[Analysis of relationship between (18)F-FDG PET/CT SUVmax of esophageal squamous cell carcinoma before treatment and postoperative survival]

Objective: To evaluate the value of (18)F-FDG PET/CT in predicting long-term survival of esophageal squamous cell carcinoma(ESCC) before initial treatment. Methods: A total of 167 ESCC patients were retrospectively analyzed who underwent surgery between January 2010 and December 2014 in prospective database of Peking University Cancer Hospital Thoracic Surgery Department One, all cases were included according to inclusion and exclusion criteria.The relationship between SUVmax of the primary tumor and patients' age, gender, tumor location, tumor differentiation, tumor regression grade as well as long term survival were compared. Results: The median follow-up time of the 167 cases was 46.9 months(ranging from 30.5 to 86.2 months), with 1 year and 3 years postoperatively being 95.1% and 68.4%, respectively.The SUVmax of the tumor was positively correlated with cT(P<0.01), cN(P=0.033), cTNM(P=0.002) and pTNM(P=0.003)of the tumor.Patients with SUVmax ≤6 obtained a survival significantly better compared with patients with SUVmax>6, the 3 years OS were 83.4 % vs 65.6% (P=0.02) , and DFS were 82.4% vs 55.4%(P=0.006), respectively.The multivariate regression analysis demonstrated that the SUVmax>6 before treatment was the independent prognostic factor for OS (HR=3, 95%CI 1.050-8.568) and DFS (HR=3.971, 95% CI 1.408-11.200) of the ESCC patients. Conclusions: The higher the (18)F-FDG PET/CT SUVmax of the ESCC primary tumor, the poorer survival of the patients. Therefore, SUVmax could be used as an indicator to predict long term survival of the ESCC patients before treatment.

Tetramethylpyrazine inhibited hypoxia-induced expression of calcium-sensing receptors in pulmonary artery smooth muscle cells in chickens

Tetramethylpyrazine (TMP) is a biologically active ingredient, which is isolated from a popularChinese medicinal plant. It has been used effectively to treat ischemic heart problems, cerebrovascular and thrombotic vascular diseases. This study was designed to evaluate the effect of TMP on calciumsensing receptors in pulmonary artery smooth muscle in chickens. For this purpose forty day-old chicks were distributed into five groups: the control group, the hypoxia group (kept under low Oxygen treatment), and TMP groups (kept under low Oxygen treatment along with treatment of different concentrations of TMP). The pulmonary artery smooth muscle cells were also cultured on 6-well plates in high glucose culture medium and divided into the same five groups. We used in vivo and in vitro study models by applying immunohistochemistry, RT-qPCR assay and Western blotting analysis. Our results showed that pre-incubation with hypoxia markedly stimulated the activation of calcium-sensing receptor (CaSR) in pulmonary artery smooth muscle cells (PASMCs). The TMP decreased the mRNA and protein levels of CaSR. Treatment with TMP clearly inhibited the activation of all CaSR in a dose-dependent manner. Our data demonstrated that TMP can down-regulate the expression of CaSR. Therefore, these findings provide a new target to treat pulmonary arterial hypertension (PAH) under hypoxic conditions.

Altered Regional Homogeneity in Chronic Insomnia Disorder with or without Cognitive Impairment

BACKGROUND AND PURPOSE

Many studies have shown that insomnia is an independent factor in cognitive impairment, but the involved neurobiological mechanisms remain unclear. We used regional homogeneity to explore the specific neurobiologic indicators of chronic insomnia disorder with mild cognitive impairment.

MATERIALS AND METHODS

Thirty-nine patients with insomnia were divided into a group with and without cognitive impairment; we also included a control group (n = 28). Abnormalities in brain functional activity were identified by comparing the regional homogeneity values for each brain region among the groups.

RESULTS

Subjective insomnia scores were negatively correlated with cognitive impairment after controlling for age, sex, and educational effects. Regions with significant differences in regional homogeneity values in the 3 groups were concentrated in the right medial prefrontal cortex, the right superior frontal gyrus, and the left superior occipital gyrus. Meanwhile, subjective insomnia scores were negatively correlated with the strength of the decreased regional homogeneity in the right medial prefrontal cortex. The increased regional homogeneity value in the right superior frontal gyrus was positively correlated with the Montreal Cognitive Assessment score in patients.

