Megalencephaly secondary to a novel germline missense variant p.Asp322Tyr in AKT3 associated with growth hormone deficiency and central hypothyroidism: A case report

Germline gain of function variations in the AKT3 gene cause brain overgrowth syndrome with megalencephaly and diffuse bilateral cortical malformations. Here we report a child with megalencephaly, who is a carrier of a novel heterozygous missense variant in the AKT3 gene NM_005465.7:c.964G>T,p.Asp322Tyr. The phenotype of this patient is associated with pituitary deficiencies diagnosed at 2 years of age: growth hormone (GH) deficiency responsible for growth delay and central hypothyroidism. After 6 months of GH treatment, intracranial hypertension was noted, confirmed by the observation of papilledema and increased intracranial pressure, requiring the initiation of acetazolamide treatment and the discontinuation of GH treatment. This is the second reported patient described with megalencephaly and AKT3 gene variant associated with GH deficiency . Other endocrine disorders have also been reported in few cases with hypothyroidism and hypoglycemia. Pituitary deficiency may be a part of the of megalencephaly phenotype secondary to germline variant in the AKT3 gene. Special attention should be paid to growth in these patients and search for endocrine deficiency is necessary in case of growth retardation or hypoglycemia.

Childhood-Onset Lupus Nephritis in the Childhood Arthritis and Rheumatology Research Alliance Registry: Short-Term Kidney Status and Variation in Care

OBJECTIVE

The goal was to characterize short-term kidney status and describe variation in early care utilization in a multicenter cohort of patients with childhood-onset systemic lupus erythematosus (cSLE) and nephritis.

METHODS

We analyzed previously collected prospective data from North American patients with cSLE with kidney biopsy-proven nephritis enrolled in the Childhood Arthritis and Rheumatology Research Alliance (CARRA) Registry from March 2017 through December 2019. We determined the proportion of patients with abnormal kidney status at the most recent registry visit and applied generalized linear mixed models to identify associated factors. We also calculated frequency of medication use, both during induction and ever recorded.

RESULTS

We identified 222 patients with kidney biopsy-proven nephritis, with 64% class III/IV nephritis on initial biopsy. At the most recent registry visit at median (interquartile range) of 17 (8-29) months from initial kidney biopsy, 58 of 106 patients (55%) with available data had abnormal kidney status. This finding was associated with male sex (odds ratio [OR] 3.88, 95% confidence interval [95% CI] 1.21-12.46) and age at cSLE diagnosis (OR 1.23, 95% CI 1.01-1.49). Patients with class IV nephritis were more likely than class III to receive cyclophosphamide and rituximab during induction. There was substantial variation in mycophenolate, cyclophosphamide, and rituximab ever use patterns across rheumatology centers.

CONCLUSION

In this cohort with predominately class III/IV nephritis, male sex and older age at cSLE diagnosis were associated with abnormal short-term kidney status. We also observed substantial variation in contemporary medication use for pediatric lupus nephritis between pediatric rheumatology centers. Additional studies are needed to better understand the impact of this variation on long-term kidney outcomes.

Diagnosis of vascular parkinsonism: A new tool for gait hypokinesia occurring in older persons

INTRODUCTION

Reliable diagnosis of vascular parkinsonism (VaP) in the presence of a gait hypokinesia is an issue that is encountered in geriatrics. The EVAMAR-AGEX study was focusing on the phenomenon of recurrent falls in older persons (OP) with this parkinsonian gait. The present study is focusing on the diagnosis of VaP-related parkinsonian gait by developing a diagnostic guidance model adapted to OP.

METHODS

Data from baseline and the 2-year follow-up visit were used to carry out univariate analysis and calculation of odds ratios, allowing to identify relevant variables to include in the diagnostic guidance model. To evaluate the model, confusion matrices were created, evaluating true positive, false negative, false positive and true negative incidences, sensitivity and specificity, and negative and positive predictive values.

RESULTS

79 patients included 58% male; average age 81.24 years. VaP diagnosis according to Zijlmans criteria occurred in 28%; neurodegenerative parkinsonian syndromes in 72%. A 4-criteria model was established to facilitate diagnostic: lack of prior hallucinations, lack of movement disorders tremor excluded, no cognitive fluctuations, and ≥75 years of age at diagnosis. In combination of 4/4 criteria, all of them were required to disclose a specificity of 91% in the diagnosis of VaP. In combination of 3/4, in case of negative test, a negative predictive value for VaP diagnosis of 0.97 was obtained.

CONCLUSION

The challenge of our tool is both to be able to rule out what is probably not a VaP and to argue what makes a VaP diagnosis probable in OP.

Spatio-Temporal Gait Parameters of Hospitalized Older Patients: Comparison of Fallers and Non-Fallers

Gait disorders are predisposing factors for falls. They are accessible to rehabilitation and can be analyzed using tools that collect spatio-temporal parameters of walking, such as the GAITRite^® mat. The objective of this retrospective study was to find differences between the spatio-temporal parameters in patients who had fallen compared to patients who did not fall in a population of older patients hospitalized in acute geriatrics department. Patients over 75 years were included. For each patient, spatio-temporal parameters were collected using the GAITRite^® mat. The patients were divided into two groups according to whether they had a history of fall. The spatio-temporal parameters were compared between the two groups and in relation to the general population. Sixty-seven patients, with an average age of 85.9 ± 6 years, were included. The patients had comorbidities, cognitive impairment and were polymedicated. The mean walking speed was 51.4 cm/s in non-fallers group and 47.3 cm/s in fallers group (p = 0.539), indicating pathological walking in comparison with the general population of the same age (average 100 cm/s). No association was found between the spatio-temporal parameters and fall, probably linked to many confounding factors such as the pathogenicity of walking of our patients and their comorbidities.

Intraarticular steroids as DMARD-sparing agents for juvenile idiopathic arthritis flares: Analysis of the Childhood Arthritis and Rheumatology Research Alliance Registry

BACKGROUND

Children with juvenile idiopathic arthritis (JIA) who achieve a drug free remission often experience a flare of their disease requiring either intraarticular steroids (IAS) or systemic treatment with disease modifying anti-rheumatic drugs (DMARDs). IAS offer an opportunity to recapture disease control and avoid exposure to side effects from systemic immunosuppression. We examined a cohort of patients treated with IAS after drug free remission and report the probability of restarting systemic treatment within 12 months.

