Botulinum toxin injections reduce associative plasticity in patients with primary dystonia

Botulinum toxin injections ameliorate dystonic symptoms by blocking the neuromuscular junction and weakening dystonic contractions. We asked if botulinum toxin injections in dystonia patients might also affect the integrity of sensorimotor cortical plasticity, one of the key pathophysiological features of dystonia. We applied a paired associative stimulation protocol, known to induce long‐term potentiation–like changes in the primary motor cortex hand area to 12 patients with cervical dystonia before and 1 and 3 months after botulinum toxin injections to the neck muscles. Primary motor cortex excitability was probed by measuring transcranial magnetic stimulation‐evoked motor evoked potentials before and after paired associative stimulation. We also measured the input–output curve, short‐interval intracortical inhibition, intracortical facilitation, short afferent inhibition, and long afferent inhibition in hand muscles and the clinical severity of dystonia. Before botulinum toxin injections, paired associative stimulation significantly facilitated motor evoked potentials in hand muscles. One month after injections, this effect was abolished, with partial recovery after 3 months. There were significant positive correlations between the facilitation produced by paired associative stimulation and (1) the time elapsed since botulinum toxin injections and (2) the clinical dystonia score. One effect of botulinum toxin injection treatment is to modulate afferent input from the neck. We propose that subsequent reorganization of the motor cortex representation of hand muscles may explain the effect of botulinum toxin on motor cortical plasticity. © The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.     

Comparison of atrial contribution to cardiac hemodynamics in patients with normal and severely compromised cardiac function

The importance of atrial contribution to cardiac function in patients with congestive heart failure is controversial. Ten patients with severe congestive failure (Group A) and 10 patients with normal ventricular function (Group B) were studied during atrial and ventricular pacing. Left ventricular ejection fraction, baseline pulmonary capillary wedge pressure, and baseline cardiac index were different between Group A and Group B patients: 22 +/- 10 vs. 65 +/- 11 (p less than 0.01); 21 +/- 5 vs. 8 +/- 4, (p less than 0.01); and 2.8 +/- 0.5 vs. 3.5 +/- 1.0 (p = 0.05). Compared with atrial pacing, cardiac index decreased from 2.8 +/- 0.6 to 2.2 +/- 0.5 (p less than 0.01) in Group A and from 3.6 +/- 0.7 to 2.9 +/- 0.5 (p less than 0.01) in Group B, during ventricular pacing. Pulmonary capillary wedge pressure increased by similar amounts in both groups during ventricular pacing. The change in cardiac index, % change in cardiac index, and change in pulmonary capillary wedge pressure from atrial to ventricular pacing, were not different between Group A and Group B patients. By logistic regression analysis, no association was found between the % change in cardiac index and the following variables: left ventricular ejection fraction, left ventricular end-diastolic volume, baseline pulmonary capillary wedge pressure, change in pulmonary capillary wedge pressure, and baseline cardiac index. The atrial contribution to resting steady-state cardiac function is similar between patients with severe congestive failure and those with preserved ventricular function.     

Does blood rheology revert to normal after myocardial infarction?

After myocardial infarction there is an acute deterioration of the flow properties of blood. The present study was designed to test whether the abnormality persists. Blood and plasma viscosity, red cell aggregation and deformability, haematocrit, erythrocyte sedimentation rate, white cell count, cholesterol, and triglycerides were measured in 51 patients who had had a myocardial infarction 5.4 (mean) years before. Results in patients and controls were compared and matched pairs with identical cardiovascular risk factors were also selected. Blood viscosity and red cell aggregation were increased and red cell deformability was decreased in the 51 patients. The abnormalities were independent of the interval since infarction and persisted for years. The rheological abnormalities present after myocardial infarction are at least partly independent of the acute event and acute phase reactions. They contribute to the reduced perfusion of the microcirculation of the heart.     

