Large-scale implementation of pooled RNA extraction and RT-PCR for SARS-CoV-2 detection.

INTRODUCTION: Testing for active SARS-CoV-2 infection is a fundamental tool in the public health measures taken to control the COVID-19 pandemic. Because of the overwhelming use of SARS-CoV-2 reverse transcription (RT)-PCR tests worldwide, the availability of test kits has become a major bottleneck and the need to increase testing throughput is rising. We aim to overcome these challenges by pooling samples together, and performing RNA extraction and RT-PCR in pools. METHODS: We tested the efficiency and sensitivity of pooling strategies for RNA extraction and RT-PCR detection of SARS-CoV-2. We tested 184 samples both individually and in pools to estimate the effects of pooling. We further implemented Dorfman pooling with a pool size of eight samples in large-scale clinical tests. RESULTS: We demonstrated pooling strategies that increase testing throughput while maintaining high sensitivity. A comparison of 184 samples tested individually and in pools of eight samples showed that test results were not significantly affected. Implementing the eight-sample Dorfman pooling to test 26 576 samples from asymptomatic individuals, we identified 31 (0.12%) SARS-CoV-2 positive samples, achieving a 7.3-fold increase in throughput. DISCUSSION: Pooling approaches for SARS-CoV-2 testing allow a drastic increase in throughput while maintaining clinical sensitivity. We report the successful large-scale pooled screening of asymptomatic populations.

Safety profile during initiation of propranolol for treatment of infantile haemangiomas in an ambulatory day-care hospitalization setting.

BACKGROUND: Propranolol is the mainstay of treatment for infantile haemangioma. Despite its good safety profile, it is not risk-free. Guidelines for propranolol initiation and monitoring have been suggested, but protocols vary among practitioners. OBJECTIVE: This study sought to assess the prevalence of adverse events and clinically significant fluctuations in haemodynamic parameters in children with infantile haemangioma during initiation of treatment with propranolol in a day-hospitalization setting. METHODS: Children with infantile haemangioma treated with propranolol in a day-hospitalization department of a tertiary paediatric medical centre in 2008-2014 were identified retrospectively. The pretreatment evaluation included clinical examination by a paediatric dermatologist and electrocardiography, echocardiography and clinical examination by a paediatric cardiologist. The propranolol dosage was escalated from 0.5 mg/kg/day to 2 mg/kg/day, divided into three doses/day, over 3 days. Heart rate, blood pressure and blood glucose level were measured before treatment onset and 60 min after the first two doses each day. The third dose was given at home. RESULTS: The cohort included 220 children aged 1 month to 5 years. No severe treatment-related adverse events were documented; 27 patients had minor side-effects. There was a significant decrease in heart rate each day after the first two doses (P < 0.001), and in systolic blood pressure, on day 2 (1 mg/kg/day) after the first dose (P = 0.01). Blood glucose level remained stable. The haemodynamic changes were clinically asymptomatic and did not require intervention. CONCLUSIONS: Propranolol treatment (2 mg/kg/day in three doses) for infantile haemangioma is well tolerated and safe and may be administered and monitored in an ambulatory setting.

Empathy during consoling touch is modulated by mu-rhythm: An EEG study.

The aim of the present study was to examine the mechanisms of empathy for pain that contribute to consoling touch, a distress-alleviating contact behavior carried out by an observer in response to the suffering of a target. We tested romantic couples in a paradigm that involves consoling touch and examined the attenuation of the mu/alpha rhythm (8-13Hz) in the consoling partner. During the task, the toucher either held the consoled partner's right hand (human touch) or held onto the armrest of the chair (non-human touch), while the consoled partner experienced inflicted pain (pain condition) or did not experience any pain (no-pain condition). In accordance with our hypotheses, the results revealed an interaction between touch and pain at in mu/alpha rhythms in all central sites (C3, C4, Cz). Specifically, we found that the toucher's mu suppression was higher in the consoling touch condition, i.e., while touching the partner who is in pain, compared to the three control conditions. Additionally, we found that in the consoling touch condition, mu suppression at electrode C4 of the toucher correlated with a measure of situational empathy. Our findings suggest that electrophysiological and behavioral measures that have been associated with empathy for pain are modulated during consoling touch.

