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Qian Peng

Publications and source records attributed to Qian Peng.

At least 19 recordsLinked to original sources
PubMed2026

Construction of an infectious clone of Spodoptera frugiperda densovirus and its biological characteristics.

Densoviruses are highly pathogenic to their insect hosts and have great potential for biocontrol. Spodoptera frugiperda densovirus (SfDV) was isolated from diseased larvae of Spodoptera frugiperda, while its biological functions remain unclear. Herein, we successfully constructed an infectious clone of SfDV. The S. frugiperda larvae transfected with the infectious clone exhibited anorexia, stunted growth, and reduced activity. Histopathological analysis further showed that the epidermis, fat body and trachea were infected instead of muscle and midgut tissues. Transmission electron microscopy (TEM) revealed that numerous virions of about 22 nm were distributed within both the nucleoplasm and cytoplasm of epidermal cells. Moreover, many virions were also found contained within vesicles in the cytoplasm. The replication kinetics of the rescued SfDV (rSfDV) was similar to that of the parental SfDV. The median lethal dose (LD50) and median lethal time (LT50) values of rSfDV were 6.63 × 107 viral genome copies (vgc), 5.23 d, respectively, which were also comparable to those of the parental SfDV. Taken together, the infectious clone of SfDV provides an important tool for further exploring the genome function, pathogenesis, and interactions with its hosts.

Animals↗
PubMed2026

Genetic Correlation Between Brain Imaging Phenotypes and Externalizing Behavior: A Large-Scale LDSC Analysis of UK Biobank IDPs.

Externalizing has been associated with differences in brain structure and function; however, it remains unclear whether these associations reflect shared common-variant genetic influences. Cross-trait linkage disequilibrium score regression was used to estimate genome-wide genetic correlations between externalizing genome-wide association study (GWAS) results and 3,935 brain imaging-derived phenotypes from the UK Biobank BIG40 resource. The imaging phenotypes covered structural magnetic resonance imaging (MRI), diffusion MRI, susceptibility-weighted imaging, resting-state functional MRI, and task-based functional MRI. Results were included in the primary analysis when the imaging phenotype had positive single-nucleotide polymorphism (SNP) heritability, a heritability Z statistic of at least 1.96, a mean GWAS chi-square statistic of at least 1.02, at least 200,000 regression SNPs, and a complete LDSC result without a fatal error. Technical imaging quality-control phenotypes were excluded from biological inference. Individual results were corrected using the Benjamini-Hochberg false discovery rate procedure. Aggregated Cauchy association tests (ACATs) were used to evaluate evidence across all imaging phenotypes and within predefined imaging categories. Statistical power, simultaneous confidence bounds, and alternative quality-control definitions were examined in sensitivity analyses. Of the 3,935 imaging phenotypes, 3,716 produced estimable genetic correlations, 2,980 met the primary LDSC quality-control criteria, and 2,967 were classified as biological imaging phenotypes. No individual phenotype survived false discovery rate correction. The smallest unadjusted P value was 0.0005, and the minimum adjusted q value was 0.486. The distribution of genetic correlations was centered near zero, with a median genetic correlation of 0.0014 and a median absolute genetic correlation of 0.0338. ACAT provided no evidence of an aggregate association across all biological imaging phenotypes (P = 0.302), and no predefined imaging category survived multiple-testing correction. The median minimum detectable genetic correlation at 80% power was 0.216. Bonferroni-adjusted simultaneous confidence intervals were fully contained within the interval [-0.30, 0.30] for 80.0% of phenotypes in the primary analysis and 88.0% under the stringent heritability quality-control definition. Broad and stringent sensitivity analyses produced the same overall conclusions. In this study, no statistically robust evidence of genome-wide genetic correlations between externalizing and individual UK Biobank brain imaging phenotypes was found. Nevertheless, small, localized, mixed-direction, or developmentally specific genetic effects remain possible.

Journal Article↗
PubMed2026

Evaluation of epistasis detection methods for quantitative phenotypes.

