A multifunctional soft robotic shape display with high-speed actuation, sensing, and control

Shape displays which actively manipulate surface geometry are an expanding robotics domain with applications to haptics, manufacturing, aerodynamics, and more. However, existing displays often lack high-fidelity shape morphing, high-speed deformation, and embedded state sensing, limiting their potential uses. Here, we demonstrate a multifunctional soft shape display driven by a 10 × 10 array of scalable cellular units which combine high-speed electrohydraulic soft actuation, magnetic-based sensing, and control circuitry. We report high-performance reversible shape morphing up to 50 Hz, sensing of surface deformations with 0.1 mm sensitivity and external forces with 50 mN sensitivity in each cell, which we demonstrate across a multitude of applications including user interaction, image display, sensing of object mass, and dynamic manipulation of solids and liquids. This work showcases the rich multifunctionality and high-performance capabilities that arise from tightly-integrating large numbers of electrohydraulic actuators, soft sensors, and controllers at a previously undemonstrated scale in soft robotics.

Cytoarchitecture of the medial nucleus of trapezoid body of three neotropical species of bats (Noctilio leporinus, Phyllostomus hastatus, and Carollia perspicillata) with different foraging behavior

The present study was taken to test the hypothesis that the medial nucleus of the trapezoid body (MNTB) of echolocating neotropical bats with different foraging behavior will exhibit morphological variations in relative size, degree of complexity and spatial distribution. The brains were collected from six male adult bats of each species: Noctilio leporinus (fish-eating), Phyllostomus hastatus (carnivorous/ omnivorous) and Carollia perspicillata (fruit-eating) and were double-embedded and transverse serial sections were cut and stained with cresyl fast violet. The results showed that the MNTB is well developed in all the bats in general and the mean length of the MNTB was 1160 ± 124 µm in N. leporinus, 400 ± 59 µm in P. hastatus and 320 ± 25µm in C. perspicillata. The body and brain weight do not reflect proportionately on the size of the MNTB in the present study. The hearing frequency spectrum did not covary with the size of the MNTB among the bats studied. The MNTB is clearly demarcated from the ventral nucleus of the trapezoid body (VNTB) only in P. hastatus. The MNTB comprised mainly three types of cells in all three bats: dense-staining multipolar cells (12.5 µm and 25.0 µm diameter); light-staining multipolar cells measuring (12.5 µm and 25.0 µm diameter) and light-staining round cells (5.0 µm diameter). The large sized MNTB was observed in N. leporinus, which suggests that it relies heavily on echolocation whereas P. hastatus and C. perspicillata use echolocation as well but also rely on hearing, smell and vision.

AN ASSOCIATION BETWEEN STELLATE NONHEREDITARY IDIOPATHIC FOVEOMACULAR RETINOSCHISIS, PERIPHERAL RETINOSCHISIS, AND POSTERIOR HYALOID ATTACHMENT

PURPOSE

Stellate nonhereditary idiopathic foveomacular retinoschisis is a disorder characterized by splitting of the retina at the macula, without a known underlying mechanical or inherited cause. This study investigates demographic, anatomical, and functional characteristics of subjects with stellate nonhereditary idiopathic foveomacular retinoschisis, to explore potential underlying mechanisms.

METHODS

In this single-site, retrospective, and cross-sectional, observational study, data were collected from 28 eyes from 24 subjects with stellate nonhereditary idiopathic foveomacular retinoschisis. Descriptive statistics were reported, based on the observed anatomico-functional features.

RESULTS

The visual acuity remained stable (median 20/20) in all subjects over a median follow-up of 17 months. All cases demonstrated foveomacular retinoschisis within Henle's fiber layer, at the junction of the outer plexiform and outer nuclear layers. This schisis cavity extended beyond the limits of the macular OCT temporally in all eyes. In most affected eyes, there were documented features of peripheral retinoschisis and broad attachment of the posterior hyaloid at the macula. Functional testing in a cross-sectional subset demonstrated normal retinal sensitivity centrally but an absolute scotoma peripherally.

CONCLUSION

Stellate nonhereditary idiopathic foveomacular retinoschisis seems to be associated with peripheral retinoschisis and anomalous or incomplete posterior hyaloid detachment. Despite chronic manifestation, this does not significantly affect central visual function but can manifest with profound loss of peripheral visual function.

A rare report on 18-month survival of a dog born with multiple anomalies including atresia ani

Long term survival of animals with major congenital anomalies is very rare. This report documents the 18-month survival of a dog with multiple anomalies including atresia ani. An 18-month-old black Cocker Spaniel bitch was presented for evaluation of prolapsed glands of the third eyelid involving both the eyes. Clinical examination revealed a single perineal opening, fecal matter in the vestibule, distended abdomen, hypoplastic vulva, and the absence of a tail without any neurological deficits. Abdominal contrast radiography revealed a distended colon with fecal stasis, rectovestibular fistula, termination of the rectum as a blind pouch, lumbar scoliosis due to block vertebrae, and the presence of only two hypoplastic coccygeal vertebrae. The case was diagnosed as atresia ani type II with rectovestibular fistula, hypoplastic vulva, lumbar scoliosis, and anury, in the global context of a caudal regression syndrome. The wide aperture fistula, connected to the vestibule, undamaged spinal cord and sacrum without any neurological deficits were the favorable prognostic factors that maintained continence and allowed the dog to survive to adult life with these anomalies. Thus, an appropriate bowel management program and specialty care can improve the quality of life and longevity of this animal.

