Prenatal diagnosis and treatment for fetal angiotensin converting enzyme deficiency.

OBJECTIVE: To elucidate an etiology in a case with persistent oligohydramnios by prenatal diagnosis and actively treat the case to achieve good prognosis. METHODS: We performed whole exome sequencing (WES) of DNA from the fetus and parents. Serial amnioinfusions were conducted until birth. Pressors were required to maintain normal blood pressure. The infant angiotensin-converting enzyme (ACE) activity, angiotensin II (Ang II, a downstream product of ACE), and compensatory enzymes (CEs) activities were measured. Compensatory enzyme activities in plasma from age-matched healthy controls were also detected. RESULTS: We identified a fetus with a severe ACE mutation prenatally. The infant was born prematurely without pulmonary dysplasia. Hypotension and anuria resolved spontaneously. He had almost no ACE activity, but his Ang II level and CE activity exceeded the upper limit of the normal range and the upper limit of the 95% confidence interval of controls, respectively. His renal function also largely recovered. CONCLUSION: Fetuses with ACE mutations can be diagnosed prenatally through WES. Serial amnioinfusion permits the continuation of pregnancy in fetal ACE deficiency. Compensatory enzymes for defective ACE appeared postnatally. Renal function may be spared by preterm delivery; furthermore, for postnatal vasopressor therapy to begin, improving renal perfusion pressure before nephrogenesis has been completed.

[Effect of improvement in antibiotic use strategy on the short-term clinical outcome of preterm infants with a gestational age of <35 weeks]. / æŠ—ç”Ÿç´ ä½¿ç”¨ç­–ç•¥æ”¹è¿›å¯¹èƒŽé¾„<35周早产儿近期临床结局的影响.

OBJECTIVES: To study the effect of improvement in antibiotic use strategy on the short-term clinical outcome of preterm infants with a gestational age of <35 weeks. METHODS: The medical data were retrospectively collected from 865 preterm infants with a gestational age of <35 weeks who were admitted to the Neonatal Intensive Care Unit of Xiangya Hospital of Central South University from January 1, 2014 to December 31, 2016. The improved antibiotic use strategy was implemented since January 1, 2015. According to the time of implementation, the infants were divided into three groups: pre-adjustment (January 1, 2014 to December 31, 2014; n=303), post-adjustment Ⅰ (January 1, 2015 to December 31, 2015; n=293), and post-adjustment Ⅱ (January 1, 2016 to December 31, 2016; n=269). The medical data of the three groups were compared. RESULTS: There were no significant differences among the three groups in gestational age, proportion of small-for-gestational-age infants, sex, and method of birth (P>0.05). Compared with the pre-adjustment group, the post-adjustment I and post-adjustment Ⅱ groups had a significant reduction in the rate of use of antibiotics and the duration of antibiotic use in the early postnatal period and during hospitalization (P<0.05), with a significant increase in the proportion of infants with a duration of antibiotic use of ≤3 days or 4-7 days and a significant reduction in the proportion of infants with a duration of antibiotic use of >7 days in the early postnatal period (P<0.05). Compared with the post-adjustment Ⅰ group, the post-adjustment Ⅱ group had a significant reduction in the duration of antibiotic use in the early postnatal period and during hospitalization (P<0.05), with a significant increase in the proportion of infants with a duration of antibiotic use of ≤3 days and a significant reduction in the proportion of infants with a duration of antibiotic use of 4-7 days or >7 days (P<0.05). Compared with the pre-adjustment group, the post-adjustment I and post-adjustment Ⅱ groups had significantly shorter duration of parenteral nutrition and length of hospital stay (P<0.05). There were gradual reductions in the incidence rates of grade ≥Ⅲ intraventricular hemorrhage (IVH) and late-onset sepsis (LOS) after the adjustment of antibiotic use strategy. The multivariate logistic regression analysis showed that the adjustment of antibiotic use strategy had no effect on short-term adverse clinical outcomes, and antibiotic use for >7 days significantly increased the risk of adverse clinical outcomes (P<0.05). CONCLUSIONS: It is feasible to reduce unnecessary antibiotic use by the improvement in antibiotic use strategy in preterm infants with a gestational age of <35 weeks, which can also shorten the duration of parenteral nutrition and the length of hospital stay and reduce the incidence rates of grade ≥Ⅲ IVH and LOS.

