l-Malic Acid Facilitates Stem Cell-Driven Intestinal Epithelial Renewal through the Amplification of ß-Catenin Signaling by Targeting Frizzled7 in Chicks.

l-Malic acid (l-MA) contributes to energy metabolism and nutrient digestion, which is an alternative to antibiotics for livestock; however, it is not clear whether l-MA can replace antibiotics to promote intestinal development in chicks. To investigate the effects of l-MA on intestinal stem cells (ISCs) driving epithelial renewal, we employed in vivo chick feeding experiments, chick intestinal organoid (IO) models, and in vitro chick intestinal epithelial cell models. The results showed that the feed conversion rate and diarrhea scores were decreased with improved jejunal morphology and barrier function in the 0.5% l-MA group. l-MA promoted the proliferation and differentiation of ISCs, inhibited the cell apoptosis, increased the IO formation efficiency, surface area, budding efficiency, and number of buds, suggesting that l-MA promoted the expansion of ISCs. Furthermore, l-MA treatment dramatically upregulated the Wnt/ß-catenin signaling pathway in the jejunum. Importantly, Wnt transmembrane receptor Frizzled7 (FZD7) mRNA abundance was increased in response to dietary 0.5% l-MA. In addition, molecular docking analysis using Autodock software and isothermal titration calorimetry revealed that l-MA binds to Lys91 of FZD7 with high affinity, indicating a spontaneous interaction. The chick intestinal epithelial cells treated with 10 µM l-MA significantly increased cell viability, and the Wnt/ß-catenin signaling pathway was activated, but l-MA failed to upregulate the Wnt/ß-catenin signaling when treated with the FZD7-specific inhibitor Fz7-21 in chick intestinal epithelial cells, indicating that FZD7 is indispensable for l-MA activation of the Wnt/ß-catenin signaling. Collectively, l-MA stimulated ß-catenin signaling by targeting transmembrane receptor FZD7, which promoted ISC expansion and inhibited cell apoptosis to accelerate intestinal epithelial renewal in chicks.

Novel recombinant R-spondin1 promotes hair regeneration by targeting the Wnt/ß-catenin signaling pathway.

Roof plate-specific spondin 1 (R-spondin1, RSPO1) is a Wnt/ß-catenin signaling pathway activator that binds with Wnt ligands to stimulate the Wnt/ß-catenin signaling pathway, which is key to hair regeneration. However, it is not clear whether recombinant RSPO1 (rRSPO1) affects hair regeneration. Here, we treat C57BL/6 male mice with rRSPO1 and investigate the expression of the Wnt/ß-catenin signaling pathway and the activation of hair follicle stem cells in the dorsal skin. The mouse skin color score and hair-covered area are determined to describe hair growth, and the skin samples are subjected to H&E staining, western blot analysis and immunofluorescence staining to evaluate hair follicle development and the expressions of Wnt/ß-catenin signaling pathway-related proteins. We find that rRSPO1 activates mouse hair follicle stem cells (mHFSCs) and accelerates hair regeneration. rRSPO1 increases the hair-covered area, the number of hair follicles, and the hair follicle diameter and length. Moreover, rRSPO1 enhances the activity of Wnt/ß-catenin signaling pathway-related proteins and the expressions of HFSC markers, as well as mHFSC viability. These results indicate that subcutaneous injection of rRSPO1 can improve hair follicle development by activating the Wnt/ß-catenin signaling pathway, thereby promoting hair regeneration. This study demonstrates that rRSPO1 has the potential to treat hair loss by activating the Wnt/ß-catenin signaling pathway.

Dietary supplementation with probiotics increases growth performance, improves the intestinal mucosal barrier and activates the Wnt/ß-catenin pathway activity in chicks.

BACKGROUND: Probiotics comprise effective feed additives that can replace antibiotics in animal livestock production. However, mono-strain probiotics appear less effective because of their instability. Therefore, the present study aimed to investigate dietary supplementation with compound probiotics (CPP) on growth performance, diarrhea rate and intestinal mucosal barrier, as well as the possible molecular mechanism, in chicks. In total, 360 1-day-old chicks of the Hy-Line Brown Chicks were randomly divided into the control group (CON, basal diet), chlortetracycline group (500 mg kg-1 CTC) and compound probiotics group (1000 mg kg-1 CPP, consisting of Bacillus subtilis, Bacillus licheniformis, Enterococcus faecium and yeast). The experiment period was 56 days. RESULTS: The results showed that, in comparison with the CON group, CPP significantly increased the average daily feed intake and average daily gain of chicks and reduced diarrhea (P < 0.05). The probiotic group exhibited increased immune organ (i.e. spleen and thymus) mass and increased levels of serum immunoglobulin (Ig)A, IgM and IgG (P < 0.05) compared to the CTC group. In addition, the jejunal mass and morphology were improved in the probiotic group (P < 0.05). Moreover, CPP reinforced jejunal barrier function, as indicated by increased transepithelial electrical resistance, protein expression of occludin and claudin-1, and diamine oxidase levels in the jejunum (P < 0.05). Likewise, enhanced fluorescence signals of proliferating cell nuclear antigen-labeled mitotic cells and villin-labeled absorptive cells in the jejunum (P < 0.05) suggested that CPP promoted intestinal stem cells activity. Mechanistically, the Wnt/ß-catenin signaling pathway, including ß-catenin, TCF4, c-Myc, cyclin D1 and Lgr5, was amplified in the jejunum by CPP addition (P < 0.05). CONCLUSION: The present study demonstrated that dietary supplementation with CPP reinforced the jejunal epithelial integrity by activating Wnt/ß-catenin signaling and enhanced immune function in chicks. © 2023 Society of Chemical Industry.

