[Effect of daily average temperature on the incidence of allergic rhinitis in Lanzhou]

Objective: To evaluate the effect of daily average temperature on the atteck of allergic rhinitis (AR) by analyzing the changes of the outpatient visits of AR in Lanzhou. Methods: The meteorological and air pollution data of Lanzhou City and the outpatient visits of AR in Departments of Otorhinolaryngology and head and neck surgery of The First Hospital of Lanzhou University, The Second Hospital of Lanzhou University and Gansu Provincial People's Hospital from 2013 to 2017 were collected to describe the meteorological factors, air pollutants and the outpatient visits of AR. The correlation among the three factors was then analyzed by Spearman rank correlation analysis. Using the distributed lag non-linear model, the relationship between daily average temperature and the number of daily outpatient visits of AR was studied and stratified by gender and age with the long-term trend, seasonal trend and other confounding factors controlled. Results: From 2013 to 2017, the outpatient visits of AR in the above three hospitals reached 20 008 person times. Daily average temperature in Lanzhou showed a non-linear correlation to the outpatient visits of AR, with a certain lag effect. When the daily average temperature was 22 ℃ and the cumulative lag was 21 days (lag 0-21 d), the relative risk (RR) peaked at 4.851 (95%CI: 3.986-5.904). The effect of relatively low temperature (2.3 ℃, P₂₅), relatively high temperature (19.8 ℃, P₇₅) and high temperature (25.5 ℃, P₉₅) on lag 0-21 d were the highest, which were 1.761 (95%CI: 1.375-2.255), 4.299 (95%CI: 3.574-5.171) and 3.656 (95%CI: 3.046-4.389), respectively. According to the stratified analysis, low and relatively low temperature had more significant effect on the outpatient visits of AR among women and people aged 0-14 years. When lag was 0-21 days, the RR value of low temperature for female outpatient visits of AR was 1.433 (95%CI: 1.105-1.860); the RR value of relatively low temperature for female outpatient visits of AR was 1.879 (95%CI: 1.460-2.419); the RR value of low temperature for AR outpatient visits for people aged 0-14 years was 1.511 (95%CI: 0.999-2.287), the RR value of relatively low temperature for AR outpatient visits for people aged 0-14 years was 2.051 (95%CI: 1.383-3.042). Relatively high temperature, on the other hand, had a more significant effect on men and people aged 15-59 years. High temperature had a greater impact on the number of AR outpatients in men and people aged 0-14 years. Conclusions: Temperature may be an important influencing factor of AR onset in Lanzhou. At relatively high temperature (19.8 ℃), the risk of AR outpatient visits is significantly increased, and the cumulative lagged effects are observed. The sensitivity of AR patients to temperature is different in different genders and ages.

[The inhibition of 18β-sodium glycyrrhetinic acid on thymic stromal lymphopoietin expression in the nasal mucosa of allergic rhinitis rats]