D-bifunctional protein deficiency caused by HSD17B4 gene mutation in a neonate. / HSD17B4åŸºå› çªå˜è‡´D-双功能蛋白缺乏症.

A 15-day-old boy was admitted to the hospital due to repeated convulsions for 14 days. The main clinical manifestations were uncontrolled seizures, hypoergia, feeding difficulties, limb hypotonia, and bilateral hearing impairment. Clinical neurophysiology showed reduced brainstem auditory evoked potential on both sides and burst-suppression pattern on electroencephalogram. Measurement of very-long-chain fatty acids in serum showed that C26:0 was significantly increased. Genetic testing showed a pathogenic compound heterozygous mutation, c.101C>T(p.Ala34Val) and c.1448_1460del(p.Ala483Aspfs*37), in the HSD17B4 gene. This article reports a case of D-bifunctional protein deficiency caused by HSD17B4 gene mutation and summarizes the epidemiological and clinical features, diagnosis, and treatment of this disease, with a focus on the differential diagnosis of this disease from Ohtahara syndrome.

[The metabolic networks of ferroptosis and links to lung diseases].

Ferroptosis is a newly discovered non-apoptotic form of regulated cell death driven by iron-dependent lipid peroxidation. The present studies have shown that many metabolic processes and homeostasis are affected by ferroptosis. It is related to many lung diseases, including acute lung injury, chronic obstructive pulmonary disease and pulmonary fibrosis, etc. Currently, the research on ferroptosis is still in its infancy. Previous studies have confirmed that ferroptosis is regulated by a variety of genes, and the mechanism is complex, mainly involving iron homeostasis and lipid peroxidation metabolism. This review summarizes some regulation networks of metabolic processes associated with ferroptosis and discusses the roles of ferroptosis in the pathophysiological progression of many lung diseases. We expected to provide new ideas and references for the treatment of these diseases.

[Fetal pleural effusion in the uterus and dyspnea after birth].

Neonatal chylothorax is a common cause of neonatal congenital pleural effusion and is often caused by the accumulation of chylous fluid in the thoracic cavity due to the rupture of the thoracic duct and its branched lymphatic vessels for a variety of reasons. Neonatal chylothorax caused by malignant tumors is extremely rare, and this is the first case of neonatal mediastinal neuroblastoma with chylothorax in China. The boy was found to have pleural effusion in the left thoracic cavity in the uterus, and experienced apnea at birth, as well as dyspnea and cyanosis as the main manifestations after birth. He was diagnosed with left chylothorax based on conventional biochemical analysis of pleural effusion. After the treatment including persistent chest drainage and symptomatic and supportive treatment, the drainage of the left thoracic cavity reached a volume of 90-180 mL per day. Neonatal refractory chylothorax was considered. Chest radiograph on day 13 after birth showed lesions in the upper left lung field, and contrast-enhanced plain CT scan of the chest suggested the possibility of posterior mediastinal neuroblastoma. The autopsy confirmed giant posterior mediastinal neuroblastoma (poorly differentiated), which involved the C7-T6 spinal canal and the nearby erector spinae, with a small amount of tumor tissue in the liver and both adrenal glands. Mediastinal tumor is considered the underlying cause of chylothorax in this case.

[Comparison of the efficacy of domestic and imported caffeine citrate in the treatment of apnea in preterm infants: a prospective randomized double-blind controlled trial].

