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21.
Idor Svensson Linda Fälth Bengt Persson Staffan Nilsson 《Psychiatry, Psychology and Law》2017,24(3):440-457
The aim of the present study was to investigate the effect of a short period, 15 sessions, of reading interventions in a sample of adult forensic psychiatric patients: 61 patients with decoding difficulties – 44 in the experimental group and 17 in the comparison group – with an average age of 31.6 participated. Of these, 36% were female, and 29% had an immigrant background. The participants carried out a battery of reading tests. The results in the experimental group showed a medium effect size (d = .36 to .76) on all reading tests between pre- and post-test. The comparison group, however, showed no gain at all between the test occasions. The results indicate that a proportionally low reading intervention effort produces improvement in reading. This study discusses the importance of including reading assessment and offering remediation in order to reach optimal future social adjustment for patients in forensic clinics. 相似文献
22.
Anders G. Liss Anne Lagerström Karin Hultin Jäderlund Staffan Bowald Fredrik W. af Ekenstam Roland Flink Mikael Wiberg 《Journal of plastic surgery and hand surgery》2013,47(4):403-409
Injury to a sensory nerve often results in a clinically poor long term outcome, possibly as a result of the extensive loss of neurons within the dorsal root ganglia (DRG), which has been shown in several experimental studies. This loss is possibly caused by interruption of the sensory input and axonal transport in the damaged afferent nerve. To investigate the importance of sensory afferent input into a nerve a pulsed electric stimulation was applied on the proximal part of the superficial radial nerve after transsection and microsurgical repair. The purpose was to simulate nerve impulses and thereby mask the severity of the injury. To test this hypothesis a pilot study was undertaken in eight cats. The neuronal tracer showed that the median neuronal loss was 38% of the neurons of the dorsal root ganglia that received afferents from the nerve investigated, which corresponds to the figure in a previous study in which electric stimulation was not used. Artificial sensory stimulation during regeneration in a transsected and repaired peripheral nerve therefore does not seem to reduce neuronal loss. 相似文献
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Zhu Qiao Edwin R. Lampugnani Xin-Fu Yan Ghazanfar Abbas Khan Wuan Geok Saw Patrick Hannah Feng Qian Jacob Calabria Yansong Miao Gerhard Grüber Staffan Persson Yong-Gui Gao 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(11)
Cellulose is synthesized by cellulose synthases (CESAs) from the glycosyltransferase GT-2 family. In plants, the CESAs form a six-lobed rosette-shaped CESA complex (CSC). Here we report crystal structures of the catalytic domain of Arabidopsis thaliana CESA3 (AtCESA3CatD) in both apo and uridine diphosphate (UDP)-glucose (UDP-Glc)–bound forms. AtCESA3CatD has an overall GT-A fold core domain sandwiched between a plant-conserved region (P-CR) and a class-specific region (C-SR). By superimposing the structure of AtCESA3CatD onto the bacterial cellulose synthase BcsA, we found that the coordination of the UDP-Glc differs, indicating different substrate coordination during cellulose synthesis in plants and bacteria. Moreover, structural analyses revealed that AtCESA3CatD can form a homodimer mainly via interactions between specific beta strands. We confirmed the importance of specific amino acids on these strands for homodimerization through yeast and in planta assays using point-mutated full-length AtCESA3. Our work provides molecular insights into how the substrate UDP-Glc is coordinated in the CESAs and how the CESAs might dimerize to eventually assemble into CSCs in plants.Cellulose, a linear homopolymer of d-glucopyranose linked by β-1,4-glycosidic bonds, is the major structural component of the cell walls of plants, oomycetes, and algae and constitute the most abundant biopolymer on Earth (1). Cellulose is synthesized by cellulose synthases (CESAs) that belongs to the glycosyltransferase GT-2 superfamily (1, 2). In land plants, cellulose is produced at the plasma membrane by six-lobed rosette-shaped CESA complexes (CSCs) where each CESA is thought to synthesize one cellulose chain (3). The precise number of CESAs per CSC is unresolved but estimated to range between 18 and 36 (4–6).Plants contain multiple cesa genes, with 10 found in the Arabidopsis genome (7). Of these, CESA1, CESA3, CESA6, and the CESA6-like CESAs (i.e., CESA2, CESA5, and CESA9) are involved in primary cell wall formation, whereas CESA4, CESA7, and CESA8 participate in secondary cell wall formation (8–12). These two types of CSCs form heterotrimeric