Validated image ordering guidelines for odontogenic infections

Overuse of computed tomography (CT) is a prevalent problem across multiple disciplines in healthcare and is common in the workup of odontogenic infections. To address this problem, an imaging pathway was created through collaboration of the oral maxillofacial surgery and emergency medicine departments to reduce unnecessary CT orders. A prospective study was implemented to assess the success of the imaging pathway to guide in the selection of the most appropriate radiological imaging modality when managing an odontogenic infection. Subjects included were adults, presenting through the emergency department for confirmed odontogenic infection. The primary outcome was the rate of unnecessary CT scans performed after the introduction of the pathway. Statistics were performed via the t-test, χ² test, and multiple regression analysis; P < 0.05 was considered significant. Between February 1 and December 15, 2019, 100 patients met the inclusion criteria and were enrolled. The rate of unnecessary CT scans was 25.6%, compared to 56.6% prior to the introduction of the imaging pathway. The pathway did not misclassify any patient to not receive a CT when it was medically necessary. Use of the imaging pathway has the potential to reduce unnecessary CT imaging for odontogenic infections, without negatively affecting patient outcomes.

Association between increased signal intensity at the proximal patellar tendon and patellofemoral geometry in community-based asymptomatic middle-aged adults: a cross-sectional study

BACKGROUND

Histological and epidemiological data suggest that increased signal intensity at the proximal patellar tendon on magnetic resonance imaging is a response to tendon loading. As patellofemoral geometry is a mediator of loading, we examined the association between patellofemoral geometry and the prevalence of increased signal intensity at the patellar tendon in community-based middle-aged adults.

METHODS

Two hundred-one adults aged 25-60 years in a study of obesity and musculoskeletal health had the patellar tendon assessed from magnetic resonance imaging. Increased signal intensity at the proximal patellar tendon was defined as hyper-intense regions of characteristic pattern, size and distribution on both T1- and T2-weighted sequences. Indices of patellofemoral geometry, including Insall-Salvati ratio, patellofemoral congruence angle, sulcus angle, and lateral condyle-patella angle, were measured from magnetic resonance imaging using validated methods. Binary logistic regression was used to examine the association between patellofemoral geometrical indices and the prevalence of increased signal intensity at the patellar tendon.

RESULTS

The prevalence of increased signal intensity at the patellar tendon was 37.3%. A greater Insall-Salvati ratio (odds ratio 0.80, 95% confidence interval 0.66-0.97 per 0.1 change in the ratio, p = 0.02), indicative of a higher-riding patella, and a larger patellofemoral congruence angle (odds ratio 0.91, 95% confidence interval 0.85-0.98 per 5 degree change in the angle, p = 0.01), indicating a more laterally placed patella, were associated with reduced odds of increased signal intensity at the patellar tendon. Sulcus angle and lateral condyle-patella angle were not significantly associated with the odds of increased signal intensity at the patellar tendon.

CONCLUSIONS

In community-based asymptomatic middle-aged adults, increased signal intensity at the patellar tendon was common and associated with Insall-Salvati ratio and patellofemoral congruence angle, suggesting a biomechanical mechanism. Such work is likely to inform tissue engineering and cell regeneration approaches to improving outcomes in those with tendon pathology.

Interferon-Induced Transmembrane Protein 1 Restricts Replication of Viruses That Enter Cells via the Plasma Membrane

The acute antiviral response is mediated by a family of interferon-stimulated genes (ISGs), providing cell-intrinsic immunity. Mutations in genes encoding these proteins are often associated with increased susceptibility to viral infections. One family of ISGs with antiviral function is the interferon-inducible transmembrane proteins (IFITMs), of which IFITM3 has been studied extensively. In contrast, IFITM1 has not been studied in detail. Since IFITM1 can localize to the plasma membrane, we investigated its function with a range of enveloped viruses thought to infect cells by fusion with the plasma membrane. Overexpression of IFITM1 prevented infection by a number of Paramyxoviridae and Pneumoviridae, including respiratory syncytial virus (RSV), mumps virus, and human metapneumovirus (HMPV). IFITM1 also restricted infection with an enveloped DNA virus that can enter via the plasma membrane, herpes simplex virus 1 (HSV-1). To test the importance of plasma membrane localization for IFITM1 function, we identified blocks of amino acids in the conserved intracellular loop (CIL) domain that altered the subcellular localization of the protein and reduced antiviral activity. By screening reported data sets, 12 rare nonsynonymous single nucleotide polymorphisms (SNPs) were identified in human IFITM1, some of which are in the CIL domain. Using an Ifitm1-/- mouse, we show that RSV infection was more severe, thereby extending the range of viruses restricted in vivo by IFITM proteins and suggesting overall that IFITM1 is broadly antiviral and that this antiviral function is associated with cell surface localization.IMPORTANCE Host susceptibility to viral infection is multifactorial, but early control of viruses not previously encountered is predominantly mediated by the interferon-stimulated gene (ISG) family. There are upwards of 300 of these genes, the majority of which do not have a clearly defined function or mechanism of action. The cellular location of these proteins may have an important effect on their function. One ISG located at the plasma membrane is interferon-inducible transmembrane protein 1 (IFITM1). Here we demonstrate that IFITM1 can inhibit infection with a range of viruses that enter via the plasma membrane. Mutant IFITM1 proteins that were unable to localize to the plasma membrane did not restrict viral infection. We also observed for the first time that IFITM1 plays a role in vivo, and Ifitm1-/- mice were more susceptible to viral lung infection. These data contribute to our understanding of how ISGs prevent viral infections.

Incident hand OA is strongly associated with reduced peripheral blood leukocyte telomere length

OBJECTIVE

To evaluate the relationship of telomere length to the prevalence and incidence of hand osteoarthritis in a longitudinal cohort.

DESIGN

We conducted a cross-sectional and longitudinal analysis of data from a subset of participants in the Osteoarthritis Initiative (OAI) recruited between February 2004 and May 2006. 274 individuals were eligible for the study based on availability of both baseline and 48-month hand radiographs and peripheral blood leucocyte telomere length data. Mean telomere length of peripheral blood leukocytes (PBL)s from the DNA samples was determined using a validated quantitative polymerase chain reaction (PCR)-based assay, and hand radiographs were analyzed and graded using the Kellgren-Lawrence scale.

