Effects of perfluorochemical evaporative properties on oxygenation during partial liquid ventilation

BACKGROUND: The physical-chemical properties of perfluorochemical (PFC) liquids have been shown to influence physiological and cellular responses during partial liquid ventilation (PLV). The aim of this study is to compare the relationship between patho-physiological endpoints and the physical properties of three PFC liquids used in treating acute lung injury. METHODS: A total of 18 juvenile rabbits were randomized into conventional mechanical ventilation or PLV groups after lung saline lavages. Three PFC liquids, including Flutec perfluoro-1,3,5-trimethylcyclohexane (PP4; vapor pressure, 28.8 mmHg at 37 degrees C), Perfluorodecalin (PFD; vapor pressure, 13.6 mmHg at 37 degrees C), and Perflubron (PFB; vapor pressure, 10.4 mmHg at 37 degrees C) were used for PLV with no replacement for 4 h. A thermal detector was used to measure PFC loss rate. Physiological measurements and evaporative loss rate of PFC were done every 30 min, and lung histology was examined. RESULTS: The mean evaporative loss rate was significantly higher in the PP4 group (4.75 +/- 0.24 mL/kg per h) than in either the PFD (1.43 +/- 0.11 mL/kg per h) or the PFB (1.18 +/- 0.05 mL/kg per h) group (P < 0.05). The oxygenation of PFD and PFB was maintained good for 4 h, however, the PP4 group showed a fast deterioration since 2 h post-treatment due to fast dropping of the residual PP4 amount in lungs. Histology showed good alveolar integrity in the PFD and PFB groups. CONCLUSIONS: The effects of PLV are directly influenced by the evaporative property of the PFC liquid. With no replacement over 4 h, PLV effects could be maintained with utilizing a PFC liquid with low, rather than high, vapor pressure. PFC with high vapor pressure has a high loss rate and low residual volume that causes poor maintenance on oxygenation during PLV. Therefore, measuring PFC loss rate is important in future studies and clinical application of PLV.     

Conversion of proendothelin-1 into endothelin-1 by aspartylproteases

The ability of cathepsin D, chymosin, pepsin and renin to produce endothelin-1 (ET-1) from proendothelin-1 (proET-1) was compared. No significant conversion was observed when proET-1 was incubated with up to 1 U of renin for 15 min at 37°C. Cathepsin D generated, as well as degraded, ET-1 rapidly. Net production of ET-1 reached a maximum when 0.003 U of cathepsin D was used, and about 16% of the initial proET-1 was detected as ET-1 by HPLC. Pepsin up to 1 U converted pro ET-1 into ET-1 dose-dependently with a maximum of 71% conversion. A further increase of the amount of pepsin in the reaction mixture produced nonspecific cleavage of ET-1. Less than 10% of ET-1 remained in the presence of 15 U of pepsin. Chymosin also generated ET-1 dose-dependently, and a complete conversion was obtained at 1 U of enzyme. Greater than 1 U of chymosin only slightly degraded ET-1; at least 80% of ET-1 was still present when 15 U of chymosin was included in the assay. Other properties associated with the conversion of proET-1 into ET-1 by chymosin were investigated. Similar to authentic ET-1, the product of chymosin treatment caused contraction of isolated rabbit aortic rings, and pre-incubation of chymosin with pepstatin A abolished this contractile response. Using fast atom bombardment mass spectrometry, the molecular weights of the two peptide fragments generated from proET-1 by chymosin were shown to be identical to those of authentic ET-1 and the C-terminal fragment of proET-1. The optimal pH of the enzyme reaction was between 3.5 and 4.5, and the K_m and V_max values for the enzyme were 140 μM and 102 nmol/(mg min), respectively. These results indicate that chymosin specifically and rapidly converts proET-1 into ET-1 in vitro.     

Overt hypothyroidism with rhabdomyolysis and myopathy: a case report

Muscle involvement in adults with hypothyroidism is common. At least 79% of patients with hypothyroidism have muscle weakness, cramps, and myalgia complaints.1 The patients with hypothyroidism do have myopathy rather than functional muscle diseases.2 Nonspecific muscle stiffness related to myalgia may be associated with serum muscle enzyme elevations. Serum creatine kinase （CK） elevation can be observed in 57%-90% of patients with hypothyroidism. Skeletal muscle is affected more profoundly in cases of overt hypothyroidism,     

台东县原住民布农族小学健康体重行动研究

目的通过实行行动研究方法,从健康促进学校6大范畴介入,以改善学生身体质量指数(BMI)、体重控制行为及运动时间。方法使用问卷调查,以本校1~6年级学生为对象,先进行前测,然后进行介入,期间配合学校的体能活动与每天20min课间活动,进行健康操、跳绳和跑步等,并给予饮食营养教育。倡导(含家长)、督促饮用白开水每天2次,每天3蔬2果,共开展活动3个月,每天进行体重检测,每周进行身高检测,施行自我及饮食内容评估。结果通过6大范畴介入,学生BMI正常占比由58.9%提升至66.1%。总体而言学生正常BMI占比、运动的天数与时间有显著提升。结论经由学校推动全方位健康体重活动各项策略及定期测量身高、体重,有助于学生对体重的控制。     

