Supportive therapy during COVID-19: The proposed mechanism of short-chain fatty acids to prevent cytokine storm and multi-organ failure

The world is currently facing the COVID-19 pandemic that is taking a heavy toll on several countries. While many infected patients have a good prognosis, in some cases the progression can be serious and even lead to death. The commonly seen complications are a cytokine storm and multi-organ failure that require intensive care. The mortality of critically ill patients depends on age, sex, immune state or co-morbidities. There is an urgent need to discover a biomarker to identify early on patients at risk of developing serious complications and to find an effective treatment that could prevent disease progression and critical states. Recent investigations have pointed to the possible contribution of intestinal dysbiosis to the pathophysiology of COVID-19. Herein, we hypothesize that butyrate, a short-chain fatty acid initially produced by the gut microbiota, could be administered as supportive therapy to prevent immune system activation and disease progression.

Modification of obturator to femoral nerve transfer for femoral nerve palsy

Postoperative femoral nerve palsy with nerve division is a potentially devastating complication with a poor prognosis, especially when there is a delay in diagnosis. We present a novel 'belt and braces' approach for managing this unusual injury, using a modification of a nerve transfer, which has only been previously reported in the literature three times to our knowledge.

Exhaled nitric oxide in the diagnosis of asthma in adults: a systematic review

OBJECTIVES

To identify and synthesize evidence on the diagnostic accuracy of _FE NO for asthma in adults.

MATERIALS AND METHODS

Systematic searches (nine key biomedical databases and trial registers) were carried out on November 2014. Records were included if they recruited patients with the symptoms of asthma; used a single set of inclusion criteria; measured _FE NO₅₀ in accordance with American Thoracic Society guidelines, 2005 (off-line excluded); reported/allowed calculation of true-positive, true-negative, false-positive and false-negative patients as classified against any reference standard. Study quality was assessed using QUADAS II. Meta-analysis was planned where clinical study heterogeneity allowed. Rule-in and rule-out uses of _FE NO were considered.

RESULTS

A total of 4861 records were identified originally and 1312 in an update. Twenty-seven studies were included. Heterogeneity precluded meta-analysis. Results varied even within subgroups of studies. Cut-off values for the best sum of sensitivity and specificity varied from 12 to 55 p.p.b., but did not produce high accuracy. 100% sensitivity or 100% specificity was reported by some studies indicating potential use as a rule-in or rule-out strategy.

CONCLUSIONS AND CLINICAL RELEVANCE

_FE NO₅₀ had variable diagnostic accuracy even within subgroups of studies with similar characteristics. Diagnostic accuracy, optimal cut-off values and best position for _FE NO₅₀ within a pathway remain poorly evidenced.

Impact of a targeted isolation strategy at intensive-care-unit-admission on intensive-care-unit-acquired infection related to multidrug-resistant bacteria: a prospective uncontrolled before-after study

Isolation of patients with multidrug resistant (MDR) bacteria is recommended to reduce cross-transmission of these bacteria. However, isolation of critically ill patients has several negative side effects. Therefore, we hypothesized that a targeted isolation strategy, based on the presence of at least one risk factor for MDR bacteria, would be not inferior to a systematic isolation strategy at intensive-care unit (ICU) admission. This prospective before-after study was conducted in a mixed ICU, during two 12-month periods, separated by a 1-month 'wash-out' period. During the before period, isolation was systematically performed in all patients at admission. During the after period, isolation was only performed in patients with at least one risk factor for MDR bacteria at admission. During the two periods, routine screening for MDR bacteria was performed at ICU admission, and isolation prescription was modified after receipt of screening result. Primary outcome was the percentage of patients with ICU-acquired infection (ICUAI) related to MDR bacteria, measured from ICU admission until ICU discharge or day 28, whatever happens first. A total of 1221 patients were included. No significant difference was found in ICUAI related to MDR bacteria (85 of 585 (14.5%) vs. 84 of 636 (13.2%) patients, risk difference, -1.3%, 95% confidence interval [-5.2 to 2.6%]) between the two periods, confirming the non-inferiority hypothesis. Our results suggest that targeted isolation of patients at ICU admission is not inferior to systematic isolation, regarding the percentage of patients with ICUAI related to MDR bacteria. Further randomized controlled multicentre studies are needed to confirm our results.