RESULTS

In joint -level analyses, prevalent Interphalangeal Joint Osteoarthritis (IPJOA) was significantly associated with PBL telomere length in the baseline sample in unadjusted analyses (RR = 2.84; 95% CI:0.87-9.29) or in models adjusted for age, sex, and body mass index (aRR = 1.10; 95% CI: 0.96-1.27). The association in crude and adjusted analyses appeared slightly stronger with incident IPJOA, especially in the subset with normal hands at baseline (aRR = 1.62; 95% CI: 1.02-2.57). PBL telomere length was also associated with prevalent HOA at baseline (significant in unadjusted analysis: RR = 1.22; 95% CI 1.06-1.42), but not after adjusting for covariates: aRR = 1.12; 95% CI: 0.96-1.30). The magnitude of association was stronger for incident HOA, especially incident symptomatic HOA (aRR = 1.53; 95% CI: 1.09-2.15).

CONCLUSIONS

In summary, the results of this exploratory analysis are confirmatory of previous work showing a cross-sectional relationship between telomere length and HOA and add to the field by demonstrating an even stronger association with incident IPJOA, both radiographic and symptomatic.

Night Vision after Excimer Laser Photorefractive Keratectomy: Haze and Halos

A series of 85 patients with myopia, up to −6.00D, was treated by photorefractive keratectomy (PRK), using a 5 mm diameter ablation zone. At six months, 38 patients (45%) reported slight disturbances of night vision, nine (11%) of whom had significant problems. Perturbations of night vision after PRK are seen as starbursts and halos around lights. Corneal haze produces the starbursts, which are usually transient. In contrast, halos are myopic blur circles and may be persistent. Using a computer program, halos after PRK were found to be significantly larger than those in emmetropes and myopes corrected with spectacles (p < 0.01). The halos were diminished by using either artificial pupils or negative lens over-correction. In patients with identical bilateral PRK corrections, except for the ablation zone size, the magnitude of the halo was less with 5 mm than 4 mm zones (p < 0.01). Patients treated with 5 mm reported fewer problems attributable to halo than with the 4 mm ablation diameters (p < 0.01). Halos and pupil diameters were measured in nine patients with significant impairment of night vision haze. Those with starbursts had small hyperopic shifts, minimal halos and high haze and light scatter measurements, whilst patients with halos had large hyperopic shifts, little haze and large pupil diameters. Patients with persistent halo problems benefited from either negative lens over-correction or miotics at night.

A phase II trial of lenalidomide plus rituximab in previously untreated follicular non-Hodgkin's lymphoma (NHL): CALGB 50803 (Alliance)

BACKGROUND

This multicenter, phase II trial tested the tolerability and efficacy of lenalidomide plus rituximab in patients with previously untreated follicular lymphoma (FL).

PATIENTS AND METHODS

Patients with grade 1-3a FL, stage 3-4 or bulky stage 2, FL international prognostic index (FLIPI) 0-2, and no prior therapy were eligible to receive rituximab 375 mg/m2 weekly during cycle 1 and day 1 of cycles 4, 6, 8, and 10, plus lenalidomide 20-25 mg on days 1-21 for twelve 28-day cycles. The primary objectives were to evaluate response rates [complete (CR) and overall] and time to progression. Secondary objectives included toxicity, response according to polymorphisms in FcgR2A and FcgR3A, and changes in circulating pro-angiogenic cells.

RESULTS

From October 2010 to September 2011, 66 patients were enrolled. Median age was 53 years, 34 were female, 15 had bulky disease, 21 were FLIPI 0-1, 43 FLIPI 2, and 2 FLIPI 3. One patient withdrew before receiving treatment. Fifty-one patients completed 12 cycles of lenalidomide. Reasons for discontinuation included withdrawal (n = 6), adverse events (n = 6), progression (n = 2). Grade 3-4 hematologic toxicity included neutropenia (21%), lymphopenia (9%), and thrombocytopenia (2%), infection (11%), and rash (8%). Grade 1-2 toxicity included fatigue (78%), diarrhea (37%), rash (32%), and febrile neutropenia in one patient. The overall response rate was 95%; the CR rate was 72% (95% confidence interval, 60% to 83%). With a median follow-up of 5 years, the 2- and 5-year progression-free survival were 86% and 70%, respectively, and the 5-year overall survival was 100%. There was no association between CR rate or PFS and FLIPI, histological grade, bulky disease, FcgR2A/FcgR3A polymorphism, or change in circulating endothelial cell/hematopoietic progenitor cell.

CONCLUSION

Lenalidomide plus rituximab was associated with low rates of grade 3-4 toxicity, yielded a CR rate and PFS similar to chemotherapy-based treatment and may represent a reasonable alternative to immunochemotherapy in previously untreated FL.

CLINICALTRIALS.GOV IDENTIFIER

NCT01145495.

Gold and Hydroxyapatite Nano-Composite Scaffolds for Anterior Cruciate Ligament Reconstruction: In Vitro Characterization

Current anterior cruciate ligament (ACL) graft replacement materials often fail due to the lack of biological integration. While many newly developed extracellular matrix based scaffolds show good biocompatibility they often do not entice cellular remodeling and the rebuilding of a functional ligament. We have proposed the conjugation of gold nanoparticles (AuNP) and hydroxyapatite nanoparticles (nano-HAp) to acellular tissue to enhance cell attachment and proliferation while maintaining an improved degradation resistance and open microstructure. We are the first to investigate the double conjugation of AuNP and nano-HAp onto decellularized tissue to improve the tissue remodeling response. Decellularized porcine diaphragm was crosslinked with two types of nano-HAp and amine-functionalized AuNP with 1-ethyl-3-(3-dimethlaminopropyl) carbodiimide (EDC) crosslinker. Scaffolds were characterized using electron microscopy, differential scanning calorimetry, and fibroblast assays. Results demonstrated that scaffolds with nano-HAp have increased thermal stability at low levels of crosslinking. The open microstructure of the scaffold was not compromised allowing for cell migration while still providing increased degradation resistance. The addition of < 200 nm nano-HAp decreased cell viability compared to scaffolds without nanoparticles, but the addition of AuNP to scaffolds showed enhanced cell viability in the presence of < 200 nm nano-HAp. The addition of < 40 nm nano-HAp showed an increase in cell viability compared to scaffolds crosslinked without nanoparticles. It is concluded that attaching AuNP and < 40nm nano-HAp to extracellular matrices may improve overall properties.

Imaging, procedural and clinical variables associated with tumor yield on bone biopsy in metastatic castration-resistant prostate cancer

BACKGROUND

Understanding the mechanisms driving disease progression is fundamental to identifying new therapeutic targets for the treatment of men with metastatic castration-resistant prostate cancer (mCRPC). Owing to the prevalence of bone metastases in mCRPC, obtaining sufficient tumor tissue for analysis has historically been a challenge. In this exploratory analysis, we evaluated imaging, procedural and clinical variables associated with tumor yield on image-guided bone biopsy in men with mCRPC.

