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Biomedical subjects

Jun Ye

Publications and source records attributed to Jun Ye.

At least 55 records · Page 3Linked to original sources
PubMed2004

[A pilot study of selective screening for high risk children with inborn error of metabolism using tandem mass spectrometry in China].

OBJECTIVE: The new technology of tandem mass spectrometry is exerting a significant impact on the diagnostics of inborn metabolic errors, and allows to detect a number of these disorders in a single step. The aim of the present study was to establish a dry blood filter paper method for amino acid and acylcarnitine profiles test using tandem mass spectrometry and to apply the method for selective screening in high risk children with inborn error of metabolism. METHOD: The study group consisted of 104 high risk cases of inborn error of metabolism from 5 pediatric hospitals in Shanghai and Beijing were tested from November 2002 to June 2003; 77 were males and 27 females, the means age was 4.8 +/- 4.2 years. These patients had mental retardation, slow development, psychological abnormalities, muscle hypotonia, jaundice, hepatosplenomegaly, recurrent vomiting, and convulsion. Laboratory examinations suggested metabolic acidosis, hypoglycemia, hyperammonemia and hyperlactacidemia. Phenylketonuria was excluded in this study by routine phenylalanine screening. The control group consisted of 308 children, 170 males and 138 females. The blood was collected on filter paper, punched and extracted into methanol solution with stable isotope labeled internal standards, then derivatized with butanolic-HCl. After preparation, the samples were analyzed by tandem mass spectrometry (API 2000). RESULTS: Ten of 104 patients (9.6%) were positive in our selective screening program, including one with tyrosinemia, one with homocystinuria, one with hyperornithinemia, two with methylmalonic acidemia, one with propionic acidemia, one with 3-hydroxy-3-methylglutaryl-CoA lyase deficiency, two with medium chain acyl-CoA dehydrogenase deficiency, and one with carnitine palmitoyl transferase type II deficiency. CONCLUSION: The authors established a fast, accurate and sensitive tandem mass spectrometry method for amino acid and acylcarnitine profiles analysis, nearly 30 metabolic diseases including amino acid disorders, organic acid disorders and fatty acid oxidation disorders could be detected, most of the diseases that cause death and disability represent preventable entities by early diagnosis and treatment. The results indicated the importance of selective screening for high risk patients with inborn error of metabolism.

Adolescent↗
PubMed2004

[Molecular genetic analysis of congenital lipoid adrenal hyperplasia].

OBJECTIVE: Congenital lipoid adrenal hyperplasia (CLAH) is an autosomal recessive inherited disorder, characterized by deficiency of adrenal and gonadal steroid hormones. Recent studies have shown that mutations in the gene for steroidogenic acute regulatory protein (StAR) cause this most severe genetic disorder in steroid hormone biosynthesis. StAR is a mitochondrial protein promotes cholesterol transfer from outer mitochondrial membrane to the inner mitochondrial membrane, where the cholesterol serves as a substrate for P450scc and initiates steroidogenesis. So far, more than 30 different mutations in the StAR gene have been found in the patients with CLAH from various ethnic groups. None of CLAH patients in the Chinese population has been previously reported. In the present study we analyzed the StAR gene in a Chinese patient with CLAH. METHODS: The patient who was a 19-yr-old phenotypic female, has a 46, XY karyotype. Endocrinological evaluation was performed. Genomic DNA samples were abstracted from the bloods of the patient and his parents. Polymerase chain reaction (PCR), direct DNA sequencing, family analysis and restriction enzyme digestion analysis were used to detect and confirm the mutations of StAR gene. RESULTS: Endocrine evaluation of the patient showed extremely elevated basal concentrations of serum ACTH and gonadotropin and minimal concentration of gonadal steroids. An ACTH stimulation test indicated basal serum dehydroepiandrosterone and 17-hydroxyprogesterone were lower than normal detectable range and had no obvious increase after the ACTH stimulation. Automatic sequencing of 7 exons of the StAR gene with the polymerase chain reaction products of the genomic DNA revealed compound heterozygous for a novel nonsense mutation Q77X in exon 3 and the frameshift mutation 838delA in exon 6. The father carried Q77X mutation and the mother carried 838delA mutation. The restriction enzyme site of the Q77X mutation was examined by endonucleotidase BfaI. Furthermore, this mutation was not found in a series of 20 alleles of normal individuals. CONCLUSION: Q77X is the novel mutation found in the patient with CLAH. Q77X and 838delA compound mutations could inactivate the StAR function and give rise to clinically manifest CLAH. This case is the first Chinese patient with CLAH identified by molecular genetic analysis. DNA-based analysis of StAR gene will be helpful for the diagnosis of CLAH.

