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Cost/variance optimization for human exposure assessment studies.

The National Human Exposure Assessment Survey (NHEXAS) field study in EPA Region V (one of three NHEXAS field studies) provides extensive exposure data on a representative sample of 249 residents of the Great Lakes states. Concentration data were obtained for both metals and volatile organic compounds (VOCs) from multiple environmental media and from human biomarkers. A variance model for the logarithms of concentration measurements is used to define intraclass correlations between observations within primary sampling units (PSUs) (nominally counties) and within secondary sampling units (SSUs) (nominally Census blocks). A model for the total cost of the study is developed in terms of fixed costs and variable costs per PSU, SSU, and participant. Intraclass correlations are estimated for media and analytes with sufficient sample sizes. We demonstrate how the intraclass correlations and variable cost components can be used to determine the sample allocation that minimizes cost while achieving pre-specified precision constraints for future studies that monitor environmental concentrations and human exposures for metals and VOCs.

Biomarkers↗

Differential induction of CYP1A1 in duodenum, liver and kidney of rats after oral intake of soil containing polycyclic aromatic hydrocarbons.

We have analyzed the induction of the cytochrome P450 enzyme CYP1A1 as a biomarker of effect in duodenum, liver and kidney of rats after oral intake of contaminated soil particles. The soil samples originated from industrial sites and were contaminated with polycyclic aromatic hydrocarbons (PAH) to variable extents, ranging from 60 to 4700 mg PAH/kg soil. Soil samples were administered for one week as a mixture with commercial rodent diets. After exposure, microsomes of several organs were prepared and analyzed for CYP1A1, enzymatically and by Western blots. All contaminated soils led to induction of CYP1A1 in duodenal mucosa cells, regardless of their extent of contamination, showing that relevant doses were mobilized in the gastrointestinal tract and adsorbed. Subsequent distribution of non-metabolized compounds is indicated by induction of CYP1A1 in the liver. However, some samples did not lead to a response in the liver, due to their quantitative and qualitative contaminant composition. In accordance with previous results, there is a sigmoidal dose-response relationship between induction of hepatic CYP1A1 levels and the soil contamination with higher condensates of PAH. In contrast, the response in the duodenum appeared to be hyperbolic and correlated well with the amounts of total PAH. Highly contaminated soil, being nearly devoid of higher condensates of PAH, led to pronounced induction in the duodenum but failed to induce CYP1A1 in the liver. Successful passage of contaminants through the intestinal barrier and the liver compartment is shown by increased CYP1A1 expression in the kidney. Compared with enzyme levels induced in the liver, those of the kidney are much lower and amount to only about 1/20 of the liver values for soils with high induction potential. Hence, oral PAH intake leads to differential induction patterns of CYP1A1 in duodenum, liver and kidney of rats. The observations raise questions concerning the role of the primary duodenal PAH metabolism in preventing contaminant-dependent hazardous effects, and of the significance of differential CYP1A1 expressions for carcinogenic processes in several tissues.

Animals↗

The use of fatty acid biomarkers to reflect dietary intake.

PURPOSE OF REVIEW: This review compares fatty acid biomarkers to assess compliance in dietary intervention trials with their application in epidemiological studies. RECENT FINDINGS: Although many studies have used fatty acid biomarkers to assess compliance in short-term dietary intervention trials and habitual diets in observational studies, there is little information on the reliability and comparability of these measures. In this review, we summarize the usefulness and limitations of fatty acid biomarkers in clinical and epidemiological studies. As there are very few recent publications in this area, a complete literature review is provided. SUMMARY: Several options are available for the biological assessment of dietary fatty acids. The type of study (short or long-term), the metabolic characteristics and expected variability in the fatty acids of interest are major considerations when determining which tissues reflect a better measure of true intake. Certain fatty acids may not be suitable to assess differences in intake under non-isocaloric conditions and when trying to identify small differences. Serum cholesterol ester is the most suitable serum fraction to assess short-term dietary compliance, but given the multiple factors that affect response, the quantification of compliance should be interpreted with caution. Adipose tissue is the biomarker of choice for long-term intake, but a preferred blood constituent (plasma versus erythrocytes) is difficult to establish given the data available to date. Future studies should explore the use of whole blood as an alternative choice to measure fatty acid intake in epidemiological studies.