'Virtual lesion' in pain research; a study on magnetic stimulation of the primary motor cortex.

BACKGROUND: 'Virtual lesion' ('VL') is a transient disruption of cortical activity during task performance. It can be induced by single pulses or short trains of transcranial magnetic stimulation (TMS) directed to functionally relevant brain areas. We applied 'VL' methodology of a short train of TMS given on top of experimental tonic pain, expecting to see changes in pain scores. METHODS: Thirty young healthy subjects (15 women) were assessed with active ('VL') or 'sham' TMS in different sessions, randomly. In each session, 30 sec-long contact heat (47.5 °C, right forearm) was applied stand-alone ('baseline') and with 5 sec-long 10 Hz-TMS over left primary motor cortex (M1) starting at 17 sec of the heat stimulation. RESULTS: Pain scores decreased after 'VL' or 'sham' (p < 0.001). Independently of the type of TMS, pain reduction was stronger in women (p = 0.012). A triple Sex x Stimulation type ('VL' or 'sham') x Condition ('baseline' heat pain vs. heat pain with TMS) interaction (p = 0.027) indicated stronger pain reduction by 'VL' in women (p = 0.008) and not in men (p = 0.78) as compared to 'baseline'. Pain catastrophizing and perceived stress ratings affected the model (p = 0.010 and p < 0.001, respectively), but without sex differences. CONCLUSIONS: This study indicates that interactions between cortical excitability of the motor cortex and nociceptive processing may be gender-related.

Ecological aspects of pain in sensory modulation disorder.

BACKGROUND: Sensory Modulation Disorder (SMD) interferes with the daily life participation of otherwise healthy individuals and is characterized by over-, under- or seeking responsiveness to naturally occurring sensory stimuli. Previous laboratory findings indicate pain hyper-sensitivity in SMD individuals suggesting CNS alteration in pain processing and modulation. However, laboratory studies lack ecological validity, and warrant clinical completion in order to elicit a sound understanding of the phenomenon studied. Thus, this study explored the association between sensory modulation and pain in a daily life context in a general population sample. METHODS: Daily life context of pain and sensations were measured in 250 adults (aged 23-40 years; 49.6% males) using 4 self-report questionnaires: Pain Sensitivity Questionnaire (PSQ) and Pain Catastrophizing Scale (PCS) to evaluate the sensory and cognitive aspects of pain; the Sensory Responsiveness Questionnaire (SRQ) to appraise SMD; and the Short Form - 36 Health Survey, version 2 (SF36) to assess health related Quality of Life (QoL). RESULTS: Thirty two individuals (12.8%) were found with over-responsiveness type of SMD, forming the SOR-SMD group. While no group differences (SOR-SMD vs. Non-SMD) were found, low-to-moderate total sample correlations were demonstrated between the SRQ-Aversive sub-scale and i) PSQ total (r=0.31, p<0.01) and sub-scales scores (r=0.27-0.28, p<0.01), as well as ii) PCS total and the sub-scales of Rumination and Helplessness scores (r=0.15, p<0.05). PSQ total and sub-scale scores were more highly correlated with SRQ-Aversive in the SOR-SMD group (r=0.57-0.68, p=0.03-<0.01) compared to Non-SMD group. The Physical Health - Total score (but not the Mental Health - Total) of the SF36 was lower for the SOR-SMD group (p=0.03), mainly due to the difference in the Body pain sub-scale (p=0.04). CONCLUSIONS: Results suggest that SOR-SMD is strongly associated with the sensory aspect of pain but weakly associated with the cognitive aspect. This indicates that SMD co-occurs with daily pain sensitivity, thus reducing QoL, but less with the cognitive-catastrophizing manifestation of pain perception.

Pain experience of adults with intellectual disabilities--caregiver reports.