CONCLUSIONS

Our results indicate that decreased regional homogeneity values in the medial prefrontal cortex and increased regional homogeneity values in the cuneus may be important neurobiologic indicators of chronic insomnia disorder and accompanying cognitive impairment. Overall, our study described the regional homogeneity of the whole brain in chronic insomnia disorder with mild cognitive impairment and could be the basis for future studies.

Abstract P5-07-05: LOC283299 suppress the lymphnode metastatic cascade in breast cancer patients

Background

Long non-coding RNAs (lncRNAs) have been proved to play an essential role in cancer metastasis. The accuracy of intraoperative assessment of lymph nodes metastasis need to be improved. In this study, we aimed to define the lncRNA biomarker ectopic expressed in breast cancer patients' metastatic lymph nodes, and to explore the potential molecular mechanisms.

Experimental Design

RNA-seq analyses in 3 paired breast cancer patients' primary tumor and metastatic lymph node was used as training set to determine differentially expressed lncRNAs that may be associated with lymph node metastasis. The other 40 patients were analyzed as validation set to test the accuracy of lncRNAs identification by quantitative real-time PCR. The correlation between LOC283299 expression level and prognosis in other 282 breast cancer patients was confirmed. In parallel, in vitro and in vivo analyses were carried out to determine the potential mechanisms of LncRNA-dependent lymph node metastases and prognosis.

Results

RNA-seq analyses in the training set revealed significant correlation between high expression level of LOC283299 and lower lymph node metastasis potential in breast cancer patients. We further validated that the expression level of LOC283299 was significantly higher in tumor primary tissue than that in paired metastatic lymph node (P=0.0245), and higher LOC283299 expression level was markedly associated with good metastasis-free survival in breast cancer patients (P=0.04). In breast cancer cell lines, CRISPR-on overexpression of LOC283299 inhibited proliferation, migration, invasion, and metastases both in vivo and in vitro. shRNA knockdown LOC283299 promotes the ability of tumor proliferation and metastasis. The molecular mechanisms by which LOC283299 as metastasis-suppressing lncRNAs regulates recurrence and metastasis may involve regulation of epithelial to mesenchymal transition (EMT), cellular invasion and microenvironment in breast cancer cells.

Conclusion

Our study revealed a strong correlation between LOC283299 expression and lymph node metastases in breast cancers. High level of LOC283299 was associated with better metastasis-free survival. The changed metastasis phenotype may be mediated by the interaction of LOC283299 and breast cancer cells. Therefore, LOC283299 may represent a potential predictive biomarker for early lymph node metastasis in breast cancer.

Citation Format: Guo R, Xue J, Su Y, Xiu B, Ji W, Chi Y, Wu J. LOC283299 suppress the lymphnode metastatic cascade in breast cancer patients [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-07-05.

Abstract P3-01-06: Can axillary evaluation be omitted in patients preoperatively diagnosed with ductal carcinoma in situ by core needle biopsy?

Background

Patients diagnosed with ductal carcinoma in situ (DCIS) by core needle biopsy (CNB) have a great chance of upgrading invasive cancer on the final pathology. Positive axillary lymph nodes can be found in these patients. The present study sought to identify clinicopathological factors associated with upgrading and axillary lymph nodes metastasis in patients preoperatively diagnosed with DCIS by CNB.

Materials and Methods

This study identified 604 patients (cT1-3N0M0) with preoperative diagnosis of pure DCIS by CNB who had undergone axillary evaluation from August 2006 to December 2015 at Fudan University Shanghai Cancer Center (FUSCC). Predictors of upgrading and axillary lymph nodes metastasis were analyzed, respectively.