OBJECTIVE: To compare the efficacy of domestic and imported caffeine citrate in the treatment of apnea in preterm infants. METHODS: A total of 98 preterm infants with a gestational age of 28 - <34 weeks between April 2018 and December 2019 were enrolled. They were randomly administered with domestic (n=48) or imported caffeine citrate (n=50) within 6 hours after birth. The therapeutic effects, complications, adverse effects and clinical outcomes were compared between the two groups. RESULTS: There were no significant differences in the incidence of apnea within 7 days after birth, daily frequency of apnea, the time of apnea disappearance, the failure rate of intubation-surfactant-extubation strategy, the time of non-invasive assisted ventilation, the duration of oxygen therapy, the duration of caffeine citrate therapy, the length of hospital stay, blood gas analysis results, liver and kidney function testing results between the two groups (P>0.05). There were no significant differences in the incidence of complications and the mortality rate between the two groups (P>0.05). There was no significant difference in the incidence of adverse effects between the two groups (P>0.05). CONCLUSIONS: The efficacy and safety of domestic caffeine citrate in the treatment of apnea are similar to those of imported caffeine citrate in preterm infants.

[A multicenter survey of antibiotic use in very and extremely low birth weight infants in Hunan Province].

OBJECTIVE: To investigate the current status of antibiotic use for very and extremely low birth weight (VLBW/ELBW) infants in neonatal intensive care units (NICUs) of Hunan Province. METHODS: The use of antibiotics was investigated in multiple level 3 NICUs of Hunan Province for VLBW and ELBW infants born between January, 2017 and December, 2017. RESULTS: The clinical data of 1 442 VLBW/ELBW infants were collected from 24 NICUs in 2017. The median antibiotic use duration was 17 days (range: 0-86 days), accounting for 53.0% of the total length of hospital stay. The highest duration of antibiotic use was up to 91.4% of the total length of hospital stay, with the lowest at 14.6%. In 16 out of 24 NICUs, the antibiotic use duration was accounted for more than 50.0% of the hospitalization days. There were 113 cases with positive bacterial culture grown in blood or cerebrospinal fluid, making the positive rate of overall bacterial culture as 7.84%. The positive rate of bacterial culture in different NICUs was significantly different from 0% to 14.9%. The common isolated bacterial pathogens Klebsiella pneumoniae was 29 cases (25.7%); Escherichia coli 12 cases (10.6%); Staphylococcus aureus 3 cases (2.7%). The most commonly used antibiotics were third-generation of cephalosporins, accounting for 41.00% of the total antibiotics, followed by penicillins, accounting for 32.10%, and followed by carbapenems, accounting for 13.15%. The proportion of antibiotic use time was negatively correlated with birth weight Z-score and the change in weight Z-score between birth and hospital discharge (rs=-0.095, -0.151 respectively, P<0.01), positively correlated with death/withdrawal of care (rs=0.196, P<0.01). CONCLUSIONS: Antibiotics used for VLBW/ELBW infants in NICUs of Hunan Province are obviously prolonged in many NICUs. The proportion of routine use of third-generation of cephalosporins and carbapenems antibiotics is high among the NICUs.

Antenatal blockade of N-methyl-D-aspartate receptors by Memantine reduces the susceptibility to diabetes induced by a high-fat diet in rats with intrauterine growth restriction.

Intrauterine growth retardation (IUGR) is closely related to the later development of type 2 diabetes in adulthood. Excessive activation of N-methly-D-aspartate receptors (NMDARs) causes excitatory neurotoxicity, resulting in neuronal injury or death. Inhibition of NMDARs enhances the glucose-stimulated insulin secretion and survival of islet cells in type 2 diabetic mouse and human islets. Here, we examined whether antenatal blockade of NMDARs by Memantine could decrease the risk of diabetes induced by a high-fat (HF) diet at adulthood in IUGR rats. Pregnant SD rats were assigned to four groups: control, IUGR, Memantine, and Memantine + IUGR. The pregnant rats were exposed to hypoxic conditions (FiO2 = 0.105) for 8 h/day (IUGR group) or given a daily Memantine injection (5 mg/kg, i.p.) before hypoxia exposure from embryonic day (E) 14.5 to E 20.5 (Memantine + IUGR). The offspring were fed an HF diet with 60% of the calories from age 4 to 12 weeks. We found that NMDAR mRNAs were expressed in the fetal rat pancreas. An HF diet resulted in a high rate of diabetes at adulthood in the IUGR group. Antenatal Memantine treatment decreased the risk of diabetes at adulthood of rats with IUGR, which was associated with rescued glucose tolerance, increased insulin release, improved the insulin sensitivity, and increased expression of genes related to beta-cell function in the pancreas. Together, our results suggest that antenatal blockade of NMDARs by Memantine in pregnant rats improves fetal development and reduces the susceptibility to diabetes at adulthood in offspring.