METHODS

We analyzed a cohort of patients from the Childhood Arthritis and Rheumatology Research Alliance (CARRA) Registry who received IAS for a flare after a period of drug free remission. Historical factors and clinical characteristics and of the patients including data obtained at the time of treatment were analyzed.

RESULTS

We identified 46 patients who met the inclusion criteria. Of those with follow up data available 49% had restarted systemic treatment 6 months after IAS injection and 70% had restarted systemic treatment at 12 months. The proportion of patients with prior use of a biologic DMARD was the only factor that differed between patients who restarted systemic treatment those who did not, both at 6 months (79% vs 35%, p < 0.01) and 12 months (81% vs 33%, p < 0.05).

CONCLUSION

While IAS are an option for all patients who flare after drug free remission, it may not prevent the need to restart systemic treatment. Prior use of a biologic DMARD may predict lack of success for IAS. Those who previously received methotrexate only, on the other hand, are excellent candidates for IAS.

Abnormal liver tests and non-alcoholic fatty liver disease predict disease progression and outcome of patients with COVID-19

BACKGROUND AND AIMS

Coronavirus disease 2019 (COVID-19) is a serious public health issue that became rapidly pandemic. Liver injury and comorbidities, including metabolic syndrome, are associated with severe forms of the disease. This study sought to investigate liver injury, clinical features, and risk factors in patients with mild, moderate, and severe COVID-19.

METHODS

We retrospectively included all consecutive patients hospitalized with laboratory-confirmed COVID-19 between February, 22 and May 15, 2020 at the emergency rooms of a French tertiary hospital. Medical history, symptoms, biological and imaging data were collected.

RESULTS

Among the 1381 hospitalizations for COVID-19, 719 patients underwent liver tests on admission and 496 (68.9%) patients displayed abnormal liver tests. Aspartate aminotransferase was most commonly abnormal in 57% of cases, followed by gamma-glutamyl transferase, alanine aminotransferase, albumin, alkaline phosphatase, and total bilirubin in 56.5%, 35.9%, 18.4%, 11.4%, and 5.8%. The presence of hepatocellular type more than 2xULN was associated with a higher risk of hospitalization and a worse course of severe disease (odd ratio [OR] 5.599; 95%CI: 1.27-23.86; p = 0.021; OR 3.404; 95% CI: 2.12-5.47; p < 0.001, respectively). A higher NAFLD fibrosis score was associated with a higher risk of hospitalization (OR 1.754; 95%CI: 1.27-2.43, p < 0.001). In multivariate analyses, patients with high fibrosis-4 index had a 3-fold greater risk of severe disease (p < 0.001).

CONCLUSION

Abnormal liver tests are common in patients with COVID-19 and could predict the outcome. Patients with non-alcoholic fatty liver disease and liver fibrosis are at higher risk of progressing to severe COVID-19.

Humoral immune response after COVID-19 infection or BNT162b2 vaccine among older adults: evolution over time and protective thresholds

The objectives of this study were to assess the dynamics of the SARS-CoV-2 anti-RBD-IgG response over time among older people after COVID-19 infection or vaccination and its comparison with indicative levels of protection. Geriatric patients with SARS-CoV-2 serological test results were included and divided into three groups. A vaccine group (n = 34), a group of natural COVID-19 infection (n = 32), and a group who contracted COVID-19 less than 15 days after the first injection (n = 17). Eighty-three patients were included; the median age with IQR was 87 (81–91) years. In the vaccine group at 1 month since the first vaccination, the median titer of anti-RBD-IgG was 620 (217–1874) BAU/ml with 87% of patients above the theoretical protective threshold of 141 BAU/ml according to Dimeglio et al. (J Infec. 84(2):248–88, [7]). Seven months after the first vaccination, this titer decreased to 30 (19–58) BAU/ml with 9.5% of patients > 141 BAU/ml. In the natural COVID-19 infection group, at 1 month since the date of first symptom onset, the median titer was 798 (325–1320) BAU/ml with 86.7% of patients > 141 BAU/ml and fell to 88 (37–385) with 42.9% of patients > 141 BAU/ml at 2 months. The natural infection group was vaccinated 3 months after the infection. Five months after the vaccination cycle, the median titer was 2048 (471–4386) BAU/ml with 83.3% of patients > 141 BAU/ml. This supports the clinical results describing the decrease in vaccine protection over time and suggests that vaccination after infection can maintain significantly higher antibody titer levels for a prolonged period of time.

Open-source deep learning-based air-voids detection algorithm for concrete microscopic images

Analyzing concrete microscopic images is difficult because of its highly heterogeneous composition and the different scales involved. This article presents an open-source deep learning-based algorithm dedicated to air-void detection in concrete microscopic images. The model, whose strategy is presented alongside concrete compositions information, is built using the Mask R-CNN model. Model performances are then discussed and compared to the manual air-void enhancement technique. Finally, the selected open-source strategy is exposed. Overall, the model shows a good precision (mAP = 0.6452), and the predicted air void percentage agrees with experimental measurements highlighting the model's potential to assess concrete durability in the future. This article is protected by copyright. All rights reserved.

Social determinants of health influence disease activity and functional disability in Polyarticular Juvenile Idiopathic Arthritis

BACKGROUND

Social determinants of health (SDH) greatly influence outcomes during the first year of treatment in rheumatoid arthritis, a disease similar to polyarticular juvenile idiopathic arthritis (pJIA). We investigated the correlation of community poverty level and other SDH with the persistence of moderate to severe disease activity and functional disability over the first year of treatment in pJIA patients enrolled in the Childhood Arthritis and Rheumatology Research Alliance Registry.

METHODS

In this cohort study, unadjusted and adjusted generalized linear mixed effects models analyzed the effect of community poverty and other SDH on disease activity, using the clinical Juvenile Arthritis Disease Activity Score-10, and disability, using the Child Health Assessment Questionnaire, measured at baseline, 6, and 12 months.

RESULTS

One thousand six hundred eighty-four patients were identified. High community poverty (≥20% living below the federal poverty level) was associated with increased odds of functional disability (OR 1.82, 95% CI 1.28-2.60) but was not statistically significant after adjustment (aOR 1.23, 95% CI 0.81-1.86) and was not associated with increased disease activity. Non-white race/ethnicity was associated with higher disease activity (aOR 2.48, 95% CI: 1.41-4.36). Lower self-reported household income was associated with higher disease activity and persistent functional disability. Public insurance (aOR 1.56, 95% CI 1.06-2.29) and low family education (aOR 1.89, 95% CI 1.14-3.12) was associated with persistent functional disability.

