Search PubMed⌕ Search

Biomedical subjects

Z R Guo

Publications and source records attributed to Z R Guo.

At least 37 records · Page 2Linked to original sources
PubMed1995

The association of circulating endotoxaemia with the development of multiple organ failure in burned patients.

In this study, we examined the relationship of plasma endotoxin levels to the development of multiple organ failure (MOF), and the outcome in patients with thermal injury. A prospective cohort study of 17 patients admitted with burns covering more than 70 per cent of body surface area was undertaken. Circulating endotoxin concentrations were measured by modified limulus amoebocyte lysate assay in serial samples of plasma. Seven out of 17 burned patients developed MOF according to multiple criteria. The plasma endotoxin concentrations of patients with MOF were 0.512-1.127 EU/ml, which were significantly higher than that of 10 patients without MOF (0.216-0.553 EU/ml), on 3, 14, 21 and 28 days postburn (p < 0.05-0.01). A significantly higher incidence of positive endotoxin tests (> or = 0.120 EU/ml) was found in patients who developed MOF as compared to those patients who did not develop MOF during the observation period (p < 0.05). As the mean endotoxin levels increased, the incidence of MOF and death rate also increased, and persistent endotoxemia carried a poor prognosis. The present investigation provides further evidence that endotoxemia in severely burned patients commonly occurs. Circulating endotoxin has also been found to be strongly associated with the development of MOF and mortality following major burn injury.

Adult↗
PubMed1994

[Delayed fluid resuscitation induced bacterial translocation after lethal thermal injury: role of oxygen free radical injury of intestinal mucosa].

The Present investigation was undertaken to examine the effect of delayed fluid resuscitation (DFR), after lethal thermal injury on oxygen free radical (OFR) injury of intestinal mucosa and its relationship to bacterial translocation. Four groups of gnotobiotic rats with 5 strains of bacteria were studied: sham injury group (control) (n = 6): early fluid resuscitation (EFR) group (n = 24) receiving resuscitation (Parkland) immediately after scald (40% TBSA, third degree); DFR group (n = 24) receiving resuscitation 6 hours after scald; treatment group (n = 12), rats with DFR receiving VitE and VitC treatment before resuscitation 12, 24, 48 and 72 hours after injury, animals (n = 6, at each point) were sacrificed. Plasma endotoxin level, mucosal SOD, GSHPx, MDA and diamine oxidase (DAO) of ileum were determined, and cultures of the mesenteric lymph nodes (MLN), liver, spleen, heart, lung, kidney and blood were done. The level of mucosal MDA and plasma endotoxin and the incidence of bacteria translocation (IBT) to tissues were significantly higher and mucosal SOD, GSHPx, DAO activity significantly lower in DFR group as compared with that in EFR group at most of the time points. In DFR group, mucosal MDA content was negatively correlated with mucosal DAO activity, which correlated positively with plasma endotoxin level and IBT. After treatment with VitE and VitC, mucosal MDA content was decreased, plasma endotoxin level and IBT were significantly decreased, and mucosal DAO activity was significantly increased. Our data indicated that DFR in cases of burn shock can result in OFR injury of intestinal mucosa, disrupting mucosal barrier and promoting translocation of intestinal bacteria and endotoxin.

Amine Oxidase (Copper-Containing)↗
PubMed1994

[Influential factors of water evaporation from burn wound].

To determine various influential factors of water evaporation from burn wound, we scalded 120 rats and divided them randomly into 12 groups. The rate of evaporation was studied under different temperatures and moistures. The experimental results showed that high temperature and low moisture were beneficial to the treatment of burn wound. Escharectomy, skin grafting and film forming agents could reduce evaporation. Azone could change the permeability of the skin and accelerate water evaporation.

Animals↗
PubMed1993

[Effect of seleno-organic compounds on leukotriene B4 biosynthesis].

