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Porphyrin derivatives are known singlet oxygen sensitizers in photodynamic therapy (PDT). Energy transfer from a class of diolefinic laser dyes (DOLDs) as energy donors to the sodium salt of meso-tetrakis (4-sulfonatophenyl) porphyrin (TPPS) as the accepter of energy would extend the range of photon harvesting down to the UV-region. Energy transfer was substantially enhanced in the presence of metallic silver nanoparticles (AgNPs), as revealed by steady-state emission spectroscopy, lifetimes, and quantum mechanics. DOLDs under investigation are 2,5-distyrylpyrazine (DSP), 1,4-bis (β-pyridyl-2 vinyl) benzene (P2VB), and 1,4 bis (2-methylstyryl) benzene (MSB) as efficient donors of intense absorption in the UV-region. AgNPs enhance the rate of energy transfer from DOLDs to TPPS via bringing donor and acceptor into close- proximity with a concomitant increase in dipole–dipole interaction between excited state donor and ground-state acceptor. The DOLDs molecular structures were optimized using the DFT/CAM-B3LYP/6-311G++ (d, p) level of theory. The calculated electronic absorption spectra for the studied DOLDs in the gaseous phase and methanol solvent were studied using the time-dependent density functional theory (TD-DFT) at M06-2X/6-311G++ (2d,2p) level. The calculated absorption/emission spectra for DSP laser dye in methanol are obtained at the TD/ M06-2X/6-311G++(2d, 2p) method. Notably, all theoretical results of the molecular structures under study highly agreed with the practical optical results. Energy transfer rate constants (kET) amid energy donor/acceptor pairs were determined by Stern-Volmer constants (KSV) and donors' lifetime measurements. The KSV values indicate an enhanced Fluorescence Resonance Energy Transfer (FRET) efficiencies in the presence of negatively charged AgNPs. The critical transfer distances Ro were determined from the spectral overlap between the emission spectrum of donor and absorption spectrum of TTPS. These outcomes propose the application of designed metal-enhanced FRET for energy-transfer-based assays and photodynamic therapy (PDT) applications.

In the present paper, a one-step, simple, efficient and low-cost strategy was demonstrated for preparing of highly stable hybrid platinum-titania (Pt@TiO2) photocatalyst by solvothermal wet chemical process. Platinum (Pt) in the metallic form combined with titania (TiO2) in the crystallographic anatase form has been manufactured using Dimethyl Sulfoxide (DMSO) as a solvent and surfactant using titanium (IV) butoxide and hydrogen hexachloroplatinate(IV) precursors. Full characterization of the hybrid nanomaterials including their morphology, crystalline structure and optical properties was determinate using different experimental techniques such as XRD, TEM and UV–vis spectroscopy. TEM images showed spherically shaped Pt nanoparticles (NPs) of the diameter 5–10 nm with good particle size distribution. The EDXRF data revealed that Pt NPs are in metallic form. Optical investigation show that Pt@TiO2 NPs exhibits a good optical response under UV–vis light excitation compared to bare-TiO2. Furthermore, photocatalytic investigation of Pt@TiO2 colloids photocatalyst towards the photodegradation of diuron, as a model organic pesticide was reported. The hybrid Pt@TiO2 photocatalyst prove high-performance on the photodecomposition of the pesticide under solar light within only 60 min. In the other hand, the plasmonic hybrid Pt@TiO2 was incorporated into the cotton fabric to attain a modified fiber with high self-cleaning activity. Keywords: Solvothermal method, Nanocomposites, Semiconductors, Heterogenous catalysis, Cotton fiber, Self-cleaning

This review aims to update the current knowledge on the cerebral control of swallowing. We review data from both animal and human studies spanning across the fields of neuroanatomy, neurophysiology and neuroimaging to evaluate advancements in our understanding in the brain's role in swallowing. Studies have collectively shown that swallowing is mediated by multiple distinct cortical and subcortical regions and that lesions to these regions can result in dysphagia. These regions are functionally connected in separate groups within and between the two hemispheres. While hemispheric dominance for swallowing has been reported in most human studies, the laterality is inconsistent across individuals. Moreover, there is a shift in activation location and laterality between swallowing preparation and execution, although such activation changes are less well-defined than that for limb motor control. Finally, we discussed recent neurostimulation treatments that may be beneficial for dysphagia after brain injury through promoting the reorganization of the swallowing neural network., (Copyright © 2022 The Author(s). Published by Elsevier B.V. All rights reserved.)

