SAA-only HDL formed during the acute phase response in apoA-I+/+ and apoA-I-/- mice

Serum amyloid A (SAA) is an acute phase protein of unknown function that is involved in systemic amyloidosis and may also be involved in atherogenesis. The precise role of SAA in these processes has not been established. SAA circulates in plasma bound to high density lipoprotein-3 (HDL3). The pathway for the production of SAA-containing HDL is not known. To test whether apolipoprotein (apo)A-I-HDL is required in the production of SAA-HDL, we analyzed the lipopolysaccharide (LPS)-induced changes in apoA-I+/+ and apoA-I-/- mice. In apoA-I+/+ mice, after injection of LPS, remodeling of HDL occurred: total cholesterol increased and apoA-I decreased slightly and shifted to lighter density. Dense (density of HDL3) but large (size of HDL2 ) SAA-containing particles were formed. Upon fast phase liquid chromatography fractionation of plasma, >90% of SAA eluted with HDL that was enriched in cholesterol and phospholipid and shifted "leftward" to larger particles. Non-denaturing immunoprecipitation with anti-mouse apoA-I precipitated all of the apoA-I but not all of the SAA, confirming the presence of SAA-HDL devoid of apoA-I. In the apoA-I-/- mice, which normally have very low plasma lipid levels, LPS injection resulted in significantly increased total and HDL cholesterol. Greater than 90% of the SAA was lipid associated and was found on dense but large, spherical HDL particles essentially devoid of other apolipoproteins.We conclude that serum amyloid A (SAA) is able to sequester lipid, forming dense but large HDL particles with or without apoA-I or other apolipoproteins. The capacity to isolate lipoprotein particles containing SAA as the predominant or only apolipoprotein provides an important system to further explore the biological function of SAA.

[Biological characteristics and damaging regularities of grubs endangering the growth of Ophiopogen japonicus (Thunb.) Ker-Gawl]

OBJECTIVE

To provide a scientific basis for prevention and control of the damage done to Ophiopogen japonicus by grubs.

METHOD

Conducting laboratory observation along with field investigation.

RESULT

The grubs endangering the growth of O. japonicus are mainly Hoplosternus incanus, Holotrichina paraullela and Anomala corpulenta, H. incanus takes two years to make a generation and overwinters in the form of second or third-instar larvae. H. parallela and A. corpulenta generate yearly and overwinter in the form of third-instar larvae. The extent of the damage done to O. japonicus by grubs is related to such factors as the number of sequential cropping years, the model of intercropping and the type of soil.

CONCLUSION

Prevention and control of the pest grub should be based primarily on proper agricultural (cultivating) measures.

[Clinical application of 2 mm micro-thoracoscopic surgery]

OBJECTIVE

To determine the clinical safety and efficacy of micro-thoracoscopic surgery.

METHOD

From July 1996 to July 1997, video-assisted thoracoscopic surgery was performed in 47 patients by using 2 mm microthoracoscope. There were 36 males and 11 females. Their age ranged from 40 to 75 years with a mean age of 56.7 years. Surgical procedures included bullectomy (16 patients), wedge resection (3), lung cancer staging (4), lobectomy (2), exploration (15), and resection of mediastinal tumor (2), esophagectomy (1) and repair of pneumothorax (4). Local anesthesia was employed in 18 patients and general anesthesia with double lumen endotracheal tube in 29.

RESULT

There were no operative mortality and postoperative complications.

CONCLUSION

2 mm micro-thoracoscopic surgery could be used in the management of a variety of thoracic conditions. It may be of significant value for diagnostic and therapeutic purposes, but the further study for this new technique is required to determine its safety and efficacy.

[Thoracoscopic lung reduction surgery for emphysema]

OBJECTIVE

To study the surgical treatment of emphysema.

METHOD

Five patients with severe diffused pulmonary emphysema underwent surgical bilateral lung volume reduction by video-assisted thoracoscopy. All patients were male and their age ranged from 60 to 71 years (mean 64.3 years). Before surgery, 5 patients required supplement oxygen with exertion and one oxygen supplement at rest. Preoperative and postoperative assessments included standard pulmonary function studies, chest CT scan and quantitative nuclear lung perfusion and ventilation scan. Wedge resection was performed were in 3 patients, simple plication in 1, and combined wedge resection and plication in 1. There were no early or late mortality and no requirement for immediate postoperative ventilatory assistance.

