Frequency and distribution of occult micrometastases in lymph nodes of patients with non-small-cell lung carcinoma

BACKGROUND

Accurate assessment of the presence and absence of tumor in the regional lymph nodes is critical in assessment of prognosis for patients with lung cancer. Development of sensitive immunohistochemical techniques and specific monoclonal antibodies has increased our capacity, in melanoma and breast cancer, to detect small groups of tumor cells or even single tumor cells in lymph nodes that appear to be tumor free in conventionally stained sections.

PURPOSE

This retrospective study was designed to assess whether use of a polyclonal antikeratin reagent in immunohistochemical analysis offers any advantage over conventional histopathology in detection of regional lymph node metastases in non-small-cell lung cancer.

METHODS

Paraffin-embedded tissue sections from regional lymph nodes of 65 patients with non-small-cell lung cancer were studied. We examined tissue from 588 nodes of 60 patients with a diagnosis of disease confined to the lung and from 72 nodes of five patients with a diagnosis of metastasis to some nodes. A polyclonal antikeratin antibody was applied to the lymph node tissue sections, using the avidin-biotin complex immunoperoxidase technique.

RESULTS

Single tumor cells and small clusters of tumor cells (occult micrometastases) not visible on routine evaluation were readily detected in 38 (63%) of the 60 patients whose nodes appeared to be negative on examination of hematoxylin-eosin-stained slides. In the five patients with a diagnosis of node-positive non-small-cell lung cancer, five (10%) of 51 nodes that were tumor free on conventional examination contained metastases. Metastatic tumor cells were most often located in the subcapsular or medullary sinuses. The lymph nodes that contained occult tumor cells were those located nearest to the tumor, mainly in peribronchial and hilar locations. The median survival of patients with occult metastases (1977 days) was shorter than that of patients whose nodes contained no tumor (2456 days) but was longer than that of patients whose nodes contained metastases detectable on hematoxylin-eosin-stained slides (927 days).

CONCLUSIONS

Our results suggest that, in patients with non-small-cell lung cancer, metastatic involvement of regional lymph nodes is more frequent than was previously determined by the conventional histologic method and substantially more frequent than in other tumor types, such as melanoma and breast cancer.

IMPLICATIONS

The high frequency of occult nodal metastases in non-small-cell lung cancer makes it clear that, without immunohistochemistry, disease is understaged in many patients. Therefore, it seems essential that immunohistochemical evaluation of the lymph nodes be undertaken in clinical trials.

Ecotoxicological evaluation of four UV filters using marine organisms from different trophic levels Isochrysis galbana, Mytilus galloprovincialis, Paracentrotus lividus, and Siriella armata

Due to the concern about the negative effects of exposure to sunlight, combinations of UV filters like 4-Methylbenzylidene-camphor (4-MBC), Benzophenone-3 (BP-3), Benzophenone-4 (BP-4) and 2-Ethylhexyl-4-methoxycinnamate (EHMC) are being introduced in all kind of cosmetic formulas. These chemicals are acquiring a concerning status due to their increasingly common use and the potential risk for the environment. The aim of this study is to assess the behaviour of these compounds in seawater, the toxicity to marine organisms from three trophic levels including autotrophs (Isochrysis galbana), herbivores (Mytilus galloprovincialis and Paracentrotus lividus) and carnivores (Siriella armata), and set a preliminary assessment of potential ecological risk of UV filters in coastal ecosystems. In general, EC50 results show that both EHMC and 4-MBC are the most toxic for our test species, followed by BP-3 and finally BP-4. The most affected species by the presence of these UV filters are the microalgae I. galbana, which showed toxicity thresholds in the range of μg L(-1) units, followed by S. armata>P. Lividus>M. galloprovincialis. The UV filter concentrations measured in the sampled beach water were in the range of tens or even hundreds of ng L(-1). The resulting risk quotients showed appreciable environmental risk in coastal environments for BP-3 and 4-MBC.

