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Objective:To analyze the status of neonatal respiratory distress syndrome (RDS) management in 10 hospitals in Northwest China over the past five years and to investigate the strategies for improving the prevention and treatment of RDS.Methods:This retrospective study involved premature infants with RDS who were admitted to the neonatal intensive care units (NICU) of 10 hospitals (six in Shaanxi Province, three in Gansu Province, and one in Xinjiang Uygur Autonomous Region) of the Northwest China Neonatal Collaborative Group within 3 d after birth from January 1 to December 31, 2016, and from January 1 to December 31, 2021. Basic information, perinatal condition, treatment approaches, complications, and prognosis of the patients were compared. T-test, rank sum, and Chi-square tests were used for statistical analysis. Result:(1) This study enrolled 322 premature infants with RDS in 2016 and 349 in 2021. Premature infants at the gestational age of 30 to 33 weeks were mainly affected, and the majority were male [64.3% (207/322) and 57.3% (200/349)]. The average maternal age in 2021 was older than that in 2016 [(30.6±4.8) years vs (28.6±5.4) years, t=24.02, P<0.001], and the proportion of women at advanced maternal age was also higher in 2021 [19.2% (67/349) vs 12.4% (40/322), χ2=4.18, P<0.05]. (2) The proportions of pregnancies conceived with assisted reproductive technologies [11.7% (41/349) vs 1.9% (6/322), χ2=25.12], underwent routine prenatal examinations [58.5% (204/349) vs 30.4% (98/322), χ2=53.33], exposed to steroids [62.2% (217/349) vs 28.6% (92/322), χ2=82.58] and delivered by cesarean section or elective cesarean section [73.6% (257/349) vs 51.6% (166/322), χ2=35.06; 24.1% (84/349) vs 6.5% (21/322), χ2=39.07], as well as the ratio of cesarean scar pregnancy [7.4% (26/349) vs 3.4% (11/322), χ2=5.23] were all higher in 2021 than those in 2016 (all P<0.05). Moreover, the incidence of fetal distress [30.1% (105/349) vs 20.2% (65/322), χ2=8.68], gestational hypertension [24.6% (86/349) vs 13.0% (42/322), χ2=14.59], premature rupture of membranes [16.0% (56/349) vs 10.2% (33/322), χ2=4.89], meconium-stained amniotic fluid [12.6% (44/349) vs 5.6% (18/322), χ2=9.83], placental abruption [10.3% (36/349) vs 5.3% (17/322), χ2=5.84], gestational diabetes mellitus [10.3% (36/349) vs 1.6%(5/322), χ2=22.41], chorioamnionitis [4.6%(16/349) vs 0.9% (3/322), χ2=8.12], thyroid dysfunction [4.3% (15/349) vs 0.6% (2/322), χ2=7.88] and heart disease [4.3% (15/349) vs 0.3% (1/322), χ2=9.17] were higher in 2021 than in 2016 (all P<0.05). (3) In 2021, the rate of pulmonary surfactant (PS) usage, the dosage of porcine PS, and the proportion of bovine PS usage were all significantly higher than those in 2016 [73.6% (257/349) vs 67.1% (216/322), χ2=11.62; (178.5±38.0) mg/kg vs (165.2±42.8) mg/kg, t=7.85; 47.9% (123/257) vs 19.4% (42/216), χ2=41.72; all P<0.01]. No significant difference in the incidence of intubation-surfactant-extubation (INSURE), early PS administration (≤2 h after birth), or the arterial blood gas values before and after PS treatment was found between the cases enrolled in 2021 and 2016. The duration of antibiotic treatment [7.0 d (5.0-14.0 d) vs 5.0 d (1.0-8.0 d), Z=7.55] and assisted ventilation [144 h (81-264 h) vs 73 h (47-134 h), Z=8.20] and the median hospital stay [24 d(14-42 d) vs 16 d (10-25 d), Z=6.74] were significantly longer in 2021 than in 2016 (all P<0.01). More patients required nasal intermittent positive pressure ventilation [29.6% (100/338) vs 1.0% (3/306), χ2=97.81] and conventional ventilation [42.6% (144/338) vs 30.1% (92/306), χ2=10.87] in 2021 as