Results

Of all 604 patients, 513 (84.93%) and 91 (15.07%) patients had undergone sentinel lymph nodes biopsy (SLNB) and axillary lymph nodes dissection (ALND), respectively. Overall, 121 (20.03%) and 193 (31.95%) patients were upgraded to DCIS with microinvasion (DCISM) and IDC on final pathology, respectively. Positive axillary lymph nodes were identified in 41 (6.79%) patients, of which 35 (5.80%) patients had 1-2 positive axillary lymph nodes, 6 (0.99%) patients had 3 or more positive axillary lymph nodes. Among patients with axillary lymph nodes metastasis, 4 (9.76%), 4 (9.76%) and 33 (80.48%) patients were in DCIS, DCISM and IDC group, respectively. Predictors of upgrading included tumor size on ultrasonography (P=0.001), Ki-67 (P=0.046) and molecular subtype (P=0.007) in univariate analysis. In multivariate analysis, patients with larger tumor size on ultrasonography (&gt;2cm) (OR 1.767, P=0.001) were more likely to be upgraded on final pathology. Also, ER+ HER2+ patients were more likely to be upgraded than ER+ HER2- patients (OR 1.659, P=0.047). Factors associated with axillary lymph nodes metastasis included nipple discharge (P&lt;0.001), tumor size on pathology (P=0.037), number of lesions (P=0.039), axillary evaluation methods (P=0.029) and molecular subtype (P=0.049) in univariate analysis. Whereas, only nipple discharge and larger tumor size on pathology (&gt;2cm) reached statistical significance in multivariate analysis (OR 5.959, P&lt;0.001; OR 2.361, P=0.042). In addition, further analysis showed upgrading on final pathology had a significant influence on axillary lymph nodes status (P&lt;0.001). However, this correlation was not shown between patients with DCIS and DCISM in pairwise comparison.

Conclusion

The data of upgrading and axillary lymph nodes metastasis in patients with an initial diagnosis of DCIS by CNB was comparable in this cohort with published data. Despite of a 51.98% upgrading rate, the rate of axillary lymph nodes metastasis in these patients is low, which supports the omission of axillary evaluation in selected patients.

Citation Format: Si J, Yang B, Guo R, Huang N, Quan C, Chen J, Wu J. Can axillary evaluation be omitted in patients preoperatively diagnosed with ductal carcinoma in situ by core needle biopsy? [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-01-06.

[Dynamics of F1 antibody responses to Yersinia pestis infection in Rhombomys opimus]

Objective: To observe the dynamics of antibody response in great gerbils infected with Yersinia pestis in experiment. Method: A total of 211 great gerbils were captured in the southern margin of plague natural focus of Junggar Basin of the Xinjiang Uygur Autonomous Region in 2011. Among them, there were 167 great gerbils without infection of Y. pestis and 44 great gerbils infected by Y.pestis. Y.pestis No. 2504 was employed for this experimental strain, which was strong toxic strain with negativity in the reduction experiment of nitrate. 35 great gerbils without the infection of Y. pestis were divided randomly and averagely into 7 groups including 6 experimental groups and 1 control group. Great gerbils in the 1st to 6th experimental groups were exposed first with 1 × 10(6)-1 × 10(11) CFU/ml of bacterial fluid with 10 times of gradient dilution; groin areas of great gerbils in the control group were injected subcutaneously with physiological saline; and the amount of infection was all 1 ml. 17 great gerbils infected with Y. pestis and the first detection of F1-antibody titer in 1∶256-1∶4 096 were grouped according to F1-antibody titer: group 1∶4 096 (n=4), group 1∶2 048 (n=4), group 1∶1 024 (n=3), group 1∶512 (n=3) and group 1∶256 (n=3); and blood in caudal regions was collected in asepsis for the detection of F1-antibody, with a total of 5 times. 9 great gerbils which were selected from the remaining great gerbils infected with Y. pestis and detected F1-antibody negative 2 times were exposed 1×10(6) CFU/ml of bacterial fluid for the second infection, with the amount of infection being 1 ml. Blood in caudal regions of great gerbils after the first and second infection were collected for the detection of plague F1-antibody on the 3rd, 5th, 7th, 15th, 30th, 60th, 90th and 120th day after infection. Declined regression models for great gerbils' antibodies were established with unary linear regression equation; declined change diagrams for the antibodies were drawn to observe the declined F1-antibody after great gerbils were exposed to Y. pestis. Results: In great gerbils with the first infection of Y. pestis, antibodies were detected in the 1 × 10(6)-1 × 10(8) CFU/ml of group on the 30th, 15th and 15th day, respectively; the positive rates of antibody were 1/4, 3/4 and 4/5, respectively; the group 1×10(7) and 1× 10(8) CFU/ml reached to the highest antibody titer with 1∶256 on the 120th day; antibodies were revealed in the group 1×10(9), 1×10(10) and 1×10(11) CFU/ml from the 5th to 7th day when the seroconversion of all antibodies was observed; group 1×10(11) CFU/ml reached to the highest antibody titer on the 120th day with 1∶4 096. In the great gerbils with the second exposure to Y.pestis, positive antibodies were detected on the 3rd day with the positive rate being 2/9; and the highest antibody titer with 1∶2 048 was noted on the 90th day. Unary linear regression equation of declined F1 antibody of great gerbils was y=0.045x- 0.321 (F=115.40, P< 0.001), and the shortest duration for F1-antibody titer declining from 1∶4 096 to 0 was 140 d and the longest duration 200 d. Conclusion: Great gerbils infected with the high concentration of Y. pestis fluid show shorter duration in producing F1-antibody, the antibody positive rate is also higher, and the highest antibody titer can reach 1∶4 096. The great gerbils could hold the plague F1 antibodies for a long time which was about 140 to 200 days from the highest titer.

