康惠尔水胶体敷料在治疗长期卧床老年患者压疮方面的疗效观察与护理

目的：观察长期卧床的老年患者使用康惠尔水胶体敷料治疗压疮方面的疗效。方法收集我科近1年来共42例压疮,采用对照组与观察组的方法,对照组21例,观察组21例,均为长期卧床的老年患者,两组患者通过使用康惠尔水胶体敷料对压疮治疗的观察与护理,以9d为1个疗程,采用统计学分析。结果康惠尔水胶体敷料在治疗压疮方面有显著的疗效,同时便于患者的护理,值得推广使用。     

Regional distribution of action potential abnormalities induced by subacute right ventricular pressure overload

Right ventricular pressure overload of 3 days' duration was established in cats by banding of the pulmonary artery. To characterize the regional distribution of the resulting electrophysiologic changes, the right ventricular free wall, adjacent pulmonary outflow tract and septum were mounted in tissue bath and examined by conventional microelectrode techniques. Abnormal action potentials, identified by a negative shift of the voltage level of phase 2 with a corresponding accentuation of phase 1, were recorded from sites contiguous to the tricuspid valve and pulmonary outflow tract and in limited adjacent areas. No abnormal action potentials were recorded on the septal surface, apical end of the free wall, or at any right ventricular location in normal or sham-operated cats. Abnormal potentials could be recorded from sites sampled 5 cell layers deep in the endocardium. The number and extent of distribution of cells demonstrating altered action potentials correlated best with increased right ventricular wet weight at time of sacrifice. Abnormal cells responded to epinephrine or elevated extracellular calcium by a shift in plateau voltage towards zero and by an increase in action potential duration prior to usual plateau shortening. Responsiveness of these cells to agents which influence slow inward current suggests pressure overload-induced changes in the cell membrane that limit or otherwise affect availability of calcium. Regional distribution of plateau potential abnormalities may reflect differential physical stress within the myocardium provoked by sudden pressure overload.     

Intravenous Fluid Administration: Improving Patient Outcomes With Evidence-based Care

Intravenous (IV) fluid administration is one of the most common interventions in the hospital setting. The associated complication rate is higher than previously believed, with adverse effects impacting recovery, length of stay, cost, patient safety, and survival. Several patient populations are at increased risk, and there are substantial data implicating inappropriate fluid administration as a contributing factor to increased morbidity and mortality. Related complications are largely preventable, and unmet educational needs are well-documented. An increase in evidence-based management has the potential to improve outcomes related to a number of quality indicators.     

不同压力对巨噬细胞ATP结合盒转运子A1表达的影响

目的观察不同压力对巨噬细胞ABCA1 mRNA及蛋白表达的影响。方法将THP—1源巨噬细胞依照不同压力分为对照组、60组、80组、100组、120组、140组、160组和180组，分别在大气压下，60mmHg、80mmHg、100mmHg、120mmHg、140mmHg、160mmHg和180mmHg压力下继续培养48h。观察巨噬细胞ABCA1 mRNA及蛋白表达。结果60组、80组、100组、120组ABCA1 mRNA分别为1．11±0．08、1．31±0．04、1．53±0．11和1．15±0．07，较对照组（0．91±0．10）明显增加（P〈0．05或P〈0．01），以100组增加最显著；140组、160组和180组ABCA1mRNA分别为0．75±0．06，0．46±0．08及0．35±0．05，较对照组明显减少（P〈0．01）。ABCA1蛋白表达与mRNA情况相似：60组（1．09±0．06），80组（1．12±0．09），100组（1．41±0．06），120组（1．11±0．06）较对照组（1．00±0．00）明显增加（P〈0．05或P〈0．01），而140组（0．78±0．07）、160组（0．49±0．09）和180组（0．47±0．10）较对照组明显减少（P〈0．01）。结论压力在80---120mmHg范围时，压力升高促进了巨噬细胞ABCA1 mRNA及蛋白表达，压力〉120mmHg后，随着压力的增高，巨噬细胞ABCA1 mRNA及蛋白表达反而减少。     

