Breast cancer and reduction mammoplasty: the role of routine pre-operative mammography.

Occasionally breast cancer is accidentally discovered in specimens from patients undergoing reduction mammoplasty. We present the cases of two patients, both over 50 years of age. Because a reduction mammoplasty distorts the architecture of the breast, the post-operative discovering of a carcinoma renders mastectomy the only treatment option possible. We recommend the use of a pre-operative mammography for all women over 50 years of age who are scheduled for a breast reduction.

Dietary citrulline but not ornithine counteracts dietary arginine deficiency in rats by increasing splanchnic release of citrulline.

Ornithine and citrulline have different arginine-sparing capabilities when provided in an arginine-deficient diet. Rats were fed arginine-deficient diets containing ornithine or citrulline to see the effect on net fluxes of free arginine, ornithine and citrulline across the portal-drained viscera (PDV) and liver. The diets contained either 10 g arginine/kg diet (+Arg) or no arginine: the -Arg/+Ala diet contained additional alanine and the -Arg/+Orn and -Arg/+Cit diets contained ornithine and citrulline, respectively, in amounts isomolar to the amount of arginine in the control (+Arg) diet. Blood arginine concentrations were 50% lower than control values (P < 0.001) in rats fed the -Arg/+Ala or the -Arg/+Orn diet. However, addition of citrulline to the arginine-deficient diet restored blood arginine concentrations. The source of the circulating arginine in the rats fed the -Arg/+Cit diet was neither the PDV nor the liver; net splanchnic uptake of arginine was 0.3 mumol/min. Net citrulline release was substantial from the PDV (0.65 mumol/min) as well as from the splanchnic bed (0.67 mumol/min) of rats fed the -Arg/+Cit diet, such that blood citrulline concentrations were more than double (P < 0.001) those in rats fed the +Arg or -Arg/+Orn diet. Splanchnic release of citrulline in rats fed the -Arg/+Cit diet but not in rats fed the -Arg/+Orn diet supported the production of arginine in non-splanchnic organs such as, presumably, the kidney.

Supplemental arginine and ornithine do not affect splenocyte proliferation in surgically treated rats.

The present study was designed to determine whether arginine or ornithine supplementation enhanced immune responsiveness in surgically stressed rats. Young rats (130 to 150 g; n = 72) were fed one of three nonpurified diets: control, arginine-supplemented (30 g/kg of diet), or supplemented with ornithine on an equimolar basis to supplemental arginine. Control and ornithine-supplemented diets were made isonitrogenous to the arginine-supplemented diet with alanine. Food intake and body weight were monitored throughout the experimental period. Eight days after initiation of dietary treatments, 36 rats were given dorsal skin wounds. Rats were killed 7 days later. Blood was collected, spleen and thymus were weighed, and splenocytes were isolated to measure proliferation in response to mitogens and interleukin-2 production. Food intake, body weight gain, and thymus weight were lower in rats subjected to surgery than in controls rats (p < .01). Neither supplemental dietary arginine nor ornithine affected food intake, body weight gain, thymus weight, splenocyte proliferation, or splenocyte interleukin-2 production in any treatment group (p < .1). These data suggest that low-level dietary supplementation of arginine and ornithine did not ameliorate detrimental effects of minor surgery in rats.

Influence of recombinant bovine somatotropin (sometribove) on mononuclear cells during the nonlactating period.

Recombinant bST was evaluated as a potential immunoenhancer of bovine peripheral blood and mammary gland mononuclear cells during the nonlactating period. Cows (n = 4 per group) were assigned to one of four treatments: 1) untreated, 2) treated with recombinant bST during lactation only, 3) treated with recombinant bST during the nonlactating period only, and 4) treated with recombinant bST during lactation and the nonlactating period. Recombinant bST treatment during the nonlactating period had no effect on proliferation of bovine blood or mammary gland mononuclear cells in response to stimulation by mitogens or allogeneic cells. Recombinant bST treatment during the nonlactating period enhanced interleukin-2 secretion by mononuclear cells isolated from cows treated also with recombinant bST during lactation. However, recombinant bST treatment during the nonlactating period had little effect on interleukin-2 secretion by mononuclear cells from cows not treated with recombinant bST during lactation. Results of this study suggest that recombinant bST alters effector functions rather than proliferation of bovine mononuclear cells.

Oral arginine supplementation does not affect lymphocyte proliferation during endotoxin-induced inflammation in rats.

