the pregnant uterus, patients treated for Asherman's syndrome should be identified early and appropriate precautions should be taken in their obstetric management.

Adult↗
PubMedDate not supplied

Skin graft reconstruction of the composite resection defect.

BACKGROUND: Reconstruction of the composite resection defect should provide for adequate speech and swallowing functions. Poorly designed reconstructive efforts can result in significant oral dysfunction. The composite resection defect can be reconstructed by a variety of methods. The split-thickness skin-graft method provides excellent speech and swallowing functions with minimal morbidity. METHODS: Forty-three patients who underwent composite resections and were reconstructed by split-thickness skin graft (STSG) were analyzed. The patients' charts were reviewed for oncologic outcome, speech and swallowing functions, and length of hospital stay. RESULTS: Speech and swallowing functions were excellent. At last follow-up, more than 90% of the patients tolerated either a soft or regular diet. The length of hospital stay was only 13 and 18 days for patients who underwent marginal and lateral segmental mandibulectomy, respectively. There were few complications. Radiation therapy had no adverse effects on the grafts. CONCLUSION: The STSG method is our preferred method for reconstruction of marginal or lateral segmental mandibulectomy defects that do not require tissue bulk.

Aged↗
PubMed2006

Disruption of MEF2 activity in cardiomyoblasts inhibits cardiomyogenesis.

Myocyte enhancer factors (MEF2s) bind to muscle-specific promoters and activate transcription. Drosophila Mef2 is essential for Drosophila heart development, however, neither MEF2C nor MEF2B are essential for the early stages of murine cardiomyogenesis. Although Mef2c-null mice were defective in the later stages of heart morphogenesis, differentiation of cardiomyocytes still occurred. Since there are four isoforms of MEF2 factors (MEF2A, MEF2B, MEF2C and MEF2D), the ability of cells to differentiate may have been confounded by genetic redundancy. To eliminate this variable, the effect of a dominant-negative MEF2 mutant (MEF2C/EnR) during cardiomyogenesis was examined in transgenic mice and P19 cells. Targeting the expression of MEF2C/EnR to cardiomyoblasts using an Nkx2-5 enhancer in the P19 system resulted in the loss of both cardiomyocyte development and the expression of GATA4, BMP4, Nkx2-5 and MEF2C. In transiently transgenic mice, MEF2C/EnR expression resulted in embryos that lacked heart structures and exhibited defective differentiation. Our results show that MEF2C, or genes containing MEF2 DNA-binding sites, is required for the efficient differentiation of cardiomyoblasts into cardiomyocytes, suggesting conservation in the role of MEF2 from Drosophila to mammals.

Animals↗
PubMed1999

Different approaches for minimally invasive closure of atrial septal defects.

BACKGROUND: To improve the acceptance of cosmetic results after closure of atrial septal defects, anterior or lateral thoracotomies are preferred rather than median sternotomies. Along with the availability of minimally invasive techniques, a further reduction in incision length appeared feasible while preserving thoracic stability. METHODS: Various minimally invasive approaches differing in the type of incision and mode of cannulation have been applied under conditions of normothermic ventricular fibrillation. In technique 1 (n = 5), a right parasternal mini-incision was combined with a central aortic and bicaval cannulation. Technique 2 (n = 2) was composed of an anterior submammary mini-incision with femoral arterial and central bicaval cannulation. To optimize the surgical access, the transincisional cannulation of the superior vena cava was replaced by a percutaneous cervical cannulation (technique 3, n = 17). RESULTS: Effective atrial septal defect closure assessed by intraoperative echocardiography was achieved in all patients. Central neurologic complications were completely absent. Besides temporary atrial fibrillation in one case, no other cardiac complications occurred. There were no cases with complicated wound healing. CONCLUSIONS: Along with modified cannulation techniques and intraoperative echocardiography, minimally invasive techniques can be safely applied for atrial septal defect closure. Submammary incisions were highly accepted and allowed for adequate surgical exposure.

Adolescent↗
PubMed1993

Immune cell defects affect bone remodelling in osteopetrotic op/op mice.

