Harnessing translational research in wheat for climate resilience

Despite being the world's most widely grown crop, research investments in wheat (Triticum aestivum and Triticum durum) fall behind those in other staple crops. Current yield gains will not meet 2050 needs, and climate stresses compound this challenge. However, there is good evidence that heat and drought resilience can be boosted through translating promising ideas into novel breeding technologies using powerful new tools in genetics and remote sensing, for example. Such technologies can also be applied to identify climate resilience traits from among the vast and largely untapped reserve of wheat genetic resources in collections worldwide. This review describes multi-pronged research opportunities at the focus of the Heat and Drought Wheat Improvement Consortium (coordinated by CIMMYT), which together create a pipeline to boost heat and drought resilience, specifically: improving crop design targets using big data approaches; developing phenomic tools for field-based screening and research; applying genomic technologies to elucidate the bases of climate resilience traits; and applying these outputs in developing next-generation breeding methods. The global impact of these outputs will be validated through the International Wheat Improvement Network, a global germplasm development and testing system that contributes key productivity traits to approximately half of the global wheat-growing area.

Electrokinetic device design and constraints for use in high conductance solutions

The quest for new cell-free DNA and exosome biomarker-based molecular diagnostics require fast and efficient sample preparation techniques. Conventional methods for isolating these biomarkers from blood are both time-consuming and laborious. New electrokinetic microarray devices using dielectrophoresis (DEP) to isolate cell-free DNA and exosome biomarkers have now greatly improved the sample preparation process. Nevertheless, these devices still have some limitations when used with high conductance biological fluids, e.g. blood, plasma, and serum. This study demonstrates that electrochemical damage may occur on the platinum electrodes of DEP microarray devices. It further examines two model device designs that include a parallel wire arrangement and a planar array. Effective isolation of fluorescent beads with parallel wires is shown under low-conductance conditions (10^-4  S/m), but electrothermal flow overcomes DEP forces under high conductance conditions (>0.1 S/m). Planar devices are shown to be effective under high conductance conditions (∼1 S/m) without the deleterious effects of electrothermal flow. This study provides new insights into design compromises and limitations for producing future electrokinetic devices for better performance with high conductance solutions.

Managing potential drug-drug interactions between gastric acid-reducing agents and antiretroviral therapy: experience from a large HIV-positive cohort

Drug-drug interactions between antiretroviral therapy and other drugs are well described. Gastric acid-reducing agents are one such class. However, few data exist regarding the frequency of and indications for prescription, nor risk assessment in the setting of an HIV cohort receiving antiretroviral therapy. To assess prevalence of prescription of gastric acid-reducing agents and drug-drug interaction within a UK HIV cohort, we reviewed patient records for the whole cohort, assessing demographic data, frequency and reason for prescription of gastric acid-reducing therapy. Furthermore, we noted potential drug-drug interaction and whether risk had been documented and mitigated. Of 701 patients on antiretroviral therapy, 67 (9.6%) were prescribed gastric acid-reducing therapy. Of these, the majority (59/67 [88.1%]) were prescribed proton pump inhibitors. We identified four potential drug-drug interactions, which were appropriately managed by temporally separating the administration of gastric acid-reducing agent and antiretroviral therapy, and all four of these patients remained virally suppressed. Gastric acid-reducing therapy, in particular proton pump inhibitor therapy, appears common in patients prescribed antiretroviral therapy. Whilst there remains a paucity of published data, our findings are comparable to those in other European cohorts. Pharmacovigilance of drug-drug interactions in HIV-positive patients is vital. Education of patients and staff, and accurate data-gathering tools, will enhance patient safety.

Physicochemical properties of ferumoxytol, a new intravenous iron preparation

BACKGROUND

Intravenous iron is a critical component of anaemia management. However, currently available preparations have been associated with the release of free iron, a promoter of bacterial growth and oxidative stress.

MATERIALS AND METHODS

We determined the molecular weight, dialysability and capacity for free iron release of ferumoxytol, a semi-synthetic carbohydrate-coated superparamagnetic iron oxide nanoparticle. Ferumoxytol was compared with three intravenous iron preparations in clinical use: iron dextran (low molecular weight), sodium ferric gluconate and iron sucrose. Intravenous iron preparations were also incubated in rat, and pooled human sera (at concentrations of 600 microM and 42 microg mL(-1) respectively) from healthy subjects.

RESULTS

The molecular weight of ferumoxytol was 731 kDa. The relative order of molecular weight was as follows: ferumoxytol > iron dextran > iron sucrose > sodium ferric gluconate. The least ultrafilterable iron was observed with ferumoxytol and the most with ferric gluconate. The least dialysable free iron was observed with ferumoxytol and the most with ferric gluconate. Incubation of intravenous iron preparations in rat or pooled human sera demonstrated minimal free iron release with ferumoxytol. The order of catalytic iron release as detected by the bleomycin detectable iron assay was as follows: ferumoxytol < iron dextran < iron sucrose < ferric gluconate. A similar trend was observed for the in vivo serum concentration of free iron in rats.

CONCLUSIONS

In vitro observations from these experiments suggest that ferumoxytol has a favourable profile in terms of tendency to release free iron, in comparison with currently available intravenous iron preparations.

Effect of institution-wide policy of colonoscopy withdrawal time > or = 7 minutes on polyp detection

BACKGROUND & AIMS

Practice guidelines recommend that endoscopists spend at least 7 minutes examining the colonic mucosa during colonoscopy withdrawal to optimize polyp yield. The aim of this study was to determine if the implementation of an institution-wide policy of colonoscopy withdrawal time > or = 7 minutes was associated with an increase in colon polyp detection.

METHODS

All 42 endoscopists at our institute were asked to attain a colonoscopy withdrawal time of at least 7 minutes. Compliance with 7-minute withdrawal time was recorded for all nontherapeutic colonoscopies. Polyp detection ratio (number of polyps detected divided by number of colonoscopies performed) was computed. Regression models were used to assess the association between compliance with 7-minute withdrawal time and polyp detection.