Adrenal Hyperplasia, Congenital↗
PubMed2004

[Oxymatrine in the treatment of chronic hepatitis B for one year: a multicenter random double-blind placebo-controlled trial].

OBJECTIVE: To evaluate the efficacy and safety of oxymatrine in the treatment of chronic hepatitis B. METHODS: A multicenter randomized double-blind placebo-controlled trial was conducted. A total of 144 patients with chronic hepatitis B entered the study for 52 weeks; of them 72 received oxymatrine, and 72 received a placebo. Before and after the treatment, clinical symptoms, liver function, serum hepatitis B virus markers, and adverse drug reactions were observed. RESULTS: In 144 patients, 14 were dropped and excluded due to inconsistencies in the included standard. Therefore, the efficacy and safety of 130 patients were analyzed. After being treated for 52 weeks, 70.77% of the patients in the study group had a normal ALT level, and in 43.08% and 33.33% their HBV DNA and HBeAg became negative. In the placebo group, 39.68% had normal ALT level, and 12.31% and 3.33% had their HBV DNA and HBeAg become negative. The rates of complete response and partial response in the oxymatrine group were 23.08% and 58.46%, and in the placebo group they were 3.08% and 44.62%. They were significantly higher in the oxymatrine group than in the placebo group. In the oxymatrine treated patients, 12 weeks after its withdrawal, 60.00% had a normal ALT level, 41.54% and 23.33% had both HBV DNA and HBeAg negative. In the placebo group, 31.75% had a normal ALT level, 3.08% and 1.67% had both HBV DNA and HBeAg negative. The rates of complete response and partial response in the oxymatrine group were 21.54% and 47.69%, and in the placebo group they were 0 and 41.54%. They were significantly higher in the study group than in the placebo group. The adverse reaction rates of oxymatrine in the study and the placebo group were 7.69% and 6.15%, respectively, but there was no statistical significant difference between them. CONCLUSION: Oxymatrine is an effective and safe agent for the treatment of chronic hepatitis B.

Adolescent↗
PubMed2003

Phase space manipulation of cold free radical OH molecules.

We report bunching, slowing, and acceleration of a supersonically cooled beam of diatomic hydroxyl radicals (OH). In situ observation of laser-induced fluorescence along the beam propagation path allows for detailed characterization of longitudinal phase-space manipulation of OH molecules through the Stark effect by precisely sequenced inhomogeneous electric fields.

Journal Article↗
PubMed2003

Orthogonal control of the frequency comb dynamics of a mode-locked laser diode.

We have performed detailed studies on the dynamics of a frequency comb produced by a mode-locked laser diode (MLLD). Orthogonal control of the pulse repetition rate and the pulse-to-pulse carrier-envelope phase slippage is achieved by appropriate combinations of the respective error signals to actuate the diode injection current and the saturable absorber bias voltage. Phase coherence is established between the MLLD at 1550 nm and a 775-nm mode-locked Ti:sapphire laser working as part of an optical atomic clock.

Journal Article↗
PubMed2003

Passively mode-locked glass waveguide laser with 14-fs timing jitter.