Producing nanomaterials from hazardous wastes for water and soil treatment is of great concern. Here, we produced and fully characterized two novel nanomaterials from sugar beet processing (SBR)- and brick factory-residuals (BFR) and assed their ability for Cd and Cu sorption in water and reducing metal availability in a contaminated soil. The SBR removed up to 99% of Cu and 91% of Cd in water, and exhibited a significantly faster and higher sorption capacity (q max (g kg -1 ) = 1111.1 for Cu and 33.3 for Cd) than BFR (q max (g kg -1 ) = 33.3 for Cu and 10.0 for Cd), even at acidic pH. Soil metal availability was significantly reduced by SBR (up to 57% for Cu and 86% for Cd) and BFR (up to 36% for Cu and 68% for Cd) compared to the unamended soil. The higher removal efficacy of SBR over BFR could be attributed to its higher alkalinity (pH = 12.5), carbonate content (82%), and specific surface area, as well as the activity of hydroxyl -OH and Si-O groups. The nano-scale SBR and BFR, the former particularly, are novel, of low cost, and environmental friendly amendments that can be used for the remediation of metal-contaminated water and soil., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Objectives: To evaluate the effects of neurostimulation, including repetitive transcranial magnetic stimulation (rTMS), transcranial direct current stimulation (tDCS) and pharyngeal electrical stimulation (PES), for poststroke dysphagia based on evidence from randomized controlled trials (RCTs)., Materials and Methods: Electronic databases were systematically searched between January 1985 and June 2020 and studies were included based on prespecified selection criteria. The quality of studies was evaluated and data were extracted and synthesized by two independent reviewers. The primary outcome measure was change in (any) relevant clinical swallowing-related characteristic. Subgroup analysis were conducted based on follow-up period and stimulation parameters., Results: Data from 852 stroke patients were collected from 26 RCTs studies. Active neurostimulation treatments demonstrated a significant and moderate effect size compared to control treatment (0.69 [95% CI = 0.50, 0.89]; p < 0.001). The effect size of rTMS was the largest (0.73 [95% CI = 0.49, 0.98]; p < 0.001), followed by PES (0.68 [95% CI = 0.22, 1.14]; p = 0.004) and tDCS (0.65 [95% CI = 0.25, 1.04]; p = 0.001). All treatments showed comparable effect sizes within the first two weeks. Between three weeks and two months, tDCS demonstrated the largest effects (1.02 [95% CI = 0.45, 1.59]; p < 0.001) among the three treatments. No significant treatment effects were reported beyond three months. The combined effect size was large when applied in acute (<14 days) stroke (0.8 [95% CI = 0.34, 1.26]; p < 0.001). For noninvasive brain stimulation (NIBS), bihemispheric stimulation demonstrated the strongest effect size (0.93 [95% CI = 0.53, 1.33]; p < 0.001). In contrast, unilateral rTMS using ipsilesional high-frequency stimulation had a combined effect size of 0.83 (95% CI = 0.14, 1.52; p = 0.02). For tDCS, a significant effect size was found only with anodal stimulation applied over the contralesional hemisphere (1.04 [95% CI = 0.54, 1.53]; p < 0.001)., Conclusions: The results show that neurostimulation can benefit patients with poststroke dysphagia. The treatment effects were the strongest in acute stroke patients and within the first two months of application. For NIBS, bihemispheric stimulation appeared to be most effective. The most beneficial hemisphere for unilateral stimulation differed between rTMS and tDCS. These findings provide a platform for future studies and clinical practice., (© 2020 The Authors. Neuromodulation: Technology at the Neural Interface published by Wiley Periodicals LLC on behalf of International Neuromodulation Society.)

