The Repeatability of Pharyngeal Opening Pressure Under Drug-Induced Sleep Endoscopy

OBJECTIVE

Pharyngeal opening pressure (PhOP) is a measure of upper airway collapsibility that can be obtained during drug-induced sleep endoscopy (DISE) using a continuous positive airway pressure (CPAP) titration. However, the stability of PhOP over the course of sedation during DISE remains unclear. This study aims to compare repeat measures of PhOP over the course of DISE.

STUDY DESIGN

Single arm prospective study.

SETTING

Single tertiary care institution.

METHODS

Patients had 2 CPAP titrations while undergoing DISE. Collected data included patient demographics, PhOP, patient sedation index (PSI), and duration of and between CPAP titrations. t Tests, test-retest coefficient analysis, and repeated measures correlation were performed.

RESULTS

Twenty-five patients completed the study between 2022 and 2023 with 22 patients having sedation depth (PSI) recording. Most were male (76%), obese (average body mass index: 30.24 kg/m2), with severe obstructive sleep apnea (average apnea-hypopnea index: 39.8 events/hr). Test-retest analysis showed good-excellent correlation between PhOP values (intraclass correlation coefficient = 0.892, P < .0001, n = 25). Average time between CPAP titrations was 15 minutes to 6 seconds. Over that time, PhOP increased by an average of 0.72 cmH2O (P = .06, n = 25) and PSI decreased by 9.5 units (P = .01, n = 22). Repeated measures correlation showed a weak negative correlation between PhOP and PSI (r = -.45, P = .03, n = 22).

CONCLUSION

The results showed repeatability of PhOP values over the course of DISE. When adjusted for sedation depth (PSI), deeper sedation was weakly associated with greater PHOP. However, the magnitude of this change was small and we conclude that PhOP remains relatively stable over the course of DISE (Effects of Lung Volume on Upper Airway Patency During DISE [DISE-Pulm], NCT05350332, clinicaltrials.gov).

Posterior Palatal Expansion via Subnasal Endoscopy (2PENN) for Maxillary Deficiency: A Pilot Study

OBJECTIVE

Surgically assisted rapid palatal expansion (SARPE) addresses transverse maxillary deficiency, a known contributor to nasal obstruction. The purpose of this study was to assess the feasibility, preliminary outcomes, and safety of posterior palatal expansion via subnasal endoscopy (2PENN), a modified SARPE procedure, aimed at achieving anterior and posterior maxillary expansion.

METHODS

This prospective case series included consecutive adult patients with findings of transverse maxillary deficiency that underwent the 2PENN procedure from 4/2021 to 4/2022. Patients completed pre- and post-operative clinical evaluations, Nasal Obstruction and Septoplasty Effectiveness (NOSE) questionnaires, and computed tomography (CT), with measures including expansion at the level of the posterior nasal spine (PNS), first maxillary inter-molar distance (IMD), and anterior nasal spine (ANS).

RESULTS

The cohort (N = 20) was middle-aged (39 ± 11 years), predominantly male (80%), and overweight (BMI 28 ± 4 kg/m2 ). The majority (85%) of patients had sleep breathing issues, of which 10 (59%) had polysomnography-confirmed obstructive sleep apnea (OSA). Full anterior-posterior separation of the mid-palatal suture line was evident on all post-operative CT scans, with mean expansion at the PNS of 3.6 ± 1.3 mm, IMD of 6.1 ± 1.6 mm and ANS of 7.0 ± 1.6 mm (p < 0.001). Following surgery, mean NOSE scores improved from 57 ± 23 to 14 ± 13 (p < 0.001). One patient required maxillary antrostomy for post-operative sinusitis.

CONCLUSION

2PENN is an effective and safe technique for achieving both anterior and posterior maxillary expansion in patients with transverse maxillary deficiency. Further study is warranted to better understand the effect of 2PENN in patients with OSA, particularly as it relates to improving pharyngeal patency.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:1970-1977, 2024.

[Epidemiological characteristics and analysis of related infection risk factors for influenza in Anhui Province from 2013 to 2021]

Objective: Analysis of the characteristics of influenza epidemic in Anhui Province and quantification of the impact of different factors on influenza occurrence, providing scientific basis for better influenza prevention and control. Methods: Descriptive analysis and factor analysis were conducted on influenza-like illness (ILI) cases and RT-PCR results in Anhui Province from 2013 to 2021 using data from China's Influenza Monitoring Information System. Results: The percentage of influenza-like illness (ILI%) of sentinel hospitals in Anhui Province from April 1, 2013 to March 31, 2021 was 3.80% (1 209 142/31 779 987), showing an overall increasing trend, with a relatively high proportion in 2017-2018 at 4.30% (191 148/4 448 211). The proportion of ILI cases in infants and young children aged 0-4 years was a relatively high at 54.14% (654 676/1 209 142), and the highest ILI% was observed in Fuyang City, Anhui Province (6.25%, 236 863/3 788 863). Laboratory monitoring results showed that the positive rate of ILI cases in sentinel hospitals in 8 influenza monitoring years was 16.38% (34 868/212 912), showing an increasing trend year by year, with a relatively proportion in 2017-2018 at 26.19% (6 936/26 488). The detection rate of school-age children aged 5-14 years was a relativelyhigh at 28.81% (13 869/48 144), and the positive rate was a relatively high in Wuhu City among the 16 cities, reaching 22.01% (2 693/122 237). Influenza activity showed a single peak in winter-spring and alternating double peaks in winter-spring and summer, with different subtypes alternating, and A (H3N2) was the dominant subtype in summer. The results of a multiple logistic regression model showed that the positive rate was higher in 2017-2018, among children aged 5-14 years, in winter, and in southern Anhui. Conclusions: Influenza epidemic in Anhui Province has a clear seasonal pattern, and the ILI% and detection rate have shown an upward trend from 2013 to 2021. Therefore, it is suggested to ensure vaccine supply before the winter-spring influenza season arrives, and to strengthen vaccine uptake and health education to avoid the risk of infection during the peak period of influenza.

International Consensus Statement on Obstructive Sleep Apnea

BACKGROUND

Evaluation and interpretation of the literature on obstructive sleep apnea (OSA) allows for consolidation and determination of the key factors important for clinical management of the adult OSA patient. Toward this goal, an international collaborative of multidisciplinary experts in sleep apnea evaluation and treatment have produced the International Consensus statement on Obstructive Sleep Apnea (ICS:OSA).

METHODS

Using previously defined methodology, focal topics in OSA were assigned as literature review (LR), evidence-based review (EBR), or evidence-based review with recommendations (EBR-R) formats. Each topic incorporated the available and relevant evidence which was summarized and graded on study quality. Each topic and section underwent iterative review and the ICS:OSA was created and reviewed by all authors for consensus.

RESULTS

The ICS:OSA addresses OSA syndrome definitions, pathophysiology, epidemiology, risk factors for disease, screening methods, diagnostic testing types, multiple treatment modalities, and effects of OSA treatment on multiple OSA-associated comorbidities. Specific focus on outcomes with positive airway pressure (PAP) and surgical treatments were evaluated.

CONCLUSION

This review of the literature consolidates the available knowledge and identifies the limitations of the current evidence on OSA. This effort aims to create a resource for OSA evidence-based practice and identify future research needs. Knowledge gaps and research opportunities include improving the metrics of OSA disease, determining the optimal OSA screening paradigms, developing strategies for PAP adherence and longitudinal care, enhancing selection of PAP alternatives and surgery, understanding health risk outcomes, and translating evidence into individualized approaches to therapy.

The Accuracy and Reliability of Visually Assessed Pharyngeal Opening Pressures During Drug-Induced Sleep Endoscopy

OBJECTIVE

To examine the accuracy and interrater reliability of a visually assessed vs airflow-based measure of pharyngeal collapsibility obtained in patients with obstructive sleep apnea undergoing drug-induced sleep endoscopy (DISE).

STUDY DESIGN

Prospective observational study.

SETTING

Academic tertiary care practice.

METHODS

Patients underwent DISE with airflow monitoring and nasal positive airway pressure titration to determine visual and airflow-based levels of pharyngeal opening pressure (PhOP). Visual DISE-PhOP was assessed by 2 blinded independent raters and defined as the pressure at which visual confirmation of airway collapse, including snoring, was abolished. Airflow-based DISE-PhOP was defined as the minimally effective positive airway pressure that abolished inspiratory flow limitation. Equivalence testing between visual and airflow DISE-PhOP of each rater was performed with the two one sided T-test (TOST) with an a priori equivalence bound of ±1 cm H2 O. Interrater reliability was evaluated with the intraclass correlation coefficient.