The relationship between internal chain length of amylopectin and crystallinity in starch

Molecular models of amylopectin were created and investigated by computer simulation. First, single and double helices of various lengths were constructed. The 1 --> 6 branching in double and single helices of amylopectin was studied. Subunits of single helices, double helices, and branch points were used as building blocks of larger systems. The possible makeup of amylopectin unit clusters was investigated via a series of models, including single-single, double-single, and double-double helix systems. The lengths of the single helix section that linked two branch points (internal chains) was systematically varied between values of 0-10 glucose residues. It was found that certain internal chain lengths lead to parallel double helices. Thus, it was postulated that the length of internal chains may determine the degree of local crystallinity. Furthermore, it was noted that some of the low-energy arrangement of double helices could be superimposed on either the two adjacent and nonadjacent double helices of crystalline A and B starch polymorphs. In other cases, the distance between the double helices is so large that it may in fact be a model for branching between two amylopectin crystals or unit clusters. Results obtained through this work were corroborated, where possible, with information available from crystallographic, branching, and enzymatic studies.

The significance of Acinetobacter baumannii bacteraemia compared with Klebsiella pneumoniae bacteraemia: risk factors and outcomes

Risk factors and outcomes for patients with nosocomial Acinetobacter baumannii bacteraemia were compared with those for patients with nosocomial Klebsiella pneumoniae bacteraemia in a single centre in Israel between 2000 and 2003. Data were collected retrospectively through patient chart review. In total, 112 patients with A. baumannii bacteraemia and 90 patients with K. pneumoniae bacteraemia were identified. A. baumannii was significantly associated with poorer performance status, mechanical ventilation, presence of devices, prior treatment with carbapenems, pneumonia as the source of infection and inappropriate empirical antibiotic treatment. All-cause 30-day mortality was higher for A. baumannii bacteraemia compared with K. pneumoniae bacteraemia (61.6% vs 38.9%, P=0.001). Variables significantly associated with mortality at the univariate level (P<0.1) were entered into a multi-variable logistic regression model for mortality. A. baumannii remained significantly associated with mortality when adjusted for all other risk factors (odds ratio 3.61, 95% confidence interval 1.55-8.39). This result did not change when the analysis was repeated for subgroups of less severely ill patients, i.e. those who were not ventilated and those who did not present with septic shock. These results support the view that nosocomial bacteraemia due to A. baumannii is associated with increased mortality.

Characteristics of candidaemia with Candida-albicans compared with non-albicans Candida species and predictors of mortality

Candidaemia due to non-albicans Candida species is increasing in frequency. We describe 272 episodes of candidaemia, define parameters associated with Candida albicans and other Candida species, and analyse predictors associated with mortality. Patients with C. albicans (55%) had the highest fatality rate and frequently received immunosuppressive therapy, while patients with Candida parapsilosis (16%) had the lowest fatality and complication rates. Candida tropicalis (16%) was associated with youth, severe neutropenia, acute leukaemia or bone marrow transplantation, Candida glabrata (10%) was associated with old age and chronic disease, and Candida krusei (2%) was associated with prior fluconazole therapy. The overall fatality rate was 36%, and predictors of death by multi-variate analysis were shock, impaired performance status, low serum albumin and congestive heart failure. Isolation of non-albicans Candida species, prior surgery and catheter removal were protective factors. When shock was excluded from analysis, antifungal therapy was shown to be protective. Unlike previous concerns, infection with Candida species other than C. albicans has not been shown to result in an increased fatality rate.

