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1.
Rev Sci Instrum ; 87(11): 11D423, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27910386

ABSTRACT

An extensive set of magnetic diagnostics in DIII-D is aimed at measuring non-axisymmetric "3D" features of tokamak plasmas, with typical amplitudes ∼10-3 to 10-5 of the total magnetic field. We describe hardware and software techniques used at DIII-D to condition the individual signals and analysis to estimate the spatial structure from an ensemble of discrete measurements. Applications of the analysis include detection of non-rotating MHD instabilities, plasma control, and validation of MHD stability and 3D equilibrium models.

2.
Phys Rev Lett ; 114(10): 105001, 2015 Mar 13.
Article in English | MEDLINE | ID: mdl-25815937

ABSTRACT

Density pumpout and edge-localized mode (ELM) suppression by applied n=2 magnetic fields in low-collisionality DIII-D plasmas are shown to be correlated with the magnitude of the plasma response driven on the high-field side (HFS) of the magnetic axis but not the low-field side (LFS) midplane. These distinct responses are a direct measurement of a multimodal magnetic plasma response, with each structure preferentially excited by a different n=2 applied spectrum and preferentially detected on the LFS or HFS. Ideal and resistive magneto-hydrodynamic (MHD) calculations find that the LFS measurement is primarily sensitive to the excitation of stable kink modes, while the HFS measurement is primarily sensitive to resonant currents (whether fully shielding or partially penetrated). The resonant currents are themselves strongly modified by kink excitation, with the optimal applied field pitch for pumpout and ELM suppression significantly differing from equilibrium field alignment.

3.
Phys Rev Lett ; 114(10): 105002, 2015 Mar 13.
Article in English | MEDLINE | ID: mdl-25815938

ABSTRACT

Rapid bifurcations in the plasma response to slowly varying n=2 magnetic fields are observed as the plasma transitions into and out of edge-localized mode (ELM) suppression. The rapid transition to ELM suppression is characterized by an increase in the toroidal rotation and a reduction in the electron pressure gradient at the top of the pedestal that reduces the perpendicular electron flow there to near zero. These events occur simultaneously with an increase in the inner-wall magnetic response. These observations are consistent with strong resonant field penetration of n=2 fields at the onset of ELM suppression, based on extended MHD simulations using measured plasma profiles. Spontaneous transitions into (and out of) ELM suppression with a static applied n=2 field indicate competing mechanisms of screening and penetration of resonant fields near threshold conditions. Magnetic measurements reveal evidence for the unlocking and rotation of tearinglike structures as the plasma transitions out of ELM suppression.

4.
Rev Sci Instrum ; 85(8): 083503, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25173265

ABSTRACT

The DIII-D tokamak magnetic diagnostic system [E. J. Strait, Rev. Sci. Instrum. 77, 023502 (2006)] has been upgraded to significantly expand the measurement of the plasma response to intrinsic and applied non-axisymmetric "3D" fields. The placement and design of 101 additional sensors allow resolution of toroidal mode numbers 1 ≤ n ≤ 3, and poloidal wavelengths smaller than MARS-F, IPEC, and VMEC magnetohydrodynamic model predictions. Small 3D perturbations, relative to the equilibrium field (10(-5) < δB/B0 < 10(-4)), require sub-millimeter fabrication and installation tolerances. This high precision is achieved using electrical discharge machined components, and alignment techniques employing rotary laser levels and a coordinate measurement machine. A 16-bit data acquisition system is used in conjunction with analog signal-processing to recover non-axisymmetric perturbations. Co-located radial and poloidal field measurements allow up to 14.2 cm spatial resolution of poloidal structures (plasma poloidal circumference is ~500 cm). The function of the new system is verified by comparing the rotating tearing mode structure, measured by 14 BP fluctuation sensors, with that measured by the upgraded B(R) saddle loop sensors after the mode locks to the vessel wall. The result is a nearly identical 2/1 helical eigenstructure in both cases.

