Milk Bank Pooling Practices Impact Concentrations and Variability of Bioactive Components of Donor Human Milk.

Donor human milk (DHM) bank practices, such as pasteurization and pooling according to postpartum age of milk donations and number of donors included in a pool may impact the resulting concentration of bioactive components of DHM. We determined the impact of Holder pasteurization, postpartum milk age, and pool donor number (number of donors included in a pool) on resulting concentrations of total immunoglobulin A (IgA; which provides immune protection to the recipient infant) and insulin (an important hormone for gut maturation).We also documented inter-relationships between these bioactive components and macronutrients in DHM pools.

Effect of Pooling Practices and Time Postpartum of Milk Donations on the Energy, Macronutrient, and Zinc Concentrations of Resultant Donor Human Milk Pools.

Objective: To characterize the macronutrient, energy, and zinc composition of pasteurized donor human milk pools and evaluate how composition varies based on pooling practices and "time postpartum" (ie, elapsed time from parturition to expression date) of individual milk donations.

Study Design: The Mothers' Milk Bank (Arvada, Colorado) donated 128 donor human milk pools. Caloric density was assessed via mid-infrared spectroscopy, and zinc concentration was measured by atomic absorption spectroscopy.

The urban homeless: super-users of the emergency department.

In the United States, patient usage of costly emergency departments (EDs) has been portrayed as a major factor contributing to health care expenditures. The homeless are associated with ED frequent users, a population often blamed for inappropriate ED use. This study examined the characteristics and costs associated with homeless ED frequent users.

Syntheses and biological evaluation of vinblastine congeners.

Sixty-two congeners of vinblastine (VLB), primarily with modifications of the piperidine ring in the carbomethoxycleavamine moiety of the binary alkaloid, were synthesized and evaluated for cytotoxicity against murine L1210 leukemia and RCC-2 rat colon cancer cells, and for their ability to inhibit polymerization of microtubular protein at < 10(-6) M, and for induction of spiralization of microtubular protein, and for microtubular disassembly at 10(-4) M concentrations. An ID50 range of >10(7) M concentrations was found for L1210 inhibition by these compounds, with the most active 1000x as potent as vinblastine.

Syntheses of 5a'-homo-vinblastine and congeners designed to establish structural determinants for isolation of atropisomers.

The syntheses of 5a'-homo-vinblastine (3a) and its C-20' methyl congener 62a were achieved. In contrast to vinblastine, these compounds did not allow isolation of atropisomers because of their lower conformational inversion barrier. However, annelation of a six-membered ring to the conformationally mobile D'-piperidine ring provided an isolated atropisomer 81a, which could be converted to its lower energy conformation 65a on heating.

Modulation of drug cytotoxicity in wild-type and multidrug-resistant tumor cells by stereoisomeric series of C-20'-vinblastine congeners that lack antimicrotubule activity.

Seven binary vinca alkaloid congeners were newly synthesized as the C14' or C16'(20') or C14'16'(20') stereoisomers of C20'-modified VBL. These congeners lacked detectable antimicrotubule activity in assays of polymerization of purified microtubule protein and of mitotic arrest induction. The compounds modulated the cytotoxicity of VBL, VCR, and DOX in sarcoma and colon-tumor cell lines.

Nutritional folate-deficiency in Chinese hamster ovary cells. Chromosomal abnormalities associated with perturbations in nucleic acid precursors.

Folate deficiency is known to induce chromosomal abnormalities. We used a nutritionally folate-deficient Chinese hamster ovary (CHO) cell culture system to examine modulation of chromosome damage by purine or pyrimidine supplementation. The cells were cultured in folate-deficient (Fol-) medium or Fol- medium supplemented with thymidine (dT) or hypoxanthine (Hx) until population growth arrest.

Nutritional folate deficiency in Chinese hamster ovary cells. I. Characterization of the pleiotropic response and its modulation by nucleic acid precursors.

Nutritional folate deficiency in Chinese hamster ovary (CHO)-K1 cells inhibited population growth rate and caused growth arrest within 3 days of culture in Fol- medium [without folate, hypoxanthine (Hx), and thymidine (TdR)]. Coincident with impaired population growth was a transient delay in cell cycle progression through S phase and an increase in cell size. The growth-arrested population of predominantly G1 phase cells exhibited an increased adhesion to the culture substratum.

Specific alterations in the biological activities of C-20'-modified vinblastine congeners.

Both the anti-tumor and toxic activities of the vinca alkaloid dimers, vinblastine (VBL) and vincristine (VCR), may reside at the level of their known cellular target, the microtubule system. The contributions made by each of the various actions of these alkaloids on this system are unknown. We have used new, complete synthetic methodologies to create a series of eight C-20' alkyl congeners of VBL and have examined these compounds for their abilities to (1) inhibit microtubule assembly, (2) disassemble preformed microtubules, and (3) induce spiral aggregate formation, using purified brain microtubule protein.

Single site-modified congeners of vinblastine dissociate its various anti-microtubule actions.

New C-20' alkyl congeners of vinblastine (VBL) were examined for their reaction with purified microtubule protein or steady-state microtubules in vitro. We found that each of the three typical activities of VBL with this system was amenable to alteration through structural modification of the molecule at this single site. The activity profiles were congener-specific, and they establish the dissociable nature of the various actions that characterize the parent molecule, VBL.

Epilepsy self-help groups: collaboration with professionals.

Two sequential cases of professional-self-help/mutual aid collaboration are described. The first was a federally funded demonstration project to develop epilepsy self-help groups in 15 cities. It involved a "mixed strategy" of national and local collaboration, where decision-making, and problem solving was vested in persons with epilepsy.

Establishment of two parental cell lines and three clonal cell strains from rat colonic carcinoma.

Two epithelial cell lines were established from separate pools of cells that were harvested by a sequential proteolytic treatment of a single specimen of rat transplantable colonic carcinoma. The cells were small (10-micrometer diameter) and cuboidal and displayed desmosomes and light junctions. Both cell lines grew rapidly with population-doubling times of 20 to 22 hr, were near diploid in chromosome number, contained A-2 and B-7 marker chromosomes, and were tumorigenic in rats.

Modulation of mammalian cell growth by a choline analog, N-isopropylethanolamine.

The choline analog, N-isopropylethanolamine (IPE), inhibits the growth of both Chinese hamster ovary CHO-K1 and mouse L-M cells by two kinetically distinct mechanisms; I, a reversible and concentration-dependent reduction in the logarithmic population doubling rate and the saturation density of cultures by low IPE levels in the media; and II, an irreversible and time-dependent killing of cells by high IPE concentrations. Both types of inhibition are independent of media depletion, cell density, or the time of treatment after cell plating; however, the actual IPE concentration that is necessary to elicit Type I or Type II inhibition in each cell line is dependent on the choline level of the media. Ethanolamine, methionine, or betaine have no effect on IPE-induced growth inhibition.