SiamFDA: feature dynamic activation siamese network for visual tracking

In this paper, we present a novel anchor-free visual tracking framework, referred to as feature dynamic activation siamese network (SiamFDA), which addresses the issue of ignoring global spatial information in current Siamese network-based tracking algorithms. Our approach captures long-range dependencies between distant pixels in space, which enables robustness to unreliable regions. Additionally, we introduce a hierarchical feature selector that adaptively activates features at different layers, and an adaptive sample label assignment method to further improve tracking performance. Our extensive evaluations on six benchmark datasets, including VOT-2018, VOT-2019, GOT10k, LaSOT, OTB-2015, and OTB-2013, demonstrate that SiamFDA outperforms several state-of-the-art trackers in various challenging scenarios, with a real-time frame rate of 40 frames per second.

Systematic analysis of prophages carried by Porphyromonas gingivalis

To systematically investigate the prophages carrying in Porphyromonas gingivalis (P. gingivalis) strains, analyze potential antibiotic resistance genes (ARGs) and virulence genes in these prophages. We collected 90 whole genome sequences of P. gingivalis from NCBI and utilized the Prophage Hunter online software to predict prophages; Comprehensive antibiotic research database (CARD) and virulence factors database (VFDB) were adopted to analyze the ARGs and virulence factors (VFs) carried by the prophages. Sixty-nine prophages were identified among 24/90 P. gingivalis strains, including 17 active prophages (18.9%) and 52 ambiguous prophages (57.8%). The proportion of prophages carried by each P. gingivalis genome ranged from 0.5% to 6.7%. A total of 188 antibiotic resistance genes belonging to 25 phenotypes and 46 different families with six mechanisms of antibiotic resistance were identified in the 17 active prophages. Three active prophages encoded 4 virulence genes belonging to type III and type VI secretion systems. The potential hosts of these virulence genes included Escherichia coli, Shigella sonnei, Salmonella typhi, and Klebsiella pneumoniae. In conclusion, 26.7% P. gingivalis strains carry prophages, while the proportion of prophage genes in the P. gingivalis genome is relatively low. In addition, approximately 39.7% of the P. gingivalis prophage genes have ARGs identified, mainly against streptogramin, peptides, and aminoglycosides. Only a few prophages carry virulence genes. Prophages may play an important role in the acquisition, dissemination of antibiotic resistance genes, and pathogenicity evolution in P. gingivalis.

A biopsychosocial-cultural model for understanding oral-health-related quality of life among adolescent orthodontic patients

Background

Based on previous theoretical oral-health-related quality of life (OHRQoL) models and most recently framework, as well as sociocultural model of body image dissatisfaction, the current study aimed to investigate the effect of individual (dental aesthetics and dental appearance social comparison) and sociocultural factors (social reinforcement from parents, peers and mass media on dental aesthetics) as well as their interaction on psychosocial dimension of OHRQoL among adolescent orthodontic patients.

Methods

In this cross-sectional study comprising 427 adolescent orthodontic patients (151 boys and 276 girls) aged between 11 and 16 years old, the psychosocial dimension of OHRQoL was measured by Psychosocial Impact of Dental Aesthetics Questionnaire. Individual predictor of dental aesthetics was defined by the Aesthetic Component of the Index of Orthodontic Treatment Need, and dental appearance social comparison was assessed by four items adapted from Physical Appearance Comparison Scale. Sociocultural predictor of social reinforcement was measured by six items adapted from Perceived Sociocultural Pressure Scale. Spearman correlations, path analyses, and structural equation modeling were used to build up several predictive models.

Results

As hypothesized, two direct pathways were observed that patients’ dental aesthetics and all three sources of social reinforcement directly predicted the psychosocial dimension of OHRQoL. Meanwhile, we observed one indirect pathway, that three sources of social reinforcement predicted the psychosocial dimension of OHRQoL, in part, through dental appearance social comparison.

Conclusions

This study provides preliminary evidence indicating that dental aesthetics, social reinforcement and dental appearance comparison are reliable predictors of psychosocial dimension of OHRQoL among adolescent orthodontic patients.

