Modified Mitchellson endoscope holder

Mitchellson's ear speculum holder has been modified to act as an endoscope holder, in order to be used in endoscopic surgery of the nose or ear.

Effects of temperature changes on nasal patency

INTRODUCTION

This study aims to assess the difference in nasal patency and resistance to temperature changes objectively and subjectively.

METHODS

This cross-sectional study involved 50 subjects without nasal obstruction. All these subjects were given a questionnaire to determine nasal obstruction subjectively on a visual analogue scale. Acoustic rhinometry was performed in all these subjects for objective measurement of nasal obstruction. The study was conducted in two separate rooms in the departmental laboratory where the temperatures were maintained at 30-33 degrees Celsius and an air-conditioned room at 18-22 degrees Celsius, respectively.

RESULTS

The objective measurement to two different temperature exposures showed differences in nasal patency and resistance. There was an increase in nasal resistance and a decrease in nasal patency to air-conditioned air compared to room temperature air. Subjective assessment also showed significant correlation to the two temperature exposures. However, independent sample test only showed significant difference in the subjective questionnaire (p-value equals 0.001). Objective acoustic rhinometry did not show significant difference.

CONCLUSION

There is no significant difference in objective acoustic rhinometry with regard to nasal resistance and patency with environmental temperature changes in the tropics.

Real-time cerebral angiography: sensitivity of a new contrast-specific ultrasound technique

BACKGROUND AND PURPOSE

To test a new contrast-specific sonography imaging method that offers visualization of the intracranial vasculature in a manner similar to that seen on angiography.

MATERIALS AND METHODS

Thirty patients (35 sonography studies total) were included in the study after they provided written informed consent. The patients were scanned through the temporal bone window from both sides after intravenous injection of an ultrasound contrast agent (UCA; perflexane lipid microspheres [Imagent]). The goal was to visualize the intracranial arteries, including the middle (M1-M3), anterior (A1 and A2), and posterior (P1-P3) cerebral arteries, using an axial scanning plane. The studies were performed using a contrast-specific imaging mode, based on a phase inversion technique (transcranial ultrasound angiography [tUSA]). For sensitivity, the results were compared with x-ray angiography as the "gold standard." For interobserver reliability, 24 of 35 sonography studies were evaluated by 2 physicians with little training in transcranial sonography and by a seasoned sonographer.

RESULTS

The sensitivity of tUSA ranged between 0.778 (95% confidence interval [CI] of 0.577-0.914) and 0.963 (95% CI of 0.810-0.999). The sensitivities were similar among physicians with little training in transcranial sonography and the seasoned sonographer, indicating high inter-rater reliability. Overall, tUSA provided high anatomic resolution and vascular delineation even of small vessels in the millimeter range. At peak intensity, no UCA-related artifacts were observed.

CONCLUSION

tUSA provides images of the intracranial arteries similar to those obtained at angiography with high anatomic resolution, reasonable sensitivity, and interobserver reliability.

Epithelial Migration in Open Mastoidectomy Cavities

OBJECTIVE

To study the rate and pattern of epithelial migration in 18 dry, open mastoidectomy cavities.

METHODS

This was a prospective study of 19 patients who had undergone mastoidectomy at a secondary (state) hospital and a tertiary referral centre at least 6 months previously and whose mastoid cavities were dry and not infected. Their mastoidectomy cavities were cleaned and India ink dots applied in its medial aspect under microscope. The patients were followed up at 1 or 2 weekly intervals for a minimum of 3 months or until the dots disappeared, whichever came first. On follow-up, the cavities were examined under microscope. If migration was observed, the rate and pattern were noted.

RESULTS

Most (94.4%) of the cavities were noted to have epithelial migration laterally. No migration was observed in 5.6%. The start of migration of ink dots was noted in the 2nd week in 53% of the cavities, with a mean of 3.05 weeks. The mean rate of migration was 0.68 mm/week.

CONCLUSION

Epithelial migration appears to be predominantly lateral (94.4%), with onset in the 2nd week (53%) at a rate of 0.68 mm/week. Epithelial migration might not play an important role in accumulation of wax in open mastoidectomy cavities.

Efficient generation of closed magnetic flux surfaces in a large spherical tokamak using coaxial helicity injection

A method of coaxial helicity injection has successfully produced a closed flux current without the use of the central solenoid in the NSTX device, on a size scale closer to a spherical torus reactor, for a proof-of-principle demonstration of this concept. For the first time, a remarkable 60 times current multiplication factor was achieved. Grad-Shafranov plasma equilibrium reconstructions are used to verify the existence of closed flux current. In some discharges the generated current persists for a surprisingly long time approximately 400 ms.

Plasma homocysteine and total thiol content in patients with exudative age-related macular degeneration

PURPOSE

Exudative age-related macular degeneration (ARMD) is one of the debilitating ocular complications, which results in permanent blindness. Elevated homocysteine (Hcys) levels have been associated in the development of several vascular diseases. Vascular and oxidative stress theories have been implicated for the development of choroidal neovascularization in exudative ARMD. The aim of the present study was to investigate the possible role of plasma Hcys and thiol content (tSH) as a risk factor for the development of exudative ARMD.