Dietary replacement of soybean meal by fermented feedstuffs for aged laying hens: effects on laying performance, egg quality, nutrient digestibility, intestinal health, follicle development, and biological parameters in a long-term feeding period.

This study aimed to investigate the effects of dietary supplementation with fermented soybean meal (FSM) or fermented miscellaneous meal (FMM, cottonseed meal: coconut meal = at a 1:1 ratio) on the intestinal health, laying performance, egg quality, and follicle development of laying hens. A total of 1,008 54-wk-old laying hens were randomly divided into 7 treatment groups and fed a corn-soybean base diet in addition to 2%, 4%, and 8% FSM or FMM. The results showed that fermentation increased the contents of crude protein, amino acids (Ser, Gly, Cys, Leu, Lys, His, and Arg), and organic acids (butyric acid, citric acid, succinic acid) and decreased the contents of neutral and acid detergent fiber in the soybean and miscellaneous meals (P < 0.05). Compared with the results found for the control group, feeding with 4% FSM increased the egg production, egg mass and average daily feed intake (ADFI), and feeding with 4% FMM increased the ADFI of laying hens (P < 0.05). Furthermore, feeding with 8% FMM reduced the productive performance and laying performance, supplementation with 4% FSM increased the eggshell strength and weight, and 2 to 4% FSM increased the egg albumen height and Haugh unit (P < 0.05). Moreover, 2 to 8% FSM or 2 to 4% FMM enhanced the apparent digestibility of dry matter, crude protein, and NDF for laying hens (P < 0.05). The relative weight, villus height, crypt depth, and villus:crypt ratio of the jejunum were higher in the 4% FSM- and FMM-fed groups (P < 0.05). Moreover, diamine oxidase (DAO) activity, transepithelial electrical resistance (TEER), and the expression of tight junction proteins (ZO-1, Occluding, and Claudin1), the intestinal stem cell marker Lgr5, and the proliferation cell marker proliferating cell nuclear antigen (PCNA) was upregulated in the jejunum of laying hens fed 4% FSM and FMM (P < 0.05). The relative weight of the ovaries, and the number of small yellow follicles and large white follicles were elevated after 4% FSM or FMM supplementation. Furthermore, the levels of serum follicle-stimulating hormone and luteinizing hormone were increased in the 4% FSM and FMM groups (P < 0.05). In conclusion, the supplementation of laying hen feed with FSM and FMM improved the laying performance, egg quality, intestinal barrier function, and follicle development of aged laying hens, and 4% FSM supplementation was optimal.

A quickly, effectively screening process of novel corona virus disease 2019 (COVID-19) in children in Shanghai, China.

BACKGROUND: A recent cluster of pneumonia cases in China was caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We report the screening and diagnosis of corona virus disease 2019 (COVID-19) in our hospital. METHODS: Developed a procedure for the identification of children cases with COVID-19 in outpatient and emergency department of our hospital, then we observed how this process works. RESULTS: (I) There were 56 cases considered suspected cases, and 10 cases were confirmed as COVID-19. (II) Of the 10 confirmed COVID-19 cases admitted in our hospital, 5 were males and 5 were females, aged from 7 months to 11 years, the average age is 6.0±4.2 years, 6 cases were mild pneumonia, the others were upper respiratory tract infection. (III) We followed up 68 patients in isolation at home until symptoms disappeared. Non were missed in the patient's first visit. The sensitivity of this method is 100% and the specificity is 71.3%. CONCLUSIONS: Our screening process works well, and it is also necessary to establish a screening network in the hospital.

Alterations of complex IV in the tissues of a septic mouse model.

OBJECTIVES: To characterize the mitochondrial respiratory chain complex IV(complex IV) activity and protein expression during polymicrobial sepsis. MATERIAL AND METHODS: Polymicrobial peritonitis, a clinically relevant mouse model of sepsis, was generated by cecum ligation and puncture (CLP) in Sprague- Dawley rats. The rats were randomly divided into 3 groups as follows: the sepsis without resuscitation (S), sepsis and fluid resuscitated (R) group, and a control (C) group. Twelve hours after the sepsis model was established, tissue specimens were obtained from the myocardium, liver and skeletal muscle. Mitochondrial respiratory chain complex IV activity of all tissue specimens was detected by spectrophotometry. Western blot was used to measure the liver mitochondrial respiratory chain complex IV protein content. The ultrastructure changes of mitochondria were detected by transmission electron microscopy. RESULTS: In myocardial cells, complex IV activity decreased significantly in the S and R groups as compared to the C group. There were no differences in complex IV activity between groups in skeletal muscle cells while in liver cells, complex IV activity and content was significantly decreased for the S group but no differences were observed between the C and R groups. Increased matrix volume and reduced density with generalized disruption of the normal cristae pattern was most extensive in the liver, followed by cardiac muscle cells with that in skeletal muscle cells been relatively mild in the S group. Mitochondrial fusion/fission and mitochondrial autophagy was also observed in the S group by transmission electron microscopy. Mitochondrial ultrastructure was preserved in the R-group and was similar to that seen in the C-group. CONCLUSIONS: Changes in complex IV activity and mitochondrial ultrastructure, a manifestation of the mitochondrial dysfunction varied depending on cell type. These changes are partly reversed by fluid therapy. Therapies aimed at mitochondrial resuscitation should be explored.

