bluuebunny/crossref_metadata_2025 huggingface dataset:
Assay of Amphetamine in Formulations with Thyroid, Phenobarbital, Atropine, and Aloin
Authors: Mccullough Robert W
Published: February 2020

The USP XVII partition-chromatographic method was found unsuitable for the assay of amphetamine in commercial formulations with thyroid, phenobarbital, atropine, and aloin. A method employing distillation, extraction, and ultraviolet absorbance measurement was applied to the determination of amphetamine in eight samples of such commercial preparations. Results ranged from 95.6 to 102.0% of the label declarations. Standard recoveries of amphetamine from solutions and simulated tablet mixtures averaged 99.0%. A collaborative study was completed for two authentic tablet mixtures and two commercial preparations. Collaborators' results are reported in duplicate, based on two different methods of correction for general background absorption. Recoveries for the two tablet mixtures averaged 96.4 ± 1.8 and 98.8 ± 2.8%, respectively. Results for the commercial tablets averaged 95.3 ± 1.2 and 94.9 ± 1.4% of the respective label declarations. The method based on AA correction is recommended for adoption as official first action.
Microcoulometric Gas Chromatography: Improvements in Instrumentation
Authors: Giuffrida Laura , Ives N Fred
Published: February 2020

Microcoulometric gas chromatography has been available for many years for the specific determination of chlorine and sulfur in pesticides and other compounds. The less specific electron capture has been more widely used in many cases because of its higher sensitivity and also because it is decidedly easier to operate. For more functional microcoulometric equipment, changes have been made that simplify connections and reduce dead volume. The substitution of air as the carrier gas has been successful as well as practical. Additional aspects have been examined for optimum and efficient application of this system.
Collaborative Study on a Modified STPB Method for K2O in Fertilizers
Authors: Hambleton Larry G
Published: February 2020

A collaborative study was conducted on a modification of the official STPB method for K2O in fertilizers, 2.085. The modified method uses an aliquot from the direct available P2O5 extract, thus eliminating a separate sample weighing and solution preparation. Results by the modified method and by the official STPB method from 13 laboratories on four fertilizer samples and a potassium dihydrogen phosphate standard are reported and evaluated. The modification of the official method is recommended for adoption as official first action.
m-SuIfobenzaldehyde in FD&C Violet No. 1
Authors: Marmion Daniel M
Published: February 2020

An unknown substance present in FD&C Violet No. 1 has been identified as m-sulfobenzaldehyde containing a small amount of p-sulfobenzaldehyde. Identification is based on the coincidence of the UV, IR, and NMR spectra of the unknown, as well as the chromatographic retention volume of the unknown, with those of m-sulfobenzaldehyde. The presence of some p-sulfobenzaldehyde is shown by NMR data. A method is also described for the determination of m-sulfobenzaldehyde and the estimation of p-dimethylaminobenzaldehyde, p-dimethylaminobenzoic acid, and ethylbenzylanilinesulfonic acid.
Fluorometric Analysis of Selenium in Plants
Authors: Olson O E
Published: February 2020

A previously reported method for the determination of Se in biological materials has been slightly modified for use on plant materials. Based on a wet digestion and measurement of the fluorescence of the piazselenol formed on reaction with 2,3-diaminonaphthalene, the method as used is sensitive to about 0.02 μg Se. The results of several studies of the method, including a collaborative study, are reported. This method is recommended for adoption as official first action.
Extraction and Analysis of Aflatoxins from Cured and Aged Meats
Authors: Bullerman Lloyd B , Hartman Paul A , Ayres John C
Published: February 2020

A method is presented that is suitable for the analysis of aflatoxins in meats. Ham, bacon, salami, and fresh beef were treated with four levels of aflatoxins, and the toxins were recovered by chloroform extraction. A silica gel column was used to partially purify the chloroform extract, when necessary, and the aflatoxin levels were quantitatively measured by visual comparison with aflatoxin standards on TLC plates. Concentrations of aflatoxin B1 in meat as low as 2.5 ppb could be detected with this method.
Paper Chromatographic Detection of Adulteration in Dark Colored Fruit Juices
Authors: Fitelson J
Published: February 2020

Individual and collaborative tests were made to demonstrate the differences between fat values obtained by the “washed” and “unwashed” methods and to define the crude fat method that yields the true fat values. In an individual study on 18 samples and in a collaborative test by 7 participants on 20 commercial feed samples, the fat values by the two methods were identical on many samples; the washed method yielded lower fat values on certain samples and higher values on other samples. The differences were as much as –49% or +64%. The results were statistically evaluated. Based on these results, it is recommended that a statement be included in method 22.033 for aqueous extraction of samples containing large quantities of water-soluble substances prior to the fat determination.
Dessert Gel Strength Testing. II. Collaborative Study
Authors: Borker Emanuel , Sloman Katherine G
Published: February 2020

Collaborative results on a modified Bloom gelometer method for determining dessert gel strength of gelatin desserts show that the modified method is more precise than 21.012. The modified method uses a lower shot-flow rate (45 g/5 sec compared to 200 g/5 sec), and a different method of sample preparation than the current method. It is recommended that the method described be adopted as official first action to replace 21.012.
Trapping of Dieldrin Lost from Aqueous Algae Cultures
Authors: Wheeler W B
Published: February 2020

