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Zheng Tang

Publications and source records attributed to Zheng Tang.

18 recordsLinked to original sources
PubMed2006

An aggressive systematic strategy for acute respiratory distress syndrome caused by severe pneumonia after renal transplantation.

Acute respiratory distress syndrome (ARDS) caused by pneumonia after renal transplantation was usually associated with overimmunosuppression and high mortality rate. We evaluated the efficacy of an aggressive systemic protocol including strategies improving body's immune function. Twenty-one recipients were enrolled in this study. Patients were subjected to a protocol including (i) withdrawal of most immunosuppressants, (ii) early use of immunoenhancers and continuous renal replacement therapy (CRRT), (iii) reasonable administration of antibiotic regimen, (iv) prompt mechanical ventilating strategy, and (v) adequate nutrition. Immunosuppressants were adjusted according to the value of CD4+, CD8+T lymphocytes in peripheral blood. CRRT was conducted at once when patients were admitted to the intensive care unit (ICU), regardless the graft function. Thirteen (62%) survived and eight died finally. This is a high survival rate for this kind of patients. Eighteen patients had received thymosin treatment. All patients who survived experienced renal allograft dysfunction during CRRT, but when CRRT stopped, the function of all grafts gradually recovered. No acute rejection episodes were documented during the treatment. The aggressive systemic protocol including strategies improving the body's immune function and CRRT can improve the outcome of patients with ARDS after renal transplantation. The count of CD4+, CD8+T lymphocytes of peripheral blood is useful in the adjustment of immunosuppressants and the prediction of patient outcome.

Adjuvants, Immunologic↗
PubMed2006

Pulmonary Lophomonas blattarum infection in patients with kidney allograft transplantation.

The aim of the study was to analyse the clinical manifestation and management of pulmonary Lophomonas blattarum infection in four allograft transplantation recipients retrospectively. Four patients with pulmonary L. blattarum infection were diagnosed by using Fiberoptic bronchoscopy (FOB) and bronchoalveolar lavage (BAL) examination. Their clinical manifestation and management are summarized. Four cases of pulmonary L. blattarum were found during the period from the second month to the third month after transplantation. Concurring infection by other pathogens was found in three of them. Common initial symptoms included fever (>38 degrees C) without cough and breathlessness. Lower lobe shadowing could be found on chest X-ray. Body temperature decreased to the normal range in three patients and to 37.5 degrees C in the other one, after intravenous injection of metronidazole and tapering immunosuppressant. Radiological examination confirmed improved health condition of the patients afterwards. Two patients received repeated FOB and only dead L. blattarum was found. Pulmonary L. blattarum infection in allograft transplant recipients carry relatively obscure initial symptoms. Possible L. blattarum infection needs to be screened in post-transplantation pulmonary infection patients with similar symptoms, especially in those who respond poorly to anti-infection treatment. Microscopic examination of BAL fluid can help to identify pulmonary L. blattarum infection and metronidazole is an ideal treatment choice.

Adult↗
PubMed2005

Malignant hypertension in patients with idiopathic IgA nephropathy.