Cytoarchitecture of the superior olivary complex of three neotropical species of bats (Noctilio leporinus, Phyllostomus hastatus and Carollia perspicillata) with different foraging behavior

The understanding of the echolocation by studying different auditory nuclei of echolocating bats can be an important link in elucidating questions arising in relation to their foraging behavior. The superior olivary complex (SOC) is the primary center for processing the binaural cues used in sound localization since echo locating bats rely on acoustic cues to navigate and capture prey while in flight. The present study was taken to test the hypothesis that the SOC of echolocating neotropical bats with different foraging behavior will exhibit morphological variations in relative size, degree of complexity and spatial distribution. The brains were collected from six male adult bats of each species: Noctilio leporinus (fish eating), Phyllostomus hastatus (carnivorous/omnivorous) and Carollia perspicillata (fruit eating). They were double-embedded and transverse serial sections were cut and stained with cresyl fast violet. The SOC measured as 640 ± 70 µm in the N. leporinus bat, 480 ± 50 µm in the P. hastatus and 240 ± 30 µm in the C. perspicillata bat. The principal nuclei of the SOC of in all three bats were the LSO, MSO and MNTB. The MSO and LSO were very well developed in N. leporinus bats. The MSO of N. leporinus bat subdivided into DMSO and VMSO. The main cell type of cells present in MSO and LSO are dark staining multipolar cells in all the bats studied. The well-developed MSO and LSO of N. leporinus bats indicate that these bats are highly sensitive to low frequency sounds and interaural intensity differences, which help these bats to forage over water by using various types of echolocation signals. The average size of SOC in P. hastatus and C. perspicillata bats can be attributed to the fact that these bats use vision and smell along with echolocation to forage the food.

Excited-state electronic structure of molecules using many-body Green's functions: Quasiparticles and electron-hole excitations with VOTCA-XTP

We present the open-source VOTCA-XTP software for the calculation of the excited-state electronic structure of molecules using many-body Green's function theory in the GW approximation with the Bethe-Salpeter equation (BSE). This work provides a summary of the underlying theory and discusses the details of its implementation based on Gaussian orbitals, including resolution-of-identity techniques and different approaches to the frequency integration of the self-energy or acceleration by offloading compute-intensive matrix operations using graphics processing units in a hybrid OpenMP/Cuda scheme. A distinctive feature of VOTCA-XTP is the capability to couple the calculation of electronic excitations to a classical polarizable environment on an atomistic level in a coupled quantum- and molecular-mechanics (QM/MM) scheme, where a complex morphology can be imported from Molecular Dynamics simulations. The capabilities and limitations of the GW-BSE implementation are illustrated with two examples. First, we study the dependence of optically active electron-hole excitations in a series of diketopyrrolopyrrole-based oligomers on molecular-architecture modifications and the number of repeat units. Second, we use the GW-BSE/MM setup to investigate the effect of polarization on localized and intermolecular charge-transfer excited states in morphologies of low-donor content rubrene-fullerene mixtures. These showcases demonstrate that our implementation currently allows us to treat systems with up to 2500 basis functions on regular shared-memory workstations, providing accurate descriptions of quasiparticle and coupled electron-hole excited states of various characters on an equal footing.

Studies on clinical anatomy of the maxillofacial and mandibular regions of the Madras Red sheep (Ovis aries) in India

BACKGROUND

The present study aimed to study the clinical anatomy of the maxillofacial and mandibular regions of the Madras Red sheep through the morphometric analysis of some clinically important parameters pertaining to the regional anaesthesia.

MATERIALS AND METHODS

The study was conducted in 20 male and 20 female adult Madras Red sheep around 20-25 kg body weight. Eleven parameters re- lated to the clinical regional anaesthesia of the maxillofacial and the mandibular regions were recorded.

RESULTS

The distance between the facial tuberosity to the infraorbital canal was 2.25 ± 0.14 cm in males and 2.14 ± 0.15 cm in females. The distance from the infraorbital canal to the root of the alveolar tooth was 1.73 ± 0.28 cm in males and 1.73 ± 0.13 cm in females. The length and height of the mandibles were 15.37 ± 0.56 cm, 9.00 ± 0.24 cm and in males 14.53 ± 0.24 cm, 9.68 ± 0.16 cm in females, respectively. The maximum height of the mandible to the coro- noid process, width or height of the mandibular foramen and the distance from the condyloid process to the base of the mandible were recorded as 9.0 ± 24, 0.82 ± 0.05, 6.68 ± 0.19 cm in males and 9.68 ± 0.16, 0.83 ± 0.04, 6.25 ± ± 0.28 cm in females, respectively.

CONCLUSIONS

The present study revealed that most of the parameters showed statistically significant difference between the sexes i.e. the males had higher values. However, from the practical point of view, these differences were meagre. The results were discussed with regard to their clinical applications in various regional anaesthesia performed in maxillofacial and mandibular regions of the Madras Red sheep.

Adjustable versus non-adjustable sutures for strabismus

BACKGROUND

Strabismus, or squint, can be defined as a deviation from perfect ocular alignment and can be classified in many ways according to its aetiology and presentation. Treatment can be broadly divided into medical and surgical options, with a variety of surgical techniques being available, including the use of adjustable or non-adjustable sutures for the extraocular muscles. There exists an uncertainty as to which of these techniques produces a better surgical outcome, and an opinion that the adjustable suture technique may be of greater benefit in certain situations.

OBJECTIVES

To determine if either an adjustable suture or non-adjustable suture technique is associated with a more accurate long-term ocular alignment and to identify specific situations in which it would be of benefit to use a particular method.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2017, Issue 5); Ovid MEDLINE; Ovid Embase; LILACS; the ISRCTN registry; ClinicalTrials.gov and the ICTRP. The date of the search was 13 June 2017. We contacted experts in the field for further information.

SELECTION CRITERIA

We included only randomised controlled trials (RCTs) comparing adjustable to non-adjustable sutures for strabismus surgery.