complexes with a ratio of 1:1:1 (13, 14). The Arabidopsis CESAs share an overall sequence identity of ∼60% and have seven transmembrane helices (15). In plants, the catalytic domain (CatD) of the CESAs is located between the second and third transmembrane helices and contains a canonical D, D, D, QxxRW motif (1). While there are similarities between the plant CatD and its counterpart in bacterial cellulose synthases, the CatD is flanked by two plant-specific domains, the so-called plant-conserved region (P-CR) and class-specific region (C-SR) (16). These domains are proposed to have important functions in cellulose synthesis and CESA oligomerization (17).The oligomerization of plant CESAs is thought to be important for the final CSC assembly, and multiple oligomeric states of CESAs, including homodimers, have been reported (18, 19). For example, immunoprecipitation assays using CESA7 fused to a dual His/STRP-tag demonstrated that CESA4, CESA7, and CESA8 could form independent homodimers, and it was hypothesized that the CESA homodimerization may contribute to early stages of CSC assembly. These homodimers might then be converted into CSC heterotrimeric configurations (19). This feature poses a marked difference from the bacterial cellulose synthase complex. However, how CESA homodimers are formed and how they function in cellulose synthesis are unknown.To comprehend the mechanisms behind plant cellulose synthesis, it is essential to acquire structural information about plant CESAs. Indeed, the BcsA–BcsB complex structure from Rhodobacter greatly aided our understanding of the cellulose synthesis in bacteria (20). Nevertheless, there are many differences between bacterial and plant CESAs and the corresponding protein complexes. Extensive efforts have been undertaken to acquire plant CESA structural information, including homology modeling and small-angle X-ray scattering analyses (5, 6, 16, 21, 22). While these efforts have been important to form new hypotheses, they did not reveal significant insights into substrate coordination, cellulose chain extrusion, and complex assembly. Recently, a homotrimeric CESA8 structure from Populus tremula × tremuloides was resolved by cryogenic electron microscopy (cryo-EM), which offered significant new molecular understanding of cellulose microfibril biosynthesis and CESA coordination within the CSC (15). Here we report the crystal structures of Arabidopsis CESA3 CatD (AtCESA3CatD) in apo and uridine diphosphate (UDP)-glucose (UDP-Glc) bound forms and outline how the CatD might contribute to CESA homodimerization and substrate coordination. 相似文献
28.
Staffan Bremmer M.D. Sven-Olof Ahlbäck M.D. Rolf Udén M.D. Anders Mellgren M.D. 《Diseases of the colon and rectum》1995,38(9):969-973
A number of physiologic and radiologic investigations are used in investigating defecation disorders. Defecography is one important part of these investigations. However, a correct diagnosis of an enterocele is sometimes difficult despite use of contrast media in the rectum, vagina, and small bowel. PURPOSE: This study was undertaken to ascertain if it was technically possible to perform simultaneous defecography and peritoneography in an effort to improve the diagnostic possibilities in patients with defecation disorders. METHODS: Twelve patients with defecation disorders and an unexplained widening of the rectovaginal space at defecography were investigated. Contrast medium was introduced intraperitoneally, after which conventional defecography was performed. RESULTS: All investigations were carried out without complications and demonstrated the peritoneal outline in all patients. Simultaneous defecography and peritoneography differentiated between an enterocele and a pathologically deep pouch of Douglas—a peritoneocele. Three types of peritoneocele were visualized: vaginal peritoneocele, septal peritoneocele, and rectal peritoneocele with or without enterocele. Combinations of the three types were also found. Eight of the 12 patients had rectal intussusception or rectal prolapse. All of these eight patients had a rectal peritoneocele. CONCLUSIONS: Simultaneous defecography and peritoneography can be performed without technical difficulties or complications. Peritoneal outlines and pouches can, therefore, be studied directly during the act of defecation. An unexplained widening of the rectovaginal space at defecography can be clarified as a peritoneocele, with or without an enterocele. Peritoneocele can be of three different types: rectal, septal, or vaginal.Supported by grants from Marianne and Marcus Wallenbergs Stiftelse, Kjell and Märta Beijers Stiftelse, and Karolinska Institutet's research funds.Poster presentation at the meeting of The American Society of Colon and Rectal Surgeons, Orlando, Florida, May 8 to 13, 1994. 相似文献
29.