[Application of extracorporeal membrane oxygenation in children with acute respiratory distress syndrome].

The children with acute respiratory distress syndrome (ARDS) usually require ventilatory support treatment. At present, lung protective ventilation strategy is recommended for the treatment of ARDS. Extracorporeal membrane oxygenation (ECMO) can improve oxygenation and remove carbon dioxide by extracorporeal circuit, and can partially or completely take over cardiopulmonary function. ECMO support showed many advantages in treating severe ARDS, such as reducing ventilator-induced lung injury and correcting hypoxemia. Over the past few years, there has been an increase in the use of ECMO for ARDS in children. This paper reviews the applications of ECMO for the treatment of ARDS in children.

Suppression of plasminogen activator inhibitor-1 by inhaled nitric oxide attenuates the adverse effects of hyperoxia in a rat model of acute lung injury.

INTRODUCTION: Locally increased expression of plasminogen activator inhibitor-1 (PAI-1) in acute lung injury (ALI) is largely responsible for fibrin deposition in the alveolae and lung microvasculature. In vitro, nitric oxide (NO) effectively suppresses the ischemic induction of PAI-1. We aimed to investigate the effects of inhaled NO on PAI-1 expression in ALI in a rat model with and without hyperoxia. MATERIALS AND METHODS: Healthy adult rats were primed with lipopolysaccharide (LPS) via an intraperitoneal challenge followed by a second dose of LPS given intratracheally to induce ALI (LPS group), whereas the control groups were given sterile saline. All groups were allocated to subgroups according to gas exposure: NO (20 parts per million, NO), 95% oxygen (O), both (ONO), or room air (A). At 4h, 24h, 48h (after 4h or 24h exposure to the various gases, 24h gas intervention and then observation until 48h), the rat lungs were processed and PAI-1 protein and mRNA expression, histopathological lung injury scores and fibrin deposition were evaluated. RESULTS: At 4 and 24h, inhaled NO caused the PAI-1 mRNA levels in the LPS-NO and LPS-ONO subgroups to decrease compared with the untreated LPS subgroups. At 48h, higher PAI-1 mRNA levels than those of the corresponding control subgroup were only observed in the LPS-O subgroup, and these values were lower in the LPS-ONO subgroup than in the LPS-O subgroup. The trends of the PAI-1 protein levels mirrored those of PAI-1 mRNA. At 48h, PAI-1 protein levels in the LPS-NO and LPS-ONO subgroups were decreased compared with those in the untreated LPS subgroups. The histopathological lung injury scores and fibrin deposition in LPS subgroups that inhaled NO showed a decreasing trend compared with the untreated LPS subgroups. CONCLUSIONS: Inhaled NO can suppress elevated PAI-1 expression in rats with ALI induced by endotoxin. Although exposure to high-concentration oxygen prolongs the duration of PAI-1 mRNA overexpression in ALI, inhaled NO can reduce this effect and alleviate both fibrin deposition and lung injury.

The passive leg raise test to predict fluid responsiveness in children--preliminary observations.

OBJECTIVE: To assess whether the passive leg raising (PLR) test can predict fluid responsiveness in pediatric patients. METHODS: This was a prospective observational study in a tertiary care pediatric center. Hemodynamic parameters including heart rate, stroke volume and cardiac output were assessed at baseline, after passive leg raising (PLR), at second baseline, and after volume loading (10 mL/kg normal saline in 10 min). Cutoff values of 7.5 and 10 % increase in cardiac index (CI) with passive leg raising were explored as predictors of volume loading response. RESULTS: Overall, the changes in CI with passive leg raising varied widely and was a poor predictor of response to volume loading in children under 5 years of age. Of 40 patients, 23 had greater than 10 % increase in CI with PLR which predicted fluid responsiveness with a sensitivity of 94 % (95 % confidence interval 71,100) and specificity of 26 % (95 % confidence interval 10,48). Sensitivity was higher (100 % vs. 91 %) and specificity similar (27 % vs. 25 %) in predicting CI for those over 5 as compared to under 5 y, respectively. In patients over 5 y, simple linear regression revealed a positive correlation (R(2) = 21) while R(2) values were much lower (0-0.07) for those under 5 y. CONCLUSIONS: Cardiac index changes after PLR varies widely in children and may be a poor predictor to volume loading in children under 5-y-old. However, in those over 5 y, PLR may be helpful in predicting fluid responsiveness in pediatric patients.