METHODS

Clinical data were collected prospectively from men with mCRPC enrolled on a phase II trial with serial metastasis biopsies performed according to standard clinical protocol. Imaging was retrospectively reviewed. We evaluated the percent positive biopsy cores (PPC), calculated as the number of positive cores divided by the total number of cores collected per biopsy.

RESULTS

Twenty-nine men had 39 bone biopsies. Seventy-seven percent of bone biopsies had at least one positive biopsy core. We determined that lesion size and distance from the skin to the lesion edge correlated with tumor yield on biopsy (median PPC 75% versus 42% for lesions >8.8 cm(3) versus ⩽ 8.8 cm(3), respectively, P=0.05; median PPC 33% versus 71% for distance ⩾ 6.1 versus <6.1 cm, respectively, P = 0.02). There was a trend towards increased tumor yield in patients with increased uptake on radionuclide bone scan, higher calcium levels and shorter duration of osteoclast-targeting therapy, although this was not statistically significant. Ten men had 14 soft tissue biopsies. All soft tissue biopsies had at least one positive biopsy core.

CONCLUSIONS

This exploratory analysis suggests that there are imaging, procedural and clinical variables that have an impact on image-guided bone biopsy yield. In order to maximize harvest of prostate cancer tissue, we have incorporated a prospective analysis of the metrics described here as part of a multi-institutional project aiming to use the molecular characterization of mCRPC tumors to direct individual therapy.

Opening the black box: outcomes of interactions between arbuscular mycorrhizal (AM) and non-host genotypes of Medicago depend on fungal identity, interplay between P uptake pathways and external P supply

We investigated the physiology that underlies the influence of arbuscular mycorrhizal (AM) colonization on outcomes of interactions between plants. We grew Medicago truncatula A17 and its AM-defective mutant dmi1 in intragenotypic (two plants per pot of the same genotype, x2) or intergenotypic (one plant of each genotype, 1 + 1) combinations, inoculated or not with Rhizophagus irregularis (formerly Glomus intraradices) or Gigaspora margarita. We measured plant growth, colonization, contributions of AM and direct P uptake pathways using (32)P, and expression of plant Pi transporter genes at two levels of P supply. A17 (x2) responded positively to inoculation only at low P. The response was enhanced with 1 + 1 even at high P where colonization in A17 was reduced. With R. irregularis P uptake by the AM pathway was unaffected by P supply, whereas with G. margarita, the AM pathway was lower at high P, and direct uptake higher. Gene expression varied and was unrelated to P uptake through the two pathways. There was no evidence of plant control of P uptake via R. irregularis at high P but there was via G. margarita. Importantly, growth responses of plant genotypes grown alone did not predict outcomes of intergenotypic interactions.

Hypoglycaemia-induced changes in regional brain volume and memory function

BACKGROUND

Hypoglycaemic events can be a serious complication of insulin therapy in Type 1 diabetes mellitus. Severe hypoglycaemic exposure can lead to episodic memory impairments, including anterograde amnesia. However, relatively little is known regarding the long-term impact of severe hypoglycaemia on brain structure in Type 1 diabetes mellitus. The goals of the present study were to gain a greater understanding of the long-term effects of severe hypoglycaemia exposure on brain structure and the neural correlates of memory impairments in Type 1 diabetes mellitus.

CASE REPORT

Regional grey and white matter volume and total white matter lesion volume were quantified in an individual with long-standing hypoglycaemia-induced anterograde amnesia and compared with age- and gender-matched healthy controls. Our patient has significant reductions in grey matter volume in the hippocampus, thalamus and pallidum, and significant reductions in white matter volume in the splenium, isthmus of the cingulate and cerebellum. He also has a significantly larger total white matter lesion volume than controls.

CONCLUSION

This case study highlights the potential of hypoglycaemia for permanent deleterious effects on brain structure and memory function. Our results suggest that subcortical grey matter, periventricular white matter and posterior white matter may be most susceptible to injury from hypoglycaemia exposure, and that structural damage to the hippocampus and isthmus of the cingulate may play a central role in hypoglycaemia-induced memory impairments.

The association between body mass index and musculoskeletal foot disorders: a systematic review

The primary aim of this systematic review was to investigate the relationship between body mass index (BMI) and foot disorders. The secondary aim was to investigate whether weight loss is effective for reducing foot pain. Five electronic databases (Ovid MEDLINE, Ovid EMBASE, Ovid AMED, CINAHL and The Cochrane Library) and reference lists from relevant papers were searched in April 2011. Twenty-five papers that reported on the association between BMI and musculoskeletal foot disorders met our inclusion criteria and were reviewed. The evidence indicates: (i) a strong association between increased BMI and non-specific foot pain; and (ii) a strong association between increased BMI and chronic plantar heel pain in a non-athletic population. The evidence is inconclusive regarding the relationship between BMI and the following specific disorders of the foot; hallux valgus, tendonitis, osteoarthritis and flat foot. With respect to our second aim, there were only two prospective cohort studies that reported a reduction in foot symptoms following weight loss surgery. In summary, increased BMI is strongly associated with non-specific foot pain in the general population and chronic plantar heel pain in a non-athletic population. However, there is currently limited evidence to support weight loss to reduce foot pain.

Global isoniazid resistance patterns in rifampin-resistant and rifampin-susceptible tuberculosis

Following the World Health Organization's endorsement of the Xpert® MTB/RIF assay, which rapidly and simultaneously diagnoses tuberculosis (TB) and detects resistance to rifampin (RMP), the question arises to what extent RMP resistance is an adequate marker for multidrug-resistant TB (MDR-TB). A retrospective analysis of data from >81 countries and subnational settings demonstrated that >40% of RMP-resistant isolates from new TB cases did not display resistance to isoniazid (INH) in settings with relatively low MDR-TB prevalence (one third of all countries and subnational settings). Results indicated the need for INH susceptibility testing in addition to RMP susceptibility testing.

Dose-response relationships in tropicamide-induced mydriasis and cycloplegia

1 Mydriatic and cycloplegic effects of tropicamide in the normal and in the guanethidine-treated human eye have been recorded following prolonged exposure of the eye to drug solutions. 2 Marked effects and satisfactory dose-response relationships were observed at drug concentrations within the range 1.25-40 μg/ml, by comparison with concentrations of 5-10 mg/ml usually applied as eye-drops. 3 The findings are discussed in relation to drug concentrations which produce cholinergic antagonism in vitro.

