966 resultados para Dislocation Patterning
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While bank investment is a driving force behind neighborhood viability, few studies have directly examined the effects of bank loan practices on neighborhood crime rates. This paper proposes that residential bank loan policies help explain the higher rates of homicide in minority neighborhoods in Chicago compared to white neighborhoods. It finds that black and Latino neighborhoods would experience fewer homicides if more financial capital were infused into these neighborhoods. These findings suggest that neighborhoods are shaped profoundly by the decisions of external economic actors.
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Muscarinic receptors mediate acetylcholine-induced muscular contractions. In this study, mRNA levels of muscarinic receptor subtypes 2 and 3 (M(2) and M(3)) in the ileum, caecum, proximal loop of the ascending colon (PLAC) and external loop of the spiral colon (ELSC) were determined by quantitative polymerase chain reaction in seven cows with caecal dilatation-dislocation (CDD) and seven healthy control cows. Levels of M(2) were significantly lower in the caecum, PLAC and ELSC and levels of M(3) were significantly lower in the ileum, caecum, PLAC and ELSC of cows with CDD compared to healthy cows (P<0.05). Down-regulation of M(3) may play a role in the pathogenesis of CDD.
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BACKGROUND Traumatic posterior hip dislocation in adults is generally understood to be the result of a high-energy trauma. Aside from reduced femoral antetorsion, morphologic risk factors for dislocation are unknown. We previously noticed that some hips with traumatic posterior dislocations had evidence of morphologic features of femoroacetabular impingement (FAI), therefore, we sought to evaluate that possibility more formally. QUESTIONS/PURPOSES We asked whether hips with a traumatic posterior hip dislocation present with (1) a cam-type deformity and/or (2) a retroverted acetabulum. METHODS We retrospectively compared the morphologic features of 53 consecutive hips (53 patients) after traumatic posterior hip dislocation with 85 normal hips (44 patients) based on AP pelvic and crosstable axial radiographs. We measured the axial and the lateral alpha angle for detection of a cam deformity and the crossover sign, ischial spine sign, posterior wall sign, retroversion index, and ratio of anterior to posterior acetabular coverage to describe the acetabular orientation. RESULTS Hips with traumatic posterior traumatic dislocation were more likely to have cam deformities than were normal hips, in that the hips with dislocation had increased axial and lateral alpha angles. Hips with posterior dislocation also were more likely to be retroverted; dislocated hips had a higher prevalence of a positive crossover sign, ischial spine sign, and posterior wall sign, and they had a higher retroversion index and increased ratio of anterior to posterior acetabular coverage. CONCLUSIONS Hips with posterior traumatic dislocation typically present with morphologic features of anterior FAI, including a cam-type deformity and retroverted acetabulum. An explanation for these findings could be that the early interaction between the aspherical femoral head and the prominent acetabular rim acts as a fulcrum, perhaps making these hips more susceptible to traumatic dislocation.
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Agrobacterium VirB2 pilin is required for assembly of the VirB/VirD4 type IV secretion system (T4SS). The propilin is processed by signal sequence cleavage and covalent linkage of the N and C termini, and the cyclized pilin integrates into the inner membrane (IM) as a pool for assembly of the secretion channel and T pilus. Here, by use of the substituted cysteine accessibility method (SCAM), we defined the VirB2 IM topology and then identified distinct contributions of the T4SS ATPase subunits to the pilin structural organization. Labeling patterns of Cys-substituted pilins exposed to the membrane-impermeative, thiol-reactive reagent 3-(N-maleimidopropionyl)biocytin (MPB) supported a topology model in which two hydrophobic stretches comprise transmembrane domains, an intervening hydrophilic loop (residues 90 to 94) is cytoplasmic, and the hydrophilic N and C termini joined at residues 48 and 121 form a periplasmic loop. Interestingly, the VirB4 ATPase, but not a Walker A nucleoside triphosphate (NTP) binding motif mutant, induced (i) MPB labeling of Cys94, a residue that in the absence of the ATPase is located in the cytoplasmic loop, and (ii) release of pilin from the IM upon osmotic shock. These findings, coupled with evidence for VirB2-VirB4 complex formation by coimmunoprecipitation, support a model in which VirB4 functions as a dislocation motor to extract pilins from the IM during T4SS biogenesis. The VirB11 ATPase functioned together with VirB4 to induce a structural change in the pilin that was detectable by MPB labeling, suggestive of a role for VirB11 as a modulator of VirB4 dislocase activity.