METHOD

A total of 16 patients with exudative ARMD and 20 age-matched controls were recruited for the study. Plasma Hcys levels were analysed using Reverse Phase High Performance Liquid Chromatography. Plasma glutathione (GSH) content was determined using o-phthalaldehyde (OPA) derivatization and subsequent detection by fluorimeter. Plasma tSH levels were determined by using thiol-specific reagent dithionitrobenzoic acid (DTNB) spectrophotometrically.

RESULTS

Plasma Hcys levels in exudative ARMD were elevated three-fold (18+/-5.0 microM) when compared to healthy controls (6.7+/-1.8 microM). There was a two-fold decrease in the GSH and tSH in exudative ARMD when compared with controls. Negative correlation was observed between diminished tSH and Hcys levels (r=-0.4837, P=0.05). Similarly plasma Hcys levels negatively correlated with GSH content (r=-0.6620, P<0.05).

CONCLUSION

Results from our present study revealed that there is an elevated Hcys level and diminished thiol pool content in exudative ARMD that are significant.

Reliability of a tympanic thermometer in measuring temperatures in children after minor ear surgery

AIM

To evaluate the reliability of infrared tympanic thermometry in children who have undergone myringotomy with grommet insertion.

METHOD

Forty children who had undergone myringotomy with at least one grommet insertion had the tympanic temperature of each ear and the axillary temperature measured on admission and 30 minutes post-operatively.

RESULT

No difference was found between the pre- and post-operative temperatures measured by either method (p > 0.05, paired t-test, hypothesized difference of 0).

CONCLUSION

Infrared tympanic thermometry is reliable in monitoring body temperature in children who have had minor ear surgery.

Comparative study of bacteriology in recurrent tonsillitis among children and adults

INTRODUCTION

Diagnosis and treatment of acute tonsillitis are one of the most common problems seen at an otorhinolaryngology clinic in both adult and paediatric populations. Much has been written about bacteriology of recurrent tonsillitis but it remains a controversial topic. Despite the fact that tonsillitis is so common, consensus seems to be lacking as to the main causative organism and the differences between children and adults. The tonsillar core bacteriology of 233 patients with recurrent tonsillitis who underwent tonsillectomy from January 2000 to June 2003 is presented.

METHODS

The patient population was divided into two groups, namely: the paediatric group and the adult group. 132 patients, whose age was more than 12 years, were in the adult group. 101 patients aged between two and 12 years, were in the paediatric group. The bacteriology of the children and adults were tabulated according to their species, and were compared.

RESULTS

138 patients grew single pathogenic bacteria in their tonsillar core culture, 52 grew two different pathogenic bacteria, and the rest (43) grew normal bacterial flora. Staphylococcus aureus was the most commonly-isolated bacterium and accounted for 40.9 percent of the total cultures isolated; its prevalence was the same in the adults and children. Beta-haemolytic Streptococcus was isolated in 23 percent of subjects, and was predominantly from group A (Streptococcus pyogens). Group A beta-haemolytic Streptococci was more prevalent in children. Pseudomonas aeruginosa, which rarely cause pathogenicity in tonsils, was cultured from nine (3.8 percent) of our study subjects.

CONCLUSION

This study showed that Staphylococcus aureus is the most common pathogenic bacteria cultured both in adults and children. Klebsiella pneumonia, Streptococcus pneumonia, Escherichia coli and Enterobacter are more prevalent in adults. Haemophilus influenza and Streptococcus pyogens are more prevalent in children. Pseudomonas aeruginosa is not a rare causative organism in recurrent tonsillitis. Since the mechanism of activation of infection in recurrent tonsillitis is unknown, knowing the bacteriology does not help us to treat the disease. However, it may be a stepping stone to eventually understanding whether the bacteria play a role in reactivating recurrent infections. From previous and current studies, there is no relationship between bacteriology and recurrent infections.

Prospective reliability of the STRokE DOC wireless/site independent telemedicine system

The authors evaluated a site-independent telemedicine system. Telemedicine may be limited by the need for fixed connectivity. Wireless and site-independent technologies eliminate this limitation. Twenty-five stroke patients underwent evaluations by remote and bedside examiners. Ten of 15 (67%) NIH Stroke Scale and 9 of 11 (82%) Modified NIH Stroke Scale items showed excellent interrater reliability. Spearman correlations were > or =0.93. This Internet system is reliable and valid. Further studies should assess its use in acute stroke.

Tracheal stent in the treatment of tracheal stenosis

The use of airway stents for the treatment of benign airway stenosis is increasingly advocated. However, the long-term safety and efficiency of these devices has not been established. We present a case of tracheal stenosis. which persisted despite open surgical and laser correction. The patient required tracheal stent insertion and is currently well with no respiratory difficulty. The use of metallic or silicon intraluminal stent remains appropriate in cases in which there is defined and relative short-term end point of treatment.

