Systemic hemodynamic effects of norepinephrine versus phenylephrine in intermittent bolus doses during spinal anesthesia for cesarean delivery.

BACKGROUND: Norepinephrine, a potent α-adrenergic agonist with ß-adrenergic effects, has recently emerged as a potential alternative to phenylephrine that does not lower cardiac output (CO) and heart rate (HR) during cesarean deliveries. We examined the systemic hemodynamic effects of both agents in this setting, using intermittent bolus doses to treat spinal anesthesia-induced hypotension. METHODS: A total of 56 parturients consenting to spinal anesthesia for elective cesarean delivery were randomly assigned to phenylephrine (100 µg/ml) or norepinephrine (5 µg/ml) intermittent bolus dosing. The primary study outcome was maternal normalized CO, examining and other hemodynamic variables, maternal side effects, and fetal outcomes secondarily. RESULTS: In terms of systolic blood pressure and HR, there were significant within-group differences over time (P < 0.001 and P < 0.001, respectively). Normalized CO and stroke volume (SV) also showed significant differences between groups (P < 0.001 and P = 0.002, respectively). In the phenylephrine group, normalized CO and SV declined (relative to baseline values) by as much as 13% and 9%, respectively; whereas in the norepinephrine group, normalized CO did not differ significantly from baseline, and SV increased up to 5% (relative to baseline). Normalized total peripheral resistance likewise displayed significant within-group differences over time (P < 0.001). CONCLUSIONS: During elective cesarean delivery, intermittent bolus doses of norepinephrine proved effective for treating spinal anesthesia-induced hypotension, while maintaining CO and SV. No maternal complications or fetal effects were evident.

Pneumocephalus following fluoroscopy-guided lumbar epidural injection in elderly patients: two cases report and a review of Korean literatures - Two cases report.

BACKGROUND: Pneumocephalus can originate from accidental dural puncture while performing epidural block using the loss-of-resistance (LOR) technique with an air-filled syringe. CASE: We present two cases of pneumocephalus after lumbar epidural block under fluoroscopy for pain control in elderly patients. CONCLUSIONS: Lumbar epidural block should be performed under fluoroscopic guidance in elderly patients with severe lesions. The physician should be aware of the increased possibility of a dural puncture occurring due to anatomical changes in older patients. The use of saline is recommended for the LOR technique. A contrast injection should be used together with the LOR technique to locate the epidural space. If a dural puncture occur, the patient should be carefully monitored to determine whether pneumocephalus has developed.

Evaluating Tidal Volume Delivered by a Self-Inflating Bag Depending on the Compression Method.

BACKGROUND: A self-inflating bag (SIB) is an essential device for pulmonary resuscitation in emergencies. However, it is difficult for a rescuer to accurately predict a tidal volume (TV) delivered by a SIB to a patient. OBJECTIVE: The objective of this study was to evaluate TV values delivered by a SIB with various compression methods. METHODS: A total of 33 participants were enrolled in this study. Anterior, middle, and posterior points were marked on the surface of the SIB to guide participants to place their fingers. This was connected to a gas-flow analyzer and a test lung to measure the TV. Participants were asked to squeeze the SIB with one-handed and two-handed compression at anterior, middle, and posterior points. RESULTS: The TV was the largest when the bag was squeezed with two-handed compression at the middle points (578 ± 21 mL). It was the smallest when the bag was squeezed with one-handed compression at the anterior point (311 ± 15 mL). Except that the TV with one-handed compression at the middle point and the TV with two-handed compression at the posterior points were similar, all other TV values were significantly different from each other (all p ＜ 0.001). CONCLUSION: The TV delivered by a SIB could differ greatly depending on the compression points and whether one or two hands are used. Therefore, a rescuer should choose an appropriate compression method considering patient's physical characteristics and medical conditions.

The Effect of BN Reinforcement on the Mechanical Properties of Nanostructured Al2O3 Ceramics.