[A high-precision digital images date set of larynx]

Objective:To build a digital cross-sectional images date set of human normal larynx with high-precision.Method:A fresh frozen normal human larynx was embedded using Kawamot's Film Method and then serially sectioned at 10 μm with a LeicaCM3600XP Cryomacrotome, meanwhile digital images of the block surface were recorded after every section with a Nikon D750 camera and stored respectively as JPG and RAW files. All images were cropped to display a constant area on the block surface by photoshop7 and stored as TIFF files. Result:A total of 6 656 images were recorded in 24-bit RGB resolution, the complete data file is 97.5 GB and 174 GB. After elimination of image size variation, all images were re-sampled at a final resolution of 40 μm/pixel and the complete data file is 107 GB. Conclusion:It's feasible to use the combination of Kawamot's Film Method,Digital Single Lens Reflex with high-resolution and regular block face-based alignment to build high-precision digital images date set, which could apply to some partial organs that resemble larynx.

Posttraumatic administration of a sub-anesthetic dose of ketamine exerts neuroprotection via attenuating inflammation and autophagy

As a complex disease, traumatic brain injury (TBI) can result in long-term psychiatric changes and sensorimotor and cognitive impairments. The TBI-induced loss of memory and long-term cognitive dysfunction are related to mechanistic factors including an increased inflammatory response, autophagy, edema, and ischemia. Many published studies have offered evidence for the neuroprotective effects and anti-inflammatory properties of ketamine for TBI patients. Nonetheless, there is a limited understanding of the accurate mechanism that underlies the potential neuroprotective effects of ketamine. Herein, it can be shown that posttraumatic administration of ketamine at a sub-anesthetic dose (10mg/kg ketamine, every 24h up to 7days) can prevent the TBI-induced production of IL-6 and TNF-α, attenuate deficits of dendrites and spines and exert beneficial effects on memory and behavior. Moreover, studies show that ketamine may activate the mTOR signaling pathway by p-mTOR induction to down-regulate the expression of crucial autophagic proteins such as LC3 and Beclin-1. According to these findings, ameliorating secondary brain injury and anti-inflammatory properties is closely related to the neuroprotection of ketamine, which supports the use of ketamine as a potential therapy for patients with TBI to alleviate functional deficits.