Large vestibular aqueduct syndrome

Large Vestibular Aqueduct Syndrome is a congenital malformation of the temporal bone characterised by early onset of sensorineural hearing loss and vestibular disturbance. Familial large vestibular aqueduct syndrome suggests autosomal recessive or X-linked inheritance and accounts for non-syndromic sensorineural hearing loss in these patients.

Delayed complication of radiotherapy: laryngeal fibrosis and bilateral vocal cord immobility

Radiotherapy is the accepted treatment for early laryngeal carcinomas with the advantage of voice preservation. It is however, not without complications. We report a case of bilateral vocal cord immobility 15 years after radiotherapy. This appears to be due to ankylosis of cricoarytenoid joint and fibrosis of the larynx.

Revision of cemented hip arthroplasty using a hydroxyapatite-ceramic-coated femoral component

We report the clinical and radiological outcome of 86 revisions of cemented hip arthroplasties using JRI-Furlong hydroxyapatite-ceramic-coated acetabular and femoral components. The acetabular component was revised in 62 hips and the femoral component in all hips. The mean follow-up was 12.6 years and no patient was lost to follow-up.

The mean age of the patients was 71.2 years. The mean Harris hip and Oxford scores were 82 (59 to 96) and 23.4 (14 to 40), respectively. The mean Charnley modification of the Merle d’Aubigné and Postel score was 5 (3 to 6) for pain, 4.9 (3 to 6) for movement and 4.4 (3 to 6) for mobility. Migration of the acetabular component was seen in two hips and the mean acetabular inclination was 42.6°. The mean linear polyethylene wear was 0.05 mm/year. The mean subsidence of the femoral component was 1.9 mm and stress shielding was seen in 23 (28%) with bony ingrowth in 76 (94%). Heterotopic ossification was seen in 12 hips (15%). There were three re-revisions, two for deep sepsis and one for recurrent dislocation and there were no re-revisions for aseptic loosening. The mean EuroQol EQ-5D description scores and health thermometer scores were 0.69 (0.51 to 0.89) and 79 (54 to 95), respectively. With an end-point of definite or probable loosening, the probability of survival at 12 years was 93.9% and 95.6% for the acetabular and femoral components, respectively. Overall survival at 12 years, with removal or further revision of either component for any reason as the end-point, was 92.3%.

Our study supports the continued use of this arthroplasty and documents the durability of hydroxyapatite-ceramic-coated components.

Double-crush syndrome after acetabular fractures. A sign of poor prognosis

Injury to the sciatic nerve is one of the more serious complications of acetabular fracture and traumatic dislocation of the hip, both in the short and long term. We have reviewed prospectively patients, treated in our unit, for acetabular fractures who had concomitant injury to the sciatic nerve, with the aim of predicting the functional outcome after these injuries. Of 136 patients who underwent stabilisation of acetabular fractures, there were 27 (19.9%) with neurological injury. At initial presentation, 13 patients had a complete foot-drop, ten had weakness of the foot and four had burning pain and altered sensation over the dorsum of the foot. Serial electromyography (EMG) studies were performed and the degree of functional recovery was monitored using the grading system of the Medical Research Council. In nine patients with a foot-drop, there was evidence of a proximal acetabular (sciatic) and a distal knee (neck of fibula) nerve lesion, the double-crush syndrome. At the final follow-up, clinical examination and EMG studies showed full recovery in five of the ten patients with initial muscle weakness, and complete resolution in all four patients with sensory symptoms (burning pain and hyperaesthesia). There was improvement of functional capacity (motor and sensory) in two patients who presented initially with complete foot-drop. In the remaining 11 with foot-drop at presentation, including all nine with the double-crush lesion, there was no improvement in function at a mean follow-up of 4.3 years.

Glomus tympanicum: a report of two cases

Two cases of glomus tympanium tumor of the middle ear stage 'type A' according to Fisch classification, are presented due to their rarity in this part of the world. These tumors were excised by end aural tympanotomy approach and there has been no recurrence in both patients to date.

Oropharyngeal flora changes in patients with head and neck malignancy post radiotherapy

Radiotherapy has been recognized as a valuable modality of treatment in the management of head and neck cancers. It can have a direct bactericidal effect on the normal flora of the oropharynx. The objective of this study is to determine the changes in the oropharyngeal flora after external beam radiation. This prospective non randomized control study was performed to aid in identification of organisms involved in sepsis, as well as aid in choosing appropriate antibiotics for surgical procedures in irradiated patient. Forty patients with various head and neck malignancy and thirty control patients were selected. Oropharyngeal swabs were taken prior to radiotherapy, at the end and one month after radiotherapy. A single swab was taken from the control group. A full bacteriological analysis was performed. There was a statistically significant decrease in Alpha Hemolytic Streptococci and Neisseria species post radiotherapy. B Proteus and Candida Albicans showed a statistical significant increase in patients with head and neck cancer post radiotherapy. These changes remained even one month after radiotherapy.

Actinomyces infection of the mastoid: a rare entity

A rare case of mastoid infection caused by actinomyces israelii is presented. This patient underwent exploratory mastoidectomy followed by long term oral pencillin. She responded well to the treatment and has been asymptomatic on follow up to date.