Objective: To explore the effect of 18β-sodium glycyrrhetinic acid on thymic stromal lymphopoietin (TSLP) in nasal mucosa of allergic rhinitis (AR) rats. Methods: One hundred Wistar rats,half male and half female,were randomly divided into 5 groups by random number table method: control group, AR model group,budesonide group,18β-sodium glycyrrhetinic acid at dose of 20 mg/kg and 40 mg/kg groups, with 20 rats in each group. AR animal models were established by ovalbumin (OVA) sensitization in the other four experimental groups. After successful modeling, budesonide and 18β-sodium glycyrrhetinic acid were given in each group,and the detection time points were 2 weeks and 4 weeks. The distribution of TSLP in rat nasal mucosa was detected by immunohistochemistry,and the expression of TSLP in rat nasal mucosa was determined by Western blot at the protein level. The expression of TSLP-mRNA in rat nasal mucosa was detected and compared by real-time fluorescence quantitative PCR (RT-PCR) at mRNA level. The concentrations of IL-4 and OVA-sIgE in rat serum were measured and compared by ELISA. One-way analysis of variance and the least significant difference method were used for the comparison among groups, LSD t test was used for the comparison between the two groups,and the difference was statistically significant (P<0.05). Results: Immunohistochemistry confirmed existence of TSLP in rat nasal mucosa, especially in epithelial cells,endothelial cells and epithelial cilia. Western blot and RT-PCR suggested that the expression of TSLP and TSLP-mRNA in nasal mucosa of AR model group was significantly higher than that of control group (2 weeks TSLP: 1.795 9±0.131 4 vs 0.990 5±0.164 2, 4 weeks TSLP: 1.809 7±0.253 4 vs 0.870 3±0.124 4; 2 weeks TSLP-mRNA:4.582 9±0.697 7 vs 1.108 7±0.081 1, 4 weeks TSLP-mRNA:4.814 4±0.662 8 vs 1.001 0±0.155 3; all P<0.05). After 2 weeks and 4 weeks of drug intervention,the expression of TSLP and TSLP-mRNA was inhibited in nasal mucosa of budesonide group,18β-sodium sodium glycyrrhetinic acid at dose of 20 mg/kg and 40 mg/kg group,which was significantly different from that of AR model group (2 weeks TSLP: (0.897 8±0.081 8)/(1.072 1±0.113 6)/(1.396 6±0.133 9) vs 1.795 9±0.131 4; 4 weeks TSLP: (1.191 0±0.161 3)/(1.141 0±0.152 3)/(1.200 5±0.189 6) vs 1.809 7±0.253 4; 2 weeks TSLP-mRNA: (1.175 6±0.100 9)/(1.254 4±0.078 2)/(2.037 2±0.559 2) vs 4.582 9±0.697 7; 4 weeks TSLP-mRNA: (1.158 3±0.104 3)/(1.224 0±0.034 0)/(1.275 2±0.099 6) vs 4.814 4±0.662 8; all P<0.05), and not significantly different from control group. With the inhibition of TSLP, the concentrations of IL-4 and OVA-sIgE in rat serum were also decreased. Conclusion: 18β-sodium glycyrrhetinic acid has obvious inhibitory effect on TSLP in nasal mucosa of AR rats, which can control Th2 type immune inflammatory reaction.

[Effects of 18β-sodium glycyrrhetinic acid on TNF-α expression in rats with allergic rhinitis]

Objective:To observe the effect of 18β-sodium glycyrrhetinic acid(18β-SGA) on the expression of TNF-α in nasal mucosa of rats with allergic rhinitis（AR）, and explore the intervention mechanism of 18β-SGA on AR. Method:One hundred and six SPF-level Wistar rats were randomly divided into control group, AR group, budesonide group, 18β-SGA low dose group and high dose group. After the AR rat model was constructed by ovalbumin, the rats were given drug intervention and sacrificed after 2 and 4 weeks of intervention. The nasal mucosa of the rats was taken for immunohistochemical staining, RT-qPCR and Western-blotting to localize and quantify the expression of TNF-α. Result:By immunohistochemistry, Western-blotting and RT-PCR, TNF-α was mainly found in the columnar epithelium, vascular endothelium, glandular and some inflammatory cytoplasm of nasal mucosa. And the expression of TNF-α in the nasal mucosa of AR rats was significantly increased than the normal group at the protein and mRNA levels (P<0.01). After intervention with different doses of 18β-SGA, the expression of TNF-α was significantly decreased (P<0.01), especially after 4 weeks of 18β-SGA low dose group(P<0.01). Conclusion:Different doses of 18β-SGA have therapeutic effects on AR, and its mechanism of action may be related to the inhibition of TNF-α expression.

[Internal carotid artery injury during endoscopic endonasal surgery: 3 cases report]

Three cases of internal carotid artery (ICA) injury during endoscopic endonasal surgery were analyzed, including 1 case of recurrent malignancy of sphenoid sinus, 1 case of intraorbital meningioma and 1 case of optic neuropathy. Salvage sphenoid sinus packing with gauze strip was managed in all the three cases. One patient operated a permanent closure of the carotid system intraoperatively and died after surgery. Among 2 survival cases, one patient accepted the endovascular embolization subsequently; the other patient was cured by intravaseular stent graft implantation without craniocerebral or ocular complicatitms.

