Changes of brachial flow-mediated vasodilation in different ischemic stroke subtypes

The relationship between endothelial dysfunction and stroke subtypes is unclear. We prospectively measured brachial flow-mediated vasodilation (FMD) in 143 patients with acute ischemic stroke and 40 controls. The overall stroke patients had impaired FMD, but only lacunar infarction had significantly impaired FMD vs the controls. Impaired FMD was an independent predictor for lacunar infarction. Ischemic stroke is associated with endothelial dysfunction, which is more conspicuous in lacunar infarction.     

Aggressive Surgical Approach for Patients with T4 Gastric Carcinoma: Promise or Myth?

Background

Surgical outcomes of multiorgan resection (MOR) for T4 gastric carcinoma reported in the literature are widely variable. We herein report a large surgical series of T4 gastric carcinoma.

Methods

One hundred seventy-nine patients with cT4 gastric carcinoma were recruited onto the study. Patient characteristics, surgical strategy and related complications, long-term survival, and prognostic factors of T4 gastric carcinoma were analyzed.

Results

Of 179 cT4 gastric carcinoma, there were 57 cT4 (pT3) with MOR, 91 pT4 with MOR, and 31 cT4 without MOR. pT4 with MOR were more likely to be associated with nodal metastasis, cellular dedifferentiation, and lymphoperineural infiltration compared to those of pT0–3 (P < 0.01 for all). For 91 pT4 with MOR, their surgical mortality and morbidity rates were 4.4 and 28.6%, respectively; their 1-, 3-, and 5-year overall survival rates were 55.2, 22.4, and 12.2%, respectively. The long-term survival of cT4 (pT3) with MOR was superior to pT4 with MOR (P = 0.006) and cT4 without MOR (P = 0.004). There was a striking difference between pT4 with MOR, R0 and pT4 with MOR, and R1 or R2 (P = 0.007). By means of multivariate analysis, lymph node status, liver invasion, and positive surgical margin were independent prognostic factors.

Conclusions

Aggressive surgical management of pT4 gastric carcinoma should be limited to patients without adverse prognostic factors such as advanced nodal involvement and pancreatic invasion.     

Determinants of outcome in elderly patients with positive sentinel lymph nodes

Background

Older women are less likely to receive standard of care treatment for breast cancer.

Methods

We examined variables that affected the outcome of elderly patients ≥70 years old among 1,470 patients with invasive cancer with positive sentinel lymph nodes (SLNs).

Results

Elderly patients were less likely to undergo mastectomy, completion axillary node dissection (ALND), adjuvant chemotherapy, and radiotherapy (RT) following breast-conserving therapy (BCT) compared with patients <70 years old. The 5-year risk of disease progression and cumulative incidence of breast cancer–specific deaths were not significantly different for both groups. On multivariate analysis, hormone receptor–negative status, number of metastatic lymph nodes, high nuclear grade, and tumor size were the factors independently associated with increased risk of disease progression.

Conclusions

Tumor factors were the primary determinants of breast cancer outcomes in our cohort. Elderly patients are less likely to receive aggressive surgical interventions and adjuvant therapy because of perceived life expectancy.     

Hybrid combination of small subxiphoid incision and thoracoscopic thymectomy for juvenile myasthenia gravis

Background/Purpose

Myasthenia gravis is an autoimmune disease that usually responds positively to treatment with thymectomy. Various approaches via video-assisted thoracic thymectomy as a substitute for conventional sternotomy have been reported. We reported a less invasive technique for thymectomy in pediatric groups.

Methods

Four adolescents with juvenile myasthenia gravis all underwent hybrid combination of small subxiphoid incision and thoracoscopic thymectomy at our institute. Clinical characteristics and surgical outcome were consecutively collected.

Results

In these 4 patients, 2 presented with Osserman class III and 2 with class IIb. The mean operative time was 180 minutes. There was no conversion to sternotomy, and there was only minimal blood loss. Follow-up duration was 3 to 64 months. Postoperatively, 1 patient had complete remission and 3 patients had improvement in clinical symptoms.

Conclusion

Hybrid combination of small subxiphoid incision and thoracoscopic thymectomy may be an effective alternative with low surgical invasiveness for treating juvenile myasthenia gravis.     

A contemporary analysis of parenteral nutrition-associated liver disease in surgical infants

Background/purpose

Despite advances in pediatric nutritional support and a renewed focus on management of intestinal failure, there are limited recent data regarding the risk of parenteral nutrition (PN)-associated liver disease in surgical infants. This study investigated the incidence of cholestasis from PN and risk factors for its development in this population.

Methods

A retrospective review was performed of all neonates in our institution who underwent abdominal surgery and required postoperative PN from 2001 to 2006. Cholestasis was defined as 2 conjugated bilirubin levels greater than 2 mg/dL over 14 days. Nonparametric univariate analyses and multivariate logistic regression were used to model the likelihood of developing cholestasis. Median values with range are presented.

Results

One hundred seventy-six infants met inclusion criteria, and patients received PN for 28 days (range, 2-256 days). The incidence of cholestasis was 24%. Cholestatic infants were born at an earlier gestational age (34 vs 36 weeks; P < .01), required a 3-fold longer PN duration (76 vs 21 days; P < .001), had longer inpatient stays (86 vs 29 days; P < .001), and were more likely to be discharged on PN. The median time to cholestasis was 23 days. Cholestasis was an early development; 77% of cholestatic infants developed cholestasis by 5 weeks of PN exposure. On multivariate regression, only prematurity was significantly associated with development of cholestasis (P < .05).

