The effect of alar cinch sutures and V-Y closure on soft tissue dynamics after Le Fort I intrusion osteotomies

Adverse effects on the soft tissues after Le Fort I osteotomies include: broadening of the alar base, loss of vermilion show of the upper lip and down sloping of the commissures. In theory, an alar cinch suture combined with a muco-musculo-periosteal V-Y closure (ACVY) should improve not only the nasal width, but would also improve the dynamics of some of the mimic muscles. To test the validity of this hypothesis, a prospective study was set up including 22 patients, using standardized full facial frontal photographs, taken immediately preoperatively and 18 months postoperatively. Sets containing three pictures were made: soft tissue in repose, maximum closed mouth smile and maximum smile. The landmarks, alare, crista philtri and cheilion were analysed. The preliminary results show that ACVY-closure does significantly improve the horizontal movement of cheilion with both maximum closed mouth smile and maximum smile, as well as the vertical movement of crista philtri with maximum closed mouth smile.

CONCLUSION

The Le Fort I osteotomy with ACVY improves the orofacial dynamics.

Use of intraoperative breast cancer sentinel lymph node (SLN) assay to predict of ≥4 positive (+) lymph nodes (LN)

530

Background: Predicting which patients will have ≥4 +LN and may need radiation therapy affects immediate breast reconstruction. We hypothesized that model s to predict the likelihood of ≥4+LN may be improved by incorporation of quantitative real time RT-PCR analysis of SLN. Methods: 728 patients were enrolled in 2 prospective studies of the GeneSearch BLN Assay (Veridex LLC) for SLN metastases. 205 (28.2%) were found to have +SLN by hematoxylin-eosin staining. Of these, 115 pts (15.8%) had tumors ≤5 cm in size with >4 total LN removed, forming the cohort of interest for this study. Quantitative cycle times (CT) for mammaglobin (MG) and CK19 were correlated with finding ≥4+LN on final pathology. Results: Median tumor size was 2.0 cm (range; 0.2–5.0 cm). Median number of SLN removed was 3 (range; 1–11). 18 patients (15.7%) had ≥4 +LN on final pathology. Median CT for MG was 29.1 (interquartile range (IQR): 24.7–39.0) in patients with <4 +LN vs. 21.4 (IQR: 18.5–26.8) in those with ≥4 +LN, p<0.001. Median CT for CK19 was 23.7 (IQR: 20.9–28.2) in patients with <4 +LN vs. 19.6 (IQR: 17.8–20.7) in those with ≥4 +LN, p<0.001. Tumor size ≥2cm, proportion of SLN+ >50%, MG CT <25.8 and CK19 <20.8 were correlated with ≥4 +LN on final pathology. On multivariate analysis, tumor size, MG CT and CK19 CT were significant (see table). A simplified CPR was created with 1 point given if tumor size was ≥2cm, 1 point if MG CT <25.8 and 2 points if CK19 CT<20.8. Of the 24 patients (20.9%) with 0 points, only 1 (4.2%) had ≥4 +LN; of the 12 patients (10.4%) with 3 points, 8 (66.7%) had ≥4 +LN on final pathology, p<0.001. Area under the receiver-operator curve was 86.2% (95% CI: 76.1%-96.2%). Conclusions: Intraoperative quantitative RT-PCR of SLN improves prediction of ≥4 +LN; further validation of this model will have clinical utility regarding the use of immediate, delayed, or delayed-immediate reconstruction approaches.

[Table: see text]

[Table: see text]

A phase II study of capecitabine (CAP) plus PHY906 in patients (pts) with advanced pancreatic cancer (APC)

