Short-term risk prediction after major lower limb amputation: PERCEIVE study

BACKGROUND

The accuracy with which healthcare professionals (HCPs) and risk prediction tools predict outcomes after major lower limb amputation (MLLA) is uncertain. The aim of this study was to evaluate the accuracy of predicting short-term (30 days after MLLA) mortality, morbidity, and revisional surgery.

METHODS

The PERCEIVE (PrEdiction of Risk and Communication of outcomE following major lower limb amputation: a collaboratIVE) study was launched on 1 October 2020. It was an international multicentre study, including adults undergoing MLLA for complications of peripheral arterial disease and/or diabetes. Preoperative predictions of 30-day mortality, morbidity, and MLLA revision by surgeons and anaesthetists were recorded. Probabilities from relevant risk prediction tools were calculated. Evaluation of accuracy included measures of discrimination, calibration, and overall performance.

RESULTS

Some 537 patients were included. HCPs had acceptable discrimination in predicting mortality (931 predictions; C-statistic 0.758) and MLLA revision (565 predictions; C-statistic 0.756), but were poor at predicting morbidity (980 predictions; C-statistic 0.616). They overpredicted the risk of all outcomes. All except three risk prediction tools had worse discrimination than HCPs for predicting mortality (C-statistics 0.789, 0.774, and 0.773); two of these significantly overestimated the risk compared with HCPs. SORT version 2 (the only tool incorporating HCP predictions) demonstrated better calibration and overall performance (Brier score 0.082) than HCPs. Tools predicting morbidity and MLLA revision had poor discrimination (C-statistics 0.520 and 0.679).

CONCLUSION

Clinicians predicted mortality and MLLA revision well, but predicted morbidity poorly. They overestimated the risk of mortality, morbidity, and MLLA revision. Most short-term risk prediction tools had poorer discrimination or calibration than HCPs. The best method of predicting mortality was a statistical tool that incorporated HCP estimation.

P–138 When is low quality really low? Should we transfer low-grade blastocysts?

Study question

What is the live birth rate after single, low-grade blastocyst (LGB) transfer?

Summary answer

The live birth rate for LGBs is 28%, ranging between 15–31% for the different inner cell mass (ICM) and trophectoderm (TE) subgroups of LGBs.

What is known already

Live birth rates following LGB transfer are varied and have been reported to be in the range of 5–39%. However, these estimates are inaccurate as studies investigating live birth rates following LGB transfer are inherently limited by sample size (n = 10–440 for LGB transfers) due to LGBs being ranked last for transfer. Further, these studies are heterogenous with varied LGB definitions and design. Collating LGB live birth data from multiple clinics is warranted to obtain sufficient numbers of LGB transfers to establish reliable live birth rates, and to allow for delineation of different LGB subgroups, including blastocyst age and female age.

Study design, size, duration

We performed a multicentre, multinational retrospective cohort study in 9 IVF centres in China and New Zealand from 2012 to 2019. We studied the outcome of 6966 single blastocyst transfer cycles on days 5–7 (fresh and frozen) according to blastocyst grade, including 875 transfers from LGBs (<3bb, this being the threshold typically applied to LGB studies). Blastocysts with expansion stage 1 or 2 (early blastocysts) were excluded.

Participants/materials, setting, methods

The main outcome measured was live birth rate. Blastocysts were grouped according to quality grade: good-grade blastocysts (GGBs; n = 3849, aa, ab and ba), moderate-grade blastocysts (MGBs; n = 2242, bb) and LGBs (n = 875, ac, ca, bc, cb and cc) and live birth rates compared using the Pearson Chi-squared test. A logistic regression analysis explored the relationship between blastocyst grade and live birth after adjustment for the confounders: clinic, female age, expansion stage, and blastocyst age.