RESULTS

During the study period, 23,910 colonoscopies were performed. The average age of patients was 56.8 years, and 54% were female. Colon cancer screening or surveillance was the indication for 42.5% of colonoscopies. At the beginning of the study, the polyp detection ratio was 0.48. Compliance with 7-minute withdrawal time for nontherapeutic procedures increased from 65% at the beginning of the initiative to almost 100%. However, no increase in polyp detection ratio was noted over the same period for all polyps (slope, 0.0006; P = .45) or for polyps 1-5 mm (slope, 0.001; P = .26), 6-9 mm (slope, 0.002; P = .43), or > or = 10 mm (slope, 0.006; P = .13). No association was detected when only colonoscopies performed for screening or surveillance were analyzed.

CONCLUSIONS

An institution-wide policy of colonoscopy withdrawal time > or = 7 minutes had no effect on colon polyp detection.

Cognitive impairments in relapsing-remitting multiple sclerosis: a meta-analysis

There is debate in the literature regarding the magnitude, nature, and influence of cognitive impairment in individuals with relapsing-remitting multiple sclerosis (RRMS). Therefore, we conducted a meta-analysis that quantified the overall magnitude of cognitive impairment in individuals with RRMS and identified the domains of cognition and clinical/demographic variables that were moderators of the overall effect. We included 57 studies with 3891 participants that yielded a total of 755 effect sizes. Overall, there was a moderate decline in cognitive functioning in individuals with RRMS compared with healthy controls. Larger effects were observed in cognitive domains of motor functioning, mood status and memory and learning. Regarding demographic and clinical variables, age and gender were moderators of cognitive impairment in all cognitive domains, whereas neurological disability and disease duration primarily moderated performance on tasks assessing memory and learning.

Overexpression of the maize Teosinte Branched1 gene in wheat suppresses tiller development

The number of viable shoots influences the overall architecture and productivity of wheat (Triticum aestivum L.). The development of lateral branches, or tillers, largely determines the resultant canopy. Tillers develop from the outgrowth of axillary buds, which form in leaf axils at the crown of the plant. Tiller number can be reduced if axillary buds are not formed or if the outgrowth of these buds is restricted. The teosinte branched1 (tb1) gene in maize, and homologs in rice and Arabidopsis, genetically regulate vegetative branching. In maize, increased expression of the tb1 gene restricts the outgrowth of axillary buds into lateral branches. In this study, the maize tb1 gene was introduced through transformation into the wheat cultivar "Bobwhite" to determine the effect of tb1 overexpression on wheat shoot architecture. Examination of multiple generations of plants reveals that tb1 overexpression in wheat results in reduced tiller and spike number. In addition, the number of spikelets on the spike and leaf number were significantly greater in tb1-expressing plants, and the height of these plants was also reduced. These data reveal that the function of the tb1 gene and genetic regulation of lateral branching via the tb1 mode of action is conserved between wheat, rice, maize and Arabidopsis. Thus, the tb1 gene can be used to alter plant architecture in agriculturally important crops like wheat.

Responses to hypoxia and recovery: repayment of oxygen debt is not associated with compensatory protein synthesis in the Amazonian cichlid,Astronotus ocellatus

Oxygen consumption, as an indicator of routine metabolic rate (RoMR), and tissue-specific changes in protein synthesis, as measured by 3H-labelled phenylalanine incorporation rates, were determined in Astronotus ocellatus to investigate the cellular mechanisms behind hypoxia-induced metabolic depression and recovery. RoMR was significantly depressed, by approximately 50%, when dissolved oxygen levels reached 10%saturation (0.67±0.01 mg l–1 at 28±1°C). This depression in RoMR was accompanied by a 50–60% decrease in liver,heart and gill protein synthesis, but only a 30% decrease in brain protein synthesis. During recovery from hypoxia, an overshoot in RoMR to 270% of the normoxic rate was observed, indicating the accumulation of an oxygen debt during hypoxia. This conclusion was consistent with significant increase in plasma lactate levels during the hypoxic exposure, and the fact that lactate levels rapidly returned to pre-hypoxic levels. In contrast, a hyperactivation of protein synthesis did not occur, suggesting the overshoot in oxygen consumption during recovery is attributed to an increase in cellular processes other than protein synthesis.

Oral toxicity study of 2-pentenenitrile in rats with reproductive toxicity screening test

A combined repeated-dose toxicity study with reproduction was conducted with 2-pentenenitrile (2-PN). Rats (10/sex per dose level) were dosed with 2-PN once daily by gavage at dose levels of either 0, 1, 3, or 10 mg kg(-1) day(-1) for 28 days, prior to and during cohabitation, and through day 3 of lactation. General clinical observations were recorded daily; body weights were recorded weekly. A neurobehavioral evaluation consisting of a functional observational battery and motor activity was conducted in all parental rats (10/sex per group). Clinical pathology parameters (hematology, clinical chemistry, coagulation) were measured in parental rats. Pup weights and clinical signs were recorded at birth and on lactation day 4. Parental rats were given a gross pathological examination, organ weights were obtained, and histological examination was conducted for the control and 10 mg kg(-1) day(-1) groups. No effects were seen with regard to mortality, clinical signs, functional observational battery and motor activity, hematology, or organ weights. Females receiving 10 mg/kg and males from all dose groups showed lower body weight gains and feed efficiency. Increased albumin concentrations were seen in both sexes given 10 mg/kg. Females in the 10 mg/kg group showed degeneration of the olfactory mucosa. No effects on the numbers of pups born, number surviving to lactation day 4, pup weight, and no gross anatomical development changes were observed. Under the conditions of this study, the no-observed-effect level (NOEL) for systemic toxicity in rats was 3 mg kg(-1) day(-1), based on degeneration of olfactory mucosa in females at 10 mg kg(-1) day(-1). The NOEL for reproductive and neurobehavioral toxicity in rats and for toxicity to offspring was 10 mg kg(-1) day(-1), the highest dose level tested.