Predictive value of pediatrics end-stage liver disease or model for end-stage liver disease score in the prognosis of pediatric acute liver failure treated with artificial liver support system / 中华儿科杂志

<p><b>OBJECTIVE</b>To investigate the predictive value of pediatrics end-stage liver disease (PELD) or the model for end-stage liver disease (MELD) in the prognosis of pediatric acute liver failure (PALF) treated with artificial liver support system (ALSS).</p><p><b>METHOD</b>The clinical data of 47 children with acute liver failure seen from August 2008 to July 2013 treated in Children's Hospital, Fudan University were analyzed. Thirty children were treated with ALSS in addition to conventional comprehensive medical treatment (ALSS group). Seventeen children were treated with only conventional comprehensive medical treatment (control group). The main biochemical parameters and coagulation function parameters before and after treatment were compared in the ALSS group and the mortality rates were compared between the two groups. The patients were graded by PELD or MELD when they were hospitalized and the relationship of PELD or MELD scores and mortalities of child patients with the receiver operating characteristic curve (ROC) were analyzed.</p><p><b>RESULT</b>There were significant differences in total bilirubin (TB) ((302 ± 208) vs. (161 ± 129) µmol/L); alanine aminotransferase (ALT) ((161 ± 225) vs. (761 ± 834) U/L); aspartate aminotransferase ( AST) (66 (35, 123 ) vs. 447 (184, 1,129 ) U/L) ; international normalized ratio (INR) ((2.6 ± 1.6) vs. (5.1 ± 4.0)); prothrombin time activity percentage (PTA) ((42 ± 25)% vs. (22 ± 13)%); albumin( ALB) ((35 ± 5) vs. (33 ± 6) g/L) in the ALSS group after treatment. Through the ROC curve analysis, the best PELD/MELD threshold was 25 to predict the patients survival after ALSS therapy, with a sensitivity of 92. 3% , and a specificity of 94.1% at the cutoff point. The area under the ROC curve was 0. 912. The mortality of patients with PELD or MELD score below 25 in the ALSS group (1/13) was lower than the control group (3/4) (P = 0.022), and the mortality of patients with PELD or MELD score over 25 (16/17) was higher than that of the control group (10/13) (P = 0.290).</p><p><b>CONCLUSION</b>PELD or MELD score is a valid index in prognostic evaluation of ALSS therapy, which may provide an evidence for the therapeutic strategies of PALF. Patients with PELD or MELD score below 25 treated with ALSS obtained more benefit.</p>

[Protective effect of an angiotensin-converting-enzyme inhibitor on neurogenic pulmonary edema in rabbits].

OBJECTIVE: Neurogenic pulmonary edema (NPE ) was indicative of poor prognosis in the epidemic of enterovirus 71 infections. The pathogenesis of NPE remains poorly understood. The objectives of this experimental study were to explore whether RAS is activated during NPE in rabbit models induced by fibrin and the effects of an angiotensin converting enzyme inhibitor (enalaprilat) on NPE. METHOD: NPE models were induced by intracisternal injection of fibrinogen and thrombin. According to random number table method, 18 healthy adult New Zealand rabbits were assigned to three groups (with 6 in each) : normal control group (Con group), NPE group and enalaprilat treated (Ena) group. After establishment of NPE models, rabbits in Ena group were given intravenous enalaprilat 0.5 mg/kg. Expression of ACE,ACE2,AT1R mRNA of the lung tissue were evaluated by real-time polymerise chain reaction; and Ang II of the lung tissue was determined by enzyme linked immunosorbent assay ( ELISA ). Meanwhile, histopathological lung injury scores were evaluated. RESULT: ACE mRNA expression level in NPE group ( 17.2 ± 3.3) appeared an increasing trend in contrast to Con group ( 12.6 ± 5.2 ) and Ena group ( 11.5 ± 2.4, both P > 0.05 ). Compared with Con group (81 ± 22 ), ACE2 mRNA expression levels of NPE group ( 52 ± 6 ) and Ena group ( 45 ± 13 ) both decreased ( both P < 0.05 ) . ACE mRNA/ACE2 mRNA expression levels of NPE group ( 0.33 ± 0.06 ) and Ena group ( 0.26 ± 0.04 ) were higher than those of Con group ( 0.16 ± 0.05, both P < 0.05 ), as well as the ratio of Ena group decreased compared with untreated NPE group ( 0.26 ± 0.04 vs. 0.33 ± 0.06, P < 0.05 ) . There were no statistically significant differences in expression of AT1 mRNA of the lung tissue among three groups, but Ena group ( 4.8 ± 1.1) in contrast to NPE group ( 6.7 ± 1.3) has no significant difference (P > 0.05). Lung AngII level of NPE group [(540 ± 147) pg/ml] was significantly higher than that of Con group [(253 ± 37 ) pg/ml] and Ena group [(309 ± 35 ) pg/ml, both P < 0.05 ]. Gross pathologic examination showed that pink foamy edema fluid appeared in the tracheal tubes in NPE group, but spontaneously appeared in neither Con group nor Ena group; and the level of pulmonary subpleural bleeding in Con group, 12 graded 0; in NPE group, 2 graded II, 10 graded III; in Ena group, 2 graded, 8 grade II, 2 grade III. The histopathologic lung injury scores in Ena group was decreased in contrast to NPE group (1.36 ± 0.26 vs.2.32 ± 0.49, P < 0.05) and mainly for the improvement of alveolar overdistension and interstitial edema. CONCLUSION: The present study showed that when NPE occurs, a high lung AngII concentration was associated with an imbalance between ACE mRNA to ACE2 mRNA expression level. Activated local RAS in lung tissue resulted in lung injury. Enalaprilat treatment may attenuate lung injury by interventing local RAS in lung tissue with decreased ratio of ACE mRNA to ACE2 mRNA and lung AngII concentration. The result will be significant for the angiotensin converting enzyme inhibitor used in the theatment of NPE.

