Influence of Adjunct Use and Cheese Microenvironment on Nonstarter Bacteria in Reduced-Fat Cheddar-Type Cheese

This study investigated population dynamics of starter, adjunct, and nonstarter lactic acid bacteria (NSLAB) in reduced-fat Cheddar and Colby cheese made with or without a Lactobacillus casei adjunct. Duplicate vats of cheese were manufactured and ripened at 7 degrees C. Bacterial populations were monitored periodically by plate counts and by DNA fingerprinting of cheese isolates with the random amplified polymorphic DNA technique. Isolates that displayed a unique DNA fingerprint were identified to the species level by partial nucleotide sequence analysis of the 16S rRNA gene. Nonstarter biota in both cheese types changed over time, but populations in the Colby cheese showed a greater degree of species heterogeneity. The addition of the L. casei adjunct to cheese milk at 10(4) cfu/ml did not completely suppress "wild" NSLAB populations, but it did appear to reduce nonstarter species and strain diversity in Colby and young Cheddar cheese. Nonetheless, nonstarter populations in all 6-mo-old cheeses were dominated by wild L. casei. Interestingly, the dominant strains of L. casei in each 6-mo-old cheese appeared to be affected more by adjunct treatment and not cheese variety.

Increased AKT activity contributes to prostate cancer progression by dramatically accelerating prostate tumor growth and diminishing p27Kip1 expression

The PTEN tumor suppressor gene is frequently inactivated in human prostate cancers, particularly in more advanced cancers, suggesting that the AKT/protein kinase B (PKB) kinase, which is negatively regulated by PTEN, may be involved in human prostate cancer progression. We now show that AKT activation and activity are markedly increased in androgen-independent, prostate-specific antigen-positive prostate cancer cells (LNAI cells) established from xenograft tumors of the androgen-dependent LNCaP cell line. These LNAI cells show increased expression of integrin-linked kinase, which is putatively responsible for AKT activation/Ser-473 phosphorylation, as well as for increased phosphorylation of the AKT target protein, BAD. Furthermore, expression of the p27(Kip1) cell cycle regulator was diminished in LNAI cells, consistent with the notion that AKT directly inhibits AFX/Forkhead-mediated transcription of p27(Kip1). To assess directly the impact of increased AKT activity on prostate cancer progression, an activated hAKT1 mutant was overexpressed in LNCaP cells, resulting in a 6-fold increase in xenograft tumor growth. Like LNAI cells, these transfectants showed dramatically reduced p27(Kip1) expression. Together, these data implicate increased AKT activity in prostate tumor progression and androgen independence and suggest that diminished p27(Kip1) expression, which has been repeatedly associated with prostate cancer progression, may be a consequence of increased AKT activity.

Borderline tumors of the ovary: correlation of frozen and permanent histopathologic diagnosis

OBJECTIVE

To evaluate the correlation between the diagnosis of borderline tumor of the ovary by frozen and permanent pathology.

METHODS

All pathology reports with diagnoses of borderline tumor of the ovary between 1980 and 1998 at Massachusetts General Hospital were reviewed. Univariate and multivariable logistic regression models were constructed for patient age, tumor size, histology, presence of bilateral or extraovarian disease, and concurrent diagnosis of endometriosis or endosalpingiosis.

RESULTS

We reviewed 140 cases. The average age of patients was 52.3 years. Eighty tumors were serous, 47 mucinous, 11 mixed, and two endometrioid. The mean diameter overall was 13.7 cm (range 1-70 cm), 10.2 cm for serous, and 20.1 cm for mucinous. Diagnoses of borderline tumors by frozen and permanent pathology were consistent in 60% of cases. Frozen section interpreted a benign lesion as malignant (overdiagnosed) in 10.7% of cases, and interpreted a malignant lesion as benign (underdiagnosed) in 29.3%. No variable was a significant predicator of overdiagnosis. In univariate analysis, underdiagnosis was more likely for other types of tumors than serous (P <.001), tumors larger than 20 cm (P =.039), and tumors confined to the ovaries (P =. 009). When all variables were included in a multiple regression model, only histology was a significant predictor of underdiagnosis (P =.039).

CONCLUSION

Frozen or permanent pathology reports of diagnoses of borderline tumor were consistent 60% of the time, whereas the positive predictive value of borderline by frozen section was 89.3%. Tumors other than serous are more likely to be misinterpreted.

