A Telemedicine Management Model Based on Message-Trigger Service

A telemedicine system model, based on a message-trigger service, is described. This model distributes system applications on multiple computers and establishes a communication platform to exchange messages among all applications. By broadcasting event messages, an application is able to trigger a set of local and remote services. At the same time, a protocol for message exchange is proposed to fulfill cooperation of applications. To validate the model, a teleconsultation system is designed. The results indicate that the model has good compatibility and that the characteristics are easy to implement.

[Efficacy of 40-O-(2-hydroxyethyl)-rapamycin in preventing chronic renal allograft rejection in rats]

OBJECTIVE

To study the efficacy of 40-O-(2-hydroxyethyl)-rapamycin (SDZ RAD) in preventing chronic renal allograft rejention in rats.

METHODS

The rat model of chronic renal allograft rejection was made with micro-surgery. The recipients were divided into two groups. The recipients in the study group were treated with SDZ RAD at a dose of 0.5 mg x kg(-1) x d(-1) by means of gavage and the controls with vehicle.

RESULTS

After 24 weeks of treatment, proteinuria, glomerular sclerosis, vascular intimal thickening and the infiltration of monocytesmacrophages and lymphocytes in the study group were decreased, in consistence with the reduced expression of ICAM-1, VCAM-1, TGF-beta(1) and PDGF-AA mRNA.

CONCLUSION

It is suggested that SDZ RAD can prevent chronic renal allograft rejection and the reduced expression of above adhesion molecules and growth factors may be involved in the mechanism.

[The influence of interferon alpha neutralizing antibodies on the therapeutic effectiveness in patients with chronic viral hepatitis]

OBJECTIVE

To study the influence of interferon alpha (IFN-alpha) neutralizing antibody (NA) on the therapeutic effectiveness of IFN-alpha.

METHODS

30 healthy persons and 116 patients with chronic viral hepatitis treated with IFN-alpha were studied, and the NA in their sera were tested by using the antiviral neutralizing bioassay (ANB).

RESULTS

None was positive for NA in sera of the healthy persons and patients before IFN-alpha treatment, 20 of 116 patients developed NA after IFN-alpha therapy, the positivity was 17.2% (20/116). NA appeared after 2 months of alpha IFN treatment, all 20 patients were positive after 6 months. The NA positivity in treated groups of IFN-alpha 2a, IFN-alpha 2b and IFN-alpha 1b were 34.6%, 13.2% and 11.5% respectively. The clearance rates of virus in NA-positive group and NA high-titered group were significantly lower than those in NA-negative group and NA low-titered group (P < 0.01 and P < 0.05, respectively) In contrast, the relapse rates of virus in NA-positive group was markedly higher than that in NA-negative group (P < 0.05).

CONCLUSION

NA may develop with its regularity in the chronic viral hepatitis patients treated with alpha IFN. The frequencies of NA development are related with the subtypes of alpha IFN used. NA can inhibit IFN activity, thereby affecting the therapeutic effectiveness of IFN.

Kinetics of synaptotagmin responses to Ca2+ and assembly with the core SNARE complex onto membranes

The synaptic vesicle protein synaptotagmin I binds Ca2+ and is required for efficient neurotransmitter release. Here, we measure the response time of the C2 domains of synaptotagmin to determine whether synaptotagmin is fast enough to function as a Ca2+ sensor for rapid exocytosis. We report that synaptotagmin is "tuned" to sense Ca2+ concentrations that trigger neuronal exocytosis. The speed of response is unique to synaptotagmin I and readily satisfies the kinetic constraints of synaptic vesicle membrane fusion. We further demonstrate that Ca2+ triggers penetration of synaptotagmin into membranes and simultaneously drives assembly of synaptotagmin onto the base of the ternary SNARE (soluble N-ethylmaleimide-sensitive fusion protein [NSF] attachment receptor) complex, near the transmembrane anchor of syntaxin. These data support a molecular model in which synaptotagmin triggers exocytosis through its interactions with membranes and the SNARE complex.

Overexpression of catalase in cytosolic or mitochondrial compartment protects HepG2 cells against oxidative injury

HepG2 cells were transfected with vectors containing human catalase cDNA and catalase cDNA with a mitochondrial leader sequence to allow comparison of the effectiveness of catalase overexpressed in the cytosolic or mitochondrial compartments to protect against oxidant-induced injury. Overexpression of catalase in cytosol and in mitochondria was confirmed by Western blot, and activity measurement and stable cell lines were established. The intracellular level of H(2)O(2) induced by exogenously added H(2)O(2) or antimycin A was lower in C33 cell lines overexpressing catalase in the cytosol and mC5 cell lines overexpressing catalase in the mitochondria as compared with Hp cell lines transfected with empty vector. Cell death caused by H(2)O(2), antimycin A, and menadione was considerably suppressed in both the mC5 and C33 cell lines. C33 and mC5 cells were also more resistant to apoptosis induced by H(2)O(2) and to the loss of mitochondrial membrane potential induced by H(2)O(2) and antimycin A. In view of the comparable protection by catalase overexpressed in the cytosol versus the mitochondria, catalase produced in both cellular compartments might act as a sink to decompose H(2)O(2) and move diffusable H(2)O(2) down its concentration gradient. The present study suggests that catalase in cytosol and catalase in mitochondria are capable of protecting HepG2 cells against cytotoxicity or apoptosis induced by oxidative stress.

