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101.
ObjectiveTo explore the effect of variable durations of stretching on neural function, pain, and algometric pressure in patients with chronic myofascial pain syndrome.DesignRandomized controlled trial.PatientsA total of 100 participants diagnosed with chronic myofascial pain syndrome were randomly assigned to a control group or 1 of 3 intervention groups.MethodsThe 3 experimental groups received different durations of cervical spine stretching: 15, 30 or 60 s. The control group did not stretch. Primary outcome measures included peak-to-peak somatosensory-evoked potential for dermatomes C6, C7 and C8. Secondary outcome measures included central somatosensory conduction time (N13–N20), pain intensity, and pressure-pain threshold algometric measurements. All outcome measures were assessed immediately after and 2 h after the treatment session.ResultsPost hoc analysis indicated that stretching for 60 s significantly decreased the dermatomal amplitude for C6, C7 and C8 (p < 0.001) and significantly increased the central conduction time, indicating negative effect (p < 0.001). Stretching for 30 and 60 s resulted in greater improvement in pain intensity and algometric pressure than stretching for 15 s or no stretch (control) p < 0.001.ConclusionStretching cervical muscles involved in chronic myofascial pain syndrome for 30 s was optimal in achieving stretching benefits and minimizing the negative effects on the neural function of the involved nerve roots and central nervous system.LAY ABSTRACTThis study measured the effect of different durations of stretching (15 s, 30 s, 60 s and no stretching) of the muscles around the neck and shoulders in 100 participants with chronic myofascial pain syndrome. The outcome measures assessed the effect on neural function. The results show that stretching for 30 s was the optimal time, for achieving stretching benefits and minimizing the negative effects on the neural function of the involved nerve roots and central nervous system. Stretching for a longer time negatively affected the neural function, but decreased the pain level, while stretching for a shorter time did not achieve the optimal muscle length after stretching.Key words: stretching, randomized controlled trial, cervical, neural function, optimal stretching duration

Chronic myofascial pain syndrome (CMPS) is a syndrome of musculoskeletal pain that is typically linked to myofascial trigger points (MTrP) (1, 2). CMPS is mostly prevalent in muscles that are consistently active against gravity or muscles that are essential in repetitive activities, such as the head, neck, shoulders, hips and low back muscles (3). The postural muscles that most commonly tend to be shortened are the upper trapezius and levator scapulae, resulting in limited neck mobility (4) and, due to the continuous demand on these muscles to maintain an upright posture, there appears to be a strong justification for stretching them.Current approaches to the management of CMPS include pharmacological and non-pharmacological interventions (57). Among the non-pharmacological approaches, many studies have supported stretching exercises as a beneficial intervention to treat CMPS (811). Overall, while the results of these studies are not specific to stretching alone, stretching exercises appear to be an important component of CMPS management. While the benefits of stretching are known, controversy remains about the stretching parameters needed to achieve a particular goal or treatment outcome. In clinical practice, multiple stretching techniques are used; nevertheless, there is no evidence-based agreement on the most effective parameters. One of the parameters that might affect treatment outcome the most is stretching duration; however, to date, there is a little agreement about the optimal duration of stretching (1215).Of interest, comparison and subsequent conclusions about appropriate stretching times are based mainly on mechanical factors, such as range of motion and flexibility, while ignoring the neural adverse mechanical tension that may be created during sustained stretching exercises. According to the literature (1618), stretching induces neural tension that may adversely affect the central nervous system and nerve root function, due to the absence of the perineurium, which is the primary load-carrying structure. Thus, safe or unsafe limits of nerve elongation are not well established, despite several basic scientific and clinical studies (19). It is thought that the same phenomenon of tissue loading is applicable to the nervous system. The literature indicates that the most offensive: the most structure damaging postural loading of the central nervous system and related structures occurs in any procedure or position requiring spinal flexion (20).Consequently, the current study aimed to determine whether increased longitudinal strain and stress on the spinal cord and nerve roots from continuous stretching exercises could subtly impair neural function. The study hypothesis is that there is a duration threshold, beyond which adverse neural function will be apparent, resulting in a reduction in either or both latency and amplitudes of evoked potentials.  相似文献   
102.
Bradycardia is rare in children and may be asymptomatic or cause fatigue or discomfort leading to syncope. It may be a warning sign of underlying pathology. A check-up for a cardiac or extra-cardiac organic cause should be performed. We report the case of an 8-year-old child admitted to the emergency room for bradycardia with a sino-atrial block that caused syncope. The assessment has objectified a brain tumor. We will discuss the different mechanisms that can explain the occurrence of bradycardia during a brain tumor, and the specificities of the management.  相似文献   
103.