Main results and the role of chance

The live birth rates for GGBs, MGBs and LGBs were 45%, 36% and 28% respectively (p < 0.0001). Within the LGB group, the highest live birth rates were for grade c TE (30%) and the lowest were for grade c ICM (19%). The lowest combined grade (cc) maintained a 15% live birth rate (n = 7/48). After accounting for confounding factors, including female age and blastocyst characteristics, the odds of live birth were 2.33 (95% CI = 1.88–2.89) for GGBs compared to LGBs and 1.56 (95% CI = 1.28–1.92) for MGBs compared to LGBs following fresh and frozen blastocyst transfers (p < 0.0001, odds ratios confirmed in exclusively frozen blastocyst transfer cycles). When stratified by individual ICM and TE grade, the odds of live birth according to ICM grade were 1.31 (a versus b; 95% CI = 1.15–1.48), 2.82 (a versus c; 95% CI = 1.91–4.18) and 2.16 (b versus c; 95% CI = 1.48–3.16; all p < 0.0001). The odds of live birth according to TE grade were 1.33 (a versus b; 95% CI = 1.17–1.50, p < 0.0001), 1.85 (a versus c; 95% CI = 1.45–2.34, p < 0.0001) and 1.39 (b versus c; 95% CI = 1.12–1.73, p = 0.0024).

Limitations, reasons for caution

Despite the large multicentre design of the study, analyses of transfers occurring within the smallest subsets of the LGB group were limited by sample size. The study was not randomised and had a retrospective character.

Wider implications of the findings: LGBs maintain satisfactory live birth rates (averaging 28%) in the general IVF population. Even those in the lowest grading tier maintain modest live birth rates (15%; cc). It is recommended that LGBs not be universally discarded, and instead considered for subsequent frozen embryo transfer to maximize cumulative live birth rates.

Trial registration number

Not applicable

P–167 Assuring quality in embryology decision making: blastocyst grading agreement assessed via a smartphone application

Study question

Given the subjectivity of blastocyst grading and the challenge of performing routine competency assessments, how consistently do embryologists grade blastocysts when using an easily accessible phone application?

Summary answer

Grading agreement was fair to moderate for inner cell mass (ICM) and trophectoderm (TE), evidence that a mobile application can be used for quality assurance.

What is known already

Embryologists routinely perform external quality assessments (EQA), though the utility of EQA for quality improvement is limited, and more active, user-friendly tools are needed to improve quality assurance in embryology. Blastocyst grading is one of the most important and subjective tasks in clinical embryology, important for both blastocyst ranking and decision to freeze. Inter-user agreement is only fair for ICM (kappa 0.349) and TE grade (kappa 0.397; Storr et al., 2017). Fair agreement has also been reported for decision to freeze for a cohort of blastocysts that exhibited borderline morphology (kappa 0.301; Hammond et al., 2020).

Study design, size, duration

A prospective study of blastocyst grading consistency using ARTCompass, a mobile phone application designed to assess clinical decision making of laboratory staff for andrology and embryology competency. Two assessments, each with 100 images of expanded blastocysts in three planes, were performed by 42 embryologists from 9 clinics in 2 countries between April to July 2020. Survey 1 assessed ICM grading and survey 2 assessed TE grading using the same set of images for consistency.

Participants/materials, setting, methods

Blastocysts were of proportionally mixed grades (ranging from grade A to X) using a modified Gardner system that included “X” for non-viable ICM/TE. Embryologists were advised to complete the tests individually in one sitting. The Fleiss kappa coefficient (k) measured inter-rater agreement among embryologists when assigning blastocyst grade. Kappa value interpretation is as follows <0.20: poor; 0.21–0.40: fair; 0.41–0.60: moderate; 0.61–0.80: good and 0.81–1.00: very good.

Main results and the role of chance

Overall, agreement for ICM and TE grades was moderate among embryologists (kappa 0.47, 0.52, respectively). ICM grade B and C had the lowest agreement (0.37, 0.39), while ICM grade X (no, or degenerate ICM), and TE grade A showed the highest agreement (0.68, 0.62). These results illustrate that embryologists had difficultly classifying ICM grade when it was of moderate to poor quality (grade b or c), likely due to subjectivity in grading size and compaction level, but were good at classifying ICM grade when there was no apparent ICM (grade x). For TE grade, embryologists consistently identified a top-quality TE (grade a), which is reassuring as TE grade is the primary morphological feature used for blastocyst ranking. In general, this QA platform offers ease of use and shows agreement values for ICM and TE that are similar to other studies, suggesting that blastocyst grading with a mobile phone application is a viable option for quality assurance.

Limitations, reasons for caution

Only blastocyst grading was assessed, therefore additional competency assessments using a mobile device should be assessed for accuracy. Further studies are needed to determine if mobile applications can improve competency.