Bioavailability of different preparations of paracetamol

1 Plasma drug concentrations in eight volunteer subjects following oral administration of six preparations of paracetamol have been studied. 2 Significant interindividual differences in plasma paracetamol concentration were found within 1 h but there were no consistent differences between the different drug preparations. The results indicate that all the preparations have equivalent bioavailability. 3 In four subjects, tested with the same preparation on two occasions, the findings suggest that drug absorption may differ from one occasion to another.

Arbuscular mycorrhizal colonization reduces arsenate uptake in barley via downregulation of transporters in the direct epidermal phosphate uptake pathway

*Here, we used barley (Hordeum vulgare) grown in normal and compartmented pots to investigate sensitivity to arsenic (As) in the absence of a positive growth response to arbuscular mycorrhizas (AM). *We tested the hypothesis that upon inoculation with AM fungi downregulation of HvPht1;1 and HvPht1;2 genes (encoding high-affinity inorganic orthophosphate (P(i))-uptake systems in a direct pathway via root epidermis and root hairs) and upregulation of the AM-induced HvPht1;8 (encoding the P(i)-uptake system responsible for transfer of P(i) from the symbiotic interface to cortical cells) play a role in decreased As uptake and hence reduced As sensitivity in AM plants. *Barley did not respond, or responded negatively to colonization by Glomus intraradices in terms of growth. In terms of specific phosphorus (P) uptake (P uptake per g of root) barley was nonresponsive. There was a significant interaction between As treatment and colonization, resulting in a lower As concentration and uptake in AM compared with nonmycorrhizal (NM) plants. *The decreased uptake of As and higher P : As molar ratios in the AM barley can be explained by the operation of the AM pathway as indicated by induction of HvPht1;8 and by down-regulation of HvPht1;1 and HvPht1;2.

Uptake of 5-hydroxy[14C]tryptophan by rat and dog brain slices

Slices of rat brain take up and concentrate 5-hydroxy[(14)C]tryptophan when incubated at 37 degrees C in vitro. Uptake is inhibited by methyldopa and L-phenylalanine in a competitive manner. Only a small proportion of the 5-hydroxy[(14)C]tryptophan taken up is decarboxylated. This observation, and the lack of correlation between the effects of various amino-acid inhibitors on uptake and on decarboxylase, suggest that the two processes are not linked. In the cold some passive diffusion of the amino-acid occurs, as is thought to take place also at 37 degrees C. Experiments with dog brain show that uptake varies from one part of the brain to another, being greatest in the caudate nucleus. The possible implications of the uptake mechanism in the treatment of animals or patients with large doses of amino-acids are discussed.

A randomized trial comparing the efficacy and safety of imiglucerase (Cerezyme) infusions every 4 weeks versus every 2 weeks in the maintenance therapy of adult patients with Gaucher disease type 1

Imiglucerase (Cerezyme) has been the standard of care for treatment of Gaucher disease, a lysosomal storage disorder resulting from deficiency of glucocerebrosidase, since its approval in 1994. Infusions are typically given once every 2 weeks. However, many patients have expressed a desire for less frequent infusions as a matter of convenience. This clinical study assessed the safety and efficacy of intravenous imiglucerase infused once every 4 weeks (Q4) compared to once every 2 weeks (Q2) at the same total monthly dose in adult patients with clinically stable Gaucher disease type 1 (GD1). This was a 24-month, open-label, randomized, Phase 4, dose-frequency study conducted in 25 centers worldwide. Patients receiving imiglucerase were randomized to receive their monthly dose biweekly (n=33) or every 4 weeks (n=62). Changes from baseline in hemoglobin, platelets, liver and spleen volumes, bone crisis, and bone disease comprised a predefined composite endpoint; achievement or maintenance of established Gaucher disease therapeutic goals comprised a secondary endpoint. Sixty-three percent of Q4- and 81% of Q2-treated patients met the composite endpoint at Month 24; 89% of Q4- and 100% of Q2-treated patients met the therapeutic goals-based endpoint. The frequency of related adverse events was comparable between treatment groups. This study suggests that with comprehensive monitoring, a Q4 imiglucerase infusion regimen may be a safe and effective treatment option for the majority of clinically stable adult patients with GD1 but may not be appropriate for all GD1 patients. Continued monitoring in patients treated with Q4 dosing is required to assess long-term effectiveness.

No evidence for competition between arsenate and phosphate for uptake from soil by medic or barley

We investigated the effects of phosphorus (P) supply on the uptake and toxicity of arsenate (As(V)) in two plant species (Medicago truncatula and Hordeum vulgare) grown in soil/sand mixes. Our initial hypothesis was that competition between phosphate (Pi) and As(V) for uptake would be observed, and that this would be the basis for the 'protective' effect of P with respect to As toxicity, as shown in solution culture. Addition of P to the soil/sand mixes did not have major effects on water extractable As, or vice versa. We observed that toxic effects of As(V) on plant growth were ameliorated by increased P in both plant species. However, we found no evidence that increased P supply reduced specific uptake of As(V) on a molar basis, so that competition with Pi could not be the basis for the effect. A more complex mechanism of protection is indicated which might relate to different Pi transport systems being expressed at different P levels.

Arbuscular mycorrhizal inhibition of growth in barley cannot be attributed to extent of colonization, fungal phosphorus uptake or effects on expression of plant phosphate transporter genes

Here, we used phosphorus-32 (32P) labelling in compartmented pots combined with quantitative real-time polymerase chain reaction (PCR) analysis of phosphate(Pi) transporter gene expression to investigate regulation of Pi uptake pathways in barley (Hordeum vulgare), an arbuscular mycorrhizal (AM) plant that does not show strong positive growth responses to colonization.Barley was colonized well by Glomus intraradices and poorly by Glomus geosporum,but both fungi induced significant and similar growth depressions compared with non mycorrhizal controls. The lack of correlation between per cent colonization and extent of growth depression suggests that the latter is not related to carbon drain to the fungus. The contribution of the AM Pi uptake pathway for the two fungi was, in general,related to per cent colonization and expression of the AM-inducible Pi transporter gene, HvPT8, but not to plant responsiveness. Glomus intraradices contributed 48%of total plant P whereas G. geosporum contributed very little.The growth depression in plants where the AM uptake pathway was functional suggests that the contribution of the direct Pi uptake pathway via root hairs and epidermis was decreased. This decrease was not correlated with downregulation of the epidermal-expressed Pi transporter genes, HvPT1 and HvPT2. We hypothesize post-transcriptional or post-translational control of this transport process by AM colonization.