Conclusion

In this analysis, the development of PN-associated liver disease occurred early in the course of exposure to PN. These data help to define the time course and prognosis for PN-associated cholestasis in surgical infants.     

Downregulation of the antioxidant protein peroxiredoxin 2 contributes to angiotensin II-mediated podocyte apoptosis

Podocytes have a significant role in establishing selective permeability of the glomerular filtration barrier. Sustained renin-angiotensin-aldosterone system activation is crucial to the pathogenesis of podocyte injury, but the mechanisms by which angiotensin II modulates podocyte survival due to physiological or injurious stimuli remain unclear. Here, we used proteomic analysis to find new mediators of angiotensin II-induced podocyte injury. Antioxidant protein peroxiredoxin 2 expression was decreased in cultured podocytes stimulated with angiotensin II. Peroxiredoxin 2 was found to be expressed in podocytes in vivo, and its expression was decreased in the glomeruli of rats transgenic for angiotensin II type 1 receptors in a podocyte-specific manner, or in rats infused with angiotensin II. Downregulation of peroxiredoxin 2 in podocytes resulted in increased reactive oxygen species release, protein overoxidation, and inhibition of the Akt pathway. Both treatment with angiotensin II and downregulation of peroxiredoxin 2 expression led to apoptosis of podocytes. Thus, peroxiredoxin 2 is an important modulator of angiotensin II-induced podocyte injury.     

The role of reactive oxygen species scavenging enzymes in the development of septic loosening after total hip replacement

In this study of 41 patients, we used proteomic, Western blot and immunohistochemical analyses to show that several reactive oxygen species scavenging enzymes are expressed differentially in patients with primary osteoarthritis and those with non-loosening and aseptic loosening after total hip replacement (THR). The patients were grouped as A (n = 16, primary THR), B (n = 10, fixed THR but requiring revision for polyethylene wear) and C (n = 15, requiring revision due to aseptic loosening) to verify the involvement of the identified targets in aseptic loosening. When compared with Groups A and B, Group C patients exhibited significant up-regulation of transthyretin and superoxide dismutase 3, but down-regulation of glutathione peroxidase 2 in their hip synovial fluids. Also, higher levels of superoxide dismutase 2 and peroxiredoxin 2, but not superoxide dismutase 1, catalase and glutathione perioxidase 1, were consistently detected in the hip capsules of Group C patients. We propose that dysregulated reactive oxygen species-related enzymes may play an important role in the pathogenesis and progression of aseptic loosening after THR.     

Measurement of hearing aid outcome in the elderly: Comparison between young and old elderly

OBJECTIVE: To evaluate speech performance and subjective outcomes for older individuals who have hearing impairment and use digital hearing aids. The outcomes between young and old elderly users were compared. STUDY DESIGN: Prospective. SUBJECTS AND METHODS: Fifty-nine patients with hearing loss fitted with digital hearing aids were included. They were divided into two groups. Group A consisted of 32 subjects aged 65 to 80 years, whereas group B had 27 subjects older than 80 years. Speech performance and subjective outcomes were measured 4 months after fitting of hearing aids. Hearing Handicap Inventory for the Elderly-Screening Version (HHIE-S), Client Oriented Scale of Improvement (COSI), satisfaction, and usage questionnaires were used as subjective assessments. RESULTS: Improvements in speech performance were not significantly different between these two groups. There were no statistical differences in terms of HHIE-S score reduction, satisfaction rate, daily usage time, and COSI scores between both groups. CONCLUSION: Age by itself is not a limiting factor for older patients with hearing impairment to benefit from digital hearing aids.     

Increasing bending strength and pullout strength in conical pedicle screws: biomechanical tests and finite element analyses

STUDY DESIGN: Comparative in vitro biomechanical study and finite element analysis. OBJECTIVES: To investigate the bending strength and pullout strength of conical pedicle screws, as compared with conventional cylindrical screws. SUMMARY OF BACKGROUND DATA: Transpedicle screw fixation, the gold standard of spinal fixation, is threatened by screw failure. Conical screws can resist screw breakage and loosening. However, biomechanical studies of bending strength have been lacking, and the results of pullout studies have varied widely. METHODS: Ten types of pedicle screws with different patterns of core tapering and core diameter were specially manufactured with good control of all other design factors. The stiffness, yielding strength, and fatigue life of the pedicle screws were assessed by cantilever bending tests using high-molecular-weight polyethylene. The pullout strength was assessed by pullout tests using polyurethane foam. Concurrently, 3-dimensional finite element models simulating these mechanical tests were created, and the results were correlated to those of the mechanical tests. RESULTS: In bending tests, conical screws had substantially higher stiffness, yielding strength, and fatigue life than cylindrical screws (P<0.01), especially when there was no step at the thread-shank junction. In pullout tests, pullout strength was higher in screws with a conical core and smaller core diameter and also in situations with higher foam density (P<0.01). In finite element analysis, the maximal deflection and maximal tensile stress were closely related to yielding strength (r=-0.91) and fatigue life (r=-0.95), respectively, in the bending analyses. The total reaction force was closely related to the pullout strength in pullout analyses (r=0.84 and 0.91 for different foam densities). CONCLUSIONS: Conical screws effectively increased the bending strength and pullout strength simultaneously. The finite element analyses reliably predicted the results of the mechanical tests.