Objectives: Translumbosacral neuromodulation therapy (TNT) improves symptoms of fecal incontinence (FI), but its mechanism of action is unknown. We tested the hypothesis that TNT at one or more frequency will significantly improve underlying pathophysiology of FI through modulation of ascending and/or descending signaling pathways in the gut and brain axis and anorectal sensorimotor function., Materials and Methods: We assessed afferent anorectal-cortical evoked potentials (CEP) following electrical stimulation of anorectum, efferent cortico-anorectal and lumbo-anorectal and sacro-anorectal motor evoked potentials (MEP) after transcranial and lumbosacral magnetic stimulations, and anorectal manometry before and after six weekly TNT sessions in FI subjects, randomized to 1, 5, or 15 Hz repetitive magnetic stimulations. Neurophysiology, anorectal sensorimotor function, and symptoms were compared to examine mechanistic effects. Co-primary measures were ano-cortical CEPs, cortico-anal MEPs, and lumbosacral-anal MEPs. Baseline and post-treatment data were compared with Wilcoxon signed-rank test and changes between the three frequencies with one-way ANOVA., Results: Thirty-three FI patients participated. After TNT, the afferent anal CEP latencies significantly decreased in the 1 Hz group compared to baseline (p = 0.0029) and 5 Hz or 15 Hz groups (p = 0.032). Cortico-anal MEPs were unchanged in all three groups. Bilateral lumbo-anal and sacro-anal MEP latencies significantly decreased with 1 Hz, lumbo-anal with 15 Hz, and sacro-anal with 5 Hz compared to baseline but without group differences. The 1 Hz group showed significant increase in anal squeeze sphincter pressure (p < 0.005) and maximum tolerable volume (p < 0.019) and demonstrated higher FI responder rate (p < 0.04) compared to the other two groups. The MEP responders were significantly correlated with FI responders (p = 0.006) in 1 Hz group., Conclusions: TNT significantly improves afferent ano-cortical signaling, efferent lumbo-anal and sacro-anal neuropathy and anorectal sensorimotor function. These neurobiologic effects were most prominent with 1 Hz frequency. TNT improves FI by modifying the underlying pathophysiology possibly through neuromodulation., (© 2021 International Neuromodulation Society.)

COVID-19, the pandemic disease recently discovered in Wuhan (China), severely spread and affected both social and economic activity all over the world. Attempts to find an effective vaccine are challenging, time-consuming though interminable. Hence, re-proposing effective drugs is reliable and effective alternative. Taking into account the genome similarity of COVID-19 with SARS-CoV, drugs with safety profiles could be fast solution. Clinical trials encouraged the use of Chloroquine and Hydroxychloroquine for COVID-19 inhibition. One of the possible inhibition pathways is the competitive binding with the angiotension-converting enzyme-2 (ACE-2), in particular with the cellular Sialic acid (Neu5Ac). Here, we investigate the possible binding mechanism of ClQ and ClQOH with sialic acid both in the gas phase and in water using density functional theory (DFT). We investigated the binding of the neutral, monoprotonated and diprotonated ClQs and ClQOHs to sialic acid to simulate the pH effect on the cellular receptor binding. DFT results reveals that monoprotonated ClQ + and ClQOH + , which account for more than 66% in the solution, possess high reactivity and binding towards sialic acid. The Neu5Ac-ClQ and the analogues Neu5Ac-ClQOH adducts were stabilized in water than in the gas phase. The molecular complexes stabilize by strong hydrogen bonding and π - π stacking forces. In addition, proton-transfer in Neu5Ac-ClQOH + provides more stabilizing power and cellular recognition binding forces. These results shed light on possible recognition mechanism and help future breakthroughs for COVID-19 inhibitors., Competing Interests: Conflict of interest: the authors declare no conflict of interest, (© 2020 Elsevier B.V. All rights reserved.)

Objective: we investigated the effect of anodal transcranial direct current stimulation (tDCS) applied over the pharyngeal motor area in dysphagia associated with multiple sclerosis (MS)., Methods: Eighteen MS patients with dysphagia associated with brainstem involvement were randomized to receive either "real" or "sham" tDCS., Primary Outcome: The Penetration/Aspiration Scale (PAS)., Secondary Outcomes: changes in electromyographic (EMG) parameters and pharyngeal cortical motor evoked potentials (MEPs). Patients were evaluated at baseline (T 0 ), at the end of 5-session cycle of tDCS stimulations (T 1 ), after two (T 2 ), and four (T 3 ) weeks., Results: the PAS values were significantly lower in the active group than in "sham" group at T 1 , and at T 3 . Over the post-stimulation periods, PAS significantly improved only in the "real" group. As regards the secondary outcomes, we observed a statistically significant difference between the 2 groups only in the MEPs amplitude at T 1 . The comparison between baseline and each of the post-stimulation times showed significant differences only of the "real" group across all the secondary parameters., Conclusions: Our findings support a beneficial effect of anodal tDCS applied to the pharyngeal motor cortex in MS-associated dysphagia., Significance: Considering its safety and efficacy, tDCS may represent an important resource in MS-associated dysphagia., (Copyright © 2019. Published by Elsevier B.V.)