Robust reduced-rank regression

In high-dimensional multivariate regression problems, enforcing low rank in the coefficient matrix offers effective dimension reduction, which greatly facilitates parameter estimation and model interpretation. However, commonly used reduced-rank methods are sensitive to data corruption, as the low-rank dependence structure between response variables and predictors is easily distorted by outliers. We propose a robust reduced-rank regression approach for joint modelling and outlier detection. The problem is formulated as a regularized multivariate regression with a sparse mean-shift parameterization, which generalizes and unifies some popular robust multivariate methods. An efficient thresholding-based iterative procedure is developed for optimization. We show that the algorithm is guaranteed to converge and that the coordinatewise minimum point produced is statistically accurate under regularity conditions. Our theoretical investigations focus on non-asymptotic robust analysis, demonstrating that joint rank reduction and outlier detection leads to improved prediction accuracy. In particular, we show that redescending ψ-functions can essentially attain the minimax optimal error rate, and in some less challenging problems convex regularization guarantees the same low error rate. The performance of the proposed method is examined through simulation studies and real-data examples.

Effects of graded levels of microbial phytase on apparent total tract digestibility of calcium and phosphorus and standardized total tract digestibility of phosphorus in four sources of canola meal and in soybean meal fed to growing pigs

One hundred twenty pigs were used to determine effects of graded levels of microbial phytase on the apparent total tract digestibility (ATTD) of P and Ca and the standardized total tract digestibility (STTD) of P in 4 sources of canola meal and in 1 source of soybean meal (SBM) fed to growing pigs. The 4 sources of canola meal were produced from 1 source of high-protein canola seeds and 2 sources of conventional canola seeds with 1 of the conventional canola seeds being divided into 2 separate batches before crushing. Pigs (16.2 ± 5.3 kg initial BW) were individually housed in metabolism crates and were randomly allotted to 1 of 20 diets in a 5 × 4 factorial arrangement of treatments with 5 ingredients and 4 levels of phytase. There were 6 replicate pigs per diet. Five basal diets based on high-protein canola meal (CM-HP), high-temperature processed canola meal (CM-HT), low-temperature processed canola meal (CM-LT), conventional canola meal (CM-CV), or SBM were formulated. The basal diets contained no phytase. Fifteen additional diets were prepared by adding approximately 500, 1,500, or 2,500 phytase units/kg to each of the 5 basal diets. Feces were quantitatively collected for 5 d based on the marker-to-marker approach after a 7-d adaptation period. Results indicated that supplementation of microbial phytase increased (linear, < 0.05) the ATTD of Ca in diets containing CM-HP, CM-HT, CM-CV, and SBM but not in diets containing CM-LT. Microbial phytase also increased (linear and quadratic, < 0.05) the ATTD and STTD of P in all 5 ingredients. Compared with the CM-CV diets, the CM-HP diets had greater ( < 0.05) ATTD of Ca. The ATTD of Ca in the SBM diet was greater ( < 0.05) than in all canola meal diets, but no differences were observed in ATTD of Ca between CM-HT and CM-LT diets. The ATTD and the STTD of P were less ( < 0.05) in CM-HP, CM-HT, CM-LT, or CM-CV than in SBM if no microbial phytase was added, but no differences were observed in the ATTD and STTD of P in SBM, CM-HP, CM-HT, or CM-CV if the highest amount of phytase were added (interaction, < 0.05). Regression equations were developed to calculate the response to microbial phytase on the STTD of P in CM-HP, CM-HT, CM-LT, CM-CV, and SBM. In conclusion, inclusion of graded levels of microbial phytase increased the ATTD and STTD of P in CM-HP, CM-HT, CM-LT, CM-CV, and SBM and the response to microbial phytase added to each ingredient can be predicted by regression equations.

Ghrelin to obestatin ratio in maternal serum in pregnancies complicated by intrauterine growth restriction

