Depletion of COPI in cancer cells: the role of reactive oxygen species in the induction of lipid accumulation, noncanonical lipophagy and apoptosis.

The coatomer protein complex 1 (COPI) is a multisubunit complex that coats intracellular vesicles and is involved in intracellular protein trafficking. Recently we and others found that depletion of COPI complex subunits zeta (COPZ1) and delta (ARCN1) preferentially kills tumor cells relative to normal cells. Here we delineate the specific cellular effects and sequence of events of COPI complex depletion in tumor cells. We find that this depletion leads to the inhibition of mitochondrial oxidative phosphorylation and the elevation of reactive oxygen species (ROS) production, followed by accumulation of lipid droplets (LDs) and autophagy-associated proteins LC3-II and SQSTM1/p62 and, finally, apoptosis of the tumor cells. Inactivation of ROS in COPI-depleted cells with the mitochondrial-specific quencher, mitoquinone mesylate, attenuated apoptosis and markedly decreased both the size and the number of LDs. COPI depletion caused ROS-dependent accumulation of LC3-II and SQSTM1 which colocalizes with LDs. Lack of double-membrane autophagosomes and insensitivity to Atg5 deletion suggested an accumulation of a microlipophagy complex on the surface of LDs induced by depletion of the COPI complex. Our findings suggest a sequence of cellular events triggered by COPI depletion, starting with inhibition of oxidative phosphorylation, followed by ROS activation and accumulation of LDs and apoptosis.

Numerical method for the projected Gross-Pitaevskii equation in an infinite rotating two-dimensional Bose gas.

We present a method for evolving the projected Gross-Pitaevskii equation in an infinite rotating Bose-Einstein condensate, the ground state of which is a vortex lattice. We use quasiperiodic boundary conditions to investigate the behavior of the bulk superfluid in this system, in the absence of boundaries and edge effects. We also give the Landau gauge expression for the phase of a BEC subjected to these boundary conditions. Our spectral representation uses the eigenfunctions of the one-body Hamiltonian as basis functions. Since there is no known exact quadrature rule for these basis functions we approximately implement the projection associated with the energy cutoff, but we show that by choosing a suitably fine spatial grid the resulting error can be made negligible. We show how the convergence of this model is affected by simulation parameters such as the size of the spatial grid and the number of Landau levels. Adding dissipation, we use our method to find the lattice ground state for N vortices. We can then perturb the ground-state, to investigate the melting of the lattice.

Striated myogenesis and peristalsis in the fetal murine esophagus occur without cell migration or interstitial cells of Cajal.

Esophageal striated myogenesis progresses differently from appendicular myogenesis, but the mechanism underlying this process is incompletely understood. Early theories of transdifferentiation of smooth muscle into striated muscle are not supported by transgenic fate-mapping experiments; however, the origin of esophageal striated muscle remains unknown. To better define the process of striated myogenesis, we examined myogenesis in murine fetal cultured esophageal whole-organ explants. Embryonic day 14.5 (E14.5) esophagi maintained a functional contractile phenotype for up to 7 days in culture. Striated myogenesis, as evidenced by myogenin expression, proceeded in a craniocaudal direction along the length of the esophagus. Esophageal length did not change during this process. Complete, but not partial, mechanical disruption of the rostral esophagus inhibited myogenesis distally. Addition of fibroblast growth factor-2 (FGF-2) to the culture media failed to inhibit striated myogenesis, but attenuated smooth muscle actin expression and reduced peristaltic activity. Inhibition of c-kit failed to inhibit peristalsis. These results suggest that striated myogenic precursors are resident along the entire length of the esophagus by day 14.5 and do not migrate along the esophagus after E14.5. Induction of myogenesis craniocaudally appears to require physical continuity of the esophagus and is not inhibited by FGF-2. Finally, peristalsis in E14.5 esophagi appears not to be regulated by interstitial cells of Cajal.

Adjustable and non-adjustable strabismus surgery: a retrospective case-matched study.

