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51.

Aim

Robotic surgery allows for a better visualization and more precise dissection especially in the narrow male pelvis and mid and lower third of the rectum. However, superiority to laparoscopic TME has yet to be proven. We therefore analyzed short-term outcomes of laparoscopic and robotic low anterior rectal resection for rectal cancer.

Patients and methods

From 2011 to 2016, 44 robotic (RTME) and 41 laparoscopic (LTME) low anterior rectal resection with total mesorectal excision were performed at a single institution. Specimen quality was assessed and reported by an independent pathologist following international guidelines.

Results

The groups did not differ significantly regarding gender, age, ASA stage, BMI, and distance of the lower tumor margin from the anal verge. More patients in the RTME group underwent preoperative chemoradiation (43.2 vs. 19.5%, p?=?0.019). The quality of the TME specimen was significantly better in the RTME group (complete/nearly complete/incomplete for RTME 97/0/3% and for LTME 78/17/5%, p?=?0.03). The conversion rate tended to be lower in the RTME group (7 vs. 17%, p?=?0.143). There was no difference in CRM positivity between the groups.

Conclusion

Robotic surgery is safe and can improve the quality of TME for rectal cancer compared to laparoscopy. Any effect on long-term survival remains to be established.
  相似文献   
52.
An altered expression pattern of adhesion molecules (AM) on the surface of immune cells is a premise for their extravasation into the central nervous system (CNS) and the formation of acute brain lesions in multiple sclerosis (MS). We evaluated the impact of glatiramer acetate (GA) on cell‐bound and soluble AM in the peripheral blood of patients with relapsing–remitting MS (RRMS). Fifteen patients treated de novo with GA were studied on four occasions over a period of 12 months. Surface levels of intracellular cell adhesion molecule (ICAM)‐1, ICAM‐3, lymphocyte function‐associated antigen (LFA)‐1 and very late activation antigen (VLA)‐4 were assessed in T cells (CD3+CD8+, CD3+CD4+), B cells, natural killer (NK) cells, natural killer T cells (NK T) and monocytes by five‐colour flow cytometry. Soluble E‐selectin, ICAM‐1, ICAM‐3, platelet endothelial cell adhesion molecule (PECAM)‐1, P‐selectin and vascular cell adhesion molecule (VCAM)‐1 were determined with a fluorescent bead‐based immunoassay. The pro‐migratory pattern in RRMS was verified by comparison with healthy controls and was characterized by up‐regulation of LFA‐1 (CD3+CD4+ T cells, B cells), VLA‐4 (CD3+CD8+ T cells, NK cells), ICAM‐1 (B cells) and ICAM‐3 (NK cells). Effects of GA treatment were most pronounced after 6 months and included attenuated levels of LFA‐1 (CD3+CD4+) and VLA‐4 (CD3+CD4+, CD3+CD8+, NK, NK T, monocytes). Further effects included lowering of ICAM‐1 and ICAM‐3 levels in almost all immune cell subsets. Soluble AM levels in RRMS did not differ from healthy controls and remained unaltered after GA treatment. The deregulated pro‐migratory expression profile of cell‐bound AM is altered by GA treatment. While this alteration may contribute to the beneficial action of the drug, the protracted development and unselective changes indicate more secondary immune regulatory phenomena related to these effects.  相似文献   
53.
Most balanced chromosomal aberrations are not associated with a clinical phenotype, however, in some patients they may disrupt gene structure. With the development of various next-generation sequencing techniques, fast and specific analyses of the breakpoint regions of chromosomal rearrangements are possible. Here, we report on a 19-year-old woman with a de novo balanced translocation t(2;8)(p13.2;q22.1) and a severe clinical phenotype including intellectual disability, epilepsy, behavioral features resembling autism, and minor dysmorphic features. By next-generation sequencing, we defined the breakpoints and found disruption of the exocyst complex component 6B (EXOC6B) gene in intron 1 on chromosome 2p13.2 involving two Alu elements with a homology of 81%. No gene was found at the respective breakpoint on chromosome 8. Expression analysis of the EXOC6B in blood lymphocytes and buccal smear revealed reduced expression in the patient in comparison with the control. Our findings in combination with one recently published case and one other patient listed in DECIPHER v5.1 indicate EXOC6B as a gene relevant for intellectual development and electrophysiological stability.  相似文献   