5.
Acta Chir Orthop Traumatol Cech ; 79(5): 404-10, 2012.
Article in English | MEDLINE | ID: mdl-23140595

ABSTRACT

Locking Compression Plate (LCP) has the advantageous feature that screws can be locked in the plate leaving an angular stable construct. There is no need to have contact between the plate and the bone to achieve stability resulting from friction of the plate-bone-construct. Therefore the plate does not need to be contoured exactly to the bone and the healing bone's periosteal blood supply is not affected. The LCP is used as a bridging plate to gain relative stability in multi-fragmentary, diaphyseal or metaphyseal fractures. Depending on the fracture, the combination hole can also allow the LCP to achieve absolute stability similar to conventional fixation techniques. Osteoporotic fractures have significant impact on morbidity and mortality. Proximal humeral and distal radius fractures are typical examples. These osteoporotic and often comminuted fractures are ideal settings/indications for LCP utilization in the upper extremity. However, the data quality is due to mostly small study populations not so powerful. Unquestionably there has been a clear and fashionable trend to choose operative treatment for these fractures, because the angular stability allows stable fixation and early functional mobilization.


Subject(s)
Arm Injuries/surgery , Bone Plates , Osteoporotic Fractures/surgery , Bone Screws , Female , Fractures, Comminuted/surgery , Humans , Humeral Fractures/surgery , Male , Radius Fractures/surgery , Shoulder Fractures/surgery
6.
Rev Sci Instrum ; 82(3): 033515, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21456744

ABSTRACT

Accurate measurement of internal magnetic field direction using motional Stark effect (MSE) polarimetry in the edge pedestal is desired for nearly all tokamak scenario work. A newly installed 500 kHz 32-channel digitizer on the MSE diagnostic of DIII-D allows full spectral information of the polarimeter signal to be recovered for the first time. Fourier analysis of this data has revealed magnetohydrodynamic (MHD) fluctuations in the plasma edge pedestal at ρ ≥ 0.92. By correlating edge localized mode fluctuations seen on lock-in amplifier outputs with MSE spectrograms, it has been shown that edge pedestal tearing mode fluctuations cause interference with MSE second harmonic instrument frequencies. This interference results in unrecoverable errors in the real-time polarization angle measurement that are more than an order of magnitude larger than typical polarimeter uncertainties. These errors can cause as much as a 38% difference in local q. By using a redundant measure of the linear polarization found at the fourth harmonic photo-elastic modulator (PEM) frequency, MHD interference can be avoided. However, because of poorer signal-to-noise the fourth harmonic signal computed polarization angle shows no improvement over the MHD polluted second harmonics. MHD interference could be avoided in future edge pedestal tokamak polarimeters by utilizing PEMs with higher fundamental frequencies and a greater separation between their frequencies.

7.
Rev Sci Instrum ; 81(10): 10D739, 2010 Oct.
Article in English | MEDLINE | ID: mdl-21033930

ABSTRACT

The use of lock-in amplifiers for phase sensitive detection of motional Stark effect (MSE) diagnostic signals is of critical importance to real-time internal current profile measurements in tokamak plasmas. A digital lock-in (DLI) upgrade utilizing field programable gate array firmware has been installed on the MSE system of the DIII-D tokamak for the eventual replacement of largely obsolete analog units. While the new digital system has shown a small reduction in electronic noise over the analog, the main advantages are reduced cost, hardware simplicity, compact size, and phase tracking during plasma operations. DLI recovery of MSE polarization angles was accomplished through use of reference processing to produce only photoelastic modulator (PEM) second harmonic frequencies and electronic signal processing to maximize the fidelity of the recovered signal. A simplified discrete analytical solution was found that accurately describes the new DLI hardware. The DLI algorithm was found to cause a prohibitively large oscillating artifact atop the demodulated signal. The artifact was caused by the accumulator interval not containing an exact integer number of PEM multiplier periods. Successful MSE measurements require the minimization of this oscillating artifact amplitude. The analytical solution was used to select an appropriate accumulator interval that both reduces the artifact and maintains the greatest temporal resolution possible. Sample EFIT equilibria reconstructions and corresponding safety factor profiles showed very close agreement between the analog and digital lock-ins.

