271 research outputs found

    Modifications Of Joint Mobility Range Induced By Eccentric Contraction

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    Dynamic eccentric contraction causes muscle damage consisting of: myofibrills disorganization, Z-lines disruption and cell membrane lesions. This damage is indirectly evidenced by a massive, delayed (4th-5th day) CK release in the serum. Negative work induces also a clinical condition defined as "Delayed Onset Muscle Soreness" (DaMS), characterized by delayed onset (8-24h) muscle pain, lowering in muscle pain threshold (24-4Bh), swelling of the exerted limb (72h). Stiffness and restricted range of movement in the joints related to the exerted muscles are also described, but the phenomena are less investigasted. The aim of this study was to evaluate the range of knee joint mobility before and after a standardized eccentric effort. Twelve healthy runners, aged 24-35 years, were examined. They performed a step-test (20' duration, 15 cycles/min), to exert the quadriceps femoris muscle of one side eccentrically. The day before the test, all the subjects underwent evaluation of Pressure Pain Threshold (PPT) of the exerted muscle and Passive Joint Mobility (PJM) of the knee. These evaluations were repeated immediately after the test and on the following 6 days; on the same days, the perceived pain was also measured by means of a force-transducer equipped with a 2.5 cm diameter rounded probe and a digital analyser (unit:Kg/f), applied on 12 pre-established spots on the quadriceps muscle surface; the mean of the 12 recordings was taken as, the final threshold value. PJM was measured by means of a manual goniometer on prone subjects; the exerted lower limb was moved from the rest position to the maxmal pain-free flexion; the degree at which the subject felt the minimum discomfort was recorded. Student's "ttest" for paired data was employed for statistical analysis. PPT showed a significant decrease after 24 and 4Bh in the exerted muscle, while pain reached maximum value at the 4Bh measurement. PJM showed a significant reduction 24-72h after the effort. DaMS is a complex phenomena, whose explanation is still unclear; particularly the temporal dissociation between symptoms and signs of muscle damage. The reduction of PJM has been attributed to edema of the connective tissue, due to the eccentric contraction stress. However the maximal thickness of the eccentrically exerted limb is usually found at 72h, while the reduction of PJM starts at 24h. The results of the present study show that the temporal pattern of PJM reduction is fairly similar to that of pain and hyperalgesia. This could suggest a reflex origin of the phenomenon, due to painful symptoms, through a tonic activation of antagonist muscles

    Vicious circles in contracts and in logic

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    Contracts are formal promises on the future interactions of participants, which describe the causal dependencies among their actions. An inherent feature of contracts is that such dependencies may be circular: for instance, a buyer promises to pay for an item if the seller promises to ship it, and vice versa. We establish a bridge between two formal models for contracts, one based on games over event structures, and the other one on Propositional Contract Logic. In particular, we show that winning strategies in the game-theoretic model correspond to proofs in the logi

    Debits and Credits in Petri Nets and Linear Logic

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    Exchanging resources often involves situations where a participant gives a resource without obtaining immediately the expected reward. For instance, one can buy an item without paying it in advance, but contracting a debt which must be eventually honoured. Resources, credits and debits can be represented, either implicitly or explicitly, in several formal models, among which Petri nets and linear logic. In this paper we study the relations between two of these models, namely intuitionistic linear logic with mix and Debit Petri nets. In particular, we establish a natural correspondence between provability in the logic, and marking reachability in nets

    Immunopathogenesis of sarcoidosis and risk of malignancy: a lost truth?

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    The hypothesis of a relationship between sarcoidosis and malignancy was firstly formulated in 1972 by Brincker. He documented an association of sarcoid reactions or sarcoidosis with 19 lymphomas and associated malignancies. Based on various epidemiological studies, for more than 20 years sarcoidosis has been considered as a condition at increased risk for cancer, particularly lymphoproliferative disorders. The existence of a sarcoidosis-lymphoma syndrome was therefore proposed, highlighting, as a potential mechanism, the uncontrolled lymphocyte proliferation and mitotic activity. A reduced ability to eliminate an antigen and chronic inflammation have been suggested as triggering events. Leading to a reduced tumor immune surveillance, a diminished myeloid dendritic cells (mDC) function, despite up-regulated co-stimulatory and maturation markers, was also raised as potential mechanism. However, some subsequent studies have questioned the presence of a close association between the two entities and have explained those previously published as the result of selection bias and misclassification. Recently, a Swedish population-based cohort study documented a significant overall excess incidence of cancer among sarcoidosis patients, especially those with multiple hospitalizations or admission in older age, emphasizing again a potential neoplastic risk. Therefore, currently, whether these patients have an increased risk of developing malignant lesions is still debated. Larger and unbiased studies are needed before drawing definite conclusions

    Correlation between Migraine Severity and Cholesterol Levels.