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Leaves are arranged according to regular patterns, a phenomenon referred to as phyllotaxis. Important determinants of phyllotaxis are the divergence angle between successive leaves, and the size of the leaves relative to the shoot axis. Young leaf primordia are thought to provide positional information to the meristem, thereby influencing the positioning of new primordia and hence the divergence angle. On the contrary, the meristem signals to the primordia to establish their dorsoventral polarity, which is a prerequisite for the formation of a leaf blade. These concepts originate from classical microsurgical studies carried out between the 1920s and the 1970s. Even though these techniques have been abandoned in favor of genetic analysis, the resulting insights remain a cornerstone of plant developmental biology. Here, we employ new microsurgical techniques to reassess and extend the classical studies on phyllotaxis and leaf polarity. Previous experiments have indicated that the isolation of an incipient primordium by a tangential incision caused a change of divergence angle between the two subsequent primordia, indicating that pre-existing primordia influence further phyllotaxis. Here.. we repeat these experiments and compare them with the results of laser ablation of incipient primordia. Furthermore. we explore to what extent the different pre-existing primordia influence the size and position of new organs. and hence phyllotaxis. We propose that the two youngest primordia (P-1 and P-2) are sufficient for the approximate positioning of the incipient primordium (I-1), and therefore for the perpetuation of the generative spiral, whereas the direct contact neighbours of I-1 (P-2 and P-3) control its delimitation and hence its exact size and position. Finally. we report L I specific cell ablation experiments suggesting that the meristem L-1 layer is essential for the dorsoventral patterning of leaf primordia.
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BACKGROUND Patients with femoroacetabular impingement (FAI) often develop pain, impaired function, and progression of osteoarthritis (OA); this is commonly treated using surgical hip dislocation, femoral neck and acetabular rim osteoplasty, and labral reattachment. However, results with these approaches, in particular risk factors for OA progression and conversion to THA, have varied. QUESTIONS/PURPOSES We asked if patients undergoing surgical hip dislocation with labral reattachment to treat FAI experienced (1) improved hip pain and function; and (2) prevention of OA progression; we then determined (3) the survival of the hip at 5-year followup with the end points defined as the need for conversion to THA, progression of OA by at least one Tönnis grade, and/or a Merle d'Aubigné-Postel score less than 15; and calculated (4) factors predicting these end points. METHODS Between July 2001 and March 2003, we performed 146 of these procedures in 121 patients. After excluding 35 patients (37 hips) who had prior open surgery and 11 patients (12 hips) who had a diagnosis of Perthes disease, this study evaluated the 75 patients (97 hips, 66% of the procedures we performed during that time) who had a mean followup of 6 years (range, 5-7 years). We used the anterior impingement test to assess pain, the Merle d'Aubigné-Postel score to assess function, and the Tönnis grade to assess OA. Survival and predictive factors were calculated using the method of Kaplan and Meier and Cox regression, respectively. RESULTS The proportion of patients with anterior impingement decreased from 95% to 17% (p < 0.001); the Merle d'Aubigné-Postel score improved from a mean of 15 to 17 (p < 0.001). Seven hips (7%) showed progression of OA and another seven hips (7%) converted to THA Survival free from any end point (THA, progression of OA, or a Merle d'Aubigné-Postel < 15) of well-functioning joints at 5 years was 91%; and excessive acetabular rim trimming, preoperative OA, increased age at operation, and weight were predictive factors for the end points. CONCLUSIONS At 5-year followup, 91% of patients with FAI treated with surgical hip dislocation, osteoplasty, and labral reattachment showed no THA, progression of OA, or an insufficient clinical result, but excessive acetabular trimming, OA, increased age, and weight were associated with early failure. To prevent early deterioration of the joint, excessive rim trimming or trimming of borderline dysplastic hips has to be avoided.
