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1.
Subst Use Misuse ; 56(11): 1707-1714, 2021.
Article in English | MEDLINE | ID: mdl-34253161

ABSTRACT

OBJECTIVE: Cigarette smoking is inversely associated with education, and despite this gradient effect, individuals with a General Educational Development (GED) diploma, obtained through a high school equivalency test, have the highest smoking prevalence. Considered the high school equivalency credential, it is unclear why individuals with a GED have a substantially higher smoking prevalence compared to high school graduates and dropouts. We conducted a qualitative study to understand life experiences, tobacco use patterns, and perceptions of tobacco among GED smokers and attitudes and behaviors around smoking cessation. METHODS: We recruited 40 GED smokers aged 18 to 35 years and conducted surveys and semi-structured individual interviews. Transcripts were independently coded, then coding differences were resolved and reviewed by a third team member. We independently determined themes within and between codes and met to determine final themes. RESULTS: GED recipients had many early life experiences and characteristics that made them highly vulnerable to tobacco dependence. With perceived high cognitive abilities, GED smokers were knowledgeable of many evidence-based smoking cessation strategies and were aware of health risks. Health risks and the financial burden of smoking were motivation to quit. The majority were uninterested or lacked confidence that nicotine replacement therapy, medications, counseling, or the quitline could help them quit. Nearly all were enthusiastic and confident that financial incentives had the potential to help them quit. CONCLUSIONS: Research is needed to determine whether financial incentives could improve smoking cessation outcomes in this unique population with an unequal burden of smoking.


Subject(s)
Smoking Cessation , Humans , Motivation , Smokers , Smoking , Tobacco Use Cessation Devices
2.
BMJ Open ; 6(6): e011053, 2016 06 06.
Article in English | MEDLINE | ID: mdl-27266774

ABSTRACT

OBJECTIVES: Electronic nicotine delivery systems (ENDS) have recently emerged as a component of the tobacco retail environment. The aims of this study were to describe the availability, types of ENDS and placement of ENDS relative to traditional tobacco products at franchised licensed tobacco retailers and non-franchised licensed tobacco retailers. DESIGN: Observational study. SETTING: Franchised and non-franchised tobacco retailers in Cleveland County, Oklahoma, USA. PRIMARY AND SECONDARY OUTCOME MEASURES: The number of stores selling ENDS, the variability in brands of ENDS sold, the location of the ENDS within the retailers, the quantity of ENDS sold compared with traditional tobacco products, and the presence of outdoor signage. RESULTS: Data from 57 randomly sampled tobacco retailers were used to describe the presence of ENDS at independent non-franchised and franchised tobacco retailers. The overwhelming majority (90%) of licensed tobacco retailers sold ENDS, and differences were observed between franchised and non-franchised stores. 45 of the 51 retailers (88%) selling ENDS had them placed at the point of sale. 2 of the 21 franchised retailers (9.5%) had ENDS placed at ≤3½ feet above floor level compared to none of the 30 non-franchised retailers (0%). CONCLUSIONS: This small study is the first to characterise ENDS within the tobacco retail environment in a county in Oklahoma, USA. The results from this study demonstrate the complexity of the tobacco retail landscape and generate questions for future studies regarding the incorporation and placement of ENDS in tobacco retail environments.


Subject(s)
Commerce/statistics & numerical data , Electronic Nicotine Delivery Systems/classification , Electronic Nicotine Delivery Systems/statistics & numerical data , Licensure , Oklahoma , Surveys and Questionnaires , Tobacco Products
3.
Theriogenology ; 75(8): 1453-8, 2011 May.
Article in English | MEDLINE | ID: mdl-21220168