BACKGROUND: Idiopathic IgA nephropathy is one of the main causes of secondary malignant hypertension, especially in Chinese population. But little information has been available about malignant hypertension secondary to IgA nephropathy (IgANMHT). The purpose of this study is to evaluate the clinico-pathological features and outcomes of IgANMHT patients. METHODS: A case control retrospective study was carried out in 45 cases of IgANMHT and 26 cases of primary malignant hypertension (PMHT) diagnosed by renal biopsy. Their clinical features and pathological findings were investigated. Their average follow-up time was 37.4 months. Univariate analysis and multivariate Cox regression analysis were performed to select variables to predict renal survival. RESULTS: In the study, 1.2% of all the IgA nephropathy patients presented malignant hypertension. The amounts of urine protein excretion and red blood cells in IgANMHT patients were significantly higher, while the levels of serum creatinine were significantly lower than those in PMHT patients. The glomerular injury in IgANMHT patients was more severe than that in PMHT patients. The two characteristic vascular lesions of primary malignant hypertension, proliferative endoarteritis and fibrinoid necrosis were also found in IgANMHT patients but with less severity. Renal survival of IgANMHT patients was significantly higher than that of PMHT patients (p = 0.0043). However, log-rank test showed no significant difference in the renal survival between IgANMHT and PMHT patients with similar SCr levels at admission. Multivariate Cox regression analysis revealed that a high amount of urine protein excretion(> or =1.5 g/24 h), mesangial proliferation and elevated serum creatinine (> or =2 mg/dl) were statistically independent risk factors for renal prognosis (RR = 1.90, 2.72, 2.84, respectively). Conversely, strict blood pressure control had a favorable effect on renal prognosis. CONCLUSION: The clinico-pathological features and outcomes of IgANMHT patients were different from those of PMHT patients. The renal survival of IgANMHT patients was poor, which was determined by many factors. Early control of proteinuria, early monitoring and strictly controlling blood pressure may contribute to the renal survival.

Adolescent↗
PubMed2005

Significance of vascular endothelial growth factor expression in renal tissue of patients with preeclamptic nephropathy.

OBJECTIVE: It was the aim of this study to evaluate the distribution and expression of vascular endothelial growth factor (VEGF) in kidneys of patients with preeclamptic nephropathy and their relationship with clinical and pathological manifestations. METHODS: From May 1993 to August 2004, 19 patients with a mean age of 28.1 +/- 4.53 years (range 23-40), diagnosed with preeclamptic nephropathy by renal biopsy, were enrolled in this study. Fifteen were nulliparous and 4 multipara. Their renal tissues were subjected to immunohistochemical staining by a four-layer peroxidase-antiperoxidase method using monoclonal anti-VEGF. Residual normal renal tissue obtained at nephrectomy served as control. The relationship between the expression pattern of VEGF and clinicopathological features was also investigated. RESULTS: The expression of VEGF markedly increased in renal tissues of patients with preeclamptic nephropathy at the early stage of gestation termination in comparison with normal controls. However, over time, it gradually decreased and reached the level of normal controls (100 vs. 71.43 vs. 20%, p < 0.05). The degree of endothelial proliferation in the glomeruli was closely related to the expression of VEGF, which was stronger in patients with diffuse endothelial proliferation than in those with segment proliferation (p < 0.05). In addition, there was a proportional relationship between the expression of VEGF and the level of urinary protein excretion (p < 0.05). CONCLUSION: The patients with preeclamptic nephropathy showed strong expressions of VEGF in glomeruli, which were closely associated with glomerular endothelial lesions and proteinuria, and over time, gradually weakened to normal level after gestation termination.

Adult↗
PubMed2005

Influence of CYP3A5 and MDR1 polymorphisms on tacrolimus concentration in the early stage after renal transplantation.

