Genomic diversification of giant enteric symbionts reflects host dietary lifestyles

Herbivorous surgeonfishes are an ecologically successful group of reef fish that rely on marine algae as their principal food source. Here, we elucidated the significance of giant enteric symbionts colonizing these fishes regarding their roles in the digestive processes of hosts feeding predominantly on polysiphonous red algae and brown Turbinaria algae, which contain different polysaccharide constituents. Using metagenomics, single-cell genomics, and metatranscriptomic analyses, we provide evidence of metabolic diversification of enteric microbiota involved in the degradation of algal biomass in these fishes. The enteric microbiota is also phylogenetically and functionally simple relative to the complex lignocellulose-degrading microbiota of terrestrial herbivores. Over 90% of the enzymes for deconstructing algal polysaccharides emanate from members of a single bacterial lineage, "Candidatus Epulopiscium" and related giant bacteria. These symbionts lack cellulases but encode a distinctive and lineage-specific array of mostly intracellular carbohydrases concurrent with the unique and tractable dietary resources of their hosts. Importantly, enzymes initiating the breakdown of the abundant and complex algal polysaccharides also originate from these symbionts. These are also highly transcribed and peak according to the diel lifestyle of their host, further supporting their importance and host-symbiont cospeciation. Because of their distinctive genomic blueprint, we propose the classification of these giant bacteria into three candidate genera. Collectively, our findings show that the acquisition of metabolically distinct "Epulopiscium" symbionts in hosts feeding on compositionally varied algal diets is a key niche-partitioning driver in the nutritional ecology of herbivorous surgeonfishes.

Self-reported knowledge, attitudes and behaviour towards evidence-based practice of occupational therapy students in Ireland

It is widely accepted that the occupational therapy profession needs to incorporate research findings into clinical practice so as to improve client outcomes. The purpose of this study was to investigate the knowledge and attitudes toward evidence-based practice (EBP) of occupational therapy students in the Republic of Ireland. A validated questionnaire was used to survey the population of final-year students from the four universities in Ireland in 2008. There was a response rate of 77% (n = 86) to the Knowledge, Attitude and Behaviour Questionnaire. All students reported that they had a clear understanding of EBP and were willing to practice EBP in the future. The majority (85%, n = 73) reported accessing evidence weekly or more often. Lack of time and fieldwork educators not practising EBP were important barriers for 31% (n = 27) and 27% (n = 23), respectively. Over half (55%, n = 47) reported difficulty in finding evidence. The internet (28%, n = 24) and textbooks (27%, n = 23) were the most popular sources of evidence. Limitations include the self-report, cross-sectional design. Future research could include longitudinal studies to understand the transfer of learning into clinical practice.

Medium- and long-term outcome of laparoscopic redo fundoplication

BACKGROUND

For a small subset of patients, laparoscopic fundoplication fails, typically resulting in recurrent reflux or severe dysphagia. Although redo fundoplications can be performed laparoscopically, few studies have examined their long-term efficacy.

METHODS

Using a prospectively maintained database, the authors identified and contacted 41 patients who had undergone redo laparoscopic fundoplications at the University of Washington between 1996 and 2001. The median follow-up period was 50 months (range, 20-95 months). Current symptoms were compared with those acquired and entered into the authors' database preoperatively. Patients also were asked to return for esophageal manometry and pH testing.

RESULTS

All redo fundoplications were performed laparoscopically. There were no conversions. The most common indication for redo fundoplication was recurrent reflux. The most common anatomic abnormality was a herniated wrap. Heartburn improved in 61%, regurgitation in 69%, and dysphagia in 74% of the patients. Complete resolution of these symptoms was achieved, respectively, in 45%, 41% and 38% of these same patients. Overall, 68% of the patients rated the success of the procedure as either "excellent" or "good," and 78% said they were happy they chose to have it. For those who underwent reoperation for gastroesophageal reflux disease, distal esophageal acid exposure according to 24-h pH monitoring decreased after redo fundoplication from 15.7% +/- 18.1% to 3.4% +/- 3.6% (p = 0.041).

CONCLUSION

Although not as successful as primary fundoplication, a majority of patients can expect durable improvement in their symptoms with a laparoscopic redo fundoplication.

Long-term outcomes of laparoscopic antireflux surgery for gastroesophageal reflux disease (GERD)-related airway disorder

A strong link exists between gastroesophageal reflux disease (GERD) and airway diseases. Surgical therapy has been recommended as it is more effective than medical therapy in the short-term, but there is little data on the effectiveness of surgery long-term. We analyzed the long-term response of GERD-related airway disease after laparoscopic anti-reflux surgery (LARS).

METHODS

In 2004, we contacted 128 patients with airway symptoms and GERD who underwent laparoscopic antireflux surgery (LARS) between 12/1993 and 12/ 2002. At median follow-up of 53 months (19-110 mo) we studied the effects on symptoms, esophageal acid exposure, and medication use and we analyzed the data to determine predictors of successful resolution of airway symptoms.