54.
Ehlers–Danlos syndrome (EDS) leads to abnormalities in the synthesis of collagen and complications involving arterial vessels. We describe here a mutation in the intron 14 of the COL3A1 gene leading to EDS Type IV (EDS IV) associated with venous manifestations only. The patient, an 18-year-old male, suffered from truncal varicosity of the long saphenous vein on both sides. Conventional stripping surgery of the left saphenous vein revealed an extremely vulnerable ectatic superficial femoral vein. An inserted vein graft occluded, and venous thrombectomy was unsuccessful. A conservative anticoagulant and compression therapy finally succeeded. This is the first report describing EDS IV due to a mutation in intron 14 of the COL3A1 gene leading to venous manifestations without affecting arterial vessels at clinical presentation. Our findings imply that molecular genetic analysis should be considered in patients with unusual clinical presentation and that conservative therapy should be applied until a suspected clinical diagnosis has been secured.  相似文献   
55.
BackgroundAn infraacetabular screw path facilitates the closure of a periacetabular fixation frame to increase the plate fixation strength in acetabular fractures up to 50%. Knowledge of the variance in corridor sizes and axes has substantial surgical relevance for safe screw placement.Questions/purposes(1) What proportion of healthy pelvis specimens have an infraacetabular corridor that is 5 mm or larger in diameter? (2) Does a universal corridor axis and specific screw entry point exist? (3) Are there sex-specific differences in the infraacetabular corridor size or axis and are these correlated with anthropometric parameters like age, body weight and height, or the acetabular diameter?MethodsA template pelvis with a mean shape from 523 segmented pelvis specimens was generated using a CT-based advanced image analyzing system. Each individual pelvis was registered to the template using a free-form registration algorithm. Feasible surface regions for the entry and exit points of the infraacetabular corridor were marked on the template and automatically mapped to the individual samples to perform a measurement of the maximum sizes and axes of the infraacetabular corridor on each specimen. A minimum corridor diameter of at least 5 mm was defined as a cutoff for placing a 3.5-mm cortical screw in clinical settings.ResultsIn 484 of 523 pelves (93%), an infraacetabular corridor with a diameter of at least 5 mm was found. Using the mean axis angulations (54.8° [95% confidence interval {CI}, 0.6] from anterocranial to posterocaudal in relation to the anterior pelvic plane and 1.5° [95% CI, 0.4] from anteromedial to posterolateral in relation to the sagittal midline plane), a sufficient osseous corridor was present in 64% of pelves. Allowing adjustment of the three-dimensional axis by another 5° included an additional 25% of pelves. All corridor parameters were different between females and males (corridor diameter, 6.9 [95% CI, 0.2] versus 7.7 [95% CI, 0.2] mm; p < 0.001; corridor length, 96.2 [95% CI, 0.7] versus 106.4 [95% CI, 0.6] mm; p < 0.001; anterior pelvic plane angle, 54.0° [95% CI, 0.9] versus 55.3° [95% CI, 0.8]; p < 0.01; sagittal midline plane angle, 4.3° [95% CI, 0.6] versus −0.3° [95% CI, 0.5]; p < 0.001).ConclusionThis study provided reference values for placement of a 3.5-mm cortical screw in the infraacetabular osseous corridor in 90% of female and 94% of male pelves. Based on the sex-related differences in corridor axes, the mean screw trajectory is approximately parallel to the sagittal midline plane in males but has to be tilted from medial to lateral in females. Considering the narrow corridor diameters, we suggest an individual preoperative CT scan analysis for fine adjustments in each patient.  相似文献   