Three-vessel-trachea view in the diagnosis of fetal cardiac great vessel malformation

Fetal cardiac great vessel malformation is attracting increasing attention in the prenatal ultrasonic diagnosis of fetal congenital heart disease. To investigate the clinical diagnostic values of three-vessel-trachea view (3VT view) in the ultrasonic diagnosis of this malformation, the present study analyzed the echocardiographic examination results of 77 fetuses with great vessel malformation, retrospectively analyzed the echocardiographic characteristics in the three-vessel-trachea view, and followed up the enrolled cases. The results suggest that great vessel malformation had characteristic manifestations, such as abnormal arrangement order, inner diameter, blood flow direction and branch. Color Doppler flow imaging found V, O, C, U, Ioo and oVo structures. There were 20 cases of blood vessel position abnormality, 38 cases of abnormal blood vessel diameter, and 19 cases of abnormal number of blood vessels. The detection rate of abnormal blood vessel diameter was 95%, which was the highest; the detection rate of abnormal blood vessel position was 97.4%, and that of abnormal number of blood vessels was 84.2%. It is concluded that the 3VT view can indicate fetal cardiac great vessel malformation. The 3VT view is beneficial to timely prenatal diagnosis, relief of body pain and improvement of quality of birth.

Repression of Stress-Induced LINE-1 Expression Protects Cancer Cell Subpopulations from Lethal Drug Exposure

Maintenance of phenotypic heterogeneity within cell populations is an evolutionarily conserved mechanism that underlies population survival upon stressful exposures. We show that the genomes of a cancer cell subpopulation that survives treatment with otherwise lethal drugs, the drug-tolerant persisters (DTPs), exhibit a repressed chromatin state characterized by increased methylation of histone H3 lysines 9 and 27 (H3K9 and H3K27). We also show that survival of DTPs is, in part, maintained by regulators of H3K9me3-mediated heterochromatin formation and that the observed increase in H3K9me3 in DTPs is most prominent over long interspersed repeat element 1 (LINE-1). Disruption of the repressive chromatin over LINE-1 elements in DTPs results in DTP ablation, which is partially rescued by reducing LINE-1 expression or function.

[The diagnosis and treatment of primary thyroid lymphoma]

Primary thyroid lymphoma (PTL) refers to the malignant tumor of primary lymphoid tissue in the thyroid, accounting for approximately 5% of all thyroid malignancies and less than 3% of all extranodal lymphomas. PTL usually develops in females more than 50 years old. Most of PTL cases are non-Hodgkin's lymphomas. The major pathological subtypes are mucosa-associated lymphoid tissue lymphoma and diffuse large B-cell lymphoma. Treatment options for individual pathological subtypes are also different, so pathological diagnosis is very important. The main treatment options include surgical treatment, radiotherapy, chemotherapy, targeted therapy and combined therapy. The main aims of surgical treatment are to obtain a determined diagnosis and to relieve airway pressure, . The prognosis of PTL is generally excellent.

Occupancy by key transcription factors is a more accurate predictor of enhancer activity than histone modifications or chromatin accessibility

Background

Regulated gene expression controls organismal development, and variation in regulatory patterns has been implicated in complex traits. Thus accurate prediction of enhancers is important for further understanding of these processes. Genome-wide measurement of epigenetic features, such as histone modifications and occupancy by transcription factors, is improving enhancer predictions, but the contribution of these features to prediction accuracy is not known. Given the importance of the hematopoietic transcription factor TAL1 for erythroid gene activation, we predicted candidate enhancers based on genomic occupancy by TAL1 and measured their activity. Contributions of multiple features to enhancer prediction were evaluated based on the results of these and other studies.