RESULTS

Cough, hoarseness, wheezing, sore throat, and dyspnea improved in 65-75% of patients. Heartburn improved in 91% (105/116) of patients and regurgitation in 92% (90/98). The response rate for airway symptoms was the same in patients with and without heartburn. Almost every patient took proton pump inhibitors (PPIs) preoperatively (99%, 127/128) and 61% (n = 78) were taking double or triple dose. Postoperatively, 33% (n = 45) of patients were using daily antiacid therapy but no one was on double dose. The only factor that predicted a successful surgical outcome was the presence of abnormal reflux in the pharynx as determined by 24-hour pharyngeal pH monitoring. One hundred eleven (87%) patients rated their results as excellent (n = 78, 57%) or good (n = 33, 24%).

CONCLUSION

LARS provides an effective and durable barrier to reflux, and in so doing improves GERD-related airway symptoms in approximately 70% of patients and improves typical GERD symptoms in approximately 90% of patients. Pharyngeal pH monitoring identifies those patients more likely to benefit from LARS, but better diagnostic tools are needed to improve the response of airway symptoms to that of typical esophageal symptoms.

Warfarin prevalence, indications for use and haemorrhagic events

Warfarin, the standard oral anticoagulant drug used in Ireland, is a widely prescribed medication, particularly in the elderly. A HSE Mid-Western Area wide audit was undertaken over a 12-month period to examine the prevalence and indications for warfarin use and haemorrhagic complications associated with the drug. Every patient receiving warfarin therapy over a 13-week period was included (2564). The age standardised rate varied from 0.09% of 35-39 year olds to 6.1% of 80-84 year olds. Atrial fibrillation was the most common indication (54%) in patients attending the Mid-Western Regional Hospital anticoagulation clinic. The annual cumulative incidence of adverse haemorrhagic events in patients with a recorded INR > or = 5.0 episode was 16.6%. The incidence of major and minor haemorrhagic events per INR > or = 5.0 episode was 1.3% and 15.3% respectively. The most common sites of haemorrhage were genitourinary (39%) and gastrointestinal (27%). No fatal or intracranial haemorrhage relating to episodes of over-anticoagulation were reported during the audit period. The most frequent reason for over-anticoagulation was drug interaction (43%). In 74% of patients, the elevated INR was reversed by omitting or reducing warfarin dose. In 17% of cases, vitamin K was administered. Only 3% of incidents were treated with fresh frozen plasma or prothrombin complex concentrates.

Autologous stem cell transplantation in myeloma: the St James's Hospital experience, 1997-2003

BACKGROUND

High-dose treatment with autologous stem cell transplantation (ASCT) has become the standard of care for patients with myeloma below the age of 65 years.

AIMS

We report an audit of 60 patients (median age: 52.5 years) who underwent ASCT in the National Bone Marrow Transplant centre in St James's Hospital in Dublin between 1997 and 2003 inclusive.

METHODS

Clinical and laboratory data were retrieved from patient medical records and hospital information management systems.

RESULTS

Thirty-six patients had IgG, 11 IgA, 1 IgD, 9 light chain and 3 non-secretory MM. Fifty-seven (95%) patients received anthracycline-corticosteroid combination chemotherapy prior to autografting. There was no transplant-related mortality (TRM). Complete (CR) and Partial Responses (PR) were seen in 16 (29.6%) and 29 (53.7%) of those evaluable (n = 54 (90%)). The actuarial Progression-Free (PFS) and Overall Survival (OS) rates at five years are 13% and 55% respectively.

CONCLUSION

Centre outcome is comparable to published international series and supports the use of ASCT in the treatment of this malignancy.

Writing to patients: 'putting the patient in the picture'

We have explored consultant, general practitioner and patient attitudes toward the proposal that following an outpatient consultation, consultants should consider communicating directly with patients in the form of a summary letter, with a copy to the referring general practitioner or other professionals as appropriate. We conducted in-depth interviews with a purposive sample of 20 consultants, 16 patients and 12 general practitioners. The consultants and general practitioners were both involved in the care of participating patients. Patients highlighted the likely value of summary letters including, increased knowledge, improvement recall of the clinical encounter, and reassurance. Clinicians were concerned that patients would not understand letters from consultants. Additional concerns included the impact of letter on consultant-general practitioner relationship and medico-legal issues. These findings reflect fundamental differences in expectations about the nature and quality of communications between doctors and their patients.

Cerebral venous sinus thrombosis precipitated by Graves' disease and Factor V Leiden mutation

We report a case of simultaneous presentation of cerebral venous sinus thrombosis and thyrotoxicosis in a 28 year-old female subsequently found to have the Factor V Leiden mutation. She made an excellent neurological recovery with anticoagulation. The mode of presentation of the case was surprising, as she had no thrombotic episodes in two previous pregnancies. This suggests that thyrotoxicosis may give rise to a hypercoagulable state.

Pseudoexfoliation and sensorineural hearing loss

AIMS

There is increasing evidence that pseudoexfoliation (PXF) not only affects ocular anterior segment structures, but may also be a systemic disease. This study was undertaken to assess the relationship between PXF and sensorineural hearing loss.