Ghrelin, an endogenous for the growth hormone secretagogue receptor, has been shown to participate in fetal growth. Obestatin, encoded by the same gene as ghrelin, is described as a physiological opponent of ghrelin. This study was designed to determine the changes of ghrelin/obestatin ratio in maternal serum in pregnancies with intrauterine growth restriction (IUGR). The authors found that the ghrelin levels in maternal serum were significent lower in IUGR group than in control group (236.34 ± 14.58 pg/ml vs. 321.49 ± 18.19 pg/ml, p = 0.003). However, the difference of obestatin levels in maternal serum in IUGR group than in control group was not significent (276.25, ±20.54 pg/ml vs. 256.34 ± 21.21 pg/ml, p = 0.308). The ratio of ghrelin to obestatin in maternal serum were significent lower in UGR group than in control group (1.05 ± 0.09 vs. 0.82 ± 0.08, p = 0.03). Meanwhile, the maternal serum growth hormone (GH) concentration in IUGR group was lower than that in control group (1.08 ± 0.08 pg/ml vs. 1.41 ± 0.09 pg/ml, p = 0.009), and the maternal serum pla- cental growth hormone (PGH) concentration in IUGR group was lower than that in control group (2.21 ± 1.24 pg/ml vs. 2.92 ± 0.27 pg/ml,p = 0.031). The ratio of ghrelin to obestatin in maternal serum were positively correlation with GH and PGH concentrations in IUGR group (r = 0.876, p = 0.52; r = 0.764, p = 0.64). The findings of this study suggest that the ratio of ghrelin to obestatin in maternal serum were low, and were positively correlated with GH and PGH concentration in IUGR group, which can been considered as evidencees of ghrelin/obestatin balance disorder role in pathogenesis of IUGR.

[Effects of anti-PD-L1 monoclonal antibody and EGFR-TKI on the expression of PD-L1 and function of T lymphocytes in EGFR-mutated lung cancer cells]

Objective: To investigate the effects of anti-PD-L1 monoclonal antibody and EGFR-TKI on expression of soluble PD-L1 and function of T lymphocytes in EGFR-mutated lung cancer cells. Methods: Flow cytometry was used to analyze the expression of membrane PD-LI. ELISA was performed to detect the level of sPD-L1 in the supernatant of cultured EGFR-mutated and wild type lung cancer cells before and after erlotinib treatment.After treated with anti-PD-L1 monoclonal antibody alone and in combination with erlotinib, the proliferation of T lymphocytes in co-culture system was measured using Cell Counting Kit-8 (CCK-8) assay. The expression levels of PD-LI and IFN-γ in tumor cells and T lymphocytes treated with erlotinib in co-culture system were analyzed by flow cytometry and ELISA, respectively. Results: PD-L1 was highly expressed in EGFR-mutated lung cancer PC9 cells (78.7±3.1)% and HCC827 cells (82.7±2.6)%.After treated with erlotinib, the expression rates of membrane PD-L1 in PC9 and HCC827 cells were down-regulated (64.7%±3.1% and 73.0%±2.6%, respectively), significantly lower than that in the two cell lines without erlotinib treatment (P<0.05), and the expression levels of sPD-L1 in the supernatant of PC9 and HCC827 cells were also down-regulated (0.680±0.120)ng/ml and (0.903±0.047)ng/ml, respectively, significantly lower than that in the two cell lines without erlotinib treatment (P<0.01). However, no significant changes of membrane PD-L1 and sPD-L1 expression were found in EGFR wild type lung cancer cells (H1299 and A549) before and after erlotinib treatment. In the co-culture system composed of T cells and EGFR-mutated lung cancer cells, treatment with erlotinib alone promoted the proliferation of T lymphocytes (P<0.05), and combined treatment of anti-PD-L1 monoclonal antibody with erlotinib had a stronger effect (P<0.05). In the co-culture system composed of T cells and EGFR wild type cell lines, the proliferation of T cells was not changed after using erlotinib alone or combination of erlotinib and anti-PD-L1 monoclonal antibody (P>0.05). Before and after treatment with erlotinib, the secretion levels of IFN-γ were (856.0±70.3)pg/ml and (1 697.3±161.0)pg/ml, respectively, showing a significant difference (P<0.001). The expression rates of membrane PD-L1 were (76.2±0.5)% and (50.9±0.9)%, respectively, also showing a significant difference (P<0.001). However, no significant changes in the expression of IFN-γ and membrane PD-L1 were found in the co-culture system composed of T cells and A549 cells. Conclusions: Anti-PD-L1 monoclonal antibody combined with EGFR-TKI can effectively promote the proliferation and secretion function of T lymphocytes in the microenvironment of EGFR-mutated lung cancer cells.