Wider implications of the findings: Ease of use by 42 embryologists indicates mobile applications may provide a user-friendly and accessible platform for QA. Since effective and efficient assessment of competency and KPIs is an ongoing challenge for laboratories, a mobile application is a novel and effective tool to monitor QA parameters in the IVF laboratory

Trial registration number

Not applicable

A multinational, prospective, observational study to estimate complete skin clearance in patients with moderate-to-severe plaque PSOriasis treated with BIOlogics in a REAL world setting (PSO-BIO-REAL)

Background

Anti‐tumour necrosis factor (TNF) and anti‐interleukin (IL)‐12/23 biologics revolutionized plaque psoriasis treatment by enabling ≥75% improvement in the Psoriasis Area and Severity Index (PASI 75) in clinical trials. Modern biologics are now reported to achieve PASI 100 (complete skin clearance) in clinical trials. However, real‐world evidence of skin clearance rates with biologics is limited. PSO‐BIO‐REAL was conducted to understand the real‐world burden of plaque psoriasis.

Objective

The primary objective of this observational study was to estimate the proportion of patients who achieved complete skin clearance at 6 months. Secondary objectives included maintenance of response and evaluation of complete skin clearance at 12 months.

Methods

PSO‐BIO‐REAL was a multinational, prospective, real‐world, non‐interventional study of skin clearance and patient‐reported outcomes (PROs) with biologics. A total of 846 patients from the United States (32%), France (28%), Italy (22%), the United Kingdom (11%) and Germany (8%) were enrolled and followed for one year. Eligible patients were aged ≥18 years with moderate‐to‐severe plaque psoriasis who had initiated a biologic for plaque psoriasis. Patients could be biologic‐naïve or switching biologics (biologic‐experienced). Assessments were made at baseline and at months 6 and 12.

Results

At 6 and 12 months, 23% and 26% of patients achieved complete skin clearance, respectively. Prior to study entry, 60% were biologic‐naïve. The proportion of patients achieving complete skin clearance was lower among biologic‐experienced patients (20% at both months 6 and 12) compared with biologic‐naïve patients (25% at month 6, 30% at month 12). The rate of complete skin clearance decreased as the number of prior biologics and baseline comorbidities increased.

Conclusion

Only one in four patients achieved complete skin clearance after 6 months of treatment with biologics. The study indicates there still is an unmet need for more efficacious biologics for patients with psoriasis.

Impact of advanced detector technology and iterative reconstruction on low-dose quantitative assessment of lung computed tomography density in a biological lung model

PURPOSE

Quantitative computed tomography (QCT)-derived measures of lung density are valued methods for objectively characterizing lung parenchymal and peripheral airways disease and are being used in a growing number of lung disease focused trials. Detector and reconstruction improvements in CT technology have allowed for significant radiation dose reduction in image acquisition with comparable qualitative image quality. We report the impact of detector type and reconstruction type on QCT lung density measures in relation to decreasing dose indices.

METHODS

Two sets of studies were completed in an in vivo pig model with a SOMATOM Definition Flash CT system: (a) prior to system upgrade with conventional detectors (UFC) and filtered back projection (FBP), and (b) post system upgrade with integrated electronic detectors (STELLAR) and iterative reconstruction (SAFIRE). CT data were acquired across estimated CT volume dose indices (CTDIvol ) ranging from 0.75 to 15 mGy at both inspiratory and expiratory breath holds. Semiautomated lung segmentations allowed calculation of histogram median, kurtosis, and 15th percentile. Percentage of voxels below -910 HU and -950 HU (inspiratory), and -856 HU (expiratory) were also examined. The changes in these QCT metrics from dose reduction (15 mGy down to 0.75 mGy) were calculated relative to paired reference values (15 mGy). Results were compared based on detector and reconstruction type.

RESULTS

In this study, STELLAR detectors improved concordance with 15 mGy values down to 3 mGy for inspiratory scans and 6 mGy for expiratory scans. The addition of SAFIRE reconstruction in all acquired measurements resulted in minimal deviation from reference values at 0.75 mGy.

CONCLUSION

The use of STELLAR integrated electronic detectors and SAFIRE iterative reconstruction may allow for comparable lung density measures with CT dose indices down to 0.75 mGy.