Martin O. Weickert Gregory Kaltsas Dieter Hörsch Pablo Lapuerta Marianne Pavel Juan W. Valle Martyn E. Caplin Emily Bergsland Pamela L. Kunz Lowell B. Anthony Enrique Grande Kjell Öberg Staffan Welin Catherine Lombard-Bohas John K. Ramage Ashwin Kittur Qi M. Yang Matthew H. Kulke 《Clinical therapeutics》2018,40(6):952-962.e2
Purpose
In the placebo-controlled Phase III TELESTAR (Telotristat Etiprate for Somatostatin Analogue Not Adequately Controlled Carcinoid Syndrome) trial, the oral tryptophan hydroxylase inhibitor telotristat ethyl significantly reduced bowel movement (BM) frequency during a 12-week, double-blind treatment period in 135 patients with metastatic neuroendocrine tumors with carcinoid syndrome and ≥4 BMs per day. Patients (mean [SD] age, 63.5 [8.9] years; mean [SD] body mass index, 24.9 [4.9] kg/m2) received placebo, telotristat ethyl 250 mg, or telotristat ethyl 500 mg 3 times per day (TID) in addition to somatostatin analogue therapy. Weight loss is associated with uncontrolled carcinoid syndrome and may be associated with reduced survival.Methods
Assessment of the occurrence of weight change ≥3% at week 12 was prespecified in the statistical analysis plan.Findings
In 120 patients with weight data available, weight gain ≥3% was observed in 2 of 39 patients (5.1%) taking placebo TID, 7 of 41 (17.1%) taking telotristat ethyl 250 mg TID, and 13 of 40 (32.5%) taking telotristat ethyl 500 mg TID (P = 0.0017) at week 12. Weight loss ≥3% was observed in 5 of 39 patients (12.8%) taking placebo TID, 4 of 41 (9.8%) taking telotristat ethyl 250 mg TID, and 6 of 40 (15.0%) taking telotristat ethyl 500 mg TID (P = 0.77). Biochemical and metabolic parameters of serum albumin and cholesterol significantly increased (P = 0.02 and P = 0.001, respectively) in patients gaining weight and decreased in patients who lost weight, suggesting an improvement in overall nutritional status.Implications
Up to 32.5% of patients treated with telotristat ethyl experienced significant, dose-dependent weight gain, associated with reduced diarrhea severity and improved biochemical and metabolic parameters. Improved nutritional status could be an additional aspect of telotristat ethyl efficacy among patients with functioning metastatic neuroendocrine tumors. ClinicalTrials.gov identifier: NCT01677910. 相似文献30.
Malin Barman Staffan Nilsson ?sa Torinsson Naluai Anna Sandin Agnes E. Wold Ann-Sofie Sandberg 《Nutrients》2015,7(12):10100-10115
Exposure to polyunsaturated fatty acids (PUFA) influences immune function and may affect the risk of allergy development. Long chain PUFAs are produced from dietary precursors catalyzed by desaturases and elongases encoded by FADS and ELOVL genes. In 211 subjects, we investigated whether polymorphisms in the FADS gene cluster and the ELOVL2 gene were associated with allergy or PUFA composition in serum phospholipids in a Swedish birth-cohort sampled at birth and at 13 years of age; allergy was diagnosed at 13 years of age. Minor allele carriers of rs102275 and rs174448 (FADS gene cluster) had decreased proportions of 20:4 n-6 in cord and adolescent serum and increased proportions of 20:3 n-6 in cord serum as well as a nominally reduced risk of developing atopic eczema, but not respiratory allergy, at 13 years of age. Minor allele carriers of rs17606561 in the ELOVL2 gene had nominally decreased proportions of 20:4 n-6 in cord serum but ELOVL polymorphisms (rs2236212 and rs17606561) were not associated with allergy development. Thus, reduced capacity to desaturase n-6 PUFAs due to FADS polymorphisms was nominally associated with reduced risk for eczema development, which could indicate a pathogenic role for long-chain PUFAs in allergy development. 相似文献