Nocardia infection of the mastoid in an immunocompromised patient

A rare case of Nocardia infection of mastoid is presented in an immunocompromised patient.

Ocular presentation of sphenoid mucocele

A sphenoid mucocele often presents late due to its deep-seated anatomical site. It has a varied presentation, due to its close relationship to the cavernous sinus and the base of the skull. It can present initially to the ophthalmologist with ocular complaints. In the present paper, the authors present two cases of sphenoid mucocele, one with an isolated third and one with an isolated sixth cranial nerve palsy.

Idiopathic cases of male infertility from a region in India show low incidence of Y-chromosome microdeletion

Chromosomal and Y-chromosomal microdeletion analysis has been done in cases of idiopathic infertility with the objective of evaluating the frequency of chromosomal and molecular anomaly as the causal factor of infertility. Barring a few cases of Klinefelter syndrome (XXY or XY/XXY mosaics), no chromosomal anomaly was encountered. Y-microdeletion was analysed by PCR-screening of STSs from different regions of the AZF (AZFa, AZFb, AZFc) on the long arm of the Y, as well as by using DNA probes of the genes RBM, DAZ (Yq), DAZLA (an autosomal homologue of DAZ) and SRY (Yp; sex determining gene). Out of 177 cases examined, 9 (azoospermia - 8 and oligoasthenospermia - 1) showed partial deletion of AZF. The size of deletion varied among patients but AZFc was either totally or partially removed in all of them. In contrast, no deletion was detected in AZFa. Testis biopsy done on a limited number of cases (50) showed diverse stages of spermatogenic arrest with no specific correlation with the genotype. The frequency of Y-chromosome microdeletion in our samples (approximately 5%) is much lower than the frequency (approximately 10%) reported globally and the two previous reports from India. We contend that the frequency may be affected by population structures in different geographical regions.

Cytological evaluation of global DNA methylation in mouse testicular genome

Global methylation of DNA from different testicular cell types has been studied by DNA end-labeling and nick translation of fixed chromatin (in situ), following digestion with cytosine methylation-sensitive restriction enzymes. Both at the level of chromatic (chromosome) and naked DNA, there is extensive methylation of the genome. Although the extent of methylation was nearly the same among different cell types in the MspI, HpaII, and HhaI digested end-labelled DNA, in the chromosome preparations the digestion patterns varied in cell type-specific manner, pachytene being the most sensitive and spermatids and sperm the most resistant. The differential sensitivity is attributable to the difference in the chromatin organisation in different testicular cell types though no specific region could be identified as particularly more sensitive or resistant to the enzymes. Pachytene bivalents do not reveal a consistent segmental pattern of digestion, but the perichiasmate regions of diplotene/diakinesis and metaphase I chromosomes show hypersensitivity to the enzymes.

Attrition and non-compliance in secondary stroke prevention trials

BACKGROUND

Attrition and non-compliance of subjects in secondary stroke prevention trials due to study drug-induced adverse events and loss to follow-up could lead to bias and loss of information, thus affecting the analysis of study results.

METHODS

We reviewed results from ten antiplatelet stroke prevention clinical trials: CAN TIA, DUTCH TIA, SWED ASA, SALT, UK TIA, CATS, TASS, ESPS, ESPS-2, and CAPRIE to tabulate the frequencies for total subject discontinuation, voluntary withdrawal, and loss to follow-up.

RESULTS

Forty thousand seven hundred and thirty (40,730) subjects participated in the aforementioned secondary stroke prevention trials. The range of outcomes was 11.8-52.0% for subjects discontinued for any reason (n = 9 trials); 3.0-20.9% for study drug-induced adverse events (n = 9 trials), and 4.2-7.8% for voluntary withdrawal (n = 10 trials).

CONCLUSION

There is a substantial discrepancy (up to 20%) between the frequencies of total subject discontinuation for any reason and the sum of study drug-induced adverse events, voluntary withdrawal and loss to follow-up. Underestimation of these important outcomes may limit the ability of clinicians to translate results from clinical trials into medical practice.

Isomerism of the right atrial appendages: clinical, anatomical, and microscopic study of a long-surviving case with asplenia and ciliary abnormalities

This study describes a case of isomerism of the right atrial appendages (bilateral morphologically right atrial appendages associated with complex congenital cardiac lesions) with ciliary abnormalities. Detailed investigation included gross anatomic dissection, review of the clinical history, and light, confocal, and electron microscopy. Clinically, this 40-year-old, long-surviving male patient had relatively good health until 4 years before death, which was due to cardiac failure. Surgical intervention consisted only of a Blalock-Taussig shunt (anastomosis of the right subclavian artery to the right pulmonary artery) at 6 years of age. Despite the presence of complex cardiac malformations and asplenia, his longevity may be attributed to the connection of the pulmonary veins to the atrium without pulmonary venous obstruction, pulmonary valvar stenosis rather than atresia, no significant atrioventricular valve regurgitation, and no serious infections during his life. Microscopic examination of bronchial epithelium revealed a narrow, disorganized epithelium with abundant goblet cells and short, angulated cilia with a random orientation and possibly an abnormal central microtubule doublet. These abnormalities were not present in controls, and have been noted in primary ciliary dyskinesia (PCD) or Kartagener's syndrome. Because this syndrome has classically been thought to cause random lateralization resulting in a mirror-imaged arrangement of the organs, the occurrence of truly isomeric patterns is not widely recognized. Whereas polysplenia and left bronchial isomerism have been reported to occur in immotile cilia syndrome, this is the first report to present detailed postmortem anatomic evidence of isomerism of the right atrial appendages, right bronchial isomerism, and asplenia in association with microscopy suggesting ciliary abnormalities.

