Biomedical subjects

Q Jia

Publications and source records attributed to Q Jia.

At least 19 recordsLinked to original sources

PubMed2001

Quantification of urine 17-ketosteroid sulfates and glucuronides by high-performance liquid chromatography-ion trap mass spectroscopy.

The measurement of androgen steroids has been utilized as a clinical indicator of adrenal function, androgen abuse, and as a prediction of general health or biological aging. An improved high-performance liquid chromatography-ion trap mass spectroscopic method with sonic spray ionization (SSI) technology for the quantification of individual urinary 17-ketosteroid sulfates and glucuronides was developed and validated. Sample preparation was simplified using a C18 cartridge followed by direct injection onto a reversed-phase HPLC column. Individual 17-ketosteroid from 63 urinary specimens collected in a 24-h period was measured. 17-Ketosteroid conjugates, total 17-KS-S and the ratio of total 17-KS-S to creatinine referred to herein as the Anabolic/Catabolic Index (ACI) showed statistically significant negative correlations with age.

Adult↗

PubMed2001

Molecular genetic analysis of revertants from a poliovirus mutant that is specifically adapted to the mouse spinal cord.

SA virus, a mutant of the Mahoney strain of type 1 poliovirus (PV1/Mahoney), replicates specifically in the spinal cords of mice and causes paralysis, although the PV1/Mahoney strain does not show any mouse neurovirulence (Q. Jia, S. Ohka, K. Iwasaki, K. Tohyama, and A. Nomoto, J. Virol. 73:6041-6047, 1999). The key mutation site for the mouse neurovirulence of SA was mapped to nucleotide (nt) 928 of the genome (A to G), resulting in the amino acid substitution of Met for Ile at residue 62 within the capsid protein VP4 (VP4062). A small-plaque phenotype of SA appears to be indicative of its mouse-neurovirulent phenotype. To identify additional amino acid residues involved in the host range determination of PV, a total of 14 large-plaque (LP) variants were isolated from a single point mutant, Mah/I4062M, that showed the SA phenotype. All the LP variants no longer showed any mouse neurovirulence when delivered via an intraspinal inoculation route. Of these, 11 isolates had a back mutation at nt 928 (G to A) that restored the nucleotide of the PV1/Mahoney type. The reversions of the remaining three isolates (LP8, LP9, and LP14) were mediated by a second site mutation. Molecular genetic analysis involving recombinants between Mah/I4062M and the LP variants revealed that the mere substitution of an amino acid residue at position 107 in VP1 (Val to Leu) (LP9), position 33 in VP2 (Val to Ile) (LP14), or position 231 in VP3 (Ile to Thr) (LP8) was sufficient to restore the PV1/Mahoney phenotype. These amino acid residues are located either on the surface or inside of the virus particle. Our results indicate that the mouse neurovirulence of PV is determined by the virion surface structure, which is formed by all four capsid proteins.

Adaptation, Physiological↗

PubMed2001

Stereotactic radiosurgery for primary trigeminal neuralgia using the Leksell Gamma unit.

OBJECTIVE: Previous papers have reported Gamma Knife radiosurgery to be a safe, effective method for primary trigeminal neuralgia. Since November 1996, we have treated primary trigeminal neuralgia using the Leksell Gamma Knife at the Tianjin Medical University. The present study reports clinical results of Gamma Knife radiosurgery in the treatment of trigeminal neuralgia in 80 cases. METHODS: The mean patient age was 67 years (range 32-92), the mean duration of facial pain was 7.6 years (range 1.5-29). The male:female ratio was 31:49. The right side of the face was involved in 45 patients (56.25%) and the left side in 30 cases (37.5%), with bilateral involvement in 5 cases (6.25%). Under local anesthesia, all patients underwent stereotactic MRI to identify the trigeminal nerve. A single isocenter, using a 4-mm collimator, was positioned at the sensory root of the trigeminal nerve entry zone of the pons, 4-6 mm from the brainstem surface, so that no more than the 20% isodose was administered to the brainstem. The maximum dose was between 70 and 90 Gy, with a mean of 75.6 Gy. For bilateral trigeminal neuralgia, two separate matrices were employed, and bilateral Gamma Knife radiosurgery was performed on the same day. RESULTS: Follow-up ranged from 12 to 43 months (mean 23.7 months). Neurological evaluation indicated excellent response in 42 cases (52.5%), good response in 25 cases (31.25%), effective response in 8 cases (10%), so the total pain control rate was 93.75%. The latency from Gamma Knife surgery to pain relief ranged from 1 to 120 days (mean 22 days). Among the 75 patients 7 with pain control experienced pain recurrence 5-26 months after being completely free from pain. A second Gamma Knife radiosurgery was performed in 7 recurrent cases and 5 patients with treatment failure. A maximal dose ranging from 70 to 80 Gy was given (mean 74.2 Gy). After a mean follow-up of 18 months (8-33 months), 9 patients achieved excellent results, and 2 had good results. The latency interval to pain relief ranged from 1 to 120 days (mean 15 days). Nine patients developed new facial numbness, while no other complication appeared in the remainder of the patients. CONCLUSIONS: Gamma Knife radiosurgery is a safe and effective method in the treatment of trigeminal neuralgia once diagnosis is established.