MOTIVATION: Epistasis, or genetic interaction, plays a crucial role in shaping complex traits and has been increasingly recognized for its widespread influence in genetic architectures. While epistasis detection has been extensively evaluated in case-control studies, its performance with quantitative phenotypes remains comparatively understudied. RESULTS: We identified and evaluated six epistasis detection methods applicable to quantitative trait analysis: EpiSNP, Matrix Epistasis, MIDESP, PLINK Epistasis, QMDR, and REMMA. Using the EpiGEN simulator, we generated synthetic datasets modeling four classes of pairwise SNP interactions-dominant, multiplicative, recessive, and XOR. We also assessed BOOST and MDR algorithms using discretized (case-control) versions of the same datasets. Performance varied notably by interaction type: REMMA achieved the highest overall detection rate (55%), particularly excelling with dominant interactions (100%). MDR excelled with multiplicative (57%) and XOR (69%) interactions. Meanwhile, EpiSNP attained the best performance for recessive interactions (67%). All methods except BOOST produced F1 scores below 0.05 for most interaction types. We further evaluated the methods using a real-world dataset. When applied to the Adolescent Brain Cognitive Development dataset to analyse the externalizing behavior phenotype, both PLINK Epistasis and PLINK BOOST identified SNPs within the DRD2 and DRD4 genes, consistent with previously reported genetic associations. Given the variability in tool performance across interaction types, no single method provides optimal detection across all scenarios. Leveraging multiple detection algorithms may therefore yield more comprehensive insights into epistatic effects in quantitative trait analyses. AVAILABILITY AND IMPLEMENTATION: All relevant code and simulated datasets can be found at github.com/staslist/Epistasis_Review repository.

Epistasis, Genetic↗
PubMed2026

Multi-Ancestry Survival GWAS of Substance Use Initiation in the ABCD Study.

BACKGROUND: Substance use initiation in adolescence is influenced by both genetic and environmental factors; however, large-scale genetic studies often treat initiation as a binary outcome and underuse longitudinal timing information. METHODS: We conducted time-to-event (survival) genome-wide association analyses (GWAS) of initiation for four outcomes-alcohol, nicotine, cannabis, and any substance use-using longitudinal follow-up data from the Adolescent Brain Cognitive Development (ABCD) Study. We performed ancestry-stratified GWAS within European (EUR), African (AFR), and Hispanic (HISP) groups, applying consistent quality control and covariate adjustment. Summary statistics were harmonized across ancestries and meta-analyzed using inverse-variance weighted fixed-effects and DerSimonian-Laird random-effects models. We evaluated genomic inflation and heterogeneity (Cochran's Q and I 2), identified independent lead variants at genome-wide and suggestive significance thresholds, and assessed cross-trait overlap of associated loci. RESULTS: In the multi-ancestry meta-analysis, we observed suggestive association signals across traits (minimum p-values: alcohol ~ 1 &#xd7; 10-7, any ~ 1 &#xd7; 10-7, cannabis ~ 5 &#xd7; 10-8, nicotine ~ 1 &#xd7; 10-8). Nicotine initiation showed one genome-wide significant variant in both fixed- and random-effects meta-analyses (p < 5 &#xd7; 10-8). Across traits, suggestive loci demonstrated limited overlap, with the strongest concordance between alcohol and any substance use, consistent with shared liability. Heterogeneity statistics indicated that some loci exhibited cross-ancestry variation in effect estimates. CONCLUSIONS: Survival GWAS leveraging initiation timing can identify genetic signals that may be missed by binary designs and enables principled multi-ancestry synthesis. Our results highlight both shared and trait-specific genetic contributions to early substance initiation and provide a foundation for downstream functional annotation and integrative modeling with environmental risk factors. These findings demonstrate the value of incorporating developmental timing into genetic discovery and provide a framework for integrating longitudinal risk modeling with genomic analyses.

ABCD↗
PubMed2006

Ex vivo and in vivo delivery of anti-tissue factor short interfering RNA inhibits mouse pulmonary metastasis of B16 melanoma cells.