Refractory Crow-Fukase Syndrome (POEMS Syndrome) Successfully Treated with High-Dose Melphalan followed by Autologous Peripheral Blood Stem Cell Transplantation

Crow-Fukase syndrome (CFS) is a multisystemic disorder. Because it is characterized by polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, sclerotic bone lesions, and skin changes it is also known as POEMS syndrome. Extravascular volume overload is also one of the main symptoms. Uncontrollable extravascular volume overload is one of the major causes of death and one of the negative prognostic factors. Control of the extravascular volume overload is an important therapeutic strategy for this syndrome. We report here a case of CFS with extravascular volume overload resulting in pleural effusion and massive edema in the lower extremities, which was refractory to oral administration of melphalan and prednisolone. The patient's condition correlated with the serum level of vascular endothelial growth factor and markedly improved after administration of high-dose melphalan (200 mg/m²) followed by autologous peripheral blood stem cell transplantation. This approach should be considered in patients with CFS who fail to respond to conventional chemotherapy and have uncontrollable extravascular volume overload.     

Effect of ventilation by high-frequency oscillation on lung and chest wall mechanics in the dog

High-frequency oscillation (HFO) has been shown to be effective in maintaining gas exchange, but the effects of high-frequency, small-volume ventilation on the mechanical properties of the respiratory system are unknown. A volume displacement plethysmograph was used to study lung volumes and static pressure-volume (PV) curves during HFO in pentobarbital-anesthetized dogs. During long-term studies, adequate gas exchange was maintained with a stroke volume of 2.5 ml/kg and frequencies between 15 and 30 Hz. The effect of 5–7 hours of HFO on lung and chest wall mechanics was studied in 8 dogs. In another 8 dogs the relationship of volume history and respiratory muscle tone to occlusion airway pressure and lung volume during short-term HFO was investigated. With prolonged HFO, a small but significant decrease in total lung capacity occurred by 5 hours and the static respiratory system PV curve shifted slightly to the right. These changes were reversed by muscle paralysis and may be explained by a change in respiratory muscle tone. Static lung compliance and the hysteresis ratio (an index of tissue properties) remained unchanged. The relationship of occlusion airway pressure and lung volume during short-term HFO was dependent on the lung volume history and was influenced by respiratory muscle tone only at low airway pressures. These findings suggest that during prolonged HFO a small increase in chest wall stiffness may result. However, occlusion airway pressure and lung volume at the onset of HFO are mainly dependent on the volume history of the lung. Presented in part at the Fall Meeting of the American Physiological Society, Toronto, Canada, October 12–17, 1980     

Mechanistic insights of the controlled release capacity of polar functional group in transdermal drug delivery system: the relationship of hydrogen bonding strength and controlled release capacity

BackgroundHydrogen bonding interaction was considered to play a critical role in controlling drug release from transdermal patch. However, the quantitative evaluation of hydrogen bonding strength between drug and polar functional group was rarely reported, and the relationship between hydrogen bonding strength and controlled release capacity of pressure sensitive adhesive (PSA) was not well understood. The present study shed light on this relationship.MethodsAcrylate PSAs with amide group were synthesized by a free radical-initiated solution polymerization. Six drugs, i.e., etodolac, ketoprofen, gemfibrozil, zolmitriptan, propranolol and lidocaine, were selected as model drugs. In vitro drug release and skin permeation experiments and in vivo pharmacokinetic experiment were performed. Partial correlation analysis, fourier-transform infrared spectroscopy and molecular simulation were conducted to provide molecular details of drug-PSA interactions. Mechanical test, rheology study, and modulated differential scanning calorimetry study were performed to scrutinize the free volume and molecular mobility of PSAs.ResultsRelease rate of all six drugs from amide PSAs decreased with the increase of amide group concentrations; however, only zolmitriptan and propranolol showed decreased skin permeation rate. It was found that drug release was controlled by amide group through hydrogen bonding, and controlled release extent was positively correlated with hydrogen bonding strength.ConclusionFrom these results, we concluded that drugs with strong hydrogen bond forming ability and high skin permeation were suitable to use amide PSAs to regulate their release rate from patch.     