Microdeletion/duplication at 15q13.2q13.3 among individuals with features of autism and other neuropsychiatric disorders

BACKGROUND

Segmental duplications at breakpoints (BP4-BP5) of chromosome 15q13.2q13.3 mediate a recurrent genomic imbalance syndrome associated with mental retardation, epilepsy, and/or electroencephalogram (EEG) abnormalities.

PATIENTS

DNA samples from 1445 unrelated patients submitted consecutively for clinical array comparative genomic hybridisation (CGH) testing at Children's Hospital Boston and DNA samples from 1441 individuals with autism from 751 families in the Autism Genetic Resource Exchange (AGRE) repository.

RESULTS

We report the clinical features of five patients with a BP4-BP5 deletion, three with a BP4-BP5 duplication, and two with an overlapping but smaller duplication identified by whole genome high resolution oligonucleotide array CGH. These BP4-BP5 deletion cases exhibit minor dysmorphic features, significant expressive language deficits, and a spectrum of neuropsychiatric impairments that include autism spectrum disorder, attention deficit hyperactivity disorder, anxiety disorder, and mood disorder. Cognitive impairment varied from moderate mental retardation to normal IQ with learning disability. BP4-BP5 covers approximately 1.5 Mb (chr15:28.719-30.298 Mb) and includes six reference genes and 1 miRNA gene, while the smaller duplications cover approximately 500 kb (chr15:28.902-29.404 Mb) and contain three reference genes and one miRNA gene. The BP4-BP5 deletion and duplication events span CHRNA7, a candidate gene for seizures. However, none of these individuals reported here have epilepsy, although two have an abnormal EEG.

CONCLUSIONS

The phenotype of chromosome 15q13.2q13.3 BP4-BP5 microdeletion/duplication syndrome may include features of autism spectrum disorder, a variety of neuropsychiatric disorders, and cognitive impairment. Recognition of this broader phenotype has implications for clinical diagnostic testing and efforts to understand the underlying aetiology of this syndrome.

Role of diffusion MRI in diagnosis of spinal cord infarction in children

Anterior spinal artery (ASA) infarction is a rare but well-described cause of flaccid paraparesis in adults, presenting with a high thoracic spinothalamic sensory level and preservation of dorsal column function. Careful sensory examination, demonstrating loss of spinothalamic modalities with preservation of dorsal column modalities, supports a clinical diagnosis of ASA infarction. Findings on conventional MRI of the spinal cord are often non-specific, and diffusion-weighted imaging (DWI) is not routinely performed. We describe four children with ASA infarction after minor trauma. DWI was performed in all cases and confirmed the clinical diagnosis.

Bilateral tonic pupils: Holmes Adie syndrome or generalised neuropathy?

AIM

To compare the pupil signs in patients with bilateral pupillotonia caused by Holmes-Adie syndrome or generalised peripheral neuropathy.

METHODS

Infrared video pupillographic techniques were used to measure a number of pupil variables in patients with Holmes-Adie syndrome, generalised neuropathy (various aetiologies) and healthy age-matched control subjects.

RESULTS

Regardless of aetiology, the patients generally had pupil signs typical of pupillotonia (small dark diameters, large light diameters, tonic near responses, attenuated light responses with light-near dissociation, and sector palsy). However, significant differences were found in the prevalence and magnitude of several pupil variables in the two patient groups. In particular, sector palsy and anisocoria exceeding 1 mm (in the light) were seen much more commonly in Holmes-Adie patients than patients with generalised neuropathy. The presence of both these pupil signs can be used to distinguish between these diagnoses with a sensitivity of 58% and a specificity of 90%.

CONCLUSIONS

The tonic pupils of patients with Holmes-Adie syndrome are significantly different to those found in patients with generalised neuropathy; recognition of these differences may allow distinction between these diagnoses.

Structural differences in arbuscular mycorrhizal symbioses: more than 100 years after Gallaud, where next?

This review commemorates and examines the significance of the work of Isobel Gallaud more than 100 years ago that first established the existence of distinct structural classes (Arum-type and Paris-type) within arbuscular mycorrhizal (AM) symbioses. We add new information from recent publications to the previous data last collated 10 years ago to consider whether any patterns have emerged on the basis of different fungal morphology within plant species or families. We discuss: (1) possible control exerted by the fungus over AM morphology; (2) apparent lack of plant phylogenetic relationships between the classes; (3) functions of the interfaces in different structural classes in relation to nutrient transfer in particular; and (4) the occurrence of plants with both of the major classes, and with intermediate AM structures, in different plant habitats. We also give suggestions for future research to help remove uncertainties about the functional and ecological significance of differences in AM morphology. Lastly, we urge retention of the terms Arum- and Paris-type, which are now well recognised by those who study AM symbioses.

Arbuscular mycorrhizal fungi can induce the production of phytochemicals in sweet basil irrespective of phosphorus nutrition

The potential of three arbuscular mycorrhizal fungi (AMF) to enhance the production of antioxidants (rosmarinic and caffeic acids, RA and CA) was investigated in sweet basil (Ocimum basilicum). After adjusting phosphorus (P) nutrition so that P concentrations and yield were matched in AM and non-mycorrhizal (NM) plants we demonstrated that Glomus caledonium increased RA and CA production in the shoots. Glomus mosseae also increased shoot CA concentration in basil under similar conditions. Although higher P amendments to NM plants increased RA and CA concentrations, there was higher production of RA and CA in the shoots of AM plants, which was not solely due to better P nutrition. Therefore, AMF potentially represent an alternative way of promoting growth of this important medicinal herb, as natural ways of growing such crops are currently highly sought after in the herbal industry.

Effects of the arbuscular mycorrhizal fungus Glomus mosseae on growth and metal uptake by four plant species in copper mine tailings

A greenhouse experiment was conducted to evaluate the potential role of arbuscular mycorrhizal fungi (AMF) in encouraging revegetation of copper (Cu) mine tailings. Two native plant species, Coreopsis drummondii and Pteris vittata, together with a turf grass, Lolium perenne and a leguminous plant Trifolium repens associated with and without AMF Glomus mosseae were grown in Cu mine tailings to assess mycorrhizal effects on plant growth, mineral nutrition and metal uptake. Results indicated that symbiotic associations were successfully established between G. mosseae and all plants tested, and mycorrhizal colonization markedly increased plant dry matter yield except for L. perenne. The beneficial impacts of mycorrhizal colonization on plant growth could be largely explained by both improved P nutrition and decreased shoot Cu, As and Cd concentrations. The experiment provided evidence for the potential use of local plant species in combination with AMF for ecological restoration of metalliferous mine tailings.

