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Biomedical subjects

L Jiang

Publications and source records attributed to L Jiang.

At least 271 records · Page 15Linked to original sources
PubMed1992

Tumors of the heart. An analysis of 79 cases.

There were 79 cases of cardiac tumors seen from 1957 to July 1988. 49 (62.0%) of them were benign and 30 (38.0%) malignant. All the 49 benign tumors except 2 were surgically excised and found to be myxoma. Of them, 18 patients were male and 31 female. 85.7% of the tumors were located in the left atrium, 12.2% in the right atrium and 2.0% in the left ventricle. Palpitation, dyspnea, chest oppression, fever, episodes of syncope and hemiplegia, cough, diastolic and systolic murmurs at the apical or tricuspid area were the common symptoms and signs. Atrial fibrillation was found only in 2 cases. Echocardiographic findings were diagnostic while ECG and X-ray findings were nonspecific. Four patients died after operation. Of the 30 cases of malignant tumors, 15 were secondary tumors metastasized mainly from the lung or mediastinal malignancies. Of 11 primary tumor cases (7 males and 4 females), 3 were malignant lymphoma, 2 mesothelioma of pericardium, 2 malignant myxoma, 1 angiosarcoma, 1 leiomyosarcoma, 1 fibrosarcoma and 1 rhabdomyosarcoma. Another 4 cases were not studied histopathologically. The clinical manifestations, ECG and X-ray findings of the 11 primary tumors were nonspecific but echocardiography was helpful to the diagnosis. Six patients were operated on and 1 died during hospitalization.

Adolescent↗
PubMed1990

Isolation of a neuropeptide corresponding to the N-terminal 27 residues of the pituitary adenylate cyclase activating polypeptide with 38 residues (PACAP38).

A novel neuropeptide with 38 residues (PACAP38) was isolated from ovine hypothalamic tissues using the pituitary adenylate cyclase activation in rat pituitary cell cultures as a parameter of the biological activity (Miyata et al, Biochem. Biophys. Res. Commun. 164, 567-574, 1989). From the side fractions obtained during the purification of PACAP38, a shorter form peptide with 27 residues corresponding to the N-terminal 27 amino acids of PACAP38 and amidated C-terminus was isolated and named as PACAP27. Synthetic PACAP27 showed a biological activity of adenylate cyclase stimulation comparable to PACAP38. Moreover PACAP27 which shows a considerable homology with vasoactive intestinal polypeptide (VIP) demonstrated a similar vasodepressor activity as VIP, but the adenylate cyclase stimulating activity was about 1000 times greater than VIP.

Adenylyl Cyclases↗
PubMed1990

A novel peptide which stimulates adenylate cyclase: molecular cloning and characterization of the ovine and human cDNAs.

A novel neuropeptide which remarkably stimulates adenylate cyclase in rat anterior pituitary cell cultures has been recently isolated from ovine hypothalami by A. Arimura and his collaborators (Biochem.Biophys.Res.Commun.164, 567-574(1989)). This peptide was designated as PACAP38(Pituitary Adenylate Cyclase Activating Polypeptide with 38 residues). In an attempt to investigate physiological implications of PACAP38, we have succeeded in cloning the cDNAs encoding the precursor of PACAP38 from ovine hypothalamus and human testis. An ovine cDNA encodes a protein of 176 amino acids in which PACAP38 is proceeded by a putative signal peptide and a "pro"-region (107 amino acids), and followed by a Gly-Arg-Arg sequence for proteolytic processing and amidation. Deduced amino-acid sequence of human PACAP38 was completely identical to that of the ovine isolated peptide. Cloning of PACAP38 cDNAs confirms the expression of the corresponding mRNAs and the presence of this neuropeptide in ovine hypothalamus and also in human testis.

Adenylyl Cyclases↗
PubMed1990

[The value of using transesophageal echocardiographic Doppler color flow imaging in patients undergoing cardiac valvular surgery].

To assess the value of intraoperative transesophageal echocardiographical Doppler color flow imaging (TEE-DCFI) during cardiac valvular surgery, 85 consecutive patients with 102 diseased valves for surgery were studied with pre-and post-operative TEE-DCFI. There were 34 women and 51 men with an age range of 15 to 55 years (mean age, 34.91 +/- 9.33 years). The etiology of valve lesion was rheumatic in 57 (AV 10, MV 47), prolapse in 9 (AV 2, MV 7), endocarditis in 21 (AV 12, MV 3, PV 2, prosthetic infection 4), prosthetic dysfunction in 14 (AV 5, MV 9), congenital in 1 (TV). Preoperative TEE-DCFI findings were helpful either in completing with some new information or changing the operation plan in 29 valves (28.43%) including abscess at aortic root in 1, perforation of aortic valve in 2, perforation of mitral valve leaflets in 5 patients with aortic valvular endocarditis, regurgitation or perivalvular leak of prosthetic valve in 4 MVs and 4AVs, left atrial thrombus detected in 8 and excluded in 3 patients with MV disease, small calcified vegetation on PV with normal valve function in 2 patients with congenital heart disease. Postoperative TEE-DCFI evaluation was performed in 53 patients with 70 diseased valves. There was only one mild regurgitation of mitral bioprosthesis and one mild perivalvular leak of aortic prosthesis detected among 40 replaced prosthetic valves. Of 30 valves repaired 23 (77%) valves had trivial or mild residual regurgitation (Group A) and 7 (23%) had moderate residual regurgitation (Group B). Postoperative congestive heart failure was seen in 6 (26.09%) of Group A and 5 (71.43%) of Group B (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

[Influence of processing on trace elements in traditional Chinese drugs].