ABSTRACT

The objective was to develop a simple successful porcine cryopreservation protocol that prevented contact between embryos and liquid nitrogen, avoiding potential contamination risks. In vivo-derived blastocysts were collected surgically from donor pigs, and two porcine embryo vitrification protocols (one used centrifugation to polarize intracytoplasmic lipids, whereas the other did not) were compared using the Cryologic Vitrification Method (CVM), which used solid surface vitrification. The CVM allowed embryos to be vitrified, without any contact between embryos and liquid nitrogen. Both protocols resulted in similar in vitro survival rates (90% and 94%) and cell number (89 ± 5 and 99 ± 5) after 48 h in vitro culture of vitrified and warmed blastocysts. The protocol that did not use centrifugation was selected for continued use. To protect vitrified embryos from contact with liquid nitrogen and potential contamination during storage, a sealed outer container was developed. Use of this sealed outer container did not affect in vitro survival of cryopreserved blastocysts. In vivo blastocysts (n = 151) were collected, vitrified, and stored using the selected protocol and sealed container. These embryos were subsequently warmed and transferred to six recipients; five became pregnant and farrowed a total of 26 piglets. This embryo vitrification method allowed porcine embryos to be successfully vitrified and stored without any contact with liquid nitrogen.


Subject(s)
Blastocyst/physiology , Cryopreservation/methods , Embryo Transfer/methods , Fertilization in Vitro/veterinary , Swine/physiology , Animals , Culture Techniques , Female , Male , Pregnancy
4.
Cloning Stem Cells ; 9(2): 206-15, 2007.
Article in English | MEDLINE | ID: mdl-17579553

ABSTRACT

As the pig becomes increasingly used for biomedical research, an effective and efficient in vitro culture system is essential. This study aimed to improve the commonly used porcine embryo culture medium, NCSU23, by altering the energy substrates and adding amino acids, using electrically activated diploid parthenotes from oocytes obtained from the ovaries of prepubertal and adult animals. Morphological development to day 6 and blastocyst cell number were examined. Glucose (5.56 mM) was replaced by pyruvate and lactate (0.2 mM and 5.7 mM, respectively) for either the entire culture period or for the first 48 h only. Blastocyst rates were not different between any of the treatments, and were similar for prepubertal and adult oocytes. When the embryos were cultured with pyruvate and lactate for the first 48 h and then glucose, there was a significant increase in blastocyst cell number compared to glucose only. Blastocysts produced using pyruvate and lactate for the entire time tended to have more cells than those exposed to glucose only and less than those who were cultured in pyruvate and lactate for the first 48 h and then glucose. Nonessential amino acids added for the first 48 h and nonessential and essential amino acids added for the remaining time significantly increased blastocyst cell number only when the embryos were grown in pyruvate and lactate followed by glucose. Blastocyst rates were not different between any of the treatments, and this result was the same when using sow or gilt oocytes. The modified medium was then tested using in vitro matured and fertilized embryos from sow oocytes. Blastocyst rates and cell number were significantly increased in the modified medium compared to those grown in unmodified NCSU23. This shows that altering energy substrates and adding amino acids can increase the quantity and cell number of IVP blastocysts compared with NCSU23.


Subject(s)
Amino Acids/pharmacology , Blastocyst/cytology , Animals , Blastocyst/drug effects , Cells, Cultured , Culture Media/chemistry , Female , Fertilization in Vitro , Glucose/pharmacology , Lactates/pharmacology , Male , Pyruvates/pharmacology , Sus scrofa/embryology
5.
Soc Reprod Fertil Suppl ; 62: 277-91, 2006.
Article in English | MEDLINE | ID: mdl-16866324

ABSTRACT

Recent advances in cryopreservation and non-surgical transfer of pig embryos have made embryo transfer in pigs a commercially viable technology especially for the international transfer of valuable genetic material. Early research demonstrated that early stage pig embryos were highly sensitive to temperatures below 15 degrees C and this sensitivity decreased with development to peri-hatching blastocysts which is accompanied by a reduction in lipid content. Removal of the lipid prior to freezing was found to improve the freezability and resulted in the birth of piglets. It was shown that by polarising the lipid material out of the blastomeres and using ultra rapid freezing (vitrification) the early stage zona pellucida intact embryo would also survive freezing and result in the birth of piglets. Other factors that have contributed to successful cryopreservation of the early stage pig embryo include the use of cytoskeletal stabilising agents, specific cryoprotectants, increasing cooling rates using open pulled straws or micro droplets and assisted hatching. The present review discusses the relative importance of each of these factors. The development of non-surgical transfer technology and its importance in the application of embryo transfer in the pig industry is also reviewed.