Neurogenic dysphagia frequently occurs after stroke and deglutitive aspiration is one of the main reasons for subacute death after stroke. Although promising therapeutic interventions for neurogenic dysphagia are being developed, the functional neuroanatomy of recovered swallowing in this population remains uncertain. Here, we investigated 18 patients post-stroke who recovered from dysphagia using an event related functional magnetic resonance imaging (fMRI) study of swallowing. Patients were characterized by initial dysphagia score (mild to severe), lesion mapping, white matter fractional anisotropy (FA) of the pyramidal tracts, and swallowing performance measurement during fMRI scanning. Eighteen age matched healthy participants served as a control group. Overall, patients showed decreased fMRI-activation in the entire swallowing network apart from an increase of activation in the contralesional primary somatosensory cortex (S1). Moreover, fMRI activation in contralesional S1 correlated with initial dysphagia score. Finally, when lesions of the pyramidal tract were more severe, recovered swallowing appeared to be associated with asymmetric activation of the ipsilesional anterior cerebellum. Taken together, our data support a role for increased contralesional somatosensory resources and ipsilesional anterior cerebellum feed forward loops for recovered swallowing after dysphagia following stroke.

The molecular complex between 1-(2-methoxyphenyl)-1H-imidazole-2(3H)-thione (Hmim(OMe)) and iodine (I2) was investigated. Single crystal of [(Hmim(OMe))I2] adduct was grown by slow evaporation technique from chloroform at room temperature. Spectroscopic techniques such as FT-IR and Raman techniques, as well as elemental and thermal analysis were used to characterize the complex. The crystal structure shows that the formed adduct stabilized by two noncovalent interactions, namely, hydrogen bond (HB) and halogen bond (XB). Orthogonal HB/XB associated with iodine atom (I) was observed and fully characterized. The ability of iodine to behave as hydrogen bond acceptor and halogen bond donor was held responsible for the orthogonal HB/XB presence. In addition, the structure of Hmim(OMe)I2 was investigated theoretically using MP2/aug-cc-pVDZ level of theory. Natural bond orbital analysis (NBO) was used to investigate the molecular orbitals interactions and orbitals stabilization energies., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Molecular charge-transfer complexes (CT) between thiazoline-2-thione (THZ) and different σ- (I2) and π-acceptors (Tetracyanoethylene (TCNE), 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), and 2,3,5,6-tetrachloro-1,4-benzoquinone (CHL)) were investigated. UV-Vis absorption spectroscopy and theoretical calculations using both MP2/aug-cc-pVDZ-PP and B3LYP/6-311++G(d,p) level of theory were corroborated to study the nature of the stabilizing forces for THZ-I2, THZ-DDQ, THZ-TCNE, and THZ-CHL. Halogen bonding (XB) was the stabilizing attractive force in THZ-I2 and THZ-CHL whereas; hydrogen bonding (HB) was dominated in both THZ-TCNE, and THZ-DDQ complexes. Formation constant (K), extinction coefficient (ɛ), thermodynamic parameters such as enthalpy change (ΔH), entropy (ΔS), and Gibbs free energy (ΔG) were measured in different solvents., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Background: Swallowing problems following stroke may result in increased risk of aspiration pneumonia, malnutrition, and dehydration., Objective/hypothesis: Our hypothesis was that three neurostimulation techniques would produce beneficial effects on chronic dysphagia following stroke through a common brain mechanism that would predict behavioral response., Methods: In 18 dysphagic stroke patients (mean age: 66 ± 3 years, 3 female, time-post-stroke: 63 ± 15 weeks [±SD]), pharyngeal electromyographic responses were recorded after single-pulse transcranial magnetic stimulation (TMS) over the pharyngeal motor cortex, to measure corticobulbar excitability before, immediately, and 30 min, after real and sham applications of neurostimulation. Patients were randomized to a single session of either: pharyngeal electrical stimulation (PES), paired associative stimulation (PAS) or repetitive TMS (rTMS). Penetration-aspiration scores and bolus transfer timings were assessed before and after both real and sham interventions using videofluoroscopy., Results: Corticobulbar excitability of pharyngeal motor cortex was beneficially modulated by PES, PAS and to a lesser extent by rTMS, with functionally relevant changes in the unaffected hemisphere. Following combining the results of real neurostimulation, an overall increase in corticobulbar excitability in the unaffected hemisphere (P = .005, F1,17 = 10.6, ANOVA) with an associated 15% reduction in aspiration (P = .005, z = -2.79) was observed compared to sham., Conclusions: In this mechanistic study, an increase in corticobulbar excitability the unaffected projection was correlated with the improvement in swallowing safety (P = .001, rho = -.732), but modality-specific differences were observed. Paradigms providing peripheral input favored change in neurophysiological and behavioral outcome measures in chronic dysphagia patients. Further larger cohort studies of neurostimulation in chronic dysphagic stroke are imperative., (Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.)