[Effect of thrombelastography in the diagnosis of disseminated intravascular coagulation in children].

OBJECTIVE: To study the effect of thrombelastography (TEM) in the diagnosis of disseminated intravascular coagulation (DIC) in children. METHOD: The data of 117 children suffering from DIC in the pediatric intensive care unit (PICU) and Cardiologic ICU (CICU) in the authors' hospital from January 2010 to June 2012 were collected. Ninety-four children without DIC were enrolled into the control group. The platelet count, prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen (FIB), D-dimers and TEM were determined. The sensitivity and specificity of TEM were measured and the relevance of TEM and DIC was investigated to evaluate the effect of TEM and the conventional tests of the coagulation system in the diagnosis of DIC in children. RESULT: The average R reaction time in the DIC group was significantly longer than that in the control group[(13.3 ± 3.3)s vs. (4.5 ± 2.6)s, P = 0.000 5], and the average α-angle in the DIC group was smaller than that in the control group significantly (37.2° ± 1.4° vs. 55.6° ± 3.8°, P = 0.001 0). There was significant decrease in the maximal amplitude (MA) and amplitude (A) in the DIC group, compared with the control group. The OR value (95%CI) of the R reaction time,α-angle and MA was 3.538 (1.298-5.389), 2.472 (1.820-2.224) and 0.256 (0.263-0.831) respectively, which suggests good correlation with the existence of DIC (all P < 0.01). The specificity of R reaction time, α-angle and MA was higher than that of PT, APTT and D-dimers (85.7%, 73.5% and 72.9% vs. 27.0%, 42.1% and 68.2%) . The average R reaction time of children suffering from hemorrhage of severe liver disease(n = 36) was significantly longer than that of 40 healthy children [(9.2 ± 2.7) vs. (2.3 ± 1.8)s, P = 0.001 0], while the α-angle (42.8° ± 7.6° vs. 59.2° ± 10.8°, P = 0.040 0) and the MA value [(33.9 ± 5.1) vs.(56.0 ± 8.1) mm, P = 0.020 0] were significantly smaller. The average R reaction time of children suffering from congenital coagulopathy was significantly longer than that of healthy children [(6.8 ± 3.1) vs. (2.3 ± 1.8)s, P = 0.003 0], too. CONCLUSION: TEM, which has high specificity, is beneficial to the diagnosis of DIC in children.

[Changes of the hemodynamics and extravascular lung water after different-volume fluid resuscitation in a piglet model of endotoxic shock].

OBJECTIVE: Practice recommendations have evolved, and consensus now exists among leading organizations such as the American College of Critical Care Medicine (ACCM) and Surviving Sepsis Campaign that fluid infusion is best initiated with boluses of 20 ml/kg, commonly requires 40-60 ml/kg but can be as much as 200 ml/kg if the liver is not enlarged and/or rales are not heard. The present study aimed to investigate and compare the changes of the hemodynamics and extravascular lung water after higher volume fluid resuscitation in a piglet model of endotoxic shock. METHOD: Twenty piglets were used for establishing animal models of endotoxic shock by intravenous infusing lipopolysaccharide (LPS). The experimental animals were divided into three groups according to the volume infused during the resuscitation. The three groups received different volume of saline in less than an hour after endotoxic shock. By the PiCCO plus system, we investigated the changes of hemodynamics and extravascular lung water. RESULT: After fluid resuscitation, global end diastolic volume inder, (GEDI) and intrathoracic blood volume index, (ITBI) markedly increased in the group of 80 ml/kg and 120 ml/kg, but there was no change in the group of 40 ml/kg. GEDI: Fifteen min after fluid resuscitation R1 was (261 ± 64) ml/m(2), R2 (457 ± 124) ml/m(2), R3 (413 ± 148) ml/m(2), 4 h R1 (251 ± 68) ml/m(2), R2 (422 ± 70) ml/m(2), R3 (470 ± 160) ml/m(2); ITBI: Fifteen min after fluid resuscitation R1 was (335 ± 69) ml/m(2), R2 (550 ± 179) ml/m(2), R3 (520 ± 183) ml/m(2), 4 h R1 (314 ± 84) ml/m(2), R2 (534 ± 96) ml/m(2), R3 (594 ± 200) ml/m(2) (R1 vs. R2 vs. R3, F = 26.373, P < 0.05; R1 vs. R2, R1 vs. R3, P < 0.05; R2 vs. R3, P > 0.05). CI of all three groups significantly decreased when the models were established. After fluid resuscitation, the base level was maintained in the group of 80 ml/kg and 120 ml/kg, but it was under the basic level in the group of 40 ml/kg.Fifteen min after fluid resuscitation R1 was (4.5 ± 0.7) L/(min·m(2)), R2 (6.4 ± 2.2) L/(min·m(2)), R3 (5.5 ± 0.7) L/(min·m(2)), 4 h R1 (4.1 ± 1.0) L/(min·m(2)), R2 (5.2 ± 0.9) L/(min·m(2)), R3 (5.1 ± 0.8) L/(min·m(2)). There was no significant difference in CI between these two groups (P > 0.05).ELWI of the group of 80 ml/kg and 120 ml/kg were still higher than that of the group of 40 ml/kg, 15 min after fluid resuscitation R1 was (19.2 ± 8.6) ml/kg, R2 (29.2 ± 5.5) ml/kg, R3 (23.4 ± 8.2) ml/kg, 4 h R1 (18.3 ± 6.5) ml/kg, R2 (23.8 ± 2.6) ml/kg, R3 (21.4 ± 3.9) ml/kg, but there was no significant difference in ELWI among the groups (P > 0.05). CONCLUSION: Resuscitation with higher volume of fluid infusion in the early stage of endotoxic shock was more efficient to increase the preload and maintain the cardiac output at the baseline level, and might reduce the need for vasoactive agents. Meanwhile, resuscitation with higher volume of fluid in the early stage of endotoxic shock did not sharply increase the extravascular lung water.