CONCLUSION

High community poverty level was associated with persistent functional disability in unadjusted analysis but not with persistent moderate to high disease activity. Race/ethnicity and other SDH were associated with persistent disease activity and functional disability.

Older Persons Displaying Parkinsonian Gait: Prediction and Explanation of the Recurrent Falling Phenomenon and Its Related Poor Prognosis

INTRODUCTION

Parkinsonian gait in older persons is a major risk factor for recurrent falling. This prospective, longitudinal study (named EVAMAR-AGEX) aimed to validate the threshold value of two or more falls per year for distinguishing non-recurrent (NRF) from recurrent fallers (RF), to explore predictive factors for recurrent falling, and to identify factors which underlie the transition of patients from NRF to RF. The study took place over 2 years, with an intermediate analysis at 1 year of follow-up. Herein, we report results after 2 years of follow-up.

METHODS

Participants over the age of 65, diagnosed with parkinsonian gait, were followed over the course of 2 years. Induced parkinsonian syndrome and uncontrolled orthostatic hypotension were excluded. Assessments of motor, visual, and cognitive functions were carried out during visits at baseline. Between visits at 12 and 24 months of follow-up, data were collected by phone call every 2 months (falls, traumatic falls, hospitalizations, cognitive fluctuations, delirium, and mortality). Odds ratios (ORs) for a panel of predictive factors for recurrent falling were established using a Bayesian model.

RESULTS

Sixty-six of the 79 initially enrolled participants progressed to the second year of the study, with a mean age of 80.57 (SD 6.3), 56% male, presenting parkinsonian gait (53% Parkinson's disease, 15% atypical neurodegenerative parkinsonism, 21% vascular parkinsonism, and 11% diffuse Lewy body disease). At 2 years of follow-up, 67% were RF. Univariate analysis revealed a previous history of falls to be the most significant predictive factor of recurrent falls (OR 13.16, credibility interval [CrI] [95%] 4.04-53.73), and this was reinforced at 2 years of follow-up compared to the intermediate 1-year analysis (OR 11.73, CrI [95%] 4.33-35.28). Multivariate analysis confirmed a previous history of falls (OR 13.20, CrI [95%] 3.29-72.08) and abnormal posture (OR 3.59, CrI [95%] 1.37-11.26) to be predictive factors for recurrent falling. Cognitive decline and fluctuating cognition were associated with the transition from NRF to RF (-3.5 MMSE points for participants transitioning from NRF to RF).

CONCLUSION

Within this population of older persons presenting parkinsonian gait, a previous history of falls and abnormal posture may be used to easily identify individuals at risk of recurrent falls. Cognitive decline and fluctuations may underlie the transition of NRF to RF.

Therapeutic prevention of COVID-19 in elderly: a case-control study

COVID-19 is a particularly aggressive disease for the elderly as 86% of deaths related to COVID-19 occur in people over 65 years of age. Despite the urgent need for a preventive treatment, there are currently no serious leads, other than the vaccination. The aim of this retrospective case-control study is to find a pharmacological preventive treatment of COVID-19 in elderly patients. One-hundred-seventy-nine patients had been in contact with other COVID-19 patients at home or in hospital, of whom 89 had tested RT-PCR-positive (COVID-pos) for the virus and 90 had tested RT-PCR-negative (COVID-neg). Treatments within 15 days prior to RT-PCR (including antihypertensive drugs, antipsychotics, antibiotics, nonsteroidal anti-inflammatory drugs, proton pump inhibitors (PPIs), oral antidiabetics (OADs), corticosteroids, immunosuppressants), comorbidities, symptoms, laboratory values, and clinical outcome were all collected. COVID-pos patients more frequently had a history of diabetes (P = .016) and alcoholism (P = .023), a lower leukocyte count (P = .014) and a higher mortality rate - 29.2% versus 14.4% - (P = .014) when compared to COVID-neg patients. Patients on PPIs were 2.3 times less likely (odds ratio [OR] = 0.4381, 95% confidence interval [CI] [0.2331, 0.8175], P = .0053) to develop COVID-19 infection, compared to those not on PPIs. No other treatment decreased or increased this risk. COVID-pos patients on antipsychotics (P = .0013) and OADs (P = .0153), particularly metformin (P = .0237), were less likely to die. Thus, patients on treatment with PPI were less likely to develop COVID-19 infection, and those on antipsychotics or metformin had a lower risk of mortality. However, prospective studies, including clinical trials, are needed to confirm or not these findings.

Presence of active myocarditis at the 6 month follow-up appointment for a severe form of COVID-19: a case report

Here, we present the case of an 81‐year‐old male patient, who was hospitalized for a severe form of COVID‐19. Transthoracic echocardiogram (TTE) performed 1 month after symptom onset was normal. Respiratory evolution was favourable, and the patient was discharged at Day 78. At 6 months, despite a good functional recovery, he presented pulmonary sequelae, and the TTE revealed a clear reduction of left ventricular ejection fraction (LVEF) and mild LV dilatation without cardiac symptoms. The cardiac magnetic resonance (CMR) using Lake Louise Criteria (LLC), T1 and T2 mapping showed focal infero‐basal LV wall oedema, elevated T1 and T2 myocardial relaxation times especially in basal inferior and infero‐lateral LV walls, and sub‐epicardial late gadolinium enhancement in those LV walls. The diagnosis of active myocarditis was raised especially based on TTE abnormalities and CMR LLC, T1 and T2 mapping. Currently, we are not aware of published reports of a 6 month post‐COVID‐19 active myocarditis.

Suplementação de butirato de sódio e os efeitos nos níveis de glicose e no metabolismo lipídico de vacas leiteiras

O objetivo desse estudo foi avaliar os efeitos da suplementação com butirato de sódio nos níveis de glicose plasmática e no metabolismo lipídico de vacas no meio da lactação. Para isso, foram utilizadas 10 vacas (4 da raça Holandês e 6 da raça Jersey), multíparas, com 150 dias em lactação (DEL) e aleatoriamente divididas em 2 grupos: Grupo Controle (GC, n = %), que recebeu uma dieta padrão; Grupo Tratamento (GT, n = 5), que recebeu a dieta padrão mais 1,0g/kg de peso vivo por dia de butirato de sódio por um periodo de 8 dias. Amostras individuais de sangue foram coletadas diariamente durante o periodo experimental para análise de β-hidroxibutirato (BHB), ácidos graxos não esterificados (AGNE), triglicerídeos, colesterol e glicose. Pode ser observado que no GT os níveis de BHB plasmático foi maior (0,64 ± 0,03 mmol/l e 0,91 ± 0,03 mmol/l, para GC e GT, respectivamente, P = 0.001) e os níveis de glicose foram mais baixos que o GC (55,5 ± 0,84 mg/dL e 51,1 ± 0,75 mg/dL, para GT e GC, respectivamente, P < 0.0001). Esses resultados mostram que a suplementação de vacas com butirato de sódio pode regular a taxa de lipólise e as concentrações de AGNE, melhorando o estado de saúde do animal.