e15508

Background: Gemcitabine (G) is regarded as the standard treatment for pts with APC. However, a standard second-line chemotherapy regimen has yet to be defined after G. PHY906, a 4-herb traditional Chinese medicine has a history of > 1,800 yrs of human use to treat GI symptoms including diarrhea. Preclinical studies showed that PHY906 may potentiate antitumor activity of CAP in human PANC-1 xenograft (ASCO 2007). A phase I study showed that CAP can be escalated up to 1750 mg/m2 PO BID on d1- 7 and PHY906 800mg PO BID on d1–4 q 2 wks with no DLTs (ASCO, 2008). Delivered dose-intensity of CAP was similar at 1750mg/m2 dose level as 1500mg/m2. Therefore, 1500mg/m2 of CAP and PHY906 was further tested in a phase II study as second-line treatment in pts with APC. Methods: Pts with G-refractory APC with ECOG PS <2 were treated with CAP 1500mg/m2 d1–7 with PHY906 800mg d1–4 q 2 wks. Response was assessed by CT scan according to RECIST q 6 wks and toxicity according to NCI-CTC v3.0. Primary objective is overall survival. Secondary objectives include overall RR, PFS and measurement of cytokines to assess inhibition of NF-kappa B, a possible mechanism responsible for PHY906's pharmacological activity. Results: As of January 5, 2009, 25 pts have been enrolled. Baseline characteristics include median age, 65 (range, 40–85); male/female,15/10; ECOG PS 0/1, 4/19; median cycles: 3 (r: 0.5–15). At this point 5 pts are still in active treatment. 4 pts have confirmed OS > 6 ms (1 still on study) with 2 further pts approaching 6 ms. Among evaluable pts, 1 had PR (5.3%), 11 SD (57.9%) and 7 PD (36.8%) after initial restaging scan. 36 % pts had >30% reduction in CA19–9 as biochemical response. There were 7 deaths on/within 30 days of study treatment, 6 related to PD and 1 had acute MI. G3/4 toxicities diarrhea 3/25 (12%), fatigue, 1/25 (4%), HFS 1/25 (4%) and mucositis 1/25 (4%). 1 pt was removed from study due to G3 HFS. Biomarker studies (IL4, GM-CSF, TNF-alpha, IL10, MCP-1, IL2, IL6) are ongoing. Conclusions: This is the first clinical study to evaluate a botanical formulation PHY906 with CAP in G-refractory APC pts. CAP + PHY906 regimen appears a safe and feasible salvage therapy in APC and warrants further investigation. In addition, PHY906 may have a cytoprotective antidiarrheal and anti-HFS effect, making treatment with CAP more tolerable.

[Table: see text]

Protein expression comparison and physiological profiling of matched pairs DCIS/normal and invasive/normal primary epithelial cells

Abstract #6031

Background: Approximately 50% of patients who are diagnosed with Ductal Carcinoma In-Situ (DCIS) develop invasive breast cancer. The progression from DCIS to invasive cancer is not well understood. To better understand the range of biological processes involved in this progression, we have successfully isolated primary epithelial cell cultures from patient breast tissue and are using mass spectrometry-based methods to identify differentially expressed proteins in these different cell types. Bioinformatics analysis was used to identify differences in the underlying pathways.&#x2028; Methods: Primary Human Mammary epithelial cells from DCIS and Stage 3 Invasive tumors and normal tissue from the same patient were isolated immediately after surgery. Cells were maintained in defined CNT27 media for up to 2 passages and were characterized for epithelial and breast cancer markers by immunohistochemistry and western blot. Tamoxifen response was measured by cell proliferation assay. Protein lysates were labeled with the ITRAQ isobaric tags. Two-dimensional high-pressure liquid chromatography and mass spectrometry were used to identify differentially expressed proteins.&#x2028; Results: The proliferation rate of cells from DCIS tissue was 33% higher than the matched control cells and 50% higher from invasive tissue. Furthermore, Tamoxifen was more effective at inhibiting DCIS cell proliferation than the invasive cells in a dose- and time-dependent manner. We identified 50-100 proteins differentially expressed between the different tissue types. Validated tumor markers such as members of protein S100 family were significantly different between the tumor and normal samples. Thrombospondin, a known angiogenesis inhibitor, had similar concentrations in normal and DCIS tissues but was down-regulated (ratio=0.4) in the invasive tumor samples.&#x2028; Discussion: Using the analogous methods from gene expression studies, we found that pathways associated with processes such as differentiation, angiogenesis, and invasion are enriched in the proteome of the invasive tumors. Further comparisons of additional samples is continuing with the goals of better understanding the underlying biology that drives DCIS to invasive breast cancer and ultimately defining markers that could be used in better prognosis for DCIS patients.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6031.