8.
Br J Ophthalmol ; 94(1): 14-9, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20385526

ABSTRACT

OBJECTIVES: The World Health Organization has called upon member states to eliminate blinding trachoma by 2020 using the SAFE strategy. We aimed to determine the prevalence of trachoma and quantify intervention needs for each aspect of the SAFE (surgery, mass administration of antibiotics, promotion of facial cleanliness and environmental improvements) strategy in Nasarawa and Plateau States, Nigeria. METHODS: District-based, household cluster surveys were conducted in all 30 local government areas (LGAs) within the states. RESULTS: A total of 46 960 persons were examined from 7883 selected households. Prevalence estimates of trachomatous inflammation follicular among children 1-9 years of age ranged from 1.7 to 15.8% by LGA. Trichiasis prevalence among adults varied by LGA from 0 to 2.1% and was more common among women (OR = 1.99, 95% CI 1.3 to 3.1). Access to water within a 30 min round trip was reported by 82.3% of households. CONCLUSION: LGA-wide trachoma control interventions are warranted in seven LGAs targeting: 5409 persons for surgery to correct trichiasis, 778 698 persons to receive at least three rounds of mass antibiotic distribution, 855 villages in which to promote face-washing and sanitation, and 102 751 households for latrine construction. These mapping surveys demonstrate an example of evidence-based programme planning necessary for measuring progress towards achieving the GET 2020 objective and can be replicated in other areas yet to be mapped for trachoma.


Subject(s)
Trachoma/epidemiology , Adolescent , Adult , Anti-Bacterial Agents/supply & distribution , Child , Child, Preschool , Family Characteristics , Health Promotion/methods , Health Surveys , Housing/statistics & numerical data , Humans , Infant , Middle Aged , Nigeria/epidemiology , Prevalence , Sanitation/statistics & numerical data , Trachoma/therapy , Young Adult
9.
Lancet ; 375(9710): 231-8, 2010 Jan 16.
Article in English | MEDLINE | ID: mdl-20109924

ABSTRACT

As national programmes respond to the new opportunities presented for scaling up preventive chemotherapy programmes for the coadministration of drugs to target lymphatic filariasis, onchocerciasis, schistosomiasis, soil-transmitted helminthiasis, and trachoma, possible synergies between existing disease-specific policies and protocols need to be examined. In this report we compare present policies for mapping, monitoring, and surveillance for these diseases, drawing attention to both the challenges and opportunities for integration. Although full integration of all elements of mapping, monitoring, and surveillance strategies might not be feasible for the diseases targeted through the preventive chemotherapy approach, there are opportunities for integration, and we present examples of integrated strategies. Finally, if advantage is to be taken of scaled up interventions to address neglected tropical diseases, efforts to develop rapid, inexpensive, and easy-to-use methods, whether disease-specific or integrated, should be increased. We present a framework for development of an integrated monitoring and evaluation system that combines both integrated and disease-specific strategies.


Subject(s)
Developing Countries , Health Policy , Parasitic Diseases/epidemiology , Population Surveillance , Tropical Climate , Elephantiasis, Filarial/diagnosis , Elephantiasis, Filarial/epidemiology , Helminthiasis/diagnosis , Helminthiasis/epidemiology , Helminthiasis/transmission , Humans , Onchocerciasis/diagnosis , Onchocerciasis/epidemiology , Parasitic Diseases/diagnosis , Parasitic Diseases/prevention & control , Schistosomiasis/diagnosis , Schistosomiasis/epidemiology , Trachoma/diagnosis , Trachoma/epidemiology
10.
Trop Med Int Health ; 15(3): 306-11, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20070630

ABSTRACT

OBJECTIVE: After prevalence surveys in all eight regions, Mali started a national programme to control trachoma in 1998. In the sparsely populated desert region of Kidal, where active trachoma prevalence was 46.2% in children under 10, no interventions beyond routine eye-care services were implemented. We estimated the prevalence of trachoma in Kidal, 12 years after baseline mapping surveys, to determine whether interventions to control trachoma were warranted. METHODS: A total of 2165 individuals from 477 households were examined for clinical trachoma signs in a cluster survey using the WHO simplified grading system. Individual and household risk factors for trachoma were assessed. RESULTS: The prevalence of follicular trachomatous inflammation (TF) in children 1-9 years of age was 15.6% (95% CI 11.8-19.5%). Trachomatous trichiasis (TT) was observed in 4 persons for an overall prevalence in all ages of 0.16% (95% CI 0.0-0.35%). Estimated household latrine coverage in the region was 33.1% (95% CI 14.0-52.2%). Residents of 52.8% of surveyed households reported access to a water source outside geographical boundaries of their communities. CONCLUSIONS: In the absence of control interventions, the prevalence of clinical signs of trachoma among children was substantially lower than estimates 12 years earlier. The current prevalence of active trachoma remains above the threshold adopted by WHO, yet there is little evidence of chronic blinding trachoma.