Functional analysis of bovine herpesvirus 1 (BHV-1) genes expressed during latency

Bovine herpes virus 1 (BHV-1) establishes latency in sensory neurons of trigeminal ganglia (TG), and germinal centers of pharyngeal tonsil. Periodically BHV-1 reactivates from latency, virus is shed, and consequently virus transmission occurs. Two transcripts, the latency related (LR) RNA and ORF-E, are abundantly expressed in TG of latently infected cattle. A LR mutant strain of BHV-1 was constructed that contains stop codons near the beginning of the LR-RNA. The LR mutant virus does not express two proteins encoded by the LR gene, or reactivate from latency suggesting that LR protein expression regulates the latency-reactivation cycle. Higher levels of apoptosis occur in TG of calves infected with the LR mutant versus wild type BHV-1 indicating that the anti-apoptotic properties of the LR gene regulate the latency-reactivation cycle. The LR gene also inhibits bICP0 expression and mammalian cell growth, but these functions do not require LR protein expression. In contrast, the ability of the LR gene to inhibit apoptosis appears to require LR protein expression. A small open reading frame (ORF-E) that is located within the LR promoter is expressed in the nucleus of neuroblastoma cells. We predict that the LR gene and ORF-E regulate the BHV-1 latency-reactivation cycle.

Bracing for loss

People find unexpected bad news aversive and often brace themselves by predicting the worst. Three experiments examined whether the pessimism is influenced by personal need. Students who differed in financial need learned that a billing error meant that some students would receive an additional bill from their university. Financially needy students were consistently pessimistic in predicting their likelihood of receiving a bill, whereas non-needy students were not. In addition, the experiments reveal that (a) the pessimism occurred for potential losses but not potential gains, (b) needy students were pessimistic about their own chances but not the chances of a friend, (c) the pessimism was not attributable to needy students' being more readily primed by the news of a possible bill or to needy students' having more experience with billing errors, and (d) the pessimism was specific to monetary losses and did not generalize to other events.

Multicenter evaluation of a new screening test that detects Clostridium difficile in fecal specimens

Clostridium difficile causes approximately 25% of nosocomial antibiotic-associated diarrheas and most cases of pseudomembranous colitis. We evaluated C. DIFF CHEK, a new screening test that detects glutamate dehydrogenase of C. difficile. Our results showed that this test was comparable to PCR in sensitivity and specificity and outperformed bacterial culture.

Transcription factor ATF3 partially transforms chick embryo fibroblasts by promoting growth factor-independent proliferation

Activating Transcription Factor 3 (ATF3) is a member of the bZip family of transcription factors. Previous studies in mammalian cells suggested that like other bZip family members e.g. Jun and Fos, ATF3 might play a role in the control of cell proliferation and participate in oncogenic transformation. To investigate this putative ATF3 function directly, the rat ATF3 protein was compared with v-Jun for its ability to transform primary cultures of chick embryo fibroblasts (CEFs). Like CEFs accumulating v-Jun, CEFs accumulating the ATF3 protein displayed a typical, fusiform morphology, associated with an enhanced capacity to grow in medium with reduced amount of serum. However, in contrast to v-Jun-transformed CEFs, the ATF3 overexpressing cells could not promote colony formation from single cells in agar. Partial transformation induced by ATF3 was found to be associated with repression of multiple cellular genes that are also down-regulated by v-Jun, including those coding for the extracellular components fibronectin, decorin, thrombospondin 2, and the pro-apoptotic protein Par-4. These data demonstrate that, at least in primary avian cells, rat ATF3 possesses an intrinsic oncogenic potential. Moreover, the results suggest that ATF3 might induce growth factor independence by down-regulating a subset of the genes repressed by v-Jun.

Light-induced catalytic transformation of ofloxacin by solar Fenton in various water matrices at a pilot plant: mineralization and characterization of major intermediate products