RESULTS

One hundred patients were enrolled in the study and 77 completed the full evaluation. The population was predominantly male (74%) with an average age of 54.8 years, body mass index of 30.1 kg/m2 , and apnea-hypopnea index of 30.7 events/h. Equivalence testing showed that both raters were within ±1 cm H2 O of airflow-based DISE-PhOP (-0.43 to 0.09 cm H2 O and -0.32 to 0.48 cm H2 O). Interrater reliability of visual DISE-PhOP between the raters was also good to excellent with an intraclass correlation coefficient of 0.895 (95% CI, 0.84-0.932).

CONCLUSION

DISE-PhOP, a measure of upper airway collapsibility, was equivalent between airflow-based and visual assessments with strong interrater reliability, supporting its adoption as a standardized objective parameter in clinical DISE.

[A two-stitch continuous suture method for single-lumen ileostomy]

Objective: To explore the value of a two-stitch continuous suture in single- lumen ileostomy. Methods: This was a retrospective cohort study. Data for 98 patients who underwent single-lumen enterostomy were retrospectively collected between 1 January 2021 and 1 May 2022 at Zhujiang Hospital of Southern Medical University. All patients met the indications for prophylactic single-lumen ileostomy. Those older than 80 years of age, with complex underlying diseases, extremely poor systemic conditions who could not tolerate surgery, poor blood supply at the end of the bowel, and severe edema or severe infection at the end of the bowel were excluded. Among the included patients, patients who underwent surgery before 1 October 2021 underwent ileostomy with interrupted suture (control group, n=60), and patients operated on and after 1 October 2021 routinely underwent two-stitch continuous suture ileostomy (two-stitch stoma group, n=38). Two-stitch continuous suture ileostomy is performed as follows: the first continuous suture is used to suture the intestinal seromuscular layer, peritoneum, posterior sheath, and anterior sheath from deep to superficial layers. The bowel wall is then opened. The second continuous suture is used to suture the full thickness of the bowel and the skin. The differences in postoperative ostomy-related complications and operation time were compared between the groups. Results: There were no significant differences in baseline data between the groups (all, P>0.05). The operative time in the two-stitch stoma group was shorter than that of the control group (16.6±2.2 minutes vs. 25.1±2.4 minutes, respectively; t=-17.874;P<0.001). The incidences of mucocutaneous separation, dermatitis, and stoma rebound in the two-stitch stoma group were lower than those of the control group [5.3% (2/38) vs. 31.7% (19/60), χ²=9.633, P=0.002;5.3% (2/38) vs. 28.3% (17/60), χ²=7.923, P=0.005; and 2.6% (1/38) vs. 18.3% (11/60), P=0.026, respectively], while the incidences of parastomal hernia and stoma prolapse, and the postoperative visual analog scale scores in the two groups were similar (all P>0.05). Conclusion: Compared with traditional single-lumen ileostomy, two-stitch continuous suture ileostomy has the advantages of short operation time, simplicity, esthetic appearance of the stoma, and a significant reduction in the postoperative complications associated with ileostomy.

The role of craniofacial maldevelopment in the modern OSA epidemic: a scoping review

STUDY OBJECTIVES

There is increasing recognition that environmental factors affect human craniofacial development and our risk for disease. A scoping review of the literature was performed looking at environmental influences on craniofacial development to better understand this relationship and investigate what further study is needed to determine how this relationship may impact obstructive sleep apnea.

METHODS

A comprehensive literature search was performed using the Ovid Medline database from inception to May, 2020 with relevance to craniofacial development in 5 clinically-oriented variables: diet, secular change, breastfeeding/non-nutritive sucking habits (NNSH), nasal obstruction/mouth breathing, and masticatory muscle function. The Oxford Centre for Evidence-Based Medicine Levels of Evidence (LoE) was used to assess studies based on study design.

RESULTS

18,196 articles were initially identified, of which 260 studies were fully reviewed and 97 articles excluded. The remaining 163 articles were categorized as follows: Secular change (n = 16), Diet (n = 33), Breastfeeding/NNSH (n = 28), Nasal obstruction/Mouth breathing (n = 57), and Masticatory muscle function (n = 35). 93% of included studies reported a significant association between craniofacial morphology and environmental factors. The majority of studies were characterized as low LoE studies with 90% of studies being LoE 4 or 5.

CONCLUSIONS

The studies in this review suggest that environmental factors are associated with changes in craniofacial development. However, most studies were heterogeneous and low-level studies, making strong conclusions about these relationships difficult. Future rigorous studies are needed to further our understanding of environmental influences on craniofacial development and OSA risk.

A comparison of ultrasound echo intensity to magnetic resonance imaging as a metric for tongue fat evaluation

STUDY OBJECTIVES

Tongue fat is associated with obstructive sleep apnea (OSA). Magnetic resonance imaging (MRI) is the standard for quantifying tongue fat. Ultrasound echo intensity has been shown to correlate to the fat content in skeletal muscles but has yet to be studied in the tongue. The objective of this study is to evaluate the relationship between ultrasound echo intensity and tongue fat.

METHODS

Ultrasound coronal cross-sections of ex-vivo cow tongues were recorded at baseline and following three 1 mL serial injections of fat into the tongue. In humans, adults with and without OSA had submental ultrasound coronal cross-sections of their posterior tongue. The average echo intensity of the tongues (cow/human) was calculated in ImageJ software. Head and neck MRIs were obtained on human subjects to quantify tongue fat volume. Echo intensity was compared to injected fat volume or MRI-derived tongue fat percentage.

RESULTS

Echo intensity in cow tongues showed a positive correlation to injected fat volume (rho = 0.93, p < .001). In human subjects, echo intensity of the tongue base strongly correlated with MRI-calculated fat percentage for both the posterior tongue (rho = 0.95, p < .001) and entire tongue (rho = 0.62, p < .001). Larger tongue fat percentages (rho = 0.38, p = .001) and higher echo intensity (rho = 0.27, p = .024) were associated with more severe apnea-hypopnea index, adjusted for age, body mass index, sex, and race.

CONCLUSIONS

Ultrasound echo intensity is a viable surrogate measure for tongue fat volume and may provide a convenient modality to characterize tongue fat in OSA.

[Genotyping analysis of norovirus infectious diarrhea clusters in Songjiang district, Shanghai from 2017 to 2019]

Objective: We aimed to analyze the the genotyping of norovirus infectious diarrhea epidemic in Songjiang district, Shanghai, and explored the experience in handling the epidemic to provide a scientific basis for formulating prevention and treatment strategies. Methods: The epidemiological data and related samples of 69 outbreaks of infectious diarrhea caused by norovirus was collected from 2017 to 2019 in Songjiang district, Shanghai. Sequencing and type identification were performed by the method of gene sequencing for the junction region of Norovirus ORF1 and ORF2. Results: From 2017 to 2019, 69 outbreaks of norovirus infections diarrhea were reported in Songjiang district, Shanghai. A total of 1 767 samples were tested, including 619 case samples (positive rate 19.9%), 343 practitioner samples (positive rate 1.1%), 505 environmental samples (positive rate 0.5%) and 300 food samples (not detected). 141 sequences were obtained, and the genotype analysis showed that the genotype that mainly caused infectious diarrhea in 2017 and 2018 was GII.P16-GII.2 (50.98%, 26/51). In 2019, the genotypes that mainly caused infectious diarrhea were GII.P16-GII.2 (13.73%, 7/51) and GII.Pe-GII.4 (9.80%, 5/51). Conclusion: The main genotype of the 69 outbreaks of nororirus infectious diarrhea epidemic in Songjiang district, Shanghai from 2017 to 2019 was GII.P16-GII.2, which showed obvious peaks in spring, autumn and winter. There were more infections in kindergartens and schools. The surveillance of norovirus infection should be strengthened.

Influence of apnea vs hypopnea predominance in predicting mean therapeutic positive airway pressures among patients with obstructive sleep apnea

STUDY OBJECTIVES

Lower therapeutic positive airway pressure (PAP) levels are associated with improved response to non-PAP therapies in the treatment of obstructive sleep apnea. The aim of this study was to evaluate the prevailing notion that patients with apnea-predominant obstructive sleep apnea require higher therapeutic PAP levels compared to patients with hypopnea-predominant obstructive sleep apnea.

METHODS

An institutional review board-approved retrospective review was performed using strict inclusion criteria: presence of type I or III sleep study, apnea-hypopnea index > 10 events/h, and adherence to auto-adjusting continuous positive airway pressure. Patients were stratified by apnea (> 50% apneas) or hypopnea (≤ 50% apneas) predominance, and PAP data were compared. Statistical analyses were performed using Student's t test and linear regression modeling.