BACKGROUND: Pain is a problem for individuals with intellectual and developmental disability (IDD), secondary to their impairments, due to invasive medical procedures that these individuals undergo on a regular basis. Current literature indicates pain as a common experience for children with IDD, yet no such reports have been made in regard to adults with IDD. PURPOSES: This study aimed (1) to re-establish the reliability of caregivers as proxy observers; (2) to evaluate the pain experience of adults with IDD by caregivers' proxy report; and (3) to assess the sensitivity of the Non-Communicating Adult Pain Checklist (NCAPC) as a pain scale for chronic pain (CP) in individuals with IDD. METHOD: Frothy-three caregivers, working for more than 3 years with adults with IDD, performed pain assessments of 187 individuals living in a residential facility. Two caregivers evaluated whether each resident suffers from pain and assessed the intensity, causes and duration of pain experience. Furthermore, 52/187 residents [26 with CP and 26 pain free (PF) based on medical record and caregiver reports] were evaluated by an additional seven caregivers using the NCAPC in order to establish the reliability of caregivers as proxy observers. RESULTS: According to caregivers' report, 48% of adults with IDD suffer from pain at a mean level of 6/10, with more than 10% suffering from high levels of pain on a constant basis. Inter-rater agreement was found mostly high with intraclass correlation values ranging between 0.73 and 0.93. Using the NCAPC, we were able to identify CP and PF individuals with a significant score difference (P = 0.003). CONCLUSIONS: The results support the use of the NCAPC as a scale to evaluate CP in adults with IDD. The findings reiterate the reliability of caregivers as proxy observers and the importance of involving them in identifying pain behaviours of their protégées. Our findings reiterate the need for an immediate action for appropriate pain management protocols for adult with IDD.

Temporal and spatial aspects of experimental tonic pain: Understanding pain adaptation and intensification.

BACKGROUND: The underlying mechanisms of adaptations to pain are unclear. In order to explore whether central or peripheral mechanisms predominate, the effects of two centrally mediated phenomena - spatial summation of pain (SSP) and transcutaneous electrical nerve stimulation (TENS) - were examined. The effect of the degree of painfulness, rather than absolute stimulation intensity, was also examined. METHODS: Seventeen participants received several series of individually adjusted tonic noxious-heat stimuli (300 s), inducing an initial perceived pain of 2 (mild pain), 4 (moderate pain) and 6 (strong pain) on a visual analogue scale (VAS). The stimuli were administered to small (2.25 cm2) and large (9 cm2) areas to produce SSP and also during TENS treatment, during which 12 VAS ratings were obtained. RESULTS: Adaptation occurred during VAS-2 stimulation and was minimal, followed by intensification during VAS-4 stimulation, whereas VAS-6 stimulation always induced pain intensification. TENS failed to produce analgesia and SSP did not affect adaptation but affected intensification. Stimulation temperatures affected the magnitude of adaptation and intensification within each degree of painfulness. The mathematical models that best fitted the time trend with VAS-2 and VAS-4 were linear, whereas a power function best fitted VAS-6 stimulation. CONCLUSIONS: The mathematical models and the lack of effect of SSP on adaptation suggest that its dominant component is peripheral. Whereas relative painfulness determines whether pain adaptation or intensification occurs (probably a defence mechanism), absolute stimulation intensities influence the magnitude of the effect. Pain intensification is differentially affected by probe size, depending upon the occurrence of initial adaptation.

Atypical central pain processing in sensory modulation disorder: absence of temporal summation and higher after-sensation.

Sensory over-responsivity (SOR), a subtype of the proposed sensory modulation disorder (SMD), is characterized by over-responsiveness to stimuli in several sensory modalities. SMD individuals demonstrate abnormal responses to naturally occurring stimuli in a manner that interferes with daily life participation. Previous psychophysical testing of the somatosensory system revealed that SOR individuals rated pain sensations higher than controls, demonstrating hyperalgesia that can be centrally mediated. Temporal summation (TS) of second pain and after-sensation are manifestations of central sensitization; therefore, this study explored these measures for better characterization of central pain processing in SOR. Twelve SOR adults and 12 healthy controls participated. TS was produced by a train of fifteen repetitive heat pulses, 0.7 s duration each, and 2 s of inter-stimulus interval, applied to the thenar-eminence, while four pain ratings were obtained. An after-sensation was then measured for 5 min, obtaining six pain ratings. No TS of pain was indicated in the SOR group (SOR: p = 0.36; control: p < 0.001). Further, while controls reported a gradual disappearance of pain after-sensation, individuals with SOR continued to report pain for the duration of the 5 min measured (p = 0.002). These results demonstrate an atypical response pattern, suggesting alteration in pain processing and/or modulation at a central level in individuals with SOR. These possible neural changes may manifest themselves as interference with daily functioning as well as shed light on some of the between-subject variability seen in psychophysical testing in non-painful subjects.