Background and Study Aims: Oesophageal variceal haemorrhage is a devastating complication of portal hypertension (PHT). This study was done to determine the risk factors for re-bleeding within 5 days and mortality up to 6 weeks in patients with cirrhosis and acute variceal haemorrhage (AVH)., Patients and Methods: The study included 100 patients presenting with haematemesis and/or melena due to bleeding varices. All patients were subjected to full clinical assessment, routine laboratory investigations, calculation of the Child-Turcotte-Pugh (CTP) and model for end stage liver disease (MELD) scores, abdominal ultrasound and emergency upper gastrointestinal endoscopy. The patients were followed up since admission and up to 6 weeks for the occurrence of rebleeding (in the first 5days) and mortality (up to 6weeks) after the acute attack., Results: The patients were grouped into three groups: Group I: patients who survived more than 6 weeks following endoscopic management and did not rebleed during this period (75 patients). Group II: patients who died within 6 weeks of AVH (10 patients). Group III: patients who rebled or died within 5 days of AVH (15 patients). The mean MELD score was significantly higher in group II (18.29±0.66) and group III (18.73±0.89) as compared to group I (12.8±2.1) (p=0.001). Active bleeding at time of endoscopy was present in 8% of group I, 70% of group II and 53.3% of group III and the difference was statistically significant (p=0.003), while white nipple sign was present in 10.6% of group I, 90% of group II and 73.3% of group III and the difference was statistically significant (p=0.05). In conclusion high MELD score (>18), presence of active bleeding or white nipple sign at time of endoscopy are significant predictors for early rebleeding and mortality after AVH., (Copyright © 2013 Arab Journal of Gastroenterology. Published by Elsevier Ltd. All rights reserved.)