Ultralow jitter pulse trains are produced from a passively mode-locked, erbium/ytterbium co-doped, planar waveguide laser by use of high-bandwidth feedback control acting on the physical cavity length and optical pump power. Synchronization of a 750-MHz, fundamentally mode-locked laser to an external clock signal yields an ultralow, root-mean-square relative timing jitter of 14.4 fs integrated from 10 Hz to the Nyquist frequency of 375 MHz.

Journal Article↗
PubMed2003

Picosecond-pulse amplification with an external passive optical cavity.

We experimentally demonstrate the amplification of picosecond pulses at high repetition rates through the coherent addition of successive pulses of a mode-locked pulse train in a high-finesse optical cavity equipped with cavity dumping. Amplification greater than 30 times is obtained at a repetition rate of 253 kHz, boosting the 5.3-nJ pulses from a commercial mode-locked picosecond Ti:sapphire laser to pulse energies of more than 150 nJ.

Equipment Design↗
PubMed2003

Ultralow-jitter, 1550-nm mode-locked semiconductor laser synchronized to a visible optical frequency standard.

Using high-bandwidth feedback, we have synchronized the pulse train from a mode-locked semiconductor laser to an external optical atomic clock signal and achieved what is to our knowledge the lowest timing jitter to date (22 fs, integrated from 1 Hz to 100 MHz) for such devices. The performance is limited by the intrinsic noise of the phase detector used for timing-jitter measurement. We expect such a highly stable device to play an important role in fiber-network-based precise time/frequency distribution.

Journal Article↗
PubMed2003

Intensity-related dynamics of femtosecond frequency combs.

We have performed systematic studies of intensity-related dynamics of the pulse repetition and carrier-envelope offset frequencies in mode-locked Ti:sapphire lasers. We compared the results far two laser systems that have different intracavity dispersion-compensation schemes. We found that the carrier-envelope phase noise and its dynamic response depend critically on the mode-locking conditions. An intensity-related shift of the laser spectrum was found to be instrumental in interpretations.

Journal Article↗
PubMed2003

Single-stage sub-Doppler cooling of alkaline earth atoms.

We report the first experimental study of sub-Doppler cooling in alkaline earth atoms (87Sr) enabled by the presence of nuclear spin-originated magnetic degeneracy in the atomic ground state. Sub-Doppler cooling in a sigma(+)-sigma(-) configuration is achieved despite the presence of multiple, closely spaced excited states. This surprising result is confirmed by an expanded multilevel theory of the radiative cooling force. Detailed investigations of system performance have shed new insights into (sigma(+)-sigma(-)) cooling dynamics and will likely play an important role in the future development of neutral atom-based optical frequency standards.

Journal Article↗
PubMed2003

Flexible and rapidly configurable femtosecond pulse generation in the mid-IR.

We demonstrate a new experimental approach for flexible femtosecond pulse generation in the mid-IR by use of difference-frequency generation from two tightly synchronized Ti:sapphire lasers. The resultant mid-IR pulse train can be easily tuned, with an adjustable repetition frequency up to 100 MHz, a pulse energy of approximately 1.5 x 10(-13) J, and an intensity noise similar to that of the Ti:sapphire. Rapid switching of the mid-IR wavelength and programmable amplitude modulation are achieved by precision setting of the time delay between two original pulses.

Journal Article↗
PubMed2003

Induction of apoptosis of articular chondrocytes and suppression of articular cartilage proteoglycan synthesis by heat shock.