RESULTS

Between January 1, 2018 and January 1, 2020, 500 patients met inclusion criteria. Two hundred twenty-one (44.1%) patients were apnea-predominant and 279 (55.8%) were hypopnea-predominant. Apnea-predominant patients had a slightly greater mean PAP (9.01 vs 8.36, P = .002) than hypopnea-predominant patients. Univariable and multivariable linear regression of 7 variables (obstructive apnea percentage, age, sex, body mass index, apnea-hypopnea index, O₂ nadir, mask type) showed obstructive apnea percentage was the weakest predictor of therapeutic PAP levels.

CONCLUSIONS

Apnea-predominant individuals demonstrated a clinically insignificant difference in PAP level compared to hypopnea-predominant individuals; moreover, obstructive apnea percentage was not a strong predictor of therapeutic PAP levels. Of the modeled variables, the strongest predictor of PAP level was apnea-hypopnea index. Further studies are needed to explore these relationships as well as additional variables that may contribute to predicting therapeutic PAP levels.

CITATION

Yu JL, Liu Y, Tangutur A, et al. Influence of apnea vs hypopnea predominance in predicting mean therapeutic positive airway pressures among patients with obstructive sleep apnea. J Clin Sleep Med. 2021;17(11):2171-2178.

Relation between arousability and outcome of upper airway stimulation in the Stimulation for Apnea Reduction (STAR) Trial

STUDY OBJECTIVES

Upper airway stimulation (UAS) is an innovative surgical treatment for obstructive sleep apnea; however, the treatment failure rate is approximately 22%. Easy arousability may limit the tolerability of stimulation and, by extension, its effectiveness. The odds ratio product (ORP) is a continuous electroencephalographic metric of arousal propensity (range: 0 [deep sleep] to 2.5 [full wakefulness]), and its rate of decline after arousal (ORP-9) is a risk factor for susceptibility to arousal in the presence of frequent arousal stimuli. We hypothesized that individuals with deeper sleep (low average ORP and low ORP-9) are more likely to respond to UAS.

METHODS

ORP and ORP-9 were calculated from 126 baseline polysomnograms of participants in the STAR Trial. These values were compared between responders and nonresponders. Adjusted linear modeling was performed to determine the association between ORP-derived variables and treatment response.

RESULTS

No differences were found between responders and nonresponders in unadjusted comparisons of ORP-derived variables. On linear regression modeling, significant correlation was found between non-rapid eye movement ORP and reduction in apnea-hypopnea index (P = .004).

CONCLUSIONS

No significant difference in ORP was noted between responders and nonresponders to UAS therapy; however, contrary to our initial hypothesis, linear regression modeling trended toward a positive relationship between ORP and UAS response, suggesting that those who have lighter sleep are more likely to respond to therapy; however, these results are only exploratory, and future larger prospective studies are needed to confirm this relationship.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: STAR Trial; Identifier: NCT01161420.

[Clinical study on early loading restoration of superhydrophilic implants]

Objective: To study the clinical effect of early loading restoration a superhydrophilic implant after 1 year, so as to provide reference evidence for clinical practice. Methods: A total of 41 patients with dental defects, including 20 males and 21 females [age (52.3±13.1) years old], were enrolled in the Department of VIP, Hangzhou Dental Hospital (Pinghai Hospital) from July 2017 to January 2019. A total of 74 superhydrophilic implants were implanted, including 27 maxillary implants and 47 mandiolar implants. All patients without bone augmentation or soft tissue transplantation, the maxilla was taken impression 4 weeks after implant implantation, with 6 weeks of loading, the mandible was taken impression 2 weeks after implant implantation, with 4 weeks of loading. The stability of the implant was measured by resonance frequency analyzer before implant implantation, impression and loading. Periapical radiograph were taken immediately after mold removal, immediately after loading and reexamination 1 year after loading, to measure and record the changes in the bone level of the mesial and distal margins of the implant. Results: No biological complications occurred in all implants before loading restoration, and the implant survival rate was 100%(74/74). In 2 cases, the implant stability quotient (ISQ) value of the implant at the mandibular site was lower than 65 at 2 weeks after surgery, and the restoration was delayed. The ISQ values of the other 72 implants at the time of implantation (75.22±4.32) were not significantly different from those at the time of modeling (75.13±4.23) (P>0.05), but the ISQ values at the moment of weight loading (76.46±3.73) were significantly higher than those at modeling (P<0.05). All the early loading implants were reviewed 1 year after early loading, and none of them were loose or fell off, and the implant survival rate was 100%(72/72). X-ray measurement and evaluation showed that after 1 year of early loading restoration, the mean marginal bone absorption of 72 implants was (0.18±0.06) mm, among which the mandibular was (0.17±0.06) mm and the maxillary was (0.19±0.06) mm, showing no statistical difference (P>0.05). After 1 year of early loading restoration, the mean marginal bone absorption of 72 implants was (0.17±0.05) mm, including (0.17±0.06) mm for mandibular and (0.16±0.05) mm for maxillary, showing no statistical difference (P>0.05). Conclusions: In the limited scope of this clinical study, it has been proved that early loading of superhydrophilic implant is a safe and feasible treatment scheme, and the bone resorption at the implant edge after long-term early loading restoration needs further follow-up study.

Prospective Determination of Airway Response to Upper Airway Stimulation: A New Opportunity for Advanced Device Titration

OBJECTIVES/HYPOTHESIS

Response to upper airway stimulation (UAS) is associated with the degree of airway opening during stimulation. UAS programming may affect this opening. The objective of this study was to examine airway changes in response to five different electrode configurations programmable within the Inspire UAS system.

STUDY DESIGN

Prospective single-arm cohort study.

METHODS

Subjects who underwent UAS implantation were recruited for a prospective single-arm cohort study during UAS device activation. Functional thresholds were recorded for all settings. Awake nasopharyngoscopy was performed to examine the retropalatal (RP) and retroglossal (RG) regions at rest and during activation with all settings at their functional thresholds. Cross-sectional measurements were made by two blinded reviewers and reported as percent change in airway size.

RESULTS

Sixteen patients were included. The standard setting (+-+) resulted in the greatest change in RP area in 43.8% of patients. An alternative setting resulted in greatest change in 56.2% of patients (--- and o-o in 18.8% each, -o- in 12.5%, and -+- in 6.3% of patients). Average response to all five settings was utilized to classify degree of palatoglossal coupling. Most patients had some enlargement (20%-70% change in RP area, 43.8%) or no enlargement (<20% change, 43.8%), whereas a minority of patients (12.5%) had marked enlargement (>70% change). RP and RG expansion were not correlated.

CONCLUSION

Degree of RP expansion varied among patients and settings. Although the standard setting resulted in greatest RP change in a plurality of patients, over half had a greater response to an alternative setting. Future studies should address whether choice of setting based on RP expansion results in improved outcomes.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:218-223, 2021.

0691 Comparison Of Odds Ratio Product And Other Polysomnographic Metrics Among Responders And Non-responders To Upper Airway Stimulation Treatment Of Obstructive Sleep Apnea

Introduction

Upper airway stimulation (UAS) is a surgical method of treating obstructive sleep apnea (OSA). UAS involves an implantable neuro-stimulator that stimulates the hypoglossal nerve to protrude the tongue during sleep. OSA fails to improve in 22% of patients who receive UAS as defined by a &gt; 50% reduction in Apnea-Hypopnea Index (AHI) and an AHI &lt;20 events/hour. Light sleep may predict UAS failure in that it may limit the stimulus strength that can be applied. The odds ratio product (ORP) is a novel polysomnographic (PSG) metric of sleep depth. We hypothesized that ORP values prior to surgery will be higher (lighter sleep) in non-responders. Having markers that predict surgical success can help reduce unnecessary surgeries.

Methods

This is a retrospective cohort study of 126 patients (83 responders vs. 43 non-responders) who received UAS implantation for the treatment of OSA. PSG data was obtained from the Stimulation for Apnea Reduction (STAR) trial. Raw baseline PSG data were analyzed and ORP values calculated using Michele Sleep Scoring Software (Cerebra Medical, Winnipeg, CA). In addition, 13 PSG metrics that were considered possibly relevant to surgical outcome were calculated as an exploratory analysis. The measurements included: spindle density, spindle power, spindle frequency, alpha intrusion, Right/Left sleep depth correlation coefficient, respiratory duty cycle, respiratory flow limitation, and arousal intensity. Statistical Analysis: Comparisons between responders and non-responders used parametric t-tests for continuous data and chi-squared or Fisher’s exact tests for categorical data. Statistical significance was based on a Bonferroni-corrected p&lt;0.00357.