PURPOSE: The coagulation trigger tissue factor has been implicated in tumor growth, angiogenesis, and metastasis. In this study, we explore the effects of ex vivo and in vivo delivery of short interfering RNA (siRNA) targeting tissue factor on B16 melanoma colonization of the lung in a murine model for metastasis. The purposes of this work are to establish a noncytotoxic in vivo model for investigation of tissue factor function and provide preclinical assessment of the therapeutic potential of tissue factor siRNA for prevention of metastasis. EXPERIMENTAL DESIGN AND RESULTS: C57BL/6 mice were evaluated for pulmonary metastases following tail vein injection of B16 cells transfected with either active or inactive siRNA. Mice receiving cells transfected with active siRNA had significantly lower numbers of pulmonary tumors compared with mice injected with control cells (transfected with inactive siRNA). The average time point at which the mice started to exhibit tumor-associated stress was also increased significantly from 22 days for the control group to 27 days for the experimental group (P = 0.01). In a therapeutically more relevant model, where the siRNA was delivered i.p. and the cells (untransfected) by tail vein injection, an inhibitory effect on metastasis was observed when the siRNA treatment was initiated either before or at the time of cell injection. CONCLUSIONS: The results suggest that tissue factor has a crucial function in promoting lung tumor metastasis of blood-borne tumor cells in the early stages of the tumor take process and further suggest that treatment with tissue factor siRNA may become a viable clinical strategy for prevention of tumor metastasis.

Animals↗
PubMed2006

Subcellular localization pattern of protoporphyrin IX is an important determinant for its photodynamic efficiency of human carcinoma and normal cell lines.

Photodynamic therapy (PDT) is a combination of light with a lesion-localizing photosensitizer or its precursor to destroy the lesion tissue. PDT has recently become an established modality for several malignant and non-malignant conditions, but it can be further improved through a better understanding of the determinants affecting its therapeutic efficiency. In the present investigation, protoporphyrin IX (PpIX), an efficient photosensitizer either endogenously induced by 5-aminolevulinic acid (ALA) or exogenously administered, was used to correlate its subcellular localization pattern with photodynamic efficiency of human oesophageal carcinoma (KYSE-450, KYSE-70) and normal (Het-1A) cell lines. By means of fluorescence microscopy ALA-induced PpIX was initially localized in the mitochondria, whereas exogenous PpIX was mainly distributed in cell membranes. At a similar amount of cellular PpIX PDT with ALA was significantly more efficient than photodynamic treatment with exogenous PpIX at killing all the 3 cell lines. Measurements of mitochondrial membrane potential and intracellular ATP content, and electron microscopy showed that the mitochondria were initially targeted by ALA-PDT, consistent with intracellular localization pattern of ALA-induced endogenous PpIX. This indicates that subcellular localization pattern of PpIX is an important determinant for its PDT efficiency in the 3 cell lines. Our finding suggests that future new photosensitizers with mitochondrially localizing properties may be designed for effective PDT.

Adenosine Triphosphate↗
PubMed2006

The fragile breakage versus random breakage models of chromosome evolution.

For many years, studies of chromosome evolution were dominated by the random breakage theory, which implies that there are no rearrangement hot spots in the human genome. In 2003, Pevzner and Tesler argued against the random breakage model and proposed an alternative "fragile breakage" model of chromosome evolution. In 2004, Sankoff and Trinh argued against the fragile breakage model and raised doubts that Pevzner and Tesler provided any evidence of rearrangement hot spots. We investigate whether Sankoff and Trinh indeed revealed a flaw in the arguments of Pevzner and Tesler. We show that Sankoff and Trinh's synteny block identification algorithm makes erroneous identifications even in small toy examples and that their parameters do not reflect the realities of the comparative genomic architecture of human and mouse. We further argue that if Sankoff and Trinh had fixed these problems, their arguments in support of the random breakage model would disappear. Finally, we study the link between rearrangements and regulatory regions and argue that long regulatory regions and inhomogeneity of gene distribution in mammalian genomes may be responsible for the breakpoint reuse phenomenon.

