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71.
72.
Injury to the spinal cord not only disrupts the functioning of spinal circuits at the site of the impact, but also limits sensorimotor function caudal to the level of the lesion. Ratings of gross locomotor skill are generally used to quantify locomotor recovery following spinal cord injury (SCI). The purpose of this study was to assess behavioral recovery following SCI with three tasks: (1) BBB ratings, (2) walking on a horizontal ladder, and (3) footprint analyses. Behavioral testing was conducted for 6 postoperative weeks, and then the spinal cords were processed for the amount of white matter spared. As expected, BBB ratings dramatically decreased and then improved during recovery. The number of hindlimb foot-faults on the horizontal ladder increased after injury and remained elevated during the recovery period. Footprint analyses revealed that sham-control rats used several different gaits to cross the runway. In contrast, the locomotor function of rats with a SCI was impaired throughout the postoperative period. Some locomotor parameters of the injured rats improved slightly (velocity, stride length, stride duration, stance duration), some did not change (interlimb coordination, swing duration, forelimb base of support, hindpaw angle), and others declined (hindlimb base of support) during the recovery period. Together, these results show that gross locomotor skill improved after SCI, while recovery of fine locomotor function was more limited. Multiple tests should be included in future experiments in order to assess gross and fine changes in sensorimotor function following SCI.  相似文献   
73.

Background

Epithelial sodium channel (ENaC, Scnn1) hyperactivity in the lung leads to airway surface dehydration and mucus accumulation in cystic fibrosis (CF) patients and in mice with CF-like lung disease.

Methods

We identified several potent ENaC specific antisense oligonucleotides (ASOs) and tested them by inhalation in mouse models of CF-like lung disease.

Results

The inhaled ASOs distributed into lung airway epithelial cells and decreased ENaC expression by inducing RNase H1-dependent degradation of the targeted Scnn1a mRNA. Aerosol delivered ENaC ASO down-regulated mucus marker expression and ameliorated goblet cell metaplasia, inflammation, and airway hyper-responsiveness. Lack of systemic activity of ASOs delivered via the aerosol route ensures the safety of this approach.

Conclusions

Our results demonstrate that antisense inhibition of ENaC in airway epithelial cells could be an effective and safe approach for the prevention and reversal of lung symptoms in CF and potentially other inflammatory diseases of the lung.  相似文献   
74.
Purpose

Little is known about the perioperative characteristics associated with a posterior spinal fusion (PSF) in adolescent idiopathic scoliosis patients previously treated with vertebral body tethering (VBT). We aimed to determine if operative time, estimated blood loss, postoperative length of stay, instrumentation type, and implant density differed in patients that received a PSF (i.e., PSF-Only) or a PSF following a failed VBT (i.e., PSF–VBT).

Methods

We retrospectively assessed matched cohort data (PSF–VBT = 22; PSF-Only = 22) from two multi-center registries. We obtained: (1) operative time, (2) estimated blood loss, (3) postoperative length of stay, (4) instrumentation type, and (5) implant density. Theoretical fusion levels prior to the index procedure were obtained for PSF–VBT and compared to the actual levels fused.

Results

We observed no difference in operative time, estimated blood loss, or postoperative length of stay. Instrumentation type was all-screw in PSF-Only and varied in PSF–VBT with nearly 25% of patients exhibiting a hybrid construct. There was no added benefit to removing anterior instrumentation prior to fusion; however, implant density was higher in PSF-Only (1.9 ± 0.2) than when compared to PSF–VBT (1.7 ± 0.3). An additional two levels were fused in 50% of PSF–VBT patients, most of which were added to the distal end of the construct.

Conclusions

We found that operative time, estimated blood loss, and postoperative length of stay were similar in both cohorts; however, the length of the fusion construct in PSF–VBT is likely to be two levels longer when a failed VBT is converted to a PSF.

