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121.
Objectives: We sought to determine the effects of experience on the Mitraclip® procedure steps as well as procedure safety and functional results. Background: MR has proven deleterious in heart failure. Mitraclip® therapy evolved an important option in patients with severely reduced left ventricular function (LVEF). Methods: Between 2011 and 2016, 126 consecutive patients were grouped in three groups and investigated in a prospective observational study. We evaluated the duration of procedural steps, safety endpoints, and functional results. Results: The median logistic EuroScore was 32% (7–40%). Ninety‐five percent of patients were in NYHA‐stage ≥III and 51% had a LVEF <30%. Groups were homogeneous as to their baseline NYHA status and right heart catheterization data. Echocardiography data are comparable, albeit with a decreasing effective regurgitant orifice area (0.44 ± 0.21 group I vs. 0.34 ± 0.22 group III, P = 0.02). Frailty was less frequent and baseline 6 min walking test results improved from group I to group III. Duration of a first clip placement decreased from 106 ± 50 to 50 ± 21 min (P < 0.001). Total procedure time decreased from 221 ± 70 to 144 ± 68 (P < 0.001). The number of clips implanted increased from 66 to 79 (P = 0.02). MitraClip® implantation was effective in either group but the combined safety endpoint was reached less frequent in group III (P = 0.01). There was no difference in MACCE rate, 30 day‐ or intrahospital‐mortality between groups. Conclusion: Safety and duration of procedure steps improved substantially with experience. MR reduction was sustained from the beginning without further improvement. Patient selection is a key factor for success. © 2016 Wiley Periodicals, Inc.  相似文献   
122.
Neurons secrete neuropeptides from dense core vesicles (DCVs) to modulate neuronal activity. Little is known about how neurons manage to differentially regulate the release of synaptic vesicles (SVs) and DCVs. To analyze this, we screened all Caenorhabditis elegans Rab GTPases and Tre2/Bub2/Cdc16 (TBC) domain containing GTPase-activating proteins (GAPs) for defects in DCV release from C. elegans motoneurons. rab-5 and rab-10 mutants show severe defects in DCV secretion, whereas SV exocytosis is unaffected. We identified TBC-2 and TBC-4 as putative GAPs for RAB-5 and RAB-10, respectively. Multiple Rabs and RabGAPs are typically organized in cascades that confer directionality to membrane-trafficking processes. We show here that the formation of release-competent DCVs requires a reciprocal exclusion cascade coupling RAB-5 and RAB-10, in which each of the two Rabs recruits the other’s GAP molecule. This contributes to a separation of RAB-5 and RAB-10 domains at the Golgi–endosomal interface, which is lost when either of the two GAPs is inactivated. Taken together, our data suggest that RAB-5 and RAB-10 cooperate to locally exclude each other at an essential stage during DCV sorting.  相似文献   
123.
We measured chronic electrocorticography (ECoG) of sensorimotor cortex during contralateral median nerve stimulation in 6 patients with partial seizures evaluated for surgery. We analyzed the spatiotemporal structure of the somatosensory evoked response (SER) using multiple source modeling to investigate functional anatomy of its neuronal sources. Two dipole sources in postcentral gyrus explained the large majority of the first 60 msec of the SER, indicating a subregion of hand somatosensory cortex generating this activity. The source locations agreed with normal functional anatomy from cortical stimulations, intraoperative photographs, and postoperative neurological examinations after focal excisions. The time patterns of both sources were biphasic like the previously described N20-P30 and P25-N35 peaks. The spatiotemporal patterns of both sources overlapped. Spatiotemporal analysis with multiple dipole sources appears useful to determine the number, locations, and spatiotemporal field patterns of cortical regions active during peripheral somatosensory stimulation and reveals simplicity in the macroscopic functional anatomy of dynamic human sensorimotor cortex.  相似文献   
124.

Background Context

Prior reports have compared posterior column osteotomies with pedicle subtraction osteotomies in terms of utility for correcting fixed sagittal imbalance in adolescent patients with deformity. No prior reports have described the use of multilevel Smith-Petersen Osteotomies (SPOs) alone for surgical correction in the adult spinal deformity (ASD) population.