Subject(s)
Cryopreservation/methods , Embryo Transfer , Embryo, Mammalian , Sus scrofa , Animals , Breeding , Cryoprotective Agents , Female , Genotype , Pregnancy , Pregnancy Rate
6.
Theriogenology ; 64(4): 879-90, 2005 Sep 01.
Article in English | MEDLINE | ID: mdl-16054493

ABSTRACT

The objective was to improve the protocol that was used to obtain the first reported piglets from transferred vitrified and warmed zona-intact blastocysts. Blastocysts were collected from superovulated sows and gilts, centrifuged to polarize lipid, vitrified, warmed and cultured for 24h or transferred immediately. Removing the zona pellucida after warming increased the number of cells in the surviving blastocysts (zona-free 60.8+/-4.3, zona-intact 39.1+/-2.8; P<0.05). Thinning the zona pellucida produced similar results to zona removal. Changing the basal medium of the vitrification and warming solutions from modified PBS to phosphate buffered NCSU-23 increased the number of cells (44.7+/-2.2 versus 56.0+/-3.9, respectively; P<0.05). Reducing the plunge temperature of the liquid nitrogen from -196 degrees C to less than -204 degrees C improved the embryo survival rate (61.9% versus 82.9%, respectively; P<0.05). These modifications were incorporated into the vitrification protocol that was used to vitrify and warm 105 blastocysts (that were subsequently transferred into four recipients). Three recipients became pregnant, farrowing three litters (average litter size, 5.3; 18.8% embryo survival in farrowing sows). Changing the warming protocol to using sucrose rather than ethylene glycol resulted in a trend towards improved embryo survival (73.5% versus 91.2%) but this was not statistically significant. Incorporating this modification, 203 blastocysts were vitrified, warmed and transferred into seven recipients. Five became pregnant and 36 fetuses were recovered (average litter size 7.2; 24.8% embryo survival in pregnant sows) at Day 40 of pregnancy. In conclusion, changes made to the vitrification protocol improved pregnancy rate and in vivo embryo survival compared to an earlier study using the original protocol.


Subject(s)
Blastocyst/physiology , Cryopreservation/veterinary , Embryo Transfer/veterinary , Litter Size , Swine , Animals , Cryopreservation/methods , Embryo Culture Techniques/veterinary , Female , Hot Temperature , Pregnancy , Superovulation
7.
Theriogenology ; 61(7-8): 1533-43, 2004 May.
Article in English | MEDLINE | ID: mdl-15036983

ABSTRACT

The objective was to determine farrowing rates and litter sizes that could be achieved in a typical farm-to-farm porcine embryo transfer program using vitrified blastocysts that were zona pellucida intact when cryopreserved. The embryos were transferred surgically on-farm into recipient sows that were managed throughout gestation and farrowing under the same conditions as other sows in the herd. Twenty recipient sows (mean parity 2.1) received a total of 568 embryos; seven received 203 embryos derived from donor sows, five received 139 embryos from gilts and eight received a mixture of 161 embryos from sows and 65 from gilts. Sixteen sows (80%) were confirmed pregnant at approximately 35 days gestation, 15 farrowed at full term (farrowing rate 75%). One sow died during gestation (with a total of 18 fetuses in utero). A total of 123 piglets were born (mean, 8.2), of which 115 were born alive (mean, 7.7). Of the 568 embryos transferred to all 20 sows, 21.6% resulted in piglets born and 29.0% survived to produce piglets in sows that farrowed. There were no significant differences in embryo survival among sow, gilt or mixed sow and gilt embryos. The ratio of males to females was 71/52 and the mean birth weight was 1.6 kg (range 0.6-2.6 kg). In conclusion, vitrified zona pellucida intact embryos can be used to transfer genetic material from farm-to-farm with acceptable reproductive performance.