METHODS

Patients with PXF were identified from hospital records and underwent complete ocular examination. The sum of pure-tone hearing thresholds measured at 1, 2 and 3 kHz (HTL1,2,3) in each ear was compared with the ISO 7029 standard sex-matched, median age-associated hearing loss summed over the same frequencies (AAHL1,2,3). The proportion of ears with thresholds higher than the ISO 7029 median AAHL1,2,3 on the same side as eyes without PXF was compared with the proportion of ears ipsilateral to eyes with PXF but without glaucoma and similarly the proportion of ears on the same side as eyes with PXF and glaucoma.

RESULTS

In total, 69 patients were studied, of whom 39 were male (56.5%). The mean age of the male patients was 75.8 years, while that of the female group was 75.1 years. All patients had PXF affecting at least one eye. Overall 101 ears (73.7%) had a higher HTL1,2,3 than the ISO 7029 median AAHL1,2,3 which included 56 ears of 78 in the male group (71.8%) and 45 ears of 59 in the female group (76.3%). There was no significant difference between the proportion of ears with HTL1,2,3 higher than the ISO 7029 median AAHL1,2,3 on the same side as eyes without PXF, with PXF but not glaucoma and with PXF and glaucoma, in either the male or female groups.

CONCLUSIONS

A large proportion of patients with PXF have sensorineural hearing loss in comparison to age-matched controls, regardless of whether or not there is associated glaucoma. This finding supports the theory that PXF may be a systemic condition.

Classification of the spectrum of Coats' disease as subtypes of idiopathic retinal telangiectasis with exudation

PURPOSE

An increasing variety of eponymous terms have been used to describe atypical cases of Coats' disease. A group of typical cases of Coats' disease and other cases of differing severity were classified as one of four subtypes of idiopathic retinal telangiectasis with exudation and compared with regard to clinical outcome.

METHODS

In a retrospective clinical review patients with typical and atypical Coats' disease were classified as severe, focal, juxtafoveal or associated (with another disease) forms of idiopathic retinal telangiectasis with exudation.

RESULTS

53 eyes in 50 patients were examined of which 62% (n=31) were male. 12 eyes were classified as severe (group 1), 22 focal (group 2), 12 juxtafoveal (group 3) and 7 associated (group 4). The mean age at diagnosis was lowest in group 1 eyes (6.8 years). The best visual acuity at presentation was 6/60 in group 1 whereas high proportions of eyes in the other groups had initial visual acuities of 6/24 or better. In group 1 only one eye was treated, the majority of eyes were blind or had been enucleated whereas 34 (79%) of eyes in the other groups were suitable for treatment and 29 eyes (67%) retained pre-treatment visual acuity or better at last follow-up.

CONCLUSIONS

Idiopathic retinal telangiectasis with exudation is a spectrum of disease, which is synonymous with Coats' disease. In this retrospective study eyes with severe idiopathic retinal telangiectasis with exudation corresponding to typical Coats' disease, have poorer vision at presentation, are less suitable for treatment and have worse outcomes than eyes with other subtypes. The spectrum of disease severity seen in idiopathic retinal telangiectasis with exudation may be due to second somatic mutations in genes with an existing germline mutation (the two hit theory) and a mosaic phenotype.

Two cases of hereditary optic atrophy associated with an enzymatic defect of the respiratory chain

Hereditary optic atrophy is a significant cause of optic atrophy in children. We report two male siblings who suffered profound irreversible loss of vision over a 2-month period. Neither patient had any prior ophthalmic problems. Both siblings had a metabolic disorder characterized by transient episodes of ataxia and paresis, whereas in one brother a slight increase of lactate in blood and cerebrospinal fluid was detected during an acute episode. Respiratory chain defect in complex I was confirmed in one patient.

Eyelid hypertrichosis associated with latanoprost is reversible

A 56-year-old woman with primary open-angle glaucoma in an only eye presented with hypertrichosis after using Latanoprost to lower IOP. After trabeculectomy with adjunctive Mitomycin C, IOP was well controlled and antiglaucoma medications could be discontinued. At eight-month follow-up the abnormal eyelashes had disappeared.

Pupillary autonomic denervation with increasing duration of diabetes mellitus

BACKGROUND/AIMS

The autonomic pupillary changes in type I and II diabetic patients without clinical evidence of diabetic autonomic neuropathy (DAN) were compared with age matched controls. The relation between pupillary and cardiovascular autonomic function was assessed in the diabetic patients.

METHODS

A case-control study was performed with diabetics grouped according to type and duration of diabetes. Static infrared pupillography was used to compare mean dark adapted pupil size and mean percentage changes in pupil size with pilocarpine 0.1% and cocaine 4% in the diabetic and control groups. All diabetic patients underwent cardiovascular autonomic function assessment using the Valsalva ratio, the 30:15 ratio, and testing for orthostatic hypotension.