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OBJECTIVE To analyze the transit time from various locations in the intestines of cows with cecal dilatation-dislocation (CDD), healthy control cows, and cows with left displacement of the abomasum (LDA). ANIMALS 15 cows with naturally occurring CDD (group 1), 14 healthy control cows (group 2), and 18 cows with LDA (group 3). PROCEDURES 5 electronic transmitters were encased in capsules and placed in the lumen of the ileum, cecum, proximal portion of the colon, and 2 locations in the spiral colon (colon 1 and colon 2) and used to measure the transit time (ie, time between placement in the lumen and excretion of the capsules from the rectum). Excretion time of the capsules from each intestinal segment was compared among groups. RESULTS Cows recovered well from surgery, except for 1 cow with relapse of CDD 4 days after surgery and 2 cows with incisional infection. High variability in capsule excretion times was observed for all examined intestinal segments in all groups. Significant differences were detected for the excretion time from the colon (greater in cows with CDD than in healthy control cows) and cecum (less in cows with LDA than in cows of the other 2 groups). CONCLUSIONS AND CLINICAL RELEVANCE The technique developed to measure excretion time of capsules from bovine intestines was safe and reliable; however, the large variability observed for all intestinal segments and all groups would appear to be a limitation for its use in assessment of intestinal transit time of cattle in future studies.
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BACKGROUND Traumatic knee dislocation represents a rare but devastating injury. Several controversies persist regarding type of treatment, surgical timing, graft selection, repair versus reconstruction of the medial and lateral structures, surgical techniques and postoperative rehabilitation. A new technique for primary ACL stabilization, dynamic intaligamentary stabilization (DIS) was developed at the authors' institution. The purpose of this study was to analyze the clinical and radiological outcomes of surgically treated traumatic knee dislocations by means of the DIS technique for the ACL, primary suturing for PCL, MCL and LCL. METHODS Between 2009 and 2012, 35 patients treated surgically for traumatic knee dislocation with primary anterior cruciate ligament (ACL) reconstruction with DIS, suturing of the posterior cruciate ligament (PCL) and primary complete repair of collaterals, were evaluated clinically (IKDC score, SF12 health survey, Lysholm score, Tegner score) and radiologically with a mean follow up of 2.2 years (range 1.00-3.50 years) years. Instrumented anterior-posterior translation was measured (KT-2000). RESULTS Anterior/posterior translation (KT-2000) for the healthy and injured limb was 4.8mm (range 3-8mm) and 7.3mm (range 5-10) (89N) respectively. Valgus and varus stress testing in 30° flexion was normal in 26 (75%) and 29 (83%) patients, respectively. The IKDC score was B in 29 (83%) and C in 6 (17%) patients, while the mean Tegner score was 6 (range 4-8). The mean Lysholm score was 90.83 (range 81-95) and mean SF-12 physical and mental scores were 54.1 (range 45-60) and 51.0 (range 39-62) respectively. In 2 patients, a secondary operation was performed. CONCLUSIONS Early, one stage reconstruction with DIS can achieve good functional results and patient satisfaction with overall restoration of sports and working capacity without graft requirements.
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Several componential emotion theories suggest that appraisal outcomes trigger characteristic somatovisceral changes that facilitate information processing and prepare the organism for adaptive behavior. The current study tested predictions derived from Scherer's Component Process Model. Participants viewed unpleasant and pleasant pictures (intrinsic pleasantness appraisal) and were asked to concurrently perform either an arm extension or an arm flexion, leading to an increase or a decrease in picture size. Increasing pleasant stimuli and decreasing unpleasant stimuli were considered goal conducive; decreasing pleasant stimuli and increasing unpleasant stimuli were considered goal obstructive (goal conduciveness appraisal). Both appraisals were marked by several somatovisceral changes (facial electromyogram, heart rate (HR)). As predicted, the changes induced by the two appraisals showed similar patterns. Furthermore, HR results, compared with data of earlier studies, suggest that the adaptive consequences of both appraisals may be mediated by stimulus proximity.