[Analysis of association of human 8-oxoguanine giycosylase 1 polymorphism with the susceptibility of laryngeal cancer]

Objective: To study the association between human 8-oxoguanine giycosylase 1 (hOGG1) gene polymorphisms and the risk of laryngeal carcinoma. Methods: A total of 86 patients with laryngeal carcinoma treated in The Air Force General Hospital and the Bozhou People's Hospital of Anhui Province from Jan 2010 to Dec 2014 were included in experimental group, and 86 healthy adults were selected as control group. The hOGG1 gene polymorphisms of subjects in two group were detected with by polymerase chain reaction amplification and gene sequencing technology, the differences in hOGG1 gene polymorphisms between two groups were analyzed. Results: The frequencies of hOGG1 gene heterozygous type (Ser/Cys) and mutant type (Cys/Cys) in experimental group were higher than those in control group(P<0.05). Compared to individuals with hOGG1 gene Ser/Ser, individuals with hOGG1 gene Ser/Cys had a 2.97-fold increased risk of laryngeal carcinoma, and individuals with hOGG1 gene Cys/Cys had a 8.09-fold increased risk of laryngeal carcinoma. Stratified by smoking or not, it was found that the proportion of heterozygous type or mutant type in smokers was higher significantly than non-smokers (P<0.05). Conclusion: Individuals with hOGG1 gene heterozygous type (Ser/Cys) or mutant type (Cys/Cys) have a higher risk of laryngeal carcinoma, with interaction between these gene types and smoking, and the gene types could be used as predictors for the occurrence of laryngeal carcinoma.

Substrate Modulus Regulates Osteogenic Differentiation of Rat Mesenchymal Stem Cells through Integrin β1 and BMP Receptor Type IA

Osteoblast differentiation of mesenchymal stem cells is regulated by both soluble factor (e.g., bone morphogenetic proteins (BMP)) and mechanically transduced signaling, but the mechanisms have only been partially elucidated. In this study, physical association of BMP Receptor I (BMPRI) with integrin β1 sub-unit (Iβ1) was hypothesized to mediate osteoblast differentiation of rat bone marrow-derived mesenchymal stem cells (MSCs) on bone-like substrates. The effects of substrate modulus on osteoblast differentiation of MSCs were investigated for 2D poly(ester urethane) films with moduli varying from 5 - 266 MPa, which spans the range from collagen fibrils to trabecular bone. SMAD1/5 and p44/42 MAPK signaling, expression of markers of osteoblast differentiation, and matrix mineralization increased with increasing substrate modulus. The effects of substrate modulus on osteoblast differentiation were mediated by Iβ1, which was also expressed at higher levels on increasingly rigid substrates. Förster resonance energy transfer (FRET) and immunoprecipitation (IP) experiments showed that physical association of Iβ1 and BMP Receptor I (BMRPRI) increased with substrate modulus, resulting in activation of the BMP signaling pathway. Thus, these studies showed that integrin and BMP signaling converge to regulate osteoblast differentiation of MSCs, which may potentially guide the design of scaffolds and rhBMP-2 delivery systems for bone regeneration.

Controlling Kondo-like Scattering at the SrTiO3-based Interfaces

The observation of magnetic interaction at the interface between nonmagnetic oxides has attracted much attention in recent years. In this report, we show that the Kondo-like scattering at the SrTiO3-based conducting interface is enhanced by increasing the lattice mismatch and growth oxygen pressure PO2. For the 26-unit-cell LaAlO3/SrTiO3 (LAO/STO) interface with lattice mismatch being 3.0%, the Kondo-like scattering is observed when PO2 is beyond 1 mTorr. By contrast, when the lattice mismatch is reduced to 1.0% at the (La0.3Sr0.7)(Al0.65Ta0.35)O3/SrTiO3 (LSAT/STO) interface, the metallic state is always preserved up to PO2 of 100 mTorr. The data from Hall measurement and X-ray absorption near edge structure (XANES) spectroscopy reveal that the larger amount of localized Ti(3+) ions are formed at the LAO/STO interface compared to LSAT/STO. Those localized Ti(3+) ions with unpaired electrons can be spin-polarized to scatter mobile electrons, responsible for the Kondo-like scattering observed at the LAO/STO interface.