RESULTS

In total, 72 type I and 69 type II diabetic patients were compared with 120 controls. Mean dark adapted pupil size was significantly smaller in diabetic groups than controls. Except for type I diabetics with disease for less than 5 years, all patient groups had significantly greater mean percentage constriction in pupil size in response to dilute pilocarpine than controls. There was no significant difference between the mean percentage dilatation in response to cocaine 4% in diabetics and controls. A high proportion of patients had normal cardiovascular autonomic function particularly when this was assessed with the Valsalva ratio.

CONCLUSIONS

Denervation hypersensitivity to dilute pilocarpine is a result of damage to the pupillary parasympathetic supply of diabetic patients. This occurs before the pupillary sympathetic pathway is affected, it can be detected early in the disease, and it may be a possible explanation for the small pupil size seen in diabetic patients. Pupillary autonomic dysfunction occurs before cardiovascular autonomic changes and detection of pupil denervation hypersensitivity to dilute pilocarpine is an inexpensive way to detect early DAN.

Autosomal dominant peripheral cystic retinal patches and non-cystic retinal tufts associated with peripapillary crescents, retinal breaks and uveitis

PURPOSE

To characterise an Irish kindred with apparent autosomal dominant peripheral retinal lesions and peripapillary crescents associated with retinal breaks and uveitis and assess whether these findings were associated with altered homocysteine metabolism.

METHODS

Family members were followed prospectively and regularly examined. Molecular genetic analysis was performed on family members to detect cystathionine beta-synthase (CBS) 307G-S and 5,10-methylenetetrahydrofolate (MTHFR) 677C-T mutations.

RESULTS

Over 11 years, 25 family members in four generations were examined, none of whom had significant refractive errors. Fifteen affected individuals had peripheral cystic retinal patches and in some cases non-cystic retinal tufts, associated with peripapillary pigmentation. Mean age at first examination of affected and non-affected individuals was the same. During follow-up the fundal findings remained unchanged in the affected group and no clinical characteristics developed in the unaffected individuals. Two affected siblings had associated uveitis and rhegmatogenous retinal detachment, which were successfully treated, while a third affected individual had a pigmented retinal break not requiring treatment. Heterozygosity for the CBS 307G-S mutation did not segregate with affected individuals while the MTHFR 677C-T mutation was not detected.

CONCLUSIONS

This family has previously undescribed fundal findings inherited in an apparent autosomal dominant pattern associated with retinal breaks and uveitis. There is no associated inherited alteration of homocysteine metabolism.

The effects of ropivacaine hydrochloride on platelet function: an assessment using the platelet function analyser (PFA-100)

Amide local anaesthetics impair blood clotting in a concentration-dependent manner by inhibition of platelet function and enhanced fibrinolysis. We hypothesised that the presence of ropivacaine in the epidural space could decrease the efficacy of an epidural blood patch, as this technique requires that the injected blood can clot in order to be effective. Ropivacaine is an aminoamide local anaesthetic used increasingly for epidural analgesia during labour. The concentration of local anaesthetic in blood achieved in the epidural space during the performance of an epidural blood patch is likely to be the greatest which occurs (intentionally) in any clinical setting. This study was undertaken to investigate whether concentrations of ropivacaine in blood, which could occur: (i) clinically in the epidural space and (ii) in plasma during an epidural infusion of ropivacaine, alter platelet function. A platelet function analyser (Dade PFA-100, Miami) was employed to assess the effects of ropivacaine-treated blood on platelet function. The greater concentrations of ropivacaine studied (3.75 and 1.88 mg x ml(-1)), which correspond to those which could occur in the epidural space, produced significant inhibition of platelet aggregation. We conclude that the presence of ropivacaine in the epidural space may decrease the efficacy of an early or prophylactic epidural blood patch.

Thermolabile MTHFR genotype and retinal vascular occlusive disease

BACKGROUND

Raised levels of total plasma homocysteine (tHcy) are associated with an increased risk of retinal vascular occlusive disease. A thermolabile form of a pivotal enzyme in homocysteine metabolism, methylenetetrahydrofolate reductase (MTHFR), has been associated with vascular occlusive disease and raised tHcy levels. The relation between thermolabile MTHFR genotype, tHcy, and retinal vascular occlusive disease has not been determined.

METHODS

A retrospective case-control study involving hospital based controls and cases with retinal vascular occlusions in whom tHcy levels had been determined was undertaken. Genotyping for the MTHFR 677 C-T mutation that specifies the thermolabile form of the enzyme was performed by established methods in all subjects. The relation between homozygosity for thermolabile MTHFR genotype (TT), raised tHcy levels, and risk of retinal vascular occlusive disease was examined.

RESULTS

87 cases of retinal vascular occlusive disease (mean age 68.7 years) comprising 26 cases of retinal artery occlusion and 61 of retinal vein occlusion were compared with 87 controls (mean age 70.2 years). The TT genotype did not confer a significantly increased risk of retinal vascular occlusive disease. The mean tHcy level was significantly higher in the cases than in the controls (p<0.0001). Overall, and in both the cases and controls, the frequency of the TT genotype was higher in those with normal tHcy levels than in those with increased levels of tHcy. However, the TT genotype did not significantly alter the risk of increased tHcy levels in these patients.