[Effects of high volume hemofiltration on hemodynamics and oxygen metabolism at early stage of septic shock in piglet models].

OBJECTIVE: To observe the effects of hemofiltration at early stage of septic shock with different ultrafiltration doses, including hemodynamics, oxygen metabolism, inflammatory mediator in piglet models, and to evaluate the therapeutic effects of HVHF. METHOD: The 18 healthy young piglets (Shanghai species) were divided randomly into three groups:control group (n = 6), conventional volume hemofiltration (CVVH) group [n = 6, ultrafiltration volume = 30 ml/(kg·h)] and high volume hemofiltration (HVHF) group [n = 6, ultrafiltration volume = 50 ml/(kg·h)], the animal model of septic shock was established by injection of lipopolysaccharide (LPS) (150 µg/kg) O111: B4. During the experiment, the following observations were carried out for all groups:1) Changes of hemodynamics [heart rate (HR), mean arterial pressure (MABP), cardiac output (CO), systemic vascular resistance index (SVRI), intrathoracic blood volume (ITBV)] and oxygen metabolism [oxygen delivery (DO2), oxygen consumption (VO2), oxygen extraction rate (O2ER) ] at the time of B0h, 0 h, 2 h, 4 h and 6 h.2) changes of TNF-α, IL-6, IL-10 in plasma at different time points (B0h, 0 h, 2 h, 4 h, 6 h). RESULT: Significant difference in circulatory parameters, inflammatory mediators in plasma were found at B0h and 0 h among three groups; the CO in two treatment groups were higher than that in control group at 4 h, 6 h after model establishment (P < 0.05), and SVRI in HVHF groups were higher than that in other two groups at 4 h, 6 h after model was established (P < 0.05). The MABP in HVHF group [4 h (82 ± 17) mm Hg, 6 h (80 ± 12) mm Hg](1 mm Hg = 0.133 kPa) were higher than that in CVVH group at 4 h [(67 ± 12) mm Hg], 6 h [(69 ± 14) mm Hg] after model was established (P < 0.05). The levels of IL-6, IL-10, TNF-α in two treatment groups were lower than that in control group at 4 h and 6 h after model was established (P < 0.05), and the IL-6 [(281 ± 51) pg/ml], TNF-α [(67 ± 13) pg/ml] level in HVHF group was lower than that in CVVH group [IL-6(281 ± 51) pg/ml, TNF-α (67 ± 13) pg/ml] at 6 h (P < 0.05). The DO2 and VO2 in two treatment groups were higher than that in control group at 4 h, 6 h (P < 0.05), the O2ER in HVHF group were higher than that in CVVH group at 4 h (44% ± 3% vs. 33% ± 4%), 6 h (43% ± 5% vs. 31% ± 3%, P < 0.05). CONCLUSION: High volume hemofiltration (HVHF) at early stage of septic shock piglet models was more effective in improving hemodynamics, oxygen metabolism than conventional CVVH. And HVHF eliminated blood inflammatory mediators more effectively than conventional CVVH.

Effect of continuous blood purification on concentrations of plasma vasoactive substances and cardiac function in endotoxic shock.

OBJECTIVE: To evaluate the effect of continuous blood purification on cardiac function and plasma vasoactive substances in endotoxic shock in piglets. DESIGN: This was a randomized controlled trial in an animal laboratory in a tertiary care pediatric center. MATERIALS AND METHODS: Twenty-three healthy Shanghai white piglets weighing 8-14 kg were randomly assigned to one of the four groups: control group (n = 5), continuous blood purification without lipopolysaccharide infusion group (continuous blood purification, n = 6), lipopolysaccharide-induced endotoxin shock without continuous blood purification group (lipopolysaccharide, n = 6), and lipopolysaccharide-induced endotoxin shock with continuous blood purification group (continuous blood purification/lipopolysaccharide, n = 6). INTERVENTIONS: The lipopolysaccharide and continuous blood purification/lipopolysaccharide groups were injected intravenously with Escherichia coli endotoxin to induce septic shock. The continuous blood purification and continuous blood purification/lipopolysaccharide groups received continuous venovenous hemodiafiltration right after model establishment. At baseline state (T0), following the injection of lipopolysaccharide (T), 1 hr later (T1), 3 hrs later (T3), and 5 hrs later (T5) after model establishment, clinical systemic inflammatory response syndrome parameters, hemodynamic indexes, and plasma concentration of vasoactive substances were obtained. Plasma concentration of dopamine was measured by enzyme-linked immunosorbent assay (DSL Company) and endothelin-1 by enzyme-linked immunosorbent assay (R&D Company). Nitric oxide synthase activity was measured by chromatometry (Nanjing Jiancheng Bioengineering Institute, China). MEASUREMENTS AND MAIN RESULTS: In continuous blood purification/lipopolysaccharide group, after treatment with CPB, heart rate decreased significantly (p < .05) and pulse contour cardiac index, systematic vascular resistance index, and stroke volume index increased significantly (p < .05) when compared with lipopolysaccharide and continuous blood purification groups. After treatment with continuous blood purification, dopamine and endothelin-1 level increased and nitric oxide synthase activities decreased in continuous blood purification/lipopolysaccharide group when compared with the lipopolysaccharide group. In the continuous blood purification/lipopolysaccharide group, improvement in hemodynamic indexes was strongly correlated with increases in plasma dopamine and endothelin-1 level and decreases in nitric oxide synthase activity (r > .9, p < .05). CONCLUSIONS: The adverse cardiovascular effects of lipopolysaccharide-induced endotoxin shock can be improved by continuous blood purification. Improvement is correlated with increases in the concentration of plasma vasoactive substances (endothelin and dopamine) and decreases in nitric oxide synthase activity.