We investigated cellular and matrix responses of articular cartilage to heat shock. Rat articular cartilage was pretreated at 37 degrees C for 24 h before being exposed to 48 degrees C for 10 min and subsequently incubated at 37 degrees C for 1, 2, 4, 7, 10, and 14 days. Following heat shock, a terminal deoxynucleotidyl transferase nick end labeling assay showed that articular chondrocyte apoptosis appeared at day 1, peaked at day 7, and declined by day 14. Analysis by transmission electron microscopy confirmed that the chondrocytes had characteristic morphological features of apoptosis; immunohistochemical staining revealed that caspase-3 activity in chondrocytes increased, 3-B-3-positive articular chondrocytes decreased in number, and the expression of 3-B-3 native epitope in articular chondrocytes was reduced. Safranin-O staining revealed that depletion of proteoglycans in the matrix was not found in any group. Morphological and biochemical evidence from this study suggested that heat shock at 48 degrees C induced articular chondrocyte apoptosis and suppressed proteoglycan synthesis of articular cartilage in vitro. This study thus provides evidence of the onset of osteoarthritis induced by heat shock and a basis for choosing a temperature at which malignant bone tumor cells can be killed with minimal damage to articular cartilage.

Animals↗
PubMed2003

[Multicenter clinical study about the action of Fuzheng Huayu Capsule against liver fibrosis with chronic hepatitis B].

OBJECTIVE: To study the efficacy and safety of Fuzheng Huayu Capsule (FZHY Capsule) against liver fibrosis with chronic hepatitis B. METHODS: Multicentric, randomized, double blinded and paralleled control led trial was conducted on patients (aged between 18 and 65) with liver fibrosis in chronic hepatitis B Indexes observed: (1) hepatic histological changes and HBV markers were observed at 0 and 24th week during the treatment; serological indexes (HA, LN, P-III-P, IV-C) were determined and B ultrasound examination of spleen and liver was taken at 0, 12th, 24th week; liver function (during the period of follow-up, liver function and serological indexes for liver fibrosis were evaluated) were observed at 0, 6th, 12th, 18th, 24th week; (2) indexes for safety: blood and urine routine tests, renal function and ECG were examined. RESULTS: (1) Enrollment and demographic data: There was no significant difference between the trial (110 cases) and control group (106 cases) in demographic feature, vital signs, course of illness, history for drug anaphylaxis, history of previous therapy, liver function, serological indexes for liver fibrosis, liver histological examination (99 cases for test group, 96 cases for control group), HBV markers, and renal function, etc. (2) Histological pathological examination: 93 cases of liver histological examination were taken, of these 50 cases for the trial group and 43 cases for control group which turned out to be at S mean value of 2.33 and 2.11 respectively pretreatment according to criteria for liver fibrosis staging. Post-treatment, the trial showed a significant decrease with S value of 1.80 compared to that of pretreatment; however, there was no significant improvement in control group before and after the treatment with S mean value of 2.14. There was significant difference in reversing rate (decrease at least 1 stage according to criteria for liver fibrosis staging) between the trial (52%) and control (23.3%) after liver biopsy. The trial had a rather good effect on improving inflammatory activity and was superior to control group with a marked decrease of mean value of inflammatory activity and score of inflammation (P<0.05). (3)Serological indexes for liver fibrosis: There was a significant decrease in HA, LN, P-III-P, IV-C content in test group after 12 and 24 weeks' treatment compared to that of pretreatment; the differences of HA, LN, P-III-P, IV-C between 12, 24 weeks' treatment and pretreatment were significantly greater than control group (P<0.01 or 0.05); the effectual was defined as 2 of 4 indexes lowered more than 30% of the baseline, according to this criteria, the trial was 72.7%, while control group 27.4% (P<0.01). (4)Liver function: Obvious improvement of serum Alb, ALT, AST, GGT was seen in 2 groups; compared with control group, marked improvement of GGT and Alb in the trial (P<0.05); the effective rate of serum ALT in the trial group was 72.7%, while control 59.4%. (5)No changes of significant difference between pre- and post-treatment in routine tests for blood and urine, renal function and ECG, etc. There was also no difference in the stable rate of ALT and serological indexes for liver fibrosis between the trial and control group 12 weeks after withdrawal (P<0.05). CONCLUSION: Fuzheng Huayu Capsule has good effect on alleviating liver fibrosis in chronic hepatitis B without any adverse effect and is superior to Heluo Shugan Capsule. Fuzheng Huayu Capsule is a safe and effective medicine for the treatment of liver fibrosis in chronic hepatitis B.