CONCLUSIONS

The TT genotype is not associated with an increased risk of retinal vascular occlusive disease or increased tHcy levels in this group of elderly patients. In older patients, nutritional rather than genetic factors may be more important in increasing tHcy levels, a known risk factor for retinal vascular occlusive disease.

Detection and prevalence of early diabetic retinopathy in juvenile diabetics with diabetes for 10 years or more

PURPOSE

To compare clinical examination using green light with clinical examination using white light in detecting early diabetic retinopathy (DR) in juvenile diabetic patients with disease for 10 or more years.

METHODS

All patients were examined clinically using both green light and white light to determine the presence of DR. Each patient underwent seven-field fundus photography, which was used as the defined standard against which the clinical examinations were compared and also to determine the prevalence of DR. Data on age at diagnosis, duration of diabetes mellitus, recent HbA1c levels, treatment for systemic hypertension and microalbuminuria were obtained from medical records.

RESULTS

When compared with the defined standard, fundal examination with green light was more sensitive, more specific and had higher predictive values than examination with white light in the detection of early DR. The overall prevalence of DR was 44%, which in all cases was classified as minimal to mild background DR. Patients with DR had significantly higher mean HbA1c levels than those without (p = 0.016). There was no significant association between the prevalence of DR and age at time of examination or diagnosis, duration of diabetes, patient gender, microalbuminuria levels or treatment for systemic hypertension.

CONCLUSION

Fundal examination with green light is better than white light in detecting early DR in juvenile diabetics with duration of disease of 10 years or more. Furthermore the presence of DR is associated with poorer diabetic control. Due to coincident lifestyle changes and the probability of long duration of disease, accurate detection of early DR in juvenile diabetics with diabetes for over 10 years is important.

Raised plasma homocysteine as a risk factor for retinal vascular occlusive disease

BACKGROUND/AIMS

A moderately elevated plasma concentration of the sulphur amino acid homocysteine is an independent risk factor for atherosclerotic vascular disease. Many of the risk factors associated with coronary, cerebral, and peripheral atherosclerotic vascular disease are common to retinal vascular occlusive disease but it is unclear whether elevated plasma concentrations of homocysteine are also associated with such disease. This study assessed the relation between retinal vascular occlusive disease and elevated levels of plasma total homocysteine (tHcy).

METHODS

A retrospective case-control study involving hospital based controls and cases with retinal artery, central retinal vein (including hemiretinal vein), and branch retinal vein occlusions was performed. The relation between elevated tHcy, defined as a level greater than or equal to 12 micromol/l and risk of retinal vascular occlusive disease was examined.

RESULTS

87 cases of retinal vascular occlusive disease including 26 cases of retinal artery occlusion, 40 cases with central retinal vein occlusion, and 21 cases of branch retinal vein occlusion were compared with 87 age matched controls. Mean tHcy levels were higher in all disease groups and this difference was significant in patients with retinal artery occlusions (p= 0.032) and patients with central retinal vein occlusion (p=0.0001). When adjusted for known cardiovascular risk factors, tHcy was an independent risk factor for retinal vascular occlusive disease (OR 2.85 (95% CI 1.43-5.68)).

CONCLUSIONS

Elevated tHcy is an independent risk factor for retinal vascular occlusive disease. Assessment of tHcy may be important in the investigation and management of patients with retinal vascular occlusive disease.

Aortoduodenal fistula after endovascular stent-graft of an abdominal aortic aneurysm

Despite satisfying short- and middle-term effectiveness and feasibility, endovascular stent-grafting for abdominal aortic aneurysm is still under evaluation. We report a case of an aortoduodenal fistula after the use of this technique. Enlargement of the upper aneurysmal neck was followed by caudal migration of the major portion of the stent-graft, which resulted in kinking of the device in the aneurysmal sac. Ulcerations were found on adjacent portions of both the aneurysmal sac and the adjacent duodenum. Only the textile portion of the prosthetic contralateral limb separated the aortic lumen from the corresponding duodenal lumen. Early detection of complications after stent-grafting is essential to allow successful treatment, either surgical or endoluminal.

Research involving persons with cognitive impairments: results of a survey of Alzheimer disease research centers in the United States

Research involving persons with cognitive impairments presents ethical and practical challenges, including how to obtain valid informed consent. We asked the directors of the 29 U.S. research centers funded by the National Institute on Aging as "Alzheimer Disease Centers" to provide us with policies or guidelines used in their centers or associated institutions with regard to research involving cognitively impaired subjects. Twenty-four of the 29 centers (83%) responded. Five institutions (21%) had authored their own institutional policies, seven (29%) used guidelines issued by the Department of Health and Human Service's Office for Protection from Research Risks, and 12 (50%) had no policy or guidelines. The five institutional policies addressed a variety of issues, including obtaining consent from cognitively impaired subjects or their authorized representatives, subjects' assent to research participation, and guidance concerning determination of subjects' intellectual capacity. A well-written policy on the protection of cognitively impaired research subjects is one way a research institution demonstrates that it gives serious attention to the rights and welfare of these vulnerable persons. We recommend that all institutions conducting such research author written policies articulating appropriate safeguards for these vulnerable subjects. To promote the protection of cognitively impaired subjects, federal agencies and other funding groups may want to consider requiring written institutional policies as one condition of receiving funds to conduct such research.