DATA COLLECTION AND ANALYSIS

We used standard procedures recommended by Cochrane. Two review authors independently screened search results and extracted data. We graded the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We identified one RCT comparing adjustable and non-adjustable sutures in primary horizontal strabismus surgeries in 60 children aged less than 12 years in Egypt. The study was not masked and we judged it at high risk of detection bias. Ocular alignment was defined as orthophoria or a horizontal tropia of 8 prism dioptres (PD) or less at near and far distances. At six months, there may be a small increased chance of ocular alignment with adjustable sutures compared with non-adjustable sutures clinically, however, the confidence intervals (CIs) were wide and were compatible with an increased chance of ocular alignment in the non-adjustable sutures group, so there was no statistical difference (risk ratio (RR) 1.18, 95% CI 0.91 to 1.53). We judged this to be low-certainty evidence, downgrading for imprecision and risk of bias. At six months, 730 per 1000 children in the non-adjustable sutures group had ocular alignment. The study authors reported that there were no complications during surgery. The trials did not assess patient satisfaction and resource use and costs.

AUTHORS' CONCLUSIONS

We could reach no reliable conclusions regarding which technique (adjustable or non-adjustable sutures) produced a more accurate long-term ocular alignment following strabismus surgery or in which specific situations one technique is of greater benefit than the other, given the low-certainty and chance with just the one study. More high-quality RCTs are needed to obtain clinically valid results and to clarify these issues. Such trials should ideally 1. recruit participants with any type of strabismus or specify the subgroup of participants to be studied, for example, thyroid, paralytic, non-paralytic, paediatric; 2. randomise all consenting participants to have either adjustable or non-adjustable surgery prospectively; 3. have at least six months of follow-up data; and 4. include reoperation rates as an outcome measure.

Characterizing CD137 upregulation on NK cells in patients receiving monoclonal antibody therapy

Background

In the era of personalized cancer medicine, identifying techniques for effectively matching patients to efficacious treatments is a critical step in the treatment process. The advent of anti-cancer immunotherapies necessitates novel approaches to biomarker identification beyond traditional genomic profiling. One promising approach is incorporation of nomograms into treatment decisions. Nomograms are prediction tools, based on statistical modeling, designed to predict treatment outcomes. As a first step toward developing a nomogram, we conducted analyses to predict CD137 expression of natural killer cells after monoclonal antibody (mAb) treatment.

Patients and methods

Patient, tumor and immune characteristics were collected from 199 patients with breast cancer (N = 62), head/neck cancers (N = 46) and non-Hodgkin's lymphoma (NHL) (N = 91), who were receiving mAb therapy as part of clinical trials. The difference in CD137 expression before and after mAb therapy was assessed by flow cytometry. To evaluate those who respond to mAb therapy via increased CD137 expression, we applied classification and regression trees (CART), multivariable lasso regression tools and Random Forest.

Results

The CD137 expression was significantly different for each cancer type [mean (SD): Breast: 6.6 (6.5); Head/Neck: 11.0 (7.0); NHL: 7.5 (7.1), P < 0.0001]. For breast cancer and NHL, FcR polymorphism and baseline CD137 expression were significant predictors of increased CD137 expression; for head/neck cancer, FcR polymorphism and age were significant predictors of increased expression.

Conclusions

Our preliminary results suggest that FcR polymorphism, pre-treatment CD137 expression and age are significant predictors of CD137 upregulation in patients. This study demonstrates that the development of a nomogram for therapy response is feasible. Further work validating our models in an independent cohort will provide the next steps in developing a nomogram that may be used to individualize this therapeutic approach for patients (NCT01114256).

Spectral sensitivity measurements reveal partial success in restoring missing rod function with gene therapy

Restored rod visual function after gene therapy can be established unequivocally by demonstrating that, after dark adaptation, spectral sensitivity has the shape characteristic of rods and that this shape collapses to a cone-like shape before rods have recovered after an intense bleach. We used these tests to assess retinal function in eight young adults and children with early-onset severe retinal dystrophy from Phase II of a clinical gene-therapy trial for RPE65 deficiency that involved the subretinal delivery of a recombinant adeno-associated viral vector carrying RPE65. We found substantial improvements in rod sensitivity in two participants: dark-adapted spectral sensitivity was rod-like after treatment and was cone-like before rods had recovered after a bleach. After 40 min of dark adaptation, one participant showed up to 1,000-fold sensitivity improvements 4 months after treatment and the second up to 100-fold improvements 6 months after treatment. The dark-adapted spectral sensitivities of the other six participants remained cone-like and showed little improvement in sensitivity.

Obesity is independently associated with infection in hospitalised patients with end-stage liver disease

BACKGROUND

Infection is the most common cause of mortality in end-stage liver disease (ESLD). The impact of obesity on infection risk in ESLD is not established.

AIM

To characterise the impact of obesity on infection risk in ESLD.

METHODS

We evaluated the association between infection and obesity in patients with ESLD. Patients grouped as non-obese, obesity class I-II and obesity class III were studied using the Nationwide Inpatient Sample. Validated diagnostic code based algorithms were utilised to determine weight category and infections, including bacteraemia, skin/soft tissue infection, urinary tract infection (UTI), pneumonia/respiratory infection, Clostridium difficile infection (CDI) and spontaneous bacterial peritonitis (SBP). Risk factors for infection and mortality were assessed using multivariable logistic regression analysis.

RESULTS

Of 115 465 patients identified, 100 957 (87.5%) were non-obese and 14 508 (12.5%) were obese, with 9489 (8.2%) as obesity class I-II and 5019 (4.3%) as obesity class III. 37 117 patients (32.1%) had an infection diagnosis. Infection was most prevalent among obesity class III (44.0%), followed by obesity class I-II (38.9%) and then non-obese (31.9%). In multivariable modelling, class III obesity (OR = 1.41; 95% CI 1.32-1.51; P < 0.001), and class I-II obesity (OR = 1.08; 95% CI 1.01-1.15; P = 0.026) were associated with infection. Compared to non-obese patients, obese individuals had greater prevalence of bacteraemia, UTI, and skin/soft tissue infection as compared to non-obese patients.