compared with those five years ago (both P<0.01). (4) In 2021, the incidence of patent ductus arteriosus [15.5% (54/349) vs 6.2% (20/322), χ2=63.40], bronchopulmonary dysplasia [9.2% (32/349) vs 2.8% (9/322), χ2=12.88], persistent pulmonary hypertension [5.4% (19/349) vs 0.6% (2/322), χ2=12.85], periventricular leukomalacia [4.3% (15/349) vs 1.2% (4/322), χ2=7.52] and pneumothorax [3.4% (12/349) vs 0.3% (1/322), χ2=9.68] increased as compared with those in 2016 (all P<0.05), while the incidence of nosocomial infection decreased significantly [7.4% (26/349) vs 19.6% (63/322), χ2=21.37, P<0.001]. (5) The cure rate of premature infants with RDS was 70.8% (247/349) in 2021, which was significantly higher than that in 2016 [56.2% (181/322), χ2=15.37, P<0.001]. Moreover, the rate of withdrawing treatment and the total mortality rate was lower in 2021 than in 2016 [7.7% (27/349) vs 14.3% (46/322), χ2=7.41; in-hospital: 1.4% (5/349) vs 5.6% (18/322), χ2=8.74; out of hospital: 8.3% (29/349) vs 13.7% (44/322), χ2=4.96; all P<0.05]. Conclusions:The clinical management of RDS in premature infants in the involved hospitals has been improved. However, there is room for improvement in prenatal examinations.
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Objective:To study the relationship between white matter injury (WMI) and brain maturity in preterm infants at full-term corrected gestational age (cGA).Methods:A retrospective study was performed in preterm infants [GA≤32 weeks or birth weight (BW) ≤1 500 g] admitted to the neonatal intensive care unit of the First Affiliated Hospital of Xi'an Jiaotong University from January 2017 to August 2018 and the Northwest Women and Children's Hospital from January 2017 to June 2017. The infants received conventional magnetic resonance imaging (MRI) at cGA 37~42 weeks. The infants were assigned into the WMI group and the control group according to the WMI scoring system, including the total maturation scores (TMS) and four sub-item scores.Results:A total of 118 premature infants were enrolled in this study (17 cases in the WMI group and 101 cases in the control group). The GA was (30.3±1.7) weeks, and BW was (1 356±268) g. The proportion of delayed TMS in the WMI group was significantly higher than the control group [58.8%(10/17) vs. 31.7%(32/101), P<0.05]. The TMS of the WMI group were significantly lower than the control group [(10.7±1.8) vs. (11.8±1.5), P<0.05]. The sub-item scores of TMS showed that the myelination [(2.8±0.6) vs. (3.1±0.4), P<0.05] and glial cell migration bands of the WMI group [(1.6±0.4) vs. (2.1±0.6), P=0.004] were significantly lower than the control group and no significant differences existed in cortical folding and involution of germinal matrix tissue scores between the two groups. Conclusions:The brain maturity of preterm infants with WMI is substantially delayed than those without WMI, including delayed myelination and delayed disappearance of glial cell migration bands.
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The First Affiliated Hospital of Xi'an Jiaotong University has established pediatric MOOCs courses, including the formation of excellent MOOC teachers, the curriculum planning and design of MOOCs, making MOOCs videos, and using MOOCs for teaching activities. The MOOCs for teaching is intuitive, the courses are interesting, and the learning time is flexible. Besides, it is open and resources-sharing, and it also can increase the educational equity. At the same time, it can reduce teachers' burden, improve teaching ability, and improve learning ability of students. Most students and teachers agree that MOOCs are worthy of promotion and application.