Algorithms↗
PubMed2006

Induction of hypoxia-inducible factor-1alpha overexpression by cobalt chloride enhances cellular resistance to photodynamic therapy.

Although photodynamic therapy (PDT) has been approved by regulatory agencies worldwide for the treatment of several oncologic and non-oncologic conditions, PDT-induced tissue hypoxia as a result of vascular damage and photochemical oxygen consumption limits the efficacy of this modality. This may largely be due to hypoxia-mediated angiogenesis via hypoxia-inducible factor-1alpha (HIF-1alpha), a major transcription factor involved in angiogenesis, hematopoiesis and anaerobic energy metabolism. We hypothesized that hypoxia-induced HIF-1alpha overexpression may also lead to tumor cells resistant to PDT by favouring tumor cell proliferation. Human esophageal normal Het-1A and tumor KYSE-70 and KYSE-450 cell lines were used in the present study. High-expression of HIF-1alpha induced in vitro by cobalt chloride (CoCl(2))-mediated chemical hypoxia mimic was clearly seen in the Het-1A cell line. In addition, cells treated with CoCl(2) were more resistant to 5-aminolevulinic acid (ALA)-mediated PDT than those without CoCl(2) treatment. The photosensitivity of the cells to ALA-PDT decreased with increasing HIF-1alpha expression by enhancing CoCl(2) concentrations. Moreover, transfection of the cells with anti-HIF-1alpha short interfering RNA (siRNA) knocked down the HIF-1alpha expression and restored the photosensitivity of the cells to ALA-PDT. However, the induction of HIF-1alpha expression by CoCl(2) was not indicated in both KYSE-70 and KYSE-450 cell lines, and no difference in cell survival was found after ALA-PDT in the presence and absence of CoCl(2). We thus conclude that high-expression of HIF-1alpha induced by CoCl(2) plays an important role in the resistance of the Het-1A cells to ALA-PDT. The present finding suggests that hypoxia-induced HIF-1alpha overexpression attenuates PDT efficacy through probably not only angiogenesis, but also cellular resistance to the modality. PDT in combination with anti-HIF-1alpha treatment may thus enhance the PDT efficacy.

Aminolevulinic Acid↗
PubMed2006

Involvement of both caspase-dependent and -independent pathways in apoptotic induction by hexaminolevulinate-mediated photodynamic therapy in human lymphoma cells.

Photodynamic therapy (PDT) is a cancer treatment based on the interaction of a photosensitizer, light and oxygen. PDT with the endogenous photosensitizer, protoporphyrin IX (PpIX) induced by 5-aminolevulinic acid (ALA) or its derivatives is a modification of this treatment modality with successful application in dermatology. However, the mechanism of cell destruction by ALA-PDT has not been elucidated. In this study a human T-cell lymphoma Jurkat cell line was treated with PDT using hexaminolevulinate (HAL, hexylester of ALA). Four hours following treatment nearly 80% of the cells exhibited typical apoptotic features. Mitochondrial pro-apoptotic proteins were evaluated by Western blots in subcellular fractionated samples. PDT caused cytosolic translocation of cytochrome c and nuclear redistribution of apoptosis-inducing factor (AIF), but the release of mitochondrial Smac/DIABLO, Omi/HtrA2 and EndoG was not observed. The release of cytochrome c was followed by the cleavage of caspase-9 and caspase-3 as well as its downstream substrates, together with oligonucleosomal DNA fragmentation. The pan-caspases inhibitor, z-VAD.fmk, prevented oligonucleosomal DNA fragmentation, but failed to inhibit PDT-mediated apoptosis. The apoptotic induction by AIF-mediated caspase-independent pathway was also found after HAL-PDT with large-scale DNA fragmentation in the presence of z-VAD.fmk. These results demonstrate that cytochrome c-mediated caspase-dependent pathway and AIF-induced caspase-independent pathway are simultaneously involved in the apoptotic induction by PDT. When the cytochrome c-induced caspase-dependent pathway is blocked, the cells go into apoptosis via AIF-mediated pathway, clearly demonstrating that the cytochrome c-mediated caspase-dependent pathway is not required for such apoptotic induction. This finding may have an impact on improved PDT effectiveness.