Pathogenesis and therapeutic approaches for improved topical treatment in localized scleroderma and systemic sclerosis

SSc is a chronic progressive disorder of unknown aetiology characterized by excess synthesis and deposition of collagen and other extracellular matrix components in a variety of tissues and organs. Localized scleroderma (LS) differs from SSc in that with LS only skin and occasionally subcutaneous tissues are involved. Although rarely life threatening, LS can be disfiguring and disabling and, consequently, can adversely affect quality of life. There is no known effective treatment for LS, and various options, including, as examples, corticosteroids and other immunomodulatory agents, ultraviolet radiation and vitamin D analogues, are of unproven efficacy. Clinical trials evaluating combination therapy such as corticosteroids with MTX or UVA1 exposure with psoralens have not been established as consistently effective. New immunomodulators such as tacrolimus and thalidomide are also being evaluated. A better understanding of the molecular and cellular mechanisms of LS has led to evaluation of new treatments that modulate profibrotic cytokines such as TGF-beta and IL-4, regulate assembly and deposition of extracellular matrix components, and restore Th1/Th2 immune balance by administering IL-12 or IFN-gamma. IFN-gamma acts by directly inhibiting collagen synthesis and by restoring immune balance. In this review, we evaluate current and future treatment options for LS and cutaneous involvement in SSc. Recent advances in therapy focus mainly on anti-fibrotic agents. Delivery of these drugs into the skin as the target tissue might be a key factor in developing more effective and safer therapy.

Characterization of a multiple ligand-gated ion channel cellular membrane affinity chromatography column and identification of endogenously expressed receptors in astrocytoma cell lines

Cellular membranes obtained from the 1321N1 and A172 astrocytoma cell lines were immobilized on a chromatographic phase to create cellular membrane affinity chromatography (CMAC) columns, CMAC(1321N1) and CMAC(A172). The columns were characterized using frontal affinity chromatography with [(3)H]-epibatidine as the marker ligand and epibatidine, nicotine, and methyllycaconitine as the displacers. The results indicated that the columns contained homomeric alpha7 nicotinic acetylcholine receptors (alpha7 nAChR) and heteromeric nicotinic acetylcholine receptors (alpha(x)beta(y) nAChRs), which was confirmed by the addition of subtype-specific inhibitors, alpha-bungarotoxin (alpha7 nAChR) and kappa-bungarotoxin (alpha(x)beta(y) nAChR) to the mobile phase. The presence of two additional ligand-gated ion channels (LGICs), gamma-aminobutyric acid (GABA(A)) and N-methyl-D-aspartic acid (NMDA), was established using frontal affinity chromatography with flunitrazepam and diazepam (GABA(A) receptor) and MK-801 and NMDA (NMDA receptor). The presence of the four LGICs was confirmed using confocal microscopy and flow cytometry. The results indicate that the CMAC(1321N1) and CMAC(A172) columns contain four independently functioning LGICs, that the columns can be used to characterize binding affinities of small molecules to each of the receptors, and that the CMAC approach can be used to probe the expression of endogenous membrane receptors.

Optical properties of a bio-inspired gradient refractive index polymer lens

The design, fabrication, and properties of one of a new class of gradient-index lenses are reported. The lens is an f/2.25 GRIN singlet based on a nanolayered polymer composite material, designed to correct for spherical aberration. The light gathering and focusing properties of the polymer lens are compared to a homogeneous BK7 glass singlet with a similar f-number. The modulation transfer function of the polymer GRIN lens exceeded that of the homogeneous glass lens at all spatial frequencies and was as much as 3 times better at 5 cyc/mm. The weight of the polymer lens was approximately an order of magnitude less than the homogeneous glass lens.

