Depth of the vadose zone controls aquifer biogeochemical conditions and extent of anthropogenic nitrogen removal.

We investigated biogeochemical conditions and watershed features controlling the extent of nitrate removal through microbial dinitrogen (N2) production within the surficial glacial aquifer located on the north and south shores of Long Island, NY, USA. The extent of N2 production differs within portions of the aquifer, with greatest N2 production observed at the south shore of Long Island where the vadose zone is thinnest, while limited N2 production occurred under the thick vadose zones on the north shore. In areas with a shallow water table and thin vadose zone, low oxygen concentrations and sufficient DOC concentrations are conducive to N2 production. Results support the hypothesis that in aquifers without a significant supply of sediment-bound reducing potential, vadose zone thickness exerts an important control of the extent of N2 production. Since quantification of excess N2 relies on knowledge of equilibrium N2 concentration at recharge, calculated based on temperature at recharge, we further identify several features, such as land use and cover, seasonality of recharge, and climate change that should be considered to refine estimation of recharge temperature, its deviation from mean annual air temperature, and resulting deviation from expected equilibrium gas concentrations.

The efficacy of neoadjuvant chemotherapy compared to postoperative therapy in the treatment of locally advanced breast cancer.

The current approach to the treatment of locally advanced breast cancer is sequential chemotherapy, surgery and/or radiation, and consolidation chemotherapy. Although significant tumor response is seen with this regimen, there are few studies that compare this approach to postoperative chemotherapy. The purpose of this study was to compare the disease-free and overall survival of patients with locally advanced breast cancer treated with neoadjuvant chemotherapy and surgery to patients treated with surgery followed by adjuvant chemotherapy. Ninety-four patients with stage IIB, IIIA, and IIIB breast cancer were treated with a standardized chemotherapy regimen. The first group, 60 patients who were followed prospectively, was treated with neoadjuvant chemotherapy (NCT) consisting of vincristine, prednisone, cytoxan, methotrexate, and 5-FU (CVFMP) followed by surgery and consolidation chemotherapy with adriamycin. The second group, 34 patients evaluated retrospectively, had surgery followed by postoperative chemotherapy (PCT) with CVFMP followed by adriamycin. Overall median follow-up was 38 months. In the NCT group, 45/60 (75%) patients had a clinical response to induction therapy and the median reduction in tumor size was 50%. The rates of local recurrence, distant recurrence, and death from disease were similar in the two groups. The time to local recurrence was similar for the two groups. However, the median time to distant recurrence was shorter in the NCT group (19 month vs. 31 months, p = NS). Overall median survival among the NCT patients was shorter than for the PCT group (30 vs. 47 months, p = NS). The current study suggests that postoperative therapy is comparable to a neoadjuvant regimen in patients with locally advanced breast cancer with regard to local recurrence, distant recurrence, and overall survival.

The NS2 polypeptide of parvovirus MVM is required for capsid assembly in murine cells.

Mutants of minute virus of mice (MVM) which express truncated forms of the NS2 polypeptide are known to exhibit a host range defect, replicating productively in transformed human cells but not in cells from their normal murine host. To explore this deficiency we generated viruses with translation termination codons at various positions in the second exon of NS2. In human cells these mutants were viable, but showed a late defect in progeny virion release which put them at a selective disadvantage compared to the wildtype. In murine cells, however, duplex viral DNA amplification was reduced to 5% of wildtype levels and single-strand DNA synthesis was undetectable. These deficiencies could not be attributed to a failure to initiate infection or to a generalized defect in viral gene expression, since the viral replicator protein NS1 was expressed to normal or elevated levels early in infection. In contrast, truncated NS2 gene products failed to accumulate, so that each mutant exhibited a similar NS2-null phenotype. Expression of the capsid polypeptides VP1 and VP2 and their subsequent assembly into intact particles were examined in detail. Synchronized infected cell populations labeled under pulse-chase conditions were analyzed by differential immunoprecipitation of native or denatured extracts using antibodies which discriminated between intact particles and isolated polypeptide chains. These analyses showed that at early times in infection, capsid protein synthesis and stability were normal, but particle assembly was impaired. Unassembled VP proteins were retained in the cell for several hours, but as the unprocessed material accumulated, capsid protein synthesis progressively diminished, so that at later times relatively few VP molecules were synthesized. Thus in NS2-null infections of mouse cells there is a major primary defect in the folding or assembly processes required for effective capsid production.

Structure of music may influence cognition.