This work investigated the application of a solar driven advanced oxidation process (solar Fenton), for the degradation of the antibiotic ofloxacin (OFX) in various environmental matrices at a pilot-scale. All experiments were carried out in a compound parabolic collector pilot plant in the presence of doses of H2O2 (2.5 mg L(-1)) and at an initial Fe(2+) concentration of 2 mg L(-1). The water matrices used for the solar Fenton experiments were: demineralized water (DW), simulated natural freshwater (SW), simulated effluent from municipal wastewater treatment plant (SWW) and pre-treated real effluent from municipal wastewater treatment plant (RE) to which OFX had been spiked at 10 mg L(-1). Dissolved organic carbon removal was found to be dependent on the chemical composition of the water matrix. OFX mineralization was higher in DW (78.1%) than in SW (58.3%) at 12 mg L(-1) of H2O2 consumption, implying the complexation of iron or the scavenging of hydroxyl radicals by the inorganic ions present in SW. On the other hand, the presence of dissolved organic matter (DOM) in SWW and RE, led to lower mineralization per dose of H2O2 compared to DW and SW. The major transformation products (TPs) formed during the solar Fenton treatment of OFX, were elucidated using liquid chromatography-time of flight-mass spectrometry (LC-ToF-MS). The transformation of OFX proceeded through a defluorination reaction, accompanied by some degree of piperazine and quinolone substituent transformation while a hydroxylation mechanism occurred by attack of the hydroxyl radicals generated during the process leading to the formation of TPs in all the water matrices, seven of which were tentatively identified. The results obtained from the toxicity bioassays indicated that the toxicity originates from the DOM present in RE and its oxidation products formed during the photocatalytic treatment and not from the TPs resulted from the oxidation of OFX.

Transformation products and reaction pathways of carbamazepine during photocatalytic and sonophotocatalytic treatment

This study examines the degradation of the antiepileptic carbamazepine (CBZ) by sonolysis, TiO2-based heterogeneous photocatalysis under UV-A and simulated solar irradiation, and by the combined use of UV-A and ultrasound irradiation (i.e. sonophotocatalysis) in demineralized water, ground water and effluent wastewater. The processes were compared with respect to substrate conversion rate and the extent of DOC reduction as a measure of mineralization. CBZ was degraded following a pseudo-first order kinetics. Sonophotocatalysis provided the highest rate of CBZ transformation over the time-course of the experiment while the degree of DOC removal in pure water was similar for all the studied treatments (around 40%), and always lower than CBZ conversion. This indicated that a considerable organic load remained in the treated solutions that could also be attributed to the presence of persistent oxidation products. UPLC-(+ESI)-QToF-MS was employed to determine major CBZ-related transformation products. Several recalcitrant hydroxy- and keto-derivatives of CBZ were tentatively identified. A Daphnia magna bioassay was used to evaluate the potential toxicity of the samples collected at different time points showing that the mixtures were highly toxic to D. magna.

Solar photocatalytic treatment of trimethoprim in four environmental matrices at a pilot scale: transformation products and ecotoxicity evaluation

The pilot-scale solar degradation of trimethoprim (TMP) in different water matrices (demineralized water: DW, simulated natural freshwater: SW; simulated wastewater: SWW; and real effluent: RE) was investigated in this study. DOC removal was lower in the case of SW compared to DW, which can be attributed to the presence of inorganic anions which may act as scavengers of the HO·. Furthermore, the presence of organic carbon and higher salt content in SWW and RE led to lower mineralization per dose of hydrogen peroxide compared to DW and SW. Toxicity assays in SWW and RE were also performed indicating that toxicity is attributed to the compounds present in RE and their by-products formed during solar Fenton treatment and not to the intermediates formed by the oxidation of TMP. A large number of compounds generated by the photocatalytic transformation of TMP were identified by UPLC-QToF/MS. The degradation pathway revealed differences among the four matrices; however hydroxylation, demethylation and cleavage reactions were observed in all matrices. To the best of our knowledge this is the first time that TMP degradation products have been identified by adopting a solar Fenton process at a pilot-scale set-up, using four different aqueous matrices.

Two-step (culture and PCR) diagnostic approach for differentiation of non-T. foetus trichomonads from genitalia of virgin beef bulls in Argentina