In spite of many attractive properties, the low fracture toughness of Al2O3 ceramic below ductilebrittle transition temperature limits its wide application in industry. One of the most obvious methods to improve the fracture toughness has been to add reinforcing compounds to fabricate nanostructured composite materials. In this respect, BN was evaluated as the reinforcing agent of Al2O3 ceramics using pulsed current activated sintering (PCAS). Highly dense alumina-BN composites with a relative density of up to 100% were achieved within short periods (2 min) by PCAS under a 80 MPa pressure. The rapid sintering method allowed the retention of the nanostructure by inhibiting the grain growth. The grain size of alumina was reduced remarkably by the addition of BN. The addition of BN to Al2O3 ceramic simultaneously improved the hardness and fracture toughness of alumina-BN composite.

The Effect of Ball Milling on Properties and Consolidation of Nanostructured ZrB2.

ZrB2 powders were milled using high-energy ball for various durations and consolidated using the pulsed current activated sintering (PCAS). The effects of milling on the sintering behavior and crystallite size ZrO2 powders were investigated. A nanostructured dense ZrB2 specimen with a relative density of up to 97% was readily achieved within 3 min. The ball milling effectively refined the crystallite structure of ZrB2 powders and facilitated the subsequent consolidation. The sinter-onset temperature was reduced appreciably by the prior milling for 10 h. Accordingly, the relative density of ZrB2 compact increases as the milling time increases. The hardness and fracture toughness of sintered ZrB2 increased as the density increases.

The Clinical Characteristics of Spinal Epidural Lipomatosis in the Lumbar Spine.

BACKGROUND: Spinal epidural lipomatosis (SEL) is a rare disease, defined as diffuse hypertrophy of unencapsulated adipose tissue causing spinal canal compression and progressive neurologic deficits. However, there are few studies on SEL in Korea. OBJECTIVES: The purpose of this study was to describe the prevalence and clinical characteristics of SEL in Korea. METHODS: Of the 3702 symptomatic patients (1575 males and 2127 females) who underwent lumbar spine magnetic resonance imaging (MRI) at the age of 20 years or older from January 2014 to December 2016, 42 patients (27 males and 15 females) diagnosed with SEL were selected. Medical records and telephone counseling were used to document sex, age, height, weight, clinical symptoms, coexistent spinal disease, accompanying diseases, and alcoholism and smoking status. One radiologist classified the severity of epidural lipomatosis into three grades from I to III according to Borre et al. We obtained four linear measurements at the axial plane parallel based in the narrowest on MRI image. RESULTS: The incidence of SEL in the lumbar spine was 1.1%, which was 1.71% in men and 0.7% in women. The mean age was 69.4 ± 10.9 years and the mean body mass index (BMI) was 26.4 ± 3.5 kg/m2. The most common clinical symptoms were lower back pain and radiating leg pain (26 patients, 61.9%). The level of affected SEL was found to be most prevalent at L5 - S1 (21 patients, 50%). Concomitant diseases were hypertension (26 patients, 61.9%) and diabetes (12 patients, 28.5%). The most common SEL grade was type III (21 patients, 50%), followed by types II (17 patients, 40.4%) and I (4 patients, 9.5%). CONCLUSIONS: Lumbar spine MRI at one hospital showed that the incidence of symptomatic SEL was 1.1%; SEL is common at the L5-S1 level and in male patients, and severity grade is often severe.

Guided Bone Regeneration Using Demineralized Dentin Matrix: Long-Term Follow-Up.

PURPOSE: This case report reviews the long-term clinical outcomes of using demineralized dentin matrix (autogenous tooth bone graft material [AutoBT]) in 5 cases that were first reported in 2010. MATERIALS AND METHODS: Cone-beam computerized tomography was used to measure the height and width of the graft to determine the change in bone area from immediately after surgery to final follow-up (average, 5 yr 5.8 months). Corticocancellous bone formation and marginal bone resorption also were evaluated histologically 3 to 6 months after grafting, which focused mainly on remodeling capacities. RESULTS: Decreases in buccal height and alveolar ridge width ranged from -0.4 to -3.3 mm and from -0.4 to -4.2 mm, respectively. The change in bone area ranged from -8.1 to -36.2%. Corticocancellous bone had formed and was maintained successfully except for 1 mm of buccal marginal bone resorption in 1 case followed for 6 years 7 months. CONCLUSION: AutoBT, which was first reported for guided bone regeneration, showed that the corticocancellous bone that had formed had been maintained successfully with an implant after an average follow-up of 5 years. Although the number of samples was small, the results were consistent with those of other short-term follow-up studies on AutoBT.

