Residual metastatic axillary lymph nodes following neoadjuvant chemotherapy predict disease-free survival in patients with locally advanced breast cancer

BACKGROUND: This study was performed to validate the prognostic significance of residual axillary lymph node metastases in patients with locally advanced breast cancer (LABC) treated with neoadjuvant chemotherapy and to analyze other clinicopathologic factors that might be independent predictors of disease-free survival (DFS) in an attempt to identify patients in whom axillary dissection might be omitted. METHODS: One hundred sixty-five assessable patients with LABC were treated in a prospective trial of neoadjuvant chemotherapy utilizing four cycles of 5-fluorouracil, doxorubicin, and cyclophosphamide. Responding patients were treated with segmental mastectomy and axillary dissection or modified radical mastectomy. Patients subsequently received additional chemotherapy followed by irradiation of the breast or chest wall and draining lymphatics. The median follow-up was 35 months. RESULTS: Clinical tumor response to neoadjuvant chemotherapy (P = 0.046) and the number of residual metastatic axillary lymph nodes found at axillary dissection (P = 0.05) were the only independent predictors of DFS. Patients with a complete clinical response had a predictably excellent DFS and those with no change or progressive disease had a poor DFS. In patients with a partial response, the number of residual metastatic lymph nodes further stratified patients with respect to DFS (P = 0.006). CONCLUSIONS: Clinical response and residual metastatic axillary lymph nodes following neoadjuvant chemotherapy are important predictors of DFS. Patients with a clinically positive axilla following neoadjuvant chemotherapy should undergo axillary dissection to ensure local control. However, the benefit of axillary dissection in patients with a clinically negative axilla may be minimal if the axilla will be irradiated, and histologic staging does not affect subsequent systemic treatment. A prospective randomized trial of axillary dissection versus axillary radiotherapy in patients with a clinically negative axilla following neoadjuvant chemotherapy is presently under way to evaluate this hypothesis.     

The response of asthmatic subjects to isoproterenol inhaled at differing lung volumes

Asthmatics are usually instructed to use pressurized bronchodilator aerosols by delivering a bolus of drug at the beginning of a full inspiration. Because airways are better dilated near total lung capacity, the delivery of the drug near the end of a full breath might allow better penetration of particles into the lung and greater bronchodilatation. To test this hypothesis, 13 asthmatic subjects inhaled 400 mug of isoproterenol at 20 per cent (low) and at 80 per cent (high) vital capacity. The studies were done on 2 separate days when the severity of asthma was the same. Forced vital capacity, 1-sec forced expiratory volume, specific airway conductance and maximal flow at 50 per cent of viral capacity were measured at frequent intervals after drug administration. Ten min after drug delivery, there was a significantly greater (P less than 0.05) improvement in 1-sec forced expiratory volume after the drug was inhaled at the high lung volume compared to the response after delivery at the low lung volume. The differences in forced vital capacity, specific conductance, and maximal flow at 50 per cent of vital capacity were not significant. We concluded that inhaling a bronchodilator drug at the end of a full inspiration causes relatively greater bronchodilatation than inhaling the same dose at the beginning of inspiration.     

Nodular intercapillary glomeruloscerosis in diabetes secondary to chronic calcific pancreatitis

Nodular (specific) intercapillary glomerulosclerosis (Kimmelstiel-Wilson) was found at autopsy in a 47-year-old man who had been diabetic for 20 years. The family history for this disease had been negative. Both the clinical course and the autopsy findings strongly suggest that this patient's diabetes was secondary to chronic fibrocalcific pancreatitis. This is only the fourth recorded case of histologically documented nodular glomerulosclerosis occurring in a patient with pancreatogenic diabetes.     

Determination of total dietary fiber in foods and food products by using a single-enzyme, enzymatic-gravimetric method: interlaboratory study

A simplified enzymatic-gravimetric method for total dietary fiber (TDF) determination has been published and used in the Food Composition Laboratory of the U.S. Department of Agriculture since 1988. THis method gives comparable results to AOAC Official Methods 985.29 and 991.43 but the AOAC methods use 100 degrees C (water bath) to gelatinize the sample and a combination of alpha-amylase and an amyloglucosidase to hydrolyze starches, whereas the simplified method incorporates an autoclaving step (121 degrees C) for gelatinization followed by incubation with only amyloglucosidase. The simplified method omits protease hydrolysis and does not require any pH adjustment. Overall, the simplified method cuts cost and is less labor intensive. An interlaboratory study was conducted to validate this method. Blind duplicates of six sample (baked beans, corn bran, roasted peanuts, cooked potatoes, white bread with reduced calories, and cooked white rice) were sent to 11 laboratories. The reproducibility relative standard deviations of the TDF values (without outliers) ranged from 3.46 to 27.6%. The repeatability standard deviations ranged from 0.91 to 14.6%.     