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BACKGROUND: We have observed profound deficits in hippocampal synaptic plasticity and one-trial learning in offspring whose mothers drank moderate quantities of ethanol during pregnancy. In the present study, we examined the question of whether lower maternal blood ethanol concentrations (BECs) could produce functional deficits in offspring. METHODS: Rat dams consumed either a 2%, 3%, or 5% ethanol liquid diet throughout gestation. Three other groups of dams were pair-fed a 0% ethanol liquid diet, and a seventh group consumed lab chow ad libitum. Adult offspring from each diet group were assigned either to studies of evoked [3H]-D-aspartate (D-ASP) release from hippocampal slices or spatial learning studies using the Morris Water Task. RESULTS: Consumption of the 2%, 3%, and 5% ethanol liquid diets produced mean peak maternal BECs of 7, 30 and 83 mg/dL, respectively. Consumption of these ethanol diets had no effect on offspring birthweight, litter size or neonatal mortality. Likewise, evoked D-ASP release from hippocampal slices and performance on a standard version of the Morris Water Task were not affected by prenatal ethanol exposure. By contrast, activity-dependent potentiation of evoked D-ASP release from slices and one-trial learning on a "moving platform" version of the Morris Water Task were markedly reduced in offspring whose mothers consumed the 5% ethanol liquid diet. Intermediate deficits in these two parameters were observed in offspring from the 3% ethanol diet group, whereas offspring from the 2% ethanol diet group were not statistically different than controls. CONCLUSIONS: We conclude that the threshold for eliciting subtle, yet significant learning deficits in offspring prenatally exposed to ethanol is less than 30 mg/dL. This BEC is roughly equivalent to drinking 1 to 1.5 ounces of ethanol per day.  相似文献   
60.
Inositol-1,4,5-triphosphate (IP3) kinase B (ITPKB) is a ubiquitously expressed lipid kinase that inactivates IP3, a secondary messenger that stimulates calcium release from the endoplasmic reticulum (ER). Genome-wide association studies have identified common variants in the ITPKB gene locus associated with reduced risk of sporadic Parkinson’s disease (PD). Here, we investigate whether ITPKB activity or expression level impacts PD phenotypes in cellular and animal models. In primary neurons, knockdown or pharmacological inhibition of ITPKB increased levels of phosphorylated, insoluble α-synuclein pathology following treatment with α-synuclein preformed fibrils (PFFs). Conversely, ITPKB overexpression reduced PFF-induced α-synuclein aggregation. We also demonstrate that ITPKB inhibition or knockdown increases intracellular calcium levels in neurons, leading to an accumulation of calcium in mitochondria that increases respiration and inhibits the initiation of autophagy, suggesting that ITPKB regulates α-synuclein pathology by inhibiting ER-to-mitochondria calcium transport. Furthermore, the effects of ITPKB on mitochondrial calcium and respiration were prevented by pretreatment with pharmacological inhibitors of the mitochondrial calcium uniporter complex, which was also sufficient to reduce α-synuclein pathology in PFF-treated neurons. Taken together, these results identify ITPKB as a negative regulator of α-synuclein aggregation and highlight modulation of ER-to-mitochondria calcium flux as a therapeutic strategy for the treatment of sporadic PD.

