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991.

Background

Patent ductus arteriosus (PDA) is a condition that commonly affects premature and low birth weight (BW) infants at times necessitating surgical intervention. We examined outcomes after surgical ligation (SL).

Materials and methods

We analyzed the Kids' Inpatient Database for premature infants diagnosed with PDA, admitted at <8 d of age. Patient demographics, disposition, morbidity, and mortality were analyzed. All cases were weighted appropriately to project nationally representative estimates.

Results

A total of 63,208 patients were identified with diagnosis of PDA. Of these, 6766 (10.7%) underwent SL. Lower gestational age (GA) and BW patients had higher incidence of PDA and rates of SL. Overall survival was 90.8% for the cohort. Survival for the SL group was 88.0% and 91.2% for the non-SL group; however, infants undergoing SL had higher survival rates up to 28 wk and 1250 g for GA and BW, respectively. GA did not affect post-SL survival adversely. Rather, lower BW was associated with extremely high mortality rates. Black infants and boys had lower survival compared with other races and girls, respectively. Larger hospitals had higher survival rates, but hospital location, teaching status, and type did not affect survival. Payer status and income quartile did not affect survival.

Conclusions

PDA and SL are more common in lower BW and GA groups. Higher survival rates are found for infants with SL versus non-SL in the lowest BW and GA groups. Morbidity and mortality are not affected by SL timing. BW, rather than GA, determines survival of infants undergoing SL.  相似文献   
992.

Background

Proliferation of vascular smooth muscle cells (VSMCs) is a crucial event in the pathogenesis of intimal hyperplasia, which is the main cause of restenosis after vascular reconstruction. In this study, we assessed the impact of let-7a microRNA (miRNA) on the proliferation of VSMCs.

Methods

Using miRNA microarrays analysis for miRNA expression in the vein graft model. Lentiviral vector-mediated let-7a was transfected into the vein grafts. In situ hybridization was performed to detect let-7a. Cultured rat VSMCs were transfected with let-7a mimics for different periods of time. Cell proliferation, migration and cell cycle activity were monitored following transfection of the let-7a mimics. Immunohistochemical and Western blotting analysis the expression levels of c-myc and K-ras.

Results

We found that let-7a was the most downregulated miRNA in the vein graft model. In vivo proliferation of VSMCs was assessed in a rat model of venous graft intimal hyperplasia. Let-7a was found to localize mainly to the VSMCs. Let-7a miRNA expression was increased in VSMCs in the neointima of the let-7a treated group. Intimal hyperplasia was suppressed by upregulation of let-7a via lentiviral vector-mediated mimics. In cultured VSMCs, the expression of let-7a increased upon starving, and the upregulation of let-7a miRNA significantly decreased cell proliferation and migration. Immunohistochemical and Western blotting analysis demonstrated that treatment with let-7a mimics resulted in decreased expression levels of c-myc and K-ras.

Conclusions

The results indicate that let-7a miRNA is a novel regulator of VSMC proliferation in intimal hyperplasia. These findings suggest that let-7a miRNA is a promising therapeutic target for the prevention of intimal hyperplasia.  相似文献   
993.

Background

The aim of this study was to assess whether intraperitoneal administration of ginseng total saponins (GTS) has antihyperalgesic effects in a rat model of incisional pain. The proinflammatory responses and reversal of the antihyperalgesic effect of GTS by N-methyl-d-aspartate (NMDA) or naloxone were also evaluated.

Materials and methods

Rats were injected intraperitoneally with 0.9% saline vehicle or various doses of GTS before or after a plantar incision. Paw withdrawal in response to application of the von Frey filament with the lowest bending force marked the mechanical withdrawal threshold (MWT). Blood samples were collected for the assessment of serum interleukin (IL)-1β and IL-6 levels. The IL levels were measured using an enzyme-linked immunosorbent assay kit. Rats were injected intraperitoneally with NMDA or naloxone before the GTS injection to assess the reversal of the antihyperalgesic effect of GTS.

Results

The MWT measured 2 h after the plantar incision increased significantly after the postincision administration of 50, 100, or 200 mg/kg of GTS compared with the MWT at 2 h after plantar incision. The MWT also increased significantly after the preincision injection of 100 or 200 mg/kg of GTS compared with the MWT of the vehicle control. Administration of GTS suppressed the postincision rise in serum IL-1β levels and NMDA inhibited the increase in the MWT compared with GTS alone.

Conclusions

Intraperitoneal administration of GTS before or after surgery induces antihyperalgesic effects in a rat model of incisional pain. The effects on mechanical hyperalgesia may be associated with anti-inflammatory cytokines and NMDA signaling.  相似文献   
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Motor function changes in the unaffected hand of stroke patients with hemiplegia. These changes are often ignored by clinicians owing to the extent of motor disability of the affected hand. Finger tapping frequency and Lind-mark hand function score showed that the motor function of unaffected hands in stroke patients was poorer than that of a healthy control hand. After 2 weeks of rehabilitation treatment, motor function of the unaffected hand of stroke patients was obviously improved. Therefore, attention should also be paid to motor function in the unaffected hand of stroke patients with hemiplegia during rehabilitation.  相似文献   
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