  相似文献   
75.
The September 11, 2001, terrorist attacks on the World Trade Center (WTC) in New York City (9/11) had health-related consequences, including posttraumatic stress disorder (PTSD). PTSD is associated with functional impairment, which varies by symptom severity and other factors. This study aimed to identify predictors of functional impairment in individuals with low versus high PTSD symptom severity levels. WTC Health Registry enrollees exposed to 9/11 were surveyed four times between 2003 and 2015; cumulated data for individuals who endorsed at least one symptom on the PTSD Checklist–Civilian Version (PCL-C) at Wave 4 (2015–2016) were included (N = 30,287) and examined cross-sectionally. Individuals were classified based on PCL-C scores as having low/no (2–29) or high levels of PTSD symptom severity (≥ 44). Functional impairment was defined as subsequent difficulties in daily living. Among low/no PTSD severity participants, adjusted odds ratios (aORs) for the associations between functional impairment and poor self-rated health (vs. good), low social support (vs. high), and no physical activity (vs. active) were 1.23–1.92. In the same group, low versus high household income was associated with more functional impairment, aOR = 1.34, 95% CI [1.13, 1.59]. Among participants with high-level PTSD symptoms, women, aOR = 1.70, 95% CI [1.31, 2.20], and Hispanic enrollees, aOR = 1.76, 95% CI [1.31, 2.36], were more likely to report an absence of impairment. Self-rated health, social support, and physical activity emerged as important predictors of PTSD-related functional impairment across PTSD symptom severity levels, supporting clinical interventions targeting these factors.  相似文献   
76.
Extracorporeal shock wave lithotripsy (ESWL) is a well-established, safe and effective therapeutic modality for surgical treatment of urolithiasis. Hematoma is a rare complication of ESWL and, when it occurs, typically involves the kidney. We report the case of a 71-year-old woman who developed severe, persistent abdominal pain after ESWL for a 9-mm stone at the ureteropelvic junction. Post-treatment CT scan demonstrated a 13 × 6–cm subcapsular hepatic hematoma. A follow-up CT scan showed expansion of the hematoma and development of hepatic vein thrombosis. This finding, along with persistent abdominal pain and rising liver transaminases, led to surgical intervention. The patient''s symptoms resolved and liver function returned to baseline following liver decompression.  相似文献   
77.
BACKGROUND: Screening mammography has led to earlier diagnosis of breast cancer; however, the increased tissue density of young women can complicate mammographic interpretation. We hypothesized that magnetic resonance imaging (MRI) has value in detection of mammographically occult breast cancers, particularly in premenopausal women for whom the sensitivity of mammography is compromised. METHODS: Data were available for 89 women with biopsy-proven breast cancer who had undergone both mammography and breast MRI. Variables evaluated included menopausal status and radiographic findings. Data were analyzed using Fisher's Exact test; P < .05 was considered significant. RESULTS: Of the 89 women in our study, 69 were perimenopausal or postmenopausal and 20 were premenopausal at the time of diagnosis. The malignant lesion was identified on mammography and MRI for a majority of patients. One third of premenopausal women had negative mammography but positive MRI findings. CONCLUSIONS: Our findings support a role for breast MRI in supplementing conventional mammography for early detection of breast cancer in premenopausal women.  相似文献   
78.
PURPOSE: Obesity has become a health-care crisis in the United States. Adolescent obesity is now one of the most common childhood disorders, with 4.7 million American adolescents having a body mass index (BMI) greater than the 95th percentile. Most patients do not respond to diet modification or exercise programs and attention is now turning toward surgery as a source of weight loss in adolescents. Few studies have looked at the overall morbidity and mortality of weight loss surgery in this patient population. METHODS: This is a retrospective study of medical charts of 15 bariatric surgical procedures performed on 14 adolescents without known genetic syndromes associated with severe childhood obesity from 1971 to 2001 at the University of Minnesota. Procedures performed on these patients included vertical banded gastroplasty (n = 7), Roux-en-Y gastric bypass (n = 5), and jejunoileal bypass (n = 3). Jejunoileal bypass procedures were performed from 1971 to 1977, after which time this procedure was abandoned. Patient age ranged from 13 to 17 years (mean, 15.7 years). Mean follow-up time was 6 years, with 9 patients available for long-term follow-up. RESULTS: All procedures were performed using an open technique by 1 surgeon. There were no perioperative deaths; complications included 1 case of wound infection, 2 episodes of dumping syndrome that resolved without revision, 1 episode of hypoglycemia, and 1 case of short-term electrolyte imbalance in a patient who underwent jejunoileal bypass. The average BMI dropped from 58.5 +/- 13.7 to 32.1 +/- 9.7 kg/m(2) (P < .01)--a 45% reduction. CONCLUSIONS: Surgery for morbid obesity is safe and results in significant weight loss in adolescents who fail medical therapy.  相似文献   
79.
Adults with β thalassemia major frequently have low BMD, fractures, and bone pain. The purpose of this study was to determine the prevalence of low BMD, fractures, and bone pain in all thalassemia syndromes in childhood, adolescence, and adulthood, associations of BMD with fractures and bone pain, and etiology of bone disease in thalassemia. Patients of all thalassemia syndromes in the Thalassemia Clinical Research Network, ≥6 yr of age, with no preexisting medical condition affecting bone mass or requiring steroids, participated. We measured spine and femur BMD and whole body BMC by DXA and assessed vertebral abnormalities by morphometric X‐ray absorptiometry (MXA). Medical history by interview and review of medical records, physical examinations, and blood and urine collections were performed. Three hundred sixty‐one subjects, 49% male, with a mean age of 23.2 yr (range, 6.1–75 yr), were studied. Spine and femur BMD Z‐scores < ?2 occurred in 46% and 25% of participants, respectively. Greater age, lower weight, hypogonadism, and increased bone turnover were strong independent predictors of low bone mass regardless of thalassemia syndrome. Peak bone mass was suboptimal. Thirty‐six percent of patients had a history of fractures, and 34% reported bone pain. BMD was negatively associated with fractures but not with bone pain. Nine percent of participants had uniformly decreased height of several vertebrae by MXA, which was associated with the use of iron chelator deferoxamine before 6 yr of age. In patients with thalassemia, low BMD and fractures occur frequently and independently of the particular syndrome. Peak bone mass is suboptimal. Low BMD is associated with hypogonadism, increased bone turnover, and an increased risk for fractures.  相似文献   
80.
BACKGROUND: This study aimed to examine the validity of using Maryland hospital discharge data to characterize injuries sustained by trauma patients. METHODS: Maryland hospital discharge and Maryland trauma registry data for 1999 were merged, and the extent of agreement regarding the presence and severity of injuries sustained was evaluated. RESULTS: The mean Injury Severity Score was 8.4 according to the Maryland hospital discharge data and 10 according to the Maryland trauma registry data (p < 0.0001). The Maryland hospital discharge data identified 95% or more of all moderate to severe injuries (Abbreviated Injury Score, > or =2) for all body regions except the head. There was substantial agreement between the two data sets for mechanism of injury (weighted kappa, 0.62), the number of preexisting conditions present (weighted kappa, 0.45) and final disposition (weighted kappa, 0.78). CONCLUSIONS: The Maryland hospital discharge data are a valid source for documenting the nature and severity of injuries sustained by trauma patients, except for those with a relatively minor head injury.  相似文献   
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