CONCLUSIONS

Obesity is newly identified to be independently associated with infection in end-stage liver disease. The distribution of infection sites varies based on weight category.

Incidence and risk factors of deep vein thrombosis after liver transplantation

BACKGROUND

Deep venous thrombosis (DVT) occurs in 0.1% of persons per year, affecting 15%-40% of general surgical procedures without prophylaxis. Thromboembolic prophylaxis is not commonly used after orthotopic liver transplantation (LT) owing to the risks of bleeding and coagulopathy. Cirrhosis and the association with the coagulation cascade, before and after transplantation, are not well understood. The purpose of this study was to determine the incidence of DVT and its risk factors after LT.

METHODS

We retrospectively reviewed LTs performed at our center from 2005 to 2012. We identified patients with Doppler examinations showing DVT after LT, platelet count, and international normalized ratio (INR) at time of DVT, associated symptoms, DVT prophylaxis, and perioperative risk factors. We determined the incidence of DVT, the odds ratio of each preoperative risk factor, the difference in platelet count and INR between those with and without a DVT, and the weighted risk of each factor in the development of DVT with the use of logistic regression modeling.

RESULTS

Of 314 patients, the incidence of DVT was 8.6% (27/314). Between those with and without DVT there was no significant difference in age, sex, platelet count, INR, infection, hepatocellular cancer, use of venous bypass, and prior surgery. There was a significant difference in mobility, 67% vs 20% (P < .0001), and the use of factor VII, 11% vs 2% (P < .05). The estimated risk for of developing DVT for patients with neither of these factors was 4%; with factor VII the risk rose to 17%; with mobility difficulty the risk rose to 23%; and with both the risk was 62%. In our entire population, there were no cases of pulmonary embolism.

CONCLUSIONS

The risk of developing a DVT after LT is ≥9% even with mechanical DVT prophylaxis. Consideration should be given to using both mechanical and chemical prophylaxis after LT.

Long-term effect of gene therapy on Leber's congenital amaurosis

BACKGROUND

Mutations in RPE65 cause Leber's congenital amaurosis, a progressive retinal degenerative disease that severely impairs sight in children. Gene therapy can result in modest improvements in night vision, but knowledge of its efficacy in humans is limited.

METHODS

We performed a phase 1-2 open-label trial involving 12 participants to evaluate the safety and efficacy of gene therapy with a recombinant adeno-associated virus 2/2 (rAAV2/2) vector carrying the RPE65 complementary DNA, and measured visual function over the course of 3 years. Four participants were administered a lower dose of the vector, and 8 were administered a higher dose. In a parallel study in dogs, we investigated the relationship among vector dose, visual function, and electroretinography (ERG) findings.

RESULTS

Improvements in retinal sensitivity were evident, to varying extents, in six participants for up to 3 years, peaking at 6 to 12 months after treatment and then declining. No associated improvement in retinal function was detected by means of ERG. Three participants had intraocular inflammation, and two had clinically significant deterioration of visual acuity. The reduction in central retinal thickness varied among participants. In dogs, RPE65 gene therapy with the same vector at lower doses improved vision-guided behavior, but only higher doses resulted in improvements in retinal function that were detectable with the use of ERG.

CONCLUSIONS

Gene therapy with rAAV2/2 RPE65 vector improved retinal sensitivity, albeit modestly and temporarily. Comparison with the results obtained in the dog model indicates that there is a species difference in the amount of RPE65 required to drive the visual cycle and that the demand for RPE65 in affected persons was not met to the extent required for a durable, robust effect. (Funded by the National Institute for Health Research and others; ClinicalTrials.gov number, NCT00643747.).

Spontaneous coronary artery thrombosis in the setting of active lupus mesenteric vasculitis

A 33-year-old male with systemic lupus erythematosus (SLE) presented with acute abdominal pain and was found to have lupus mesenteric vasculitis on imaging and during exploratory laparotomy. Post laparotomy he continued to have persistent nausea and dyspepsia and an electrocardiogram showed evidence of an inferior ST elevation myocardial infarction (STEMI). Emergency cardiac catheterization showed evidence of thrombotic right coronary artery occlusion. His coronaries were otherwise normal with no evidence of underlying coronary artery disease. Extensive workup with trans-esophageal echo, serologies for antiphospholipid antibody syndrome (APS) and bubble study was negative. This effectively ruled out Libman–Sacks endocarditis, APS-induced arterial thrombus and paradoxical emboli as potential causes of his STEMI. By exclusion of other causes, the etiology of his STEMI was felt to be secondary to in-situ coronary artery thrombosis in the setting of active SLE. To the best of our knowledge, this is the first report of a patient with SLE presenting with both lupus mesenteric vasculitis and in-situ coronary arterial thrombosis in the absence of APS.

Genotype-dependent variability in residual cone structure in achromatopsia: toward developing metrics for assessing cone health

PURPOSE

Gene therapy trials for inherited photoreceptor disorders are planned. Anatomical metrics to select the best candidates and outcomes are needed. Adaptive optics (AO) imaging enables visualization of photoreceptor structure, although analytical tools are lacking. Here we present criteria to assess residual photoreceptor integrity in achromatopsia (ACHM).

METHODS

Two AOSLOs, at the Medical College of Wisconsin and Moorfields Eye Hospital, were used to image the photoreceptor mosaic of 11 subjects with ACHM and 7 age-matched controls. Images were obtained, processed, and montaged using previously described methods. Cone density and reflectivity were quantified to assess residual cone photoreceptor structure.