RESULT

Follow-up ranged from 10 to 12 months. After surgery the mean forced expiratory volume in 1 second (FEV(1)) was significantly increased from 0.46 L to 1.13 L (P < 0.001) and the mean forced vital capacity (FVC) was markedly improved from 1.74 L to 2.93 L (P < 0.001). Pulmonary compliance was significantly improved and resistance of airway decreased (P < 0.001). The mean distance during 6-min walk test increased from 10 m to 400 m in 4 patients.

CONCLUSION

Thoracoscopic bilateral lung volume reduction is an effective and safe technique for patients with severe emphysema. It can relieve dyspnea and improve in excise tolerance and quality of life.

Effects of biliary tract pressure on dynamics of the Oddi's sphincter and its nerve mechanism

In order to explore the effect of biliary tract pressure on Oddi's sphincter and the mechanism of development of high pressure of biliary tract during acute obstructive and suppurative cholangitis (AOSC), house rabbits were used to establish model of high biliary pressure in acute biliary duct caecus. It was observed that when the pressure of the acute biliary tract was increased to 8 kPa, the electric activity of Oddi's sphincter was obviously enhanced, the pressure of Oddioes sphincter increased remarkably (P < 0.05), and even constant spasm appeared with accompanying increase of discharge frequency of the right greater splanchnic nerves (P < 0.05) and progressive decrease of mean arterial pressure. However, when lidocaine of 0.6% was used to block the right celiac plexus, no above-mentioned reaction happened when the biliary tract pressure was increased again. The results indicated that the acute biliary tract obstruction might induce the contraction or spasm of Oddi's sphincter and bring about a vicious cycle. Its mechanism is related to splanchnic nerves reflection and it is one of important factors in the development of AOSC course.

[A study on three dimensional modeling of human body in man-machine system simulation]

Modeling of the human body is a basic problem in human-machine system simulation. In this study a B-spline surface model of the human body was established. In the modeling, human body is split into several segments and each segment is a cubic B-spline surface. A blend surface was used to link two jointed segments. It is easy to simulate the motion of the human body by using the algorithm of axial deformation.

The RNA molecule CsrB binds to the global regulatory protein CsrA and antagonizes its activity in Escherichia coli

The RNA-binding protein CsrA (carbon storage regulator) is a new kind of global regulator, which facilitates specific mRNA decay. A recombinant CsrA protein containing a metal-binding affinity tag (CsrA-H6) was purified to homogeneity and authenticated by N-terminal sequencing, matrix-assisted laser desorption/ionization time of flight mass spectrometry, and other studies. This protein was entirely contained within a globular complex of approximately 18 CsrA-H6 subunits and a single approximately 350-nucleotide RNA, CsrB. cDNA cloning and nucleotide sequencing revealed that the csrB gene is located downstream from syd in the 64-min region of the Escherichia coli K-12 genome and contains no open reading frames. The purified CsrA-CsrB ribonucleoprotein complex was active in regulating glg (glycogen biosynthesis) gene expression in vitro, as was the RNA-free form of the CsrA protein. Overexpression of csrB enhanced glycogen accumulation in E. coli, a stationary phase process that is repressed by CsrA. Thus, CsrB RNA is a second component of the Csr system, which binds to CsrA and antagonizes its effects on gene expression. A model for regulatory interactions in Csr is presented, which also explains previous observations on the homologous system in Erwinia carotovora. A highly repeated nucleotide sequence located within predicted stem-loops and other single-stranded regions of CsrB, CAGGA(U/A/C)G, is a plausible CsrA-binding element.

[Clinical application of a modified small posterolateral thoracotomy in general thoracic surgery]

To assess the application of a modified thoracotomy approach in general thoracic operation. 311 general thoracic operations were performed using a modified small posterolateral thoracotomy surgical procedures included lobectomy plus lymph nodes dissection in 186, pneumonectomy in 23, esophagectomy for esophageal cancer in 23. The modified method of thoracotomy had following advantages: (1) reduce postoperative morbidity; (2) reduce bleeding and bank blood transfusion; (3) shorter operating time. This study suggested that the modified small posterolateral thoracotomy have some advantages than standard approach. It should be used in some selected thoracic operations.