Subject(s)
Trachoma/epidemiology , Child , Child, Preschool , Cluster Analysis , Family Characteristics , Female , Health Surveys , Humans , Infant , Male , Mali/epidemiology , Prevalence , Risk Factors , Surveys and Questionnaires , Toilet Facilities , Trachoma/prevention & control , Water Supply
11.
Rev Sci Instrum ; 79(10): 10F535, 2008 Oct.
Article in English | MEDLINE | ID: mdl-19044677

ABSTRACT

A high-resolution ion Doppler spectrometer (IDS) has been installed on the sustained spheromak plasma experiment to measure ion temperatures and plasma flow. The system is composed of a 1 m focal length Czerny-Turner spectrometer with a diffraction grating line density of 2400 lines/mm, which allows for first order spectra between 300 and 600 nm. A 16-channel photomultiplier tube detection assembly combined with output coupling optics provides a spectral resolution of 0.0126 nm/channel. We calculate in some detail the mapping of curved slit images onto the linear detector array elements. This is important in determining the wavelength resolution and setting the optimum vertical extent of the slit. Also, because of the small wavelength window of the IDS, a miniature fiber-optic survey spectrometer sensitive to a wavelength range 200-1100 nm and having a resolution of 0.2 nm is used to obtain a time-integrated spectrum for each shot to verify specific impurity line radiation. Several measurements validate the systems operation. Doppler broadening of C III 464.72 nm line in the plasma shows time-resolved ion temperatures up to 250 eV for hydrogen discharges, which is consistent with neutral particle energy analyzer measurements. Flow measurements show a sub-Alfvenic plasma flow ranging from 5 to 45 kms for helium discharges.

12.
J Perinatol ; 27(9): 572-8, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17625573

ABSTRACT

OBJECTIVE: To study whether a cue-based clinical pathway for oral feeding initiation and advancement of premature infants would result in earlier achievement of full oral feeding. STUDY DESIGN: Age of achievement of full oral intake was compared for two groups of preterm infants; a prospective study group vs historic cohort controls. Study infants had oral feedings managed by nurses using a clinical pathway that relied on infant behavioral readiness signs to initiate and advance oral feedings. Controls had oral feedings managed by physician orders. RESULT: Fifty-one infants (n=28 study and n=23 control) were studied. Gender distribution, gestational age, birth weight and ventilator days were not different between groups. Study infants reached full oral feedings 6 days earlier than controls (36+/-1 3/7 weeks of postmenstrual age (PMA) vs 36 6/7+/-1 4/7 weeks of PMA, P=0.02). CONCLUSION: The cue-based clinical pathway for oral feeding initiation and advancement of premature infants resulted in earlier achievement of full oral feeding.


Subject(s)
Bottle Feeding , Breast Feeding , Infant, Premature , Case-Control Studies , Critical Pathways , Enteral Nutrition/methods , Female , Gestational Age , Humans , Infant, Newborn , Male , Time Factors
13.
Clin Exp Immunol ; 135(3): 474-7, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15008981

ABSTRACT

UNLABELLED: PspA and PsaA are Streptococcus pneumoniae surface proteins and potential pneumococcal vaccine antigens. The aim of this study was to characterize the transplacental transfer of antibodies to PspA and to PsaA. Paired mother and cord blood sera were obtained at delivery from 28 women. Concentrations of antibodies against PspA, PsaA, tetanus toxoid (vaccine-induced antibodies) and P6-outer membrane protein (OMP) of nontypeable Haemophilus influenzae were determined by ELISA. Antibodies to PspA of the IgG, IgG1 and IgG2 antibodies were also determined. The geometric mean percentage (GM%) of the paired infant:mother antibody were calculated. RESULTS: The GM% of the infant:mother antibody concentrations against PspA, PsaA and P6-OMP antibodies were 64.7% (3.3 micro g/ml in infants vs. 5.1 micro g/ml in mothers), 50.4% (6.8 micro g/ml vs. 13.5 micro g/ml) and 66.7% (5.6 micro g/ml vs. 8.4 micro g/ml), respectively; the GM% of antibodies against tetanus toxoid was 104.5% (4.6 micro g/ml vs. 4.4 micro g/ml). Transplacental transfer of IgG1 was more efficient than that of IgG2 (approximately 120%vs. 65%). A transplacental transfer of antibodies to PspA and to PsaA exist. Moreover, these data suggest an active placental transfer of IgG1 antibodies to PspA since the concentration of these antibodies were consistently higher in cord sera than in the mother's sera.