Mortality and morbidity of acute hypoxemic respiratory failure and acute respiratory distress syndrome in infants and young children.

BACKGROUND: Acute hypoxemic respiratory failure (AHRF) often develops acute respiratory distress syndrome (ARDS), and its incidence and mortalities in critically ill pediatric patients in China were 2% and 40% respectively. This study aimed at prospectively investigating incidence, causes, mortality and its risk factors, and any relationship to initial tidal volume (V(T)) levels of mechanical ventilation, in children £5 years of age with AHRF and ARDS. METHODS: In 12 consecutive months in 23 pediatric intensive care units (PICU), AHRF and ARDS were identified in those requiring > 12 hour intratracheal mechanical ventilation and followed up for 90 days or until death or discharge. ARDS was diagnosed according to the American-European Consensus definitions. The mortality and ventilation free days (VFD) were measured as the primary outcome, and major complications, initial disease severity, and burden were measured as the secondary outcome. RESULTS: In 13 491 PICU admissions, there were 439 AHRF, of which 345 (78.6%) developed ARDS, resulting in incidences of 3.3% and 2.6%, and corresponding mortalities of 30.3% and 32.8% respectively along with 8.2 and 6.7 times of relative risk of death in those with pneumonia (62.9%) and sepsis (33.7%) as major underlying diseases respectively. No association was found in V(T) levels during the first 7 days with mortality, nor for V(T) at levels < 6, 6 - 8, 8 - 10, and > 10 ml/kg in the first 3 days with mortality or length of VFD. By binary Logistic regression analyses, higher pediatric risk of mortality score III, higher initial oxygenation index, and age < 1 year were associated with higher mortality or shorter VFD in AHRF. CONCLUSIONS: The incidence and mortalities of AHRF and ARDS in children £5 years were similar to or lower than the previously reported rates (in age up to 15 years), associated with initial disease severity and other confounders, but causal relationship for the initial V(T) levels as the independent factor to the major outcome was not found.

[Recruitment maneuver in the treatment of young piglets with acute lung injury].

OBJECTIVE: To study the feasibility, efficiency and any benefits of recruitment maneuver (RM) in the facilitation of lung repair during recovery from ALI in acute lung injury (ALI) model of young piglets. METHODS: The piglet model of ALI was established by an intravenous injection of lipopolysaccharide (LPS). Twelve ALI piglets were randomly divided into two groups: conventional ventilation (CON) and RM with low tidal volume. Arterial blood gas, dynamic lung compliance (Cdyn) and systematic hemodynamics were monitored during the treatment. TGF-ß1 levels in bronchoalveolar lavage fluid (BALF) and plasma were measured. The mRNA expression of TGF-ß1 in the lungs was assessed by real time PCR. Lung tissue was examined for morphological changes. RESULTS: No significant difference was observed in cardiac output and peripheral vascular resistance (PVR) between the two groups. The extravascular lung water index (ELWI) from 6 hrs after ALI inducement and the pulmonary vascular permeability index (PVPI) 8 hrs after ALI inducement in the RM group decreased significantly compared with the CON group. Cdyn in the RM group increased quickly 1 hr after ALI inducement, and there was a significant difference between the two groups (P<0.05). P/F (ratio of PaO2 to FiO2) in the RM group was significantly higher than in the CON group from 2 hrs after ALI inducement (P<0.05). Alveolar-to-arterial oxygen difference in the RM group was obviously lower compared with the CON group from 2 hrs after ALI inducement (P<0.05). The levels of TGF-ß1 in plasma and BALF and the mRNA expression of TGF-ß1 in the lung tissue were lower than in the CON group. Volume density of alveolar aeration in the RM group was significantly higher than in the CON group, and the injury score in the RM group was lower (P<0.05). CONCLUSIONS: RM can improve gas exchange and Cdyn in the treatment of piglets with ALI. RM is a safe and effective approach to alveolar recruitment and can alleviate ventilation induced lung injury.

Effect of continuous veno-venous hemodiafiltration on endotoxin-induced acute lung injury of the piglets.