Background and Study Aims: In patients with chronic hepatitis C, the precise stage of hepatic fibrosis is the most important predictor of disease progression and it determines the need for antiviral therapy. Although liver biopsy is acknowledged as the gold standard for evaluating fibrosis, it is occasionally prone to sampling error and complications. We aimed to correlate an index of biochemical markers with histological features of fibrosis to predict hepatic fibrosis in patients with chronic hepatitis C virus, patients with combined hepatitis C virus and non-alcoholic steatohepatitis and those with non-alcoholic steatohepatitis, aiming to reduce the use of the liver biopsy., Patients and Methods: Out of those attending our out patient clinic for clinical, haematological, biochemical, virological, histological and ultrasonographic assessment prior to interferon therapy for hepatitis C virus, we enrolled 41 patients and grouped them according to histopathological examination of their liver biopsies into: Group I: 21 chronic hepatitis C virus patients as defined by positive 3rd generation ELISA; Group II: 20 patients with combined hepatitis C virus and NASH. We added a third group (Group III) of 15 patients having non alcoholic steatohepatitis as defined clinically, biochemically and through diagnostic percutanous liver biopsy. There were 33 male 23 female patients; 35 (62.5%) of them were from rural areas and 21 (37.5%) were from urban areas; the mean ages were 40.5±9, 46.6±7.7 and 42.13±11.06 in Group I, II and III respectively. Twenty apparently healthy individuals served as the control group. All the patients and the control group were submitted to full clinical history and examination, abdominal ultrasonography, CBC, liver biochemical profile and fibrosis biomarkers (apolipoprotein A1, haptoglobin, α2 marcoglobulin, GGT). Liver biopsy was done for suitable patients after taking a consent and the results of fibrosis seromarkers were compared with the results of liver biopsy using the Metavir scoring system. We also estimated patients' body mass index, fasting and post prandial blood glucose. We excluded patients with other causes of chronic liver disease and co-morbidities that could confound the results of the non-invasive markers adopted, including schistosomiasis which was excluded by serological test., Results: 43% of Group I and 40% of Group II had advanced fibrosis. None of Group III had advanced fibrosis; mild fibrosis was detected in 80% of them. γ-GT was found positively correlated to the degree of hepatic fibrosis in Groups I, II and III (r=0.667, 0.656 and 0.121, respectively) with P values of 0.001, 0.002, 0.668, respectively. α2 macroglobulin was found to be a reliable predictor of fibrosis (r=0.30, P=0.02) with ROC curve (area under the curve=0.70) best cutoff value 2.55g/L with sensitivity of 0.80 and specificity of 0.50. The results of haptoglobin were negatively related to the degree of hepatic fibrosis in Group I and II with ROC curve area under the curve of 0.33 and P value of 0.04. Significant direct correlation was seen in Group III (r=0.55, P=0.03), so by regression analysis, haptoglobin can be used as a good predictor for fibrosis in Group III (r=0.54, P=0.04). Apolipoprotein A1 has negative correlation to the stage of fibrosis in Groups I and II although the results were statistically insignificant. APRI index was found significantly directly correlated to the fibrosis stage and the grade of inflammation of all studied groups (r=0.57, P<0.01 and r=0.36, P<0.01, respectively) with a best cutoff value of 0.62, with sensitivity of 0.86 and specificity of 0.57. In patients with advanced fibrosis the best cutoff value was found to be 0.72 with sensitivity of 0.94 and specificity of 0.67. Modified APRI test showed AUC of 0.79 (P<0.01) with a best cutoff value of 0.067 at which sensitivity and specificity were 0.82 and 0.61, respectively., Conclusion: α2 macroglobulin, haptoglobin, apolipoprotein A1, APRI index and a modified APRI index, were found to be significant predictors of hepatic fibrosis and were reprocessed by stepwise logistic regression., (Copyright © 2009 Arab Journal of Gastroenterology. Published by Elsevier Ltd. All rights reserved.)

Objective: Pharyngeal stimulation can induce remarkable increases in the excitability of swallowing motor cortex, which is associated with short-term improvements in swallowing behaviour in dysphagic stroke patients. However, the mechanism by which this input induces cortical change remains unclear. Our aims were to explore the stimulus-induced facilitation of the cortico-bulbar projections to swallowing musculature and examine how input from the pharynx interacts with swallowing motor cortex., Methods: In 8 healthy subjects, a transcranial magnetic stimulation (TMS) paired-pulse investigation was performed comprising a single conditioning electrical pharyngeal stimulus (pulse width 0.2 ms, 240 V) followed by cortical TMS at inter-stimulus intervals (ISI) of 10-100 ms. Pharyngeal sensory evoked potentials (PSEP) were also measured over the vertex. In 6 subjects whole-brain magnetoencephalography (MEG) was further acquired following pharyngeal stimulation., Results: TMS evoked pharyngeal motor evoked potentials were facilitated by the pharyngeal stimulus at ISI between 50 and 80 ms (Delta mean increase: 47+/-6%, P < 0.05). This correlated with the peak latency of the P1 component of the PSEP (mean 79.6+/-8.5 ms). MEG confirmed that the equivalent P1 peak activities were localised to caudolateral sensory and motor cortices (BA 4, 1, 2)., Conclusions: Facilitation of the cortico-bulbar pathway to pharyngeal stimulation relates to coincident afferent input to sensorimotor cortex., Significance: These findings have mechanistic importance on how pharyngeal stimulation may increase motor excitability and provide guidance on temporal windows for future manipulations of swallowing motor cortex.