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OBJECTIVE@#To determine the association of circular RNA (circRNA) and circRNA-microRNA (miRNA) network regulation with brain injury induced by inflammation in preterm mice.@*METHODS@#Pregnant mice were treated with intraperitoneally injected lipopolysaccharide to establish a preterm mouse model of brain injury induced by inflammation (inflammation preterm group with 3 mice). Preterm mice born to normal pregnant mice by cesarean section were selected as controls (non-inflammation preterm group with 3 mice). The gene microarray technique was used to screen out the circRNAs associated with brain injury in preterm mice. The miRNA target prediction software was used to predict the binding sites between circRNAs and miRNAs and analyze the regulatory mechanism.@*RESULTS@#A total of 365 differentially expressed circRNAs were screened out between the inflammation preterm and non-inflammation preterm groups (fold change > 1.5, @*CONCLUSIONS@#Inflammation induces a significant change in the expression profile of circRNAs in the brain tissue of mice, and the change in the expression of circRNAs plays an important role in brain injury induced by inflammation and subsequent brain development in preterm mice.
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Animals , Female , Mice , Pregnancy , Brain Injuries , Cesarean Section , Gene Expression Profiling , Inflammation/genetics , MicroRNAs/genetics , RNA/genetics , RNA, CircularABSTRACT
OBJECTIVE@#To study the association of neonatal blood calcium levels with perinatal factors and neonatal urinary calcium levels measured by an intelligent urine test system.@*METHODS@#The medical data of 96 full-term singleton neonates with mild diseases were collected by a cross-sectional survey, who were hospitalized in the Department of Neonatology, The First Affiliated Hospital of Xi'an Jiaotong University, from June to August 2018. Urinary calcium levels measured by an intelligent urine test system, total blood calcium levels, ionized calcium levels, and the mother's calcium and vitamin D supplementation during pregnancy were recorded.@*RESULTS@#Compared with the group without vitamin D supplementation for the mother (17 neonates), the group with vitamin D supplementation for the mother (79 neonates) had significantly higher levels of total blood calcium and ionized calcium (@*CONCLUSIONS@#Vitamin D supplementation during pregnancy can increase the blood levels of total calcium and ionized calcium in neonates, and calcium supplementation alone cannot increase the blood levels of total calcium or ionized calcium in neonates. Hypothermia in neonates might cause the reduction in blood calcium levels. The urinary calcium level measured by the intelligent urine test system is positively correlated with the blood level of ionized calcium.
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Female , Humans , Infant, Newborn , Pregnancy , Calcium , Calcium, Dietary , Cross-Sectional Studies , Vitamin D , Vitamin D DeficiencyABSTRACT
Objective:To explore whether interactive learning mode can improve learning ability of medical students.Methods:From September 2017 to January 2018, there were 266 medical undergraduate interns of Grade 2014 in the department of pediatrics of the First Affiliated Hospital of Xi'an Jiaotong University. Interactive approach mode was used in pediatric probation teaching of hematological disease. And the questionnaire and final exam grade were used to evaluate the effect of interactive approach in pediatric clinical practice teaching and understand students' satisfaction with interactive learning. The test results were compared with those of 146 Grade 2013 students, who studied in the same period of 2016 and adopted traditional teaching methods. Data were analyzed using SPSS 19.0 software.Results:In the questionnaire survey, the interactive approach mode was believed to improve the learning enthusiasm by 95.8% (230/240) students, improve the ability of language expression by 97.5% (234/240) students, promote the knowledge understanding and memory by 93.3% (224/240) students, and enhance the ability of self-study and by 90.9% (218/240) students. Additionally, the mode was believed to facilitate the ability of analyzing and resolving problems by 94.2% (226/240) students, and enhance the ability of information technology, such as information retrieval ability, PPT production ability, by 96.2% (231/240) students. Moreover, the test results of students using interactive approach model mode were significantly higher than those using traditional teaching mode ( P<0.01). In the questionnaire survey, there were 92.5% (222/240) students accepting interactive approach mode. Conclusion:The teaching mode of interactive approach can improve the learning enthusiasm and learning ability of medical students, which is worthy of popularization and application in the probationary courses.