Recurrence of cyclic esotropia after surgical correction

Cyclic esotropia is a rare form of strabismus in which a convergent squint appears and disappears typically, but not always, in a regular 48-hour cycle. Characteristically, the convergent squint, when present, has a large angle with associated suppression and no binocular function. On normal or "nonsquinting" days, no manifest deviation is detectable (although in some cases there may be an esophoria). Physiologic diplopia is appreciated, whereas fusion and stereopsis are all normal. Amblyopia may occur in up to 20% of cases.

Coats' disease of the retina (unilateral retinal telangiectasis) caused by somatic mutation in the NDP gene: a role for norrin in retinal angiogenesis

Coats' disease is characterized by abnormal retinal vascular development (so-called 'retinal telangiectasis') which results in massive intraretinal and subretinal lipid accumulation (exudative retinal detachment). The classical form of Coats' disease is almost invariably isolated, unilateral and seen in males. A female with a unilateral variant of Coats' disease gave birth to a son affected by Norrie disease. Both carried a missense mutation within the NDP gene on chromosome Xp11.2. Subsequently analysis of the retinas of nine enucleated eyes from males with Coats' disease demonstrated in one a somatic mutation in the NDP gene which was not present within non-retinal tissue. We suggest that Coats' telangiectasis is secondary to somatic mutation in the NDP gene which results in a deficiency of norrin (the protein product of the NDP gene) within the developing retina. This supports recent observations that the protein is critical for normal retinal vasculogenesis.

Ocular adnexal lymphoma-comparison of MALT lymphoma with other histological types

AIMS

To correlate histological features of ocular adnexal lymphoma using the revised European American lymphoma classification (REAL), with stage of disease at presentation, treatment modalities, and patient outcome. MALT lymphoma defines an extranodal marginal zone B cell lymphoma as outlined in the REAL classification. Comparison groups of patients included those with primary ocular adnexal MALT lymphoma versus primary ocular adnexal lymphomas of other types, MALT lymphoma versus non-MALT lymphomas (primary and secondary), and primary ocular adnexal lymphoma (MALT lymphomas and other types) versus secondary ocular adnexal lymphomas.

METHODS

A retrospective review of the National Ophthalmic Pathology Laboratory records identified 20 cases of ocular adnexal lymphoma over a 10 year period which were reclassified using appropriate immunohistochemical stains. Patients' medical records were examined for data including stage of the disease at presentation, mode of treatment, and patient outcome.

RESULTS

Among the 20 cases identified 14 had primary ocular adnexal lymphomas. 10 of the primary lymphomas had histological features of MALT lymphoma. One case was a primary ocular adnexal T cell lymphoma, one a follicular centre, follicular B cell lymphoma, and two were large cell B cell lymphomas. Six cases had systemic disease, four large B cell, one follicular centre, follicular B cell, and one mantle cell. A significantly higher proportion of patients with MALT lymphomas had early disease (p = 0.005), initially required local treatment (p = 0.005) and were alive at last follow up (p = 0.001) than those without. Two patients with MALT lymphoma had recurrence of lymphoma which responded to further treatment.

CONCLUSIONS

Patients with primary ocular adnexal MALT lymphomas present with localised disease requiring local treatment and have a better outcome compared with patients with other types. As a small percentage of these tumours recur, patients should be followed up indefinitely.

Long-term outcome of epikeratophakia

PURPOSE

To assess the long-term outcome of epikeratophakia.

SETTING

National center for pediatric ophthalmology (The Children's Hospital) and ophthalmology department in a regional general hospital (Waterford Regional Hospital), Republic of Ireland.

METHODS

A retrospective clinical review was carried out of 25 eyes (20 patients) with epikeratophakia performed over 10 years. Eyes were assigned to a children's group (Group 1) or an adult group (Group 2), depending on patient age at the time of surgery, and assessed with respect to indication for surgery, visual acuity, condition of the implanted lenticule, complications, refraction, and corneal topography. Histological analysis was performed on 1 removed lenticule.

RESULTS

Mean follow-up of all patients was 7.3 years (median 6.8 years; range 4.0 to 10.0 years). Most eyes (n = 18) were contact lens intolerant. Freeze-dried lenticules were implanted in all cases, and all but 1 had stable visual acuity from the early postoperative period to last follow-up. In Group 1 (n = 10), most eyes had a visual acuity of 6/36 or worse preoperatively with an improvement of 1 or more lines in 4 eyes. In Group 2 (n = 14), at last follow-up most eyes retained good or improved visual acuity by 1 or more lines. Most grafts were clear or had insignificant opacities outside the visual axis. The overall complication rate was 12%, with the most serious complication being significant induced astigmatism requiring removal of 1 epigraft. Mean induced astigmatism was 2.50 diopters (D) (median 2.00 D; range 1.00 to 6.00 D), which was accurately predicted within +/- 1.00 D by corneal topography in 14 of 19 eyes. Histology demonstrated infiltration of the implanted lenticule by host keratocytes.