Subject(s)
Cryopreservation/veterinary , Embryo Transfer/veterinary , Litter Size , Swine/physiology , Animals , Birth Weight , Blastocyst/physiology , Female , Male , Parity , Pregnancy , Sex Ratio , Tissue Donors , Tissue and Organ Harvesting/veterinary
9.
Arch Psychiatr Nurs ; 15(5): 214-22, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11584350

ABSTRACT

A true experimental, posttest only, control group design was used to pilot test the effectiveness of a telephone nursing intervention in increasing community survival, and decreasing the number and length of rehospitalizations for persons with schizophrenia. The vulnerability model was used as a framework for the study. The intervention was hypothesized to function as a moderating factor to reduce the effects of stress on vulnerable persons with schizophrenia. Experimental subjects received telephone nursing intervention weekly for 3 months; control subjects received informational calls at weeks 6 and 12. Readmission rates were 13% (n = 2) for experimental subjects and 23% (n = 5) for controls. Compared with controls, experimental subjects experienced a 4% increase in community survival and a 27% reduction in length of stay if readmission occurred. These preliminary data suggest that telephone intervention can increase community survival in persons with schizophrenia. Future studies should focus on increasing sample size and refining the intervention.


Subject(s)
Adaptation, Psychological , Aftercare/organization & administration , Counseling/organization & administration , Psychiatric Nursing/organization & administration , Schizophrenia/nursing , Schizophrenic Psychology , Social Support , Stress, Psychological/nursing , Stress, Psychological/prevention & control , Telephone , Adolescent , Adult , Aged , Female , Humans , Length of Stay/statistics & numerical data , Male , Middle Aged , Nursing Evaluation Research , Patient Education as Topic/organization & administration , Patient Readmission/statistics & numerical data , Pilot Projects , Program Evaluation , Schizophrenia/complications , Stress, Psychological/etiology , Stress, Psychological/psychology , Time Factors
10.
J Am Coll Health ; 49(6): 299-306, 2001 May.
Article in English | MEDLINE | ID: mdl-11413947

ABSTRACT

The authors tested the long-term effectiveness of a cognitive-behavioral group intervention in reducing depressive symptoms, decreasing negative thinking, and enhancing self-esteem in 92 college women aged 18 to 24 years who ere at risk for clinical depression. The women were randomly assigned to either an experimental or a no-treatment control group. The experimental group participated in a 6-week cognitive-behavioral intervention that targeted identification and reduction of negative thinking, using such techniques as thought stopping and affirmations. Data on depressive symptoms, self-esteem, and negative thinking were collected before the intervention and at intervals of 1, 6, and 18 months postintervention. The women in the intervention group experienced a greater decrease in depressive symptoms and negative thinking and a greater increase in self-esteem than those in the control group. The beneficial effects continued over an 18-month follow-up period. These findings support the importance of thought stopping and affirmations as prevention interventions with at-risk college women.


Subject(s)
Cognitive Behavioral Therapy , Depression/psychology , Students/psychology , Adolescent , Adult , Analysis of Variance , Chi-Square Distribution , Depression/epidemiology , Female , Follow-Up Studies , Humans , Kentucky/epidemiology , Prevalence , Self Concept , Time Factors
11.
Public Health Rep ; 115(4): 370-7, 2000.
Article in English | MEDLINE | ID: mdl-11059432

ABSTRACT

The authors describe the development and evaluation of a continuing education program in biostatistics and epidemiology. Short courses were presented to public health and mental health professionals using teaching strategies that included lecture, discussion, practice-oriented examples, and interactive problem-solving. A total of 1723 health professionals attended one or more of the 120 courses presented from 1992 to 1996 in seven US states. Most course participants were female: the highest education level for 40% was a bachelor's degree, while 42% had advanced degrees. Approximately 66% of participants signed up for continuing education credits. The program represents a successful partnership between an academic institution and health agencies in a seven-state region.