Quality of Life in Advanced Ovarian Cancer: Identifying Specific Concerns

PURPOSE

To identify issues affecting the quality of life (QoL) in women receiving palliative therapy for ovarian cancer.

METHODS

Twenty women with advanced recurrent ovarian cancer were interviewed to establish what issues affect QoL. All patients were receiving palliative chemotherapy or other palliative therapy in the department of Gynecologic Oncology at the Massachusetts General Hospital, and were felt to have a life expectancy of 1 year or less by best clinical estimate.

RESULTS

Twenty patients with an average age of 56.7 years participated. Psychosocial issues were more common than physical ones, and patients were more likely to mention issues that positively impact on QoL rather than those with a negative effect. Most patients noted that a sense of hope, enhanced appreciation for day to day life, and a strong support system had a significantly positive effect on QoL. Issues negatively impacting QoL included fear of their disease (90%) and concern for family and friends (100%), particularly children. Most common physical symptoms impacting QoL included fatigue (100%) and anorexia (55%).

CONCLUSIONS

Little research has been done into QoL issues for ovarian cancer patients receiving palliative care. Available QoL studies tend to focus on the physical aspects of a disease or its treatment. This pilot study suggests that women with advanced, recurrent ovarian cancer feel that psychosocial issues play a greater role in determining QoL than do physical issues. Further QoL studies for these patients should include assessment of psychosocial realms. This information can then be used to design interventions to improve QoL.

Conditional transformation of rat embryo fibroblast cells by a cyclin D1-cdk4 fusion gene

Cyclin D1 gene overexpression is a frequent event in a number of human cancers. These observations have led to the suggestion that cyclin D1 alterations might play a role in the etiology of cancer. This possibility is supported by the finding that transfection of mammalian cells with cyclin D1 can accelerate progression through the G1 phase of the cell cycle. Moreover, cyclin D1 can function as an oncogene by cooperating with activated Ha-ras to transform primary rat embryo fibroblasts (REFs). In addition, cyclin D1 transgenics develop hyperplasia and neoplasia of the thymus and mammary gland. We have constructed a novel fusion gene consisting of full-length human cyclin D1 and cdk4 genes. This fusion gene was expressed in insect cells and the fusion protein was shown to be enzymatically active. The fusion gene was expressed in mammalian cells under the control of tet-repressor. This fusion gene immortalized primary REFs, and cooperated with activated Ha-ras to transform primary REFs, in terms of anchorage-independent growth in vitro and formation of tumors in vivo. Utilizing a tet-regulated gene expression system, we have shown that proliferation of stably transfected primary REFs in vitro and in vivo is dependent on the continued expression of the cyclin D1-cdk4 fusion gene. These cell lines could be useful in the discovery of novel cancer therapeutics to modulate cyclin D1.cdk4 activity.

Fruit juice intake is not related to children's growth

BACKGROUND

Excessive fruit juice intake (>12 ounces/day) has been reported to be associated with short stature and obesity in preschool children.

OBJECTIVE

To confirm whether excess fruit juice intake was associated with short stature and obesity in preschool children, we assessed growth parameters and fruit juice intake in 105 white children, ages 24 to 36 months.

METHODOLOGY

Mothers were interviewed twice by a registered dietitian when children were age 24, 28, or 32 months (interview 1) and when children were age 28, 32, or 36 months (interview 2); interviews were assigned randomly. At each interview mothers provided 3 days of dietary data (one 24-hour recall and a 2-day food record) and the registered dietitian weighed the child and measured his/her height. Dietary data were analyzed using Nutritionist IV software. Each child's body mass index (wt/ht2) and ponderal index (wt/ht3) were calculated for each interview. Growth parameters of children consuming <12 ounces/day 100% fruit juice were compared with those consuming >/=12 ounces/day using the Student's t test, chi2, Fisher's exact test, and mixed model repeated measures analyses (PROC MIXED).

RESULTS

Results consistently indicated no statistically significant differences in children's height, body mass index, or ponderal index related to fruit juice intake. Intakes of soda pop were negatively related to intakes of milk and fruit juice although intakes of milk and fruit juice were not related.

