Trace element and isotope deposition across the air-sea interface: progress and research needs.

The importance of the atmospheric deposition of biologically essential trace elements, especially iron, is widely recognized, as are the difficulties of accurately quantifying the rates of trace element wet and dry deposition and their fractional solubility. This paper summarizes some of the recent progress in this field, particularly that driven by the GEOTRACES, and other, international research programmes. The utility and limitations of models used to estimate atmospheric deposition flux, for example, from the surface ocean distribution of tracers such as dissolved aluminium, are discussed and a relatively new technique for quantifying atmospheric deposition using the short-lived radionuclide beryllium-7 is highlighted. It is proposed that this field will advance more rapidly by using a multi-tracer approach, and that aerosol deposition models should be ground-truthed against observed aerosol concentration data. It is also important to improve our understanding of the mechanisms and rates that control the fractional solubility of these tracers. Aerosol provenance and chemistry (humidity, acidity and organic ligand characteristics) play important roles in governing tracer solubility. Many of these factors are likely to be influenced by changes in atmospheric composition in the future. Intercalibration exercises for aerosol chemistry and fractional solubility are an essential component of the GEOTRACES programme.This article is part of the themed issue 'Biological and climatic impacts of ocean trace element chemistry'.

Viral degradation of marine bacterial exopolysaccharides.

The identification of the mechanisms by which marine dissolved organic matter (DOM) is produced and regenerated is critical to develop robust prediction of ocean carbon cycling. Polysaccharides represent one of the main constituents of marine DOM and their degradation is mainly attributed to polysaccharidases derived from bacteria. Here, we report that marine viruses can depolymerize the exopolysaccharides (EPS) excreted by their hosts using five bacteriophages that infect the notable EPS producer, Cobetia marina DSMZ 4741. Degradation monitorings as assessed by gel electrophoresis and size exclusion chromatography showed that four out of five phages carry structural enzymes that depolymerize purified solution of Cobetia marina EPS. The depolymerization patterns suggest that these putative polysaccharidases are constitutive, endo-acting and functionally diverse. Viral adsorption kinetics indicate that the presence of these enzymes provides a significant advantage for phages to adsorb onto their hosts upon intense EPS production conditions. The experimental demonstration that marine phages can display polysaccharidases active on bacterial EPS lead us to question whether viruses could also contribute to the degradation of marine DOM and modify its bioavailability. Considering the prominence of phages in the ocean, such studies may unveil an important microbial process that affects the marine carbon cycle.

Intralobular growth of myoepithelial cell carcinoma of the breast.

Two cases of intralobular carcinoma of the breast showing myoepithelial cell differentiation are reported. One was an in situ lesion localized within a fibroadenoma; the second was predominantly in situ, but areas of invasion were present. The neoplastic cells had round to ovoid nuclei and were polygonal to spindle in shape displaying glycogen rich clear cytoplasm. Alpha-smooth muscle actin was present in the cytoplasm of the neoplastic cells in both cases. In one case the same cells displayed cytoplasmic microfilaments at electron microscopic level. Intralobular growth of neoplastic myoepithelial cells has never been described in the literature, and this line of differentiation has to be added to the endocrine and apocrine features occasionally observed in in situ lobular carcinomas of the breast.

Amyloid tumours in the soft tissues of the legs. Case report and review of the literature.

We present a case of multiple amyloidomas occurring in the calves of a 61-year-old woman, without systemic amyloidosis or plasma cell dyscrasia. The disappearance of Congo red positivity after potassium permanganate treatment and immunohistochemical results showed that this was a case of reactive AA amyloidosis. True soft tissue amyloidomas are extremely rare, and this is the first case of AA amyloidoma in the soft tissues of the legs.

Breast cancer in young women: clinicopathological features and biological specificity.