The treatment given to aqueous solutions containing dieldrin governed the quantity of insecticide lost by co-distillation with water. Co-distilling dieldrin may be effectively trapped on a short length of a common gas chromatographic column packing (5% DC-200 on 80–100 mesh Gas Chrom Q) and easily eluted for quantitation. Algae present in the aqueous medium reduced the loss of insecticide by this mechanism.
Colorimetric Determination of 2,6-Dichloro-4-Nitroaniline (Dichloran) Residues in Foods
Authors: Heagy James A
Published: February 2020

The colorimetric method of Groves and Chough for determining dichloran residues in food was modified. The modified method uses a Florisil chromatographic column cleanup and a Bratton-Marshall color development procedure. Recoveries ranged from 90 to 100% for eight crops. The method is recommended for further study.
Degradation and Anticarboxylesterase Activity of Disulfoton and Phorate after 60Co Gamma Irradiation
Authors: Grant D L , Sherwood C R , Mccully K A
Published: February 2020

Disulfoton and phorate were subjected to gamma radiation from 60Co at dose levels of 0, 0.1, 0.5, 1, 2, and 4 Mrad. The inhibition of beef liver carboxylesterases by disulfoton and phorate in vitro was greater with increasing doses of radiation. The degradation of these organophosphorus pesticides was monitored by GLC with electron capture and phosphorus detectors, by TLC with detection by Brilliant green, and by enzyme inhibition with 5-bromoindoxyl acetate as substrate. The pesticides were degraded to the greatest extent in hexane or acetone solution. Less decomposition occurred at low temperatures. The sulfoxide and oxygen analog were present in most irradiated samples. The sulfone, oxygen analog sulfone, and oxygen analog sulfoxide were present in some of the disulfoton and phorate samples which were irradiated with 4 Mrad.
Stability of Chlortetracycline in Pelleted Feeds
Authors: Katz Stanley E , Fassbender Carol A , Hain Leslie J
Published: February 2020

The stability of chlortetracycline in pelleted feeds was examined. A poultry feed was pelleted and stored at 20, 30, and 40°C a n d compared to the mash of these feeds. The microbiological potencies, total chlortetracycline content, and epichlortetracycline levels were measured over a period of five weeks. The temperature of storage was found to be the greatest factor in the loss of antibiotic potency.
Identification of Cadmium, Copper, Nickel, Silver, and Zinc in Silver Brazing Alloys by Paper Chromatography
Authors: Fitzgerald James W
Published: February 2020

Metals in silver brazing alloys are detected by paper chromatography on paper treated with di-(2-ethylhexyl) orthophosphoric acid. The developed paper is sprayed with dithizone solution to visualize silver, zinc, and cadmium spots; quercetin solution is used to detect copper and nickel.
Chemical Method for the Determination of Vitamin D in Evaporated Milk With Elimination of Cholesterol by Digitonin Precipitation
Authors: Eisses J , Vries H Dk
Published: February 2020

The colorimetric method of Jones et al. for the determination of vitamin D in evaporated milk, based on theUSPXVI method, was modified to obtain a simpler colorimetric measurement and more accurate results. The main modification is the elimination of nearly all cholesterol, according to the procedure of Den Herder for the determination of the sterol content of fats, by precipitation with digitonin in the saponified mass. The Florex column, used in the procedure of Jones et al. for the elimination of decomposition products of vitamin A, was omitted since it gave high blank values; an alumina column was substituted. The resulting method, when applied to samples of evaporated milk to which a known quantity of vitamin D had been added, showed a recovery of 78% with a standard deviation of 6%, using a calibration curve based on crystalline vitamin D. Data from these measurements, as well as data from vitamin D determination on several brands of fortified and unfortified evaporated milk, are presented.
Study of the Performance of Gas Chromatographic Columns Under Severe Injection Loading
Authors: Thompson John F , Walker Annita C , Moseman Robert F
Published: February 2020

A systematic study was conducted to observe the effect on column performance of a series of 600 consecutive injections of human adipose tissue extract, both cleaned and uncleaned. Ten different column packings were used and included single and mixed nonpolar and polar liquid phases. The column characteristics observed were peak height response, efficiency, on-column conversion of p,p’-DDT to p,p’- DDD, and peak configuration. Repetitive injections of uncleaned and high lipid content human adipose tissue extract resulted in decreased performance of most columns in response, efficiency, and compound conversion. However, all columns could be maintained and restored to full or nearly full performance capacity by daily changing of the glass injection port insert used for off-column injection and the glass wool plug at column inlet.
Collaborative Study of Gas Chromatographic and Infrared Methods for Dacthal Formulations
Authors: Wapensky Lawrence A
Published: February 2020

Five granular formulations containing approximately 2.4–75.0% Dacthal were sent to seven collaborators for GLC and IR analysis. Acetone and benzene were compared as extraction solvents. In the GLC analysis, Dacthaland hexachlorobenzene (a constituent of the commercial product) were separated on a 10% UC-98 column and detected by a flame ionization detector. Dacthal is determined at the IR absorption at 964 cm–1. The method is recommended for adoption as official first action with benzene as the preferred extraction solvent.
Note on the Analysis ot Chlorate Defoliants and Weed Killers
Authors: Roth Fred J
Published: February 2020

The chlorate moiety in chlorate-containing defoliant and weed killer formulations can be analyzed for conformity to guarantee as follows: quantitative release of available chlorine from hydrochloric acid by the chlorate moiety, release of iodine from a potassium iodide solution by the chlorine, and determination of iodine released by titration with standardized sodium thiosulfate.
High Correlation between Ethanol Concentrations in Postmortem Femoral Blood and in Alternative Biological Specimens, but Large Uncertainty When the Linear Regression Model Was Used for Prediction in Individual Cases
Authors: Thelander G , Kugelberg F C , Jones A W
Published: February 2020