A pacemaker working status telemonitoring algorithm

To extend the application of a previously developed home ECG and blood pressure telemonitoring system for pacemaker users, a specially designed pacemaker working status analysis algorithm is developed in this paper. This paper includes four sections. First, a pacing beat and spontaneous beat recognition algorithm are established in which a FIR filter and three threshold methods are used to pick up the pacing spikes and a dynamic threshold modification method is proposed for error elimination. Second, a beat classification algorithm is developed based on decision rules for six commonly used pacemaker types. Third, a pacemaker malfunction recognition algorithm is established to evaluate the pacemaker working status. Fourth, the statistics of the analysis and the report are also provided. To validate the algorithm, clinical data were collected and manually classified by specialists. Then, the classification and recognition results were obtained with the clinical data. Results show that the algorithm can achieve a recognition rate of 98.4%. Results also indicate that the algorithm is capable of working in real-time speed. The algorithm has been incorporated into the telemonitoring system, and trial application cases are also reported.

[Relationship between bone mineral density and blood and urine biochemical indices in women]

OBJECTIVE

To study the relationship between bone mineral density (BMD) and some biochemical indices in their blood and urine of women.

METHODS

Fasting urinary calcium (Ca) and creatinine (Cr), ratio of Ca to Cr, urinary hydroxyproline (Hyp), ratio of Hypr to Cr were determined in 163 healthy women, and activity of serum alkaline phosphatase (AKP) were determined in 182 healthy women. BMD at the 1/10 lower end and 1/3 middle-lower site of the radius were measured with single photon absorptiometry for all of them.

RESULTS

Serum AKP and ratio of urinary Hyp/Cr increased with age, especially postmenopause, and correlated negatively with BMD. Fasting urinary Ca/Cr ratio also increased with age, especially postmanopause, but not correlated with BMD.

CONCLUSION

Serum AKP and fasting urine Hyp/Cr ratio could be used as indicators to reflect bone remodeling and absorption, respectively.

[A digital simulation study on the effect of change in cardiovascular system parameters on the pulse waveform of the radial artery]

OBJECTIVE

To understand the effect of the change in cardiovascular system parameters on the pressure pulse waveform of the radial artery.

METHOD

A previously developed cardiovascular system mathematical model was used in this simulation study. The parameters used were heart rate, ventricular contractility, arterial compliance, peripheral resistance and blood viscosity.

RESULT

The change in each parameter would influence the pulse waveform. Most of the influences were in agreement with the results of clinical observations reported in the literature. However, several new phenomena were observed. The effect of change in single parameter on the pulse waveform was different for different combinations of other parameter values.

CONCLUSION

It is suggested that the model is useful in studying the relationship between cardiovascular system parameters and pulse waveform of the radial artery.

Specificity of notification for tuberculosis among screened refugees in NSW

OBJECTIVE

Epidemiological surveillance of tuberculosis (TB) in Australia is dependent on the accuracy of the notification data. We have investigated the specificity of TB notification for the diagnosis of this disease.

METHOD

We used data from notifications to the NSW Department of Health to identify members of a cohort of refugees who were screened between 1984 and 1993 and subsequently developed TB during that period. We reviewed notification data and, in most instances, case notes and x-ray films, to independently confirm or refute the diagnosis of TB.

RESULTS

Two hundred and fifty members of the cohort were identified in the notification database. After excluding refugees on treatment prior to arrival in Australia, and those who were notified as 'quiescent' and 'atypical' cases, there were 189 cases notified as active TB. There was evidence to support the diagnosis of active TB in 125 cases (66%) and evidence that subjects did not have active disease in 60 cases (32%). We could not determine the status of the remaining four notified cases.

CONCLUSION

This study has shown that, in a population of refugees subject to screening, nearly one-third of cases notified as active tuberculosis from the study population were actually not active tuberculosis cases.

IMPLICATIONS

The use of the TB notification database may result in overestimation of the incidence of TB in population groups who are subject to active screening.

[Development of the automatic dental X-ray film processor]

This paper introduces a multiple-point detecting technique of the density of dental X-ray films. With the infrared ray multiple-point detecting technique, a single-chip microcomputer control system is used to analyze the effectiveness of the film-developing in real time in order to achieve a good image. Based on the new technology, We designed the intelligent automatic dental X-ray film processing.

Estimation of quasi-straightforward propagating light in tissues

We have developed a controlled Monte Carlo (CMC) method to calculate the time-dependent transmittance of light through a thick tissue, especially for evaluation of the contribution from early arriving photons. Quasi-straightforward propagating trajectories are favoured according to a selection mechanism, so adequate trajectories of interest can reach the detector, improving the statistics dramatically. Simulations were conducted for tissue models with a thickness of 3-5 cm, and with optical properties similar to human breast tissue. Temporal profiles of early transmittance were obtained with satisfactory convergence. In addition, comparison was made with the conventional Monte Carlo approach to verify our scheme when applied to cases of optically thin tissues.

Sequence comparison of JSRV with endogenous proviruses: envelope genotypes and a novel ORF with similarity to a G-protein-coupled receptor

Ovine pulmonary carcinoma, a contagious lung cancer of sheep, is caused by the oncogenic jaagsiekte sheep retrovirus (JSRV) that is closely related to a family of endogenous sheep retroviral sequences (ESRVs). By using exogenous virus-specific U3 oligonucleotide primers, the entire JSRV proviral genome or its 3' part was amplified from tumor DNA. Analysis of these proviral sequences revealed a novel open reading frame (ORF) within the pol coding region, designated ORF X, which was well conserved in ESRV and JSRV sequences. Deduced amino acids of ORF X showed similarity to a portion of the mammalian adenosine receptor subtype 3, a member of the G-protein-coupled receptor family. Comparison of deduced env amino acids of six JSRV strains from three continents identified 15 residues that defined two distinct genotypes of JSRVs. Sequence analysis identified two highly variable regions between JSRV and ESRV in the transmembrane domain of env (TM) and the 3' unique sequence (U3) of the long terminal repeat, from which JSRV-specific DNA probes were derived. By using these DNA probes in Southern hybridization, for the first time we successfully identified JSRV proviral sequences in tumor genomic DNA in the presence of multiple ESRV loci, validating the use of exogenous virus-specific DNA probes in the analysis of oncogenic proviral integration sites and identification of integrated exogenous proviral sequences.