Biomarkers↗

Urinary kidney injury molecule-1: a sensitive quantitative biomarker for early detection of kidney tubular injury.

Sensitive and specific biomarkers are needed to detect early kidney injury. The objective of the present work was to develop a sensitive quantitative urinary test to identify renal injury in the rodent to facilitate early assessment of pathophysiological influences and drug toxicity. Two mouse monoclonal antibodies were made against the purified ectodomain of kidney injury molecule-1 (Kim-1), and these were used to construct a sandwich Kim-1 ELISA. The assay range of this ELISA was 50 pg/ml to 5 ng/ml, with inter- and intra-assay variability of <10%. Urine samples were collected from rats treated with one of three doses of cisplatin (2.5, 5, or 7.5 mg/kg). At one day after each of the doses, there was an approximately three- to fivefold increase in the urine Kim-1 ectodomain, whereas other routinely used biomarkers measured in this study [plasma creatinine, blood urea nitrogen (BUN), urinary N-acetyl-beta-glucosaminidase (NAG), glycosuria, proteinuria] lacked the sensitivity to show any sign of renal damage at this time point. When rats were subjected to increasing periods (10, 20, 30, or 45 min) of bilateral ischemia, there was an increasing amount of urinary Kim-1 detected. After only 10 min of bilateral ischemia, Kim-1 levels on day 1 were 10-fold higher (5 ng/ml) than control levels, whereas plasma creatinine and BUN were not increased and there was no glycosuria, increased proteinuria, or increased urinary NAG levels. Thus urinary Kim-1 levels serve as a noninvasive, rapid, sensitive, reproducible, and potentially high-throughput method to detect early kidney injury in pathophysiological studies and in preclinical drug development studies for risk-benefit profiling of pharmaceutical agents.

Animals↗

Development of novel cell surface CD34-targeted recombinant adenoassociated virus vectors for gene therapy.

Recombinant adenoassociated virus (rAAV) type 2 vectors have been used to transduce a wide variety of cell types, including hematopoietic progenitor cells. For in vivo gene transfer, it is desirable to have an rAAV vector that specifically transduces selected target cells. As a first step toward generating an rAAV vector capable of targeting delivery in vivo, we have engineered a chimeric protein combining the AAV capsid protein and the variable region of a single-chain antibody against human CD34 molecules, a cell surface marker for hematopoietic stem/progenitor cells. Inclusion of the chimeric CD34 single-chain antibody-AAV capsid proteins within an rAAV virion significantly increased the preferential infectivity of rAAV for the CD34+ human myoleukemia cell line KG-1, which is normally refractory to rAAV transduction. Antibodies against the single-chain antibody and the CD34 protein blocked this transduction. This chimeric vector represents a significant improvement in the host range of rAAV and the first step toward specific gene delivery by rAAV vectors to cells of choice, in this case, hematopoietic progenitor cells, for the treatment of human disease.

Antibodies, Anti-Idiotypic↗

Bull sperm head morphometry related to abnormal chromatin structure and fertility.

This study investigated the relationship between morphologically abnormal sperm, sperm chromatin structure, and fertility. Semen samples were obtained from 13 bulls. The sperm chromatin structure assay (SCSA), a sensitive measure of denaturability of sperm nuclear DNA in situ following acid treatment, was performed on each sample to quantitate abnormal chromatin structure. Feulgenstained sperm head morphology was measured by computerized image analysis (ONCOR-Image): Sixteen parameters were measured for each of 200 nuclei per sample. Fertility estimates were available for nine of the bulls. The SCSA variable SD alpha t was correlated with fertility ranking (r = 0.617, P < 0.01). No correlations were seen between means of the imaging variables and SCSA variables % COMP alpha t or SD alpha t. Significant correlations (P < 0.05) were seen between SD alpha t and the variation of imaging variables eccentricity, width, and light blobs. Significant correlations (P < 0.05) were seen between % COMP alpha t and the variation of imaging variables area, perimeter, p2a, bending energy, nmac, sphericity, eccentricity, length, and width. A regression model for fertility rankings incorporating the standard deviation of the imaging variables area, bending energy, nmac, eccentricity, condensity, light blobs, and dark blobs was highly significant (r2 = 0.999, P < 0.05). These results indicate that variation of morphometry measurements is likely a sensitive biomarker related to fertility potential and abnormal chromatin structure.