Isolated lower extremity metastases, 9 years after initial diagnosis of retinoblastoma

We report the development of isolated lower extremity metastases, in a child, 9 years after her initial diagnosis and treatment of bilateral infantile retinoblastomas. The radiographic, scintigraphic, computed tomographic, and magnetic resonance imaging findings are discussed. The dominant metastatic focus was blastic, involving the medial cuneiform. Additional occult lesions were found in the base of the second metatarsal, middle cuneiform, navicular and tibial diaphysis. An open biopsy confirmed the diagnosis. The occurrence of late distant metastases is rare in the USA.

Effect of the arbuscular mycorrhizal fungus Glomus intraradices on expression of cytoskeletal proteins in tomato roots

The expression patterns of the cytoskeletal proteins α-, β-, and γ-tubulin, actin, and myosin were investigated in young tomato roots and older roots at different intensities of mycorrhizal colonization. The relative level of cytoskeletal proteins was estimated by protein blotting and immunostaining. The contribution of plant α-, β-, and γ-tubulin to the total protein pool was higher in uncolonized 2-week-old roots than in 10-week-old roots, whereas the contribution of actin remained constant. The level of plant tubulin expression was clearly higher in mycorrhizal root systems than in uncolonized older root systems. These results indicate that tubulins are more involved in plant cell differentiation than actin. Myosin of approximately 230 kDa was expressed in the roots of 10-week-old wild-type tomato but not in young or mycorrhizal tomatoes. In contrast, a smaller ca. 170 kDa myosin was consistently present in all root samples. Indirect immunofluorescence microscopy showed that plant myosin was located particularly along the periarbuscular membranes surrounding the arbuscule branches. In uncolonized roots, myosin was associated mainly with membranes adjacent to plant cell walls. These data provide novel evidence that myosin expression and localization in root cells responds to mycorrhizal colonization.Key words: actin, myosin, arbuscular mycorrhizal fungi, protein expression, tubulin.

Do iron plaque and genotypes affect arsenate uptake and translocation by rice seedlings (Oryza sativa L.) grown in solution culture?

The effects of Fe concentrations in the pretreatment solution on the induction of plaque and the differences between genotypes on arsenate uptake by and translocation within rice seedlings grown in nutrient solution in the greenhouse were investigated. After iron plaque on rice roots was induced in solutions containing 20, 40, 60, 80, and 100 mg Fe2+ l(-1), seedlings were transplanted into nutrient solution with 0.5 mg As l(-1). The formation of iron plaque was clearly visible as a reddish coating on the root surface after 12 h induction. Fe2+ concentrations in the pretreatment solution and 0.5 mg As l(-1) in the treatment solutions did not significantly affect rice growth. There was a significant correlation between the concentrations of Fe and As in iron plaque on the root surface for the three genotypes. About 75-89% of total As was concentrated in iron plaque (DCB-extracts). There were no significant differences in As concentrations in the roots between the three genotypes; however, As concentrations in shoots differed significantly between them. Arsenic concentrations in shoots were positively correlated with iron concentrations in the shoots. The results suggest that iron plaque may act as a 'buffer' for As in the rhizosphere.

Genotypic and phenotypic heterogeneity in familial microcoria

AIMS

To describe the clinical features and genetic findings in two families presenting with microcoria inherited as an autosomal dominant trait.

METHODS

Both affected and unaffected members of two families displaying familial microcoria were examined. Flash photography or infrared pupillography were used to assess pupils, and a full ophthalmic examination including visual acuity and field testing, refraction, biomicroscopy of anterior and posterior segments, and measurement of intraocular pressure were performed. DNA from the blood of affected and unaffected family members was investigated using standard markers to look for a possible gene defect in the chromosome 13q31-q32 region.

RESULTS

All affected members of both families had pinpoint pupils which responded normally to light and accommodation. None of these subjects exhibited any other ocular abnormality. The iris of affected members showed stromal thinning and apparent absence of the iris dilator muscle in the first family, but was smooth and lacked all trabecular structure in the second family. The microcoria was present at birth in the first family but developed progressively at a later age in the second family. Haplotype analysis suggested the gene defect is not located in the chromosome 13q31-q32 region in the first family but the evidence was not conclusive in the second family.

CONCLUSION

Although both families presented with similar pupil abnormalities inherited as an autosomal dominant trait, they show important phenotypic and genotypic differences suggesting that this is a heterogeneous condition. The possible mechanisms underlying the microcoria are discussed.

Inoculum type does not affect overall resistance of an arbuscular mycorrhiza-defective tomato mutant to colonisation but inoculation does change competitive interactions with wild-type tomato

•  The influence of inoculum type on colonisation of a mycorrhiza-defective tomato mutant, rmc, by the AM fungus Glomus coronatum was studied by comparing inoculum composed predominantly of spores with hyphae growing from mycorrhizal 'nurse plants', including the wild-type tomato progenitor (WT), other Lycopersicon species, and leek. •  Colonisation of rmc was not primarily influenced by inoculum source; minor differences could be attributed to differences in inoculum potential. The mutation is therefore different from other mycorrhiza-defective tomato mutants. •  Growth of rmc was reduced in the presence of nurse plants, because of competition with them, so a second experiment examined the effects of AM colonisation on competition between rmc and the WT tomato. This experiment was a replacement series in which rmc and WT were grown in competition and as single plants, inoculated with G. coronatum or uninoculated. •  The WT did not respond to G. coronatum when grown alone, but responded positively when in competition with rmc. We conclude from the second experiment that mycorrhizal responsiveness is influenced by competition with (in this case) a surrogate nonhost plant rmc in a situation that mimics interspecific competition. It is therefore a community-based parameter. Results are discussed in the context of responses of mycorrhizal vs nonmycorrhizal species and competition in natural plant ecosytems.