Cystoid macular oedema following pneumatic retinopexy vs scleral buckling

AIMS

To determine the incidence of angiographic cystoid macular oedema (CMO) following pneumatic retinopexy (PR) and scleral buckling (SB) in consecutive case series.

METHODS

Patients who had successful anatomical attachment following PR and SB were included in our study; 132 patients had PR and 121 patients had SB. We evaluated the demographic characteristics, visual acuity, lens status, macular status, and previous ocular history in all patients. CMO was evaluated by fluorescein angiography (FA) in a masked pattern, 6 and 12 weeks after surgery in all cases. We analysed the CMO incidence and its correlation with preoperative ocular status and visual outcome. Chi2 and Fisher's exact tests were used in statistical analysis.

RESULTS

CMO was present in 15 of 132 (11%) PR, and 35 of 121 (29%) SB patients at 6 weeks (P=0.0005); the oedema was persistent in eight of 132 (6%) PR and 21 of 121 (17%) SB patients at 12 weeks (P=0.0005). Eight of 106 (8%) phakic and seven of 26 (27%) pseudophakic patients developed CMO following PR (P=0.02). In the SB group, 26 of 72 (36%) patients who had preoperative macular detachment developed CMO (P=0.03). Visual improvement was limited in patients who developed angiographic CMO despite anatomical re-attachment of the retina.

CONCLUSIONS

CMO may occur following both PR and SB and deteriorate the visual outcome. Previous cataract surgery and macular detachment may increase the CMO rates following PR and SB, respectively.

Comparison of liver enzymes in osmerid fishes: key differences between a glycerol accumulating species, rainbow smelt (Osmerus mordax), and a species that does not accumulate glycerol, capelin (Mallotus villosus)

Activities of enzymes associated with glycerol synthesis were compared in the liver of two osmerid fishes, the smelt (Osmerus mordax), which can accumulate high (400 mM) levels of glycerol and capelin (Mallotus villosus) that does not accumulate glycerol. Animals were sampled at approximately the same time of year and temperature thus negating potential seasonal effects. These species are closely related, reducing interpretative issues involving comparison between unrelated species. We found that key enzyme activities were elevated in the smelt relative to the non-glycerol accumulating capelin, namely enzymes involved with glycolysis (phosphofructose kinase-1 and aldolase), amino acid metabolism (aspartate aminotransferase and alanine aminotransferase), gluconeogenesis (phosphoenolpyruvate carboxykinase) and glycerol synthesis (glycerol-3-phosphate dehydrogenase). The enzyme profiles strongly support the hypothesis that smelt can synthesize glycerol by utilizing glycogen and amino acids as the carbon source and that they have increased capacity for metabolic flux through loci required for synthesis of the three carbon intermediate dihydroxyacetone phosphate and subsequently glycerol synthesis.

MR imaging of murine arthritis using ultrasmall superparamagnetic iron oxide particles

The objective of this work was to determine the ability of magnetic resonance (MR) imaging with ultrasmall superparamagnetic iron oxide (USPIO) particles to provide quantitative measures of inflammation in autoimmune arthritis. Mice were injected intravenously or intra-articularly with USPIO followed by magnetic resonance and histological assessment of the knee joint. Comparisons were made between MR microimages and histology in naïve mice and mice with collagen-induced arthritis.Following intravenous administration, accumulation of USPIO was observed in the popliteal lymph nodes, but not the joint. Administration of USPIO intra-articularly resulted in signal loss in the joint. The MR signal intensity could be quantified and correlated with iron staining in the synovial lining. A marked increase in USPIO uptake and a corresponding decrease in signal intensity were observed in arthritic, compared to naïve mice. Areas of focal signal loss corresponded to foci of iron staining by histology. These studies may provide a basis for the clinical application of USPIO in arthritis for assessing disease severity and monitoring response to therapy.

Interstitial MR lymphangiography for the detection of sentinel lymph nodes

BACKGROUND AND OBJECTIVES

The challenge for implementation of sentinel lymph node biopsy is to develop a reliable minimally invasive technique that identifies all possible sentinel nodes with high temporal and spatial resolution. This study evaluated the use of a magnetic resonance imaging (MRI) contrast agent (USPIO) for preoperative sentinel node detection.

METHODS

Anesthetized pigs received interstitial or intradermal injections of ultra small superparamagnetic of iron oxide (USPIO) (0.2 or 5 mg Fe) in the L/R posterior tongue and stifles (knee) respectively. MRI was done before, during injection and at 0.25, 0.5, 1, 2, 4, 6, 24, and 48 hr after which isosulfan blue sentinel node mapping was done.

RESULTS

In the tongue, both doses of USPIO identified the sentinel node in the early images. No additional nodes were detected by MR at 24 or 48 hr. In the hind limb, sentinel nodes identified on the early MR images were also identified by the isosulfan blue. In both locations, the higher dose also identified secondary nodes some of which were also identified by the isosulfan blue. All sentinel nodes that were identified by USPIO on MRI were noted to be stained brown at the time of dissection.

CONCLUSIONS

Interstitial MR lymphangiography is a useful technique for the detection of sentinel lymph nodes. This method provides excellent simultaneous temporal and spatial resolution, is minimally invasive, and can be performed preoperatively.

Regulation of cutaneous malignancy by gammadelta T cells

The localization of gammadelta T cells within epithelia suggests that these cells may contribute to the down-regulation of epithelial malignancies. We report that mice lacking gammadelta cells are highly susceptible to multiple regimens of cutaneous carcinogenesis. After exposure to carcinogens, skin cells expressed Rae-1 and H60, major histocompatibility complex-related molecules structurally resembling human MICA. Each of these is a ligand for NKG2d, a receptor expressed by cytolytic T cells and natural killer (NK) cells. In vitro, skin-associated NKG2d+ gammadelta cells killed skin carcinoma cells by a mechanism that was sensitive to blocking NKG2d engagement. Thus, local T cells may use evolutionarily conserved proteins to negatively regulate malignancy.