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    INTRODUCTION: Several studies have documented increased cardiovascular risk factors, particularly hypercholesterolemia, in the migraine population with respect to controls. However, no studies have investigated the possible relationship between headache severity parameters and lipid serum levels. METHODS: This study evaluated the lipid asset in 52 migraine patients (17 with and 36 without aura) before and after treatment with drugs for migraine prophylaxis for 3 months. RESULTS: High frequency (HF, ≥ 8/month) and intensity (HI, ≥ 5 Numeric Rating Score) vs. low frequency (LF, < 8/month) and intensity (LI, < 5) of crises were associated with significantly higher cholesterol levels, both total (TC, HF vs. LF, P < 0.0001; HI vs. LI, P < 0.0001) and LDL (LDL-c, HF vs. LF, P < 0.0001, and HI vs. LI, P < 0.0001). In treated patients, a significant decrease in number and intensity of crises was associated with a significant reduction of TC and LDL-c (P < 0.001). A direct linear correlation was also found between frequency and intensity of crises and lipid levels (TC/frequency, P < 0.0001; TC/intensity, P < 0.0001; LDL-c/frequency, P < 0.0001; LDL-c/intensity, P < 0.0001). No significant difference was found in the evaluated parameters for the subgroups of patients with and without aura. DISCUSSION: This study shows a significant positive association between migraine frequency and intensity with total and LDL cholesterol, demonstrating for the first time a significant reduction of these lipid parameters after migraine prophylaxis. However, in view of the retrospective design of the study and the small population size, these results should be considered as preliminary, to be confirmed by future prospective controlled trials

    Clinical features, histopathology and differential diagnosis of sarcoidosis

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    Sarcoidosis is a chameleon disease of unknown etiology, characterized by the growth of non-necrotizing and non-caseating granulomas and manifesting with clinical pictures that vary on the basis of the organs that are mainly affected. Lungs and intrathoracic lymph nodes are the sites that are most often involved, but virtually no organ is spared from this disease. Histopathology is distinctive but not pathognomonic, since the findings can be found also in other granulomatous disorders. The knowledge of these findings is important because it could be helpful to differentiate sarcoidosis from the other granulomatous-related diseases. This review aims at illustrating the main clinical and histopathological findings that could help clinicians in their routine clinical practice

    Ultramicronized palmitoylethanolamide reduces viscerovisceral hyperalgesia in a rat model of endometriosis plus ureteral calculosis: role of mast cells.

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    The effects of ultramicronized palmitoylethanolamide were evaluated on pain behaviours and markers of mast cell (MC) activity in 'a rat model of endometriosis plus ureteral calculosis (ENDO+STONE)-induced viscerovisceral hyperalgesia (VVH). Female Sprague-Dawley rats that underwent surgical induction of endometriosis were randomly assigned to receive active (ultramicronized palmitoylethanolamide 10 mg·kg-1 ·d-1, orally) or placebo treatment for 25 days. At day 21, they underwent ureteral stone formation and were video-recorded till day 25 to evaluate ureteral and uterine pain behaviours. At autopsy (day 25), ureteral condition and number and diameter of endometrial cysts were evaluated. The following were then measured: number and percentage of degranulating MCs, number of vessels, chymase, nerve growth factor (NGF), vascular endothelial growth factor (VEGF), and Flk-1 (VEGF receptor) in cysts, and NGF in dorsal root ganglia (DRG). Ultramicronized palmitoylethanolamide-treated vs placebo-treated rats showed significantly lower number, duration and complexity of ureteral crises, shorter duration of uterine pain, and smaller cyst diameter (0.0001 < P < 0.004); a significantly higher percentage of expelled stones (P < 0.0001); significantly lower MC number (P<0.01), vessel number (P< 0.01), chymase (P< 0.05), NGF (P<0.05), VEGF (P< 0.01), and Flk-1 (P< 0.01) expression in cysts and NGF expression in DRG (P< 0.01). In all animals, the global duration of ureteral crises correlated linearly and directly with cyst diameter, MC number and chymase in cysts, and NGF in cysts and DRG (0.02 < P < 0.0002). Ultramicronized palmitoylethanolamide significantly reduces VVH from ENDO+STONE, probably by modulating MC expression/activity in cysts, thus reducing central sensitization due to noxious signals from endometriotic lesions. The results suggest potential utility of the compound for VVH in clinics

    Frovatriptan versus almotriptan for acute treatment of menstrual migraine: analysis of a double-blind, randomized, cross-over, multicenter, Italian, comparative study

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    The objective of the study was to compare the efficacy and safety of frovatriptan and almotriptan in women with menstrually related migraine (IHS Classification of Headache disorders) enrolled in a multicenter, randomized, double-blind, cross-over study. Patients received frovatriptan 2.5 mg or almotriptan 12.5 mg in a randomized sequence: after treating 3 episodes of migraine in no more than 3 months with the first treatment, the patient was switched to the other treatment. 67 of the 96 female patients of the intention-to-treat population of the main study had regular menstrual cycles and were thus included in this subgroup analysis. 77 migraine attacks classified as related to menses were treated with frovatriptan and 78 with almotriptan. Rate of pain relief at 2 and 4 h was 36 and 53 % for frovatriptan and 41 and 50 % for almotriptan (p = NS between treatments). Rate of pain free at 2 and 4 h was 19 and 47 % with frovatriptan and 29 and 54 % for almotriptan (p = NS). At 24 h, 62 % of frovatriptan-treated and 67 % of almotriptan-treated patients had pain relief, while 60 versus 67 % were pain free (p = NS). Recurrence at 24 h was significantly (p < 0.05) lower with frovatriptan (8 vs. 21 % almotriptan). This was the case also at 48 h (9 vs. 24 %, p < 0.05). Frovatriptan was as effective as almotriptan in the immediate treatment of menstrually related migraine attacks. However, it showed a more favorable sustained effect, as shown by a lower rate of migraine recurrence
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