Inhaled synthetic surfactant abolishes the early allergen-induced response in asthma

Allergen-induced inhibition of pulmonary surfactant in asthma may promote airway oedema and consequently potentiate the severity of the asthmatic response. A randomised, single-blind, cross-over study of an inhaled synthetic phospholipid dry-powder surfactant (Pumactant) was conducted in atopic, asthmatic subjects with previously documented early and late asthmatic responses (EAR and LAR) to an inhaled allergen. This was conducted to evaluate the role of exogenous surfactant administration on EAR and LAR. A total of seven subjects had complete evaluable data and received the full dose of Pumactant. Asthmatic subjects inhaled two separate doses of 400 mg Pumactant prior to an allergen exposure. The first dose was administered 8 h in advance and the second dose 30 min in advance. The dosage occurred through a purpose-built administration device. This was followed by a standard bronchial-provocation test, and forced expiratory volume in one second (FEV1) was measured at regular intervals over a 10-h period. Pumactant was well tolerated and, surprisingly, abolished the EAR but not the LAR in all seven subjects. The mean area under the curve between 0-2 h (EAR) following bronchial provocation test was 0.08 for the Pumactant treatment group (PT) and 13.29 for the no treatment (NT) group. The maximum drop in FEV1 for EAR was 4.19% and 23.98% in the PT and the NT group, respectively. The demonstration of inhibition of the early asthmatic response by exogenous surfactant, provides the first evidence that pulmonary surfactant dysfunction may also contribute to the very early asthmatic response to allergen. Exogenous surfactant administration could serve as a useful adjunct in controlling the early allergen-induced symptoms in patients with allergic asthma.

Growth and phosphorus nutrition of a Paris-type arbuscular mycorrhizal symbiosis

•  Paris -type arbuscular mycorrhizas (AM) are reportedly the most common morphological type of AM; however, most research has focused on the Arum -type. Asphodelus fistulosus , a common weed in southern Australia, forms Paris -type AM when colonised by Glomus coronatum . It is often found in sites with low nutrient levels, and may therefore be dependent on its AM associations for growth and phosphorus (P) nutrition. •  A. fistulosus was inoculated with G. coronatum and grown in pots containing a soil/sand mixture with P added to give five soil P concentrations. The plants were grown in a glasshouse and harvested 6 and 9 wk after planting, at which times growth, P nutrition and colonisation were measured. •  At low soil P, A. fistulosus showed very marked positive responses to colonisation both in P uptake and growth; both responses decreased with increasing P supply. Colonisation was not greatly reduced by increasing P supply. •  This study appears to be one of the first detailed investigations of P responses in a Paris -type AM, providing insight into what is reportedly the more common but less well studied morphological type of AM.

Assessing state-wide biodiversity in the Florida Gap analysis project

The Florida Gap (Fl-Gap) project provides an assessment of the degree to which native animal species and natural communities are or are not represented in existing conservation lands. Those species and communities not adequately represented in areas being managed for native species constitute 'gaps' in the existing network of conservation lands. The United States Geological Survey Gap Analysis Program is a national effort and so, eventually, all 50 states will have completed it. The objective of Fl-Gap was to provide broad geographic information on the status of terrestrial vertebrates, butterflies, skippers and ants and their respective habitats to address the loss of biological diversity. To model the distributions and potential habitat of all terrestrial species of mammals, breeding birds, reptiles, amphibians, butterflies, skippers and ants in Florida, natural land cover was mapped to the level of dominant or co-dominant plant species. Land cover was classified from Landsat Thematic Mapper (TM) satellite imagery and auxiliary data such as the national wetlands inventory (NWI), soils maps, aerial imagery, existing land use/land cover maps, and on-the-ground surveys. Wildlife distribution models were produced by identifying suitable habitat for each species within that species' range. Mammalian models also assessed a minimum critical area required for sustainability of the species' population. Wildlife species richness was summarized against land stewardship ranked by an area's mandates for conservation protection.

Perceptions of service provision for clients who self-injure in the absence of expressed suicidal intent

This research involved interviewing three people who had experienced self-injury. They were accessed from the voluntary sector as I felt that if I had accessed them from the National Health Service their views might not be honest, due to their possible perceptions of threats to their care. It was not intended that the views of these people would be representative, my aim was that their views, as well as areas highlighted in the literature, would inform me of areas pertinent to the topic, when seeking staff views. The views of staff, of which there were 15 self-selecting clinicians, formed the main focus of the study. The aims of the research were designed to highlight potentially contrasting perceptions of self-injury as a means of illuminating a current clinical problem. The results showed that staff on the whole agreed with the perceptions of people who have experienced self-injury; that they are often viewed negatively, though this is changing. It was recognized that care was dependent on where the person entered the service. Staff recognized that the service is under pressure and provision may not be available in the voluntary sector for these clients.

Tubular aggregate myopathy with abnormal pupils and skeletal deformities

A patient is described with a novel syndrome characterised by progressive muscular weakness, contractures, pupillary muscle dysfunction, and skeletal deformity. The main myopathological feature was an abundance of tubular aggregates in both type I and type II muscle fibres. Myopathies in which tubular aggregates are the defining feature are rare and either present with progressive muscle weakness or exercise induced myalgia. Tubular aggregate myopathy with symptomatic smooth muscle dysfunction and skeletal deformities has not been described before.

R-phycoerythrin as a time-temperature integrator to verify the thermal processing adequacy of beef patties

The objective of this study was to relate R-phycoerythrin (PE) fluorescence decay to the inactivation of Salmonella in beef patties cooked using adequate and inadequate thermal processes as defined by the U.S. Department of Agriculture (USDA) safe harbor requirements and lethality standards. Ground beef containing 4.8 or 19.1% fat was inoculated with an eight-strain cocktail of Salmonella and formed into 113-g patties. Capillary tubes containing PE in borate buffer at pH 9.0 were attached to a thermocouple and inserted horizontally into the patties. Patties (n = 43) were cooked on a grill maintained at 177 degrees C for 6 to 13 min and reached internal temperatures ranging from 57 to 77 degrees C. Patties were analyzed for Salmonella survivors and for fluorescence decay of PE. The thermal lethality of each process was calculated at a reference temperature of 65 degrees C. Twenty-four of the 43 high-fat patties met the USDA safe harbor regulations, with thermal lethalities of >66 s, whereas only 20 of these patties met the proposed 5-log10 lethality standard. Three of the 20 low-fat patties that met USDA regulations did not meet the proposed lethality standard. A normalized PE fluorescence value of about 0.3 (confidence interval = 99%) indicated that patties had been processed sufficiently to reduce Salmonella by 5 log10 cycles. PE has the potential for use as a marker to verify processing adequacy in food-processing plants and in other settings in which the use of the target pathogen is inappropriate.