Quality of care among elderly patients hospitalized with unstable angina

BACKGROUND

Guidelines for the management of unstable angina have been published by the United States Agency for Health Care Policy and Research (currently known as the Agency for Healthcare Research and Quality); however, little information is available about the quality of unstable angina care, particularly among elderly patients.

METHODS

We examined 1196 elderly Medicare-insured patients hospitalized with unstable angina (ruled out for acute myocardial infarction) at Connecticut hospitals between August and November 1995 to evaluate quality of care provided during hospitalization. Patients without therapeutic contraindications were evaluated for the use of 5 Agency for Health Care Policy and Research guideline-recommended measures: electrocardiographic examination within 20 minutes of admission, use of aspirin on admission, intravenous heparin on admission, achievement of therapeutic anticoagulation among patients provided heparin, and prescription of aspirin on discharge.

RESULTS

Less than half (49.6%) of patients underwent electrocardiographic examination within 20 minutes of admission. After excluding patients with contraindications, aspirin was provided to 80.1% of patients and intravenous heparin to 59.2% of indicated patients, of whom only 43.3% achieved therapeutic anticoagulation. Aspirin was prescribed to 82.3% of eligible patients at discharge. Performance on the 5 quality measures varied widely among hospitals.

CONCLUSIONS

Agency for Health Care Policy and Research guideline-recommended risk stratification and therapeutic interventions are underused in elderly patients hospitalized with unstable angina, with quality of care varying widely among hospitals.

HTLV-I-associated granulomatous T-cell lymphoma in a child

Adult T-cell leukemia/lymphoma (ATLL) is a T-cell malignancy closely associated with human T-cell lymphotropic virus-1 (HTLV-I). Because of its long latency period, ATLL occurs almost exclusively in adults. We report a case of a 13-year-old boy with an 8-year history of skin eruptions. After complete evaluation, a diagnosis of HTLV-I-associated lymphoma/leukemia was made. The T-cell lymphoma exhibited a granulomatous histomorphology. There have been very few reports of ATLL presenting in childhood and none, to our knowledge, demonstrating granulomatous histology. We conclude that ATLL may rarely present as a chronic granulomatous eruption in a child.

Soccer ball-related retinal injuries: a report of 13 cases

PURPOSE

To describe the clinical characteristics and management of retinal injuries caused by soccer ball impact as well as the mechanism of injury, prognostic features, risk factors, and possible prevention strategies.

METHODS

Thirteen cases of soccer ball injuries from retina referral practices were retrospectively reviewed, with attention to the mechanism of associated ocular complications and the anatomic and visual outcomes.

RESULTS

Soccer ball injuries occurred in both male and female patients (9 male, 4 female) with ages ranging from 8 to 21 years (median 14 years). These patients were observed from 0 to 64 months (median follow-up, 8 months). Four patients had traumatic macular holes, two eyes had retinal detachment associated with retinal dialysis, two had retinal tears associated with hemorrhage, one had a choroidal rupture, and one had only vitreous hemorrhage and Berlin's edema. Although six eyes had some degree of traumatic retinal pigment epitheliopathy, it was the primary diagnosis in only three. Visual acuity at presentation ranged from 20/20 to count fingers, with 7/13 (54%) having 20/200 or worse vision. Seven eyes underwent surgical procedures; the remainder were observed. Final visions ranged from 20/20 to count fingers, with 3/13 (23%) having 20/200 or worse vision. Six eyes (46%) improved by two or more lines by the last follow-up.

CONCLUSION

Soccer ball-related ocular injuries disproportionately affect young players, are more frequent in females than previously reported, and have more severe visual consequences than previously recognized. Injury prevention strategies to minimize contact between the eye and the soccer ball may reduce the incidence and severity of eye injuries.

Repairing the bond in important relationships: a dynamic for personality maturation

OBJECTIVE

The author sought to establish a common set of interactional dynamics involved in growth-facilitating interpersonal relationships.

METHOD

Empirical studies of the three most common dyadic relationships associated with personality growth were reviewed: infant-mother attachment behaviors, the psychotherapeutic alliance, and the marital relationship.

RESULTS

Empirical and clinical studies support the conclusion that growth is facilitated when a strong affective bond is established with an important other and the inevitable disruptions of this bond are repaired.

CONCLUSIONS

Personality maturation across the lifespan has been attributed to the internalization of admirable qualities of important others. The data surveyed suggest that the interactional dynamics associated with internalization involve establishing a strong affective bond with an important other and repairing this bond's inevitable ruptures. It is both the rupture and the repair that are crucial.

The c-Abl tyrosine kinase contributes to the transient activation of MAP kinase in cells plated on fibronectin

Previous work showed that integrin stimulation triggers activation of the c-Abl tyrosine kinase and its transient localization to focal adhesions. We now report that plating cells on fibronectin triggers association of Grb2 with c-Abl, suggesting possible involvement of c-Abl with integrin activation of the MAP kinase pathway. Expression of a kinase-defective c-Abl specifically inhibited the transient induction of Erk2 activity following cell adhesion. Together with the known ability of activated, oncogenic forms of c-Abl to activate Ras and the MAP kinase pathway, these data suggest that c-Abl contributes to the integrin induction of MAP kinase activity.

Food service in long day care centres--an opportunity for public health intervention

OBJECTIVE

To determine the characteristics of long day care centre operations, food service management practices, and nutrition resources use and needs.

METHOD

In October 1996, all 330 long day care centres in Western Australia were surveyed by telephone to gather information to help develop strategies for food service improvement.