Earlier studies from this laboratory were unable to confirm reported immunostimulatory effects of supplemental dietary arginine on healthy, unstressed young or aged rats. The present study was undertaken to determine effects of oral arginine supplementation on in vitro measures of immune function using a stressed rat model. The stressor used was intraperitoneal injection of bacterial lipopolysaccharide (1 mg/kg body wt). Four-month-old male Sprague-Dawley rats were placed in either a control or an arginine-supplemented (7.5 g/L arginine-HCl in drinking water) group for 7 d, after which control and supplemented rats received injections of endotoxin or phosphate-buffered saline. Rats were killed 3 d following injections. Endotoxin treatment resulted in lower food intake, less thymic cellularity and greater splenic weight. Endotoxin injections also enhanced proliferative response of rat splenocytes to pokeweed mitogen (1 mg/L) and lipopolysaccharide (25 and 100 mg/L) and enhanced response of thymocytes to concanavalin A (10 mg/L), phytohemagglutinin (25 and 100 mg/L) and pokeweed mitogen (1 mg/L). Supplemental arginine did not reduce thymic weight loss or influence mononuclear cell proliferation or interleukin-2 production in the presence or absence of endotoxin stress. These data indicate no benefit of arginine supplementation during endotoxin stress in rats.

Proliferative response of mammary gland mononuclear cells to recombinant bovine interleukin-2.

Methods of augmenting bovine mononuclear cell responsiveness during physiological transitions of the udder may enhance resistance of the mammary gland to intramammary infections. Interleukin-2 is required for proliferation of T-lymphocytes and may contribute to B-lymphocyte proliferation. Recombinant bovine interleukin-2 (rBoIL-2) was evaluated as a potential immunoenhancer of bovine mammary gland mononuclear cells. Bovine mononuclear cells were isolated from five primiparous Holstein cows at 14-18 and 28-32 days of involution and at 7-13 days prior to parturition. Bovine blood and mammary gland mononuclear cells were highly responsive to rBoIL-2. Response of mammary gland mononuclear cells to rBoIL-2 was comparable with response of blood mononuclear cells. These data suggest that rBoIL-2 may be an effective immunoenhancer of bovine mononuclear cells during the non-lactating and prepartum periods.

Modulation of bovine mononuclear cell proliferation during physiological transitions of the mammary gland.

Mammary secretions and blood were collected from five primiparous Holstein cows 14 d following cessation of milking and 14 d prior to parturition for preparation of serum and mammary secretion skim fractions. Mammary secretions and blood were collected from the same animals 15 to 18 d following cessation of milking and 2 to 13 d prior to parturition for isolation of mononuclear cells. Effects of serum on mammary gland mononuclear cell proliferation and skim fractions from mammary secretions on blood mononuclear cell proliferation were evaluated. Mononuclear cell proliferation was evaluated in a mitogen-induced lymphocyte proliferation assay and in a mixed leukocyte assay. Proliferative responses of blood and mammary gland mononuclear cells did not vary significantly between the two time periods evaluated. Mammary secretion skim fractions obtained at both time periods significantly suppressed blood mononuclear cell proliferation. In contrast, exogenous serum enhanced mammary gland mononuclear cell proliferation in response to mitogens and allogeneic cells. Ability to enhance in vitro proliferation of mammary mononuclear cells isolated during physiological transitions of the mammary gland may suggest the potential for enhancing mammary mononuclear cell proliferation in vivo to reduce incidence of new intramammary infections at times when the mammary gland is highly susceptible.

Interleukin-2 secretion by bovine mammary gland mononuclear cells during the nonlactating period.

Bovine blood and mammary gland mononuclear cells were isolated from five primiparous Holstein cows at 14-18 and 28-32 days of involution and 7-13 days prior to parturition and used in a bioassay to determine if bovine mammary mononuclear cells produced interleukin-2 in culture. Interleukin-2 production by mononuclear cells was stimulated in 24 hr cultures using concanavalin A. Bovine interleukin-2 dependent cytotoxic T-lymphocytes were used as target cells. Interleukin-2 production by mammary gland and blood mononuclear cells was comparable. Interleukin-2 production by mammary gland mononuclear cells did not vary significantly over the three time periods evaluated. However, blood mononuclear cells isolated at 28-32 days of involution produced significantly greater amounts of interleukin-2 compared to blood mononuclear cells isolated during the early nonlactating period and the prepartum period. These data suggest that bovine mononuclear cell hyporesponsiveness to mitogens during the nonlactating period is not due to a deficiency in interleukin-2 production.

Efficacy of chlorhexidine as a postmilking teat disinfectant for the prevention of bovine mastitis during lactation.

A natural exposure trial was conducted for 12 mo in a herd of 150 lactating Jersey cows to determine efficacy of a .35% chlorhexidine teat dip containing a glycerine emollient for the prevention of bovine intramammary infections. Right teats of cows were dipped in the experimental teat dip after milking machine removal and left teats were not dipped. The herd was free of Streptococcus agalactiae and had a low prevalence of Staphylococcus aureus. Most new major pathogen intramammary infections resulted from Streptococcus species, primarily Streptococcus uberis and Streptococcus dysgalactiae. New infections by Streptococcus species were significantly lower in teats dipped in chlorhexidine than in undipped teats. Overall efficacy of the chlorhexidine teat dip against major mastitis pathogens was 50%. The experimental teat dip also reduced coagulase-negative Staphylococcus species infections 49.0% and Corynebacterium bovis infections 65.2%. Overall efficacy against minor mastitis pathogens was 54.0%. No irritation or chapping of teats dipped in the experimental teat dip was observed.