Results

Differences in ORP values and other PSG metrics between responders and non-responders were not statistically significant. Of all PSG metrics only differences in spindle density approached statistical significance (Responders = 2.33 spindles/minute vs Non-Responders = 1.39 spindles/minute, p=0.00360).

Conclusion

The findings suggest that differences in sleep depth and several other sleep characteristics do not play a significant role in determining response to UAS therapy.

Support

This project was supported by a Sleep Research Society Career Development Award #023-JP-19

Utility of the modified Mallampati grade and Friedman tongue position in the assessment of obstructive sleep apnea

STUDY OBJECTIVES

The modified Mallampati (MM) grade and Friedman tongue position (FTP) are commonly used scales that assess the oropharynx during evaluation for obstructive sleep apnea (OSA). Though used by many practitioners, there is controversy in the literature regarding their practical utility. The goal of this review will be to review the history of how the MM and FTP were developed, to discuss current evidence for their usefulness in the workup of OSA, and to provide future direction to better understand their utility in the workup of OSA.

METHODS

We searched the literature (PubMed) for the terms "modified Mallampati" and "Friedman tongue position." Articles were selected based on our study objectives emphasizing articles discussing the utility of MM and FTP in managing OSA.

CONCLUSIONS

MM and FTP have the potential to be useful assessment tools in the evaluation of OSA. When performing this examination, it is important for physicians and other medical providers to understand the pitfalls of the MM and FTP including the potential difficulty in performing the exam and the lack of consistency between examiners in both the terminology and execution of this physical exam finding. Better methods to standardize the assessment are necessary to ensure consistent evaluation among individual examiners while at the same time keeping the method simple and convenient for wide use as a clinical screening tool.

Updates on management of pediatric obstructive sleep apnea

Obstructive sleep apnea (OSA) affects about 1%-5% of the pediatric population. The consequences of untreated OSA in children include neurocognitive deficits, behavioral problems, poor school performance as well as systemic and pulmonary hypertension. The treatment options for pediatric OSA are numerous with a variety of surgical and non-surgical interventions. As our understanding of the complexities of OSA grows, the options for management have continued to expand as well. The objectives of this review are to describe the commonly prescribed treatments for pediatric OSA including adenotonsillectomy as well as use of positive airway pressure. We also highlight other surgical and non-surgical interventions available. In addition, we provide updates on current research focusing on newer diagnostic and experimental treatment modalities.

Temperature and excitation wavelength dependence of circular and linear photogalvanic effect in a three dimensional topological insulator Bi2Se3

The circular (CPGE) and linear photogalvanic effect (LPGE) of a three-dimensional topological insulator Bi₂Se₃ thin film of seven quintuple layers excited by near-infrared (1064 nm) and mid-infrared (10.6 [Formula: see text]m) radiations have been investigated. The comparison of the CPGE current measured parallel and perpendicular to the incident plane, together with the comparison of the CPGE current under front and back illuminations, indicates that the CPGE under front illumination of 1064 nm light is dominated by the top surface states of the Bi₂Se₃ thin film. The CPGE current excited by 10.6 [Formula: see text]m light is about one order larger than that excited by 1064 nm light, which may be attributed to the smaller cancelation effect of the CPGE generated in the two-dimensional electron gas when excited by 10.6 [Formula: see text]m light. Under the excitation of 1064 nm light, the LPGE current is dominated by the component which shows an even parity of incident angles, while the LPGE current excited by 10.6 [Formula: see text]m light is mainly contributed by the component which is an odd parity of incident angles. Both of the CPGE and LPGE currents excited by 1064 nm decrease with increasing temperature, which may be owing to the decrease of the momentum relaxation time and the stronger electron-electron scattering with increasing temperature, respectively.

Upper airway stimulation therapy and sleep architecture in patients with obstructive sleep apnea

OBJECTIVES/HYPOTHESIS

To quantify changes in sleep architecture before and after upper airway stimulation (UAS) therapy in patients with obstructive sleep apnea.

STUDY DESIGN

Retrospective chart review.

METHODS

This study was performed at a single-institution tertiary academic care center. Patients who responded successfully to UAS implantation were selected for this study. Preoperative and postoperative sleep studies were compared to determine sleep architecture changes. Primary outcomes included sleep architecture parameters such as N1, N2, N3, and rapid eye movement (REM) in addition to others. Secondary outcomes included body mass index.

RESULTS

Thirty-five patients met inclusion criteria for this study. There was significant improvement across several sleep architecture parameters. N1 sleep percent decreased from 16.7% ± 2.1% preoperatively to 10.1% ± 1.6% postoperatively (P = .023). Time spent in N2 increased from 148.0 ± 12.4 minutes to 185.5 ± 10.4 minutes (P = .030), whereas N3 increased from 21.9 ± 5.0 minutes to 57.0 ± 11.1 minutes (P = .013). No significant changes were observed in REM sleep. Arousal index decreased from 38.8 ± 4.0 to 30.3 ± 4.0 (P = .050).

CONCLUSIONS

There was significant improvement across several sleep architecture parameters among patients who responded successfully to UAS implantation.

LEVEL OF EVIDENCE

4 Laryngoscope, 130:1085-1089, 2020.

Transoral robotic surgery versus upper airway stimulation in select obstructive sleep apnea patients

OBJECTIVES

Transoral robotic surgery (TORS) has been used to treat obstructive sleep apnea (OSA) since 2009, with recent meta-analysis showing an average reduction of apnea-hypopnea index (AHI) from 44.3 to 17.0. In 2014, upper airway stimulation surgery (UAS) was approved for OSA treatment, with results showing an average AHI reduction from 32.0 to 15.3. Given there was a period when TORS was available and UAS was not, we looked at a subset of patients treated with TORS but who could have qualified for UAS and compared their outcomes to patients who received UAS.

METHODS

This is a retrospective chart review comparing TORS to UAS in treatment of OSA performed by a single surgeon between 2011 and 2016. Inclusion criteria were a body mass index less than 35 and AHI between 20 and 65 consistent with criteria for UAS implantation. Patients who received TORS and met the inclusion criteria had their preoperative drug-induced sleep endoscopy recordings re-evaluated. Patients with anteroposterior retropalatal collapse that would have qualified them for UAS had their outcomes compared to patients who received UAS.

RESULTS

Results between TORS and UAS showed an average AHI reduction of 12.7 and 33.3, respectively. Overall cure rate, defined as AHI < 5, was 10.0% and 70.3%, respectively.

CONCLUSION

Results of this study indicate that, when met with criteria for both TORS and UAS, patients receiving UAS had greater improvement in several objective measures of OSA. Studies like this may help direct future treatment algorithms for surgical management of OSA.

LEVEL OF EVIDENCE

4 Laryngoscope, 129:256-258, 2019.

[Analysis of clinical characteristics of necrotizing enterocolitis in term infants]

OBJECTIVE

To investigate the characteristics and outcomes of necrotizing enterocolitis (NEC) in Chinese term infants population.

METHODS

A national neonatal necrotizing enterocolitis network was established. Neonates as having necrotizing enterocolitis with gestation age ≥37 weeks were identified if they met the accepted diagnostic criterion during the study period from Jan 1(st) 2011 to Dec 31(st) 2011. The data of maternal and neonates' characteristics, the comorbidities, the clinical interventions prior to NEC, the clinical courses and radiology results, the medical and surgical treatment and the outcomes were collected. SPSS 19.0 software was used to do statistic analysis. Logistic-regression models were used to analyze the risk factors for death in infants with NEC, odds ratio (OR) and 95% confidence interval (CI) were calculated.

RESULTS

There were 231 067 newborn infants, 164 307 of them were term infants, admitted to 95 hospitals in main land China. There were 718 term infants were diagnosed as necrotizing enterocolitis with the incidence of 0.44%. There were 294 term infants cases identified as ≥stage 2 necrotizing enterocolitis for the analysis, including 193 cases of stage 2 and 101 cases of stage 3.The mean gestation age was (39.0±1.3) weeks, and the mean birth weight was(3 087.4±548.3)g. The percentage of small for gestation age was 20.4%. The onset age of NEC was 5 (2-11)d. The percentage of cases received breast milk feeding was 23.7%. The most common comorbidities were sepsis (9.5%, 28/294), asphyxia (9.5%, 28/294), pneumonia (7.8%, 23/294) and congenital megacolon (7.5%, 22/294). The bowel perforation rate was 13.9%. The rate of cases who received surgical treatment was 25.2%(76.6% small intestinal necrosis and 65.8% small intestinal perforation). The mortality rate was 28.9%(the mortality rate were 20.7% and 44.6% in stage 2 and stage 3 NEC, respectively). Noninvasive continuous positive airway pressure treatment for NEC (OR=5.278, 95% CI: 2.058-13.533, P<0.01) and NEC staging 3 (OR=3.156, 95% CI: 1.766-5.642, P<0.01) were statistically significantly associated with mortality of NEC.