RESULTS

All subjects with ACHM had reduced numbers of cone photoreceptors, albeit to a variable degree. In addition, the relative cone reflectivity varied greatly. Interestingly, subjects with GNAT2-associated ACHM had the greatest number of residual cones and the reflectivity of those cones was significantly greater than that of the cones in the subjects with CNGA3/CNGB3-associated ACHM.

CONCLUSIONS

We present cone reflectivity as a metric that can be used to characterize cone structure in ACHM. This method may be applicable to subjects with other cone disorders. In ACHM, we hypothesize that cone numerosity (and/or density) combined with cone reflectivity could be used to gauge the therapeutic potential. As gene replacement would not be expected to add cones, reflectivity could be a more powerful AO-metric for monitoring the cellular response to treatment and could provide a more immediate indicator of efficacy than behavioral measures, which may take longer to change.

Nature of the visual loss in observers with Leber's congenital amaurosis caused by specific mutations in RPE65

PURPOSE

To characterize visual losses associated with genetic mutations in the RPE65 gene that cause defects in the RPE-specific isomerase, RPE65. RPE65 is an important component of the retinoid cycle that restores 11-cis-retinal after its photoisomerization to its all-trans form. The defects investigated here cause Leber's congenital amaurosis (LCA2), an autosomal, recessively-inherited, severe, congenital-onset rod-cone dystrophy.

METHODS

Vision was assessed in nine patients and 10 normal controls by measuring: (1) long-wavelength sensitive (L-) cone temporal acuity (critical flicker fusion frequency or cff) as a function of target illuminance, and (2) L-cone temporal contrast sensitivity as a function of temporal frequency at a fixed-target illuminance. Measurements were made by modulating either a 650-nm light superimposed on a 480-nm background or the red phosphor of a color monitor on a background produced by the monitor's blue phosphor.

RESULTS

RPE65-mutant observers have severely reduced cffs with shallower cff versus log illuminance functions that rise with a mean slope of 4.53 Hz per decade of illuminance compared with 8.69 Hz in normal controls. Consistent with the cff differences, RPE65-mutant observers show losses in temporal contrast sensitivity that increase rapidly with temporal frequency.

CONCLUSIONS

All RPE65-mutant observers have consistent and substantial losses in temporal acuity and sensitivity compared with normal observers. The losses can be characterized by the addition of two sluggish filters within the mutant visual pathway, both filters with a time constant of 29.5 ms (i.e., low-pass filters with cut-off frequencies of 5.40 Hz).

A prospective longitudinal study of retinal structure and function in achromatopsia

PURPOSE

To longitudinally characterize retinal structure and function in achromatopsia (ACHM) in preparation for clinical gene therapy trials.

METHODS

Thirty-eight molecularly confirmed ACHM subjects underwent serial assessments, including spectral domain optical coherence tomography (SD-OCT), microperimetry, and fundus autofluorescence (FAF). Foveal structure on SD-OCT was graded and compared for evidence of progression, along with serial measurements of foveal total retinal thickness (FTRT) and outer nuclear layer (ONL) thickness. Fundus autofluorescence patterns were characterized and compared over time.

RESULTS

Mean follow-up was 19.5 months (age range at baseline, 6-52 years). Only 2 (5%) of 37 subjects demonstrated change in serial foveal SD-OCT scans. There was no statistically significant change over time in FTRT (P = 0.83), ONL thickness (P = 0.27), hyporeflective zone diameter (P = 0.42), visual acuity (P = 0.89), contrast sensitivity (P = 0.22), mean retinal sensitivity (P = 0.84), and fixation stability (P = 0.58). Three distinct FAF patterns were observed (n = 30): central increased FAF (n = 4), normal FAF (n = 11), and well-demarcated reduced FAF (n = 15); with the latter group displaying a slow increase in the area of reduced FAF of 0.03 mm(2) over 19.3 months (P = 0.002).

CONCLUSIONS

Previously published cross-sectional studies have described conflicting findings with respect to the age-dependency of progression. This study, which constitutes the largest and longest prospective longitudinal study of ACHM to date, suggests that although ACHM may be progressive, any such progression is slow and subtle in most patients, and does not correlate with age or genotype. We also describe the first serial assessment of FAF, which is highly variable between individuals, even of similar age and genotype.

Retinal structure and function in achromatopsia: implications for gene therapy

PURPOSE

To characterize retinal structure and function in achromatopsia (ACHM) in preparation for clinical trials of gene therapy.

DESIGN

Cross-sectional study.

PARTICIPANTS

Forty subjects with ACHM.

METHODS

All subjects underwent spectral domain optical coherence tomography (SD-OCT), microperimetry, and molecular genetic testing. Foveal structure on SD-OCT was graded into 5 distinct categories: (1) continuous inner segment ellipsoid (ISe), (2) ISe disruption, (3) ISe absence, (4) presence of a hyporeflective zone (HRZ), and (5) outer retinal atrophy including retinal pigment epithelial loss. Foveal and outer nuclear layer (ONL) thickness was measured and presence of hypoplasia determined.

MAIN OUTCOME MEASURES

Photoreceptor appearance on SD-OCT imaging, foveal and ONL thickness, presence of foveal hypoplasia, retinal sensitivity and fixation stability, and association of these parameters with age and genotype.

RESULTS

Forty subjects with a mean age of 24.9 years (range, 6-52 years) were included. Disease-causing variants were found in CNGA3 (n = 18), CNGB3 (n = 15), GNAT2 (n = 4), and PDE6C (n = 1). No variants were found in 2 individuals. In all, 22.5% of subjects had a continuous ISe layer at the fovea, 27.5% had ISe disruption, 20% had an absent ISe layer, 22.5% had an HRZ, and 7.5% had outer retinal atrophy. No significant differences in age (P = 0.77), mean retinal sensitivity (P = 0.21), or fixation stability (P = 0.34) across the 5 SD-OCT categories were evident. No correlation was found between age and foveal thickness (P = 0.84) or between age and foveal ONL thickness (P = 0.12).