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OBJECTIVE@#To compare intranasal midazolam and intramuscular phenobarbital sodium for their sedative effect in neonates undergoing magnetic resonance imaging (MRI).@*METHODS@#A total of 70 neonates who underwent cranial MRI from September 2017 to March 2019 were randomized into an observation group and a control group, with 35 cases in each group. The observation group received intranasal drops of midazolam (0.3 mg/kg), and the control group received intramuscular injection of phenobarbital sodium (10 mg/kg). The sedation status of the neonates was evaluated using the Ramsay Sedation Scale. Meanwhile, the two groups were compared for the success rate of MRI procedure and incidence of adverse reactions.@*RESULTS@#In the observation group, the sedation score was the highest at 20 minutes post administration, then was gradually decreasing, and decreased to the lowest level at 70 minutes post administration. In the control group, the sedation score was the lowest at 10 minutes post administration, then was gradually increasing, and increased to the highest level at 40 minutes and 50 minutes post administration, followed by a gradual decrease. Comparison of the sedation score at each time period suggested that the sedation score was significantly higher in the observation group than in the control group within 40 minutes post administration (P0.05). The success rate of MRI procedure was significantly higher in the observation group than in the control group (89% vs 69%, P0.05).@*CONCLUSIONS@#Intranasal midazolam is superior to intramuscular phenobarbital sodium in the sedative effect in neonates undergoing MRI, with the benefits of being fast, convenient, safe, and effective.
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Humans , Infant, Newborn , Hypnotics and Sedatives , Pharmacology , Magnetic Resonance Spectroscopy , Midazolam , Prospective Studies , Single-Blind MethodABSTRACT
Objective To study the relationship between aquaporin 9 (AQP 9) gene and brain edema in neonatal rats of hypoxic-ischemic brain damage (HIBD) and the therapeutic mechanism of mannitol.Method Healthy and 7-day-old SD rats were randomly assigned into three groups:sham-operated group,HIBD group and mannitol group.Both HIBD and mannitol group were established on HIBD model.The mannitol group was given mannitol intraperitoneally at 0,24,48 h of HIBD.2 ml/kg of 2％ Evans blue (EB) were injected intraperitoneally before sacrifice.0,6,12,24,48 and 72 h after HIBD,the outcomes were analyzed including the brain water content,the expression of AQP 9 mRNA measured using RT-PCR and immunofluorescence staining methods,and the permeability of blood-brain barrier (BBB) measured with EB.Result In HIBD group,the brain water content was higher comparing with sham-operated group at 0 h after HIBD(P ＜ 0.05),and gradually increased over time,reaching peak at 48 h (89.3％ ± 1.9％) and then decreased.In mannitol group,brain water content started to decrease from 1 h after mannitol administration to the bottom at 12 h (86.5％ ±0.6％),then increased to peak at 72 h (87.2％ ± 1.7％),and brain water content were decreased during 0 ～ 48 h comparing with HIBD group.HIBD group's EB were higher than sham-operated group (P ＜ 0.05);Mannitol group's EB were decreased comparing with HIBD group (except 0 h,P ＜ 0.05).AQP 9 mRNA expression in the HIBD group was decreased at 0 h,and reached the bottom at 48 h (0.09 ± 0.07).Comparing with sham-operated group,it was higher in the HIBD group at0,6,72 h,and lower (P＜ 0.05) at 12,24,48 h.Higher AQP 9 mRNA expression were detected in mannitol group than HIBD group and sham-operated group at each time point (with the exception of 48 h) (P ＜ 0.05).AQP 9,which was closely related to water metabolism,were widely found in the pia mater and ependyma using immunofluorescence staining.After ischemia and hypoxia insult,an increasedecrease-increase pattern of AQP 9 expression was found.Conclusion AQP 9 is widely existed in various parts of the brain,influencing brain edema through a variety of pathways.AQP 9 also plays a role in alleviating brain edema in mannitol therapy.