Cross walls in arbuscular trunk hyphae form after loss of metabolic activity

•  A time-course of Allium porrum colonized by Glomus coronatum examined the formation of cross walls in arbuscular trunk hyphae in relation to the development and senescence of arbuscules. •  Mycorrhizal structures visualized using nitroblue tetrazolium as a vital stain indicated metabolically active arbuscules and intercellular hyphae with counterstaining by acid fuchsin. The intrahyphal location and intact nature of cross walls was examined using confocal microscopy. Their presence was correlated with the metabolic status of the mycorrhizal unit (i.e. arbuscule branches, arbuscular trunk hypha and intercellular hypha) using an interdependence magnified intersects technique (IMIT). •  Loss of metabolic activity was observed first from arbuscule branches, then from trunk hypha and lastly from intercellular hyphae. Cross walls were seen in trunk hyphae of many inactive arbuscules. The incidence of cross walls increased with time and was associated with loss of activity. •  Observations suggest cross walls appeared after loss of metabolic activity in arbuscule branches in several plant-fungal combinations. The implications of cross-wall formation for mechanisms of transfer of nutrients between fungus and plant are discussed.

Plant growth and cation composition of two cultivars of spring wheat (Triticum aestivum L.) differing in P uptake efficiency

Phosphorus (P)-zinc (Zn) interactions were investigated in two wheat cultivars (Brookton versus Krichauff) differing in P uptake efficiency. The experiment was done in a growth chamber. Rock phosphate (RP) or CaHPO4 (CaP) were used as P sources, and ammonium nitrate (AN) or nitrate only (NO) were used as nitrogen sources. Two Zn levels were used, 0.22 mg x kg(-1) (LZ) and 2.2 mg ZnSO4.7H2O x kg(-1) (HZ), respectively. P availability significantly affected plant biomass production, but Zn supply had little effect. Plants fed ammonium nitrate had significantly lower concentrations of cations than those fed nitrate only. Cultivar Brookton (with higher P uptake efficiency) consistently had lower concentrations of cations than cv. Krichauff (with low P uptake efficiency) under limited P supply. The differences in concentrations of cations increased with the decrease in P availability, but were not affected by Zn supply. The ratio of potassium in roots to shoots of cultivar Brookton was always higher than in cultivar Krichauff. Based on these findings, it is postulated that the lower concentrations of cations in cultivar Brookton are related to root exudation of organic anions, and a conceptual model is established to describe the regulation of root exudation of organic anions and concentrations of cations.

Plant growth and cation composition of two cultivars of spring wheat (Triticum aestivum L.) differing in P uptake efficiency

Phosphorus (P)-zinc (Zn) interactions were investigated in two wheat cultivars (Brookton versus Krichauff) differing in P uptake efficiency. The experiment was done in a growth chamber. Rock phosphate (RP) or CaHPO4 (CaP) were used as P sources, and ammonium nitrate (AN) or nitrate only (NO) were used as nitrogen sources. Two Zn levels were used, 0.22 mg x kg(-1) (LZ) and 2.2 mg ZnSO4.7H2O x kg(-1) (HZ), respectively. P availability significantly affected plant biomass production, but Zn supply had little effect. Plants fed ammonium nitrate had significantly lower concentrations of cations than those fed nitrate only. Cultivar Brookton (with higher P uptake efficiency) consistently had lower concentrations of cations than cv. Krichauff (with low P uptake efficiency) under limited P supply. The differences in concentrations of cations increased with the decrease in P availability, but were not affected by Zn supply. The ratio of potassium in roots to shoots of cultivar Brookton was always higher than in cultivar Krichauff. Based on these findings, it is postulated that the lower concentrations of cations in cultivar Brookton are related to root exudation of organic anions, and a conceptual model is established to describe the regulation of root exudation of organic anions and concentrations of cations.

Plant growth and cation composition of two cultivars of spring wheat (Triticum aestivum L.) differing in P uptake efficiency

Phosphorus (P)-zinc (Zn) interactions were investigated in two wheat cultivars (Brookton versus Krichauff) differing in P uptake efficiency. The experiment was done in a growth chamber. Rock phosphate (RP) or CaHPO4 (CaP) were used as P sources, and ammonium nitrate (AN) or nitrate only (NO) were used as nitrogen sources. Two Zn levels were used, 0.22 mg x kg(-1) (LZ) and 2.2 mg ZnSO4.7H2O x kg(-1) (HZ), respectively. P availability significantly affected plant biomass production, but Zn supply had little effect. Plants fed ammonium nitrate had significantly lower concentrations of cations than those fed nitrate only. Cultivar Brookton (with higher P uptake efficiency) consistently had lower concentrations of cations than cv. Krichauff (with low P uptake efficiency) under limited P supply. The differences in concentrations of cations increased with the decrease in P availability, but were not affected by Zn supply. The ratio of potassium in roots to shoots of cultivar Brookton was always higher than in cultivar Krichauff. Based on these findings, it is postulated that the lower concentrations of cations in cultivar Brookton are related to root exudation of organic anions, and a conceptual model is established to describe the regulation of root exudation of organic anions and concentrations of cations.

End result study of Stone bunionectomies

The Stone bunionectomy is an oblique resection of the metatarsal head designed to preserve the weight-bearing margin of the metatarsal shaft. In 132 patients treated by the Stone operation, only 77 per cent were satisfied with the overall results and 19 per cent had persistent pain. In addition, only 69 per cent were considered by the authors to have had an excellent result. These results do not compare favorably with those reported for the Keller procedure. Consequently, the Stone bunionectomy is not recommended.

The pupil in dominant optic atrophy

PURPOSE

To compare visual and pupil afferent function in dominant optic atrophy (DOA).

METHODS

Patients with DOA who belonged to families showing evidence of linkage to the locus on chromosome 3q28-qter were recruited from the Moorfields Genetic Register. Patients and healthy control subjects underwent visual and pupil perimetry using a modified automated perimeter (Octopus 1-2-3; Interzeag, Schlieren, Switzerland). Five stimulus locations were tested: fixation, and at 17 degrees eccentricity along the 45 degrees and 135 degrees meridians in all four quadrants. The visual deficit (difference in decibels between the patient's luminance threshold and that in age-matched healthy control subjects) was compared directly with the pupil deficit (difference in decibels between the stimulus intensity giving the patient's pupil response and that giving an equivalent pupil response in healthy control subjects) at each test location.

RESULTS

Visual deficits and pupil afferent deficits were found at all five locations. The visual deficits were significantly greater than the pupil deficits at the four peripheral locations (median difference = 6.3 dB, P: < 0.001). At fixation, the difference was not significant (median difference = 2.3 dB, P: = 0.407).

CONCLUSIONS

Pupil function appears less affected than visual function at four of five locations tested. This result provides evidence that the retinotectal fibers serving the pupil light reflex are less susceptible to damage from the OPA1 genetic defect than the retinogeniculate fibers serving vision.