Further studies on interactions between periaqueductal gray, nucleus accumbens and habenula in antinociception.

Previous findings from this laboratory with the intracerebral microinjection technique suggested that the periaqueductal gray (PAG), nucleus accumbens, and habenula might constitute a unidirectional loop to play their roles in pain modulation. In the present study we demonstrate that intra-habenular injection of naloxone antagonizes the analgesia elicited by morphine injected into the periaqueductal gray (PAG) and that intra-accumbens injection of naloxone is capable of attenuating the analgesic effects of morphine injected into the habenula. These results indicate that the relationships between these nuclei may be more complex than the putative unidirectional loop.     

Transdermal permeation-enhancing activities of some inorganic anions

Effects of sodium salts of various monovalent inorganic anions on transdermal permeation of salicylic acid were investigated. In in-vitro experiment using a Franz-type diffusion cell and excised mouse skin, the permeation-enhancing activities of the sodium salts of inorganic anions were roughly proportional to lyotropic Hofmeister swelling abilities of the anions; F^?<SO₄ ^2?<Cl^? <ClO₄ ^?<NO₃ <SCN^? <Br <I^?, i.e. l, Br and SCN increased the flux of drugs through the mouse skin, while F^?, SO₄ ^2?, Cl^?, ClO₄ ^? and NO₃ ^? decreased or did not affect the flux. In invivo experiment using the rabbit as the test animal, the plasma concentration of salicylic acid of the rabbit to which 10%-salicylic acid ointment containing 5%-Nal or NaBr was applied was significantly higher than that of the rabbit to which the ointment without the electrolytes was applied. The amounts of sterol leached out of stratum corneum sheet when the sheet was immersed in aqueous solutions of Nal, NaBr, or NaSCN were much more than that of stratum corneum immersed in aqueous solutions of the other inorganic anions. The FTIR/ATR spectroscopy showed that the peaks at 2853 cm^?1 and 2924 cm^?1 in the IR absorption spectrum of the stratum corneum sheet of the mouse were shifted to higher frequencies by the anions which enhanced the transdermal drug permeation, while not shifted by the anions which did not have any permeation-enhancing activities or have permeation-reducing activities. These results suggest that sodium salts of some anions such as iodide, bromide and thiocyanate enhance transdermal permeation of salicylic acid through swelling and perturbation of the skin structure by these anions.     

Disability and depression: investigating a complex relation using physical performance measures.

OBJECTIVE: The objective of this study was to examine the relation of physical performance measures with depressive symptoms in older men. METHOD: A cross-sectional, multivariate comparison of several measures of upper- and lower-extremity performance and their relation with depressive symptoms was performed in 2,856 older Japanese American men, aged 71-93 years, who participated in the fourth examination of the Honolulu Heart Program. Depressive symptoms were measured using an 11-item version of Center for Epidemiologic Studies Depression (CES-D) Scale. A score of at least 9 (from a maximum score of 33) is considered clinically significant. Timed functional performance tests, including walking and repeated chair stands, were used to assess lower-extremity performance; handgrip strength was used as an indicator of upper-extremity performance. RESULTS: Two hundred eighty-three participants (9.9%) had a score of 9 or greater on the 11-question CES-D Scale and were considered to be at high risk for depression. Time to walk 10 feet and time to complete five chair stands were significantly longer in those with depressive symptoms, whereas handgrip strength was significantly lower. Only the association of gait speed (time to walk 10 feet) and depressive symptoms remained significant when all physical performance measures were simultaneously included in a multivariate analysis. CONCLUSION: These results demonstrate physical performance measures, particularly gait speed, may be important potential correlates of depression in community-dwelling older men.     

Panfacial fractures: analysis of 33 cases treated late.