Subject(s)
Biometry , Education, Continuing , Epidemiology/education , Program Development , Public Health/education , Adult , Aged , Female , Humans , Male , Middle Aged , Program Evaluation , United States
12.
Nurs Res ; 49(4): 201-7, 2000.
Article in English | MEDLINE | ID: mdl-10929691

ABSTRACT

BACKGROUND: One of every three women between 18 and 24 years of age may be significantly depressed. Younger women have shown increasing rates of unipolar depression since the 1950s, and the average age of onset continues to decline. OBJECTIVES: To examine the prevalence and correlates of high depressive symptoms in single college women 18 to 24 years of age. Negative thinking was posited to mediate the relationship between self-esteem and depressive symptoms. METHODS: A sample of 246 women was recruited from a university student body. Each woman completed a survey that included the Center for Epidemiologic Studies-Depression Scale, the Beck Depression Inventory, the Rosenberg Self-esteem Scale, the Crandell Cognitions Inventory, and the Automatic Thoughts Questionnaire. RESULTS: Of the women, 35% had high depressive symptoms. Negative thinking mediated the relationship between self-esteem and depressive symptoms. However, self-esteem also showed a weak direct effect on depressive symptoms. CONCLUSION: The findings suggest that negative thinking may play an important role in the development of depressive symptoms in college women.


Subject(s)
Depression/epidemiology , Psychological Tests , Self Concept , Students/psychology , Adult , Depression/diagnosis , Female , Humans , Kentucky/epidemiology , Logistic Models , Negativism , Prevalence , Universities
13.
J Nurs Scholarsh ; 32(2): 145-51, 2000.
Article in English | MEDLINE | ID: mdl-10887713

ABSTRACT

PURPOSE: Although cognitive-behavioral interventions have been successful in treating depression, no studies were found that focused solely on reducing negative thinking via group intervention as a means of preventing depression in at-risk groups. The purpose of this randomized controlled trial was to test the effectiveness of a cognitive-behavioral group intervention in reducing depressive symptoms, decreasing negative thinking, and enhancing self-esteem in young women at risk for depression. DESIGN: A randomized controlled trial with 92 college women ages 18 to 24 who were at risk for depression was conducted. METHOD: Participants were randomly assigned to either the control or experimental group. The experimental group participated in a 6-week cognitive-behavioral group intervention. Data on self-esteem, depressive symptoms, and negative thinking were collected via self-report questionnaires from control and experimental groups at baseline, 1 month after the intervention, and at 6-month follow-up. Data were analyzed using mixed-model methodology and the Cochran-Mantel-Haenszel chi-square test. FINDINGS: Compared to those in the control group, women who received the intervention had a greater decrease in depressive symptoms and negative thinking and a greater increase in self-esteem, and these beneficial effects were maintained over 6-months. CONCLUSIONS: The findings document the effectiveness of this cognitive-behavioral group intervention and indicate empirical support for the beneficial effects of reducing negative thinking by the use of affirmations and thought-stopping techniques on women's mental health.


Subject(s)
Cognitive Behavioral Therapy/methods , Depression/therapy , Psychotherapy, Group/methods , Thinking , Adolescent , Adult , Analysis of Variance , Female , Humans , Self Concept
14.
J Reprod Med ; 45(6): 469-75, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10900580

ABSTRACT

OBJECTIVE: To compare the rates of and indications for labor induction between a university hospital and two community hospitals and to examine the risk of cesarean delivery among labor induction cases. STUDY DESIGN: Labor induction cases over a six-month period were included (N = 536). Medical records were reviewed by a trained abstractor using a standardized form to determine maternal characteristics, reason for induction and perinatal outcomes. RESULTS: Rates of labor induction were significantly different between the three hospitals: university, 18.2%; community hospital A, 21.4%; community hospital B, 33.7% (P < .001). At the university hospital, 95% of labor inductions were medically indicated using American College of Obstetricians and Gynecologists (ACOG) criteria. Forty-four percent of labor inductions at community hospital A and 57% at community hospital B were for elective reasons. Cesarean rates among induction cases were highest at the university hospital (19%) as compared to community hospital A (15%) and community hospital B (11%), although the difference was not statistically significant. Parity, race and cervical status, but not elective induction, were significantly associated with cesarean delivery. CONCLUSION: Labor induction was more frequent in community hospitals but more likely to meet ACOG-approved indications at the university hospital. The more-frequent inductions at the community hospitals did not result in higher cesarean rates.