CONCLUSIONS

The lack of a clear association of disruption of retinal structure or function in ACHM with age suggests that the window of opportunity for intervention by gene therapy is wider in some individuals than previously indicated. Therefore, the potential benefit for a given subject is likely to be better predicted by specific measurement of photoreceptor structure rather than simply by age. The ability to directly assess cone photoreceptor preservation with SD-OCT and/or adaptive optics imaging is likely to prove invaluable in selecting subjects for future trials and measuring the trials' impact.

Adjustable versus non-adjustable sutures for strabismus

BACKGROUND

Strabismus, or squint, can be defined as a deviation from perfect ocular alignment and can be classified in many ways according to its aetiology and presentation. Treatment can be broadly divided into medical and surgical options, with a variety of surgical techniques being available, including the use of adjustable or non-adjustable sutures for the extraocular muscles. There exists an uncertainty as to which of these techniques produces a better surgical outcome, and also an opinion that the adjustable suture technique may be of greater benefit in certain situations.

OBJECTIVES

To examine whether adjustable or non-adjustable sutures are associated with a more accurate long-term ocular alignment following strabismus surgery and to identify any specific situations in which it would be of benefit to use a particular method.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2012, Issue 12), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE, (January 1950 to January 2013), EMBASE (January 1980 to January 2013), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to January 2013), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (http://clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 17 January 2013. We also contacted experts in the field for further information.

SELECTION CRITERIA

We planned to include only randomised controlled trials (RCTs) comparing adjustable to non-adjustable sutures for strabismus surgery.

DATA COLLECTION AND ANALYSIS

We did not find any studies that met the inclusion criteria for this review.

MAIN RESULTS

We did not find any studies that met the inclusion criteria for this review, therefore none were included for analysis. Results of non-randomised studies that compared these techniques are reported.

AUTHORS' CONCLUSIONS

No reliable conclusions could be reached regarding which technique (adjustable or non-adjustable sutures) produces a more accurate long-term ocular alignment following strabismus surgery or in which specific situations one technique is of greater benefit than the other. High quality RCTs are needed to obtain clinically valid results and to clarify these issues. Such trials should ideally a) recruit participants with any type of strabismus or specify the subgroup of participants to be studied, for example, thyroid, paralytic, non-paralytic, paediatric; b) randomise all consenting participants to have either adjustable or non-adjustable surgery prospectively; c) have at least six months of follow-up data; and d) include re-operation rates as a primary outcome measure.

Intravitreal low molecular weight heparin and 5-Fluorouracil for the prevention of proliferative vitreoretinopathy following retinal reattachment surgery

BACKGROUND

Proliferative vitreoretinopathy (PVR) is a significant cause of failure in retinal reattachment surgery. Various pharmacological agents have shown potential benefit in reducing postoperative PVR risk.

OBJECTIVES

This review aimed to compare the use of intravitreal low molecular weight heparin (LMWH) alone or with 5-Fluorouracil (5-FU) versus placebo, as an adjunct in the prevention of PVR following retinal reattachment surgery.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2012, Issue 9), MEDLINE (January 1950 to October 2012), EMBASE (January 1980 to October 2012), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 15 October 2012.

SELECTION CRITERIA

We only included randomised controlled trials (RCTs) that compared intravitreal LMWH alone or with 5-FU, versus placebo for the prevention of postoperative PVR in patients undergoing primary vitrectomy for rhegmatogenous retinal detachment repair.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. The review authors contacted study authors for additional information.

MAIN RESULTS

We included two RCTs (with a total of 789 participants) comparing LMWH with 5-FU infusion and placebo. However, we did not perform a meta-analysis because of significant heterogeneity between these studies. One study found a significant beneficial effect of LMWH with 5-FU in reducing postoperative PVR compared to placebo (RR: 0.48, 95% confidence interval: 0.25 to 0.92), in 174 patients who were viewed at high-risk of developing postoperative PVR. The other study included 615 unselected cases of rhegmatogenous retinal detachment and could not show a difference between LMWH with 5-FU infusion and placebo in reducing PVR rates (RR:1.45, 95% confidence interval: 0.76 to 2.76).

AUTHORS' CONCLUSIONS

Results from this review indicate that there is inconsistent evidence from two studies on patients at different risk of PVR on the effect of LMWH and 5-FU used during vitrectomy to prevent PVR. Future research should be conducted on high risk patients only, until a benefit is confirmed at least in this patient subgroup.

Retinal dystrophies and gene therapy

Retinal dystrophies are inherited disorders of photoreceptor and retinal pigment epithelial function that may result in severe visual impairment. Advances in molecular genetics have helped identify many of the gene defects responsible, and progress in gene transfer technology has enabled therapeutic strategies to be developed and applied. The first human clinical trials of gene therapy for RPE65 associated retinal dystrophy have shown promising initial results and have helped prepare the way for further trials of gene therapy for inherited retinal disorders. The results of these trials will provide further insight into the safety and efficacy of gene therapy for a range of currently untreatable and debilitating eye disorders.

Intravitreal low molecular weight heparin and 5-Fluorouracil for the prevention of proliferative vitreoretinopathy following retinal reattachment surgery

BACKGROUND

Proliferative vitreoretinopathy (PVR) is a significant cause of failure in retinal reattachment surgery. Various pharmacological agents have shown potential benefit in reducing postoperative PVR risk.