Adult↗

PubMed2001

[The effect of salvia miltiorrhiza and shengmai on inflammatory mediator and renal function of post-operative patients with obstructive jaundice].

OBJECTIVE: To investigate the effect of salvia miltiorrhiza and shengmai (SS) on inflammatory mediator and renal function in patients with obstructive jaundice (OJ). METHODS: This study included three groups: the OJ patients receiving SS for 6 days after operation (the SS group, n = 15); the OJ patients not receiving SS (the OJ group, n = 15); the patients with other hepato-biliary disorders (the Non-OJ group, n = 15). The levels of ET, LPs, TNF-alpha, IL-6, IL-8 and urine RBP, TFR, ALB were measured one day before operation and 1, 4, 7 days after operation. RESULTS: The SS group's LPs, TNF-alpha, IL-6, IL-8, ET, RBP, TFR and ALB levels were obviously lower on Day 7 after operation as compared with those on Day 1 after operation (P < 0.05). The urine RBP and ALB levels were significantly lower in the SS group than in the OJ group (P < 0.05). CONCLUSION: The post-operative use of salvia miltiorrhiza and shengmai for patients with obstructive jaundice may effectively decrease the postoperative levels of plasma LPs, ET, TNF-alpha, IL-6 and IL-8. At the same time, salvia miltiorrhiza and shengmai may protect renal function by inhibiting inflammatory mediator and improving blood dynamics.

Adult↗

PubMed2001

[Characteristics in frequency domain by inductively coupled plasma atomic emission spectrometry with charge injection detection].

The characteristics of two-dimension spectra obtained by inductively coupled plasma atomic emission spectrometry (ICP-AES) with charge injection detection (CID) in frequency domain were studied in the present paper. The measurement spectra were Fourier transformed and the frequency distribution of the spectra was obtained. Results showed that the spectra in frequency domain could be divided into two parts: high frequency and low frequency signals. The later stood for measurement spectra and the former for background and noises. However, the high frequency signals could not be smoothed simply to reduce noises because the background was deteriorated even though the spectral signal did not change significantly.

Mass Spectrometry↗

PubMed2000

Modified Aloe barbadensis polysaccharide with immunoregulatory activity.

Aloe barbadensis polysaccharide was partially digested with cellulase and further purified by dialysis, stepwise ethanol precipitation, and size exclusion chromatography. Crude modified Aloe polysaccharide (MAP) activated macrophage cells and stimulated fibroblast growth. Under the same conditions, native Aloe barbadensis gel had no effect on macrophage activation. MAP prevented ultraviolet B (UVB) irradiation-induced immune suppression as determined by contact hypersensitivity (CHS) response in C3H/HeN mice. This in vivo activity was correlated with the activity of MAP to inhibit UVB irradiation-induced tumor necrosis factor alpha (TNF-alpha) release from human epidermoid carcinoma cells (KB cells). MAP with an average molecular weight of 80,000 Dalton (Da) contained mannose, galactose, and glucose in a ratio of 40:1.4:1.0. MAP was likely a linear, highly acetylated molecule.

Adjuvants, Immunologic↗

PubMed2000

[Prediction and evaluation of heterosis of beef cattle and their application].

The genetic structure and genetic variation of eight beef cattle cross parents populations were analyzed by six microsatellite loci, and heterosis of beef cattle was predicted. On the basis of microsatellite analysis, the effect of 18 cross combinations was estimated by the method of individual animal model BLUP. A new method of molecular quantitative genetics that select best of all cross combination was submitted. The results showed that the combinations with Hereford Limousine and Charolais as paternal parent are better than others in Fengning and Longhua regions; the combinations with Limousine Angus and Hereford as paternal parent are better than others in Zanhuang regions; the combinations with Hereford Limousine and Piemontese as paternal parent are better than others in Funing regions. Effect of three breeds cross is better than two breeds.

