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991.

Background

Umbilical venous catheterization is a common procedure performed in neonatal intensive care units. Hepatic collections due to inadvertent extravasation of parenteral nutrition into the liver have been described previously in literature.

Objective

To recognize the clinicoradiologic features and treatment options of hepatic collections due to inadvertent extravasation of parenteral nutrition fluids caused by malpositioning of umbilical venous catheter (UVC) in the portal venous system.

Materials and methods

This is a case series describing five neonates during a 6-year period at a single tertiary care referral center, with extravasation of parenteral nutrition into the liver parenchyma causing hepatic collections.

Results

All five neonates receiving parenteral nutrition presented with abdominal distension in the second week of life. Two out of five (40%) had anemia requiring blood transfusion and 3/5 (60%) had hemodynamic instability at presentation. Ultrasound of the liver confirmed the diagnosis in all the cases. Three of the five (60%) cases underwent US-guided aspiration of the collections, one case underwent conservative management and one case required emergent laparotomy due to abdominal compartment syndrome. US used in follow-up of these cases revealed decrease in size of the lesions and/or development of calcifications.

Conclusion

Early recognition of this complication, prompt diagnosis with US of liver and timely treatment can lead to better outcome in newborns with hepatic collections secondary to inadvertent parenteral nutrition infusion via malposition of UVC.  相似文献   
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Background: Platelet‐rich plasma (PRP) contains a number of biologically active growth factors, and previous studies have reported conflicting ridge augmentation results. The primary aim of this randomized, controlled, masked, clinical trial was to determine if PRP combined with a rapidly resorbing cancellous allograft would enhance the regenerative result compared with an allograft without PRP. Methods: Thirty‐two patients with an edentulous ridge defect were sequentially entered into the study; four were excluded from data analysis. Fourteen patients received a cancellous allograft (CAN group) and the other 14 received a cancellous allograft mixed with PRP (PRP group). All 28 grafted sites were covered with a resorbable polylactide membrane. After elevation of a full‐thickness flap, horizontal ridge dimensions were measured with a digital caliper at the crest and 5 mm apical to the crest. Vertical ridge dimensions were measured from a tooth‐supported stent. All sites were reentered at 4 months, and a trephine core was obtained for histologic analysis before implant placement. Results: The crestal ridge width for the CAN group had a mean gain of 2.0 ± 1.2 mm, whereas the PRP group gained 2.9 ± 1.0, and the difference was statistically significant between groups (P <0.05). The percent vital bone was 36% ± 14% for the CAN group compared with 51% ± 15% for the PRP group and was statistically significant between groups (P <0.05). Loss of augmented ridge width was 34% ± 17% for the CAN group and 28% ± 17% for the PRP group (P >0.05). Conclusion: These clinical and histologic findings suggest that PRP enhanced bone regeneration and resulted in increased horizontal bone gain and percentage vital bone.  相似文献   
996.
Objective: To compare the primary stability of miniscrews inserted into bone blocks of different bone mineral densities (BMDs) with and without cortical bone, and investigate whether some trabecular properties could influence primary stability.Materials and Methods:Fifty-two bone blocks were extracted from fresh bovine pelvic bone. Four groups were created based on bone type (iliac or pubic region) and presence or absence of cortical bone. Specimens were micro-computed tomography imaged to evaluate trabecular thickness, trabecular number, trabecular separation, bone volume density (BV/TV), BMD, and cortical thickness. Miniscrews 1.4 mm in diameter and 6 mm long were inserted into the bone blocks, and primary stability was evaluated by insertion torque (IT), mini-implant mobility (PTV), and pull-out strength (PS).Results:Intergroup comparison showed lower levels of primary stability when the BMD of trabecular bone was lower and in the absence of cortical bone (P ≤ .05). The Pearson correlation test showed correlation between trabecular number, trabecular thickness, BV/TV, trabecular BMD, total BMD, and IT, PTV, and PS. There was correlation between cortical thickness and IT and PS (P ≤ .05).Conclusion:Cancellous bone plays an important role in primary stability of mini-implants in the presence or absence of cortical bone.  相似文献   
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The brown macroalgae Bifurcaria bifurcata have gained special attention due to their ability to biosynthesize linear diterpenes (rarely found in other species). However, the conventional extraction methods normally used to extract these compounds involve organic solvents and often high temperatures, leading to the degradation of thermo-labile compounds. In this context, the main objective of this work was to study and optimize for the first time the extraction of diterpenes from B. bifurcata through an environmentally friendly methodology, namely, high pressure extraction (HPE) using ethanol : water. This was compared with conventional Soxhlet extraction, using dichloromethane. Box–Behnken design was employed to evaluate the linear, quadratic, and interaction effects of 3 independent variables (pressure (X1), ethanol percentage (X2), and time of extraction (X3)) on response variables (extraction yield and diterpenes content (mg g−1 of extract and mg kg−1 of dry weight)) and the optimal extraction conditions (X1: 600 MPa; X2: 80%; X3: 5 min) were estimated by response surface methodology (RSM). B. bifurcata extract obtained under HPE optimal conditions showed a diterpenes content (612.2 mg g−1 of extract) 12.2 fold higher than that obtained by conventional extraction (50.1 mg g−1 of extract). The HPE extract, obtained under optimal conditions, showed antioxidant and antibacterial (against Staphylococcus aureus) activities considerably higher than the Soxhlet extract, and also presented a promising synergic effect with antibiotics, improving the antibiotic efficacy against S. aureus. In conclusion, these results indicate that HPE is a promising methodology, compared to conventional methodologies to obtain linear diterpene rich extracts from B. bifurcata with great potential to be exploited in pharmaceutical or biomedical applications.