[Methods for establishing animal model of bronchopulmonary dysplasia and their evaluation].

With the development of treatment, the survival rate of premature infants has significantly increased, especially extremely premature infants and very low birth weight infants. This has led to an increase in incidence of bronchopulmonary dysplasia (BPD) year by year. BPD has been one of the most common respiratory system diseases in premature infants, especially the small premature infants. Arrested alveolar development is an important cause of BPD. Therefore, the mechanism of arrested alveolar development and the intervention measures for promoting alveolar development are the focuses of research on BPD. Selecting the appropriate animal model of BPD is the key to obtaining meaningful results in the basic research on BPD. Based on above, several common methods for establishing an animal model of BPD and the corresponding changes in pathophysiology are summarized and evaluated in order to provide a reference for selecting the appropriate animal model in studies on the pathogenesis, pathophysiology, and prevention and control strategies of BPD.

[Effects of extensively hydrolyzed protein formula on feeding and growth in preterm infants: a multicenter controlled clinical study].

OBJECTIVE: To study the effects of extensively hydrolyzed protein formula (eHF) on the feeding and growth in preterm infants through a multicenter controlled clinical study. METHODS: Preterm infants admitted to eight upper first-class hospitals in China between February 2012 and December 2013 were randomly selected. They were divided into two observation groups and two control groups. The first observation group consisted of preterm infants with a gestational age of <32 weeks, who were fed with eHF for 10-14 days after birth and then with standard preterm formula (SPF) until discharge. The second observation group consisted of preterm infants with a gestational age of 32-34 weeks, who were fed with SPF after birth, but were switched to eHF (7-14 days) if suffering feeding intolerance at 6-8 days after birth. The two control groups with corresponding gestational ages kept to be fed with SPF after birth. Clinical data were recorded to compare feeding condition, physical growth, blood biochemical indices, and major complications between different groups. RESULTS: A total of 328 preterm infants were enrolled. Preterm infants with a gestational age of <32 weeks in the observation group had a significantly shorter meconium evacuation time than in the corresponding control group (P<0.05). They also had significantly lower levels of serum total bilirubin at weeks 1 and 2 after birth compared with the control group (P<0.05). The observation group needed more time in reaching enteral nutrition (EN) basic energy uptake of 50 kcal/(kg·d), partial parenteral nutrition (PPN), hospitalization, and corrected gestational age at discharge compared with the controlled infants (P<0.05). There was no difference in the incidence of extrauterine growth retardation (EUGR) at discharge between the two groups (P>0.05). Preterm infants with a gestational age of 32-34 weeks in the observation group had significantly lower serum total bilirubin levels at 2 weeks after birth compared with the corresponding control group (P<0.05). They required more time in achieving EN basic energy and PPN than in the control group (P<0.05). There was no difference in the incidence of EUGR at discharge between the two groups (P>0.05). CONCLUSIONS: For preterm infants, eHF can improve gastrointestinal motility, accelerate bilirubin metabolism and excretion and does not increase the incidence of EUGR.

NMDAR activation attenuates the protective effect of BM-MSCs on bleomycin-induced ALI via the COX-2/PGE2 pathway.

