Biomedical subjects

G Z He

Publications and source records attributed to G Z He.

18 recordsLinked to original sources

PubMed2004

Vacuum ultraviolet pulsed field ionization study of ND3: accurate thermochemistry for the ND2-ND2+ and ND3-ND3+ system.

The dissociation of energy-selected ND(3) (+) to form ND(2) (+)+D near its threshold has been investigated using the pulsed field ionization-photoelectron (PFI-PE)-photoion coincidence method. The breakdown curves for ND(3) (+) and ND(2) (+) give a value of 15.891+/-0.001 eV for the 0 K dissociation threshold or appearance energy (AE) for ND(2) (+) from ND(3). We have also measured the PFI-PE vibrational bands for ND(3) (+)(X;v(2) (+)=0, 1, 2, and 3), revealing partially resolved rotational structures. The simulation of these bands yields precise ionization energies (IEs) for ND(3) (+) X(0,v(2) (+)=0-3,0,0)<--ND(3) X(0,0,0,0). Using the 0 K AE (ND(2) (+)) and IE(ND(3))=10.200+/-0.001 eV determined in the present study, together with the known 0 K bond dissociation energy for ND(3) [D(0)(D-ND(2))=4.7126+/-0.0025 eV], we have determined the D(0)(ND(2) (+)-D), IE(ND(2)), and 0 K heat of formation for ND(2) (+) to be 5.691+/-0.001 eV, 11.1784+/-0.0025 eV, and 1261.82+/-0.4 kJ/mol, respectively. The PFI-PE spectrum is found to exhibit a steplike feature near the AE(ND(2) (+)), indicating that the dissociation of excited ND(3) (+) at energies slightly above the dissociation threshold is prompt, occurring in the time scale </=10(-7) s, as observed for the NH(3) system. The available energetic data for the NH(2)-NH(2) (+) and NH(3)-NH(3) (+) system are found to be in excellent accord with those for the ND(2)-ND(2) (+) and ND(3)-ND(3) (+) system after taking into account the zero-point vibrational energy corrections. This finding indicates that the thermochemical data for these two systems are reliable with well-founded error limits.

Journal Article↗

PubMed2000

[Research of compound cyclosporin A mouthwash in the treatment of oral lichen planus].

Thirty patients of oral lichen planus(OLP) were treated with compound CyA mouthwash, while the control group was treated with KouTai. The results showed that the rate of success and total rate of success of patients treated with compound CyA mouthwash were 63 percent and 97 percent respectively, but those of the control group treated with kouTai were 10 percent and 63 percent respectively. There was a statistically significant difference(P < 0.01). No side-effects were found. The mouthwash is an effective, safe and local drug used in the treatment of OLP.

Adolescent↗

PubMed2000

The pharmacokinetics and tolerability of the oral neuraminidase inhibitor oseltamivir (Ro 64-0796/GS4104) in healthy adult and elderly volunteers.

The tolerability and pharmacokinetics of Ro 64-0802, a potent, selective inhibitor of influenza neuraminidase, and its oral prodrug oseltamivir were investigated in three double-blind, placebo-controlled studies. Two studies involved healthy adult volunteers (18-55 years) (n = 48) who received single (20-1000 mg) or bid doses (50-500 mg) (n = 32) of oseltamivir or placebo for 7 days. Healthy elderly volunteers (> or = 65 years) (n = 24) received oseltamivir 100 to 200 mg bid or placebo for 7 days in a third study. Measurable plasma concentrations of the active metabolite appeared rapidly in plasma and were significantly higher and longer lasting than those of oseltamivir. Pharmacokinetics of both compounds were linear. Multiple-dose exposure was predictable from single-dose data, and steady-state plasma concentrations were achieved within 3 days of bid drug administration. Oseltamivir was well tolerated at single doses of up to 1000 mg and twice-daily doses of up to 500 mg. Adverse events were mild in intensity. Exposure to both prodrug and active metabolite was increased in elderly patients by approximately 25%. However, due to the wide safety margin of both compounds, no dose adjustment is necessary for elderly patients.