My Body Looks Like That Girl's: Body Mass Index Modulates Brain Activity during Body Image Self-Reflection among Young Women

Body image distress or body dissatisfaction is one of the most common consequences of obesity and overweight. We investigated the neural bases of body image processing in overweight and average weight young women to understand whether brain regions that were previously found to be involved in processing self-reflective, perspective and affective components of body image would show different activation between two groups. Thirteen overweight (O-W group, age = 20.31±1.70 years) and thirteen average weight (A-W group, age = 20.15±1.62 years) young women underwent functional magnetic resonance imaging while performing a body image self-reflection task. Among both groups, whole-brain analysis revealed activations of a brain network related to perceptive and affective components of body image processing. ROI analysis showed a main effect of group in ACC as well as a group by condition interaction within bilateral EBA, bilateral FBA, right IPL, bilateral DLPFC, left amygdala and left MPFC. For the A-W group, simple effect analysis revealed stronger activations in Thin-Control compared to Fat-Control condition within regions related to perceptive (including bilateral EBA, bilateral FBA, right IPL) and affective components of body image processing (including bilateral DLPFC, left amygdala), as well as self-reference (left MPFC). The O-W group only showed stronger activations in Fat-Control than in Thin-Control condition within regions related to the perceptive component of body image processing (including left EBA and left FBA). Path analysis showed that in the Fat-Thin contrast, body dissatisfaction completely mediated the group difference in brain response in left amygdala across the whole sample. Our data are the first to demonstrate differences in brain response to body pictures between average weight and overweight young females involved in a body image self-reflection task. These results provide insights for understanding the vulnerability to body image distress among overweight or obese young females.

The complete mitochondrial genome of Teratoscincus roborowskii (Squamata: Gekkonidae)

The complete nucleotide sequence of the mitochondrial genome of Teratoscincus roborowskii was sequenced here. It was determined to be 16,644 base pairs in length and contained 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes and a control region. The 22 tRNA genes could be folded into the typical cloverleaf structure described for vertebrate mitochondrial tRNAs. The base composition of the heavy strand was 30.33% A, 30.35% C, 14.65% G and 24.67% T. The control region was located between the tRNA-Pro and tRNA-Phe genes and is 1248 bp in length and some tandem repeat sequences were found in it.

Attitudes toward HIV pre-exposure prophylaxis among men who have sex with men in western China

Pre-exposure prophylaxis (PrEP), as demonstrated in recently published clinical trials, is one promising approach for controlling the emerging epidemic among men who have sex with men (MSM). We evaluated the attitudes towards use of PrEP among MSM in western China. A total of 1402 participants completed a self-administered questionnaire. Overall, 22% of the participants reported that they had heard of PrEP, <1% had ever used medicine to prevent HIV, and 64% reported that they were absolutely willing to use PrEP if it were proven to be safe and effective. The predictors of willingness to use PrEP included lower education, moderate income compared with the lowest income, never or rarely finding sexual partners through the Internet in the past 6 months, sexually transmitted infection (STI) history, more knowledge of AIDS, worrying about HIV as a threat to themselves and their family, having previously heard of PrEP, and believing that PrEP was effective in preventing HIV. This study demonstrates that Chinese MSM have moderate awareness of PrEP and a high interest in using it.

Complete mitochondrial genome of the Manis pentadactyla (Pholidota, Manidae): comparison of M. pentadactyla and M. tetradactyla

In this paper, we sequenced the complete mitochondrial genome of the Manis pentadactyla (Pholidota: Manidae), which is considered as an endemic species in China. It is listed as a vulnerable species by the International Union for Conservation of Nature and Natural Resources Red List and also an endangered species in China. The genome is 16,578 bp in size. Its gene arrangement pattern was identical with those of Manis tetradactyla. We compared the mitochondrial genome of M. pentadactyla with that of the M. tetradactyla. Nucleotide sequence similarity between the two whole mitochondrial genomes was 79.30%, and the relatively low similarity seems to indicate that the two species are distinctly separated on the species level. The information on the mitochondrial genome comparison of the two species was discussed in detail in this paper.