Gait Disorder among Elderly People, Psychomotor Disadaptation Syndrome: Post-Fall Syndrome, Risk Factors and Follow-Up - A Cohort Study of 70 Patients

INTRODUCTION

Falls among older people are a major health issue and the first cause of accidental death after 75 years of age. Post-fall syndrome (PFS) is commonly known and yet poorly studied.

OBJECTIVE

Identify risk factors for PFS and do a follow-up 1 year later.

METHODS

We included all patients over 70 years of age hospitalized after suffering a fall in a case-control study, and then followed them in a cohort study. PFS was retained in case of functional mobility decline (transferring, walking) occurring following a fall in the absence of an acute neurological, orthopedic or rheumatic pathology directly responsible for the decline. The data initially collected were: clinical (anamnestic, emergency and departmental/ward evolution, medical history, lifestyle, treatments, clinical examination items); and imaging if the patient had been subjected to brain imaging in the last 3 years prior to inclusion. Regarding the follow-up at 1 year, we collected from the general physician the occurrence and the characteristics of new falls, functional mobility assessment, hospitalization and death.

RESULTS

Inclusion took place from March 29, 2016 to June 7, 2016 and follow-up until June 30, 2017. We included 70 patients. A total of 29 patients exhibited a PFS (41.4 %). Risk factors for PFS included age, walking disorder prior to the fall, the use of a walking aid prior to the fall, no unaccompanied outdoor walk in the week before the fall, visual impairment making close reading impossible, stiffness in ankle dorsiflexion, grip strength and the fear of falling. Among patients with PFS, 52.9% could still perform a transfer at 1 year and 64.7% could still walk against 80.7% and 85.2%, respectively, for patients without PFS.

CONCLUSION

The study showed the existence of body functions/structure impairments and activity limitations prior to the fall among patients exhibiting a PFS. This suggests the existence of a pre-fall syndrome, i.e., a psychomotor disadaptation syndrome existing prior to the fall. Among the 8 risk factors, fear of falling, vision impairment and muscle strength could be targeted for improvement. The diagnosis of PFS could be a marker of loss of functional mobility at 1 year.

Parkinsonian gait in elderly people: Significance of the threshold value of two and more falls per year

OBJECTIVES

Parkinsonism in the elderly presents a major risk factor for recurrent falls (2 and more falls per year), which is associated with increased morbidity. The main objective was to investigate explanatory variables relating to the risk of being recurrent fallers (RF) in persons with parkinsonian gait.

METHODS

Seventy-nine among 172 eligible persons were enrolled in this prospective study, the findings of which were analyzed at 12 months. Motor and non-motor features, as well as follow-up interviews to identify falls, loss of ability to walk, fluctuating cognition, traumatic falls, all-cause hospitalizations and deaths were collated and results compared between non RF (zero and one fall per year) and RF. Bayesian model averaging was used to predict the probability of patients being RF from their medical history as well as from cognitive assessment, gait velocity, vision and posture.

RESULTS

N=79, 0.58 men, 50% had Parkinson's disease, 14% other neurodegenerative parkinsonian syndrome, 23% vascular parkinsonism and 13% Lewy body disease, 58% were RF. Median age 81.2 years and median MMSE 25/30. A history of falls and of hallucinations, median odds ratio respectively 9.06 (CI 2.34-38.22), 4.21 (CI 1.04-18.67) were associated with the highest odds ratios along with fluctuating cognition and abnormal posture. Two or more falls a year was a relevant threshold to distinguish a population with a high risk of comorbidity.

CONCLUSION

The whole history of falls, hallucinations and fluctuating cognition can be considered predictive of recurrent falls in elderly people with parkinsonian gait and provide a tracking tool for patient management.

Influência da restrição alimentar e do estresse térmico sobre parâmetros fisiológicos em ovinos

RESUMO Objetivou-se avaliar as alterações fisiológicas de ovinos submetidos à restrição alimentar, expostos à radiação solar e à sombra. Dez borregas mestiças foram divididas igualmente em dois grupos: grupo radiação solar - GRS, animais expostos ao sol durante o dia; e grupo sombra - GS, animais alocados dentro de um galpão à sombra. Nos seis dias iniciais de experimento, os animais foram submetidos à restrição alimentar, com acesso apenas à água, já expostos ao sol ou à sombra. Nos seis dias subsequentes, foi ofertada dieta composta por ração e feno de alfafa (3%PV). Os parâmetros avaliados foram frequência respiratória (FR), temperatura retal (TR), β-hidroxibutirato (BHB), pH urinário, ingestão de matéria seca (IMS) e dados bioclimáticos (temperatura, umidade relativa do ar e índice de temperatura e umidade - ITU). A FR foi o parâmetro em que houve maior diferença significativa entre os grupos (p<0,05). O balanço energético negativo foi constatado em todos os animais (BHB>0,8mmol/L; pH<7,0). Ovelhas que sofrem restrição alimentar durante períodos de alta temperatura e umidade têm menor frequência respiratória e temperatura interna, independentemente de estar na sombra ou pleno sol. Porém, quando normalizado a oferta de alimento as ovelhas em pleno sol têm menor ingestão de matéria seca.

