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51.
Gabriela E. Leghi Merryn J. Netting Ching T. Lai Ardra Narayanan Michael Dymock Alethea Rea Mary E. Wlodek Donna T. Geddes Beverly S. Muhlhausler 《Nutrients》2021,13(6)
Maternal diet has the potential to affect human milk (HM) composition, but very few studies have directly assessed the effect of maternal diets on HM composition. The primary aim of this study was to assess the effect of improving dietary quality in lactating women over 2 weeks on the concentrations of macronutrients and metabolic hormones in HM. The secondary aims were to assess the impact of the dietary intervention on 24 h milk production, maternal body composition and infant growth. Fifteen women completed a 1-week baseline period followed by a 2-week dietary intervention phase targeted towards reducing fat and sugar intake. Maternal anthropometric and body composition and infant growth measurements were performed weekly. Total 24 h milk production was measured before and after the dietary intervention, and HM samples were collected daily. Maternal intakes of energy (−33%), carbohydrate (−22%), sugar (−29%), fat (−54%) and saturated fat (−63%) were significantly reduced during the dietary intervention. HM insulin, leptin and adiponectin concentrations were 10–25% lower at the end of the dietary intervention, but HM concentrations of macronutrients were unaffected. Maternal body weight (−1.8%) and fat mass (−6.3%) were significantly reduced at the end of the dietary intervention, but there were no effects on 24 h milk production or infant growth. These results suggest that reducing maternal energy, carbohydrate, fat and sugar intake over a 2-week period is associated with significant reductions in HM insulin, leptin and adiponectin concentrations. These changes may be secondary to decreases in maternal weight and fat mass. The limited studies to date that have investigated the association between metabolic hormone concentrations in HM and infant growth raise the possibility that the changes in HM composition observed in the current study could impact infant growth and adiposity, but further studies are required to confirm this hypothesis. 相似文献
52.
Michael B. Batz LaTonia C. Richardson Michael C. Bazaco Cary Chen Parker Stuart J. Chirtel Dana Cole Neal J. Golden Patricia M. Griffin Weidong Gu Susan K. Schmitt Beverly J. Wolpert Joanna S. Zablotsky Kufel R. Michael Hoekstra 《Emerging infectious diseases》2021,27(1):214
Foodborne illness source attribution is foundational to a risk-based food safety system. We describe a method for attributing US foodborne illnesses caused by nontyphoidal Salmonella enterica, Escherichia coli O157, Listeria monocytogenes, and Campylobacter to 17 food categories using statistical modeling of outbreak data. This method adjusts for epidemiologic factors associated with outbreak size, down-weights older outbreaks, and estimates credibility intervals. On the basis of 952 reported outbreaks and 32,802 illnesses during 1998–2012, we attribute 77% of foodborne Salmonella illnesses to 7 food categories (seeded vegetables, eggs, chicken, other produce, pork, beef, and fruits), 82% of E. coli O157 illnesses to beef and vegetable row crops, 81% of L. monocytogenes illnesses to fruits and dairy, and 74% of Campylobacter illnesses to dairy and chicken. However, because Campylobacter outbreaks probably overrepresent dairy as a source of nonoutbreak campylobacteriosis, we caution against using these Campylobacter attribution estimates without further adjustment. 相似文献
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55.
Mental Health of Mothers of Children with Juvenile Rheumatoid Arthritis: Appraisal as a Mediator 总被引:1,自引:3,他引:1
Lustig Julie L.; Ireys Henry T.; Sills Edward M.; Walsh Beverly B. 《Journal of pediatric psychology》1996,21(5):719-733
Examined direct and mediated relations between condition parametersand maternal mental health for 53 mothers of 2- to 11-year-oldchildren with juvenile rheumatoid arthritis (JRA). Multivariateanalyses revealed that when considered simultaneously, indicesof both biological severity and functional severity were associatedsignificantly with maternal mental health. Further, mother'sappraisals of the impact of the child's illness on the familypartially mediated the effects of medication type and child'sfunctional status on mother's mental health. Results providesupport for conceptual models that emphasize the cognitive mechanismsby which condition parameters such as biological and functionalseverity might affect maternal mental health. Explicating theprocesses by which a child's JRA might lead to psychologicaladjustment problems in the parent has implications for developingpreventive and treatment interventions. 相似文献
56.
