Controlled creation of a singular spinor vortex by circumventing the Dirac belt trick.

Persistent topological defects and textures are particularly dramatic consequences of superfluidity. Among the most fascinating examples are the singular vortices arising from the rotational symmetry group SO(3), with surprising topological properties illustrated by Dirac's famous belt trick. Despite considerable interest, controlled preparation and detailed study of vortex lines with complex internal structure in fully three-dimensional spinor systems remains an outstanding experimental challenge. Here, we propose and implement a reproducible and controllable method for creating and detecting a singular SO(3) line vortex from the decay of a non-singular spin texture in a ferromagnetic spin-1 Bose-Einstein condensate. Our experiment explicitly demonstrates the SO(3) character and the unique spinor properties of the defect. Although the vortex is singular, its core fills with atoms in the topologically distinct polar magnetic phase. The resulting stable, coherent topological interface has analogues in systems ranging from condensed matter to cosmology and string theory.

Predicting first-year relapses in children with nephrotic syndrome.

OBJECTIVE: More than half of the children diagnosed with nephrotic syndrome will have relapses. These can be infrequent relapses (IRs: <2 in 6 months or <3 in a year) or frequent relapses (FRs: >2 in 6 months or >3 in a year). Patients who relapse while on alternate day steroids or within 1 month of discontinuation of steroid therapy are considered steroid-dependent (SD; J Pediatr. 1982; 101:514-518). Patients with an IR course have a better long-term prognosis, and many of them have minimal-change disease without mesangial hypercellularity or sclerosis. The purpose of our study was to identify factors at initial presentation that could predict the relapse pattern in the first year after diagnosis, without taking into consideration the histopathology found on renal biopsy. DESIGN: We analyzed the medical records of children who were seen by us before March 1997 and followed for at least 1 year. Variables selected in the study were age, sex, race, presence or absence of hematuria, and days to remission (defined as protein-free) at the initial presentation, because they could relate to the pattern of relapses (ie, IR, FR, and SD). RESULTS: Of 70 patients, 14 were excluded because of insufficient data. There were 38 males (67.9%) and 18 females (32.1%), giving a male:female ratio of 1.8:1. Median age at presentation was 3.25 years (range: 1.5-13), and 76.9% were white, 8.9% black, 7.1% Hispanic, and 7.1% other. Of all the patients, 23 were IR (41.1%), 9 were FR (16.1%), and 24 were SD (42. 9%). Median days to remission were 10 (range: 2-60), on Prednisone 60 mg/M(2) daily. Hematuria was present initially in 26 patients (46. 4%), and absent in 30 (53.6%). Age, sex, race, and hematuria, as independent variables, were not predictors of relapses in the first year. However, using a stratified analysis based on the presence or absence of hematuria, we found that if the remission occurred within the first week of therapy, the patients without hematuria were more likely to be IR. The sensitivity and specificity of this finding were 67% and 89%, respectively, with a positive predictive value of 94%. CONCLUSION: We conclude that of all the presenting features, the rapidity of initial response to steroid therapy combined with the presence of hematuria, could predict future relapses and should be well documented.

Nephrotic syndrome associated with hypocomplementemia in a 4-year-old boy with hemophilia B.

PURPOSE: The case of a 4-year-old boy with hemophilia B with inhibitor who developed nephrotic syndrome is described. The possible association between factor IX therapy and nephrotic syndrome in patients with hemophilia B is discussed. PATIENT AND METHODS: A chart review of a 4-year-old boy with hemophilia B and an inhibitor who developed nephrotic syndrome with transient hypocomplementemia was performed. In addition, a literature search was undertaken to determine the prevalence of this association and possible etiologic factors. RESULTS: Although the nephrotic syndrome was resistant to steroid therapy and Bebulin (Osterreichisches Institut für Haemoderivate Ges.M.B.H., Subsidiary of Immuno AG, Vienna, Austria) infusions were continued, the edema resolved and proteinuria decreased. Seven month later, proteinuria, accompanied by transient hypocomplementemia, increased again. A rise in factor IX inhibitor level was observed. The patient received no immunosuppressive therapy, and exhibited a continuous decrease in urinary protein excretion over the following months. DISCUSSION: A discussion about possible differential diagnoses and a review of the literature are presented.