Effect of Hepatic Isoferrttins from Iron Overloaded Rats on Lymphocyte Proldzerative Response: Role of Ferritin Iron Content

Abstract

Iron and ferritin impair a variety of immunological functions. To evaluate the effect of ferritin iron content on rat lymphocyte proliferative response, isoferritins that differ in their iron content and isoelectric point (pI) were isolated from iron overload rat livers by ultracentrifugation (isoferritins with high iron content and low pI) or crystallization (isoferritins with low iron content and high pI) methods. Additionally, commercial horse splenic ferritin (with a lower pI and higher iron content than rat isoferritins) was also tested. Proliferative response to Con A was decreased in a dose-dependent manner in all assays in which spleen cells were incubated with rat and horse isoferritins. However, isoferritins with higher iron contents (rat isoferritin obtained by ultracentrifugation and horse ferritin) caused a greater decrease of proliferative response at 5 and 25 μ/ml than the others. Rat and horse apoferritins showed no inhibitory effect on lymphocyte proliferative response, suggesting that the effect is due to iron probably through the damaging effect of reactive oxygen species generated by iron released by the isoferritins on lymphocyte functions.

Additionally, the role of serum ferritin level on proliferative response was studied in an experimental model of iron overload in rats. An inverse relationship between the proliferative response and serum ferritin levels was observed.

Our results suggest that the inhibitory effect of the isoferritins on lymphocyte proliferative response is due, at least partially, to the iron content of this protein and not exclusively to variation in pi as suggested by other authors. These results are in agreement with the possible immunosuppressor role of ferritin in vivo.     

The false premise in measuring body-support interface pressures for preventing serious pressure ulcers

Presently, commercial cushioning products for pressure ulcer prevention are being evaluated for their protective effect exclusively based on interfacial pressures between the cushion/mattress and the patient. However, interface pressures cannot predict elevated mechanical stresses in deep tissues adjacent to bony prominences. Such deep tissue stress concentrations are associated with local ischaemia and hypoxia, which over time result in deep tissue necrosis, particularly of muscle tissue. In order to demonstrate this phenomenon, a physical phantom of the mechanical interaction between the ischial tuberosities (IT) and gluteus muscles of the buttocks was built, incorporating geometric replica of the human IT and real (bovine) muscle tissue. Internal muscle stresses directly under the IT were five to 11-fold greater than stresses at more distal locations, and a Pearson correlation test showed that they could not have been predicted from the interface pressures in the phantom. Accordingly, though pressure ulcer prevention clinics which utilize routine sitting pressure measurements report effective outcomes, the present results highlight a problem in using body-support pressure measurements to predict the risk for pressure-related deep tissue injury.     

The effect of applied pressure on the electrical impedance of the bladder tissue using small and large probes

There are a number of studies using electrical impedance spectroscopy, a minimally invasive technique, as a tissue characterizing method with different probe sizes (usually with larger probe diameters than that used in this work). In urinary bladder studies the probe size are limited to 2 mm diameter, in order to pass through the working channel of the cystoscope to measure the impedance inside the urinary bladder. Thus, bio-impedance of the human urothelium can only be measured using a small sized probe for in vivo studies. Different pressures were applied with this probe and it was demonstrated that increasing the applied pressure over the probe would increase the measured electrical impedance of the bladder tissue. Therefore, the effect of applied pressure on the resulting electrical impedance was considered in this study (all of the measurements were taken on points that had benign histology). An excessive amount of the applied pressure beyond the first visible indentation (first recordable reading) pressure has a significant effect on the impedance of the bladder tissue (p < 0.001). Then, to reduce the effect of pressure on the measured bio-impedance, the effect of a larger probe (10 mm diameter) was considered (p < 0.001). Increasing the probe contact area is one way to reduce the pressure effect on measurements; however this is difficult in practice in the in vivo situation.