Leukotrienes (LTs) are a group of metabolites of arachidonic acid through the 5-lipoxygenase pathway. Among these metabolites, LTB4 is an important mediator of inflammatory disease. Recently, it has been shown that seleno-organic compounds are very biologically active. One of them, Ebselen [2-phenyl-1,2-benzoisoselenazol-3 (2H) one] is a new seleno-organic compound with very low toxicity while exhibits anti-inflammatory activity. Attempt to search for seleno-organic compounds as anti-inflammatory drugs and establish structure-activity relationships, ten ebselen derivatives with modifications in the 2-phenyl moiety were studied with respect to their effects on LTB4 biosynthesis. p-substituted compounds were shown to have stronger inhibitory activity on LTB4 biosynthesis than o-substituted compounds and ebselen itself. Among the p-substituted compounds, polar-inducing group-substituted compounds showed stronger activity than compounds substituted with polar-conjugated groups. Among the compounds substituted with polar-inducing groups, strongpolar groups exhibited stronger activity than weakpolar groups.

Animals↗
PubMed1993

[Escharectomy during shock stage in extremely burned].

In order to stop excessive plasma loss, to alleviate noxious effects of devitalized tissues on the body, and to shorten the hospitalization time, we have attempted to perform extensive escharectomy during the shock period in extensively burned patients. Group 1 consisted of 17 patients, aged 19 to 45 years, with mean total burn area 58 +/- 15.9% TBSA, and full-thickness injury involving 32.0 +/- 17.2% TBSA. The first escharectomy was done at 26.2 +/- 14.6 h postburn, and excision area averaged 32.0 +/- 7.1% (24% to 46%). In 13 of them, Swan-Ganz catheter was introduced to monitor the hemodynamic changes. It was found that RAP, PAP, PAWP, ABP, HR, CO and CI were all stable during and after the operation. Group 2 consisted of 29 patients, in whom escharectomy was begun 4-5 days postburn. The mean healing time of the patients in group 1 was 31.7 days, which was shorter than that of group 2 (40.1 days). The duration of hemoconcentration was shorter in group 1. The amount of blood transfusion was almost 1000 ml less in group 1 during the first two weeks. Less antibiotics were used with fewer visceral complications in group 1. The authors believe that escharectomy during the burn shock stage is feasible.

Adolescent↗
PubMed1993

[Comparison of therapeutic value of various topical agents in Pseudomonas aeruginosa infection. An experimental study].

40 Wistar rats were scalded by boiling water for 12 seconds resulting to 10% TBSA full-thickness burn. Pseudomonas aeruginosa (10(9)/ml) was smeared on the burn wounds 10 min after injury. The animals were divided into 4 groups. Sulfadiazine silver and sulfadiazine zinc (with 5% azone) cream was applied to the wounds of animals in the group 1. The contaminated wounds were irradiated with negative ion current in the group 2. The "moisture ointment" was applied to the wounds in the group 3. Group 4 consisted of the controls without any treatment. All the topical agents were applied to the wounds 4 hr after the injury. The number of bacteria in the subeschar tissue was determined every day for 4 days. The tissues of lung, kidney, liver and heart were examined pathologically on the 4th day. The results showed that the quantity of bacteria in the subeschar tissue was significantly less, and pathological changes in organs were significantly milder in the 1st and 2nd groups than other two groups. The "moisture ointment" group yielded the poorest results in respect to subeschar bacterial counts and visceral pathology.

Administration, Topical↗
PubMed1992

[Evaluation of nutritional in 149 severely burned patients].

By means of random sampling we selected 149 cases with over 30% TBSA burn (> 10% full-thickness) for evaluation of nutriment supplementation during treatment. We analysed daily caloric supply, nitrogen balance, amount of blood transfusion, Hb, A/G, transferrin, leukocyte, lymphocyte, IgG, Fn and body weight. The data support our impression that hyperalimentation can promote wound healing and raise the survival rate.

Adult↗
PubMed1992

[The lead generation of protein tyrosine kinase inhibitors by quantitative structure-activity relationship analysis].

Analysis of the quantitative relationship between a series of substituted benzylidenemalononitriles and the inhibitory action on protein tyrosine kinases were carried out using the Hansch-Fujita method. The results indicate that the presence of two or three hydroxy groups attached to a phenyl ring, which connects an extended (trans form) conjugated chain, is essential to the inhibition. Compared with the structure of other kinds of inhibitors, a presumable basic structure for inhibiting the enzyme was generated.