CONCLUSION

Epikeratophakia, a reversible procedure with a low complication rate, resulted in stable visual acuity with good lenticule condition and minimal induced regular astigmatism after long-term follow-up.

Insulin-like growth factor-1 and growth hormone (GH) levels in canine cerebrospinal fluid are unaffected by GH or GH secretagogue (MK-0677) administration

Elevation in circulating GH levels results in a dose-related increase in serum insulin-like growth factor-1 (IGF-1) levels in dogs. However, it is not known whether elevations in systemic IGF-1 and GH levels contribute to the cerebrospinal fluid (CSF) levels of these hormones. Therefore, a study was designed in dogs to determine if elevated circulating GH levels was a result of a GH secretagogue (MK-0677) or if exogenous GH administration resulted in increased IGF-1 and GH levels in the CSF of dogs. A total of 12 normal, young adult male dogs were randomized to three treatment groups (4 dogs/group) based on body weight. There were 4 vehicle control dogs. A group of 4 dogs were dosed orally with MK-0677 (5 mg/kg/day) dissolved in deionized water. A third group of 4 dogs received subcutaneous injections of porcine GH (pGH) at a dose of 0.1 IU/kg/day. From all dogs, blood and CSF samples were collected prior to the initiation of treatment and on days 7 and 15 of treatment. All samples were assayed using a validated radioimmunoassay. Administration of MK-0677 or pGH resulted in a statistically significant (P < or = 0.05) increased body weight gain and increased serum IGF-1 and GH levels. In contrast, administration of MK-0677 resulted in no significant (P > 0.05) increase in CSF IGF-1 or GH levels on days 7 or 15 of the study. The CSF IGF-1 values ranged from 1.2 to 2.0 ng/ml with minimal variation among three separate samples taken during the course of the study from each dog. Similarly, the CSF GH levels were very low (< 0.98 ng/ml to 2.4 ng/ml) in all dogs irrespective of treatment group. This study has demonstrated that there is no correlation between the circulating levels of IGF-1 or GH and the levels of these hormones in the CSF of normal dogs. An approximately 100-fold difference between serum and CSF IGF-1 levels in vehicle control dogs suggest that there is a blood-brain barrier for the circulating IGF-1. Similarly, failure to see an elevation in CSF GH levels despite increases in serum GH levels shows that there is a blood-brain barrier for GH in normal dogs. These results suggest that the likely source of GH and IGF-1 in the CSF of dogs is from the CNS.

Isolation, characterization, and biological activity of naphthoquinones from Calceolaria andina L

Two compounds recognized as responsible for the insecticidal activity of extracts of Calceolaria andina L. (Scrophulariaceae) have been isolated and characterized as 2-(1, 1-dimethylprop-2-enyl)-3-hydroxy-1,4-naphthoquinone and the corresponding acetate, 2-acetoxy-3-(1,1-dimethylprop-2-enyl)-1, 4-naphthoquinone. Their activities against 29 pest species and 9 beneficial species of arthropod from a total of 11 orders have been determined. Activities against homopteran and acarine species are of the same order as those of established pesticides, and, significantly, no cross-resistance is observed for strains resistant to established classes of insecticide. Mammalian toxicities are low.

Reexamining the associate degree curriculum. Assessing the need for community concepts

Significant changes taking place in health care delivery in our community in Louisiana have led faculty to reexamine the associate degree nursing curriculum. We recognized the trend toward the decreased need for inpatient care and the greater need for outpatient care and home care in the community. In addition, we noted the need for nursing care to assist the elderly in the management of chronic illness and provide education on health promotion and disease prevention.

The use of clinical logs to improve nursing students' metacognition: a pilot study

The purpose of this study was to examine the effectiveness of the use of a reflective clinical log to improve students' thinking strategies and metacognition (cognitive awareness). Rather than prepare a written nursing care plan prior to entering the clinical setting, students instead were asked to write in a clinical log at the completion of their clinical day, reflecting upon client problems that they had identified, the data that were used to identify these problems, the nursing interventions that were used, and the results of these interventions. The students reported that they preferred the use of a reflective log over writing nursing care plans and they felt that the logs improved their ability to think about their thinking (i.e. their metacognition). The results of this pilot study indicate that reflection in clinical logs assists students to become more active learners, to manage their own thinking, and to improve their metacognition. Additional research in this area is needed to confirm study findings and to provide further understanding regarding the effectiveness of clinical logs as a teaching strategy to improve students' metacognition.

Assessing the value of a new pharmaceutical. A feasibility study of contingent valuation in managed care

OBJECTIVES

The authors assessed the feasibility and construct validity of the contingent valuation method for measuring the monetary value to healthy enrollees in a health maintenance organization of a new drug, filgrastim, as prophylaxis against febrile neutropenia after chemotherapy treatment for cancer.