Autogenous tooth bone graft block for sinus augmentation with simultaneous implant installation: a technical note.

In cases of severe alveolar bone atrophy in the posterior maxillary area, which has only a thin sinus floor, the autogenous tooth bone graft block (ABTB) was used to wrap the implant to enhance its primary stability and osseointegration in the sinus. These cases with four years of clinical follow-up demonstrate the applicability of the ABTB in maxillary sinus membrane elevation to improve the outcomes of implant placement.

Single-material zinc sulfide bi-layer antireflection coatings for GaAs solar cells.

We demonstrated the efficiency improvement of GaAs single-junction (SJ) solar cells with the single-material zinc sulfide (ZnS) bi-layer based on the porous/dense film structure, which was fabricated by the glancing angle deposition (GLAD) method, as an antireflection (AR) coating layer. The porous ZnS film with a low refractive index was formed at a high incident vapor flux angle of 80° in the GLAD. Each optimum thickness of ZnS bi-layer was determined by achieving the lowest solar weighted reflectance (SWR) using a rigorous coupled-wave analysis method in the wavelength region of 350-900 nm, extracting the thicknesses of 20 and 50 nm for dense and porous films, respectively. The ZnS bi-layer with a low SWR of ~5.8% considerably increased the short circuit current density (J(sc)) of the GaAs SJ solar cell to 25.57 mA/cm(2), which leads to a larger conversion efficiency (η) of 20.61% compared to the conventional one without AR layer (i.e., SWR~31%, J(sc) = 18.81 mA/cm(2), and η = 14.82%). Furthermore, after the encapsulation, its J(sc) and η values were slightly increased to 25.67 mA/cm(2) and 20.71%, respectively. For the fabricated solar cells, angle-dependent reflectance properties and external quantum efficiency were also studied.

Fluid extravasation caused by bladder perforation during bipolar transurethral resection using saline solution -a case report-.

Transurethral resection of the prostate is the gold standard in the operative management of benign prostatic hyperplasia. Bipolar transurethral resection of the prostate using saline solution is a safe technique and reduces the risk of transurethral resection syndrome. This report discusses a rare complication of bipolar transurethral resection of the prostate: the extravasation of 0.9% saline solution into intraperitoneal and retroperitoneal cavities due to bladder perforation, resulting in respiratory difficulties.

Cervical myelopathy due to single level prolapsed disc and spondylosis: a comparative study on outcome between two groups.

This article describes a retrospective study on myelopathy, induced by monosegmental prolapsed disc and spondylosis. To assess pre- and postoperative clinical and radiological findings related to myelopathy, and factors influencing the outcome, 20 disc herniation (group A) and 11 spondylosis patients (group B) were studied. Average duration of myelopathy in groups A and B were 3 and 8.7 months, respectively. Anterior decompression and fusion were performed. Pre- and postoperative clinical and radiological findings and outcomes were assessed. Average preoperative disc heights were 85.9% of normal in group A and 72.7% in group B. Average anteroposterior canal diameter and Pavlov ratio at diseased level were 13.9 mm and 0.81 in group A, respectively, and 12.1 mm and 0.78 in group B. Five group A (25.0%) and four group B cases (36.4%) had radiculopathy. Cord compressions among 20 group A patients were median in seven and paramedian in 13. In the 11 group B patients, nine were median and two were paramedian. High signal intensity was observed in 19 group A and ten group B patients. Postoperative regression of T(2)-weighted high signal intensity in 14 group A (73.7%) and two group B patients (20.0%) was observed. Preoperative JOA scores in groups A and B were 10.3 and 12.8, respectively, which became 66.2 and 22.5 postoperatively. Neurological recovery was poorer in group B than in group A. Outcome was influenced by chronicity of myelopathy.

A case of back pain caused by Salmonella spondylitis -A case report-.