Acetamides↗

PubMed1999

Effect of dietary fiber on intestinal barrier function of 5-Fu stressed rats.

Chemotherapy might damage intestinal barrier function (IBF). The aim of the study was to evaluate the effect of dietary fiber on IBF of 5-fluorouracil (5-Fu) stressed rats. Thirty Wistar rats after gastrostomy were assigned randomly to one of three groups (10 of each group), Chow, enteral nutrition (EN), or EN+Fiber (2 g/100 ml solution). They kept their diets respectively for 8 days. 5-Fu (75 mg/kg body weight) was injected intraperitoneally on day 4. Urinary recovery ratios of lactulose and mannitol (L%/M%) were measured on day 3 and day 7. The mesenteric lymph nodes were harvested for bacterial translocation (BT). On day 8, small intestine and colon were taken for wet weight, mucosal thickness of both small intestine and colon and villus height of small intestine. The BT rates of Chow and EN+Fiber groups (20% for both) were lower than that of EN group (70%) (P<0.05). The L%/M% of both EN+Fiber (from 0.0265+/-0.0073 to 0.0274+/-0.0068) and Chow groups (from 0.0268+/-0.0039 to 0.0281+/-0. 0044) were unchanged after stress (P>0.05 for both), whereas that of EN group significantly increased (from 0.0289+/-0.0070 to 0.0331+/-0. 0084) (P<0.01). Chow group gained body weight (4.9+/-4.3 g). EN+Fiber group lost less body weight (-3.1+/-3.4 g) than EN group (-6.6+/-5.2 g) (P<0.05). The intestinal structure of Chow and EN+Fiber groups was superior to that of EN group. In conclusion, dietary fiber could protect the IBF of 5-Fu stressed rats.

Animals↗

PubMed1993

[Study on the T cell functions induced by anti-CD3mAb in chronic pulmonary heart disease].

We studied the T lymphocyte transformation and IL-2's functions induced by anti-CD3 mAb in 42 cases of CPHD. The T lymphocyte transformation, activity of IL-2 and expression of IL-2R were determined by 3H-TDR incorporation, bioassay and immunoabsorption methods. The results showed that PBL transformation and activity of IL-2 were decreased in the patients of acute exacerbation stage more than those in controls and remission stage (P < 0.05 or P < 0.01); activity of IL-2 in the patients of remission stage was close to that in controls (P > 0.05), but PBL transformation was still less than that in controls (P < 0.01); Expression of IL-1R were increased in the patients more than in controls (P < 0.01). G.I of anti-CD3mAb and PHA stimulating PBL proliferation showed positive correlation (P < 0.01), activity of IL-2 and expression of IL-2R were not correlated (P > 0.05). The results showed that extrinsic IL-2 could enhance PBL proliferations induced by anti-CD3mAb, especially in CPHD patients.

Aged↗

PubMed1990

[Study on the fibrin fibrinogen degradation products levels and it's significance in the phlegm of the patients with chronic cor pulmonale through monoclonal antibodies].

For the first time, we determined the levels of FDP in phlegm of the patients with chronic cor pulmonale and normal subjects by the TRCHII with the McAbs. Antihuman FDP McAb was applied the clinic, hence, the specificity and sensitivity of TRCHII method for detecting FDP was increased, facilitating clinical application. The results showed that the FDP level of the patients was significantly higher than that of normal subjects (P less than 0.05), but there was no significant difference between the levels of the patients of acute stage and those of remission stage. (P greater than 0.05). The main reason for the increased FDP levels in the phlegm of the patients with chronic cor pulmonale is probably due to the pathological change of the disease-recurrent infections, anoxemia, hypercoagulability and so on. The detection of FDP is helpful for the diagnosis, treatment, evaluation of prognosis of the disease. It provides an index for the observation of tissue damage of lung, especially the damage of capillary endothelia of the lung.