N-methyl-d-aspartate (NMDA) receptor (NMDAR) activation mediates glutamate (Glu) toxicity and involves bleomycin (BLM)-induced acute lung injury (ALI). We have reported that bone marrow-derived mesenchymal stem cells (BM-MSCs) are NMDAR-regulated target cells, and NMDAR activation inhibits the protective effect of BM-MSCs on BLM-induced pulmonary fibrosis, but its effect on ALI remains unknown. Here, we found that Glu release was significantly elevated in plasma of mice at d 7 after intratracheally injected with BLM. BM-MSCs were pretreated with NMDA (the selective agonist of NMDAR) and transplanted into the recipient mice after the BLM challenge. BM-MSCs administration significantly alleviated the pathological changes, inflammatory response, myeloperoxidase activity, and malondialdehyde content in the damaged lungs, but NMDA-pretreated BM-MSCs did not ameliorate BLM-induced lung injury in vivo. Moreover, NMDA down-regulated prostaglandin E2 (PGE2) secretion and cyclooxygenase (COX)-2 expression instead of COX-1 expression in BM-MSCs in vitro. We also found that NMDAR1 expression was increased and COX-2 expression was decreased, but COX-1 expression was not changed in primary BM-MSCs of BLM-induced ALI mice. Further, the cultured supernatants of lipopolysaccharide (LPS)-pretreated RAW264.7 macrophages were collected to detect inflammatory factors after co-culture with NMDA-pretreated BM-MSCs. The co-culture experiments showed that NMDA precondition inhibited the anti-inflammatory effect of BM-MSCs on LPS-induced macrophage inflammation, and PGE2 could partially alleviate this inhibition. Our findings suggest that NMDAR activation attenuated the protective effect of BM-MSCs on BLM-induced ALI in vivo. NMDAR activation inhibited COX-2 expression and PGE2 secretion in BM-MSCs and weakened the anti-inflammatory effect of BM-MSCs on LPS-induced macrophage inflammation in vitro. In conclusion, NMDAR activation attenuates the protective effect of BM-MSCs on BLM-induced ALI via the COX-2/PGE2 pathway. Keywords: Acute Lung Injury, BM-MSCs, NMDA receptor, COX-1/2, PGE2.

Antiflammin-1 attenuates bleomycin-induced pulmonary fibrosis in mice.

BACKGROUND: Antiflammin-1 (AF-1), a derivative of uteroglobin (UG), is a synthetic nonapeptide with diverse biological functions. In the present study, we investigated whether AF-1 has a protective effect against bleomycin-induced pulmonary fibrosis. METHODS: C57BL/6 mice were injected with bleomycin intratracheally to create an animal model of bleomycin-induced pulmonary fibrosis. On Day 7 and Day 28, we examined the anti-inflammatory effect and antifibrotic effect, respectively, of AF-1 on the bleomycin-treated mice. The effects of AF-1 on the transforming growth factor-beta 1 (TGF-ß1)-induced proliferation of murine lung fibroblasts (NIH3T3) were examined by a bromodeoxycytidine (BrdU) incorporation assay and cell cycle analysis. RESULTS: Severe lung inflammation and fibrosis were observed in the bleomycin-treated mice on Day 7 and Day 28, respectively. Administration of AF-1 significantly reduced the number of neutrophils in the bronchoalveolar lavage fluid (BALF) and the levels of tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1ß) in the lung homogenates on Day 7. Histological examination revealed that AF-1 markedly reduced the number of infiltrating cells on Day 7 and attenuated the collagen deposition and destruction of lung architecture on Day 28. The hydroxyproline (HYP) content was significantly decreased in the AF-1-treated mice. In vitro, AF-1 inhibited the TGF-ß1-induced proliferation of NIH3T3 cells, which was mediated by the UG receptor. CONCLUSIONS: AF-1 has anti-inflammatory and antifibrotic actions in bleomycin-induced lung injury. We propose that the antifibrotic effect of AF-1 might be related to its suppression of fibroblast growth in bleomycin-treated lungs and that AF-1 has potential as a new therapeutic tool for pulmonary fibrosis.

Sp1 mediated the inhibitory effect of glutamate on pulmonary surfactant synthesis.