Animals↗

PubMed2000

[Clinical effect of Xinqingning combined low dose continuous gastrointestinal dialysis in treating uremia].

OBJECTIVE: To investigate the clinical effect of Xinqingning (XQN), a preparation of rhubarb, combined with low dose continuous gastrointestinal dialysis in treating uremia. METHODS: Patients of uremia were divided into three groups at random, eighteen patients in the group A were treated with 1000 ml gastrointestinal dialysate (non-absorbed mannitol solution) orally 2-3 times a day, twenty patients in the group B treated with the same therapy as that in the group A, but combined with XQN 5-10 tablets 3 times per day and 19 patients in the group C treated by orally taken coated aldehyde oxystarch 5-10 g, 3 times a day. The therapeutic course for the three groups were 11 months. The changes in clinical manifestation, renal function, nutritional condition, and electrolytes before and after treatment were observed. RESULTS: After treatment, significant improvement was revealed in aspects of uremic symptoms, quality of life, nutritional condition, serum creatinine, urea nitrogen, serum phosphate, uric acid, CO2 combining power, creatine clearance, body weight and arm muscular circumference in the group A and B, as compared with those in the group C. In comparison of the group A and B, the group B showed a lower serum triglyceride and slower progression of chronic renal failure (CRF). All the criteria were not improved in the group C and with serum creatinine raised significantly. CONCLUSION: XQN combined low dose continuous gastrointestinal dialysis therapy was effective in definitely treating uremia, it provides a new therapeutic means of non-replacement therapy for CRF with uremia.

Adult↗

PubMed2000

[Modern spectral estimation of ICP-AES].

The inductively coupled plasma atomic emission spectrometry (ICP-AES) and its signal characteristics were discussed using modern spectral estimation technique. The power spectra density (PSD) was calculated using the auto-regression (AR) model of modern spectra estimation. The Levinson-Durbin recursion method was used to estimate the model parameters which were used for the PSD computation. The results obtained with actual ICP-AES spectra and measurements showed that the spectral estimation technique was helpful for the better understanding about spectral composition and signal characteristics.

Regression Analysis↗

PubMed1999

Structure-activity relationships: analogues of the dicaffeoylquinic and dicaffeoyltartaric acids as potent inhibitors of human immunodeficiency virus type 1 integrase and replication.

The dicaffeoylquinic acids (DCQAs) and dicaffeoyltartaric acids (DCTAs) are potent and selective inhibitors of human immunodeficiency virus type 1 (HIV-1) integrase. They also inhibit HIV-1 replication at nontoxic concentrations. Since integrase is an excellent target for anti-HIV therapy, structure-activity relationships were employed to synthesize compounds with: (1) improved potency against HIV-1 integrase, (2) improved anti-HIV effect in tissue culture, and (3) increased selectivity as indicated by low cellular toxicity. Thirty-four analogues of the DCTAs and DCQAs were synthesized and tested for cell toxicity, anti-HIV activity, and inhibition of HIV-1 integrase. Seventeen of the 34 analogues had potent activity against HIV-1 integrase ranging from 0. 07 to >10 microM. Seventeen analogues that were synthesized or purchased had no inhibitory activity against integrase at concentrations of 25 microM. Of the biologically active analogues, 7 of the 17 inhibited HIV replication at nontoxic concentrations. The most potent compounds were D-chicoric acid, meso-chicoric acid, bis(3,4-dihydroxydihydrocinnamoyl)-L-tartaric acid, digalloyl-L-tartaric acid, bis(3,4-dihydroxybenzoyl)-L-tartaric acid, dicaffeoylglyceric acid, and bis(3, 4-dihydroxyphenylacetyl)-L-tartaric acid. Anti-HIV activity of the active compounds in tissue culture ranged from 35 to 0.66 microM. Structure-activity relationships demonstrated that biscatechol moieties were absolutely required for inhibition of integrase, while at least one free carboxyl group was required for anti-HIV activity. These data demonstrate that analogues of the DCTAs and the DCQAs can be synthesized which have improved activity against HIV integrase.