Animals↗

Postponed aging and desiccation resistance in Drosophila melanogaster.

Studies with the fruit fly, Drosophila melanogaster, have repeatedly shown that selection for postponed reproduction leads to increases in mean life span and increased stress resistance; including increased resistance to desiccation, starvation and ethanol vapors. We show that desiccation resistance declines with age in both short- and long-lived flies suggesting that desiccation resistance may serve as a useful biomarker for aging-related declines in physiological performance. We examined the physical basis of desiccation resistance in five replicate populations selected for postponed reproduction and five replicate control populations. The variables examined were water content, rates of water loss during desiccation, and water content at time of death due to desiccation. In the absence of desiccation stress, both the flies exhibiting postponed senescence and their controls maintained constant water content throughout their lifetimes. In the presence of desiccation stress, the short-lived flies showed significantly higher rates of water loss at all ages than did the long-lived flies. Flies from the two treatments did not differ in water content at death. Our results indicate that water loss rates are the major determinant of desiccation resistance. Water loss rates are under genetic control and covary with age in populations with genetically-determined postponed senescence.

Aging↗

Improved in-hospital outcomes in acute coronary syndromes (unstable angina/non-ST segment elevation myocardial infarction) despite similar TIMI risk scores.

BACKGROUND: The Thrombolysis In Myocardial Infarction (TIMI) Risk Score has been shown to predict prognosis in acute coronary syndromes (ACS) comprised of unstable angina (UA) and non-ST segment elevation myocardial infarction (STEMI). We sought to evaluate the impact of newer antiplatelet and antithrombotic therapies for ACS, such as glycoprotein IIb/IIIa inhibitors (GPI) and low molecular weight heparin (LMWH), on in-hospital outcomes over time in patients (pts) with similar TIMI risk scores. METHODS: The baseline demographics and clinical outcomes of pts with ACS (UA and non-STEMI) in 1998 (Group 1998) and 2000 (Group 2000) at a single large university medical center were compared using a prospectively collected database. In-hospital major adverse cardiac events (MACE) included death, MI, or recurrent angina that resulted in urgent revascularization. Risk was estimated by utilizing the TIMI Risk Score, which uses 7 predictor variables: age > 65 years, at least 3 risk factors for coronary artery disease, prior coronary stenosis of 50%, ST segment deviation on EKG, severe angina, prior aspirin use, and elevated cardiac biomarkers. RESULTS: Comparing Group 1998 (n = 563) and Group 2000 (n = 604), there was no difference between the mean TIMI Risk Score (2.90 1.52 vs. 2.91 1.52; p = 0.97), demonstrating a similar risk profile. Nevertheless, significant improvement in in-hospital MACE (9.1% vs. 2.8%; p < 0.001) was noted. The improvement in MACE was due to differences in rates of recurrent angina, without significant differences in death and myocardial infarction. This occurred temporally in association with a significant increase in GPI (1.0% vs. 8.3%; p < 0.01) and LMWH (0.0% vs. 15.6%; p < 0.001) use within 24 hours of presentation, and the increased utilization of intracoronary stenting (46.6% vs. 64.6%; p = 0.005), findings which were confirmed with multivariate analysis. CONCLUSION: Despite similar TIMI Risk Scores, the in-hospital outcomes of pts with ACS have improved over time. This temporal change is associated with the greater use of newer antiplatelet and antithrombotic therapies and increased utilization of intracoronary stenting.

Aged↗

Quantitative nuclear morphometry, Markovian texture descriptors, and DNA content captured on a CAS-200 Image analysis system, combined with PCNA and HER-2/neu immunohistochemistry for prediction of prostate cancer progression.