Adjustable suture strabismus surgery was introduced to improve results in unpredictable strabismus cases. However, its usage is increasing and in some centres is routine. The present authors propose that the routine use of the adjustable suture technique can only be justified if it can be shown to confer an advantage to the patient. In a retrospective analysis of matched data, they compared the results of their adjustable with non-adjustable strabismus surgery. The adjustable suture procedures performed during a 5-year period, on non-thyroid eye disease patients, were matched to non-adjustable cases according to the type and aetiology of strabismus and the magnitude of deviation. Pairs were matched as closely as possible according to age and strabismus surgery history. All cases were incomitant. The surgical results of the two groups were analysed with regard to the pre-operative and post-operative angles of deviation, the post-operative drift, and a successful outcome, pre-defined by carefully selected criteria. Twenty-six cases were analysed in each of the two groups. Mean pre- and post-operative angles of deviation showed no significant difference between the two groups. 'Success' rates were 81% in the adjustable group and 88% in the non-adjustable group. Given that the success rate of the two techniques is similarly high, a much larger study is required to detect a difference in results, with statistical significance. The authors conclude that there is currently insufficient evidence that patients, without thyroid eye disease, benefit from the longer and potentially uncomfortable procedure of adjustable suture strabismus surgery to support its rapidly growing use and that a prospective randomised controlled trial is indicated.

The usefulness of Vistech and FACT contrast sensitivity charts for cataract and refractive surgery outcomes research.

AIM: To investigate the repeatability and sensitivity of two commonly used sine wave patch charts for contrast sensitivity (CS) measurement in cataract and refractive surgery outcomes. METHODS: The Vistech CS chart and its descendant, the Functional Acuity Contrast Test (FACT), were administered in three experiments: (1) Post-LASIK and age matched normal subjects; (2) Preoperative cataract surgery and age matched normal subjects; (3) Test-retest repeatability data in normal subjects. RESULTS: Contrast sensitivity was similar between post-LASIK and control groups and between the Vistech and FACT charts. The percentage of subjects one month post-LASIK achieving the maximum score across spatial frequencies (1.5, 3, 6, 12, 18 cycles per degree) were (50, 33, 13, 13, 0 respectively) for FACT, but only (0, 0, 13, 4, 0 respectively) for Vistech. A small number of cataract patients also registered the maximum score on the FACT, but up to 60% did not achieve the minimum score. Test-retest intraclass correlation coefficients varied from 0.28 to 0.64 for Vistech and 0.18 to 0.45 for FACT. Bland-Altman limits of agreement across spatial frequencies were between +/-0.30 and +/-0.85 logCS for Vistech, and +/-0.30 to +/-0.75 logCS for FACT. DISCUSSION: The Vistech was confirmed as providing poorly repeatable data. The FACT chart, likely because of a smaller step size, showed slightly better retest agreement. However, the reduced range of scores on the chart due to the smaller step size led to ceiling (post-LASIK) and floor (cataract) effects. These problems could mask subtle differences between groups of patients with near normal visual function as found post-refractive or cataract surgery. The Vistech and FACT CS charts are ill suited for refractive or cataract surgery outcomes research.

Ophthalmic complications of childhood medulloblastoma.

BACKGROUND: To study the ophthalmic complications and sequelae in children surviving medulloblastoma in order to assess the need for therapeutic intervention by the ophthalmologist. PROCEDURE: We identified all children attending the Leeds General Infirmary and St. James' University Hospital for treatment of medulloblastoma in the period January 1990 to March 1997, and the notes of all surviving patients were reviewed. Those patients who had not had an ophthalmic assessment within the last 6 months were recalled for examination. RESULTS: Twenty-four surviving patients underwent full ophthalmic assessment. The follow-up period ranged between 6 months and 7 years (range 3.6 yr): 66% had ocular symptoms at presentation; 25% developed ocular complications following treatment; 50% were left with ocular sequelae; 41% percent required ophthalmic intervention (25% medical/orthoptic intervention; 16% surgical intervention). CONCLUSIONS: Early (preferably preoperative) referral to the ophthalmology department is important in order to ensure appropriate management of diplopia, preservation of binocular single vision, and prevention of amblyopia in younger children.

Survival, intracranial lesions, and neurodevelopmental outcome in infants with congenital diaphragmatic hernia treated with extracorporeal membrane oxygenation.