RESULTS

The response rate was 85%. An accreditation committee directed operations in 76% of centres. Most centres employed a cook with limited or no cooking training. Coordinators identified training needs for cooks that are specific to the National Childcare Accreditation Council's Quality Improvement and Accreditation System (QIAS) guidelines: food hygiene; nutritional and food requirements of children; menu planning; and multicultural cooking.

CONCLUSIONS

National standards for the quantification of foods to meet children's nutritional requirements in long day care would allow for consistency in educating child care workers, training cooks, and establishing and assessing government regulations and the QIAS guidelines. Nine recommendations for strategies to improve food service in long day care are presented.

IMPLICATIONS

There are two main messages for public health practitioners working to improve the quality of food served to children in long day care: the strong influence of the QIAS guidelines, and the need for specific nutrition recommendations.

Nonvitrectomizing vitreous surgery: a strategy to prevent postoperative nuclear sclerosis

OBJECTIVE

The development or progression of postoperative nuclear sclerosis is the most common complication of successful vitrectomy in elderly patients. The authors treated idiopathic epimacular proliferation (EMP) with nonvitrectomizing vitreous surgery in an attempt to prevent postoperative nuclear sclerosis.

DESIGN

Prospective, nonrandomized, comparative case series.

PARTICIPANTS

The authors surgically removed membranes from the sensory retina in 21 eyes of 21 patients with EMP.

INTERVENTION

Neither intravitreal infusion nor vitrectomy of any kind was performed during the procedure. The peeled membrane was left floating in the vitreous cavity in 11 (group 1) eyes and removed in 10 eyes (group 2). Nonoperated fellow eyes served as controls.

MAIN OUTCOME MEASURES

Visual acuity, slit-lamp and/or Scheimpflug photography, and refractometry were performed pre- and postoperatively to evaluate changes in the degree of lenticular opacity.

RESULTS

There was no difference in the rate of development or progression of nuclear sclerosis or the degree of myopic shift between operated and control eyes during the postoperative follow-up period (mean, 9.7 months). No serious complications were noted. There was no difference in postoperative course between patients in the two operative groups.

CONCLUSIONS

Although interpretation of the results of this study is limited due to its small size and short follow-up, nonvitrectomizing vitreous surgery seems to decrease the postoperative development or progression of nuclear sclerosis in patients with idiopathic EMP.

Change in retinal sensitivity due to excision of choroidal neovascularization and its influence on visual acuity outcome

PURPOSE

Excision of choroidal neovascular membranes (CNV) has been attempted as an alternative to photocoagulation for the management of subfoveal CNV. To evaluate functional results of CNV excision, we studied retinal sensitivity in the area corresponding to the CNV (CNV area).

METHODS

Static microperimetry using a scanning laser ophthalmoscope was performed on 17 eyes before and after CNV excision. We studied whether CNV excision changed retinal sensitivity in the CNV area. To evaluate the relationship between retinal sensitivity and visual acuity, further testing was performed on nine patients who had subfoveal CNV from age-related macular degeneration (ARMD).

RESULTS

Preoperatively, 5 of 17 eyes (29.4%) had retinal sensitivity in the CNV area. Postoperatively, 4 of 17 (23.5%) eyes had retinal sensitivity. Surgery did not significantly change retinal sensitivity in the CNV area (P>0.999). There was a significant correlation between the presence of retinal sensitivity and visual acuity. Postoperative visual acuity of eyes with retinal sensitivity in the CNV area was better than that of the eyes without sensitivity in the patients with subfoveal CNV from ARMD (P = 0.0017).

CONCLUSIONS

In most cases, excision of CNV does not improve central retinal sensitivity, and patients have poor visual outcome. In some cases, however, postoperative sensitivity in the bed of CNV is preserved and visual outcome is relatively good. Better or worse preoperative retinal sensitivity does not predict better or worse visual acuity outcome, respectively.

Medicine, economics and agenda-setting

The filtering of potential policy issues from a large range of possibilities to a relatively small list of agenda items allows the organisation of power and influence within a policy sector to be examined. This study investigated power and influence in health policy agenda-setting in one State of Australia (Victoria) in the years 1991, 1992 and 1993. The actors seen as influential were predominantly medically trained and working in academia, health bureaucracies and public teaching hospitals. This research supports an elite model of health policy agenda-setting, in which outcomes are dependent on the structured interests within the policy field. However, while the corporate elite of the profession is influential, the frontline service providers are not, as indicated by the location of influentials in large and prestigious organisations. Politicians and professional associations and unions are less well represented, and consumer and community groups are virtually absent. In 1993 there was a sharp increase in economists being nominated as influentials, with a subsequent decrease in influentials with medical training. This relates to a (perceived or real) shift in influence from the medical profession to senior health bureaucrats. Economic concerns appear to be shaping the visible health policy agenda, through an increased number of influentials with economics training, but also through an apparent ability to shape the issues that other influentials are adding as agenda items. The corporate elite of medicine remains powerful, but their range of concerns has been effectively limited to cost containment or cost reduction, better planning and efficiency. This limiting of concerns occurs within an international policy context, where the general trends of globalisation and an emphasis on neo-liberal economics impact on the direction of health policy in individual countries.

Pneumatic displacement of subretinal hemorrhage without tissue plasminogen activator

OBJECTIVE

To assess the efficacy and complications of intravitreal injection of perfluoropropane gas for displacement of subretinal hemorrhage (SRH), without the use of tissue plasminogen activator.

PATIENTS AND METHODS

Pure perfluoropropane gas (0.4-0.5 mL) was injected into the vitreous cavity in 5 patients with SRH involving the fovea because of age-related macular degeneration (4 eyes) or ruptured retinal arterial macroaneurysm (1 eye). The patients were instructed to maintain a prone position.