CONCLUSIONS

The consistent lack of relationship between children's fruit juice intake and growth parameters in our study does not support previous recommendations to limit the intake of 100% fruit juice to <12 ounces/day.

The phenomenon of "picky eater": a behavioral marker in eating patterns of toddlers

OBJECTIVE

To determine if toddlers who were considered "picky eaters" had lower dietary scores than non-picky eaters, and if family environment and socioeconomic status were significantly related to picky eater status and dietary scores.

METHODS

An incomplete block design provided two interviews at randomly assigned times (24, 28, 32, or 36 months) of Caucasian mothers from upper socioeconomic (n=74) and lower socioeconomic status (n=44). Using trained interviewers, 6 days of food intake, two administrations of a questionnaire about toddler's eating behavior, and one administration of the Family Environment Scales were collected in the home. MANOVA, discriminant function analysis, and logistic regression procedures were used to determine significant differences between picky and non-picky eater groups.

RESULTS

Picky eaters had lower dietary variety (p=.03) and diversity scores (p=.009) than non-picky eaters. Mothers of picky eaters compared to those of non-picky eaters used persuasion (p=.0001) and ranked their child's eating behaviors as more problematic (p=.0001).

CONCLUSION

Toddlers perceived by their mothers as picky eaters had significantly lower dietary variety and diversity scores. Parents need information and strategies to increase the number of foods acceptable to their toddlers and to develop a sound feeding plan.

Transitions in infant feeding during the first year of life

OBJECTIVE

To document ages at which transitions in infant feeding occur, to compare these transitions to literature reports from the 1970s and 80s, and to identify maternal characteristics related to the age of the infant when solid food was first introduced.

METHODS

Ninety-eight mother/infant pairs (middle and upper socioeconomic status) participated in the longitudinal study. Using a randomized, incomplete block design, in-home interviews were conducted by trained personnel when infants were 2, 3, 4, 6, 8, 10, and 12 months of age; each mother/infant pair was seen four or five times. Information on food intake, including breast milk/formula, was collected at each interview. Means +/- SD and frequencies were calculated, and least squares analysis of variance was used to develop a predictive model related to the introduction of cereal.

RESULTS

Most mothers decided on the initial feeding mode (breastfeeding or formula) prior to pregnancy; 83% breastfed initially although most (76%) totally discontinued breastfeeding by 6 months. Infants' ages varied greatly when each of the seven categories of food was introduced, cereal was added to the infants' diets at a mean age of 3.8 +/- 1.4 (SD) months, juice 4.7 +/- 2.2, fruit 4.9 +/- 1.6, vegetables 5.2 +/- 1.3, mixed foods 7.8 +/- 2.1, table foods 8.2 +/- 2.1, and meat 8.2 +/- 2.1. The multivariate model explained 59% of the variability in ages of infants when cereal (generally the first solid food) was added. Significant variables (p < or = 0.05) were feeding mode, recommendation by the physician, and the interaction between feeding mode and education of the mother. Mother's employment and sibling rank of the infant contributed to the model (p = 0.06 and p = 0.09, respectively). Infants' age when cereal was added was not related to the variables of gender or birth weight.

CONCLUSIONS

The finding that the mothers' decision whether or not to breastfeed was made prior to conception supports the importance of population-based education aimed at women in the child-bearing years as well as patient instruction early in the pregnancy. However, the duration of breastfeeding was shorter than was reported in the 1980s. Infants varied greatly in ages when the seven categories of complementary foods were added to their diets. Although recommendations for delaying introduction of solid foods until the infant is 4 to 6 months of age have been in place for more than a decade, about half the mothers in this study did so earlier. Characteristics of mothers who introduced cereal earliest (i.e., mean age of infants < 4 months) were more likely to be formula feeding when cereal was added, to feed cereal via the bottle, to be primiparous, to be employed outside the home, and/or not to cite the physician as a source for guiding the infant's transition to supplemental food.

Surface-enhanced Raman gene probes

We report for the first time a new type of DNA gene probe based on surface-enhanced Raman scattering (SERS) label detection. The surface-enhanced Raman gene (SERG) probes do not require the use of radioactive labels and have great potential to provide both sensitivity and selectivity. The SERG probe can be used to detect DNA biotargets (e.g., gene sequences, bacteria, viral DNA fragments) via hybridization to DNA sequences complementary to that probe. The analytical figures of merit and its applications in environmental and biomedical areas are discussed.