Adult↗

PubMed1989

Low-dose growth hormone and hypocaloric nutrition attenuate the protein-catabolic response after major operation.

To determine the effects of low-dose recombinant human growth hormone (GH) and hypocaloric nutrition on postoperative convalescence, we performed a placebo-controlled randomized double-blind trial in 18 patients after elective gastrectomy or colectomy. The subjects received parenteral nutrition containing 20 calories/kg per day and 1 g protein/kg per day. Daily injections of drug or placebo were given during the first postoperative week. The nine control subjects lost 3.3 kg (5.9% of preoperative weight) and had a cumulative nitrogen loss of 32.6 +/- 4.2 g nitrogen at eight days. The patients receiving GH lost significantly less weight (1.3 kg) and nitrogen loss was 7.1 +/- 3.1 g at eight days (p less than 0.001). Kinetic studies demonstrated that the anabolic effects of GH were associated with increased protein synthesis, and amino acid flux studies across the forearm revealed increased uptake of amino acid nitrogen in the GH-treated patients. Body compositional analysis revealed that the patients receiving GH maintained their lean body mass despite the major surgical procedure. Analysis of hand grip force showed a 10% loss of strength in the control subjects; with GH the patients maintained their grip force throughout the postoperative period. We conclude that the postoperative catabolic response can be modified with GH and hypocaloric nutrition. These metabolic and physiologic effects should now be studied in a larger number of patients to determine if this approach can reduce morbidity, mortality, and length of hospital stay for surgical patients.

Amino Acids↗

PubMed1989

[The effect of enriched branched chain amino acid solution on amino acid metabolism during perioperative total parenteral nutrition support].

A prospective, randomized clinical study was performed in patients underwent subtotal gastrectomy or hemicolectomy. Patients were randomly divided into two groups receiving standard amino acid solution (23% BCAA) or a solution enriched with branched chain amino acid (41% BCAA). Preoperative postprandial plasma amino acid levels were used as base line. The amino acid concentrations in plasma between control group (A) and study group (B) were compared during perioperative period. The dynamics of postoperative plasma amino acid profile of the two groups were similar except that plasma BCAA concentrations were very high in group B. In both groups, the levels of plasma glutamine, alanine, tyrosine, lysine, threonine, arginine, asparagine, and cystine decreased, whereas the levels of plasma methionine, phenylalanine, and tryptophan increased. The solution of 41% BCAA was not found to be superior to standard 23% BCAA in normalizing the disorder of plasma amino acid spectrum during the period of TPN support. The differences of urinary amino acid excretion including 3-MHIS and nitrogen balance between the two groups were not statistically significant. Also the results showed more severe disorder of plasma amino acid profile caused by 41% BCAA solution than by standard solution of 23% BCAA.

Adult↗

PubMed1988

Evaluation of parenteral nutrition in the postoperative patient.

A variety of investigators have attempted to improve nitrogen balance during the postoperative period by modifying the composition of the infused nutrient solutions. This study compared the metabolic effects of administering standard amino acid solutions with a solution enriched with branched chain amino acids (BCAA). A prospective, randomized clinical study was performed in patients who had undergone subtotal gastrectomy or hemicolectomy, and subsequently cared for in the metabolic care unit. The patients were selected from specific entry criteria so that two groups of individuals were comparable. All patients underwent operation without complications. The plasma concentrations of valine and leucine were significantly increased (p less than 0.05 and p less than 0.01, respectively) two days after administration of solutions enriched with BCAA and throughout the entire postoperative period. The plasma glutamine concentrations tended to decrease in both groups; no concentration difference occurred between groups. Nitrogen balance tended to be more positive in the group receiving BCAA but there was no significant difference between groups after operation. Urinary excretion of 3-methylhistidine tended to increase postoperatively in both groups, but no difference occurred between groups. However, the urine excretion of isoleucine increased significantly in the patients receiving infusions enriched with BCAA. Both standard balanced amino acid and amino solutions enriched with BCAA were well tolerated in all patients.

Amino Acids, Branched-Chain↗

PubMed1988