First trial of home ECG and blood pressure telemonitoring system in Macau

OBJECTIVE

To determine the feasibility of home monitoring of patients with cardiac disease or hypertension.

METHODS

An improved home electrocardiographic and blood pressure telemonitoring system linked to a central workstation was tested in 10 patients in Macau for 3 months.

RESULTS

The total number of connections was 1377. Of the automatic alarm connections, 32.5% were false positive, with the percentage of false positives ranging from 7.6 to 54.6 for different patients. Both patients and physicians found the system easy to use.

CONCLUSIONS

Further investigation is required to match the number of patients with the system capacity. A more robust dysrhythmia detection algorithm is needed to reduce the number of false alarms. Nevertheless, the results were sufficiently good that the trial is being expanded.

Detecting patterns of protein distribution and gene expression in silico

Most biological information is contained within gene and genome sequences. However, current methods for analyzing these data are limited primarily to the prediction of coding regions and identification of sequence similarities. We have developed a computer algorithm, CoSMoS (for context sensitive motif searches), which adds context sensitivity to sequence motif searches. CoSMoS was challenged to identify genes encoding peroxisome-associated and oleate-induced genes in the yeast Saccharomyces cerevisiae. Specifically, we searched for genes capable of encoding proteins with a type 1 or type 2 peroxisomal targeting signal and for genes containing the oleate-response element, a cis-acting element common to fatty acid-regulated genes. CoSMoS successfully identified 7 of 8 known PTS-containing peroxisomal proteins and 13 of 14 known oleate-regulated genes. More importantly, CoSMoS identified an additional 18 candidate peroxisomal proteins and 300 candidate oleate-regulated genes. Preliminary localization studies suggest that these include at least 10 previously unknown peroxisomal proteins. Phenotypic studies of selected gene disruption mutants suggests that several of these new peroxisomal proteins play roles in growth on fatty acids, one is involved in peroxisome biogenesis and at least two are required for synthesis of lysine, a heretofore unrecognized role for peroxisomes. These results expand our understanding of peroxisome content and function, demonstrate the utility of CoSMoS for context-sensitive motif scanning, and point to the benefits of improved in silico genome analysis.

Modulation of oncogenic potential by alternative gene use in human prostate cancer

Only a small percentage of primary prostate cancers have genetic changes. In contrast, nearly 90% of clinically significant human prostate cancers seems to express high levels of the nuclear phosphoprotein pp32 by in situ hybridization. Because pp32 inhibits oncogene-mediated transformation, we investigated its paradoxical expression in cancer by comparing the sequence and function of pp32 species from paired benign prostate tissue and adjacent prostatic carcinoma from three patients. Here we demonstrate that pp32 is expressed in benign prostatic tissue, but pp32r1 and pp32r2, closely-related genes located on different chromosomes, are expressed in prostate cancer. Although pp32 is a tumor suppressor, pp32r1 and pp32r2 are tumorigenic. Alternative use of the pp32, pp32r1 and pp32r2 genes may modulate the oncogenic potential of human prostate cancer.

[Using lux genes marker technique to track Pseudomonas chlororaphis PL9L in cotton rhizosphere]

Tn7-luxCDABE marker system was successfully transferred into Pseudomonas chlororaphis (strain PL9) by means of transformation and conjugation and a stable lux-marked strain PL9L was obtained. The colonizing dynamics and distribution of the luminescent bacteria PL9L in the rhizosphere of cotton planted in pots and rhizoboxes were studied by the methods of X-ray film imaging and enumeration of luminescent colonies on agar media, The results of pot culture experiment showed that PL9L successfully colonized in the rhizosphere of cotton. In pot cultures of sterile soil the highest colonizing level(3.1 x 10(2) cfu/g root soil) was reached on 6th day after seeds sown; On 56th day, the population of PL9L tended to stable and decreased to 1.7 x 10(9) cfu/g root soil) but in pot cultures of unsterile soil, the highest colonizing level(1.1 x 10(9) cfu/g root soil) was reached on 8th day. On 46th day, the population of PL9L tended to a stationary state, the numbers of them were 1.4 x 10(2) cfu/g root soil. The results of rhizobox culture experiment showed that PL9L spread from seeds toward the direction of root tip, but not synchronized with the stretch of roots. 6 days after seeds sown, in rhizobox culture of sterile soil, PL9L spread 12.0 cm below seeds, but in non-sterile soil was 11.0 cm. In the region of cotton root tip, PL9L were not detected.

[Clinical study on pathologic changes of umbilical cord vessels in pregnancy induced hypertension]

OBJECTIVE

To evaluate the relationship between the pathologic features of umbilical cord vessels and the severity of disease in pregnancy induced hypertension (PIH).

METHODS

The umbilical cord vessels of forty-five women with PIH and thirty normal term-pregnant women (control group) were observed under light microscopy; the three parts of cord i.e. near placenta, near fetus and middle section of twenty women with PIH selected randomly were observed as well.