CONCLUSIONS

The term infants with necrotizing enterocolitis usually have the underlying comorbidities. The breastmilk feeding rate is low. Necrotizing enterocolitis remains high mortality in term neonates in Chinese neonatal units. Noninvasive continuous positive airway pressure treatment for NEC is statistically significantly associated with mortality of NEC.

[Digital imaging fiber optic transillumination (DIFOTI) method for determining the depth of cavity]

OBJECTIVE

To analyze the accuracy of the digital imaging fiber optic transillumination (DIFOTI) on diagnosis of caries lesions depth using DIAGNOcam system.

METHODS

This experiment adopted self-matching design. Seventy-four extracted teeth (molar: sixty-six, premolar: eight) with one caries lesions in proximity which were not damaged in surface marginal ridge were selected. Dental calculus and dental stains were removed from the extracted teeth for standby application. A sign was marked in the middle of the occlusal surface edge at the side of decay. Then the teeth were fixed in the standard model of dentition and cavities were adjacent with the sound tooth surface. Sticky wax was applied to seal the level of 2 mm beyond cemento-enamel junction (CEJ) in the direction of occlusion and interproximal space to imitate gingival margin and gingival papilla. The standard models of dentition was seated in imitation head mold. The lesions depth degree was looked into and checked with DIAGNOcam system. Besides, the pictures on the occlusal surfaces were recorded and saved. The sign above could be seen on the picture. The measuring tool in DIAGNOcam system was used to measure the depth of the caries from the sign (as starting point) to the deepest point of caries in the pictures and its length was recorded for a. The line a was lengthened to the contralateral edge of occlusal surface in the photo and the length was recorded for b. A line from the marked point on the occlusal surface edge of the extracted teeth was draw parallel to the line b on the corresponding photo and its length was recorded for c. The depth of the cavities on the projected images was recorded for d, and calculated d/a=c/b (digital optical fiber measured decay depth/caries damage depth of the image=actual tooth width/tooth width of the image), and d=c/b×a inferred. At last, the teeth were taken out from the standard model dentition. The decay of the tooth was removed completely. The actual depth of the cavity was recorded for D. The difference between d and D was recorded for Δd. The software of SPSS 20.0 was used to test the consistency of the results, and the MedCalc 14.8.1.0 software was used for Bland-Altman analysis.

RESULTS

The intraclass correlation coefficient (ICC) between d and D was 0.951 (ICC>75%), P=0.263. There was a function relationship y=0.23+0.91x between d(x) and D(y). Bland-Altman analysis method showed that the mean of Δd (Δdmean) was 0.05 mm, the standard deviation of Δd (ΔdSD)=0.308, and the 95% confidence interval was (-0.55 to 0.65). The amplitude of difference was clinically acceptable. So the consistency of the two measurement modes was high.

CONCLUSION

There was no significant difference between the depth of caries lesions checked with DIAGNOcam system and the depth of the actual cavity, and the consistency was very good. The vitro study suggests that the DIAGNOcam system may be used to assess the depth of caries cavity as a useful tool in diagnosis and treatment.

Effect of progranulin (PGRN) on the proliferation and senescence of cervical cancer cells

We investigated the effect of progranulin (PGRN) expression on the proliferation and senescence of cervical cancer cells. PGRN small interfering RNA (siRNA) was introduced into the SiHa and HeLa cell lines of human cervical carcinoma using liposome-mediated transfection. The expression levels of PGRN in each cell line after transfection of PGRN siRNA were detected by reverse transcription-polymerase chain reaction (RT-PCR). Senescence in the cell lines was detected using the β-galactosidase-staining test, and proliferation was detected by clone formation. The RT-PCR assay showed that the expression of PGRN in all of the cell lines transfected with PGRN siRNA markedly decreased. In the clone-forming test, compared with the control group, the colony-forming ability in all cell lines decreased significantly after transfection with PGRN siRNA. The β-galactosidase-staining experiments showed that the phenomenon of cell aging in the PGRN interference group was more obvious than in the control group. After the cervical cancer cells had been transfected with PGRN siRNA, cell senescence was accelerated and clone-forming ability was markedly reduced. This suggests that PGRN can promote the proliferation of the cervical cancer cell line; proliferation of cervical cancer cells is achieved by inhibiting their senescence.

Abstract P6-07-06: Primary prophylaxis of febrile neutropenia during adjuvant docetaxel and cyclophosphamide (TC) chemotherapy for breast cancer

Background: The combination of docetaxel and cyclophosphamide (TC) for adjuvant treatment of early stage breast cancer improves overall survival compared with doxorubicin and cyclophosphamide (AC) (Jones et al., 2006). Although cardiotoxicity is avoided with TC, the risk of febrile neutropenia (FN) is higher. For TC, reported rates of FN without prophylactic granulocyte colony-stimulating factor (G-CSF) range from 5% in the phase III trial to as high as 46% in retrospective chart reviews. G-CSF is not covered by our provincial cancer funding agency for primary prophylaxis of FN with TC chemotherapy, however it is often prescribed for patients with private insurance. Our aims were twofold: i) to determine the incidence of FN with TC chemotherapy with and without prophylactic G-CSF or antibiotics in two Ontario comprehensive cancer centres, and ii) to evaluate the cost-effectiveness of primary prophylaxis with G-CSF vs. antibiotics.

Methods: Patients who received adjuvant TC chemotherapy between January 1, 2008 and December 31, 2012 were identified through pharmacy databases. Electronic charts were retrospectively reviewed to extract patient characteristics, treatment details including G-CSF and antibiotic use, as well as incidence of FN and duration of hospitalization. A Markov model comparing primary G-CSF prophylaxis, primary antibiotic prophylaxis and secondary G-CSF prophylaxis was constructed to compare the cost-effectiveness of these strategies over a four cycle time horizon. Costs were based on resource utilization from this retrospective cohort and supplemented by the published literature, adjusted to 2012 Canadian dollars. The model took the perspective of the third party payer. Both one-way and probabilistic sensitivity analyses were performed.

Results: 340 patients were treated with TC over the study period. Of the 73 (21%) who did not receive any primary prophylaxis with G-CSF or antibiotics, 23 (32%) developed FN requiring hospitalization and treatment with intravenous antibiotics. However, only 2 of the 192 patients (1%; P &lt;0.0001) who received primary G-CSF prophylaxis (funded by the patient or a third party payer), and 6 of the 53 patients (11%; P &lt;0.01) who received primary antibiotic prophylaxis (97% receiving ciprofloxacin) developed FN. Age ≥65 was a significant risk factor for FN in the absence of G-CSF (56% vs. 25%, P = 0.02). The results of the cost-effectiveness analysis will be presented at the meeting.

Conclusions: The FN rate associated with TC chemotherapy without primary prophylaxis exceeds 30% but may be reduced with prophylactic antibiotics or G-CSF. Unless prophylactic antibiotics are substantially more cost-effective than prophylactic G-CSF for TC chemotherapy in a particular region or country, primary prophylactic G-CSF should be funded, given its greater effectiveness than antibiotics and the global need to minimize the emergence of antibiotic resistance.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-07-06.