Characterization of a novel tumor-derived cytokine. Endothelial-monocyte activating polypeptide II

Endothelial-monocyte activating polypeptide II (EMAP II) was initially identified in the supernatant of murine methylcholanthrene A-induced fibrosarcomas (Meth A) by its capacity to activate host effector cells (Kao, J., Ryan, J., Brett, J., Chen, J., Shen, H., Fan, Y-G., Godman, G., Familletti, P., Wang, F., Pan, Y-C., Stern, D., and Clauss, M. (1992) J. Biol. Chem. 267, 20239-20247). Based on the NH2-terminal protein sequence, a full-length cDNA has been cloned which indicates that the precursor of EMAP II is a unique, leaderless, single polypeptide chain with predicted molecular mass approximately 34 kDa and that the mature form released by Meth A cells corresponds to approximately 20 kDa. Purified recombinant mature EMAP II (EMAP II, approximately 20 kDa form) activated endothelial cells with resulting elevation of cytosolic free calcium concentration, release of von Willebrand factor, induction of tissue factor, and expression of the adhesion molecules E-selectin and P-selectin. Neutrophils exposed to EMAP II demonstrated elevated cytosolic free calcium concentration, peroxidase generation, and chemotaxis. EMAP II also activated mononuclear phagocytes elevating cytosolic free calcium concentration, inducing tumor necrosis factor-alpha (TNF) and tissue factor, and stimulating chemotaxis. Systemic infusion of EMAP II into C3H/HeJ or Balb/c mice was associated with systemic toxicity, pulmonary congestion, and the appearance of TNF, interleukin-1 and -6 in the plasma. A single intra-tumor injection of EMAP II into Meth A sarcomas induced acute thrombohemorrhage and partial tumor regression. Local injection of EMAP II into a tumor resistant to the effects of TNF, murine mammary carcinoma, rendered it sensitive to subsequently administered TNF, which resulted in acute thrombohemorrhage and partial regression. These data suggest that recombinant EMAP II, a tumor-derived cytokine, has properties of a proinflammatory mediator with the capacity to prime the tumor vasculature for a locally destructive process.

A peptide derived from the amino terminus of endothelial-monocyte-activating polypeptide II modulates mononuclear and polymorphonuclear leukocyte functions, defines an apparently novel cellular interaction site, and induces an acute inflammatory response

Endothelial-monocyte-activating polypeptide II (EMAP II) is a novel mediator isolated from conditioned medium of methylcholanthrene A-induced tumor cells which modulates properties of endothelial cells, mononuclear phagocytes (MPs), and polymorphonuclear leukocytes (PMNs) in vitro and induces an acute inflammatory response in vivo. A synthetic peptide comprising 15 residues from the N-terminal region (residues 6-20) was shown to induce directional migration of MPs and PMNs, with half-maximal effect at approximately 200-250 pM, whereas a peptide from the C terminus of EMAP II, as well as other irrelevant peptides, were without effect. Modulation of cellular phenotype by EMAP II-derived peptide was suggested by peptide-induced elevation of cytosolic free calcium concentration in fura-2-loaded MPs and PMNs and by stimulation of peroxidase release in PMNs. Consistent with these in vitro data, EMAP II-derived N-terminal peptide-albumin conjugates injected into the mouse footpad elicited inflammatory cell tissue infiltration, whereas albumin alone or EMAP II-derived C-terminal peptide conjugated to albumin incited little response. Binding of 125I-labeled EMAP II-derived peptide (residues 12-20) to MPs was saturable (Kd approximately 200 pM) and was blocked in a dose-dependent manner by the addition of intact EMAP II and unlabeled EMAP II-derived peptides (residues 6-20 and 12-20), whereas interleukin 1, tumor necrosis factor, formyl-methionyl-leucinyl-phenylalanine, or irrelevant peptides were without effect. Cross-linking of 125I-EMAP II-derived peptide (residues 12-20) by disuccinimidyl suberate to human MPs demonstrated a band, approximately 73 kDa, on reduced sodium dodecyl sulfate-polyacrylamide gel electrophoresis. 125I-EMAP II-derived peptide also demonstrated specific binding to human PMNs and murine RAW cells. These data indicate that the N-terminal region of EMAP II defines a biologically active locus of the molecule which interacts with target cells via a potentially novel cellular receptor.