Simultaneous Sketching Aids the Haptic Identification of Raised Line Drawings

Haptically identifying raised line drawings is difficult. We investigated whether a major component of this difficulty lies in acquiring, integrating, and maintaining shape information from touch. Wijntjes, van Lienen, Verstijnen, and Kappers reported that drawings which participants had failed to identify by touch alone could often subsequently be named if they were sketched. Thus, people sometimes needed to externalize haptically acquired information by making a sketch in order to be able to use it. We extended Wijntjes et al.'s task and found that sketching while touching improved drawing identification even more than sketching after touching, but only if people could see their sketches. Our results suggest that the slow, serial nature of information acquisition seriously hampers the haptic identification of raised line drawings relative to visually identifying line drawings. Simultaneous sketching may aid identification by reducing the burden on working memory and by helping to guide haptic exploration. This conclusion is consistent with the finding reported by Lawson and Bracken that 3-D objects are much easier to identify haptically than raised line drawings since, unlike for vision, simultaneously extracting global shape information is much easier haptically for 3-D stimuli than for line drawings.

Multi-centre analysis of incidental findings on low-resolution CT attenuation correction images

OBJECTIVE

To review new incidental findings detected on low-resolution CT attenuation correction (CTAC) images acquired during single-photon emission CT (SPECT-CT) myocardial perfusion imaging (MPI) and to determine whether the CTAC images had diagnostic value and warrant reporting.

METHODS

A multicentre study was performed in four UK nuclear medicine departments. CTAC images acquired as part of MPI performed using SPECT were evaluated to identify incidental findings. New findings considered to be clinically significant were evaluated further. Positive predictive value (PPV) was determined at the time of definitive diagnosis.

RESULTS

Of 1819 patients studied, 497 (27.3%) had a positive CTAC finding. 51 (2.8%) patients had findings that were clinically significant at the time of the CTAC report and had not been previously diagnosed. Only four (0.2%) of these were potentially detrimental to patient outcome.

CONCLUSION

One centre had a PPV of 0%, and the study suggests that these CTAC images should not be reported. Two centres with more modern equipment had low PPVs of 0% and 6%, respectively, and further research is suggested prior to drawing a conclusion. The centre with best quality CT had a PPV of 67%, and the study suggests that CTAC images from this equipment should be reported.

ADVANCES IN KNOWLEDGE

This study is unique compared with previous studies that have reported only the potential to identify incidental findings on low-resolution CT images. This study both identifies and evaluates new clinically significant incidental findings, and it demonstrates that the benefit of reporting the CTAC images depends on the type of equipment used.

Practitioner compression force variability in mammography: a preliminary study

OBJECTIVE

This preliminary study determines whether the absolute amount of breast compression in mammography varies between and within practitioners.

METHODS

Ethics approval was granted. 488 clients met the inclusion criteria. Clients were imaged by 14 practitioners. Collated data included Breast Imaging Reporting and Data System (BI-RADS) density, breast volume, compression and practitioner code.

RESULTS

A highly significant difference in mean compression used by different practitioners (p<0.0001 for each BI-RADS density) was demonstrated. Practitioners applied compression in one of three ways using either low, intermediate or high compression force, with no significant difference in mean compression within each group (p=0.99, p=0.70, p=0.54, respectively). Six practitioners showed a significant correlation (p<0.05) between compression and BI-RADS grade, with a tendency to apply less compression with increasing BI-RADS density. When compression was analysed by breast volume there was a wide variation in compression for a given volume. The general trend was the application of higher compression to larger breast volumes by all three practitioner groups.

CONCLUSION

This study presents an insight into practitioner variation of compression application in mammography. Three groups of practitioners were identified: those who used low, intermediate and high compression across the BI-RADS density grades. There was wide variation in compression for any given breast volume, with trends of higher compression demonstrated for increasing breast volumes. Collation of further studies will facilitate a new perspective on the analysis of practitioner, client and equipment variables in mammography imaging.