Substrate modulus of 3D-printed scaffolds regulates the regenerative response in subcutaneous implants through the macrophage phenotype and Wnt signaling

The growing need for therapies to treat large cutaneous defects has driven recent interest in the design of scaffolds that stimulate regenerative wound healing. While many studies have investigated local delivery of biologics as a restorative approach, an increasing body of evidence highlights the contribution of the mechanical properties of implanted scaffolds to wound healing. In the present study, we designed poly(ester urethane) scaffolds using a templated-Fused Deposition Modeling (t-FDM) process to test the hypothesis that scaffolds with substrate modulus comparable to that of collagen fibers enhance a regenerative versus a fibrotic response. We fabricated t-FDM scaffolds with substrate moduli varying from 5 to 266 MPa to investigate the effects of substrate modulus on healing in a rat subcutaneous implant model. Angiogenesis, cellular infiltration, collagen deposition, and directional variance of collagen fibers were maximized for wounds treated with scaffolds having a substrate modulus (Ks = 24 MPa) comparable to that of collagen fibers. The enhanced regenerative response in these scaffolds was correlated with down-regulation of Wnt/β-catenin signaling in fibroblasts, as well as increased polarization of macrophages toward the restorative M2 phenotype. These observations highlight the substrate modulus of the scaffold as a key parameter regulating the regenerative versus scarring phenotype in wound healing. Our findings further point to the potential use of scaffolds with substrate moduli tuned to that of the native matrix as a therapeutic approach to improve cutaneous healing.

Controlling quantum dot emission by plasmonic nanoarrays

Metallic nanoparticle arrays support localized surface plasmon resonances (LSPRs) and propagating surface lattice resonances (SLRs). We study the control of quantum dot (QD) emission coupled to the optical modes of silver nanoparticle arrays, both experimentally and numerically. With a hybrid lithography-functionalization method, the QDs are deposited in the vicinity of the nanoparticles. Directionality and enhancement of the emission are observed in photoluminescence spectra and fluorescence lifetime measurements, respectively. Similar features are also demonstrated in the numerical simulations. The tunable emission of this type of hybrid structures could lead to potential applications in light sources.

Research on rat models of hypobaric hypoxia-induced pulmonary hypertension

OBJECTIVE

Rat models of hypobaric hypoxia-induced pulmonary hypertension are commonly used in studies of chronic mountain sickness, while there are few researches specially focusing on these rats model. This study aims to exploring possible pathogenesis of hypobaric hypoxia-induced pulmonary hypertension by experimenting on hypobaric hypoxia-induced PH rat models at different simulate- altitudes.

MATERIALS AND METHODS

32 healthy male SD rats were randomly divided into six groups of different degree and time period of hypobaric hypoxia. The mean pulmonary arterial pressure (m PAP), right ventricular pressure (RVSP), the right ventricle (RV), left ventricular (LV), ventricular septal (S), the right ventricular hypertrophy index (RVHI) [calculated under the formula of RV / (LV + S)], hematoxylin-eosin staining, elastic fibers staining, the ratio of the thickness of vascular wall to its outer diameter (MT%), the ratio of the cross-sectional area of the middle vascular wall to the total vascular cross-sectional area (MA%); the α-SMA, and the Ki6 expressions were detected to evaluated the pulmonary hypertension.

RESULTS

There were significant differences of the mPAP, RVSP and RVHI value between the hypobaric hypoxia groups and the control group (p < 0.05). The mPAP, RVSP, RVHI, MT%, MA%, α-SMA, and Ki6 of rats in model groups at an altitude of 3KM were higher than those of the control group, which raised gradually with the number of weeks increasing. The mPAP, RVSP, RV / (LV + S) value, MT%, MA%, α-SMA, and Ki67 of the 5KM-4W group were significantly higher than those of the control group (p < 0.05).