RESULTS

There were no different pathologic changes in the 3 parts of umbilical cord in PIH; Forty-five women with PIH were categorized into three groups according to the degree of lesions: no lesion (n = 6), mild (n = 13) and severe (n = 26). The pathologic changes of umbilical vessels in moderate and severe PIH were more severe than those in mild PIH (P < 0.05, P < 0.01). However, there were no apparent pathologic changes in the control. The pathologic changes of umbilical vessels in PIH had significant relationship with mean arterial pressure (MAP), neonatal outcome and urinary protein.

CONCLUSIONS

The pathologic changes of umbilical vessels can reflect the characteristic lesion of PIH and are parallel with the severity of disease; and there is a homogeneity in pathomorphology of umbilical cord.

[Physical simulation of radial artery displacement]

A previous developed physical cardiovascular simulation is used to investigate the displacement of radial artery during a cardiac cycle. Simulation result shows that the displacement is much greater than the change in the radius of the radial artery. The result is similar to the clinical observation reported before. Based on the simulation result, it is suggested that the displacement of radial artery plays an important part in the Maixiang (pulse condition), which is one of the most important contents of diagnostics in Traditional Chinese Medicine.

[A methodological study on the detection of myocardial ultrasonic integrated backscatter]

The cyclic fluctuation of ultrasonic integrated backscatter(IB) of myocardium has been found to be a potential indicator of clinical significance in the diagnosis of myocardial ischemia. To investigate the feasibility of such a technique, a clinical IB testing system is established in our laboratory. Six male subjects with no history of heart diseases were tested by using this system. Based on the clinical data obtained during the tests, the effects of echo position, bandwidth, and different calculation algorithms on IB value were analyzed and compared. The results are available to provide a guideline for the design of instrumentation for IB detection.

[The therapeutic effect of purified human leucocytic interferon-alpha on hemorrhagic fever with renal syndrome]

In order to know the therapeutic effect of purified human leucocytic interferon-alpha on hemorrhagic fever with renal syndrome diagnosed early (< or = 5 days). We treated 23 cases with clinical prognosis and antiviral effect significantly better than those of 21 cases in a random control group. The membrane protein (MP), nucleo protein (NP) in peripheral blood mononuclear cells (PBMC) and urine, the serum antibodies to MP and NP were determined before treatment and 2, 4, 6, 8, 10 days after the beginning of the treatment. The results showed that in the treatment group, the expressin of MP and NP in PBMC were significantly depressed. The rate of negative turning of MP and NP in PBMC was 65.22% (15/23) and 69.57% (16/23) in 10 days, while in the control group, it was 19.05% (4/21) and 14.29% (3/21). The rate of negative turning of MP and NP in urine were 78.57% (11/14) and 90.91% (10/11) and that in the control group was 30.00% (3/10) and 16.66% (1/6). There was a significant difference between the two groups (P < 0.01). The results indicated that IFN-alpha could attenuate the lesions caused directly by virus, improve patients condition and raise the cure rate through depressing the expression of the virus.

Questionnaire items that predict asthma and other respiratory conditions in adults

The International Union Against Tuberculosis and Lung Disease questionnaire is widely used in epidemiologic studies of adult asthma. We examined whether the symptom questions could be classified into groups that represent different "syndromes," and whether some questions are better for predicting asthma than others. We analyzed questionnaire data from a population sample of 1,527 adults aged 18 to 55 years using factor analyses to classify the 17 respiratory symptom questions into four different groups that we termed asthma, cough, breathlessness, and urgent medical visit. The urgent medical visit was a subset of asthma. These four "syndromes" had good validity when measured against airway responsiveness to histamine, atopy to common allergens, lung function, smoking status, and body mass index. Questions that predicted asthma syndrome were those that asked about wheeze at rest or following exercise, asthma attack, chest tightness, and shortness of breath at rest. Questions about cough identified a different group of subjects who apparently did not have asthma. Questions of breathlessness did not aggregate with "asthma" or with "cough syndrome." The identification of particular questions that measure different respiratory conditions is important for epidemiologic studies when short questionnaires or more precise definitions are required.

[Production, identification and redirected cytotoxicity of CD3/CD19 bispecific monoclonal antibody]

OBJECTIVE

To prepare CD3/CD19 bispecific monoclonal antibody (BsAb) and study its biological effects.

METHODS

The CD3/CD19 BsAb was prepared by using hybri-hybridoma technique. The presence of BsAb was demonstrated by double-isotype ELISA and cell conjugate assay.

RESULTS

We obtained three strains of CD3/CD19 quadromas, including a stable one. 51Cr release assay showed that CD3/CD19 supernatants, CD3/CD19 purified antibody and CD3/CD19 chemical heterocongjugate greatly enhanced the cytotoxic activity of CD3 AK cells against Nalm-6 cells (P < 0.05-0.001).

CONCLUSIONS

The CD3/CD19 BsAb we prepared was efficient in redirecting activated T cells against target tumor cells. This indicates that the CD3/CD19 BsAb has potential value of clinical use.

[Clinical and experimental study on treatment of acute alcohol intoxication with xiangnaojing injection]

OBJECTIVE

To study the therapeutical mechanism of traditional Chinese medicine Xingnaojing injection (XNJI) for acute alcohol intoxication.

METHODS

XNJI was used in treating the experimental model rabbits (n = 26) and the patients (n = 8) admitted to the emergency department with acute alcoholism. Before and after the treatment, beta-EP, superoxide anion (free radicals) and SOD were measured.