Literature data suggest that breast cancers occurring in young patients may be different from those arising in older women. In this study the clinicopathologic characteristics of 50 patients under 40 years of age were compared with those of patients aged over 60. Patients under 40 years old more frequently had a family history of breast cancer than did older patients (24% vs 17%) and had more often used oral contraceptives (29% vs 13%); on average they had experienced menarche 1 year earlier. For early onset breast carcinomas there was a higher frequency of grade 3 tumours (38% vs 17%) and oestrogen receptor negativity (46% vs 20%). In addition, in younger patients the carcinomas were mostly DNA aneuploid (78% vs 58%), with a higher proliferation rate (48% vs 26%) and more frequent c-erbB-2 overexpression (48% vs 26%) and p53 alteration (30% vs 8%). Our data demonstrate that breast cancers arising in young women have a significantly different biopathological profile from those in older patients, with a predominance of unfavourable prognostic parameters.

Leiomyoma of the breast: case report and review of the literature.

We describe a case of leiomyoma in the breast in a 48-year-old woman. The main clinical-pathologic features together with the differential diagnosis, and the pertinent literature reviewed.

Biopathological significance of single cell DNA aneuploidy measured by static cytometry in breast cancer.

DNA ploidy image analysis in breast carcinomas has occasionally revealed cases with a diploid DNA content but with a single hypertetraploid element, the so-called single cell aneuploidy (SCA). To identify the biologic significance of this little known phenomenon, we selected 40 cases with SCA from a series of 599 consecutive operable breast carcinomas. The clinical, pathological and biological characteristics of SCA cases were compared with those of a control group of 40 pure diploid breast carcinomas. Hormonal receptor status, proliferative indexes (Ki-67) and p53 overexpression were determined immunohistochemically and quantitatively evaluated by image analysis. The overexpression of c-erbB-2 was determined semiquantitatively. SCA was observed in 6.6% of cases (40 of 599) and in 17% of otherwise diploid cases (40 of 236). Breast cancers with SCA occur in younger women (mean age 54.75 y vs 61.12 y, P<0.05), are smaller (mean diameter 20.00 vs 21.62 mm), less differentiated (percentage of G3 cases 13.2 vs 2.9), more frequently hormone independent (ER positivity 70.0 vs 77.5%; PgR positivity 57.5 vs 77.5%) and have a greater cell proliferative activity (mean S-phase: 4.6 vs 2.8, P<0.05), (percentage of Ki-67 immunostaining: 24.1 vs 19.7%). There is also more overexpression of c-erbB-2 and P53, particularly in pT1 cases in which the percentage of c-erbB-2 positive cells is 54 vs 32 (P value is not significant) and the percentage of p53 is 29 vs 4 (P<0.05). According to these results SCA may be a reliable marker of genetic instability and of greater biologic aggressiveness. Image cytometry of DNA content may be a cost effective means of identifying breast cancer patients with an increased risk of tumour recurrences despite otherwise favourable prognostic parameters.

Prognostic indexes in breast cancer: comparison of the Nottingham and Adelaide indexes.

The search for single independent prognostic factors in breast cancer has often produced conflicting results. Therefore, prognostic indexes have been compiled by combining several parameters. In this study we compare the Nottingham Prognostic Index (NPI), which is based on traditional prognostic factors (diameter of the neoplasm, lymph node status and histological grade) with the Adelaide Prognostic Index (API), which is based on the tumour diameter and two biological parameters: oestrogen receptors and cell kinetics. We considered 82 cases of breast cancer observed over the period 1987-1990 with a minimum follow-up of 60 months. The NPI gives a better definition of the prognostic profile for each patient. Our results indicate three prognostic groups (good, moderate, unfavourable), which differ with respect to disease-free survival (DFS; P=0.0024) and overall survival (OS; P=0.0033). In contrast, the API scores showed no significant correlation with OS or DFS. The use of prognostic indexes, especially when compiled using traditional parameters, is a useful aid to the clinician, since they can provide a reliable indication of how individual tumours will evolve.