CONCLUSIONS

Rat models with pulmonary hypertension at different altitudes have been successfully established by automatic adjusting hypobaric hypoxia chamber. Exposure to a low oxygen environment at a simulate-altitude of 3 km for 8 weeks have caused the pathological remodeling of pulmonary vascular walls and pulmonary hypertension, and further led to a series of pathological changes, including right ventricular hypertrophy. This model is easy to be replicated with good reproducibility and provides evidence for clinical trial of drugs.

Epitope analysis of Ara h 2 and Ara h 6: characteristic patterns of IgE-binding fingerprints among individuals with similar clinical histories

BACKGROUND

Ara h 2 and Ara h 6 are moderately homologous and highly potent peanut allergens.

OBJECTIVE

To identify IgE-binding linear epitopes of Ara h 6, compare them to those of Ara h 2, and to stratify binding based on clinical histories.

METHODS

Thirty highly peanut-allergic subjects were stratified by clinical history. Sera were diluted to contain the same amount of anti-peanut IgE. IgE binding to overlapping 20-mer peptides of Ara h 2 and Ara h 6 was assessed using microarrays.

RESULTS

Each subject had a unique IgE-binding fingerprint to peptides; these data were coalesced into epitope binding. IgE from subjects with a history of more severe reactions (n = 19) had a smaller frequency of binding events (BEs) for both Ara h 2 (52 BEs of 152 (19X8epitopes) possible BEs and Ara h 6 (13 BEs of 133 (19X7 epitopes) possible BEs) compared to IgE from those with milder histories (n = 11) (Ara h 2: 47 BEs of 88 (11X8 epitopes) possible BEs, P < 0.01; Ara h 6: 25 BEs of 77 (11X7 epitopes) possible BEs, P < 0.001). Using an unsupervised hierarchal cluster analysis, subjects with similar histories tended to cluster. We have tentatively identified a high-risk pattern of binding to peptides of Ara h 2 and Ara h 6, predominantly in subjects with a history of more severe reactions (OR = 12.6; 95% CI: 2.0-79.5; P < 0.01).

CONCLUSIONS AND CLINICAL RELEVANCE

IgE from patients with more severe clinical histories recognize fewer linear epitopes of Ara h 2 and Ara h 6 than do subjects with milder reactions and bind these epitopes in characteristic patterns. Close examination of IgE binding to epitopes of Ara h 2 and Ara h 6 may have prognostic value.

Factors influencing independent oral feeding in preterm infants

OBJECTIVE

Determine the mean post-menstrual age when preterm infants attain independent oral feeding skills and whether gestational age, common neonatal morbidities, gender, race, delivery route, or birth year affects this reflex.

METHODS

A retrospective chart review of 2700 preterm infants, born before 37 weeks gestational age admitted to a level III NICU between January 1978 and July 2013, to determine the post-menstrual age when independent oral feedings occur.

RESULTS

Mean post-menstrual age at achievement of independent oral feeding was 36 + 4/7 weeks ± 14 days. Gestational age under 29 weeks correlated with delayed post-menstrual age at achievement of independent oral feeding at 37 + 3/7 weeks versus 36 + 1/7 weeks for gestational age 29-33 weeks and 36 + 3/7 weeks for late preterm infants (p < 0.0001). Preterm infants with certain morbidities experienced a delay in independent oral feeding: necrotizing enterocolitis at 38 + 6/7 weeks (p < 0.0001), bronchopulmonary dysplasia at 38 + 1/7 weeks (p < 0.0001), severe intraventricular hemorrhage at 37 + 6/7 weeks (p < 0.001). Preterm infants born before the year 2000 achieved independent oral feeding two days later than preterm infants born since the year 2000 (p < 0.0001). Preterm infants delivered vaginally achieved independent oral feeding three days sooner than infants delivered via c-section (p < 0.0001). Female infants orally fed one day sooner than male preterm infants (p = 0.0008).

CONCLUSIONS

Preterm infants achieve independent oral feeding at 36 + 4/7 weeks. Factors negatively influencing when the preterm infant will achieve independent oral feeding include gestational age under 29 weeks and major morbidities, whereas vaginal delivery and ongoing advances in neonatal care may accelerate the transition to independent oral feeding.