The occurrence of diseases and their relationship with passive immune transfer in Holstein dairy calves submitted to individual management in southern Brazil

ABSTRACT Calves are extremely dependent on colostrum intake for the acquisition of passive immunity. This study aimed to determine the occurrence of diarrhea and respiratory diseases and the impact of Failure of Passive Immune Transfer (FPIT) on the health and zootechnical performance of Holstein dairy calves in individual management. This study has been carried out in five commercial farms in Rio Grande do Sul State, Brazil, from March 2017 to January 2018. In this study, 131 calves were followed from birth to 60 days of age. Total Plasmatic Protein (TPP) has been performed to determine passive immune transfer quality in 53 calves (53/131). A daily clinical follow-up has been accomplished aiming at diagnosing diseases and their incidences, and zootechnical measures such as withers height, width of the croup and weight have been evaluated. FPIT rate was 32.07%, diarrhea occurrence and respiratory diseases were 77.9% and 49.6%, respectively. FPIT increased the chances of calves presenting diarrhea and developing respiratory diseases, but no differences on zootechnical performance were found. The frequency of FPIT is still high and is a factor that corroborated the increased risk for diarrhea and respiratory disease but did not influence the performance of calves in the preweaning phase.

Effects of timing of artificial insemination and treatment of semen with a Slo3 potassium channel blocker on fertility of dairy heifers subjected to the 5-day CIDR-Synch protocol

Two experiments were conducted to evaluate the effects of the timing of artificial insemination (AI) and incorporation of the Slo3 K⁺ channel blocker 4-(4-chlorophenyl)butyl-diethyl-heptylammonium to semen extender (CSE) on pregnancy per AI (P/AI) and pregnancy loss in dairy heifers. In experiment 1, Holstein heifers were subjected to the 5-d CIDR-Synch protocol: d -8 GnRH and controlled internal drug-release device (CIDR); d -3 PGF_2α and CIDR removal; d -2 PGF_2α; d 0 GnRH) and assigned randomly to receive timed AI with control semen on d 0 (72-CON; n = 104), control semen on d -1 (48-CON; n = 100), or CSE-treated semen on d -1 (48-CSE; n = 98). Heifers were fitted with collar-mounted automated estrus detection devices to monitor physical activity and rumination. In experiment 2, Holstein heifers were subjected to the 5-d CIDR-Synch protocol and received a mount detection patch at the first PGF_2α injection. Heifers detected in estrus before d 0 were inseminated on the same day, whereas those not detected in estrus received the second GnRH injection and timed AI on d 0. Heifers were assigned randomly to receive AI with control (AI-CON; n = 148) or CSE-treated semen (AI-CSE; n = 110). Four bulls with proven fertility were used in both experiments, and ejaculates from each sire were divided and processed as CON or CSE. Pregnancy was diagnosed by transrectal ultrasonography at 29 and 54 d after AI. Data were analyzed by logistic regression, and statistical models included the fixed effects of treatment and enrollment week. In experiment 1, orthogonal contrasts were built to assess the effects of day of AI (72-CON vs. 48-CON + 48-CSE) and treatment of semen with CSE (48-CON vs. 48-CSE). Pregnancy per AI on d 29 (72-CON = 60.8, 48-CON = 35.2, 48-CSE = 39.8%) and d 54 (72-CON = 58.2, 48-CON = 31.6, 48-CSE = 36.2%) was greater for heifers inseminated on d 0 compared with d -1. However, no effect of semen extender on P/AI was observed in heifers inseminated on d -1. In experiment 2, P/AI tended to be greater for AI-CSE than for AI-CON on d 29 (58.6 vs. 47.3%) and d 54 after AI (55.6 vs. 43.7%). Advancing AI by 24 h decreased the likelihood of pregnancy, and use of CSE was unable to overcome the expected asynchrony between insemination and ovulation. Nevertheless, incorporation of CSE in semen processing tended to improve P/AI when heifers received AI upon detected estrus or timed AI concurrently with the final GnRH of the 5-d CIDR-Synch protocol.

Effect of high-intensity interval training and continuous endurance training on peak oxygen uptake among seniors aged 65 or older: A meta-analysis of randomized controlled trials

BACKGROUND

Ageing is intrinsically associated with a progressive decline in cardiorespiratory fitness (CRF) as measured by peak oxygen uptake (VO_2peak ). Improving CRF through physical activity contribute to better and healthy ageing. High-intensity interval training (HIIT) is a potent method of improving CRF among seniors, yet comparisons between this type of training and traditional endurance training (ET) are equivocal especially among older adults.

PURPOSE

To analyse the effects of HIIT and ET on the VO_2peak of seniors aged 65 years or older when compared with controls and also when the two types of training were compared with one another.

METHODS

A comprehensive, systematic database search for manuscripts was performed in Embase, Medline, PubMed Central, ScienceDirect, Scopus and Web of Science using key words. Two reviewers independently assessed interventional studies for potential inclusion. Fifteen randomized controlled trials (RCTs) were included totalling 480 seniors aged 65 years or over. Across the trials, no high risk of bias was measured.

RESULTS

In pooled analysis of the RCTs, the VO_2peak was significantly higher after ET sessions compared with controls (mean difference-MD = 1.35; 95% confidence interval-CI: 0.73-1.96). Furthermore, VO_2peak was found significantly higher not only when compared HIIT with controls (MD = 4.61; 95% CI: 3.21-6.01), but also when compared HIIT with ET (MD = 3.76; 95% CI: 2.96-4.56).

CONCLUSION

High-intensity interval training and ET both elicit large improvements in the VO_2peak of older adults aged 65 or over. When compared with ET, the gain in VO_2peak was greater following HIIT. Nevertheless, further RCTs are therefore needed to confirm our results in senior's population.

Altered rumen fermentation patterns in lactating dairy cows supplemented with phytochemicals improve milk production and efficiency