OBJECTIVE: Before the use of extracorporeal membrane oxygenation (ECMO), infants with a severe form of congenital diaphragmatic hernia (CDH) had a high mortality and morbidity. Recent studies have shown an improvement in the survival of these infants after ECMO treatment; however, the existing data do not provide sufficient informations regarding the quality of survival and developmental outcome of these infants. The objective of this study was to evaluate survival, intracranial lesions, and the neurodevelopmental outcome of infants with CDH treated with ECMO. METHODS: We retrieved data for 51 (n = 51) infants with CDH who were treated with ECMO at Huntington Memorial Hospital between 1985 and 1994. Their mean gestational age was 38.5 +/- 2.4 weeks (mean +/- SD); their mean birth weight was 3170 +/- 620 gm. Vital signs, arterial blood gases, chest radiographs, cranial and cardiac ultrasonography were routinely obtained before ECMO treatment. Cranial ultrasounds were performed daily on all infants while on ECMO; computerized tomography scans were obtained on all infants after completion of ECMO treatment. The surviving infants were followed at our neonatal follow-up clinic for neurodevelopmental assessment. RESULTS: A total of 39 infants were placed on venoarterial ECMO and 12 infants were placed on venovenous ECMO; a total of 35 infants had CDH repair before ECMO, whereas 16 infants had delayed surgery. A total of 31 infants (61%) survived. The infants who survived had a mean pH of 7.33 +/- 0.20, mean airway pressure of 19.6 +/- 5.8 cm H2O, and an oxygenation index (OI) of 87 +/- 55 before ECMO intervention. The infants who expired (n = 20) had a mean pH of 7.31 +/- 0.15, mean airway pressure of 23.1 +/- 5.5 cm H2O, and a mean oxygenation index of 127 +/- 56 before ECMO treatment. Before ECMO, survivors had a significantly lower oxygenation index and a higher Pao2 compared with nonsurvivors (p < 0.01). A total of 18 infants (35%) had abnormal central nervous system findings. Of the 51 infants, 10 had ventricular dilatation, 6 had intracranial hemorrhage, and 11 had focal or diffuse cerebral atrophy diagnosed by computerized tomography scan or at autopsy (1 patient had an infarct). Eight infants had more than one central nervous system abnormality. A total of 16 survivors had a neurodevelopmental evaluation at 12 months, and 11 of these survivors were evaluated at 24 months of age (Bayley Scales of Infant Development). The developmental progress of these infants falls within the low-average range of cognitive and motor abilities. Their mean Bayley Mental Developmental Index was 85 +/- 25 (50 to 145) at 24 months; their Psychomotor Developmental Index was 89 +/- 21 (50 to 113) at 24 months of age. Follow-up at 4 and 6 years of age is in progress. CONCLUSION: Our preliminary findings indicate that 35% of infants with severe CDH requiring ECMO had central nervous system abnormalities (intracranial lesions, including ventricular dilatation). The survival rate in our study population is consistent with recent reports. As a group, infants with severe CDH display mild neuromotor and cognitive delay in development at 24 months of age.

Learning effects of a back education program.

STUDY DESIGN: This study involved a post-test only, control group design. OBJECTIVES: To analyze the learning effects of back education programs (video and classroom learning). SUMMARY OF BACKGROUND DATA: Previous research has examined lost work time and workers compensation costs but has not addressed the learning effects of back schools. This study used the American Back School as the education intervention. The American Back School teaches students to maintain the lumbarlordosis while lifting. METHODS: The subjects (n = 205) were assigned to three groups through modified randomization. Three employees who previously sustained low back injury were placed in the back school group. The back school group, Group 1, (n = 74) attended a back school program that included cognitive learning strategies and practice in correct lifting. A video group, Group II, (n =64) viewed a similar program that consisted of spinal anatomy and biomechanics and instruction in correct lifting technique. A control group, Group III, (n = 67) received no back education. One week after the education intervention, 145 of the subjects from the three groups had the lumbar lordosis measured with a flexible ruler while assuming a lifting position. The ruler was placed over the lumbar spinous processes, and the lordotic angle was calculated A 12-item multiple choice test and a 10-item. Likert scale were administrated to 199 of the subjects in the three groups to determine the cognitive learning effect and the perceived relevance of the program, respectively. RESULTS: Multivariate analysis of variance was used and demonstrated significant differences between the back school group and the control group on the cognitive, psychomotor, and affective measures at the 0.001 level. No significant differences were found between the video and control groups on the measures with additional univariate testing. CONCLUSIONS: The results indicate that the back school is an effective tool for influencing lifting posture and conveying information regarding spinal mechanics and lifting technique. In addition, the back school videos may not be an effective means of preventing low back injury.

Use of pulse oximetry to monitor venous saturation during extracorporeal life support.

