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131.

Purpose

It has been demonstrated that the semitendinosus tendon can regenerate after being harvested in its whole length and thickness for anterior cruciate ligament (ACL) reconstruction. Ultrasound studies and guided biopsies of the regenerated tendon have shown compatibility and resembling features of the normal tendon. The question is if this neo-tendon is biologically and functionally adequate for re-use?

Methods

Two randomised groups of 150 volunteers were followed up for two years after harvesting the semitendinosus only (25) or the semitendinosus and gracilis tendons (25) in ACL reconstruction. The patients were followed up with clinical and ultrasound examinations, biopsies and histological tests. Surgical exploration was done in three patients for macroscopic verification. The injected arteries of four lower limbs were dissected and the tendon’s arterial supplies were examined.

Results

Seventy-two percent of the cases showed regeneration of the semitendinosus tendons. The neotendons were inserted mostly below the knee joint (83.3 %) where they had fused with the gracilis tendon, and above the joint (60 %) when the gracilis was harvested as well. The isokinetic strength of the hamstrings and quadriceps was not significantly diminished on the operated side. A macroscopic and histological analysis of the regenerated tendons demonstrates close resemblance to normal anatomy, with focal areas of fibrosis. In one patient the regenerated tendon was used for medial patellofemoral ligament reconstruction.

Conclusion

The semitendinosus muscle can recover and the tendon has great potential to regenerate after harvesting for ACL reconstruction. Our data suggest that the regenerated tendons could be used for iterative ligament reconstruction.  相似文献   
132.
We investigated the existence of a temporal association between age at initiation of cannabis use and age at onset of psychotic illness in 997 participants from the 2010 Survey of High Impact Psychosis (SHIP) in Australia. We tested for group differences in age at onset of psychotic illness and in the duration of premorbid exposure to cannabis (DPEC). Analyses were repeated in subgroups of participants with a schizophrenia-spectrum disorder (SSD), a diagnosis of lifetime cannabis dependence (LCD), and a comorbid SSD/LCD diagnosis. The association between age at initiation of cannabis use and age at onset of psychotic illness was linear and significant, F(11, 984) = 13.77, P < .001, even after adjusting for confounders. The effect of age at initiation of cannabis use on DPEC was not significant (mean duration of 7.8 years), and this effect was similar in participants with a SSD, LCD, and comorbid SSD/ LCD diagnosis although a shift toward shorter premorbid exposure to cannabis was noted in the SSD/LCD subgroup (mean duration of 7.19 years for SSD/LCD). A temporal direct relationship between age at initiation of cannabis use and age at onset of psychotic illness was detected with a premorbid exposure to cannabis trend of 7–8 years, modifiable by higher severity of premorbid cannabis use and a diagnosis of SSD. Cannabis may exert a cumulative toxic effect on individuals on the pathway to developing psychosis, the manifestation of which is delayed for approximately 7–8 years, regardless of age at which cannabis use was initiated.Key words: cannabis, psychosis, schizophrenia, age at onset, causality, DIP, SHIP  相似文献   
133.
Throughout its duration, the coronavirus disease 2019 (COVID-19) pandemic has been affecting lives worldwide and has had a sizeable impact on mental health, particularly for those who already suffer from a chronic illnesses. Depression, Anxiety and Stress (DAS) are common psychiatric comorbidities in inflammatory bowel disease (IBD) patients. This study aims to determine the prevalence and risk factors for moderate and severe symptoms of DAS in IBD patients have been undergoing intravenous biological therapy (IvBTh) during the COVID-19 pandemic. The study was conducted between September 1st and November 30th, 2020 at the Clinical Center of Montenegro-IBD unit, where all patients from Montenegro received the registered IvBTh. This case control study consists of 94 IBD patients that completed a validated questionnaire Depression, Anxiety and Stress Score-21 (DASS-21). A total of 59 patients received tumor necrosis factor alpha inhibitors (anti-TNF therapy), while 35 received anti-integrin therapy. After we calculated the DASS-21 score, we divided the patients into two groups: those who had moderate and severe symptoms (if they had any of the mentioned DASS-21 subscale score above limit for moderate or more severe symptoms: DASS-21 Depression, higher than 14; DASS-21 Anxiety, higher than 10 and DASS-21 Stress, higher than 19) and those who did not have significant symptoms (DASS-21 subscale score did not exceed the limit). We also examined demographic data, data on IBD characteristics and COVID-19 data and their impact on mental disorders. Standard statistical processing tests were used to identify risk factors for examined mental disorders. Following the DASS-21 criteria, we diagnosed the least moderate depression in 19.1%, anxiety in 14.9% and stress in 20.2% patients. The multivariate analysis indicated there to be a statistically significant relation of being higher at risk of developing depression, anxiety and stress when suffering from an active form of IBD (OR 6.487; 95% Cl 1.220–34.500, P = 0.028). Almost one third (30.9%) of patients have at least one of the examined mental disorders during the COVID-19 pandemic. Particular attention and efforts must be better focused on patients who suffer from an active form of IBD during the ongoing COVID-19 pandemic.  相似文献   
134.
135.
Several functional MR imaging studies evaluating the lateralisation of linguistic functions in patients who underwent Wada testing have been reported. There is extensive variance in the Laterality index (LI) calculation across the studies, and the optimal calculation method remains unclear. We attempted to calculate the LI in different ways in the same subjects, in order to find the LI calculation method with the highest correlation to the Wada test. Fifteen patients (10 females, 5 males) suffering from medically intractable temporal lobe epilepsy (TLE) (12 left, 3 right) were admitted for the study. The patients underwent a standardized bilateral intracarotid short-acting barbiturate test. Language testing included spontaneous speech, oral comprehension, reading, object and picture naming, and repetition. All the tasks were scored separately in order to increase the possibility of correlation between Wada and LI. A silent phonemic verbal fluency task (VFT) was used as a language paradigm for functional measurement. Regions of interest (ROIs), with a known association with language function (Broca’s area, the lateral prefrontal cortex, etc.), were defined. First, the LIs were calculated from the ROIs using a previously reported method (simple suprathreshold count). Next, we used several new methods of LI calculation (t–weighting of voxels, methods independent of the choice of the statistical threshold, etc.) The most significant correlation with Wada was proven in the LIs that were evaluated from Broca’s area (up to R = 0.94, P = 1 × 10−7). However, the new LI calculation methods used in the present study did not produce a statistically significant benefit in comparison to previously reported methods.  相似文献   
136.
137.
In order to investigate new potential therapeutically active agents, we investigated the biological properties of two small libraries of quinoxalinones and 1,4‐benzoxazin‐2‐ones. The results obtained showed that compounds 5 , 9–11 have good cytotoxic activity against HeLa cells where the lowest IC50 value (10.46 ± 0.82 μM/mL) was measured for compound 10 . Additionally, the most active compounds ( 5 , 9 – 11 ) showed much better selectivity for MRC‐5 cells (up to 17.4) compared to cisplatin. In vitro evaluation of the inhibition of the enzyme α‐glucosidase showed that compounds 10 and 11 exert significant inhibition of the enzyme at 52.54 ± 0.09 and 40.09 ± 0.49 μM, respectively. Competitive experiments with ethidium bromide (EB) indicated that all tested compounds have affinity to displace EB from the EB‐DNA complex through intercalation, suggesting good competition with EB (Ksv = (3.1 ± 0.2), (5.1 ± 0.1), (5.6 ± 0.2), and (6.3 ± 0.2) × 103 M?1). A molecular docking study was also performed to better understand the binding modes and to conclude the structure–activity relationships of the synthesized compounds.
  相似文献   
138.