One hundred and twenty-four localized prostate cancer patients operated on at Johns Hopkins Hospital (JHH) since 1975 were identified. The sample was optimized for evaluation of prostate cancer progression. Based upon accurate clinical histories, these radical prostatectomy patients included 50 progressors and 74 non-progressors using appearance of serum PSA as an indication of recurrence (mean follow-up = 8.6 +/- 1.8 years, range 7-15 years). All patients included in the study had no involvement of their seminal vesicles or lymph nodes at the time of prostatectomy. Average time to progression was 3.6 +/- 2 years, range of 1-8 years. Using paraffin-embedded specimens, several five micron sections were cut and placed on Probe-On slides; one slide was H&E-stained and the other was Feulgen-stained. The H&E and Feulgen-stained slides were screened and "dotted" by pathologists at JHH and CytoDynostics, Inc. A CAS-200 Image analysis system (Cell Image Systems, Elmhurst, IL) equipped with a Cell Measurement Program version 1.2 beta, was used to capture the Feulgen-stained images and to perform the calculations. From the "dotted" areas, 150 cancer cells were selected for measurement of DNA content and 27 nuclear morphometric shape and size factors, including 21 Markovian chromatin texture variables. Additional sections were used for immunochemistry staining with an alkaline phosphatase streptavidin-biotin complex stain to detect and quantitate cancer cells binding monoclonal antibodies directed against proliferating cell nuclear antigen (PCNA) and HER-2/neu antigen. All data were entered into a statistical program (STATA) for further analysis and univariate and multivariate statistical analysis was performed using logistic regression and its stepwise variant. The biomarkers of greatest utility to detect progressors when analyzed univariately included post-operative Gleason score (p = < 0.0001), HER-2/neu antigenicity (p = 0.0147), CAS-200 DNA ploidy (p = 0.008), and twelve Markovian nuclear texture and shape features (p = < 0.0001), whereas PCNA (p = 0.160) failed. The optimal set of nuclear morphometry progression tumor features were selected using backward stepwise logistic regression estimate analysis which drops variables due to collinearity. Although post-operative Gleason score is a strong univariate predictor of progression, DNA ploidy and HER-2/neu contributed significantly to further stratification of higher risk groups within the low Gleason score subpopulation. The best Markovian features combined with post-operative Gleason score generated sensitivity = 90%, specificity = 96%, positive predictive value = 94%, negative predictive value = 93% and the area under the receiver operator curve was 0.975.

Biomarkers, Tumor↗

Assessment of environmental and occupational exposures to butadiene as a model for risk estimation of petrochemical emissions.

1,3-Butadiene (BD) is an important industrial chemical and environmental contaminant, e.g. in urban air, traffic exhausts and tobacco smoke. It has been shown to be genotoxic in vitro and in vivo and carcinogenic in rodents, mice being more sensitive than rats. The present study confirmed this species difference. Using micronuclei in erythrocytes or bone marrow as a marker, mice responded at an effective level of 50 p.p.m., while the highest ineffective level in rats was 500 p.p.m. (inhalation of BD for 5 days). A dose-dependent increase in N-terminal valine haemoglobin adducts was seen in both rats and mice, but the adduct levels in the latter species were on average five times higher. For the first time, specific N6-alkyldeoxyadenosine adducts were identified in lung and liver DNA of rats exposed to BD by inhalation. No significant difference in DNA adduct level was seen in lung tissue of rats and mice at similar exposure levels. Occupational exposure levels to BD in the European Process industry are variable, but generally < 1 p.p.m. Haemoglobin adduct levels were seen to be increased among the worker groups with higher potential exposure to BD (process work, bomb voiding and repair duties) as compared with adduct levels in less exposed workers in maintenance and the laboratory or control personnel. However, the N-terminal valine haemoglobin adducts measured in the workers were one to two orders of magnitude lower than extrapolated for the same exposure dose in mice. In the same workers no exposure-related effects were seen in the cytogenetic parametres studied, i.e. chromosomal aberrations, sister chromatid exchanges or micronuclei in peripheral blood lymphocytes, or in the Ras oncoprotein levels of plasma samples. The studies so far conducted suggest that human exposure at the levels seen in the present day process industry can be documented at the biological dose level using haemoglobin adduct measurement, but not at the biological effect level using cytogenetic biomarkers. In order to quantitate the human genotoxic risk of BD exposure more work needs to be done on the role of other active BD metabolites than 1,2-epoxy-3-butene and on the genetic polymorphisms controlling the variability of individual responses.