Subject(s)
Cesarean Section/statistics & numerical data , Hospitals, Community/statistics & numerical data , Hospitals, University/statistics & numerical data , Labor, Induced/statistics & numerical data , Adult , Female , Humans , Medical Records , Oklahoma/epidemiology , Pregnancy , Retrospective Studies
16.
Paediatr Perinat Epidemiol ; 14(2): 172-8, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10791662

ABSTRACT

The interobserver reliability of histopathological features in the placenta was examined. Two pathologists independently reviewed slides from 250 placentas. The pathologists were given a morphological description of the placenta, but were blinded to clinical status, gestational age and original diagnoses. A protocol for diagnosis and grading of features was first developed and pilot-tested. Definitions and criteria were refined and elaborated. A range of features was examined including inflammatory lesions, features indicative of reduced uterine blood flow and other miscellaneous histopathological changes. Weighted kappa coefficients were calculated. The effect of multiple features on reliability was examined by stratifying on the presence of a second feature and calculating stratum-specific kappa coefficients. Results indicated good to excellent agreement for diagnoses of chorioamnionitis, cord vasculitis, funisitis and villitis (kappa(w) range 0.70-0.83). Agreement between observers was more variable for the diagnosis of reduced uterine blood flow states. Excellent agreement was observed for the diagnosis of meconium staining of the placenta (kappaw = 0.79). In general, lower levels of agreement were observed for features in the presence of a second feature. Reproducible measures are a prerequisite to using placental histopathology for diagnostic and prognostic information. This study demonstrated reliable placental diagnoses can be achieved through a standardised protocol.


Subject(s)
Placenta Diseases/diagnosis , Placenta Diseases/pathology , Placenta/pathology , Clinical Protocols , Female , Humans , Observer Variation , Peer Review, Health Care , Placenta/blood supply , Placenta Diseases/classification , Placenta Diseases/physiopathology , Pregnancy , Reproducibility of Results
17.
Biochem Pharmacol ; 52(10): 1507-13, 1996 Nov 22.
Article in English | MEDLINE | ID: mdl-8937464

ABSTRACT

Suicide inhibitors of cytochrome P450 families are excellent tools to predict which isoforms mediate the metabolism/activation of a variety of chemical agents. We compared the inhibitory effects of several arylalkynes on mouse cytochromes P450 with published data for the rat model. The inhibition of P4502b specific dealkylation of benzyloxyresorufin by 2-ethynylnaphthalene (2-EN), 5-phenyl-1-pentyne (PPY), 4-phenyl-1-butyne (PBY), and 9-ethynylphenanthrene (9-EPh) was measured in hepatic microsomes from male mice treated with 1,4-bis[2-(3,5-dichloropyridyloxy)]-benzene (TCPOBOP) to induce cytochrome P4502b. Pulmonary microsomes were prepared from untreated mice. 9-EPh, 2-EN, and PPY caused a time-, concentration-, and NADPH-dependent loss in P4502b activity in both tissues. PBY, however, demonstrated this type of inhibition only in liver microsomes. The IC50 was calculated for both liver and lung microsomes and compared with published Ki (concentration required for half-maximal inhibition) or KI (concentration required for half-maximal inactivation) values for the rat. PPY, PBY, and 9-EPh were equally effective inhibitors of mouse P4502b and rat P4502B1. 2-EN was a 5- to 10-fold less potent inhibitor of mouse P4502b, as compared with the rat, even though it was shown to bind to the active site of the mouse isoform as demonstrated by its metabolism to 2-naphthylacetic acid. These data suggest that the active site of the mouse P4502b enzyme is functionally similar to the rat P4502B isoform, with the exception of the disparity in its susceptibility to inactivation by 2-EN as measured by the Ki values.