Influence of iron-limited continuous culture on physiology and virulence of Legionella pneumophila

A virulent strain of Legionella pneumophila serogroup 1, subgroup Pontiac, was grown in continuous culture at a constant growth rate under iron-replete and iron-limited conditions. Iron limitation was achieved by the removal of ferrous sulfate and hemin from the chemically defined medium. Residual contaminating iron, 0.45 microM, was sufficient to support iron-limited growth. Typical iron-replete cultures metabolized 3.3 microM iron. Serine provided the principal source of carbon and energy for both cultures, although iron-replete cultures also depleted a number of other amino acids. There was a 40% decrease in culture biomass under iron-restricted conditions. Iron limitation did not significantly affect carbohydrate metabolism, with the molar growth yield for carbon (Ycarbon) comparable for both cultures. However, under iron-limited conditions a sixfold increase in Yiron correlated with a significant decrease in the iron content of the biomass, as the culture utilized the available iron more efficiently. Highly pleomorphic iron-replete cultures became uniform cultures of short fine rods when adapted to iron-deficient conditions. In addition to the morphological and physiological changes, iron limitation had a critical effect on culture virulence. The virulence of this strain was significantly (P < 0.05) reduced when the culture was subjected to iron-limited conditions. This phenomenon was reversible, with a significant increase in culture virulence upon reversion to iron-replete conditions. When compared in an in vitro macrophage assay, the number of culturable avirulent iron-limited cells located intracellularly after infection was significantly lower than for the virulent replete and control cultures. These results further support the role of environmental parameters in regulating the virulence of L. pneumophila.     

Effects of estrogen on gene expression in the chick oviduct. Isolation and fractionation of chromatin non-histone proteins

Non-histones isolated from hen oviduct chromatin have been fractionated by a variety of methods. Chromatin was dissociated in 2 M NaC1, 5 M Urea, 0.1% beta-mercaptoethanol and 0.01 M Tris - HC1, pH 8.3, and the DNA removed by ultracentrifugation. After desalting by gel filtration the chromatin proteins were separated into three distinct fractions by stepwise elution with 0.10 M NaC1, 0.25 M Na C1 and 15% guanidine - HC1 from Bio-Rex 70 columns. Fractions I and II contain only non-histones and Fraction III contains histones plus a small amount of non-histones. Further fractionation of the non-histones was achieved by ammonium sulfate precipitation and DEAE-cellulose chromatography for Fraction I and phosphocellulose chromatography and gel filtration on Bio-Gel A-15 m for Fraction II. The histone and non-histones present in Fraction III were separated by gel filtration on Bio-Gel A-0.5 m. All fractionation methods have been used preparatively with reasonable recoveries of protein (greater than or equal to 60%). The fractions have been characterized by acrylamide gel electrophoresis. The integrity of the histones was maintained during the fractionation procedure indicating that proteolytic degradation was unlikely to have occurred. There was no selective loss of chromatin proteins during the ultracentrifugation and desalting steps and the non-histones were separated into distinct fractions with enrichment of some species not apparent prior to fractionation of the chromatin proteins.     

Effect of estrogen on gene expression in the chick oviduct. Effect of estrogen on the sequence and population complexity of chick oviduct poly(A)-containing RNA

Total cellular RNA preparations were isolated from chicken oviducts at three different development stages: (a) immature chicks which were chronically stimulated with estrogen; (b) estrogen-stimulated chicks which were then withdrawn from hormone for 12 days; and (c) laying hens. Total cellular RNA containing 3'-poly(A) sequences (poly(A)-RNA) were than isolated from these preparations using oligo(dT)-cellulose chromatography. The number average nucleotide length of the poly(A)-RNA preparations in each case was approximately 2000 nucleotides. The number average nucleotide length of the poly(A) residues at the 3'-terminal end of each RNA preparation was approximately 70 adenylate residues. Complementary DNA (cDNA) copies to each preparation of poly(A)-RNA were synthesized using avian myeloblastosis virus RNA-directed DNA polymerase. The cDNApoly(A) preparations were then utilized in DNA excess hybridization experiments to analyze the complexity of the DNA sequences from which these RNAs were transcribed. Approximately 22% of each of the total cellular poly(A)-RNAs were transcribed from repeated DNA sequences (average repeat frequency of 35 copies/genome) while the remaining majority were transcribed from single copy or unique sequence DNA. It was possible to estimate the number of different poly(A)-RNA sequences per cell by analyzing the kinetics of hybridization of these cDNApoly(A) preparations to total cellular poly(A)-RNA extracts under conditions of RNA excess. The results revealed that 41% of the poly(A)-RNA from laying hen oviduct consisted of, on the average, three different sequences/cell, each of which was present in approximately 25,000 copies/cell. The remainder of the poly(A)-RNA in this tissue consisted of approximately 25,000 different sequences/cell, which were present largely in only two or three copies/cell. A somewhat similar sequence complexity was found for oviduct cells prepared from estrogen-stimulated chicks. We estimated that there were approximately 20,000 different poly(A)-RNA sequences/cell, each represented in only one to two copies/cell. However, there were five sequences which were present, on the average, in a concentration of 5600 copies/cell. The poly(A)-RNAs from hormone-wtihdrawn tissue, on the other hand, had a lower sequence complexity. There were only approximately 10,000 different poly(A)-RNA sequences/cell, each present in about three copies/cell. Furthermore, the few sequences present in a great abundance in hen and hormone-stimulated tissues were apparently absent in oviduct tissue from hormone-wtihdrawn chicks, suggesting that the intracellular concentrations of these high frequency RNA sequences are dependent on estrogen.