The reliability of frontal facial photographs to assess changes in nasolabial soft tissues

A simple, modified method to evaluate changes in the nasolabial soft tissues after orthognathic surgery is presented. Eighteen healthy volunteers were photographed in a standardized manner with a 2-month interval. Pictures were taken with the soft tissues in repose and 'maximum closed mouth smile'. Discrepancies for repose and dynamic excursions (x and y coordinates) were calculated for the landmarks alare, crista philtri and cheilion. Multiple analysis of variance revealed no significant interaction for intra-observer variance and time of recording. Coefficients of reliability (repose: 90-99%, dynamic excursion (cheilion): >95%), Spearman correlation coefficients (repose: >0.8, dynamic: >0.6) and squared correlation (repose: >75%, dynamic: >50%) showed this method to be reliable for repose and dynamic excursions. The error of measurement was less than 1.8 mm for both repose and dynamic excursions (SD(differences)=0.9 mm). This is smaller than mean differences in nasolabial soft-tissues excursions found between the pre- and post-Le Fort I osteotomy situation in a previous study using video imaging. The discrepancies found were in keeping with other earlier reports for 2D and 3D measuring methods. The method as proposed is simple, cost effective and can be used to evaluate soft-tissue changes after orthognathic surgery.

Self-exam is the most common method of breast cancer identification

1543

Background: Breast cancer survival is improved by early diagnosis. The role of self-exam as an adjunct to screening mammography has been questioned as some studies suggest that self-examinations lead to unnecessary diagnostic procedures without improving survival. Methods: Patients who had been diagnosed with breast cancer and who were attending a university-based cancer clinic were interviewed, using a structured questionnaire, to determine the way in which their breast cancers were first identified. Inference was conducted using exact methods (Clopper-Pearson intervals for proportions and Fisher’s test for odds ratios). Results: Breast cancers were first identified by mammogram in 16% of women, by provider in 9%, by the spouse in 2%. Seventy-five percent (95% CI=61% to 85%) of patients first identified their tumors by self exam. Self-identifiers occurred in all demographic groups. These women included those with all types of insurance: private insurance (68%), Medicare (60%), Medicaid (100%), or no insurance (85%); all levels of education: 77% with college education and 75% with high school; all income levels: for example, among 79% with annual incomes of <$10K and 73% with incomes >$50K; and among both black (91%) and white (66%) women. Of the women who reported both regular mammograms and regular self-examination (N=35), 77% (95% CI=60 to 90%) were self-identifiers. However, cancers found by mammography were more likely to be Stage I than were those identified by self-examination (odds ratio=3.9, 95% CI .9 to 17.5, p=.047). Conclusions: Most breast cancers (75%) were found by self-examination, even among women who had regular mammography. We did not find any demographic factor that predicted mammography as the primary method of tumor identification. These findings suggest that self-examination remains an important method of breast cancer identification.

No significant financial relationships to disclose.

Functional results after conservative treatment of fractures of the mandibular condyle

Since the introduction of osteosynthesis materials for rigid internal fixation after anatomical reduction there is an ongoing discussion about the treatment of condylar fractures of the mandible. Sixty patient files were analyzed and 28 patients were seen for re-examination and a x-orthopantomogram was taken. Functionality was graded with the Helkimo index at an average of 3.0 years follow-up. The clinical dysfunction index showed: severe symptoms in 11%, moderate symptoms in 39%, mild symptoms in 39% and 11% had no symptoms. Index for occlusal state showed: 21% severe occusal disturbances, 61% moderate occlusal disturbances and 18% no occlusal disturbances. According to the anamnestic dysfunction index 89% of the patients were symptom-free. The clinical outcome group showed a significant left/right ramus length difference compared with a 20-person control group. The re-examined group did not significantly differ from the control group. Conservative treatment for condylar fractures was successful in only 46% according to the 1999 consensus criteria described by Bos et al.