Benzylidene Compounds↗
PubMed1991

Pulmonary oedema in isolated lung lobe after inhalation injury.

Pulmonary oedema was produced in isolated lung lobes with steam and provided direct continuous measurements of transudation as it occurred. Transvascular flux (Qf) and weight gain (Gw) of the lobe increased immediately and the transudation reached its peak within half an hour after inhalation injury. Studies of protein content, colloid osmotic pressure of bronchial exudate and water content of lung, reconfirmed the increase in pulmonary capillary permeability. Marked haemoconcentration was revealed. Plasma leaked 113 g (25 per cent), plasma protein leaked 1.96 g (9.7 per cent) during the experiment. Based on the measured arterial pressure (Pa), vein pressure (Pv), arterial occlusion (Pao), venous occlusion (Pvo), double occlusion (Pdo) and blood flow through the lobe (Qt), the total vascular (Rt), arterial (Ra), middle compartment (Rmid) and venous (Rv) resistances were calculated. All the resistances were increased and the Qt showed a decrease after inhalation injury.

Animals↗
PubMed1990

[Pulmonary edema in an isolated lobe after inhalation injury].

In order to know the regularity of forming edema after thermal injury, we performed experiments of pulmonary edema in isolated lobes with steam and obtained direct continuous measurements of transudation as it occurs. Transvascular flux (Qf) and gain weight (Gw) of the lobe increased immediately and the peak value of exudation occurred within half an hour after inhalation injury. Studies in protein content, colloid osmotic pressure of bronchus exudate and water content of lung, reconfirmed increase in pulmonary capillary permeability. Marked hemoconcentration was revealed. Plasma leaked 145 ml (32.5%), plasma protein leaked 2.9 g (15%) during the experiment. According to pressure of artery (Pa), vein (Pv), arterial occlusion (Pao), venous occlusion (Pvo), double occlusion (Pdo) and blood flow through the lobe (QT), the total vascular (Rt) arterial (Ra), middle compartment (Rmid), and venous (Rv) resistances were calculated. All the resistances indicated an increase and QT showed a decrease after inhalation injury. The experimental results suggested that tissue ischemia is significant after thermal injury and resuscitation should be started as early as possible and should include whole blood or plasma in resuscitation regimes during burn shock phase.

Animals↗
PubMed1989

[Studies on antipeptic ulcer agents: the synthesis and structure-activity relationship analysis of heterocycle aldehyde (thio) semicarbazones and acyl hydrazones].

Twenty-eight condensation products of heterocycle-alpha-carboaldehydes with N-aminooxazolidones, semicarbazides, thiosemicarbazides, aminoguanidines, aromatic hydrazides and benzoxycarbonyl hydrazide were synthesized so as to deduce the antiulcer pharmacophore or fragment of furazolidone(I), the prototype, which shows therapeutic efficacy for patients with gastric ulcer. Analysis of the SAR of the compounds indicate that the substitution of furan, thiophene, pyrrole and N-methyl pyrrole rings for the 5-nitrofuran and the cleavage of the oxazolidone ring obtain the activity to some extent. The necessary electronic density of carbonyl group of compounds is of importance. A lead structure, therefore, is derived for further optimization.

Animals↗
PubMed1989

[Studies on antipeptic ulcer agents: the synthesis and QSAR analysis of heterocycle aldehyde N4-substituted phenyl(thio)semicarbazones].

Forty-five condensation products of furan-, pyrrole-, and N-methyl pyrrole-alpha-carboaldehyde with N4-3-or 4-substituted phenyl semicarbazides and thiosemicarbazides were designed and synthesized to optimize the antiulcer activity. Quantitative structure-activity relationships reveal that in the series of semicarbazones increase in hydrophobicity of molecules and introduction of electron-repelling groups onto the phenyl ring raise the antiulcer activity; Generally, the activity of semicarbazones is higher than that of the corresponding thiosemicarbazones. The large spans between activity and toxicity of compounds No. 17 and 30 led to further investigation of pharmacological actions.

Animals↗