In the present era, there are many efforts trying to face the emerging and successive waves of the COVID-19 pandemic. This has led to considering new and unusual targets for SARS CoV-2. 2′-O-Methyltransferase (nsp16) is a key and attractive target in the SARS CoV-2 life cycle since it is responsible for the viral RNA protection via a cap formation process. In this study, we propose a new potential inhibitor for SARS COV-2 2′-O-methyltransferase (nsp16). A fragment library was screened against the co-crystal structure of the SARS COV-2 2′-O-methyltransferase complexed with Sinefungin (nsp16 – PDB ID: 6WKQ), and consequently the best proposed fragments were linked via a de novo approach to build molecule AP-20. Molecule AP-20 displayed a superior docking score to Sinefungin and reproduced the key interactions in the binding site of 2′-O-methyltransferase. Three molecular dynamic simulations of the 2′-O-methyltransferase apo structure and its complexed forms with AP-20 and Sinefungin were performed for 150 nano-seconds to provide insights on the dynamic nature of such setups and to assess the stability of the proposed AP-20/enzyme complex. AP-20/enzyme complex demonstrated better stability for the ligand–enzyme complex compared to Sinefungin in a respective setup. Furthermore, MM-PBSA binding free energy calculations showed a better profile for AP-20/enzyme complex compared to Sinefungin/enzyme complex emphasizing the potential inhibitory effect of AP-20 on SARS COV-2 2′-O-methyltransferase. We endorse our designed molecule AP-20 to be further explored via experimental evaluations to confront the spread of the emerging COVID-19. Also, in silico ADME profiling has ascribed to AP-20 an excellent safety and metabolic stability profile.

The identification of AP-20 as a potential SARS COV-2 2′-O-methyltransferase inhibitor: fragment-based screening approach and MM-PBSA calculations.  相似文献   
104.
Objectives:To assess the sex hormone levels in young Saudi female migraineurs during a migraine attack and during pain-free periods and compare them with control subjects.Methods:A case-control study involving 14 Saudi female migraineurs and 21 control subjects was conducted between December 2019 and March 2020. Demographic and disease history data were collected through participant interviews. Blood samples were drawn during the migraine attack and pain-free periods.Results:Follicular (30.00±19.60; p<0.001) and luteal (39.79±11.45; p=0.037) estrogen levels were significantly higher in patients with non-menstrual related migraine (NMM), while luteal testosterone levels (1.10±0.31; p=0.023) were significantly higher in patients with menstrually related migraine (MM). Body mass index (BMI) was higher in patients with NMM (25.77±6.53; p=0.013), and it was found to be associated with follicular estrogen (p=0.016), progesterone (p=0.018), and pain intensity (p=0.042). Luteal estrogen level was significantly lower (13.96±7.88; p=0.036) in patients with luteal onset of attack.Conclusion:High estrogen levels were found to mediate NMM, their effect being more pronounced with increase in BMI; whereas low luteal estrogen levels mediated MM. Young females with MM might have high luteal testosterone levels, and a compensatory protective role could be surmised accordingly.  相似文献   
105.
Surgical vitiligo treatment is suggested for recalcitrant small stable lesions. One of the limitations of this approach is the presence of large lesions. The donor site should be designed to be hidden without previous or present lesions; this limits donor sites. Aim of the study was to clinically and histopathologically evaluate donor areas 3 months and 1 year after Thiersch grafting (TG) and suction blister epithelial grafting (SBEG). Forty patients with stable vitiligo were equally divided into two groups before TG and SBEG. In each patient, the donor site was clinically and histopathologically evaluated after 3 months and 1 year. After 3 months in Group I, hyperpigmentation, mixed pigmentation with atrophic scarring, hyperpigmentation with hypertrophic scarring, erythema, and tough skin were detected in 10%, 50%, 10%, 10%, and 20% of cases, respectively. The condition improved with time leaving, leaving tough skin in all cases after 1 year. In Group II, hyperpigmentation was observed in all patients after 3 months and disappeared completely after 1 year. Histologically, biopsies taken 3 months after TG, showed increased basal pigmentation with dermal changes mimicking scar tissue in 92.5% of cases. Collagen homogenization of and fragmented elastic tissue were reported in all cases. Biopsies showed the same features after 1 year. In the SBEG group, biopsies revealed only basal hyperpigmentation that disappeared after 1 year in all patients. We concluded that SBEG is a scarless operation and regrafting from the same area can be performed. This is in contrast to TG, which is considered a scarring operation, and wherein the donor site cannot be reused for grafting.  相似文献   
106.