Bioactive linear diterpenes were selectively extracted from the macroalga Bifurcaria bifurcata through optimized high-pressure extraction.  相似文献   
999.

OBJECTIVE:

To epidemiologically characterize the population treated at our orthopedic clinic with a diagnosis of septic arthritic of the hip between 2006 and 2012.

METHODS:

Fifteen patients diagnosed with septic arthritis of the hip between 2006 and 2012 were retrospectively evaluated. The patients'' clinical and epidemiological characteristics were surveyed; a sensitivity profile relating to the microorganisms that caused the infections and the complications relating to the patients'' treatment and evolution were identified.

RESULTS:

Septic arthritis was more common among males. Most diagnoses were made through positive synovial fluid cultures, after joint drainage was performed using the Smith-Petersen route. Among the comorbidities found, the most prevalent were systemic arterial hypertension, diabetes mellitus, and human immunodeficiency virus. The pathological joint conditions diagnosed prior to joint infection were osteoarthrosis and developmental dysplasia of the hip. The infectious agent most frequently isolated was Staphylococcus aureus. From the clinical and laboratory data investigated, 53.33% of the cases presented with fever, and all except one patient presented with increased measures in inflammation tests. Gram staining was positive in only 26.66% of the synovial fluid samples analyzed. Six patients presented with joint complications after treatment was administered.

CONCLUSION:

S. aureus is the most common pathogen in acute infections of the hip in our setting. Factors such as clinical comorbidities are associated with septic arthritis of the hip. Because of the relatively small number of patients, given that this is a condition of low prevalence, there was no statistically significant correlation in relation to worse prognosis for the disease.  相似文献   
1000.

OBJECTIVES

: To evaluate the neuroprotective effect of epidural hypothermia in rats subjected to experimental spinal cord lesion.

METHODS:

Wistar rats (n = 30) weighing 320-360 g were randomized to two groups (hypothermia and control) of 15 rats per group. A spinal cord lesion was induced by the standardized drop of a 10-g weight from a height of 2.5 cm, using the New York University Impactor, after laminectomy at the T9-10 level. Rats in the hypothermia group underwent epidural hypothermia for 20 minutes immediately after spinal cord injury. Motor function was assessed for six weeks using the Basso, Beattie and Bresnahan motor scores and the inclined plane test. At the end of the final week, the rats'' neurological status was monitored by the motor evoked potential test and the results for the two groups were compared.

RESULTS:

Analysis of the Basso, Beattie and Bresnahan scores obtained during the six-week period indicated that there were no significant differences between the two groups. There was no significant difference between the groups in the inclined plane test scores during the six-week period. Furthermore, at the end of the study, the latency and amplitude values of the motor evoked potential test were not significantly different between the two groups.

CONCLUSION:

Hypothermia did not produce a neuroprotective effect when applied at the injury level and in the epidural space immediately after induction of a spinal cord contusion in Wistar rats.  相似文献   
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