BACKGROUND: Studies have shown that the release of endogenous glutamate (Glu) participates in lung injury by activating N-methyl-D-aspartate receptor (NMDAR), but the mechanism is still unclear. This study was to investigate the effects and related mechanisms of Glu on the lipid synthesis of pulmonary surfactant (PS) in isolated rat lung tissues. METHODS: The cultured lung tissues of adult SD rats were treated with Glu. The amount of [3H]-choline incorporation into phosphatidylcholine (PC) was detected. RT-PCR and Western blot were used to detect the changes of mRNA and protein expression of cytidine triphosphate: phosphocholine cytidylyltransferase alpha (CCTα), a key regulatory enzyme in PC biosynthesis. Western blot was used to detect the expression of NMDAR1, which is a functional subunit of NMDAR. Specific protein 1 (Sp1) expression plasmids were used. After transfected with Sp1 expression plasmids, the mRNA and protein levels of CCTα were detected by RT-PCR and Western blot in A549 cells. After treated with NMDA and MK-801, the mRNA and protein levels of Sp1 were detected by RT-PCR and Western blot in A549 cells. RESULTS: Glu decreased the incorporation of [3H]-choline into PC in a concentration- and time- dependent manner. Glu treatment significantly reduced the mRNA and protein levels of CCTα in lungs. Glu treatment up-regulated NMDAR1 protein expression, and the NMDAR blocker MK-801 could partially reverse the reduction of [3H]-choline incorporation induced by Glu (10-4 mol/L) in lungs. After transfected with Sp1 plasmid for 30 h, the mRNA and protein expression levels of CCTα were increased and the protein expression of Sp1 was also up-regulated. After A549 cells were treated with NMDA, the level of Sp1 mRNA did not change significantly, but the expression of nucleus protein in Sp1 was significantly decreased, while the expression of cytoplasmic protein was significantly increased. However, MK-801could reverse these changes. CONCLUSIONS: Glu reduced the biosynthesis of the main lipid PC in PS and inhibited CCTα expression by activating NMDAR, which were mediated by the inhibition of the nuclear translocation of Sp1 and the promoter activity of CCTα. In conclusion, NMDAR-mediated Glu toxicity leading to impaired PS synthesis may be a potential pathogenesis of lung injury.

[Activation of mGluRI in neutrophils promotes the adherence of neutrophils to endothelial cells].

L-glutamate (Glu) is an excitatory neurotransmitter in the mammalian central nervous system. Relatively much attention has been paid to functional expression of Glu signaling molecules in peripheral tissues very recently. The present study tested the hypothesis that the activation of group I metabotropic glutamate receptor (mGluRI) in neutrophils stimulated neutrophils adherence to endothelial cells by increasing the surface expression of certain adhesion molecules. Peripheral blood was obtained by venipuncture from healthy donors, and the neutrophils were isolated by Ficoll-Hypaque gradient centrifugation. Neutrophils floating into DMEM/F12 culture medium containing 10% fetal bovine serum were then used immediately. Immunocytochemistry and real-time quantitative RT-PCR were used to detect the expression of mGluRI (mGluR1 and mGluR5) in neutrophils. The adherence of neutrophils to cultured human normal umbilical vein endothelial cells (HUVE-12) was measured by the colorimetric method. Cell surface expression of adhesion molecule CD11a in the neutrophils was determined by flow cytometry. Immunocytochemistry and real-time quantitative RT-PCR showed that mGluR1 and mGluR5 were constitutively expressed in neutrophils. Application of mGluRI agonist S-3,5-dihydroxyphenylglycine (S-DHPG) (1x10(-8)-1x10(-6) mol/L) showed a dose-dependent stimulatory effect on the adherence of neutrophils to HUVE-12 (P<0.05 or P<0.01), with a maximum effect at 1x10(-6) mol/L (P<0.01). Incubations as short as 30 min were sufficient to induce increased adherence after the beginning of S-DHPG treatment. Following time extension (0.5-5 h), S-DHPG (1x10(-6) mol/L) increased the rate of neutrophils adhesion to HUVE-12 with a maximum effect at 0.5 h (P<0.01). However, a time-dependent effect of S-DHPG on the rate of neutrophils adhesion to HUVE-12 was not observed during the experimental period. 1x10(-6) mol/L of S-DHPG also induced an increased surface expression of adhesion molecule CD11a (P<0.01) when neutrophils were preincubated with 1x10(-6) mol/L of S-DHPG for 1 h. Furthermore, the specific mGluRI antagonist (RS)-alpha-methyl-4-carboxyphenylglycine ((+/-)-MCPG, 0.5 mmol/L) significantly abolished the stimulatory effect of S-DHPG (1x10(-6) mol/L) on the adherence of neutrophils to HUVE-12 (P<0.01). These results suggest that the activation of mGluRI in neutrophils results in increased adhesion molecule CD11a expression and thereby promotes the adherence of neutrophils to endothelial cells.