Beverly A. Teicher Enrique Alvarez Sotomayor Zhen Dong Huang Gulshan Ara Sylvia Holden Vrinda Khandekar Ying-Nan Chen 《Cancer chemotherapy and pharmacology》1993,33(3):229-238
Tetrahydrocortisol, -cyclodextrin tetradecasulfate, and minocycline used alone or in combination are not very cytotoxic toward EMT-6 mouse mammary tumor cells growing in monolayer. Tetrahydrocortisol (100 M, 24 h) and -cyclodextrin tetradecasulfate (100 M, 24 h) protected EMT-6 cells from the cytotoxicity of CDDP, melphalan, 4-hydroperoxycyclophosphamide, BCNU, and X-rays under various conditions of oxygenation and pH. Minocycline (100 M, 24 h) either had no effect upon or was additive with the antitumor alkylating agents or X-rays in cytotoxic activity toward the EMT-6 cells in culture. The combination of the three modulators either had no effect upon or was to a small degree protective against the cytotoxicity of the antitumor alkylating agents or X-rays. The Lewis lung carcinoma was chosen for primary tumor growth-delay studies and tumor lung-metastases studies. Tetrahydrocortisol and -cyclodextrin tetradecasulfate were given in a 1:1 molar ratio by continuous infusion over 14 days, and minocycline was given i.p. over 14 days, from day 4 to day 18 post tumor implantation. The combination of tetrahydrocortisol/-cyclodextrin tetradecasulfate diminished the tumor growth delay induced by CDDP and melphalan and produced modest increases in the tumor growth delay produced by cyclophosphamide and radiation. Minocycline co-treatment increased the tumor growth delay produced by CDDP, melphalan, radiation, bleomycin, and, especially cyclophosphamide, where 4 of 12 animals receiving minocycline (14×5mg/kg, days 4–18) and cyclophosphamide (3×150 mg/kg, days, 7, 9, 11) were long-term survivors. The 3 modulators given in combination produced further increases in tumor growth delay with all of the cytotoxic therapies, and 5 of 12 of the animals treated with the 3-modulator combination and cyclophosphamide were long-term survivors. Although neither tetrahydrocortisol/-cyclodextrin tetradecasulfate, minocycline, nor the three modulator combination impacted the number of lung metastases, there was a decrease in the number of large lung metastases. Treatment with the cytotoxic therapies alone reduced the number of lung metastases. Addition of the modulators to treatment with the cytotoxic therapies resulted in a further reduction in the number of lung metastases. These results indicate that agents that inhibit the breakdown of the extracellular matrix can be useful additions to the treatment of solid tumors.Abbreviations 14(SO4)ßCD
-cyclodextrin tetradecasulfate
- THC
tetrahydrocortisol
- CDDP
cis-diamminedichloroplatinum(II)
- 4-HC
4-hydroperoxycyclophosphamide
- BCNU
N,N-bis(2-chloroethyl)-N-nitrosourea
- CAM
chick embryo chorioallantoic membrane; IC50, concentration of a drug required to kill 50% of the cells
This work was supported by NIH grant P01-CA38493 and a grant from Bristol-Myers-Squibb, Inc., Wallingford, Connecticut 相似文献
57.
The mechanisms involved in the recovery of body fat and liver metabolism after food restriction and refeeding are not understood. This study's aim was to determine the need for hepatic neural input for the compensatory changes in food intake, body composition and hepatic lipogenic enzymes seen upon realimentation after energy restriction. Rats underwent total surgical hepatic denervation or had sham operations. One group of sham-operated and denervated rats was fed a semipurified diet ad libitum; a second group was restricted to 40% ad libitum levels for 7 d, then given free access to food during a 2-d refeeding period. Body fat content and body fat recovery rate from below "set point" were not altered by hepatic denervation. These observations do not rule out liver involvement because blood-borne factors communicating energy status information to the central nervous system could be released from the liver. The activities of hepatic enzymes--glucose-6-phosphate dehydrogenase, malic enzyme and citrate cleavage enzyme--were stimulated at least twofold by restriction and refeeding when compared to ad libitum feeding. Hepatic denervation had no effect on basal enzyme levels in ad libitum-fed animals or on elevated enzyme activity induced by refeeding after food restriction. This study clearly demonstrates that hepatic innervation is not essential for energy balance and body composition regulation. The induction of lipogenic enzymes by food restriction and refeeding does not depend on central nervous system input to the liver. 相似文献
58.
Kang Shin Hong Sinhababu Achintya K. Cory Joseph G. Mitchell Beverly S. Thakker Dhiren R. Cho Moo J. 《Pharmaceutical research》1997,14(6):706-712
Purpose. This study is concerned with cellular delivery/generation of 2′-azido-2′-deoxyuridine and -deoxycytidine diphosphate (N3UDP or N3CDP), potent inhibitors of ribonucleotide reductase. It characterizes the phosphorylation steps involved in the conversion of 2′-azido-2′-deoxyuridine (N3Urd) and 2′-azido-2′-deoxycytidine (N3Cyd) to the corresponding diphosphates and explores a prodrug approach in cellular delivery of the inhibitor which circumvents the requirement of deoxynucleoside kinases. Methods. Cell growth of CHO and 3T6 cells of known deoxycytidine kinase level was determined in the presence of N3Urd and N3Cyd. Activity of ribonucleotide reductase was determined in the presence of the azidonucleosides as well as their mono- or di-phosphates in a Tween 80-containing permeabilizing buffer. A prodrug of 5′-monophosphate of N3Urd was prepared and its biological activity was evaluated with CHO cells as well as with cells transfected with deoxycytidine kinase. Results. N3Urd failed to inhibit the growth of both cell lines, while N3Cyd was active against 3T6 cells and moderately active against CHO cells. These results correlate with the deoxycytidine kinase levels found in the cells. Importance of the kinase was further established with the finding that the nucleoside analogs were inactive as reductase inhibitors in a permeabilized cell assay system while their mono- and di-phosphates were equally active. The prodrug was active in cell growth inhibition regardless of the deoxycytidine kinase level. Conclusions. The azidonucleosides become potent inhibitors of the reductase by two sequential phosphorylation steps. The present study indicates that the first step to monophosphate is rate-limiting, justifying a prodrug approach with the monophosphate. 相似文献
59.