RESULTS

Visual acuity ranged from 20/300 to 20/2000 before gas injection. On the day after gas injection, SRH was dramatically displaced in 3 eyes and slightly displaced with a reduction in the thickness of subfoveal hemorrhage in the remaining 2 eyes. Final visual acuity improved in all cases, ranging from 20/15 to 20/220. Three eyes had a final visual acuity of 20/50 or better. Vitreous hemorrhage caused by migration of SRH into the vitreous cavity and retinal detachment each occurred in 1 eye, and both complications were successfully treated by vitrectomy.

CONCLUSIONS

Gas injected into the vitreous cavity can displace SRH without the use of tissue plasminogen activator in some cases. Visual acuity after gas injection may be improved, making this treatment an alternative to evacuation of SRH with vitrectomy.

Chorioretinal damage caused by the excision of choroidal neovascularization

PURPOSE

To determine whether choroidal neovascularization excision causes mechanical damage to the neurosensory retina, retinal pigment epithelium, or choriocapillaris.

METHODS

Prospectively, 18 eyes of 18 consecutive patients who underwent choroidal neovascularization excision were observed. Preoperatively and postoperatively, the integrity of the choriocapillaris circulation in the pathway of choroidal neovascularization extraction was studied by fluorescein and indocyanine green angiography. Using static scanning laser ophthalmoscope microperimetry, the presence of iatrogenic scotomas that developed postoperatively in the pathway of choroidal neovascularization extraction was also investigated.

RESULTS

Postoperatively, a choriocapillaris defect was detected in 17 (94.4%) of 18 cases. In 15 cases (83.3%), the choriocapillaris defect had a clear relationship to the pathway of choroidal neovascularization extraction. Postoperatively, a scotoma was present in 16 (88.9%) of 18 cases. In 14 cases (77.8%), the location of the scotoma had a clear relationship to the pathway of choroidal neovascularization extraction.

CONCLUSION

Surgical excision of choroidal neovascularization leads to severe damage of the choroid and retina in the pathway of the extracted choroidal neovascularization. The injury involves the neurosensory retina, retinal pigment epithelium, and choriocapillaris.

Integrins regulate the association and phosphorylation of paxillin by c-Abl

The c-Abl proto-oncogene is a non-receptor tyrosine kinase whose activity and localization are regulated by integrins. Cell adhesion to fibronectin triggers the transient recruitment of c-Abl from the nucleus to focal adhesions and activation of its tyrosine kinase. To investigate the integrin regulation of c-Abl, proteins that interact with c-Abl following cell adhesion were assayed. Several proteins that were phosphorylated on tyrosine were found to transiently co-precipitate with c-Abl during cell adhesion, and one was identified as the focal adhesion protein paxillin. Abl also became transiently phosphorylated in response to cell adhesion. In addition, paxillin was found to serve as substrate for the adhesion-activated c-Abl kinase. These results suggest that c-Abl may mediate effects of integrins on cell functions by phosphorylating paxillin.

For better or worse: interpersonal relationships and individual outcome

At a time of strong biological emphasis in psychiatry, it is important to emphasize that relationships with important others may play a crucial role in individual outcome. Psychoanalytic theories in the form of object relations, self psychology, and relational psychoanalysis reflect this emphasis, and at a broader level, the interpersonal school of psychiatry focuses selectively on the role of relationships in health and illness. Ten central premises of the interpersonal school are presented, followed by brief, selective reviews of three bodies of empirical data: studies of well-functioning marriages and families, the role of adult relationships in undoing the adult consequences of destructive childhood experiences, and the relationship of marital variables to the onset and course of depressive disorders. Clinical experience and research findings suggest that clinicians treating couples and families may be helpful by using techniques designed to both increase the intensity of affective bonds and repair the inevitable disruptions of those bonds. It is also noted that recent psychophysiologic studies suggest that derivatives of intense affective bonds and their disruptions, in the form of confiding and conflict, may influence both vascular reactivity and cellular immune competence. These studies suggest that "for better or worse" may have physiologic as well as psychological implications.

Conservation of T cell receptor conformation in epidermal gammadelta cells with disrupted primary Vgamma gene usage

A feature that distinguishes gammadelta T cell subsets from most alphabeta T cells and B cells is the association of expression of single T cell receptor (TCR) gamma and delta variable (V) region gene segments with specific anatomic sites. Mice lacking the TCR Vgamma5 chain normally expressed by most dendritic epidermal T cells were shown to retain a conformational determinant (idiotype) ordinarily expressed exclusively by such Vgamma5+ cells. Conservation by shuffled gammadelta TCR chains of an idiotype associated with a specific anatomic site indicates that for TCRgammadelta, as for immunoglobulin, conformation is associated to a greater extent with the function or development of lymphocyte repertoires than is the use of particular gene segments.

Pearls in the management of submacular hematoma

Subretinal hemorrhage (SRH), complicated by choroidal neovascularization such as age-related macular degeneration, often reduces central vision in middle-aged patients. Although the visual results of SRH removal by surgery seem to have improved recently, the efficacy has not yet been confirmed in a prospective, controlled fashion. Therefore, it cannot be stated with certainty that surgery for SRH is more beneficial than the natural course of the disease. However, we believe surgery is beneficial in selected patients. Herein, we describe our technique for the surgical removal of SRH. The development of safer, more effective techniques should further improve patient outcomes.

Extrusion of an anterior chamber intraocular lens complicated by Haemophilus endophthalmitis

PURPOSE

To describe a case of late postoperative endophthalmitis in a patient who had undergone anterior chamber intraocular lens implantation 6 years previously.

METHOD

Onset, course, and outcome of the patient's eye disease are presented.

RESULTS

The patient was initially examined with erosion of the eyewall, extrusion of the lens haptic, and endophthalmitis. Intraocular cultures disclosed the pathogenic organism to be Haemophilus influenzae.

CONCLUSION

Anterior chamber intraocular lens haptic extrusion can have grave consequences, including endophthalmitis and severe visual loss.