[Detection of nicotine in prehistorical skeletal remains of South China]

Human remains from excavation sites in southern China, dated from 100 to 10,000 years, were investigated for nicotine. The nicotine concentrations were measured by radioimmunoassay. Consequently, the values measured represent the sum of nicotine and its metabolites. Positive results were observed in 25.9% (mean values of all samples). The concentrations ranged from 11.8 to 474.2 ng/g sample. From the excavation sites with the highest number of individuals, Chongtong (18 individuals) were 38.9%, and from the site Leigund (21 individuals) were 28.6% from the samples nicotine positive. The highest level with 474.2 ng/g nicotine was found in a sample dated 100 years. It is possible, that this individual was smoker. In addition the samples were investigated also by gas chromatography/mass spectrometry. The GC/MS indicated the presence of nicotine and its primary metabolite, cotinine. The presence of cotinine points out the assumption that nicotine was used antemortem. The detection of unchanged nicotine indicates that nicotine remained present in bones up centuries.

[230 cases of video-assisted thoracoscopic surgery]

We performed video-assisted thoracoscopic surgery (VATS) in 230 cases. As traditional technique is used in VATS, the operetive cost is lower, and more and more patients may accept VATS.

Microcomputer system for automatic identification of the Cryptococcus neoformans and its clinical application

In this study, microcomputer image processing and pattern recognition technology, and the knowledge of morphology and optical characteristics of Cryptococcus neoformans were used for identification of Cryptococcus neoformans. Four groups of mice were lethally infected with standard strain, Wuhan strain, American B-2643 strain and Var. Shanghainesis of the Cryptococcus neoformans. The samples collected included mice brain, lung, kidney, liver, small intestine tissue and were observed under a light microscope. More than 600 images of the fungus were input into a microcomputer. A system of computer for automatic identification of the Cryptococcus neoformans was developed. The technique involved image preprocessing, image segmenting, coding of line-length on the edge, curve fitting, extracting of image feature, building of image library and feature data bank etc.. And then, 768 images of the clinical samples and other fungus samples whose morphological features tend to be confused with Cryptococcus neoformans were input into microcomputer and subjected to automatic identification. The Cryptococcus neoformans was accurately identified within 15 min, and the consistency rate with results of routine culture was 98%.

Modelling and Analysis of Pulse Electrochemical Machining (PECM)

A small interelectrode gap in Electrochemical Machining (ECM) results in improved dimensional accuracy control and simplified tool design. However, using a small gap with conventional ECM equipment adversely affects the electrolyte flow or mass transport conditions in the gap, leading to process instability. The most remarkable breakthrough in this regard is the development of ECM using pulsed current. Pulse Electrochemical Machining (PECM) involves the application of a voltage pulse at high current density in the anodic dissolution process. PECM allows for more precise monitoring and control of machining parameters than ECM using continuous current. Small interelectrode gap, low electrolyte flow rate, gap state recovery during the pulse-off times and improved anodic dissolution efficiency features encountered in PECM lead to improved workpiece precision and surface finish when compared with ECM using continuous current. This paper presents mathematical models for the PECM process which take into consideration the nonsteady physical phenomena in the gap between the electrodes, including the conjugate fields of electrolyte flow velocities, pressure, temperature, gas concentrations, current densities and anodic material removal rates. The principles underlying higher dimensional accuracy and simpler tool design attainable with optimum pulse parameters are also discussed. Experimental studies indicate the validity of the proposed PECM models.

[Compatibility of Chinese drugs radix Aconiti carmichaeli with rhizoma Pinelliae]

To find out whether the Chinese drug Radix Aconiti Carmichaeli is compatible with another Chinese drug Rhizoma Pinelliae in preparation, the two medicinal herbs were made into different forms of decoctions. Experiments with these decoctions were carried out to observe the action on isolated hearts of toads and the ECG and acute toxicity on mice. The results showed that in terms of toxicity there was no marked increase in the mixed decoction as compared with the other two decoctions prepared from Radix Aconiti Carmichaeli and Rhizoma Pinelliae separately.