Specificity of rabbit antisera against the rough lipopolysaccharide of Salmonella minnesota R4 (chemotype Rd2P-)

Rabbit polyclonal antibodies against the rough mutant lipopolysaccharide (LPS) of Salmonella minnesota R4 (chemotype Rd2P-) were serologically characterized by using R4 LPS, deacylated LPS, dephosphorylated LPS, and synthetic partial structures, including compounds comprising the core region of Rd2P- LPS bound to the beta 1-->6-linked glucosamine disaccharide with two amide-linked 3-hydroxytetradecanoic acid residues or coupled to bovine serum albumin. By using a passive hemolysis assay and an enzyme immunoassay and absorption and inhibition experiments, the antibody specificities present could be determined. One group of antibodies required components of the core oligosaccharide (with or without the side chain 3-deoxy-D-manno-octulosonic acid [Kdo]) and the phosphorylated glucosamine disaccharide of the lipid A moiety for binding. The phosphate-independent antibodies were directed against the core oligosaccharide, recognizing an epitope consisting of one terminal heptose linked to Kdo or to the reducing moiety of the alpha 2-->4-linked Kdo disaccharide. Antibodies requiring the presence of acyl residues and those reacting with a single heptose or Kdo residue were not detected.     

Effects of low-level light therapy on xerostomia related to hyposalivation: a systematic review and meta-analysis of clinical trials

Lasers in Medical Science - Hyposalivation is a condition represented by a reduced salivary flow and may include symptoms such as mouth dryness (xerostomia), loss of taste, pain, dysphagia, and...     

Validation of low-cost models for minimal invasive surgery training of congenital diaphragmatic hernia and esophageal atresia

BackgroundMinimal invasive surgery (MIS) is increasingly used for the correction of congenital diaphragmatic hernia (CDH) and esophageal atresia (EA). It is important to master these complex procedures, preferably preclinically, to avoid complications. The aim of this study was to validate recently developed models to train these MIS procedures preclinically.MethodsTwo low cost, reproducible models (one for CDH and one for EA) were validated during several pediatric surgical conferences and training sessions (January 2017–December 2018), used in either the LaparoscopyBoxx or EoSim simulator. Participants used one or both models and completed a questionnaire regarding their opinion on realism (face validity) and didactic value (content validity), rated on a five-point-Likert scale.ResultsOf all 60 participants enrolled, 44 evaluated the EA model. All items were evaluated as significantly better than neutral, with means ranging from 3.7 to 4.1 (p < 0.001). The CDH model was evaluated by 48 participants. All items scored significantly better than neutral (means 3.5–3.9, p < 0.001), with exception of the haptics of the simulated diaphragm (mean 3.3, p = 0.054). Both models were considered a potent training tool (means 3.9).ConclusionThese readily available and low budget models are considered a valid and potent training tool by both experts and target group participants.Type of studyProspective study.Level of evidenceLevel II.     

Fear of hypoglycemia,a game changer during physical activity in type 1 diabetes mellitus patients

Hypoglycemia limits optimal glycemic management of patients with type 1 diabetes mellitus (T1DM). Fear of hypoglycemia (FoH) is a significant psychosocial consequence that negatively impacts the willingness of T1DM patients to engage in and profit from the health benefits of regular physical activity (e.g., cardiometabolic health, improved body composition, cardiovascular fitness, quality of life). Technological advances, improved insulin regimens, and a better understanding of the physiology of various types of exercise could help ameliorate FoH. This narrative review summarizes the available literature on FoH in children and adults and tools to avoid it.     

Effects of non-thermal atmospheric plasma treatment on dentin wetting and surface free energy for application of universal adhesives

Objectives

The study aims to evaluate the effects of non-thermal atmospheric plasma (NTAP) treatments on dentin wetting and surface free energy (SFE) and compare the effects of NTAP treatment, etch-and-rinse, and self-etch protocols for application of universal adhesives.