Subretinal fluid drainage with the erbium:YAG laser in rabbit eyes

BACKGROUND AND OBJECTIVE

To evaluate the efficacy and safety of the erbium:yttrium-aluminum-garnet (Er:YAG) laser for choroidotomy as a means of performing external drainage of subretinal fluid with less risk of choroidal bleeding.

MATERIALS AND METHODS

The authors tested this application in a rabbit model of retinal detachment by evaluating the effects of Er:YAG laser energy on the bare choroid at various energy settings (1, 2, 3, or 5 mJ/pulse) and repetition rates (2, 4, 10, or 30 Hz).

RESULTS

Although the choroid was not perforated at low energy and frequency settings, choroidotomy was successfully achieved as energy and repetition rate were increased. Through higher energy levels per pulse and higher repetition rates, choroidotomy was achieved at lower total energy levels. No retinal damage was detected after laser choroidotomy. Choroidal bleeding was noted in 2 of 97 eyes; however, no subretinal hemorrhage occurred.

CONCLUSION

These results indicate that the Er:YAG laser may be a clinically useful tool for retinal reattachment surgery.

The double-mirror gonioscopic lens for surgery of the anterior chamber angle

Intraoperative examination of the anterior chamber angle is necessary during several glaucoma procedures, including goniosynechialysis and goniotomy. Many of the available lenses for this purpose are difficult to use because they require oblique illumination and their size interferes with surgical manipulations at the limbus. We have developed a double-mirror gonioscopic lens that uses direct illumination; provides an upright image of angle structures; and has a small diameter, allowing simultaneous access to the entire limbal region. We compared our lens with the Posner goniomirror (Ocular Instruments, Bellvue, Wash) and found that it provides an equal view of angle structures. The double-mirror gonioscopic lens facilitates the intraoperative visualization of the anterior chamber angle and should allow surgeons who treat glaucoma to more accurately and safely perform angle-related procedures.

Diamond-dusted silicone cannula for epiretinal membrane separation during vitreous surgery

PURPOSE

To report a diamond-dusted silicone cannula as a tool for membrane separation during vitreous surgery.

METHODS

A diamond-dusted silicone cannula was fashioned from flexible silicone tubing with a beveled tip and coated with diamond fragments for use during vitreous surgery.

RESULTS

The instrument was used successfully in seven eyes with idiopathic macular hole and was found to be particularly useful for removing residual vitreous cortex and epiretinal membranes from around the hole. It was also effective in removing "immature membranes" in three eyes with proliferative vitreoretinopathy.

CONCLUSION

The diamond-dusted silicone cannula is a useful tool for removing thin epiretinal membranes and vitreous cortex that may be difficult or nearly impossible to remove safely using other techniques.

A Holistic Model for Moving Toward Excellence in Chaotic Times

BACKGROUND

Staff development experts in a tertiary-care hospital were searching for a holistic approach to facilitating improved outcomes.

METHOD

Staff development experts, clinical nurse specialists, and clinical managers developed a model that provides a framework for educators to integrate their energies with those of other leaders in order to create a holistic approach to the goal of achieving excellence.

RESULTS

The model that is proposed links strategies for change with outcome evaluation.

CONCLUSIONS

The model provides a conceptual lens that helps nurse leaders focus on organizational assessment, strategies to improve the work environment, and the evaluation of outcomes. The model is useful for guiding practice as well as research.

An applicator-shaped scleral depressor for vitreoretinal surgery

This article describes an instrument that combines a standard T-shaped scleral depressor at one end with a cotton applicator-shaped depressor at the other end. The applicator-shaped depressor has a matted surface to prevent slippage. This simple instrument has several advantages over depressors now available for intraoperative use.

Accessibility of and client satisfaction with dental services in Melbourne

Public dental clinics play an important role in delivering dental services to Australian adults on low incomes. Our objective was to compare the accessibility of and client satisfaction with the two main types of public dental service providers in Victoria and with private practice services. Clients attending the Royal Dental Hospital of Melbourne, Northcote Community Health Centre and private practices in Melbourne were surveyed. The hospital's clients faced the greatest ecological and organisational obstacles, while private clients faced the greatest financial and desirability obstacles. Community centre clients faced fewer ecological and organisational obstacles than hospital clients, with the exception of long waiting times. Private practice clients were more satisfied overall, and had better continuity of care. Private practice clients were more satisfied with access, availability and convenience than community centre clients, who in turn were more satisfied than hospital clients. There was no distinction between private practice and hospital clients on satisfaction with 'pain and treatment', but community centre clients were less satisfied. There was no significant difference between client group evaluations of interaction with the dentist. Regardless of the effects of the Commonwealth Dental Health Program, distinctions between various service types and public clinic types are likely to remain, because of their different settings. The contrast between a central hospital and a community health centre, in terms of the ecological and organisational obstacles to care, points to the advantages of putting dental services close to the communities they serve.

Secondary vitrectomy for the treatment of macular holes occurring after vitrectomy

Tangential foveal traction by the posterior vitreous cortex is regarded as the main cause of full-thickness macular holes. This report documents two cases of full-thickness macular holes that developed after vitrectomy for other diseases in the apparent absence of the cortical vitreous traction. Autologous serum with pars plana vitrectomy was used to treat these cases. Anatomic closure of the holes was achieved. Macular holes developing after vitrectomy may have an etiology other than tangential vitreous traction, and secondary vitrectomy is useful in treating such holes.