Design of water gas shift catalysts for hydrogen production in fuel processors

Low sulfur hydrocarbon fuels can be converted to fuel cell grade H(2) using a compact fuel processor architecture. The necessary high volumetric activity water gas shift (WGS) Pt on ceria-zirconia catalysts reacts CO-rich reformate with steam to yield H(2) and CO(2). Such highly selective, non-pyrophoric noble metal/Ce([1-(x+y)])Zr(x)Dp(y)O(2) catalysts were developed through coordinated atomic modeling, syntheses, structural characterization, kinetic performance tests, and micro-kinetic analyses. Density functional simulations made with the VASP code suggested that the undoped catalyst WGS activity would be limited by the strong binding of CO intermediates, blocking the reoxidation of the reduced oxide by water. These predictions were confirmed by in situ cylindrical internal reflection-Fourier transform infrared spectroscopy and by micro-kinetic analyses of the micro-reactor results. Atomic simulations were used to evaluate the impact transition metal dopants had on the surface chemistry of cubic ceria-zirconia. VASP predicted that acidic transition metal dopants such as Nb, Mo, Ta, and W would increase the oxide surface affinity for water and thus increase the turnover rate of the catalyst. The efficacy of Mo-doped ceria-zirconia compositions was confirmed at lower temperatures in replicated catalyst synthesis-reactor studies.

[Microbiological investigations of high-temperature horizons of the Kongdian petroleum reservoir in connection with field trial of a biotechnology for enhancement of oil recovery]

The physicochemical conditions and microbiological characteristics of the formation waters of the Kongdian bed of the Dagang oil field (China) were studied. It was demonstrated that this bed is a high-temperature ecosystem with formation waters characterized by low mineralization. The concentrations of nitrogen and phosphorus compounds, as well as of electron acceptors, are low. Oil and oil gas are the main organic matter sources. The bed is exploited with water-flooding. The oil stratum was inhabited mostly by anaerobic thermophilic microorganisms, including fermentative (10(2)-10(5) cells/ml), sulfate-reducing (0-10(2) cells/ml), and methanogenic (0-10(3) cells/ml) microorganisms. Aerobic bacteria were detected mainly in the near-bottom zone of injection wells. The rate of sulfate reduction varied from 0.002 to 18.940 microg S(2-) l(-1) day(-1) and the rate of methanogenesis from 0.012 to 16.235 microg CH4 l(-1) day(-1). Microorganisms with great biotechnological potential inhabited the bed. Aerobic thermophilic bacteria were capable of oxidizing oil with the formation of biomass, the products of partial oxidation of oil (volatile acids), and surfactants. During growth on the culture liquid of oiloxidizing bacteria, methanogenic communities produced methane and carbon dioxide, which also had oil-releasing capabilities. Using various labeled tracers, the primary filtration flows of injected solutions at the testing site were studied. Our comprehensive investigations allowed us to conclude that the tested method for microbial enhancement of oil recovery based on the activation of the stratal microflora can be applied in the Kongdian bed horizons.

[Microbiological and production characteristics of the high-temperature Kongdian bed revealed during field trial of biotechnology for the enhancement of oil recovery]

Microbiological technology for the enhancement of oil recovery based on the activation of the stratal microflora was tested in the high-temperature horizons of the Kongdian bed (60 degrees C) of the Dagang oil field (China). This biotechnology consists in the pumping of a water-air mixture and nitrogen and phosphorus mineral salts into the oil stratum through injection wells in order to stimulate the activity of the stratal microflora which produce oil-releasing metabolites. Monitoring of the physicochemical, microbiological, and production characteristics of the test site has revealed large changes in the ecosystem as a result of the application of biotechnology. The cell numbers of thermophilic hydrocarbon-oxidizing, fermentative, sulfate-reducing, and methanogenic microorganisms increased 10-10 000-fold. The rates of methanogenesis and sulfate reduction increased in the near-bottom zone of the injection wells and of some production wells. The microbial oil transformation was accompanied by the accumulation of bicarbonate ions, volatile fatty acids, and biosurfactants in the formation waters, as well as of CH4 and CO2 both in the gas phase and in the oil. Microbial metabolites promoted the additional recovery of oil. As a result of the application of biotechnology, the water content in the production liquid from the test site decreased, and the oil content increased. This allowed the recovery of more than 14000 tons of additional oil over 3.5 years.