In connection with medicolegal autopsies peripheral blood (e.g. from a femoral vein) is the specimen of choice for toxicological analysis, although alternative specimens are also sometimes submitted, such as bile, cerebrospinal fluid (CSF), vitreous humor (VH), bladder urine, pleural effusions and/or lung fluid. Ethanol concentrations were determined in duplicate in femoral blood and in various alternative biological specimens by headspace gas chromatography. The analysis was carried out on two different fused silica capillary columns furnishing different retention times for ethanol and both n-propanol and t-butanol were used as internal standards. The results were evaluated by linear regression using blood alcohol concentration (BAC) as dependent or outcome variable and the concentrations in an alternative specimen as independent or predictor variable. The Pearson correlation coefficients were all statistically highly significant (P < 0.001); r = 0.94 (bile), r = 0.98 (CSF), r = 0.97 (VH), r = 0.92 (urine), r = 0.94 (lung fluid) and r = 0.96 (pleural cavity effusions). When the regression model was used to predict femoral BAC from the mean concentration in an alternative specimen the mean and 95% prediction intervals were 1.12 ± 0.824 g/L (bile), 1.41 ± 0.546 g/L (CSF), 1.15 ± 0.42 g/L (VH), 1.29 ± 0.780 g/L (urine), 1.25 ± 0.772 g/L (lung fluid) and 0.68 ± 0.564 g/L (pleural cavity effusions). This large uncertainty for a single new observation needs to be considered when alcohol-related deaths are evaluated and interpreted. However, the analysis of alternative specimens is recommended in medical examiner cases to provide supporting evidence with regard to the origin of ethanol, whether this reflects antemortem (AM) ingestion or postmortem (PM) synthesis.
Network Agenda Setting, Partisan Selective Exposure, and Opinion Repertoire: The Effects of Pro- and Counter-Attitudinal Media in Hong Kong
Authors: Chen Hsuan-Ting , Guo Lei , Su Chris Chao
Published: February 2020

Using data from a content analysis of partisan media and a public opinion survey administered in Hong Kong, this study incorporates selective exposure and deliberation literature into the network agenda-setting (NAS) model to test media effects on people’s perception of the relationship between Hong Kong and mainland China. This study advances the NAS literature by examining the effects of different media types (i.e., pro- and counter-attitudinal media), considering the patterns of media consumption (i.e., engagement in selective exposure or not), and differentiating between the NAS effects on one’s own opinion repertoire and the oppositional opinion repertoire (i.e., thoughts about how oppositional others perceive the issue). The findings of the study demonstrate that the network agenda of pro-attitudinal media was significantly correlated with both one’s own and oppositional opinion repertoires for those who engaged in partisan selective exposure. For those who did not engage in partisan selective exposure, the network agenda of counter-attitudinal media was significantly related to the oppositional opinion repertoire and the findings for one’s own opinion repertoire were mixed.
Examining Keyboard Bitonality in the Middle-Period Music of Karol Szymanowski
Authors: Reese Alan
Published: February 2020

A characteristic technique of Karol Szymanowski’s middle-period style (1914–18) is “keyboard bitonality”: the juxtaposition of the black-key pentatonic and white-key diatonic scales. To explore Szymanowski’s treatment of keyboard bitonality, I introduce the scalar alignment network, a biscalar landscape of all possible pairings of black- and white-key pitch classes that highlights the effects of a particular alignment, such as the resultant pitch-class pairings and intervallic patterns. To accomplish this, I employ a variety of transformational tools, including diatonic transpositions, Julian Hook’s (2007) interscalar transformations, and what I call SHIFT transformations. Analyzed works include: Masks (1916), Métopes (1915), Myths (1915), Twelve Etudes (Op. 33, 1916), and Violin Concerto No. 1 (1916).
Improved LbCas12a variants with altered PAM specificities further broaden the genome targeting range of Cas12a nucleases
Authors: Tóth Eszter , Varga Éva , Kulcsár Péter István , Kocsis-Jutka Virág , Krausz Sarah Laura , Nyeste Antal , Welker Zsombor , Huszár Krisztina , Ligeti Zoltán , Tálas András , Welker Ervin
Published: February 2020

The widespread use of Cas12a (formerly Cpf1) nucleases for genome engineering is limited by their requirement for a rather long TTTV protospacer adjacent motif (PAM) sequence. Here we have aimed to loosen these PAM constraints and have generated new PAM mutant variants of the four Cas12a orthologs that are active in mammalian and plant cells, by combining the mutations of their corresponding RR and RVR variants with altered PAM specificities. LbCas12a-RVRR showing the highest activity was selected for an in-depth characterization of its PAM preferences in mammalian cells, using a plasmid-based assay. The consensus PAM sequence of LbCas12a-RVRR resembles a TNTN motif, but also includes TACV, TTCV CTCV and CCCV. The D156R mutation in improved LbCas12a (impLbCas12a) was found to further increase the activity of that variant in a PAM-dependent manner. Due to the overlapping but still different PAM preferences of impLbCas12a and the recently reported enAsCas12a variant, they complement each other to provide increased efficiency for genome editing and transcriptome modulating applications.
Metacognitive domain specificity in feeling-of-knowing but not retrospective confidence
Authors: Mazancieux Audrey , Dinze Claire , Souchay Céline , Moulin Chris J A
Published: February 2020