The fms-like tyrosine kinase, a receptor for vascular endothelial growth factor

The fms-like tyrosine kinase (Flt) is a transmembrane receptor in the tyrosine kinase family. Expression of flt complementary DNA in COS cells conferred specific, high-affinity binding of vascular endothelial growth factor, also known as vascular permeability factor (VEGF-VPF), a factor that induces vascular permeability when injected in the guinea pig skin and stimulates endothelial cell proliferation. Expression of Flt in Xenopus laevis oocytes caused the oocytes to release calcium in response to VEGF-VPF. These findings show that flt encodes a receptor for VEGF-VPF.

The vascular endothelial growth factor proteins: identification of biologically relevant regions by neutralizing monoclonal antibodies

Angiogenesis plays critical roles in organ development during embryonic and fetal life, wound healing and in a variety of pathological conditions. Vascular endothelial growth factor (VEGF) is a secreted growth factor specific for vascular endothelial cells which induces angiogenesis in vivo. To gain a better understanding of the physiological role of VEGF, we have generated and characterized four murine monoclonal antibodies (mAbs) using the 165 amino acid species of recombinant human VEGF as immunogen. These mAbs (A3.13.1, A4.6.1, B4.3.1 and B2.6.2) belong to IgG1 isotype and have high affinities for VEGF (dissociation constants range from 2.2 x 10(-9) to 4 x 10(-10) M). Two different epitopes were detected with these mAbs. One epitope is recognized by mAbs A3.13.1 and B2.6.2, and the other recognized by mAbs A4.6.1 and B4.3.1. The epitope recognized by mAb A4.6.1 appears to be continuous while mAb B2.6.2 recognizes a discontinuous epitope. MAb A4.6.1 recognized three species of VEGF generated by alternative splicing, VEGF121, VEGF165 and VEGF189 while mAb B2.6.2 binds only VEGF165 and VEGF189. Results using an in vitro bovine adrenal cortex endothelial cell proliferation assay, in in vivo vascular permeability assay and an in vivo embryonic chicken angiogenesis assay showed that mAb A4.6.1 has potent VEGF neutralizing activities. MAb A4.6.1 was shown to block the binding of VEGF to its receptor(s) suggesting the inhibitory mechanism for VEGF activities. These well-defined mAbs should be very powerful tools to understand the structure-function relationship of various domains of VEGF and may have therapeutic potential.

Direct labeling of DNA-adducts formed from carcinogenic diol-epoxides with a fluorescent reporter compound specific for the cis vic-diol group

The fluorescent reporter group, N-(5-FLUORESCEINYL),N'-(3-BORONATOPHENYL)THIOUREA (FABA) has been synthesized. This boronate group makes the reporter specific for cis vic-diols. The reporter group is bound to DNA-adducts formed from the reaction of calf-thymus DNA and benzanthracene trans-10,11-dihydrodiol,8,9-epoxide (anti), benzo(a)anthracene-trans-3,4-dihydrodiol-1,2-epoxide (anti) but is not bound to 3-methylcholanthrene-11,12 dihydro-epoxide. Femtomole quantities of adduct may be detected.

Hepatopoietins A and B and hepatocyte growth

Serum from control or partially hepatectomized rats contains only two substances associated with stimulation of DNA synthesis in primary cultures of hepatocytes in serum free conditions. Hepatopoietin A is a large (105,000 kDa in monomeric form) heparin binding growth factor that is a heterodimer of two polypeptide chains (70,000 and 35,000 kDa). Another heparin binding growth factor, acidic FGF, also stimulates hepatocyte DNA synthesis but at a level comparable to half that of HPTA. These findings, along with recent observations of stimulation of liver growth and hepatoma formation in mice transgenic for the tat gene of the AIDS virus and overproducers of the heparin binding factor hst/KS3, raise the issue of the overall importance of different heparin binding growth factors in the control of hepatic growth regulation. Hepatopoietin B is a glycolipid that also acts as a complete hepatocytic mitogen. The role of the above substances as well as the role of norepinephrine, acting as a mitogenic trigger for stimulation of the rapid early phenomena associated with liver regeneration, is discussed.