Adult↗
PubMed2003

Oxymatrine therapy for chronic hepatitis B: a randomized double-blind and placebo-controlled multi-center trial.

AIM: To evaluate the efficacy and safety of capsule oxymatrine in the treatment of chronic hepatitis B. METHODS: A randomised double-blind and placebo-controlled multicenter trial was conducted. Injection of oxymatrine was used as positive-control drug. A total of 216 patients with chronic hepatitis B entered the study for 24 weeks, of them 108 received capsule oxymatrine, 36 received injection of oxymatrine, and 72 received placebo. After and before the treatment, clinical symptoms, liver function, serum hepatitis B virus markers, and adverse drug reaction were observed. RESULTS: Among the 216 patients, six were dropped off, and 11 inconsistent with the standard were excluded. Therefore, the efficacy and safety of oxymatrine in patients were analysed. In the capsule treated patients, 76.47% became normal in ALT level, 38.61% and 31.91% became negative both in HBV DNA and in HBeAg. In the injection treated patients, 83.33% became normal in ALT level, 43.33% and 39.29% became negative both in HBV DNA and in HBeAg. In the placebo treated patients, 40.00% became normal in ALT level, 7.46% and 6.45% became negative both in HBV DNA and in HBeAg. The rates of complete response and partial response were 24.51% and 57.84% in the capsule treated patients, and 33.33% and 50.00% in the injection treated patients, and 2.99% and 41.79% in the placebo treated patients, respectively. There was no significance between the two groups of patients, but both were significantly higher than the placebo. The adverse drug reaction rates of the capsule, injection and placebo were 7.77%, 6.67% and 8.82%, respectively. There was no statistically significant difference among them. CONCLUSION: Oxymatrine is an effective and safe agent for the treatment of chronic hepatitis B.

Administration, Oral↗
PubMed2003

Grading and staging of hepatic fibrosis, and its relationship with noninvasive diagnostic parameters.

AIM: To explore the grade and stage of pathology and the relationship between grading and staging of hepatic fibrosis and noninvasive diagnostic parameters. METHODS: Inflammatory activity and fibrosis of consecutive liver biopsies from 200 patients with chronic liver disease were determined according to the Diagnostic Criteria of Chronic Hepatitis in China, 1995. A comparative analysis was made in these patients comparing serum markers, Doppler ultrasonography, CT and/or MR imaging with the findings of liver biopsy. RESULTS: With increase of inflammatory activity, the degree of fibrosis also rose. There was a close correlation between liver fibrosis and inflammatory activity. AST, GGT, albumin, albumin/globulin, ALP, AFP, hyaluronic acid, N-terminal procollagen III(P III NP), collagen type IV(Col IV), tissue inhibitors of metalloproteinases-1 (TIMP-1), alpha-2-macroglobulin, natural killer cells(NK), some parameters of Doppler ultrasonography, CT and/or MR imaging were all related to the degree of inflammatory activity. GGT, albumin, albumin/globulin, ALP, AFP, hyaluronic acid, Col IV, TIMP-1, alpha-2- macroglobulin, transforming growth factor-beta 1 (TGFbeta1), NK, some parameters of Doppler ultrasonography, CT and/or MR imaging were all related to the staging of fibrosis. By regression analysis, the parameters used in combination to differentiate the presence or absence of fibrosis were age, GGT, the parameter of blood flow of portal vein per minute, the maximum oblique diameter of right liver by B ultrasound, the wavy hepatic surface contour by CT and/or MR. The sensitivity, specificity and accuracy of the above parameters were 80.36%, 86.67%, and 81.10%, respectively. CONCLUSION: There is close correlation between liver fibrosis and inflammatory activity. The grading and staging of liver fibrosis are related to serum markers, Doppler ultrasonography, CT and/or MR imaging. The combination of the above mentioned noninvasive parameters are quite sensitive and specific in the diagnosis of hepatic fibrosis.