Tannins and other phytochemicals are known to improve RUP in the diet by binding protein and then limiting ruminal degradation, which may improve milk yield and milk protein synthesis. The objective of this study was to evaluate the effects of dietary phytochemicals (tannins and Capsicum species) as rumen modifiers on production parameters and milk efficiency in dairy cows. Twenty-four multiparous Holstein cows (96 ± 16 d in milk; mean ± standard deviation) were used in a replicated 3 × 3 Latin square design balanced to measure carryover effects. Cows were blocked according to days in milk, milk production, and body weight and randomly assigned to 1 of 3 groups (n = 8/group). Each group was assigned to a unique treatment sequence across the 3 periods in the Latin square. The experiment consisted of a 14-d covariate period and three 30-d treatment periods. Cows received a basal diet supplemented with soybean meal pellets (SB) as the control diet, phytochemicals (RUM; Rumiviv, CCPA, Janzé, France) pelleted with soybean meal, or expeller soybean meal (ESBM; SoyPlus, West Central Soy, Ralston, IA). Milk production and dry matter intake during the last 4 d of each period were used for statistical analysis. Blood and rumen fluid samples were collected on d 27 of each period. Rumen fluid was analyzed for ammonia N and volatile fatty acids as well as ruminal bacteria via quantitative PCR amplification of 16S ribosomal DNA genes. Greater milk yield (37.9 vs. 36 kg/d), energy-corrected milk (39.7 vs 37.1 kg/d), and protein yield (1.15 vs. 1.08 kg/d) were observed in RUM compared with SB, but these parameters were similar between RUM and ESBM. Concentrations of total volatile fatty acids (118.1 vs. 101.5 mM) were greater in RUM in comparison to SB and ESBM diets. Cows fed RUM had greater β-hydroxybutyrate (0.49 vs. 0.42 mmol/L) than SB and ESBM. Selenomonas ruminantium, Succinimonas amylolytica, and Streptococcus bovis in rumen fluid were lower in RUM fed cows in comparison to SB and ESBM. Increased total volatile fatty acids and lower ruminal abundance of bacteria associated with low feed efficiency in RUM cows can partially explain the improvements observed in milk yield and milk efficiency. Overall, these data suggest that feeding a combination of tannin mixture and Capsicum can significantly affect rumen fermentation characteristics via partial manipulation of rumen microbiota, and these effects were reflected in improved milk production and efficiency.

MODELING DNA DAMAGE BY PHOTONS AND LIGHT IONS OVER ENERGY RANGES USED IN MEDICAL APPLICATIONS

Comprehensive track structure-based simulations of DNA damage induced in human cells by photons (5 keV-1.3 MeV) and light ions (0.25-512 MeV/u) were performed with PARTRAC. DNA strand breaks, double-strand breaks and their clustering were scored. Effective LET values were established for photons that provide LET-dependent damage yields in agreement with the data for ions. The resulting database captures the variations of biological effectiveness with radiation quality. In particular, it can help compare the effectiveness of conventional radiotherapy using photon beams with techniques relying on proton or ion beams.

MODELING STUDIES ON DICENTRICS INDUCTION AFTER SUB-MICROMETER FOCUSED ION BEAM GRID IRRADIATION

The biophysical simulation tool PARTRAC contains modules for DNA damage response representing non-homologous end joining of DNA double-strand breaks (DSB) and the formation of chromosomal aberrations. Individual DNA ends from the induced DSB are followed regarding both their enzymatic processing and spatial mobility, as is needed for chromosome aberrations to arise via ligating broken ends from different chromosomes. In particular, by tracking the genomic locations of the ligated fragments and the positions of centromeres, the induction of dicentrics can be modeled. In recent experiments, the impact of spatial clustering of DNA damage on dicentric yields has been assessed in AL human-hamster hybrid cells: Defined numbers of 20 MeV protons (linear energy transfer, LET 2.6 keV/μm), 45 MeV Li ions (60 keV/μm) and 55 MeV C ions (310 keV/μm) focused to sub-μm spot sizes were applied with the ion microbeam SNAKE in diverse grid modes, keeping the absorbed dose constant. The impact of the μm-scaled spatial distribution of DSB (focusing effect) has thus been separated from nm-scaled DSB complexity (LET effect). The data provide a unique benchmark for the model calculations. Model and parameter refinements are described that enabled the simulations to largely reproduce both the LET-dependence and the focusing effect as well as the usual biphasic rejoining kinetics. The predictive power of the refined model has been benchmarked against dicentric yields for photon irradiation.

Effects of a short-term Interval Aerobic Training Programme with active Recovery bouts (IATP-R) on cognitive and mental health, functional performance and quality of life: A randomised controlled trial in sedentary seniors

BACKGROUND

Interval aerobic training programme with active recovery bouts (IATP-R) has shown to improve tolerance to IATP among seniors. However, data concerning its benefits for seniors' health are still limited.

PURPOSE

The purpose of this study was to examine the effects of IATP-R on seniors' health status.

METHODS

Sedentary volunteers (n = 60, aged ≥70 years) were randomly assigned to either IATP-R or maintained sedentary lifestyle for 9.5 weeks. IATP-R consisted of 30-minute cycling (6 × 4 minutes at first ventilatory threshold (VT₁ ) intensity + 1 minute at 40% of VT₁ ) twice a week. Cognitive and functional performances were assessed with the Trail Making Test (TMT-A; TMT-B); Paced Auditory Serial Addition Test (PASAT); Timed Up and Go (TUG) test; 6-Minute Walk Test (6-MWT); one-leg balance test; and the Short Physical Performance Battery (SPPB) tests, respectively. QoL and anxiety/depression status were measured by the Short Form-12 and the Goldberg's Scale, respectively. All participants were assessed at baseline and 9.5 weeks later.

RESULTS

Compared to controls, IATP-R improved cognitive functions (TMT-A: +1.5% vs -21.5%; TMT-B: +0.9% vs -13.3%; PASAT: +1.4% vs -14.6%; semantic fluency: -1.1% vs +11.7%), functional performance (TUG: +5.4% vs -16.5%; 6-MWT: -3.2% vs +11.5%; SPPB: -3.2% vs +14.6%; One-leg balance: -16.3% vs +25.0%); QoL (physical health: -13.3% vs +23.1%; mental health: -7.1% vs +8.2%); and depressive symptoms (+26.3% vs -42.8%). Significant impacts were measured neither on letter modality of fluency tasks nor on anxiety score.

CONCLUSION

These data showed that IATP-R is an effective training programme to improve functional and cognitive performances, mental health and well-being in sedentary seniors. Trial registration ClinicalTrials.gov NCT02263573. Registered October 1, 2014.

Clinical and paraclinical patterns of presentation, and sensitivity of diagnostic scores for pulmonary embolism at the emergencies: retrospective study on the impact of age at the University hospitals of Strasbourg (France)

The diagnosis of pulmonary embolism remains difficult. The objective of this study was to analyze the effect of age on the clinical presentation mode and the sensitivity of the diagnostic scores.

METHODS

In retrospect, all patients discharged with a documented diagnosis of pulmonary embolism from the adult emergency service of the Regional university hospital of Strasbourg (France) over a year were considered. According to 4 age categories (<70, 70-74, 75-80 and >80 years) the data from the medical records were analyzed and compared. Diagnostic scores of Wells and modified Geneva were calculated.