OBJECTIVE: To assess the ability of two different pulse oximeters to display continuous venous oxygen saturation through an extracorporeal bypass circuit with a degree of accuracy comparable to direct in-line oximetry. DESIGN: Prospective, comparison study of pulse oximeters (test oximeter 1 or test oximeter 2) and an in-line oximeter (test oximeter 3). SETTING: A tertiary care neonatal intensive care unit. PATIENTS: Sixty-five consecutive neonates with severe cardiorespiratory failure undergoing extracorporeal life support. INTERVENTIONS: The accuracy of the oximeters was determined by simultaneously comparing the saturation displayed by the pulse oximeters (test oximeters 1 and 2) and/or the in-line oximeter (test oximeter 3) with the measured fractional venous oxygen saturation obtained at regular intervals from the extracorporeal circuit. MAIN OUTCOME MEASURES: Venous oxygen saturation was the criterion standard used to determine accuracy. Bias was defined as the mean difference between observed pulse oximeter or in-line oximeter values and the measured venous oxygen saturation. Mean biases were calculated for venous oxygen saturation measurements between 55% and 99% at intervals of 10%. Precision (the standard deviation of the bias) was calculated for low (55% to 75%), medium (76% to 81%), and high (82% to 99%) venous oxygen saturation values. A total of 983 venous oxygen saturation measurements were made and compared with simultaneous oximeter readings from test oximeter 1 (n = 600), test oximeter 2 (n = 478), and test oximeter 3 (n = 587). RESULTS: Test oximeter 1 was the most precise instrument at each level of venous oxygen saturation (SD, 4.0 to 4.8). Test oximeter 3 demonstrated the most consistent mean bias (range, 8), but was the most inaccurate oximeter across all levels of venous oxygen saturation. CONCLUSIONS: In addition to its known clinical usefulness, pulse oximetry may serve as an adequate substitute for in-line oximetry during extracorporeal life support.

Isolated vitamin E deficiency and progressive ataxia.

A case of progressive spinocerebellar syndrome due to isolated vitamin E deficiency is reported. Measurement of the vitamin E concentration in serum should be included when investigating all children with unexplained, progressive ataxia, even in the absence of malabsorption. Replacement treatment in patients with a vitamin E deficiency can arrest or improve the associated neurological disorder.

Palmar digital neurectomy in horses. 57 cases (1984-1990).

The medical records of 57 horses that had palmar digital neurectomy performed between 1984 and 1990 were reviewed. Neurectomies were performed either by transection and electrocoagulation (47 horses) or by the guillotine technique (10 horses). Middle-aged geldings, Quarter Horses, and Thoroughbreds were significantly over-represented when compared with the hospital population. Horses used as hunter/jumpers also appeared to be over-represented. Complications occurred in 17 (34%) of the 50 horses for which follow-up information was obtained. Recurrence of heel pain was the most common complication (14 horses). Palpable painful neuromas were detected in three horses. One year after neurectomy, 74% of the horses were sound; this decreased to 63% after 2 years.

Secondary exotropia: a retrospective analysis of matched cases.

Secondary exotropia, that is exotropia following surgery for esotropia, remains frustratingly common, even among experienced strabismologists. In this study, we have compared a group of secondary exotropia cases with a matched group of cases of residual esotropia. Of the factors analyzed, only the presence of an A- or V-pattern preoperatively (P = .0077), the presence of limited postoperative adduction (P < .001), and postoperative binocular function (P = .0073) identified the secondary exotropes. The presence of reduced adduction postoperatively in subjects with secondary exotropia was a poor prognostic sign with 11 of the 13 cases requiring further surgery for poor cosmesis. The authors suggest two subclassifications of secondary exotropia.

Duodenal leiomyoma associated with colic in a two-year-old horse.

A 2-year-old horse with signs of colic, reflux on nasogastric intubation, and large colon distention on transrectal palpation was found to have a leiomyoma involving the duodenum. The mass was excised without penetration of the lumen of the small intestine, and the horse recovered without complications.

Complete excision of a fractured fourth metatarsal bone in eight horses.

Proximal open comminuted fractures of the fourth metatarsal bone (Mt IV) in eight horses were treated by complete removal of the affected bone and antimicrobial therapy. Two horses had concurrent septic arthritis of the tarsocrural or distal tarsal articulations, and five horses had radiographic evidence of osteomyelitis and sequestration of the affected bone. Five horses became athletically sound for their intended use, two horses with septic arthritis had residual lameness but were pasture sound, and one horse was lost to follow-up. Excision of the entire bone appears to be an acceptable treatment of open comminuted fractures of the proximal one-third of Mt IV that do not respond to more conservative modes of therapy.