The aim of the present work was to further characterize immunological defects in osteopetrosis. The op/op mutant mouse is of particular interest since a marrow cavity develops spontaneously in older animals. The interleukin production (IL-1, IL-2, IL-3, IL-4, IL-6), the presence of macrophage differentiation antigens and the evolution of the bone lesions were studied in osteopetrotic and normal mice. Low levels of IL-1, IL-3 and IL-4 were observed at the age of 6 weeks in the op/op mice. However, at 22 weeks of age, the level of IL-1 and IL-4 returned to normal value in these op/op mice whereas the level of IL-3 remained partially decreased at the same age. Furthermore, macrophage expression of MAC-2 antigen, reduced at 12 weeks of age was found to be normal 10 weeks later. These immunological defects and their recovery seems to be concomitant with the healing of the bone lesions.

Animals↗
PubMed1993

Reconstruction of skull defects in children and adolescents by the use of fixed cranial bone grafts: long-term results.

This article presents the long-term results of skull defect reconstruction in a series of 27 children studied between 1986 and 1990 (mean age, 8.4 yr; range, 1-17 yr). Causes of their defects were encephalocele (six patients), trauma (seven patients), tumor (eight patients), fibrous dysplasia (two patients), postsynostectomy defects (two patients), osteomyelitis (one patient), and Reye's syndrome with bone flap loss (one patient). All patients underwent clinical and computed tomographic scan documentation of their skull defects before and immediately after surgery and at least 1 year later. The average preoperative defect surface area measured 33 cm2 (range, 2.5-114 cm2). Skull defects were reconstructed in all patients with fixed autogenous cranial bone grafts. In the initial five patients, the grafts were fixed with interosseous wires, and in the remainder, they were fixed with a combination of miniplates and microplates and screws. Follow-up ranged from 12 to 66 months (mean, 31.4 mo). Complications were minimal, with no infection, plate or graft exposure, or intracranial injuries. In 24 of 27 patients, clinical examination and computed tomographic scans showed no evidence of skull defect or appreciable irregularity of donor or recipient sites. Two patients had documented small regions of graft resorption. One skull had palpable contour irregularities but without a bony defect. All patients have resumed routine activities and sports without special head protection. Repair of skull defects in children with fixed autogenous cranial grafts is a reliable method of reconstruction with minimal morbidity. Although we prefer miniplates and microplates and screws for fixation, the grafts fixed in place with interosseous wires did equally well.

Adolescent↗
PubMed2006

Vertical ridge augmentation by means of deproteinized bovine bone block and recombinant human platelet-derived growth factor-BB: a histologic study in a dog model.

The primary objective of this proof-of-principle study was to evaluate the outcome of vertical ridge augmentation in a standardized dog model by combining purified recombinant platelet-derived growth factor (rhPDGF-BB) and a block of deproteinized cancellous bovine bone. The secondary objective was to determine the value of a resorbable barrier membrane to improve the efficacy of the procedure. Six adult foxhounds were committed to bilateral surgical extraction of all four mandibular premolars. A vertical alveolar ridge defect was created at the time of the extractions. Three months later, the artificially created defects were grafted: Group A used a deproteinized bovine bone block in combination with a collagen barrier membrane, group B used a deproteinized bovine bone block infused with rhPDGF-BB only, and group C included a deproteinized bovine bone block infused with rhPDGF-BB, plus a collagen resorbable barrier membrane. After 4 months, the animals were sacrificed. Histologic examination of group B revealed a large amount of newly formed bone, and a large amount of bone-to-implant contact was visible in the areas of bone regeneration extending over the top of the implant cover screw. The results of this preclinical canine study provide proof-of-principle that rhPDGF-BB, used in combination with a deproteinized bovine block without placement of a barrier membrane, has the potential to regenerate significant amounts of new bone in severe mandibular ridge defects. In addition, the results seem to point to the importance of the periosteum as a source of osteoprogenitor cells in growth factor-mediated regenerative procedures.

Absorbable Implants↗