RESULTS

117 patients met the inclusion criteria (mean age 71.8±13.8 years, women 54%). Chest pain was less common after 80 years; no difference was observed for syncope or dyspnea although the oxygen saturation is lower in old age. For diagnosis, 25% of patients had a lung scintigraphy with an increased recourse with age (<70 years: 10%, >80 years: 41%). Thoracic computed tomography angiography concerned 79% of patients with a significant decrease of his use in older. The sensitivity of the diagnostic scores was low but increased with age when the strong and intermediate probabilities of pulmonary embolism were combined.

CONCLUSION

This study confirms the low specificity of the clinical signs of pulmonary embolism, whatever the age. It also shows the low sensitivity of the diagnostic scores in the 70 years or older.

Hematological and biochemical parameters of dairy calves submitted to pegbovigrastim administration

This study was designed to evaluate the response of hematological and biochemical parameters submitted to pegbovigrastim administration and postchallenge with lipopolysaccharide (LPS). In experiment 1, 20 newborn Holstein calves were divided into 2 groups: the Imrestor (Elanco Saúde Animal, São Paulo, Brazil) group (IMR, n = 10), which received a 25 μg/kg of body weight (BW) subcutaneous administration of pegbovigrastim, and the control group (CTR, n = 10), which received a subcutaneous administration of 0.9% saline solution. Blood samples were collected on d 0, 10, 12, and 14 relative to birth to analyze the biochemical and hematological parameters. Moreover, growth measurements were taken on d 0, 7, 14, 21, and 60 relative to birth. The number of total leukocytes in the IMR group increased on d 12 and 14 in comparison to the CTR group, as well as the counts of segmented neutrophils, band cells, and monocytes. No differences were observed in the other hematological, biochemical, and growth parameters. In experiment 2, 20 Holstein calves from 30 to 60 d old were divided into 4 groups: group 1 (LPS, n = 5) received a 0.25 μg/kg of BW single intravenous dose of Escherichia coli LPS at d 0; group 2 (IMR, n = 5) received a 25 μg/kg of BW subcutaneous dose of pegbovigrastim at d 1; group 3 (IMR + LPS, n = 5) received a 0.25 μg/kg of BW intravenous LPS dose at d 0 and a 25 μg/kg of BW subcutaneous dose of pegbovigrastim at d 1; and group 4 (CTR, n = 5) received an intravenous dose of 0.9% sodium chloride at d 0 and a subcutaneous dose of 0.9% sodium chloride at d 1. For the analysis of biochemical and hematological parameters, blood samples were collected on d -1, 0, 1, 2, 3, 4, 8, 14, and 21 relative to LPS administration. An increase in the number of total leukocytes was observed in the IMR, IMR + LPS, and LPS groups, and the IMR group remained as the highest from d 2 to 21. The levels of paraoxonase 1 were higher in the IMR group compared with all the others. The administration of pegbovigrastim in the dairy calves increased the number of circulating leukocytes, especially neutrophils, with an increase in paraoxonase 1, without altering the metabolites for the hepatic function.

AT THE PHYSICS-BIOLOGY INTERFACE: THE NEUTRON AFFAIR

We present predictions of neutron relative biological effectiveness (RBE) for cell irradiations with neutron beams at PTB-Braunschweig. A neutron RBE model is adopted to evaluate initial DNA damage induction given the neutron-induced charged particle field. RBE values are predicted for cell exposures to quasi-monoenergetic beams (0.56 MeV, 1.2 MeV) and to a broad energy distribution neutron field with dose-averaged energy of 5.75 MeV. Results are compared to what obtained with our RBE predictions for neutrons at similar energies, when a 30-cm sphere is irradiated in an isotropic neutron field. RBE values for experimental conditions are higher for the lowest neutron energies, because, as expected, target geometry determines the weight of the low-effectiveness photon component of the neutron dose. These results highlight the importance of characterizing neutron fields in terms of physical interactions, to fully understand neutron-induced biological effects, contributing to risk estimation and to the improvement of radiation protection standards.

Bioacústica como método de avaliação do comportamento em pastejo de novilhas Girolando

RESUMO Objetivou-se validar o método de análise de dados bioacústicos na descrição do comportamento em pastejo de novilhas em área de integração lavoura-pecuária (iLP) e floresta (iLPF). Foram utilizadas oito novilhas Girolando (¾Holandês x ¼Gir) com média de 25±6,8 meses de idade e 268±83kg de peso vivo (PV), distribuídas em delineamento crossover 2x2 (dois sistemas x dois períodos de avaliação). A coleta de dados para análise bioacústica foi realizada utilizando-se gravadores MP3. Esses dados foram analisados pelo software Audacity® para identificação das atividades de pastejo, ruminação e ócio. Concomitantemente, o comportamento também foi avaliado pelo método de observação visual, realizado no período de 8 até 16 horas, em intervalos de 15 minutos. Não houve diferença (P>0,05) entre médias dos tempos (minutos) de pastejo, ruminação e ócio registrados pelos métodos de bioacústica e avaliação visual, sendo, respectivamente, 127 vs. 137; 122 vs. 113 e 238 vs. 216, no sistema iLP, e 134 vs. 103; 130 vs. 165 e 233 vs. 203, no sistema iLPF. Por meio desses resultados, foi possível concluir que o método da bioacústica é uma importante ferramenta para avaliar o comportamento de pastejo em diferentes sistemas de produção a pasto, com a vantagem de possibilitar o registro de atividades durante o período noturno, além de maior praticidade e precisão do que o método observacional.

Einfluß des Therapiekonzepts auf die Prognose des Schilddrüsenkarzinoms

Das von uns angewandte Therapiekonzept für die Behandlung des Schilddrüsenkarzinoms sieht eine fakultative perkutane Nachbestrahlung des Halses und eine obligate, intensive Nachbehandlung mit Radiojod vor. Letztere beinhaltet eine vollständige Elimination von Restgewebe und eine kombiniert diagnostische und therapeutische Radiojodgabe in der Nachsorge. Die therapeutische Wirkung von Operation, Hormonsubstitution, Radiojodtherapie und perkutaner Nachbestrahlung zusammen auf die Prognose des Schilddrüsenkarzinoms war offensichtlich, jene von Einzelmaßnahmen erwies sich dagegen als schwer abgrenz- und quantifizierbar. Ein günstiger Einfluß der perkutanen Strahlentherapie konnte nur beim anaplastischen, nicht dagegen beim follikulären Karzinom belegt werden. Trotz prophylaktischer Anwendung von Radiojod in hohen Dosen war die Prognose des differenzierten Schilddrüsenkarzinoms weiterhin vorrangig von biologischen Determinanten abhängig. Die Radiojodbehandlung wird bei allen Patienten mit follikulärem Karzinom und bei Patienten älter als 30 Jahre mit papillärem Karzinom empfohlen, die prophylaktische Behandlung sollte aber auf die Dauer von 5 Jahren begrenzt bleiben.