ADVANCES IN KNOWLEDGE

For the first time, it has been practically demonstrated that practitioners vary in the amount of compression applied to breast tissue during routine mammography.

A community-based long-term follow up of women undergoing obstetric fistula repair in rural Ethiopia

OBJECTIVES

To assess urinary and reproductive health and quality of life following surgical repair of obstetric fistula.

DESIGN

Follow-up study.

SETTING

A newly established fistula clinic (2004) at Gimbie Adventist Hospital, a 71-bedded district general hospital in West Wollega Zone, in rural Western Ethiopia.

POPULATION

Thirty-eight women (86%) of 44 who had undergone fistula repair were identified in their community.

METHODS

Community-based structured interviews 14-28 months following fistula repair, using a customised questionnaire addressing urinary health, reproductive health and quality of life.

MAIN OUTCOME MEASURES

Urinary health at follow up was assessed as completely dry, stress or urge incontinence, or fistula. King's Health Questionnaire was modified and used for the quality-of-life assessment.

RESULTS

At follow up, 21 women (57%) were completely dry, 13 (35%) suffered from stress or urge incontinence and three (8%) had a persistent fistula. Surgery improved quality of life and facilitated social reintegration to a level comparable to that experienced before fistula development for both women who were dry and those with residual incontinence (P = 0.001). For women still suffering from fistula no change was seen (P = 0.1). Four women became pregnant following their surgery, among which there was one maternal death, three stillbirths and one re-occurrence of fistula.

CONCLUSION

Community-based, long-term follow up after fistula repair succeeded in Western rural Ethiopia. Despite one-third still suffering stress or urge incontinence, the women reported improved quality of life and social reintegration after fistula closure.

Phylogeny of the Colubroidea (Serpentes): New evidence from mitochondrial and nuclear genes

The Colubroidea contains over 85% of all the extant species of snakes and is recognized as monophyletic based on morphological and molecular data. Using DNA sequences (cyt b, c-mos) from 100 species we inferred the phylogeny of colubroids with special reference to the largest family, the Colubridae. Tree inference was obtained using Bayesian, likelihood, and parsimony methods. All analyses produced five major groups, the Pareatidae, Viperidae, Homalopsidae, the Elapidae, and the Colubridae. The specific content of the latter two groups has been altered to accommodate evolutionary history and to yield a more stable taxonomy. We propose an updated classification based on the reallocation of species as indicated by our inferred phylogeny.

Optical modulation and detection in slotted Silicon waveguides

We demonstrate a novel mechanism for low power optical detection and modulation in a slotted waveguide geometry filled with nonlinear electro-optic polymers. The nanoscale confinement of the optical mode, combined with its close proximity to electrical contacts, enables the direct conversion of optical energy to electrical energy, without external bias, via optical rectification, and also enhances electro-optic modulation. We demonstrate this process for power levels in the sub-milliwatt regime, as compared to the kilowatt regime in which optical nonlinear effects are typically observed at short length scales. Our results suggest that a new class of detectors based on nonlinear optics may be practical.

Poor response to ovulation induction is a stronger predictor of early menopause than elevated basal FSH: a life table analysis

BACKGROUND

During the course of assisted reproduction treatment, a number of women exhibit a "poor response" to ovulation induction, or demonstrate an elevated basal FSH level (> or =10 IU/l) at a young age. We sought to determine whether these women are at increased risk of early menopause and poor reproductive performance.

METHODS

A retrospective cohort study included 118 "poor responders" with normal basal FSH level (<10 IU/l), 164 women with raised basal FSH (> or =10 IU/l), and 265 controls, who underwent assisted reproduction treatment between 1987 and 1998. All women were < 40 years of age at the time of treatment and had normal menstrual cycles. Participants were sent a postal questionnaire in 2000-2001, seeking information on ovarian function and reproductive performance following cessation of treatment.