Association between 25-OH vitamin D and insulin is independent of lipoatrophy in HIV

OBJECTIVE

Vitamin D deficiency (VDD) is prevalent in HIV, and following antiretroviral therapy (ART), increased rates of lipoatrophy and metabolic abnormalities are described. We investigated the relationships between 25-hydroxyvitamin D [25(OH)D] and other metabolic parameters in a group of HIV patients with and without lipoatrophy to examine whether lipoatrophy could explain the high prevalence of VDD and metabolic abnormalities.

BACKGROUND

Vitamin D receptors are expressed in adipose tissue implicating vitamin D, through paracrine/autocrine mechanism, in exerting effects on fat metabolism. HIV patients frequently suffer from VDD, and those treated with thymidine analogues frequently suffer from lipoatrophy so we investigated whether lipoatrophy could explain these associations.

DESIGN AND PATIENTS

Cross-sectional study of HIV-infected male patients (n = 107; 39 with lipoatrophy) from the West Australian cohort with measurements of 25(OH)D, adiponectin, insulin, lipids and leg fat as a percentage of mass.

RESULTS

Reduced 25(OH)D levels were common and significantly associated with higher serum insulin in the entire cohort (P = 0·006), but there was no difference in 25(OH)D between untreated and antiretroviral-treated patients with or without lipoatrophy. Treated patients with lipoatrophy were more likely to take thymidine analogue therapy, were older and on therapy longer than treated patients without lipoatrophy. Adiponectin levels did not correlate with 25(OH)D, but lipoatrophic-treated patients had lower levels of adiponectin compared with nonlipoatrophic-treated patients.

CONCLUSIONS

Lower 25(OH)D is associated with higher serum insulin but not lipoatrophy or hypoadiponectinemia in HIV-infected patients. The association between VDD and insulin resistance is likely to be mediated by independent mechanisms.

PG545, a dual heparanase and angiogenesis inhibitor, induces potent anti-tumour and anti-metastatic efficacy in preclinical models

Background:

PG545 is a heparan sulfate (HS) mimetic that inhibits tumour angiogenesis by sequestering angiogenic growth factors in the extracellular matrix (ECM), thus limiting subsequent binding to receptors. Importantly, PG545 also inhibits heparanase, the only endoglycosidase which cleaves HS chains in the ECM. The aim of the study was to assess PG545 in various solid tumour and metastasis models.

Methods:

The anti-angiogenic, anti-tumour and anti-metastatic properties of PG545 were assessed using in vivo angiogenesis, solid tumour and metastasis models. Pharmacokinetic (PK) data were also generated in tumour-bearing mice to gain an understanding of optimal dosing schedules and regimens.

Results:

PG545 was shown to inhibit angiogenesis in vivo and induce anti-tumour or anti-metastatic effects in murine models of breast, prostate, liver, lung, colon, head and neck cancers and melanoma. Enhanced anti-tumour activity was also noted when used in combination with sorafenib in a liver cancer model. PK data revealed that the half-life of PG545 was relatively long, with pharmacologically relevant concentrations of radiolabeled PG545 observed in liver tumours.

Conclusion:

PG545 is a new anti-angiogenic clinical candidate for cancer therapy. The anti-metastatic property of PG545, likely due to the inhibition of heparanase, may prove to be a critical attribute as the compound enters phase I clinical trials.

Impact of Recording of Pre-Analytical Specimen Handling Conditions for ER and PR Testing in Women with Breast Cancer