Results

TAL1-bound DNA segments were active enhancers at a high rate both in transient transfections of cultured cells (39 of 79, or 56%) and transgenic mice (43 of 66, or 65%). The level of binding signal for TAL1 or GATA1 did not help distinguish TAL1-bound DNA segments as active versus inactive enhancers, nor did the density of regulation-related histone modifications. A meta-analysis of results from this and other studies (273 tested predicted enhancers) showed that the presence of TAL1, GATA1, EP300, SMAD1, H3K4 methylation, H3K27ac, and CAGE tags at DNase hypersensitive sites gave the most accurate predictors of enhancer activity, with a success rate over 80% and a median threefold increase in activity. Chromatin accessibility assays and the histone modifications H3K4me1 and H3K27ac were sensitive for finding enhancers, but they have high false positive rates unless transcription factor occupancy is also included.

Conclusions

Occupancy by key transcription factors such as TAL1, GATA1, SMAD1, and EP300, along with evidence of transcription, improves the accuracy of enhancer predictions based on epigenetic features.

Electronic supplementary material

The online version of this article (doi:10.1186/s13072-015-0009-5) contains supplementary material, which is available to authorized users.

dCaP: detecting differential binding events in multiple conditions and proteins

BACKGROUND

Current ChIP-seq studies are interested in comparing multiple epigenetic profiles across several cell types and tissues simultaneously for studying constitutive and differential regulation. Simultaneous analysis of multiple epigenetic features in many samples can gain substantial power and specificity than analyzing individual features and/or samples separately. Yet there are currently few tools can perform joint inference of constitutive and differential regulation in multi-feature-multi-condition contexts with statistical testing. Existing tools either test regulatory variation for one factor in multiple samples at a time, or for multiple factors in one or two samples. Many of them only identify binary rather than quantitative variation, which are sensitive to threshold choices.

RESULTS

We propose a novel and powerful method called dCaP for simultaneously detecting constitutive and differential regulation of multiple epigenetic factors in multiple samples. Using simulation, we demonstrate the superior power of dCaP compared to existing methods. We then apply dCaP to two datasets from human and mouse ENCODE projects to demonstrate its utility. We show in the human dataset that the cell-type specific regulatory loci detected by dCaP are significantly enriched near genes with cell-type specific functions and disease relevance. We further show in the mouse dataset that dCaP captures genomic regions showing significant signal variations for TAL1 occupancy between two mouse erythroid cell lines. The novel TAL1 occupancy loci detected only by dCaP are highly enriched with GATA1 occupancy and differential gene expression, while those detected only by other methods are not.

CONCLUSIONS

Here, we developed a novel approach to utilize the cooperative property of proteins to detect differential binding given multivariate ChIP-seq samples to provide better power, aiming for complementing existing approaches and providing new insights in the method development in this field.

Abstract P2-11-15: Development of a web-based survey tool to assess change in breast cancer (BrCa) survivor knowledge after receipt of cancer treatment summary and survivorship care plan (SCP)

Intro: The Institute of Medicine advocates survivorship care plans (SCPs) as tools to improve coordination of care by improving survivor knowledge of follow-up recommendations and future risks. No evidence exists to demonstrate that SCPs impact survivor knowledge of diagnosis, treatment, or future/chronic side effects. Furthermore, there is a lack of information on existing surveys and their ability to assess survivor knowledge regarding these issues, without change over time. The purpose of this research is to report on the development of a survey assessing knowledge of diagnosis, treatment, and side effects in BrCa survivors.

Methods: Using existing literature, two oncologists created 24 questions addressing knowledge of diagnosis, treatment, and side effects. Content experts including breast oncology providers (representing multiple subspecialties), Survey Research Shared Service (SRSS) and patient advocates reviewed and revised the questions. Next, potential questions were administered in a group setting to BrCa survivors to evaluate clarity of instructions and survey wording. The Breast Cancer Knowledge (BreaCK) survey was further revised based on survivor feedback.

For pilot testing, BrCa survivors were recruited from clinic to test BreaCK survey content and clarity. Survey 1 was administered in clinic online. SRSS conducted verbal assessments regarding content after Survey 1. Four weeks later, survivors received Survey 2 via email and answered online. Correct answers were abstracted from the medical record.