Air Pollutants↗

Cytometric DNA analysis and prognostic biomarkers in breast carcinoma. Expression of P53 product in the different ploidy classes.

The aim of the study was to correlate the DNA Index (DI) and S-phase fraction (SPF) values determined by multiparametric flow cytometry in breast cancer (mainly T1 and T2 stages) with several clinico-pathologic variables and other biological parameters. For this purpose, a total of 136 breast cancers were submitted to flow cytometry and to several types of immunohistochemical analyses. Among clinico-pathologic data we considered pT, pN and grade and among immunohistochemical markers, hormonal receptors, P53, c-erbB-2 and MIB-1. We found that DNA aneuploidy was strongly correlated with high tumoral grade, absence of hormonal receptors, high proliferation, as shown by high MIB-1 (> or = 36%) and SPF values (> or = 13.3%), and P53 positivity. Grouping the tumours according to their DI values, we observed a relative significantly higher correlation of the near-triploid range carcinomas (DI 1.40-1.60) with immunohistochemical expression of P53 (p = 0.0001). Near-triploid DI was also associated with a high proliferative activity, expressed both by SPF (p = 0.0001) and MIB-1 reactivity (p = 0.0001), high tumoral grade (p = 0.0001) and presence of axillary metastases (p = 0.03). These data suggest that DNA near-triploid tumours in breast cancer may have a more aggressive behaviour in comparison with other DI classes.

Antigens, Nuclear↗

An Exosomal Signature for Preoperative Detection of Occult Liver Metastasis in Pancreatic Cancer.

IMPORTANCE: Early liver metastasis (early-LiM) after pancreatectomy represents an aggressive biological phenotype of pancreatic ductal adenocarcinoma (PDAC) and is associated with markedly poor survival. Reliable preoperative biomarkers to identify occult hepatic micrometastasis remain lacking. OBJECTIVE: To develop and externally validate a circulating exosomal microRNA (exo-miRNA)-based machine learning model for preoperative detection of occult early-LiM in PDAC. DESIGN, SETTING, AND PARTICIPANTS: This multicenter retrospective case-control study included 3 phases: genome-wide discovery using exo-miRNA sequencing (discovery cohort), model development (training cohort), and independent external validation (2 validation cohorts). The study took place at 4 medical centers in China, Japan, and South Korea. A total of 372 patients were enrolled between 2011 and 2024. Data were analyzed from July 2024 to November 2025. EXPOSURES: Circulating plasma-derived exosomal miRNA expression profiles. MAIN OUTCOMES AND MEASURES: The primary outcome was early-LiM, defined as liver recurrence within 6 months after curative-intent resection. Model performance was evaluated using the area under the receiver operating characteristic curve (AUC) and survival outcomes were assessed using Kaplan-Meier analysis. RESULTS: Among 372 patients with PDAC (median [IQR] age, 67 [59-73] years; 229 [61.6%] male and 143 [38.4%] female; median follow-up among survivors, 969 days),early-LiM was associated with significantly worse overall survival compared with other recurrence patterns (median OS, 9.1 months vs 26.6-31.8 months; log-rank P&#x2009;<&#x2009;.001). A 7-exo-miRNA extreme gradient boosting model demonstrated discrimination in the training cohort (AUC, 0.899; 95% CI, 0.822-0.976) and maintained performance in external testing cohorts (AUC, 0.876; 95% CI, 0.846-0.951 and AUC, 0.862; 95% CI, 0.744-0.981). The exo-miRNA panel score remained an independent identifier of early-LiM in multivariable analysis (odds ratio, 26.49; 95% CI, 18.45-55.28; P&#x2009;<&#x2009;.001) and stratified overall survival (log-rank P&#x2009;<&#x2009;.001). Decision curve analysis suggested improved net clinical benefit compared with conventional clinicopathologic variables. CONCLUSION AND RELEVANCE: In this multicenter study, a circulating exo-miRNA-based machine learning model enabled preoperative detection of occult early liver metastasis risk in PDAC. These findings support the potential of exosomal biomarkers to inform biology-guided treatment sequencing and warrant prospective validation.