Previous research has converged on the idea that metacognitive evaluations of memory dissociate between semantic and episodic memory tasks, even if the type of metacognitive judgement is held constant. This often observed difference has been the basis of much theoretical reasoning about the types of cues available when making metacognitive judgements of memory and how metacognition is altered in memory pathologies. Here, we sought to revisit the difference between episodic and semantic feeling-of-knowing (FOK) judgements in the light of recent research which has supported a domain general account of metacognition. One hundred participants performed classical episodic and semantic memory tasks with FOK judgements and confidence judgements. Using the meta-d′ framework, we applied a hierarchical Bayesian model to estimate metacognitive sensitivity and cross-task covariance. Results revealed a significant correlation in metacognitive efficiency (meta-d′/d′) between the episodic memory task and the semantic memory task for confidence judgements; however, no evidence was found for a cross-task correlation for FOK judgements. This supports the view that FOK judgements are based on different cues in semantic and episodic memory, whereas confidence judgements are domain general.
Thiopental Does Not Produce Hyperalgesia: A Laboratory Study Using Two Human Experimental Pain Models
Authors: Arout Caroline A , Petrakis Ismene L , Ralevski Elizabeth , Acampora Gregory , Koretski Julia , DeNegre Diana , Newcomb Jenelle , Perrino Albert C
Published: February 2020

Objective

Past investigations assessing the effects of thiopental on pain are conflicting. Although several studies demonstrate hyperalgesia as a result of barbiturate administration, others show analgesia. Our objective was to assess the effects of an infusion of the GABAA agonist thiopental, compared with placebo, in healthy participants on two subjective experimental pain paradigms: noxious electrical stimulation and intradermal capsaicin.

Methods

For electrical stimulation, the milliamps required to achieve pain threshold and tolerance were recorded, and the percent change from baseline was determined for each infusion condition. In the intradermal capsaicin condition, the area of hyperalgesia was determined by von Frey technique pre- and postinfusion, and the percent change in the area of hyperalgesia was calculated.

Results

Though thiopental infusion resulted in an increase in the electrical stimulation current required to elicit pain threshold or reach pain tolerance when compared with baseline, this finding was not statistically significant. In the intradermal capsaicin condition, there was a statistically significant difference in overall pre- and postinfusion pain interpretation, as measured by the McGill Pain Questionnaire (P < 0.05), but there was no significant difference in area of hyperalgesia.

Conclusions

In this human study of thiopental’s effects on two experimental pain models, our results show that thiopental does not induce hyperalgesia.
Determining the Biological Mechanisms of Action for Environmental Exposures: Applying CRISPR/Cas9 to Toxicological Assessments
Authors: Lujan Henry , Romer Eric , Salisbury Richard , Hussain Saber , Sayes Christie
Published: February 2020

Toxicology is a constantly evolving field, especially in the area of developing alternatives to animal testing. Toxicological research must evolve and utilize adaptive technologies in an effort to improve public, environmental, and occupational health. The most commonly cited mechanisms of toxic action after exposure to a chemical or particle test substance is oxidative stress. However, because oxidative stress involves a plethora of genes and proteins, the exact mechanism(s) are not commonly defined. Exact mechanisms of toxicity can be revealed using an emerging laboratory technique referred to as CRISPR (clustered regularly interspaced short palindromic repeats). This article reviews the most common CRISPR techniques utilized today and how each may be applied in Toxicological Sciences. Specifically, the CRISPR/CRISPR-associated protein complex is used for single gene knock-outs, whereas CRISPR interference/activation is used for silencing or activating (respectively) ribonucleic acid. Finally, CRISPR libraries are used for knocking-out entire gene pathways. This review highlights the application of CRISPR in toxicology to elucidate the exact mechanism through which toxicants perturb normal cellular functions.
VISUAL AND ANATOMIC OUTCOMES OF PEDIATRIC ENDOSCOPIC VITRECTOMY IN 326 CASES
Authors: Nagiel Aaron , Yang Unikora , Reid Mark W. , Anulao Kathleen J. , Say Emil A.T. , Wong Sui Chien , Lee Thomas C.
Published: February 2020

Purpose:

To report on the indications, outcomes, and complications of endoscopic vitrectomy in a large cohort of pediatric vitreoretinal patients.

Methods:

This is a retrospective interventional case series consisting of 244 eyes of 211 patients aged 18 years or younger undergoing a total of 326 endoscopic vitrectomies from 2008 to 2017. A 23-gauge vitrectomy was performed with use of a 19-gauge endoscope.

Results:

Two hundred and eleven patients with a mean age of 7.5 years (range: 0–18 years) and median follow-up since last surgery of 28 months (range: 3 months–8.7 years) were included. The most common indication for endoscopic vitrectomy was retinal detachment (234/326; 72%) with proliferative vitreoretinopathy (162/234; 69%). Other diagnoses included trauma (25%), retinopathy of prematurity (15%), and glaucoma (9%). Twenty-five percent of surgeries (80/326) were performed on eyes with significant corneal opacities. Retinal reattachment was achieved in 67% of eyes with retinal detachment (119/178). Visual acuity improved in 26% of retinal detachment eyes versus 53% of nonretinal detachment eyes (P = 0.005). Surgical complications included band keratopathy (15%), hypotony (8%), cataract (7%), and elevated intraocular pressure (3%).

