Analysis of pathological changes of bone hydatid cyst of meriones meridianus after radiotherapy / 中国地方病学杂志

Objective To observe the pathological changes of bone hydatid cyst of meriones meridianus after radiation therapy,and to investigate the clinical effect of radiotherapy on bone hydatid disease.Methods Ascus was dissected sterilely from sheep liver that naturally infected with Echinococcus granulomas,sheared and sac skin removed.Then it was washed and precipitated with 0.9％ sterile saline for 3 times,and scolex was HE stained and counted,from which a 20 ml suspension was made containing 12 × 106/L of scolex.Health meriones meridianus (referred to as gerbil) 140,male and female were in each half,aged 2 to 3 months,body weight(38 ± 6)g,were involved in the study.Gerbil was injected a 0.2 ml suspension containing Echinococcus granulomas scolex into hind tibial periosteum,and X-ray was taken 12 months after the injection.According to the bone destruction in the vaccination site,gerbil hindleg tibia with clear jagged bone destruction was treated as inclusion criteria,and 72 animal were selected as gerbil bone hydatid disease animal models,male and female were in each half.A tatal of 72 gerbils were randomly divided into 4 groups:control group,40 beequerel(Gy) group,50 Gy group and 60 Gy group,18 rats in each group,male and female in each half.The model animals were treated with radiotherapy for 5 times,with 2 d interval,and radiation dose was 300 cGy/min.Each group of gerbils was sacrificed after radiotherapy,bone Echinococcus granulomas cysts was taken out sterilely,and observed by light and electron microscope.Intracapsular cyst fluid was extracted,washed and precipitated with 0.9％ sterile saline repeatedly,and and the pellet was HE stained for observation of scolex morphology and activity by light microscope.Results The morphology and activity ofEchinococcus granulomas in cystic fluid in control group were normal; the morphology and activity of Echinococcus granulomas were still normal in the 40 Gy group,and Echinococcus granulomas was not stained red; but those were abnormal,deformation and atrophy and stained red in the 50 Gy group; and were stained red,deformed,fractured and were wrapped by unknown in the 60 Gy group.By light microscope,the germinal layer,cuticle layer,brood capsule and histological structure of protoscolex were basically normal in irradiated region in the control group.The pathological changes of hydatid cyst in the 40 Gy group were mainly degeneration,structure of hydatid cyst was abnormal,stratum corneum was extensive edema,germinal layer became thinner and the fertile cyst was rare.The main pathological change of hydatid cyst in the 50 Gy group was that corneous layer was widely fractured,and the germinal layer was edema,buckling folds,cells decreased,rare seen brood capsule and scolex; the main pathological changes of hydatid cyst were mainly necrosis in the 60 Gy group,cuticle was extensive fault,stratum corneum and germinal layer was separated,germinal layer was atrophy and disorder,no brood capsule and scolex.By electron microscope,cuticle structure of Echinococcus granulomas cyst was clear,microvillus arranged neatly,morphology and structure of the cell and organelle in cytoplasm were normal in the control group.There were many inflammatory cells infiltrating germinal layer of Echinococcus granulomas cyst,microfilament and contents in microfilament were reduced in the 40 Gy group.Microvillus of Echinococcus granulomas disappeared,nuclear membrane was unclear,endoplasmic and mitochon eclasis,lymphocyte nuclear chromatin was clumping and edge set and in circular permutation in the 50 Gy group.Microvillus disappeared,perinuclear membrane indistinct and ruptured,parts of nucleoli were fragmented and marinated,endoplasmic reticulum was extensive expansion,mitochondria was pyknosis and obvious vacuolization,lymphocyte nuclear chromatin clumping and edge set,lysosomes and macrophage emerge in the 60 Gy group.Conclusions Radiotherapy can destroy the morphology and structure of bone hydatid cyst,radioactivity at 50 Gy has a lethal effect on hydatid cyst.Radiation treatment of bone hydatid disease has a good clinical effect.