Purpose

The study aimed to determine the utility of multilevel SPOs in the management of global sagittal imbalance in ASD patients.

Study Design/Setting

This is a retrospective observational study at a single academic center.

Patient Sample

The sample included 85 ASD patients.

Outcome Measures

This is a radiographic outcomes cohort study.

Methods

The radiographs of 85 ASD patients were retrospectively evaluated before and after long-segment (>5 spinal levels) fusion and multilevel SPO (≥3 levels) for sagittal imbalance correction. The number of osteotomies, correction in regional lumbar lordosis (LL), and correction per osteotomy was evaluated. Independent predictors of correction per SPO were evaluated with a hierarchical linear regression analysis.

Results

Eighty-five patients (mean age: 67.5±11 years) were identified with ASD (372 SPOs). The mean preoperative sagittal vertical axis (SVA) and T1 pelvic angle (TPA) were 8.16±6.75?cm and 25°±13.23°, respectively. The mean postoperative central sacral vertical line (CSVL) and SVA were 0.67±0.70?cm and 1.29±5.41?cm, respectively. The mean improvement in SVA was 6.29?cm achieved with a correction of approximately 5.05° per SPO. The mean LL restoration was 20.3°±13.9°, and 33(39%) patients achieved a final pelvic incidence minus lumbar lordosis (PI-LL) ≤10°. Fifty-four (64%) achieved a postoperative PI-LL ≤15°, 75 (88%) with a PI-LL ≤20°, and 85 (100%) achieved a PI-LL ≤25°. Correction per SPO was similar regardless of prior fusion (4.87° vs. 5.72° for revisions, p=.192). In a subgroup analysis of SVA greater than 10?cm, there was no significant difference in the final LL, thoracic kyphosis, PI-LL, SVA, CSVL, and TPA, as compared with SVA <10?cm. The LL was the only independent predictor of osteotomy correction per level (LL: β coefficient=?0.108, confidence interval: ?0.141 to 0.071, p<.0001).

