Objective　To investigate the effect of rapid fluid replacement on hemorheology in delayed resuscitation after burn. Methods　A total of 32 dogs inflicted with 40%TBSA full thickness scalding were randomly divided into 4 groups: scald control group(C group), delayed Gelofusion even replacement group (GE group), rapid fluid replacement group (GR group), and delayed plasma rapid fluid replacement group (PR group). The femoral arterial pressure, viscosity of blood and plasma, packed cell volume and aggregation of RBC were detected at the intervals of before and 2, 6, 8, 12, 24, 36 and 48 hours after scalding. Results　The viscosity of blood markedly increased at 2 hours after scalding, and the hemorheology parameters decreased after fluid resuscitation. The hemorheologic parameters were obviously lower in GR group than in GE group at 2 hours after rapid resuscitation, the viscosity of blood and RBC aggregation in GR group were obviously lower than those in PR group. Conclusion　Under the condition of delayed resuscitation after burn, rapid fluid replacement can quickly decreased the state of blood high viscosity and may play a role in improving microcirculation and treating burn shock.

Objective: To investigate the correlation between MRI features and pathology in brain edema at the early stage of severe burn (50％ TBSA Ⅲ degree) in dogs.Methods: Fifty-two dogs were randomized into control, simple burn (SB), burn plus sodium lactate (BSL), and burn plus glucose solution groups (BGS). The manifestation of the brain of control group was compared with that of burn groups at 6, 12, 18 and 24 hours postburn with MRI and pathological examination (gross appearance, electron microscopy and light microscopy).Results: The earliest findings of brain edema were seen at 12 hours after burn in BGS group, in which brain swelling was the main feature of MRI. The decrease of SIR on T1WI was not observed until it was exceeded 10％.Signal of T2WI increased by 8.29％ at 24 hours after burn.It was difficult to distinguish the gray matter from the white matter at the boundary line, which became blurred later. Histological changes of brain edema were observed as early as 6 hours after burn, being accompanied by swelling of endothelial cells and peri-vescular astrocytes, and vacuolation took place in neurons at 12 hours after burn, with different degrees of necrosis of capillary endothelimn,neurons, and axons. These changes became more marked with elapse of time. The BGS group showed the most obvious changes mentioned above at 24 hours after burn.Conclusions: The model of the brain edema after severe burn has the feature of both vasogenic edema and cytotoxic edema on the MRI and pathology. Positive MRI findings lagged behind that of the pathomorphological changes.

OBJECTIVETo explore the diagnostic value of MRI and SPECT in early postburn brain edema in severely burned dogs.

METHODSTwenty-six mongrel dogs were randomized into control (n = 6) and burned groups in which every 5 dogs were allotted to each of following time points: 6, 12, 18 and 24 postburn hours (PBHs). The dogs in burn groups were inflicted with 50% TBSA of III degree skin burn and were infused with 5% glucose solution after 6 PBHs, so that severe early postburn brain edema was produced. MRI and SPECT were employed to observe dynamically the brain of dogs in all groups. The results were collected and compared with one another.

RESULTSThe results indicated that with MRI brain morphological change of early brain edema could be shown as early as within 12 PBH and diffuse brain edema became more obvious with elapse of time. The changes might be difficult to be found by MRI when T(1)WISIR decreased below 10%. T(2)WI SIR increased by 8.29% at 24 PBH with blurred demarcation between the brain gray and white matters. There was diffused and progressive nuclide ((99)TCm-ECD) concentration in the brain tissue as shown by SPECT at 6 PBH. The radio-nuclide taking ratio increased significantly after 12 PBH, especially at 24 PBH (P < 0.01) when compared with that before burn.

CONCLUSIONCombined application of MRI and SPECT could evidently increase sensitivity and specificity in the diagnosis of early postburn brain edema.

Animals ; Brain Edema ; diagnosis ; diagnostic imaging ; Burns ; complications ; Dogs ; Magnetic Resonance Imaging ; Male ; Tomography, Emission-Computed, Single-Photon

OBJECTIVETo investigate the influence of N-acetyl-L-cysteine (NAC) on pulmonary injury and oxygen stress caused by smoke inhalation injury.

METHODSRats inflicted with smoke inhalation injury were employed as the model. WBC in BALF (bronchoalveolar lavage fluid), MPO (myeloperoxidase) activity, hydrogen peroxide (H(2)O(2)) content, GSH (glutathione) content and total antioxidant (TAO) capacity in pulmonary tissue were determined.

RESULTSPostinjury WBC in BALF, MPO activity in pulmonary tissue and H(2)O(2) content decreased obviously after NAC treatment. But the pulmonary tissue contents of GSH and ATO increased evidently after the treatment with NAC.

CONCLUSIONNAC treatment could ameliorate pulmonary oxygen stress after smoke inhalation injury. AS a result, the pulmonary antioxidant capacity was improved.

Acetylcysteine ; pharmacology ; Animals ; Bronchoalveolar Lavage Fluid ; Disease Models, Animal ; Free Radical Scavengers ; pharmacology ; Glutathione ; metabolism ; Hydrogen Peroxide ; metabolism ; Leukocytes ; drug effects ; Oxidative Stress ; drug effects ; Peroxidase ; metabolism ; Rats ; Rats, Wistar ; Smoke Inhalation Injury ; enzymology ; metabolism ; pathology

Objective:To investigate the serum metabolites and their metabolic characteristics of patients with optic neuritis.Methods:Case-control study. From January 2021 to January 2022, 9 serum specimens of diagnosed patients with optic neuritis were collected in Department of Neurology from Beijing Tongren Hospital and 9 healthy subjects as the control. Among them, there were 5 females and 4 males in the optic neuritis group, aged (35.8±12.9) years; there were 5 females and 4 males in the healthy control group, aged (32.6±8.6) years. Liquid chromatography-mass spectrometry was used to detect metabolites in serum of healthy control and patients with optic neuritis. The principal component analysis (PCA) and orthogonal partial least-squares discriminination analysis (OPLS-DA) were used to analyze the differential metabolites . The variable importance projection value of OPLS-DA model and the P value of t-test was applied to find the different metabolites. Results:Thirty-seven metabolites were finally identified from serum samples. Four metabolites with variable important in projection (VIP) values larger than 1 and P values less than 0.05 were teased out, three metabolites, LysoPC (P-16∶0), LysoPC (16∶0), LysoPC (P-18∶0) belonge to phospholipid and one metabolite was L-Threonine, they were all down-regulated. The area under curve were 0.951, 0.889, 0.963 and 0.944, respectively. Conclusion:Based on metabonomic analysis, some metabolites in serum have changed, which can provide basis for biomarkers screening of optic neuritis.