Factors predicting tumor size at presentation in breast cancer patients

10609

Background: Early diagnosis of breast cancer improves prognosis. A high percentage of women at our institution present with large breast cancers. Using tumor board records, we investigated the potential covariates associated with tumor size at presentation, including age, race, marital status, and insurance status in order to identify populations at risk for presenting with late stage disease. Methods: Data were obtained from tumor board records of University Health Systems, Greenville, NC, a regional referral center in rural Eastern North Carolina. We analyzed data from patients presenting between 1999 and 2005. Relationships between tumor size at diagnosis and explanatory variables (marital status, age, ethnicity, and insurance status) were explored. Results: 1568 patients with breast cancer were identified of which 32% were African American (AA), 67% were White (W), and 0.6% other. 8.3% of patients had Medicaid; 27%, Medicare; 53.5%, private insurance; 3.4%, HMO; and 6.1% were uninsured. Tumor size was 0.01 to 25 cm and highly skewed so that statistical inferences were conducted on the log of tumor size. Tumors of >5 cm were found in 13.8% of AA women as compared to 6.4% of W women. Overall tumor size in AA women was larger than in W women (p-value = .0000). Marital status was not statistically significant (p-value = .5148). A linear regression model for log tumor size at time of diagnosis using explanatory variables marital status, age, ethnicity, and insurance status showed that only race (p-value = .0000) and age (p-value = .0004) were statistically significant. Older patients presented with somewhat smaller tumors. Most of the variability in log tumor size remained unexplained (r-squared = 4%). Conclusions: AA women were more likely to present with large tumors. While Medicaid patients had larger tumors, insurance status was not statistically significant in the linear regression model due to partial confounding of insurance and race: 20.8% of AA women were on Medicaid compared to 2.6% of W women.

No significant financial relationships to disclose.

Mild traumatic brain injury induces persistent cognitive deficits and behavioral disturbances in mice

Victims of mild traumatic brain injury (mTBI) do not show clear morphological brain defects, but frequently suffer from long-lasting cognitive deficits, emotional difficulties and behavioral disturbances. In the present study, we investigated the effects of experimental mTBI in mice on cognition, spatial and non-spatial tasks, and depressive-like behavior in mice. Experimental brain injury was induced using a concussive head trauma, which creates the TBI by a weight-drop device. Different groups of mice were tested at 7, 30, 60, and 90 days post-injury for cognitive function (the swim T-maze and the passive avoidance test) and for depression-like behavior (the forced swimming test). These tests have been used infrequently in the past in mTBI research. Significant differences were observed between the injured mice compared to the controls in both the swim T-maze (day 30: p < 0.001) and passive avoidance (day 30: p < 0.05) tests. In addition, a significant difference was detected in the forced swimming test between the injured mice and the controls (day 7: p < 0.05; day 90: p < 0.01), which showed a depressive- like state in the injured animals beginning 7 days post-injury. These results demonstrate that persistent deficits in these tests of cognitive learning abilities and emergence of depressive-like behavior in injured mice are similar to those reported in human post-concussion syndrome.

Guided resonances in asymmetrical GaN photonic crystal slabs observed in the visible spectrum

We demonstrate that guided resonant modes can be readily observed in asymmetrical photonic crystal slabs on high-index substrates. In spite of the high radiative loss associated with all optical modes in these cases, the guided resonant modes are found to give rise to strong high-Q features in the transmission spectra. Since these photonic crystal structures are far more robust and easier to fabricate than the free-standing photonic crystal membranes used in previous studies of guided resonant modes, detailed studies of relevant optical phenomena and the implementation of proposed applications are greatly simplified.

Changing of hepatitis C virus genotype patterns in France at the beginning of the third millenium: The GEMHEP GenoCII Study

This cross-sectional study aimed to investigate, during a short period between 2000 and 2001, in a large population of patients with chronic hepatitis C, the epidemiological characteristics of hepatitis C virus (HCV) genotypes in France. Data from 26 referral centres, corresponding to 1769 patients with chronic hepatitis C were collected consecutively during a 6-month period. HCV genotyping in the 5'-non-coding region (NCR) was performed in each center using the line probe assay (LiPA, in 63% of cases), sequencing (25%) or primer-specific polymerase chain reaction (PCR) (12%). HCV genotypes 1a, 1b, 2, 3, 4, 5, non-subtyped 1 and mixed infection were found in 18, 27, 9, 21, 9, 3, 11 and 1% of our population, respectively. HCV genotype distribution was associated with gender, age, source and duration of infection, alanine aminotransferase (ALT) levels, cirrhosis, alcohol consumption, hepatitis B virus (HBV) and human immunodeficiency virus (HIV) coinfection. In multivariate analysis, only the source of infection was the independent factor significantly associated with genotype (P = 0.0001). In conclusion, this study shows a changing pattern of HCV genotypes in France, with i.v. drug abuse as the major risk factor, an increase of genotype 4, and to a lesser extent 1a and 5, and a decrease of genotypes 1b and 2. The modification of the HCV genotype pattern in France in the next 10 years may require new therapeutic strategies, and further survey studies.