Trichosanthes kirilowii: A New Host of Cucurbit mild mosaic virus in China

Chinese cucumber (Trichosanthes kirilowii Maxim.) is a type of perennial liana plant of the Cucurbitaceae family that is mainly distributed in East Asia and northern Australia. It is an important medicinal plant and commonly used in Chinese herbalism, where it is considered to be one of the 50 fundamental herbs (2). During the summer and autumn of 2012, T. kirilowii plants showing symptoms of mild mosaic on the upper leaves and bright yellow color on the lower leaves were observed in the Haidian district of Beijing, China. Recently similar symptoms induced by Cucurbit mild mosaic virus (CuMMV) on squash have been reported. CuMMV is a new member of the genus Fabavirus in the Comovirinae subfamily, discovered in China in 2006 (1). Total RNA was extracted from five leaf samples of independent plants and used for reverse transcription with an oligo (dT)₁₈ primer, followed by PCR with a pair of CuMMV virus-specific primers FaR₁3012F (5'-CGAGTGCGAGTTAGAAATTGGGATG-3') and FaR₁5783R (5'-TCACTTTGAGGTGATAAAACAATCC-3') to amplify a 2,772-bp fragment including RNA-dependent RNA polymerase (RdRp) coding region. The expected target fragment was obtained in all symptomatic plant samples but not from an asymptomatic plant. Nucleotide sequence comparison analysis showed that the virus isolated from T. kirilowii (GenBank Accession No. KC959843) had 95.33% nucleotide identity and 99.15% amino acid identity in the RdRp sequence with a CuMMV isolate from squash (GenBank Accession No. FJ194941) (1). In addition, symptomatic samples tested positive for CuMMV by Western blot using CuMMV small coat protein (SCP) specific polyclonal antibody (1). To our knowledge, this is the first report of T. kirilowii as natural host of CuMMV in China. The impact of CuMMV on T. kirilowii production remains to be determined; however, the extended host range for this virus suggests a potential threat of CuMMV to cucurbit crops in China. References: (1) S. W. Dong et al. Arch. Virol.157:597, 2012. (2) J. H. Hong et al. China Pharmacist 7:561, 2004.

Cerebral hyperperfusion syndrome after revascularization surgery in patients with moyamoya disease

Moyamoya disease (MMD) is a progressive occlusive disease of the distal internal carotid artery that is primarily treated by superficial temporal artery-middle cerebral artery (STA-MCA) bypass. Despite its effectiveness, several postoperative complications have been reported with STA-MCA bypass. Cerebral hyperperfusion syndrome (CHS) after STA-MCA has attracted considerable attention as a hemodynamics-related complication because more cases of CHS after STA-MCA bypass are reported in MMD than in non-MMD patients. The mechanisms underlying CHS after revascularization in MMD patients are poorly understood. This report presents a comprehensive review of the literature on CHS after revascularization in MMD patients, focusing on the pathogenesis, clinical features, imaging techniques, treatment, and prognosis of CHS. Impaired cerebrovascular autoregulation has been implicated in the pathogenesis of CHS, which is characterized by unilateral headache, face and eye pain, seizures, and focal neurological deficits secondary to cerebral edema, and intracranial hemorrhage. Imaging techniques, such as single photon emission computed tomography (SPECT), 3-T magnetic resonance imaging/angiography, and selective arterial spin-labeling magnetic resonance imaging, are valuable for identifying patients at risk for CHS. Treatment strategies include strict blood pressure control, intracranial hemorrhage prevention, and free oxygen radical scavenger administration. Most patients can achieve a satisfying prognosis after effective treatment.

Studies on interaction of cucurbit aphid-borne yellow virus proteins using yeast two-hybrid system and bimolecular fluorescence complementation

In this article, yeast two-hybrid system (YTHS) and bimolecular fluorescence complementation (BiFC) were used to analyze the interactions of cucurbit aphid-borne yellows virus (CABYV)-encoded proteins. P0, P1, P1-2, P3, P4, and P5 were tested by YTHS in all possible pairwise combinations, and only P3/P3 interaction was detected. Results obtained by BiFC further confirmed the self-interaction of P3, and the subcellular localization of reconstituted YFP fluorescence was observed mainly in nuclei of Nicotiana benthamiana leaf epidermal cells. Domains involved in P3/P3 self-interaction were analyzed by YTHS and BiFC using deletion mutants. The results showed that R domain (residues 1-61) in the N-terminus could self-interact, and it also interacted with the S domain (residues 62-199) in the C-terminus of P3. The present work would serve as a molecular basis for further characterization of CABYV proteins, and the regions involved in P3/P3 self-interaction could provide the clue for understanding the capsid assembly pathway of CABYV.

Anxiolytic-like activity of the mGLU2/3 receptor agonist LY354740 in the elevated plus maze test is disrupted in metabotropic glutamate receptor 2 and 3 knock-out mice

RATIONALE

(1S,2S,5R,6S)-2-Aminobicyclo[3.1.0]hexane-2,6-dicarboxylic acid (LY354740) is a potent and selective agonist for group II metabotropic glutamate (mGlu2 and mGlu3) receptors, with anxiolytic-like activity in animal and human models, and efficacy in anxiety patients. However, the lack of mGlu2 or mGlu3 receptor specific agonists has prevented in vivo characterization of individual functions of these two receptors in mediating the anxiolytic-like effects of LY354740.

OBJECTIVE

To utilize mGlu2 receptor and mGlu3 receptor knockout animals and the mGlu2/3 selective antagonist (2S,1'S,2'S)-2-(9-xanthylmethyl)-2-(2'-carboxycyclopropyl)glycine (LY341495) to further investigate the roles of mGlu2 and mGlu3 receptors in mediating the anxiolytic-like actions of LY354740 in a mouse model of anxiety [elevated plus maze (EPM) test].

METHODS

To confirm that mGlu2/3 receptors are responsible for anxiolytic-like activity in the EPM under these test conditions, mice were pretreated with LY341495 at 30 min prior to s.c. administered LY354740. Subsequently, saline vehicle or LY354740 was administered (s.c.) 30 min before the EPM testing in wild-type, mGlu2 receptor knockout, and mGlu3 receptor knockout mice.

RESULTS

LY354740 reduced in a dose-dependent manner anxiety-related behavior on the EPM in wild-type mice with a maximally effective dose of 10--20 mg/kg s.c. Pretreatment with LY341495 potently prevented the anxiolytic-like effects of LY354740 (20 mg/kg, s.c.) in mice. Although the mGlu2 receptor knockout and mGlu3 receptor knockout mice were grossly normal, the anxiolytic-like activity of LY354740 (20 mg/kg, s.c.) was not evident in either mGlu2 or mGlu3 receptor knockout mice, when compared to their wild-type controls.

CONCLUSIONS

The activation of both mGlu2 and mGlu3 receptors by LY354740 appears to be required for anxiolytic-like activity in the EPM test in mice. These studies serve as a foundation for additional studies on underlying circuits, brain structures, and receptor subtypes involved in the anxiolytic-like actions of mGlu receptor active agents, and the design of future drugs for anxiety disorders in humans.

Increased anxiety-related behavior in mice deficient for metabotropic glutamate 8 (mGlu8) receptor

Pre-synaptic metabotropic glutamate (mGlu) receptors modulate neuronal excitability by controlling glutamate and gamma-aminobutyric acid (GABA) release. The mGlu8 receptor is predominantly found in pre-synaptic terminals and its expression is highly restricted. To study the role of this receptor, mGlu8 receptor-deficient mice were generated. Here we report that naïve mGlu8 receptor-deficient mice showed increased anxiety-related behavior in the elevated plus maze in low illumination conditions (red light). Open arm avoidance and risk assessment behavior were both significantly increased in mutant mice. Increased stressfulness of the testing conditions abolished this behavioral difference. Fluorescent light or prior restraint stress decreased the open arm activity of wild-type mice, while the open arm activity of mutant mice was essentially unaffected, leading to similar values in both strains. The total number of arm entries or closed arm entries was not significantly different between strains, indicating that the lack of mGlu8 receptor does not affect locomotor activity. No gross behavioral changes, or changes in the function of the autonomic nervous system or somatomotor systems were observed in mutant mice. Moreover, no significant differences in seizure susceptibility were detected between strains. Our results suggest that mGlu8 receptor may play a role in responses to novel stressful environment.

Synthesis, characterization, and magnetic properties of carbon- and boron-oxide-encapsulated iron nanocapsules

Carbon- and boron-oxide-encapsulated iron nanocapsules have been synthesized by arc discharge in methane (CH4) and diborane (B2H6) atmospheres respectively. The characterization and magnetic properties of carbon- and boron-oxide-encapsulated iron nanocapsules [abbreviated as Fe(C) and Fe(B) respectively] were investigated and compared. The structure of the Fe(B) nanocapsules is different from that of the Fe(C) nanocapsules. The Fe(C) nanocapsules consist of a crystalline graphite shell and a core of alpha-Fe and/or Fe3C. The Fe(B) nanocapsules consist of an amorphous boron-oxide layer and a core of Fe(B) solid solution, alpha-Fe, gamma-Fe, FeB, and/or Fe3B phases. The saturation magnetizations of both the Fe(C) and the Fe(B) nanocapsules below 300 K decrease monotonically with increasing temperature. The coercivities of the Fe(C) and Fe(B) nanocapsules are almost 2 orders of magnitude higher than that of bulk Fe. The temperature dependence of magnetization at high temperatures indicates the existence of some phase transformations.