RESULTS

After adjusting for age and smoking habits, women with poor response and raised basal FSH levels were more likely to experience symptoms of the peri-menopause [hazard ratios 2.4, 95% confidence interval (CI) 1.52-3.78, and 2.76, 95% CI 1.78-4.29 respectively, P = 0.0001]. Poor responders were six times and 23 times more likely to experience the menopause within 10 years of treatment than those with raised basal FSH levels and controls respectively (hazard ratio 5.97 and 23.9, P = 0.015 and 0.002 respectively). Poor responders and those with raised basal FSH levels have half the chance of spontaneous conception after discontinuation of treatment compared with controls (P < 0.007).

CONCLUSIONS

Both poor response to ovarian stimulation and raised basal FSH are markers of reduced ovarian reserve and predict an increased risk of early menopause.

Screening for HIV, hepatitis B and C infection in a population seeking assisted reproduction in an inner London hospital

The Human Fertilisation and Embryology Authority requires all sperm donors to be screened for human immunodeficiency virus (HIV), hepatitis B and C and their semen quarantined for six months. No guidelines exist for screening prior to in vitro fertilisation or intracytoplasmic sperm injection. We prospectively analysed the prevalence of these viruses in our patients. Screening detected one case of HIV (0.13%), four of hepatitis C (0.5%) and 14 new cases of hepatitis B (1.7%). The prevalence of hepatitis B and HIV in our antenatal population at this time was 1.4% and 0.8%, respectively. Knowledge allows measures to be taken to reduce the risk of transmission to partner, fetus, new born baby, or by cross-contamination during embryo cryostorage and enables couples to make an informed decision regarding proceeding with treatment. Detection of infection in one partner should no longer preclude fertility treatment.

Mitochondrial DNA phylogeography of the polytypic North American rat snake (Elaphe obsoleta): a critique of the subspecies concept

Subspecies have been considered artificial subdivisions of species, pattern classes, or incipient species. However, with more data and modern phylogenetic techniques, some subspecies may be found to represent true species. Mitochondrial DNA analysis of the polytypic snake, Elaphe obsoleta, yields well-supported clades that do not conform to any of the currently accepted subspecies. Complete nucleotide sequences of the cytochrome b gene and the mitochondrial control region produced robust maximum-parsimony and maximum-likelihood trees that do not differ statistically. Both trees were significantly shorter than a most parsimonious tree in which each subspecies was constrained to be monophyletic. Thus, the subspecies of E. obsoleta do not represent distinct genetic lineages. Instead, the evidence points to three well-supported mitochondrial DNA clades confined to particular geographic areas in the eastern United States. This research underscores the potential problems of recognizing subspecies based on one or a few characters.

The combined effects of plane disorientation and foreshortening on picture naming: one manipulation or two?

Objects disoriented in plane away from the upright and objects rotated in depth producing foreshortening are harder to identify than canonical views. In Experiments 1 and 2, participants named pictures of familiar objects. There was no interaction between plane and depth rotation effects on initial presentation or after practice. Experiment 3 was a dual-task psychological refractory period study. Participants classified a high-low tone with a speeded keypress and then named a canonical, plane-rotated, or foreshortened view of an object. Naming was slower when the picture was presented 50 ms after the tone compared with 800 ms after the tone. Plane rotation effects were reduced (but not eliminated) at the short tone-picture stimulus onset asynchrony, but foreshortening effects were not reduced. The results implicate an early, prebottleneck locus for some processes compensating for plane rotation and a subsequent bottleneck or postbottleneck locus for compensation for foreshortening.

The combined effects of plane disorientation and foreshortening on picture naming: one manipulation or two?

Objects disoriented in plane away from the upright and objects rotated in depth producing foreshortening are harder to identify than canonical views. In Experiments 1 and 2, participants named pictures of familiar objects. There was no interaction between plane and depth rotation effects on initial presentation or after practice. Experiment 3 was a dual-task psychological refractory period study. Participants classified a high-low tone with a speeded keypress and then named a canonical, plane-rotated, or foreshortened view of an object. Naming was slower when the picture was presented 50 ms after the tone compared with 800 ms after the tone. Plane rotation effects were reduced (but not eliminated) at the short tone-picture stimulus onset asynchrony, but foreshortening effects were not reduced. The results implicate an early, prebottleneck locus for some processes compensating for plane rotation and a subsequent bottleneck or postbottleneck locus for compensation for foreshortening.