Effect of lung stress index on titration of positive end-expiratory pressure at post-recruitment in three canine acute respiratory distress syndrome models / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the relationship of lung stress index and positive end-expiratory pressure (PEEP) at post-recruitment in different canine acute respiratory distress syndrome (ARDS) models.</p><p><b>METHODS</b>The ARDS models were induced by intravenous oleic acid, saline lavage and hydrochloric acid aspiration in anesthetized dogs. During volume control ventilation with constant inspiratory flow, PEEP was set to obtain a b (stress index) value between 0.9 and 1.1 (b = 1) before and post recruitment maneuver (RM). PEEP was changed to obtain b < 1 (0.6 < b < 0.8) and b > 1 (1.1 < b < 1.3). Meanwhile, the recruited volume (RV) was measured and pulmonary mechanics and gas exchange were observed.</p><p><b>RESULTS</b>At b = 1 after RM, PEEP were (10.8 +/- 2.3), (12.8 +/- 1.8) and (9.2 +/- 1.8) cm H2O in the oleic acid, saline-lavaged and hydrochloric acid aspiration groups, respectively. PEEP in saline-lavaged group was higher than that in hydrochloric acid aspiration group (P < 0.05). The ratio of partial arterial oxygen tension and fraction of inspiratory oxygen (PaO(2)/FiO(2)) at b = 1 without RM was lower than those post-RM in all three groups (P < 0.05). In oleic acid group, PaO(2)/FiO(2) at b = 1 post-RM was (399 +/- 61) mm Hg, which was higher than that at b < 1 [(307 +/- 71) mm Hg], but there was no difference between those at b = 1 and b > 1. At b = 1 after RM, PaO(2)/FiO(2) in the saline-lavaged group was higher than that in acid aspiration group, but no difference between saline-lavaged group and oleic acid group was found. At b = 1 post-RM, RV were higher than that at b = 1 before RM in all three groups (P < 0.01), but there was no significant difference among three groups. At b = 1 post-RM in three groups, pulmonary compliance were higher than those at b > 1, but airway plateau pressure were lower than those at b > 1.</p><p><b>CONCLUSIONS</b>Lung stress index could be a good indicator for PEEP titration at post-RM.</p>

Assessment of stroke volume variation and intrathoracic blood volume index on the responsiveness to volume loading in mechanically ventilated canine with hemorrhagic shock / 中华外科杂志

<p><b>OBJECTIVE</b>To assess the significance of stroke volume variation (SVV) and intrathoracic blood volume index (ITBI) on the responsiveness to volume loading in mechanically ventilated canine with hemorrhagic shock.</p><p><b>METHODS</b>Hemorrhagic shock canine model was established with the modified Wiggers' method. The heart rate (HR), mean artery pressure (MAP), central venous pressure (CVP), pulmonary artery wedge pressure (PAWP), intrathoracic blood volume index (ITBI) and stroke volume variation (SVV) were investigated by Swan-Ganz catheter or PiCCO monitor. Graded volume loading (VL) was performed. Successive responsive VLs were performed (increase in SV > 5% after VL) until continuous change in SV < 5% (unresponsive) was reached.</p><p><b>RESULTS</b>Fourteen canines were studied and a total of 134 VLs were performed. In 94 VLs, an increase in SV of more than 5% was reached. In the other 40 VLs, increase in SV was less than 5%. The change of HR, MAP, ITBI, SVV in responsive were more than those of unresponsive after VL. The change of CVP, PAWP in responsive were less than those of unresponsive. Significant correlation was found between DeltaSV after VL and the baseline values of ITBI, SVV. No correlation was found between DeltaSV and HR, MAP, CVP, PAWP. Significant correlations were also found between DeltaSV and DeltaCVP, DeltaPAWP, DeltaITBI, DeltaSVV after fluid loading. No correlation was found between DeltaSV and DeltaHR, DeltaMAP. By using receiver operating characteristic analysis, the area under the curve were 0.872 for SVV and 0.689 for ITBI, more than those of HR, MAP, CVP, PAWP statistically. As SVV value of 9.5% or more will predict an increase in the SV of at least 5% in response to a VL with a sensitivity of 92.6% and a specificity of 82.5%.</p><p><b>CONCLUSIONS</b>SVV and ITBI were more useful indicators than CVP and PAWP on the assessment of responsiveness to volume loading. SVV as a functional preload parameter and for on-line monitoring may help to improve the hemodynamic management.</p>