Conclusion:

In this large series of pediatric endoscopic vitreoretinal surgeries, anatomic outcomes and complication rates were comparable with previous studies.
Hard Palate Mucoperiosteal Transplantation for Defects of the Upper Eyelid: A Pilot Study and Evaluation
Authors: Yue Han , Tian Lijia , Bi Yingwen , Qian Jiang
Published: February 2020

Purpose:

To use hard palate mucoperiosteum to reconstruct the upper eyelid wisely and to evaluate its function and outcome.

Methods:

In this case series, medial or lateral defects of the upper eyelid were reconstructed with a hard palate mucoperiosteum graft and a bandage contact lens to protect the cornea. Slit-lamp examinations, in vivo confocal microscopy, patient surveys, and pathologic examinations were performed as evaluations.

Results:

Seven patients were included in this study. The average follow-up time was 21.9 months. Postoperatively, all patients maintained their preoperative corneal transparency, and the best-corrected visual acuities remained stable. Postoperative corneal examination by in vivo confocal microscopy was similar to the normal contralateral eye in all cases. All hard palate mucoperiosteal grafts merged smoothly with the normal tarsoconjunctiva. The mean ratio of the graft length to the upper eyelid decreased from 48.6% during the operation to 32.2% during the follow-up; the average shrinkage rate was 16.3% ± 7.1%. Both in vivo confocal microscopy and the pathologic examinations showed that stratified squamous epithelium comprised the main part of the hard palate graft. All patients could blink normally and had a relatively normal appearance. All patients were satisfied with the overall outcome of this therapy. Main complications included loss of eyelashes (100%), abnormal curvature of the eyelid (28.5%), mild lagophthalmos (14.3%), trichiasis (14.3%), and slight exfoliation of the corneal epithelium (42.8%).

Conclusions:

not only effectively reconstructs the upper eyelid but also provides protection for the cornea.
Retrospective Analysis of Vancomycin Use in Febrile Neutropenic Patients
Authors: Duco Marissa R. , Przybylski Daniel J. , Cosimi Reese A. , Reeves David J.
Published: February 2020

Background

Febrile neutropenia is a complication of cancer treatment that can result in life-threatening infections. Guidelines recommend empiric use of vancomycin in febrile neutropenia for patients with specific risk factors for gram-positive infection. The purpose of this study is to evaluate the guideline criteria for vancomycin use in patients with febrile neutropenia by describing clinical outcomes and identifying potential areas for practice improvement.

Methods

This study was a retrospective review of 275 patients. The primary outcome was to compare the number of patients meeting the criteria for vancomycin in those receiving and not receiving vancomycin. Secondary outcomes were to compare the guideline criteria in patients with and without identified gram-positive infections, determine the accuracy of the guideline criteria for vancomycin use in predicting gram-positive infections, assess discontinuation of vancomycin at 48 hours, and compare clinical outcomes between those receiving and not receiving vancomycin.

Results

Of the identified febrile neutropenia patients, 91.3% met the criteria for empiric vancomycin use. Although 85.1% of patients tested negative for gram-positive bacteria, 89.7% of them met the criteria to receive vancomycin. Discontinuation of vancomycin within 48 hours occurred in 56.4% of patients. Clinically, those receiving vancomycin had a significantly longer median time to defervescence, length of stay, and duration of antibiotics.

Conclusion

Vancomycin use is common, and despite adherence to guideline concordant prescribing, those receiving vancomycin had poorer clinical outcomes. There is a need for identification of more specific risk factors for gram-positive infections, and more education on the appropriate use of vancomycin to promote proper utilization and ensure optimal patient outcomes.
Effects on phacoemulsification efficiency and chatter at variable longitudinal ultrasound settings when combined with constant torsional energy
Authors: Bohner Austin , Peterson John S. , Wright Alex J. , Mamalis Christina , Bernhisel Ashlie , Zaugg Brian , Barlow William R. , Olson Randall J. , Pettey Jeff H.
Published: February 2020

Purpose:

To evaluate longitudinal power settings for optimally efficient lens fragment removal, using the Centurion machine.

Setting:

John A. Moran Eye Center, University of Utah, Salt Lake City, USA.

Design:

Experimental study.

Methods:

Porcine lens nuclei were cut into 2.0 mm cubes. Experiments were conducted at 100% torsional power; vacuum set at 500 mm Hg, aspiration 50 mL/min, and intraocular pressure 110 mm Hg. A 20-degree tip with a 30-degree bevel was used. Longitudinal power was tested between 20% and 100%. Efficiency (time for fragment removal) and chatter (the number of times the fragment bounced from the tip) were measured.

Results:

A linear increase in efficiency was observed from 20% to 100% longitudinal power (R2 = 0.9281, slope = −0.0271). An efficiency slope change occurred at 60% power, with the largest incremental change in efficiency between 20% and 60% (R2 = 0.9756, slope = −0.0394) and a lesser change between 60% and 100% (R2 = 0.9827, slope = −0.0121). Chatter analysis showed minimal events at 20% to 60%, but a significant increase at >80% (P = .005). This increase appeared to be incremental (R2 = 0.8929).

Conclusions:

Increasing longitudinal power, with all other settings constant, increased efficiency. Greatest efficiency gains were observed between 20% and 60%. At 80% and 100%, chatter events increased significantly. With a goal of recommending optimally efficient settings while minimizing excess energy and chatter, adding 60% of longitudinal power to 100% torsional power was shown to be the best setting to increase efficiency and avoid repulsion in these vacuum and aspiration settings.
Long-term safety of in-the-bag implantation of a supplementary intraocular pinhole
Authors: Trindade Bruno Lovaglio Cançado , Trindade Fernando Cançado , Werner Liliana , Trindade Claudio Lovaglio Cançado
Published: February 2020

Purpose:

To evaluate the long-term effectiveness and safety of the XtraFocus intraocular pinhole (IOPH) when it is implanted inside the capsular bag.