The influence of orthognathic surgery on masticatory performance in retrognathic patients

Surgical correction of retrognathism may influence chewing performance and its underlying mechanisms selection and breakage of food particles. In this study we examined the hypothesis that treatment of this anomaly improves chewing performance. Furthermore, we determined to what extent this change can be attributed to selection and breakage of food particles. Eleven patients were tested before and 1-1.5 years after surgery. To determine chewing performance, eight cubes of 8 mm of a silicone rubber (Optosil) were used as a test food. Selection and breakage were determined in one-chew experiments using three particle sizes. On average, no differences were found for chewing performance, selection or breakage. However, on an individual basis, patients with a poor chewing performance before surgery tended to improve, whereas no improvement was observed for patients with a good chewing performance. The change in chewing performance was mainly due to a change in breakage of the food particles.

Random outcomes of allergen-specific responses in atopic families

BACKGROUND

Allergens are common non-infectious antigens to which people will mount T cell dependent humoral responses. Among genetically susceptible individuals, an antigen-specific response results involving the production of allergen-specific IgE (atopy).

OBJECTIVE

Determine if this susceptibility is manifested as an inherited, allergen-specific trait or a random response to allergens among susceptible people.

METHODS

We evaluated allergen-specific outcomes in 1099 members of families with positive atopic history (26 multi-generation and 112 nuclear families). Each was tested for sensitivity to 14 common allergens by standardized skin prick test (SPT), a marker of specific IgE production. Over 15,000 individual SPT's were evaluated. Among five randomly selected multi-generation families (N=163), semi-quantitative determinations of Amb a 1-specific IgA1,2 and IgG1-4 were determined in three groups: (A) Amb a SPT(+)/Amb a 1-IgE(+), (B) Amb a SPT(-)/Amb a 1-IgE(+), (C) Amb a SPT(-)/Amb a 1-IgE(-).

RESULTS

By rank correlation statistics, there were no discernible 'patterns' of specific SPT outcomes among any of the multi-generation families, suggesting that environmental exposure rather than allergen-specific inheritance determined the responses. This was confirmed among the nuclear families since the conditional SPT outcomes among children were independent of the SPT responses of their parents. Among five randomly selected multi-generation families, the relative proportionate concentrations of the Amb a 1-specific IgA and IgG subclasses were comparable, regardless of atopic sensitization to the ragweed allergen Amb a.

CONCLUSION

While the general propensity for atopy may be inherited, an individual's specific atopic outcome is a random variable independent of familial sensitization patterns.

The use of an oral fluid immunoglobulin G ELISA for the detection of Helicobacter pylori infection in children

BACKGROUND

Enzyme linked immunosorbent assay (ELISA) evaluation of oral fluid immunoglobulin G (IgG) antibodies to Helicobacter pylori is a unique approach for both epidemiological studies and the diagnosis of infection, especially in children. The use of oral fluid sampling to evaluate specific H. pylori IgG antibodies has advantages over serum, including reduced biohazard risk and noninvasive collection. Oral fluid sampling is fast and involves minimal patient discomfort. Since children facilitate transmission of H. pylori infection, a simple, accurate, noninvasive diagnostic test is necessary for large epidemiologic studies. The aim of our study was to evaluate a new oral fluid ELISA for detection of IgG antibodies to H. pylori in children.