Subject(s)
Antibodies, Bacterial/blood , Bacterial Proteins/immunology , Carrier Proteins/immunology , Fetal Blood/immunology , Immunity, Maternally-Acquired , Lipoproteins/immunology , Membrane Transport Proteins , Adhesins, Bacterial , Antibodies, Bacterial/immunology , Antigens, Bacterial/immunology , Bacterial Outer Membrane Proteins/immunology , Female , Haemophilus Vaccines/immunology , Humans , Immunoglobulin G/blood , Infant, Newborn , Pregnancy , Streptococcus pneumoniae/immunology , Tetanus Toxoid/immunology
14.
Vaccine ; 14(9): 858-67, 1996 Jun.
Article in English | MEDLINE | ID: mdl-8843627

ABSTRACT

PspA is a surface exposed virulence factor of S. pneumoniae that can elicit protective immunity to pneumococcal sepsis in mice. It can be released from pneumococci by washing them with a solution containing 2% choline chloride, by growing pneumococci in media containing 1.2% choline chloride, or by growing pneumococci in media in which the choline has been replaced by ethanolamine. Our results indicate that PspA is the major protection-eliciting antigen in each of these preparations. Two injections of < or = 1 microgram of native PspA purified by use of a choline-Sepharose column are highly immunogenic in BALB/c and CBA/N mice, and even in the absence of adjuvant can elicit protection against otherwise fatal sepsis with 100 times the LD50 of S. pneumoniae. Fragments comprising the N-terminal 115 and 245 amino acids of PspA were able to elicit protection but only in the presence of complete Freund's adjuvant (CFA). In the absence of CFA the 245 amino acid fragment was less than 1/100 as immunogenic as native PspA.


Subject(s)
Antigens, Surface/immunology , Bacterial Proteins/immunology , Bacterial Vaccines/immunology , Pneumonia, Pneumococcal/prevention & control , Streptococcus pneumoniae/immunology , Animals , Bacterial Proteins/administration & dosage , Drug Evaluation, Preclinical/methods , Injections, Intraperitoneal , Mice , Mice, Inbred BALB C , Mice, Inbred CBA
15.
J Clin Pharmacol ; 35(5): 529-35, 1995 May.
Article in English | MEDLINE | ID: mdl-7657856

ABSTRACT

The effects of famotidine (80 mg per day), cimetidine (1600 mg per day), and placebo on theophylline pharmacokinetic parameters in chronic obstructive pulmonary disease (COPD) patients were compared. This was an open-label, randomized, three-period cross-over study, in which each subject first underwent a seven-day theophylline washout period, and thereafter received three single intravenous doses of theophylline (5 mg/kg infused over 30 minutes) during the study. Each of the experimental treatments was administered orally every 12 hours for a total of 9.5 days (19 doses). Theophylline was infused after the 17th dose of each treatment. Fourteen serial blood samples were collected before the start of each infusion, and for 30 hours after the end of each infusion. Plasma samples were assayed for theophylline, pharmacokinetic parameters were estimated, and treatment effects on each parameter were compared. Fourteen COPD patients completed all three periods of the investigation. Famotidine treatment had virtually no effect on any of theophylline's pharmacokinetic parameters. In contrast, cimetidine treatment significantly altered every pharmacokinetic parameter of theophylline as follows: Cimetidine decreased theophylline geometric mean CL from 2.74 L/h to 2.07 L/h (P < .001), and prolonged theophylline harmonic mean half-life from 6.6 to 9.6 hours (P < .001) and mean residence time from 10.8 to 15.0 hours (P < .001). Cimetidine treatment slightly increased theophylline volume of distribution by approximately 10%, and that change also was statistically significant (P = .032). The authors conclude that the treatment effects of cimetidine on theophylline pharmacokinetic parameters were in accord with those reported by others, and that famotidine treatment had no effect on any of theophylline's pharmacokinetic parameters in COPD patients.