OBJECTIVES

This review aimed to compare the use of intravitreal low molecular weight heparin (LMWH) alone or with 5-Fluorouracil (5-FU) versus placebo, as an adjunct in the prevention of PVR following retinal reattachment surgery.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2010, Issue 5), MEDLINE (January 1950 to May 2010), EMBASE (January 1980 to May 2010), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com) and ClinicalTrials.gov (http://clinicaltrials.gov). There were no language or date restrictions in the search for trials. The electronic databases were last searched on 24 May 2010.

SELECTION CRITERIA

We only included randomised controlled trials (RCTs) that compared intravitreal LMWH alone or with 5-FU, versus placebo for the prevention of postoperative PVR in patients undergoing primary vitrectomy for rhegmatogenous retinal detachment repair.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. The review authors contacted study authors for additional information.

MAIN RESULTS

We included two RCTs (with a total of 789 participants) comparing LMWH with 5-FU infusion and placebo. However, we did not perform a meta-analysis because of significant heterogeneity between these studies. One study found a significant beneficial effect of LMWH with 5-FU in reducing postoperative PVR compared to placebo (RR: 0.48, 95% confidence interval: 0.25 to 0.92), in 174 patients who were viewed at high-risk of developing postoperative PVR. The other study included 615 unselected cases of rhegmatogenous retinal detachment and could not show a difference between LMWH with 5-FU infusion and placebo in reducing PVR rates (RR:1.45, 95% confidence interval: 0.76 to 2.76).

AUTHORS' CONCLUSIONS

Results from this review indicate that there is inconsistent evidence from two studies on patients at different risk of PVR on the effect of LMWH and 5-FU used during vitrectomy to prevent PVR. Future research should be conducted on high risk patients only, until a benefit is confirmed at least in this patient subgroup.

A randomized trial of computer-based reminders and audit and feedback to improve HIV screening in a primary care setting

Despite recommendations for voluntary HIV screening, few medical centres have implemented screening programmes. The objective of the study was to determine whether an intervention with computer-based reminders and feedback would increase screening for HIV in a Department of Veterans Affairs (VA) health-care system. The design of the study was a randomized controlled trial at five primary care clinics at the VA Palo Alto Health Care System. All primary care providers were eligible to participate in the study. The study intervention was computer-based reminders to either assess HIV risk behaviours or to offer HIV testing; feedback on adherence to reminders was provided. The main outcome measure was the difference in HIV testing rates between intervention and control group providers. The control group providers tested 1.0% ( n = 67) and 1.4% ( n = 106) of patients in the preintervention and intervention period, respectively; intervention providers tested 1.8% ( n = 98) and 1.9% ( n = 114), respectively ( P = 0.75). In our random sample of 753 untested patients, 204 (27%) had documented risk behaviours. Providers were more likely to adhere to reminders to test rather than with reminders to perform risk assessment (11% versus 5%, P < 0.01). Sixty-one percent of providers felt that lack of time prevented risk assessment. In conclusion, in primary care clinics in our setting, HIV testing rates were low. Providers were unaware of the high rates of risky behaviour in their patient population and perceived important barriers to testing. Low-intensity clinical reminders and feedback did not increase rates of screening.

Assessment of long term status of sputum positive pulmonary TB patients successfully treated with short course chemotherapy

BACKGROUND

Long term status of pulmonary tuberculosis (PTB) patients treated with short course chemotherapy (SCC) regimens remains unknown.

OBJECTIVE

To assess the clinical, bacteriological, radiological status and health related quality of life (HRQoL) of PTB patients 14-18 years after successful treatment with SCC.

METHODOLOGY

In a cross-sectional study, cured PTB patients treated during 1986-1990 at the Tuberculosis Research Centre (TRC) were investigated for their current health status including pulmonary function tests (PFT). The St Georges respiratory questionnaire (SGRQ) was used to assess the HRQoL.

RESULTS

The mean period after treatment completion for the 363 eligible participants was 16.5 yrs (range 14-18 yrs., 84% coverage); 25 (7%) had been re-treated and 52 (14%) died. Among the investigated, 58 (29%) had persistent respiratory symptoms; 170 (86%) had radiological sequelae but none had active disease. Abnormal PFT was observed in 96 (65%) with predominantly restrictive type of disease in 66 (45%). The SGRQ scores for activity and impact were high implying impairment in HRQoL.

CONCLUSION

Assessment of long term status of cured PTB patients showed an impairment of lung functions and HRQoL highlighting the need to address these issues in the management of TB that may provide added value to patient care.

Hypercoagulation and thrombophilia in liver disease

A complex balance exists between endogenous procoagulants and the anticoagulant system in liver disease patients. Hypercoagulable events occur in cirrhosis patients despite the well-known bleeding diathesis of liver disease. These events may be clinically evident, such as in portal vein thrombosis or pulmonary embolism, but these conditions may also be a silent contributor to certain disease states, such as portopulmonary hypertension or parenchymal extinction with liver atrophy as well as thrombosis of extracorporeal circuits in dialysis or liver assist devices. Moreover, liver disease-related hypercoagulability may contribute to vascular disease in the increasingly common condition of non-alcoholic fatty liver disease. Despite the incidence of these problems, there are few widely accessible and practical laboratory tests to evaluate the risk of a hypercoagulable event in cirrhosis patients. Furthermore, there is little research on the use of commonly accepted anticoagulants in patients with liver disease. This article is a result of an international symposium on coagulation disorders in liver disease and addresses several areas of specific interest in hypercoagulation in liver disease. Critical areas lacking clinical information are highlighted and future areas of research interest are defined with an aim to foster clinical research in this field.