MATERIALS AND METHODS

We compared this new oral fluid ELISA with the HM-CAPTM serum ELISA and gastric biopsy histology using 779 oral fluid samples from children collected at 11 clinical sites across the United States. This cohort included 315 children symptomatic for abdominal pain and 464 asymptomatic. All samples were evaluated in a double blind manner. The oral fluid ELISA demonstrated a sensitivity of 76.2% and a specificity of 94.0% in children 2 months old to 201/2 years, as compared with the HM-CAPTM serologic assay. The assay's sensitivity improved to 81.3% in children aged 5 or greater and the specificity remained at 94.0%. When compared with gastric biopsy histology in the same age group, the oral fluid ELISA demonstrated a sensitivity of 71.7% and a specificity of 90.4%.

RESULTS

This new oral fluid ELISA is moderately sensitive and offers a very specific method for detecting H. pylori infection in older children, but it is of little value in children under the age of 5 years.

CONCLUSIONS

Overall, we conclude that this oral fluid ELISA does not appear to be a helpful clinical tool for the diagnosis of H. pylori infection in children.

Evidence of an affinity threshold for IgE-allergen binding in the percutaneous skin test reaction

BACKGROUND

Atopy is an aberrant immune response involving allergen-specific IgE production, though serum IgE concentration is not an entirely reliable diagnostic tool, particularly for epidemiological and genetic studies. There is no clear correlation between IgE and other indicators of atopy such as skin prick tests (SPT)s, and physiological associations are difficult to justify in cases with detectable IgE but negative SPT results.

OBJECTIVE

IgE reflects the number of molecules available to produce an atopic response, but the degree of the response is determined by the binding strength (affinity) between receptor-bound IgE and the allergen. We sought to determine if there was an association between binding affinity and SPT results in people with histories of atopy.

METHODS

Standard SPTs (whole allergen extracts) were administered to people with histories of sensitivities to ragweed and house dust mite. The concentrations and affinities of serum allergen-specific IgEs were determined using the purified allergens Amb a 1 and Der p 1.

RESULTS

There was a positive correlation between weal area and allergen-specific IgE among SPT-positive donors. However, for those individuals with detectable amounts of allergen-specific IgE, there was considerable overlap of IgE values between SPT-positive and -negative groups. Among sensitized donors, IgE-allergen interactions were characterized by two or three specific reactions of very high affinity (K(A) range 10(8) -10(11) M). Negative SPT reactions were associated with lowered IgE binding affinities to major allergens. This delimited two groups with atopic disorders: specific IgE(+)/ SPT(+) and specific IgE(+)/SPT(-).

CONCLUSION

The product of antibody affinity and concentration, which we define as antibody capacity (CAP = K(A) x IgE), is more informative with regard to describing allergen sensitivity than antibody concentration alone. Antibody binding capacity provides physiological evidence of atopy in some subjects who do not test positively by common methods and suggests an affinity threshold to produce a positive SPT reaction.

The outbreak of West Nile virus infection in the New York City area in 1999

BACKGROUND

In late August 1999, an unusual cluster of cases of meningoencephalitis associated with muscle weakness was reported to the New York City Department of Health. The initial epidemiologic and environmental investigations suggested an arboviral cause.

METHODS

Active surveillance was implemented to identify patients hospitalized with viral encephalitis and meningitis. Cerebrospinal fluid, serum, and tissue specimens from patients with suspected cases underwent serologic and viral testing for evidence of arboviral infection.

RESULTS

Outbreak surveillance identified 59 patients who were hospitalized with West Nile virus infection in the New York City area during August and September of 1999. The median age of these patients was 71 years (range, 5 to 95). The overall attack rate of clinical West Nile virus infection was at least 6.5 cases per million population, and it increased sharply with age. Most of the patients (63 percent) had clinical signs of encephalitis; seven patients died (12 percent). Muscle weakness was documented in 27 percent of the patients and flaccid paralysis in 10 percent; in all of the latter, nerve conduction studies indicated an axonal polyneuropathy in 14 percent. An age of 75 years or older was an independent risk factor for death (relative risk adjusted for the presence or absence of diabetes mellitus, 8.5; 95 percent confidence interval, 1.2 to 59.1), as was the presence of diabetes mellitus (age-adjusted relative risk, 5.1; 95 percent confidence interval, 1.5 to 17.3).