RESULTS

XNJI could enhance the regaining consciousness of rabbits and patients, simultaneously reduce the concentration of beta-EP in plasma to the normal level (drunk rabbits 127.09 +/- 13.67 ng/L, normal rabbits 41.48 +/- 7.46 ng/L. P < 0.01, drunk patients 292.97 +/- 14.85 ng/L, normal people 221.60 +/- 15.95 ng/L, P < 0.01). The concentration change of superoxide anion (free radicals) in plasma of rabbits and patients was similar to beta-EP (drunk rabbits 313.39 +/- 15.64 u/L, normal rabbits 254.27 +/- 21.71 u/L, P < 0.01; drunk patients 278.47 +/- 11.48 u/L, normal people 159.92 +/- 11.51 u/L, P < 0.01), and SOD was inversely changed (drunk rabbits 53.57 +/- 6.48%, normal rabbits 77.18 +/- 7.89%, P < 0.01; drunk patients 43.76 +/- 7.84%, normal people 82.53 +/- 4.33%, P < 0.01).

CONCLUSIONS

XNJI is similar to Naloxone in pharmacologic action. And it is an effective antioxidant. It can be used for treating alcoholism.

[Cell density and expression of proliferating cell nuclear antigen (PCNA) in the lens epithelium of children and aging patients with cataract]

OBJECTIVE

To determine the cell density and expression of proliferating cell nuclear antigen (PCNA) in the lens epithelium of children and aging patients with cataract.

METHODS

The lens epithelial cells (LECs) of the central area were examined in two groups, children (less than 12 years old) and senile persons (51 - 80 years old). The densities of LECs in the two groups were calculated with samples stained with hematoxylin and eosin (HE) staining, and the PCNA was tested immunohistochemically. The integral optical density (IOD) of PCNA expression was measured through a medical color image analysis system.

RESULTS

The densities of LECs in children and senile persons were 5,020.25 +/- 246.01 cells/mm(2) and 4,340.00 +/- 240.95 cells/mm(2) (P < 0.05), the IODs were 2.89 +/- 0.57 and 2.13 +/- 0.63 (P < 0.05) respectively.

CONCLUSION

The LEC counting and IOD values in children eyes are significantly higher than that of senile persons, suggesting that they be one of the important factors in the formation of posterior capsular opacification (PCO) or after cataract in children eyes.

Overexpression of CuZnSOD gene suppresses the growth of hepatocellular cancer cell line HepG2

OBJECTIVE

To explore the inhibiting effect of superoxide dismutase (SOD) on the growth of hepatocellular cancer cell line HepG2.

METHODS

By gene transfer technique, hepatocellular cancer cells (HepG2) were transfected with a retroviral vector containing human CuZnSOD cDNA. The elevated SOD gene expression of the transfected cells was compared with the parental and neo control cells.

RESULTS

Compared to the control cells, cancer cells transfected with SOD gene showed an inhibited cell growth, a reduced number of cells in S phase and decreased clone forming ability in soft agar, as well as a smaller tumor size formed in nude mice.

CONCLUSION

The overexpression of CuZnSOD gene could, to certain extent, suppress the cell growth of hepatocellular cancer cell line HepG2.

A simulation study on +Gz protection afforded by extended coverage anti-G suits

Computer simulation studies using our newly developed mathematical model of human cardiovascular (CV) system were performed to investigate the effect of bladder coverage and inflation schedule of anti-G suit on G protection and CV response. The simulation results agree well with centrifuge experiments. The study demonstrates that additional +Gz protection provided by the extension of the bladder coverage depends mainly upon the pressure transmission efficiency to the underlying tissues and vessels. Although G tolerance increases clearly with the increase of suit inflation schedule, the tendency of increase seems slower when inflation schedule becomes higher than 10 kPa/G.

Design and development of an interactive medical teleconsultation system over the World Wide Web

The objective of the medical teleconsultation system presented in this paper is to demonstrate the use of the World Wide Web (WWW) for telemedicine and interactive medical information exchange. The system, which is developed based on Java, could provide several basic Java tools to fulfill the requirements of medical applications, including a file manager, data tool, bulletin board, and digital audio tool. The digital audio tool uses point-to-point structure to enable two physicians to communicate directly through voice. The others use multipoint structure. The file manager manages the medical images stored in the WWW information server, which come from a hospital database. The data tool supports cooperative operations on the medical data between the participating physicians. The bulletin board enables the users to discuss special cases by writing text on the board, send their personal or group diagnostic reports on the cases, and reorganize the reports and store them in its report file for later use. The system provides a hardware-independent platform for physicians to interact with one another as well as to access medical information over the WWW.

Experimental model of renovascular hypertension

OBJECTIVE

To establish a model of renovascular hypertension.

METHODS

A 4/0 resorbable chromic catgut ligature was used to ligate subtotally the renal arteries of 18 dogs, forming experimental renovascular hypertension steadily. Blood pressure, plasma renin activity, the ultrastructural changes of juxtaglomerular apparatus and renal artery wall were studied after the constriction.

RESULTS

It was reasonable that renal blood flow measured with an electromagnetic flowmeter was reduced by 30% after the constriction. The pathological changes of the induced renal artery stenosis were similar to those of fibromuscular dysphasia.

CONCLUSION

The findings provide valuable evidence for the treatment of renovascular hypertension.

Optimization and mechanism of step-leap respiration exercise in treating of cor pulmonale

The interaction between cardiovascular system and the respiratory system is complicated and may be used for the rehabilitation of the cor pulmonale disease. To study the effects of different breathing mode on the cardiac and pulmonary systems, a mathematical model is established based on the previous work. Using this model, computer simulation experiments are carried out for searching an optimal respiration mode in treating of cor pulmonale disease. Results indicate that the step-leap respiration mode could provide a better assistant to the rehabilitation of the cor pulmonale patients in the sense of increasing coronary flow, reducing pulmonary arterial pressure and reducing the working load for the right heart. This result is also proven by the clinical experiments. This work may suggest that a proper directed respiration exercise can be used in the treatment of cor pulmonale disease.