Insulin-like growth factor receptor cooperates with integrin alpha v beta 5 to promote tumor cell dissemination in vivo

Tumor cell interactions with adhesion proteins and growth factors likely contribute to the metastatic cascade. Evidence is provided that insulin or insulin-like growth factor-mediated signals cooperate with the commonly expressed integrin alpha v beta 5 to promote spontaneous pulmonary metastasis of multiple tumor cell types in both the chick embryo and severe combined immune deficiency mouse/human chimeric models. Expression of alpha v beta 5 in tumor cells promoted their adhesion to vitronectin in vitro. However, cell motility required cytokine stimulation, which caused redistribution of alpha-actinin to membrane-adhesive sites containing alpha v beta 5. Significantly, ligation of alpha v beta 5 and cytokine receptors were both required for spontaneous pulmonary metastasis of multiple tumor types even though it was not necessary for primary tumor growth. Thus, tumor cell metastasis can be regulated by a functional cooperation between cytokine signaling events and the adhesion receptor alpha v beta 5 in a manner independent of tumor cell growth. These findings provide evidence that integrin ligation, in conjunction with cytokine activation, plays an important role in the dissemination of malignant tumor cells.

Exotropia secondary to vitreous hemorrhage

BACKGROUND

Diplopia after cataract surgery has been reported by several authors, but diplopia after recovery from vitreous hemorrhage (VH) has not been described.

METHODS

We examined eight patients with manifest exotropia and binocular diplopia after recovery from dense VH by vitreous surgery. VH was bilateral in three patients and unilateral in five, and lasted for an average of 7.7 years.

RESULTS

Visual acuity before vitrectomy ranged from 20/200 to light perception; that after vitrectomy ranged from 20/20 to 20/60. Exotropia was present in all patients after vitrectomy. Additionally, seven out of eight patients had vertical strabismus with an average deviation of 6 prism diopters (delta). Fusion was confirmed in four patients with an average amplitude of 13 delta. Four patients underwent horizontal strabismus surgery. Fusion was present in two before strabismus surgery and in all four after surgery; however, unstable diplopia persisted in three of the four after surgery.

CONCLUSION

Diplopia after vitrectomy for longstanding VH may occur due to fusion impairment comparable to that occasionally seen after surgery for traumatic cataract.

Ophthalmomyiasis interna posterior. Report of a case with optic atrophy

PURPOSE

The prognosis for patients with ophthalmomyiasis Interna posterior is variable. In many patients the larva remains in the eye for years without inducing inflammation or loss of vision. Sometimes, however, the migrating larva involves the macula and optic nerve and results in permanent visual loss or even blindness.

METHODS

Our patient presented with sudden painless loss of vision in the right eye that was caused by ophthalmomyiasis interna posterior. Hemorrhage of the optic nerve head suggested that the fly larva had entered the vitreous cavity from the optic nerve head. Subretinal tracts were sequelae of the subretinal migration of the organism. Sequential photographs documented the fly larva migration into the optic nerve head head from the vitreous cavity. The organism was removed by pars plana vitrectomy and retinectomy.

RESULTS

In spite of the successful removal of the first stage fly larva, the visual acuity remained poor because of optic nerve atrophy.

CONCLUSION

We suggest early removal of fly larvae to prevent damage and visual loss in cases of ocular myiasis interna posterior.

Retinal detachment after branch retinal vein occlusion: influence of the type of break on the outcome of vitreous surgery

BACKGROUND

Branch retinal vein occlusion (BRVO) is occasionally complicated by two types of retinal breaks (retinal holes without vitreous traction or retinal traction tears) that may lead to a rhegmatogenous retinal detachment (RRD). The authors describe surgical results of vitrectomy for RRD after BRVO and investigate whether there is any difference between clinical features or surgical results from eyes with the two types of retinal breaks.

PATIENTS AND METHODS

The authors retrospectively studied 25 patients (25 eyes) who underwent vitrectomy for RRD after BRVO. Twelve of 25 eyes (48%) had a detachment secondary to one or more retinal holes (group I), and 13 of the eyes (52%) had one or more retinal tears (group II).

RESULTS

Seventeen of the eyes (68%) achieved total retinal reattachment after the initial surgery; 22 (88%) did so by the time of final examination. Patients with retinal holes achieved more favorable final vision than those with retinal tears (P = 0.0391). A higher rate of preoperative macular detachment (P = 0.0112) and a higher rate of recurrent retinal detachment after initial vitrectomy (P = 0.0302) were the factors associated with the reduced final visual acuity in patients with retinal tears. The increased rate of recurrent retinal detachment in patients with retinal tears was associated with a higher rate of existing preretinal neovascular membranes (P = 0.0112) and a trend toward an increased incidence of intraoperative iatrogenic retinal breaks.

CONCLUSION

Among patients who undergo vitrectomy for RRD after BRVO, better surgical results are expected in eyes with retinal holes without vitreous traction than in those with retinal traction tears. This difference is thought to be due to the difference in vitreoretinal anatomy between eyes with the two types of retinal breaks.

Integrin regulation of c-Abl tyrosine kinase activity and cytoplasmic-nuclear transport

The product of the c-abl protooncogene is a nonreceptor tyrosine kinase found in both the cytoplasm and the nucleus. We report herein that cell adhesion regulates the kinase activity and subcellular localization of c-Abl. When fibroblastic cells are detached from the extracellular matrix, kinase activity of both cytoplasmic and nuclear c-Abl decreases, but there is no detectable alteration in the subcellular distribution. Upon adhesion to the extracellular matrix protein fibronectin, a transient recruitment of a subset of c-Abl to early focal contacts is observed coincident with the export of c-Abl from the nucleus to the cytoplasm. The cytoplasmic pool of c-Abl is reactivated within 5 min of adhesion, but the nuclear c-Abl is reactivated after 30 min, correlating closely with its return to the nucleus and suggesting that the active nuclear c-Abl originates in the cytoplasm. In quiescent cells where nuclear c-Abl activity is low, the cytoplasmic c-Abl is similarly regulated by adhesion but the nuclear c-Abl is not activated upon cell attachment. These results show that c-Abl activation requires cell adhesion and that this tyrosine kinase can transmit integrin signals to the nucleus where it may function to integrate adhesion and cell cycle signals.