Monthly recombinant tissue plasminogen activator administration to implantable central venous access devices decreases infections in children with haemophilia

Summary.  Central venous access devices (CVAD) have been effectively used in the care of haemophilia patients. This is particularly true in children, who often have difficult venous access. CVAD complications (infection and thrombosis), risk factors, and complication rates, have been well-documented. However, effective interventions which decrease complication rates have not been identified. In this study, we review our experience with the use of monthly recombinant tissue plasminogen activator (rtPA) administration in haemophilia patients with fully implanted CVADs. Data on 19 haemophilia patients with 24 CVADs were available for analysis, with a total of 24 520 CVAD days. An infection rate of 0.04 infections per 1000 CVAD days and a thrombosis rate of 0.04 thrombi per 1000 CVAD days was observed. The observed infectious complication rate is at least one logarithm lower than many published CVAD infection rates in haemophilia patients who have not received rtPA administration. No bleeding complications were noted. Monthly rtPA is safe and appears to be effective in decreasing CVAD infection rates. Larger, randomized controlled studies are indicated to validate this finding.     

Medical treatment of duodenal ulcer: Acid inhibition or Helicobacter pylori eradication?

To ascertain whether acid inhibition or Helicobacter pylori (HP) colonization is the decisive factor in the healing of duodenal ulcer, we treated 54 patients with famotidine and carried out long-term follow-up. Helicobacter pylori colonization was found in 70.4% of patients before treatment. There were no differences in the pre-treatment characteristics between patients with HP positive or HP negative ulcers. The 4-week and 8-week healing rates after famotidine treatment were 72.5% and 82.4% respectively. No difference in HP colonization was found between patients with ulcer healed and those with ulcer not healed (78.4% vs 64.3% at 4th week and 77.3% vs 71.4% at 8th week, P greater than 0.05). In patients with ulcer healed at 4th week, the intragastric pH was raised significantly and the antral acute inflammation was less severe than those with ulcer not healed. Ulcer recurrence was found in 76.9% of patients within 1 year, but there was no difference in ulcer recurrence between the patients with positive or negative HP colonization at the time of ulcer healing. Our results suggest that duodenal ulcer healing and recurrence are closely related to acid inhibition rather than to HP colonization.     

Serum procarboxypeptidase B, amylase and lipase in chronic renal failure

Procarboxypeptidase B (human pancreas-specific protein) has been reported to be a good serum marker for the diagnosis of acute pancreatitis. The current study was conducted in order to evaluate the frequency and degree of elevated serum levels of procarboxypeptidase B in chronic renal failure and their correlations with serum levels of amylase, lipase and renal function tests. Blood samples were taken from 84 asymptomatic patients with chronic renal failure, including 34 patients with periodical haemodialysis and 50 patients without haemodialysis. Serum levels of procarboxypeptidase B, amylase, lipase, creatinine and blood urea nitrogen were measured. Serum levels of procarboxypeptidase B in 84 patients were 63.4±5.5 μg/L significantly greater than the figure of 29.6±1.6 μg/L in healthy adults in our previous report (P< 0.0001). There was a significant difference in serum levels of PCPB between patients with and without haemodialysis (78.0±9.4 vs 53.6±6.3 μg/L; P< 0.01). The frequencies of elevated serum levels of procarboxypeptidase B, amylase and lipase greater than upper normal limits were 27.4, 35.7 and 26.2%, respectively. The frequencies of elevated PCPB in patients with and without haemodialysis were 38.2 and 20%, respectively. Only one patient had a serum procarboxypeptidase B level greater than three-fold the upper normal limit. A significant correlation was found between procarboxypeptidase B and lipase (r = 0.785; P< 0.0001). No significant correlation was noted between procarboxypeptidase B vs amylase or renal function tests. In conclusion, in patients with chronic renal failure, the elevation of serum procarboxypeptidase B is as common as the elevations of other pancreatic enzymes.     

台湾新竹市国中生摄取西式快餐行为及其相关因素研究

[目的]了解台湾新竹国中学生摄取西式快餐现况,进一步探讨背景因素、营养知识、饮食态度、拒绝摄取的自我效能与摄取行为间的关系。[方法]用问卷进行调查,以t检验、单因素方差、多元回归等进行分析。[结果]女生的营养知识、饮食态度平均得分高于男生;拒绝摄取西式快餐自我效能偏向容易;整体摄取西式快餐行为,以“每次西式快餐,一定吃完”、“在快餐店购买西式快餐”和“在路边摊购买西式快餐”最为普遍;近20%的国中生在过去1周内摄取西式快餐;男生比女生吃得较多;每周零用钱、西式快餐营养知识、饮食态度、拒绝摄取的自我效能对摄取行为的解释力为27.3%;每周零用钱、拒绝摄取的自我效能为摄取西式快餐行为之重要影响因素。[结论]教师应培养学生健康的饮食行为,勿过量摄取西式快餐。