Subject(s)
Cimetidine/pharmacology , Famotidine/pharmacology , Lung Diseases, Obstructive/metabolism , Theophylline/pharmacokinetics , Adult , Aged , Cross-Over Studies , Drug Interactions , Famotidine/therapeutic use , Female , Humans , Infusions, Intravenous , Lung Diseases, Obstructive/drug therapy , Male , Middle Aged , Theophylline/administration & dosage
16.
J Am Diet Assoc ; 95(4): 460-7, 1995 Apr.
Article in English | MEDLINE | ID: mdl-7699189

ABSTRACT

Gestational diabetes mellitus (GDM) is the most common medical disorder complicating pregnancy that requires the services of a registered dietitian. Despite three international workshops on GDM, many questions remain regarding its epidemiology, pathophysiology, screening, diagnosis, and management. Registered dietitians encounter these controversial issues when working with women referred for GDM education and counseling. Nutrition intervention remains the cornerstone of therapy. The purpose of this article is not to provide practice guidelines but to review the literature and current practices in research centers across the United States. Registered dietitians are in a position to individualize nutrition care to each woman's needs and to participate in the decision-making process of nutrition management.


Subject(s)
Diabetes, Gestational/diet therapy , Blood Glucose Self-Monitoring , Counseling , Diabetes, Gestational/diagnosis , Diabetes, Gestational/epidemiology , Diet Records , Dietary Services , Energy Intake , Exercise , Female , Glucose Tolerance Test , Humans , Insulin/therapeutic use , Ketone Bodies/urine , Pregnancy
17.
Otolaryngol Head Neck Surg ; 109(5): 915-25, 1993 Nov.
Article in English | MEDLINE | ID: mdl-8247573

ABSTRACT

Both normal cell turnover and healing of laryngeal and tracheal injuries involve cell migration and mitosis. The proteins that regulate normal cell turnover and wound healing in the larynx and trachea have not been established. It is possible that peptide growth factors, such as transforming growth factor-alpha (TGF alpha) acting through its receptor (EGF/TGF alpha-R), participate in the regulation of these processes. To investigate this hypothesis, we analyzed laryngotracheal cells for TGF alpha protein and receptor in normal and postwounding conditions. TGF alpha protein was detected by immunohistochemical analysis in normal ferret laryngeal and tracheal mucosa. Specific binding to the EGF/TGF alpha receptor in membrane homogenates of ferret larynx and trachea reached saturation after 60 minutes at 37 degrees C, and was effectively displaced by unlabeled epidermal growth factor (EGF) or TGF alpha, but not by unlabeled insulin, angiotensin II, or basic fibroblast growth factor. Scatchard analysis of the specific binding indicated the presence of high-affinity (Kd = 117 pmol) and low-affinity (Kd = 40 nmol) binding sites. The maximum number of available binding sites was 73 fmol/mg protein. Localization of the EGF/TGF alpha receptor by autoradiographic analysis of 125I-EGF binding to sections of normal ferret larynx and trachea revealed EGF/TGF alpha receptors throughout the epithelium, with the highest grain density in the basal layers. Quantitative analysis of autoradiographic grain density between normal, intubated, and extubated animals revealed no significant differences. The presence of TGF alpha protein and its receptor in normal and wounded larynx and trachea supports the hypothesis that these proteins are involved in regulating physiologic responses of laryngotracheal cells.


Subject(s)
ErbB Receptors/analysis , ErbB Receptors/physiology , Ferrets , Larynx/injuries , Trachea/injuries , Transforming Growth Factor alpha/analysis , Transforming Growth Factor alpha/physiology , Wound Healing/physiology , Angiotensin II/analysis , Angiotensin II/physiology , Animals , Autoradiography , Binding Sites , Cell Division/physiology , Cell Movement , Epithelium , ErbB Receptors/chemistry , Fibroblast Growth Factors/analysis , Fibroblast Growth Factors/physiology , Immunohistochemistry , Insulin/analysis , Insulin/physiology , Intubation, Intratracheal , Larynx/cytology , Male , Mitosis , Molecular Weight , Trachea/cytology , Transforming Growth Factor alpha/chemistry , Wounds and Injuries/pathology , Wounds and Injuries/physiopathology
18.
J Pediatr Orthop ; 13(5): 610-4, 1993.
Article in English | MEDLINE | ID: mdl-8376562

