108 research outputs found
ABIOTIC DEGRADATION OF IODOSULFURON-METHYL-ESTER IN AQUEOUS SOLUTION
The abiotic degradation of iodosulfuron-methyl-ester was investigated under both alkaline and acidic
pH conditions in the dark, and results showed it to be a rather stable molecule in neutral or slightly
alkaline environments. Photochemical reactions were studied using a high-pressure mercury arc lamp,
and results showed that direct phototransformation is possible under normal environmental conditions
(ì > 290 nm). High-performance liquid chromatography (HPLC-UV and HPLC-MS) analyses were
used to identify the degradates and to study the kinetics of photodecomposition and hydrolysis. Five
main products of iodosulfuron-methyl-ester degradation were tentatively identified, and one of them
(4-methoxy-6-methyl-1,3,5-triazin-2-amine) was confirmed using an authentic standard. Among the
phototransformation mechanisms, photosubstitution of the iodide atom by a hydroxyl group,
photodissociation of the N-S bond, and photoassisted hydrolysis were observed. The quantum
efficiencies (multiwavelength quantum yield) of the photodegradation under different conditions were
determined, and values of 0.054 ( 0.02 (pH 9.6), 0.08 ( 0.02 (pH 7), and 0.044 ( 0.008 (pH 5.3)
were obtained
Correlazione tra anosognosia e rischio di cadute nel paziente cerebroleso postacuto
Introduzione
L\u2019anosognosia per l\u2019emiplegia \ue8 un disturbo neuropsicologico derivante da una lesione cerebrale che comporta l\u2019inconsapevolezza del deficit motorio. Il paziente inconsapevole del proprio deficit motorio \ue8 esposto a comportamenti talora pericolosi che potrebbero aumentare il rischio di caduta.
Lo studio si propone d\u2019identificare la presenza di anosognosia nei pazienti con lesione cerebrale in fase post-acuta, di valutare la possibile correlazione tra il grado di anosognosia e il deficit motorio acquisito e tra il grado di anosognosia e il rischio di caduta.
Materiali e metodi
E\u2019 stato condotto uno studio osservazionale su 16 pazienti con lesione cerebrale conseguente a ictus ischemico o emorragico in fase post-acuta. Ciascun paziente \ue8 stato sottoposto al Visual Analogue Test for Anosognosia for motor Impairment (VATAm) e valutato con la scala per l\u2019anosognosia per l\u2019emiplegia di Bisiach per l\u2019eventuale deficit di consapevolezza corporea, con la National Institute of Health Stroke Scale (NIHSS) per quantificare il deficit neurologico, con la Motricity Index Scale (MIS) per valutare le capacit\ue0 motorie e con la Morse Fall Scale per il rischio di caduta.
Per l'analisi statistica delle variabili oggetto dello studio \ue8 stato utilizzato un test non parametrico (Indice di correlazione di Spearman).
Risultati
Cinque dei 16 pazienti esaminati sono risultati anosognosici (31 %). Tre pazienti (60%) avevano una lesione emisferica destra, mentre due (40%) una lesione emisferica sinistra. Tutti i pazienti anosognosici avevano un deficit di sensibilit\ue0 e nel 40% dei casi anche eminattenzione.
Dall\u2019analisi statistica \ue8 emerso che nel campione esaminato l\u2019anosognosia \ue8 correlata alla gravit\ue0 del deficit motorio dell'arto superiore (MIS AS, p = 0,0014), ma non alla gravit\ue0 del deficit motorio dell'arto inferiore (MIS AI, p = 0,25). Inoltre l'anosognosia \ue8 risultata fortemente correlata al rischio di caduta (p < 0,0001), mentre il rischio di caduta \ue8 correlato al deficit motorio dell'arto superiore (MIS AS, p = 0,04), ma non dell'arto inferiore (MIS AI, p = 0,1).