Demonstration of plasma startup by coaxial helicity injection

The first successful results on the transfer of a coaxial helicity injection (CHI) produced discharge to inductive operation are reported. CHI-assisted plasma startup is more robust than inductive only operation. After hand off for inductive operation, the initial 90 kA of CHI-produced current drops to 40 kA, then ramps up to 170 kA, using only 30 mV s, more than 30% higher than that produced by induction alone. These significant performance enhancing results were obtained on the HIT-II spherical torus experiment (major/minor radius of 0.3/0.2 m).

Awareness, treatment, and control of vascular risk factors in African Americans with stroke

OBJECTIVE

To investigate control of risk factors in African American patients with previous stroke.

METHODS

The baseline history, physical examination, and laboratory data for 1,086 subjects enrolled in the African American Antiplatelet Stroke Prevention Study from 1995 to 1999 were studied. The level of awareness, pharmacologic treatment, and control of diabetes mellitus (casual plasma glucose level > or =200 mg/dL), hypertension (blood pressure > or =140/90 mm Hg), and hypercholesterolemia (serum total cholesterol level > or =240 mg/dL) were determined.

RESULTS

Forty percent of subjects reported a history of diabetes mellitus or use of diabetic medication, and 2% of the remaining subjects had a serum glucose level of > or =200 mg/dL. Of those subjects known to be diabetic, 33% had a serum glucose level of > or =200 mg/dL. A history of hypertension or use of antihypertensive medication was reported in 87% of subjects, and 48% of the remaining subjects were found to have a blood pressure of > or =140/90 mm Hg on exam. Of those subjects known to be hypertensive by history, 73% were on antihypertensive medication, but only 30% of the treated subjects had a blood pressure under 140/90 mm Hg. A history of hypercholesterolemia or use of a lipid-lowering agent was reported in 40% of subjects, and 24% of the remaining subjects had a cholesterol level of > or =240 mg/dL. Use of a lipid-lowering agent was reported in 43% of subjects known to be hypercholesterolemic, and 38% of the hypercholesterolemic subjects had a cholesterol level of > or =240 mg/dL.

CONCLUSION

Inadequate rates of awareness and control of cardiovascular disease and stroke risk factors are seen in a clinical trial of African American stroke patients and are comparable with those of previously published reports.

Mapping and QTL analysis of the barley population Sloop × Halcyon

A genetic linkage map of Hordeum vulgare L. 1280 cM in length, composed of 257 AFLP, RFLP, SNP, and microsatellite markers, has been constructed. The map was based on a doubled haploid population made from the cross Sloop (spring type) × Halcyon (winter type). The genetic map was used to identify qualitative major genes and quantitative trait loci (QTLs) affecting traits related to growth and flowering, grain colour, and disease resistance. Nine QTLs associated with grain colour (brightness, redness, yellowness, blue aleurone colour), plant height, 'intrinsic lateness', awn emergence, response to photoperiod, and spring or winter habit were located on 1H, 2H, 3H, 4H, and 5H. Eight QTLs associated with resistance to scald, net form of net blotch, leaf rust and powdery mildew were identified on chromosomes 1H, 2H, 3H, 4H, 5H, and 7H. The estimated magnitude of the QTL effects ranged from 9 to 85% of the total phenotypic variance. Resistances to leaf scald, net blotch, and leaf rust, and photoperiod and grain colour, were each controlled by at least one major gene.

Mapping of genomic regions associated with net form of netblotch resistance in barley

Quantitative trait loci (QTLs) associated with resistance to net blotch and their chromosomal locations were determined from analyses of doubled haploid progeny of Alexis/Sloop, Arapiles/Franklin, Sloop/Halcyon, and recombinant inbred lines of Sloop-sib/Alexis. Five QTLs on chromosomes 2H, 3H, and 4H were found to be associated with seedling resistance to the net form of net blotch. In Arapiles/Franklin and Alexis/Sloop populations, 4 significant QTLs explaining 9–17% of the variation in net blotch resistance were detected on 2H and 3H. A major locus, QRpts4L accounting for 64% of the variation in infection type, was detected on 4H in the Sloop/Halcyon population. In Sloop/Halcyon, 2 microsatellite markers, EBmac0906 and GMS089, and AFLP marker P13/M50-108, co-segregated and detected maximum variability for net blotch resistance as revealed by bootstrap analysis. EBmac0906 and Bmac0181 were validated in F2 progeny of an Ant29/Halcyon population and reliably predicted phenotypes of 93% of lines resistant and susceptible to net blotch. These markers may be used within breeding programs to select alleles favourable for net blotch resistance derived from Halcyon.