Anti-HIV Agents↗

PubMed1999

Clinical study of orthokeratology in young myopic adolescents.

This project was designed to study the efficacy of orthokeratology and its related problems in a population of young myopic adolescents. Fifty-four young myopia adolescents ages 11 to 15 years were enrolled in the study and followed over a 6-month period. The procedures included (1) baseline refraction, assessment of tear quality and quantity, and cornea examination including cornea topography, A-scan ultrasound of cornea thickness, and spectromicroscopy of the corneal endothelium; (2) diagnostic lens fitting and evaluation; (3) lens dispensing and educating the patients or their parents; (4) follow-up schedule and data analysis; and (5) maintenance lens dispensing and analysis of wearing schedules. Myopia was reduced between -1.25 and -5.00 D (-3.00 D average). Myopia reduction was almost complete in the first 6 months, with most of the reduction occurring during the first 2 weeks. Seventy-five percent of the possible reduction occurred during this 2-week time period. Tear quality and quantity influenced reduction speed and amount. Corneal thickness and endothelium remained unchanged over the study period. Subjective refraction is the most reliable method to measure the status of ocular refractive changes. Corneal staining occurred in 45% of subjects during the procedure, mainly in subjects with tear problems. Eighteen percent of the subjects showed induced astigmatism, which could be reversed by refitting the lens or changing the wearing schedule. Maintenance lenses had to be worn every night for young adolescents to maintain myopia reduction. Orthokeratology is a reliable option for reducing some myopia in young adolescents. The first 2 weeks are critical for the procedure. Complete examination and the data analysis procedures are important for monitoring prognosis and eye health.

Journal Article↗

PubMed1999

Pikuroside: a novel iridoid from Picrorhiza kurroa.

A new iridoid, pikuroside (1), was isolated from the roots of Picrorhiza kurroa, together with three known iridoids, picroside I (2), picroside II (3), and 6-feruloyl catalpol (4). The structure of 1 was established by interpretation and full assignments of NMR spectral data. Pikuroside (1) had no antiinflammatory activity, although the crude extract and picroside II (3) demonstrated moderate activity.

Animals↗

PubMed1999

Isolation and molecular characterization of a poliovirus type 1 mutant that replicates in the spinal cords of mice.

The Mahoney strain of poliovirus type 1 (OM) is generally unable to cause paralysis in mice. We isolated a mouse-adapted mutant, PV1/OM-SA (SA), from the spinal cord of a mouse that had been intracerebrally inoculated with OM. SA showed mouse neurovirulence only with intraspinal inoculation, and the infected mice developed a flaccid paralysis, which was indistinguishable from that observed in poliovirus-sensitive transgenic mice inoculated with OM. SA antigens were detected in neurons of the spinal cords of the infected mice. Nucleotide (nt) sequence analysis revealed 9 nt changes on the SA genome, resulting in three amino acid (a.a.) substitutions, i.e., one each in the capsid proteins VP4 and VP1 and in the noncapsid protein 2C. To identify the key mutation site(s) for the mouse neurovirulence, virus recombinants between OM and SA were constructed by using infectious cDNA clones of these two viruses and tested for their mouse neurovirulence after inoculation via an intraspinal route. The results indicated that a mutation at nt 928 (replacement of A with G), resulting in a substitution of Met for Ile at a.a. 62 within VP4, was responsible for conferring the mouse neurovirulence phenotype of the mutant SA. The mutation in VP4 may render the virus accessible to a molecule that acts as a virus receptor and is located on the surfaces of neurons of the mouse spinal cord. This molecule appears not to be expressed in the mouse brain.

Adaptation, Physiological↗

PubMed1999

[Influence of different total parenteral nutrition support upon hepatic regeneration after partial hepatectomy in rats].

This study was designed to investigate the effects of different TPN on liver regeneration after partial hepatectomy in rats. Forty Wistar rats were randomly divided into four groups. Groups A and B (normal rats) received BCAA-enriched TPN (45% BCAAs) and standard TPN (24% BCAAs) respectively after 34% hepatectomy; Groups C and D (rats with cirrhosis of liver) received the same TPN as Groups A and B received respectively after 34% hepatectomy. On the third day after operation, all rats were killed and specimens of liver and blood were taken for measurement of activity of liver regeneration. The results showed that DNA synthesis rate and mitosis rate in Groups A and B were significantly greater than those in Groups C and D respectively; RLR, DNA synthesis rate and mitosis rate in Groups A and C were significantly higher than those in Groups B and D respectively. These suggest that the effect of the same TPN on liver regeneration in normal rats is better than that in cirrhosis rats and that BCAA-enriched TPN can provide more excellent supplementation than standard TPN can do either in normal liver or cirrhosis liver after partial hepatectomy.