[The studies on MTS1/p16 gene deletion during transformation of human bronchial epithelial cells]

OBJECTIVE

To detect the deletion of MTS1/p16 and the expression of P16 protein during the transformation of human bronchial epithelial cell line M.

METHODS

Dual-color fluo-rescence in situ hybridization (FISH), immunohistochemical staining and western blot analysis were carried out.

RESULTS

No deletion of MTS1/p16 gene was found in MP18 cells of the cell line M. But partial deletions occurred in the MP36 and MP120 cells of the cell line M. Immunohistochemical analysis and western blot test showed lower expression of P16 protein in the MP120 cells than in MP20 cells.

CONCLUSIONS

MTS1/p16 gene deletion contributes to the malignant transformation of the human bronchial epithelial cell line M. Also FISH is a useful technique in detecting gene deletion.

[Effects of the glucoprotein component of musk on functions of rat polymorphonuclear leukocytes activated by LTB4 in vitro]

To investigate the effects of musk-1, a glucoprotein component isolated from the water extract of musk, on some functions of rat polymorphonuclear leukocytes activated by LTB4, an in vitro incubation system with rat polymorphonuclear leukocytes was used. The superoxide anion production was determined by cytochrome C reduction, and the beta-glucuronidase and lysozyme release was quantitated by enzyme reactions in which phenolphthaleinglucuronic acid and micrococcus lysodeikticus were used as the substrates. In comparison with the control, musk-1 at final concentrations of 1 microgram/ml-100 micrograms/ml can increase the superoxide anion production by 28.7%-202.1% and decrease the beta-glucuronidase and lysozyme release by 3%-46% and 6%-32% respectively in rat polymorphonuclear leukocytes. It is concluded that musk-1 can significantly affect the functions of rat polymorphonuclear leukocytes activated by LTB4. One of the mechanisms of this anti-inflammatory action of musk may consist in the inhibition of lysosomal enzyme release.

[An internet based medical communication server]

The telemedicine and medical conference usually need multi-point to multi-point communication. Because the communication users can be patients, specialists or medical centers, they have different communication ratios and different physical connection, therefore, this kind of communication is complicated and limited by the communication ratios. In this paper, to meet the requirements of medical communication, we presented a concept of medical communication server which is able to receive data packages and deliver them according to the request of clients, and described its implementation in Windows 95 environment by using Windows Sockets.

The design and preliminary evaluation of a home electrocardiography and blood pressure monitoring network

A home electrocardiography (ECG) and blood pressure (BP) monitoring network was established in Beijing. The network consisted of three parts: (1) the home ECG and BP monitoring devices; (2) the monitoring centre at the hospital; and (3) the data communication network, for which we chose the public telephone network. The system was tested in our university hospital for two months with 30 patients and six normal volunteers. A preliminary evaluation by the users indicated that the system was acceptable in terms of its efficiency and effectiveness. This paper describes the system design, the preliminary testing procedure, and results.

Simulation study of the interaction between respiration and the cardiovascular system

Many studies have been done on the respiratory and the cardiovascular system. Among them, only a few are on the interaction of these two physiologic systems. To explore the mechanism of the integration of these two physiological systems, computer simulation has been done; we report the preliminary results obtained in our laboratory. In this study, a mathematical model of the cardiovascular system integrated with the respiratory mechanical system has been established. The model is based on our previous work on cardiovascular modeling. The previous lumped lung model has been replaced by a multielement model with more detail. Interthoracic and abdominal pressures and modeled as external pressure sources on the related cardiovascular elements. Using this model, a sequence of simulation studies have been carried out. Different respiratory modes have been simulated and the different effects are observed in the simulation results. The results indicate that by following a certain respiratory pattern, the circulation status can be improved. These results agree with clinical observations.

A communication server for telemedicine applications

The telemedicine applications, in some cases, need multipoint-to-multipoint communication. To meet the requirement of telemedicine communication, the development of a medical communication server is proposed in this paper. To make a working, as well as cost-effective, communication platform for the telemedicine applications, a specially designed communication server model is proposed in this work. This server is able to provide an effective multipoint-to-multipoint communication service for any level applications in telemedicine. The implementation program of this server is developed in a Windows'95 environment by using a winsocket. The trial application testing in a telemonitoring system is also presented to demonstrate the feasibility of taking such a structure with the server. By using the architecture of such a communication server in telemedicine applications, the multipoint-to-multipoint communication is easily managed and the communication processes are simplified and well controlled by the server.

Measurement of spontaneous transfer and transbilayer movement of BODIPY-labeled lipids in lipid vesicles

An assay was developed to study the spontaneous transfer and transbilayer movement (flip-flop) of lipid analogs labeled with the fluorescent fatty acid, 5-(5,7-dimethyl BODIPY)-1-pentanoic acid (C5-DMB-) in large unilamellar lipid vesicles comprised of 1-palmitoyl-2-oleoyl phosphatidylcholine (POPC). The assay is based on the concentration-dependent changes in fluorescence intensity that occur when donor vesicles containing a C5-DMB-lipid are mixed with nonfluorescent acceptor vesicles. A kinetic model was developed to describe the time-dependent changes in concentration of a lipid undergoing both spontaneous transfer between unilamellar vesicles and transbilayer movement within the vesicle membranes, and a mathematical solution was obtained. Data were obtained using C5-DMB-labeled analogs of sphingomyelin (C5-DMB-SM), ceramide (C5-DMB-Cer), phosphatidylcholine (C5-DMB-PC), and diacylglycerol (C5-DMB-DAG), and kinetic parameters for each lipid were determined using a nonlinear least-squares fitting program. The half-times for interbilayer transfer of the lipids were C5-DMB-SM (21 s) < C5-DMB-PC (350 s) approximately C5-DMB-Cer (400 s) << C5-DMB-DAG (100 h). C5-DMB-Cer (t1/2 approximately 22 min) and C5-DMB-DAG (t1/2 approximately 70 ms) exhibited rapid spontaneous transbilayer movement, while C5-DMB-SM (t1/2 approximately 3.3 h) and C5-DMB-PC (t1/2 approximately 7.5 h) moved across the bilayer very slowly. These results provide a basis for interpreting the behavior of these lipid analogs in cells.