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<p><b>OBJECTIVE</b>To study the influence of acute pancreatitis in pregnancy (APIP) on pregnancy outcomes and neonates.</p><p><b>METHODS</b>A retrospective analysis was performed for 33 APIP patients and 31 neonates born alive.</p><p><b>RESULTS</b>Of the 33 APIP patients, 26 (79%) developed APIP in the late pregnancy. Fourteen (45%) patients had hyperlipidemic APIP, 13 (42%) had biliary APIP, and 4 (13%) had other types of APIP. According to the severity, 22 (67%) were mild APIP, 5 (15%) were moderate APIP, and 6 were severe APIP. None of the 33 APIP patients died. Among the 20 patients with term delivery, 11 underwent termination of pregnancy; among the 10 patients with preterm delivery, 9 underwent termination of pregnancy; two patients experienced intrauterine fetal death, and one experienced abortion during the second trimester. Among the 31 neonates born alive (two of them were twins), 1 (3%) died, 12 (39%) experienced neonatal hyperbilirubinemia, 8 (26%) had neonatal hypoglycemia, 6 (19%) had neonatal respiratory distress syndrome, 5 (16%) experienced infectious diseases, and 2 (6%) experienced intracranial hemorrhage. The hyperlipidemic APIP group had a higher percentage of patients undergoing termination of pregnancy than the biliary APIP and other types of APIP groups (P<0.05). The incidence rate of preterm infants in the moderate APIP was higher than in the mild and severe APIP groups (P<0.05). The mean birth weights of neonates were the lowest in the moderate APIP group. The incidence rates of neonatal respiratory distress syndrome, intracranial hemorrhage, and infectious disease were the lowest in the mild APIP group (P<0.05).</p><p><b>CONCLUSIONS</b>APIP can lead to adverse pregnancy outcomes and neonatal diseases, which are associated with the severity of pancreatitis.</p>
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Female , Humans , Infant, Newborn , Male , Pregnancy , Acute Disease , Birth Weight , Infant, Premature , Pancreatitis , Pregnancy Complications , Retrospective StudiesABSTRACT
<p><b>OBJECTIVE</b>To investigate the association between long non-coding RNAs (lncRNAs) and brain injury in inflammation-induced preterm mice, and to provide a reference for the prevention and treatment of brain injury.</p><p><b>METHODS</b>An intraperitoneal injection of lipopolysaccharide in pregnant mice was performed to establish a model of inflammation-induced preterm mice with brain injury (preterm group). The full-term mice delivered by normal pregnant mice were used as controls (full-term group). The lncRNA chip assay was used to screen out the lncRNAs associated with brain injury in preterm mice. Quantitative real-time PCR was used to validate the lncRNAs identified by the above method.</p><p><b>RESULTS</b>The preterm and full-term groups showed significant differences in the expression of 1 978 lncRNAs (P<0.05), consisting of 786 up-regulated lncRNAs and 1 192 down-regulated lncRNAs, and 29 lncRNAs were 1.5 or more times differentially expressed between the two groups. A further analysis was performed for the 10 most differentially expressed lncRNAs, and the results showed that these lncRNAs were involved in the biological processes including transcription, signal transduction, apoptosis, cell cycle, and inflammatory response, as well as G protein-coupled receptor signaling pathway and neuropeptide signaling pathway. Real-time PCR was performed to validate the expression of two lncRNAs in brain tissue in the preterm and full-term groups, and the results were consistent with those of the chip assay.</p><p><b>CONCLUSIONS</b>The expression profiles of lncRNAs in brain tissue change significantly in inflammation-induced preterm mice, and the G protein-coupled receptor signaling pathway may be involved in the pathogenesis of preterm brain injury.</p>
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Animals , Female , Mice , Brain , Metabolism , Inflammation , Metabolism , Mice, Inbred BALB C , RNA, Long Noncoding , Receptors, G-Protein-Coupled , Physiology , Signal Transduction , PhysiologyABSTRACT