Beverly A. Teicher 《Cancer metastasis reviews》1996,15(2):247-272
Conclusion The molecules described herein as antiangiogenic agents and antimetastatic agents represent a wide variety of molecular structures with a wide variety of biological effects and targets. Most often these agents have been generally classified as antiangiogenic or antimetastatic by their effects in an in vitro bio-assay system. The diversity in this group of molecules gives strength to the potential of this approach in therapeutic applications. The biological and biochemical pathways involved in angiogenesis are numerous and redundant. It is likely that there are many angiogenic factors and many pathways of invasion, therefore it is likely that blockade of more than one pathway related to angiogenesis and/or invasion will be necessary to impact on the natural progress of a malignant disease.The vasculature forms the first barrier to penetration of molecules into tumors. Although the antiangiogenic agent treatments administered in this study did not inhibit angiogenesis in these tumors completely, the vasculature present in the treated tumors may be impaired compared to control tumors. Overall, therefore, the best speculation is that the main targets for the antiangiogenic agents are extracellular matrix processes and/or tumor endothelial cells and that inhibition and/or impairment of these non-malignant functions can improve therapeutic responses when used in combination with cytotoxic therapies. The incorporation of antiangiogenic agents and/or antimetastatic agents into therapeutic regimens represents an important challenge. The successful treatment of cancer requires the eradication of all malignant cells and therefore treatment with cytotoxic therapies. The compatibility of antiangiogenic therapy and/or anti-invasion agents with cytotoxic chemotherapeutic agents is not obvious [316].The goal of the addition of any non-cytotoxic potentiator to a therapeutic regimen is to take a good therapy and, without additional toxicity, push it to cure.Cyclophosphamide is a good drug against the Lewis lung carcinoma although no long-term survivors of animals bearing Lewis lung carcinoma are achieved with cyclophosphamide treatment alone. Adding antiangiogenic agents to treatment of this tumor with cyclophosphamide produced a cure rate of 40–50%, meaning that both the primary and metastatic disease has been eradicated in these animals. Cures were achieved only when the antiangiogenic treatments extended from days 4–18 post Lewis lung tumor implantation. The results obtained with the addition of antiangiogenic agents to cytotoxic anticancer therapies in in vivo models of established solid tumors have been very positive and provide direction for future clinical trials including these antiangiogenic agents. Two conclusions may be drawn. First, combinations of antiangiogenic and/or antimetastatic agents evoke a greater effect on tumor response to therapy than does treatment with single agents of these classes. Second, treatment with antiangiogenic agents and/or antimetastatic agents can interact in a positive way with cytotoxic therapies. 相似文献
60.
D M Hays R B Raney W Lawrence M Tefft E H Soule W M Crist M Foulkes H M Maurer 《Journal of pediatric surgery》1982,17(6):812-820
Twenty-nine children (24, male; 5, female) with non-disseminated rhabdomyosarcomas of the bladder or prostate were treated (1978-1980) by a primary chemotherapy regimen consisting of vincristine, actinomycin D, and cyclophosphamide ("Pulse" VAC), with or without local radiotherapy. During the initial 20 wk of chemotherapy, nine children achieved a Clinical Complete Response (CCR). Three of these are without evidence of disease (NED) and have functional bladders, two following partial cystectomy. Four who achieved a CCR subsequently relapsed or remained biopsy positive, but are at present NED following radiotherapy and anterior exenteration. Two patients who achieved CCR status relapsed and have died of disease. Twelve patients had a Clinical Partial Response (CPR) in less than 20 wk and two others in less than 40 wk. Seven of these are NED with intact bladders following chemotherapy-radiotherapy; and an additional patient is NED following partial cystectomy. Four patients in the CPR group have been treated by exenteration following failure to achieve complete response, and are NED. One patient has died, and one has progressive disease. Six patients had an inadequate response to chemotherapy (NR). Anterior exenteration was carried out in three, and two of these have survived. The overall results in these 29 patients are: (A) alive and disease-free with functional bladders, 11; (B) alive and disease-free following anterior exenteration, 10; and (C) dead or death from tumor anticipated, 8. The function of retained bladders (11) has been satisfactory. 相似文献