PURPOSE: The aim of this retrospective study was to analyze the characteristics of delayed panfacial fractures and evaluate treatment results. PATIENTS AND METHODS: Thirty-three patients with delayed panfacial fractures were treated in the Maxillofacial Trauma Center of Peking University, School and Hospital of Stomatology between 1998 and 2004. Each patient was examined by computed tomography (CT) scans before operation. For those who had no severe opening restriction, dental impressions were taken to fabricate dental casts. For those with severely comminuted fractures, 3-dimensional (3D) models of the facial skeleton were used. Re-establishing the continuity of the mandible was the first step and then used as a platform to reconstruct the maxillary fractures via maxillomandibular fixation after Le Fort I osteotomy. The third step was to restore the mid- and upper-facial width and projection by coronal approach to expose the zygomatic complex and frontal bone/sinus and/or naso-orbito-ethmoid (NOE) fractures. RESULTS: There were 3 types of mandibular fractures that affected the treatment plan: 1) type I, mandibular body/symphysis fracture(s) (17/33, 51.52%); 2) type II, mandibular angle and/or condylar fracture(s) (6/33, 18.18%); and 3) type III, both mandibular body/symphysis and angle/condylar fractures (10/33, 30.30%). Fourteen cases were associated with NOE fractures (42.42%) and 3 cases had frontal sinus fractures (9.1%). Twelve cases had enophthalmos (36.36%) and 3 lost 1 eyeball. The order of treatment was dependent on the mandibular fracture type. For type I fractures, reconstructing the mandibular arch was the first step. For type II fractures, repairing the angle, ascending rami, and condylar areas was the first step. For type III fractures, when both mandibular height and arch were disrupted, freeing the malunited angle or condyle was the first step before restoring the mandibular arch form. Reconstruction of the mandibular height and projection was then carried out. For all 3 types, the second step was to restore the mid- and upper facial width and projection by reducing the zygomatic complex and frontal bone/sinus or NOE fractures. Maxillary fixation across the Le Fort I level was the last step. Le Fort I osteotomy was used for all 33 cases. Bone grafts and soft tissue suspension also were used. Twenty-one cases (63.64%) had good results, 7 (21.21%) cases were acceptable, and 5 (15.15%) were not good. There were 7 cases (21.21%) that still had soft tissue problems that needed secondary operations. CONCLUSIONS: Reconstruction of the mandible first with Le Fort I osteotomy is a good way to treat delayed panfacial fractures. Computed tomography and 3D CT, model surgery, and occasionally 3D models are necessary aids for diagnosis and treatment. Soft tissue problems, including lacerations and asymmetries, were often the factors that caused an unfavorable outcome.     

质疑Frank—Starling心脏定律

心脏收缩释放的能量（作功）是心肌纤维长度（心室舒张末期容积，EDV）的函数，即Frank—Star一1ing（FS）心脏作功定律，被誉为心脏生理学中的“经典”理论。对此，笔者从各种不同角度进行了探讨：首先分析了Frank伸展离体心肌和Starling及其同事使用心肺制备做的实验与动物生理实际的差异，以及人们在实验中观测到的增加心肌前负荷引起收缩力增强的现象（FS现象），认为：①在正常生理条件下的动物体内，来自心脏以外的、如同心肺制备中那样人工控制心室充盈压力升高、引起EDV增加的那种血液的重力动力是不存在的。②另一方面，人为地增加前负荷，那是改变了心肌收缩时的外环境条件。③由此而激发出的FS现象，是心脏适应其外环境条件变化所作出的反应。④此种心肌收缩力增强的反应，需通过心肌细胞内部与收缩过程发生有关的心肌兴奋一收缩和化学一力学偶联等一系列生化机制（不恒定因素）方能得以实现。⑤根据他们实验中观测到的FS现象，在逻辑上不能得出前负荷这一心肌收缩时的外环境条件变化调控其作功的推论。换言之，所有的在实验中被激发出来的FS现象，都不足以成为支持FS心脏定律的证据。然后，引用国内外公认的计算心脏每搏射血作功（w）的生物物理学公式“w=P×（EDV—ESV）”，证明了w和EDV之间没有函数关系。根据心脏作功的医用物理学和生物数学的基本原理，笔者认为Frank—Starling心脏定律表达的不是心脏作功的规律。     

Pyruvate-modified perfadex improves lung function after long-term hypothermic storage.

BACKGROUND: Lungs harvested for transplantation are stored while inflated with oxygen, which can serve to support oxidative metabolism. However, strategies aimed at increasing graft metabolism during storage have received little attention. In this study, we added pyruvate to the preservation solution Perfadex and measured the effects on oxidative metabolism and reperfusion lung function. METHODS: Rat lungs were stored for 6 and 24 hours in low-potassium dextran solution at 10 degrees C containing either 5 mmol/liter uniformly carbon-13 (U-(13)C) labeled glucose (Perfadex), 32 mmol/liter 3-(13)C pyruvate (pyruvate), or both (combined). Oxidation of exogenous substrates was measured as the incorporation of (13)C into tricarboxylic acid cycle intermediates by magnetic resonance spectroscopy. Additional groups of lungs with each substrate modification were preserved for 6 or 24 hours and then reperfused. RESULTS: Enrichment of tricarboxylic acid cycle intermediates was low in the Perfadex group (9% at 6 hours and 32% at 24 hours of storage, respectively). In contrast, enrichment was significantly increased in both the pyruvate group (50% and 59%, respectively) and combined group (39% and 54%, respectively) compared with the Perfadex group (p<0.01). Graft function was excellent after 6-hour storage in all groups. All lungs stored for 24 hours exhibited inferior lung function, but oxygenation, pulmonary artery pressures, and airway pressures in the combined group were significantly improved compared with the Perfadex group (p<0.05). CONCLUSIONS: Preservation solution substrate composition influences graft metabolism during storage. The addition of pyruvate to Perfadex increases metabolism during storage and improves reperfusion lung function.