Development and allele diversity of microsatellite markers linked to the aluminium tolerance gene Alp in barley

Aluminium (Al) toxicity is one of the main factors restricting barley production in acidic soils. The utilisation of barley cultivars tolerant to Al is one of the most economic strategies for expanding barley production in these soils. Among barley genotypes, the cultivar Dayton has been reported to exhibit the highest level of Al tolerance. The gene conferring Al tolerance in Dayton, Alp, has been mapped to the long arm of chromosome 4H using RFLP markers. However, such markers are not useful for routine marker-assisted selection in breeding programs due to the cost and labour associated with their use. To increase the ease by which marker-assisted selection can be conducted for Alp, we sought to identify microsatellite markers linked to this gene. Several such markers that flank Alp were identified in a mapping population from a cross between Dayton and Harlan Hybrid. The most tightly linked microsatellite markers, HVM68 and Bmag353, flank Alp and are 5.3 cM and 3.1 cM from this locus, respectively. The linkage between Bmag353 and Alp was validated in a separate F3 population derived from the cross between Dayton and F6ant28B48-16, where this microsatellite marker was found to predict the Al tolerance phenotype with over 95% accuracy. Allele diversity for the 3 most tightly linked microsatellite markers was evaluated among 40 barley genotypes currently used in Australian barley breeding programs. The high levels of polymorphism detected among the genotypes with the markers indicated that the microsatellite markers, especially Bmag353 and Bmac310, will be broadly useful for marker-assisted selection of Alp in breeding programs seeking to improve Al tolerance.

Otological disorders in Down's Syndrome

OBJECTIVE

To assess if children with Down's Syndrome have a higher prevalence of otological abnormality compared to their normal counterparts in Malaysia.

METHODOLOGY

Thirty children with Down's Syndrome and normal children underwent otoscopic ear examination and Impedance test in the ENT outpatients clinic in University Hospital, Kuala Lumpur, Malaysia.

RESULTS

The study showed that children with Down's Syndrome had higher otological disorders. Forty four percent had impacted wax compared to 14.4% in normal children. Twenty one percent of ears in the study group had retracted drums compared to 6.6% of control. Fifteen percent of ears in the study group had middle ear effusion compared to 3.4% in controls, 55% had a type B tympanogram compared to 8.3% in controls and 73.4% had auditory canal stenosis compared to 14.4% in controls.

CONCLUSION

Children with Down's Syndrome, thus have a higher incidence of otological disorders.

Hangman's knot in securing bypass tubes in endonasal dacryocystorhinostomy

We performed 15 cases of dacryocystorhinostomy endoscopically with an 86% success rate. Using a Hangman's knot, the bypass tubes were placed in a secure and lasting way.

Gender and pramipexole effects on levodopa pharmacokinetics and pharmacodynamics

The authors studied the pharmacokinetics of levodopa (LD) with and without pramipexole (PPX) in men and postmenopausal women with PD. Patients on stable dose of carbidopa/LD were randomized to receive escalating doses of placebo or PPX over 7 weeks. LD and PPX pharmacokinetics were performed after a single test dose 25/100 of carbidopa/LD, before initiation of PPX or placebo, at 1.5 mg/d and 4.5 mg/d of PPX or placebo. Compared to men, women had greater LD bioavailability. PPX did not alter LD bioavailability, and PPX pharmacokinetics were equivalent in men and women.

Prospective longitudinal assessment of hallucinations in Parkinson's disease

OBJECTIVE

To monitor the evolution of hallucinations over 4 years in a stratified sample of patients with PD.

METHODS

Using a modified version of the Unified PD Rating Scale (UPDRS) Thought Disorder question, the authors stratified patients into five baseline behavioral groups. They recruited up to 20 patients for each group to participate in sequential interviews (Rush Hallucination Inventory) at baseline and 6, 18, and 48 months. UPDRS motor examinations and Mini Mental State Examinations (MMSE) were obtained at baseline and 48 months. Data were analyzed with Wilcoxon rank sum tests, Mantel-Haenszel tests, and Spearman correlations. To determine features that influenced the new development of hallucinations, a cumulative logit regression model of hallucination severity over time was fit using generalized estimating equations.

RESULTS

Based on the design stratification, 60 patients had no hallucinations at baseline (20 with no behavioral problems, 20 with sleep fragmentation, 20 with altered dream phenomena). Twenty-nine patients had hallucinations (20 with retained insight and 9 with loss of insight). At 48 months, the authors could account for all but two subjects (98% retrieval). In 4 years, the presence of hallucinations increased (33% at baseline, 44% at 18 months, and 63% at 48 months, p < 0.0001). The presence of frequent hallucinations (at least three times weekly) also increased (p = 0.0002). Having hallucinations at baseline or at any given assessment was a strong predictor at all follow-up evaluations of continued hallucinations (p < 0.0001). Hallucinations were not associated with increased mortality (chi(2) = 0.59, df (1), p = 0.47). Among the 60 subjects without hallucinations at baseline, time was the only significant factor influencing the development of hallucination over 48 months. Baseline age, PD duration, sex, medications, and UPDRS or MMSE scores did not influence the incidence of hallucinations.