Journal Article↗

Normal human IgD+IgM- germinal center B cells can express up to 80 mutations in the variable region of their IgD transcripts.

Somatic hypermutation in immunoglobulin variable region genes occurs within germinal centers. Here, we describe a subset of germinal center dark zone centroblasts that express only sIgD and have accumulated up to 80 mutations per heavy chain variable region (IgVH delta gene). Over half of the hypermutated IgVH delta sequences were found to be clonally related. This level of mutation is not observed in either IgVH gamma transcripts from the same sample or IgVH delta transcripts from peripheral blood, suggesting that these cells neither undergo isotype switch nor mature into circulating memory B cells. Optimal growth of these cells in vitro depends on CD40 ligand, T cell cytokines, and a fibroblast stroma, a combination possibly mimicking the dark zone microenvironment. Our hypothesis is that these cells may be sequestered within germinal centers, where their somatic mutation machinery is triggered. The isolation of these hypermutated B cells may represent a critical step for studying both the biology and biochemistry of somatic hypermutation.

ADP-ribosyl Cyclase↗

Reference data for bone mass, calciotropic hormones, and biochemical markers of bone remodeling in older (55-75) postmenopausal white and black women.

From a random sample of our institution's health maintenance organization (HMO), we recruited 250 white women and 112 black women, aged 55-75, all of whom were 10 or more years postmenospause with minimal estrogen exposure and free of osteoporosis, other metabolic bone disease, and medical, surgical, or therapeutic situations that may influence bone loss. Bone mass was measured in the radius, spine, and femur by DXA and in L1 by QCT. Serum samples were analyzed for parathyroid hormone, calcidiol, calcitriol, osteocalcin, and bone alkaline phosphatase and urine samples analyzed for creatinine, calcium, and hydroxyproline. Mean Z score, based on published reference data for forearm and femoral neck BMD in the white women, was not significantly different from zero, but mean Z score at the lumbar spine was 0.6 (p < 0.001), 17.2% of the individual values being > 2.0. In normal white women (BMI < 27.3, n = 143), Z score was still > 2.0 in 10.3%, suggesting that the upper bound of the published reference interval may be too low. After adjustment for body mass index, BMD was greater in the forearm (9.8%), spine (8.7%), and femoral neck (14.7%) in black women (p < 0.001 at all sites). At L1, adjusted BMC in the black women was 37.4% greater than in the white women (p < 0.001). Serum calcidiol was significantly lower and serum PTH and calcitriol significantly higher in the black women. Despite this, biochemical markers of bone resorption and formation were significantly lower in the black women. We conclude that skeletally healthy older black women have a greater bone mass and lower rates of bone remodeling than a comparable group of white women. These data can serve as reference intervals for the variables measured.

Aged↗

Pathologic prognostic factors for gastrointestinal cancer.

Numerous clinicopathologic factors have been reported to have prognostic significance for gastrointestinal cancer. Many problems, however, confront the surgeon assessing the extent of disease and the clinical and molecular pathologist distinguishing differences in tumor differentiation, behavior, and defining important prognostic markers of cancer. This review assesses current pathologic prognostic variables of gastric and colorectal cancer that have been reported to influence survival.

Biomarkers, Tumor↗

Peritoneal lavage with aprotinin in patients with severe acute pancreatitis. Effects on plasma and peritoneal levels of trypsin and leukocyte proteases and their major inhibitors.