Augmentation of apoptosis and tumor regression by flavopiridol in the presence of CPT-11 in Hct116 colon cancer monolayers and xenografts

CPT-11, a DNA topoisomerase I inhibitor, has demonstrated clinical activity in colorectal cancer. Flavopiridol, a cyclin-dependent kinase inhibitor, is rapidly emerging as a chemotherapy modulator. To enhance the therapeutic index of CPT-11 in colon cancer, we studied the combination of these two drugs in relatively resistant human colon cancer cells, Hct116. Exposure of parental Hct116 cells to clinically achievable concentrations of SN-38 (the active metabolite of CPT-11) induces p21 and a G(2) arrest. However, these conditions fail to induce apoptosis. In contrast, Hct116 cells that are p21 deficient (p21-/- Hct116) readily undergo apoptosis after treatment with SN-38. In this study we show that the parental Hct116 cells can be sensitized to undergo apoptosis by the addition of flavopiridol after SN-38 treatment. The induction of apoptosis was greatest with sequential therapy consisting of SN-38 followed by flavopiridol. Clonogenic assays also showed greatest inhibition with this sequence. Sequential treatment with SN-38 followed by flavopiridol was associated with higher activation of caspase-3 and greater cleavage of both p21 and XIAP, an inhibitor of apoptosis, compared with other treatment schedules. CPT-11 induced some tumor regressions but no complete responses in the p21-intact Hct116 xenografts. CPT-11 with flavopiridol more than doubled tumor regression, compared with CPT-11 alone, and produced a 30% complete response rate. Our studies indicate that CPT-11 induces cell cycle arrest rather than cell death and that flavopiridol, by activating the caspase cascade, cleaves the inhibitors of apoptosis and sensitizes the cells to undergo cell death. Thus, flavopiridol combined with CPT-11 may provide a completely new therapeutic approach in the treatment of colon cancer.

Experimental therapeutics with a new 10-deazaaminopterin in human mesothelioma: further improving efficacy through structural design, pharmacologic modulation at the level of MRP ATPases, and combined therapy with platinums

Studies described here sought to evaluate the therapeutic potential of a new 10-deazaaminopterin analogue, 10-propargyl-10-deazaaminopterin (PDX), alone and in combination with platinum compounds in the treatment of human pleural mesothelioma. In vitro studies documented 25-30-fold and 3-fold, respectively, greater cytotoxic potency of PDX compared with methotrexate and another 10-deazaaminopterin, edatrexate, against VAMT-1 and JMN cell lines derived from human mesothelioma. These tumor cell lines were also inhibited by platinum compounds. Cisplatin (CDDP) was somewhat more inhibitory than oxaloplatin and >1 log order in magnitude more inhibitory than carboplatin (CBCDA). Against the JMN tumor xenografted in nude mice, whereas methotrexate and, more so, edatrexate, were potently growth inhibitory, only PDX brought about substantial regression. By comparison, CDDP and CBCDA, but not oxaloplatin were markedly growth inhibitory to this same tumor in vivo. This high level of therapeutic activity of PDX could be additionally enhanced by coadministration of probenecid, an inhibitor of canicular multispecific organic anion transporter/multidrug resistance-related protein (MRP)-like ATPases, which increased the number of complete regressions by >-3 fold. Canicular multispecific organic anion transporter/MRP genes, primarily 1, 3, 4, 5, and 7, were in fact expressed in these human mesothelioma cell lines as determined by real-time reverse transcription-PCR. These same MRP genes, including, to a lesser extent, MRP-4, were also expressed in pleural mesotheliomas derived from patients as shown by the same methodology. When combined with CDDP or CBCDA, PDX achieved 2-fold greater overall regression of the JMN tumor with a 3-4-fold increase in complete regressions, although some attenuation of dosages of each were required in the combination. These results strongly suggest that PDX has significant potential in the treatment of human pleural mesothelioma, particularly when coadministered with probenecid or combined with platinum compounds.

[A pathological comparison between Hirschsprung's enterocolitis and neonate necrotizing enterocolitis]

Autopsy records of 9 cases of neonate Hirschsprung's enterocolitis (HD) and 16 cases of neonate necrotizing enterocolitis (NEC) were analysed. It was found that the NEC lesions were more extensive than HD lesions, the bleeding and inflammation in NEC were also more serious than in HD. From our 21 animal experiments in which we tried to clarify the pathogenesis of Hirschsprung's enterocolitis and NEC, our preliminary hypothesis fro the development of Hirschsprung's enterocolitis being: the distal segment was first obstructed, causing the proximal segment to expand, the increase of pressure within the bowel resulted in ischemia of the intestines, increased bacterial multiplication in the retained feces and bacterial infiltration of the intestinal mucosa. The above being the major cause of HD. When the neonate is in asphyxia or shock, ischemia of the intestines and immunoallergic reactions occur, due to the lack of IgA in the mucosa, the multiplication and infiltration of pathogenic enterobacteria in the intestinal wall results in NEC.