Cementifying fibroma: resection of recurrent mandibular lesion with microsurgical preservation of inferior alveolar nerve and immediate reconstruction.

Cementifying fibroma is a benign fibro-osseous lesion that may occur in either the mandible or the maxilla, with a predilection for the mandible. In the patient described, a recurrent mandibular cementifying fibroma was successfully resected, with microsurgical preservation of the inferior alveolar nerve and immediate reconstruction via an autogenous iliac bone graft.

Plasma Membrane Lipids Associated with Genetic Variability in Freezing Tolerance and Cold Acclimation of Solanum Species.

Simultaneous comparisons were made between a freezing-tolerant, cold-acclimating (CA) wild potato species (Solanum commersonii) and a freezing-sensitive, nonacclimating (NA) cultivated species (Solanum tuberosum). Comparative studies allowed differentiation of plasma membrane lipid changes associated with increased freezing tolerance following CA from lipid changes that can result from metabolic adjustment to reduced temperature during CA. Following CA treatment lipid changes found in both the NA and CA species included a decrease in palmitic acid, an increase in unsaturated to saturated fatty acid ratio, an increase in free sterols, an increase in sitosterol, and a slight decrease in cerebrosides. Lipid changes detected only in the acclimating species included an increase in phosphatidylethanolamine, a decrease in sterol to phospholipid ratio, an increase in linoleic acid, a decrease in linolenic acid, and an increase in acylated steryl glycoside to steryl glycoside ratio. These changes were either absent or opposite in the NA species, suggesting an association of these lipid changes with CA. Furthermore, the lipid changes associated with increased freezing tolerance during CA were distinct from lipid differences between the two species in the NA state.

Inheritance of freezing resistance in tuber-bearing Solanum species: evidence for independent genetic control of nonacclimated freezing tolerance and cold acclimation capacity.

Frost or winter survival is regarded as a complex trait with polygenic inheritance. Two major components of this survival in crop plants are freezing tolerance in the nonacclimated state and cold acclimation capacity. To date researchers have not distinguished the two components as separate heritable traits. The mode of inheritance of these two traits was investigated in F1 and backcross populations of two wild diploid potato species (Solanum commersonii and Solanum cardiophyllum) exhibiting extremes of freezing tolerance and acclimation capacity. Precise assessment of these two traits allowed distinction of small but significant differences among genotypes. The two traits were not correlated in segregating populations, suggesting independent genetic control. Analyses of generation means indicate that all of the variance for acclimation capacity and a major proportion of the variance for the nonacclimated freezing tolerance can be best explained by an additive-dominance model with both traits being partially recessive. Recovery of parental phenotypes in limited populations suggests that both traits are controlled by relatively few genes. To our knowledge this is the first study demonstrating independent genetic control of the two main traits associated with frost or winter survival. Our results show that it should be possible to incorporate these traits from wild germ plasm into cultivated crop plants by independent selection. These results help explain the lack of progress in improving winter survival through field selection. Furthermore, our study demonstrates relative simplicity of the inheritance of cold acclimation, thus providing avenues for understanding the link between biochemical and genetic aspects of low-temperature stress in crop plants.

An animal model for pharyngocutaneous fistulas.