Salmonella spondylitis is a rare illness, and it generally occurs in patients who have already had sickle cell anemia, and it is even rarer in patients who are without sickle cell anemia. A 61-year-old male patient was hospitalized for the evaluation of his renal function and then treatment was started for his back pain. His back pain had developed about 2 months previously without any specific trauma. Only a bulging disc was detected on the initial lumbar MRI. Regarding his fever, it was diagnosed as possible atypical pneumonia, scrub typhus, etc., and multiple antibiotic therapy was administered. At the time of transfer, the leucocytes and hs-CRP were normal and the ESR was elevated. A diagnostic epidural block was performed for his back pain, but his symptoms were not improved. Lumbar MRI was performed again and it showed findings of infective spondylitis. Salmonella D was identified on the abscess culture and so he was diagnosed as suffering from Salmonella spondylitis. After antibiotic treatment, his back pain was improved and the patient was able to walk.

Surgical correction of fixed kyphosis.

STUDY DESIGN: A retrospective review was carried out on 23 patients with rigid fixed kyphosis who underwent surgical correction for their deformity. PURPOSE: To report the results of surgical correction of fixed kyphosis according to the surgical approaches or methods. OVERVIEW OF LITERATURE: Surgical correction of fixed kyphosis is more dangerous than the correction of any other spinal deformity because of the high incidence of paraplegia. METHODS: There were 12 cases of acute angular kyphosis (6 congenital, 6 healed tuberculosis) and 11 cases of round kyphosis (10 ankylosing spondylitis, 1 Scheuermann's kyphosis). Patients were excluded if their kyphosis was due to active tuberculosis, fractures, or degenerative lumbar changes. Operative procedures consisted of anterior, posterior and combined approaches with or without total vertebrectomy. Anterior procedure only was performed in 2 cases, while posterior procedure only was performed in 8 cases. Combined procedures were used in 13 cases, including 4 total vertebrectomies. RESULTS: The average kyphotic angle was 71.8 degrees preoperatively, 31.0 degrees postoperatively, and the average final angle was 39.2 degrees . Thus, the correction rate was 57% and the correction loss rate was 12%. In acute angular kyphosis, correction rate of an anterior procedure only was 71%, correction rate of the combined procedures without total vertebrectomy was 49% and correction rate of the combined procedures with total vertebrectomy was 60%. In round kyphosis, correction rate of posterior procedure only was 65% and correction rate of combined procedures was 59%. The clinical results according to the Kirkaldy-Willis scale demonstrated 17 excellent outcomes, 5 good outcomes and one poor outcome. CONCLUSIONS: Our data indicates that the combined approach and especially the total vertebrectomy showed the safety and the greatest correction rate if acute angular kyphosis was greater than 60 degrees.

Cervical myelopathy secondary to atlas hypoplasia - reports of 3 adult cases -.

There have been paucity of reports on atlas hypoplasia, and as a result this condition is not clearly defined, nor well understood. The authors reported three cases of atlas hypoplasia that were found in adults who presented with myelopathic symptoms. On radiographic examination, it was found that the anterior-posterior diameter of the atlas was remarkably narrower in all three cases in comparison with normal persons. The MRI in all three cases also revealed intramedullary high signal lesions at the levels where severe spinal cord compression was present. This led to our diagnosis of atlas hypoplasia causing myelopathy.

Expression and distribution of thioredoxin and thioredoxin reductase in human nasal mucosa and nasal polyp.