Objective

To identify possible predictors of post-cessation weight gain in smoking abstainers.

Patients and methods

A sample of 607 successful abstainers seen at the Centre for Tobacco-Dependent in Prague, Czech Republic, between 2005 and 2010, was included in this analysis. This sample was followed up for 1 year and included 47.9% women (N = 291) with the mean age of 48 years (18–85).

Findings

Post-cessation weight gain occurred in 88.6% of the 607 abstainers. The mean weight gain after one year post-quit was 5.1 kg (95% confidence interval 4.7–5.5 kg). Baseline characteristics associated with increased weight gain included a higher baseline smoking rate (p < 0.001), more severe cigarette dependence (p = 0.003), less physical activity (p = 0.008), and a report of increased appetite on the baseline assessment of withdrawal symptoms (p < 0.001).

Conclusions

Smokers who are more dependent and have minimal physical activity are at increased risk for post-cessation weight gain. For these smokers, incorporating interventions targeting the weight issue into tobacco dependence treatment is recommended. Further research should be done to identify reasons for this important quitting complication.  相似文献   
139.
Secondary-cast aluminum alloys have increasing industrial applications. Their biggest deficiency is their impurity content, especially Fe, which has low solubility in Al and almost all the content creates intermetallic phases. This work examines the effect of higher Fe content on the microstructure and properties of A356.0 alloy. At the same time, no other possibility existed to affecting the brittleness of the formation of the β phases. The calculation of Fecrit, ratio of Mn/Fe, quantitative and computed tomography analysis of porosity and Fe plate-like phases, measurement of mechanical and fatigue properties, and fractography analysis were performed in this study. The results show that gravity die casting into a sand mold, and the non-usage of Mn addition or heat treatment, do not have a negative effect on increasing the size of the Fe-rich plate-like phases. The longest Fe-rich phases have limited the pore growth and ratios, but their higher thickness led to greater porosity formation. The mechanical and fatigue properties correlate with the Fecrit level and the highest were for the experimental alloy with 0.454 wt.% of Fe. The experimental results confirmed the fact that if the Fe plate-like phases have a length of up to 50 µm, the fatigue properties depend more on the size of porosity. If the length of the Fe needles is more than 50 µm, then the properties are mainly affected by the length of these Fe phases.  相似文献   
140.
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