Achieving visual object constancy across plane rotation and depth rotation

Visual object constancy is the ability to recognise an object from its image despite variation in the image when the object is viewed from different angles. I describe research which probes the human visual system's ability to achieve object constancy across plane rotation and depth rotation. I focus on the ecologically important case of recognising familiar objects, although the recognition of novel objects is also discussed. Cognitive neuropsychological studies of patients with specific deficits in achieving object constancy are reviewed, in addition to studies which test neurally intact subjects. In certain cases, the recognition of invariant features allows objects to be recognised irrespective of the view depicted, particularly if small, distinctive sets of objects are presented repeatedly. In contrast, in most situations, recognition is sensitive to both the view in-plane and in-depth from which an object is depicted. This result suggests that multiple, view-specific, stored representations of familiar objects are accessed in everyday, entry-level visual recognition, or that transformations such as mental rotation or interpolation are used to transform between retinal images of objects and view-specific, stored representations.

Adult dental visits in California: successes and challenges

OBJECTIVES

This study sought to estimate and characterize the proportion of California adults who visited a dentist in the preceding year and to identify reasons for not going.

METHODS

In 1995, 4,029 adults were interviewed by telephone as part of the California Behavioral Risk Factor Surveillance System. Items included recentness of a dental visit, dental insurance status, and number of teeth lost due to disease. Persons who had not seen a dentist within the preceding year were asked the main reason they had not gone.

RESULTS

In 1995, 65.9% of adults reported visiting a dentist in the preceding twelve months. Use of dental services was greater among persons aged 35 years or older (70.4%) than among those aged 18-34 years (58.4%) and among those with dental insurance (74.9%) than those without (54.4%). Dental visits were less likely among adults living at or below 200 percent of the federal poverty level, those with less than a high school education, and the edentulous. Reasons most commonly cited for not seeing a dentist were no perceived reason to go (37.2%), cost (30.7%), and fear (9.2%).

CONCLUSION

Substantial variation in use of dental services exists among California's adults. Achieving equity in access and opportunity for disease prevention in this state may require expanded dental insurance coverage and serious efforts in oral health promotion.

The effect of prior experience on recognition thresholds for plane-disoriented pictures of familiar objects

We investigated plane rotation effects on the minimum presentation duration that is required in order to recognize pictures of familiar objects, using the method of ascending limits. Subjects made unspeeded verification responses, selecting from 126 written alternatives. Replicating similar identification studies in which brief, masked pictures (Lawson & Jolicoeur, 1998) were presented, disorientation reduced the efficiency of recognition. Mirroring the findings in speeded picture naming studies (e.g., Jolicoeur, 1985; Jolicoeur & Milliken, 1989), but in contrast to those of Lawson and Jolicoeur (1998), orientation effects were found over a wide range of views and were attenuated but not eliminated with experience with a given object. The results bridge the findings from unspeeded verification and speeded naming tasks. They suggest that the same orientation-sensitive processes are tapped in both cases, and that practice effects on these processes are object specific.

Salicylate toxicity masquerading as malignant hyperthermia

We report a case of hyperpyrexia presumed due to topical salicylate toxicity occurring immediately following general anaesthesia for appendicectomy in an eleven year old boy. Some of the features strongly suggested the diagnosis of malignant hyperpyrexia.

View-specific effects of depth rotation and foreshortening on the initial recognition and priming of familiar objects

In a series of three experiments, we examined, first, the effects of viewpoint in depth on the efficiency of initial picture naming and, second, the effects of priming on subsequent naming. On initial presentation, foreshortened views were harder to name than were more typical (nonforeshortened) views. In addition, priming increased as a function of the similarity of the prime and target. Indeed, if a foreshortened view of an object had already been named, the subjects named a subsequent foreshortened view of that object as fast as or faster than they named a subsequent, more typical view. These results provide evidence against theories that predict full view-invariant object recognition and view-invariant priming of object recognition. Instead, the results support theories that suggest that object recognition is mediated by stored representations that are both view- and object-specific.