METHODS

A random sample of 220 enrollees from a closed-panel staff-model health maintenance organization who did not have cancer were interviewed. Chemotherapy, febrile neutropenia and filgrastim were described by video and decision board. Questions were asked in two different scenarios: (1) User-based: Assuming they were at the point of consumption and about to receive chemotherapy, what is the maximum they would be willing to pay to receive filgrastim? and (2) Insurance-based: Given they were at risk of cancer in the future, what is the maximum they would be willing to pay in additional monthly insurance premiums to add filgrastim to the plan? In a second insurance scenario where respondents were told that filgrastim was covered, what is the minimum reduction in premium that persons were willing to accept to relinquish coverage of the drug? A 2 x 2 factorial design was used to contrast two bidding algorithms to test for starting point bias and two 5-yearly prior risks of cancer, 1/200 versus 1/100. Main effects were tested by ANCOVA controlling for age, sex, health, and income.

RESULTS

Demographics of experimental cells were similar. No evidence was found of significant starting point bias. For user-based questions, as expected, willingness-to-pay increases with febrile neutropenia risk reduction, but at a declining marginal rate. Despite careful presentation of information to respondents, willingness-to-pay for insurance was higher in the lower prior risk group. Consistent with previous contingent valuation studies, the authors of the present study found evidence that willingness-to-accept exceeds willingness-to-pay for coverage of the same benefit.

CONCLUSIONS

An insurance-based contingent valuation study is feasible in a health maintenance organization. Construct validation evidence was encouraging, with the exception of the test for prior risk of cancer; however, this was a between-person contrast and may have been confounded by other factors.

Prevalence of diabetic retinopathy in patients with diabetes mellitus diagnosed after the age of 70 years

AIMS/BACKGROUND

A hospital based prevalence study was undertaken to estimate the prevalence of diabetic retinopathy (DR) in patients diagnosed as having diabetes mellitus after the age of 70 years. The prevalence of visually threatening retinopathy at the time of diagnosis of diabetes was also determined. The association between prevalence of DR and duration of diabetes mellitus, mode of treatment, HbA1c levels, presence of hypertension, and sex of patient was examined and a comparison was drawn between this study and earlier prevalence studies of DR in older type II diabetics.

METHODS

Using data on the Irish Diabetic Retinopathy Register located in the Mater Misericordiae Hospital, Dublin, all patients who were diagnosed as having type II diabetes mellitus after the age of 70 years were invited to attend for ophthalmic review. Medical records were examined to determine the duration of diabetes mellitus, mode of treatment, recent HbA1c levels, and the presence of systemic hypertension.

RESULTS

Of the 150 patients examined, 21 (14%) had some form of DR and 10 of these patients (6.6%) had visually threatening retinopathy or previously treated visually threatening retinopathy. Five patients (3.3%) presented with visually threatening retinopathy at the time of diagnosis of diabetes. Those patients with DR had a significantly higher median duration of diabetes (5.0 years) compared with those patients without DR (3.5 years). A significantly higher proportion of patients with DR required treatment with insulin and a correspondingly lower proportion of patients without DR were controlled on diet alone. There was no significant association between prevalence of DR and HbA1c levels, systemic hypertension, or sex of patient. There was a lower overall prevalence of DR in comparison with earlier studies.

CONCLUSIONS

The prevalence of DR in these elderly type II diabetics is lower than than previously reported in patients with type II disease but a small percentage of patients had visually threatening retinopathy at presentation. Longer duration of diabetes and insulin use were associated with a significantly increased prevalence of DR. All elderly type II diabetic patients require thorough ophthalmic examination near to the time of first presentation and thereafter at regular intervals.

Chrysiogenes arsenatis gen. nov., sp. nov., a new arsenate-respiring bacterium isolated from gold mine wastewater

A new strictly anaerobic bacterium (strain BAL-1T) has been isolated from a reed bed at Ballarat Goldfields in Australia. The organism grew by reducing arsenate [As(V)] to arsenite [As(III)], using acetate as the electron donor and carbon source; acetate alone did not support growth. When BAL-1T was grown with arsenate as the terminal electron acceptor, acetate could be replaced by pyruvate, L- and D-lactate, succinate, malate, and fumarate but not by H2, formate, citrate, glutamate, other amino acids, sugars, or benzoate. When acetate was the electron donor, arsenate could be replaced by nitrate or nitrite but not by sulfate, thiosulfate, or iron oxide. Nitrate was reduced to ammonia via nitrite. The doubling time for growth on acetate (5 mM) plus arsenate (5 mM) or nitrate (5 mM) was 4 h. The G+C content of the DNA is 49 mol%. The 16S rRNA sequence data for the organism support the hypothesis that this organism is phylogenetically unique and at present is the first representative of a new deeply branching lineage of the Bacteria. This organism is described as Chrysiogenes arsenatis gen. nov., sp. nov.