Results: Nine subjects completed both surveys. Qualitatively, little intra-subject variation was seen between surveys. Subjects did not feel that the survey was burdensome or intrusive. No subject was able to correctly answer all questions. Final survey adjustments were made based on subject feedback and common incorrect answers encountered when grading the surveys. Specifically, subjects had difficulty understanding “endocrine or hormone therapy.” Furthermore, subjects reported guessing in response to some questions – additional answer categories were added, including “I don't know.”

Conclusion: Survivor knowledge did not change significantly between surveys. This suggests survivor knowledge was not impacted by the survey over the four-week interval. The revised BreaCK survey may be a useful tool for assessing survivor knowledge of diagnosis, treatment and side effects. A larger cohort of BrCa survivors is being recruited, starting Summer 2012, and will be evaluated using the survey.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-11-15.

Dynamics of the epigenetic landscape during erythroid differentiation after GATA1 restoration

Interplays among lineage-specific nuclear proteins, chromatin modifying enzymes, and the basal transcription machinery govern cellular differentiation, but their dynamics of action and coordination with transcriptional control are not fully understood. Alterations in chromatin structure appear to establish a permissive state for gene activation at some loci, but they play an integral role in activation at other loci. To determine the predominant roles of chromatin states and factor occupancy in directing gene regulation during differentiation, we mapped chromatin accessibility, histone modifications, and nuclear factor occupancy genome-wide during mouse erythroid differentiation dependent on the master regulatory transcription factor GATA1. Notably, despite extensive changes in gene expression, the chromatin state profiles (proportions of a gene in a chromatin state dominated by activating or repressive histone modifications) and accessibility remain largely unchanged during GATA1-induced erythroid differentiation. In contrast, gene induction and repression are strongly associated with changes in patterns of transcription factor occupancy. Our results indicate that during erythroid differentiation, the broad features of chromatin states are established at the stage of lineage commitment, largely independently of GATA1. These determine permissiveness for expression, with subsequent induction or repression mediated by distinctive combinations of transcription factors.

A varying threshold method for ChIP peak-calling using multiple sources of information

Motivation: Gene regulation commonly involves interaction among DNA, proteins and biochemical conditions. Using chromatin immunoprecipitation (ChIP) technologies, protein–DNA interactions are routinely detected in the genome scale. Computational methods that detect weak protein-binding signals and simultaneously maintain a high specificity yet remain to be challenging. An attractive approach is to incorporate biologically relevant data, such as protein co-occupancy, to improve the power of protein-binding detection. We call the additional data related with the target protein binding as supporting tracks.

Results: We propose a novel but rigorous statistical method to identify protein occupancy in ChIP data using multiple supporting tracks (PASS2). We demonstrate that utilizing biologically related information can significantly increase the discovery of true protein-binding sites, while still maintaining a desired level of false positive calls. Applying the method to GATA1 restoration in mouse erythroid cell line, we detected many new GATA1-binding sites using GATA1 co-occupancy data.

Availability:http://stat.psu.edu/∼yuzhang/pass2.tar

Contact:yuzhang@stat.psu.edu

Erythroid GATA1 function revealed by genome-wide analysis of transcription factor occupancy, histone modifications, and mRNA expression

The transcription factor GATA1 regulates an extensive program of gene activation and repression during erythroid development. However, the associated mechanisms, including the contributions of distal versus proximal cis-regulatory modules, co-occupancy with other transcription factors, and the effects of histone modifications, are poorly understood. We studied these problems genome-wide in a Gata1 knockout erythroblast cell line that undergoes GATA1-dependent terminal maturation, identifying 2616 GATA1-responsive genes and 15,360 GATA1-occupied DNA segments after restoration of GATA1. Virtually all occupied DNA segments have high levels of H3K4 monomethylation and low levels of H3K27me3 around the canonical GATA binding motif, regardless of whether the nearby gene is induced or repressed. Induced genes tend to be bound by GATA1 close to the transcription start site (most frequently in the first intron), have multiple GATA1-occupied segments that are also bound by TAL1, and show evolutionary constraint on the GATA1-binding site motif. In contrast, repressed genes are further away from GATA1-occupied segments, and a subset shows reduced TAL1 occupancy and increased H3K27me3 at the transcription start site. Our data expand the repertoire of GATA1 action in erythropoiesis by defining a new cohort of target genes and determining the spatial distribution of cis-regulatory modules throughout the genome. In addition, we begin to establish functional criteria and mechanisms that distinguish GATA1 activation from repression at specific target genes. More broadly, these studies illustrate how a "master regulator" transcription factor coordinates tissue differentiation through a panoply of DNA and protein interactions.