Background: Hormone receptor testing is important in the management of women with breast cancer. We previously reported potential adverse effects of variable specimen and prolonged specimen handling conditions on ER (estrogen receptor) test results (2005 SABCS, abstract#5107).Objective: To compare prevalence of ER and PR (progesterone receptor) negative test results following standardization of pre-analytical specimen handling conditions at Intermountain facilities.Methods: Prospective, quasi-experimental study design of 6 Intermountain facilities. Facilities were separated into 2 categories: experimental (2 facilities) and control (4 facilities) groups. Pre-analytical specimen handling conditions (including recording of time to fixative and duration of fixation in neutral buffered formalin) were standardized at experimental facilities but not at control facilities. Standardization consisted of educating operating and grossing room staff about appropriate specimen handling and the value of recording time to fixation and fixative duration as a way to improve pre-analytic standardization. OR staff was called in any cases where times were not recorded. Study population includes women undergoing breast cancer surgery and who were tested for ER/PR status between January 2008 and January 2009. Specimen handling conditions and ER/PR test results were collected manually. Covariates were retrieved from cancer registry and included age, grade, positive lymph nodes, specimen type, and tumor stage. Multivariate logistic regression was used to compare prevalence of ER and PR negativity between experimental and control facilities after controlling for covariates.Results: 1054 women with breast cancer were tested for ER/PR status during the study period. The average age was 60.2 years (59.2 years for control cases and 61.1 years for the experimental group). The overall prevalence of ER and PR negative tests was respectively 18.5% and 27.3%. Average time to fixative at experimental facilities was 18.4 minutes (SE=3.1; 95% CI, 12.2-25.6) and average time in fixative was 18.0 hours (SE=0.4; 95% CI, 17.2-18.8). Compared to experimental facilities, both the prevalence of ER and PR negativity was higher (16.9% vs 19.7%) and (23.9% vs 30.0%) at control facilities. After controlling for covariates there was no difference in prevalence of ER negativity (p=0.13) between the two groups. However, the prevalence of PR negativity remains significantly higher (p<0.01) at control facilities compared to experimental facilities even after controlling for covariates.Conclusions: The prevalence of ER and PR negative results was lower following staff education and recording of pre-analytical specimen handling conditions. Our data suggest that staff education and recording of pre-analytical specimen handling conditions has the potential to optimize hormone receptor test results. It also shows the feasibility of fixing tissue routinely after less than an hour interval between time of breast cancer tissue removal and fixation and underscores the value of standardization of pre-analytic handling as a method to improve ER and PR testing on breast cancer specimens.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4154.

HLA-B*5701 typing: evaluation of an allele-specific polymerase chain reaction melting assay

Inheritance of HLA-B*5701 is a strong predictor of a hypersensitivity reaction to the anti-HIV drug abacavir. The identification of susceptible individuals prior to the institution of abacavir therapy is therefore of clinical importance and has generated demand for a simple and rapid diagnostic test for carriage of HLA-B*5701. In this study, we describe the development of such a method based on allele-specific polymerase chain reaction (AS-PCR) and melting curve analysis. Ninety-six patient samples including 36 HLA-B*5701-positive samples and 60 HLA-B*5701-negative samples were analysed. Compared with sequence-based typing, this method had 100% sensitivity and specificity for the HLA-B*5701 allele. In conclusion, the AS-PCR/melting curve approach minimises post-polymerase chain reaction handling processing and provides an attractive alternative to currently described AS-PCR methods.

Viral gastroenteritis - a danger to the patient, a danger to the staff

Viral gastroenteritis is usually a mild, self-limiting illness. We report a case of a previously well 74-year-old woman who suffered a grave complication of this common condition, and caused a significant outbreak of illness amongst staff involved in her care. This case highlights the risks of Hospital Acquired Infection and raises important infection control issues. It illustrates the hazards associated with exposure to potentially infectious secretions and presents a clear message to medical and nursing staff involved in the care of the acute surgical emergency.

P105 as a prognostic indicator in patients irradiated for locally advanced head-and-neck cancer: a clinical/laboratory correlative analysis of RTOG-9003

PURPOSE

In a previous retrospective study, p105 AD, a proliferation-associated nuclear antigen density (AD), was found to be an independent prognostic factor for patients irradiated for locally advanced head-and-neck cancer. We sought to confirm this finding by analyzing patients entered on RTOG 9003, a Phase III randomized trial of altered fractionation radiotherapy.

METHODS AND MATERIALS

Paraffin blocks of pretreatment biopsies of the primary tumor of patients with Stage III or IV squamous cell carcinoma of the oral cavity, oropharynx, or supraglottic larynx, or Stage II squamous cell carcinoma of the hypopharynx or base of tongue entered on RTOG 9003 were prospectively collected at patient entry. From these paraffin blocks, areas of tumor were selected based on histologic examinations and sectioned. Nuclear suspensions were then prepared and processed for p105 antibody and DNA staining. Flow cytometric quantification of p105 labeling indices and DNA content were then performed for correlation with local-regional control and survival.