Setting:

Private practice.

Design:

Retrospective consecutive case series.

Methods:

Patients who had an IOPH implanted in the capsular bag together with the primary intraocular lens (IOL) to treat irregular corneal astigmatism secondary to multiple causes were enrolled. The mean follow-up was 16 months (range 7 to 48 months). Patients were assessed in their scheduled follow-up visits. The uncorrected and corrected distance visual acuities were recorded at each visit. An infrared slitlamp photograph was captured and analyzed to verify the presence of interlenticular membrane formation.

Results:

Sixty eyes of 58 patients were analyzed. The mean uncorrected and corrected distance visual acuities improved from logarithm of the minimum angle of resolution 1.34 ± 0.338 and 0.57 ± 0.145 preoperatively to 0.14 ± 0.012 (P < .001) and 0.12 ± 0.008 (P = .001) at 1 year postoperatively, respectively. A mild pinhole decentration was noted in 5 eyes (8.3%). Interlenticular opacification (ILO) was not noted in any patient.

Conclusions:

Implantation of the XtraFocus IOPH inside the capsular bag was a safe technique. Improvement observed in both uncorrected and corrected distance visual acuities was significant and sustained over time. ILO did not occur when this implant was positioned in the capsular bag together with a primary IOL.
Food and Drug Administration Malfunction Recalls of Left Ventricular Assist Devices
Authors: Lugo Baruqui Diego , Maning Jennifer , Chaparro Sandra V.
Published: February 2020

Left ventricular assist devices (LVADs) are being increasingly implanted given the increasing prevalence of patients with advanced heart failure stages. However, they are not exempt from device malfunctions. A PubMed search for the key words (left ventricular assist device malfunction) (ventricular assist system malfunction) was performed. We identified 28 publications in the US Food and Drug Administration (FDA) website database that addressed LVAD malfunction. Twenty-nine FDA recalls were identified regarding LVAD malfunctions: 17 regarding HeartWare ventricular assist device, six for HeartMate II, three for HeartMate 3, and three for total artificial heart. Mechanisms involved in LVAD malfunction include battery malfunction, loose driveline connector, malfunction of the system controller, loose power supply connector ports, malfunction of the driveline splice kit, problems with the percutaneous lead connection, disconnection of the bend relief and outflow graft and outflow graft occlusion among others. Multiple mechanisms could be linked to LVAD malfunction. However, multiple device modifications have been developed over the past decade to avoid recurrent malfunctions. Constant improvements and research in biotechnology are needed to prevent these complications. It remains to be seen if newer generation devices will lead to improved patient outcomes over the long term.
Extracorporeal Life Support in Pediatric Patients with Bronchopulmonary Dysplasia and Associated Pulmonary Hypertension
Authors: Pena Hernandez Alejandra , Carr Nicholas R. , McCurnin Donald , Armijo-Garcia Veronica
Published: February 2020

This retrospective study reviews outcomes of 281 pediatric patients with bronchopulmonary dysplasia (BPD) managed with extracorporeal life support (ECLS). Data from 1982 to 2018 from the Extracorporeal Life Support Organization (ELSO) registry were queried for children aged 60 days to 18 years with a prior diagnosis of BPD, and all patients with secondary pulmonary hypertension (PH) were identified. Overall survival of patients with and without PH was 86.7% and 68.0%, respectively (p = 0.23). There was no report of patients with PH before 2004. Patients with BPD + PH were more likely to have associated intraventricular hemorrhage (p = 0.002) and retinopathy of prematurity (p = 0.05), as well as a greater reported use of sildenafil (p = 0.0001) and milrinone (p = 0.008) before ECLS. The most common primary diagnosis in patients with BPD was viral respiratory infection (45.3%) and in patients with BPD + PH was respiratory failure without mention of infection (40.0%). Inotrope use was the most common complication reported (36.7%) with survival of 54.4%. We conclude that data from the ELSO registry demonstrate reasonable survival in both, patients with BPD and BPD + PH. Thus, patients with BPD and associated PH should be considered candidates for ECLS.
Nurse Faculty Orientation
Authors: Rogers Julia , Ludwig-Beymer Patti , Baker Manisa
Published: February 2020

Background

Nursing faculty orientations vary in length, content, and comprehensiveness; this may influence faculty effectiveness and retention.

Purpose

This review was conducted to identify essential elements for nursing faculty orientation and to develop an orientation checklist and index of mentor-mentee responsibilities.

Methods

An integrative review was conducted using the Ganong approach. The search generated 48 articles that met the inclusion criteria and were evaluated and interpreted.

Results

Essential elements for nursing faculty orientation were identified. Both a comprehensive orientation checklist that encompasses academic culture, teaching, scholarship, and service and an index of mentor-mentee responsibilities were created based on the evidence.

Conclusion

Formal orientation to the academic setting assists nursing faculty through their transition. A comprehensive checklist helps the mentor and mentee to track progress. Addressing the needs of new faculty may result in improved nurse faculty satisfaction, productivity, and retention while producing better student outcomes.
A Case of Delayed Presentation of Transposition of the Great Arteries
Authors: Welsh Alissa , Hoyle John D.
Published: February 2020

Intro

Transposition of the great arteries (TGA) is a rare cyanotic congenital heart defect (CHD) typically presenting the first month of life. Late presentations may occur in patients with associated cardiac anomalies allowing for mixing of oxygenated and deoxygenated blood, such as ventral septal defects or large atrial septal defects (ASD). We present a case of a late-presenting TGA with no ventral septal defect, and only small ASD and patent ductus arteriosus (PDA).