Arsenite-induced cytotoxicity in dorsal root ganglion explants

Peripheral neuropathy is common in people chronically overexposed to arsenic. We studied sodium arsenite (arsenite)-induced cytotoxicity in dorsal root ganglion (DRG) explants. Incubation with arsenite concentration- and time-dependently increased the expression of stress proteins, heat shock protein 70, and heme oxygenase-1 in DRG explants. Furthermore, apoptosis was involved in the arsenite-induced cytotoxicity in the treated DRG. Elevation in cytosolic cytochrome c levels and reduction in procaspase 3 levels suggested an involvement of the mitochondrial pathway in arsenite-induced apoptosis in this preparation. At the same time, increases in the activating transcription factor-4 and C/EBP homologous protein and reduction in procaspase 12 levels indicated activation of the endoplasmic reticulum (ER) pathway in the arsenite-induced cytotoxicity in DRG explants. Salubrinal (30 microM), an ER inhibitor, was found to attenuate arsenite-induced DNA fragmentation and reduction in procaspase 12 in DRG explants. Cytotoxic effects by arsenite, sodium arsenate (arsenate), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) were compared, and the potency was as follows: arsenite >>> arsenate>MMA and DMA. Recombinant adenovirus vectors encoding glial-cell-derived neurotrophic factor (AdGDNF) genes allowed a stable delivery of GDNF genes to the infected cells in DRG explants. Applied in this manner, AdGDNF was found to inhibit arsenite-induced DNA fragmentation in DRG explants. Moreover, AdGDNF attenuated the arsenite-induced reduction in procaspases 3 and 12 levels. Taken together, our study demonstrates that arsenite is capable of inducing cytotoxicity in DRG explants. Both ER and mitochondria pathways are involved in the arsenite-induced apoptosis in DRG explants. Glial-cell-derived neurotrophic factor appears to be protective against arsenite-induced peripheral neuropathy.

Antioxidative effect of vitamin D3 on zinc-induced oxidative stress in CNS

Antioxidative mechanisms of vitamin D3 were evaluated both in vitro and in vivo. A 4-h incubation of brain homogenates at 37 degrees C increased the formation of Schiff base fluorescent products of malonaldehyde, an indicator of lipid peroxidation. Incubation with vitamin D3 dose-dependently suppressed auto-oxidation. The antioxidative potency for inhibiting zinc-induced lipid peroxidation was as follows: vitamin D3 > Trolox (a water-soluble analogue of vitamin E) > or = beta-estradiol > melatonin. In the presence of high dose of desferrioxamine, a metal chelator, vitamin D3 attenuated auto-oxidation. These in vitro data indicate that vitamin D3 may act as a terminator of the lipid peroxidation chain reaction. The antioxidative effect of vitamin D3 on zinc-induced oxidative injury was verified using local infusion of vitamin D3 in vivo. Intranigral infusion of zinc elevated lipid peroxidation in the infused substantia nigra and depleted striatal dopamine content at 7 days after infusion. Furthermore, elevated cytosolic cytochrome c and DNA ladder, indicatives of apoptosis, were demonstrated in the infused substantia nigra. Simultaneous infusion of vitamin D3 and zinc prevented oxidative injury and apoptosis induced by zinc alone. The involvement of glia-derived neurotrophic factor (GDNF) expression was excluded since vitamin D3 did not alter GDNF level in the infused substantia nigra at 24 h or 4 days after intranigral infusion of vitamin D3. Our results suggest that vitamin D3, independent of upregulation of GDNF expression, may acutely prevent zinc-induced oxidative injuries via antioxidative mechanisms.