G-CSF Inhibits Pulmonary Fibrosis by Promoting BMSC Homing to the Lungs via SDF-1/CXCR4 Chemotaxis.

Bone marrow mesenchymal stem cells (BMSCs) have multi-lineage differentiation potential and play an important role in tissue repair. Studies have shown that BMSCs gather at the injured tissue site after granulocyte-colony stimulating factor (G-CSF) administration. In this study, we first investigated whether G-CSF could promote BMSC homing to damaged lung tissue induced by bleomycin (BLM) and then investigated whether SDF-1/CXCR4 chemotaxis might be involved in this process. Next, we further studied the potential inhibitory effect of G-CSF administration in mice with lung fibrosis induced by bleomycin. We examined both the antifibrotic effects of G-CSF in mice with bleomycin-induced pulmonary fibrosis in vivo and its effects on the proliferation, differentiation and chemotactic movement of cells in vitro. Flow cytometry, real-time PCR, transwell and Cell Counting Kit-8 (CCK-8) assays were used in this study. The results showed that both preventative and therapeutic G-CSF administration could significantly inhibit bleomycin-induced pulmonary fibrosis. G-CSF enhanced BMSC migration to lung tissues, but this effect could be alleviated by AMD3100, which blocked the SDF-1/CXCR4 axis. We also found that BMSCs could inhibit fibroblast proliferation and transdifferentiation into myofibroblasts through paracrine actions. In conclusion, G-CSF exerted antifibrotic effects in bleomycin-induced lung fibrosis, in part by promoting BMSC homing to injured lung tissues via SDF-1/CXCR4 chemotaxis.

[MRI diagnosis of cerebral sparganosis in children].

OBJECTIVE: To study the value of MRI in the diagnosis of cerebral sparganosis in children. METHODS: The MRI appearances of 17 children with cerebral sparganosis proven by pathology or serological test were retrospectively studied. The diagnostic accuracy rate of cerebral sparganosis was compared before and after knowing the imaging features of this disease. RESULTS: Enhanced MRI was performed in 12 cases, and all of them demonstrated abnormal enhancement. Peripheral ring-type, tortuous beaded shape or serpiginous tubular shape enhancement were found in 8 cases. After analysis of follow-up MRI for 7 cases, a change in location and shape of lesions was found in 2 cases. Typical MRI patterns of cerebral sparganosis included abnormal enhancement such as peripheral ring-type, tortuous beaded shape or serpiginous tubular shape enhancement, and changes in location and shape of lesions in the follow-up MRI. The diagnostic accuracy rate for the 17 cases of cerebral sparganosis at the first visit, after first imaging examination and after several follow-up MR examinations were 0%, 11.8% and 28.6%, respectively. The diagnostic accuracy rate of this disease increased to 64.7%, 70.6% and 85.7% respectively after the radiologists were trained in the imaging characteristics of the disease. CONCLUSIONS: MR findings in children with cerebral sparganosis are specific. Mastering correctly the typical imaging features of the disease can be very helpful in reducing the rate of clinical misdiagnosis.

Role of c-fos gene in vasoactive intestinal peptide promoted synthesis of pulmonary surfactant phospholipids.