Classical music has been said to enhance cognition, which effect may be related to musical structure. 19 subjects who listened to highly structured music scored somewhat higher afterwards on cognitive performance than the 15 who listened to less structured music. Since this did not reach statistical significance, other as yet unidentified factors may also be involved.

Structure determination of minute virus of mice.

The three-dimensional crystal structure of the single-stranded DNA-containing ('full') parvovirus, minute virus of mice (MVM), has been determined to 3.5 A resolution. Both full and empty particles of MVM were crystallized in the monoclinic space group C2 with cell dimensions of a = 448.7, b = 416.7, c = 305.3 A and beta = 95.8 degrees. Diffraction data were collected at the Cornell High Energy Synchrotron Source using an oscillation camera. The crystals have a pseudo higher R32 space group in which the particles are situated at two special positions with 32 point symmetry, separated by (1/2)c in the hexagonal setting. The self-rotation function showed that the particles are rotated with respect to each other by 60 degrees around the pseudo threefold axis. Subsequently, a more detailed analysis of the structure amplitudes demonstrated that the correct space-group symmetry is C2 as given above. Only one of the three twofold axes perpendicular to the threefold axis in the pseudo R32 space group is a 'true' crystallographic twofold axis; the other two are only 'local' non-crystallographic symmetry axes. The known canine parvovirus (CPV) structure was used as a phasing model to initiate real-space electron-density averaging phase improvement. The electron density was easily interpretable and clearly showed the amino-acid differences between MVM and CPV, although the final overall correlation coefficient was only 0.63. The structure of MVM has a large amount of icosahedrally ordered DNA, amounting to 22% of the viral genome, which is significantly more than that found in CPV.

The prognostic significance of previous benign breast disease for women with carcinoma of the breast.

BACKGROUND: Risk factors for carcinoma of the breast may also have prognostic influence. Because benign breast disease is a risk factor for carcinoma of the breast, we compared the outcomes of patients with carcinoma of the breast with a history of benign breast disease to patients with carcinoma of the breast without a history of benign breast disease. STUDY DESIGN: Patients with benign breast disease and subsequent carcinoma of the breast were matched by age and ethnicity to patients with carcinoma of the breast with no prior history of benign breast disease. Risk factors, pathologic findings, and disease-free survival rates were compared. RESULTS: Patients with previous benign breast disease had a significantly greater family history of carcinoma of the breast (35 percent compared with 22 percent, p = 0.015) and used postmenopausal hormones significantly more frequently (16 percent compared with 5 percent; p < 0.001) than women without benign breast disease. In patients with benign breast disease, their subsequent carcinomas were smaller (T1, 53 percent compared with 43 percent), with significantly fewer nodes involved (1.8 compared with 2.7, p = 0.031), and were significantly more likely to contain an infiltrating lobular component (9 percent compared with 3 percent, p = 0.023). Significantly fewer patients with previous benign breast disease had metastatic disease (18 percent compared with 31 percent; p = 0.001). The ten-year cumulative disease-free survival rate for patients with benign breast disease was 68 percent compared with 59 percent for women without a history of benign breast disease. CONCLUSIONS: This study indicates that women with benign breast disease who have carcinoma of the breast develop may have a better outcome than women without a history of benign breast disease.

Ethnic differences in risk and prognostic factors for breast cancer.

BACKGROUND: Poor survival among African American patients with breast cancer has been attributed to low socioeconomic status and lack of access to health care. However, Hispanics of equivalent socioeconomic status and health care access exhibit much higher survival rates, almost comparable to whites. This suggests that biologic differences play a role in differences in breast cancer survival in addition to socioeconomic and health care access factors. METHODS: The authors studied clinical and molecular differences between patients with breast cancer of different ethnicity to determine biologic explanations for the observed differences in survival. Consecutive patients scheduled for breast biopsies were identified preoperatively and were interviewed. Blood was withdrawn for serum marker measurements, and tumor specimens collected at frozen section diagnosis were analyzed by flow cytometry, hormone receptor concentration, tumor grade, and Ki-67 nuclear antigen, HER-2/neu, and epidermal growth factor oncoprotein expression. RESULTS: Age, age at menarche, number of lymph nodes with metastasis, estrogen and progesterone receptor levels, ploidy status, S-phase, Ki-67, HER-2/neu expression, tumor grade, epidermal growth factor receptor expression, lipid-associated sialic acid (LASA), and carcinoembryonic antigen level were not significantly related to ethnicity. African Americans presented at a significantly more advanced stage and with significantly larger tumors. They were significantly heavier and had a significantly higher mean Quetelet's index and a significantly higher number of pregnancies and number of live births. Whites and Hispanics were significantly older at menopause. CONCLUSIONS: The molecular indices associated with breast cancer prognosis do not differ significantly among whites, African Americans, and Hispanics, suggesting that the reported differences in survival among these groups are not due to biologic differences in breast cancer among ethnic groups.