Postoperative pharyngocutaneous fistula is not an uncommon complication. Although the frequency of postoperative fistulae has decreased with the use of perioperative broad-spectrum antibiotics, it remains a complication with significant morbidity and expense. We present an animal model for postoperative pharyngocutaneous fistulae based on increasing wound tension. The New Zealand white rabbit was used to assess the rate of wound breakdown in the thyrohyoid membrane. The animals were assigned to one of seven groups according to the width of tissue resected. After tissue resection, the pharyngeal wounds were repaired, as were the overlying skin wounds. Animals were monitored postoperatively up to 14 days, at which time they were killed and underwent autopsy. Statistically significant results were achieved that demonstrate an increasing incidence of pharyngeal wound breakdown associated with increasing width of tissue resected and, therefore, closure tension. The procedure and results will be presented in detail. We propose that this model may be used to assess postoperative wounds as well as substances or methods touted as promoters of wound healing.

Vestibular rehabilitation.

Vestibular dysfunction has many etiologies. Symptoms including vertigo and imbalance may severely hamper life-style, causing the afflicted individual to seek medical attention. For many patients with vestibular complaints a cure is not available. However, the physician is often called upon to relieve incapacitating symptoms. The purpose of this article is to discuss vestibular rehabilitation as a therapeutic modality for patients with chronic vestibular dysfunction.

Eagle's syndrome: the Ochsner experience.

Eagle fully described the syndrome that bears his name in 1948. He noted that the typical patient had undergone tonsillectomy in the past. Although reported in the literature, the carotid artery syndrome is frequently overlooked in patients manifesting craniofacial or pharyngeal pain but who have not undergone tonsillectomy. Cases representative of the variety of patients with Eagle's syndrome treated at the Ochsner Clinic Department of Otolaryngology are presented. The diversity of symptoms and its rather uncommon occurrence often make the diagnosis of Eagle's syndrome elusive. The anatomy and embryology of the stylohyoid complex is discussed, as well as the symptoms, differential diagnosis, workup, and treatment of Eagle's syndrome. We hope to refamiliarize the clinician with this condition in order that it be considered in the assessment of patients with craniofacial pain.

Light chain nephropathy in a 19-month-old boy with AIDS.

A 19-month-old boy with AIDS developed clinically unexplainable proteinuria. Biopsied renal tissue was examined by light microscopy, transmission electron microscopy, and immunofluorescence. Findings included an increase of mesangial matrix with occasional nodular sclerosis, mesangial hypercellularity, and glomerular deposits of kappa and lambda light chains. There were deposits of kappa, but not lambda, light chains in the arteriolar walls, and around the tubular and interstitial capillary basement membranes. Quantitative urinary immunoelectrophoresis revealed an extremely high urinary concentration of kappa light chain. These changes are diagnostic of light chain nephropathy. The rarity of light chain nephropathy in childhood and its occurrence in a patient with AIDS make this case unusual.

Traumatic perforation of the tympanic membrane.

Traumatic perforations of the tympanic membrane are not uncommon injuries. The various etiologies of this injury along with the appropriate evaluation will be discussed. The goal of this review is to enhance the nonotolaryngologist's knowledge of this condition and its treatment.

Macroglossia: a review.

Macroglossia is defined as a resting tongue that protrudes beyond the teeth or alveolar ridge. Complications of macroglossia include articulation errors, mandibular deformities, deglutition difficulties, and airway obstruction. Etiologies include hypothyroidism, the Beckwith-Wiedemann syndrome, lymphangiomatosis, and amyloidosis. Surgical correction of this condition at an early age may prevent or minimize the maxillofacial deformities and speech defects.

Compensatory renal hypertrophy in fetal lambs.

Compensatory renal hypertrophy was studied in fetal lambs during midgestation. Functional adaptation was correlated with anatomica and biochemical changes by measuring glomerular filtration and clearance of para-amino hippurate (PAH). Normal intrauterine body growth and kidney growth by changes in RNA and DNA over a 72-hr period were studied in twin fetuses. Seventy-two hr after left uninephrectomy in single fetuses, there was a significant increase in weight of the renoprival right kidney as well as a significant increase in renal cortical content of RNA and DNA. The rate of increase in RNA was greater than the increase in DNA. Preliminary studies suggest that an increase in renal function parallels renal hypertrophy in fetal lambs.