OBJECTIVE: Tacrolimus is an immunosuppressive drug with a narrow therapeutic range and wide interindividual variation in its pharmacokinetics. Cytochrome P450 (CYP) 3A and P-glycoprotein (P-gp, encoded by MDR1) play an important role in the absorption and metabolism of tacrolimus. The objective of this study was to evaluate whether or not CYP3A5*1/*3 or MDR1 C3435T polymorphisms are associated with the tacrolimus concentration per dose. METHODS: CYP3A5 and MDR1 genotypes were determined by polymerase chain reaction followed by restriction fragment length polymorphism analysis in 118 Chinese renal transplant patients receiving tacrolimus. Whole blood trough tacrolimus concentration was measured by enzyme-linked immunosorbent assay and dose-adjusted concentration (ng/mL per mg/kg/d) was calculated at 1 wk, 1 month, and 3 months after transplantation. RESULTS: The dose-adjusted concentration of CYP3A5*1/*1 and *1/*3 patients was significantly lower than *3/*3 patients (32.8 +/- 17.7 and 41.6 +/- 15.8 vs. 102.3 +/- 51.2 at 1 wk; 33.1 +/- 7.5 and 46.4 +/- 12.9 vs. 103 +/- 47.5 at 1 month; 35.3 +/- 20.9 and 59.0 +/- 20.6 vs. 150 +/- 85.3 at 3 months after transplantation respectively). At 1 wk, 46% of the CYP3A5*1 allele carriers had a tacrolimus concentration lower than 5 ng/mL and 77% lower than 8 ng/mL, whereas 20% of the *3/*3 patients had a concentration higher than 20 ng/mL. There was a mild difference between *1/*1 homozygotes and *1/*3 heterozygotes at 1 and 3 months after transplantation. No difference was found among the MDR1 genotypes. CONCLUSION: CYP3A5*1/*3 polymorphisms are associated with tacrolimus pharmacokinetics and dose requirements in renal transplant recipients. Pharmacogenetic methods could be employed prospectively to help initial dose selection and to individualize immunosuppressive therapy.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2005

A modified error backpropagation algorithm for complex-value neural networks.

The complex-valued backpropagation algorithm has been widely used in fields of dealing with telecommunications, speech recognition and image processing with Fourier transformation. However, the local minima problem usually occurs in the process of learning. To solve this problem and to speed up the learning process, we propose a modified error function by adding a term to the conventional error function, which is corresponding to the hidden layer error. The simulation results show that the proposed algorithm is capable of preventing the learning from sticking into the local minima and of speeding up the learning.

Algorithms↗
PubMed2004

3D flash lag illusion.

Objective of this research is to study the presence of 3D flash lag illusion created by a moving object that has a motion-in-depth and a flash object. An object consisting of two thin sticks was simulated to approach the subject who observed it with a stereoscope. In the process of approaching, another stick was briefly presented in the middle of the moving sticks. Five human subjects took part in our experiments and all perceived 3D flash lag illusion. The perceived depth created by 3D flash lag illusion was measured by two different psychophysical experiments, by use of a vernier caliper and by a method of nulling with another depth cue. We studied relation between the perceived depth and the presentation distance. The experimental results indicate that the perceived gap by 3D flash lag illusion is independent from the presentation distance.

Adult↗
PubMed2004

A hopfield network learning method for bipartite subgraph problem.

In this paper, we present a gradient ascent learning method of the Hopfield neural network for bipartite subgraph problem. The method is intended to provide a near-optimum parallel algorithm for solving the bipartite subgraph problem. To do this we use the Hopfield neural network to get a near-maximum bipartite subgraph, and increase the energy by modifying weights in a gradient ascent direction of the energy to help the network escape from the state of the near-maximum bipartite subgraph to the state of the maximum bipartite subgraph or better one. A large number of instances are simulated to verify the proposed method with the simulation results showing that the solution quality is superior to that of best existing parallel algorithm. We also test the learning method on total coloring problem. The simulation results show that our method finds optimal solution in every test graph.

Algorithms↗
PubMed2004

An annealed chaotic maximum neural network for bipartite subgraph problem.

In this paper, based on maximum neural network, we propose a new parallel algorithm that can help the maximum neural network escape from local minima by including a transient chaotic neurodynamics for bipartite subgraph problem. The goal of the bipartite subgraph problem, which is an NP- complete problem, is to remove the minimum number of edges in a given graph such that the remaining graph is a bipartite graph. Lee et al. presented a parallel algorithm using the maximum neural model (winner-take-all neuron model) for this NP- complete problem. The maximum neural model always guarantees a valid solution and greatly reduces the search space without a burden on the parameter-tuning. However, the model has a tendency to converge to a local minimum easily because it is based on the steepest descent method. By adding a negative self-feedback to the maximum neural network, we proposed a new parallel algorithm that introduces richer and more flexible chaotic dynamics and can prevent the network from getting stuck at local minima. After the chaotic dynamics vanishes, the proposed algorithm is then fundamentally reined by the gradient descent dynamics and usually converges to a stable equilibrium point. The proposed algorithm has the advantages of both the maximum neural network and the chaotic neurodynamics. A large number of instances have been simulated to verify the proposed algorithm. The simulation results show that our algorithm finds the optimum or near-optimum solution for the bipartite subgraph problem superior to that of the best existing parallel algorithms.