Conclusions

Multilevel SPOs are feasible for restoration of LL as well as sagittal and coronal alignment in the ASD population with or without prior instrumented fusion.  相似文献   
125.
OBJECTIVE: To investigate skeletal growth and bone metabolism in a chronic animal model of urinary diversion. MATERIALS AND METHODS: Young male Wistar rats (120) were allocated randomly to four groups undergoing: ileocystoplasty, ileocystoplasty and resection of the ileocaecal segment, colocystoplasty, and controls. All animals received antibiotics for 1 week after surgery; half of each group remained on oral antibiotics. Bone-related biochemistry was measured in serum and urine. Dual-energy X-ray absorptiometry and peripheral quantitative computed tomography (pQCT) were used to determine bone mass ex vivo. RESULTS: Most (90%) of the rats survived the study period (8 months); six rats died from bowel obstruction at the level of the entero-anastomosis and four had to be killed because of persistent severe diarrhoea. Vital intestinal mucosa was found in all augmented bladders. There were no differences in bone length and volume. Loss of bone mass was almost exclusively in rats with ileocystoplasty and resection of the ileocaecal segment (-37.5%, pQCT, P < 0.01). There was no hyperchloraemic metabolic acidosis or gross impairment of renal function. Hypomagnesaemia, hypocalcaemia and decreased insulin-like growth factor-binding protein 3 were the only significant findings on blood analysis. Deoxypyridinoline crosslinks in urine were higher in rats with an enterocystoplasty than in controls. CONCLUSIONS: Enterocystoplasty in rats neither impairs skeletal growth nor bone quantity, but leads to significant loss of bone mass when combined with resection of the ileocaecal segment. Rarefaction of the trabecular network is confined to the metabolically highly active cancellous compartment, most likely as a consequence of intestinal malabsorption.  相似文献   
126.
The subtilase cytotoxin (SubAB) belongs to the family of AB5 toxins and is produced together with Shiga toxin (Stx) by certain Stx-producing E. coli strains (STEC). For most AB-type toxins, it is assumed that cytotoxic effects can only be induced by a complete holotoxin complex consisting of SubA and SubB. However, it has been shown for SubAB that the enzymatically active subunit SubA, without its transport and binding domain SubB, induces cell death in different eukaryotic cell lines. Interestingly, the molecular structure of SubA resembles that of the SubAB complex. SubA alone is capable of binding to cells and then being taken up autonomously. Once inside the host cell, SubA is transported, similar to the SubAB holotoxin, via a retrograde transport into the endoplasmatic reticulum (ER). In the ER, it exhibits its enzymatic activity by cleaving the chaperone BiP/GRP78 and thereby triggering cell death. Therefore, the existence of toxic single SubA subunits that have not found a B-pentamer for holotoxin assembly might improve the pathogenic potential of subtilase-producing strains. Moreover, from a pharmacological aspect, SubA might be an interesting molecule for the targeted transport of therapeutic molecules into the ER, in order to investigate and specifically modulate processes in the context of ER stress-associated diseases. Since recent studies on bacterial AB5 toxins contributed mainly to the understanding of the biology of AB-type holotoxins, this mini-review specifically focus on that recently observed single A-effect of the subtilase cytotoxin and addresses whether a fundamental shift of the traditional AB5 paradigm might be required.  相似文献   
127.
Computed tomography is currently the standard in preoperative evaluation of facial fractures, but cone beam computed tomography (CBCT) or digital volume tomography (DVT) offers potential advantages. Intraoperative imaging may facilitate adequate fracture reduction, optimising fracture repair. The aim of this article is to demonstrate the potential benefits of a new mobile CBCT system in a series of patients with complex facial fractures. Intraoperative imaging was performed with the xCAT ENT portable CBCT system. Images were provided in three planes and in a three-dimensional reconstruction. This system was used for intraoperative imaging of 46 consecutive facial trauma patients. The impact of intraoperative CBCT on the management of these cases is described and two select cases are presented to illustrate the potential benefits of this technique. Intraoperative CBCT was successfully performed in all patients and has led to immediate consequences in 12 (26%) cases. In 5 cases, fracture reduction turned out to be insufficient and was further optimized and in 5 other cases the titanium implan (orbital mesh) was not placed in the optimal position and the position was corrected. Bony fragments were detected and removed in 2 cases. Intraoperative imaging provides a number of advantages over post-therapeutic imaging in the management of facial fractures.  相似文献   
128.
We report 26 human isolates of mcr-1–positive Escherichia coli, most of them (65.4%) with a polymyxin B MIC of 2?mg/L. Seventeen out of the 24 mcr-1–positive E. coli proved to be nonclonal by rep-PCR which strengthens the hypothesis of environmental or animal origin of these strains and reinforces the one health context of antimicrobial resistance.  相似文献   
129.
We identified one clinical isolate of K. pneumoniae harboring the mcr 1 (plasmid of IncX4 family) and blaKPC-2 (plasmid of IncFIB family) genes in southern Brazil. These findings highlight that K. pneumoniae isolates carrying both mcr-1 and blaKPC-2 may emergence as a serious threat to antimicrobial therapy.  相似文献   
130.
Tick-borne encephalitis virus (TBEV) diagnosis is mainly based on the detection of viral-specific antibodies in serum. Several commercial assays are available, but published data on their performance remain unclear. We assessed six IgM and six IgG commercial enzyme-linked immunosorbent assay (ELISA) kits (ELISA-1 through ELISA-6) using 94 samples, including precharacterized TBEV-positive samples (n=50) and -negative samples (n=44). The six manufacturers showed satisfactory sensitivity and specificity and high overall agreement for both IgM and IgG. Three manufacturers showed better reproducibility and were the most sensitive (100%) and specific (95.5–98.1%) for both IgM and IgG. Two of them were also in agreement with the clinical interpretation in more than 90% of the cases. All the assays use inactivated virus as antigen, with strains showing approximately 94% homology at the amino acid level. The antigenic format of the assays was discussed to further improve this TBEV diagnostic tool.  相似文献   
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