The effect of post-surgical neuroplasticity on the stability of systemic pain perception: a psychophysical study.

BACKGROUND: Surgery-induced neuroplasticity at spinal and supra-spinal levels is assumed to evoke a clinical acute post-operative pain (cAPOP) experience, which is expressed by allodynia and/or hyperalgesia. It remains unclear whether the systemic pain perception measured outside the incision area remains unchanged and whether it is affected by the presence of cAPOP. AIMS: This study explored whether the systemic perception of experimental pain would be altered towards hypersensitivity following elective gynecological surgery unmasked by opioids. METHODS: A perioperative psychophysical evaluation of heat pain thresholds (HPT) and pain estimations were obtained in a remote bodily area before and after surgery among 35 women. RESULTS: The ratings for both pain dimensions of intensity and unpleasantness remained stable following surgery. However, there was a reduction found in HPT the day after surgery (43.6 ± 2.2 °C to 42.2 ± 3.1 °C, p = 0.002). This reduction was associated with lower HPT measured before surgery (r = .56, p < 0.000) and with higher cAPOP intensity obtained at rest (r = -.44, p = 0.008). CONCLUSIONS: This post-surgical allodynia, as reflected by the systemic enhancement of pain perception, may represent plasticity in the central pain pathways at the supra-spinal level. Pre-surgical assessment of a patient's pain perception profile may predict certain pain dimensions of post-surgical pain plasticity. The evaluation of individual pain profiles may contribute to a mechanism-based approach aimed to attenuate the cAPOP.

Abnormal cortical activity in patients with temporomandibular disorder evoked by cognitive and emotional tasks.

Patients with temporomandibular disorder (TMD) perform poorly in neuropsychological tests of cognitive function. These deficits might be related to dysfunction in brain networks that support pain and cognition, due to the impact of chronic pain and its related emotional processes on cognitive ability. We therefore tested whether patients with TMD perform poorly in cognitive and emotion tasks and whether they had abnormal task-evoked brain activity. Seventeen female subjects with nontraumatic TMD and 17 age-matched healthy female subjects underwent functional magnetic resonance imaging while performing counting Stroop tasks comprising neutral words, incongruent numbers, or emotional words, including TMD-specific words. Group differences in task-related brain responses were assessed. Connectivity between 2 pairs of coupled brain regions during the cognitive and emotional tasks (prefrontal-cingulate and amygdala-cingulate) was also examined. The patients had sluggish Stroop reaction times for all Stroop tasks. Furthermore, compared to controls, patients showed increased task-evoked responses in brain areas implicated in attention (eg, lateral prefrontal, inferior parietal), emotional processes (eg, amygdala, pregenual anterior cingulate), motor planning and performance (eg, supplementary and primary motor areas), and activation of the default-mode network (medial prefrontal and posterior cingulate). The patients also exhibited decoupling of the normally correlated activity between the prefrontal and cingulate cortices and between the amygdala and cingulate cortex. These findings suggest that the slow behavioral responses in idiopathic TMD may be due to attenuated, slower, and/or unsynchronized recruitment of attention/cognition processing areas. These abnormalities may be due to the salience of chronic pain, which inherently requires attention. Sluggish performance in cognitive and emotional interference tasks in patients with nontraumatic temporomandibular disorder is associated with pronounced and unsynchronized task-evoked fMRI brain responses.

[Constant endocardiac stimulation of the heart ventricles controlled by atrial biopotential]. / Postoiannaia endokardial'naia stimuliatsiia zheludochkov serdtsa, upravliaemaia biopotentsialom predserdiia

The technique procedures and the first clinical experience of the atrial biopotential controlled endocardiac electric stimulation of the ventricles applied to 14 patients 17 to 72 years old with complete or intermittent atrio-ventricular block and attacks of Morgagni-Adams-Stocks disease are described. An endocardial detector electrode designed by German scientists was used to take biopotentials of the atrium. The stimulation proved successful in all the patients who were kept under observations for a period from 1 to 30 months. Advantages of the method under review are set forth.