ABSTRACT

Review of type and bilaterality of 131 cases (40 bilateral) of slipped capital femoral epiphysis (SCFE) in patients with known endocrinopathies (hypothyroidism, panhypopituitarism, hypogonadism) from 1960 to 1990 showed an increased frequency of patients with endocrine disorders, primarily hypothyroidism (nine of 131 patients, 6.9%); three had bilateral slips; six developed bilateral slips in an average of 11.17 months. Delayed growth plate closure is common in SCFE. Because hypothyroidism can be easily overlooked, all patients with SCFE should be screened for hypothyroidism by measuring serum T4 and TSH (such screening is inexpensive (r = $60). Pituitary deficiency should be considered in children short for their age who have hypogonadism. Any child with a unilateral slip and one of these endocrine deficiencies has a high risk of subsequent bilateral involvement. Prophylactic pinning of the uninvolved hip is recommended because 100% of our patients eventually had bilateral slips.


Subject(s)
Endocrine System Diseases/complications , Epiphyses, Slipped/complications , Femur Head , Adolescent , Adult , Child , Epiphyses, Slipped/diagnostic imaging , Female , Humans , Hypogonadism/complications , Hypoparathyroidism/complications , Hypopituitarism/complications , Hypothyroidism/complications , Male , Radiography
19.
Drug Metab Dispos ; 20(6): 869-76, 1992.
Article in English | MEDLINE | ID: mdl-1283569

ABSTRACT

L-696,229 is a potent and specific inhibitor of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase and is currently undergoing clinical evaluation. In vivo metabolism in rats was investigated using an intravenous bolus dose of 5 mg/kg [3H]L-696,229. The amount of radioactivity eliminated in bile and urine over a period of 6 hr was 60 and 22%, respectively. Radiochromatographic analysis of the bile and urine showed that L-696,229 was metabolized rapidly and completely to several common metabolites. Sequential oxidation at the alpha-position of the 5-ethyl group to an acetyl moiety, aromatic hydroxylation of the benzoxazole group (position C4', C6', or C7'), and subsequent sulfate conjugation were the major metabolic pathways as determined by the application of enzymatic hydrolysis, FAB-MS, and 1H- and 13C-NMR spectroscopies. The in vitro metabolism of this 2-pyridinone derivative with rat liver slices resulted primarily in hydroxylation at the 6-methyl and 5-ethyl groups. The 6-hydroxymethyl- and 5-alpha-hydroxyethyl analogs were also inhibitors of HIV-1 reverse transcriptase.


Subject(s)
Antiviral Agents/pharmacokinetics , Benzoxazoles/pharmacokinetics , HIV-1/enzymology , Liver/metabolism , Pyridones/pharmacokinetics , Reverse Transcriptase Inhibitors , Animals , HIV Reverse Transcriptase , HIV-1/drug effects , In Vitro Techniques , Male , Rats , Rats, Sprague-Dawley
20.
Spine (Phila Pa 1976) ; 17(6 Suppl): S109-16, 1992 Jun.
Article in English | MEDLINE | ID: mdl-1631709

ABSTRACT

The purpose of this study was to determine the incidence of intraspinal pathology presenting as idiopathic scoliosis in children less than 11 years of age and otherwise neurologically normal. Twenty-six consecutive patients (5 boys, 21 girls) with idiopathic scoliosis measuring at least 15 degrees were studied with magnetic resonance imaging. Five children (19.2%) were diagnosed by magnetic resonance imaging to have Chiari-I malformations with hydromyelia (two patients), syringomelia (one patient), intramedullary tumor (one patient) and terminal lipoma (one patient). Only two of the five patients had left thoracic curves. Intramedullary spinal cord pathology can present as scoliosis without neurologic signs. Scoliosis can be the initial neurologic sign suggesting intraspinal pathology, and magnetic resonance imaging is indicated in routine evaluation of children less than 11 years of age.


Subject(s)
Arnold-Chiari Malformation/diagnosis , Magnetic Resonance Imaging , Scoliosis/diagnosis , Spinal Cord Diseases/diagnosis , Arnold-Chiari Malformation/complications , Arnold-Chiari Malformation/epidemiology , Child , Female , Humans , Incidence , Male , Scoliosis/etiology , Spinal Cord Diseases/complications , Spinal Cord Diseases/epidemiology
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