Case

A 2-month-old female infant presented to a rural emergency department with respiratory distress for 1 day. On arrival, she was cyanotic with only mild improvement in oxygen saturations on 15-L non-rebreather. Grade IV/VI murmur was noted, and prostaglandin E was started. She required intubation after becoming apneic and was transported to the local pediatric referral hospital. There, echocardiography showed dextro-type TGA, with 8-mm ASD with minimal gradient, small PDA with left to right flow, and ventral septal bowing. She underwent balloon septostomy and then atrial switch, which was well tolerated.

Discussion

Our case is unique because of the patient's late presentation and prior lack of symptoms, given minimal levels of blood mixing though small ASD and PDA. Most TGA cases are now identified during prenatal ultrasound or with CHD screening pulse oximetry before discharge from the newborn nursery; however rare cases of late-presenting TGA may exist.

Conclusion

Practitioners must maintain consideration of TGA, even after the newborn period, despite advances in newborn CHD screening in infants who present with new-onset respiratory distress without infection.
Unifying the essential concepts of biological networks: biological insights and philosophical foundations
Authors: Kostić Daniel , Hilgetag Claus C. , Tittgemeyer Marc
Published: February 2020

Over the last decades, network-based approaches have become highly popular in diverse fields of biology, including neuroscience, ecology, molecular biology and genetics. While these approaches continue to grow very rapidly, some of their conceptual and methodological aspects still require a programmatic foundation. This challenge particularly concerns the question of whether a generalized account of explanatory, organizational and descriptive levels of networks can be applied universally across biological sciences. To this end, this highly interdisciplinary theme issue focuses on the definition, motivation and application of key concepts in biological network science, such as explanatory power of distinctively network explanations, network levels and network hierarchies.

This article is part of the theme issue ‘Unifying the essential concepts of biological networks: biological insights and philosophical foundations’.
Atypical depression shares genetic predisposition with immuno-metabolic traits: a population-based study
Authors: Badini Isabella , Coleman Jonathan R.I. , Hagenaars Saskia P. , Hotopf Matthew , Breen Gerome , Lewis Cathryn M. , Fabbri Chiara
Published: February 2020

Background

Depression is a highly prevalent and heterogenous disorder. Clinical heterogeneity may reflect different underlying biological mechanisms. This study aims to determine whether atypical depression shows higher heritability and different degree of overlap with polygenic risk for cardio- and immuno- metabolic traits than non-atypical depression.

Methods

Data included 30,069 individuals from the UK Biobank who met criteria for lifetime major depression. Participants reporting both hypersomnia and weight gain were classified as atypical cases (N = 1,854), and the others as non-atypical cases (N = 28,215). Non-atypical cases were further classified as typical depression (i.e. insomnia and weight loss; N = 10,142). Polygenic risk scores (PRS) for 21 traits were generated using genome-wide summary statistics (Bonferroni corrected p=2.2×10−4). Single nucleotide polymorphism (SNP)-based heritability of atypical and typical depression was estimated.

Results

Atypical depression had a higher polygenic risk for BMI (OR=1.20, [1.15-1.26], p=2.37e-14), and C-reactive protein (OR=1.11, [1.06-1.17], p=8.86e-14) vs. non-atypical cases. Leptin PRS was very close to the significance threshold (p=4.13e-04), but the effect disappeared when considering GWAS summary statistics of leptin adjusted for BMI. PRS for daily alcohol use was inversely associated with atypical depression (OR=0.88, [0.84-0.93], p=1.04e-05) vs. non-atypical depression. SNP-based heritability on the liability scale was not significantly different between atypical and typical depression (5.2% and 4.5%, respectively).

Conclusions

Atypical depression shows evidence of distinct genetic predisposition to immune-metabolic traits in line with the previous literature. These genetic signals suggest that biological targets including cardiometabolic or immune pathways may be germane to therapies in individuals with atypical depression.
Estimating population level disease prevalence using genetic risk scores
Authors: Evans Benjamin D. , Słowiński Piotr , Hattersley Andrew T. , Jones Samuel E. , Sharp Seth , Kimmitt Robert A. , Weedon Michael N. , Oram Richard A. , Tsaneva-Atanasova Krasimira , Thomas Nicholas J.
Published: February 2020

Clinical classification is essential for estimating disease prevalence but is difficult, often requiring complex investigations. The widespread availability of population level genetic data makes novel genetic stratification techniques a highly attractive alternative. We propose a generalizable mathematical framework for determining disease prevalence within a cohort using genetic risk scores. We compare and evaluate methods based on the means of genetic risk scores’ distributions; the Earth Mover’s Distance between distributions; a linear combination of kernel density estimates of distributions; and an Excess method. We demonstrate the performance of genetic stratification to produce robust prevalence estimates. Specifically, we show that robust estimates of prevalence are still possible even with rarer diseases, smaller cohort sizes and less discriminative genetic risk scores, highlighting the general utility of these approaches. Genetic stratification techniques offer exciting new research tools, enabling unbiased insights into disease prevalence and clinical characteristics unhampered by clinical classification criteria.
Breadth of concomitant immune responses underpinning viral clearance and patient recovery in a non-severe case of COVID-19
Authors: Thevarajan Irani , Nguyen Thi HO , Koutsakos Marios , Druce Julian , Caly Leon , van de Sandt Carolien E , Jia Xiaoxiao , Nicholson Suellen , Catton Mike , Cowie Benjamin , Tong Steven YC , Lewin Sharon R , Kedzierska Katherine
Published: February 2020