Amino Acid Chloromethyl Ketones↗
PubMed2006

Porphyrin formation in actinic keratosis and basal cell carcinoma after topical application of methyl 5-aminolevulinate.

Photodynamic therapy using topical methyl 5-aminolevulinate (MAL) is a new treatment modality for basal cell carcinoma (BCC) and actinic keratosis (AK). MAL induces endogenous porphyrins, which act as photosensitizers. Pharmacokinetic studies of the porphyrin-inducing effect of MAL creams (Metvix) applied in different concentrations (16-160 mg/g) and application times are presented. Surface fluorescence measurements were used to monitor porphyrin accumulation in 18 superficial BCCs and 32 AKs. For both lesion types, the fluorescence increased during the first 13 of 28 hours of continuous MAL application. A 20-fold site-to-site variation was observed, and there were no significant MAL concentration dependencies. The selectivity between lesions and normal skin was 10-fold during the first hours and decreased throughout the application time. Fluorescence microscopy images of tissue sections from 32 nodular BCCs were analyzed to calculate the porphyrin content in tumor tissue as a function of depth. Significant correlation to MAL concentration was seen within the tumors treated for 3 hours. Increase to 18-hour MAL application enhanced the fluorescence levels in superficial tumor layers, but not in deep layers. In conclusion, application of the 160 mg/g cream for 3 hours gave advantageous porphyrin distributions for all types of lesions.

Administration, Topical↗
PubMed2006

Comparison of merocyanine 540-mediated photodynamic action on leukemia cells between pulsed and continuous wave light sources.

Whether a pulsed laser is superior to a continuous wave (CW) light source in photodynamic therapy (PDT) of cancer is still unclear and contradictory in the literature. Although photosaturation of a sensitizer and oxygen depletion in tumor have been considered to be involved during pulsed laser irradiation, there is a lack of experimental data. In the present work several parameters such as the amount of merocyanine 540 (MC540) in cells, the oxygen concentration in cells, and the amount of photos reaching cells during pulsed laser irradiation, were studied to compare the MC540-mediated PDT effects of a pulsed laser and a CW light source on murine myeloid WEH-3B (JCS) cells in vitro. The results showed that the pulsed laser was less effective at cell inactivation than the CW light under the same irradiation dose. However, when the energy of the pulsed laser was reduced from 0.25 to 0.06 mJ/cm2 while keeping the total irradiation dose unchanged, the photoinactivation of cells was increased significantly. Based on the measurements and calculations for the present experimental conditions, each cell has about 108 MC540 molecules bound (5 microg/ml MC540 for 1 hr) and receives about 109 photos from 0.25 mJ/cm2 of the pulsed laser. The results indicate that the photosaturation of MC540 occurs in the present conditions due to the fact that the photons received by one cell in one laser pulse were much more than the numbers of MC540 molecules bound to one cell. Thus, the photosaturation of the photosensitizer is one of the reasons to explain the different efficiency in cell inactivation between the pulsed laser and CW light.

Animals↗
PubMed2006

Repetitive photodynamic therapy of malignant brain tumors.