Clinical experience of percutaneous femoral venous catheterization in critically ill preterm infants less than 1,000 grams

BACKGROUND

Venous access is relatively difficult in preterm infants. Central venous catheterization is indicated for pressure monitoring, drug therapy, and nutrition supplementation, which are often critical in the anesthetic management of infants undergoing major surgery.

METHODS

In 49 critically ill preterm infants weighing less than 1,000 g, the femoral vein was cannulated using a 22-gauge Angiocath (25 mm; Beckton Dickinson, Sandy, UT). A 2.5-ml syringe was attached to the Angiocath, and the Angiocath was advanced with constant negative pressure over the syringe. When blood return was observed, the cannula was advanced. When free blood reflux was achieved, a J wire was inserted, followed by a 24-gauge central venous catheter.

RESULTS

The overall catheterization success rate was 79.6% (39 of 49 attempts). The time required for successful catheterization was less than 10 min in 18 cases (46.2%), 10-20 min in 17 cases (43.6%), and 20-30 min in 4 cases (10.3%). In the successful group, 1 catheter tip was positioned in the vein of the liver (2.6%), 2 were in the common iliac vein (5.1%), 6 were in the right atrium (15.4%), and 30 were in the infracardiac inferior vena cava (76.9%). Complications included hematoma in six cases (12.2%), arterial puncture in five cases (10.2%), bleeding in two cases (4.1%), and transient bradycardia in two cases (4.1%).

CONCLUSIONS

The results indicate that percutaneous femoral venous catheterization is a reliable and valuable technique for critically ill preterm infants weighing less than 1,000 g.

The anesthetic management of a preterm infant weighing 500 grams undergoing ligation of patent ductus arteriosus--a case report

PDA (patent ductus arteriosus) is a common congenital heart disease. Usually surgical intervention through left thoracotomy or recently through video assisted thoracoscopy will be recommended if the preceding or intent medical treatment fails or is contraindicated. However, once surgical intervention is decided, various complications are still a real fear in the mind of the surgeon and the anesthesiologist, particularly if the infant is premature or very sick. Here we report an anesthetic management in a female preterm infant weighing 500 grams, who underwent PDA ligation. She was born at gestation age of 28 weeks at our hospital, and since her birth she was noted to have infant respiratory distress syndrome associated with renal dysfunction. She was admitted to the neonatal intensive care unit (NICU) straightaway. After thorough examination, a severe PDA was disclosed. The possibility of pulmonary hemorrhage and heart failure could be predicted in view of the large left to right shunt. Worst of all was that her poor renal function contradicted a medical treatment. So we decided to carry out the ligation procedure at once although she was premature and only 5 days old. The NICU was chosen as the operation theater for transferring concerns. General anesthesia was induced and maintained by atropine 0.01 mg, pancuronium 0.1 mg, fentanyl 2 micrograms, and ketamine 0.15 mg intravenously. Supplemental oxygen was given throughout the operation. The PDA was ligated through left thoracotomy and blood loss was minimal. The peri-operative course was uneventful. The patient recovered well following surgery and anesthesia.

A feasibility study of the in vivo prompt gamma activation analysis using a mobile nuclear reactor

A facility for in vivo prompt gamma activation analysis using moderated neutron beams from a 0.1 W mobile nuclear reactor is described. The low-power nuclear reactor provides total neutron flux of 3.3 X 10(4)n cm-2 s-1 on the surface of a vertical beam tube to which a liquid phantom is positioned. The capability of such a partial-body irradiation facility is demonstrated by measuring trace amounts of toxic cadmium in kidney. The detection limit of Cd in kidney for a skin dose of 1.66 mSv (166 mrem) is 1.34 mg under 500 s irradiation. This facility therefore combines the advantages of mobility with high sensitivity of detection of a toxic element under low neutron and gamma doses.