Parkinson’s disease (PD) is a progressive neurodegenerative disorder characterized by a variety of motor symptoms (including unbalanced gait, resting tremor, and bradykinesia) that are accompanied by psychosis and dementia at later stages of disease. The onset of motor symptoms is largely caused by the selective loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc) and the corresponding depletion of dopamine innervation in the striatum. Although the cause of neuron loss is unknown, the hallmark pathological feature of PD is the presence of intraneuronal inclusions composed of misfolded and fibrillar α-synuclein (α-syn) in the neurites and soma, termed Lewy neurites and Lewy bodies, respectively (1). Protein-coding single-nucleotide polymorphisms (SNPs), duplications, and triplications in the gene encoding α-syn (SNCA) all cause early-onset, familial forms of PD and result in accelerated aggregation of α-syn protein into insoluble, fibrillar aggregates (1, 2). Recent evidence suggests that these aggregates can spread from cell to cell, leading to the propagation of pathology to neuroanatomically connected brain regions (3, 4). Therefore, therapeutic approaches that reduce the aggregation or spreading of pathological α-syn species represent potential disease-modifying therapies for PD.In addition to SNCA, mutations in several other genes have been identified that cause rare, familial forms of PD. These genes are primarily involved in the autophagic clearance of intracellular aggregates or damaged organelles, especially mitochondria (58). Genome-wide association studies (GWAS) have also identified common SNPs in several genes related to endolysosomal function, such as GBA and LRRK2, that are associated with increased risk of PD (811). GBA and LRRK2 mutations have been shown to affect lysosomal and mitochondrial phenotypes (1214), which contribute to the accumulation of PD-like neuropathology in mouse models, primary neurons, and human iPSC-derived cells (1518). These findings highlight the role of the lysosomal and mitochondria quality control pathways in PD and demonstrate that perturbations in these pathways are sufficient to increase α-syn aggregation. Despite this, the etiology of sporadic PD is not fully understood, and the specific genes and pathways that are tractable for therapeutic modulation remain elusive. Therefore, the discovery of new genes associated with sporadic PD may be critical for both understanding disease pathogenesis and identifying novel therapeutic approaches.Recently, Chang et al. conducted a GWAS analysis that identified 17 novel gene loci significantly associated with sporadic PD in a European population including more than 26,000 patients across three independent cohorts (19). The lead GWAS SNP in the novel 1q42 locus was rs4653767. This is an intronic SNP in the gene encoding inositol-1,4,5-triphosphate kinase B (ITPKB) and produces a thymine-to-cytosine nucleotide substitution that is protective against developing PD (odds ratio [OR] = 0.92, P = 2.4 × 10−10). A follow up meta-analysis study of 37,688 PD patients, which included the discovery cohort, and 18,618 proxy cases strengthened the GWAS finding at this locus (OR = 0.92, P = 1.4 × 10−15). Furthermore, this locus was still significant when the analysis was performed on only the new independent cases and proxy cases (OR = 0.92, P = 2.8 × 10−5) (20). The rs4653767-C allele is present in similar frequencies across populations (27% in non-Finnish European and 29% in East Asian populations) and was found to have the same direction of effect (OR = 0.87, P = 0.016) in a targeted replication study of the European PD loci in an East Asian cohort (21). ITPKB is also highly expressed in several brain regions related to PD, including the SNpc, striatum, and cerebral cortex (22).ITPKB is one of three ubiquitously expressed kinases known to phosphorylate inositol-1,4,5-triphosphate (IP3), an intracellular messenger produced from phosphatidylinositol-4,5-bisphosphate by phospholipase C (23, 24). IP3 binds to IP3 receptors (IP3Rs) in the endoplasmic reticulum (ER) to stimulate the release of calcium ions from the ER into the cytosol to mediate various downstream signaling pathways. IP3 kinases (ITPKA, ITPKB, and ITPKC) add a fourth phosphate group to IP3 producing inositol-1,3,4,5-tetrakisphosphate (IP4), which has no activity on IP3Rs. Thus, IP3 kinases negatively regulate IP3-mediated calcium release from the ER. While the role of this pathway in peripheral cell types under normal physiological conditions is well understood (25, 26), whether ITPKB is involved in the pathogenesis of PD is unknown. Here, we investigate whether the modulation of ITPKB expression or kinase activity impacts the accumulation of α-syn pathology in cellular models of PD.  相似文献   
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