Algorithms↗
PubMed2004

Optimal competitive hopfield network with stochastic dynamics for maximum cut problem.

In this paper, introducing stochastic dynamics into an optimal competitive Hopfield network model (OCHOM), we propose a new algorithm that permits temporary energy increases which helps the OCHOM escape from local minima. The goal of the maximum cut problem, which is an NP-complete problem, is to partition the node set of an undirected graph into two parts in order to maximize the cardinality of the set of edges cut by the partition. The problem has many important applications including the design of VLSI circuits and design of communication networks. Recently, Galán-Marín et al. proposed the OCHOM, which can guarantee convergence to a global/local minimum of the energy function, and performs better than the other competitive neural approaches. However, the OCHOM has no mechanism to escape from local minima. The proposed algorithm introduces stochastic dynamics which helps the OCHOM escape from local minima, and it is applied to the maximum cut problem. A number of instances have been simulated to verify the proposed algorithm.

Algorithms↗
PubMed2004

An improved transiently chaotic neural network for the maximum independent set problem.

By analyzing the dynamic behaviors of the transiently chaotic neural network and greedy heuristic for the maximum independent set (MIS) problem, we present an improved transiently chaotic neural network for the MIS problem in this paper. Extensive simulations are performed and the results show that this proposed transiently chaotic neural network can yield better solutions to p-random graphs than other existing algorithms. The efficiency of the new model is also confirmed by the results on the complement graphs of some DIMACS clique instances in the second DIMACS challenge. Moreover, the improved model uses fewer steps to converge to stable state in comparison with the original transiently chaotic neural network.

Algorithms↗
PubMed2004

Lipoprotein glomerulopathy: clinical features and pathological characteristics in Chinese.

BACKGROUND: Lipoprotein glomerulopathy (LPG), once recognized as a rare glomerular disease, has been reported around the world in recent years. In this study, we reported 8 patients of LPG and aimed to explore the clinical features and pathological characteristics of LPG under light microscope, immunofluorescence staining, and electron microscope. METHODS: Clinical manifestations were recorded on the day of renal biopsy. Biochemical patterns of lipids and lipoproteins were detected by routine examination. Plasma concentrations of apo B and apo E were determined by radial immunodiffusion assays. Biopsy specimens were then processed for light microscopy, immunohistochemical staining for immunoglobulins and complement components, and electron microscopy. Glomerular deposition of apo A, B, and E were detected using monoclonal antibodies on cryostatic sections. RESULTS: All of the eight patients presented with edema, microscopic hematuria, severe proteinuria, anemia, and enlarged kidney size. Biochemical profiles revealed high levels of triglycerides, apo B, and apo E. We noted increments of glomerular size and lipoprotein thrombi occupying capillary lumina in the glomeruli of all patients. Immunofluorescence staining showed that the thrombi were strongly positive for apo A, B, and E. Granules and various sizes of vacuoles were observed in the thrombi under electron microscope. CONCLUSION: Compared with previous reports on LPG in other countries, unique clinical and pathological features were found in this group of Chinese LPG patients.

Adolescent↗
PubMed2003

An efficient approximation algorithm for finding a maximum clique using Hopfield network learning.

In this article, we present a solution to the maximum clique problem using a gradient-ascent learning algorithm of the Hopfield neural network. This method provides a near-optimum parallel algorithm for finding a maximum clique. To do this, we use the Hopfield neural network to generate a near-maximum clique and then modify weights in a gradient-ascent direction to allow the network to escape from the state of near-maximum clique to maximum clique or better. The proposed parallel algorithm is tested on two types of random graphs and some benchmark graphs from the Center for Discrete Mathematics and Theoretical Computer Science (DIMACS). The simulation results show that the proposed learning algorithm can find good solutions in reasonable computation time.