AIM: To identify alterations in genes and molecular functional pathways in esophageal cancer in a high incidence region of India where there is a widespread use of tobacco and betel quid with fermented areca nuts. METHODS: Total RNA was isolated from tumor and matched normal tissue of 16 patients with esophageal squamous cell carcinoma. Pooled tumor tissue RNA was labeled with Cy3-dUTP and pooled normal tissue RNA was labeled with Cy5-dUTP by direct labeling method. The labeled probes were hybridized with human 10K cDNA chip and expression profiles were analyzed by Genespring GX V 7.3 (Silicon Genetics). RESULTS: Nine hundred twenty three genes were differentially expressed. Of these, 611 genes were upregulated and 312 genes were downregulated. Using stringent criteria (P ≤ 0.05 and ≥ 1.5 fold change), 127 differentially expressed genes (87 upregulated and 40 downregulated) were identified in tumor tissue. On the basis of Gene Ontology, four different molecular functional pathways (MAPK pathway, G-protein coupled receptor family, ion transport activity, and serine or threonine kinase activity) were most significantly upregulated and six different molecular functional pathways (structural constituent of ribosome, endopeptidase inhibitor activity, structural constituent of cytoskeleton, antioxidant activity, acyl group transferase activity, eukaryotic translation elongation factor activity) were most significantly downregulated. CONCLUSION: Several genes that showed alterations in our study have also been reported from a high incidence area of esophageal cancer in China. This indicates that molecular profiles of esophageal cancer in these two different geographic locations are highly consistent.  相似文献   
107.
Objective:We aimed to investigate whether individuals with first-episode psychosis (FEP) receiving extended early intervention (EI) were less likely to experience suicidal ideation and behaviors than those transferred to regular care after 2 years of EI. Another objective was to examine the 5-year course of suicidality in FEP.Methods:We conducted a secondary analysis of a randomized controlled trial where 220 patients were randomized after 2 years of EI to receive extended EI or regular care for the subsequent 3 years. Suicidality was rated using the Brief Psychiatric Rating Scale. Linear mixed model analysis was used to study time and group effects on suicidality.Results:Extended EI and regular care groups did not differ on suicidality. There was a small decrease in suicidality over time, F(7, 1038) = 1.84, P = 0.077, with an immediate sharp decline within a month of treatment, followed by stability over the remaining 5 years. Patients who endorsed suicidality at entry (46.6%) had higher baseline positive, negative, and depressive symptoms. The 5-year course fell in 3 groups: never endorsed suicidality (33.9%), endorsed suicidality at low-risk levels (43.1%), and endorsed high-risk levels (23.0%). The high-risk group had a higher proportion of affective versus nonaffective psychosis diagnosis; higher baseline positive and depressive symptoms; higher 5-year mean depression scores, and fewer weeks of positive symptom remission over the 5-year course.Conclusions:The first month of treatment is a critical period for suicide risk in FEP. Although early reductions in suicidality are often maintained, our findings make the case for sustained monitoring for suicide risk management.  相似文献   
108.
109.
ObjectiveTo assess the influence of glutathione S-transferases M1 and T1 (GSTM1 and T1) genotype on the risk of bladder cancer in patients with urinary bilharziasis.Materials and methodsThis study was designed as a case-control study that involved 60 individuals who were enrolled into 3 equal groups. The first one included patients with bilharzial bladder cancer, the second one had those with nonmalignant urinary bilharziasis, and the last one was the control group. All of the participants were adult males, nonsmokers, and with matched ages. All of them underwent an assessment of the serum level of the total GST concentration and the polymerase chain reaction (PCR) was used for determination of the GSTM1 and T1 genotypes.ResultsThe lower most GST enzyme concentration was reported in patients with bilharzial bladder cancer (26 ± 4.4 ng/ml) with significant difference between it and that of the second group (36.8 ± 4.1 ng/ml, P < 0.05) and that of the controls (40.4 ± 4 ng/ml, P < 0.005). The PCR results have demonstrated that the frequency of combined GSTM1 and T1 genes deletion (M1–ve T1–ve) was significantly higher in cases of bladder cancer (40%) than those of the controls (5%, P < 0.005) and those of the second group (10%, P < 0.05). The unconditional logistic regression test revealed that patients with urinary bilharziasis and combined GSTM1 and T1 genes deletion are at a significant risk for malignant transformation (OR = 6.3, P < 0.05).ConclusionsPatients with urinary bilharziasis and GSTM1–ve and T1–ve genes might be at increased risk of bladder cancer. However, larger studies are needed for confirmation of these results.  相似文献   
110.
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