By comparing the contents of nine trace elements in fourteen Chinese drugs (including thirty-six samples) before and after processing, this experiment was carried out primarily in search of the ways in which bears on trace element contents, so as to help improve the quality of processed drugs.

Drugs, Chinese Herbal↗
PubMed1989

Isolation of a novel 38 residue-hypothalamic polypeptide which stimulates adenylate cyclase in pituitary cells.

A novel neuropeptide which stimulates adenylate cyclase in rat anterior pituitary cell cultures was isolated from ovine hypothalamic tissues. Its amino acid sequence was revealed as: His-Ser-Asp-Gly-Ile-Phe-Thr-Asp-Ser-Tyr-Ser-Arg-Tyr-Arg-Lys-Gln- Met-Ala- Val-Lys-Lys-Tyr-Leu-Ala-Ala-Val-Leu-Gly-Lys-Arg-Tyr-Lys-Gln-Arg-Val-Lys-Asn-Lys - NH2. The N-terminal sequence shows 68% homology with vasoactive intestinal polypeptide (VIP) but its adenylate cyclase stimulating activity was at least 1000 times greater than that of VIP. It increased release of growth hormone (GH), prolactin (PRL), corticotropin (ACTH) and luteinizing hormone (LH) from superfused rat pituitary cells at as small a dose as 10(-10)M (GH, PRL, ACTH) or 10(-9)M (LH). Whether these hypophysiotropic effects are the primary actions of the peptide or what physiological action in the pituitary is linked with the stimulation of adenylate cyclase by this peptide remains to be determined.

Adenylyl Cyclases↗
PubMed1989

[A quantitative study of pulmonary artery systolic pressure in patients with tricuspid regurgitation using continuous wave Doppler].

Pulmonary artery systolic pressure (PASP) was assessed with simultaneous continuous wave Doppler echocardiography (CW) and cardiac catheterization (CATH) in 33 cases. There was a close correlation between CW-estimated peak pressure gradient of tricuspid regurgitation (TRPGp) and CATH-measured PASP (r = 0.96, P less than 0.0001). Excellent correlation (r = 0.96, P less than 0.0001) between CW-estimated PASP and CATH-measured PASP was also obtained. The derived regression equation was PASP = TRPGp + 1.33 kPa. When the patients had relative or pathologic pulmonic stenosis, the regression equation was corrected by pulmonary artery pressure gradient (PAPG). The regression equation became PASP = TRPGp + 1.33-PAPG.

Adolescent↗
PubMed1989

[Quantitative assessment of pulmonary arterial diastolic and mean pressure using continuous wave Doppler].

Continuous wave Doppler echocardiographic study was performed almost simultaneously with right heart catheterization in 24 patients with a variety of cardiovascular disorders and evidence of pulmonary regurgitation detected by pulsed wave Doppler. Their pulmonary arterial diastolic and mean pressure (PADP and PAMP) measured during catheterization were ranging from 5 to 70.6 (mean 30.26 +/- 18) mmHg and from 6.7 to 91.14 (mean 42.41 +/- 23.23) mmHg, respectively. The right ventricular end-diastolic pressure was within normal limit in all but one. The peak, mean and end-diastolic pressure gradients of pulmonary regurgitation (PPRPG, MPRPG and PRPGed) were calculated using simplified Bernoulli Equation and their correlations with PADP and PAMP were analysed using linear regression method. There were close correlations between all PRPGs and PADP or PAMP (r = 0.85 - 0.94, P less than 0.0001). The best equation for assessing PADP was MPRPG + 6 mmHg (r = 0.94, P less than 0.0001), for PAMP was PPRPG + 8 mmHg (r = 0.92, P less than 0.0001). It is evident that those constants in the equations should be adjusted in individual patient who has coexisting right heart failure.

Adolescent↗
PubMed1988

Allergic contact dermatitis to nickel: bioavailability from consumer products and provocation threshold.

Twelve subjects sensitive to nickel underwent patch testing with serial dilutions of nickel sulfate in petrolatum and in water. The provocation threshold (the lowest amount of nickel producing a reaction) varied from 5.2 mg (2.5%) to 0.47 microgram (0.01%) when tested in petrolatum. The provocation threshold was higher with aqueous solutions. The lowest provocation threshold in a statistically significant number of individuals was 1.5 micrograms. Nickel bioavailability from dermatitis-inducing earrings and a necklace was determined by immersing them in plasma, normal saline solution, and synthetic sweat at different pH values over 7 days. Nickel leaching under these conditions exceeded the provocation threshold 1.4- to 93-fold, depending on object and solution. The time course varied with solution. After leaching, surface nickel was measured by the action of dilute nitric acid and total nickel was determined by complete dissolution in aqua regia. Nickel was more bioavailable from earrings than from the necklace, presumably reflecting different metallurgy. Plasma was the most effective solution for removing available nickel from earrings, a possible explanation for the frequent induction of sensitization by ear piercing. Comparison of provocation threshold and leaching results may help determine risks from consumer products.

Adult↗
PubMed1988

A model for the release of adsorbed molecules from the surfaces of airborne particulate matter based on liquid-phase desorption from amorphous carbon blacks.

The release of molecules adsorbed on the surfaces of amorphous carbon blacks has been studied using liquid-solid chromatography. Adsorbate molecules, adsorbents, and mobile phases were selected on the basis of their relevance as models for the release of toxic agents adsorbed on inhalable environmental particulate matter that originates from the incomplete combustion of organic materials. The presence of surface active groups on the carbon blacks has been shown to adsorb and retain adsorbate molecules selectively, and this selectivity can be reduced by competition for these active groups by the displacing solvent. Release is also governed by the surface coverage of the particles and increases as coverage approaches the monolayer.

Adsorption↗