Value of c-erbB-2 and p53 oncoprotein co-overexpression in human breast cancer.

p53 and c-erbB-2 protein expression was immunohistochemically examined in a consecutive series of 49 primary breast cancer patients with a 10-year follow-up. The study was performed on paraffin sections using the monoclonal antibodies DO7 and CBE1; the former recognizes both the wild-type and the mutant p53 forms, the latter recognizes the external domain of the transmembrane c-erbB-2 protein. Positive staining was expressed in 12.2% and 16.3% of cases for p53 and c-erbB-2 proteins, respectively. The results were related to clinicopathological parameters by the chi 2 test. A significant correlation was found between positive c-erbB-2 immunostaining and poor survival (P = 0.04) and between p53 and c-erbB-2 overexpression (P = 0.003); this co-overexpression correlated well with a poor clinical outcome (P = 0.040). From our results, we may speculate that simultaneous expression of p53 and c-erbB-2 oncoproteins could be a critical event in breast tumor progression, and therefore, of prognostic value to identify patients at high risk.

Membranous glomerulonephritis in congenital syphilis.

The glomerulonephritis of congenital syphilis is thought to be immune-complex mediated. We describe a case of C. S. in whom the only manifestation was a glomerulonephritis. Immunopathogenic studies allowed the identification of treponemal antigen in glomeruli. The elution of immunoglobulins from renal tissue showed that glomerular deposits contained antitreponemal antibodies. Cryoglobulins with antitreponemal activity were also isolated from the patient's serum.

Spontaneous dissecting aneurysm of coronary artery in a pregnant woman at term.

We describe a case of spontaneous dissecting aneurysm of the circumflex coronary artery in a 44-year-old primigravida at term with no vascular risk factors. Spontaneous coronary artery dissection is a very rare condition with a greater prevalence in women, postpartum in particular. The left anterior descending artery is the most frequently affected. Histologically, the most common finding is a hematoma occupying the outer third of the media, resulting in complete compression of the true lumen. Arterial wall changes during pregnancy together with hemodynamic factors, a lytic action of protease released from eosinophils, and intimal tears are the main hypotheses considered to explain the etiology of spontaneous coronary artery dissection.

Giant cell tumor of tendon sheath: immunohistochemical study of 20 cases.

AIMS AND BACKGROUND: Giant cell tumor of tendon sheath (GCTTS) is a common tumor occurring on the tendon sheaths of the fingers. The nature of this lesion is still controversial: some researchers consider it a reactive process arising from chronic inflammation while others regard it as a tumor of presumed synovial cell or monocytic macrophage system origin. In an effort to clarify the histogenesis we decided to further investigate the immunophenotypic profile of this tumor. STUDY DESIGN: We studied 20 GCTTS of the fingers using a panel of 18 antibodies, 13 monoclonal and 5 polyclonal. RESULTS: The immunohistochemical investigation revealed that the mononuclear cells of this lesion can be divided into two groups. The cells of the first and more numerous group were positive for vimentin, PG-M1 and KP1 but also for muscle actin (HHF35 monoclonal antibody) and neuron-specific enolase. A second population of mononuclear cells, usually arranged around the giant cells, were positive for PG-M1, KP1, LCA and occasionally for alpha-1-antitrypsin and alpha-1-antichymotrypsin. Multinucleated giant cells were also positive for KP1, PG-M1 and LCA monoclonal antibodies. A variable but usually weak positivity for alpha-1-antitrypsin, alpha-1-antichymotrypsin and lysozyme was also observed. CONCLUSIONS: Our results suggest a synovial cell origin for GCTTS and do not support the hypothesis that it could be a neoplasm with a true histiocytic origin. The positivity of some cells for the HHF35 antibody, together with electron microscopic evidence of filament bundles with focal dense bodies, suggests that at least part of the mononuclear cells may have a myofibroblastic differentiation.

Bilateral primary malignant lymphoma of the breast. A case report.

A case of bilateral primary malignant lymphoma of the breast in a 30 year old woman is described. The tumors were first discovered during a self-examination of the breast at the 7th month of pregnancy. Thereafter they rapidly increased in size. The patient underwent simple bilateral mastectomy, and histological examination revealed a centroblastic/centrocytic lymphoma. The patient is alive and well 9 months after mastectomy.