[The study of women's bone density in Beijing]

Bone mass of 434 healthy women aged from 20-65 years was measured at both distal and mid-radius of the non-dominant arm by using a single-photon absorptiometer (SPA) with an 241Am source (model SD-1000), and bone density and related factors were studied. The bone density in women reached the peak value around 40 years old and the bone loss began around 45 years old. Bone loss was accelerated after menopause, with faster speed in trabecular bone than in cortical bone. The effect of menopause on bone loss was more significant than the effect of advancing age. Among 174 menopausal women, 9.8% had fractures. The bone density of postmenopausal women with history of bone fracture was lower than that of those without fracture. The results of this study suggest that the measurement of bone density can be used to predict the risk of osteoporotic fractures.

[Effect of Salvia miltiorrhizae Composita on erythrocyte membrane phospholipid in patients with coronary heart disease]

OBJECTIVE

To investigate the function of phospholipid metabolism in pathogenesis of coronary heart disease (CHD) and the effect of Salvia miltiorrhizae Composita (SMC) on it.

METHODS

The levels of erythrocyte membrane phospholipid, blood lipid peroxide (LPO), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were determined in the patients with CHD by Thinlayer chromatography and fluorimetry during the treatment of SMC.

RESULTS

Sphingomyelins (SM), phosphatidyl serine (PS), phosphatidyl ethanolamine (PE) and lysophosphatide (LL) of erythrocyte membrane phospholipid were increased in patients with CHD. Phosphatidyl cholines (PC) was lower than control group. Among them, the ratios of SM/PC and PS/PC were significantly higher. In the patients with CHD, LPO was significantly increased and ratios of SOD/LPO and GSH-Px/LPO significantly decreased. After the treatment with SMC, LL, SM, PS and PE of erythrocyte phospholipid and the ratios of SM/PC and PS/PC and LPO were decreased. PC and SOD/LPO were increased.

CONCLUSIONS

The abnormality of erythrocyte membrane phospholipid participate the occurrence and development of CHD. SMC might improve the abnormality of erythrocyte phospholipid and lipid peroxide and possess the effect of regulating phospholipid metabolism.

[Effects of the glucoprotein component of musk on the functions of rat polymorphonuclear leukocytes activated by fMLP in vitro]

To investigate the effects of musk-1, a glucoprotein component isolated from the water extract of musk, on the release of superoxide anion as well as beta-glucuronidase and lysozyme of rat polymorphonuclear leukocytes activated by fMLP. An in vitro incubation system with rat polymorphonuclear leukocytes was used. Superoxide anion production was determined by cytochrome C reduction. beta-glucuronidase and lysozyme release was quantitated by enzyme reactions in which phenolphthaleinglucuronic acid and micrococcus lysodeikticus were as the substrates, respectively. In comparison with control, musk-1 at final concentrations of 1-100 micrograms/ml can increase superoxide anion production by 23.0%-83.6% and decrease beta-glucuronidase and lysozyme release by 7%-47% and 9%-22%, respectively, in rat polymorphonuclear leukocytes. It is concluded that Musk-1 can significantly affect the functions of rat polymorphonuclear leukocytes. Therefore, inhibition of lysosomal enzyme release might be considered as one of the mechanisms of anti-inflammatory role of musk.

[The effect of glucoprotein component of musk on arachidonic acid metabolizing enzymes in rat polymorphonuclear leukocytes]

To investigate the effects of musk-1, a glucoprotein component isolated from the water extract of musk, on arachidonic acid metabolizing enzymes, which include phospholipase A2(PLA2), 5-lipoxygenase (5-LO), and cyclooxygenase (COX), in rat polymorphonuclear leukocytes, an in vitro incubation system with rat polymorphonuclear leukocytes or homogenate supernatant of the same cells was used. In comparison with control, musk-1 at final concentrations of 1-100 micrograms/ml can increase AA release from PMNL by 6.0%-21.6%, decrease LTB4 biosynthesis in homogenate supernatant of the cells by 9%-81%, but increase 6-keto-PGF1 alpha production by 18.2%-85.4%.

[The monitoring of post cesarean section uterine scal with B-ultrasonographic and clinical detections]

OBJECTIVE

To find out an effective method for monitoring the healing of uterine incision after cesarean section.

METHODS

1,145 patients with cesarean section were monitored by B-ultrasonography. In 19 patients who revealed fluid mass in uterine incision, 10 cases were treated by percutaneous drainage under sonographic guidance and 9 cases as control.

RESULTS

According to sonographic characteristics, uterine incision healing can be divided into three conditions: normal type revealing a smooth strong echo's light band in uterine incision (93.97%), inflammatory type revealing an uneven parenchymatous light mass (3.67%), and fluid mass with inflammation revealing a complex light mass with low echo's or anechoic area (2.36%). There were abnormal clinical signs in most cases of inflammation. The percutaneous drainage therapy showed marked effect.