Acupuncture effects on reflex responses to mental stress in humans

In animal studies, acupuncture has been shown to be sympathoinhibitory, but it is unknown if acupuncture is sympathoinhibitory in humans. Nineteen healthy volunteers underwent mental stress testing pre- and postacupuncture. Muscle sympathetic nerve activity (MSNA), blood pressure, and heart rate during mental stress were compared pre- and postacupuncture. Control acupuncture consisted of acupuncture at nonacupoints and "no-needle" acupuncture. Acupuncture had no effect on resting MSNA, blood pressure, or heart rate. After real acupuncture, the increase in mean arterial pressure (pre- vs. postacupuncture 4.5 vs. 1.7 mmHg, P < 0.001), but not MSNA or heart rate, was blunted during mental stress. Similarly, following nonacupoint acupuncture, the increase in mean arterial pressure was blunted during mental stress (5.4 vs. 2.9 mmHg, P < 0.0003). No-needle acupuncture had no effect on these variables. In conclusion, acupuncture at traditional acupoints, nonacupoints, and no-needle acupuncture does not modulate baseline MSNA or MSNA responses to mental stress in normal humans. Acupuncture significantly attenuates the increase in blood pressure during mental stress. Needling nonacupoints, but not "no-needle" acupuncture, have a similar effect on blood pressure.

[Expression of single-chain Fv antibody for anti-beet necrotic yellow vein virus in Escherichia coli]

The heavy chains variable region gene (VH) of monoclonal antibody against beet necrotic yellow vein virus (BNYVV) was amplified from total DNA extracted from anti-BNYVV hybridoma cells by PCR. Sequencing showed that the VH belongs to mouse subgroup II(A) and contains 360 bp, which code one hundred and twenty amino acids. The VH and VL genes were inserted into a plasmid which contains a linker sequence for constructing scFv gene. The new vector named pTC scFv. The scFv was produced in Escherichia coli and appeared binding activity with BNYVV antigen by ELISA method.

Study on antimicrobial susceptibility of bacteria causing neonatal infections: a 12 year study (1987-1998)

OBJECTIVE

The method of Manual of Clinical Microbiology was used to identify bacteria. We investigated the epidemiological characteristics of bacterial agents and their antimicrobial susceptibility as empirical treatment for neonatal infections. Disk diffusion tests were also done for antimicrobial susceptibility.

RESULTS

From January 1987 to December 1998, 2,244 bacterial strains were isolated in our neonatal ward. The first three predominant species were Staphylococcus epidermidis (23.9%), Staphylococcus saprophyticus (19.9%) and Escherichia coli (12.6%) in group I (infections acquired outside of hospital). Escherichia coli, Klebsiella and Pseudomonas aeruginosa accounted for 18%, 15.2% and 12.6% respectively in group II (nosocomial infections). The sensitivity rates of those antimicrobials that are seldom used for newborns were found to be higher, while the resistant rates of the commonly used antimicrobial drugs have increased significantly. The resistant rates of bacterial isolate from group II to antimicrobial agents including penicillin and ampicillin were significantly higher than those isolated from group I (p<0.05)The sensitivity rate was 82.2% (717/833) by using amikacin only, when combined with penicillin, rose to 89%(741/833).

CONCLUSIONS

Gram-negative bacteria were mainly responsible for nosocomial infections of neonates in our hospital. Infections acquired outside the hospital were mainly caused by Gram-positive bacteria. Nosocomial pathogens produced drug resistance easily. Combination of amikacin and penicillin can be recommended as the initial antibiotics for treatment of neonatal infections.

[Genescan for STR analysis and genetic distribution in a population sample from Han, China]

Genetic distributions for nine STR loci and Amelogenin locus were determined in a Chinese Han population based on DNA sequencing. The databanks in Chinese Population were generated by using Genescan, genotype and genetic distribution analysis. Allele frequency distribution was determined for 10 loci, such as D3S1358, VWA, FGA, Amelogenin, THO1, TPOX, CSF1PO, D5S818, D13S317 and D7S820. The results show significant differences between ethnic groups (African-American, US-Caucasian and Chinese Han) in the pattern of distribution as well as in the related frequency of the most common alleles of their STR loci. The probabilities of identity values for the population described in this section are 2.79 x 10(-10) (U.S-Caucasian), 1.23 x 10(-10) (African-American) and 0.5 x 10(-10) (Chinese Han). The results show the probability of Paternity Exclusion (PPE) values of 0.9998 (Chinese Han), 0.9996 (African-American) and 0.9994 (U.S-Caucasian). These results suggested that the nine STR loci and the Amelogenin locus are very useful for human identification, such as analyzing forensis casework, establishing DNA databanks, processing paternity test, evaluation linkage genetics, studying gene natural resources and monitoring bone marrow transplants.

Oncogenes and angiogenesis: signaling three-dimensional tumor growth

Three-dimensional tumor growth is dependent on the perpetual recruitment of host blood vessels to the tumor site. This recruitment process (mainly via angiogenesis) is thought to be triggered, at least in part, by the very same set of genetic alterations (activated oncogenes, inactivated/lost tumor suppressor genes) as those responsible for other aspects of malignant transformation (e.g., aberrant mitogenesis, resistance to apoptosis). Potent oncogenes are able to deregulate expression of both angiogenesis stimulators and inhibitors in cancer cells. For example, mutant ras expression is associated with increased production of vascular endothelial growth factor (VEGF) and downregulation of thrombospondin-1 (TSP-1). Upregulation of VEGF and angiogenesis can also be induced by constitutive activation of other oncogenic proteins (e.g., EGFR, Raf, MEK, PI3K) acting at various levels on the Ras signaling pathway. The mode and the magnitude of such proangiogenic influences can be significantly modified by cell type (fibroblastic or epithelial origin), epigenetic factors (hypoxia, changes in cell density), and/or presence of additional genetic lesions (e.g., preceding loss of p16 or p53 tumor suppressor genes). Activated oncogenes (e.g., ras, src, HER-2) induce co-expression of angiogenic properties concomitantly with several highly selectable traits (increased mitogenesis, resistance to apoptosis), a circumstance that may accelerate selection of the angiogenic phenotype at the cell population level. On the other hand oncogene-induced reduction in growth requirements may also endow tumor cells with a diminished (albeit not abrogated) dependence on (close) proximity to blood vessels, i.e., with reduced vascular dependence. Thus, oncogenes can impact several interconnected aspects of cellular growth, survival, and angiogenesis. Experimental evidence suggests that, in principle, many of these properties (including angiogenesis) can be simultaneously suppressed (and tumor stasis or regression induced) by effective use of the specific oncogene antagonists and signal transduction inhibitors.

High-frequency color flow imaging of the microcirculation

The extension of ultrasound (US) color flow imaging (CFI) techniques to high frequencies (> 20 MHz) has the potential to provide valuable noninvasive tools for scientific and clinical investigations of blood flow in the microcirculation. We describe the development of a slow-scan CFI system operating in the 20-100-MHz range that has been optimized to image the microcirculation. The apparatus has incorporated elements of a previously reported pulsed-wave Doppler system and is capable of operating in either CFI or pulsed-wave mode. The performance of the CFI system was evaluated at a center frequency of 50 MHz using two PVDF transducers with -6-dB beam widths of 43 and 60 microm. The -6 dB-axial resolutions were estimated to be 66 and 72 microm, respectively. In vivo validation experiments conducted using the murine ear model demonstrated the detection of flow in vessels down to 15-20 microm in diameter with flow velocities on the order of mm per s. Further experiments examining experimental murine tumors confirmed the successful detection of flow in the tumor microcirculation.

Binding of immobilized fibronectin by biliary drain isolates

Occlusion of biliary stents, as the result of bacterial adhesion and colonization onto biliary stents, still remains a major problem. Biliary proteins, such as fibronectin (Fn) and vitronectin (Vn), have been presumed to be involved in the process of bacterial adhesion to biliary biomaterial. In the present study, Fn binding by 5 strains of E. coli isolated from biliary drains or from bile was studied. All strains did not bind detectable amounts of soluble Fn but bound to immobilized plasma Fn. Adhesion of four strains of E. coli to ovalbumin was reduced by periodate treatment of ovalbumin, but adhesion to Fn was unaffected. Adhesion was inhibited by mannose-containing saccharides, trypsin treatment of the protein, and protease treatment of the bacterial cells. Autoradiography showed that components of cell extracts from three E. coli strains bind 125I-Fn but not a 150 kD Fn fragment. The findings indicate that the adhesion of these bacteria to Fn is a protein-protein interaction, inhibited by D-mannose, and possibly mediated by fimbrial components.