The significance of family history for patients with carcinoma of the breast.

BACKGROUND: Since the risk of carcinoma of the breast is increased in women with a family history of the disease, new primary carcinomas of the breast may be increased after treatment. Women with several relatives with carcinoma of the breast are thought to be at higher risk of having a second primary carcinoma of the breast develop and mastectomy is more frequently recommended. STUDY DESIGN: The computerized registry of the Mount Sinai Medical Center Breast Service was used to identify 1,337 patients with complete information concerning family history. Three hundred fifty-nine patients with a family history of carcinoma of the breast were compared with women with no family history. RESULTS: Compared with patients with no family history of carcinoma of the breast, patients with a family history of carcinoma of the breast were significantly younger (54.0 versus 55.8 years of age, p < 0.01), were significantly more likely to have used oral contraceptives (26 versus 13 percent, p < 0.001), had significantly more ductal carcinoma in situ (10 versus 4 percent, p < 0.01), and were significantly more often treated with breast conservation (42 versus 31 percent, p < 0.001). Simultaneous contralateral carcinoma of the breast was diagnosed more frequently in patients with a family history (3 versus 1 percent, p < 0.025), but metachronous contralateral carcinomas were not increased. In comparing the two groups, there were no significant differences in proportion premenopausal, parity, use of postmenopausal hormones, tumor size, tumor differentiation, nodal involvement, TNM stage, estrogen receptor status, or use of adjuvant radiation, chemotherapy, or tamoxifen. Complete five-year follow-up evaluation for 748 patients, 179 with a family history, found no differences in local, distant, or disease-free survival rates for mastectomy or breast conservation in relation to family history. Outcome for patients with first-degree affected relatives and those with more than one affected relative was the same as those with no family history. CONCLUSIONS: These results indicate that women with a family history of carcinoma of the breast should be treated no differently than women with no family history.

Replication of herpes simplex virus type 1 on hydroxyurea-resistant baby hamster kidney cells.

Hydroxyurea-resistant (HUr) baby hamster kidney cells were isolated, subcloned, and characterized. One clonal line, which contained elevated levels of ribonucleotide reductase, lost its HU resistance during passage in the absence of the inhibitor, whereas another clonal line was stably resistant. The replication of herpes simplex virus type 1 on these cells was compared with that of the parvovirus minute virus of mice. Herpes simplex virus type 1 was found to be as sensitive to HU on both lines of HUr baby hamster kidney cells as it was on parental (HU-sensitive) cells, whereas parvovirus replication was about eight times more resistant on HUr baby hamster kidney cells compared with the parental cells. The results suggest that herpes simplex virus type 1 cannot use the cellular reductase and may code for its own.

Reciprocal productive and restrictive virus-cell interactions of immunosuppressive and prototype strains of minute virus of mice.

Viral and cellular factors responsible for parvovirus target cell specificity have been examined for two serologically indistinguishable strains of the minute virus of mice which infect mouse cells of dissimilar differentiated phenotype. Both the prototype strain and the immunosuppressive strain grow in and form plaques on monolayers of simian virus 40-transformed human fibroblasts, a finding that has allowed the comparison of several aspects of their virus-host cell interactions. Although closely related by antigenic and genomic criteria, both the prototype strain and the immunosuppressive strain are restricted for lytic growth in each other's murine host cell, that is, in T cells and fibroblasts, respectively. The host range of each virus variant appears to be specified by a genetic determinant that is stably inherited in the absence of selection. In the restrictive virus-host interaction lytic growth is limited to a small or, in some cases, undetectable subset of the host cell population, and the majority of the infected cells remain viable, continuing to grow at the normal rate without expressing viral antigens. The susceptible host cell phenotype is dominant in T lymphocyte x fibroblast fusion hybrids, implying that different cell types express different developmentally regulated virus helper functions that can only be exploited by the virus variant that carries the appropriate strain-specific determinant.

Occult thyroid carcinoma appearing as a single mandibular metastasis.

Extraglandular well-differentiated follicular thyroid tissue in the head and neck can originate from aberrant embryologic rests, by separation from the main gland through strap muscle action, by 'benign metastatic" seeding of the cervical lymphatics, and from mixed papillary-follicular or pure follicular carcinoma. The management of this ectopic tissue is controversial. A case of occult follicular carcinoma with a sole metastasis to the mandible is presented.