OBJECTIVE: To evaluate the effect of continuous veno-venous hemodialysis filtration (CVVHDF) on cardiopulmonary function and clearance of inflammatory mediators in piglets with endotoxin-induced acute lung injury. DESIGN: A randomized controlled trial. SETTING: An animal laboratory in a tertiary care pediatric center. SUBJECTS: : Eighteen piglets, weighing 6-8 kg. INTERVENTIONS: The piglets were anesthetized, ventilated, and received an intravenous infusion of 150 µg/kg of endotoxin. They were then randomly divided into three groups: control group (n = 6) received Ringer's lactate solution; the heparin group (n = 6) received heparin infusion plus Ringer's lactate solution; and the CVVHDF group (n = 6) received CVVHDF plus heparin infusion and Ringer's lactate solution. MEASUREMENTS AND MAIN RESULTS: Parameters measured simultaneously were: heart rate, mean arterial blood pressure, central venous pressure, pulse contour cardiac index, cardiac function index, left ventricular contractile index, and systemic vascular resistance index; extra vascular lung water index, respiratory rate, dynamic pulmonary compliance, airway resistance, Pao2/Fio2 ratio, serum tumor necrosis factor-α, and soluble tumor necrosis factor receptor. Lung tissue was obtained for pathologic lung injury scoring and wet/dry weight ratio. Endotoxin challenge decreased oxygenation and pulmonary mechanics, suppressed cardiac function, increased extravascular lung water, and elevated serum inflammatory mediators (tumor necrosis factor-α and soluble tumor necrosis factor receptor). After CVVHDF, pulmonary function and oxygenation improved (Pao2/Fio2, 291.5 ± 75.9 vs. 217.2 ± 45.4, respectively, p < .05); arterial blood pressure and cardiac function were restored (pulse contour cardiac index, 3.95 ± 0.52 L/min/m(2) vs. 2.69 ± 0.49 L/min/m(2), respectively, p < .05); extravascular lung water decreased, and serum inflammatory markers also decreased. Lung injury score improved and wet/dry weight ratio decreased. CONCLUSION: Early CVVHDF has a beneficial effect on acute lung injury in piglets and is associated with a reduction in inflammatory cytokines, improving pulmonary function and hemodynamics and decreasing extravascular lung water and lung damage.

[Clinical analysis of recruitment maneuver with low tidal volume in the treatment of 15 children with acute lung injury].

OBJECTIVE: To determine the effects and feasibility of recruitment maneuver (RM) on children with acute lung injury (ALI), and to establish a more reasonable ventilation strategy in the treatment of pediatric ALI. METHOD: A prospective physiologic study was conducted in the Pediatric Intensive Care Unit (PICU). Fifteen consecutive eligible pediatric patients with ALI according to the 1994 AECC definition were enrolled in this study. The children received the ventilation of RM with low tidal volume. The clinician administered RM was performed at 30 cm H2O continuous positive airway pressure (CPAP) for 30 seconds. RMs were conducted once every eight hours for five days. Data on gas exchange, lung mechanics and hemodynamics from pre-RM to post-RM (at 5, 15, 30 and 60 min) was recorded at the first, third and fifth day. To monitor the pathogenic conditions of children, the radiographic examination was rechecked for every child within one week. At last, we documented the mortality and the length of ventilation of every patient. RESULT: On the first, third and fifth day, the P/F ratio of the patients was 243.8 mm Hg, 281.8 mm Hg and 309.9 mm Hg respectively, and significant improvements in oxygenation were demonstrated post-RM compared to pre-RM (P < 0.01). Cdyn [0.762 ml/(cm H2O×kg), 0.835 (ml/cm H2O×;kg), 0.928 ml/(cm H2O×kg)] before RMs also showed increase in the children on the first, third and fifth day (P < 0.01). Though there were some changes in blood pressure and heart rate following RM, no statistically significant changes were found during the course of RM. During the entire study of 5 days, all the 11 subjects whose chest radiograph showed infiltration had improvements, the length of ventilation was (10.15 ± 4.3) d. CONCLUSION: RM can significantly improve the oxygenation and attenuate the deterioration in pulmonary function in treatment for pediatric ALI and improve the lung compliance. It is safe and feasible.

The epidemiology of acute respiratory distress syndrome in pediatric intensive care units in China.

OBJECTIVE: To assess the incidence of, predisposing factors for, and the rates and relative risks of mortality from acute respiratory distress syndrome (ARDS) in pediatric patients. DESIGN: A prospective study in 12 consecutive months from 2004 to 2005 in 25 pediatric intensive care units (PICUs). PATIENTS AND SETTING: ARDS was diagnosed according to the 1994 American-European Consensus Conference definitions, applied to all severely ill admissions between 1 month and 14 years of age. The PICUs were in major municipalities and provincial cities, and half were university affiliated. MEASUREMENTS AND RESULTS: From a total of 12,018 admissions, 7,269 were severely ill. One hundred and five (1.44%) patients developed ARDS and 64 (61.0%) died, which accounts for 13.2%, of the total ICU death (n = 485, 6.7%) or a nine times relative risk of dying. The median age at onset of ARDS was 24 months and 40% were less than 12 month old. Median time from PICU admission to the onset of ARDS was 16 h, and in 63% <24 h. Pneumonia (55.2%) and sepsis (22.9%) were the major predisposing factors for ARDS. These were respectively 14 and 5 times as high a death rate as those of the severely ill patients without ARDS. CONCLUSIONS: ARDS has a high mortality in these Chinese PICUs, especially in those with pneumonia and sepsis, and adequate management including lung protective ventilation strategy is required.