Fibronectin binding by Propionibacterium acnes

Strains of Propionibacterium acnes, isolated from different kinds of orthopaedic and biomaterial-associated infections and from skin flora were shown to express binding of soluble as well as immobilized fibronectin. Among these 7 strains isolated from orthopaedic infections, 2 from breast prostheses, and 9 skin isolates, 2, 2, and 5 strains respectively bound immobilized fibronectin. The fibronectin binding was sensitive to protease and heat treatment, and was inhibited by a cell surface extract from one of the binding strains. In SDS-PAGE and autoradiography of cell surface extracts, a band corresponding to a MW of about 80 kD reacted with fibronectin and the 150 kD fragment of fibronectin. Binding to fibronectin and the 150 kD fragment of fibronectin could be inhibited with heparin. We thus present a first Fn binding protein of P. acnes, a surface exposed protein of 80 kD. None of the strains bound soluble collagen, and only one strain expressed weak binding of vitronectin and bone sialoprotein II.

Fibronectin exposes different domains after adsorption to a heparinized and an unheparinized poly(vinyl chloride) surface

The adsorption of fibronectin to poly(vinyl chloride) catheters with end-point attached (EPA) heparin and tridodecylmethylammonium chloride-heparinized poly(vinyl chloride) was compared to that of unheparinized poly(vinyl chloride) using antibodies directed against four different domains of the protein. After perfusion of human plasma on the EPA-heparinized surface, the exposure of the N-terminal 29-kD fragment increased during the first 5 h of perfusion. Also, the exposure of the 30-kD gelatin-binding and 65-kD cell-binding fragments increased with time, but at a lower level. On the unheparinized catheter, low levels of antibodies bound to the different domains, and the binding showed little variation during the 5 h of plasma perfusion, indicating that the fibronectin molecule does not change configuration to a significant extent on this surface after the initial adsorption. When the EPA-heparinized surface was preabsorbed with human fibrinogen before incubation with fibronectin, significantly less of the 29-kD (fibrin-binding) domain was exposed, and the 30-kD domain was not exposed. Exposure of the 31- and 65-kD domains increased after preadsorption of fibrinogen to the surface. Since fibronectin has heparin-binding domains, it adsorbs differently to a heparinized versus an unheparinized surface. This will influence subsequent binding of other proteins to the surface, as well as potential binding of microbes. The use of antibodies to defined domains of the fibronectin molecule provides a powerful tool in studies of configurational changes of fibronectin after adsorption to different surfaces.

Protein adsorption and bacterial adhesion to biliary stent materials

Four biliary stents inserted for relief of jaundice in patients with biliary obstruction due to carcinoma of pancreatic head were examined for the adsorption of biliary proteins and bacterial colonization. Fibronectin and vitronectin (S-protein) were found to be the two main proteins adsorbed on the inner surface of the stents. Biliary isolates included Escherichia coli, Enterococcus faecalis, and Candida albicans. In vitro studies were performed to clarify the kinetics of biliary protein and bacterial adhesion. Biliary drains of polytetrafluorethylene, polyethylene, polyurethane, and rubber were placed in a flow cell and perfused with human bile at 37% C for 24 hr. The materials were subjected to either detection of adsorbed biliary proteins or perfusion with 3 H-labeled E. coli cells (1 X 10 6 cfu/ml). The results show that the adsorbed biliary proteins were detectable on the surface of biliary stents and able to enhance bacterial adhesion to the surface in the first 24 hrs after the exposure of stent materials to bile, and that both the adsorption of biliary proteins and the adhesion of bacterial cells were material- and strain-dependent. Furthermore, there was a clear correlation between the amount of adsorbed fibronectin and the number of adherent bacteria. The results indicate that, in the clinical situation, biliary proteins may be adsorbed on the surface of inserted stents within a short time after insertion, and some of them may be used by bacterial cells as receptors for adhesion to the surface, and thus involved in the process of bacterial adhesion.

A bacteriologic and scanning electron microscope study after implantation of foreign bodies in the biliary tract in rats

BACKGROUND

Bacterial adherence to the stent surfaces, concomitant colonization, and possible stent blockage are the main complications after the use of biliary stents. The present study was assigned to investigate bacteriologic and morphologic changes in the biliary tract after the implantation of biliary drain materials.

METHODS

Rubber and silicone pieces with a surface area of 1 cm2 were implanted into the biliary tract in rats after temporary obstruction of the common bile duct by the use of a mini-occluder. The animals were killed at 4, 8 and 14 weeks, respectively, after implantation, and the implants were retrieved, cultured, and examined by scanning electron microscopy (SEM). Bacterial culture and SEM were also performed on tissue samples obtained from the mucosal surface of the biliary tract.

RESULTS

Bacterial colonization and biofilm formation were found on the surfaces of the implanted materials and on the mucosal surface of the biliary tract in animals with implants but not on the biliary tract mucosa in rats without implants.

CONCLUSION

Foreign bodies implanted in the biliary tract facilitate bacterial adherence not only to the surface of the implants but also to the mucosal surface in the biliary tract.

Fibronectin on the surface of biliary drain materials--a role in bacterial adherence

The present study deals with the demonstration of deposited fibronectin (Fn) on the surfaces of implanted biliary drain materials and the role of deposited Fn in promotion of bacterial adherence. Rubber pieces that had been implanted in the biliary tracts of rats for 4 weeks were retrieved and the following approaches employed for further investigations: (1) adherence of [methyl-3H]thymidine-labeled Escherichia coli to implanted and unimplanted rubber pieces; (2) blocking the adherence of radiolabeled bacteria with anti-Fn antibodies; (3) detection of deposited Fn by 125I-labeled anti-Fn IgG; and (4) immunoblotting of the surface eluate from implanted rubber pieces. The results show that in the presence of serum, plasma, or bile, the number of E. coli cells adherent to implanted rubber pieces was 10 times higher than that adherent to the unimplanted pieces (P < 0.001) and that the adherence was reduced by pretreatment of implanted pieces with anti-Fn antibodies. Furthermore, the implanted pieces appeared to have a high affinity for 125I-labeled rabbit anti-Fn IgG rather than the 125I-IgG without anti-Fn fraction. Fn was also found in the surface eluate of implanted pieces by immunoblotting of the eluate. The results in the present study suggest that Fn may be involved in implant-associated infections in the biliary tract.

Experimental foreign-body infection in the biliary tract in rats

BACKGROUND

Biomaterials used for biliary drainage may potentially result in biomaterial-associated infections.

METHODS

Foreign-body infection in the biliary tract was investigated in rats. Rubber drain pieces were implanted in the biliary tract in rats for 1-4 weeks, followed by challenges with 10(2) to 10(4) colony-forming units (cfu) Escherichia coli injected into the common bile duct. The rate of infection was calculated, the bacterial growth in the biliary tract was observed over 72 h after challenges, and the opsonic activity in bile and in sera was assessed.

RESULTS

In the group with drain material, inocula as small as 10(2) cfu produced persisting infection in the common bile duct in 90% of animals, whereas the same number of E. coli infected only 30% of rats in the control and sham implantation groups (p < 0.01, chi-square test). Complement-mediated opsonic activity in bile of animals with implanted drain pieces gradually decreased with time, whereas opsonic activity in sera from the same animals remained unchanged.

CONCLUSIONS

Implants in the biliary tract impair local host defense, resulting in an increased susceptibility to microbial infection.

Promotion of Escherichia coli adherence to rubber slices by adsorbed fibronectin

Biomaterial-associated infections are a problem in the use of endoprosthetic materials in the palliative treatment of malignant obstructive jaundice. Fibronectin has been reported to mediate adherence of bacteria to host tissue and biomaterials. Adsorption of fibronectin to rubber--representing material used for biliary drainage--and subsequent adherence of Escherichia coli strain PSS1 and E. coli strain NG7C (which binds to immobilised fibronectin) were investigated. Quantitative adsorption of fibronectin to rubber slices was studied with 125I-labelled, purified human plasma fibronectin. In buffer solutions, fibronectin showed a high affinity for rubber slices. Adherence of the E. coli strains to uncoated rubber slices was similar and was significantly inhibited by the presence of plasma components and bile. Adherence of E. coli PSS1 to fibronectin-coated slices was poor. In contrast, E. coli NG7C adhered efficiently to coated slices in proportion to the amount of adsorbed fibronectin; adherence was not reduced by the presence of albumin or bile, or the fibronectin-binding ligands gelatin, heparin and fibrinogen. However, pre-digestion of coated slices with trypsin significantly reduced adherence.