The probability of achieving local control with current single-shot, intraoperative photodynamic therapy (PDT) treatments of intracerebral gliomas seems improbable due to the length of time required to deliver adequate light fluences to depths of 1-2 cm in the resection margin. Additionally, due to the short doubling time of many malignant gliomas, the kill rate per cell doubling indicates that it seems unlikely that a single treatment would be sufficient to prevent tumor recurrence. Multiple repetitive treatments would therefore seem required. In this publication we primarily review our work examining the effects of repetitive PDT on malignant brain tumor cells both in vitro and in vivo. The in vitro therapy response of human and rat glioma spheroids to 5-aminolevulinic acid (ALA)-mediated PDT in repetitive form was investigated. The results indicated that PDT repeated at relatively long intervals (weeks) was more effective at inhibiting spheroid growth than either daily fractionated PDT or single-treatment regimes. The in vivo response to repetitive treatment was evaluated in a rodent glioma model where BT4C cell line tumors were established in the brains of inbred BD-IX rats. Microfluorometry of frozen tissue sections showed that PpIX is produced with a 10-20:1 tumor to normal tissue selectivity ratio 4 hr after ALA injection. Preliminary evidence of increased efficacy of repetitive PDT and low fluence rate treatment is presented.

Aminolevulinic Acid↗
PubMed2006

New derivatives of 5-aminolevulinic acid for photodynamic therapy: chemical synthesis and porphyrin production in in vitro and in vivo biological systems.

Photodynamic therapy (PDT) has become a new treatment for several oncological and nononcological disorders. This procedure involves systemic or topical administration of a lesion-localizing photosensitizer or prodrug, followed by irradiation with visible light to cause singlet oxygen-induced damage to the target tissue. 5-aminolevulinic acid (ALA) is an endogenous precursor for several photosensitizing porphyrins formed by heme biosynthesis, and has been studied for PDT with promising results for some superficial diseases of the skin and hollow internal organs. Hydrophilic ALA has a limited ability to penetrate certain biological barriers and has a relatively low selectivity for lesions. In addition, its ability to induce intracellular porphyrins has been shown to be low compared to most esters of ALA. This stimulated a search for lipophilic derivatives of ALA to overcome the shortcomings of ALA. Thirty-two new esters of ALA were prepared and their ability to induce porphyrin formation was assessed in the WiDr human carcinoma cell line in vitro and in the normal skin of Balb/c nude mice in vivo. Branched-chain alkyl esters and substituted benzyl esters were found to be the most efficient porphyrin precursors of the compounds studied.

Aminolevulinic Acid↗
PubMed2006

Induction of apoptosis by hexaminolevulinate-mediated photodynamic therapy in human colon carcinoma cell line 320DM.

Photodynamic therapy (PDT) typically involves systemic or topical administration of a tumor-localizing photosensitizer or prodrug and its subsequent activation by visible light. This results primarily in singlet oxygen-induced photodamage to the tumor. 5-Aminolevulinic acid (ALA) and its derivatives have recently been widely used for PDT due to their selective induction in tumor of endogenous protoporphyrin IX (PpIX), a potent photosensitizer. Although ALA-PDT has achieved successful results in the treatment of several clinical oncological and nononcological diseases, the mechanisms of this modality are still not fully elucidated. In the present study, the human colon carcinoma cell line 320DM was treated in vitro with PDT using hexaminolevulinate (HAL), a hexylester of ALA known to be 50 to 100 times more efficient at producing PpIX formation than ALA itself. PpIX production increased with increasing HAL concentrations in the cells and phototoxicity of the cells was enhanced with increasing light (450 nm) doses. HAL-PDT induced apoptotic cell death, as measured by nuclear staining of Hoechst 33342 for fluorescence microscopy, DNA electrophoresis and TdT staining for flow cytometry. PDT with 5 muM of HAL and a light dose of 640 mJ/cm2 produced a 75% apoptotic cell population 40 hr after the treatment. Furthermore, the loss of mitochondrial membrane potential coincident with the release of cytochrome c from the mitochondria into the cytosol led to a rapid activation of caspase-9 and caspase-3 (an executioner), indicating that the selective damage to the mitochondria by HAL-PDT can induce a cytochrome-c-mediated apoptotic response in the 320DM cells.

Aminolevulinic Acid↗
PubMed2006

Influence of light fluence rate on the effects of photodynamic therapy in an orthotopic rat glioma model.