Objective: The excitability of corticobulbar projections to swallowing musculature undergoes remarkable long-term increases after short periods of pharyngeal stimulation. The aim of this study was to investigate the excitability of swallowing motor cortex following repetitive transcranial magnetic stimulation (rTMS)., Methods: Twelve healthy subjects were given 100 rTMS pulses over motor cortex at frequencies of 1, 5 and 10 Hz at an intensity of 80% threshold for corticobulbar activation. The excitability of the corticobulbar projection was assessed before and after rTMS and compared both to sham stimulation and to the corticospinal projection., Results: Stimulation at 5 Hz, but not 1 Hz, 10 Hz or sham stimulation increased the excitability of the corticobulbar projection to the pharynx, reaching a peak 60 min after rTMS (Delta increase: 65%, P=0.016). Excitability in the projection from the opposite hemisphere also increased, suggesting the presence of inter-hemispheric interactions, whereas excitability in the projection to thenar muscles was unchanged., Conclusions: Corticobulbar and corticospinal projections may differ in response to rTMS, implying differences in relative thresholds of inhibitory and excitatory elements in hand versus swallowing cortex., Significance: This might be a useful approach in the motor rehabilitation of dysphagic stroke patients who have damage to sensory projections to the swallowing cortex.

We present a method for the coregistration and topographic mapping of trans-cranial magnetic stimulation (TCMS) data on surface rendered images of the cortex, derived from Magnetic Resonance Images (MRI). We describe the TCMS procedure and the methods used to locate the TCM stimulation sites in the MRI coordinate system, and the algorithms needed to depict the TCMS distribution as a pseudocolour contour map on the cortical surface. The methods are validated using TCMS data from the hand (thenar) and leg (tibialis muscle). The methods used correctly depict the expected motor representations of each of these areas and we therefore propose that this technique may be used as a functional imaging tool in the investigation of cortical function in both normals and patients.

Background: Oropharyngeal dysphagia occurs in up to a third of patients presenting with a unilateral hemiplegic stroke, yet its neurophysiological basis remains unknown. To explore the relation between cortical motor function of swallowing and oropharyngeal dysphagia, mylohyoid, pharyngeal, and thenar electromyographic responses to stimulation of affected and unaffected hemispheres were recorded in dysphagic and non-dysphagic patients., Methods: The 20 patients studied had unilateral hemispheric stroke confirmed by computed tomography. Eight of them had associated swallowing difficulties. Electromyographic responses were recorded after suprathreshold transcranial magneto-electric stimulation of affected and unaffected hemispheres with a figure-of-eight coil., Findings: Stimulation of the unaffected hemisphere evoked smaller pharyngeal responses in dysphagic patients than in non-dysphagic patients (mean 64 microV, median 48, interquartile range 44-86 vs 118 microV, 81, 73-150) (p < 0.02). With stimulation of the affected hemisphere, the pharyngeal responses were smaller than for the unaffected hemisphere but similar between the two patient groups (26 microV, 0, 0-48 vs 54 microV, 0, 0-80). Dysphagic and non-dysphagic patients showed similar mylohyoid and thenar responses to stimulation of the unaffected hemisphere as well as to stimulation of the affected hemisphere-unaffected mylohyoid (269 microV, 239, 89-372 vs 239 microV, 163, 133-307), thenar (572 microV, 463, 175-638 vs 638 microV, 485, 381-764); affected mylohyoid (60 microV, 41, 0-129 vs 96 microV, 0, 0-195); thenar (259 microV, 258, 0-538 vs 451 microV, 206, 8-717)., Interpretation: The findings indicate that dysphagia after unilateral hemispheric stroke is related to the magnitude of pharyngeal motor representation in the unaffected hemisphere.

Seventy-three patients with headache underwent serum and cerebrospinal fluid (CSF) radioimmunoassays of follicle-stimulating hormone (FSH), luteinizing hormone (LH), cortisol and prolactin. Serum FSH showed significant increases in all headache patients while serum LH increased only in females. Such a rise of serum FSH and LH is attributed to disturbances of the sleep-wake cycle. On the other hand, serum cortisol was significantly decreased in the male headache patients, probably due to altered circadian rhythm. Serum prolactin remained within normal limits. CSF prolactin, FSH and LH showed detectable levels in all headache sufferers compared to undetectable levels in control subjects, while CSF cortisol was significantly reduced.