Untersuchungen zur Monozytopoese bei malignen Erkrankungen und unter B CG-Immunstimulation mit Hilfe des DNA-Markers 3H-Thymidin

Bei Patienten mit Morbus Hodgkin, Non-Hodgkin-Lymphom, Mycosis fungoides, Mammakarzinom oder malignem Melanom wurde die monozytopoetische Proliferationsaktivität im Knochenmark und Blut untersucht. Bei allen Patienten wurde die Studie vor der Behandlung durchgeführt. Bei einem Teil der Patienten erfolgte eine nochmalige Untersuchung nach der Operation und der prophylaktischen Immunstimulation mit BCG. Bei allen Patienten mit unbehandeltem Malignom lag eine mehr oder weniger ausgeprägte Stimulation der Monozytopoese vor. Bei der postoperativ durchgeführten prophylaktischen Behandlung mit BCG konnte vorübergehend eine Zunahme der Proliferationsaktivität der Monozytopoese beobachtet werden. Nach der vierten BCG-Immunstimulation fielen die Werte jedoch in den Normbereich ab. Die Ergebnisse machen deutlich, daß bei Patienten mit Malignomen ein erhöhter Monozytenbedarf vorliegt. Eine Immunstimulation mit BCG in der von uns durchgeführten Weise steigert die Proliferationsaktivität der Monozytopoese. Dieser Effekt ist jedoch vorübergehend.

Effect of porcine somatotropin on metabolism, testicular size and sperm characteristics in young boars

ABSTRACT The aim of this study was to evaluate the effect of pST injections on metabolism, testicular size, and sperm characteristics in young boars. Sixty 22-day old piglets were divided into two groups: pST (n=30) and Control (n=30). The pST group was submitted to pST injections (90µg/kg body weight) every three days up to 330 days of age. Blood collections were performed weekly. Testicular weight was measures at 22, 82, 142, 202 and 365 days of age. Libido and fresh semen characteristics were evaluated between 150 and 210 days of age. Semen characteristics were also evaluated during a 72h storage period (15ºC). Testosterone, albumin, and phosphorus blood concentrations were higher in the pST group (P<0.05). The pST group had a higher IGF-I concentration in seminal plasma (P=0.05) and higher testicular weight (P<0.001) compared to the Control group. The pST group had higher ejaculate volume (P<0.001), total sperm count (P=0.047) and number of inseminating doses/ejaculate (P=0.047). During the 72h storage period, the pST group had a lower number of morphological alterations (P<0.001) compared to the Control group. In sum, pST injection in young boars increased testosterone concentration, testicular size, and sperm quality.

Combinação de butafosfan e cianocobalamina no metabolismo da glicose em vacas leiteiras após o parto

RESUMO A hipótese deste estudo é de que o uso da combinação de butafosfan e cianocobalamina pode melhorar a resistência periférica à insulina, aumentar a quantidade de glicose disponível para a glândula mamária e a produção de leite. Assim, o objetivo foi investigar os efeitos combinados de butafosfan e cianocobalamina sobre o metabolismo da glicose em vacas leiteiras no período pós-parto. Vinte e uma vacas leiteiras foram divididas em dois grupos: grupo controle (CON, n= 11), que recebeu cinco aplicações de solução salina (20mL / animal 0,9% NaCl), e grupo Catosal(r) (ABC, n= 10), que recebeu cinco aplicações de 20mL de uma solução contendo as substâncias butafosfan e cianocobalamina (B12 Catosal(r), 100mg da substância butafosfan e 50µg de cianocobalamina por mL). As aplicações foram realizadas por via intramuscular, nos dias sete, 12, 17, 22 e 27 pós-parto. As amostras de sangue foram coletadas para a avaliação das concentrações plasmáticas de fósforo, glicose, ácidos graxos não esterificados (AGNE), albumina, aspartato aminotransferase (AST) e creatina quinase (CK). Nos dias oito e 28 pós-parto, os animais foram pesados e submetidos aos testes de tolerância à glicose e à insulina. O tratamento promoveu perda de peso (ABC 40,4kg, CON 10,73kg, P<0,05) e aumento da AST (ABC 62,92 ±3,31U/L, CON 53,11±3,49 U / L, P<0,05) e dos níveis de CK (ABC 134,09± 19,08U / L, CON 79,43 ± 18,27U / L). Os grupos não diferiram quanto ao metabolismo (área sob a curva) da glicose nos dias oito e 28, porém os animais tratados tiveram um aumento na glicemia (P<0,05) no dia 28 pós-parto (97,54 ± 8,54mg / dL), após a administração de insulina, em comparação ao dia oito (83,01 ± 8,54mg / dL). Assim, pode-se concluir que a combinação de butafosfan e cianocobalamina melhora a adaptação do metabolismo da glicose em vacas leiteiras no início da lactação.

Comprehensive track-structure based evaluation of DNA damage by light ions from radiotherapy-relevant energies down to stopping

Track structures and resulting DNA damage in human cells have been simulated for hydrogen, helium, carbon, nitrogen, oxygen and neon ions with 0.25–256 MeV/u energy. The needed ion interaction cross sections have been scaled from those of hydrogen; Barkas scaling formula has been refined, extending its applicability down to about 10 keV/u, and validated against established stopping power data. Linear energy transfer (LET) has been scored from energy deposits in a cell nucleus; for very low-energy ions, it has been defined locally within thin slabs. The simulations show that protons and helium ions induce more DNA damage than heavier ions do at the same LET. With increasing LET, less DNA strand breaks are formed per unit dose, but due to their clustering the yields of double-strand breaks (DSB) increase, up to saturation around 300 keV/μm. Also individual DSB tend to cluster; DSB clusters peak around 500 keV/μm, while DSB multiplicities per cluster steadily increase with LET. Remarkably similar to patterns known from cell survival studies, LET-dependencies with pronounced maxima around 100–200 keV/μm occur on nanometre scale for sites that contain one or more DSB, and on micrometre scale for megabasepair-sized DNA fragments.