Animals↗

PubMed1998

[Effects of fat emulsion on serum lipid, apo A I, apo B100, LCAT, KBR of postoperative patients with liver disorder].

Twenty post-operative patients with liver disorder were divided randomly into two groups. Ten of them received mean 0.82 g.kg-1.d-1 fat emulsion(42% of the total calorie), and the other ten received mean 1.72 g.kg-1.d-1 fat emulsion (52% of the total calorie) via vein during 5 post-operative days. Their serum lipid, apoA I, apoB100, ketone body ratio (KBR), fat clearance, LCAT and so on were investigted. The results suggest that it is safe for liver-disordered patients with slight or even moderate abnormality of liver function to receive mean 0.82 g.kg-1.d-1 and 1.72 g.kg-1.d-1 fat emulsion after operation and the use of mean 1.72 g.kg-1.d-1 fat emulsion will do no harm but good to liver function.

Adult↗

PubMed1998

[Intracardiac operations performed in beating heart through mini-thoracotomy in 34 patients].

OBJECTIVE: To introduce the technique of intracardiac operations performed in beating heart through mini-thoracotomy. METHOD: >From March 1995 to June 1997, intracardiac operations were performed in beating heart through right subaxillary anterolateral mini-thoracotomy with normothermic extracorporeal circulation in 34 patients. 16 patients had atrial septal defect, 14 ventricular septal defect, 2 mitral insufficiency, 1 right coronary artery-right ventricular fistula, and 1 Ebstein's anomaly. RESULT: The mean cardiopulmonary bypass time was 22.54 minutes. There were no embolism, arrhythmia and cerebral complications. Postoperative hospital stay was 8.0 +/- 2.2 days. All the patients had no heart murmur and residual shunt, and enjoyed a full range of physical activities in a follow-up of 2 to 26 months. CONCLUSION: Intracardiac operations performed in beating heart through right subaxillary anterolateral mini-thoracotomy appears to be less invasive, simple, safe and cosmetic.

Adolescent↗

PubMed1997

[Cardiac operation via subaxillary and anterolateral subaxillary thoracotomy with cardiopulmonary bypass].

From March 1995 to August 1996, 50 patients underwent cardiac operation through subaxillary and anterolateral subaxillary thoracotomy with cardiopulmonary bypass. 17 had atrial septal defect, 26 ventricular septal defect, 3 mitral stenosis and insufficiency, 1 isolated mitral insufficiency, 1 double chamber of right ventricle, 1 partial common atrioventricular canal, and 1 cor atriatriatum. All operations were successfully performed without technical difficulty. The cardiopulmonary bypass time was 40.19 +/- 17.17 minutes with aortic cross-clamping time of 22.59 +/- 11.06 minutes. There were no operative death and complications. In conclusion, the subaxillary and anterolateral subaxillary thoracotomy incision appears to be a minimally invasive, safe, effective and cosmetic alterative to median sternotomy for cardiac operation.

Adolescent↗

PubMed1996

Inhibitors of HIV-1 replication [corrected; erratum to be published] that inhibit HIV integrase.

HIV-1 replication depends on the viral enzyme integrase that mediates integration of a DNA copy of the virus into the host cell genome. This enzyme represents a novel target to which antiviral agents might be directed. Three compounds, 3,5-dicaffeoylquinic acid, 1-methoxyoxalyl-3,5-dicaffeoylquinic acid, and L-chicoric acid, inhibit HIV-1 integrase in biochemical assays at concentrations ranging from 0.06-0.66 microgram/ml; furthermore, these compounds inhibit HIV-1 replication in tissue culture at 1-4 microgram/ml. The toxic concentrations of these compounds are fully 100-fold greater than their antiviral concentrations. These compounds represent a potentially important new class of antiviral agents that may contribute to our understanding of the molecular mechanisms of viral integration. Thus, the dicaffeoylquinic acids are promising leads to new anti-HIV therapeutics and offer a significant advance in the search for new HIV enzyme targets as they are both specific for HIV-1 integrase and active against HIV-1 in tissue culture.

Antiviral Agents↗