CONCLUSIONS

The monitoring of uterine incision healing by B-ultrasonography plays an important role in preventing late post-partum hemorrhage.

[A simulation study on G protection using tilt-back seat]

A mathematical model of human cardiovascular system with cardiopulmonary interaction was developed basing on the previous works of Jaron, Bai jing, et al (1988, 1992). The model of pulmonary circulation was improved and intrathoracic pressure, intra-abdominal pressure and pulmonary alveolar pressure were introduced in the new model. Computer simulation experiments using this model for human relaxed tolerance to rapid onset (1 G/s), gradual onset (0.1 G/s), and high onset (5 G/s) G exposures, at seat back angles of 13 degrees, 30 degrees, 45 degrees, 55 degrees, 65 degrees, 75 degrees, and 85 degrees, were performed. The simulation results are consistent with the experimental data obtained from reported centrifuge experiments. The tolerance increase by tilt back seat may be attributed to the following three factors: (1) decrease of retinal-aorta hydrostatic distance; (2)decrease of venous pooling in the lower body; (3)decrease of G onset rate in Z axis.

[Simulation study on the blood volume feedback control]

To describe the relationship between blood volume and the cardiac function mathematically, a computer cardiovascular model, was developed including a systemic circulation, a heart and a pulmonary model and a blood volume feedback control. Simulation results indicate that the chronic heart failure could be compensated by increasing the blood volume to maintain the proper arterial pressure. Deterioration in heart failure causes an increase in blood volume, as well as increases in heart volume and cardiac energy consumption. These results are in agreement with the clinical data and results reported in the literature. The simulation also shows that for a predetermined ventricular contractility, an adequate increase in blood volume will increase the heart volume but decrease the cardiac energy consumption and lead the heart to work in an optimum condition.

A home electrocardiography and blood pressure telemonitoring system

A home electrocardiography (ECG) and blood pressure telemonitoring system for cardiac patients was installed in the Macau region. The monitoring centre was established in the emergency unit at the Government Hospital of Macau. The first users were 10 cardiovascular patients selected by a physician. The average age of these users was 61 years (range 30-78). The results of a three-month trial showed that the system was easy to operate and technically reliable. It was found to be helpful for cardiac patients. The most significant problem during the trial was electrical noise from the ECG electrodes.

Unique long terminal repeat U3 sequences distinguish exogenous jaagsiekte sheep retroviruses associated with ovine pulmonary carcinoma from endogenous loci in the sheep genome

Ovine pulmonary carcinoma (OPC) is a contagious lung cancer of sheep that is presumed to be caused by an exogenous retrovirus of sheep, jaagsiekte sheep retrovirus (JSRV). The sheep genome carries 15 to 20 copies of endogenous sheep retrovirus (ESRV) loci that hybridize to JSRV DNA probes. In order to clarity the etiologic roles of ESRV and an exogenous JSRV-like retrovirus (exJSRV) in OPC, we assessed sequence differences between ESRV and JSRV. Molecular characterization of six ESRV loci revealed restriction sites specific for JSRV. Nucleotide sequences of ESRVs from sheep of different breeds were similar to those of JSRV in structural genes but divergent in U3. Therefore, primers specific for the U3 sequences of exJSRV were designed for use in the PCR. Of 13 tumor DNAs tested by PCR with these exogenous-virus U3 primers, 8 produced DNA fragments that hybridized with the JSRV gag probe, but neither lung DNAs from healthy sheep nor DNAs from nontumor tissues of diseased sheep produced similar DNA fragments. exJSRV PCR products from tumor DNAs of sheep with OPC from three continents had restriction profiles similar to each other but different from those of ESRVs upon digestion with EcoRI, HindIII, NdeI, KpnI, and ScaI. These exjSRVs could be classified into two genotypes according to U3 sequences and restriction profiles. U3 sequences of exJSRV proviruses in tumors strongly resembled those of JSRV but differed from those of ESRVs, suggesting that exJSRVs, rather than ESRVs, are primarily associated with oncogenesis in OPC.

The effects of intra-aortic balloon pumping combined with coronary sinus interventions on failing hearts: a model study

Cardiac energy balance is an important factor in evaluating cardiac function. In this work, the effects of different assist modalities and their combinations on cardiac energy balance and global cardiac function have been investigated. The simulation results indicate that coronary sinus interventions (CSIs) can provide myocardium with more energy than IABP when coronary arterial stenosis is serious. However, IABP can decrease myocardial energy consumption and enhance cardiac output, which cannot be done by CSIs, under the condition of impaired myocardial contractility. Therefore, we conclude that the combination of IABP and CSIs is the best way of assisting failing circulation.

Characterization of SDS--PAGE-separated proteins by matrix-assisted laser desorption/ionization mass spectrometry

A new strategy to characterize SDS--PAGE-separated proteins with MALDI MS is described. The proteins, electroblotted onto nitrocellulose after SDS--PAGE separation and stained with reversible Ponceau S dye, are readily recovered by dissolving the membrane in matrix solutions prepared with acetone. The resulting mixtures are amenable to direct MALDI MS analysis, which provides a rapid and accurate means of measuring the molecular weights of SDS--PAGE-separated proteins and of peptides that result from CNBr digestion of proteins on the nitrocellulose membrane. Compared with the traditional elution method, this procedure provides more efficient detection of proteins and peptides, especially the higher molecular weight proteins from the membrane. As little as 3.5 pmol of lysozyme and 15 pmol of bovine albumin loaded onto a gel can be detected using this method. The detection sensitivity is higher than or comparable to that of the traditional Coomassie Brilliant Blue staining procedure.