Adolescent↗
PubMed2003

Relationship between clinical and pathologic findings in patients with chronic liver diseases.

AIM: To explore the relationship between clinical findings of patients with chronic liver diseases and the pathologic grading and staging of liver tissues. METHODS: The inflammatory activity and fibrosis of consecutive liver biopsies from 200 patients were determined according to the diagnosis criteria of chronic hepatitis in China established in 1995. A comparative analysis was carried out for 200 patients with chronic liver diseases by comparing their clinical manifestations, serum biochemical markers with the grading and staging of liver tissues. RESULTS: It was revealed that age, index of clinical symptoms and physical signs were obviously relevant to the pathologic grading and staging of liver tissues (P<0.05). Blood platelet, red blood cells, aspartate aminotransferase (AST), N-terminal procollagen III (PIII NP) were apparently correlated with the degree of inflammation. PGA (prothrombin time, GGT, apoprotein A1) index, PGAA (PGA+delta2-macroglobulin) index, albumin and albumin/globulin were relevant to both inflammation and fibrosis. Hyaluronic acid (HA) was an accurate variable for the severity of hepatic inflammation and fibrosis. The combination of serum markers for fibrosis could increase the diagnostic accuracy. It was notable that viral replication markers were not relevant to the degree of inflammation and fibrosis. CONCLUSION: There is a good correlation between clinical findings and the pathologic grading and staging of liver tissues, which may give aid to the noninvasive diagnosis of liver fibrosis.

Chronic Disease↗
PubMed2002

Screening for tetrahydrobiopterin deficiency among hyperphenylalaninemia patients in Southern China.

OBJECTIVES: To assess the incidence of tetrahydrobiopterin (BH4) deficiency among patients with hyperphenylalaninemia (HPA) in southern Chinese and evaluate clinical outcome and gene mutations in tetrahydrobiopterin deficient patients. METHODS: Urinary neopterin (N) and biopterin (B) was analyzed in 87 patients with hyperphenylalaninemia by high-performance liquid chromatography. Further combined loading tests with phenylalanine (Phe) (100 mg/kg) and tetrahydrobiopterin (BH4) (7.5 mg/kg) were performed in suspected patients with abnormal urinary pterin profiles. Gene mutation analysis was performed for patients with BH4 deficiency and their parents. BH4 deficient patients were treated with BH4 and neurotransmitter precursors after diagnosis. Blood phenylalanine levels, clinical symptoms and mental development were followed up. RESULTS: Eleven patients were diagnosed as having BH4 deficiency caused by 6-pyruvoyl tetrahydropterin synthase (PTPS) deficiency. The incidence of tetrahydrobiopterin (BH4) deficiency among patients with hyperphenylalaninemia (HPA) in southern Chinese was 10%. Combined loading tests with phenylalanine and oral BH4 were done in 4 of 11 patients and their phenylalanine levels were decreased to normal 4 - 6h after BH4 administration. Four different mutations (P87S, N52S, D96N and G144R) in the PTPS gene were detected in 5 families. Five PTPS-deficient patients were treated with synthetic BH4, neurotransmitter precursors (L-dopa plus carbidopa, and 5-hydroxytryptophan). They had satisfactory physical and mental development after treatment. One patient with partial PTPS deficiency had normal growth and mental development without treatment. CONCLUSIONS: Our results emphasize that screening for BH4 deficiency should be carried out in all patients with hyperphenylalaninemia in order to minimize the misdiagnosis. Patients with BH4 deficiency should be treated early with BH4 and a combination of neurotransmitter precursors.

Biopterins↗