CONCLUSIONS

This prospective, longitudinal study documents the persistent and progressive nature of hallucinations in PD patients on chronic dopaminergic therapy. The consistent association of hallucinations with combined levodopa/agonist therapy suggests that these drugs may play a role in the pathophysiology of hallucinations.

A pilot survey of African-American physician perceptions about clinical trials

African Americans have been underrepresented in clinical trials. However, African-American physician attitudes about clinical trials may influence patient recruitment. We identified the perceptions of African-American physician members of the Cook County Physicians Association (CCPA) about clinical trials in the Chicago Metropolitan area using a self-administered questionnaire. An 18-item, 2-page survey that included information about physician demographics, practice type, and specialty, and perceptions regarding clinical research was sent to each of the 609 active or inactive members of the CCPA, a predominantly African-American physician organization. Each survey was accompanied by a letter of explanation and a self-addressed, return envelope. Data from the surveys were stored and analyzed in a database. A total of 166 members (27%) completed the survey. Fifty percent of the respondents were men and 50% were women. The mean age of the group was 45 years, and almost half had participated previously as a local investigator, or assisted on a clinical or laboratory study. Factors identified by the members as possibly being disadvantages to participation in a clinical trial, or factors influencing African-American recruitment included: (a) lack of patient awareness of clinical trials (93%); (b) patient mistrust of the medical community (92%); (c) additional administrative tasks in conjunction with a patient enrolled in a study (56%); (d) blind drug assignment (41.6%). African-American physicians perceive inherent disadvantages from participation in clinical trials and have pinpointed factors that may influence patient recruitment. These factors may be addressed by focused physician and community education.

Tonsillar actinomycosis: a clinicopathological study

Actinomycosis has been known to involve virtually every anatomic site in the body. Although actinomycosis has been identified in resected tonsils, its possible role in adeno-tonsillar disease has received little attention. A clinicopathological study of 302 patients who had adeno-tonsillar surgery is presented. Tonsillar actinomycosis was present in 86 (28.5%) patients. The statistical analysis revealed a significant association (P<0.0001) of actinomycosis and tonsillar hypertrophy (56.8%) compared to only 10.3% in the recurrent tonsillitis group. A statistically significant association (P<0.0001) of tonsillar actinomycosis and sickle cell anaemia, beta thalassaemia, bronchial asthma and beta haemolytic streptococcal infections was also seen. This data supports a predisposition of the above conditions to tonsillar actinomycosis and adeno-tonsillar hypertrophy and a possible etiopathologic role of this organism in adeno-tonsillar hypertrophy and disease. Although the clinical association of actinomycosis and tonsillar hypertrophy and beta haemolytic streptococcal infection has been described before the association of actinomycosis with sickle cell anaemia, beta thalassaemia and bronchial asthma is being observed for the first time in literature.

Early morning off-medication dyskinesias, dystonia, and choreic subtypes

BACKGROUND

Abnormal involuntary movements (dyskinesias) are common in patients with Parkinson disease (PD) as a consequence of the disease and dopaminergic replacement therapy. Early morning off-medication choreic dyskinesias have been recently reported after fetal dopaminergic cell transplantations in patients with advanced PD.

OBJECTIVE

To determine the frequency and severity of the early morning off-medication dyskinesias in consecutive patients with advanced PD and an insufficient response to medical management before they undergo neurosurgery.

METHODS

Consecutive patients with advanced idiopathic PD were examined and videotaped before undergoing neurosurgery that included pallidotomy, fetal transplantation, or deep brain stimulation. The examination took place in the morning in the practically defined off state, at least 12 hours after the last dose of dopaminergic drugs. Parkinson disease was characterized using the Unified Parkinson's Disease Rating Scale and the Hoehn and Yahr stage. Dyskinesias were rated with the Abnormal Involuntary Movements Scale and the Rush Dyskinesia Rating Scale. Patients' characteristics and medications were compared using the Wilcoxon rank sum and the Fisher exact tests.

RESULTS

Of 68 consecutive patients (44 [65%] men and 24 [35%] women), 11 (16%) had early morning off-medication dyskinesia, with a 95% upper confidence limit of 24%. Focal dystonia was the most common off-medication dyskinesia, and occurred in 10 patients (15%), with a 95% upper confidence limit of 22%; and off-choreic dyskinesia occurred in 1 patient (1.5%), with a 95% upper confidence limit of 4%. There was no difference in PD medications between the patients with and those without dyskinesias.

CONCLUSIONS

The most common form of off-medication dyskinesia seen in patients with advanced PD is dystonia. Early morning off-medication choreic dyskinesias are rare but do occur in patients with advanced PD before surgical intervention. The presence and type of off-medication dyskinesias should be monitored in clinical and surgical studies in patients with PD as part of the safety and evaluation of clinical benefits.