Conclusioni
Da questi risultati emerge che la presenza di anosognosia aumenta il rischio di caduta indipendente-mente dalla gravit\ue0 del deficit motorio e ci\uf2 pu\uf2 influenzare negativamente l'outcome funzionale e allungare i tempi di degenza. In particolare, la correlazione tra il grado di anosognosia e la gravit\ue0 del deficit motorio dell\u2019arto superiore, ma non dell\u2019arto inferiore, suggerisce che i pazienti a maggior rischio di caduta sono quelli non consapevoli del deficit motorio, in grado per\uf2 di mobilizzarsi e, per il deficit dell'arto superiore, con ridotte reazioni anticipatorie e posturali di difesa
Ultrasound approach as integration of gross anatomy educational path for medical students
For physicians, the human body is the focus of investigation and intervention on a daily basis. It follows that the study of anatomy will continue to be essential to safe medical practice [1]. Anatomical education represents the cultural path that includes the best coexistence of old techniques, and avant-garde. Thus teachers forming future physicians are imposed to find new strategies for the acquisition of adequate professional competences [2]. The gross anatomy course attended by medical students was integrated by ultrasound training. Students were trained either in palpating and recognizing surface body-landmarks, or in the detection of different viscera. Their abilities were then evaluated. For three academic years (since 2009-10 to 2011-12), all the 262 students enrolled in the first year of Medicine and Surgery degree (“San Paolo” Hospital, Università degli Studi di Milano, Italy) participated. Of them, 16 volunteered in 2009-10, and 17 in each of the next two years, to preliminarily attend ultrasound training that their fellows would attend later. After this preliminary training, volunteers tutored their course fellows as peer tutors. All participants were either models or users. Each training presented three modules: 1) information about ultrasound scanning; 2) musculoskeletal system, major arterial and venous vessels, major nervous trunks, thyroid gland; 3) most thoracic, abdominal and pelvic viscera. Modules 2 and 3 were attended by small groups (6 students, assisted by 2 peer tutors). In module 2, topographical anatomy and subsequent recognition and palpation of surface bodylandmarks were also taught. The study of musculoskeletal system, major vessels and nerve trunks, and thyroid gland was supported by a multi-frequency probe equipped ultrasound machine. Thoracic, abdominal, and pelvic viscera were explored by a new generation pocket-sized ultrasound machine. Acquired skills were verified. The levels of expertise obtained by peer tutors and students were generally satisfactory. Students understood the importance of operative knowledge in human anatomical context. Anatomists found a valid method to consolidate the professionalizing quality of the topic
Miglioramento della resistenza e della performance muscolare mediante trattamento con onde d’urto defocalizzate
Scopo di questo studio \ue8 la valutazione degli effetti di un trattamento con onde d\u2019urto defocalizzate sull\u2019attivit\ue0 del muscolo scheletrico in termini di resistenza e di performance.
Sono stati reclutati 60 soggetti sani, 30 maschi e 30 femmine. 40 pazienti sono stati sottoposti al protocollo di intervento, mentre 20 hanno partecipato al gruppo di controllo, senza ricevere il trattamento con onde d\u2019urto.
Al termine di un ciclo di quattro sedute di onde d\u2019urto si \ue8 osservato un aumento dell\u2019Endurance Time e una diminuzione della Frequenza Cardiaca Massimale durante il test da sforzo a carico costante su cicloergometro.
A 12 settimane dalla fine del trattamento i valori della Frequenza cardiaca Massimale non hanno subito variazioni statisticamente significative, mentre quelli dell\u2019Endurance Time hanno subito un ritorno ai valori basali.
Per quanto riguarda la performance muscolare si \ue8 visto un miglioramento significativo alla valutazione T1, subito dopo la terapia con onde d\u2019urto, e alla valutazione T2, 12 settimane dopo l\u2019ultima seduta di onde d\u2019urto, rispetto alla valutazione iniziale a T0. Non \ue8 stata evidenziata una differenza statisticamente significativa tra i valori rilevati a T1e quelli a T2.
I risultati di questo studio suggeriscono che il trattamento con onde d\u2019urto defocalizzate pu\uf2 portare a un miglioramento dell\u2019attivit\ue0 del muscolo scheletrico in termini di performance e di resistenza muscolare senza provocare alcun tipo di danno ai tessuti.