Algorithms↗
PubMed2003

Pathological demography of native patients in a nephrology center in China.

OBJECTIVE: To analysis the pathological demography in Chinese patients undergoing renal biopsy from our nephrology center. METHODS: Between January 1979 and October 2000 in Jinling Hospital, Nanjing, China, 10,002 attempts of percutaneous renal were performed in patients with renal disease from 33 provinces of China. The pathological classifications were made according to the WHO criteria of 1982 for renal pathology or the modified WHO criteria of 1995 by a panel of pathologists and nephrologists during routine clinical-pathological rounds. The pathological demography between those specimens collected from 1979 - 1989 and those from 1990 - 1999 was compared. RESULTS: The mean age of the 10,002 subjects undergoing renal biopsy was 31.4 +/- 13.0 years (ranging from 1 to 78 years), with a male to female ratio of 1.3:1; for the 592 renal transplant recipients, the mean age was 37.5 +/- 9.1 years (ranging from 16 to 66 years), with a male to female ratio of 2.36:1. Primary glomerular diseases (PGD) accounted for 71% of the total patients undergoing renal biopsies, secondary glomerular nephritis (SGN) 23%, tubular-interstitial diseases 3.2%, unclassified renal diseases 1.3%, hereditary and congenital renal diseases 1.0%, end stage renal diseases 0.96%, and recently realized or rare renal diseases 0.15%. IgA nephropathy (IgAN) was the most frequent pathological pattern (40%) of PGD, followed by mesangial proliferative lesion (MsPL) (30%), membranous nephropathy (MN) (10%), and focal segmental glomerulosclerosis (FSGS) (6%). Lupus nephritis (LN) was the most pathology common seen (74%) in SGN. During the 22 years of the study period, there was a steady increase in patients with SGN discovered during pathological evaluation of renal disorders. A rise in prevalence was found in IgA nephropathy, MN (both P < 0.001), crescentic glomerulonephritis (P < 0.0001), anti-GBM disease, and hemolytic-uremic syndrome/thrombotic thrombocytopenic purpura related renal damages (both P < 0.001). There was a decrease in endocapillary proliferative glomerulonephritis (P < 0.001) and IgM nephropathy (IgMN) (P < 0.01) from 1990 - 1999 as compared to 1979 - 1989. Infrequent renal pathological entities were also diagnosed in this group, including Niemann Pick disease, Fabry's disease, POEMS syndrome, and lipoprotein glomerulonephropathy. CONCLUSIONS: This is the largest series of renal biopsy data in China, and therefore may reflect the demographic picture of renal diseases in this country. Changes in prevalence of renal pathological entities were reflected in this group of patients over the last 22 years. In primary glomerular diseases, IgA nephropathy is still the most frequently observed pathological pattern. In SGN, LN appeared the most often. Increased prevalence was found in anti-GBM nephritis and HUS/TTP.

Adolescent↗
PubMed2003

Clinical spectrum of diffuse crescentic glomerulonephritis in Chinese patients.