CONCLUSIONS

This outbreak of West Nile meningoencephalitis in the New York City metropolitan area represents the first time this virus has been detected in the Western Hemisphere. Given the subsequent rapid spread of the virus, physicians along the eastern seaboard of the United States should consider West Nile virus infection in the differential diagnosis of encephalitis and viral meningitis during the summer months, especially in older patients and in those with muscle weakness.

Echocardiographic outcome of infants treated as newborns with inhaled nitric oxide for severe hypoxemic respiratory failure

OBJECTIVE

To determine the cardiovascular outcome of a group of term newborns treated with inhaled nitric oxide (iNO) for severe hypoxemic respiratory failure with associated persistent pulmonary hypertension.

STUDY DESIGN

We performed echocardiographic evaluations in 40 survivors treated for severe neonatal hypoxemic respiratory failure. Each of the 40 had at least 2 follow-up echocardiograms at 3 or 6 and 24 months. These studies were compared with echocardiograms done in infants in a normal, age-matched control group.

RESULTS

Three of 31 infants met echocardiographic criteria for pulmonary hypertension at the 3-month examination. Two of the 3 had associated structural heart disease (1 with an atrial septal defect and 1 with a ventricular septal defect). At 24 months only 1 patient had pulmonary hypertension. This infant had an atrial septal defect that was surgically closed shortly after the 24-month echocardiogram because of the pulmonary hypertension. Group comparisons of 3- and 24-month echocardiographic variables showed no differences between the study and control groups. In the 31 infants in whom serial studies were completed, expected age-related changes were demonstrated between the 3- and 24-month examinations.

CONCLUSIONS

The incidence of residual pulmonary hypertension in infants treated as newborns for severe hypoxemic respiratory failure is low. The group at highest risk is those with structural heart disease.

Prevalence of ocular hemorrhage in patients receiving warfarin therapy

BACKGROUND

Warfarin, the drug most commonly used for outpatient anticoagulation therapy, has bleeding as its main side effect. The objective of this study was to determine the prevalence of ocular hemorrhage in patients receiving warfarin and to compare it to the prevalence in the general population.

METHODS

Patients receiving warfarin therapy who were attending the anticoagulation clinic at a tertiary care hospital in Montreal between October and December 1996 received a flyer inviting them to have their eyes examined to look for "ocular bleeding." Consenting patients were examined for subconjunctival hemorrhage, gross hyphema, and vitreous and retinal hemorrhages through external ocular examination and funduscopic examination with the pupils dilated using direct and indirect ophthalmoscopy.

RESULTS

Of the 1225 patients seen at the clinic 126 (10%) agreed to participate. Four patients (3%) were found to have intraretinal hemorrhage at the time of examination. All hemorrhages were visually insignificant.

INTERPRETATION

The risk of retinal hemorrhage in patients without preexisting ocular disease, such as retinal neovascularization or choroidal vasculopathy, who are receiving warfarin therapy is so small that it should not deter physicians from prescribing this drug when indicated.

Characterization of polyclonal allergen-specific IgE responses by affinity distributions

Polyclonal IgE responses have been previously characterized by allergen-specific antibody levels and by identification of amino acid sequences related to immunodominant epitopes. However, the binding affinities related to these antibody families are not well known. Using sera from donors with known sensitivities to ragweed or house dust mite allergens, we studied the binding reactions between the purified allergens Amb a 1 and Der p 1 and allergen-specific IgE's by determining affinity distribution functions. The distributions of binding affinities only exhibited a few dominant reactions indicated by peaks in an affinity distribution display. In all the donors tested, there were two dominant peaks and in 2/3 of the cases there was a third peak for both Amb a 1 and Der p 1. We further characterized the polyclonal interactions between IgE and Der p 1 by inhibiting the specific binding of IgE using peptide fragments known to be constituents of Der p 1 epitopes. Each peptide inhibited only a single peak in the affinity distributions. It would appear that the peaks in the affinity distribution represent antibodies directed to single epitopes. These results suggest that in our atopic population the response is surprisingly uniform. The bulk of the IgE response (70-80%) is of high affinity (10(8)-10(11) M(-1)) and directed towards a few epitopes. The relative affinities towards epitopes seem to be determined by the structure of the epitope and not variations of individuals' immune responses.