CONCLUSIONS: The results of this study indicate that thioredoxin (Trx) and thioredoxin reductase (TrxR) may play a role in the defense of normal human nasal mucosa against external noxious stimuli. Based on the fact that normal nasal mucosa is continuously exposed to inhaled toxicants and contains a considerable number of inflammatory cells, Trx and TrxR may be upregulated even in normal nasal mucosa and perhaps the difference in their expression levels between normal nasal mucosa and nasal polyp, if it exists at all, is small and therefore difficult to detect. Further studies will be needed to clarify the roles of Trx and TrxR in the pathogenesis of nasal polyp. OBJECTIVES: The cellular antioxidant defense system includes thiol-containing proteins such as Trx and TrxR, which have recently attracted much attention due to their strong antioxidant radical quenching capabilities and other important biological functions related to the regulation of the cellular redox state. This study was undertaken to investigate the expression and distribution of Trx and TrxR in normal human nasal mucosa and nasal polyp, and to improve understanding of the significance of the Trx system in these conditions. MATERIAL AND METHODS: The expression and distribution of Trx and TrxR in normal human inferior turbinate mucosa and nasal polyp were investigated using reverse transcriptase polymerase chain reaction (RT-PCR), semiquantitative RT-PCR, Western blotting and immunohistochemistry. RESULTS: mRNAs and protein for both Trx and TrxR were detected in normal human inferior turbinate mucosa and nasal polyp. Semiquantitative RT-PCR and Western blotting revealed that there was no significant difference in the expression levels of Trx and TrxR between inferior turbinate mucosa and nasal polyp. Immunoreactivity for both Trx and TrxR was seen in nasal epithelial cells, glands and vascular endothelium of inferior turbinate mucosa and nasal polyp. Trx and TrxR immunoreactivity was also found in inflammatory infiltrating cells in inferior turbinate mucosa and nasal polyp.

Expression and distribution of ion transport mRNAs in human nasal mucosa and nasal polyps.

CONCLUSIONS: Our results indicate that the electrogenic kidney Na(+)/HCO(3)(-) cotransporter (kNBC), KCl cotransporter (KCC1 and -4) and Ca(2+)-activated Cl(-) channel (CaCC1, -2, -3) mRNAs are expressed in normal nasal mucosa and nasal polyp, suggesting that altered expression of all CaCC mRNAs in nasal polyp may cause impaired electrolyte and water transport across the epithelial cells. OBJECTIVE: Electrolyte transport by nasal epithelia has been suggested to be important for controlling the quantity and composition of the nasal fluid and may play an important role in the development of nasal polyps. Transepithelial transport of ions and water in various fluid-transporting epithelia is strictly dependent on the localization of specific membrane proteins in the polarized epithelial cells. In this study we investigated the expression and distribution of mRNA transcripts for kNBC, pancreatic NBC, KCC1, -2, -3, -4 and CaCC1, -2, -3 gene families in human nasal mucosa and nasal polyp. MATERIAL AND METHODS: The expression and localization of these gene families were investigated in inferior turbinate tissues and nasal polyp using reverse transcriptase polymerase chain reaction (RT-PCR), semiquantitative RT-PCR and in situ hybridization. RESULTS: mRNAs for kNBC, KCC1 and -4 and all the CaCC families (CaCC1, -2 and -3) are expressed in human turbinate mucosa and nasal polyp. The expression levels of kNBC and KCC1 and -4 mRNAs did not differ between nasal mucosa and nasal polyp. However, the expression levels of all the CaCC genes were significantly decreased in nasal polyp. In situ hybridization revealed that the expression of these genes was mainly localized in the epithelial layer and submucosal glands of inferior turbinate mucosa and in the epithelial layer of nasal polyp.

Biological activity in traditional Alaska pollack sikhae during low temperature fermentation.

Biological activity was examined on Alaska pollack sikhae produced with 4 treatments (by irradiating at 5 or 10 kGy, or by adding either 0.1 or 0.3% of chitooligosaccharide), compared with control (2-step fermentation only) during fermentation at -2 degrees C. The extracts (500 ppm level) of sikhae had antimicrobial activities against 4 different strains of food poisoning bacteria such as Staphy. aureus, B. subtilis, B. cereus, and L. monocytogenes. Antioxidative activity (EDA(50), 11.55 mg/mL) in control group increased with time up to 60 days of fermentation but decreased thereafter, while those levels in other products were kept within 10.60-18.30 mg/mL ranges during fermentation. Inhibitory activity of angiotensin-I converting enzyme (ACE) (IC(50), 1.51-2.89 mg/mL) in all products was observed during fermentation except at 0 day. Inhibitory activity of xanthine oxidase (XO) (IC(50), 0.65-0.87 mg/mL) in all products also increased with time up to 30 days of fermentation. Without irradiating or adding of chitooligosaccharide, Alaska pollack sikhae showing biological activities was enough by 2-step fermentation and storage at -2 degrees C only.