Background and purpose:Single drug of docetaxel and pemetrexed as second line treatment is standard treatment of advanced non-small cell lung cancer (NSCLC). Whether combined with platinum can increase the response and survival is still not elucidated. This study was designed to investigate the treatment response, overall survival (OS) and the safety of combined with oxaliplatin or cisplatin regimens as second line in treating NSCLC patients. Methods:Advanced NSCLC inpatients, failure of cisplatin or carboplatin in initial treatment, were divided into three groups at random in 3∶2∶1 rate. Control group:who received docetaxel, 75 mg/m2 (for all patients), d1 or pemetrexed 500 mg/m2 (for non-squamous carcinoma);Cisplatin group:who received cisplatin 25 mg/m2, d1-3 and docetaxel/pemetrexed; Oxaliplatin group: who received oxaliplatin 130 mg/m2 d1 and docetaxel/pemetrexed. Every 3 weeks were repeated as one cycle. The side effect was assessed every cycle and treatment efifcacy was investigated every two cycles. Follow-up examination was taken every 3 months after treatment. Results:There were no differences in treatment response, progress free survival (PFS), OS and toxicity among the three groups (P>0.05). Old patients (≥60 years) had a better PFS than that of patients less than 60 years (HR=0.56, 95%CI:0.35-0.90, P=0.015). Patients with performance score 0-1 had a better PFS and OS (HR=1.52, 95%CI:1.01-2.30, P=0.048;HR=1.90, 95%CI:1.17-3.09, P=0.009). Treatment response had relation to PFS and OS (HR=2.93, 95%CI:2.01-4.26, P=0.000;HR=2.03, 95%CI:1.37-3.01, P=0.000). Patients with anemia after treatment tended to have a worse PFS and OS (HR=1.59, 95%CI:0.97-2.61, P=0.066;HR=1.60, 95%CI:0.94-2.75, P=0.085). Patients with thrombocytopenia after therapy had a worse OS (HR=2.97, 95%CI:1.01-8.78, P=0.049). Patients with neural toxicity after chemotherapy tended to have a worse PFS (HR=3.36, 95%CI:0.92-12.25, P=0.066). Patients received post treatment after second line therapy had a better OS (HR=0.36, 95%CI:0.22-0.61, P=0.000). Conclusion:Combined with oxaliplatin or cisplatin as second line treatment can’t improve the response and survival in NSCLC patient. Treatment response and PS are prognostic factors to NSCLC patients’ PFS and OS. Patients with treatment related anemia might have a worse survival. Post therapy after failure to second line chemotherapy can prolong the survival.
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<p><b>OBJECTIVE</b>To detect possible relationship between genetic defect within the gene encoding member A3 of the ATP Binding Cassette family (ABCA3) and neonatal respiratory distress syndrome (NRDS), thus to understand the genetic mechanisms of NRDS in Han ethnic group.</p><p><b>METHOD</b>The clinical data of 11 cases with NRDS hospitalized in neonatal intensive care unit was investigated. Blood samples were collected from 11 cases with NRDS and 97 unassociated normal individuals. Polymerase chain reaction (PCR) and DNA direct sequencing were performed to screen all exons and their flanking introns of ABCA3 gene for mutation analysis in 11 cases with NRDS. If a new missense variation was identified, single strand conformation polymorphism analysis was performed in 97 healthy controls. Lung tissue sample from a case who died 12 hours after birth was examined with light microscopy and electron microscopy.</p><p><b>RESULT</b>Three missense genetic variants in exons, which include c. 2169 G > A (p.M723I), c. 1010 T > G (p.V337G), c. 4972 A > G (p.S1658G), one splice junction site variation (Exon 30 + 2 T/G), several unreported polymorphism sites [213 C > T(p.F71F), exon 21 + 34C/T] and reported polymorphism site (p.F353F) were identified on ABCA3 gene coding region in 11 case. The homozygous variation (c.2169G > A), which was in exon 17 and causes an M723I amino acid change, was found in the case who died 13 hours after birth, but not detected in 97 controls, indicating that this variation is indeed a mutation and not a polymorphism. In the case carrying c.2169G > A, ultrastructural examination of the alveolar type II cells with electron microscopy demonstrated abnormally small and dense lamellar body with eccentrically distributed electron dense substance.</p><p><b>CONCLUSION</b>Genetic variants within ABCA3 may be the genetic cause of or a contributor to some unexplained refractory NRDS. Identification of ABCA3 genetic variant in NRDS infants is important to establish appropriate management and evaluation of treatment options, as well as to offer genetic counseling and prenatal diagnosis.</p>