RESULTS

Paraffin blocks of tumor biopsies from 457 of 1073 patients entered were available for p105 determination. There was no significant difference in pretreatment characteristics between patients who had paraffin blocks available or not available. The median (range) of p105 labeling index (LI-C), p105 labeling index of cells in S phase (p105 LI-S), and p105 AD were 56 (range: 6-99), 8.255 (range: 0.913-23), and 67 (range: 5-364), respectively. Multivariate analysis of prognostic factors showed that T stage, N stage, Karnofsky performance status, and fractionation schedule were significant for local-regional control (p < 0.0001, 0.0011, <0.0001, and 0.007, respectively) and T stage, N stage, Karnofsky performance status, and tumor grade were significant for survival (p = 0.018, 0.002, <0.0001, and 0.0058, respectively). Neither p105 LI-C nor p105 LI-S nor p105 AD nor DNA ploidy was significant for local-regional control or survival.

CONCLUSION

p105 labeling indices, antigen density, and DNA ploidy do not predict the outcome of patients irradiated for advanced squamous cell carcinomas of the head and neck.

Loss of p16 expression is of prognostic significance in locally advanced prostate cancer: an analysis from the Radiation Therapy Oncology Group protocol 86-10

PURPOSE

The retinoblastoma (RB) cell cycle regulatory pathway is known to be deregulated in virtually all known human tumors. The protein product of the RB gene, pRB, and its upstream regulator, p16, are among the most commonly affected members of this pathway. We investigated the prognostic significance of both pRB and p16 expression in locally advanced prostate cancers, from patients treated on the Radiation Therapy Oncology Group (RTOG) protocol 86-10.

MATERIALS AND METHODS

Sixty-seven cases from RTOG 86-10 had immunohistochemically stained slides, judged interpretable for both p16 and pRB, available for analysis. Median follow-up was 8.9 years (range, 6.0 to 11.8 years) for surviving patients. Staining for each marker was then correlated with overall survival, local progression, distant metastasis, and disease-specific survival.

RESULTS

Loss of p16 expression, as defined by expression was significantly associated with reduced overall survival (P =.039), disease-specific survival (P =.006), and higher risk of local progression (P =.0007) and distant metastasis (P =.026) in the univariate analysis. In the multivariate analysis, loss of p16 was significantly associated with reduced disease-specific survival (P =.0078) and increased risk of local failure (P =.0035) and distant metastasis (P =.026). A borderline association with reduced overall survival (P =.07) was also evident. Loss of pRB was associated with improved disease-specific survival on univariate (P =.028) and multivariate analysis (P =.043), but carried no other significant outcome associations.

CONCLUSION

Loss of p16 is significantly associated with adverse clinical outcome in cases of locally advanced prostate cancer.

Regulation of p53 by hypoxia: dissociation of transcriptional repression and apoptosis from p53-dependent transactivation

Hypoxic stress, like DNA damage, induces p53 protein accumulation and p53-dependent apoptosis in oncogenically transformed cells. Unlike DNA damage, hypoxia does not induce p53-dependent cell cycle arrest, suggesting that p53 activity is differentially regulated by these two stresses. Here we report that hypoxia induces p53 protein accumulation, but in contrast to DNA damage, hypoxia fails to induce endogenous downstream p53 effector mRNAs and proteins. Hypoxia does not inhibit the induction of p53 target genes by ionizing radiation, indicating that p53-dependent transactivation requires a DNA damage-inducible signal that is lacking under hypoxic treatment alone. At the molecular level, DNA damage induces the interaction of p53 with the transcriptional activator p300 as well as with the transcriptional corepressor mSin3A. In contrast, hypoxia primarily induces an interaction of p53 with mSin3A, but not with p300. Pretreatment of cells with an inhibitor of histone deacetylases that relieves transcriptional repression resulted in a significant reduction of p53-dependent transrepression and hypoxia-induced apoptosis. These results led us to propose a model in which different cellular pools of p53 can modulate transcriptional activity through interactions with transcriptional coactivators or corepressors. Genotoxic stress induces both kinds of interactions, whereas stresses that lack a DNA damage component as exemplified by hypoxia primarily induce interaction with corepressors. However, inhibition of either type of interaction can result in diminished apoptotic activity.