Preputial fluids from 567 virgin Angus and Hereford bulls, 1-2 years old, were inoculated into Sutherland medium, and approximately 8.4% produced cultures with a protozoan suggestive of Tritrichomonas foetus. Under brightfield microscopy, large numbers of single-celled motile organisms with multiple anterior flagellae, a posterior flagellum, axostyle, and a visible undulating membrane were detectable. Motility was jerky and rolling, as described for T. foetus. Air-dried smears of cultures stained with Giemsa or Diff-Quick + iodine revealed an organism similar to T. foetus, although somewhat more rounded. Several organisms appeared to have four anterior flagellae. Scanning electron microscopy (5000x) of representative samples revealed four anterior flagellae on most organisms, and an axostyle that was consistently longer than that seen in T. foetus. Using pan-trichomonal primers and T. foetus-specific primers in a polymerase chain reaction (PCR) assay, amplification products of 372bp were detected in all virgin bull isolates, but only with the pan-trichomonal primers. Positive control isolates of T. foetus yielded amplification products of the expected size (372 and 347bp) with the two sets of primers, respectively. We conclude that these protozoa are not T. foetus, and note the similarity of these findings with those reported earlier in North American beef cattle. Because in several countries there is no legal treatment for bovine trichomonosis, veterinarians recommend slaughter of bulls with positive preputial cultures. The existence of easily mis-identified non-T. foetus trichomonads in the bovine prepuce suggests that the current "gold standard" diagnostic test (culture of preputial scrapings or washings) should be augmented with a more specific confirming test, such as the PCR employed in this study.

Transcription factor ATF2 cooperates with v-Jun to promote growth factor-independent proliferation in vitro and tumor formation in vivo

ATF2 belongs to the bZIP family of transcription factors and controls gene expression via 8-bp ATF/CREB motifs either as a homodimer or as a heterodimer-for instance, with Jun-but has never been shown to be directly involved in oncogenesis. Experiments were designed to evaluate a possible role of ATF2 in oncogenesis in chick embryo fibroblasts (CEFs) in the presence or absence of v-Jun. We found that (i) forced expression of ATF2 cannot alone cause transformation, (ii) overexpression of ATF2 plus v-Jun specifically stimulates v-Jun-induced growth in medium with a reduced amount of serum, and (iii) the efficiency of low-serum growth correlates with the activity of a Jun-ATF2-dependent model promoter in stably transformed CEFs. Analysis of ATF2 and Jun dimerization mutants showed that the growth-stimulatory effect of ATF2 is likely to be mediated by v-Jun-ATF2 heterodimers since (i) v-Jun-m1, a mutant with enhanced affinity for ATF2, induces growth in low-serum medium much more efficiently than v-Jun, when expressed alone or in combination with ATF2; and (ii) ATF2/fos, a mutant that efficiently binds to v-Jun but is unable to form stable homodimers, shows enhanced oncogenic cooperation with v-Jun. In addition, we examined the role of ATF2 in tumor formation by subcutaneous injection of CEFs into chickens. In contrast to v-Jun, v-Jun-m1 gave rise to numerous fibrosarcomas while coexpression of ATF2 and v-Jun-m1 led to a dramatic development of fibrosarcomas visible within 1 week. Together these data demonstrate that overexpressed ATF2 potentiates the ability of v-Jun-transformed CEFs to grow in low-serum medium in vitro and contributes to the formation of tumors in vivo.

Intrapleural chemotherapy for patients with incompletely resected malignant mesothelioma: the UCLA experience

From 1986 to 1993, 15 patients with malignant pleural mesothelioma were treated by pleurectomy/decortication and intrapleural cisplatin (100 mg/m2) and cytosine arabinoside (1,200 mg). All patients were without known extrathoracic disease and had a mean age of 63 +/- 7.9 years (range 51-78); 13 were male. Histologic subtype of disease were epithelial (47%), sarcomatoid (27%), and mixed-biphasic (27%). The major morbidity and mortality rates were 13% and 0%, respectively. The mean length of hospital stay was 6.5 +/- 2.1 days. Postoperatively, adjuvant chemotherapy and radiation therapy were given to 46% and 73% of the patients respectively. Median survival from date of treatment was 11.5 months. Those patients with an epithelial histologic subtype experienced significantly improved survival compared to those of sarcomatoid subtype (P = 0.024). Whether adjuvant chemotherapy or radiation therapy were given had no significant effect on survival. These data suggest that although this treatment regimen can be administered with very limited morbidity and no mortality, the role of this approach in the treatment of malignant pleural mesothelioma appears limited and cannot currently be recommended.