OBJECT: Failure of treatment for high-grade gliomas is usually due to local recurrence at the site of resection, indicating that a more aggressive local therapy could be beneficial. Photodynamic therapy (PDT) is a local treatment involving the administration of a tumor-localizing photosensitizing drug, in this case aminolevulinic acid (ALA). The effect depends on the total light energy delivered to the target tissue, but may also be influenced by the rate of light delivery. METHODS: In vitro experiments showed that the sensitivity to ALA PDT of BT4C multicellular tumor spheroids depended on the rate of light delivery (fluence rate). The BT4C tumors were established intracranially in BD-IX rats. Microfluorometry of frozen tissue sections showed that photosensitization is produced with better than 200:1 tumor/normal tissue selectivity after ALA injection. Four hours after intraperitoneal ALA injection (125 mg/kg), 26 J of 632 nm light was delivered interstitially over 15 (high fluence rate) or 90 (low fluence rate) minutes. Histological examination of animals treated 14 days after tumor induction demonstrated extensive tumor necrosis after low-fluence-rate PDT, but hardly any necrosis after high-fluence-rate treatment. Neutrophil infiltration in tumor tissue was increased by PDT, but was similar for both treatment regimens. Low-fluence-rate PDT administered 9 days after tumor induction resulted in statistically significant prolongation of survival for treated rats compared with nontreated control animals. CONCLUSIONS: Treatment with ALA PDT induced pronounced necrosis in tumors only if the light was delivered at a low rate. The treatment prolonged the survival for tumor-bearing animals.

Aminolevulinic Acid↗
PubMed2006

[Clinical study on improving the diagnostic criteria for neonatal asphyxia].

OBJECTIVE: Diagnosing neonatal asphyxia solely according to Apgar score may lead to misdiagnosis. The aim of this study was to explore new and more accurate diagnostic criteria for neonatal asphyxia. METHODS: Totally 10 376 live born neonates in our hospital were consecutively enrolled into the study. The following five items related to birth asphyxia, i.e., antepartum high-risk factors, Apgar scores, umbilical artery blood pH, organ injury, differential diagnosis on the causes of low Apgar score cases were examined and registered. The relationship among the first 4 items were analyzed. By differential diagnosis, the sensitivity and specificity of each index on diagnosing asphyxia and their complementary value on each other were investigated. RESULTS: The items correlated well with each other (P < 0.01 or < 0.05) but were not entirely parallel and consistent; they could complement but could not substitute for each other. The sensitivity of antepartum high-risk factors, low Apgar scores, umbilical artery blood pH < 7.00 and organ injury was 100%, 100%, 44.44% and 100%, while the specificity was 17.99%, 98.90%, 96.05% and 96.62%, respectively. Of the 230 low Apgar score cases in this series only 50.9% coincided with asphyxia. For the 230 cases, when low Apgar score was combined with umbilical artery blood pH < 7.00, the sensitivity and specificity were 41% and 99.1% and when low Apgar score was combined with umbilical artery blood pH < 7.20, the sensitivity and specificity were 100% and 29.20%, respectively. After organ injury was added, the specificity was increased to 65.49%. When differential diagnosis was further added to exclude the other causes of low Apgar score cases, the misdiagnosis rate was minimized. CONCLUSION: Up to now, no single accurate index for diagnosing neonatal asphyxia is available. In order to increase diagnostic bases and reduce misdiagnosis, the criteria of sole Apgar score should be replaced by multi-index diagnostic criteria. Based on the present study, a set of integrated diagnostic criteria for neonatal asphyxia is proposed: (1) prenatal high-risk factors, (2) low Apgar scores (respiratory depression must present), (3) umbilical artery blood pH < 7.00, if only pH < 7.20, the items (2) (4) (5) must be present, (4) hypoxic-ischemic organ injury (at least one organ dysfunction), (5) the other causes of low Apgar scores should be excluded. The last 4 indexes should all be met and the first one serves as reference. If multi-organ (three or more organs) dysfunction and (or) hypoxic-ischemic encephalopathy are present, severe asphyxia can be diagnosed.

Apgar Score↗