Materials and methods

Mid-coronal dentin of intact third molars was used to measure contact angles of distilled water, ethylene-glycol, and diiodomethane and calculate SFE following different NTAP preset treatments (feeding gas consisting of pure He, He + 1% O₂, He + 1.5% O₂), power input (1 or 3 W), and tip-to-surface distance (2, 4, or 8 mm). Contact angles of reference liquids and SFE of dentin following He + 1.5% O₂ at 3-W and 4-mm treatment was compared to phosphoric acid etching. Contact angles of Single Bond Universal (SBU; 3M ESPE) and Clearfil Universal Bond (CUB; Kuraray Noritake) were measured following NTAP, etch-and-rinse, and self-etch protocols.

Results

NTAP significantly reduced contact angles of reference liquids and increased dentin SFE compared to untreated dentin (p < 0.05). O₂ intensified the effect of He NTAP (p < 0.05). NTAP and phosphoric acid increased dentin polarity and Lewis base surface characteristics. Phosphoric acid increased contact angles of adhesives compared to the self-etch protocol (p < 0.05). NTAP resulted in lower adhesive contact angles than phosphoric acid, the difference being statistically significant for CUB (p < 0.05). Compared to the self-etch protocol, NTAP slightly reduced CUB contact angle but not that of SBU (p > 0.05).

Conclusions

He NTAP with and without O₂ increased dentin wetting and SFE, surpassing the effect of phosphoric acid and lowering adhesive contact angles. NTAP produced no apparent micro-morphological changes on dentin surface comparable to acid etching.

Clinical significance

NTAP treatment of dentin prior to adhesive application increases dentin wetting and surface free energy facilitating better adhesive distribution on dentin surface compared to phosphoric acid etching and similar to the “self-etch” application protocol.

     

Effect of UVC radiation on mouse fibroblasts deficient for FAS-associated protein with death domain

Purpose: Ultraviolet (UV) radiation-induced apoptosis enabled us to study the mechanism of DNA damage and to investigate how cells avoid consequences of damaged DNA. Cells with extensive DNA damage activate extrinsic and intrinsic pathways of apoptosis. The extrinsic pathway is coupled to a FAS-associated protein with death domain (FADD), an adaptor protein molecule necessary for mediating apoptotic signals through the cell.

Materials and methods: Viability and apoptosis of wild-type and FADD-deficient mouse embryonic fibroblasts were investigated 1, 3, 24 and 48?h after exposure to three doses (50, 75 and 300 J/m²) of UVC radiation. Morphological changes were observed using DNA binding dyes (Hoechst and propidium iodide) while biochemical changes were monitored using immunodetection of the poly (ADP-ribose) polymerase (PARP) protein cleavage and caspase-3 activity assay.

Results: Results showed that the difference in cell death response between wild-type and FADD-deficient cells depended on dose and incubation time after exposure to UVC radiation. FADD-deficient cells are more sensitive to UVC radiation. Even though FADD-deficient cells lack an adapter protein of apoptotic extrinsic pathway, higher doses of UVC triggered their apoptotic response, while wild-type cells die mainly due to necrosis. A different pattern of caspase 3 activity and PARP cleavage was observed 24?h after radiation between two cell lines confirming higher apoptotic response in FADD-deficient cells.

Conclusions: Wild-type cells can execute apoptosis via both, the mitochondrial and the receptor-mediated pathway whereas FADD-deficient cells can only activate the intrinsic pathway. There is a difference in UVC radiation response between two cell lines indicating the role of FADD in the selection of cell death modality.     

Matrix metalloproteinase-9 -1562 C/T gene polymorphism in Serbian patients with multiple sclerosis

Matrix metalloproteinase-9 (MMP-9) is suggested to play a role in MS by mediating T cell migration across subendothelial basement membrane and by contribution to myelin breakdown. We studied the association of MMP-9 -1562 C/T gene polymorphisms with MS susceptibility and severity in 187 patients from Serbia. The significant decrease in T allele carriership (p = 0.01), was found in female MS patients. In addition, a trend toward lower MSSS in T allele carriers was noticed (CC, mean 5.7 +/- 2.5 vs. CT+TT, mean 4.9 +/- 2.5). Further studies in different populations are needed to resolve the potential influence of MMP-9 gene polymorphism on MS.