Subject(s)
Alkynes/pharmacology , Aryl Hydrocarbon Hydroxylases , Cytochrome P-450 Enzyme Inhibitors , Enzyme Inhibitors/pharmacology , Steroid Hydroxylases , Animals , Cytochrome P-450 Enzyme System/metabolism , Cytochrome P450 Family 2 , In Vitro Techniques , Kinetics , Lung/enzymology , Male , Mice , Microsomes/enzymology , Microsomes, Liver/enzymology , Naphthalenes/pharmacology , Oxazines/metabolism , Phenanthrenes/pharmacology , Rats
18.
Obstet Gynecol ; 87(5 Pt 1): 771-8, 1996 May.
Article in English | MEDLINE | ID: mdl-8677084

ABSTRACT

OBJECTIVE: To investigate the epidemiologic and pathogenetic significance of placental features and neonatal outcome in a high-risk population. METHODS: One pathologist examined 1252 placentas from clinically selected at-risk singleton pregnancies. Placental pathology features were analyzed relative to gestational age and status of the newborn, including fetal growth restriction (FGR), low 1-minute Apgar score, infection, liver disorder, anomalies, and death in the immediate postnatal period. RESULTS: The most frequent placental pathologic features were ischemic change, meconium staining, and chorioamnionitis. Only 8% of placentas were considered normal. The number of features per placenta increased with gestational age. Among preterm infants, chorioamnionitis occurred most frequently with low 1-minute Apgar score (40%), clinically apparent infection (43%), liver disorder (43%), and anomalies (42%), compared with healthy newborns (15%). Chorioamnionitis at term was most frequent among infants with low 1-minute Apgar score (26%), infection (30%), and liver disorder (23%), compared with healthy newborns (16%). Meconium and ischemic changes were most frequent in placentas from healthy newborns, compared with affected newborns, regardless of gestational age. Multivariable analyses revealed an independent association between chorioamnionitis and low 1-minute Apgar score (P < .05), and both chorioamnionitis and villitis were associated with newborn infection (P < .05). CONCLUSION: The frequency of many major pathologic placental features, especially ischemic changes and meconium, in the absence of immediately detectable abnormality is relatively high. Thus, continued follow-up is needed to determine their long-term clinical significance. In addition, associations of ischemic changes and infarction with FGR in term infants suggest that need for comprehensive investigations of the effects of histopathologically apparent low placental blood flow.


Subject(s)
Placenta Diseases/epidemiology , Placenta/pathology , Pregnancy Outcome/epidemiology , Pregnancy, High-Risk , Apgar Score , Chorioamnionitis/epidemiology , Chorioamnionitis/pathology , Female , Gestational Age , Humans , Infant, Newborn , Infant, Newborn, Diseases/epidemiology , Infant, Premature, Diseases/epidemiology , Logistic Models , Multivariate Analysis , Placenta Diseases/pathology , Pregnancy
19.
J Toxicol Environ Health ; 47(4): 379-94, 1996 Mar.
Article in English | MEDLINE | ID: mdl-8600290

ABSTRACT

Induction of CYP1A1 is one of the best characterized responses to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). EROD activity has been used as an enzymatic marker for CYP1A1 following TCDD treatment. Enzymatic markers for the induction of CYP1A2 by TCDD are not as well characterized. The present study examines the relationship between CYP1A1 and CYP1A2 protein and the corresponding enzymatic markers. Induction of hepatic ethoxyresorufin O-deethylase (EROD) activity and methoxyresorufin O-demethylase (MEROD) and acetanilide 4-hydroxylase (ACOH) activity (both markers for CYP1A2) were analyzed in 8-wk-old male and female Fischer 344 rats treated orally with either 0, 0.1, 0.3, 1.0, or 3.0 micrograms TCDD/kg. There were no sex differences in basal EROD or ACOH activity. MEROD activity was significantly greater in control males than in control females. Significant induction of EROD activity in females occurred at slightly lower doses of TCDD compared to males (0.1 vs. 0.3 micrograms/kg, respectively); however, a greater absolute and a larger fold induction of EROD activity was seen in males compared to females at all doses tested except 0.1 micrograms/kg. EROD activity did not attain a maximum in either sex. Similarly, MEROD activity was induced at lower doses of TCDD in females than in males (0.1 vs. 0.3 micrograms/kg, respectively). MEROD activity was maximally induced at 0.3 micrograms/kg in males. In females, MEROD did not attain maximum induction at the doses tested. ACOH activity was induced at doses as low as 0.3 micrograms/kg in both sexes, and the dose-dependent increases in activity were equivalent in males and females. Both ACOH and MEROD activity correlated well with CYP1A2 levels as determined by Western blot analysis, although there was a greater fold induction of protein than either MEROD or ACOH. Although MEROD and ACOH are both markers for the same response, MEROD activity may be a more useful marker because it is the quicker and more sensitive of the two assays.