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Humans , Infant, Newborn , ATP-Binding Cassette Transporters , Genetics , DNA Mutational Analysis , Exons , Polymorphism, Genetic , Respiratory Distress Syndrome, Newborn , GeneticsABSTRACT
Objective To study the toxic effects of 5-amionlevulinic acid-based photodynamic therapy (ALA-PDT) on human peripheral blood mononuclear cells (PBMCs), cord blood mononuclear cells (CBMCs) and peripheral blood stem cells (PBSCs), and furthermore, to understand the possible causes of this response. Methods We used MTT assay to detect the survival rate of PBMCs, CBMCs and PBSCs after treated by ALA-PDT under the optimum experiment conditions with U937 as control;Annexin V-FITC/PI was used to detect the pattern of cell death induced by ALA-PDT. By using flow cytometry, we detected intracellular PpIX fluorescence intensity. Results After ALA-PDT treatment the survival rate of PBMCs had no significant change;however in PBSCs and CBMCs, the survival rate reduced to 70%, and the survival rate of leukemia cell U937 was the lowest, about 30%. After incubation with ALA,except for PBMCs, intraceUuiar PplX fluorescence intensity of the other two kinds of normal haemocytes and U937 increased obviously. These results combined with the flow cytometry suggested that the main pattern of cell death here was apoptosts. Conclusion Under the optimum experiment conditions, ALA-PDT has a slight effect on normal haemocytes but excellent depletions of leukemia cells. Therefore, it can effectively purify autologons bone marrow or stem cell grafts.
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This experiment was designed to explore the pattern of K562 and HL60 leukemia cells death, the effects on their cell cycle and the cytoplasmic free calcium concentration ([Ca2+]i) induced by 5-aminolaevulinic acid-based photodynamic therapy (ALA-PDT). Under the transmission electron microscope (TEM), two kinds of leukemia cells' ultrastructure were observed. Flow cytometry combined with Annexin V-FITC/PI labeling was used to detect the pattern of K562 and HL60 cells' death induced by ALA-PDT. Flow cytometry combined with PI labeling was used to analyze the change in the cell cycle induced by ALA-PDT, and confocal laser scanning microscopy (CLSM) combining with calcium fluorescence probe was used to detect the change in the cytoplasmic free calcium concentration ([Ca2+]i). Immediately after irradiation, many typical apoptotic bodies were seen in the cells treated. Most of the cells treated were necrotic at 24 hours following irradiation. Flow cytometry analysis suggested that the main patterns of the cells' death were apoptosis immediately after irradiation and necrosis post-apoptosis at 24 hours post irradiation. Immediately and 24 hours after irradiation, the proportion of S phase of K562 was 57. 67% +/- 1.13% and 84.77% +/- 6.20% respectively, and the proportion of S phase of HL60 was 74.60% +/- 7.27% and 84.60% 1.74% respectively. Both [Ca+]i of the treated K562 and HL60 were increased obviously. In the best experiment condition, the initial pattern of the K562 and HL60 leukemia cells' death induced by PDT was apoptosis and the main pattern was necrosis post apoptosis. The two kinds of cells were arrested at S phase by ALA-PDT. During the death of the leukemia cells, the increase in intracellular free calcium concentration could be responsible for the ALA photodynamically induced damage to K562 and HL60 cells.