We previously reported that vasoactive intestinal peptide (VIP) promoted synthesis of phosphatidylcholine (PC) in alveolar type II (ATII) cells. But the intracellular mechanism for this effect was unknown. In this work, we investigated the intracellular signal transduction pathway for VIP promoted synthesis of PC, the major lipid component of pulmonary surfactant (PS), by using an antagonist of VIP receptors, inhibitor of protein kinase C (PKC) and antisense oligonucleotides (AS-ODN) for c-fos oncogene. Our results showed that: 1 in circle [D-P-Cl-Phe(6)-Leu(17)]-VIP (10(-6) mol/l), an antagonist of VIP receptors, could decrease the quantity of [(3)H] choline incorporation, microsomal choline-phosphate cytidylyltransferase (CCT) mRNA expression and CCT activity induced by VIP (10(-8) mol/l) in cultured lung explants to the control levels; 2 in circle VIP (10(-8) mol/l) upregulated c-Fos protein expression in ATII cells. AS-ODN for c-fos oncogene (9x10(-6) mol/l) could block the elevation of [(3)H] choline incorporation, microsomal CCT mRNA expression and CCT activity induced by VIP in cultured lung explants and in ATII cells; 3 in circle H7 (10(-5) mol/l), a PKC inhibitor could also reduce VIP induced [(3)H] choline incorporation, microsomal CCT mRNA expression and CCT activity in cultured lung explants and in ATII cells. These results demonstrated that VIP receptors, PKC and c-Fos protein played important roles in the signaling pathway through which VIP promoted the synthesis of PC.

[Experimental study of acute lung injury induced by glutamate in vivo].

OBJECTIVE: To investigate the possible injury induced by glutamate in the lung. METHODS: The lung wet weight/body weight (LW/BW), lung wet/dry weight (W/D), the content of cells and the total protein (TP) in bronchoalveolar lavage fluid (BALF) were determined together with the micromorphology observation. RESULTS: (1) The LW/BW, W/D, the content of white blood cells, red blood cells and TP in BALF increased in a dose dependent manner 2 hours after the administration of the glutamate (0.50 - 0.75 g/kg). (2) Examination of histological sections showed the presence of lung inflammation charactered by neutrophils recruitment 2 hours after the glutamate administration. (3) The increase of W/D caused by glutamate (0.50 g/kg) was nearly abolished by pre-treatment with MK801 (a specific blocker of NMDA receptor, 0.1 mg/kg) for 30 minutes (P<0.05). CONCLUSION: Glutamate can cause the acute lung injury through the activation of NMDA receptor in vivo.

A Sustained Activation of Pancreatic NMDARs Is a Novel Factor of ß-Cell Apoptosis and Dysfunction.

Type 2 diabetes, which features ß-cell failure, is caused by the decrease of ß-cell mass and insulin secretory function. Current treatments fail to halt the decrease of functional ß-cell mass. Strategies to prevent ß-cell apoptosis and dysfunction are highly desirable. Recently, our group and others have reported that blockade of N-methyl-d-aspartate receptors (NMDARs) in the islets has been proposed to prevent the progress of type 2 diabetes through improving ß-cell function. It suggests that a sustained activation of the NMDARs may exhibit deleterious effect on ß-cells. However, the exact functional impact and mechanism of the sustained NMDAR stimulation on islet ß-cells remains unclear. Here, we identify a sustained activation of pancreatic NMDARs as a novel factor of apoptotic ß-cell death and function. The sustained treatment with NMDA results in an increase of intracellular [Ca2+] and reactive oxygen species, subsequently induces mitochondrial membrane potential depolarization and a decrease of oxidative phosphorylation expression, and then impairs the mitochondrial function of ß-cells. NMDA specifically induces the mitochondrial-dependent pathway of apoptosis in ß-cells through upregulation of the proapoptotic Bim and Bax, and downregulation of antiapoptotic Bcl-2. Furthermore, a sustained stimulation of NMDARs impairs ß-cell insulin secretion through decrease of pancreatic duodenal homeobox-1 (Pdx-1) and adenosine triphosphate synthesis. The activation of nuclear factor-κB partly contributes to the reduction of Pdx-1 expression induced by overstimulation of NMDARs. In conclusion, we show that the sustained stimulation of NMDARs is a novel mediator of apoptotic signaling and ß-cell dysfunction, providing a mechanistic insight into the pathological role of NMDARs activation in diabetes.