Subject(s)
Aryl Hydrocarbon Hydroxylases/biosynthesis , Cytochrome P-450 Enzyme System/biosynthesis , Oxidoreductases/biosynthesis , Polychlorinated Dibenzodioxins/toxicity , Animals , Blotting, Western , Cytochrome P-450 CYP1A1 , Cytochrome P-450 CYP1A2 , Dose-Response Relationship, Drug , Enzyme Induction , Female , Liver/enzymology , Male , Polychlorinated Dibenzodioxins/metabolism , Rats , Rats, Inbred F344
20.
Cancer Res ; 55(21): 4875-80, 1995 Nov 01.
Article in English | MEDLINE | ID: mdl-7585523

ABSTRACT

To investigate the hypothesis that tumor promotion by chlorinated aromatic hydrocarbons involves Ah receptor occupation and subsequent induction of cytochromes P-450 1a-1, effects of Aroclor 1254 or 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) were examined in N-nitrosodiethylamine-initiated mice with different Ah receptor phenotype. Levels of cytochromes P-450 1a and 2b were measured by enzyme assay and Western immunoblots. Males of the C57BL/6, DBA/2, or (C57BL/6 x DBA/2)F1 (hereafter referred to as "B6D2F1") strain were initiated with a single i.p. dose of N-nitrosodiethylamine (90 mg/kg body weight), followed by either multiple doses of TCDD (0.05 micrograms/kg) weekly or Aroclor 1254 chronically in the diet (100 ppm) for 20 weeks, and then no treatment for 24 weeks. Lung tumor incidence or multiplicity was not altered by either of the promoters. Liver tumor incidence was similar among the three strains after N-nitrosodiethylamine alone (14, 21, and 21%, respectively). In DBA/2 mice, TCDD neither induced Cyp 1a nor promoted liver tumors. Aroclor caused an 8-fold induction of hepatic Cyp 2b, which was its maximum at the 12-week time point but did not promote tumors. Inductions of hepatic Cyp 1a by TCDD and 1a and 2b by Aroclor were similar in C57BL/6 and B6D2F1 mice, but tumor promotion responses were quite different. Dietary Aroclor significantly promoted liver tumors in C57BL/6 mice (59 versus 14%) but not in B6D2F1 mice (24 versus 21%). Repeated TCDD promoted only in B6D2F1 mice (52 versus 21%) and not in C57BL/6 mice (19 versus 14%). Thus, whereas these data confirm that a functional Ah receptor is required for liver tumor promotion, the degree of activation as measured by induction of Cyp 1a is not directly related to the degree of tumor-promoting capability. Other genetic factors must play a role in mediating the final tumor outcome.


Subject(s)
Aroclors/toxicity , Carcinogens/toxicity , Diethylnitrosamine/toxicity , Liver Neoplasms, Experimental/chemically induced , Polychlorinated Dibenzodioxins/toxicity , Animals , Blotting, Western , Cytochrome P-450 CYP1A1 , Cytochrome P-450 Enzyme System/biosynthesis , Cytochrome P-450 Enzyme System/metabolism , Enzyme Induction , Liver Neoplasms, Experimental/enzymology , Liver Neoplasms, Experimental/pathology , Lung Neoplasms/chemically induced , Lung Neoplasms/enzymology , Male , Mice , Mice, Inbred Strains , Oxidoreductases/biosynthesis , Oxidoreductases/metabolism , Receptors, Aryl Hydrocarbon/physiology
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