Questi risultati aprono possibilit\ue0 di applicazione di questa metodica sia in ambito clinico (per esempio per il recupero funzionale dell\u2019amiotrofia ex non usu), sia in ambito sportivo
UEV-1 Is an Ubiquitin-Conjugating Enzyme Variant That Regulates Glutamate Receptor Trafficking in C. elegans Neurons
The regulation of AMPA-type glutamate receptor (AMPAR) membrane trafficking is a key mechanism by which neurons regulate synaptic strength and plasticity. AMPAR trafficking is modulated through a combination of receptor phosphorylation, ubiquitination, endocytosis, and recycling, yet the factors that mediate these processes are just beginning to be uncovered. Here we identify the ubiquitin-conjugating enzyme variant UEV-1 as a regulator of AMPAR trafficking in vivo. We identified mutations in uev-1 in a genetic screen for mutants with altered trafficking of the AMPAR subunit GLR-1 in C. elegans interneurons. Loss of uev-1 activity results in the accumulation of GLR-1 in elongated accretions in neuron cell bodies and along the ventral cord neurites. Mutants also have a corresponding behavioral defect—a decrease in spontaneous reversals in locomotion—consistent with diminished GLR-1 function. The localization of other synaptic proteins in uev-1-mutant interneurons appears normal, indicating that the GLR-1 trafficking defects are not due to gross deficiencies in synapse formation or overall protein trafficking. We provide evidence that GLR-1 accumulates at RAB-10-containing endosomes in uev-1 mutants, and that receptors arrive at these endosomes independent of clathrin-mediated endocytosis. UEV-1 homologs in other species bind to the ubiquitin-conjugating enzyme Ubc13 to create K63-linked polyubiquitin chains on substrate proteins. We find that whereas UEV-1 can interact with C. elegans UBC-13, global levels of K63-linked ubiquitination throughout nematodes appear to be unaffected in uev-1 mutants, even though UEV-1 is broadly expressed in most tissues. Nevertheless, ubc-13 mutants are similar in phenotype to uev-1 mutants, suggesting that the two proteins do work together to regulate GLR-1 trafficking. Our results suggest that UEV-1 could regulate a small subset of K63-linked ubiquitination events in nematodes, at least one of which is critical in regulating GLR-1 trafficking
No evidence of association between prothrombotic gene polymorphisms and the development of acute myocardial infarction at a young age
Background : we investigated the association between 9 polymorphisms of genes encoding hemostasis factors and
myocardial infarction in a large sample of young patients chosen because they have less coronary atherosclerosis than
older patients, and thus their disease is more likely to be related to a genetic predisposition to a prothrombotic state Methods and Results : this nationwide case-control study involved 1210 patients who had survived a first myocardial infarction at an age of 45 years who underwent coronary arteriography in 125 coronary care units and 1210 healthy subjects matched for age, sex, and geographical origin. None of the 9 polymorphisms of genes encoding proteins involved in coagulation (G-455A -fibrinogen: OR, 1.0; CI, 0.8 to 1.2; G1691A factor V: OR, 1.1; CI, 0.6 to 2.1; G20210A factor II: OR, 1.0; CI, 0.5 to 1.9; and G10976A factor VII: OR, 1.0; CI, 0.8 to 1.3), platelet function (C807T
glycoprotein Ia: OR, 1.1; CI, 0.9 to 1.3; and C1565T glycoprotein IIIa: OR, 0.9; CI, 0.8 to 1.2), fibrinolysis (G185T factor XIII: OR, 1.2; CI, 0.9 to 1.6; and 4G/5G plasminogen activator inhibitor type 1: OR, 0.9; CI, 0.7 to 1.2), or homocysteine metabolism (C677T methylenetetrahydrofolate reductase: OR, 0.9; CI, 0.8 to 1.1) were associated with an increased or decreased risk of myocardial infarction Conclusions : this study provides no evidence supporting an association between 9 polymorphisms of genes encoding proteins involved in hemostasis and the occurrence of premature myocardial infarction or protection against it
Balance and mobility assessment for ruling-out the peripheral neuropathy of the lower limbs in older adults
The peripheral neuropathy of the lower limbs (PNLL) is an important cause of balance and mobility impairment in older adults. The nerve conduction study (NCS) is the gold standard for PNLL diagnosis. Aim of this work is to establish the sensitivity (Sn) and the speci\ufb01city (Sp) of the balance and mobility examination for the PNLL in older adults. This study consecutively recruited 72 participants (>65 years) who accessed to the clinical neurophysiology outpatient clinic for suspected PNLL. Participants were given the NCS and four clinical tests. Mobility was evaluated by the Timed Up and Go (TUG) test, the Performance Oriented Mobility Assessment (POMA) and the de Morton Mobility Index (DEMMI). In addition the Clinical Evaluation of Static Upright Stance (CELSIUS) scale was developed for a selective evaluation of static balance. Based on the NCS, 36% of participants had PNLL. The CELSIUS scale (cutoff: 19.5/24), the TUG test (cutoff: 9.6 s) and the DEMMI scale (cutoff: 17.5/19) have high Sn (0.92 -- 0.96), but low Sp (0.28 -- 0.43) for the PNLL in the older adult. POMA scale (cutoff: 14.5/16) has low Sn (0.73), but acceptable Sp (0.85). In addition, CELSIUS, DEMMI and TUG negative likelihood ratios are 0.13, 0.17 and 0.12, respectively.
Balance and mobility examination have high sensitivity for PNLL. CELSIUS score > 19/24, DEMMI score > 17/19 or TUG time ::: 9.6 s substantially reduce PNLL likelihood. These clinical measures are thus recommended for ruling-out PNLL in the older adult
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