Prevention of bovine mastitis by a postmilking teat disinfectant containing chlorous acid and chlorine dioxide in a soluble polymer gel.

A natural exposure study was conducted in a herd of 150 lactating dairy cows for 18 mo to determine the effectiveness of chlorous acid and chlorine dioxide in a soluble polymer gel as a postmilking teat disinfectant for the prevention of bovine mastitis. Right quarters of cows were dipped in the experimental teat dip after milking machine removal. Left quarters were not dipped and served as within-cow negative controls. The experimental teat dip reduced Staphylococcus aureus infections 67.4%, Streptococcus dysgalactiae infections 63.8%, and Streptococcus uberis infections 27.8%. Overall efficacy of the chlorous acid and chlorine dioxide teat dip against major mastitis pathogens was 52.2%. The experimental teat dip reduced Corynebacterium bovis infections and coagulase-negative staphylococcal infections also by 45.8 and 38.7%, respectively. Overall efficacy against minor mastitis pathogens was 43.4%. Under conditions of this trial, the experimental teat dip containing chlorous acid and chlorine dioxide was effective in preventing new intramammary infections against a variety of mastitis pathogens.

Inhibition of bovine peripheral blood mononuclear cell blastogenesis by fractionated mammary secretion.

1. Bovine mammary secretion whey obtained during late involution markedly inhibited mitogen-induced blood mononuclear cell blastogenesis. 2. Whey proteins eluting in the first and second absorbance peaks following molecular exclusion chromatography were associated with greatest inhibition of mononuclear cell blastogenesis. 3. Greatest inhibition of concanavalin A-stimulated mononuclear cell blastogenesis was associated with high concentrations of whey proteins in absorbance peak 1. 4. Whole mammary secretion whey and whey proteins in absorbance peak 2 caused similar inhibition of concanavalin A- and phytohaemagglutinin-treated mononuclear cells. 5. Differential inhibition of mitogen-induced blastogenesis may reflect the presence of immunosuppressive substances in bovine mammary secretion whey which differ in specificity for bovine T-cell subsets.

Suppression of mitogenic response of peripheral blood mononuclear cells by bovine mammary secretions.

Effects of bovine mammary secretions collected at different stages of the lactation cycle on blood mononuclear cell response to mitogens were evaluated. Mammary secretion skims and wheys collected 7 and 28 d following cessation of milking, at parturition, and during early lactation were used. Colostrum and mammary secretions obtained 7 d after milk cessation were associated with greatest inhibition of mononuclear cell blastogenesis. Milk collected during early lactation caused the least inhibition. Mammary secretion wheys caused greater inhibition of blastogenesis than skims. Dilution of mammary secretions reduced blastogenic inhibition. Phytohemagglutinin-stimulated mononuclear cells were less inhibited by mammary secretion than Concanavalin A-stimulated cells. Suppression of mononuclear cell activity, particularly during early involution and at parturition, may influence susceptibility of the bovine mammary gland to new intramammary infections during physiological transitions of the udder.

Changes in blastogenic activity of bovine blood mononuclear cells throughout the nonlactating period.

Mononuclear cells were isolated from bovine blood by density gradient centrifugation to determine variation in mitogen-induced mononuclear cell activity throughout the nonlactating period. In a preliminary study, optimum concentrations of Concanavalin A, phytohemagglutinin, Salmonella typhimurium lipopolysaccharide, and three Escherichia coli lipopolysaccharides were determined using six cows as blood donors. Concanavalin A, phytohemagglutinin, and E. coli 0111:B4 lipopolysaccharide were selected for further studies. Mitogenic responses of blood mononuclear cells from five cows were evaluated at drying off, 14 to 16 and 28 to 30 d of involution, 12 to 14 d prepartum, and at parturition. Concanavalin A-treated cells exhibited greater blastogenic activity than phytohemagglutinin-treated cells. Response of cells to Concanavalin A increased slightly through 28 to 30 d of involution and decreased markedly at parturition. Blastogenic activity of cells treated with phytohemagglutinin decreased throughout the nonlactating period and was lowest at parturition. Activity of lipopolysaccharide-treated mononuclear cells increased through 28 to 30 d of involution. However, response of mononuclear cells to lipopolysaccharide was minimal compared with response to Concanavalin A and phytohemagglutinin. Variation in peripheral blood mononuclear cell activity throughout involution may parallel mammary gland mononuclear cell activity, affecting susceptibility of the mammary gland to new intramammary infections.