OBJECTIVE: To investigate retrospectively the incidence, distribution of primary disease and clinicopathologic characteristics of diffuse crescentic glomerulonephritis (DCGN) in Chinese patients. METHODS: One hundred and seventy-two consecutive patients diagnosed as having DCGN out of 9828 cases of non-transplanting renal biopsies over sixteen years, were studied. DCGN is categorized into three types according to immunopathologic characteristics. The incidence of this disease, its primary diseases, clinical characteristics and serum antineutrophil cytoplasmic antibodies (ANCAs) were analyzed. RESULTS: The distribution of patients among the three classifications was 8.7% type I, 68.6% type II and 22.7% type III. Clinically, the majority of patients (69.8%) presented rapidly progressive glomerulonephritis (RPGN), but 30.2% manifested a chronic nephritic syndrome or chronic renal failure. In terms of related conditions, 93% were anemic, 61.6% had hypertension, 50.6% oliguria, 45.3% nephrotic syndrome, 43% uremic syndrome and 39.5% displayed gross hematuria. Those patients who were positive in serum for ANCAs had predominantly type III DCGN. Two cases with anti-GBM-antibody crescentic glomerulonephritis and three with lupus nephritis were also positive for ANCAs in serum. CONCLUSION: DCGN is not rare in Chinese patients. A majority of patients in our study presented with RPGN, but 30.2% manifested a chronic renal failure. Lupus patients with DCGN that were positive for ANCAs had more severe vasculitic lesions.

Adolescent↗
PubMed2002

[The inhibitory effect of anti-streptococcus mutans immunoglobulin of yolk on glucan synthesis of Streptococcus mutans].

OBJECTIVES: To observe the inhibitory effect of anti-Streptococcus mutans Hen-egg-yolk (IgY) on glucan synthesis of Streptococcus mutans. METHODS: Determine the glucan with anthrone method after using the different titer of IgY on S.mutans and S.sobrinus. RESULTS: The inhibitory effect of antibody on S.mutans and S.sobrinus synthesis glucan had a similar tendency. The effect of inhibit glucan synthesis was influenced by the titer of antibody. High titer with high inhibition. Begin with the group of 1:16 titer, the group of 1:2 titer showed the highest inhibition (P<0.05). CONCLUSION: The antibody can reduce synthesis of glucan from S.mutans and S.sobrinus.

English Abstract↗
PubMedDate not supplied

Idiopathic IgA nephropathy with diffuse crescent formation.

OBJECTIVE: To investigate the clinicopathological features and outcome of idiopathic IgA nephropathy with diffuse crescent formation in Chinese patients. METHODS: Twenty-five patients with diffuse crescentic IgA nephropathy (DCIgAN), 15 males and 10 females with median age of 28.5, and median disease duration of 5.1 months, were studied. Their clinical, laboratory and pathological features and outcome were investigated. Twenty-one were administered pulse immunosuppressive therapy, and 15 were followed up for more than 6 months. RESULTS: 1.14% had total IgA nephropathy, and 16.4% total diffuse crescentic glomerulonephritis. Clinically, most of patients (88%) showed rapidly progressive glomerulonephritis associated with a high level of serum creatinine (418 +/- 264 micromol/l). Gross hematuria was noted in 72%, hypertension in 64%, and nephrotic syndrome in 48%. Pathologically, except for diffuse crescent formation (a median 65% and range 50-95%), we observed segmental necrosis of glomerular capillaries in 60%, glomerular infiltrating cells in 48%, endothelial cells proliferation in 32%, and rupture of Bowmans' capsule in 24%. Severe tubular interstitial damage was also found, tubular atrophy in 64%, interstitial fibrosis in 60%, diffuse interstitial infiltrating cells in 74%, and interstitial vasculitis in 40%. Immunopathologically, four phenotypes were observed; however, IgA associated with IgM deposition was higher than that in patients with general IgA nephropathy (IgAN). In addition, the infiltrating CD4+, CD8+, CD68+ and PCNA+ cells in renal tissue were significantly high compared with that in controls. In a follow-up study, 66.7% of patients had life-sustaining renal function, 4 of them had normal range of serum creatinine (<124 micromol/l), and only 5 were dialysis-dependent. CONCLUSIONS: The patients with crescentic IgA nephropathy mostly show rapidly progressive nephritis associated with more severe pathological changes including glomerular, tubular interstitial and vascular lesions than in patients with general IgAN. The infiltrates in glomeruli may contribute to the crescentic formation, and the intensive immune suppressing treatment is useful to improve renal damage in patients with DCIgAN.

Adult↗