Sputum conversion at the end of intensive phase of Category-1 regimen in the treatment of pulmonary tuberculosis patients with diabetes mellitus or HIV infection: An analysis of risk factors

BACKGROUND & OBJECTIVE

New smear-positive pulmonary tuberculosis (PTB) patients in the Revised National Tuberculosis Control Programme (RNTCP) are treated with a 6-month short-course chemotherapy (SCC) regimen irrespective of co-morbid conditions. We undertook this retrospective analysis to compare sputum conversion rates (smear, culture) at the end of intensive phase (IP) of Category-1 regimen among patients admitted to concurrent controlled clinical trials: pulmonary tuberculosis alone (PTB) or with type 2 diabetes mellitus (DM-TB) or HIV infection (HIV-TB), and to identify the risk factors influencing sputum conversion.

METHODS

In this retrospective analysis sputum conversion rates at the end of intensive phase (IP) in three concurrent studies undertaken among PTB, DM-TB and HIV-TB patients, during 1998 - 2002 at the Tuberculosis Research Centre (TRC), Chennai, were compared. Sputum smears were examined by fluorescent microscopy. HIV infected patients did not receive anti-retroviral treatment (ART). Patients with DM were treated with oral hypoglycaemic drugs or insulin (sc).

RESULTS

The study population included 98, 92 and 88 patients in the PTB, DM-TB and HIV-TB studies. At the end of IP the smear conversion (58, 61, and 62%) and culture conversion (86, 88 and 92%) rates were similar in the three groups respectively. The variables associated with lack of sputum smear or culture conversion were age >45 yr, higher pre-treatment smear and culture grading, and extent of the radiographic involvement.

INTERPRETATION & CONCLUSION

Our findings confirm that the current policy of the control programme to treat all pulmonary TB patients with or with out co-morbid conditions with Category-I regimen appears to be appropriate.

Simple direct drug susceptibility tests on sputum samples for early detection of resistance in tubercle bacilli

BACKGROUND

Direct sensitivity test either by sputum concentrate (DS) or swab method (DSM) set up along with the primary culture would avoid the delay of four or more weeks required for the indirect test. A comparison of these two methods against the standard indirect sensitivity method under routine laboratory conditions is necessary to prove their merit.

METHOD

Smear positive sputum samples were aliquoted and sensitivity tests were set up by both the direct methods as also an indirect test set up from the primary culture of the same sample.

RESULTS

The agreement with the indirect test results for isoniazid (INH) ranged from 97-98% for the DS method and 93-97% for the DSM method. The corresponding figures were 96-98% by the DS and 94-99% by the DSM method for rifampicin (R). The agreement was less satisfactory for ethambutol (Emb).

CONCLUSION

This study showed that direct sensitivity tests such as DS and DSM methods can detect most of the cultures resistant to INH and R (MDR) from the time growth appears on the primary culture, even as early as the second week of setting up the tests.

Management of multi drug resistance tuberculosis in the field: Tuberculosis Research Centre experience

SETTING

Multi-drug TB resistant (resistant to isoniazid and rifampicin) patients identified from a rural and urban area.

OBJECTIVE

To study the feasibility of managing MDR TB patients under field conditions where DOTS programme has been implemented.

METHODS

MDR TB Patients identified among patients treated under DOTS in the rural area and from cases referred by the NGO when MDR TB was suspected form the study population. Culture and drug susceptibility testing were done at Tuberculosis Research Centre (TRC). Treatment regimen was decided on individual basis. After a period of initial hospitalization, treatment was continued in the respective peripheral health facility or with the NGO after identifying a DOT provider in the field. Patients attended TRC at monthly intervals for clinical, sociological and bacteriological evaluations. Drugs for the month were pre-packed and handed over to the respective center.

RESULTS

A total of 66 MDR TB patients (46 from the rural and 20 from the NGO) started on treatment form the study population and among them 20 (30%) were resistant to one or more second line drugs (Eto, Ofx, Km) including a case of "XDR TB". Less than half the patients stayed in the hospital for more than 10 days. The treatment was provided partially under supervision. Providing injection was identified to be a major problem. Response to treatment could be correctly predicted based on the 6-month smear results in 40 of 42 regular patients. Successful treatment outcome was observed only in 37% of cases with a high default of 24%. Adverse reactions necessitating modification of treatment was required only for three patients.

IMPLICATIONS

Despite having reliable DST and drug logistics, the main challenge was to maintain patients on such prolonged treatment by identifying a provider closer to the patient who can also give injection, have social skills and manage of minor adverse reactions.

A retrospective analysis to determine the effect of independent treatment centres on the case mix for microsurgical training

AIM

To determine the effect of Independent Sector Treatment Centres (ISTC) on microsurgical training.

METHODS

A novel scoring protocol for stratification of cases suitable for microsurgical training was devised. This scoring protocol was applied to all patients who underwent cataract surgery on a single consultant dedicated training list between September and November 2004. These patients are representative of patients remaining on the waiting list after ISTC selection, that is, the residual case mix. Patients who underwent cataract surgery on the same consultant list in the same period in 2003 were also analysed when there was no ISTC or other waiting list initiative in operation.

RESULTS

Data was available for 129 patients. Seventy three patients underwent cataract surgery between September and November 2003 and 56 patients underwent cataract surgery in the same period in 2004. Using the devised scoring protocol, the mean score in the 2003 group was 1.08 +/-1.75 (range, 0.0-10.5) and for the 2004 group the mean score was 2.31 +/-2.65 (range, 0.0-4.5). A Mann-Whitney test showed that there was a statistically significant difference between the scores in the two groups (P=0.0009). With Independent Sector Treatment Centre implementation the percentage of cases suitable only for consultants increased fourfold.

CONCLUSION

The decrease in suitable cases for training as shown in this study is likely to have serious consequences on microsurgical training in the UK. We recommend that the results of this study are considered in any current or future plans for ISTC continuation and expansion.