Antiurolithiatic activity of Raphanus sativus aqueous extract on rats

The aqueous extract of the bark of Raphanus sativus was tested for its antiurolithiatic and diuretic activity. The urolithiasis was experimentally induced by implantation of zinc disc in the urinary bladder of rats. Significant decrease in the weight of stones was observed after treatment in animals which received aqueous extract in comparison with control groups. This extract showed an increase in the 24 h urine volume as compared to the control.

Crystal structure of β-D-acetyl cellobiose, C28H38O19

The crystal structure of β-D-acetyl cellobiose was studied by X-ray crystallography. The crystal data are a = 31.814(4), b = 19.414(5), c = 5.614(1) Å, space group P212121, Z = 4. The structure, solved by direct method, was refined by block-diagonal least-squares to a final R value of 0.075 for 2605 observed reflections. The molecular conformation involves 4C1 pyranose rings with glycosidic torsion angles corresponding to near maximum extension of the molecule. Substantial differences in conformational angles were observed between this molecule and the unacetylated counterpart. The molecules lie along the a-axis of the unit cell.

Immunoregulatory effects of fraction 5 thymus peptides. I. Thymosin alpha 1 enhances while thymosin beta 4 suppresses the human autologous and allogeneic mixed lymphocyte reaction

Thymosin alpha 1 and thymosin beta 4, two peptides isolated from preparations of calf thymus fraction 5, were tested in the human mixed lymphocyte reaction (MLR). Thymosin alpha 1 was found capable of enhancing both the allogeneic and autologous MLR. On the contrary, thymosin beta 4 suppressed MLR proliferative responses. Study of the responses of the T cell subpopulations revealed that T4+ (helper/inducer) cells but not T8+ (suppressor/cytotoxic) are responsible for the enhanced, proliferative response to allo- and autoantigens in the presence of thymosin alpha 1. Both the autologous and the allogeneic proliferative responses of either T4+ cells or T8+ cells were not influenced by the addition of thymosin beta 4 in the cultures. However, when T4+ and T8+ subsets were cocultured, thymosin beta 4 was capable of activating T8+ cells to suppress the allogeneic and the autologous proliferative response of T4+ cells. These studies show that thymosin fraction 5 peptides exert immunoregulatory effects on the human MLR proliferative responses in vitro.

The monosaccharide binding site of lentil lectin: an X-ray and molecular modelling study

The X-ray crystal structure of lentil lectin in complex with alpha-D-glucopyranose has been determined by molecular replacement and refined to an R-value of 0.20 at 3.0 A resolution. The glucose interacts with the protein in a manner similar to that found in the mannose complexes of concanavalin A, pea lectin and isolectin I from Lathyrus ochrus. The complex is stabilized by a network of hydrogen bonds involving the carbohydrate oxygens O6, O4, O3 and O5. In addition, the alpha-D-glucopyranose residue makes van der Waals contacts with the protein, involving the phenyl ring of Phe123 beta. The overall structure of lentil lectin, at this resolution, does not differ significantly from the highly refined structures of the uncomplexed lectin. Molecular docking studies were performed with mannose and its 2-O and 3-O-m-nitro-benzyl derivatives to explain their high affinity binding. The interactions of the modelled mannose with lentil lectin agree well with those observed experimentally for the protein-carbohydrate complex. The highly flexible Me-2-O-(m-nitro-benzyl)-alpha-D-mannopyranoside and Me-3-O-(m-nitro-benzyl)-alpha-D-mannopyranoside become conformationally restricted upon binding to lentil lectin. For best orientations of the two substrates in the combining site, the loss of entropy is accompanied by the formation of a strong hydrogen bond between the nitro group and one amino acid, Gly97 beta and Asn125 beta, respectively, along with the establishment of van der Waals interactions between the benzyl group and the aromatic amino acids Tyr100 beta and Trp128 beta.