We report the kinetics of the immune response in relation to clinical and virological features of a patient with mild-to-moderate coronavirus disease-19 (COVID-19) requiring hospitalisation. Increased antibody-secreting cells, follicular T-helper cells, activated CD4+ and CD8+ T-cells and IgM/IgG SARS-CoV-2-binding antibodies were detected in blood, prior to symptomatic recovery. These immunological changes persisted for at least 7 days following full resolution of symptoms, indicating substantial anti-viral immunity in this non-severe COVID-19.
T cells limit accumulation of aggregate pathology following intrastriatal injection of α-synuclein fibrils
Authors: George Sonia , Tyson Trevor , Rey Nolwen L. , Sheridan Rachael , Peelaerts Wouter , Becker Katelyn , Schulz Emily , Meyerdirk Lindsay , Burmeister Amanda R. , Steiner Jennifer A. , Escobar Galvis Martha L. , Ma Jiyan , Pospisilik Andrew , Labrie Viviane , Brundin Lena , Brundin Patrik
Published: February 2020

Background: α-Synuclein (α-syn) is the predominant protein in Lewy-body inclusions, which are pathological hallmarks of α-synucleinopathies, such as Parkinson’s disease (PD) and multiple system atrophy (MSA). Other hallmarks include activation of microglia, elevation of pro-inflammatory cytokines, as well as the activation of T and B cells. These immune changes point towards a dysregulation of both the innate and the adaptive immune system. T cells have been shown to recognize epitopes derived from α-syn and altered populations of T cells have been found in PD and MSA patients, providing evidence that these cells can be key to the pathogenesis of the disease. Objective: To study the role of the adaptive immune system with respect to α-syn pathology. Methods: We injected human α-syn preformed fibrils (PFFs) into the striatum of immunocompromised mice (NSG) and assessed accumulation of phosphorylated α-syn pathology, proteinase K-resistant α-syn pathology and microgliosis in the striatum, substantia nigra and frontal cortex. We also assessed the impact of adoptive transfer of naïve T and B cells into PFF-injected immunocompromised mice. Results: Compared to wildtype mice, NSG mice had an 8-fold increase in phosphorylated α-syn pathology in the substantia nigra. Reconstituting the T cell population decreased the accumulation of phosphorylated α-syn pathology and resulted in persistent microgliosis in the striatum when compared to non-transplanted mice. Conclusion: Our work provides evidence that T cells play a role in the pathogenesis of experimental α-synucleinopathy.
Loss of floor plate Netrin-1 impairs midline crossing of corticospinal axons and leads to mirror movements
Authors: Pourchet Oriane , Morel Marie-Pierre , Welniarz Quentin , Sarrazin Nadège , Marti Fabio , Heck Nicolas , Galléa Cécile , Doulazmi Mohamed , Puiggros Sergi Roig , Moreno-Bravo Juan Antonio , Vidailhet Marie , Trembleau Alain , Faure Philippe , Chédotal Alain , Roze Emmanuel , Dusart Isabelle
Published: February 2020

In human, execution of unimanual movements requires lateralized activation of the primary motor cortex, which then transmits the motor command to the contralateral hand through the crossed corticospinal tract (CST). Mutations inNETRIN-1alter motor control lateralization, leading to congenital mirror movements. To address the role of midline Netrin-1 on CST development and subsequent motor control, we analyzed the morphological and functional consequences of floor-plate Netrin-1 depletion in conditional knock-out mice (Shh::cre;Ntn1lox/loxmice).

Here, we show that depletion of floor plate Netrin-1 critically disrupts midline crossing of the CST, whereas the other commissural systems are mostly preserved. The CST defect results in abnormal but functional ipsilateral projections, and is associated with abnormal symmetric movements. Therefore, our study reveals a new role for Netrin-1 in CST development. It also describes a unique mouse model recapitulating characteristics of human congenital mirror movements, through abnormal CST decussation.
Are alpha-band oscillations a default dynamic of the human visual brain, or a product of ongoing visual processes?
Authors: Hohaia Wiremu , Saurels Blake W. , Johnston Alan , Yarrow Kielan , Arnold Derek H.
Published: February 2020

One of the seminal findings of cognitive neuroscience is that the power of alpha-band (∼10 Hz) brain waves, in occipital regions, increases when people close their eyes. This has encouraged the view that alpha oscillations are a default dynamic, to which the visual brain returns in the absence of input. Accordingly, we might be unable toincreasethe power of alpha oscillations when the eyes are closed, above the level that would usually ensue. Here we report counter evidence. We used electroencephalography (EEG) to record brain activity when people had their eyes open and closed, before and after they had adapted to radial motion. The increase in the power of alpha oscillations when people closed their eyes wasenhancedby adaptation to a broad range of radial motion speeds. This effect was greatest for 10Hz motion, but robust for other frequencies, and specifically for 7.5Hz. This last observation is important, as it rules against an ongoing entrainment of activity, at the adaptation frequency, as an explanation for our results. Instead, our data show that visual processes remain active when people close their eyes, and these can be modulated by adaptation to increase the power of alpha oscillations in occipital brain regions.