Age- and gender-related elastin distribution changes in human vocal folds

The composition of the lamina propria in human vocal folds has been shown to affect vocal performance. Elastin plays a significant role in the biomechanical effects of the lamina propria. We obtained 19 larynges from the state medical examiner from subjects whose cause of death was unrelated to the trachea and laryngeal regions. The sample contained male and female subjects in the infant, adult, and geriatric age groups. We stained the vocal folds for elastin with Verhoeff's elastic tissue stain and studied them with use of an image analysis system configured for light microscopy. Distributions of elastin were measured from superficial to deep within the lamina propria (from epithelium to vocal muscle). These elastin distributions were then compared with the use of statistical software. The data showed that there was an increase in elastin content from the infant through geriatric stages. No gender-related differences were found. Infant folds had about 23% of the elastin found in adults, and geriatric subjects had about 879% of the elastin found in adults. Both of these results were statistically significant (p < 0.05). The distributions were consistent with previous observations that the lamina propria is a layered structure with most of the elastin present in the intermediate layer. This layer was larger in geriatric subjects than in adult and pediatric subjects. We observed that the fiber diameter appeared to be larger in geriatric subjects (this observation is currently being verified with electron microscopy) whereas smaller, spiraled fibers appeared in pediatric subjects.

Analysis of cellular location and concentration in vocal fold lamina propria

Studies have shown that the lamina propria plays an important role in voice production. Recent studies have analyzed the presence of different proteins and quantified their extent in the lamina propria, but no similar study has yet been done on cellular makeup. The distribution of three different cell types in the lamina propria of 22 human vocal folds was studied. These types are fibroblasts, macrophages, and myofibroblasts. The roles of these cells in the extracellular matrix are described. Their distribution was quantified with use of an image-analysis system. We arbitrarily divided the lamina propria into five sections (each representing 20% of the lamina propria) and compared cell numbers among these sections. Gender comparisons were also made. From these studies it is evident that the cellular distribution in the lamina propria is not uniform. Fibroblasts were more abundant in the deepest 20% of the lamina propria (p < 0.008), myofibroblasts were more abundant in the most superficial 20% (p < 0.016), and in the 36% of our samples that contained macrophages in the lamina propria, there was a significantly higher number of macrophages in the first 20% of the lamina propria (p < 0.003). The only significant gender difference was that women had twice as many macrophages in the most superficial 20% of the lamina propria as men (p < 0.05). The higher myofibroblast activity in the first 20% could indicate that the superficial layer is a region of constant repair. The increased number of macrophages in the superficial layer likely indicates an inflammatory response to inhalants (because of the role of macrophages in the inflammatory response and the fact that only 36% of the patients showed any macrophage activity at all).

Apoptosis-specific protein (ASP) identified in apoptotic Xenopus thymus tumor cells

A novel apoptosis-specific protein (ASP) has recently been identified in the cytoplasm of apoptotic mammalian cells. This paper investigates whether ASP is found in Xenopus thymus tumor-derived lymphoid cell lines undergoing apoptosis and also in apoptotic, nontransformed splenocytes. Cultured Xenopus tumor lymphoid cells induced to undergo apoptosis by serum deprivation or treatment with the calcium ionophore, ionomycin, displayed altered morphology typical of apoptotic cells, as judged by flow cytometric light-scatter characteristics and by fluorescence microscopy of acridine-orange-stained cells. Flow cytometry of permeabilized cells and fluorescence microscopy of acetone-fixed cytospins revealed that apoptotic Xenopus tumor cells, especially those displaying loss or condensation of DNA, displayed increased expression of epitopes recognized by a rabbit polyclonal antibody against ASP. Flow cytometry confirmed that ASP is also expressed in splenocytes induced to apoptose by culture in ionomycin or following concanavalin A stimulation. No increased expression of ASP was seen when lymphoid tumor cells or splenocytes were induced into necrosis by overdose with the antifungal agent amphotericin B. Western blotting with antibody against ASP identified the emergence of several protein bands in cell lysates from apoptotic, but not necrotic, Xenopus tumor cells. The new and simple methodology for identifying apoptotic cells described here is likely to be of value to those studying immune system development and associated programmed cell death in Xenopus.