CONCLUSION: Although high-dose aprotinin given intraperitoneally to patients with severe acute pancreatitis seems to inhibit activated trypsin in the peritoneal cavity, the treatment has little effect on the balance between proteases and antiproteases. Plasma levels of leukocyte proteases were high in all the patients, indicating leukocyte activation to be an important feature of the pathophysiology of severe acute pancreatitis. A surprise finding was that the patients had higher peritoneal levels of pancreatic secretory trypsin inhibitor (PSTI) after the lavage procedure. BACKGROUND: Although most studies have shown protease inhibitor therapy to have little or no effect on acute pancreatitis, in an earlier study we found that very high doses of the protease inhibitor aprotinin given intraperitoneally to patients with severe acute pancreatitis seemed to reduce the need of surgical treatment for pancreatic necrosis. In the present study we have further analyzed plasma and peritoneal samples from the same patients to ascertain whether the aprotinin treatment affects the balance between proteases and endogenous antiproteases. METHODS: In a prospective double-blind randomized multicenter trial, 48 patients with severe acute pancreatitis were treated with intraperitoneal lavage. One group (aprotinin group, n = 22) was also treated with high doses (20 million KIU given over 30 h) of aprotinin intraperitoneally. The remaining 26 patients made up the control group. The protease-antiprotease balance was studied by measuring immunoreactive anionic trypsin (irAT), cationic trypsin (irCT), complexes between cationic trypsin and alpha 1-protease inhibitor (irCT-alpha 1 PI), leukocyte elastase and neutrophil proteinase 4 (NP4), as well as the endogenous protease inhibitors, pancreatic secretory trypsin inhibitor (PSTI), alpha 2-macroglobulin (alpha 2M), alpha 1-protease inhibitor (alpha 1 PI), antichymotrypsin (ACHY), and secretory leukocyte protease inhibitor (SLPI). Intraperitoneal levels were studied before and after the lavage procedure, and plasma levels were followed for 21 d. RESULTS: The control group had lower plasma levels of SLPI and analysis of peritoneal fluid showed the reduction of irCT-alpha 1 PI to be more pronounced in the aprotinin group. None of the other variables measured differed significantly between the two groups. All patients had very high levels of leukocyte elastase and NP4 both in peritoneal exudate and in plasma. Peritoneal levels of PSTI were higher after the lavage procedure in contrast to the other measured variables that all showed lower peritoneal levels after the lavage.

Acute Disease↗

Absence of retinoblastoma gene product in human primary oral cavity carcinomas.

Oral cavity cancer is a major health concern worldwide. Despite advances in surgery, radiotherapy and chemotherapy over the past 35 years, there has been no significant enhancement in the survival of oral cavity cancer patients. Improved survival will require identification of reliable prognostic markers that provide a rational basis for assessment of risk for progression. The altered retinoblastoma (RB) gene has been linked to the hereditary retinoblastoma. This gene is defective in several types of human malignancies. The intent of this study was to evaluate the role of the RB gene in oral cavity tumorigenesis and to explore whether or not there is a relationship between the loss of RB protein and each of several clinicopathological parameters in oral cavity carcinomas. We have analysed the expression of the RB gene in four cell lines (J82, ML1, SaOS2 and WERI-RB-1), 182 oral cavity carcinomas (75 T1 and 107 T3 and T4 lesions) and 55 normal tissues adjacent to cancer by means of an immunohistochemical method and Western immunoblotting. The expression of RB protein was then correlated with clinical outcome in the patients with primary tumours. The significantly higher rate of altered RB expression was found in advanced oral cavity tumours (40 of 107; 37%) in comparison with low grade tumours (9 of 75; 7%). In T3 and T4 tumours, RB gene expression did not correlate with presence or absence of lymph node metastasis, degree of differentiation and patient survival. However, in the T1 cohort, poorer survival rate was seen for those patients who had a tumour with loss of RB protein. This study suggests that tumours in which the RB protein was altered were more aggressive than tumours in which the RB protein was present and that loss of RB protein in oral cavity cancer may be a prognostic variable of tumour progression.

Biomarkers, Tumor↗