Probing fibroblast growth factor dimerization and role of heparin-like glycosaminoglycans in modulating dimerization and signaling

For a number of growth factors and cytokines, ligand dimerization is believed to be central to the formation of an active signaling complex. In the case of fibroblast growth factor-2 (FGF2) signaling, heparin/heparan sulfate-like glycosaminoglycans (HLGAGs) are involved through interaction with both FGF2 and its receptors (FGFRs) in assembling a tertiary complex and modulating FGF2 activity. Biochemical data have suggested different modes of HLGAG-induced FGF2 dimerization involving specific protein-protein contacts. In addition, several recent x-ray crystallography studies of FGF.FGFR and FGF.FGFR.HLGAG complexes have revealed other modes of molecular assemblage, with no FGF-FGF contacts. All these different biochemical and structural findings have clarified less and in fact raised more questions as to which mode of FGF2 dimerization, if any, is essential for signaling. In this study, we address the issue of FGF2 dimerization in signaling using a combination of biochemical, biophysical, and site-directed mutagenesis approaches. Our findings presented here provide direct evidence of FGF2 dimerization in mediating FGF2 signaling.

A comparison of stroke risk factors in patients enrolled in stroke prevention trials

The high prevalence of stroke risk factors may explain, in part, the high incidence of stroke in African Americans. To further investigate the role of stroke risk factors, we compared stroke risk factor profiles of patients in the African-American Antiplatelet Stroke Prevention Study (AAASPS) with those in other stroke prevention studies in which the enrollees were predominately white. The baseline characteristics of the AAASPS enrollees obtained from an interim AAASPS database of 1,087 patients from 65 centers in the U.S. between December 1995 and June 1999 was compared to the baseline characteristics of 53,293 predominantly non-African American patients enrolled in 23 other stroke prevention studies (pNAA). Percentages were reported for qualitative characteristics, and means and standard deviations (SDs) for quantitative characteristics. For selected qualitative characteristics, 95% confidence intervals were given for population percentages in each study. The comparison of baseline characteristics showed that hypertension was more prevalent in AAASPS (84% [95% CI 82.2, 86.61) compared to pNAA trial patients (range of 27% to 67%). Diabetes mellitus was more common in AAASPS (39.1%) compared to pNAA trial patients (17.1%). Cardiac disease, however, was less common in AAASPS than in pNAA trials. The frequency of baseline characteristics of AAASPS patients is different from those of pNAA studies. Risk factor profiles are important as they may help to predict stroke subtype and outcome. Furthermore, the differences in baseline characteristics may portend differences in response to treatment and incidence of adverse events.

Genetic variation analysis in parkinson disease patients with and without hallucinations: case-control study

BACKGROUND

Visual hallucinations in Parkinson disease (PD) occur in approximately one third of patients treated long-term with dopaminergic medications. In Alzheimer disease, hallucinations and psychosis have been linked to increased representations of B2/B2 homozyogotes for the dopamine receptor gene DRD1 and 1/1 or 2/2 homozygotes for DRD3. In addition, a previous study of PD patients with and without hallucinations did not show differences in D2 and D3 polymorphisms, although careful case-control matching was not performed. Another study linked the apolipoprotein E4 (APOE4) allele to hallucinations in PD.

OBJECTIVE

To determine whether the frequency of dopamine receptor genetic variants and APOE alleles in patients with PD with and without chronic visual hallucinations resembles the pattern previously documented in patients with Alzheimer disease.

METHODS

We conducted a case-control study of 44 patients with PD and chronic hallucinations and 44 patients with PD who had never hallucinated. Cases and controls were matched for current age and medications. DNA was isolated from blood samples and assayed for DRD1, DRD2, DRD3, DRD4, and APOE polymorphisms. Receptor polymorphisms were genotyped by polymerase chain reaction. Genotypes in hallucinators and nonhallucinators were compared using Mantel-Haenszel tests stratified by pair, and allele frequencies were compared using Wilcoxon signed rank tests within pairs.

RESULTS

Neither D1 receptor genotypes (P =.37) nor allele frequencies (P =.38) differed, and there was no predominance of B2/B2 homozygotes in the hallucinators. For D3, there was a higher frequency of allele 2 (P =.047), but there was no significant difference between frequencies of homozygotes vs heterozygotes (P =.39) as reported in Alzheimer disease. D4 receptor distribution of long and short alleles did not differ between the 2 patient groups, and there were too few C alleles (3 of 86) to compare D2 allele genotypes or frequencies. For APOE, 12 cases and 12 controls carried E4 alleles (P>.99).

CONCLUSIONS

With careful case-control matching, visual hallucinations in PD are not associated with the pattern seen for patients with Alzheimer disease and visual hallucinations. Furthermore, there was no association between hallucinations and APOE. Similar methods using larger sample sizes might be adapted to test whether specific dopaminergic receptor genetic variants are associated with visual hallucinations in PD. Based on our data, the DRD3 allele 2 may merit further study.